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1.
Braz J Biol ; 84: e282174, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38836803

RESUMO

The elemental status of cattle is one of the important factors, which determine its growth, fertility, fetal development, meat and dairy production, etc. Therefore, the study of content of different elements in cattle organs and tissues and its correlation with cattle characteristics and diet is urgent task. It is also important to develop intravital and low-invasive methods to analyze element content in cattle to regulate its diet during lifetime. In the present work, we have studied the content and distribution of manganese in Hereford cattle from an ecologically clean zone of Western Siberia (Russia). 252 samples were taken from 31 bulls aged 15-18 months. They were collected from various livestock farms in the region and analyzed using atomic absorption spectrophotometry (organs and muscle tissue) and inductively coupled plasma atomic emission spectrometry (hair). The median values of manganese concentration obtained in natural moisture for hair, heart, kidneys, liver, lungs, muscles, spleen, testes, and brain were 25, 0.37, 1.0, 2.6, 0.4, 0.2, 0.4, 0.5, and 0.5 ppm. Accordingly, the concentration of manganese differs significantly in the organs and tissues of animals (H = 188.6, df = 8, p <0.0001). Statistically significant associations of manganese were revealed in pairs: liver-testis, hair-testis, spleen-testis, and heart-brain. The classification of organs and tissues of animals according to the level of content and variability of manganese is carried out. The concentration of manganese in the body is not uniform, most of all it is deposited in the hair and excretory organs of the liver and kidneys. In other organs and muscle tissues, the distribution of manganese is more even and is in the range of 0.2-0.5 ppm. The resulting ranges can be used as a guideline for Hereford cattle bred in Western Siberia.


Assuntos
Manganês , Espectrofotometria Atômica , Animais , Manganês/análise , Bovinos , Masculino , Sibéria , Cabelo/química , Distribuição Tecidual
2.
Science ; 365(6449)2019 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-31296740

RESUMO

North and South America were the last continents to be explored and settled by modern humans at the end of the Pleistocene. Genetic data, derived from contemporary populations and ancient individuals, show that the first Americans originated from Asia and after several population splits moved south of the continental ice sheets that covered Canada sometime between ~17.5 and ~14.6 thousand years (ka) ago. Archaeological evidence shows that geographically dispersed populations lived successfully, using biface, blade, and osseous technologies, in multiple places in North and South America between ~15.5 and ~14 ka ago. Regional archaeological complexes emerged by at least ~13 ka ago in North America and ~12.9 ka ago in South America. Current genetic and archaeological data do not support an earlier (pre-17.5 ka ago) occupation of the Americas.


Assuntos
Emigração e Imigração/história , Fluxo Gênico , Indígenas Norte-Americanos/genética , Indígenas Norte-Americanos/história , Antropologia , Arqueologia , Ásia/etnologia , História Antiga , Humanos , América do Norte , Sibéria/etnologia , América do Sul
3.
Science ; 362(6419)2018 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-30409807

RESUMO

Studies of the peopling of the Americas have focused on the timing and number of initial migrations. Less attention has been paid to the subsequent spread of people within the Americas. We sequenced 15 ancient human genomes spanning from Alaska to Patagonia; six are ≥10,000 years old (up to ~18× coverage). All are most closely related to Native Americans, including those from an Ancient Beringian individual and two morphologically distinct "Paleoamericans." We found evidence of rapid dispersal and early diversification that included previously unknown groups as people moved south. This resulted in multiple independent, geographically uneven migrations, including one that provides clues of a Late Pleistocene Australasian genetic signal, as well as a later Mesoamerican-related expansion. These led to complex and dynamic population histories from North to South America.


Assuntos
Genoma Humano , Migração Humana , Indígenas Norte-Americanos/genética , Conjuntos de Dados como Assunto , Ásia Oriental/etnologia , Genômica , Humanos , América do Norte , Polimorfismo de Nucleotídeo Único , Dinâmica Populacional , Sibéria/etnologia , América do Sul
4.
Mem. Inst. Oswaldo Cruz ; 112(5): 387-390, May 2017. graf
Artigo em Inglês | LILACS | ID: biblio-841793

RESUMO

We present an arhaeoparasitological analysis of a unique burial from the Neftprovod II burial ground in East Siberia, which dated from the Bronze Age. Analysis of a sediment sample from the sacral region of the pelvis revealed the presence of Taenia sp. eggs. Because uncooked animal tissue is the primary source of Taenia, this indicated that the individual was likely consuming raw or undercooked meat of roe deer, red deer, or elk infected with Taenia. This finding represents the oldest case of a human infected with Taenia sp. from Eastern Siberia and Russia.


