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VIEWS: 62 PAGES: 8

									Monash
Review
What'sNew In EducatIOn,Research
and Community Service                                  Or Pe ter Temple -Sm ith (centr e) and mlc ro- .
                                                       su rgeon Mr Graeme Southwic k (rig h t) att emp t to
                                                                              t
                                                       co rrec t male toterttt tv by mic ro-surgery . The

2-81                                                   tech nique enable s the m to by-pass a blockage
                                                       in the epid idymis by joining the vas de fere ns
                                                       (diagram rig ht) directly to th e minute ep idi dym is
                                                       duct . The at tending nurse is Sis ter Ronnie Ho b­
lSSN 0159-950                                          day.
                                                       Phot o: Terry Martin. Diagram : Mrs Sue Sim pson .
                                                                                                                                          ~""=:--- ~f~~5 ':; :I~nl ~~o
                                                                                                                                                        the epldldVMls




    New hope on male
                                                                                                     v• •
                                                                                                                  ce t e r e ns




    infertility
                                       vas defe rens store sperm prior to ejaculation .
                                                       Dur ing their passage dow n the epididymis
                                                       the sperm undergo a maturation process.
      MONASH rellearchers are developing               becoming active and fert ile.
  mlcro-surglcel and diagnostic techniques                 Dr Peter Temple-Smith. of the Monash                 down the epididymis and his sperm were ac­
  wh ich could lead to Improved treatment of           anatomy department. and micro-su rgeon. Mr               t ively motile and appear structuralty mature.
  llome typell of Infertility In men.                  Gra8me Southwick, using rabbits , have                    Because of the low level of the jo in there is a
      It is estimated that one in 10 couples have      developed a micro -surg ical technique Which             good chance that the sperm will be fertile .
  an infertili ty problem . In about 40 per cent of    enables them to by-pass the blockage in the                  The continued post -operative absence of
  cases the infert ility is due to the ma le. One      epididym is by joining the vas deferens direct ­         sperm in the other men does not neceasarily
  man in 26 is infert ile, and, from research at       ly to the minute epididymis duct.                        mean that their operat ions were unsucces­
  Mona sh, it seems that one in 35 or 40 is ac­            Using single duct microsurgery they have             sful. Some past clin ical observations Indicate
  tually sterile.                                      achieved a 90 per cent success rate in                   that sperm may not appear in the ejaculete
      The Monash research, wh ich Is being done        rabbits. All 90 per cent had healthy young.              unt il 12- 1B month s afte r the anastomosis
  in conjunction w ith the Infertility Clinic at           In conjunction w ith Professor David de              has been made, especially if the vas has bean
  Prince Henry's Hospital, is concerned ma inly        Kretser. they are now beginn ing to use th is            joi ned to the head of the epididymis.
  w ith a type of male infertility in wh ich sperm     techn ique in men who have an obstruction                    The Mo nash team hope that the ir research
  are produced in the testes , but are unab le to      with in the epididymis and are infertile.                using the rabbit w ill shed some light on this
  pass into the vas deferens, the sperm's exit             De Kretser says the by-pass operation,               aspect of the operetion.
  route , beceuse of a blockage In the                 called an anastomosis, has been done before                  " Obviously, if t he join la made at higher
  epididym is.                                         as a normal surgica l procedu re, but with a             levels, the prognosis is not as good, " de
      The epididym is lies behind t he testes and      success rate of less than five per cent.                 Kretser says, " since sperm need to pass
  consists of a coiled system of 10- 15 t iny              Results were poor, he says. because the              down the tract to mature and it Is more
  ducts wh ich lead to 8 single convoluted duct        vas deferens was joined to the whole                     difficult to join tha vas deferens to the smaller
  wh ich, in turn , leads into the vas deferens.       epididym is, not J t to a single duct.
                                                                          UB                                    diameter ducts. "
     The epididym is and the first portion of the          Southwick and Temple-Smith 's micro­                     The diagnostic method whi ch enables the
                                                       surg ical techn ique has now been teated at              Monash team to ident ify patients unsuitable
                                                       The Avenue Hospi tal on about one dozen                  for the obstru ct ion-reversal operat ion arose
    M'ONASH REVl'EW'is produced four times             men from the Infertility Clinic at Prince                from the discovery that some men have nor­
    yearly by the Information Offrca, Monash           Henry's Hosp ital.                                       mal sperm counts but their sperm are "quite
    University. Wellington Road. Clayton, vsc­             So far only one of t hese men has produ ced          inact ive" . The same men suffer from a
    toria. 3 16 8 . Inquiries should be addressed to
    the Editor. c/o the Information Office.            a heaIthy sperm count after the operat ion. In           respiratory disease called bronch iectasis .
                                                       t his case the loin was made about half way
                          01
              Regisle red 1 pos llng as
              a pcnoorcat. Cateqory B                                                                                                         Co ntinu ed overlea f

MONASH REVIEW                                                                                                                                                      JUNE
Picasso
goes
public
    MONASH art historian Memory Hol ­
loway has been commissioned by the
National Gallery of Victoria to produce a
book on Its small but fine collection of
Picasso etchings. which are rarely seen by
the public.
    The book, which is expected to be
publ ished later th is year , w ill bring the 22
etchings and other engravings together for
permanent display .
    The prints, stored in the Prints and
Drawings Room at the National Gallery , can                                                                     Monash art hist orian Memory Holloway (ce ntre)
                                                                                                                conduct s a tutorial on Picas so at th e National
only be shown occasionally because of the ir                                                                    Galle ry. She has be en com missione d by the
frag ility. They are very sensit ive to light and        re-valuation of Picasso , who is regardad by           Gallery to produc e a book on its tin e but rarely
                                                         m any art ists and art histo rians as the art ist of   se en Pica sso etc hin g s. Some of the etchin gs
could be ser iously damaged if put o n                                                                          are pictured abo ve.
permanent display.                                       the century because of his innovation, artistic                                    Phot o: Ric k Crompton.
    Holloway says the book wi ll enab le many            techn ique and infl uence on modern art.
peop le, who might not otherwise have the                    This renewed interest in Picasso reached
opportunity , to enjoy the etch ings , wh ich            it s peak in 1979 with a huge exhibition in
represent the finest Picasso collect ion in              Paris of the art ist's works, donated by his
                                                         fam ily to the Frenc h nat ion in lieu of death           Holl ow ay saw both exh ibit ions . The suc ­
Australia. The only other major Picasso
                                                         duties.                                                cess of the exhibit ions and the renewed
wo rks in Austra lian galleries are a painting in
                                                             SUbsequen tly the works were sent to New           interest in Picasso wh ich they generated,
 the Queensland National Gallery and a
                                                         York for a large Picasso retrospective before          gave her the idea of producing a permanent
recent ly acqu ired paint ing in the NSW gal ­
                                                         being returned for perm anent hous ing in a            record , in book form , of the V ictor ian
 lery.
                                                         Paris museum.                                          colle ct ion .
    Publication of the book is part of a general
                                                                                                                   The earliest etching in the National Gallery
                                                                                                                of Victoria's Picasso collect io n is dated 1904.
                                                                                                                The last one was done in 1973.

