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ScienceWeek
SCIENCE-WEEK
SCIENCE-WEEK - Part 1/3
A Free Weekly Digest of the News of Science
April 10, 1998
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All of modern science, all the laboratories and the medals, all
the victors and the vanquished, all of it ought to be dedicated
to the memory of one man: Giordano Bruno.
-- The Editors
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Contents of This Issue:
Part 1:
1. A BREWING DEBATE CONCERNING GERMLINE GENE THERAPY
2. RESEARCHERS SAY DNA PATENTING WILL IMPEDE MEDICAL PROGRESS
3. NEW STUDY FINDS CORPORATE GIFTS IMPLY CORPORATE CONTROL
4. A PROPOSAL IN NEW ZEALAND FOR PRIVATIZATION OF UNIVERSITIES
Part 2:
5. SCULPTURED FACE OF KENNEWICK MAN INCREASES CONTROVERSY
6. NEXT GENERATION SPACE TELESCOPE TO BE LAUNCHED IN 2007
7. ON RECENT DEVELOPMENTS IN SUPERSTRING THEORY
8. ON THE AGGREGATION OF YOUNG GALAXIES IN A DARK-MATTER UNIVERSE
9. ENERGETIC COSMIC RAYS MAY BE IRON NUCLEI
10. ON CHAOS THEORY AND THE STABILITY OF OUR SOLAR SYSTEM
11. COMPLETE GENOME OF A HYPERTHERMOPHILIC BACTERIUM
12. ON THE MOLECULAR MECHANISMS OF SWARMING IN BACTERIA
13. ON RECEPTOR ACTIVATED RETROVIRAL MEMBRANE ASSOCIATION
14. ON DYSLEXIA AND FUNCTIONAL DISRUPTION IN BRAIN ORGANIZATION
Part 3:
15. ON LENTIVIRUS-INDUCED CENTRAL NERVOUS SYSTEM DISEASES
16. IMMUNIZATION AGAINST RABIES WITH PLANT-DERIVED ANTIGENS
17. FURTHER EVIDENCE OF HERPES VIRUS ROLE IN KAPOSI'S SARCOMA
18. LITHIUM ION MECHANISM IN TREATMENT OF MANIA AND DEPRESSION
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1. A BREWING DEBATE CONCERNING GERMLINE GENE THERAPY
In an unsigned editorial, the journal Nature is calling for a
cautious approach to germline gene therapy, procedures that make
changes in the genome of germline cells of an individual rather
than only in somatic cells. Germline cell genome changes are
transmitted to succeeding generations. The editorialist in Nature
says: "The medical and social revolution that the techniques are
likely to bring are of such sweeping significance that it would
be both foolhardy and dangerous to leave the development of the
field to the whim of individuals. We share a collective
responsibility to ensure that such developments take place in an
acceptable manner." The editorial was evidently provoked by a
recent meeting of specialists in the field at the University of
California Los Angeles (US). Most scientists at that meeting
apparently voiced opposition to significant regulation, and James
Watson, head of the Cold Spring Harbor Laboratory (US), evidently
stated that any international attempt to regulate germline
engineering would be "a complete disaster." This is the second
instance within the past few months in which the journal Nature
has called for governmental regulations when such regulations are
opposed by most researchers. The last instance was a call by the
journal Nature for a moratorium on xenotransplantation trials.
(Nature 26 Mar 98)
2. RESEARCHERS SAY DNA PATENTING WILL IMPEDE MEDICAL PROGRESS
Complementary DNA, denoted as cDNA, is DNA that is synthesized in
vitro from an RNA template using the enzyme reverse transcript-
ase, and it can be used in cloning to investigate the presence of
various genes, or as a probe for homologous sequences in various
tissues or species. ... ... Glasner and Rothman (University of
West England Bristol, UK), in a letter to the journal Nature,
tabulate results of a survey of the Human Genome Mapping Project
resource center as an indication of the views of laboratory bench
scientists concerning the legal protection of biotechnological
inventions. This was a UK survey, with 525 respondents, nearly
90% of them located in the UK. Of those surveyed, 86.8% of 508
respondents believe that patenting of partial and uncharacterized
complementary DNA sequences without a knowledge of their
biological function will impede future development of medical
diagnostics and therapeutics.
QY: Harry Rothman (h-rothman@wpg.uwe.ac.uk)
EMAIL
(Nature 26 Mar 98)
-------------------
Related Background:
GENOME PATENTING: THE MERCK EXCEPTION
In the arena of science, a discovery presupposes the preexistence
of something and implies a finding rather than a making, whereas
an invention implies fabricating something useful as the result
of original thought or experiment. In the arena of law, however,
the differences between discovery and invention are often not so
clear. A rather heated and significant debate, for example, has
arisen in recent years concerning the awarding of patents by the
US Patent Office for bits and pieces of the human genome --
certainly found (discovered) material rather than "invented"
material -- the policy ostensibly in place to provide incentive
for commercial biotechnology research, but also providing as a
consequence various proprietary blockades to access of research
material and research data, the blockades being found onerous and
antithetical to the spirit of science by many researchers.
Biotechnology is an infant discipline, and the legal structure
surrounding it is in process of evolution. That much said, it
should also be said that no one is in apparent agreement on
either side about exactly how that evolution should develop.
Recently, a representative of Merck & Co., one of the major
commercial interests in biotechnology research, outlined
Merck's position in a letter in response to a previous published
report on the human genome patenting problem. Merck's position is
apparently that human genome patenting and researcher access to
materials and data are not mutually exclusive, an attitude
supported by many people in biotechnology. But also in the letter
is the following: "Merck does not believe that patents should be
awarded to either genes or expressed sequence tags for which the
function or utility is purely speculative." Which is consistent
with classical US patent law, but which is not entirely
consistent with the attitudes of many commercial and university
research laboratories that hurry to file patents on bits and
pieces of the human genome whose function is indeed not yet
clarified. QY: Alan R. Williamson, Merck Research Labs., Merck &
Co. Inc., Rahway, NJ 07065-0900 US (Science 31 Oct 97)
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CONTINUING PROBLEMS OF GENOME PATENTING
The U.S. decision in the 1980s to allow anyone to obtain patent
rights to parts of the human genome is producing fruits these
days that many biologists are calling rotten. Of concern now are
genetic markers called "single nucleotide polymorphisms". A DNA
polymorphism is a DNA sequence that occurs in the population in
two or more variants, each with a significant frequency of more
than abut 1%. A single nucleotide polymorphism is an alteration
occurring in a single nucleotide base, and the alteration may or
may not be involved in a disease process. What is significant in
this context is that these alterations can be used as markers by
researchers scanning an entire genome for significant mutations.
