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1.
BMC Public Health ; 20(1): 482, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32293391

RESUMO

BACKGROUND: The first 1000 days after conception are a critical period to encourage lifestyle changes to reduce the risk of childhood obesity and early programming of chronic diseases. A healthy lifestyle during pregnancy is also crucial to avoid high post-partum weight retention. Currently, lifestyle changes are not consistently discussed during routine health services in Germany. The objective of this study is to evaluate a novel computer-assisted lifestyle intervention embedded in prenatal visits and infant check-ups. The intervention seeks to reduce lifestyle-related risk factors for overweight and obesity among expecting mothers and their infants. METHODS: The study is designed as a hybrid effectiveness-implementation trial to simultaneously collect data on the effectiveness and implementation of the lifestyle intervention. The trial will take place in eight regions of the German state Baden-Wuerttemberg. Region were matched using propensity score matching. Expecting mothers (n = 1860) will be recruited before 12 weeks of gestation through gynecological practices and followed for 18 months. During 11 routine prenatal visits and infant check-ups gynecologists, midwives and pediatricians provide lifestyle counseling using Motivational Interviewing techniques. The primary outcome measure is the proportion of expecting mothers with gestational weight gain within the recommended range. To understand the process of implementation (focus group) interviews will be conducted with providers and participants of the lifestyle intervention. Additionally, an analysis of administrative data and documents will be carried out. An economic analysis will provide insights into cost and consequences compared to routine health services. DISCUSSION: Findings of this study will add to the evidence on lifestyle interventions to reduce risk for overweight and obesity commenced during pregnancy. Insights gained will contribute to the prevention of early programming of chronic disease. Study results regarding implementation fidelity, adoption, reach and cost-effectiveness of the lifestyle intervention will inform decisions about scale up and public funding. TRIAL REGISTRATION: German Clinical Trials Register (DRKS00013173). Registered 3rd of January 2019, https://www.drks.de.


Assuntos
Estudos de Avaliação como Assunto , Promoção da Saúde/métodos , Estilo de Vida Saudável , Cuidado do Lactente , Obesidade/prevenção & controle , Complicações na Gravidez/prevenção & controle , Cuidado Pré-Natal , Adolescente , Adulto , Aconselhamento , Feminino , Alemanha , Pessoal de Saúde , Humanos , Lactente , Masculino , Mães , Entrevista Motivacional , Sobrepeso/prevenção & controle , Obesidade Infantil/prevenção & controle , Gravidez , Projetos de Pesquisa , Fatores de Risco , Aumento de Peso
2.
Proc Natl Acad Sci U S A ; 110(40): 16151-6, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24043818

RESUMO

The hepatitis B virus (HBV), family Hepadnaviridae, is one of most relevant human pathogens. HBV origins are enigmatic, and no zoonotic reservoirs are known. Here, we screened 3,080 specimens from 54 bat species representing 11 bat families for hepadnaviral DNA. Ten specimens (0.3%) from Panama and Gabon yielded unique hepadnaviruses in coancestral relation to HBV. Full genome sequencing allowed classification as three putative orthohepadnavirus species based on genome lengths (3,149-3,377 nt), presence of middle HBV surface and X-protein genes, and sequence distance criteria. Hepatic tropism in bats was shown by quantitative PCR and in situ hybridization. Infected livers showed histopathologic changes compatible with hepatitis. Human hepatocytes transfected with all three bat viruses cross-reacted with sera against the HBV core protein, concordant with the phylogenetic relatedness of these hepadnaviruses and HBV. One virus from Uroderma bilobatum, the tent-making bat, cross-reacted with monoclonal antibodies against the HBV antigenicity determining S domain. Up to 18.4% of bat sera contained antibodies against bat hepadnaviruses. Infectious clones were generated to study all three viruses in detail. Hepatitis D virus particles pseudotyped with surface proteins of U. bilobatum HBV, but neither of the other two viruses could infect primary human and Tupaia belangeri hepatocytes. Hepatocyte infection occurred through the human HBV receptor sodium taurocholate cotransporting polypeptide but could not be neutralized by sera from vaccinated humans. Antihepadnaviral treatment using an approved reverse transcriptase inhibitor blocked replication of all bat hepadnaviruses. Our data suggest that bats may have been ancestral sources of primate hepadnaviruses. The observed zoonotic potential might affect concepts aimed at eradicating HBV.