Malei n f ertiiit Y                                     Conti nued from Page 1                                     The 1904 etching, called " The Frugal
                                                                                                                Meal", depicts a poverty-stricken man and
                                                                                                                woman sitting in a cafe.
                                                                                                                   Holloway says the etch ing was done
   " If you examine the teils of the sperm of            team plans to examine cil ia from the nasal            Picasso dur ing his Blue Period, when , dogg e"
these men end the cilia from their resp iratory          epithelium of the patient to see If It is abnor­       by poverty and failure, he began to paint in
surfaces under the microscope, you w ill find            mal.                                                   melancholic, predominantly blue tones.
the same abnormality:' de Kretser says.                      " If the nasal cilia lack dyne in arms, " de          The subject matter of the 1904 etching
   "A sperm tail has nine doublet tubules                Kretser says, " cilia in the epididymis w ill          underl ines Picasso 's compassion for society's
which run the ent ire length of the tall ." he           probably lack them also and w ilt be unable to         outcasts, a concern wh ich was to appea r
says. "I n cross -sect ion , they look like the d ial    propel the sperm down the tube .                       time and again in his art .
of a telephone.                                              "ln that case, there is no point in                   Ten of the Nat ional Gallery's etc hings, she
   " In normal sperm there are tiny arms,                attempting to reverse the obstruction. The             says, are from t he famous Vollard Sui te, a
called dyne in arms , which extend from each             sperm would remain im mot ile even if the              collection of 100 engravings and etch ings
of these m icro -tubule pairs . W ithout these           obstruction were reversed. "                           w hich Picasso did over a 1O-year per iod fro m
arms the sperm cannot become motile.                         As well as cond uct ing further research on        1937 for publ isher and art dea ler Ambroise
   " These arms are missing from the sperm               human subjects, the Monash team Is                     Volla rd.
of men In whom the sperm are inactive. They              continuing its research on rabb its because of            " The etch ings were executed in exchange
are missing also from the respiratory ci lia ,           the ir fecundity and the sim ilar ity of the ir        for some paintings that Picasso wanted: ' she
which also serve a locomotive function ,                 reproductive systems to humans.                        says.
sweep ing mucus and debr is out of the                       In these exper iments, the vas deferens will          " They are very evocative and sensual
resp iratory passages."                                  be jo ined et various locations in the body and        pieces. done with utter ease. I th ink th is is
   Some men who have an obstruction in the               head of the animal's epididymis in an attempt          largely related to the fact thet by th is time
epididymis also suffe r from bronchiectasis.             to perfect the techn ique and to determine the         Picasso had left his ballerina w ife Olga , who
   The Monash team is working on the                     distance down the tube that the sperm has to           wa s socially very ambitious, and had met a
hypothesis that In these cases the                       travel to become mature. Present indications           woman called Marte-Therese Walter.
obstruction Is a "plug" of sperm which is                are that it is not very far.                              " He seems to have been very happy with
unable to move because the cilia that nor ­                  The research is being funded by the                Marie-Therese. It was a very relaxed and
mally propel it down the epididym is leck                National Health and Medical Research Coun­             peaceful time for Picasso . His happiness ap-
dynein arms and are therefore immotite.                  cil. Monash University and the World Health
    Before carrying out further operations, the          Organ isation.                                                                      Contin ued on Page 3
MONASH REVIEW                                                                     2                                                                          JUNE
In vitro
team
freezes
embryos
     MONASH researchers at the Queen
Victoria Medical Centre are developing
techniques for the freezing and
preservation of human embryos,
     The work, which has been approved by the
hospital 's ethics committee, is aimed at
improving the success rate in the Monash-led
in vitro fert ilisation program .                                                                          .:..:tE~lIIl1t ;~ . . . . - -,

     The Mona sh team , led by Professor Carl                         The wo rld 's first in vi tro twins. A m anda (le ft) an d Step hen Mays.

                                                                                               Photo: Chr is Barham. Copyright: Daily Mail, London. ANG Ltd.

Wood, has already announ ced the birth of
the world's first in vitro twins, Amanda and        bleeding . Uterine bleeding occurs in about 15       and then plunged into liqu id nitrogen. Its
     sphen Mays, who were born at the Queen        per cent of patients, he says, and is not             temperature then is minus 196 degrees C. At
  icto ria Medical Centre early this month .       pecul iar to mothers undergoing the In vitro          that temperature all metabolic processes
Stephen underwent surgery for a heart
                                                   procedure . It is " feirly common" in normal          stop and the embryo can be kept frozen In­
defect. Six babies have now been born in the
program as a result of fertilisation of the        pregnancy.                                            defin itely . as far as is known .
moth er's egg outside the womb. and a birth            The embryo will not implant in the womb              " The only thing we 've been concerned
is expected. on average, each month until the      if there is bleeding. he says. So embryo              about is the effect of background radiation
end of the year.                                   transfer has to be delayed to a suitable cycle .      which might damage the cells ," Trounson
     The work on embryo freezing is being              The alternative to freezing the embryo for        says. " But research by Dr David Whit·
done by Dr Alan Trounson, a lecturer in the        later transfer is to collect another egg by           tlngham on mouse embryos suggests that
Monash department of obstetrics and                 laparoscopv . which would mean an extra              this is no problem. "
gynaecology, and Mrs Linda Mohr. a                 operation for the mother. with no guarantee              To thaw the embryo, the procedure is
research assistant.              .                 that conditions would be right the next time.         reversed.
     With the consent of the parents, they have        Another situation in which problems can              Trounson says a number of normal,
successfully frozen a dozen embryos , all of       arise is when the mother becomes ill.                 healthy progeny have been born to mice and
which appeared to be normal on thawing.                Another factor which complicates the              cattle , as a result of implantation of frozen
Two of the embryos were transferred back           problem is the use of the ertificial hormones.        embryos. But, in cows. the embryos do not
into the mother's womb, but no pregnan cy          clomiphene and human chorionic                        seem to be viable unless they are frozen at
resulted .                                         gonadotrophin (HCGJ to induce ovulation. A            the blestocyst stage. By then the growing
     Trounson says the freezing techn iques are    side effect is that invariably two or more eggs       embryo is a bell of 120-150 cells
being developed to give the team "a little         are produced .                                        surround ing a central fluid-filled cavity.
more elasticity in its work on In vitro fer­           Tha fact that there are two or more ripe             If a healthy human embryo could be
tilisation " .                                     eggs increases the chances of growing an              grown in a nutritive madium to that stage,
     A number of situations can arise in which      ambryo . but it also creates an ethical              then frozen, and later transferred back to the
    "5 desirable to delay transfer of the embryo    problem . What do you do with the excess             womb. there would be no problem in
     ck into the mother's womb until the next       embryos? If the embryos are not transferred          achieving pregnancies from frozen embryos,
cycle, he says.                                    beck into the womb or used for further                Trounson says.
     One situation is where there is uterine       research, they have to be discarded .                    But viable human blastocysts cannot yet
                                                       " A fter lengthy discussions, " Trounson          be grown outside the womb, he says. The

