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PubMed1993

The effects of written autobiographical recollection induction procedures on mood.

This study assessed the effects of group induction procedures that are practical in their administration (written format) and also individualized. Fifty-four females and 36 males were assigned randomly to one of three conditions. Conditions One and Two consisted of subjects being asked to think of the two saddest or two happiest events of their lives, respectively. Condition Three consisted of a control condition in which subjects were asked to read a geography article. The procedure produced marked decreases in depression (p < .001) and anxiety (p = .001) as mood states in Condition One (happy events) and marked increases in depression (p < .001) and anxiety (p < .001) in Condition Two (sad events). These procedures are particularly suitable for mood induction in a group setting.

Adolescent↗
PubMed2000

Heterogeneity of multiple sclerosis lesions: implications for the pathogenesis of demyelination.

Multiple sclerosis (MS) is a disease with profound heterogeneity in clinical course, neuroradiological appearance of the lesions, involvement of susceptibility gene loci, and response to therapy. These features are supported by experimental evidence, which demonstrates that fundamentally different processes, such as autoimmunity or virus infection, may induce MS-like inflammatory demyelinating plaques and suggest that MS may be a disease with heterogeneous pathogenetic mechanisms. From a large pathology sample of MS, collected in three international centers, we selected 51 biopsies and 32 autopsies that contained actively demyelinating lesions defined by stringent criteria. The pathology of the lesions was analyzed using a broad spectrum of immunological and neurobiological markers. Four fundamentally different patterns of demyelination were found, defined on the basis of myelin protein loss, the geography and extension of plaques, the patterns of oligodendrocyte destruction, and the immunopathological evidence of complement activation. Two patterns (I and II) showed close similarities to T-cell-mediated or T-cell plus antibody-mediated autoimmune encephalomyelitis, respectively. The other patterns (III and IV) were highly suggestive of a primary oligodendrocyte dystrophy, reminiscent of virus- or toxin-induced demyelination rather than autoimmunity. At a given time point of the disease--as reflected in autopsy cases--the patterns of demyelination were heterogeneous between patients, but were homogenous within multiple active lesions from the same patient. This pathogenetic heterogeneity of plaques from different MS patients may have fundamental implications for the diagnosis and therapy of this disease.

Adolescent↗
PubMed2006

Clinicopathological analysis of 598 malignant lymphomas in Taiwan: seven-year experience in a single institution.

The clinicopathological characteristics of malignant lymphomas vary according to geography. The purpose of this study is to determine the distribution and clinicopathological characteristics of malignant lymphomas in Taiwan. Archival tissue from 598 malignant lymphomas during the period of 1995-2002 was retrieved. They were reclassified according to the World Health Organization classification system. Clinical data, including age, gender, clinical staging, and follow-up, were scrutinized. There were 330 males and 268 females. The median age at onset of disease was 56 years for B-cell lymphoma (BCL), 50 years for T/NK-cell lymphoma (TCL), and 26 years for Hodgkin's lymphoma (HL). BCL accounted for 80.6%, TCL for 12.4%, and HL for 7%. The major subtypes of non-HL were diffuse large B-cell lymphoma, follicular lymphoma, plasma cell myeloma, marginal zone lymphoma of mucosa-associated lymphoid tissue type, mantle cell lymphoma, unspecified peripheral TCL, and nasal type T/NK-cell lymphoma. Nodular sclerosing subtype was the most common in HL. The frequencies of TCL and HL were relatively low. For histological subtype, enteropathy-type TCL and primary bone marrow HL had higher frequency and poorer prognosis. The 5-year overall survival of BCL, TCL, and HL was 58.9, 34.7, and 83.5%, respectively. To the best of our knowledge, this is the largest series study of malignant lymphoma in Taiwan. Immunophenotype, histological subtype, and clinical stage play significant roles in prognosis (P < 0.05).

Adult↗
PubMed2006

Predictors of South African male testosterone levels: the THUSA study.