Assuntos
Humanos , Animais , Paleopatologia , Taenia/isolamento & purificação , História Antiga , Sibéria , Sepultamento , Rios
5.
Mem Inst Oswaldo Cruz ; 112(5): 387-390, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28443983

RESUMO

We present an arhaeoparasitological analysis of a unique burial from the Neftprovod II burial ground in East Siberia, which dated from the Bronze Age. Analysis of a sediment sample from the sacral region of the pelvis revealed the presence of Taenia sp. eggs. Because uncooked animal tissue is the primary source of Taenia, this indicated that the individual was likely consuming raw or undercooked meat of roe deer, red deer, or elk infected with Taenia. This finding represents the oldest case of a human infected with Taenia sp. from Eastern Siberia and Russia.


Assuntos
Paleopatologia , Taenia/isolamento & purificação , Animais , Sepultamento , História Antiga , Humanos , Rios , Sibéria
6.
Biol Res ; 49(1): 42, 2016 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-27776532

RESUMO

BACKGROUND: Heavy metals can cause great harm to Siberian tigers in the natural environment. Cadmium (Cd2+) is an environmental contaminant that affects multiple cellular processes, including cell proliferation, differentiation, and survival. It has been shown to induce apoptosis in a variety of cell types and tissues. RESULTS: We investigated the apoptotic effects of Cd2+ on Siberian tiger fibroblasts in vitro. Our research revealed the typical signs of apoptosis after Cd2+ exposure. Apoptosis was dose- (0-4.8 µM) and duration-dependent (12-48 h), and proliferation was strongly inhibited. Cd2+ increased the activity of caspase-3, -8, and -9 and disrupted calcium homeostasis by causing oxidative stress and mitochondrial dysfunction. It also increased K+ efflux and altered the mRNA levels of Bax, Bcl-2, caspase-3, caspase-8, Fas, and p53. CONCLUSIONS: Our results suggest that Cd2+ triggers the apoptosis of Siberian tiger fibroblasts by disturbing intracellular homeostasis. These results will aid in our understanding of the effects of Cd2+ on Siberian tigers and in developing interventions to treat and prevent cadmium poisoning.


Assuntos
Apoptose/efeitos dos fármacos , Cádmio/toxicidade , Fibroblastos/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Espaço Intracelular/efeitos dos fármacos , Tigres , Animais , Apoptose/genética , Caspases/análise , Caspases/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Células Cultivadas , Ensaio Cometa/veterinária , Dano ao DNA , Fibroblastos/fisiologia , Homeostase/fisiologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Reação em Cadeia da Polimerase , Espécies Reativas de Oxigênio/análise , Transcrição Reversa , Sibéria
8.
Nature ; 532(7598): 232-5, 2016 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-27049941

RESUMO

As the last habitable continent colonized by humans, the site of multiple domestication hotspots, and the location of the largest Pleistocene megafaunal extinction, South America is central to human prehistory. Yet remarkably little is known about human population dynamics during colonization, subsequent expansions, and domestication. Here we reconstruct the spatiotemporal patterns of human population growth in South America using a newly aggregated database of 1,147 archaeological sites and 5,464 calibrated radiocarbon dates spanning fourteen thousand to two thousand years ago (ka). We demonstrate that, rather than a steady exponential expansion, the demographic history of South Americans is characterized by two distinct phases. First, humans spread rapidly throughout the continent, but remained at low population sizes for 8,000 years, including a 4,000-year period of 'boom-and-bust' oscillations with no net growth. Supplementation of hunting with domesticated crops and animals had a minimal impact on population carrying capacity. Only with widespread sedentism, beginning ~5 ka, did a second demographic phase begin, with evidence for exponential population growth in cultural hotspots, characteristic of the Neolithic transition worldwide. The unique extent of humanity's ability to modify its environment to markedly increase carrying capacity in South America is therefore an unexpectedly recent phenomenon.