Picasso                                            says, " t he hospital's research and ethics
                                                   committee recommended that. provided
                                                   parents give their informed consent, normal
                                                                                                         embryo has to be transferred at the eight-cell
                                                                                                         stage, or, at the earliest. the four-cell stage.
                                                                                                         The human embryos et the Queen Victoria
Co nnn ued Ir o m Pag e 2
                                                   excess embryos should be preserved by                 Medical Centre are being frozen at the four
pears to be reflected in his work in this period   freezing for possible re-implentation in the          and eight-cell stage.
which was prolific and very creative. "            future rather than being discarded .                     " W e believe that humen embryos will
    Holloway says there are also several               The technique which Trounson is using to          prove easy to freeze." Trounson says. " They
lithog raphs and a very fine drawing in the        preserve ambryos at the Queen Victoria                look as though they survive well. In terms of
Victorian collection. The drawing belongs to       Medical Centre is one wh ich he and Or                damage, our frozen human embryos look
Picasso's Cubist period , when he and the          Willadsen Steen developed et Cambridge                more like mouse embryos than cow embryos .
French painter Georges Braque attempted to         University in 1976 while conducting research             " The problem is we haven't done enough
look at an object from many different angles       on the freezing of cattle embryos.                    yet to work out the optimum method of
and build up a 3-dimensional image in paint            The embryo is first "passaged" through            freezing. and we will have to transfer at least
by reducing forms to simple planes, using a        three or four solutions containing. in                15 healthy thawed-out embryos to the womb
very small color range - virtually black and       increasing concentration. a chemical called a         before we can expect a pregnancy .
wh ite.                                            cryo -protectant. This chemical. either                  "After all, we used more than 300
    Some of Picasso's work is difficult to         glycerol or dimethy sulphox ide, enables the          embryos to get the procedure working for
understand, she says. But what he is often         embryo cells to survive freezing .                    cattle. and other researchers used thousands
trying to do is to dissect a figure into its           The solut ion containing the embryo is            of embryos to get it working for mice."
various parts and to present perception of en      cooled from room temperature to minus six                Trounson presented the results of his
object in its totelity - not only what we see      degrees C at which stage ice crystals start to        research to the recent 3rd World Congress on
at a particular moment. but also what we           form . It is then slowly cooled in a                  Human Reproduction In Berlin. Where he was
don't see but know is there .                      programmable freezer to minus 80 degrees C            one of three major lecturers.
MONASH REVIEW                                                             3                                                                           JUNE
Exploring

