African Origin (african + origin)

Distribution by Scientific Domains


Selected Abstracts


Evolutionary ecology, sexual conflict, and behavioral differentiation among baboon populations

EVOLUTIONARY ANTHROPOLOGY, Issue 5 2003
Peter Henzi
Abstract A central assumption of baboon socio-ecological models is that all populations have the same capacity to react to different environments. The burden of our argument is that this assumption needs to be reconsidered. Data suggest not only that hamadryas, but chacma as well, differ in interesting ways from the stock baboon model that has been derived, in the main, from earlier work on anubis and cynocephalus. Although environmental factors are behind these differences, much of their influence is a consequence of their effect on restricted ancestral populations, where selection for appropriate responses to the social challenges set by local conditions now constrains the nature of individual responses to contemporary environments. Available genetic evidence suggess a southern African origin for Papio at a time when climatic conditions were certainly no better than they are now and when temperatures, if nothing else, were probably lower. In light of this, a reconstruction of how climate has structured the sexual conflict between males and female charcma, which itself hinges on infanticide, can help explain not only the East African pattern, but also how the apparently anomalous hamadryas pattern has been derived. [source]


Hepatitis B or hepatitis C coinfection in HIV-infected pregnant women in Europe

HIV MEDICINE, Issue 7 2008
M Landes
Objectives The aim of the study was to investigate the prevalence of and risk factors for hepatitis C or B virus (HCV or HBV) coinfection among HIV-infected pregnant women, and to investigate their immunological and virological characteristics and antiretroviral therapy use. Methods Information on HBV surface antigen (HBsAg) positivity and HCV antibody (anti-HCV) was collected retrospectively from the antenatal records of HIV-infected women enrolled in the European Collaborative Study and linked to prospectively collected data. Results Of 1050 women, 4.9% [95% confidence interval (CI) 3.6,6.3] were HBsAg positive and 12.3% (95% CI 10.4,14.4) had anti-HCV antibody. Women with an injecting drug use(r) (IDU) history had the highest HCV-seropositivity prevalence (28%; 95% CI 22.8,35.7). Risk factors for HCV seropositivity included IDU history [adjusted odds ratio (AOR) 2.92; 95% CI 1.86,4.58], age (for ,35 years vs. <25 years, AOR 3.45; 95% CI 1.66,7.20) and HBsAg carriage (AOR 5.80; 95% CI 2.78,12.1). HBsAg positivity was associated with African origin (AOR 2.74; 95% CI 1.20,6.26) and HCV seropositivity (AOR 6.44; 95% CI 3.08,13.5). Highly active antiretroviral therapy (HAART) use was less likely in HIV/HCV-seropositive than in HIV-monoinfected women (AOR 0.34; 95% CI 0.20,0.58). HCV seropositivity was associated with a higher adjusted HIV RNA level (+0.28log10 HIV-1 RNA copies/mL vs. HIV-monoinfected women; P=0.03). HIV/HCV-seropositive women were twice as likely to have detectable HIV in the third trimester/delivery as HIV-monoinfected women (AOR 1.95; P=0.049). Conclusions Although HCV serostatus impacted on HAART use, the association between HCV seropositivity and uncontrolled HIV viraemia in late pregnancy was independent of HAART. [source]


Plumage-based phylogenetic analyses of the Merops bee-eaters

IBIS, Issue 3 2004
D. BRENT BURT
I review previous systematic work on the family Meropidae and present phylogenetic hypotheses derived from my analyses of colour, pattern and shape variation in 30 plumage regions among species and subspecies in this family. Consistent patterns are seen across shallow portions of the trees. Uncertainty remains concerning the placement of several deep branches within this group's phylogeny. In particular, the phylogenetic placement of Meropogon forsteni and Merops breweri, M. ornatus, M. hirundineus and M. boehmi remains uncertain. The biogeographical patterns in the resultant trees are similar with either a Southeast Asian or African origin for the family, with most of the early diversification occurring in Africa, and with multiple independent subsequent invasions of non-African areas. [source]


Hereditary amyloid neuropathy by transthyretin Val107 mutation in a patient of African origin

JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 3 2008
Julien Cassereau
[source]


The retail market for fresh cassava root tubers in the European Union (EU): the case of Copenhagen, Denmark , a chemical food safety issue?

