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EUV and soft X-ray-induced photofragmentation of the halothane (CF3CHBrCl) molecule has been investigated using time-of-flight mass spectrometry in the coincidence mode (PEPICO) covering the valence region and vicinity of the bromine 3d, chlorine 2p, and carbon 1s edges. Total and partial ion yields have been recorded as a function of photon energy. At lower photon energies, the heavier singly charged molecular fragments predominate in the mass spectra. On the other hand, there is a strong tendency to the atomization of the molecule at higher photon energies. Despite the different chemical environments experienced by the two carbon atoms, weak site-specific fragmentation is observed. In addition, ab initio quantum mechanical calculations at the MP2 level and a series of computations with multiconfigurational self-consistent field have been performed to describe the inner-shell states.
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The present study aims to establish the morphological, morphometric, and immunostaining patterns of the steroidogenic enzymes 17ß-HSD and 5α-reductase and androgen receptors (AR) during the prenatal development of the male gonad and epididymis of Cavia porcellus. Fetuses at 22, 25, 30, 40, 45, 50, and 60 days of gestation (DG) were used. Specimens were dissected and subjected to macroscopic, histological, histomorphometric, and immunohistochemical analyses. Genital and scrotal protrusions were identified in 22 DG embryos. Gonocytes were identified at 25 DG and the formation of primary testicular cords was observed at 30 DG. Through anatomical evaluation, we observed differentiation of the epididymis into the head, body, and tail at 45 DG. During development, there is a progressive decrease in the diameters of the testicular cords and epididymal ducts. 17ß-HSD enzyme immunostaining was observed in Leydig cells at all ages, while 5α-reductase was observed in Leydig cell cytoplasm and gonocytes at 40, 50, and 60 DG. AR shows gonocyte labeling at 30 DG. Thus, from the second trimester of pregnancy, it is possible to observe patterns of anatomical development, such as genital and scrotal prominence (22 DG), the appearance of gonocytes in the testicular cords at 25 DG, and the beginning of the organization of primary testicular cords at 30 DG, suggesting sexual differentiation. The 17ß-HSD, 5α-reductase, and ARs play an essential role in sexual development and differentiation, presenting immunostaining at different reproductive process times.
Assuntos
Epididimo , Testículo , Gravidez , Feminino , Cobaias , Masculino , Animais , Células Intersticiais do Testículo , Oxirredutases , Receptores AndrogênicosRESUMO
This study investigates the impact of eugenol (EU) supplementation on bovine oocyte in vitro maturation (IVM) and antioxidant capacity, as well as in vitro embryo production and quality after conventional in vitro fertilization (IVF). A total of 1077 cumulus oocyte complexes were cultured in TCM-199+ without EU supplementation (control treatment) or supplemented with EU at the concentrations of 10 µM (EU-10), 20 µM (EU-20), or 40 µM (EU-40). After IVM, the oocytes were subjected to IVF and embryo culture. The addition of EU at 40 µM to the IVM medium improved (P < 0.05) the antioxidant capacity and cleavage rate when compared to the control treatment. Moreover, a positive correlation (r = 0.61, P < 0.03) was observed between cleavage rate and EU concentration. The addition of EU at concentrations of 10 and 20 µM decreased (P < 0.05) the calreticulin (CALR) levels in expanded blastocysts when compared to the control treatment and EU-40 treatment. However, the EU-10 and EU-20 treatments had a greater (P < 0.05) mean total cell number (TCN) per expanded blastocyst when compared to the control treatment and EU-40 treatment. In conclusion, the addition of EU to the enriched culture medium during IVM of bovine oocytes improved the antioxidant capacity of the spent medium, as well as the cleavage rate and embryonic quality (i.e., TCN/expanded blastocyst), and reduced the endoplasmic reticulum stress (i.e., CALR levels) in the embryos. Thus, we recommend enriching the IVM medium with 10 µM EU for in vitro bovine embryo production.