an ancient

way of life

    TWO boy scouts Investigating a cave at
Springfield Gorge. near LoncefleJd, last
year, discovered an old Aboriginal burial
site .
    Inside the cave was the dessicated body of
a young woman enclosed in a net bag.
Archaeologists believe the woman 's body
was placed in the cave about 300 years ago.
    Working in conjunction with the Vlctorlen
Archaeological Survey and the National
Museum . Monash botan ist Dr Beth Gott
has now identified the fibres used to make
and tie up the bag.                                                                                     Three hundred years ago the body ot an
    A painstaking examination of the largely                                                            aboriginal woman was pla ced in a bag in this
intect bag has shown that the flax used as a                                                            cave near t.en cettetd. Monash bot anist Beth
                                                                                                        Gott (le ft) has identified the fibres used to mak e
tie was made from a plant called DlaneUa                                                                and tie up the bag . The blue flax lily (Inset) was
revolute (the blue flax lily) . The main part of                                                        used 8S 8 tie .
the bag appears to have been made from the
inner bark of tha wattle.                                                                                   Gott says it began to disappear with the
    Gott works in the Monash botany                                                                      introduction of sheep and cattle which ate
department on a grant from the Australian                                                                not only the leaves of the plant but also its
Inst itute of Aboriginal Studies.                                                                        roots . which were very close to the surface .
     From the plant ramains at an                                                                           "Who can blame the Aborigines for raiding
 archaeological site in the Western District.                                                            farmers ' fields for potatoes?" she asks.
 she has also established that 19.000 years                                                                  By the time the first Europeans arrived the
ago - at the height of the glacial period in                                                            Aborigines had lived in the Western District
southern Austral ia when Australia was linked                                                           for 40,000 years at least and had achieved a
to Tasmania by a land bridge and the climate                                                             balance between population and resources .
generally was bitterly cold and dry - there                                                                 How did they manage this? It was not due
was a good fresh water stream in thet part of                                                            to starvation.
the Western District. at least.                                                                             Gott says some clues are emerging from
    The stream would have provided a good                                                                research in Africa , where it has been shown
food and water supply for the local                                                                     from analysis of blood samples that fre­
Aborigines.                                             There is a tendency also. she says. to think    quency of suckling appears to determine
     Gott infers the existence of the streem        that. because the Aborigines were a                 whether a woman conceives or not . W ith I
from deposits of seeds of the weter plant           stoneage people , and didn't engage in              almost continuous breastfeeding practised .. ,
 Mvrlophyllum as well as seeds of a species         farming. they had an inferior diet and              hunter gatherers. it seems, a hormone is
of Pimelee, Plmlllllll plIuclflorll. which she      lifestyle.                                          produced which, in effect, prevents ovulation,
 retrieved from the archaeological site.                She believes the use of fire and the                " Hunter gatherers suckle children
believed. on the basis of carbon dating. to be      gathering practices of the Aborig inal women        whenever the child requires it. not every four
 about 19.000 years old.                            were a type of farm ing , improving the growth      hours as European women do, but. perhaps .
    This particular Pimelea. which is               of food plants which they used.                     every 20 minutes:' Gatt says. " This elmost
 associated with mountain streams , is not              " The evidence from anthropological             continuous suckling produces a hormone
found today in the Western District . It is         studies shows that the hunter gatherers live        which basically prevents ovulation,
found only in mountain areas of eastern Vic­        very well :' she says. " The Aborig ines, before        " If the frequency of suckling is stretched
 toria ,                                            the Europeans came. had plenty of animal            to as much as four hours. the hormone Is ap­
    " It is remarkable that after being buried in   protein. as well as roots , seeds and fru it as a   parently not produced or is not produced
 the mud for 19 ,000 years the Pimelea seeds        food source.                                        regularly ."
 were quite recognisable: ' she says.                   " The Western District was full of swamps.          This frequency of suckling. Gott believes.
     It is only now , as evidence accumulates       which are ecologi cally very productive. There      could be one of the reasons for the
 from archaeological sites, Gott says. that we      were water birds . the eggs of water birds ,        Aborigines' success in balanc ing population
 are beginning to understand the complex            yabbles . eels, fish and fresh water mussels.       and resources.
 nature of the Abor igines' way of life.                " W e tend to forget how many swamp s               It could also hold the key to why the
     "We tend to think of them as being part of     there were in the Western Dist rict. So many        Aborigines did not engage in agriculture as
 the eco-system , but not affecting it very         have been c o m p l e t e l y drained for           we practise it .
 much : ' she says.                                 agriculture ,"                                          Go tt says there are a number of
     " This is a very wrong impression. The             One of the staple foods of the Aborigines       anthropologists who believe that a people
 Aborigines regularly used fire as a tool. They     at the time of the arrival of the first             only turn to agriculture when they are forced
 used controlled burning to bring up fresh          Europeans was murnong. a dandelion-like             to do so by population pressures.
 plants, open up the country, attract animals       plant with a yellow flower, whi ch, Gott says.          This was not necessary for the Aborigines
 to an area for hunting. or drive them to other     was then found allover the Western District.        who had managed to keep population and
 areas."                                            It has now almost disappeared.                      resources in balance .
MON A ~H   REVIEW                                                         4                                                                          JUNE
                                                                                                      Analysis of pollen samples taken by Dr A. Pete r
                                                                                                      Kershaw (tneet) from this crater lake on the
                                                                                                      Atherton Tableland shows a dramatic change in
                                                                                                      the Australian landscape over the past 120,000
                                                                                                      years . The predominance 01 eucalypts today
                                                                                                      may be due partly to the use of fire by the
                                                                                                      Aborigines.



                                                                                                          today in areas drier than those occupied by
                                                                                                          tropical rainforest. but Is only found in
                                                                                                          sma ll patches i n north -eastern
                                                                                                          Queensland .
                                                                                                      •	 From 38.000 to 10.000 years ago there
                                                                                                          was a dramatic change . Araucarla dry
                                                                                                          forest was replaced by Iclerophylt
                                                                                                          wood land. The emergence of the eucalypts
                                                                                                          as the dominant vegetation coinc ided with
                                                                                                          a decrease in rainfa ll and a sharp increase
                                                                                                          in charcoa l particles.
                                                                                                      •	 From 10.000 years ago almost to the
                                                                                                          present. much of tha Atherton Tableland
                                                                                                          was re-occupied by trop ical rainforest un­
                                                                                                          der increased rainfall levels.
                                                                                                           Recent changes In vegetation - caused
                                                                                                      by the activ ities of European settlement ­
                                                                                                      are indicated in the topmost sedlmant
                                                                                                      samples by the presence of pollen derived
                                                                                                      from introduced waed species. Thera Is also

Aborigines may have                                                                                   increased charcoal.
                                                                                                           The decline of Araucarla forest 38 .000
                                                                                                      yaars ago was associated with a decrease in