The process of urbanization occurring in many developing countries may have consequences for reproductive endocrine function. Here, we test predictions concerning variation in South African male testosterone levels among subgroups across an urbanization gradient representing differences in both geography and socioeconomic status. Subjects included 364 males aged between 20 and 82 comprising a cross-sectional study conducted between 1996 and 1998. Testosterone levels were measured from serum samples obtained between 08:00 and 11:00. In ANCOVA analysis, male testosterone levels differed significantly along this rural-to-urban gradient, with members of the most urban group having higher testosterone levels than groups of farmers and inhabitants of informal housing areas adjacent to towns. Testosterone levels declined with age and were negatively related to body mass index (BMI). Testosterone levels did not differ according to HIV status. Further exploratory ANCOVA analyses revealed that physical activity levels, depression, affect, and hostility were not significantly associated with variation in testosterone levels. These data help document causes of variation in male testosterone levels in a context of urbanization and may have implications for clinical outcomes such as the development of a male hormonal contraceptive or prostate cancer.

Adult↗
PubMedDate not supplied

Ancient mitochondrial DNA from Malaysian hair samples: some indications of Southeast Asian population movements.

The late Pleistocene and early Holocene population history of Southeast Asia is not well-known. Our study provides new data on mitochondrial DNA (mtDNA) lineages of the aboriginal inhabitants of the Malay Peninsula, and through an extensive comparison to the known mtDNA diversity in Southeast and East Asia, provides some new insights into the origins and historical geography of certain mtDNA lineages in the region. We extracted DNA from hair samples (dating back 100 years) preserved in the Duckworth Collection and belonging to two Peninsular Malaysian individuals identified as "Negrito." Ancient DNA was analyzed by sequencing hypervariable region I (HVS-I) of the mtDNA control region and the mtDNA region V length polymorphism. The results show that the maternal lineages of these individuals belong to a recently defined haplogroup B sub-branch called B4c2. A comparison of mitochondrial haplotypes and haplogroups with those of 10,349 East Asian individuals indicates their very restricted geographical distribution (southwestern China, Southeast Asia Peninsula, and Indonesia). Recalculation of the B4c2 age across all of East Asia ( approximately 13,000 years) and in different subregions/populations suggests its rapid diffusion in Southeast Asia between the end of the Last Glacial Maximum and the Neolithic expansion of the Holocene.

Anthropology, Physical↗
PubMed2003

The names of Spain: a study of the isonymy structure of Spain.

In order to estimate the isonymy structure of Spain, we studied surname distribution in 283 Spanish towns based on 3.625 million telephone users selected from 6.328 million users, downloaded from a commercial CD-ROM which contains all 13 million users in the country. Since in Spain the surname is made by the paternal and the maternal surname, it was possible to classify surnames according to parental origin. Two matrices of isonymy distances, one for paternal and one for maternal surnames, were constructed and tested for correlation with geographic distance. For the whole of Spain, Euclidean distance was significantly but weakly correlated with geographic distance both for paternal and maternal surnames, with r = 0.205 +/- 0.013 and r = 0.263 +/- 0.012, respectively. Two dendrograms of the 283 sampled towns were built from the two matrices of Euclidean distance. They are largely colinear. Four main clusters identified by the dendrograms are correlated with geography. Given the surname structure of Spain, we were able to calculate from isonymy and for each town 1). total or expressed inbreeding, 2). random or expected inbreeding, and 3). local inbreeding. Total inbreeding, F(IT), was highest in the North Atlantic regions and lowest along the Mediterranean Coast. The lowest levels were found in Andalusia, Catalunyia, Valencia, and Navarra. Random inbreeding, F(ST), had a similar geographical pattern. Local inbreeding, F(IS), was relatively uniform in the whole of Spain. In towns, random inbreeding dominates over local inbreeding. From the analysis, it emerges that the northwestern area of Spain is the most inbred.

Female↗
PubMed2001

Genetic relationships between Amerindian populations of Argentina.

