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1.
Natural mycoflora associated with fumonisins were analyzed in 150 samples of freshly harvested corn from Central-Southern, Central-Western and Northern regions of the State of Paraná, Brazil and correlated to climatic conditions. The corn samples were frequently contaminated with Fusarium sp.(98.7 to 100%) and Penicillium sp. (93 to 100%), when compared to Aspergillus sp. (not detected to 27.7%). The highest contamination with potentially mycotoxigenic fungi occurred in corn harvested in the Central-Western region, where total mould and yeast counts ranged from 5.5 × 103 to 5.2 × 106 CFU/g, with 98.7% contaminated byFusarium sp. and 93% by Penicillium sp. In this region F. moniliforme (F. verticillioides) was the predominant Fusariumsp., and was isolated in 85.9% of the samples. Aspergillus sp. was isolated from 27.7% samples. FB1 was detected in 100% of the samples (mean of 2.39 g/g) and FB2 in 97.7% (mean of 1.09 g/g). Fumonisins were also detected in all samples from Northern region, with mean of 4.56 g/g (FB1) and 2.20 g/g (FB2).Considering 1.0 g/g as the threshold, 72% of the corn samples from the Central-West and 92% from the North were contaminated with concentrations above this value, in contrast to a 18.5% contamination rate from Central-Southern samples. Between corn planting to harvesting season, the average maximum temperature and relative humidity were 26 °C and 77.1%(Central-Southern), 27 °C and 69% (Northern)and 29.9 °C and 89.1% (Central-Western).Therefore, the higher fumonisins contamination of corn from Northern region when compared to the Central-South were due to the differences in rainfall levels (92.8 mm in Central-Southern, 202 mm in Northern) during the month preceding harvest.This revised version was published online in October 2005 with corrections to the Cover Date.  相似文献   

2.
Abstract: Generally, natural environments have been transformed into small forest remnants, with the consequent habitat loss and species extinction. The North Paraná State is not an exception, since only 2 to 4% of the original ecosystem occurs in small fragments of Stational Semidecidual Forest. We studied the species richness and abundance of bats in two forest fragments from the Fazenda Congonhas, in Rancho Alegre city, Parana State, Brazil. Four samplings were undertaken in a legally protected native area (107.8 ha) and in a reforested area (11.8 ha) between April 2007 and March 2008. Samplings began at nightfall and lasted six hours,during two consecutive nights in each location. The individuals were captured using eight mist nets, with the same capture effort in both environments. A total of 397 individuals, 14 species and 10 genera were captured in the native area; while in the reforested area, 105 individuals, six species and four genera. Artibeus lituratus was the most common species in both fragments (n = 328, 65.3%), followed by Artibeus fimbriatus (n = 44, 8.8%) and Artibeus jamaicensis (n = 30, 6.0%). Other species including Platyrrhinus lineatus, Carollia perspicillata, Sturnira lilium, Chrotopterus aurintus, Desmodus rotundus, Michronycteris megalotis, Phyllostomus hastatus, Phyllostomus discolor, Myoti levis, Myotis nigricans and Lasiurus blossevillii, accounted for 19.9% of the captures. The native area presented higher values of species richness (S = 14) and diversity (H' = 1.4802) in comparison to the reforested area (S = 6, H '= 0.57015). The t-test evidenced a significant difference between diversity among the sites (t = 7.1075). Chao 1 index indicated that the sampling effort recorded approximately 78% from the total species richness for the native area and 75% for the reforested area. Therefore, the preservation of the forest fragment is essential since it provides habitat for a diverse community of bats. Forest management and reforestation actions may prevent drastic changes in the microclimate of neighboring areas within the forest fragment, and could allow the occupation of available niches in the area, by opportunistic and generalist species.  相似文献   

3.
Mean biomass (153-1) and production (P) of fish in two small tributaries of the Paraná River (Paraná, Brazil) were 61 kg ha–1 and 48 kg ha–1 yr–1 in the Caracu River and 29 kg ha–1 and 26 kg ha–1 yr–1 in the Agua do Rancho River, respectively. Matrix correlation analysis revealed high positive correlations of both 153-2 and P to maximum depth and hiding places and, at a lower level of significance, to mean depth, pH and oxygen level. Lower 153-3 and P values were found in the Agua do Rancho River, whose valley has retained a more natural character, rich canopy and scarcity of macrophytes, but also lower conductivity and nitrogen and phosphate levels than those in the Caracu River.Address for correspondence  相似文献   

4.
Summary  Field work in the state of Paraná, southern Brazil, has resulted in the discovery of a new epipetric filmy fern, Hymenophyllum filmenofilicum Christenh. & Schwartsb. (Hymenophyllaceae), which is described and illustrated here.  相似文献   

