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1.
Due to the spread of Visceral leishmaniasis in Brazilian territory, this research was undertaken with the objective to identify the sandfly fauna and aspects of the species behavior in forest and anthropic environments in Paraná State, Brazil. The sandfly captures were sporadically carried out in 37 municipalities of the Paraná state, during the period from March 2004 to November 2005. Each municipality was once visited, when Falc?o traps were installed during three consecutive nights in forested fragments and anthropic environments; captures with Shannon traps installed in forests and edge of forests, inspection of walls and electric aspiration in domiciles and forested areas were sporadically undertaken. The data analysis was based on estimates of frequency and abundance of the species, by five native landscapes. A total of 38,662 specimens belonging to 23 species were captured. Nyssomyia neivai (Pinto) (75.6%), Ny. whitmani (Antunes & Coutinho) (10.1%), Migonemyia migonei (Fran?a) (7.8%), Expapillata firmatoi (Barreto et al.) (2.1%) and Pintomyia fischeri (Pinto) (1.6%) together constituted 97.2% of the phlebotomine collected. High frequencies of sand flies were found in forests, henhouses, pig-pens and domiciles. The three most frequent species have been implicated in transmission of tegumentary leishmaniasis in Paraná and in the Brazilian Southeastern and Southern Regions. Lutzomyia longipalpis (Lutz & Neiva), the visceral leishmaniasis vector, was not found, however Lutzomyia gaminariai (Cordero et al.), female of which is similar to that of Lu. longipalpis was captured, raising the need to investigate its behavior, including as regard to the vectorial competence.  相似文献   

2.
New data are presented on the sex chromosomes of the fish species Eigenmannia virescens (Gymnotiformes, Sternopygidae). A new finding, involving the occurrence of ZZ/ZW sex chromosomes, is described in specimens sampled from the S?o Francisco and Amazon river basins in Brazil. All individuals had a chromosome number of 2n = 38. The homologs of the sex chromosome pair from the S?o Francisco river basin sample differed only in their morphology, while those from the Amazonian sample differed both in morphology and heterochromatin pattern. A possible model for the evolution of the sex chromosomes in E. virescens is proposed, including data from populations from the Paraná (Brazil) river basin, in which male heterogamety has already been described. The occurrence of different sex chromosome systems in species and populations of the neotropical freshwater fish fauna is discussed.  相似文献   

3.
The aim of this study was to determine the prevalence of malaria infection and antibodies against the repetitive epitopes of the circumsporozoite (CS) proteins of Plasmodium falciparum, P. malariae, P. vivax VK210, P. vivax VK247, and P. vivax-like in individuals living in the states of Rond?nia, Pará, Mato Grosso, Amazonas, and Acre. Active malaria transmission was occurring in all studied sites, except in Acre. P. falciparum was the predominant species in Pará and Rond?nia and P. vivax in Mato Grosso. Infection by P. malariae was low but this Plasmodium species was detected in Rond?nia (3.5%), Mato Grosso (2.5%), and Pará (0.8%). High prevalence and levels of serological reactivity against the CS repeat peptides of P. falciparum were detected in Rond?nia (93%) and Pará (85%). Sera containing antibodies against the CS repeat of P. malariae occurred more frequently in Rond?nia (79%), Pará (76%), and Amazonas (68%). Antibodies against the repeat epitope of the standard CS protein of P. vivax VK210, P. vivax VK247, and P. vivax-like were more frequent in Rond?nia, Pará, and Mato Grosso. The high frequency of reactions to P. malariae in most of the areas suggests that the infection by this Plasmodium species has been underestimated in Brazil.  相似文献   

4.
5.
Arvelius albopunctatus (De Geer) is widely distributed in the Neotropical region, being an important pest of Solanaceae. Color variation of nymphs was described for this and other pentatomid species and their knowledge is essential for an early identification. From December 2005 to July 2006 nymphs and adults of A. albopunctatus were collected in forest fragments in Criciúma, I?ara, Maracajá and Araranguá (SC, Brazil). Known morphs of nymphs of both 4th and 5th instars were observed, as well as three new morphs, here described and named red morph (4th and 5th instars), green morph (4th and 5th instars) and orange morph (5th instar).  相似文献   

