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PubMed1975

Observations of de novo clones of cytogentically aberrant cells in primary fibroblast cell strains from phenotypically normal women.

In a recent study of chromosome breakage frequencies in 36 primary fibroblast cell strains derived from skin from 10 phenotypically normal women, we observed seven different clones of cells having consistent chromosomal abnormalities. Five of the stem lines were noted in cultures from "control" women and two in fibroblasts from women taking oral contraceptives. We observed aneuploid clones as well as stem lines bearing structural abnormalities (e.g., translocation, inversions). The various aberrant clones were found in cultures ranging in age from 41 to 144 days and comprised varying percentages of the cell populations ranging from 0.8% to virtually 100%. The possible evolution in culture of clones of cells having aberrant karyotypes should be considered in interpreting findings from fibroblast cultures initiated for clinical evaluation.

Cell Division↗
PubMed1998

Isolation of an Escherichia coli K-12 mutant strain able to form biofilms on inert surfaces: involvement of a new ompR allele that increases curli expression.

Classical laboratory strains of Escherichia coli do not spontaneously colonize inert surfaces. However, when maintained in continuous culture for evolution studies or industrial processes, these strains usually generate adherent mutants which form a thick biofilm, visible with the naked eye, on the wall of the culture apparatus. Such a mutant was isolated to identify the genes and morphological structures involved in biofilm formation in the very well characterized E. coli K-12 context. This mutant acquired the ability to colonize hydrophilic (glass) and hydrophobic (polystyrene) surfaces and to form aggregation clumps. A single point mutation, resulting in the replacement of a leucine by an arginine residue at position 43 in the regulatory protein OmpR, was responsible for this phenotype. Observations by electron microscopy revealed the presence at the surfaces of the mutant bacteria of fibrillar structures looking like the particular fimbriae described by the Olsén group and designated curli (A. Olsén, A. Jonsson, and S. Normark, Nature 338:652-655, 1989). The production of curli (visualized by Congo red binding) and the expression of the csgA gene encoding curlin synthesis (monitored by coupling a reporter gene to its promoter) were significantly increased in the presence of the ompR allele described in this work. Transduction of knockout mutations in either csgA or ompR caused the loss of the adherence properties of several biofilm-forming E. coli strains, including all those which were isolated in this work from the wall of a continuous culture apparatus and two clinical strains isolated from patients with catheter-related infections. These results indicate that curli are morphological structures of major importance for inert surface colonization and biofilm formation and demonstrate that their synthesis is under the control of the EnvZ-OmpR two-component regulatory system.

Alleles↗
PubMed1994

[Ethological analysis of behavior and the emergence of ethics].

The problem of the emergence of ethical conduct is considered in the perspective of the neo-darwinian scheme and thus of the survival value of actions complying to this definition. After a brief recall of basic ethological principles, the applications of the cultural character to certain behaviour patterns of primates is analysed and introduces the concept of value. The emergence of symbolic and reflexible language in the course of the evolution of the ancestors of Homo sapiens is discussed. The ethical order is defined as a code liable to qualify actions which were originally programmed. The consequences of this duality of codes governing a same action are discussed.

Animals↗
PubMedDate not supplied

Analogy between training for dancers and problems of adjustment to microgravity: an evaluation of the subjective vertical in dancers.

"Moderne dance" (as opposed to a more academic or classical dance form) uses techniques from kinesiology, anatomy and improvization which are adapted to a cultural, technological and political environment. The function of a choreographic system is to take and give a measure of the world. This includes, with the present tendency of the evolution of culture, a new "naturalism" which seeks the secrets of the body. Dance movements express in terms of space the dimension fo the infinite. It gives somehow the measure of a world within which everything is relative. Except for the speed of light, time and space are bound together by the same principle. The qualities of body awareness and specific motricity in dancers imply--besides a strict discipline--balance, coordination, muscular performance and perfect orientation, problems that astronauts also encounter in microgravity. Could chosen exercises used in modern dance technique be applied to the training of astronauts? Dancer-choreographer Kitsou Dubois has been working in this direction since 1988. She was granted a "Villa Medicis Hors Les Murs" by the French Ministry of Foreign Affairs, to carry on with her research at NASA, Houston, Tex. in April 1989. It allowed her to investigate the reality of this analogy. She intends to evaluate the dancers' subjective vertical refering to Mittelstaedt's observations on the proportional relationship between "space sickness" and some astronauts poor evaluation of the subjective vertical. This study should create a relationship between a choreographer's empirical intuition and a scientific reality.