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Eugenol , Técnicas de Maturação in Vitro de Oócitos , Animais , Antioxidantes/farmacologia , Blastocisto , Calreticulina , Bovinos , Contagem de Células/veterinária , Técnicas de Maturação in Vitro de Oócitos/veterináriaRESUMO
Objectives: The mechanism behind the progression of Mild Cognitive Impairment (MCI) to Alzheimer's disease (AD) remains poorly understood. However some evidence pointed out that the co-occurrence of metabolic conditions affecting glucose homeostasis, as type 2 diabetes mellitus (T2DM), may be an important catalyst in this context. Notably, candidate drugs which modulate common pathways in the development of MCI-to-AD mediated by T2DM may offer likely therapy for AD. Nonetheless, limited pharmacological alternatives that modulate common pathways in T2DM, MCI, and AD are available. In the recent decades, studies have shown that resveratrol may act as a neuroprotective compound, but little is known about its potential in improving cognitive and metabolic aspects associated with AD progression mediated by the co-association between TDM2-MCI.Methods: In this review, we discuss possible protective mechanisms of resveratrol on shared pathways associated with AD progression mediated by T2DM-MCI co-occurrence.Results: Some studies indicated that insulin resistance and hyperglycemia may be also a T2DM risk factor for the progression of MCI-to-AD, promoting alterations in metabolic pathways associated with neuronal plasticity, and increasing pro-inflammatory environment. Interestingly, basic research and clinical trials indicate that resveratrol may modulate those pathways, showing a potential neuroprotective effect of this polyphenol.Conclusion: Therefore, there is not enough clinical data supporting the translational therapeutic use of resveratrol in this scenario.
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Doença de Alzheimer , Disfunção Cognitiva , Diabetes Mellitus Tipo 2 , Doenças Neurodegenerativas , Humanos , Resveratrol/uso terapêutico , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/prevenção & controle , Doença de Alzheimer/complicações , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/complicaçõesRESUMO
The social and economic roles of goat farming in Northeastern Brazil, allied to the fact that the use of goat middle ear ossicles for research and human ear surgery training has not yet been proposed, justify the study of their applicability as an experimental model. The middle ears of 19 goats (Capra aegagrus hircus) from the bone collection of the Laboratory and Didactic Anatomy Museum of Domestic and Wild Animals of the Federal University of Vale do São Francisco (UNIVASF) were dissected. The malleus, incus, and stapes were evaluated regarding their macroscopic morphology and biometry (length, width, and height). Ossicle morphology was similar to sheep, human, and bovine morphology. The malleus was 1.3 times heavier and 2.2 times longer than the incus, and 9.0 times heavier and 3.7 times longer than the stapes. The size relationship was positive between the stapes and the malleus and negative between the stapes and the incus. It is concluded that the middle ear size and the anatomical similarities with human ossicles make goats a useful model for experimental scientific studies, reconstructive surgery practice of the ossicular chain, and human ear surgery training.(AU)
Tanto o papel social quanto o econômico da caprinocultura na região Nordeste do Brasil, somados ao fato de que o uso de ossículos da orelha média de caprinos para estudos e treinamento cirúrgico otológico humano ainda não foi proposto, justificam o estudo de sua aplicabilidade como modelo experimental. Foram dissecadas as orelhas médias de 19 caprinos (Capra aegagrus hircus), provenientes do ossuário do Laboratório e Museu Didático de Anatomia dos Animais Domésticos e Silvestres - Universidade Federal do Vale do São Francisco. Martelos, bigornas e estribos tiveram a morfologia macroscópica e a biometria (comprimento, largura e altura) avaliadas. A morfologia dos ossículos assemelhou-se a de ovinos, humanos e bovinos. O martelo foi 1,3 vez mais pesado e 2,2 vezes mais comprido que a bigorna e 9,0 vezes mais pesado e 3,7 vezes mais comprido que o estribo. A relação de tamanho entre o estribo e o martelo foi positiva, e entre o estribo e a bigorna negativa. Conclui-se que o tamanho da orelha média e as semelhanças anatômicas com os ossículos humanos tornam os caprinos um modelo útil para estudos científicos experimentais, prática cirúrgica reconstrutiva da cadeia ossicular e treinamento cirúrgico otológico humano.(AU)
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Animais , Estribo/anatomia & histologia , Cabras/anatomia & histologia , Ossículos da Orelha/anatomia & histologia , Bigorna/anatomia & histologia , Martelo/anatomia & histologia , Biometria , Modelos AnimaisRESUMO
Talinum paniculatum (Jacq.) Gaertn. (Talinaceae), popularly known as "major gomes," is a Brazilian Cerrado plant used in traditional medicine and as a food source. Recent studies have demonstrated its diuretic effects. However, no studies have been performed on its effects on the reproductive system. Therefore, we aimed to investigate the effects of the ethanol-soluble fraction of T. paniculatum leaves (ESTP) on general toxicity and on the pubertal development of male and female Wistar rats. For this purpose, the uterotrophic and the pubertal assays were performed. In the uterotrophic test, female immature rats were treated for three consecutive days with 30, 100, or 300 mg/kg of ESTP. Uterus without luminal fluid was weighed and the relative weight calculated. For the pubertal assay, male and female immature rats were submitted to 30-day treatment with 30 or 300 mg/kg of ESTP. Clinical signs of toxicity, biochemical, and histopathological parameters were evaluated. ESTP treatment did not promote estrogenic effects in female rats. In the pubertal test, no daily signs of toxicity or weight loss were observed. Moreover, ESTP did not affect the onset of vaginal opening and preputial separation and did not cause significant changes in biochemical parameters as well as in organ weight and histopathological analyses of animals.
