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1.
2.
Summary Specimens of the characid fish Brycon hilarii collected in dry and wet seasons in the River Juba, Tangará da Serra, State of Mato Grosso, Brazil, were surveyed for nematode parasites. Contracaecum sp. Type 1 and Type 2 larvae of Moravec, Kohn et Fernandes, 1993 were detected in the mesentery and liver, and Neocucullanus neocucullanus and Procamallanus (Spirocamallanus) inopinatus were observed in the intestine and pyloric caeca 75% of the nematodes were detected in the wet season. This is the first report of fish parasites from the River Juba and of the occurrence of Contracaecum larvae in B. hilarii.  相似文献   

3.
Summary Specimens of Micromesistius poutassou (n=238) obtained in a fish market of Oporto, Portugal, were examined for the presence of larval anisakids. Anisakis sp. L3 larvae (prevalence = 77.7 %; mean intensity = 5.8; mean abundance = 4.5) and Hysterothylacium sp. L3 larvae (prevalence = 5 %; mean intensity = 4.1; mean abundance = 0.2) were found in body cavity, mesenteries, liver and muscles. The Anisakis sp. intensity and abundance were significantly related to the host body length. The percentage of Anisakis sp. in muscle was inversely related to the host length.  相似文献   

4.
Bioassays and biochemical assays were conducted on eight Trinidadian strains of Aedes aegypti larvae to determine the involvement of biochemical mechanisms in resistance to insecticides. Larval strains were assayed to dichlorodiphenyltrichloroethane (DDT), bendiocarb, temephos and permethrin, using the Centers for Disease Control and Prevention (CDC) time-mortality bioassay method. A Resistance Threshold (RT) was calculated for each insecticide in relation to the CAREC reference susceptible Ae. aegypti strain and larval strains with <80% mortality were considered to be resistant. Biochemical assays were performed to determine the activities of nonspecific esterases (α- and β-), PNPA-esterases, mixed function oxidases (MFO), glutathione-S-transferases (GST) and acetylcholinesterase (AChE) enzymes which are involved in insecticide resistance in mosquitoes. Enzyme profiles of each strain were compared with those of the CAREC reference susceptible strain by Kruskal–Wallis and Dunn's multiple comparison tests (p < 0.05). The CAREC 99th percentile was calculated for each enzyme and the percentage of individuals with enzyme activities above that of the CAREC 99th percentile was calculated. Activities were classified as unaltered (<50%), incipiently altered (15–50%) or altered (>50%) for each strain.The established RTs for permethrin and bendiocarb were 30 and 75 min, respectively; and 120 min for DDT and temephos. All strains were resistant to DDT (1.00–40.25% mortality) and temephos (11.50–74.50% mortality) while six strains were resistant to bendiocarb (51.50–78.50% mortality) and five to permethrin (6.50–42.50% mortality). Biochemical assays revealed that the median activity levels for all enzymes varied significantly (p < 0.05). The Curepe strain had incipiently altered levels of α-esterase while the other seven strains had altered activity with five of them registering 100%. The St Clair strain showed altered activity levels of β-esterase while three strains had incipiently altered levels. The majority of strains had altered activity of MFO enzymes but only the St Clair strain showed altered activity of GST. PNPA-esterases activity was unaltered in all strains and only the Haleland Park strain showed altered remaining AChE activity in the presence of propoxur.Elevated levels of enzymes (incipiently altered or altered), except in the case of PNPA-esterases, show that biochemical resistance may play an important role in the manifestation of insecticide resistance in Trinidadian populations of Ae. aegypti. It is therefore important for insecticide resistance surveillance to be ongoing as the detection of resistance before it spreads throughout an entire population makes it possible for early intervention.  相似文献   