5.
The diagnosis of schistosomiasis is problematic in low-intensity transmission areas because parasitological methods lack sensitivity and molecular methods are neither widely available nor extensively validated. Helmintex is a method for isolating eggs from large faecal samples. We report preliminary results of a comparative evaluation of the Helmintex and Kato-Katz (KK) methods for the diagnosis of schistosomiasis in a low-intensity transmission area in Bandeirantes, Paraná, southern Brazil. Eggs were detected by both methods in seven patients, whereas only Helmintex yielded positive results in four individuals. The results confirm the previously demonstrated higher sensitivity of the Helmintex method compared with the KK method.  相似文献   

6.
The biological behaviour of 23 Trypanosoma cruzi isolates in Swiss mice was compared. Nineteen isolates were obtained from patients in the acute phase of Chagas disease (13), sylvatic reservoir hosts (Didelphis marsupialis) (3), and triatomine bugs (Rhodnius robustus) (3) from four regions of the State of Amazonas (AM). Four isolates were obtained from chronic chagasic patients in the State of Paraná (PR): three autochthones, and one allochthone from the State of Minas Gerais. Only one isolate was unable to infect the mice. The AM and PR isolates showed the largest number of significant differences from each other. The former had lower mean values in the pre-patent (5.4 days) and patent (4.6 days) periods (PP), with the parasitaemia (Pmax) reaching a peak of 9.9×10(4) blood trypomastigotes (BT)/mL of blood by the 7th day following inoculation. The AM isolates also had higher positivity to fresh-blood examination (FBE) (84.1%) compared to haemoculture (HC) (58.7%) and polymerase chain reaction (PCR) (33.3%), in addition to higher mortality (2.9%). The PR isolates had higher values for PP (18.5 days) and Pmax (99.9×10(4)BT/mL) as well as higher positivity to FBE (87.2%), HC (100%), and PCR (83.3%). The correlations between the biological behaviour of the T. cruzi isolates and the clinical and epidemiological characteristics of Chagas disease are discussed.  相似文献   

7.
Vulvovaginal candidiasis (VVC) is an infection caused by abnormal yeast growth in the mucosa of the female genital tract which is commonly diagnosed in gynecology. The aim of this study was to correlate the frequency of yeasts and their respective species in asymptomatic women with different clinical manifestation of VVC; evaluate possible relationships between number of fungus colonies and symptoms in this pathology. All patients who visited the laboratory within a period of five months, for routine examinations of vaginal secretion, independent of the presence or absence of symptoms of VVC were included in this study. Of these, women with immunodeficiency or with an infection of the genital tract by another agent were excluded. Candida albicans was the most frequently yeast isolated (60%). Among non-C. albicans yeasts, 61.5% were isolated of the asymptomatic women, 38.7% from patients with VVC and 11.1% of those from patients with RVVC. C. albicans was associated with symptoms of VVC and while, the presence of non-C. albicans yeasts with asymptomatic women. However, there was no association between the number of fungal colonies and symptoms.  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.
Cats are important in the epidemiology of Toxoplasma gondii because they are the only hosts that can excrete environmentally resistant oocysts. The prevalence of T. gondii was determined in 58 domestic cats from 51 homes from Santa Isabel do Ivai, Parana State, Brazil where a water-associated outbreak of acute toxoplasmosis had occurred in humans. Antibodies to T. gondii were found with the modified agglutination test in 49 of 58 (84.4%) cats at a serum dilution of 1:20. Tissues (brain, heart, and skeletal muscle) of 54 of these cats were bioassayed in T. gondii-free, laboratory-reared cats; T. gondii oocysts were excreted by 33 cats that were fed feline tissues. Brains from these 54 cats were bioassayed in mice; T. gondii was isolated from 7. Skeletal muscles and hearts of 15 cats were also bioassayed in mice; T. gondii was isolated from skeletal muscles of 9 and hearts of 13. The results indicate that T. gondii localizes in muscle tissue more than the brains of cats. In total there were 37 T. gondii isolates from 54 cats. Most isolates of T. gondii were virulent for mice. Genotyping of the 37 isolates of T. gondii, using the SAG2 locus, revealed that 15 isolates were type I and 22 were type III. The absence of type II genotype in cats in this study is consistent with the previous studies on T. gondii isolates from Brazil and is noteworthy because most T. gondii isolates from the United States are type II. These findings support the view that Brazilian and North American T. gondii isolates are genetically distinct. This is the first report of genotyping of T. gondii isolates from the domestic cat.  相似文献   