Many researchers consider single nucleotide polymorphisms so
obvious scientifically that they should not be patentable. But
that is not the current situation, and there is concern that the
U.S. Patent Office is handing out patents in molecular biology
without much understanding of the science involved, the ostens-
ible purpose that of promoting commercial funding of potentially
useful health applications. Most biotechnology companies are
exceedingly happy about this attitude. Abbot Laboratories, for
example, has now announced it will invest up to US$20 million of
equity in a company called Genset (Paris, FR), and support up to
US$22.5 million in research for the purpose of acquiring
proprietary rights to as many single nucleotide markers as
possible. Researchers are concerned that commercial entities will
tie up so many parts of the human genome with patents (there are
about 100,000 genes in the human genome) that no one will be able
to do any substantive research on the human genome without paying
royalties to someone. (Science 19 Sep 97)
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STATISTICS ON U.S. PUBLIC SECTOR PATENTS ON HUMAN DNA
In a correspondence, S. M. Thomas et al (two installations in the
UK) present results of an analysis of patents published in 1995
that include claims for human DNA sequences. 40% of the patents
are from public-sector institutions such as universities, and
most of them from the U.S. This is double the estimate for the
previous decade. The authors call the increase "remarkable".
(Nature 21 Aug 97)
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SCIENTISTS URGE CAUTION IN AWARDING OF HUMAN GENE PATENTS
Continuing the expression of concern about the manner in which
current U.S. intellectual property laws may interfere with
scientific research, the U.S. National Academy of Sciences has
joined the National Institutes of Health and the Human Genome
Organization in protesting an interpretation of current patent
law that would permit the issuing of patents on what are called
"expressed gene sequence tags". Bruce Alberts, president of the
National Academy of Sciences, warns against "patents that allow
an early group of inventors who have disclosed little new
knowledge to constrain the actions of subsequent investigators."
(Nature 26 Jun 97)
-------------------
COMPANY OBTAINS PATENT FOR SKIN CANCER MELANOMA GENE
Under present U.S. and European patent law it is possible to
obtain a patent on a human gene in the same manner as one
obtains a patent on a chemical compound. Myriad Genetics, the
Salt Lake City company that has two patents pending for breast
cancer genes (BRCA-1 and BRCA-2), has now received a patent for
the gene it claims causes melanoma (Multiple Tumor Suppressor 1
or MTS1), and for the method of testing for the presence of that
gene in humans. Lisa Cannon-Albright, a University of Utah
geneticist, Mark Skolnik, a Myriad geneticist, and Alexander
Kamb, a Myriad molecular biologist are listed as the inventors.
(New York Times 5 May 97)
3. NEW STUDY FINDS CORPORATE GIFTS IMPLY CORPORATE CONTROL
Blumenthal et al (2 installations, US) report an anonymous survey
of 2167 scientists working at 50 research-intensive universities
in the US. More than half of the university scientists who
received gifts of research material from pharmaceutical companies
or biotechnology companies report that the donors expect to exert
influence over their work, including review of academic papers
before publication, and retention of patent rights for commercial
discoveries. This is apparently the first study to examine
relations between commercial interests that give gifts of
research materials and the scientists who receive them. Unlike
research grants and contracts, gifts to US scientists are largely
unregulated by universities and are usually dismissed as
insignificant. Christopher Scott, director of research
development for the Stanford University Medical Center, says:
"There has been, in essence, a gray market of research based on
gifts for many, many years."
QY: Christopher Scott, Stanford University 415-723-2300.
(J. Amer. Med. Assoc. 1 Apr 98) (New York Times 1 Apr 98)
-------------------
Related Background:
INTIMIDATION OF RESEARCHERS BY SPECIAL INTEREST GROUPS
A recent issue of the highly respected New England Journal of
Medicine includes a 5 page exchange of letters on the subject of
intimidation of researchers by special interest groups. The
letters concern three different special interest-clinical science
entanglements: 1) a research study of multiple chemical sensit-
ivity; 2) the public health hazard of a marketed chemical
(tryptophan) product; 3) a clinical investigation of the outbreak
of interstitial lung disease among workers in a nylon flocking
plant. The first situation involves an accusation of attacks
against a researcher by special interests opposed to the
researcher's published results; the second situation involves an
accusation of peer review corruption by a large corporate entity
confronted with a billion-dollar damage suit; the third situation
involves an accusation of censorship and harassment of a medical
specialist by a manufacturing plant, a medical school
administration, and a hospital. These are all complicated
entanglements, and one cannot do full justice to them in a few
hundred words. But all parties on both sides of the issues
present their views, and these 5 pages of letters provide a
textbook illustration of the problems existing at the societal
interfaces of science. The letters are in response to an article
on the subject by Richard A. Deyo et al that appeared in NEJM on
April 14, 1997 (336:1176).
QY: R. A. Deyo, Univ. Washington Seattle (206) 543-7212
(New England J. Med. 30 Oct 97)
-------------------
MORE PROBLEMS ARISING FROM CORPORATE-UNIVERSITY RESEARCH TIES
Difficulties with corporate support of university research were
in the news again this week. In general, what is happening is
that legal tangles in patents and licenses are slowing or halting
completely the availability of technology needed in the diagnosis
and treatment of various diseases. Abbott Laboratories and
Perkin-Elmer Applied Biosystems are in a squabble about a new
nucleic acid analyzing machine called TaqMan that holds great
promise for AIDS researchers, and Paul Jung, an organic chemist
at Abbott, was recently stopped by his employer from giving a
scheduled paper on TaqMan at a meeting. In another domain, a
cell-sorting device made by CellPro Inc. of Seattle is being
suppressed by its competitor, the triumvirate Becton Dickinson
and Co., Baxter Healthcare Corp., and Johns Hopkins University.