A total of 495 individuals from five different Argentinian tribes was examined for variation in 23 blood group and protein genetic systems, and the results were integrated with previous data on some of these systems. These tribes generally present RH * R1, PGM1 * 1, and ACP * A frequencies lower and RH * R2, ESD * 1, and GLO * 1 prevalences higher than those observed in other South American Indian groups. Earlier studies with mitochondrial DNA showed that haplogroup A was present in low frequencies in these tribes, but haplogroup B showed a high prevalence among the Mataco. Average heterozygosities are very similar in the five tribes, while estimates of non-Indian ancestry are generally low. Both the blood group and protein, as well as the mtDNA data sets, divide the five tribes into two groups, and the relationships obtained with the blood group and protein systems are exactly those expected on the basis of geography and language. However, the topology obtained with the mtDNA results was different, possibly due to sampling effects or diverse patterns of exchange between the groups related to sex.

Argentina↗
PubMed2001

Evolution of dentition in prehistoric Ohio Valley Native Americans III. Metrics of deciduous dentition.

Deciduous tooth size in Native Americans of the Ohio Valley area is fairly stable from the terminal Late Archaic (3200 BP) through the Late Prehistoric (350 BP) periods. Some fluctuation in average size did occur during this time. These fluctuations most likely reflect random changes due to gene drift. However, no difference in the pattern of interactions among the sizes of teeth (covariance structures) can be demonstrated during this period. Principal components analysis of the buccolingual and mesiodistal dimensions in the total sample indicate that the major axis of deciduous tooth size in the Ohio Valley population shows an allometric relationship, with the dimensions of the anterior teeth increasing (or decreasing) as the 1.33 power of the dimension of m1(1) and as the 2.0 power of the dimension of m2(2). Comparison of the Ohio Valley samples with other samples from the Eastern Woodlands suggests that geography may have played a minor role in structuring deciduous tooth size variation. For the most part, however, widely separated Eastern Woodlands populations appear to have been evolving independently with respect to deciduous tooth size.

Anthropology, Physical↗
PubMed1978

Genetic variation in transferrin alleles of rhesus macaques, Macaca mulatta.

The rhesus macaque displays an extensive polymorphism at the transferrin locus. A principal components analysis describes the variance and covariance of alleles at the transferrin locus in eight widely dispersed sample populations. Using an eigenvectorial representation of the covariance matrix and systematically approximated geographical locations the distribution of populations and transferrin alleles is compared. Alleles with high variance prove to be the determining factor in the placement of populations in a "genetic map" and provide a means for interpreting the low congruence of genetics and geography found.

Alleles↗
PubMed1985

Cranial variation in the terminal Late Archaic of Ohio.

Cranial and mandibular discrete traits and cranial metric traits were collected from 99-125 individuals in eight terminal Late Archaic sites. The analysis of ten metric traits in six samples showed that the samples shared the same generalized variance and that sexual dimorphism in the means of the metric traits was greater than inter-site differences. Since these samples share the same size and shape expression of a complex set of polygenic traits, we hypothesize a historical relationship among these samples. Discrete trait analysis showed a pattern of differentiation among the eight samples. This pattern of differentiation is related directly to the geographical separation between samples, and, as with metric traits, cultural differences do not contribute to the pattern of biological differences. The overall pattern of osteological variation in these samples can be summarized parsimoniously by paraphrasing the first law of geography: All of the terminal Late Archaic populations of Ohio were related to each other, but closer ones were more related than distant ones.

Cephalometry↗
PubMed1985

Principal-components analysis of Brazilian Indian anthropometric data.

Analysis of nine characteristics on 1,205 males and 932 females from 12 tribes or groups of tribes indicated a poor relationship between morphology and language, as well as moderate agreement with the variability expected considering geography only. Two samples in the Xingu area studied during an interval of half a century (1897-1947) showed remarkable similarity. The conformity of the Caingang morphology with those of other tribes and the distinctiveness of the Xavante and Tenetehara has been amply confirmed.

Anthropometry↗
PubMed1986

Anthropometry and the biological structure of the Hvar population.

