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101.
Background: The present study was carried out in the rural and urban area of Diamantina/Minas Gerais (MG), an endemic municipality for visceral leishmaniasis (VL) in Brazil. Methods: Patient notification records, canine prevalence, and phlebotomine fauna were evaluated. Results: In the period from 2016 to 2018, eight human cases were confirmed, with three deaths, predominantly in males. In the same period, a total of 1,388 dogs resided in the rural and urban area of the municipality were submitted to the DPP® and ELISA, with a percentage of confirmed canine cases of 29.9% and 29.4%, respectively. The entomological study conducted in the municipality revealed the presence of 10 species of sand flies, with a predominance of Lutzomyia longipalpis (55.75%), mainly in the rural area. Conclusions: Unlike what is happening in urban centers, the results of this study suggest that the VL in Diamantina is in the process of urbanization, given the high percentage of confirmed canine cases and the high density of Lu. longipalpis in the rural area of the municipality. These risk factors warn about the need for continuous surveillance and the need to control actions of VL in this area.  相似文献   
102.
ABSTRACT. We describe the finding of unizoic cysts of Isospora helli in lymphoid tissues of a Brazilian patient with AIDS, and discuss the possibilities of their drug resistance, they being the cause of relapses, and of being an indication for the existence of intermediary or paratenic animal hosts.  相似文献   
103.
The eucalyptus woodborer, Phoracantha semipunctata Fabricius (Coleoptera: Cerambycidae), attacks mainly species of Eucalyptus (Myrtaceae). This study investigated walking and flight behaviour of P. semipunctata males and females exposed to an odour plume originating from a log of E. globulus placed vertically in the upwind end of a wind tunnel. In control experiments, beetles were exposed to a PVC drainpipe in the same position as the log, providing a visual stimulus without host‐tree odour. No statistical differences were found between behavioural responses of either sex when exposed to the log or PVC pipe. No beetles landed on the PVC pipe, whereas 49% of the beetles exposed to host‐tree odour plume landed on the log. Beetles aged over 24 days after emergence from the host tree were more responsive than beetles aged 20–24 days, and accounted vor 86% of the beetles that landed on the log. While walking, host‐tree odour affected the behaviour of the beetles that landed on the log as follows: upwind movement and path linearity increased, whereas turning rate, stopping frequency, mean stopping time and time to take‐off flight decreased. During flight, host‐tree odour affected the behaviour of the beetles that landed on the log as follows: increased upwind flight, turning rate, flight time, flight distance, and decreased flight speed. For beetles that never lost contact with the odour plume, flight progressed upwind with narrow zigzags, and showed higher directedness upwind, path linearity, faster flight speed and lower turning rate than for beetles that lost contact with the odour plume. After loosing contact with the plume, beetles tended to decrease their upwind progression, exhibiting a sharp turn or quick counterturns followed by crosswind or downwind excursions. This led to regaining contact with the odour plume and resumed upwind progression at higher speed provided they flew within the boundaries of the plume. The results showed that host‐tree odour affects both walking and flight behaviour of P. semipunctata beetles, inducing a more directed upwind movement and landing on the visual stimulus of a tree trunk.  相似文献   
104.
During April and May 2006, experiments were carried out in Brejo do Mutambal, Varzelandia Town, Minas Gerais State, to evaluate the attractiveness of phlebotomine sandflies to CDC light traps, baited with kairomones. Of the 19 species of Lutzomyia already registered for the region, L. lutziana (Costa Lima), L. longipennis (Barreto), L. goiana (Martins, Falc?o & Silva) and L. brasiliensis (Costa Lima) were recorded for the first time, thus increasing the diversity of phlebotomine sandflies fauna in this area to 23 species. The new registered species and distribution are shown and discussed herein.  相似文献   
105.
The objective of this study was to analyze the morphological and histological characteristics of eggs from six triatomine species in order to obtain a generic and specific characterization of this group of Trypanosoma cruzi vectors and better understand their phylogenetic and taxonomic aspects. The eggs of the respective species came from the collection of the Laboratório de Triatomíneos e Culicídeos da Faculdade de Saúde Pública/USP, from the Insetário do Servi?o Especial de Saúde de Araraquara - SESA and from the Triatomine insectary of the Laboratório Nacional e Internacional de Referência em Taxonomia de Triatomíneos (FIOCRUZ), in Rio de Janeiro. Morphological studies were done with optical microscopy and scanning electron microscopy. Histological analyses used only optical microscopy. All of the species analyzed showed a predominance of hexagonal cells. The exchorion of Triatoma breyeri Del Ponte, T. costalimai Verano Galv?o, and T. tibiamaculata (Pinto) consists of unornamented cells, overlapping or slightly separated, with a smooth, padded appearance. Meanwhile, in T. matogrossensis Leite Barbosa, T. sherlocki Papa, Juberg, Carcavallo, Cerqueira Barata, and T. williami Galv?o, Souza Lima, the exchorion cells are ornamented on their entire surface with perforations and fissures. Egg histology showed undulations, pores, and orifices. The study helps to expand the generic and specific knowledge of the Triatominae subfamily. The characteristics identified in the exchorion of the eggshells can help separate close species. These new parameters will back the elaboration of future dichotomous keys, help to determine each vector species role and expand knowledge of the various species.  相似文献   
106.