Assuntos
Quirópteros/virologia , Hepadnaviridae/genética , Hepadnaviridae/patogenicidade , Zoonoses/virologia , Animais , Sequência de Bases , Linhagem Celular Tumoral , Reações Cruzadas/imunologia , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Genoma/genética , Vírus da Hepatite B/genética , Hepatócitos/virologia , Humanos , Immunoblotting , Hibridização In Situ , Dados de Sequência Molecular , Análise de Sequência de DNA , Especificidade da Espécie , Tupaiidae
3.
PLoS Pathog ; 9(6): e1003438, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23818848

RESUMO

Hepatitis C virus (HCV) is among the most relevant causes of liver cirrhosis and hepatocellular carcinoma. Research is complicated by a lack of accessible small animal models. The systematic investigation of viruses of small mammals could guide efforts to establish such models, while providing insight into viral evolutionary biology. We have assembled the so-far largest collection of small-mammal samples from around the world, qualified to be screened for bloodborne viruses, including sera and organs from 4,770 rodents (41 species); and sera from 2,939 bats (51 species). Three highly divergent rodent hepacivirus clades were detected in 27 (1.8%) of 1,465 European bank voles (Myodes glareolus) and 10 (1.9%) of 518 South African four-striped mice (Rhabdomys pumilio). Bats showed anti-HCV immunoblot reactivities but no virus detection, although the genetic relatedness suggested by the serologic results should have enabled RNA detection using the broadly reactive PCR assays developed for this study. 210 horses and 858 cats and dogs were tested, yielding further horse-associated hepaciviruses but none in dogs or cats. The rodent viruses were equidistant to HCV, exceeding by far the diversity of HCV and the canine/equine hepaciviruses taken together. Five full genomes were sequenced, representing all viral lineages. Salient genome features and distance criteria supported classification of all viruses as hepaciviruses. Quantitative RT-PCR, RNA in-situ hybridisation, and histopathology suggested hepatic tropism with liver inflammation resembling hepatitis C. Recombinant serology for two distinct hepacivirus lineages in 97 bank voles identified seroprevalence rates of 8.3 and 12.4%, respectively. Antibodies in bank vole sera neither cross-reacted with HCV, nor the heterologous bank vole hepacivirus. Co-occurrence of RNA and antibodies was found in 3 of 57 PCR-positive bank vole sera (5.3%). Our data enable new hypotheses regarding HCV evolution and encourage efforts to develop rodent surrogate models for HCV.


Assuntos
Evolução Molecular , Genoma Viral , Hepacivirus , Anticorpos Anti-Hepatite C/sangue , Hepatite C , Hepatite Animal , RNA Viral , Roedores , Animais , Sequência de Bases , Gatos , Cães , Hepacivirus/genética , Hepacivirus/metabolismo , Hepatite C/sangue , Hepatite C/genética , Hepatite C/virologia , Hepatite Animal/sangue , Hepatite Animal/genética , Hepatite Animal/virologia , Cavalos , Dados de Sequência Molecular , RNA Viral/sangue , RNA Viral/genética , Roedores/sangue , Roedores/virologia
5.
J Virol ; 86(17): 9134-47, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22696648

RESUMO

Hepatitis E virus (HEV) is one of the most common causes of acute hepatitis in tropical and temperate climates. Tropical genotypes 1 and 2 are associated with food-borne and waterborne transmission. Zoonotic reservoirs (mainly pigs, wild boar, and deer) are considered for genotypes 3 and 4, which exist in temperate climates. In view of the association of several zoonotic viruses with bats, we analyzed 3,869 bat specimens from 85 different species and from five continents for hepevirus RNA. HEVs were detected in African, Central American, and European bats, forming a novel phylogenetic clade in the family Hepeviridae. Bat hepeviruses were highly diversified and comparable to human HEV in sequence variation. No evidence for the transmission of bat hepeviruses to humans was found in over 90,000 human blood donations and individual patient sera. Full-genome analysis of one representative virus confirmed formal classification within the family Hepeviridae. Sequence- and distance-based taxonomic evaluations suggested that bat hepeviruses constitute a distinct genus within the family Hepeviridae and that at least three other genera comprising human, rodent, and avian hepeviruses can be designated. This may imply that hepeviruses invaded mammalian hosts nonrecently and underwent speciation according to their host restrictions. Human HEV-related viruses in farmed and peridomestic animals might represent secondary acquisitions of human viruses, rather than animal precursors causally involved in the evolution of human HEV.