Assuntos
Caryophyllales , Extratos Vegetais/toxicidade , Maturidade Sexual/efeitos dos fármacos , Animais , Bioensaio , Brasil , Estrogênios , Feminino , Masculino , Tamanho do Órgão , Ratos , Ratos Wistar , ÚteroRESUMO
Brazilian poultry production is growing, mainly due to the cost and benefit that chicken meat provides. The importance of free-range chickens and the susceptibility, to which they are exposed, makes it necessary to know about gastrointestinal parasites and the consequences that large infections can cause for them as such as weight loss. The present study aimed to determine the occurrence of gastrointestinal parasites in free-range hens raised in an extensive regime in the municipality of Santa Rita, state of Maranhão, Brazil. The studied population was composed of adult chickens (Gallus gallus domesticus) acquired from slaughterhouses in the region. The gastrointestinal organs of each chicken were separated and subsequently conditioned in flasks containing Railliet and Henrys solution and sent to the laboratory, to be analyzed and processed. Of the 100 chickens examined, 227 specimens of helminthes were identified, with a frequency of 32.6% for nematodes and 67.4% for cestodes. Among the nematode the following parasites were identified: Ascaridia galli (27.03%); Heterakis gallinarum (48.65%) and Subulura spp. (24, 32%). Raillietina echinobothrida (100%) was the only cestoda identified. The average infection rate by species of parasite was 1.18 for A. galli, 2.22 for H. gallinarum, 1.06 for Subulura spp. and 9.00 for R. echinobothrida. It is concluded that free-range chickens are parasitized by nematodes and cestoda.
Assuntos
Animais , Galinhas/anatomia & histologia , Galinhas/parasitologia , Trato Gastrointestinal/parasitologiaRESUMO
Brazilian poultry production is growing, mainly due to the cost and benefit that chicken meat provides. The importance of free-range chickens and the susceptibility, to which they are exposed, makes it necessary to know about gastrointestinal parasites and the consequences that large infections can cause for them as such as weight loss. The present study aimed to determine the occurrence of gastrointestinal parasites in free-range hens raised in an extensive regime in the municipality of Santa Rita, state of Maranhão, Brazil. The studied population was composed of adult chickens (Gallus gallus domesticus) acquired from slaughterhouses in the region. The gastrointestinal organs of each chicken were separated and subsequently conditioned in flasks containing Railliet and Henrys solution and sent to the laboratory, to be analyzed and processed. Of the 100 chickens examined, 227 specimens of helminthes were identified, with a frequency of 32.6% for nematodes and 67.4% for cestodes. Among the nematode the following parasites were identified: Ascaridia galli (27.03%); Heterakis gallinarum (48.65%) and Subulura spp. (24, 32%). Raillietina echinobothrida (100%) was the only cestoda identified. The average infection rate by species of parasite was 1.18 for A. galli, 2.22 for H. gallinarum, 1.06 for Subulura spp. and 9.00 for R. echinobothrida. It is concluded that free-range chickens are parasitized by nematodes and cestoda.(AU)
Assuntos
Animais , Trato Gastrointestinal/parasitologia , Galinhas/anatomia & histologia , Galinhas/parasitologiaRESUMO
The ratios of single, double, and triple ionizations to the total photoionization of the halothane (C2HBrClF3) molecule have been investigated by a single-photon ionization in the energy range from 21.21 eV to 320 eV. In the valence region, the multiple ionization results can be described by a sum of contributions generated from the shake-off and the two-step one models. At low photon energies (from the threshold of triple ionization up to 100 eV), the triple photoionization dynamics of halothane can be reasonably well described by a model involving a classical electron impact double ionization of the singly ionized parent ion.