Adaptation, Physiological↗
PubMed2006

Parallel factor analysis combined with PLS regression applied to the on-line monitoring of Pichia pastoris cultures.

Various key variables (biomass, substrate and product) of bioprocesses should be monitored in order to retrieve useful information on the system, with the biomass (the cell density) the principal target. Although several analytical methods have been adapted and used to monitor the evolution of cell density evolution in cultures, a general method for performing this determination has not yet been established, as each technique has its own advantages and drawbacks. In the present work, noninduced glycerol batch cultures (for which biomass and substrate are the key variables) were monitored using multiwavelength fluorescence spectroscopy. The data gathered were modelled via PARAFAC-PLS chemometric methodologies, resulting in important qualitative and quantitative information about the behaviours of different biogenic fluorophors in batch cultures of the yeast Pichia pastoris. This information was used to predict the target process variables in such cultures; this permitted the applicability of this combined technique to bioprocess monitoring to be assessed.

Biomass↗
PubMed1986

Gene-culture coevolution of complex social behavior: human altruism and mate choice.

The hypothesis is examined that genes bias the development of complex social behavior in one direction over alternatives. Studies of altruism and political attitudes in twins estimate that approximately 50% of the variance is associated with direct genetic inheritance, virtually 0% with the twin's common family environment, and the remainder with each twin's specific environment. Studies of human marriages show that spouses choose each other on the basis of similarity, assorting on the most genetically influenced of a set of homogeneous attributes. These data imply a genetic canalization of social influences such that, within the constraints allowed by the total spectrum of cultural alternatives, people create environments maximally compatible with their genotypes.

Altruism↗
PubMed2003

The evolution of social behavior in the prehistoric American southwest.

Long House Valley, located in the Black Mesa area of northeastern Arizona (USA), was inhabited by the Kayenta Anasazi from circa 1800 B.C. to circa A.D. 1300. These people were prehistoric precursors of the modern Pueblo cultures of the Colorado Plateau. A rich paleoenvironmental record, based on alluvial geomorphology, palynology, and dendroclimatology, permits the accurate quantitative reconstruction of annual fluctuations in potential agricultural production (kg maize/hectare). The archaeological record of Anasazi farming groups from A.D. 200 to 1300 provides information on a millennium of sociocultural stasis, variability, change, and adaptation. We report on a multi-agent computational model of this society that closely reproduces the main features of its actual history, including population ebb and flow, changing spatial settlement patterns, and eventual rapid decline. The agents in the model are monoagriculturalists, who decide both where to situate their fields and where to locate their settlements.

Cultural Evolution↗
PubMed1987

Spontaneous in vitro neoplastic evolution: selection of specific karyotypes in Chinese hamster cells.

Recurrent cytogenetic changes occurred reproducibly in vitro during the spontaneous neoplastic evolution of cultured Chinese hamster cells. In particular, excess 3q material appeared shortly after immortalization in numerous independent trials. By contrast, when clones were isolated at the earliest possible time after immortalization, a wide spectrum of types of cytogenetic evolution followed, which also resulted in transformed and tumorigenic cells. Clones with stable distinct colonial morphologies were used to demonstrate growth rate interactions when subpopulations compete. We conclude that specific recurring karyotypes are associated with specific stem lines with transient growth advantage during the early stages of in vitro carcinogenesis. Stem lines with other karyotypic change or no detectable karyotypic change are almost equally capable of undergoing the entire spontaneous neoplastic process in vitro.

Animals↗
PubMed1995

Synthetic Lignin Mineralization by Ceriporiopsis subvermispora Is Inhibited by an Increase in the pH of the Cultures Resulting from Fungal Growth.