This device is used to sort healthy stem cells, and is of great
importance for people undergoing cancer chemotherapy. Third, in
the domain of DNA research, Stanford University has evidently
awarded an exclusive license for the manufacture and sale of a
powerful new machine that makes oligonucleotides (short stretches
of the nucleotides that are the building blocks of DNA), and the
company, Protogene (Palo Alto, CA US), which is backed by Life
Technologies (Gaithersburg, MD US), refuses to sell the machine
to anyone. Protogene is apparently interested in maintaining a
price floor in the cost of the oligonucleotides that are
essential for DNA research. (Science 6 Jun 97)
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DUPONT RESTRICTING BASIC RESEARCH USE OF A PATENTED MOUSE
A transgenic mouse is a mouse into which genetic material from
another organism has been transferred, the transferred and
incorporated new mouse genes then being expressed with the
resultant production of specific proteins. In 1990, the
corporation E. I. du Pont de Nemours of Wilmington (DE US)
obtained a patent on all applications of a bipartite technique
involving a bacteriophage gene (Cre) and a DNA binding method
(loxP), the technique allowing fine-scale experimental excisions
of parts of an organism's genome. They also created and bred a
transgenic mouse whose genome contains the Cre sequence, not a
difficult maneuver, but they were the first to do it. This strain
of mouse, coupled with the Cre-loxP technology, has become an
important research tool in molecular genetics, and there are now
apparently protestations by many research laboratories that
DuPont's licenses are too restrictive, dampening research, and
even making it at present extremely difficult to obtain any Cre-
mice at all from mouse-breeding installations. Harold Varmus,
Director of the U.S. National Institutes of Health, is attempting
to negotiate a modus operandi with DuPont, but Varmus says, "The
community really needs to rethink what a patent is for." Du Pont
also has an exclusive license to distribute what is called the
Harvard onco-mouse, a tumor-prone animal much used in cancer
research, and DuPont is attempting to control the use of this
animal as well. (Science 4 Jul 97)
-------------------
DETAILS OF DISCOVERY OF ASTHMA GENE REMAIN A CORPORATE SECRET
Difficulties in the mingling of corporate interests with
scientific research continue to grow in number, perhaps because
the financial stakes are growing. This week Sequana Therapeutics
Inc. (San Diego CA US), in conjunction with collaborators at the
University of Toronto (CA), issued a press release declaring they
had "discovered a gene responsible for asthma", while at the same
time stating that the scientific paper reporting the research was
in the "very early stages" of preparation and might be published
within a year. Sequana is in a financial arrangement with the
pharmaceutical firm Boehringer Ingelheim, and the CEO of Sequana
says no scientific details of the discovery will be revealed
until his company has filed for a patent, the purpose of this to
give Boehringer Ingelheim some "lead time" in commercial
development. The academic collaborators in the project are Arthur
Slutsky and Noe Zamel (University of Toronto CA). Slutsky points
out that the Sequana investment of more than $10 million to find
the gene is more than the Canadian government has spent on the
entire human genome project in the last two years. The price for
the Sequana financial support of the research was apparently
secrecy. (Science 30 May 97)
-------------------
ACADEMIC JOURNAL REVISITS CORPORATE CORRUPTION OF SCIENCE
Lingua Franca, a highly respected general academic journal, has
published a review of some recent history in the arena of
corporate corruption of science and scientific research. The
fundamental problem is simply stated: Some corporations fund
scientific research with expectations, often contractual, of
control of publication and the final wording of conclusions in
the resultant papers. Several prestigious journals still do not
require scientists who report research results to reveal any
connections to interests that might profit from their
conclusions. But most of the scientific community is determined
to put an end to any corruption. The story is still to be played
out. (Lingua Franca June/July 1997)
4. A PROPOSAL IN NEW ZEALAND FOR PRIVATIZATION OF UNIVERSITIES
For the past two decades government policy makers in many
industrialized countries have focused their energies on the
problem of engineering their academic communities to "maximize"
research productivity, and it is evident this engineering effort
is still in progress. In New Zealand, the government has
apparently proposed turning universities into private bodies
"fully exposed to market forces", and with all academics
designated as either teachers or researchers. Apparently, there
has been fierce criticism of the proposal from the academic
community. The idea has been floated in a discussion document
("green paper"), and a policy document ("white paper") is
scheduled to be published later this year. (Nature 26 Mar 98)
(continued in Part 2)
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
SCIENCE-WEEK - Part 2/3
A Free Weekly Digest of the News of Science
April 10, 1998
Contents of Part 2:
5. SCULPTURED FACE OF KENNEWICK MAN INCREASES CONTROVERSY
6. NEXT GENERATION SPACE TELESCOPE TO BE LAUNCHED IN 2007
7. ON RECENT DEVELOPMENTS IN SUPERSTRING THEORY
8. ON THE AGGREGATION OF YOUNG GALAXIES IN A DARK-MATTER UNIVERSE
9. ENERGETIC COSMIC RAYS MAY BE IRON NUCLEI
10. ON CHAOS THEORY AND THE STABILITY OF OUR SOLAR SYSTEM
11. COMPLETE GENOME OF A HYPERTHERMOPHILIC BACTERIUM
12. ON THE MOLECULAR MECHANISMS OF SWARMING IN BACTERIA
13. ON RECEPTOR ACTIVATED RETROVIRAL MEMBRANE ASSOCIATION
14. ON DYSLEXIA AND FUNCTIONAL DISRUPTION IN BRAIN ORGANIZATION
----------------------------------------------------------------
5. SCULPTURED FACE OF KENNEWICK MAN INCREASES CONTROVERSY
The socio-legal controversy concerning the remains of what is
called the Kennewick Man has apparently acquired more heat as a
result of a presentation by an anthropologist of a sculptured
face based on the skull of the fossil. The story is essentially
as follows: In 1996 the skull and other bones of a man apparently
9300 years old was unearthed on the banks of the Columbia River
in southern Washington State (US) near Kennewick. Since there
have been very few other complete human fossils discovered on the
North American continent from that period, anthropologists were
elated at the find, which occurred in territory under the
jurisdiction of the US Army Corps of Engineers. Apparently, there
is a "Native Graves Law" in Washington State that requires
determination of the "race" of any human remains unearthed, and
because of that law a local anthropologist (James Chatters) was
called in to categorize the fossil. Chatters decided the fossil
was "Caucasoid", evidently a debatable category to some anthropo-
logists. But the local Umatilla Indians immediately claimed the
fossil as one of their own and want the remains properly buried,
while another group, the California-based pagan cult Asatru Folk
Assembly, claims the fossil is a white ancestor to modern-day
Europeans and proof that white men came to America before the
Indians. The result is that for the past 19 months there has been
a 4-way legal battle between the Indians, the pagan cult, a group
of research anthropologists, and the US Army over the remains,
which have been locked up from the beginning and are unavailable
for study by anthropologists. Last week a sculptured model of the
face of the Kennewick Man was presented by James Chatters to the
public press, and apparently everyone, including Chatters, agrees
the model looks like Patrick Stewart, the Star Trek actor.