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Este trabalho investigou a influência da adiposidade em éguas Crioulas gestantes sobre o peso e o acúmulo de gordura de seus potros do nascimento aos quatro meses de vida. Foram avaliadas 28 éguas Crioulas no terço final de gestação, divididas em dois grupos (normais e obesas) quanto ao peso, à circunferência de pescoço, à altura da crista do pescoço e à gordura subcutânea na base da cauda, bem como quanto à relação dessas medidas com as de seus potros, do parto aos 120 dias de idade. Os filhos de éguas obesas apresentaram maior deposição de gordura na base da cauda, no segundo mês (P<0,05), e na crista do pescoço (P=0,0022), no quarto mês de idade. Houve correlação positiva da altura da crista do pescoço da égua com o peso dos potros ao nascer (P=0,01; r= 0,54) e do peso corporal das éguas com gordura na base da cauda dos potros ao nascimento (P=0,03; r=0,49), além de forte associação entre gordura na base da cauda das éguas obesas com essa medida nos seus potros aos quatro meses (P=0,01; r=0,71). Essa diferença entre os grupos de potros quanto à adiposidade sugere que filhos de éguas obesas são mais propensos a acumular mais gordura já nos primeiros meses de vida.(AU)
This work investigated the influence of adiposity on pregnant Crioulo mares on the weight and fat deposition of their foals from birth to four months of life. Twenty-eight Crioulo mares were evaluated during the final third of gestation, divided into two groups (normal and obese) regarding weight, neck circumference, neck crest height and fat at the tail base, and the relation of these measurements with those of their foals from birth to 120 days old. The obese mares presented higher fat deposition at the tail base in the 2nd month (P< 0.05) and crest of the neck (P= 0.0022) in the 4th month of age. There was positive correlation between height of mare's neck crest and foal weight at birth (P= 0.01, r= 0.54) and body weight of mares between the fat at tail base of foals at birth (P= 0.03, r= 0.49), as well as strong association between fat at the tail base in obese mares with this measurement in their foals at 4 months (P= 0.01, r= 0.71). This difference of adiposity between groups suggests that obese mare's offspring are more likely to accumulate more fat in the first months of life.(AU)
Assuntos
Animais , Feminino , Gravidez , Peso Corporal , Pesos e Medidas Corporais/veterinária , Gordura Subcutânea , Cavalos/anatomia & histologia , Animais Recém-Nascidos/anatomia & histologia , Tecido Adiposo , Hereditariedade , Obesidade Materna/genéticaRESUMO
Este trabalho investigou a influência da adiposidade em éguas Crioulas gestantes sobre o peso e o acúmulo de gordura de seus potros do nascimento aos quatro meses de vida. Foram avaliadas 28 éguas Crioulas no terço final de gestação, divididas em dois grupos (normais e obesas) quanto ao peso, à circunferência de pescoço, à altura da crista do pescoço e à gordura subcutânea na base da cauda, bem como quanto à relação dessas medidas com as de seus potros, do parto aos 120 dias de idade. Os filhos de éguas obesas apresentaram maior deposição de gordura na base da cauda, no segundo mês (P<0,05), e na crista do pescoço (P=0,0022), no quarto mês de idade. Houve correlação positiva da altura da crista do pescoço da égua com o peso dos potros ao nascer (P=0,01; r= 0,54) e do peso corporal das éguas com gordura na base da cauda dos potros ao nascimento (P=0,03; r=0,49), além de forte associação entre gordura na base da cauda das éguas obesas com essa medida nos seus potros aos quatro meses (P=0,01; r=0,71). Essa diferença entre os grupos de potros quanto à adiposidade sugere que filhos de éguas obesas são mais propensos a acumular mais gordura já nos primeiros meses de vida.(AU)