5.
Anisakid nematodes have been found in a variety of marine fishes throughout the world and they are known to cause anisakiasis in human hosts. The present study investigated the prevalence of potentially zoonotic anisakid larvae in spotted mackerel caught from Taiwanese waters where fish represents an important food sources. Anisakis third-stage larvae (L3, n = 502) were isolated from 250 spotted mackerel Scomber australasicus. Anisakis L3 larvae were divided morphologically into two types, Anisakis type I larvae had a longer ventriculus and mucron while type II larvae had a shorter ventriculus and no mucron. Anisakis species were identified by polymerase chain reaction-restriction fragment length polymorphism (PCR–RFLP) of the internal transcribed spacer (ITS) regions of ribosomal DNA and direct sequencing. A simple molecular taxonomic key, utilizing RFLP by two restriction enzymes HinfI and HhaI, enabled the differentiation of the genus Anisakis. The prevalence, mean intensity and mean abundance of Anisakis nematodes recorded for the total specimens were 72.8%, 2.8 (1–15) and 2.0 (0–15), respectively. Anisakis pegreffii was determined to be the dominant species (prevalence = 57.2%) and important agent of human anisakiasis. A recombinant genotype (Anisakis simplex sensu stricto × A. pegreffii) was identified as the subdominant species (25.3%) followed by Anisakis typica (10%), Anisakis physeteris (4.0%), Anisakis paggiae (3.0%) and Anisakis brevispiculata (0.5%). The topology of the maximum likelihood and neighbor-joining trees show two well supported clades: one includes the species of A. pegreffii and the other includes A. paggiae, A. physeteris and A. brevispiculata, while A. typica has basal position to all other Anisakis spp. analyzed. This study advances our knowledge of the prevalence of different Anisakis spp. in the spotted mackerel from Taiwanese waters, which is helpful for monitoring the fish populations throughout a diverse array of aquatic ecosystems. More importantly, we provide the concise characterization of multiple Anisakis spp. by PCR–RFLP, which could also be applicable for the rapid diagnosis of human anisakiasis.  相似文献   

6.
Summary  Two species of pinworms (Enterobiinae) were collected from fresh faeces of semi-wild orangutans Pongo abelii Lesson living in northern Sumatra (Indonesia). The female of Enterobius (Enterobius) buckleyi Sandosham, 1950 is redescribed. Lemuricola (Protenterobius) pongoi n. sp. is described on the basis of females (no males are available) and distinguished from L. (P.) nycticebi (Baylis, 1928) by cephalic and mouth morphology (head and teeth superstructures), body (9.85–15.46 mm) and tail (2.34–2.95 mm) length, smaller eggs (48–56 x 22–28 μm), longer vulva distance from anterior extremity (2.05–3.09 mm) and other features. Characteristic is the total body length/oesophagus length ratio (1: 15.3–22.0). Both nematode species were studied using scanning electron microscopy for the first time.  相似文献   

7.
Normal somatic cells have a finite replicative capacity. With each cell division, telomeres (the physical ends of linear chromosomes) progressively shorten until they reach a critical length, at which point the cells enter replicative senescence. Some cells maintain telomere length by the action of the telomerase enzyme. The bristlecone pine, Pinus longaeva, is the oldest known living eukaryotic organism, with the oldest on record turning 4770 years old in 2005. To determine what changes occur, if any, in telomere length and telomerase activity with age, and what roles, if any, telomere length and telomerase activity may play in contributing to the increased life-span and longevity of P. longaeva with age, as well as in other tree species of various life-spans, we undertook a detailed investigation of telomere length and telomerase activity in such trees. The results from this study support the hypothesis that both increased telomere length and telomerase activity may directly/indirectly contribute to the increased life-span and longevity evident in long-lived pine trees (2000–5000 year life-spans) compared to medium-lived (400–500 year life-span) and short-lived (100–200 year life-span) pine trees, as well as in P. longaeva with age.  相似文献   

