943 resultados para Armenian Americans


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Citocinas são moléculas que controlam e modulam a atividade de numerosas células por se ligarem a seus receptores específicos. As diferenças observadas na produção de citocinas entre indivíduos podem ser, pelo menos em parte, explicadas pelos polimorfismos genéticos como o polimorfismo de um único nucleotídeo (SNP). Em 181 indivíduos saudáveis não-aparentados da cidade do Rio de Janeiro (região Sudeste - Brasil), nós analisamos os polimorfismos de citocinas em genes que codificam para Fator de Necrose Tumoral-alfa (TNF-a), Fator de Crescimento Transformante-beta (TGF-b), Interleucina-10, Interleucina-6 e Interferon-gama (IFN-g). Reação em cadeia da polimerase utilizando-se iniciadores sequencia-específicos foi realizada com auxílio do kit comercial CytGen (One Lambda Inc. Canoga Park, CA, USA). Ao todo, 8 polimorfismos foram analisados: TNF-a (-308G/A); TGF-b (códon 10C/T, códon 25C/G); IL-10 (-1082A/G, -819T/C, -592A/C); IL-6 (-174C/G) e IFN-g (+874T/A). Os dados observados foram comparados a três grupos de população de diferentes regiões do Brasil (São Paulo, Paraná e Bahia) e a três populações de outros continentes (Itália, Eslováquia e Negros Norte-Americanos). O teste qui-quadrado foi utilizado para as comparações. Nossa análise da população do Rio de Janeiro mostrou que os as freqüências alélicas em IL-10, IL-6 e IFN-g são desigualmente distribuídos entre Brancos, Mulatos e Negros (p<0,05). A comparação com populações de outras regiões do Brasil revelou que Rio de Janeiro e Bahia possuem freqüências alélicas e genotípicas de TGF-b (códon 25) estatisticamente diferentes (p=0,004 e p=0,002, respectivamente). Ainda, a freqüência alélica na população do Rio de Janeiro é significativamente diferente quando comparada à população da Itália [IL-6 (-174), p=0,0092; e IFN-g (+874) p=0,0418)]; Eslováquia [IL-10(-1082), p=0,006; IL-6(-174), p=0,0002; e IFN-g(+874), p=0,0335]; e Afro-Americanos [IL-10(-819), p=0,0446; IL-6(-174), p<0,0001; e IFN-g(+874), p<0,0001]. Adicionalmente, observamos que a diferença na distribuição dos haplótipos em IL-10 (-1082/-819/-592) na população do Rio de Janeiro em comparação com a da Itália (p=0,0293) e Afro-Americanos (p=0,0025) é significativa. Portanto, concluímos que os polimorfismos em IL-10, IL-6 e IFN-g estão distribuídos de acordo com a etnia na população do Rio de Janeiro. A população do Rio de Janeiro possui freqüências de polimorfismos diferentes das populações de Bahia, Itália, Eslováquia e Afro-Americanos, mas semelhantes à população de São Paulo/Paraná. Nossas observações poderão ser úteis para futuros estudos e associação entre polimorfismos genéticos de citocinas e doenças na população do Rio de Janeiro.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

As porções uniparentais do genoma humano, representadas pelo cromossomo Y e pelo DNA mitocondrial (DNAmt), contêm informação genética relacionada às heranças patrilinear e matrilinear, respectivamente. Além da aplicabilidade em genética médica e forense, o DNAmt tem sido utilizado como um importante marcador molecular em estudos sobre evolução para traçar inferências filogenéticas e filogeográficas sobre as populações humanas. A análise de linhagens de DNAmt presentes em diferentes populações mundiais levou à identificação de haplogrupos reunindo diversos haplótipos específicos dos grandes grupos étnicos: africanos, europeus, asiáticos e nativos americanos. A população brasileira é conhecida como uma das mais heterogêneas do mundo, resultado do processo de colonização do país, abrangendo mais de cinco séculos de miscigenação entre povos de diferentes continentes. Este trabalho teve como objetivo estimar a partir da análise do DNA mitocondrial as proporções ancestrais africanas, européias e ameríndias na população do Rio de Janeiro. Para isso foram sequencidas as regiões hipervariáveis HVI e HVII do DNAmt de 109 indivíduos não relacionados geneticamente residentes no Rio de Janeiro. Os haplogrupos foram classificados de acordo com o conjunto de polimorfismos dos haplótipos individuais. Programas estatísticas foram utilizados para a determinação de parâmetros de diversidade genética e comparações populacionais. A diversidade haplotípica foi estimada em 0,9988. Nossos resultados demonstraram na população do Rio de Janeiro percentuais de cerca de 60%, 25% e 15% de ancestralidades maternas africana, ameríndia e européia, respectivamente. Através da análise de distâncias genéticas, evidenciou-se que a população do Rio de Janeiro está mais próxima das populações brasilerias dos estados de São Paulo e Alagoas. Como descrito nos registros históricos, algumas regiões do país tiveram processos de colonização muito específicos que se refletem nas proporções ancestrais maternas e paternas observadas. Em relação ao DNAmt, não se verificou diferença genética significativa entre as populações do Rio de Janeiro e a de Angola, uma população africana. Os resultados obtidos estão em estreita concordância com os registros históricos e outros estudos genéticos acerca da formação da população brasileira