6.
The morphological discrimination between the species Astyanax altiparanae and A. asuncionensis of the upper Paraná River and Paraguay River basins, respectively, has always been difficult. Two D-loop haplogroups of A. altiparanae are known, one with the presence (AltoPR) or the absence (AltoPR-D) of a 32-bp block similar to that in A. asuncionensis. We examined these samples to characterize A. altiparanae and verify whether A. asuncionensis occurred in the upper Paraná River prior to the submergence of the Sete Quedas Falls when Itaipu reservoir was impounded. D-loop sequences were analyzed in A. altiparanae of the upper Paraná and Igua?u Rivers and those of A. asuncionensis of the upper Paraguay River. The haplogroup AltoPR was found at all sites of the upper Paraná and Igua?u Rivers, whereas AltoPR-D occurred in the Itaipu reservoir, floodplain and in the Tietê and Grande Rivers. Two haplogroups of A. asuncionensis were identified and both did not have the 32-bp block. However, AltoPR and AltoPR-D differed from one another in 5.1% of their bases and between 8.9 and 12.5% with regard to the haplogroups of the upper Paraguay basin. Further, AltoPR-D occurred in the Grande River upstream the Marimbondo Falls and other older reservoirs than Itaipu. The results reject the hypothesis of the establishment of A. asuncionensis and suggest that the haplogroup AltoPR-D existed in the upper Paraná River before the impounding of the Itaipu reservoir. Moreover, morphological similarity and high genetic variation within the altiparanae/asuncionensis group suggest the existence of a cryptic species complex.  相似文献   

7.
In the present study, we applied Chromosome Aberration (CA) and Micronucleus (MN) tests to Allium cepa root cells, in order to evaluate the water quality of Guaecá river. This river, located in the city of S?o Sebasti?o, SP, Brazil, had been affected by an oil pipeline leak. Chemical analyses of Total Petroleum Hydrocarbons (TPHs) and Polycyclic Aromatic Hydrocarbons (PAHs) were also carried out in water samples, collected in July 2005 (dry season) and February 2006 (rainy season) in 4 different river sites. The largest CA and MN incidence in the meristematic cells of A. cepa was observed after exposure to water sample collected during the dry season, at the spring of the river, where the oil leak has arisen. The F(1) cells from roots exposed to such sample (non-merismatic region) were also analyzed for the incidence of MN, showing a larger frequency of irregularities, indicating a possible development of CA into MN. Lastly, our study reveals a direct correlation between water chemical analyses (contamination by TPHs and PAHs) and both genotoxic and mutagenic effects observed in exposed A. cepa cells.  相似文献   

8.
The abundance and aggregation of eggs of Aedes aegypti L. and Aedes albopictus Skuse was evaluated in the municipalities of Cambé, Ibipor?, Jacarezinho, Maringá and Paranavaí, in the State of Paraná, Brazil by means of oviposition traps. Of the 225 installed traps, 100 were registered as positive for eggs; 4140 eggs were collected, thus demonstrating an highly aggregate distribution. Both species were registered in Cambé, Jacarezinho, Maringá and Paranavaí. Ae. albopictus was generally less abundant and was not present in Ibipor? nor in the oviposition traps of a second collection of Maringá. The relation between sexes for Ae. aegypti was approximately 1:1. In the comparison of the number of adults collected between the two species, a negative correlation was obtained in the samples of Maringá and Cambé, what was attributed the seasonality of these populations. The coexistence of these species indicates that both are under pressure by the control programs, therefore specific evaluations are necessary.  相似文献   

9.
We used mitochondrial DNA sequences of 12S and 16S ribosomal RNA genes to reconstruct phylogenetic relationships of the nine species of South American aquatic hylids known as paradoxical frogs. Pseudis minuta and P. cardosoi form the sister-group to a clade comprising Lysapsus and the remaining Pseudis. We suggest the resurrection of Podonectes, including P. minutus and P. cardosoi, to avoid the nonmonophyly of Pseudis. Some doubt is cast on the species status of P. cardosoi. Lysapsus limellum, P. bolbodactyla, and P. paradoxa each may comprise more than one species, but lack of comprehensive geographic and morphological appraisals precludes taxonomic changes. Biogeographic implications of the phylogeny are discussed. The correlation between hydrographic basins and Pseudis species is not fully supported, and a recent contact between Amazon populations in eastern Bolivia and western Brazil (Rond?nia) and Paraná basin populations in the Pantanal is suggested. A dispersal-vicariance analysis showed that major diversification of Pseudis and Lysapsus species occurred in the Brazilian Shield, and that the presence of P. paradoxa and L. limellum in the Amazon and Paraná basins is due to recent dispersals. Evidence suggests a vicariant event, most likely caused by Miocene marine introgressions, as the cause for the restricted distribution of L. laevis in the Guiana Shield.  相似文献   