8.
This study was conducted to determine the effects of increased water temperatures on the development of Aedes aegypti immatures under laboratory conditions in Trinidad, West Indies using temperature regulated water baths to cover a range of temperatures from 24–25 °C to 34–35 °C at a relative humidity of 80%. Two experiments were designed: (1) at constant temperature regimens and (2) under diurnal temperature regimens ranging from 24–25 °C to 34–35 °C. At 24–25 °C egg hatching success was 98% at 48 h, however at 34–35 °C egg hatching rates declined to 1.6% after 48 h. Ae. aegypti larvae reared under constant temperature regimens showed pupation on day 4 with highest pupation occurring at 30 °C (78.4%) However, under diurnal temperature regimens, pupation began on day 4 but only at the higher temperatures of 30–35 °C. Under diurnal temperature regimens ranging from 24 °C to 35 °C significantly more females emerged at higher temperatures, than males. In contrast, at constant temperatures of 24–35 °C no significant difference in M/F ratios were observed. The body size of Ae. aegypti reared at constant temperature regimens was significantly larger than males and females larvae reared under diurnal temperature regimens of 25–30 °C. The results of this study are discussed in the context of changing or increasing water temperatures, seasonal changes in vector populations and vector competence. Using these key factors control strategies are recommended to manage vector populations as expected increases in temperatures impact the Caribbean region.  相似文献   

9.
Summary The genetic identification and distribution of Anisakis larvae in Indonesia is described. 110 Auxis rochei rochei and 45 Decapterus russellii were sampled from fish markets in North (Anturan) and South (Kedonganan) Bali. Nematode larvae from A. rochei rochei, Caesio cuning and Epinephelus areolatus from Kedonganan and from Coryphaena hippurus from Pelabuhan Ratu, South Java, were identified using sequence analysis of the internal transcribed spacers (ITS-1, ITS-2) and 5.8S region of rDNA. The larvae belonged to Anisakis typica with an identical sequence to this species from the spinner dolphin (Stenella longirostris) from Brazil, and to 2 further genotypes that differed from that sequence by 0.24–0.47 %. A. typica occurred in the migratory A. rochei rochei and C. hippurus, while Anisakis sp. 1 and 2 were isolated from the same fish species and the non-migratory C. cuning and E. areolatus. The latter genotype is distinguishable by 4 positions in the ITS-1 region (1.1 %), a genetic distance that indicates the presence of an Indonesian A. typica sibling species. The musculature infection in A. rochei rochei was low (2.5 %), indicating no major risk for the fish consumers. The much higher A. typica infection of fish intermediate hosts in the northern Bali coast is suggested to be dependent on the large dolphin population (nematode final hosts) in the waters off Lovina Beach (North Bali).  相似文献   

10.
Mosquitoes transmit serious human diseases, causing millions of deaths every year. Use of synthetic insecticides to control vector mosquitoes has caused physiological resistance and adverse environmental effects in addition to high operational cost. Insecticides of synthesized natural products for vector control have been a priority in this area. In this study, larvicidal activity of synthesized silver nanoparticles (AgNPs) utilizing aqueous extract from Eclipta prostrata, a member of the Asteraceae was investigated against fourth instar larvae of filariasis vector, Culex quinquefasciatus say and malaria vector, Anopheles subpictus Grassi (Diptera: Culicidae). The synthesized AgNPs characterized by UV–vis spectrum, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and X-ray diffraction (XRD). SEM analyses of the synthesized AgNPs were clearly distinguishable measured 35–60 nm in size. Larvae were exposed to varying concentrations of aqueous extract of synthesized AgNPs for 24 h. The maximum efficacy was observed in crude aqueous, and synthesized AgNPs against C. quinquefasciatus (LC50 = 27.49 and 4.56 mg/L; LC90 = 70.38 and 13.14 mg/L), and against A. subpictus (LC50 = 27.85 and 5.14 mg/L; LC90 = 71.45 and 25.68 mg/L) respectively. The chi-square value were significant at p < 0.05 level. These results suggest that the synthesized AgNPs have the potential to be used as an ideal eco-friendly approach for the control of the Culex tritaeniorhynchus and A. subpictus. This method is considered as a new approach to control vectors. Therefore, this study provides first report on the mosquito larvicidal activity of synthesized AgNPs against vectors.  相似文献   