Chatters, in fact, says he had the actor in mind when he had the
face prepared by a sculptor. One is tempted to label the entire
affair "Science as Circus". (New York Times 2 Apr 98)
6. NEXT GENERATION SPACE TELESCOPE TO BE LAUNCHED IN 2007
Anne L. Kinney (Space Telescope Science Institute Baltimore, US)
reviews current plans for the Next Generation Space Telescope
(NGST) that will eventually replace the Hubble Space Telescope
that is currently in orbit and which is scheduled to retire in
2005. The Hubble Telescope has a 2.4 meter mirror, but the plan
is for the next space telescope to have an 8 meter mirror.
Hopefully, the contractor for NGST will be chosen by 2000,
construction will be underway by 2003, and a launch is
tentatively planned for May 2007. The NGST will have 10 times the
light gathering power of the Hubble, will be optimized for the
near infrared part of the spectrum, will not require servicing by
astronauts, and will be a deep-space telescope orbiting Earth in
a distant orbit during a lifetime of approximately 10 years. It
is hoped the new telescope will substantially increase our
understanding of a number of cosmological phenomena.
QY: Anne L. Kinney, Space Telescope Science Institute Baltimore
(US) (Astronomy May 1998)
7. ON RECENT DEVELOPMENTS IN SUPERSTRING THEORY
Bose-Einstein statistics is the statistical mechanics of a system
of indistinguishable particles for which there is no restriction
on the number of particles that may simultaneously exist in the
same quantum energy state. Bosons are particles that obey Bose-
Einstein statistics, and they include photons, pi mesons, all
nuclei having an even number of particles, and all particles with
integer spin. Fermions (electrons, protons, neutrons) are
particles that obey the Pauli exclusion principle: i.e., no two
fermions of the same kind can occupy the same quantum state.
In particle physics, string theory is a theory of elementary
particles based on the idea that the fundamental entities are not
point-like particles but finite lines (strings), or closed loops
formed by strings, the strings one-dimensional curves with zero
thickness and lengths (or loop diameters) of the order of the
Planck length of 10^(-35) meters. The fundamental forces comprise
the gravitational force, the electromagnetic force, the nuclear
strong force, and the nuclear weak force, and the "grand unified
theories" are theories that aim to provide a mathematical frame-
work in which the electromagnetic forces, strong forces, and weak
forces emerge as parts of a single unified force, with the three
forces related by symmetry. Supersymmetry is an aspect of an
extension of the grand unified theories, an attempt to unify all
the four fundamental forces, i.e., linking gravitation to the
electromagnetic force, the strong force, and the weak force
through a supersymmetry scheme, and superstrings are strings in
this scheme that obey supersymmetry. ... ... John H. Schwarz
(California Institute of Technology, US) presents a brief
overview of some of the advances in understanding super-
string theory that have been achieved in the last few years.
String theories that have a symmetry relating bosons and
fermions, called "supersymmetry", are called "superstring"
theories. Major advances in understanding of the physical world
have been achieved during the past century by focusing on
apparent contradictions between well-established theoretical
structures. In each case the reconciliation required a better
theory, often involving radical new concepts and striking exper-
imental predictions. Four major advances of this type were the
discoveries of special relativity, quantum mechanics, general
relativity, and quantum field theory. This was quite an achieve-
ment for one century, but there is one fundamental contradiction
that still needs to be resolved, namely the clash between general
relativity and quantum field theory. Many theoretical physicists
are convinced that superstring theory will provide the answer.
QY: John H. Schwarz, California Inst. of Technology 818-395-6811
(Proc. Natl. Acad. Sci. US 17 Mar 98)
-------------------
Related Background:
ON THE EVOLUTION OF STRING THEORY TO MEMBRANE THEORY
... Membrane theory (M-theory) is a recent extension of string
theory in which the fundamental physical entities are considered
as surfaces in a many-dimensional space (membranes) rather than
as lines or loop elements (open or closed strings). Given all of
the above, some caution is necessary: the translation of a highly
abstract mathematical model of physical reality into non-mathem-
atical language is often an exercise of limited usefulness, and
in this case in particular, we are presenting only the ghost of
the theoretical scheme. String theory was originally invented in
the 1960s as a theory of the strong force, became overshadowed by
the strong force theory of gluons and quarks, then had a revival
in the 1980s -- but with the history more dependent on new work
than on fashion. ... ... M. Duff (Texas A & M Univ., US), who is
active in string theory and membrane theory, in a review of
various aspects of the history and essentials of string theory
and membrane theory, suggests that future historians may judge
the 20th century as "a time when theorists were like children
playing on the seashore, diverting themselves with the smoother
pebbles or prettier shells of superstrings, while the great ocean
of M-theory lay undiscovered before them." QY: Michael J. Duff,
Texas A & M Univ., Dept. Physics 409-847-9451
(Scientific American February 1998)
8. ON THE AGGREGATION OF YOUNG GALAXIES IN A DARK-MATTER UNIVERSE
The term "semi-analytic modeling" refers to a quantitative
modeling procedure in which empirical data are used in places to
fix the values of parameters or functions, rather than deriving
these from theoretical principles. N-body simulations, which
usually require extraordinary computational resources, are
simulations involving calculations of interactions of a large
population of entities. "Dark matter", which is thought to
comprise as much as 90% or more of the mass of the universe, is
undetectable except by gravitational effects, and "cold dark
matter" refers to dark matter particles created with low velocity
dispersions in the early universe. At the present time, computer
simulations and empirical observations of galaxy clustering favor
the idea that most dark matter in the universe is cold dark
matter. ... ... Governato et al (7 authors at 3 installations, UK
DK US) report the use of a combination of theoretical techniques
(semianalytic modeling and n-body simulations) to show that large
concentrations of young galaxies (i.e., galaxies in existence
when the universe was one-tenth of its current age) should be
quite common in a universe dominated by cold dark matter, and
that such galaxy concentrations are the progenitors of the rich
galaxy clusters seen today. The authors suggest these clustering
properties of primeval galaxies will be compared with data
collected in the near future, and that the comparison will be a
test of our current understanding of galaxy formation within the
framework of a universe dominated by cold dark matter. QY: C.S.