Relevância:

10.00% 10.00%

Publicador:

Resumo:

As relações sino-americanas passaram a desempenhar um papel ordenador fundamental na condução dos assuntos internacionais neste século XXI, ao ponto de alguns analistas criarem o termo G-2. A crise financeira de 2008, por representar um golpe profundo nos países desenvolvidos e nos direcionamentos de valores do estágio atual de desenvolvimento do sistema, levou a relação China-Estados Unidos a um outro patamar. Ao passo que os norte-americanos tiveram de se preocupar em resolver as turbulências causadas na economia doméstica, o país asiático passou a desempenhar um papel crucial no processo de recuperação da economia global. O presente trabalho tem o objetivo, então, de analisar de que forma a crise de 2008, também chamada de crise do subprime, impactou os ordenamentos centrais do Sistema Internacional neste período de recuperação e como as relações sino-americanas podem ser usadas para uma melhor compreensão deste fenômeno. Na busca por traçar respostas mais sólidas, a pesquisa delineia-se em três frentes principais de análise: as relações diretas entre China e Estados Unidos; as relações dos dois países com um terceiro ator, a saber, a África; e os posicionamentos adotados por ambas as partes nas instituições multilaterais. Para tal, primeiro buscou-se aliar análises qualitativas e quantitativas, baseadas em instrumentais matemáticos e também na Ciência Política, História e Economia Política Internacional, para alcançar os resultados definidos nos objetivos da pesquisa. A dissertação é dividida em cinco capítulos, onde os três primeiros tratam de introduzir o assunto estudado e as principais vertentes teóricas utilizadas ao longo do trabalho. Os últimos envolvem a aplicação prática dos conceitos interdisciplinares escolhidos como aliados do trabalho empírico e a apresentação dos resultados finais. Em linhas gerais, concluiu-se que a crise acentuou os aspectos de interdependência entre China e Estados Unidos em todas as frentes estudadas. Avaliando as relações sino-americanas e os rumos do sistema internacional pós-crise em três facetas, concluímos também que tal exercício analítico ofereceu recursos mais palpáveis no fornecimento das respostas procuradas pela dissertação.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Os miomas uterinos (MU) são considerados os tumores mais comumente encontrados no sistema reprodutor feminino. Este estudo buscou investigar associação entre o ganho de peso na idade adulta e a ocorrência de miomas. Esta relação foi explorada em estudos internacionais na maior parte americanos. No Brasil nenhum estudo havia abordado este tema até o término desta dissertação. Para investigar como a associação entre o ganho de peso na idade adulta afeta o risco de miomas, foi conduzido um estudo transversal referente aos dados da linha de base (1999-2001) do estudo longitudinal Pró-Saúde onde 2594 servidores técnico-administrativos de uma universidade pública do Rio de Janeiro são participantes, entre eles foram selecionadas 1560 mulheres com diagnóstico médico autorrelatado de MU e que tiveram seus pesos aos vinte anos de idade autorrelatados em questionário autopreenchível cujas idades variaram entre 22 a 67 anos. Foi avaliada a mudança de peso desde os 20 anos até o momento da entrada no estudo. As prevalências de miomas encontradas neste grupo foram23.3% (IC95% - 21,2; 25,4), situando-se em posição intermediária quando comparada as prevalências encontradas nos estudos norte-americanos. A maior prevalência de ganho de peso foi encontrada no 4 quintil cujos valores variaram entre ganho maior que 0,7 Kg/ano e menor que 1,1 Kg/ano. A faixa etária com maiores prevalências de diagnóstico médico auto-relatado de miomas ficou compreendida entre 45 a 54 anos (39,1%).Os valores de peso aos 20 anos informados pelas respondentes variaram entre 30,0 e 96,0 kg. O IMC aos 20 anos de idade se situou está dentro da categoria de normalidade entre a maior parte das participantes. Os resultados não sugerem associação entre o ganho de peso na idade adulta e miomas nesta população de estudo

