Complete sequence of a new HLA-B35 allele found in a tribe of Mapuche Indians in the south of Argentina

The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide sequence database and have been assigned the accession number U17107. The nameB*3509 was officially assigned by the WHO Nomenclature Committee in December 1994     

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.     

Allele and genotype frequencies of metabolic genes in Native Americans from Argentina and Paraguay

Interethnic differences in the allele frequencies of CYP2D6, NAT2, GSTM1 and GSTT1 deletions have been documented for Caucasians, Asians, and Africans population. On the other hand, data on Amerindians are scanty and limited to a few populations from southern areas of South America. In this report we analyze the frequencies of 11 allele variants of CYP2D6 and 4 allele variants of NAT2 genes, and the frequency of GSTM1 and GSTT1 homozygous deleted genotypes in a sample of 90 donors representing 8 Native American populations from Argentina and Paraguay, identified as Amerindians on the basis of their geographic location, genealogical data, mitochondrial- and Y-chromosome DNA markers. For CYP2D6, 88.6% of the total allele frequency corresponded to *1, *2, *4 and *10 variants. Average frequencies for NAT2 *4, *5, *6 and *7 alleles were 51.2%, 25%, 6.1%, and 20.1%, respectively. GSTM1 deletion ranged from 20% to 66%, while GSTT1 deletion was present in four populations in less than 50%. We assume that CYP2D6 *2, *4, *10, *14; NAT2 *5, *7 alleles and GSTM1 and GSTT1 *0/*0 genotypes are founder variants brought to America by the first Asian settlers.     

African ancestry of the population of Buenos Aires

The population of Argentina today does not have a “visible” black African component. However, censuses conducted during most of the 19th century registered up to 30% of individuals of African origin living in Buenos Aires city. What has happened to this African influence? Have all individuals of African origin died, as lay people believe? Or is it possible that admixture with the European immigrants made the African influence “invisible?” We investigated the African contribution to the genetic pool of the population of Buenos Aires, Argentina, typing 12 unlinked autosomal DNA markers in a sample of 90 individuals. The results of this analysis suggest that 2.2% (SEM = 0.9%) of the genetic ancestry of the Buenos Aires population is derived from Africa. Our analysis of individual admixture shows that those alleles that have a high frequency in populations of African origin tend to concentrate among 8 individuals in our sample. Therefore, although the admixture estimate is relatively low, the actual proportion of individuals with at least some African influence is approximately 10%. The evidence we are presenting of African ancestry is consistent with the known historical events that led to the drastic reduction of the Afro‐Argentine population during the second half of the 19th century. However, as our results suggest, this reduction did not mean a total disappearance of African genes from the genetic pool of the Buenos Aires population. Am J Phys Anthropol 128:164‐170, 2005. © 2005 Wiley‐Liss, Inc.     

Histopathological effects of cisplatin,doxorubicin and 5-flurouracil (5-FU) on the liver of male albino rats

Cisplatin, doxorubicin and fluorouracil (5-FU), drugs belonging to different chemical classes, have been extensively used for chemotherapy of various cancers. Despite extensive investigations into their hepatotoxicity, there is very limited information on their effects on the structure and ultra-structure of liver cells in vivo. Here, we demonstrate for the first time, the effects of these three anticancer drugs on rat liver toxicity using both light and electron microscopy. Light microscopic observations revealed that higher doses of cisplatin and doxorubicin caused massive hepatotoxicity compared to 5-FU treatment, including dissolution of hepatic cords, focal inflammation and necrotic tissues. Interestingly, low doses also exhibited abnormal changes, including periportal fibrosis, degeneration of hepatic cords and increased apoptosis. These changes were confirmed at ultrastructural level, including vesiculated rough endoplasmic reticulum and atrophied mitochondria with ill-differentiated cisternae, dense collection of macrophages and lymphocytes as well as fibrocytes with collagenous fibrils manifesting early sign of fibrosis, especially in response to cisplatin and doxorubicin -treatment. Our results provide in vivo evidence, at ultrastructural level, of direct hepatotoxicity caused by cisplatin, doxorubicin and 5-FU at both light and electron microscopi. These results can guide the design of appropriate treatment regimen to reduce the hepatotoxic effects of these anticancer drugs.     

The Ras guanine nucleotide exchange factor RasGRF1 promotes matrix metalloproteinase-3 production in rheumatoid arthritis synovial tissue

Introduction  

Fibroblast-like synoviocytes (FLS) from rheumatoid arthritis (RA) patients share many similarities with transformed cancer cells, including spontaneous production of matrix metalloproteinases (MMPs). Altered or chronic activation of proto-oncogenic Ras family GTPases is thought to contribute to inflammation and joint destruction in RA, and abrogation of Ras family signaling is therapeutic in animal models of RA. Recently, expression and post-translational modification of Ras guanine nucleotide releasing factor 1 (RasGRF1) was found to contribute to spontaneous MMP production in melanoma cancer cells. Here, we examine the potential relationship between RasGRF1 expression and MMP production in RA, reactive arthritis, and inflammatory osteoarthritis synovial tissue and FLS.     

Natural occurrence of deoxynivalenol, 3-acetyl-deoxynivalenol, 15-acetyl-deoxynivalenol,nivalenol, 4,7-dideoxynivalenol,and zearalenone in polish wheat

Three wheat samples collected in 1987 in Central Poland and naturally infected withFusarium spp were analyzed for the presence ofFusarium spp andFusarium toxins. Heads were separated into three fractions: kernels with visibleFusarium damage, healthy looking kernels, and chaff + rachis. The samples contained deoxynivalenol (2.0 – 40.0μg/g), nivalenol (O.O1μg/g), 4,7-dideoxynivalenol (0.10 – 0.15μg/g). 15-acetyldeoxynivalenol (0.10–2.00 μg/g), 3-acetyldeoxynivalenol (O/1Oμg/g), and zearalenone (0.01–2.00μg/g). This is the first report about 15 - acetyldeoxynivalenol in European wheat and the co-occurrence of 3 - acetyldeoxynivalenol and 15-acetyldeoxynivalenol in the same sample of contaminated cereals.     

Demography and blood genetics of Argentinian Mapuche Indians

The whole Mapuche Indian community of Blancura Centro was covered by a demographic census, with special attention given to variables of genetic interest. Afterwards a sample of it was investigated in relation to 22 genetic systems. The community can be characterized as a young group, with high fertility, but moderate mortality and endogamy. The index of opportunity for selection is relatively low (0.46). The presence of variation at the ABO and Lutheran loci suggests some non-Indian admixture, calculated as 7% in the sample studied. Unusual findings were the absence of L^*NS, low frequency (7%) of L^*MS and high frequency (37%) of L^*Ns. They also showed low frequencies of P^*1 (28%) and DI^*a (3%), but high of HP^*1 (74%). Similarities, but also differences, were noted with previous results obtained in this tribe in Argentina and Chile.