10.
11.
Knowledge of the effects of flooding on plant survival is relevant for the efficiency of management and conservation programs. Schinus terebinthifolius is a tree of economic and ecological importance that is common in northeast Brazil. Flooding tolerance and genetic variation were investigated in two riparian populations of S. terebinthifolius distributed along two different ecological regions of the Tibagi River basin. Flooding tolerance was evaluated through the investigation of young plants, submitted to different flooding intensities to examine the morphological and anatomical responses to this stress. The growth rate of S. terebinthifolius was not affected by flooding, but total submersion proved to be lethal for 100% of the plants. Morphological alterations such as hypertrophied lenticels were observed in both populations and lenticel openings were significantly higher in plants from one population. Genetic analysis using DNA samples obtained from both populations showed a moderate degree of genetic variation between populations (13.7%); most of the variation was found within populations (86.3%). These results show that for conservation purposes and management of degraded areas, both populations should be preserved and could be used in programs that intend to recompose riparian forests.  相似文献   

12.
Argyrotaenia sphaleropa (Meyrick) is associated with various fruit species in South America. This tortricid was first detected in citrus, Citrus sinensis (L.) Osbeck, in Brazil, in commercial groves in northern Paraná, during the 1994/95-crop season. The aim of this work was to study the biology of this lepidopteran under laboratory conditions (28 +/- 2 degrees C, 70 +/-10% UR, 14h photofase) using the citrus cultivar Pêra. Larvae obtained from egg masses collected in a commercial citrus grove in Rolandia, PR, were individually placed on citrus terminal leaves inside glass shell vials (8.5 x 2.5 cm) until adulthood. A male and a female moth were then transferred to acrylic cages (13 x 10 cm) containing inside a bouquet made with new citrus flush to serve as oviposition substrate. Adults were fed daily with a 10% honey solution. The biological parameters evaluated were duration of development of egg, larval and pupal stages; pupae weight; duration of pre-oviposition and oviposition periods, fecundity and longevity. The length of the egg to adult stage was around 36 days. The pre-oviposition period was almost two days, the oviposition period approximately ten days and the embryonary period around six days. Adult longevity was almost 15 days for females and nine days for males, and the lifetime fecundity was slightly over 180 eggs.  相似文献   

13.
Spatial and temporal variability in the concentration of saprophytic bacteria was investigated in surface waters of Paranaguá and Antonina bays.Seven points along a profile from the entrance of Paranaguá Bay to the innermost part of Antonina Bay, were sampled monthly from November 1985 to November 1986. Temperature, dissolved oxygen, pH and precipitation data were also measured.ZoBell 2216E culture medium was utilized with freshwater and 32% salinity water.Principal component analysis of biotic and abiotic data showed a gradient from the innermost bay to the baymouth bar with an increase in bacteria concentration at Antonina Bay. Significant variation was not observed among sampling stations at Paranaguá Bay, except for February 1986 when there was a homogeneous increase of bacteria throughout both bays in association with an increase in temperature and precipitation. There was also no strong variation of saprophyte numbers at sampling locations near Paranaguá city, despite domestic and harbour waste input.We conclude that the outer region of the estuary is highly influenced by the adjacent ocean and that the inner part has typical estuarine characteristics. The region may be considered little polluted.  相似文献   

14.
Fish species of the Zungaro genus (Siluriformes, Pimelodidae) are amongst the largest migratory fish in Latin America and have considerable economic importance for commercial fishing in Brazil. However, natural populations of this large catfish are experiencing a severe decline. There are significant taxonomical inconsistencies for this fish. Two geographically separated species of the fish were initially described, one endemic in the Amazon and another in the Paraná-Paraguay River basins. A taxonomic review had recently proposed that there is only one Zungaro species in Brazil, based on morphological data. We made a molecular study of Zungaro populations in an attempt to solve taxonomical inconsistencies and to analyze genetic diversity in natural populations of this genus. We analyzed two regions of the mitochondrial DNA (the control region and the ATPase 6 gene region) of individuals sampled from the Paraná-Paraguay River and Amazon River basins. Analyses based on p-distances and maximum likelihood phylogenetic models showed a genetic difference between populations corresponding to different species. Genetic differentiation between Zungaro populations was at the same level as that observed between other Siluriformes species, using the same DNA sequences. We conclude that Zungaro species of the Paraná-Paraguay River basin do not belong to the same species found in the Amazon basin. This finding has a significant implication for conservation of this fish, given that populations are disappearing at a high rate in the Paraná-Paraguay River basin, mainly due to impoundments.  相似文献   