changed our landscape                                                                                 rainfall . but from evidence of sea-level
                                                                                                      changes. Kershaw says. it is likely that similar
                                                                                                      dry periods occurred prior to that.
                                                                                                           The question arises: Why did Araucarla
                                                                                                      forest. which must have covered extensive
     ABORIGINAL man may have been                   and a sim ilar increase in the charcoal curve.    areas between tropica l ra inforest and
responsible. at least In part. for the                  However. the pollen record et Lake            sclerophyll vegetation prior to 38 .000 years
proliferation of eucalypt forests which             George is not as deta iled as that of the         ago. manage to survive these earlier dry
dominate the Australian landscape today.            Atherton Tableland. wh ich. because of Its        periods and yet suffer so drast ically In the last
     Ana lysis of pollen samples from the           high t em perat ures and heavy rainfall .         one7
Atherton Tableland in nort h Queensland by          contains a rich variety of vegetation types            The answer. Kershaw believes. probably
Dr A . Peter Kershaw. of the Monash                 including rainfo rest comparable in diversity     lies in the int roducti on of the additional fac ­
geography department. shows a dramatic              with any to be found in the world's tropics.      tor. Abo riginal man. who is known to have
changa in the Australian lendscape over the             Kershaw obta inad cores of accumulated        been present in Austral ia for at least 36 .000
past 120.000 years.                                 organic mata rial from several locations in       years.
     Much of the change appears to be dua to        sediments that had accumu lated in volcan ic            He may. through his activ ities. have
variat ions in climate . but the dom inence of      crater lakes inland from Cairns.                   increased the level of burning to a point
    lerophyll vegetation. indicated by tha high         The cores were taken to a depth of 46         crit ical to the survival of this fire-sensitive
    lues of Cesuerlna and Eucalyptul pollen         metres . and have permitted pollen " map­         vegetation. already under stress from the
in the pollen record. begins about 38.000           ping" over a lengt hy period .                    decline in rainfall.
years ago. By then . it Is believed. the                " Pollen extracted from the cores was               Although the impact of the Aborigines on
Aborigines had arrived in Australia .               orig inally derived from plants surrounding the   the environment was significant. the max­
     The emergenca of the sclerophylls - par­       lake: ' Kershaw expla ins. " Therefore the         imum fir ing of forests does not appear to
ticularly the fira -tolerant Eucalyptus - as        pollen composition of each sample Is a             have occurred until the arrival of the
the dominant vegetation coincldas w ith a           raflection of the natu re of the vegetation        Europeans.
decrease in rainfall and a massive increase in      growing around the lake at the time of the              The Lake George research shows that
charcoal particles -        an indication of the    sample 's eccumu lation.                           charcoal revels after the arrival of the
increased prevalence of fire .                          " Variati ons in the pollen from sample to     Europeans initially reached more thsn 3~
     Kershaw believes that the "sharp Increase      sample record changes in the vegetation            times that of the highest level in the
 in the charcoal curve" . wh ich has been           from time to time ."                               Aboriginal period and more than 16 times
 mainta ined to the present day. Indicates that         Kershaw has Identi fi ed four dist inct        the peak levels of natura l fires In the earlier
 the increase in fires at th is time was due        periods from the pollen racord In this region      inter-glecials.
 largely to the activitias of man - the use of      over t he past 120.000 years:                           Ke rshaw 's work . wh ich has been
 fira by Abo rig ines for hunt ing and easier       •	 From 120.000 to 80.000 yeare ago.               cont inu ing for 10 years. Is partly aimed at
 trave l.                                              rainforest angiospe rms (flowering plants)      providing an hlatorlcel perspect ive for people
     Tha role of Abor iginal man in chang ing the      - sim ilar to those composing the comp lex      Invol ved In the management of forut
 landscape of Australia Is supported also by           trop ical rainforest existing over much of       resources.
 research at Lake Gaorge in NSW . wh ich               the Athe rton Tableland today -        were          "If you have an understanding of the
 pushes the pollen record back even further ­          dom inan t. At that time the cllmata was        natu re and clluses of vegetation changss
 to about 360.000 vears ego.                           probab ly very similar to that of today .       w ith in an area: ' he says. " It provides a
     The Lake George research. by Aus tralian       •	 From 80 ,000 to 38 .000 years ago.              realist ic basis for edoptlon of management
 Nat ional University pollen enalyst Dr G.             Araucarls forest con taining abundant            strateg ies wh ich w ill allow the survlval of
  Singh, shows a similar amergance of the              gymnosperms (conifers) covared much of          desired commun ities In the long term ."
  Eucalyptus as the dom inant vegeta tion in           the Tableland . This vegetat ion type occurs         The resaarch has been supoorted by
  ralat ivaly recant tlmee of the late Quaternary      extens ivelv in south-eastern Queensland         ARGC and Monesh Special Resesrch Funds.
MON ASH REVIEW                                                               5                                                                    JUNE
                                                                                                          chloramphenicol resistance is encoded on a

Antibiotic resistance                                                                                     plasmid. All the " Golden Staph " strains
                                                                                                          examined were resistant to methicillin. Some
                                                                                                           were resistant as well to either gentamicin or
                                                                                                           chloramphenicol. Others were resistant to

causes
                                                                                                   both of the antibiotics.
                                                                                                               Bacteria often cont ain several plasmids of
                                                                                                          varying size. The "Golden Staph " strains


