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PubMed1980

Evolution of cultured leukemic cell lines monitored by chromosomal and immunologic analysis.

We have investigated the karyotypes and markers of B lymphocyte differentiation in two leukemic cell lines, NALM-6-B and NALM-6-MI, both derived from a patient with non-T, non-B acute lymphoblastic leukemia. Both possess characteristics of thymus-independent, bursal-equivalent (B) lymphocytes. By means of immuno-fluorescence techniques, NALM-6-B was shown to possess 47% surface membrane immunoglobulin-positive (Slg+) cells, while NALM-6-MI is surface membrane immunoglobulin-negative (Slg-), but does possess cytoplasmic immunoglobulin M (ClgM+) in more than 90% of the cells. The Slg- ClgM+ phenotype, coupled with morphologic features, is consistent with NALM-6-MI being arrested at a stage early in B-lymphocyte differentiation (a "pre-B" cell). The predominant banded chromosome karyotype of NALM-6-B is pseudodiploid with a translocation of chromosomal material from the long arm of a chromosome 5 to the short arm of a chromosome 12 (5q-/12p+) and a marker Y chromosome. NALM-6-MI possesses the same marker Y chromosome and a deletion of the long arm of chromosome 5(5q-) since in most cells material missing from chromosome 5 does not appear on the short arm of chromosome 12. Within the limits of resolution available with the banding technique, no other karyotypic differences are observed in the two cell lines. The history of the two cell lines, the karyotypic analysis, and the pattern of immunoglobulin markers indicate the possible clonal evolution of NALM-6-MI from NALM-6-B and implicate a portion of the long arm of chromosome 5 in lymphoid differentiation of these leukemic cell lines.

Adult↗
PubMed1985

Gene-culture coevolution: models for the evolution of altruism with cultural transmission.

Models of sexual haploids under kin selection are constructed. The trait of altruism is transmitted vertically from parent to child, but not in a strictly genetic manner. Two systems of altruism are considered: parent-to-offspring and sib-to-sib. In the former case it is shown that even when Hamilton's conditions for the success of genetically determined altruism are met, genes that increase the transmission of altruism may not invade the population. With sib-to-sib altruism, such genes will always increase initially.

Alleles↗
PubMedDate not supplied

Establishment, characterization, and evolution of cultures enriched in type-2 astrocytes.

The aim of the present study was to prepare cultures enriched in type-2 astrocytes (AS) and to analyze some of the properties of these cells over relatively long culture periods. Cultures enriched in type-2 AS were obtained by subculturing, at low cell density and in the presence of fetal calf serum, a cell population containing numerous bipotential glial precursors. This cell population was detached mechanically from 2- to 3-week primary mixed glial cultures prepared from 1-day postnatal rat cerebral cortex. The cellular composition of the subcultures was analyzed immunocytochemically over a period of 3 weeks using various combinations of antibodies, recognizing a set of differentiated and a set of undifferentiated glial antigens (glial fibrillary acidic protein [GFAP], galactocerebroside, sulfatide, gangliosides binding the monoclonal antibodies A2B5 and LB1, fibronectin). Most LB1+, A2B5+ glial precursors differentiated into type-2 AS within a week. At this stage, type-2 AS accounted for more than 70% of cells in the cultures and exhibited the characteristic features previously described for these cells (stellate shape, GFAP, LB1 and A2B5 positivity, ability to accumulate [3H]GABA and to synthesize chondroitin sulfate, low proliferative activity). About one third of the type-2 AS also were recognized by O4 (antisulfatide) antibodies. The major contaminants were macrophages (10-15%) and fibroblastic cells (5-10%). In longer term cultures, type-2 AS tended to lose several of these features. Many acquired a flat, polygonal shape and lost LB1 positivity. The ability to accumulate [3H]GABA progressively decreased, as did the expression of chondroitin sulfate, although to a lesser degree. Although losing several of their properties, type-2 AS did not appear to acquire the properties of type-1 AS: their proliferative activity remained very low, and they did not express class II antigens of the major histocompatibility complex upon stimulation with gamma-interferon. Some became positive for fibronectin.