Frenk (c.s.frenk@durham.ac.uk)
EMAIL
(Nature 26 Mar 98)
9. ENERGETIC COSMIC RAYS MAY BE IRON NUCLEI
The cosmic microwave background is black-body radiation (the
emission radiation of a perfect absorber of radiation) at a
present temperature of 2.73 degrees Kelvin, and has an almost
equal intensity in all directions in space. (The deviations from
isotropic intensity, however, are of extreme importance in
theoretical cosmology.) Infrared radiation is electromagnetic
radiation lying between the radio and the visible bands of the
spectrum (and intermediate in energy between these bands), and
important sources of cosmic infrared radiation are the shells of
dust grains surrounding stars, the shells heated by the star's
visible and ultraviolet radiation. Cosmic rays are particles with
a distant and often extra-galactic origin; they strike the
Earth's atmosphere and produce a shower of new particles detected
on the Earth's surface. One important question in cosmic ray
physics is why there should be so many events with total energies
above 10^(20) eV. The problem is that if a primary particle were
journeying from a distant galaxy, the energy of the particle
ought to be sapped by interactions with cosmic microwave
background photons or with infrared background radiation. There
is the additional problem of how cosmic rays with even higher
energies could have been accelerated to such initial energies in
the first place. ... ... Now Floyd Stecker (Goddard Space Flight
Center, US) has evidently determined that a particle with an
energy of 2 x 10^(20) eV that started out as an iron nucleus
could indeed negotiate a 300-million-light-year journey through
the infrared background radiation. The nucleus would partially
disintegrate en route, but would still arrive at Earth with the
energy of cosmic rays. QY: Floyd Stecker, Goddard Space Flight
Center, US.
(Phys. Rev. Lett. 2 Mar 98) (Amer. Inst. Phys. Bulletin #364)
10. ON CHAOS THEORY AND THE STABILITY OF OUR SOLAR SYSTEM
Ordinarily, a physical system is a system in which future states
can be predicted from prior states. But not all physical systems
exhibit such predictability. The term "chaos theory" refers to a
theory of unpredictable behavior arising in a system that obeys
deterministic laws but exhibits unpredictability. The essential
idea is that in certain systems small perturbations may produce a
cascade of larger perturbations, so that eventually the behavior
of such systems cannot be predicted from prior states no matter
if the systems appear simple and obey deterministic laws.
... ... Adam Frank (University of Rochester, US) reviews
considerations of our solar system in terms of chaos theory. The
solar system may have lost several planets, and Mercury or Mars
might be the next planets to be ejected from their orbits.
Mercury has a small but finite chance of being ejected after a
close encounter with Venus. The essential idea is that due to the
gravitational influence of the other planets, the orbit of a
planet may become more and more eccentric over time, finally
cross the orbit of another planet, with the less massive planet
ejected from the solar system. There is a slight possibility that
the orbit of Mars will someday cross the orbit of Earth, with
Mars ejected from the solar system because of its lower mass. The
author suggests that under the influence of chaos theory our
understanding of planetary motion has been considerably trans-
formed, and the solar system is no longer viewed as a stable
clock, but rather as a dynamic and infinitely complex entity.
QY: Adam Frank, Univ. of Rochester, Dept. of Physics 716-275-4356
(Astronomy May 1998)
11. COMPLETE GENOME OF A HYPERTHERMOPHILIC BACTERIUM
In evolutionary biology, the term "divergence" refers to the
manifestation of new genetic characteristics in a subpopulation
of a species when the subpopulation has become separated from the
larger population by physical barriers -- new genetic character-
istics appearing as the organism adapts to new conditions.
Thermophiles are microorganisms that thrive under conditions of
high temperature such as those in hot springs and deep ocean
vents. "E. coli" refers to the bacterium Escherichia coli, a rod-
shaped intestinal organism that has been used extensively in
research. ... ... Deckert et al (15 authors at 4 installations,
US DE) report the complete genome sequence of Aquifex aeolicus.
The organism is apparently one of the earliest to diverge, and is
one of the most thermophilic bacteria known. It can grow on
hydrogen, oxygen, carbon dioxide, and mineral salts, and at 95
degrees centigrade. The complete genome is one-third the size of
the E. coli genome, with 1,551,335 DNA base pairs. The authors
suggest that the large number of diverse genome sequences of
various biological organisms that will become available in the
future will allow more detailed correlation of global genomic
properties with particular physiologies.
QY: Ronald V. Swanson (rswanson@diversa.com)
EMAIL
(Nature 26 Mar 98)
12. ON THE MOLECULAR MECHANISMS OF SWARMING IN BACTERIA
Flagella are whiplike extensions from certain types of cells, and
in bacteria that have them, they are responsible for locomotion
of the organism. The term "chemotaxis" refers to the movement of
cells in response to chemical stimuli, and in the context of this
report, "chemoreceptors" are the receptors on the surfaces of
mobile cells that initiate the chemotactic response. Substances
that produce chemotaxis are called "chemoeffectors". In bacteria,
"swarming" is an organized surface translocation on solid media
that depends on extensive flagellar activity and cell-cell
contact. Previous studies of bacteria that swarm have indicated
the chemotaxis system is involved, but the mechanism is not
known. ... ... Now Burkhart et al (University of Texas Austin,
US) report that two of the four chemoreceptors in E. coli can
support swarming individually, but sensing their most powerful
chemoattractants (serine, or aspartate, or maltose) is not
necessary for swarming. The authors suggest that during swarming,
the chemoreceptors signal through the chemotaxis pathways and
induce swarmer cell differentiation (e.g., increased number of
flagella) in response to still unknown signals other than their
known chemoeffectors.
QY: Rasika M. Harshey (rasika@uts.cc.utexas.edu)
EMAIL
(Proc. Natl. Acad. Sci. US 3 Mar 98)
13. ON RECEPTOR ACTIVATED RETROVIRAL MEMBRANE ASSOCIATION
Retroviruses are single-stranded RNA viruses that have an enzyme
called reverse transcriptase, and with this enzyme the viral RNA
is used as a template to produce viral DNA from cellular
material. This DNA is then incorporated into the host cell's
genome, where it codes for the synthesis of viral components.