concern
                                                                                                  isolated from the Royal Children's Hospital
                                                                                                          contained. in some cases, three plasmids ­
                                                                                                          one encoding resistance to chloram phenico l,
                                                                                                          one to gentamicin. and a th ird, whose
    THE emergence of bacterial strains                                                                     function has not been deciphered.
resistant to almost every usable antibiotic                                                                    " W e expect to find further examples of
is causing grave concern in many                                                                          plasm id-born antibiotic resistance in both S ,
Melbourne hospitals, according to Monash                                                                   Aureus and S. Epidermldis," 5kurray says.
microbiologist, Dr Ron Skurray.                                                                                An important part of the research is the
    He says strains of Staphylococcus                                                                     attempt to understand how antibioti c
Aureus. commonly known as " Go lden                                                                       resistant pla sm ids originated and how the
Staph", the most dangerous member of the                                                                  resistance is transferred to other strains.
staphylococcal group, are now resistant to                                                                     One possib ility is that antibiotic resistance
pen icillin, ampicillin, methicillin. cephalothin.                                                        may have been introduced into the plasmid
kanamycin , gentamicin. tobramycin , co­                                                                  on a transposon, a small piece of DNA which
trimoxazole. chloramphenicol. tetracycline                                                                has the ability to insert itself at specific points
and erythromycin.                                                                                         on a plasmid; Melbourne staphylococcal
   As well. several strains isolated from            ,        ~   lL· ~<.                                 strains are being examined for transpose
patients at Prince Henry's and St Vincent's          Ph ,D. student Bruce Lyon loads "Golden              by Skurray and May.
Hospitals have shown resistance to fus idic          Staph " plasmid DNA on to an agarose gel for              Skurray believes that in the case of
                                                     analy sis. Mon ash mIcro-b iologists Dr Ron Sk ur­
acid and rifampi cin , two of the th ree             ray and Or John May are attempllng to estab lish     staphylococci. resistance. once established in
remain ing antibi ot ics available for use.          the genetic basis for (he rapid emergence and        the plasmid, is transferred from one
                                                     spread of mull/pie antibiotic resistance, which Is
   " T h e only remaining antibiotic.                caus ing concern in Melbourne tiosottets.            bacter ium to another either by transduction
vancomycin. now forms the mainstay of                                          Phot o: Rick Cromp ton .   or transformation.
treatment in many hospital units and , while                                                                   In transduction. the bacterium is invaded
not yet reported, resistence to th is antibiotic     resistance is transferred among staphvlococ­         by a bacteriophage. a bacteria-attacking
may emerge," he says.                                cal stra ins.                                        virus , wh ich incorporates a small portion of
    Skurray and Dr John May, senior lec­                The research is being conducted in                the bacterial DNA within itself and escapes
                                                     coll aboration w ith Dr Tim Humphrey, of             with it when it causes the bacteria to burst
turers in the Monash mi crobiology depart­
ment. are attempting to establish the genetic        Prince Henry's Renal Unit and Dr John                open.
basis for this rapid emergence and spread of         Andrew, Director of Microbiology at St                    The bacterial DNA is introduced into other
multiple antibiotic -resistance as an aid to         Vincent's Hospital.                                  bacteria when the virus subsequently infects
more rational use of ant ibiotics.                      Skurray says ant ibiotic resistance can be        them. The introduced DNA may include the
    Recent studies at several Melbourne              encoded either on the main chromosome of             antibiotic resistance. The Monash team is
hospitals underline the gravity of the               the staphylococcus, or on a small , cir cular        screening "Golden Staph " stra ins for
situation. A study in the renal unit at Prince       piece of DNA (genetic material) called a             transdu cing-type bacteriophages.
Henry's Hosp ital has shown that approx­             plasmid. which can be obtained in the                     Transformation, the second method, is the
imately 250 days of hospitalisation from             laboratory separate from the chromosome.             uptake of " n aked" DNA by a bacterium.
peritonit is in ambulatory dialysis patients can        As well as contain ing genes for the ir own       When a bacterium dies it bursts open, spilling
be blamed on antibiot ic-resistant                   maintenance, plasm ids can carry genes for a         out its DNA. including the plasmid. which
staphylococci.                                       number of properties besides ant ibiotic             may be taken up by nearby bacteria.
   At St Vincent's Hospital 50 patients a day .      resistance . These in clude resistance to heavy
                                                                                                               Skurray says there is a third method .
on average . are either infected by multiple ­       metals. toxins, and, in some cases, genes
                                                                                                          transfer. a sexual -type of transfer called
resistant " Go lden Staph" or harbor it as car­      which enable the plasmid to be transferred to        conjugation, which occurs in Escherichia
riers. Furthermore, it is estimated that in ma­      other closely related bacteria.                      coli, a bacterium which inhab its the human
jor Melbourne hospitals approximetely 70                Recent studies by Skurray and May of              gut.
patients a day are unable to be discharged           " Golden Staph" isolated from the Royal                   It was thought that in thi s method. DNA
because they are " Go lden Staph" carriers ,         Children 's Hosp ital show that gentamicin and       was transferred through a tube -like stru cture
    " In addition to the difficulties associated                                                          called a pilus, on the su rface of " donor"
with the specialised nurs ing of these patients                                                           bacteria which attaches to the " female"
necessary to prevent cross-infection," Skur­                                                              during conjugation.
ray says. " the economic burden imposed by                                                                     It is now believed that the pilus is more
bed occupancy is estimated to be approx ­                                                                 like a grappling hook, Skurray says, It
imately $1 million per year in Melbourne."                                                                interacts with a receptor on the surface of the
    Skurray's and May's research is eimed at:                                                             recipient cell. then retracts, drawing the two
    • Identifying the way in which antibiotic                                                             bacteria into close contact. A bridge is
resistance is encoded in S. Aureus and also                                                               formed. and a single strand of plasmid DNA
in S. Epldermidls . The latter is a less                                                                  is transferred across.
dangerous relative of the "Golden Staph"                                                                       Conjugation is common in enteric
and is commonly found on the skin . S.                                                                    bacteria, Skurray says, but it has never been
Epidermldls has also shown a disturbing                                                                   observed in staphylococci.
tendency to develop multiple antibiotic                                                                       "U ndersta nding how antibiotic resistance
resistance and it may act as a gene pool to                                                               is spread and how resistance to different an­
spread resistance emong the more invasive                                                                 tibiotics is linked should help in establishing a
" Golden Staph" strains.                                                                                  more rational approach to the use of an­
    • Establishing patterns of linked                                                                     tib ion cs," he says.
resistance to several antibiotics, end                                                                        " It should also be possible to monitor the
    • Examin ing the way in which antibiotic                          Dr Ron Skurray                      emergence and spread of resistance to
MONASH REVIEW                                                               6                                                                         JUNE
Continued from Page 6

newly-developed antibiotics through our
studies ."
                                                    Enzyme 'marker' aids
    Parallel to the "Golden Staph" research,
Skurray is using recombinant DNA
technology (genetic engineering) to explore
                                                    lymphoma

the genetics of part of the "F factor", the
plasmid in E. Coli. which is responsible for
conjugation.
    " A considerable amount is known about
                                                    treatment