Animals↗
PubMed1986

Heat evolution of cultured human keratinocytes.

The heat production of normal and transformed human epidermal keratinocytes precultured in Petriperm tissue culture dishes was measured calorimetrically. For this purpose, the membrane at the bottom of the culture dish was cut out aseptically and put into a microcalorimeter vessel with the cell layer inwards. A continuous heat output of (83 +/- 12) pW/cell was measured for normal keratinocytes from a confluent primary culture. A value of (134 +/- 35) pW/cell was obtained when the transformed keratinocyte line SV-K14 was used. The method described in this paper is simple, leads to reproducible results, and can be easily adapted to the calorimetric study of other mammalian cells in vitro.

Calorimetry↗
PubMed1989

A hierarchical model of the evolution of cooperation in cultural systems.

In this paper the following problem is addressed: "Under what conditions can a collection of individual organisms learn to cooperate when cooperation appears to outwardly degrade individual performance at the outset. In order to attempt a theoretical solution to this problem, data from a real world problem in anthropology is used. A distributed simulation model of this system was developed to assess its long term behavior using using an approach suggested by Zeigler (Zeigler, B.P., 1984, Multifaceted Modelling and Discrete Event Simulation (Academic Press, London)). The results of the simulation are used to show that although cooperation degrades the performance potential of each individual, it enhances the persistence of the individual's partial solution to the problem in certain situations."

Animals↗
PubMed1992

The evolution of culture and cohesion in the group treatment of ego impaired children.

The challenge of group treatment with ego impaired children is to provide a situation in which their maladaptive efforts to organize volatile affects and impulses can be tolerated and structured. This article addresses the process of culture building in group and how it can provide a cohesive structure for affective expression that is acceptable and tolerable to the defensive, resistant child. In particular, the author will argue that it is through the sense of normality and commonality engendered by indigenous peer culture that the members initially develop a structure and language for affiliation, play, and mutual identification. By facilitating the cohesion of indigenous peer culture, the therapist creates a sufficient holding environment to begin a dialogue involving both verbal and nonverbal communication. For children who are difficult to engage in discussion, let alone treatment, this dialogue is the essential process for creating a corrective emotional experience. Through a concise case study, the author describes the process by which the children's efforts to express and create their own culture are cultivated, managed, and understood.

Child↗
PubMed1975

Models for cultural inheritance: a general linear model.

A theory of cultural evolution is proposed based on a general linear mode of cultural transmission. The trait of an individual is assumed to depend on the values of the same trait in other individuals of the same, the previous or earlier generation. The transmission matrix W has as its elements the proportional contributions of each individual (i) of one generation to each individual (j) of another. In addition, there is random variation (copy error or innovation) for each individual. Means and variances of a group of N individuals change with time and will stabilize asymptotically if the matrix W is irreducible and aperiodic. The rate of convergence is geometric and is governed by the largest non-unit eigenvalue of W. Groups fragment and evolve independently if W is reducible. The means of independent groups vary at random at a predicted rate, a phenomenon termed "random cultural drift". Variances within a group tend to be small, assuming cultural homogeneity. Transmission matrices of the teacher/leader type, and of parental type have been specifically considered, as well as social hierarchies. Various limitations, extensions, and some chances of application are discussed.

Cultural Evolution↗
PubMed2005

The descent of words: evolutionary thinking 1780-1880.

Histories of evolutionary thought are dominated by organic evolution. The colossus in our midst that is evolutionary biology casts its shadow over history, making it appear that what is so widespread and important today was always the primary subject of evolutionary speculation. Thus many histories assume that the core meaning of evolution is the change of organic life and that other forms of evolutionary thinking, such as linguistic, social or cultural evolution, are only analogies or offshoots of the main biological evolutionary trunk. Ironically this is an ahistorical understanding. Long before the work of Charles Darwin, scholars were independently developing evolutionary concepts such as descent with modification and divergence from a common stock in order to understand cultural change.