Envelope proteins are the proteins found in the envelopes of
viruses in their virion stage (i.e., the entire virus as it
exists before or after the replication phase). Liposomes are
laboratory created vesicles (spherules) in which the lipid
molecules are spontaneously arranged into bilayers with
hydrophilic groups exposed to water molecules both outside the
vesicle and in the core. Rous sarcoma virus is a cancer-producing
virus that infects birds, discovered by Francis Peyton Rous
(1879-1970) in 1911, and the first discovered tumor-producing
virus. In 1966, Rous shared the Nobel Prize in Medicine and
Physiology for this work. Current models of the entry of
retroviruses into host cells propose conformational changes in
the envelope protein of the virus as a precursor to fusion of the
virus with the host cell membrane. ... ... Damico et al (3
authors at University of Pennsylvania, US) report the use of a
cell-free liposome-binding assay to study the behavior of a model
virus envelope protein (from Rous sarcoma virus). In the presence
of purified viral receptor, the viral envelope protein apparently
converts from a water-soluble form to a liposome membrane-
associated form, which is consistent with the conversion of the
envelope protein to its fusogenic state (the state involving
fusion with the host cell membrane). The authors suggest their
results provide direct evidence that receptor binding triggers
conversion of the virus envelope protein to a membrane-fusing
form, and illustrates that Rous sarcoma virus is a useful model
for the study of retroviral entry.
QY: Paul Bates (pbates@mail.med.upenn.edu)
EMAIL
(Proc. Natl. Acad. Sci. US 3 Mar 98)
14. ON DYSLEXIA AND FUNCTIONAL DISRUPTION IN BRAIN ORGANIZATION
Dyslexia is impaired reading ability when the reading competence
is below that expected from the individual's general intelligence
and there is no impairment of vision. It has been proposed that
dyslexic children and adults lack phonologic awareness, an
awareness that strings of letters (orthography) are connected to
corresponding units of speech (phonologic constituents) that they
represent. In biology, magnetic resonance imaging is a technique
involving images produced by mobile protons of a tissue excited
by the application of a magnetic field, and when used in funct-
ional cerebral imaging, the basis of the technique is that it
images very small metabolic, blood-flow, and perfusion-diffusion
changes in vivo, in real time, and with no risk to the subject,
with the essential idea of mapping activity in the brain in
response to external stimuli or during sensory, perceptual, or
cognitive events. ... ... Now Shaywitz et al (15 authors at 2
installations, US) report a study to find the location and extent
of the functional disruption in neural systems that underlies
dyslexia. Functional magnetic resonance imaging was used to
compare brain activation patterns in dyslexic and nonimpaired
subjects as they performed tasks that made progressively greater
demands on phonologic analysis. Brain activation patterns
differed significantly between the groups, with dyslexic readers
showing underactivation in certain specific brain areas and
overactivation in other specific brain areas. The authors suggest
their results support a conclusion that the impairment in
dyslexia is phonologic and that brain activation patterns may
provide a neural signature for this impairment.
QY: Sally E. Shaywitz (sally.shaywitz@yale.edu)
EMAIL
(Proc. Natl. Acad. Sci. US 3 Mar 98)
(continued in Part 3)
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
SCIENCE-WEEK - Part 3/3
A Free Weekly Digest of the News of Science
April 10, 1998
Contents of Part 3:
15. ON LENTIVIRUS-INDUCED CENTRAL NERVOUS SYSTEM DISEASES
16. IMMUNIZATION AGAINST RABIES WITH PLANT-DERIVED ANTIGENS
17. FURTHER EVIDENCE OF HERPES VIRUS ROLE IN KAPOSI'S SARCOMA
18. LITHIUM ION MECHANISM IN TREATMENT OF MANIA AND DEPRESSION
----------------------------------------------------------------
15. ON LENTIVIRUS-INDUCED CENTRAL NERVOUS SYSTEM DISEASES
The term "homeostasis" refers to a physiological equilibrium
necessary in general for the viability of an organism, and in
particular for the operation of many cellular functions.
Homeostatic mechanisms in biological systems usually involve an
element of negative feedback signaling. In vertebrates, for
example, when blood temperature is too high, temperature
receptors provoke a sequence of events involving many pathways
that ultimately results in a lowering of body temperature.
Similar homeostatic mechanisms operate at cellular levels.
Lentiviruses are a subfamily of retroviruses and they produce a
variety of animal and human diseases. Feline immunodeficiency
virus (FIV) is a lentivirus of domestic cats that causes a
spectrum of diseases remarkably similar to AIDS in HIV-infected
humans. Both viral infections induce neurological disorders.
Astrocytes are a type of nervous system "housekeeping cell"
(i.e., involved in metabolic and chemical homeostatic functions,
and not in electrical signal processing) found in the central
nervous system, and they are apparently essential for maintaining
central nervous system homeostasis. ... ... Now Yu et al (3
authors at Scripps Research Institute, US) report a study of the
effect of FIV infection on feline astrocyte cultures, and their
results indicate that infection with FIV significantly decreases
the ability of astrocytes to scavenge extracellular glutamate (a
neurotransmitter that must be "scavenged" to prevent nerve cell
dysfunctions). The effects of FIV infection appear to be
interference with specific biochemical pathways rather than a
result of general toxicity. The authors suggest that a chronic
low-grade infection of astrocytes may impair the ability of these
cells to maintain homeostasis of the central nervous system, and
that this may contribute to one or more neurodegenerative disease
process often associated with lentivirus infections.
QY: T.R. Phillips (tphillips@scripps.edu)
EMAIL
(Proc. Natl. Acad. Sci. US 3 Mar 98)
16. IMMUNIZATION AGAINST RABIES WITH PLANT-DERIVED ANTIGENS
A "recombinant" organism is an organism whose genome has been
modified by the introduction of foreign genetic material. The
peritoneum is the sac that lines the abdominal cavity, and in
this report, the phrase "immunized intraperitoneally" refers to
an injection into the abdominal cavity. In the general sense, an
"antigen" is any chemical entity that produces a response of the
immune system. Increasing knowledge of the molecular biology of
plant viruses has raised the possibility of using these viruses
as antigen expression systems. Unlike conventional recombinant
vaccines, which are largely derived from live-recombinant, live-
attenuated, or killed pathogens, plant viruses are generally
recognized to be nonpathogenic in humans and other animals.
... ... Modelska et al (8 authors at Thomas Jefferson University,
US) report that mice immunized intraperitoneally or orally (by
gastric intubation or by feeding on virus-infected spinach
leaves) with engineered plant virus particles containing rabies
antigen mount a local and systemic immune response. The generat-
ion of the observed immune responses did not require use of
additional immune-system-provoking substances (adjuvants). The
authors suggest these results support the potential of plants as
oral delivery vehicles and plant-produced antigens as vaccine
material.
QY: Vidadi Yusibov (vyusibov@reddi1.uns.tju.edu)
EMAIL
(Proc. Natl. Acad. Sci. US 3 Mar 98)
17. FURTHER EVIDENCE OF HERPES VIRUS ROLE IN KAPOSI'S SARCOMA
Kaposi's sarcoma is a human cancer of skin cells (and sometimes
cells of certain internal tissues), appearing for the most part
in elderly men or in younger men with compromised immune systems.
