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In this survey, we investigated the diversity and community structure of bats in the Centre Region of Cameroon with respect to their distribution in the different vegetation zones of the region. We mist-netted bats monthly from January 2016 to June 2017 for five nonconsecutive nights per month. Thirty-nine sites were surveyed: 24 in traditional farms, nine in the savannah and six in the forests. A total of 668 bats were captured during 81 nights of capture, covering seven families, 21 genera and 36 species. This included 26 species in traditional farms, 13 species in savannah and 11 species in the forest. Micropteropus pusillus was the most abundant species (30.7%) recorded, followed by Hipposideros ruber (24.9%). The sample efficiency was estimated at 72.1% with fitted species accumulation curves not reaching asymptotes for the three habitat types, suggesting that the survey did not record all the bats present. There was an indication of general increased in abundance of bats during the dry and rainy seasons but it is not significant (Mann–Whitney U: 783.5, p = .195). The rarity index was highest in traditional farms (0.44), followed by savannah (0.38) and then forest (0.33). This preliminary survey provides baseline data on the distribution of bats in the different vegetation types in the Centre Region of Cameroon.  相似文献   
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Summary Atrial natriuretic factor (ANF) is a cardiac hormone with various functions in body homeostasis. It is also processed in the brain and in the peripheral nervous system where it appears to play a role as a neuromodulator. Little is known about the presence of ANF throughout the spinal cord of the guinea-pig. We therefore examined the distribution of ANF and its possible interrelation with primary sensory afferents in this species. Using enzyme- and fluorescence-immunohistochemistry on deparaffinized sections, ANF-like immunoreactivity was found to be present in nerve fibers in laminae I/II of the spinal cord and in neurons of spinal and trigeminal ganglia. Tachykinins and ANF coexisted in very few fibers of the spinal cord but did not coexist in primary sensory spinal or trigeminal neurons. Our results indicate that spinal ANF-immunoreactive fibers are of dual origin, primary sensory and non-primary sensory. The possibly heterogeneous source of the non-primary sensory ANF, its possible coexistence with other co-transmitters and functional implications are discussed.Preliminary aspects of this study have been reported at the 2nd World Congress of Neuroscience in Budapest (Weihe et al. 1987) and at the Versammlung der Anatomischen Gesellschaft in Zürich (Nohr et al. 1989)  相似文献   
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BackgroundThe purpose of this study is to estimate and project the number of years of potential life lost (YPLL) among males who die of prostate cancer in the United States from 2004 through 2050 and compare the projections by race/ethnicity and age, accounting for demographic changes and population growth.MethodsWe applied the life expectancy method to estimate YPLL caused by deaths of prostate cancer and all cancers in men by using 1999–2004 national mortality data, 2008 census population demographic projections, and 2004 U.S. life tables. We performed sensitivity analyses by varying death rate and population projections, and examined increase in YPLL from population growth, changes in demographics, and death rates.ResultsThe number of YPLL caused by prostate cancer deaths was projected to increase by 226.1%, from 291,853 in 2004 to 951,753 in 2050. Hispanics were projected to have the fastest growth in YPLL (977.1% from 2004 to 2050) caused by prostate cancer, followed by non-Hispanic blacks (543.1%), and non-Hispanic others (269.7%). People aged 75 or older was projected to account for 62.0% of YPLL from prostate cancer in 2050 compared with 50.8% in 2004. Of the projected increase in YPLL caused by prostate cancer deaths by 2050, 9.8% were due to changes in demographic composition, 26.8% because of mortality change, and 63.4% because of population growth.ConclusionsYPLL due to prostate cancer deaths are projected to increase dramatically, and become a greater burden in the future. The projections highlight the importance of comprehensive cancer control and research on cancers including prostate cancer and racial/ethnic-specific estimates.  相似文献   