11.
Amodiaquine (AQ) is currently being used as a partner drug in combination with artesunate for treatment of uncomplicated malaria in most endemic countries of Africa. In the absence of molecular markers of artemisinin resistance, molecular markers of resistance to AQ may be useful for monitoring the development and spread of parasites resistance to Artesunate–Amodiaquine combination. This study was designed to assess the potential role of polymorphisms on pfcrt and pfmdr1 genes and parasite in vitro susceptibility for epidemiological surveillance of amodiaquine resistance in Plasmodium falciparum. The modified schizont inhibition assay was used to determine in vitro susceptibility profiles of 98 patients’ isolates of P. falciparum to amodiaquine. Polymorphisms on parasites pfcrt and pfmdr1 genes were determined with nested PCR followed by sequencing.The geometric mean (GM) of AQ 50% inhibitory concentration (IC-50) in the 97 P. falciparum isolates was 20.48 nM (95% CI 16.53–25.36 nM). Based on the cut-off value for AQ in vitro susceptibility, 87% (84) of the P. falciparum isolates were sensitive to AQ (GM IC-50 = 16.32 nM; 95%CI 13.3–20.04 nM) while 13% were resistant to AQ in vitro (GM IC-50 = 88.73 nM; 95%CI 69.67–113.0 nM). Molecular analysis showed presence of mutant CVIET pfcrt haplotype, mutant pfmdr1Tyr86 allele and the double mutant CVIET pfcrt haplotype + pfmdr1Tyr86 in 72%, 49% and 35%, respectively. The GM IC-50 of isolates harboring the wild-type pfcrt CVMNK haplotype + pfmdr1Asn86 allele (3.93 nM; 95%CI 1.82–8.46 nM) was significantly lower (p = 0.001) than those isolates harboring the double mutant pfcrt CVIET haplotype + pfmdr1Tyr86 allele (50.40 nM; 95%CI 40.17–63.24 nM).Results from this study suggest that polymorphisms in pfcrt and pfmdr1 genes are important for AQ resistance and therefore may be useful for epidemiological surveillance of P. falciparum resistance to AQ.  相似文献   

12.
Marked spatiotemporal variabilities in mosquito infection of arboviruses require adaptive strategies for determining optimal field-sampling timeframes, pool screening, and data analyses. In particular, the error distribution and aggregation patterns of adult arboviral mosquitoes can vary significantly by species, which can statistically bias analyses of spatiotemporal-sampled predictor variables generating misinterpretation of prolific habitat surveillance locations. Currently, there is a lack of reliable and consistent measures of risk exposure based on field-sampled georeferenced explanatory covariates which can compromise quantitative predictions generated from arboviral mosquito surveillance models for implementing larval control strategies targeting productive habitats. In this research we used spatial statistics and QuickBird visible and near-infra-red data for determining trapping sites that were related to Culex quinquefasciatus and Aedes albopictus species abundance and distribution in Birmingham, Alabama. Initially, a Land Use Land Cover (LULC) model was constructed from multiple spatiotemporal-sampled georeferenced predictors and the QuickBird data. A Poisson regression model with a non-homogenous, gamma-distributed mean then decomposed the data into positive and negative spatial filter eigenvectors. An autoregressive process in the error term then was used to derive the sample distribution of the Moran's I statistic for determining latent autocorrelation components in the model. Spatial filter algorithms established means, variances, distributional functions, and pairwise correlations for the predictor variables. In doing so, the eigenfunction spatial filter quantified the residual autocorrelation error in the mean response term of the model as a linear combination of various distinct Cx. quinquefasciatus and Ae. albopictus habitat map patterns. The analyses revealed 18–27% redundant information in the data. Prolific habitats of Cx. quinquefasciatus and Ae. albopictus can be accurately spatially targeted based on georeferenced field-sampled count data using QuickBird data, LULC explanatory covariates, robust negative binomial regression estimates and space–time eigenfunctions.  相似文献   

13.
In this work, we examined the production of infective zoospores of Lagenidium giganteum in four culture media, and the larvicidal activity of the cultures was determined against Aedes aegypti larvae, as well as the effect of polymer encapsulation. Medium containing sunflower seed extract showed the greatest production of zoospores, 5.92 × 106 zoospores/ml after six days of fermentation at 25 ± 2 °C and 150 rpm shaking. This culture tested against A. aegypti 1st stage larvae caused different mortality rates at 24, 48 and 72 h posttreatment. The LC50 obtained was 43.9, 41.1 and 42.9 μl of total culture/ml, at 24, 48 and 72 h posttreatment respectively, while the culture grown in medium with soybean meal showed 3–5 times higher LC50 values. Finally, the total culture including mycelium, zoospores and presporangia formulated with 2.5% pectin showed significantly higher mortality rates, around 100% more than the unformulated culture, whose values were from 40 to 1% at 3, 6, 9, and 12 d posttreatment in the bioassays carried out in the laboratory to determine residual activity.  相似文献   