The disease was first described by the Hungarian dermatologist
Moritz Kaposi (1837-1902). ... ... Martin et al (6 authors at 3
installations, US) report a study of human herpes virus type 8
(HHV-8). The prevalence of HHV-8 infection is high among
homosexual men, correlates with the number of homosexual
partners, and is temporally and independently associated with
Kaposi's sarcoma. The authors suggest their observations are
further evidence that HHV-8 has an etiological role in Kaposi's
sarcoma and is sexually transmitted among men, and that
understanding the epidemiology of HHV-8 is a critical first step
in designing interventions to decrease the transmission of this
pathogen. QY: Dean H. Kedes, Univ. of Calif. San Francisco 415-
476-4044. (New England J. Med. 2 Apr 98)
-------------------
Related Background:
HERPES VIRUS MOLECULAR MIMICRY AND AUTOIMMUNE DISEASE
An autoimmune disease is one of a large group of diseases
characterized by cells of the immune system attacking other cells
of the body, in effect failing to recognize these other cells as
"friendly". Antigens are chemical moieties, often proteins, that
provoke immune responses, and the "epitope" is the small region
of the antigen apparently involved in binding or recognition of
the antigen. T-cells, of which there are various types, are
aggressive immune system cells, first formed in bone marrow, then
maturing in the thymus gland [hence: T(hymus)-cell]. A keratitis
is an inflammation of the cornea, and stromal keratitis is an
inflammation of the connective tissue framework of the cornea.
Invasion of the corneal stroma by herpes simplex virus is one of
the possible consequences of herpes simplex infection. Viral
infection is sometimes associated with the initiation or exacer-
bation of autoimmune disease, although the underlying mechanisms
have been unclear. One proposed mechanism is that viral chemical
moieties that mimic host antigens trigger certain T-cells to
destroy host tissue. ... ... Zhao et al (5 authors at 2 install-
ations, US) report that an epitope of a coat protein of herpes
simplex virus type 1 (KOS strain) is recognized by autoreactive
T-cells that target corneal antigens in a mouse model of auto-
immune herpes stromal keratitis. Mutant viruses that lacked this
epitope did not induce autoimmune disease. The authors suggest
that expression of molecular mimics can influence the development
of autoimmune disease after viral infection. QY: Zi-Shan Zhao,
Dept. of Pathology, Harvard Univ. Medical School 617-432-1550
(Science 27 Feb 98)
-------------------
HERPES VIRUS AS A VIRAL ONCOGENE AND ANGIOGENESIS ACTIVATOR
Kaposi's sarcoma is an ordinarily rare cancer that can be common
in humans with compromised immune systems (for example, in AIDS),
and the herpes viruses are a class of viruses producing the
complex of herpes diseases, some of which are sexually transmit-
ted diseases clinically associated with AIDS. In cell biology,
the term "receptor" denotes a cell surface chemical entity,
usually a protein, that interacts with messenger molecules (e.g.,
hormones) in the extracellular solution. G-proteins are a family
of signal-coupling proteins that act as intermediaries between
activated cell receptors and effectors, for example, the trans-
duction of hormonal signals from the cell surface to the cell
interior. The G-protein is apparently embedded in the cell
membrane with parts exposed on the outside surface and inside
surface. The outside moiety is activated by the first messenger,
and the inside moiety activates the second messenger (which
begins a cascade of signals in the interior of the cell), the G-
protein thus acting as a trans-membrane signal transducer. In the
context of this report, the term "transformation" refers to the
conversion of normal cells into malignant cells exhibiting
uncontrolled growth and loss of functional specialization
(dedifferentiation). Angiogenesis, the origin and development of
blood vessels, is an important consideration in the growth of
cancerous tumors, since the tumor provokes directed angiogenesis
into itself with the end result that the tumor is supplied with
oxygen and nutrients. Without angiogenesis, tumors can attain
only a small size before becoming self-inhibiting. A cytokine is
any substance that promotes cell growth and cell division, and an
inflammatory cytokine is a cytokine involved in the inflammatory
response to tissue injury and infection. As a promoter of cell
growth and division, a cytokine acts as a messenger to cells, and
the transmission of the message requires a binding of the
cytokine molecule to a cytokine-specific receptor on the cell
surface. This receptor is either a protein or a protein complex
or a part of a protein. The lymphatic system is a complex network
for the distribution of lymph fluid (which is similar to blood
plasma -- blood without red cells), and lymphoma is a general
term for a tumor (benign or malignant) of tissue of the lymphatic
system. Bais et al (10 authors at 2 installations, US) report
that signaling by the Kaposi's sarcoma-associated herpes virus G-
protein-coupled receptor leads to cell transformation and tumor
growth, and activates angiogenesis by mechanisms similar to those
produced by inflammatory cytokines. The authors suggest this is
the first demonstration that a Kaposi's sarcoma-associated
herpes virus gene is capable of inducing both transformation and
angiogenesis, and that this evidence strongly supports the idea
that Kaposi's sarcoma-associated herpes virus infection plays a
direct role in Kaposi's sarcoma pathogenesis and lymphoma-
genesis. QY: Enrique A. Mesri
(Nature 1 Jan 98)
-------------------
HERPES VIRUS LINKED TO MULTIPLE SCLEROSIS
In the vertebrate central nervous system, the axons of nerve
cells involved in physiological functions that require rapid
signaling (for example, the neural control of voluntary muscle)
are wrapped in a special sheath called myelin. The myelin sheath
consists of concentric layers of electrically insulating lipid
material, but the sheath is periodically interrupted, and at the
points where the sheath is interrupted so is the electrical
insulation interrupted. The result, predictable from the class-
ical physics of electrical transmission lines and the electrical
parameters of nerve fibers, is that the propagation of an electr-
ical pulse along such nerve fibers occurs at a velocity much
higher than that found in unmyelinated fibers. Multiple sclerosis
is a human disease characterized by the progressive loss of the
myelin of the brain and spinal cord, with the physiological
disruptions to be expected from such loss, considering the
significance of myelin in the functioning of nerve cells. The
herpes viruses are a class of viruses producing the complex of
herpes diseases, and HHV-6 is a recently discovered strain of
herpes virus that apparently causes an infant and early childhood
disease called roseala infantum. Jacobson et al (National
Institutes of Health, US) report that a study of multiple
sclerosis patients (36 patients and 66 controls) revealed that
70% of these patients were infected with the strain of herpes
virus HHV-6. They also report that magnetic resonance imaging
detected numerous myelin lesions in the brain of a deceased
multiple sclerosis patient, and an autopsy revealed HHV-6 in the
lesions but not in the adjoining normal tissues. Some multiple
sclerosis specialists are expressing reservations about the
interpretation of these results, stating it is possible the viral
infection is a consequence rather than a cause of multiple
sclerosis. QY: Steven Jacobson, National Institute of
Neurological Disorders and Stroke, NIH, Bethesda, MD 20892-0148
(Nature Medicine December 1997)
-------------------
INCREASING U. S. PREVALENCE OF HERPES SIMPLEX VIRAL DISEASE
Genital herpes (also called HSV-2) is a predominantly sexually-
transmitted viral disease caused by the herpes simplex virus. The
disease produces recurrent and often painful skin and internal
lesions, and at the present time there is no cure and only limit-
ed treatment with drugs (e.g., acyclovir). Douglas T. Fleming et
al (7 authors at U.S. Centers for Disease Control and Emory
University, US), examining serological studies of 1976 to 1980,
and new serological studies of 1988 to 1994, report that the
prevalence of HSV-2 infection in the U.S. has increased by 30%
since the late 1970s, and HSV-2 antibody is now detectable in
about 20% of the population over 12 years of age. The authors
suggest that improvements in the prevention of HSV-2 infection
are needed, particularly since such infections, via the genital
ulcers produced, facilitate the transmission of the human immuno-
deficiency virus (HIV), the pathogen in AIDS. QY: Michael E. St.