This work investigated the influence of adiposity on pregnant Crioulo mares on the weight and fat deposition of their foals from birth to four months of life. Twenty-eight Crioulo mares were evaluated during the final third of gestation, divided into two groups (normal and obese) regarding weight, neck circumference, neck crest height and fat at the tail base, and the relation of these measurements with those of their foals from birth to 120 days old. The obese mares presented higher fat deposition at the tail base in the 2nd month (P< 0.05) and crest of the neck (P= 0.0022) in the 4th month of age. There was positive correlation between height of mare's neck crest and foal weight at birth (P= 0.01, r= 0.54) and body weight of mares between the fat at tail base of foals at birth (P= 0.03, r= 0.49), as well as strong association between fat at the tail base in obese mares with this measurement in their foals at 4 months (P= 0.01, r= 0.71). This difference of adiposity between groups suggests that obese mare's offspring are more likely to accumulate more fat in the first months of life.(AU)
Assuntos
Animais , Feminino , Gravidez , Peso Corporal , Pesos e Medidas Corporais/veterinária , Gordura Subcutânea , Cavalos/anatomia & histologia , Animais Recém-Nascidos/anatomia & histologia , Tecido Adiposo , Hereditariedade , Obesidade Materna/genéticaRESUMO
BACKGROUND: The purpose of this experimental study was to compare the immunohistochemical expression of SOX2 and BCL-2 in Odontogenic Keratocyst (OKC) and Ameloblastoma (AB) specimens, and to identify a possible correlation in their expression. MATERIAL AND METHODS: Immunohistochemical analysis was performed to evaluate SOX2 and BCL-2 expression in OKC (n = 20) and AB (n = 20). The immunoexpression was analyzed by a quantitative and qualitative scoring system. The comparison between the immunoexpression of SOX 2 and BCL-2 was assessed by the Mann-Whitney U-test. Spearman's correlation coefficient evaluated the correlation between SOX2 and BCL-2 expressions. RESULTS: SOX2 and BCL-2 expression was observed in all specimens of OKC in the full thickness of the epithelium lining. SOX2 immunostaining was higher in OKC, in comparison with AB samples (P<0.05). BCL-2 immunostaining between OKC and AB was not statistically significant. There was no significant correlation between SOX2 and BCL-2 in OKC and AB specimens. CONCLUSIONS: SOX2 and BCL-2 expressions in OKC may suggest their relationship with the biological behavior of this lesion, and the higher expression of SOX2 might be an upstream influence on the Hh signaling pathway.
Assuntos
Ameloblastoma , Cistos Odontogênicos , Tumores Odontogênicos , Humanos , Proteínas Proto-Oncogênicas c-bcl-2 , Fatores de Transcrição SOXB1RESUMO
Chronic cocaine use has been shown to lead to neurotoxicity in rodents and humans, being associated with high morbidity and mortality rates. However, recreational use, which may lead to addictive behavior, is often neglected. This occurs, in part, due to the belief that exposure to low doses of cocaine comes with no brain damage risk. Cocaine addicts have shown glucose metabolism changes related to dopamine brain activity and reduced volume of striatal gray matter. This work aims to evaluate the morphological brain changes underlying metabolic and locomotor behavioral outcome, in response to a single low dose of cocaine in a pre-clinical study. In this context, a Balb-c mouse model has been chosen, and animals were injected with a single dose of cocaine (0.5 mg/kg). Control animals were injected with saline. A behavioral test, positron emission tomography (PET) imaging, and anatomopathological studies were conducted with this low dose of cocaine, to study functional, metabolic, and morphological brain changes, respectively. Animals exposed to this cocaine dose showed similar open field activity and brain metabolic activity as compared with controls. However, histological analysis showed alterations in the prefrontal cortex and hippocampus of mice exposed to cocaine. For the first time, it has been demonstrated that a single low dose of cocaine, which can cause no locomotor behavioral and brain metabolic changes, can induce structural damage. These brain changes must always be considered regardless of the dosage used. It is essential to alert the population even against the consumption of low doses of cocaine.