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BackgroundEbola virus disease is a highly virulent and transmissible disease. The largest recorded fatality from Ebola virus disease epidemic is ongoing in a few countries in West Africa, and this poses a health risk to the entire population of the world because arresting the transmission has been challenging. Vaccination is considered a key intervention that is capable of arresting further spread of the disease and preventing future outbreak. However, no vaccine has yet been approved for public use, although various recombinant vaccines are undergoing trials and approval for public use is imminent. Therefore, this study aimed to determine the acceptability of and willingness-to-pay for Ebola virus vaccine by the public.MethodsThe study was a community-based cross-sectional qualitative and quantitative interventional study conducted in two communities, each in two states in Nigeria. An interviewer-administered questionnaire was used to collect information on respondents’ knowledge of the Ebola virus, the ways to prevent the disease, and their preventive practices, as well as their acceptability of and willingness-to-pay for a hypothetical vaccine against Ebola virus disease. The association between acceptability of the vaccine and other independent variables were evaluated using multivariate regression analysis.ResultsEbola virus disease was considered to be a very serious disease by 38.5% of the 582 respondents (224/582), prior to receiving health education on Ebola virus and its vaccine. Eighty percent (80%) accepted to be vaccinated with Ebola vaccine. However, among those that accepted to be vaccinated, most would only accept after observing the outcome on others who have received the vaccine. More than 87.5% was willing to pay for the vaccine, although 55.2% was of the opinion that the vaccine should be provided free of charge.ConclusionThe level of acceptability of Ebola virus vaccine among respondents was impressive (though conditional), as well as their willingness to pay for it if the vaccine is not publicly funded. In order to achieve a high uptake of the vaccine, information and education on the vaccine should be extensively shared with the public prior to the introduction of the vaccine, and the vaccine should be provided free of charge by government.  相似文献   
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Live attenuated Salmonella are attractive vaccine candidates for mucosal application because they induce both mucosal immune responses and systematic immune responses. After breaking the epithelium barrier, Salmonella typhimurium is found within dendritic cells (DC) in the Peyer's patches. Although there are abundant data on the interaction of S. typhimurium with murine epithelial cells, macrophages and DC, little is known about its interaction with human DC. Live attenuated S. typhimurium have recently been shown to efficiently infect human DC in vitro and induce production of cytokines. In this study, we have analysed the morphological consequences of infection of human DC by the attenuated S. typhimurium mutant strains designated PhoPc, AroA and SipB and the wild-type strains of the American Type Culture Collection (Manassas, VA, USA), ATCC 14028 and ATCC C53, by electron microscopy at 30 min, 3 h and 24 h after exposure. Our results show that genetic background of the strains profoundly influence DC morphology following infection. The changes included (i) membrane ruffling; (ii) formation of tight or spacious phagosomes; (iii) apoptosis; and (iv) spherical, pedunculated membrane-bound microvesicles that project from the plasma membrane. Despite the fact that membrane ruffling was much more pronounced with the two virulent strains, all mutants were taken up by the DC. The microvesicles were induced by all the attenuated strains, including SipB, which did not induce apoptosis in the host cell. These results suggest that Salmonella is internalized by human DC, inducing morphological changes in the DC that could explain immunogenicity of the attenuated strains.  相似文献   
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Background