Assuntos
Migração Humana/história , Dinâmica Populacional/história , Agricultura/história , Arqueologia , Clima , Mapeamento Geográfico , História Antiga , Humanos , Datação Radiométrica , Sibéria/etnologia , América do Sul
9.
Biol. Res ; 49: 1-14, 2016. ilus, graf
Artigo em Inglês | LILACS | ID: biblio-950868

RESUMO

BACKGROUND: Heavy metals can cause great harm to Siberian tigers in the natural environment. Cadmium (Cd2+) is an environmental contaminant that affects multiple cellular processes, including cell proliferation, differentiation, and survival. It has been shown to induce apoptosis in a variety of cell types and tissues. RESULTS: We investigated the apoptotic effects of Cd2+ on Siberian tiger fibroblasts in vitro. Our research revealed the typical signs of apoptosis after Cd²+ exposure. Apoptosis was dose- (0-4.8 µM) and duration-dependent (12-48 h), and proliferation was strongly inhibited. Cd²+ increased the activity of caspase-3, -8, and -9 and disrupted calcium homeostasis by causing oxidative stress and mitochondrial dysfunction. It also increased K+ efflux and altered the mRNA levels of Bax, Bcl-2, caspase-3, caspase-8, Fas, and p53. CONCLUSIONS: Our results suggest that Cd2+ triggers the apoptosis of Siberian tiger fibroblasts by disturbing intracellular homeostasis. These results will aid in our understanding of the effects of Cd2+ on Siberian tigers and in developing interventions to treat and prevent cadmium poisoning.


Assuntos
Animais , Cádmio/toxicidade , Apoptose/efeitos dos fármacos , Espaço Intracelular/efeitos dos fármacos , Tigres , Fibroblastos/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Sibéria , Dano ao DNA , Ciclo Celular/efeitos dos fármacos , Células Cultivadas , Reação em Cadeia da Polimerase , Espécies Reativas de Oxigênio/análise , Apoptose/genética , Caspases/análise , Caspases/efeitos dos fármacos , Ensaio Cometa/veterinária , Microscopia Eletrônica de Transmissão , Transcrição Reversa , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Fibroblastos/fisiologia , Homeostase/fisiologia
10.
Mem. Inst. Oswaldo Cruz ; 110(8): 974-980, Dec. 2015. graf
Artigo em Inglês | LILACS | ID: lil-769834

RESUMO

We present a paleoparasitological analysis of the medieval Zeleniy Yar burial ground of the XII-XII centuries AD located in the northern part of Western Siberia. Parasite eggs, identified as eggs of Opisthorchis felineus, were found in the samples from the pelvic area of a one year old infant buried at the site. Presence of these eggs in the soil samples from the infant’s abdomen suggests that he/she was infected with opisthorchiasis and imply consumption of undercooked fish. Ethnographic records collected among the population of the northern part of Western Siberia reveal numerous cases of feeding raw fish to their children. Zeleniy Yar case of opisthorchiasis suggests that this dietary custom has persisted from at least medieval times.


Assuntos
Animais , História Medieval , Humanos , Lactente , Cemitérios/história , Doenças Transmitidas por Alimentos/história , Múmias/parasitologia , Opistorquíase/história , Alimentos Crus/parasitologia , Comportamento Alimentar , Peixes/parasitologia , Parasitologia de Alimentos/história , Opisthorchis/isolamento & purificação , Contagem de Ovos de Parasitas/história , Sibéria/etnologia , Zigoto
11.
Mem Inst Oswaldo Cruz ; 110(8): 974-80, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26602874

RESUMO

We present a paleoparasitological analysis of the medieval Zeleniy Yar burial ground of the XII-XII centuries AD located in the northern part of Western Siberia. Parasite eggs, identified as eggs of Opisthorchis felineus, were found in the samples from the pelvic area of a one year old infant buried at the site. Presence of these eggs in the soil samples from the infant's abdomen suggests that he/she was infected with opisthorchiasis and imply consumption of undercooked fish. Ethnographic records collected among the population of the northern part of Western Siberia reveal numerous cases of feeding raw fish to their children. Zeleniy Yar case of opisthorchiasis suggests that this dietary custom has persisted from at least medieval times.


