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1.
We analyzed, by env and gag heteroduplex mobility assay, 149 human immunodeficiency virus (HIV-1) positive samples collected in Ceará during the year 2000. The prevalence of subtype B was 81.2% and the prevalence of subtype F and B/F recombinants were both 2.7%. Eight (5.4%) and 12 (8%) out of 149 samples showed indeterminate results in the env and gag analysis respectively. By FokI restriction fragment length polymorphism, 34% of the subtype B samples were identified as the typical Brazilian subtype B.In the present study, we identified HIV-1 subtype F and B/F in Ceará for the first time. Our results contribute to the understanding of HIV in Brazil, and may prove useful for the development of vaccine candidates.  相似文献   

2.
With the purpose of analyzing the horizontal distribution of the zooplankton community of the Tucuruí Reservoir in the State of Pará, Brazil, collections were made at 16 stations during August 1988. The stations cover the regions called Caraipé (C), Ara?agi (B) and Arar?o (A), and represent the different compartments of this ecosystem in regard to the morphometry and the presence or absence of "flooded forest". Our findings showed the existence of three compartments with different limnological characteristics determined as a function of the system's morphometry, a factor that may have influenced the horizontal circulation of the reservoir's water and, consequently, led to physical, chemical and biological differences at each of the sampled stations. All the stations presented physical and chemical stratification and layers of total anoxia or reduced concentrations of oxygen dissolved at depths corresponding to the limit of the euphotic zone. With regard to the zooplankton, a differentiated distribution that was mainly quantitative was found among the compartments (density of organisms and proportion among the species) in the case of Cladocera and Copepoda, and basically qualitative in the case of Rotifera. On the other hand, the greatest densities of organisms for all the groups were recorded at the Caraipé stations. As for the spatial distribution, some species were more restricted or more abundant at given stations. Among the Cladocera, there was a greater abundance of Moina minuta, Bosmina hagmani and Bosminopsis deitersi at the Ara?agi stations, while C. cornuta intermedia, C. cornuta rigaudi and C. cornuta cornuta were more plentiful in the Caraipé and Diaphanosoma birgei in the Arar?o. Among the Rotifera, Trochosphaera aequatoriales and Lecane proiecta, Ascomorpha ecaudis, besides Polyartha cf vulgaris were restricted, respectively, to the Caraipé, Ara?agi and Arar?o stations, while the others, such as Keratella americana and Collotheca sp., were more broadly distributed. As regards Copepoda Calanoida, the dominating species was found to be Notodiaptomus maracaibenses, followed by Notodiaptomus henseni and Argyrodiaptomus azevedoi. The most abundant Cyclopoda species was Thermocyclops minutus, although Thermocyclops decipiens, Mesocyclops longisetus, Mesocyclops meridianus e Metacyclops sp. were also found.  相似文献   

3.
Velho  L. F. M.  Lansac-Tôha  F. A.  Bonecker  C. C.  Bini  L. M.  Rossa  D. C. 《Hydrobiologia》2001,(1):385-391
The assessment of factors that determine the spatial distribution of zooplankton abundance is a central issue in zooplankton ecology. Since these factors are, in the most cases, spatially autocorrelated, especially in reservoirs, it is frequently difficult to isolate the primary causes that explain the variation in zooplankton abundance. In this paper, the spatial variation of copepods in Corumbá Reservoir (Goiás, Brazil) was studied. Sets of variables were used to model copepod abundance variation: limnology (abiotic variables), phytoplankton and spatial position of sampling sites. The copepod assemblage was composed of Thermocyclops minutus, Thermocyclops decipiens, Mesocyclops longisetus and Notodiaptomus iheringi. Along the reservoir's main axis, abundance increases, albeit not linearly, towards the lacustrine zone. High abundance, similar to that found in the lacustrine region, was also observed in the lateral arms. These patterns were very similar for different years and seasons. Copepods were significantly correlated with phytoplankton and geography. After controlling for the effect of space, the relationship between copepods and phytoplankton was not significant (partial Mantel test). This result indicates that hydrology is the primary process that controls not only the abundance of copepods, but also limnological features and food resources, which are commonly used to explain variations in zooplankton abundance.  相似文献   