Relevância:

10.00% 10.00%

Publicador:

Resumo:

280 p.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This article covers the biology and the history of the bay scallop habitats and fishery from Massachusetts to North Carolina. The scallop species that ranges from Massachusetts to New York is Argopecten irradians irradians. In New Jersey, this species grades into A. i. concentricus, which then ranges from Maryland though North Carolina. Bay scallops inhabit broad, shallow bays usually containing eelgrass meadows, an important component in their habitat. Eelgrass appears to be a factor in the production of scallop larvae and also the protection of juveniles, especially, from predation. Bay scallops spawn during the warm months and live for 18–30 months. Only two generations of scallops are present at any time. The abundances of each vary widely among bays and years. Scallops were harvested along with other mollusks on a small scale by Native Americans. During most of the 1800’s, people of European descent gathered them at wading depths or from beaches where storms had washed them ashore. Scallop shells were also and continue to be commonly used in ornaments. Some fishing for bay scallops began in the 1850’s and 1860’s, when the A-frame dredge became available and markets were being developed for the large, white, tasty scallop adductor muscles, and by the 1870’s commercial-scale fishing was underway. This has always been a cold-season fishery: scallops achieve full size by late fall, and the eyes or hearts (adductor muscles) remain preserved in the cold weather while enroute by trains and trucks to city markets. The first boats used were sailing catboats and sloops in New England and New York. To a lesser extent, scallops probably were also harvested by using push nets, picking them up with scoop nets, and anchor-roading. In the 1910’s and 1920’s, the sails on catboats were replaced with gasoline engines. By the mid 1940’s, outboard motors became more available and with them the numbers of fishermen increased. The increases consisted of parttimers who took leaves of 2–4 weeks from their regular jobs to earn extra money. In the years when scallops were abundant on local beds, the fishery employed as many as 10–50% of the towns’ workforces for a month or two. As scallops are a higher-priced commodity, the fishery could bring a substantial amount of money into the local economies. Massachusetts was the leading state in scallop landings. In the early 1980’s, its annual landings averaged about 190,000 bu/yr, while New York and North Carolina each landed about 45,000 bu/yr. Landings in the other states in earlier years were much smaller than in these three states. Bay scallop landings from Massachusetts to New York have fallen sharply since 1985, when a picoplankton, termed “brown tide,” bloomed densely and killed most scallops as well as extensive meadows of eelgrass. The landings have remained low, large meadows of eelgrass have declined in size, apparently the species of phytoplankton the scallops use as food has changed in composition and in seasonal abundance, and the abundances of predators have increased. The North Carolina landings have fallen since cownose rays, Rhinoptera bonsais, became abundant and consumed most scallops every year before the fishermen could harvest them. The only areas where the scallop fishery remains consistently viable, though smaller by 60–70%, are Martha’s Vineyard, Nantucket, Mass., and inside the coastal inlets in southwestern Long Island, N.Y.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The northern quahog, Mercenaria mercenaria, ranges along the Atlantic Coast of North America from the Canadian Maritimes to Florida, while the southern quahog, M. campechiensis, ranges mostly from Florida to southern Mexico. The northern quahog was fished by native North Americans during prehistoric periods. They used the meats as food and the shells as scrapers and as utensils. The European colonists copied the Indians treading method, and they also used short rakes for harvesting quahogs. The Indians of southern New England and Long Island, N.Y., made wampum from quahog shells, used it for ornaments and sold it to the colonists, who, in turn, traded it to other Indians for furs. During the late 1600’s, 1700’s, and 1800’s, wampum was made in small factories for eventual trading with Indians farther west for furs. The quahoging industry has provided people in many coastal communities with a means of earning a livelihood and has given consumers a tasty, wholesome food whether eaten raw, steamed, cooked in chowders, or as stuffed quahogs. More than a dozen methods and types of gear have been used in the last two centuries for harvesting quahogs. They include treading and using various types of rakes and dredges, both of which have undergone continuous improvements in design. Modern dredges are equipped with hydraulic jets and one type has an escalator to bring the quahogs continuously to the boats. In the early 1900’s, most provinces and states established regulations to conserve and maximize yields of their quahog stocks. They include a minimum size, now almost universally a 38-mm shell width, and can include gear limitations and daily quotas. The United States produces far more quahogs than either Canada or Mexico. The leading producer in Canada is Prince Edward Island. In the United States, New York, New Jersey, and Rhode Island lead in quahog production in the north, while Virginia and North Carolina lead in the south. Connecticut and Florida were large producers in the 1990’s. The State of Tabasco leads in Mexican production. In the northeastern United States, the bays with large openings, and thus large exchanges of bay waters with ocean waters, have much larger stocks of quahogs and fisheries than bays with small openings and water exchanges. Quahog stocks in certified beds have been enhanced by transplanting stocks to them from stocks in uncertified waters and by planting seed grown in hatcheries, which grew in number from Massachusetts to Florida in the 1980’s and 1990’s.