15.
In Maputo (Southern Mozambique) and Bahia (Brazil), the most commonly used word to refer to namesakes is xará – a word of Amerindian origin. Although the institutions in question diverge considerably in each of these contexts, the two usages come together in that the sharing of a personal name establishes an alliance not only between the two persons involved but also among their relations. In this way, it is argued that the namesake institution is both supervening upon filiation and is a way of closing the local universe of relatedness upon itself. By superimposing a set of crossing ties, the namesake institution consolidates the entities at play and their relations. Nevertheless, much like filiation, upon which it is dependent, the namesake relation is one of co-responsibility and fusion between the partners, not of reciprocal responsibility. The latter is the product of the triangulation that such relations of alliance produce.  相似文献   

16.
The abundance of microcrustacean species recorded in plankton samples from the littoral and pelagic zones of the Upper Paran River, State of Mato Grosso do Sul, Brazil, was evaluated in relation to abiotic and biotic environmental factors. The cladocerans Bosminopsis deitersi and Bosmina hagmann i were most abundant. The presence or absence of aquatic macrophytes also influenced abundance and species composition. The true zooplankton species were most abundant at the pelagic stations, while species of Chydoridae and Macrothricidae contributed markedly to microcrustacean abundance and species richness at littoral stations. Species abundance was also strongly affected by water level variation. Microcrustaceans, mainly bosminids, were most abundant during low water. During high water, bosminids decreased in abundance while most other species increased. The higher variation of the environmental factors during high water probably explains the shift in abundance patterns. Changes in water level increased mixing of littoral and pelagic microcrustaceans between sampling stations.  相似文献   

17.
Uberlandia, MG, Brazil, underwent an accelerated process of urbanization with a population growth of 3,54% each year, higher than the national average. One of the problems emergent from urbanization is the use of different habitats for a great variety of insects. The objective of this study was to identify species of house-invading ants that occur in the urban area of Uberlandia. The occurrence of the house-invading species in regard to the time of urbanization, neighborhood infrastructure, age and maintenance of private houses was also assessed. The ants were collected using bait-traps in 120 residences from 12 neighborhoods which were put in three groups. Fourteen species of ants were catalogued, with Camponotus (Mayr), Monomorium (Mayr) and Tapinoma (Foerster) being the most frequent genera. Only Camponotus vittatus (Forel), Monomorium pharaonis (L.), Tapinoma melanocephalum (Fabricius) and Brachymyrmex sp. (Mayr) were collected in all three groups. The relation between the ants collected and the age and maintenance of the private houses showed that Paratrechina longicornis (Latreille) was most frequent (60%) in poorly preserved or precarious constructions. Whereas, C. vittatus and Camonotus melanoticus (Emery) occurred in all categories of maintenance. Overall, C. vittatus which had not been found in any previously published survey of urban ants, was the most frequent species in urban areas of the Cerrado.  相似文献   

18.
Within the frame of World Health Organisation (WHO) guidelines for the control of soil transmitted helminth (STH) infections, a baseline survey has been conducted in Queimadas Indian schoolchildren (group A) as compared with urban schoolchildren (group B), both located in Ortigueira, Paraná, Brazil, with the aim of orientating investigations. In an opportunistic study, the possible relationship between STH infection and nutritional status has been investigated. A total of 236 schoolchildren aged 5-15 years were enrolled, 100 in group A and 136 in group B. Prevalence of STH infections and heavy intensity infections were significantly higher in the group A (P < .001). A statistical significant correlation between stunting (Z-score < -2) and intensity of STH infections was noted. These results strongly suggested that mass treatment would be indicated in the indigenous community, possibly leading to improved nutritional status.  相似文献   

19.
The piranha, Serrasalmus marginatus is an abundant fish in the floodplains of the upper ParanáÝ river. We studied the stomach content of juvenile and adult piranhas over a year and determined the food items. Fragments of fish were the main diet components with age-dependent differences. There was no seasonal variation in the prey. This piranha is basically a diurnal predator with some differences in daily periods of feeding activity between juveniles and adults.  相似文献   

20.
Genetic variability in Hoplias malabaricus, from two localities in the upper Paraná River floodplain, was investigated by starch and polyacrylamide gel electrophoresis. A total of 52 specimens were analyzed for 14 enzymatic systems. Twenty-three gene loci of 13 enzymatic systems (AAT, ACP, ADH, GDH, G6PDH, GPI, IDH, LDH, MDH, MEP, PGM, PER, and SOD) were analyzed by starch gel electrophoresis (Penetrose-30). The EST system was analyzed by polyacrylamide gel electrophoresis, and one polymorphic locus was found (EST-1). Twenty-four loci were detected. The proportion of polymorphic loci was 37.5% in the lagoon and 33.3% in the river. Significant differences in allele frequencies of five loci were found between specimens from the two environments. Expected mean heterozygosity (H e = 0.14) is the same in the river and lagoon, however, Nei's genetic distance (D) between the population of the two locations was 0.049.  相似文献   

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