14.
Summary  In 2005, root and soil samples were collected from the rhizosphere of Viburnum sp. plants in the yard of a house in Kifissia, Attica, Greece. The plants showed symptoms of yellowing and declining and all were dead within, approximately, one year. The roots were infected with the fungus Rosellinia necatrix. Several specimens of a ring nematode were recovered from soil and identified as Mesocriconema xenoplax based on morphological and morphometrical analysis of females. The nematode had been previously found on grapevines in Samos and Crete islands. This is the first report of M. xenoplax in Greece and the first record of Viburnum sp. as a host for this ring nematode. Additional information regarding distribution of this nematode in Greece is needed.  相似文献   

15.

Background

Recent genome-wide association studies have identified over 40 candidate genes contributing to ulcerative colitis susceptibility. The goal of this study was to test the reported ulcerative colitis susceptibility genes including FCGR2A, SLC26A3, JAK2 and HNF4A in Korean patients with ulcerative colitis and Crohn's disease.

Methods

Five single nucleotide polymorphisms from 4 loci including FCGR2A, SLC26A3, JAK2 and HNF4A were genotyped in 661patients with ulcerative colitis, 642 patients with Crohn's disease and 601 healthy controls.

Results

Statistically significant associations with ulcerative colitis were found at FCGR2A (rs1801274, p = 2.3 × 10−4, OR = 0.70 (95% CI = 0.57–0.84) under the allelic model), the JAK2 locus (rs10975003, p = 6.7 × 10−4, OR = 1.43 (95% CI = 1.16–1.77) under the allelic model) and HNF4A (rs6017342, p = 0.002, OR = 0.66 (95% CI = 0.51–0.85) under the allelic model). The association of FCGR2A was much stronger in female patients with ulcerative colitis (p = 5.7 × 10−6) than in males (p = 0.50). Except rs10975003 from the JAK2 locus, none showed positive association with Crohn's disease.

Conclusions

Our data suggest that FCGR2A, JAK2 or HNF4A variants play a role in the pathogenesis of ulcerative colitis in Koreans.  相似文献   

16.
The nematode Caenorhabditis elegans responds to flavonoid-rich diets with improved health and longevity. The precise mechanism(s) responsible for this remains to be identified, but is believed to be linked to the highly antioxidative properties of flavonoids. This study provides a dissection of lifespan modulation by the flavonoid quercetin. In detail, quercetin was shown not to act as a simple antimicrobial agent or exclusively via radical scavenging capacities. Likewise, lifespan extension had no effect on reproduction and body length. Furthermore, neither a caloric restriction mimetic nor a sirtuin (sir-2.1) dependence was identified as a likely mode of action. However, four genes were pinpointed to be required for the quercetin derived lifespan extension, namely age-1, daf-2, unc-43 and sek-1. The latter two have, to date, not been linked to quercetin-mediated lifespan extension. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

17.
Cratylia mollis is a natural forage plant from the Northeast of Brazil. C. mollis seed lectin (Cramoll) containing molecular forms 1 and 4 (Cramoll 1,4) has shown anti-inflammatory and wound-healing activities. This work analyzed the effect of Cramoll 1,4 on experimental schistosomiasis in mice. Experimental groups (n = 15/group) were composed of female albino Swiss mice, which were subcutaneously and caudally infected with Schistosoma mansoni (BH strain, 100 cercariae/mouse) and were treated with an intraperitoneal dose after infection as follows: (1) Cramoll 1,4 (50 mg kg−1 single dose – after 40 days of infection), (2) Cramoll 1,4 (7 mg kg−1 daily dose – for 7 days after infection) and control (untreated mice). Mice were sacrificed 8 weeks after infection and adult worms were recovered from the portal-hepatic system. Livers were fixed in 10% (v/v) formaldehyde/0.15 M NaCl and tissue sections were processed for haematoxilin and Masson's trichrome stainings. Mice infected subcutaneously harboured no or very few worms and hence the effect of Cramoll 1,4 could not be assessed. Results (P ≤ 0.05) were obtained with Cramoll 1,4 using the two treatments, with reduction of: egg excretion (79 and 80%), adult worm recovery (71 and 79%) and liver granulomas (40 and 73.5%) in relation to control. This study showed the potential anti-helminthic activity of Cramoll 1,4 when tested against Schistosomiasis mansoni infection in mice.  相似文献   