conjugation in E. Coli and the genes involved           MONASH researchers at the Alfred
are well characterised. However, the part we        Hospital have made an important advance
are examining is genetically uncharted," he         in the management of patients suHaring
says.                                               from tho blood disorder. non -Hodgkins
    H is group has cut the " F factor" region of
interest into small fragments using restriction
enzymes, chemicals which slice DNA at
                                                    lymphoma.
                                                        They have identified a biochemical
                                                    " marker" in the lymph glands and blood of                                 !
                                                                                                                             ./ II
                                                                                                                                   I'           if
specific sites .                                    these patients which enables them to predict       Clinical Associate Professor M. 8. Van der
                                                    the degree of "aggressiveness " of the             Weyden (right) and Dr T. E. Gan in the process of
    The fragments have been cloned on to a                                                             purifying the enzyme, foetaf thymidine k inase .
series of plasmid vectors and inserted into E.      disease and choose the most suitable               The enzyme serves as a "marker" which
Coli bacteria. Smaller pieces will be cloned        treatment.                                         enables them to predIct the degree of "ag­
                                                                                                       gressiveness " of the blood disorder, non­
on to other plasmid vectors, and the genetic            Non-Hodgkins Lymphoma is marked by             Hodgkins Lymphoma.
and biochemical properties of the "F factor"        proliferation of lymphocytes (white blood                                    Photo: Rick Crompton.
' ·qgments will be determined.                      cells) and enlargement and "distortion" of
                                                                                                       with the best prognosis is "diffuse well­
                                                    the lymph glands .
                                                                                                       differentiated lymphocytic lymphoma".
                                                        In some ways . it is similar to Hodgkins
                                                                                                       Patients with this form of lymphoma, who
                                                    Disease. but the type of lymphocyte affected
                                                                                                       have the " adult" type of the enzyme, live a
         Gentamicin plasmid                         is different and the age of onset differs also.
                                                                                                       long time. Van der Weyden says. " They can
                                                    Hodgkins Disease usually strikes young
                  Chromosom e                                                                          have a normal life-span if the disease can be
                                                    people in the 15-30 age group or the elderly.
                                                                                                       controlled by chemotherapy and
                                                    Non-Hodgkins lymphoma is a disease of
                                                                                                       radiotherapy." he says.
Chloramphenicol plasmid                             middle and later life .
                                                                                                          At the other end of the scale are patients
            (Form 1)                                    The biochemical " marker" isolated by the
                                                                                                       with diffuse histocytic lymphoma who have a
                                                    Monash team , Clinical Associate Professor
                                                                                                       more "prol iferative and prognostically
                                                    M .B. Van der Weyden, Drs P. H. Ellims
Chloramphenicol plasmid
                                                                               unfavorable disease". These patients have
                                                    and T. E. Gan. is an enzyme , thymidine
       (Form 2)
                                                                                       the " foetal" form of the enzyme.
                                                    kinase. which is involved in the multiplication
                                                                                                          There is a whole gradation between. Some
                                                    of cells.
                                                                                                       pat ients, with the " adult" form of the
                                                        If thymidine kinase is present in an "adult"
                                                                                                       enzyme, need not be treated at all. They need
                                                    form in the lymph glands and lymphocytes of
             Cryptic plasmid                                                                           only be watched in case the disease starts to
                                                    patients suffering from non-Hodgkins
                                                                                                       proliferate and the " adult" form of the
                                                    Lymphoma. it is an indication that the
Agarose gel, after staining and illumination with                                                      enzyme is transformed into the "foetal" form.
ultraviolet light, shows bands of "Gorden           tumour is slow-growing and may not even
                                                                                                          The Monash team has studied 45 patients
Staph " DNA , with ptssmtds, which carry genes      need treatment.
for resistance to various antIbIotics. The strain                                                      at the Alfred and Prince Henry 's Hospitals
(left) was Isofated from a patient at the Royar
                                                        If it is present in the "foetal" form. it
                                                                                                       over the past five years. The team has found
Children's Hospital; (r ight) from Prince Henry's   indicates that the tumour is fast -growing and
HospItal.                                                                                              that . while it is not possible to form a
                                                    intensive radiotherapy and chemotherapy is
                                                                                                       prognosis on " established parameters" . such
    These cloned fragments have been used           needed.
                                                                                                       as age . symptoms or bone marrow
     probes to unravel the role of messenger            Van der Weyden and his colleagues have
                                                                                                       involvement. it is possible when the patients
RNA (mRNA) in the "F factor" fragment.              developed a simple test, which can be done
                                                                                                       are divided into groups accord ing to the
mRNA is involved in the manufacture of              in any biochemical laboratory. to detect the
                                                                                                       presence of either the " adult" or "foetal"
protein and the Monash team has shown that          presence of this enzyme in its differing forms.
                                                                                                       forms of the enzyme in their lymph glands
mRNA is made from this region. They are                 The " adult " form utilises adenosine
                                                                                                       and blood sera.
now looking at proteins corresponding to the        triphosphate (ATP) and cytidine triphosphate
                                                                                                          The team found that the group with the
mRNA.                                               in its metabolism. The "foetal" form , which
                                                                                                       "adult" form of thymidine kinase had a mean
    Skurray stresses that there is no danger        indic ates a rapidly developing disease ,
                                                                                                       survival rate in excess of 400 weeks . Where
from the genetic engineering techniques that        utilises only ATP.
                                                                                                       the "foetal" form of the enzyme was present
he is using to map the " F factor" genes.              " W e have demonstrated that there is a
                                                                                                       in the serum or lymphocytes, the mean sur­
    " W hat we are doing is nothing more then       progressive increase in activity of the
                                                                                                       vival rate was one year.
what has occurred previously in nature." he         enzyme. thym idine kinase. as you go from
                                                                                                          The Monash team has found that the
says. " W e are not making any hybrid bacteria      patients with a slowly progressing to a rapid­
                                                                                                       enzyme " marker" is a valuable aid also in the
or creating any combinations that don 't            ly progressing form of the disease ," Van der
                                                                                                       management of chronic lymphocytic
already exist. Furthermore, the E. Coil strain      Weyden says.
                                                                                                       leukaemia . a slowly-developing form of
we are using for cloning is so enfeebled that           The problem of diagnosis and treatment of
                                                                                                       leukaemia which occurs in older people .
it can only exist for a short time in the human     non -Hodgkins Lymphoma is complicated by
                                                    the fact that there are different forms of the        Because of the slowly-developing nature
gut.
                                                                                                       of the disease . the age of onset and the
    " W e are not using recombinant DNA             disease.
                                                                                                       unpleasant side -effects of modern
technology in our work on staphylococci, and            Two major sub-groups have been
                                                                                                       chemotherapy . some doctors have
we have no plans to use it until we know            identified by histological techniques: nodular
                                                                                                       questioned the need for treatment of chronic
more about the plasm ids and the genes they         non-Hodgkins lymphoma, in which the
                                                                                                       lymphocytic leukaemia.
carry."                                             disease is usually disseminated but is slowly
                                                                                                          But the Monash team has identified two
    The staphylococcus and " F factor"              progressing , and diffuse non-Hodgkins
                                                                                                       sub-groups of the disease : one , in which the
research is being funded by Monash Special          lymphoma, in which it is localised but has a
                                                                                                       " adult" form of thymidine kinase is present,
Research funds and the Australian Research          " highly proliferative capacity."
Grants Committee.                                       The form of non-Hodgkins lymphoma                                               Con tin ue d overleaf
MONASH REVIEW                                                            7                                                                            JUNE
                                                                                                      Physiologist Dr Magda Weiss (r ight), ess ist ed by