10.
Diplectanum monticellii n. sp. is described from the gills of Cynoscion leiarchus, a marine Sciaenidae, from Itacuru?á, Rio de Janeiro (type locality); Baía de Guaratuba, Paraná; and Pontal do Sul, Paraná in Brazil. The new species is characterized by the following features: bell-shaped male copulatory organ with a sleevelike base, accessory piece absent, vas deferens looping left intestinal cecum, vaginal aperture sinistroventral, and ventral anchor with elongate superficial and deep roots.  相似文献   

11.
Nine STR loci (CSF1PO, TPOX, TH01, F13A01, FESFPS, VWA, D16S539, D7S820, and D13S317) were analyzed in unrelated Ng?bé and Emberá Amerindians of Panama. The chi-square test demonstrated statistically significant differences (P < 0.001) in the allele frequencies for all markers except one (D16S539; P < 0.01). Both populations shared their alleles with the highest frequencies in seven loci. However, there were also noticeable differences at the TPOX locus, which showed its highest frequencies at alleles 11 (0.48) and 6 (0.54) for the Ng?é and Emberá, respectively. Interestingly, these alleles are present in one population and are absent in the other, suggesting that they could be distinctive for each population. These results demonstrate that, despite the fact that each population belongs to a different linguistic stock [Chibchan (Ng?bé) and Chocoan (Emberá)], both retain strong similarities in their allele-frequency distributions. Three loci (TPOX, VWA, and F13A01) in the Ng?bé and two loci (TH01 and TPOX) in the Emberá departed from Hardy-Weinberg equilibrium. The analysis of the STR markers demonstrates that, despite their low levels of genetic polymorphisms, most of them could be informative for forensic purposes, showing a combined power of discrimination of 0.9999 for both Amerindian populations. However, powers of exclusion in the Ng?bé were very low, particularly at the TH01 (0.04) and FESFPS (0.08) loci. The combined powers of exclusion were 0.9338 and 0.9890 for the Ng?bé and the Emberá, respectively. Furthermore, the combined typical paternity index in the Ng?bé was considerably low (2.58), and in the Emberá it was 40.44, which is also very low. The low genetic polymorphism levels suggest that theuse of additional loci supplementing the battery of the nine loci is recommended for paternity and forensic tests in both populations, particularly for the Ng?bé.  相似文献   

12.
A malaria control pilot project was developed in the Urupá agro-industrial farm that is situated in the State of Rond?nia (Western Amazon Region, Brazil). Around 180 inhabitants had been surveyed for the past five years. The control measures were based on (1) training a community agent to perform on the spot microscopical diagnosis of malaria and to treat the uncomplicated cases of malaria; (2) limiting the use of insecticides to a short period before the high transmission season. This resulted in a significant reduction in the time between the onset of clinical symptoms and specific chemotherapy which fell from 3.5 to 1.3 days. In relation to the previous three reference years the total number of malaria cases was reduced to 50% in the first year and to 25% in the second year. The introduction of these measures coincided with pronounced reduction in the frequency of Plasmodium falciparum infections but this was less marked for P. vivax infections. In the second year of the pilot experiment there was no P. falciparum transmission on the farm. During the last decade there was a general decrease in the endemicity of malaria in the State of Rond?nia. The linear regression coefficient values indicate that the decline was more pronounced in Urupá than in the general municipality and that the falciparum malaria API in Urupá farm is significantly lower than in the general municipality of Candeias were the farm is situated.  相似文献   

13.
An outbreak of coccidioidomycosis is described that involved three individuals and eight of their dogs, who had engaged in a successful hunt for nine-banded armadillos (Dasypus novemcinctus) in the environs of Oeiras, a community in Brazil's north eastern state of Piauí. Diagnosis was based on clinical, serological and cultural findings. Four of 24 soil samples collected in and around the burrow of an armadillo yielded cultures of Coccidioides immitis, thus establishing the endemicity of that mould in the state of Piauí. A literature review revealed that C. immitis, aside from that state, is endemic in three other Brazilian states--Bahia, Ceará and Maranh?o. These four contiguous states have semi-arid regions where climatic conditions and their flora are similar to those that exist in C. immitis's endemic regions in North, Central and South America.  相似文献   