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 2 2010
Lotte Kolind-Hansen
Abstract BACKGROUND: A number of retail shops in Copenhagen sell fresh cassava roots. Cassava roots contain the toxic cyanogenic glucoside linamarin. A survey was made of the shop characteristics, origin of the roots, buyers, shop owner's knowledge of toxicity levels, and actual toxicity levels. RESULTS: Shops selling fresh cassava were shown mostly to be owned by persons originating in the Middle East or Afghanistan, buyers were found to predominantly be of African origin, and sellers' knowledge concerning the potential toxicity was found to be very restricted. Seventy-six per cent of the roots purchased had a total cyanogenic potentials (CNp) above the 50 mg HCN equivalents kg,1 dry weight (d.w.) proposed as acceptable by an EU working group. Two of 25 roots purchased had CNp higher than 340 mg HCN eq. kg,1 d.w. CONCLUSION: The EU has previously made risk assessments concerning cassava and cyanogenic compounds. In the light of the conclusions drawn, the EU needs to make decisions about how to deal with the regulation and control of fresh cassava roots imported to the European food market. Also cassava root products and cassava leaves should be considered. Copyright © 2009 Society of Chemical Industry [source]


Geographical patterns of mitochondrial DNA variation in Apis mellifera iberiensis (Hymenoptera: Apidae)

JOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 1 2008
F. Cánovas
Abstract An extensive survey of mitochondrial haplotypes in honeybee colonies from the Iberian Peninsula has corroborated previous hypotheses about the existence of a joint clinal variation of African (A) and west European (M) evolutionary lineages. It has been found that the Iberian Peninsula is the European region with the highest haplotype diversity (12 haplotypes detected of the M lineage and 10 of the A lineage). The frequency of A haplotypes decreases in a SW-NE trend, while that of M haplotypes increases. These results are discussed in relation to hypotheses about the African origin of Apis mellifera and an early colonization of west Europe during intermediate Pleistocene glaciation events, followed by a regional differentiation. The extant pattern of haplotype frequency and distribution seems to be influenced at a regional scale by adaptation to local climatic conditions and the mobile beekeeping that has become a large-scale practice during the last decades. Other previous anthropogenic influences (Greek, Roman and Arab colonizations) are thought to be of minor importance in present day populations. Resumen Un extenso estudio de los haplotipos mitocondriales en colonias de la abeja doméstica de la Péninsula Ibérica ha corroborado las hipótesis previas acerca de la existencia de una variación clinal conjunta de los linajes evolutivos africano (A) y europeo occidental (M). Se ha encontrado que la Peninsula Ibérica es la región europea con la mayor diversidad (12 haplotipos detectados pertenecientes al linaje M y 10 al linaje A). La frecuencia de los haplotipos africanos disminuye en la orientación SW-NE, al tiempo que aumenta proporcionalmente la de los M. Estos resultados se analizan en relación a las hipótesis recientes que ubican el origen de Apis mellifera en África, junto con otras que postulan una colonización temprana de esta especie en Europa occidental, seguida de una diferenciación durante el Pleistoceno. El patrón geográfico actual de haplotipos y frecuencias a escala regional, parece estar influido por la adaptación a las condiciones climáticas locales y la trashumancia, práctica que ha adquirido grandes proporciones en las últimas décadas. Otras influencias antrópicas acontecidas como las colonizaciones de griegos, romanos y árabes han tenido posiblemente poca influencia sobre las poblaciones ibéricas actuales. [source]


Maximum likelihood estimates of admixture in northeastern Mexico using 13 short tandem repeat loci

AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 4 2002
Ricardo M. Cerda-Flores
Tetrameric short tandem repeat (STR) polymorphisms are widely used in population genetics, molecular evolution, gene mapping and linkage analysis, paternity tests, forensic analysis, and medical applications. This article provides allelic distributions of the STR loci D3S1358, vWA, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317, D7S820, CSF1PO, TPOX, TH01, and D16S539 in 143 Mestizos from Northeastern Mexico, estimates of contributions of genes of European (Spanish), American Indian and African origin in the gene pool of this admixed Mestizo population (using 10 of these loci); and a comparison of the genetic admixture of this population with the previously reported two polymorphic molecular markers, D1S80 and HLA-DQA1 (n = 103). Genotype distributions were in agreement with Hardy-Weinberg expectations (HWE) for almost all 13 STR markers. Maximum likelihood estimates of admixture components yield a trihybrid model with Spanish, Amerindian, and African ancestry with the admixture proportions: 54.99% ± 3.44, 39.99% ± 2.57, and 5.02% ± 2.82, respectively. These estimates were not significantly different from those obtained using D1S80 and HLA-DQA1 loci (59.99% ± 5.94, 36.99% ± 5.04, and 3.02% ± 2.76). In conclusion, Mestizos of Northeastern Mexico showed a similar ancestral contribution independent of the markers used for evolutionary purposes. Further validation of this database supports the use of the 13 STR loci along with D1S80 and HLA-DQA1 as a battery of efficient DNA forensic markers in Northeastern Mestizo populations of Mexico. Am. J. Hum. Biol. 14:429,439, 2002. © 2002 Wiley-Liss, Inc. [source]


Human Herpesvirus-8 (HHV-8)-Associated Primary Effusion Lymphoma in two Renal Transplant Recipients Receiving Rapamycin

AMERICAN JOURNAL OF TRANSPLANTATION, Issue 3 2008
E. Boulanger
The Akt/mammalian target of rapamycin (mTOR) signaling cascade has been demonstrated to be constitutively activated in several malignancies, including Kaposi sarcoma (KS) and human herpesvirus-8 (HHV-8)-associated primary effusion lymphoma (PEL). In organ transplant recipients, therapeutic change from cyclosporin to the mTOR inhibitor rapamycin can lead to regression of KS lesions. Recent experiments using PEL cell lines and murine xenograft PEL models suggested that rapamycin could inhibit the growth of PEL cells. In the present report, we describe the cases of two HIV-1-negative males of African origin who underwent renal transplantation and developed PEL while receiving rapamycin as immunosuppressive treatment. Both patients were retrospectively found to be HHV-8 seropositive before renal transplantation. The present case report suggests that rapamycin may not protect HHV-8-infected renal transplant recipients from occurrence of PEL or progression of pre-existing PEL. [source]


ON THE WHITE AND COLOURED MARBLES OF THE ROMAN TOWN OF CUICUL (DJEMILA, ALGERIA)

ARCHAEOMETRY, Issue 4 2010
F. ANTONELLI
This paper reports the results of an archaeometric study of the local and imported marbles found in the Roman town of Cuicul (now Djemila, Algeria), a research project funded by the Sixth Framework Programme of the European Union. Of the few imported coloured lithotypes that have been found, four are of Greek origin and one was imported from Asia Minor. In addition, two other classical Roman coloured stones found on the site are probably of local North African origin (most likely one from Numidia and one from Algeria). With regard to the grey and white marbles employed in the statuary and architecture, petrographic study in thin section and the ,13C and ,18O isotopic data emphasize the frequent use of the local fine-grained lithotype from Filfila (Skikda) together with imported Greek lithotypes (i.e., Pentelic marble, the dolomitic variety of Thasian marble, and Parian marble from Lakkoi) as well as different varieties of the so-called ,greco scritto', whose provenance in some cases still remains uncertain. In fact, the petrographic and geochemical features of the marbles do not always match those known for the classical ,greco scritto' from the quarry of Cap de Garde, near Annaba (Algeria). [source]