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We determined depth profiles of total mercury (T-Hg) in six 210Pb-dated sediment cores from Todos os Santos Bay to reconstruct the history of anthropogenic Hg accumulation. We also assessed superficial sediments samples from five estuaries. T-Hg concentrations (5-3500⯵gâ¯kg-1) presented a large spatial and temporal variability. T-Hg concentrations in Ribeira Bay increased up to 200-fold along time, whereas the fluxes of T-Hg are substantially higher (up to 10,000 fold) than present-day wet deposition for industrialized areas. Sedimentary records indicate that a chlor-alkali plant has been the main source of Hg pollution until the present, although the T-Hg records suggest that harbor, shrimp farming, and oil refinery activities, besides Hg atmospheric depositions, are important across the bay. Sediments in the Ribeira Bay act as an important Hg sink. If sediments are eroded or disturbed, they may release Hg, thus posing a serious risk to wildlife and ecosystem health. CAPSULE: Sedimentary cores provide data on preindustrial levels and also anthropogenic fluxes of Hg for the appraisal of the magnitude, processes and potential risks of the contamination.
Assuntos
Sedimentos Geológicos , Atividades Humanas/história , Mercúrio/análise , Poluentes Químicos da Água/história , Baías , Brasil , Ecossistema , Monitoramento Ambiental , Poluição Ambiental/história , História do Século XX , História do Século XXI , Humanos , Poluentes Químicos da Água/análiseRESUMO
We have performed an experimental investigation into the interaction of vacuum-ultraviolet synchrotron radiation with pyridine molecules in the gas phase. Specifically, a double-ion chamber spectrometer was used to measure the absolute photoabsorption cross sections and the photoionization quantum yields from the ionization threshold to 21.5 eV. Moreover, photoionization and neutral-decay cross sections in absolute scale were derived from these data. In addition, the fragmentation pattern was investigated as a function of the photon energy by using a time-of-flight mass spectrometer and the photoelectron-photoion coincidence technique. Thus, the absolute partial ionization cross sections for each ionic fragment were obtained. Comparisons are made with experimental data available in the literature.
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Abstract The distribution of most species occurs in delimited regions with unique characteristics called "centers of endemism". In Eastern Amazon is located the Belém Endemism Center (BEC), one of the most intensely deforested in Brazilian Amazon. Here, we show information about orchid bee assemblages based on historical records from entomological collections. For each species, we calculated occurrence frequency and dominance, and we classified them in 3 statuses: common, intermediate or rare species. Curves of observed and estimated richness were built, based on Jackknife estimator. We found 1,257 specimens from 56 species, constituting records from 1917 to 2009, and one species is a new record for BEC. Higher number of specimens and species was concentrated in a few locations and surveys increased from the 70's. The results suggest a high richness of orchid bees in the BEC, although this scenario is far from what is expected for the entire area. The high occurrence of rare species may be related to their low representativeness in the collections, and the proximity between the areas had favored samplings. Even so, the species list and the conservation status presented here may be useful information in studies comparing past and current orchid bee fauna, and, allied to data on bees' responses to land use changes occurred in BEC over the years, can fit as a basis for defining priority areas for conservation.
Resumo A distribuição da maioria das espécies ocorre em regiões delimitadas com características únicas conhecidas como "centros de endemismo". Na Amazônia Oriental está localizado o Centro de Endemismo Belém (CEB), uma das áreas mais intensivamente desmatadas na Amazônia Brasileira. Aqui, apresentamos informações sobre assembleias de abelhas orquídeas baseadas em registros históricos de coleções entomológicas. Para cada espécie, foram calculadas a frequência de ocorrência e a dominância, classificando-as em 3 estados: espécies comuns, intermediárias ou raras. Foram geradas curvas de riqueza observada e estimada, com base no estimador Jackknife. Encontramos 1.257 espécimes de 56 espécies, constituindo registros de 1917 a 2009, e uma espécie é um novo registro no CEB. Maior número de espécimes e espécies foi concentrado em poucos locais, com intensificação nas coletas a partir dos anos70. Os resultados sugerem alta riqueza de abelhas orquídeas no CEB, embora esse cenário esteja longe do que é esperado para toda a área. A elevada ocorrência de espécies raras pode estar relacionada à baixa representatividade nas coleções e a proximidade entre as áreas favoreceu as amostragens. Mesmo assim, a lista de espécies e o estado de conservação aqui apresentados podem ser informações úteis em estudos interessados em comparar a fauna passada e atual de abelhas das orquídeas e, aliado a dados sobre as respostas das abelhas às mudanças de uso da terra ocorridas no CEB ao longo dos anos, podem servir de base para definição de áreas prioritárias para conservação.