18.
Summary  Data on prevalence and current distribution of the cestode Nippotaenia mogurndae Yamaguti and Miyata, 1940 (Nippotaeniidea) in Slovakia, are provided. A total of 163 fish from 8 localities of different types in the Tisa River basin were infected with N. mogurndae. The mean intensity of infection was 1.8 with a maximum of 5 tapeworms. The expansion of the distribution of the cestode corresponds well with the spreading of its host, the invasive fish Amur sleeper Perccottus glenii Dybowski, 1877. The Spearmann correlation coefficient was used to test the relationship between the intensity of infection and standard length of the fish (r = 0.36; n = 163; P < 0.05), condition coefficient of the fish (r = 0.22; n = 115; P < 0.05) and season (r = −0.37; n = 355; P < 0.05). A significant correlation was confirmed for each pair of variables. There is a statistically significant difference between the prevalence of the cestode in two functional size groups (t = 3.28; n = 163; P < 0.05). The prevalence of the cestode increased with the standard length of fish. The potential risk of further expansion of N. mogurndae to other countries is discussed.  相似文献   

19.

Background

In Japan, a major type of home-related hypersensitivity pneumonitis (HP) is summer-type HP, which is caused by Trichosporon asahii (T. asahii) or Trichosporon mucoides. Some patients with home-related HP test negative for antibodies against Trichosporon; yet, a causative mold antigen cannot be identified.

Methods

We analyzed 19 patients with home-related HP, 8 healthy volunteers, and 35 patients with other diseases. We extracted DNA from cell pellets of bronchoalveolar lavage fluid (BALF), amplified the DNA by PCR using Trichosporon-specific primers or other fungus-specific primers, and cloned as well as sequenced the PCR amplicon. Other primers used were specific for Acremonium chrysogenum, Aspergillus fumigatus, Aspergillus niger, Fusarium napiforme, Humicola fuscoatra, Penicillium corylophilum, and Pezizia domiciliana.

Results

We detected Trichosporon DNA (n = 17) and F. napiforme DNA (n = 2) by PCR in 19 patients with home-related HP; however, these species were not identified in healthy volunteers. After sequencing of the PCR amplicon for Trichosporon species, we identified T. asahii (n = 11), Trichosporon japonicum (n = 1), and Cryptococcus uzbekistanesis (n = 4).

Conclusion

We could detect fungal DNA in BALF cell pellets from patients with home-related HP. These data suggest that this method might be useful to detect antigens responsible for home-related HP.  相似文献   

20.
Summary Eight taxons of nematode parasites were recovered from three species of charadriid shorebirds (Charadriiformes) from Slovakia: common ringed plover — Charadrius hiaticula (L.) (No=9), little ringed plover — Charadrius dubius Scop., 1786 (No=56) and golden plover — Pluvialis apricaria (L.)(No=14). New host record (Ch.dubius) were registered for Tetrameres (Tetrameres) nouveli (Seurat, 1914), described as so far unknown Tetrameres (T.) nouveli bodrogensis n. ssp. New data on Victorocara charadrii Belopolskaja, 1953 have been pointed out. Besides the taxons mentioned above, the following species were registered: Eucoleus contorta, Eucoleus obtusiuscula and in Slovakia so far not described Capillaria limicolae, Tetrameres (T.) sp., Capillaridae gen. sp. and Anisakidae gen. sp.  相似文献   

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