Biological structure of the population of the island of Hvar was investigated by using the data on anthropometric variation among nine village populations; 24 body and 14 head dimensions were analysed from 487 male and 437 female adult subjects. Univariate and multivariate analyses revealed heterogeneity among the populations, which says much for the strength of the isolating factors on the island. Using correlations of anthropometric and geographic distance, the observed patterns of variation among villages were closely related to geography, suggesting migration to be an important factor in the formation of the island's population structure. Populations of the examined villages were further grouped to form the population of the eastern part and the population of the western part of the island, which have an ethnodemographic and sociocultural basis. The analyses revealed heterogeneity between the populations and thus provided evidence to support the hypothesis about the existence of the genetically different groups living in the same biotope.

Adult↗
PubMed1988

Genetic structure of the Saguenay, 1852-1911: evidence from migration and isonymy matrices.

The Saguenay is a region in northeastern Québec populated in the second half of the 19th century through migration from other parts of Québec. The present-day population of nearly 300,000 is the result of both immigration and high rates of intrinsic growth. This population has been of interest to geneticists because of the high incidence of certain hereditary diseases, notably spastic ataxia, tyrosinemia, agenesis of the corpus callosum, vitamin D-dependent rickets, and myotonic dystrophy. Parent-offspring migration and isonymy matrices were used to estimate random kinship using the Malécot model for six 10-year time periods from 1852-1911. Comparisons between two estimates of kinship--one from parent-offspring migration matrices (phi) and the other from isonymy (R)--and geographic distance were made using both product-moment and Mantel correlation. Comparisons of within- and between-subdivision kinship were made using nonparametric and Mantel correlation. Within-subdivision kinship from the phi matrix was also compared with kinship estimated from marriage dispensations for endogamous marriages. The estimates of random kinship from the parent-offspring matrices showed a good fit with geography. However, isonymy did not correlate well with geographic distance; and phi and R showed no correlation until the last two time periods, and the diagonal of phi did not correlate with the marriage dispensations. Examination of scatterplots of phi vs. R suggests that nonrandom migration during the process of settlement formation is responsible for the lack of correlation. While movement across space seems to be highly dependent on distance, nonrandom selection of migrants means that between-subdivision estimates of kinship based on migration are not congruent with those obtained by other methods. On the whole, genetic differentiation seems to have been low due to the high levels of movement between subdivisions and immigration. The weak dependence of genetic structure on geographic distances in the present population is demonstrated by mapping the geographic distribution of cases of three recessively inherited diseases.

Emigration and Immigration↗
PubMed1991

Does brain size variability provide evidence of multiple species in Homo habilis?

Endocranial volume (ECV) variability as measured by the coefficient of variation (CV) has been important in supporting the view that more than one species is represented in Homo habilis. Supporters of this view used a CV of 10 as a standard to determine that 1) the H. habilis CV of 12.7 indicates multiple species and 2) there is a low probability of H. habilis specimens KNM-ER 1470 and KNM-ER 1813 being members of the same taxon. This study examines published data for ECVs of fossil and extant hominoids to determine whether CV yields any information regarding species number in H. habilis. Results indicate that there is no empirical basis for using a CV of 10 as a standard to detect multiple species in H. habilis. Also, geography, time, sample choice, sex ratio, and measurement technique are complicating factors that must be considered when interpreting CVs for fossil samples. Additionally, the broad 95% statistical confidence limits (5.1-20.3) indicate that the CV estimate of 12.7 for H. habilis is not sufficiently reliable to allow biologically meaningful interpretation. However, if the CV for H. habilis is actually 12.7, it still falls within the range of variation for single species of modern hominoids. The evidence from ECV variability does not support the argument for multiple species in H. habilis.

Analysis of Variance↗
PubMed1993

Genetic relationships of European populations reflect their ethnohistorical affinities.