4.
Melioidosis has been considered an emerging disease in Brazil since the first cases were reported to occur in the northeast region. This study investigated two municipalities in Ceará state where melioidosis cases have been confirmed to occur. Burkholderia pseudomallei was isolated in 26 (4.3%) of 600 samples in the dry and rainy seasons.Melioidosis is an endemic disease in Southeast Asia and northern Australia (2, 4) and also occurs sporadically in other parts of the world (3, 7). Human melioidosis was reported to occur in Brazil only in 2003, when a family outbreak afflicted four sisters in the rural part of the municipality of Tejuçuoca, Ceará state (14). After this episode, there was one reported case of melioidosis in 2004 in the rural area of Banabuiú, Ceará (14). And in 2005, a case of melioidosis associated with near drowning after a car accident was confirmed to occur in Aracoiaba, Ceará (11).The goal of this study was to investigate the Tejuçuoca and Banabuiú municipalities, where human cases of melioidosis have been confirmed to occur, and to gain a better understanding of the ecology of Burkholderia pseudomallei in this region.We chose as central points of the study the residences and surrounding areas of the melioidosis patients in the rural areas of Banabuiú (5°18′35″S, 38°55′14″W) and Tejuçuoca (03°59′20″S, 39°34′50′W) (Fig. (Fig.1).1). There are two well-defined seasons in each of these locations: one rainy (running from January to May) and one dry (from June to December). A total of 600 samples were collected at five sites in Tejuçuoca (T1, T2, T3, T4, and T5) and five in Banabuiú (B1, B2, B3, B4, and B5), distributed as follows (Fig. (Fig.2):2): backyards (B1 and T1), places shaded by trees (B2 and T2), water courses (B3 and T3), wet places (B4 and T4), and stock breeding areas (B5 and T5).Open in a separate windowFIG. 1.Municipalities of Banabuiú (5°18′35″S, 38°55′14″W) and Tejuçuoca (03°59′20″S, 39°34′50″W).Open in a separate windowFIG. 2.Soil sampling sites in Banabuiú and Tejuçuoca.Once a month for 12 months (a complete dry/rainy cycle), five samples were gathered at five different depths: at the surface and at 10, 20, 30 and 40 cm (Table (Table1).1). The samples were gathered according to the method used by Inglis et al. (9). Additionally, the sample processing and B. pseudomallei identification were carried out as previously reported (1, 8, 9).

TABLE 1.