Objectives

The current study aimed at describing the distribution and characteristics of malignancy related deaths in human immunodeficiency virus (HIV) infected patients in 2010 and at comparing them to those obtained in 2000 and 2005.

Methods

Data were obtained from three national surveys conducted in France in 2010, 2005 and 2000. The underlying cause of death was documented using a standardized questionnaire fulfilled in French hospital wards involved in the management of HIV infection.

Results

Among the 728 deaths reported in 2010, 262 were cancer-related (36%). After a significant increase from 28% in 2000 to 33% in 2005 and 36% in 2010, cancers represent the leading cause of mortality in HIV infected patients. The proportion of deaths attributed to non-AIDS/non-hepatitis-related cancers significantly increased from 2000 to 2010 (11% of the deaths in 2000, 17% in 2005 and 22% in 2010, p<0.001), while those attributed to AIDS-defining cancers decreased during the same period (16% in 2000, 13% in 2005 and 9% in 2010, p = 0.024). Particularly, the proportion of respiratory cancers significantly increased from 5% in 2000 to 6% in 2005 and 11% in 2010 (p = 0.004). Lung cancer was the most common cancer-related cause of death in 2010 (instead of non-Hodgkin lymphoma so far) and represented the leading cause of death in people living with HIV overall.

Conclusions

Cancer prevention (especially smoking cessation), screening strategies and therapeutic management need to be optimized in HIV-infected patients in order to reduce mortality, particularly in the field of respiratory cancers.  相似文献   
107.
The current study shows cytological differences between the anal glands of pre‐spawning and spawning peacock blennies Salaria pavo. The cytological differences in the anal gland coincide with higher olfactory potency of their secretions in spawning males, suggesting that seasonal differentiation of cell clusters secreting neutral mucins is related to the production and release of the putative sex pheromone.  相似文献   
108.
Cantanhez National Park in southern Guinea-Bissau is a mosaic of forest, mangrove, savanna, and agricultural fields, with a high prevalence of oil-palm trees (Elaeis guineensis). It hosts many different animal species, including the chimpanzee (Pan troglodytes verus). Very little is known about the ecology of chimpanzees inhabiting this area. The main aims of this study were to evaluate chimpanzee nesting behavior, define trends of habitat use, and estimate chimpanzee density in four separate forests by applying the marked nest counts methodology. From the 287 new nests counted, 92% were built in oil-palm trees with a significantly higher frequency of nests in the forest edge than in forest cores. Differences in nest detection rates were observed in the four monitored forests, with two forests being more important for chimpanzee's nesting demands. The number of nests documented in the forests seemed to be correlated with the frequency of other signs of chimpanzee activity. Although chimpanzees selected nests on the forest edge, they were most frequently observed in forest core areas. Constraints associated with estimating chimpanzee density through oil-palm nest counting are discussed.  相似文献   
109.
Olfactory sensitivity to bile salts is wide-spread in teleosts; however, which bile salts are released in sufficient quantities to be detected is unclear. The current study identified bile salts in the intestinal and bile fluids of Solea senegalensis by mass spectrometry–liquid chromatography and assessed their olfactory potency by the electro-olfactogram. The main bile salts identified in the bile were taurocholic acid (342 mM) and taurolithocholic acid (271 mM) plus a third, unidentified, bile salt of 532.3 Da. These three were also present in the intestinal fluid (taurocholic acid, 4.13 mM; taurolithocholic acid, 0.4 mM). In sole-conditioned water, only taurocholic acid (0.31 μM) was released in sufficient quantities to be measured (release rate: 24 nmol kg−1 min−1). Sole had high olfactory sensitivity to taurocholic acid but not to taurolithocholic acid. Furthermore, olfactory sensitivity was higher in the upper (right) olfactory epithelium than the lower (left). These two bile acids contribute about 40% of the olfactory potency of intestinal fluid and account for the difference in potency at the two epithelia. Taurocholic acid (but not taurolithocholic acid), and possibly other types of bile acid not tested, could be used as chemical signals and the upper olfactory epithelium is specialised for their detection.  相似文献   
110.
This study examines the extent to which interactions among two common alpine/subalpine plant species and their neighbours at the Bogong High Plains in southern Australia are characterized by competition or facilitation. The two target species were Celmisia pugioniformis (Asteraceae) and Carex breviculmis (Cyperaceae). Biotic interactions were examined using vegetation removal manipulations over three growing seasons at five sites across the altitudinal range of tall alpine herbfield communities. Observations recorded growth and mortality. Results for C. pugioniformis clearly indicated facilitation as a dominant process across all sites and seasons. Plants that had their neighbours removed tended to perform worse than plants that had their neighbours left intact. Growth observations for Ca. breviculmis were less clear, but again suggested facilitation. Mortality was distinctly higher among Ca. breviculmis individuals that had their neighbours removed relative to those with neighbours left intact. Results collectively suggest the removal of neighbours acts to reduce growth and increase mortality in C. pugioniformis and Ca. breviculmis throughout the altitudinal range of tall alpine herbfields at the Bogong High Plains. Facilitative and competitive interactions need to be recognized in efforts aimed at mitigating climate change‐associated impacts on the ecology of alpine plant communities. The extent to which biotic interactions may exacerbate or buffer abiotic change is difficult to predict, emphasizing the need for ecological monitoring.  相似文献   
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