From 420 records of ethnic locations and movements since 2000 B.C., we computed vectors describing the proportions which peoples of the various European language families contributed to the gene pools within 85 land-based 5 x 5-degree quadrats in Europe. Using these language family vectors, we computed ethnohistorical affinities as arc distances between all pairs of the 85 quadrats. These affinities are significantly correlated with genetic distances based on 26 genetic systems, even when geographic distances, a common causative factor, are held constant. Thus, the ethnohistorical distances explain a significant amount of the genetic variation observed in modern populations. Randomizations of the records by chronology result in loss of significance for the observed partial correlation between genetics and ethnohistory, when geography is held constant. However, a randomization of records by location only results in reduced significance. Thus, while the historical sequence of the movements does not seem to matter in Europe, their geographic locations do. We discuss the implications of these findings.

Alleles↗
PubMed1994

Terrestrial adaptations in the postcranial skeletons of guenons.

Arboreal and semiterrestrial guenons show similar osteological features of the limbs across a wide range of species, environments, and geography, while the more terrestrially committed guenons exhibit greater morphological divergence. An ecomorphological comparison of two sympatric guenons living in Kibale Forest, Uganda, reveals an array of anatomical adaptations for terrestriality in the limbs of Cercopithecus lhoesti similar to those found in Erythrocebus patas. In contrast, Cercopithecus aethiops, although also frequent users of the terrestrial environment, generally exhibit fewer morphological adaptations characteristic of a terrestrial lifestyle. It appears that significant morphological modification for terrestriality has occurred twice within the diverse radiation of living guenons with C. aethiops perhaps representing a third group in the making.

Adaptation, Biological↗
PubMed1995

Anthropometric variation and the population history of Ireland.

Genetic variation among human populations can reflect a combination of contemporary patterns of gene flow and genetic drift as well as long-term population relationships due to population history. We examine the likely impact of past history and contemporary structure on the patterns of anthropometric variation among 31 counties in Ireland (made up of the two nations of the Republic of Ireland and Northern Ireland). Data for 17 anthropometric measures and parent-offspring migration on 7,214 adult Irish males were taken from the large data set originally collected by Dupertuis and Dawson in the mid-1930s (Hooton et al., 1955). Patterns of genetic similarity among 31 counties were assessed using R matrix methods that allow estimation of minimum genetic distances. These distances were compared to distances reflecting history, geography, and migration using matrix permutation methods. The results indicate that among-group variation in Ireland reflects past population history to a much greater extent than contemporary patterns of migration and population size. The midland counties are distinct from other populations, and their history suggests greater genetic input from early Viking invasions. A second major pattern in biological variation is a longitudinal gradient separating western and eastern counties. This gradient appears related to patterns of early settlement and/or a concentration in the east of later immigrants, particularly from England. Comparison of regional means with published data for several other European nations confirms these hypotheses.

Adult↗
PubMed2006

Cranial ontogeny of Papio baboons (Papio hamadryas).

Cranial form in subspecies of Papio baboons (Papio hamadryas) varies in relation to size, geography, and sex. However, knowledge about this variation is based mainly on adults, precluding direct assessments of the evolutionary factors that are ultimately responsible for adult shape variation. Consequently, this study tests hypotheses about the development of size and shape differences among subspecies of Papio baboons, anticipating limited evolutionary divergences in the ontogenetic pathways leading to adult endpoints. Geometric morphometric and bivariate allometric analyses are used to explore developmental size and shape variation. Allometric scaling in adult Papio baboons occurs because both sexes and all subspecies follow similar developmental pathways to a variety of adult forms. However, complex allometry contributes to form differences, producing potentially important shape differences that emerge during development. Modest shape differences that are statistically independent of size distinguish chacma baboons (P. h. ursinus) from other forms. A small-headed subspecies, the Kinda baboon (P. h. kindae), also presents a distinctive ontogeny, and may provide insights into the evolution of size change in this species. Variation among subspecies that is statistically independent of size involves the rostrum, zygomatic breadths, and cranial flexion. These features may be related to diet, but the precise biomechanical correlates of baboon form variation remain unclear.

Animals↗