14.
The lagoon complex of Cispatá (old Sinú river delta) located at the Northwestern coast of the Colombian Caribbean, encloses one of the biggest mangrove areas in this region. This area has changed during the last 330 years because of several environmental and climatic causes, mainly changes in the position of the delta (Sinú River), which is the main freshwater source in this area, and sea level rise. We hypothesized that the climatic and geomorphologic dynamics has caused changes in the extension and composition of mangrove vegetation, especially during last 150 years. The dynamics of mangroves during the last 900 years was reconstructed based on the changes in the stratigraphy, pollen record, calcite concentrations (CaCO3) and C/N ratio, along two sediment cores from La Flotante and Navio lagoons, located in Cispatá complex. The age model was built based on lineal interpolation of 210Pb ages and changes in granulometry. Establishment and expansion of mangrove forests during the last 900 years were related to fluviomarine dynamics in the area and the lagoon formation. During the period encompassed between 1064 and 1762 A.D., the Mestizos spit was formed when marine conditions predominated in the surroundings of La Flotante Lagoon. At the site of Navío, a river dominated lagoon, terrigenous conditions dominated since 1830. Although the colonization of herbaceous pioneer vegetation started between 1142 and 1331 A.D., mangrove colonization only took place since 1717 A.D. Mangrove colonization was a result of the delta progradation. In 1849 A.D. the Sinú river delta migrated to the Cispatá bay. The eustatic sea level rise, the increase in river discharges and sedimentation rates produced the establishment of mangrove forests dominated by Rhizophora since 1849. Since 1900 a marine intrusion was recorded in both lagoons. In 1938, the migration of the delta toward its actual location in Tinajones gave place to the formation of the present lagoon system and to the expansion of mangrove forests, which reflects the balance between the high alluvial sediment input and the current sea level rise as has been recorded in similar ecosystems.  相似文献   

15.
In 2000, an outbreak of sylvatic yellow fever possibly occurred in gallery forests of the Grande river in the Paraná basin in the northwestern region of S?o Paulo state. The aim of this study was to obtain information on the bionomics of Haemagogus and other mosquitoes inside tree holes in that area. Eighteen open tree holes were sampled for immature specimens. Adults were collected twice a month in the forest in Santa Albertina county from July 2000 to June 2001. The seasonal frequency of fourth instars was obtained by the Williams geometric mean (Mw), while the adult frequency was estimated either by hourly arithmetic or the Williams' means. Cole's index was applied to evaluate larval inter-specific associations. Among the ten mosquito species identified, the most abundant was Aedes terrens Walker followed by Sabethes tridentatus Cerqueira and Haemagogus janthinomys Dyar. Larval and adult abundance of these species was higher in summer than in winter. Although larval abundance of Hg. janthinomys peaked in the rainy season, correlation with rainfall was not significant. Six groups of larval associations were distinguished, one of which the most positively stable. The Hg. janthinomys and Ae. terrens association was significant, and Limatus durhamii Theobald was the species with most negative associations.  相似文献   

16.
This study reports for the first time Edessa scabriventris St?l on Eugenia uniflora (Brazilian-cherry) and on Psidium guajava (guava) (Myrtaceae), fruit trees with economic value. Its geographic distribution is extended with records for the states of Alagoas (Maceió Municipality 35°45'11.16'W; 9°40'18.52'S) and Pará (Belém Municipality 48°28'14.65'W; 1°26'14.83'S), north-northeastern Brazil.  相似文献   

17.
An early stage of sex chromosome differentiation is reported to occur in the electric eel Eigenmannia virescens (Pisces, Sternopygidae) from populations of two tributaries of the Paraná river system (Brazil). Cytogenetic studies carried out in the two populations showed that the Mogi-Gua?u population is characterized by 2n = 38 chromosomes and undifferentiated sex chromosomes and the Tietê population presents 2n = 38 both for males and females and an XX:XY sex chromosome system. The X-chromosome is acrocentric, easily recognized by the presence of a conspicuous heterochromatin block in its distal portion; the Y-chromosome is probably one of the medium sized acrocentrics present in the male karyotype. BrdU induced R-bands of the two populations did not reveal any difference in the euchromatic regions of the chromosomes. AluI and HaeIII restriction enzyme digestion patterns and chromomycin A3 staining of the X-chromosome are presented. The possible role of heterochromatinization in the evolution of sex chromosomes in fish is discussed.  相似文献   