Louis, CDCP, Mailstop E-02, 1600 Clifton Rd., Atlanta, GA 30333
US (New England J. Med. 16 Oct 97)
-------------------
VIRUSES IN NORMAL CELLS MAY DRIVE GROWTH OF TUMOR CELLS
The idea that viruses are implicated in cancer has existed for
decades, and indeed in a few types of malignancy a related virus
has been identified. But the thinking has always been that if a
virus is implicated in cancer, it is because it invades a cell
type, corrupts the cell's genetic machinery, and the result is a
wild cell that rapidly proliferates. Now a new scheme has
appeared, reported by M. B. Rettig et al (various installations
in Los Angeles, including the University of California Los
Angeles; US). What they have found is that in cases of the human
cancer multiple myeloma, healthy neighboring dendritic cells in
human bone marrow are infected with Kaposi sarcoma-associated
herpes virus, and that this virus is orchestrating the production
by these healthy cells of interleukin-6, a protein which is known
to stimulate myeloma growth. What is striking, is that the virus
does not infect the malignant cells. If these results are
independently confirmed, there will be an intense new interest in
the possibility of viral promotion of various human malignancies.
(Science 20 Jun 97)
18. LITHIUM ION MECHANISM IN TREATMENT OF MANIA AND DEPRESSION
Manic-depressive illness (also called "bipolar" illness or
bipolar disorder or bipolar depression) is a mental disorder
characterized by severe mood swings ranging from mania to severe
depression. Ionic lithium is the most commonly used drug for the
treatment of manic-depressive illness, but the precise mechanism
underlying its clinical efficacy remains unknown. The hippocampus
is a deep brain structure involved in learning, memory, and
emotion. Glutamate is a major excitatory amino acid neurotrans-
mitter (transmitter substance at synapses) in the brain, involved
in about 40% of all brain activity. "Glutamatergic" neurons are
neurons that secrete glutamate as a neurotransmitter.
... ... Now Nonaka et al (3 authors at 2 installations, US)
report that long-term exposure to lithium chloride dramatically
protects cultured rat cerebellar, cerebral cortical, and
hippocampal neurons against glutamate-induced cyto-toxicity. This
glutamate-induced cytotoxicity apparently involves apoptosis
mediated by N-methyl-D-aspartate (NMDA) receptors. The authors
suggest that modulation of glutamate receptor hyperactivity is at
least part of the molecular mechanism by which lithium alters
brain function and exerts its clinical efficacy in the treatment
for manic depressive illness, and that these actions of lithium
indicate that an abnormality of glutamatergic neurotransmission
should be investigated as a possible pathogenic mechanism
underlying bipolar illness. QY: De-Maw Chuang, US Nat. Inst. of
Health, Bethesda MD 20892-0148
(Proc. Natl. Acad. Sci. US 3 Mar 98)
---------------------------------------------
BOOK NOTES:
R.A. Lockshin et al (eds.): WHEN CELLS DIE
A Comprehensive Evaluation of Apoptosis and Programmed Cell Death
Wiley, 1998, 528p, US79.95
A cross-discipline introduction to cell death research.
Emphasizes the importance of cell death in development,
homeostasis, aging, and disease. Recent information and data;
themes and approaches to cell death; cell death where mitosis is
high and evanescence desirable; cell-death in long-lived cells;
clinical relevance of apoptosis.
D. Merritts et al: ENVIRONMENTAL GEOLOGY
An Earth Systems Approach
W.H. Freeman, 1998, 550p, UK24.95
An introduction to geophysical science focusing on environmental
issues and using the Earth systems approach. A summary of
critical environmental issues, including the effects of natural
events and human intervention.
T. Mikkelson et al: BRAIN TUMOR INVASION
Biological, Clinical, and Therapeutic Considerations
Wiley, 1998, 480p, US99.95
A review of the subject. Chemical carcinogenesis, growth factors,
oncogenes, tumor suppressors, and other biological mechanisms
involved in ability of gliomas to metastasize in the central
nervous system. New anti-invasive therapeutic strategies.
W.K. Purves et al: LIFE
The Science of Biology
W.H. Freeman/Sinauer, 1998, 1250p, UK26.50
5th edition with CDROM.
An introduction to the entire field of biology at an affordable
price. Extensively illustrated. Intended primarily as a teaching
text.
Brian Silver: THE ASCENT OF SCIENCE
Oxford Univ., 1998, 534p, US35 UK25
A journalistic account of the emergence of scientific ideas. The
recently deceased author was a physical chemist.
C. Cohen-Tannoudji et al: ATOM-PHOTON INTERACTIONS
Wiley, 1998, 680p, US44.95
A treatment of the physics governing the interactions between
light and matter. Emission, absorption, and scattering of
photons; perturbation methods; resolvent method; use of master
equation. The first author is a Nobel Laureate in Physics.
---------------------------------------------
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