Malnutrition is an underlying factor in more than 50% of the major cause of infant mortality-Pneumonia, diarrhoeal disease and measles which account for 70% of infant mortality. Therefore, programs to promote adequate nutrition for age can help reduce mortality from these disease conditions and indispensible to achievement of MDG 4.

Aim

To describe the feeding practices of infants below six months of age and determine maternal socio-demographic factors that influences the practice of exclusive breastfeeding (EBF) among mothers in Nnewi, south-east Nigeria.

Methods

Four hundred mother-infant pairs attending the infant welfare clinic of the Nnamdi Azikiwe University teaching hospital (NAUTH) during 2012 were consecutively recruited after meeting the study inclusion criteria. Data on breastfeeding were based on infant feeding practice in the previous 24 hours. Exclusive breastfeeding was defined as infant feeding with only breast milk.

Results

Awareness (95.3%) and knowledge (82.0%) of EBF was high among surveyed mother but the practice of EBF (33.5%) was very low. Positive attitude towards EBF practice was shown by many (71.0%) of surveyed mothers. EBF practice decreased with increasing infant age, OR 0.72 (95% CI 0.34, 1.51) for 1–2 months, OR 0.58 (95% CI 0.23, 1.44) for 3–4 months and OR 0.20 (95% CI 0.06, 0.73) for 5–6 months compared to infants?<?1 month old. Maternal education, socioeconomic class, mode of delivery and infants first feed were retained as important maternal predictors of EBF practice after adjustment for confounders. Decreased likelihood of EBF practice was found among mothers of lower educational attainment, OR 0.33 (95% CI 0.13, 0.81), mothers who delivered through caesarean section, OR 0.38 (95% CI 0.18, 0.84), mothers of higher socio-economic status [(middle class, OR 0.46 (95% CI 0.22, 0.99) and upper class, OR 0.32 (95% CI 0.14, 0.74)] while increased likelihood of EBF practice was seen in mothers who gave their infants breast milk as their first feed, OR 3.36 (95% CI 1.75, 6.66).

Conclusion

Knowledge and awareness does not translate to practice of EBF. More effort by health workers and policy makers should be directed to mothers along the fault lines to encourage the practice of EBF.
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Pyrgomorpha vignaudii (Guérin‐Méneville, 1849) is a pest of a wide variety of crop plants in Africa. To facilitate the search for a sustainable strategy against this pest, we have studied the post‐embryonic development, morphology and reproduction on Manihot esculenta in the laboratory. Five‐hundred and two larvae at the first stage of development obtained in the laboratory were individually reared in cages. Post‐embryonic development passed through seven stages. The total number of days spent for larval development varied from 77 to 108. The mean duration of development of stages 1, 2, 3, 4, 5 and 6 larvae were, respectively, 16.48 ± 0.43, 14.40 ± 0.55, 13.70 ± 0.61, 15.07 ± 0.84, 15.21 ± 1.31 and 16.21 ± 1.27 days. After the final molt, the females of P. vignaudii take an average of 12.7 ± 1.04 days before the first mating. The time between the first mating and first oviposition ranged from 14 to 34 days (averagely 25.2 ± 4.62 days). The females realized one to nine ovipositions during their lives. The number of eggs per egg‐pods (ootheca) varied from 16 to 93 with a mean of 45.31 ± 3.51. Our results provide valuable information for the search for a control strategy against P. vignaudii.  相似文献   
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The opioidergic innervation of the mammalian spleen and possible species differences were investigated. Light-microscopic immunohistochemistry revealed that splenic nerves of bovine and porcine spleen, but not of rat, mouse, hamster and guinea-pig spleen contained proenkephalin-derived opioidergic innervation. Immunoreactivity to both prodynorphin and pro-opiomelanocortin was absent from splenic nerves. In bovine and porcine spleen, fibers immunoreactive for met-enkephalin, met-enkephalin-Arg-Phe, met-enkephalin-Arg-Gly-Leu, leu-enkephalin and peptide F formed perivascular plexus, traveled in trabecular connective tissue, and extended into the capsule. Spatial relationships with immune cells were apparent in the white and red pulp, excluding lymphoid follicles. Colocalization of enkephalin immunoreactivity with immunoreactivities for tyrosin hydroxylase, dopamin--hydroxylase, and neuropeptide Y, but not for substance P or calcitonin gene-related peptide were found. Our results provide evidence that opioid expression in splenic innervation is strongly species-dependent and exclusively proenkephalin-derived. Colocalization with marker enzymes of noradrenergic neurons indicates a mainly postganglionic sympathetic origin of proenkephalinergic splenic innervation. Opioidergic perivascular nerves probably control the splenic blood flow. A close interrelationship of opioidergic fibers with immune cells provides the anatomical basis for direct effects of neurally released opioids on splenic immune functions.  相似文献   
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