Distribution of samples with isolates by site and soil depth
Sitesa and depth (cm)No. of B. pseudomallei isolates in samples from:
Banabuiú (n = 300)Tejuçuoca (n = 300)Total (n = 600)
B1/T13
    Surface2
    10
    201
    30
    40
B2/T21
    Surface1
    10
    20
    30
    40
B3/T315
    Surface2
    102
    204
    303
    404
B4/T45
    Surface
    101
    201
    3011
    401
B5/T52
    Surface
    10
    20
    302
    40
Total62026
Open in a separate windowaSites designated with B are in Banabuiú, and sites designated with T are in Tejuçuoca. See the text for details.The data on weather and soil composition were obtained from specialized government institutions, such as FUNCEME, IPECE, and EMBRAPA. The average annual temperature in both municipalities is between 26 and 28°C. In 2007, the annual rainfall in Tejuçuoca was 496.8 mm, and that in Banabuiú was 766.8 mm. There are a range of soil types in both Tejuçuoca and Banabuiú: noncalcic brown, sodic planossolic, red-yellow podzolic, and litholic. In Banabuiú, there are also alluvial and cambisol soils. The characteristic vegetation in both municipalities is caatinga (scrublands).There were isolates of B. pseudomallei in 26 (4.3%) of the 600 samples collected. The bacterium was isolated at a rate (3%) similar to that previously reported (9). The bacterium isolation occurred in both the dry (53.8%) and the rainy (46.2%) seasons. Tejuçuoca represented 76.9% (20/26) of the strains isolated. Four sites in Tejuçuoca (T1, T3, T4, and T5) and three in Banabuiú (B1, B2, and B4) presented isolates of the bacterium (Table (Table1).1). The isolation of the B. pseudomallei strains varied from the surface down to 40 cm. However, 17 of the 26 positive samples (65.3%) were found at depths between 20 and 40 cm (Table (Table1).1). Only two isolates were found at the surface during the dry season.A study in Vietnam (13) and one in Australia (9) reported the presence of B. pseudomallei near the houses of melioidosis patients. In our study, the same thing happened. Site T3 (15/26; 57.6%) was located 290 m from the patient''s house, as reported by the Rolim group (14).B. pseudomallei was isolated from a sheep paddock in Australia, where animals sought shelter below mango and fig trees (17). In our study, the bacterium was isolated at site T5, a goat corral alongside the house where the outbreak occurred in Tejuçuoca. Four sites in places shaded by trees yielded positive samples (30.7%) in both Tejuçuoca (palm trees) and Banabuiú (mango trees). Additionally, B. pseudomallei was isolated on three occasions from a cornfield (site 4B) located alongside the house of the melioidosis patient in Banabuiú.In the main areas of endemicity, the disease is more prevalent in the rainy season (4, 5, 16). The outbreak in Tejuçuoca was related to rainfall (14). Besides the association of cases of the disease with rainfall itself, the isolation of B. pseudomallei in soil and water was also demonstrated during the dry season (12, 15). An Australian study isolated strains from soil and water during the dry and rainy seasons (17). A Thai study also reported B. pseudomallei in the dry season (18). In our study, the isolation of B. pseudomallei took place either at the end of the wet season or in the dry months. Fourteen of the positive samples (53.8%) were collected during the dry season, albeit near a river or reservoir (sites T3 and B4).Physical, biological, and chemical soil features appear to influence the survival of B. pseudomallei (6, 10). In the present study, the soil was classified as litholic with sandy or clayey textures. It is susceptible to erosion, and when there is a lack of water, it is subject to salinization. During the dry season, the clay layer becomes dried, cracked, and very hard. During the rainy season, it becomes soggy and sticky. The isolation of B. pseudomallei in the dry season is possibly related to the capacity for adaptation of this soil, since the extreme conditions of lithosols do not prevent the bacterial growth and survival.It has been shown that B. pseudomallei is more often isolated at depths between 25 and 45 cm (17). In our study, 65.3% of the positive samples were taken at depths between 20 and 40 cm. Moreover, of these 17 samples, 10 (58.8%) were collected during the dry months. Also, unlike in other regions, two positive samples were taken from the surface in the period without rainfall.The rainfall in Tejuçuoca and Banabuiú is generally low, and temperatures do not vary significantly during the year. Therefore, the isolation of B. pseudomallei in these places occurs outside the rainfall, temperature, and moisture conditions observed in other regions of endemicity. Our data thus suggest that peculiar environmental features, such as soil composition, might favor the multiplication of B. pseudomallei in northeast Brazil.  相似文献   

5.
AIMS: To investigate whether modifications in Yersinia pestis isolates from three plague foci from the state of Ceará, Brazil, had occurred over the years as a consequence of genetic adaptation to the environment. METHODS AND RESULTS: The isolates were studied with respect to susceptibility to antimicrobial drugs, plasmid and protein profiling, pigmentation on Congo red-agar plates, and the presence of some pathogenicity genes using PCR. Most of the expected virulence markers were detected in the cultures examined. There was no evidence of any alteration that could be associated with their origin (patients, rodents and fleas) or period of isolation (1971-1997). CONCLUSIONS, SIGNIFICANCE AND IMPACT OF THE STUDY: Phenotypic or genotypic changes were not detected in the cultures examined. However, the results obtained will serve as a reference to follow the evolution of Y. pestis in these foci.  相似文献   

6.
Burkholderia pseudomallei, the causative agent of melioidosis was found in a small cluster of cases in Teju?uoca, Ceará, Brazil. Tests were carried out to determine its phenotypic characteristics: colony morphology on Ashdown agar and MacConkey agar, biochemical profile in conventional biochemical tests and API 20NE, arabinose assimilation and susceptibility testing by disk diffusion, comparing with data in the literature. This study confirms the presence of B. pseudomallei in Brazil and describes its characteristics.  相似文献   