Assuntos
Quirópteros/virologia , Vírus da Hepatite E/genética , Vírus da Hepatite E/isolamento & purificação , Hepatite E/veterinária , Hepatite E/virologia , África , América , Animais , Ásia , Austrália , Quirópteros/classificação , Europa (Continente) , Fezes/virologia , Variação Genética , Genótipo , Vírus da Hepatite E/classificação , Hepevirus/classificação , Hepevirus/genética , Hepevirus/isolamento & purificação , Humanos , Dados de Sequência Molecular , Fases de Leitura Aberta , Filogenia , Proteínas Virais/genética , Zoonoses/classificação , Zoonoses/virologia
6.
PLoS One ; 6(5): e19601, 2011 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-21573178

RESUMO

Treatment of EGFR-mutant non-small cell lung cancer patients with the tyrosine kinase inhibitors erlotinib or gefitinib results in high response rates and prolonged progression-free survival. Despite the development of sensitive mutation detection approaches, a thorough validation of these in a clinical setting has so far been lacking. We performed, in a clinical setting, a systematic validation of dideoxy 'Sanger' sequencing and pyrosequencing against massively parallel sequencing as one of the most sensitive mutation detection technologies available. Mutational annotation of clinical lung tumor samples revealed that of all patients with a confirmed response to EGFR inhibition, only massively parallel sequencing detected all relevant mutations. By contrast, dideoxy sequencing missed four responders and pyrosequencing missed two responders, indicating a dramatic lack of sensitivity of dideoxy sequencing, which is widely applied for this purpose. Furthermore, precise quantification of mutant alleles revealed a low correlation (r(2) = 0.27) of histopathological estimates of tumor content and frequency of mutant alleles, thereby questioning the use of histopathology for stratification of specimens for individual analytical procedures. Our results suggest that enhanced analytical sensitivity is critically required to correctly identify patients responding to EGFR inhibition. More broadly, our results emphasize the need for thorough evaluation of all mutation detection approaches against massively parallel sequencing as a prerequisite for any clinical implementation.


Assuntos
Benchmarking , Análise Mutacional de DNA/métodos , Análise Mutacional de DNA/normas , Neoplasias Pulmonares/genética , Mutação/genética , Adulto , Idoso , Sequência de Bases , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Receptores ErbB/genética , Éxons/genética , Feminino , Genoma Humano/genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Resultado do Tratamento
7.
PLoS One ; 6(12): e29140, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22216187

RESUMO

Bats, a globally distributed group of mammals with high ecological importance, are increasingly recognized as natural reservoir hosts for viral agents of significance to human and animal health. In the present study, we evaluated pools of blood samples obtained from two phylogenetically distant bat families, in particular from flying foxes (Pteropodidae), Eidolon helvum in West Africa, and from two species of New World leaf-nosed fruit bats (Phyllostomidae), Artibeus jamaicensis and Artibeus lituratus in Central America. A sequence-independent virus discovery technique (VIDISCA) was used in combination with high throughput sequencing to detect two novel parvoviruses: a PARV4-like virus named Eh-BtPV-1 in Eidolon helvum from Ghana and the first member of a putative new genus in Artibeus jamaicensis from Panama (Aj-BtPV-1). Those viruses were circulating in the corresponding bat colony at rates of 7-8%. Aj-BtPV-1 was also found in Artibeus lituratus (5.5%). Both viruses were detected in the blood of infected animals at high concentrations: up to 10E8 and to 10E10 copies/ml for Aj-BtPV-1 and Eh-BtPV-1 respectively. Eh-BtPV-1 was additionally detected in all organs collected from bats (brain, lungs, liver, spleen, kidneys and intestine) and spleen and kidneys were identified as the most likely sites where viral replication takes place. Our study shows that bat parvoviruses share common ancestors with known parvoviruses of humans and livestock. We also provide evidence that a variety of Parvovirinae are able to cause active infection in bats and that they are widely distributed in these animals with different geographic origin, ecologies and climatic ranges.