Hormone                                                                                               technical officer Mrs Val Ford, s ep arati ng
                                                                                                      adrenal zones of the brusti-teited p ossum. She
                                                                                                      has found thal lh e female possum has a special
                                                                                                      zone In the adrenal cortex with a different hor­

clues to                                                                                              mone pattern to that of adult males and im­
                                                                                                      mature an imals.
                                                                                                                                Photo: Rick Crompton .
                                                                                                      tals ," Weiss says, " w ould seem to be a more
marsupial                                                                                             appropriate adaptation, enabling the animal
                                                                                                      to adjust more rapidly to env ironmental
                                                                                                      change. "

evolution                                                                                                 A puzzling feature to emerge from the
                                                                                                      research is the discovery that there is a sex
                                                                                                      and age difference with regard to an enzyme
    AT one time the placental animals ­                                                               which metabolises and inactivates steroids.
the dominant mammalian species - were                                                                 This enzyme , called a reducing enzyme, is
thought to be more advanced on the                                                                    usually found only in the liver . In the possum
evolutionary tree than the marsupials.             hormones [steroids} which are involved in          it is found also in the adrenal gland of the
    The marsup ials ware considered ancestral      salt metabolism and the metabolism of              adult female.
to the placentals,                                 energy reserves.                                       Its activity is very high in the adult female
    The present opinion among evolutionary             Weiss's team found that while the bas ic       possum : it is almost absent in the male pos ­
biologists is that this is most unlikely. They     adreno-cortical funct ions of the marsupials       sum and it is neglig ibly low in immature
favor the view that marsupials and placentals      were similar to those of placental mammals,        animals of both sexes.
have d iverged from a common ancestry.             there were considerable differences                    Weiss says it has long been known that
    In this view, many of the peculiarities of     regarding the properties and activities of the     the possum is unique among species in that
marsupials are specialisations wh ich have         enzymes involved in hormone synthesis and          the female'S adrenal cortex, unlike that of t ~
evolved in isolation . They a re not               in the responses of the hormones to the            male , possesses an additional ar c
characteristi cs that were formerly present in     body 's various regulatory systems.                composed of specific cells referred to as the
the ancestry of placentaIs.                            Some of the endocrine features were            special zone. This special zone is also absent
    The most striking difference between mar­      peculiar to marsupials as a class, such as the     in the adrenals of immature possums.
sup ial and placental mammals is in the way        synthesis of unique steroids , but there were          " The special zone varies in size during the
tha embryo develops.                               also significant interspecies differences.         reproductive cycle , pregnancy and lactation,"
   The marsupial embryo is born in a very              Because the adaptations appeared to be         Weiss says. " At times it can occupy as much
immature form and completes its                    most marked in the brush -tailed possum , she      as 75 percent of the total VOlume of the
development in the mother's pouch.                 has used this marsupial to explain her             gland ."
    In placental animals , on the other hand .     findings.                                              Weiss and her team dissected the special
the foetus is nourished in the uterus, through         "In the early stages of our investigations     zone from the cortex proper to determine
the placenta , until development is far            we discovered that the adrenal venous blood
                                                                                                      steroid synthesis. A remarkable picture
advanced.                                          of the possum contained numerous unusual           emerged.
    Monash physiologist Dr Magda Weiss.            st eroids :' she says. " Som e of these steroids       Wh ile the steroid pattern of the cortex
assisted by technical officer Mrs V. L, Ford       we re intermediates in the biosynthetic            proper was sim ilar in the female possum to
and postgraduate students, has now                 pathway. One stero id (Z1-deoxycortisol) is        that of adult males and immature animals,
discovered endocrine differences between           not found in healthy placental mammals, but        the pattern in the special zone was not. It
marsupials and placentals wh ich are just as       it has been found in patients with a specif ic     produced reduced steroids.
striking, and are important in understanding       enzyme deficiency.                                     "lt is obvious that the female possum has
the marsupial's evolution and adaptation to            "This discovery prompted us to undertake       undergone a unique type of adaptation: '
its environment . Har findings are the result of   in-depth investigations into the properties of     Weiss says. "A specific area of the adrenal
 15 years research on marsupials .                 the enzyme systems involved in steroid syn­        cortex has developed in the female which has
    Weiss and her team studied the                 thesis ."                                          the capacity to metabolise the steroid
functioning of the marsupial's adrenal cortex,         Weiss found that unlike normal placental       formed by the cortex proper .
the outer part of a gland, which , in mammals,     mammals wh ich have multiple enzyme                    " The enzyme responsible may be involved
is related to the animal's ability to adjust to    systems. each of which acts on a specific          in the adrenal control of steroid synthesis and
environmental change.                              steroid substrate [substance], the possum 's       inactivation."
   The adrenals are small glands located           adrenal enzymes are "non-substrate­                    One of her future tasks will be to elucidate
above the kidneys. They are composed of an         specific". They act on any steroid substance       the rote of the enzyme .
inner part. called the medulla, and an outer       supplied to it .                                       "Experimental data so far suggests that
part, called the cortex. The cortex is essential       Weiss believes the multiple enzyme             there is an involvement of the ovaries in the
for the maintenance of life since it produces      systems of the placental mammals give them         control of the size of the zone:' she says.
                                                   an advantage over the marsupials, enabling         " Our research is aiming in that direction.
                                                   finer control of biosynthesis, as well as an in­
Lymphoma                                           dividual response to regulatory systems, and
                                                   prov iding a safeguard if one of the enzymes
                                                                                                          "A more difficult task however will be to
                                                                                                      find out what could be the physiological role
                                                                                                      of these reduced steroids which are
Continued from Page 7                              becomes defective.                                 synthesised only in the adult female pos­
                                                       Placental mammals, apparently, also have       sum.
and the other, in which the "foetal" form of       an advantage in their react ion to en­                 Weiss says some features of the adreno­
the enzyme is present.                             vironmental stress .                               cortical function of the possum seem
    When the "adult" form is present, the              Stress usually induces a rapid rise in the     " inferior" in the evolutionary sense and soma
disease is relatively dormant. Where the           synthesis of steroids. Cortisol is a well-known    are difficult to explain.
" foetal" form is present it is rapid in           "stress" steroid. Increased quantities of cor­         She believes however that they probably
developmant. and, according to Van der             tisol are found in the blood plasma and urine      have a " definit e selective value" which has
Weyden , needs early and intensive                 of people subjected to stress .                    enabled the marsupials to survive in
treatment.                                             Weiss found that in the possum the rate of     conjunction with placenta Is under similar en­
    The Monash research has been published         steroid synthesis was only one hundredth to        vironmental conditions.
in Cancer Research and was funded by the           one thousandth that of placental mammals               The research is funded by an ARGC grant.
Anti-Cancer Council of Victoria and the            and that during stress the rise was sluggish
National Health and Med ical Research Coun ­       and of lesser magnitude than in placenta Is.                 Pnn ted by Stand ard Newspapers for
cil.                                                   "The faster stress response of the placen ­                                 MonaSh University
MONASH REVIEW                                                            B                                                                        JUNE

								
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