7.
Brazil is one of the leading exporters of ornamental fishes, mostly freshwater; however, monitoring of the trade is nearly non-existent in the country. This paper provides an initial assessment of a new venture, the marine aquarium fish trade at Ceará State, northeast Brazil, aiming to document the species traded, to provide preliminary estimates of numbers of specimens traded, and to identify priorities in data collection and monitoring. A total of 143 species and 199 304 fishes were traded. From the total, 109 species were native and represented 84% of the fishes traded. Thirty-four exotic species figured on the permits and amounted to nearly 16% of the exports; however, most of them consist of misidentified native species. Nearly 90% of the fish trade was directed to the international market. Official figures represent an underestimation of the total number of captured specimens.  相似文献   

8.
Litterfall consumption and predation on propagules is high in Indo-west-Pacific mangroves and low in Atlantic-east-Pacific ones. However, data for the latter area comes only from Caribbean and subtropical North American mangroves. South American data on litterfall consumption contradicts this view but data on predation on propagules are scarce. We measured predation on Rhizophora mangle, Avicennia schaueriana and Laguncularia racemosa propagules and seedlings and related to densities of large (>1.5 m high) and small (1–1.5 m) plants in mature and regenerating mangroves in Ceará state, Brazil. Predation on propagules was the highest among American mangroves (R. mange, >47%; A. schaueriana, >97%; L. racemosa, >83%), especially in the regenerating area. Predation on seedlings was low (maximum of 14% for R. mangle) and did not hamper growth. The dominance of large R. mangle trees in the mature mangrove is consistent with the lower predation on its propagules but the high proportions of small plants of other species indicate that dominance is achieved by mechanisms other than predation. In the regenerating mangrove, dominance of large and small L. racemosa and A. schaueriana plants is not consistent with the high predation on their propagules. Therefore, predation is not the main determinant of the species composition in this mangrove system.  相似文献   

9.
I review the distribution of genus Alouattain the Marajó Archipelago based on geographic variation of pelage color patterns. Specific differences exist among the labeled specimens at Museu Paraense Emílio Goeldi, which are confirmed via new field information from wild populations. The animals from Marajó, Caviana, and Mexiana Islands possess color patterns of Alouatta belzebul,while Alouatta seniculusis confirmed as the species that inhabits Gurupá Island. The high variability of pelage coloration of the animals from Marajó, Caviana, and Mexiana Islands includes all phenotypes formerly designated as different subspecies. The howler populations from these three islands belong to the same subspecies as those populations that inhabit the region of Tucurui dam reservoir (area 4). Finally, it seems that, as also suggested by chromosome studies, A. belzebulprobably comprises different epiphenotypes without taxonomic validity.  相似文献   

10.
I review the distribution of genus Alouattain the Marajó Archipelago based on geographic variation of pelage color patterns. Specific differences exist among the labeled specimens at Museu Paraense Emílio Goeldi, which are confirmed via new field information from wild populations. The animals from Marajó, Caviana, and Mexiana Islands possess color patterns of Alouatta belzebul,while Alouatta seniculusis confirmed as the species that inhabits Gurupá Island. The high variability of pelage coloration of the animals from Marajó, Caviana, and Mexiana Islands includes all phenotypes formerly designated as different subspecies. The howler populations from these three islands belong to the same subspecies as those populations that inhabit the region of Tucurui dam reservoir (area 4). Finally, it seems that, as also suggested by chromosome studies, A. belzebulprobably comprises different epiphenotypes without taxonomic validity.  相似文献   