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The northern quahog, Mercenaria mercenaria, ranges along the Atlantic Coast of North America from the Canadian Maritimes to Florida, while the southern quahog, M. campechiensis, ranges mostly from Florida to southern Mexico. The northern quahog was fished by native North Americans during prehistoric periods. They used the meats as food and the shells as scrapers and as utensils. The European colonists copied the Indians treading method, and they also used short rakes for harvesting quahogs. The Indians of southern New England made wampum from quahog shells, used it for ornaments and sold it to the colonists, who, in turn, traded it to other Indians for furs. During the late 1600’s, 1700’s, and 1800’s, wampum was made in small factories for eventual trading with Indians farther west for furs. The quahoging industry has provided people in many coastal communities with a means of earning a livelihood and has provided consumers with a tasty, wholesome food whether eaten raw, steamed, cooked in chowders, or as stuffed quahogs. More than a dozen methods and types of gear have been used in the last two centuries for harvesting quahogs. They include treading and using various types of rakes and dredges, both of which have undergone continuous improvements in design. Modern dredges are equipped with hydraulic jets and one type has an escalator to bring the quahogs continuously to the boats. In the early 1900’s, most provinces and states established regulations to conserve and maximize yields of their quahog stocks. They include a minimum size, now almost universally a 38-mm shell width, and can include gear limitations and daily quotas. The United States produces far more quahogs than either Canada or Mexico. The leading producer in Canada is Prince Edward Island. In the United States, New York, New Jersey, and Rhode Island lead in quahog production in the north, while Virginia and North Carolina lead in the south. Connecticut and Florida were large producers in the 1990’s. The State of Campeche leads in Mexican production. In the northeastern United States, the bays with large openings, and thus large exchanges of bay waters with ocean waters, have much larger stocks of quahogs and fisheries than bays with small openings and water exchanges. Quahog stocks in certifi ed beds have been enhanced by transplanting stocks to them from stocks in uncertified waters and by planting seed grown in hatcheries, which grew in number from Massachusetts to Florida in the 1980’s and 1990’s.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The exploitation of California sea lions, Zalophus californianus, in Mexican waters can be divided into four periods as defined by political characteristics of the country: Prehispanic, Colonial, Independent, and Postrevolutionary. During the first period (pre 1533), Native Americans took sea lions at low levels. During the second (1534–1821) and the third (1822–1911) periods, most exploitation was by foreigners and was incidental to other marine mammal harvests. During the Postrevolutionary period (after 1911), sea lions were exploited by Mexican and U.S. citizens for several commercial uses. Exploitation officially ended in 1982, although some small-scale poaching still occurs.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Historically, America's use and enjoyment of the oyster extend far back into prehistoric times. The Native Americans often utilized oysters, more intensively in some areas than in others, and, at least in some areas of the Caribbean and Pacific coast, the invading Spanish sought oysters as eagerly as they did gold-but for the pearls. That was the pearl oyster, Pinctada sp., and signs of its local overexploitation were recorded early in the 16th century. During the 1800's, use of the eastern oyster grew phenomenally and, for a time, it outranked beef as a source of protein in some parts of the nation. Social events grew up around it, as it became an important aspect of culture and myth. Eventually, research on the oyster began to blossom, and scientific literature on the various species likewise bloomed-to the extent that when the late Paul Galtsoff wrote his classic treatise "The American oyster Crassostrea virginica Gmelin" in 1954, he reported compiling an extensive bibliography of over 6,000 subject and author cards on oysters and related subjects which he deposited in the library of the Woods Hole Laboratory of the Bureau of Commercial Fisheries (now NMFS). That large report, volume 64 (480 pages) of the agency's Fishery Bulletin, was a bargain at $2.75, and it has been a standard reference ever since. But the research and the attendant literature have grown greatly since Galtsoff's work was published, and now that has been thoroughly updated.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Fishing was America's first industry, and turtling played an important role in the nation's developing fisheries. However, before the European settlers arrived in the New World, Native Americans had already developed spiritual and gastronomic relationships with sea turtles. There are indications that ancient Florida tribes had eaten sea turtles and then placed the skulls in burial mounds (Johnson, 1952).