Assuntos
Quirópteros/virologia , Parvovirus/isolamento & purificação , Animais , Sequência de Bases , Primers do DNA , Parvovirus/classificação , Filogenia , Especificidade da Espécie
8.
Naturwissenschaften ; 97(10): 883-90, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20697882

RESUMO

Testosterone mediates male reproductive trade-offs in vertebrates including mammals. In male edible dormice (Glis glis), reproductivity linked to high levels of testosterone reduces their ability to express torpor, which may be expected to dramatically increase thermoregulatory costs. Aims of this study were therefore to analyse behavioural and physiological consequences of reproductive activity in male edible dormice under ecologically and evolutionary relevant conditions in the field. As we frequently encountered sleeping groups in the field, we hypothesized that social thermoregulation should be an important measure to reduce energy expenditure especially in sexually active male edible dormice. Our results revealed that the occurrence of sleeping groups was negatively influenced by male body mass but not by reproductive status or ambient temperature. In reproductive as in non-reproductive males, the number of individuals huddling together was negatively influenced by their body mass. Thus in general males with a high body mass were sitting in smaller groups than males with a low body mass. However, in reproductive males group size was further negatively affected by ambient temperature and positively by testes size. Thus breeders formed larger sleeping groups at lower ambient temperatures and males with larger testes were found in larger groups than males with smaller testes. Measurements of oxygen consumption demonstrated that grouping behaviour represents an efficient strategy to reduce energy expenditure in edible dormice as it reduced energy requirements by almost 40%. In summary, results of this field study showcase how sexually active male edible dormice may, through behavioural adjustment, counterbalance high thermoregulatory costs associated with reproductive activity.


Assuntos
Myoxidae/fisiologia , Reprodução/fisiologia , Animais , Comportamento Animal , Regulação da Temperatura Corporal , Metabolismo Energético , Hibernação , Masculino , Myoxidae/metabolismo , Myoxidae/psicologia , Consumo de Oxigênio , Estações do Ano , Comportamento Sexual Animal , Comportamento Social
9.
Biol Lett ; 5(6): 758-61, 2009 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-19689980

RESUMO

Males of many vertebrate species aggressively defend their reproductive interests by monopolizing females, and the 'challenge hypothesis' predicts that testosterone levels in reproductive contexts rise to facilitate males' competitive behaviours necessary for meeting social challenges. The hypothesis is successful in explaining patterns of testosterone secretion in many avian species, but remains comparatively unexplored in mammals. 'Circulating plasma testosterone levels (T)' were studied in relation to harem maintenance in grey-headed flying-foxes, Pteropus poliocephalus. In this species, harems provide mating opportunities and so a male's ability to maintain a harem is likely to correlate with his fitness. We hypothesized that if T reflect a male's ability to withstand challenges from competitors, then T should be linked to successful harem maintenance. To test this, we temporarily removed males from their territories prior to and during the short mating period, recording their harem sizes both before removal and after reintroduction. Most males successfully reclaimed their territory and a harem, but during the mating period, males with higher T had harems closer to their original size, and males with lower T suffered reduction in harem size. Our findings highlight the role of T in harem maintenance in a major mammalian taxon with complex forms of social organization.


Assuntos
Quirópteros/sangue , Comportamento Competitivo , Comportamento Sexual Animal , Testosterona/sangue , Animais , Feminino , Masculino , Territorialidade
10.
Proc Biol Sci ; 275(1633): 419-25, 2008 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-18048286

RESUMO

Little is known about the effects of temperature extremes on natural systems. This is of increasing concern now that climate models predict dramatic increases in the intensity, duration and frequency of such extremes. Here we examine the effects of temperature extremes on behaviour and demography of vulnerable wild flying-foxes (Pteropus spp.). On 12 January 2002 in New South Wales, Australia, temperatures exceeding 42 degrees C killed over 3500 individuals in nine mixed-species colonies. In one colony, we recorded a predictable sequence of thermoregulatory behaviours (wing-fanning, shade-seeking, panting and saliva-spreading, respectively) and witnessed how 5-6% of bats died from hyperthermia. Mortality was greater among the tropical black flying-fox, Pteropus alecto (10-13%) than the temperate grey-headed flying-fox, Pteropus poliocephalus (less than 1%), and young and adult females were more affected than adult males (young, 23-49%; females, 10-15%; males, less than 3%). Since 1994, over 30000 flying-foxes (including at least 24500 P. poliocephalus) were killed during 19 similar events. Although P. alecto was relatively less affected, it is currently expanding its range into the more variable temperature envelope of P. poliocephalus, which increases the likelihood of die-offs occurring in this species. Temperature extremes are important additional threats to Australian flying-foxes and the ecosystem services they provide, and we recommend close monitoring of colonies where temperatures exceeding 42.0 degrees C are predicted. The effects of temperature extremes on flying-foxes highlight the complex implications of climate change for behaviour, demography and species survival.