Biological Evolution↗
PubMed2003

Spread of cattle led to the loss of matrilineal descent in Africa: a coevolutionary analysis.

Matrilineal descent is rare in human societies that keep large livestock. However, this negative correlation does not provide reliable evidence that livestock and descent rules are functionally related, because human cultures are not statistically independent owing to their historical relationships (Galton's problem). We tested the hypothesis that when matrilineal cultures acquire cattle they become patrilineal using a sample of 68 Bantu- and Bantoid-speaking populations from sub-Saharan Africa. We used a phylogenetic comparative method to control for Galton's problem, and a maximum-parsimony Bantu language tree as a model of population history. We tested for coevolution between cattle and descent. We also tested the direction of cultural evolution--were cattle acquired before matriliny was lost? The results support the hypothesis that acquiring cattle led formerly matrilineal Bantu-speaking cultures to change to patrilineal or mixed descent. We discuss possible reasons for matriliny's association with horticulture and its rarity in pastoralist societies. We outline the daughter-biased parental investment hypothesis for matriliny, which is supported by data on sex, wealth and reproductive success from two African societies, the matrilineal Chewa in Malawi and the patrilineal Gabbra in Kenya.

Africa South of the Sahara↗
PubMed1966

Antibody production by cells in tissue culture. I. Morphological evolution of lymph node and spleen cells in culture.

An organ culture technique was used to investigate the migration and the morphological evolution of lymphocytes from lymphopoietic tissues. This evolution was compared with the behavior of cells extracted from the tissue and kept in nutritive medium in vitro. It was found that cells were continuously migrating from the fragments of lymph nodes or spleen, and were attaching to the glass. They spread on glass, their protoplasm enlarged and their nucleus became clearer. The evolution towards blastoid cells was identical with that described under artificial stimulation by PHA for example. Cytological identification of the cells actively engaged in antibody synthesis (as detected by local hemolysis in gum) at the time of staining, showed that several distinct cellular types were active, including plasma cells and macrophagelike cells. It is assumed that the stimulated lymphocytes, after spontaneous migration from the tissue are able to evolve into an "immunoblast" stage and then, eventually after fixation upon a physical support, to initiate antibody synthesis.

Antibody Formation↗
PubMed2004

The Clinical Hand: A curricular map for relationship-centered care.

Learning and teaching the complex craft of relationship-centered care in the context of the competing demands of clinical family medicine can be challenging. The "Clinical Hand" is an educational aid, which serves as a curricular map specifying what content and skills are important for relationship centered care. The Clinical Hand illuminates seven features of the clinical encounter. "Opening the Hand" symbolizes the importance of relationship and healing intention. The "Grip of Power" highlights the significance of locating, owning, aiming, and sharing power in the relationship. The "Wrist Lines of Guidance" name three goals for every visit and three types of clinical encounters. The "Fingers of Direction" identify five sequential tasks for each encounter, and the "Nails for Trouble" remind residents of the BATHE technique. The "Palm of Hope" represents a diagnostic and management tool, and a "Swinging Cultural Ape" emphasizes the importance of evolution, culture, and the need to "keep swinging." The use of the Clinical Hand in a residency program is briefly discussed.

Curriculum↗
PubMed1994

The paradox of HIV/AIDS as expanding consciousness.

A heuristic approach employing Newman's method for pattern identification was used to examine the theory of health as expanding consciousness in persons with human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS). Themes derived from the interview of nine gay men portrayed a pattern of alienation during childhood, followed by a breaking away from family, and progressing to cycles of aloneness and searching. Recognition of HIV/AIDS in their lives brought them to a turning point of more meaningful connectedness. This pattern is viewed as expanding consciousness and possibly a phenomenon of cultural evolution.

Acquired Immunodeficiency Syndrome↗