11.
We conducted a survey to determine the vectors of malaria in six localities of Serra do Navio municipality, State of Amapá, from 1990 to 1991. Malaria infection rates of 29.3%, 6.2% and 20.4% were detected by human blood smears in Col?nia Agua Branca, Porto Terezinha and Arrependido, respectively. There was no malaria infection detected in Serra do Navio. Fifteen species were identified among 3,053 anopheline mosquitoes collected by human bait and 64.4% were identified as Anopheles albitarsis s.l., 16.7% An. braziliensis, 9.5% An. nuneztovari and 5.8% An. triannulatus. An. darlingi, the main vector of malaria in the Amazon region of Brazil, was scare. Using enzyme-linked immunosorbent assay (ELISA), a total positive rate of 0.8% (23/2876) was found for six species: fifteen An. albitarsis s.l., four An. nuneztovari, and one of each: An. braziliensis, An. triannulatus, An. oswaldoi and An. rangeli. Nine of 23 positive mosquitoes were infected with Plasmodium malariae, eight with P. vivax VK210, three with P. vivax VK247 and three with P. falciparum. Since An. albitarsis s.l. was collected feeding on humans, was present in the highest density and was positive by ELISA for malaria sporozoites, it probably plays an important role in malaria transmission in this area.  相似文献   

12.
In 2009, the World Health Organization (WHO) issued a new guideline that stratifies dengue-affected patients into severe (SD) and non-severe dengue (NSD) (with or without warning signs). To evaluate the new recommendations, we completed a retrospective cross-sectional study of the dengue haemorrhagic fever (DHF) cases reported during an outbreak in 2011 in northeastern Brazil. We investigated 84 suspected DHF patients, including 45 (53.6%) males and 39 (46.4%) females. The ages of the patients ranged from five-83 years and the median age was 29. According to the DHF/dengue shock syndrome classification, 53 (63.1%) patients were classified as having dengue fever and 31 (36.9%) as having DHF. According to the 2009 WHO classification, 32 (38.1%) patients were grouped as having NSD [4 (4.8%) without warning signs and 28 (33.3%) with warning signs] and 52 (61.9%) as having SD. A better performance of the revised classification in the detection of severe clinical manifestations allows for an improved detection of patients with SD and may reduce deaths. The revised classification will not only facilitate effective screening and patient management, but will also enable the collection of standardised surveillance data for future epidemiological and clinical studies.  相似文献   

13.
Presently, the State of Ceará reports the largest percentage of human rabies cases originated from wild animals in Brazil, transmitted by the principal simian species, the tamarin (Callithrix jacchus), found in various locations throughout the State, but concentrated along the coast. Epidemiological studies indicated that possibly the same virus caused the deaths in humans and non-human primates. This rabies virus seem to be different from all other identified so far.  相似文献   

14.
《Small Ruminant Research》2007,70(1-3):79-82
One hundred and sixty-nine fragments of heart muscle collected from goats in the State of Ceará, Brazil, were analyzed by mouse bioassay with the aim of isolating Toxoplasma gondii. Two T. gondii isolates, named G1 and G2, were obtained and were characterized by PCR-RFLP. In addition, their virulence was evaluated by experimental inoculation into BALB/c mice. The G1 isolate presented high virulence leading to 100% mortality of mice after inoculations with 101, 102, and 103 tachyzoites. The G2 isolate presented low virulence and none of the doses tested lead to mortality of mice. The PCR-RFLP analysis showed that the two isolates are recombinants of the types I/III. However, they differ in the haplotype combination for the genotypes analyzed.  相似文献   

15.
Dengue fever is a major public health problem worldwide, caused by any of four virus (DENV-1, DENV-2, DENV-3 and DENV-4; Flaviviridae: Flavivirus), transmitted by Aedes aegypti mosquito. Reducing the levels of infestation by A. aegypti is one of the few current strategies to control dengue fever. Entomological indicators are used by dengue national control program to measure the infestation of A. aegypti, but little is known about predictive power of these indicators to measure dengue risk. In this spatial case-control study, we analyzed the spatial distribution of the risk of dengue and the influence of entomological indicators of A. aegypti in its egg, larva-pupa and adult stages occurring in a mid-size city in the state of São Paulo. The dengue cases were those confirmed by the city''s epidemiological surveillance system and the controls were obtained through random selection of points within the perimeter of the inhabited area. The values of the entomological indicators were extrapolated for the entire study area through the geostatistical ordinary kriging technique. For each case and control, the respective indicator values were obtained, according with its geographical coordinates and analyzed by using a generalized additive model. Dengue incidence demonstrated a seasonal behavior, as well as the entomological indicators of all mosquito''s evolutionary stages. The infestation did not present a significant variation in intensity and was not a limiting or determining factor of the occurrence of cases in the municipality. The risk maps of the disease from crude and adjusted generalized additive models did not present differences, suggesting that areas with the highest values of entomological indicators were not associated with the incidence of dengue. The inclusion of other variables in the generalized additive models may reveal the modulatory effect for the risk of the disease, which is not found in this study.  相似文献   