Assuntos
Cemitérios/história , Doenças Transmitidas por Alimentos/história , Múmias/parasitologia , Opistorquíase/história , Alimentos Crus/parasitologia , Animais , Comportamento Alimentar , Peixes/parasitologia , Parasitologia de Alimentos/história , História Medieval , Humanos , Lactente , Opisthorchis/isolamento & purificação , Contagem de Ovos de Parasitas/história , Sibéria/etnologia , Zigoto
13.
Am J Hum Biol ; 26(6): 803-12, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25130760

RESUMO

OBJECTIVES: Changes in sleep patterns often occur in older adults. Previous studies have documented associations between sleep duration, sleep quality, and obesity risk in older individuals, yet few studies have examined these trends in lower-income countries. The present cross-sectional study uses nationally representative datasets from six countries to examine these relationships. METHODS: Two hypotheses related to obesity risk and sleep patterns were tested using data from the first wave of the World Health Organization's Study on global AGEing and adult health (SAGE). This longitudinal study draws on samples of older adults (>50 years old) in six middle-income countries (China, Ghana, India, Mexico, Russian Federation, and South Africa). Self-report data were used to measure sleep duration, sleep quality, lifestyle and sociodemographic information, while anthropometric measurements were collected to assess body mass index (BMI) and waist circumference (WC). Multiple linear regressions were used to examine the relationship between sleep patterns and obesity risk while controlling for lifestyle factors. RESULTS: Shorter sleep durations in both men and women were significantly associated with higher BMI and WC measures (P < 0.05). Low sleep quality did not significantly contribute to increased obesity risk. Surprisingly, high sleep quality was significantly associated with increased male BMI and WC in China and India (P < 0.01). CONCLUSIONS: This study documented an association between short sleep duration and increased obesity risk, which is important given the global increase of obesity-related diseases.


Assuntos
Obesidade/epidemiologia , Transtornos do Sono-Vigília/epidemiologia , Sono , Idoso , Índice de Massa Corporal , China/epidemiologia , Estudos Transversais , Feminino , Gana/epidemiologia , Humanos , Índia/epidemiologia , Estilo de Vida , Modelos Lineares , Estudos Longitudinais , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Análise Multivariada , Risco , Fatores Sexuais , Sibéria/epidemiologia , Fumar/epidemiologia , Fatores Socioeconômicos , África do Sul/epidemiologia , Inquéritos e Questionários , Fatores de Tempo , Circunferência da Cintura
14.
Emerg Infect Dis ; 19(12): 2012-6, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24274336

RESUMO

Powassan virus is endemic to the United States, Canada, and the Russian Far East. We report serologic evidence of circulation of this virus in Alaska, New Mexico, and Siberia. These data support further studies of viral ecology in rapidly changing Arctic environments.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos/classificação , Encefalite Transmitida por Carrapatos/epidemiologia , Alaska/epidemiologia , Animais , Vírus da Encefalite Transmitidos por Carrapatos/genética , Vírus da Encefalite Transmitidos por Carrapatos/imunologia , Geografia Médica , Especificidade de Hospedeiro , Humanos , Mamíferos , New Mexico/epidemiologia , Prevalência , Sorotipagem , Sibéria/epidemiologia
15.
PLoS One ; 8(8): e71390, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23990949

RESUMO

Recent progress in the phylogenetic resolution of the Y-chromosome phylogeny permits the male demographic dynamics and migratory events that occurred in Central and Southern America after the initial human spread into the Americas to be investigated at the regional level. To delve further into this issue, we examined more than 400 Native American Y chromosomes (collected in the region ranging from Mexico to South America) belonging to haplogroup Q - virtually the only branch of the Y phylogeny observed in modern-day Amerindians of Central and South America - together with 27 from Mongolia and Kamchatka. Two main founding lineages, Q1a3a1a-M3 and Q1a3a1-L54(xM3), were detected along with novel sub-clades of younger age and more restricted geographic distributions. The first was also observed in Far East Asia while no Q1a3a1-L54(xM3) Y chromosome was found in Asia except the southern Siberian-specific sub-clade Q1a3a1c-L330. Our data not only confirm a southern Siberian origin of ancestral populations that gave rise to Paleo-Indians and the differentiation of both Native American Q founding lineages in Beringia, but support their concomitant arrival in Mesoamerica, where Mexico acted as recipient for the first wave of migration, followed by a rapid southward migration, along the Pacific coast, into the Andean region. Although Q1a3a1a-M3 and Q1a3a1-L54(xM3) display overlapping general distributions, they show different patterns of evolution in the Mexican plateau and the Andean area, which can be explained by local differentiations due to demographic events triggered by the introduction of agriculture and associated with the flourishing of the Great Empires.