Assuntos
Animais , História do Século XX , História do Século XXI , Abelhas/classificação , Abelhas/fisiologia , Brasil , Espécies em Perigo de Extinção , Conservação dos Recursos NaturaisRESUMO
OBJECTIVE: The present study aimed to evaluate and clarify how the age at which the intake of a high-fat and high-fructose diet begins can affect animals' livers. METHODS: Thirty-eight male wistar rats aged 6 and 12 weeks were fed a high-fat and high-fructose diet for 13 weeks. Inflammatory cytokines, hepatic glycogen, serum and hepatic triacylglycerol and pAkt protein content in the liver were assessed. Percentage of weight gained, and visceral adiposity were also evaluated. RESULTS: Young animal presented increased hepatic triacylglycerol and decreased glycogen, while adult animals had no significant alterations regarding its contents. IL6 and IL10 to IL6 ratio were also altered in young animals exposed to HFHF, while adult animals fed with HFHF had only increases in TNF-α. Both groups which received HFHF had increased serum triacylglycerol and visceral adiposity. However, only young animals gained more relative weight and had greater final body weight, gains which were related to alterations found in hepatic triacylglycerol and glycogen. CONCLUSION: Age of which consumption begins interferes in how the liver deals with an excess of nutrient and subsequent proinflammatory stimulation, leading to different phenotypes.
Assuntos
Envelhecimento/metabolismo , Dieta Hiperlipídica , Açúcares da Dieta/administração & dosagem , Frutose/administração & dosagem , Fígado/metabolismo , Animais , Citocinas/metabolismo , Glicogênio/metabolismo , Masculino , Ratos Wistar , Triglicerídeos/metabolismoRESUMO
Nasutitermes corniger (Motschulsky, 1855) (Termitidae: Nasutitermitinae) is an important pest in urban environments and bioinsecticides can be an alternative to its control. Here, we determined the toxicity and repellence of the essential oil (EO) prepared from stems of Aristolochia trilobata L. (Aristolochiaceae) and its major constituents on N. corniger. We also investigated behavioral changes of individuals exposed to limonene. The lethal dose required to kill 50% of N. corniger population (LD50) of EO of A. trilobata was 2.44 µg mg-1. Limonene was the most toxic compound to N. corniger followed by linalool (LD50 = 1.02 and 1.29 µg mg-1, respectively). In addition, all treatments presented median lethal time (LT50) less than 11 h. A. trilobata EO and its constituents showed irritability activity, but only limonene repelled soldiers more than workers. The negative behaviors of N. corniger groups were higher in individuals treated with limonene. A. trilobata EO and its constituents, especially the limonene, are promising for the control of N. corniger due the high toxicity, repellence, and possible disturbance in the colonies.
Assuntos
Aristolochia/química , Inseticidas , Isópteros , Óleos Voláteis , Monoterpenos Acíclicos , Animais , Repelentes de Insetos , Limoneno , Monoterpenos , Óleos de Plantas , Testes de Toxicidade AgudaRESUMO
The distribution of most species occurs in delimited regions with unique characteristics called "centers of endemism". In Eastern Amazon is located the Belém Endemism Center (BEC), one of the most intensely deforested in Brazilian Amazon. Here, we show information about orchid bee assemblages based on historical records from entomological collections. For each species, we calculated occurrence frequency and dominance, and we classified them in 3 statuses: common, intermediate or rare species. Curves of observed and estimated richness were built, based on Jackknife estimator. We found 1,257 specimens from 56 species, constituting records from 1917 to 2009, and one species is a new record for BEC. Higher number of specimens and species was concentrated in a few locations and surveys increased from the 70's. The results suggest a high richness of orchid bees in the BEC, although this scenario is far from what is expected for the entire area. The high occurrence of rare species may be related to their low representativeness in the collections, and the proximity between the areas had favored samplings. Even so, the species list and the conservation status presented here may be useful information in studies comparing past and current orchid bee fauna, and, allied to data on bees' responses to land use changes occurred in BEC over the years, can fit as a basis for defining priority areas for conservation.