Assuntos
Regulação da Temperatura Corporal/fisiologia , Quirópteros/fisiologia , Clima , Efeito Estufa , Mortalidade , Temperatura , Fatores Etários , Animais , Feminino , Geografia , Masculino , New South Wales , Observação , Dinâmica Populacional , Fatores Sexuais
11.
Int J Cardiol ; 114(1): 34-40, 2007 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-16644043

RESUMO

BACKGROUND: Angiotensin II (Ang II) and endothelin-1 (ET-1) share their effects on growth of myocardial cells but have been shown to elicit different effects on myocardial function. However, these effects vary markedly among species, cardiac regions (atrium or ventricle) and failing or non-failing myocardium. We therefore investigated the effects of both peptides on contractile function of isolated human myocytes from failing and non-failing hearts. METHODS AND RESULTS: Cardiomyocytes were enzymatically isolated and electrically stimulated (15 V, 0.2 Hz). Ang II elicited a positive inotropic effect (PIE) mediated by activation of protein kinase C (PKC) in atrial but no effect in ventricular myocytes. ET-1 (10(-8) M) increased cell-shortening by 146+/-9.3% (p<0.05) in atrial myocytes, by 99.1+/-16.5% (p<0.05) in non-failing ventricular but only by 40.5+/-6.4% (p<0.05) in failing ventricular myocytes. The PIE of ET-1 in failing myocytes was more pronounced at low extracellular pH (+112.6+/-27% at pH 7.0 vs. +40.5+/-6.4% at pH 7.4, p<0.05). Amiloride, a sodium-hydrogen-exchange inhibitor, inhibited two thirds of the PIE of ET-1 in failing myocytes. The PKC-inhibitor decreased the PIE by 50% from 113% to 64% in ventricular myocytes under acidotic conditions. CONCLUSION: Ang II and ET-1 elicited PIE in atrial myocytes, whereas in ventricular myocytes Ang II did not induce PIE in contrast to ET-1. The PIE of ET-1 was markedly attenuated in failing myocytes. Under acidotic conditions, the PIE of ET-1 was more pronounced in failing myocytes, indicating that ET-1 may activate signaling processes in failing myocytes, which are not activated in normal myocytes.


Assuntos
Angiotensina I/farmacologia , Endotelina-1/farmacologia , Contração Muscular/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Angiotensina I/fisiologia , Endotelina-1/fisiologia , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Contração Muscular/fisiologia , Miócitos Cardíacos/fisiologia
12.
Artigo em Inglês | MEDLINE | ID: mdl-16273409

RESUMO

Changes in reproductive state or the environment may affect the sensitivity of the hypothalamic-pituitary-andrenal (HPA) axis. However, little is known about the dynamics of the resulting corticosteroid stress response, in particular in tropical mammals. In this study, we address the modulation of corticosterone release in response to different reproductive conditions and seasonality in 326 free-living common fruit-eating bats (Artibeus jamaicensis) on Barro Colorado Island in Panama during dry and wet seasons. We present strong evidence that stress sensitivity is primarily modulated by reproductive condition. In reproductively active females, corticosterone increases were more rapid and reached higher levels, but also decreased significantly faster than in inactive females. The corticosterone response was weaker in reproducing males than in females and delayed compared to non-reproductive males. Testes volume in reproductively active males was negatively correlated with corticosterone concentrations. Our findings suggest differentiated dynamics in the corticosterone stress response between sexes, potentially reflecting conflicting ecological demands. In females, a strong acute corticosterone response may represent high stress- and risk-sensitivity that facilitates escape and thus helps to protect reproduction. In males, suppression during reproductive activity could reflect lowered stress sensitivity to avoid chronically elevated corticosterone levels in times of frequent aggressive and therefore costly inter-male encounters.


Assuntos
Quirópteros/fisiologia , Corticosterona/sangue , Reprodução , Animais , Quirópteros/sangue , Meio Ambiente , Feminino , Glucocorticoides/sangue , Sistema Hipotálamo-Hipofisário/fisiologia , Masculino , Panamá , Sistema Hipófise-Suprarrenal/fisiologia , Radioimunoensaio , Estações do Ano , Caracteres Sexuais , Estresse Fisiológico , Testículo/anatomia & histologia
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