(sup14)C-synthetic lignin mineralization by the basidiomycete Ceriporiopsis subvermispora occurs at the highest rate (about 30% after 29 days) in liquid cultures containing 1% glucose and a growth-limiting amount (1 mM) of ammonium tartrate. The titers of manganese peroxidase (MnP) and laccase are lower in these cultures than in cultures containing 1% glucose and 10 mM ammonium tartrate, where the extent of lignin mineralization in the same period is only about 15%. The inverse correlation between enzyme activity and lignin mineralization is also observed when ammonium tartrate is replaced by ammonium chloride or Casamino Acids as the source of nitrogen. This phenomenon can be explained by a gradual increase in the pH of the medium that takes place only in the cultures with high nitrogen concentrations. Supporting this finding, when cultures with 1 mM ammonium tartrate were grown at different pHs, (sup14)CO(inf2) evolved more rapidly from those with pH values near the optimum for MnP activity. On the other hand, (sup14)CO(inf2) evolution from cultures containing 1% glucose supplemented with 1 mM ammonium tartrate plus 9 mM sodium tartrate was as low as that from cultures with a high ammonium tartrate concentration. Since the changes in the pH of these cultures were not as pronounced as those in cultures containing high nitrogen concentrations, tartrate itself may also be contributing to limit the extent of lignin mineralization. Considering that pH instability seems to constitute a common feature of fungal cultures, precautions must be taken to avoid underestimation of their ligninolytic efficiencies.

Journal Article↗
PubMed1977

The nonwhite as child: G. Stanley Hall on the education of nonwhite peoples.

Although he was a significant educational reformer during the progressive era, a founder of various journals in psychology and pedagogy, a profile writer, and the individual who brought Freud and Jung to the United States, G. Stanley Hall's ideas on the education of nonwhites were, for his period, quite conventional. Unlike those of some of his contemporaries, Hall's racial ideas were not overtly vicious. He argued that nonwhites were the children of the human race and that their education, like that of children of particular ages, should be based on an understanding of their indigenous culture and inherent capabilities. This argument, although reformist in tone, supported a policy of nonwhite subservience.

Black or African American↗
PubMed2003

Biocultural orchestration of developmental plasticity across levels: the interplay of biology and culture in shaping the mind and behavior across the life span.

The author reviews reemerging coconstructive conceptions of development and recent empirical findings of developmental plasticity at different levels spanning several fields of developmental and life sciences. A cross-level dynamic biocultural coconstructive framework is endorsed to understand cognitive and behavioral development across the life span. This framework integrates main conceptions of earlier views into a unifying frame, viewing the dynamics of life span development as occurring simultaneously within different time scales (i.e., moment-to-moment microgenesis, life span ontogeny, and human phylogeny) and encompassing multiple levels (i.e., neurobiological, cognitive, behavioral, and sociocultural). Viewed through this metatheoretical framework, new insights of potential interfaces for reciprocal cultural and experiential influences to be integrated with behavioral genetics and cognitive neuroscience research can be more easily prescribed.

Aging↗
PubMed1994

Cytomegalovirus colitis in HIV-1-infected patients: a prospective research in 55 patients.

OBJECTIVE: To determine criteria for the diagnosis of cytomegalovirus (CMV) colitis and to analyse stages of the course and prognosis of CMV colonic involvement in HIV-1-infected patients. DESIGN: Prospective search for CMV colonic involvement with systematic biopsies to search for CMV intranuclear inclusion bodies and for CMV culture. The evolution of CMV colonic involvement was estimated using further coloscopies and autopsy. SETTING: Infectious diseases department in a tertiary referral teaching hospital in Paris, France. PARTICIPANTS: Fifty-five consecutive patients with HIV-1 infection, who had not previously received anti-CMV drugs, and who had at least one coloscopy performed. RESULTS: According to initial coloscopy, colitis, either ulcerative or inflammatory, was found in nine (16%) out of the 55 patients, CMV intranuclear inclusions were present in the colon of four (7%) patients, and colonic cultures were positive for CMV in 15 (27%) patients. The results of the initial coloscopy showed a positive correlation between endoscopic colitis (either ulcerative or inflammatory), CMV inclusions and positive CMV culture from colonic biopsies. The absence of endoscopic ulcerative lesions had a 98% (49 out of 50) negative predictive value for recording CMV inclusions in the colon (95% confidence interval, 89-100). CMV inclusions were recorded in three out of five ulcerative colitis. Male homosexuality, HIV-1 infection stages IVB, C1, D or E, according to the Centers for Disease Control and Prevention classification, CD4 lymphocyte count < 200 x 10(6)/l and CMV viraemia also correlated positively with CMV colonic involvement. During the observation period (mean, 7.3 months), the estimated incidence of CMV colitis according to coloscopic studies was 13%. Deterioration in condition was the most frequent spontaneous evolution of CMV colonic infection, whereas anti-CMV treatment resulted in an improvement. Ulcerative lesions occurred earlier in patients with colonic CMV inclusions or positive colonic CMV culture than in patients without CMV colonic involvement at the initial coloscopy. CMV colitis occurred late in the course of HIV-1 infection, on average 4 months before death. The presence of CMV inclusions was an indicator of poor prognosis with earlier occurrence of CMV viraemia and retinitis and no survival after 9 months. CONCLUSIONS: These results confirm that the colon is a target organ for CMV in HIV-1-infected patients. Coloscopy should be used to diagnose CMV colitis, because of the close correlation between endoscopic and histological data (i.e., intranuclear inclusions). This combination allows us to propose an evolutive staging of CMV colonic involvement and provide stratification criteria to assess the efficacy of anti-CMV drugs.