Assuntos
Cromossomos Humanos Y , Haplótipos , Indígenas Centro-Americanos/genética , Indígenas Norte-Americanos/genética , Indígenas Sul-Americanos/genética , Algoritmos , DNA Mitocondrial/genética , Genética Populacional , História Antiga , Humanos , Masculino , Repetições de Microssatélites , Mongólia , Mutação , Filogenia , Sibéria , América do Sul
16.
Hum Biol ; 85(5): 789-96, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25078961

RESUMO

From northeastern Eurasia to the Americas, a three-stage spread of modern humans is considered through large-scale intermittence (exploitation/relocation). Conceptually, this work supports intermittence as a real strategy for colonization of new habitats. For the first stage, northeastern Eurasia travel, we adapt our model to archaeological dates determining the diffusion coefficient (exploitation phase) as D = 299.44 km2/yr and the velocity parameter (relocation phase) as vo = 4.8944 km/yr. The relative phase weight (✧0.46) between both kinds of motions is consistent with a moderate biological population rate (r΄ ✧ 0.0046/yr). The second stage is related to population fragmentation. The last stage, reaching Alaska, corresponds essentially to relocation (vo ✧ 0.75 km/yr).


Assuntos
Emigração e Imigração/história , Alaska , América , Arqueologia , Ásia , História Antiga , Humanos , Modelos Teóricos , Dinâmica Populacional/história , Sibéria
17.
BMC Evol Biol ; 11: 293, 2011 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-21978175

RESUMO

BACKGROUND: The Asian origin of Native Americans is largely accepted. However uncertainties persist regarding the source population(s) within Asia, the divergence and arrival time(s) of the founder groups, the number of expansion events, and migration routes into the New World. mtDNA data, presented over the past two decades, have been used to suggest a single-migration model for which the Beringian land mass plays an important role. RESULTS: In our analysis of 568 mitochondrial genomes, the coalescent age estimates of shared roots between Native American and Siberian-Asian lineages, calculated using two different mutation rates, are A4 (27.5 ± 6.8 kya/22.7 ± 7.4 kya), C1 (21.4 ± 2.7 kya/16.4 ± 1.5 kya), C4 (21.0 ± 4.6 kya/20.0 ± 6.4 kya), and D4e1 (24.1 ± 9.0 kya/17.9 ± 10.0 kya). The coalescent age estimates of pan-American haplogroups calculated using the same two mutation rates (A2:19.5 ± 1.3 kya/16.1 ± 1.5 kya, B2:20.8 ± 2.0 kya/18.1 ± 2.4 kya, C1:21.4 ± 2.7 kya/16.4 ± 1.5 kya and D1:17.2 ± 2.0 kya/14.9 ± 2.2 kya) and estimates of population expansions within America (~21-16 kya), support the pre-Clovis occupation of the New World. The phylogeography of sublineages within American haplogroups A2, B2, D1 and the C1b, C1c and C1d subhaplogroups of C1 are complex and largely specific to geographical North, Central and South America. However some sub-branches (B2b, C1b, C1c, C1d and D1f) already existed in American founder haplogroups before expansion into the America. CONCLUSIONS: Our results suggest that Native American founders diverged from their Siberian-Asian progenitors sometime during the last glacial maximum (LGM) and expanded into America soon after the LGM peak (~20-16 kya). The phylogeography of haplogroup C1 suggest that this American founder haplogroup differentiated in Siberia-Asia. The situation is less clear for haplogroup B2, however haplogroups A2 and D1 may have differentiated soon after the Native American founders divergence. A moderate population bottle neck in American founder populations just before the expansion most plausibly resulted in few founder types in America. The similar estimates of the diversity indices and Bayesian skyline analysis in North America, Central America and South America suggest almost simultaneous (~ 2.0 ky from South to North America) colonization of these geographical regions with rapid population expansion differentiating into more or less regional branches across the pan-American haplogroups.