18.
This paper studies the migration pathways and ranges of a dominant detritivorous fish Prochilodus lineatus along pollution gradients in the Río de la Plata basin using multivariate analysis of biochemical and pollutant data. Biochemical composition (water, ash, lipids, proteins, carbohydrates, neutral lipids classes and fatty acids), aliphatic hydrocarbons (ALI), polychlorinated biphenyls (PCB), linear alkylbenzenes (LAB) and organochlorine pesticides (OClP) were determined in muscle samples of P. lineatus collected in Metropolitan Buenos Aires, the lower Paraná River (Paraná: 200-1000 km from Buenos Aires) and the middle Paraná and Paraguay Rivers (North: 1000-1400 km north). Biochemical variables and pollutants exhibited large variability [Lipids 1.1-89.5% wet mass; ALI 1.4-413; LABs not detectable (n.d.)-115.2; PCBs n.d.-27.9; OClPs n.d.-11.8 μg g(-1) dry mass], due to the contrast of Buenos Aires with North fish. Fish from Buenos Aires were fatty (lipids 24.7 ± 12.3% wet mass), enriched in 18 carbon fatty acids and severely contaminated (ALI 152.4 ± 72.3; LABs 65.1 ± 26.4; PCBs 15.2 ± 6.8; OClPs 1.8 ± 1.9 μg g(-1) dry mass mean ±S.D.). In contrast, fish from North were lean (4.1 ± 3.1% wet mass), enriched in long chain (>20 carbons) polyunsaturated fatty acids, with average one to two orders of magnitude lower pollutant levels (ALI 41.2 ± 51.9; PCBs 2.2 ± 3.5; LABs 8.8 ± 21.1; OClPs 0.67 ± 0.75 μg g(-1) dry mass mean ±S.D.). Paraná showed intermediate values in all variables, denoting the mixing of different fish stocks. Based on principal component analysis, 14 outliers from 60 North and Paraná samples (representing 26 from 108 individual fish) were identified as pertaining to the Buenos Aires group with very similar lipid and pollutant levels. Data suggest that P. lineatus migrates a highly variable distance, exceeding 800-1000 km in multiple spatial and temporal overlapping ranges. Chemometric analysis of biochemical and pollutant data effectively discriminates fish according to the chemical signature acquired by detritus feeding in pristine and contaminated urban or industrial areas.  相似文献   

19.
The genetic divergence among invasive and native populations of Plagioscion squamosissimus from four Neotropical hydrographic basins was assessed using the hypervariable domain of the mitochondrial DNA (mtDNA) control region. Plagioscion squamosissimus is native to the neighbouring hydrographic basins of the Parnaíba and Amazon Rivers, and the latter includes the Araguaia-Tocantins drainage, but it is invasive in other basins due to introductions. The mtDNA nucleotide polymorphism supported the hypothesis that the Amazon and Parnaíba populations constitute the same species and are separated into two independent evolutionary lineages. Absence of nucleotide polymorphism was observed within and among P. squamosissimus populations invasive to the uppper and middle Paraná River basins. Nucleotide divergence was null or low comparing the Paraná invasive populations with the populations native to the Parnaíba River basin, whereas it was significantly high compared to Tocantins populations. These results ascertain that P. squamosissimus populations invasive to the upper Paraná River basin and to the middle Paraná River basin downstream of the Itaipu dam are derived from the Parnaíba River basin. The genetic data presented are potentially useful to assist further studies on P. squamosissimus taxonomic and geographic distribution, development of ecological guidelines for managing populations invasive to the upper Paraná River basin and for preservation of native fish diversity.  相似文献   

20.
Benthic annelid communities were studied during a one-year period (August/95 to July/96) in two sectors of the beaches Engenho d'Agua and S?o Francisco, S?o Sebasti?o Channel (S?o Paulo, Brazil), where the substrate is composed by a mixture of sand and rock fragments. Abiotic parameters such as salinity of interstitial water and sediment properties were used to characterize the environment. The polychaetes were well represented in the two sectors and their distribution was related with sediment type. The density of individuals and the number of taxa was higher at S?o Francisco, while the diversity and the evenness were higher at Engenho d'Agua. This difference can be a consequence of organic enrichment caused by domestic input, and of the lower and more variable salinity at S?o Francisco. Due to these factors, the high density of opportunistic species, like Capitella capitata ssp., Scolelepis squamata, Laeonereis acuta and several oligochaetes, represented 75.5% of total abundance at this sector.  相似文献   

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