AIDS-Related Opportunistic Infections↗
PubMed1997

Gene-culture coevolution and sex ratios: II. Sex-chromosomal distorters and cultural preferences for offspring sex.

Cultural preferences for the sex of offspring may produce behavior, such as female infanticide, sex-selective abortion and sex-selective parental investment, which alter the sex ratio in a population. Empirical evidence suggests that some genetic sex-ratio distorters are located on the sex chromosomes. Interactions between cultural preferences and sex-linked sex-ratio distorters are examined. Criteria for the spread of cultural preferences and sex-chromosomal distorter alleles are derived analytically, and the coevolution of preferences and distorters is examined through numerical iteration. Evolutionary equilibria and trajectories of gene-culture interactions involving sex-chromosomal distorter alleles may produce severely male- or female-biased primary sex ratios and adult sex ratios in populations. Adult sex ratios, primary sex ratios, allele frequencies and the prevalence of cultural preferences in the population are sensitive to initial conditions and cultural transmission parameters. During the coevolutionary process phenoallelic association is observed in many cases and is associated with unusual dynamics.

Adult↗
PubMed1992

Gene-culture coevolution: toward a general theory of vertical transmission.

A general formulation of cultural and genetic transmission is developed. The cultural transmission is vertical and the genetics may involve multiple loci. Each individual is represented by a phenogenotype, and conditions are given under which the evolutionary dynamics of phenogenotype frequencies are reducible to phenogametic or phenoallelic frequencies. The interaction between genes and culture is specified by an association measure, and results on the order of magnitude of this association at equilibrium are presented.

Biological Evolution↗
PubMed1999

Genomic views of human history.

New tools of genomic analysis shed light on historical puzzles. Migrations of ancient peoples, differences in migration patterns of males and females, historical demography of cultures with ancient roots, and patterns of human genetic diversity are increasingly the focus of integrated analysis by historians, anthropologists, and geneticists.

Anthropology↗
PubMed2001

Multigeneration zinc acclimation and tolerance in Daphnia magna: implications for water-quality guidelines and ecological risk assessment.

Development of zinc tolerance is described for the cladoceran Daphnia magna Straus. Zinc tolerance (i.e., toxicity and deficiency) was monitored during successive generations of D. magna acclimated to different zinc concentrations. Survival, reproduction, carapax length measurements, and cellular energy allocation assessments were used as test endpoints. Special attention was paid to the consequences of zinc deficiency. The zinc acclimation concentration clearly influenced the overall fitness of the organism. After several generations of acclimation, an optimal concentration curve was observed, with an optimum zinc concentration between 300 and 450 microg/L. Zinc deficiency resulted in a lower zinc tolerance, a higher coefficient of variation for brood size, and an increased pH sensitivity. These results clearly indicate that (background) zinc concentrations present in test and culture media have to be considered in the evaluation of toxicity test results, especially when the toxicity data are used for water-quality guideline derivation and/or ecological risk assessment. Culture and test media containing very little or no zinc do not provide a basis for useful ecotoxicological data.

Adaptation, Physiological↗
PubMed1995

The neurobiology of human consciousness: an evolutionary approach.

Human brains are basically primate in design, but in addition have representational mechanisms that give human consciousness a special character. The evolution in hominids of new kinds of representational skill--both nonverbal and verbal--produced our capacity for skilled rehearsal and explicit memory retrieval, and allowed the invention of conventional, or public representations, including languages and external symbols. The latter have created demands at the cultural level that greatly influence the deployment of cerebral resources. The spiralling interaction of brain and culture in evolution has resulted in a unique quasi-modular architecture at the highest levels of human cerebral integration.

Animals↗