Assuntos
Povo Asiático/genética , DNA Mitocondrial/genética , Genoma Mitocondrial , Indígenas Norte-Americanos/genética , Americanos Mexicanos/genética , Filogenia , Teorema de Bayes , América Central , Haplótipos , Humanos , Taxa de Mutação , América do Norte , Filogeografia , Sibéria , América do Sul
18.
Proc Biol Sci ; 278(1718): 2568-74, 2011 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-21270029

RESUMO

Intercontinental dispersal via land bridge connections has been important in the biogeographic history of many Holarctic plant and animal groups. Likewise, some groups appear to have accomplished trans-oceanic dispersal via rafting. Dibamid lizards are a clade of poorly known fossorial, essentially limbless species traditionally split into two geographically disjunct genera: Dibamus comprises approximately 20 Southeast Asian species, many of which have very limited geographical distributions, and the monotypic genus Anelytropsis occupies a small area of northeastern Mexico. Although no formal phylogeny of the group exists, a sister-taxon relationship between the two genera has been assumed based on biogeographic considerations. We used DNA sequence data from one mitochondrial and six nuclear protein-coding genes to construct a phylogeny of Dibamidae and to estimate divergence times within the group. Surprisingly, sampled Dibamus species form two deeply divergent, morphologically conserved and geographically concordant clades, one of which is the sister taxon of Anelytropsis papillosus. Our analyses indicate Palaearctic to Nearctic Beringian dispersal in the Late Palaeocene to Eocene. Alternatively, a trans-Pacific rafting scenario would extend the upper limit on dispersal to the Late Cretaceous. Either scenario constitutes a remarkable long-distance dispersal in what would seem an unlikely candidate.


Assuntos
Migração Animal , Lagartos/genética , Lagartos/fisiologia , Filogenia , Alaska , Animais , Sudeste Asiático , DNA Mitocondrial/genética , Evolução Molecular , Lagartos/classificação , México , Proteínas Nucleares/genética , Filogeografia , Análise de Sequência de DNA , Sibéria , Especificidade da Espécie
19.
Homeopathy ; 99(4): 278-83, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20970098

RESUMO

Health is a fundamental human right which contributes to reducing poverty, and encourages social development, human safety, and economic growth. International initiatives have fallen far short of their goals. This paper describes collaboration between the region of Tuscany and Cuba, Western Sahara, Senegal and Serbia. These have introduced various forms of Complementary and Alternative Medicine, including homeopathy and Traditional Chinese Medicine into primary healthcare particularly obstetrics, and into veterinary medicine. Complementary and traditional medicine can represent a useful and sustainable resource in various fields of health care. Inclusion in the public health system must go hand in hand with scientific evaluation.


Assuntos
Prestação Integrada de Cuidados de Saúde/organização & administração , Países em Desenvolvimento , Homeopatia/organização & administração , Disseminação de Informação/métodos , Comunicação Interdisciplinar , Cooperação Internacional , Atenção Primária à Saúde/organização & administração , África do Norte , Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Terapias Complementares/organização & administração , Cuba , Humanos , Itália , Sibéria
20.
Parasitology ; 137(8): 1227-37, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20388235

RESUMO

We analysed data on the abundance and distribution of 26 species of mesostigmate mites with different feeding habits collected from bodies of small mammalian hosts in 2 geographical regions (West Siberia and Argentina). We tested whether prevalence of a mite can be reliably predicted from a simple epidemiological model that takes into account mean abundance and its variance. We theorized that the difference between prevalence predicted from the model and observed prevalence would be smallest in obligatory haematophagous mites, intermediate in facultatively haematophagous mites and greatest in non-haematophagous mites. We also theorized that prevalence of mites from the region with sharp seasonality (Siberia) would be predicted accurately only if host number would be taken into account. We found that the success of a simple epidemiological model to predict prevalence in mites was similar to that reported earlier for other ectoparasitic arthropods. Surprisingly, the model predicted prevalence of obligatory exclusively haematophagous mites less successfully than that of mites with other feeding habits. No difference in the model performance between mites occurring in the 2 geographical regions were found independent of whether the model took the number of hosts into account.


Assuntos
Ectoparasitoses/veterinária , Eulipotyphla/parasitologia , Infestações por Ácaros/veterinária , Modelos Biológicos , Roedores/parasitologia , Animais , Argentina/epidemiologia , Ectoparasitoses/epidemiologia , Ectoparasitoses/parasitologia , Interações Hospedeiro-Parasita , Infestações por Ácaros/epidemiologia , Infestações por Ácaros/parasitologia , Ácaros/fisiologia , Valor Preditivo dos Testes , Prevalência , Estações do Ano , Sibéria/epidemiologia
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