16.
The myelodysplastic syndromes (MDS) are clonal hematopoietic diseases characterized by medullary dysplasia, cytopenias, and frequent evolution to acute myeloid leukemia. In 1982, the French-American-British (FAB) group proposed a classification for the MDS, based on morphological characteristics of peripheral blood and of the bone marrow. Later, cytogenetics proved to be a useful tool for the refinement of prognosis, through the use of the International Prognosis Score System (IPSS), as well as through evidence of clonality. Recently, the World Health Organization (WHO) proposed a new classification for the MDS, based on significant modifications of the FAB proposal, with the inclusion of chromosome analysis. A cytogenetic analysis was made of 17 patients with symptoms of MDS in the State of Para, based on WHO recommendations, and application of the IPSS. Good metaphases were obtained for 13 patients; 12 had a normal karyotype and only one had a clonal abnormality, del(3)(p25). The genes related to neoplastic processes that have been mapped to 3p are: XPC in 3p25.1 and FANCD2 and VHL in 3p25-26. Four patients had classic symptoms of MDS; in the rest the possibility of MDS was excluded or several months of observation before diagnosis were recommended. Among those with MDS, it was not possible to apply IPSS and WHO recommendations, because fundamental data were lacking, specifically the medullary blast and ring sideroblast counts. We advocate the implementation of routine cytogenetic analyses for the study of MDS, especially in patients with moderate hematopoietic dysplasia.  相似文献   

17.
18.
Electrophoresis of rotavirus RNA in polyacrylamide gel was carried out by using faecal samples collected from children living in the peripheral area of Belém, Brazil. Typical rotavirus profiles (eleven bands) were noted in 46(76.7%) out of 60 ELISA rotavirus positive specimens. According to the electrophoretic patterns, 5(10.9%) were classified as subgroup I, while 41(89.1%) of them as subgroup II. Lacking of bands 10 and 11 in 14(23.3%) samples did not allow us to classify their electropherotypes. The profile coded as "1N2L" was the predominant one, accounting for 65.2% of the classified strains.  相似文献   

19.
Knowledge of epidemiological and mycological characteristics of onychomycosis has been noted by many authors as being an important tool for control of these fungal infections. This study seeks to improve knowledge of onychomycosis epidemiology and mycological features. Samples were taken from infected fingernails and toenails of 976 patients undergoing treatment at a respected Dermatology Center in Ceará, Fortaleza, CE, Brazil. Specimens from 512 patients (52%) were positive for onychomycosis. From the culture-positive samples, yeasts of the genus Candida (C. albicans, C. tropicalis, C. krusei, C. parapsilosis) were dominant. The dermatophytes isolated (Trichophyton rubrum, T. tonsurans, T. mentagrophytes var. mentagrophytes) were dominant in 46 patients (12.99%). The mould Fusarium spp. was isolated from 29 patients (8.19%). Yeast of the genus Candida is the main causal factor in onychomycosis in our region. Also, the study showed the importance of performing direct examination and culture in diagnosis of onychomycosis.  相似文献   

20.
This study reports the Length-Weight Relationships (LWR) for 10 freshwater fish species sampled in the Atlantic Rainforest, Southern Brazil. Sampling was conducted between 2016 and 2017, in nine streams, using electrofishing. Collected fishes were fixed in formalin, and thus some shrinking was unavoidable. The values of parameter b of the LWR (W = aLb) ranged between 2.5 and 3.5. We report for the first time the LWR for seven species: Geophagus iporanguensis, Isbrueckerichthys duseni, Hypostomus interruptus, Kronichthys lacerta, Chasmocranu lopezi, Astyanax lacustris e Neoplecostomus ribeirensis. We highlight the importance of the LWR data in supporting further studies on fish stocks and environment in the Atlantic Rainforest, thereby contributing to the database needed to develop fisheries management and maintenance of ecosystem services.  相似文献   

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