Relevância:

10.00% 10.00%

Publicador:

Resumo:

An unequal contribution of male and female lineages from parental populations to admixed ones is not uncommon in the American continents, as a consequence of directional gene flow from European men into African and Hispanic Americans in the past several c

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Background: Human skeletal system has evolved rapidly since the dispersal of modern humans from Africa, potentially driven by selection and adaptation. Osteogenin (BMP3) plays an important role in skeletal development and bone osteogenesis as an antagonist of the osteogenic bone morphogenetic proteins, and negatively regulates bone mineral density. Methodology/Principal Findings: Here, we resequenced the BMP3 gene from individuals in four geographically separated modern human populations. Features supportive of positive selection in the BMP3 gene were found including the presence of an excess of nonsynonymous mutations in modern humans, and a significantly lower genetic diversity that deviates from neutrality. The prevalent haplotypes of the first exon region in Europeans demonstrated features of long-range haplotype homogeneity. In contrast with findings in European, the derived allele SNP Arg192Gln shows higher extended haplotype homozygosity in East Asian. The worldwide allele frequency distribution of SNP shows not only a high-derived allele frequency in Asians, but also in Americans, which is suggestive of functional adaptation. Conclusions/Significance: In conclusion, we provide evidence for recent positive selection operating upon a crucial gene in skeletal development, which may provide new insight into the evolution of the skeletal system and bone development.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Background: It is widely accepted that the ancestors of Native Americans arrived in the New World via Beringia approximately 10 to 30 thousand years ago (kya). However, the arrival time(s), number of expansion events, and migration routes into the Western

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Based on the 16S mitochondrial partial gene sequences of 29 genera, containing 26 from Oedipodidae and one each from Tanaoceridae, Pyrgomorphidae and Tetrigidae (as outgroups), the homologus sequences were compared and phylogenetic analyses were performed. A phylogenetic tree was inferred by neighbor-joining (NJ). The results of sequences compared show that: (i) in a total of 574 bp of Oedipodidae, the number of substituted nucleotides was 265 bp and the average percentages of T, C, A and G were 38.3%, 11.4%, 31.8% and 18.5%, respectively, and the content of A+T (70.1%) was distinctly richer than that of C+G (29.9%); and (ii) the average nucleotide divergence of 16S rDNA sequences among genera of Oedipodidae were 9.0%, among families of Acridoidea were 17.0%, and between superfamilies (Tetrigoidea and Acridoidea) were 23.9%, respectively. The phylogenetic tree indicated: (i) the Oedipodidae was a monophyletic group, which suggested that the taxonomic status of this family was confirmed; (ii) the genus Heteropternis separated from the other Oedipodids first and had another unique sound-producing structure in morphology, which is the type-genus of subfamily Heteropterninae; and (iii) the relative intergeneric relationship within the same continent was closer than that of different continents, and between the Eurasian genera and the African genera, was closer than that between Eurasians and Americans.