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1.
The Algarve Region (AR) in southern Portugal, which is an international tourist destination, has been considered an endemic region of zoonotic leishmaniasis caused by Leishmania infantum since the 1980s. In the present study, phlebotomine and canine surveys were conducted to identify sandfly blood meal sources and to update the occurrence of Leishmania infection in vectors and dogs. Four sandfly species were captured: Phlebotomus perniciosus, Phlebotomus ariasi, Phlebotomus sergenti and Sergentomyia minuta. In one P. perniciosus female, L. infantum DNA was detected. Blood meal tests showed that this species had no host preferences and was an opportunistic feeder. An overall canine leishmaniasis (CanL) seroprevalence of 16.06% was found; the seroprevalence was 3.88% in dogs housed in kennels and 40.63% in dogs that attended veterinary clinics. The simultaneous occurrence of dogs and P. perniciosus infected with L. infantum in the AR indicates that the region continues to be an endemic area for CanL. Our results reinforce the need for the systematic spatial distribution of phlebotomine populations and their Leishmania infection rates and the need to simultaneously perform pathogen monitoring in both invertebrate and vertebrate hosts to investigate the transmission, distribution and spreading of Leishmania infection.  相似文献   

2.
Abstract. In preparation for field trials of killed Leishmania major vaccine, natural infections with Leishmania promastigotes were monitored in Phlebotomine sandfly vectors from villages of Borkhar rural district, northeast of Isfahan in central Iran, where Lmajor zymodeme MON-26 (=LON-l) has been identified as causing zoonotic cutaneous leishmaniasis (ZCL). Sandflies were collected and dissected weekly, from burrows of rodent colonies, during the 'sandfly season', June-October 1991. Leptomonad infection rates were 12% of 26 Phlebotomus ansarii , 8% of 280 P.caucasicus , 11 % of 1042 P.papatasi and none of 126 Sergentomyia sintoni , being greatest during late August through September, coinciding with peak activity of the sandflies, 2–3 months before the highest incidence of ZCL human cases in November-December.  相似文献   

3.
Adult sandflies (Diptera: Psychodidae) of the genus Phlebotomus and of the subgenus Larroussius were collected with sticky traps from thirty-four localities in central and south-western Morocco. Four Larroussius species were present in this area, Phlebotomus perniciosus Newstead, being the most widespread and abundant species particularly in the mountainous area, was sympatric with the closely related species Phlebotomus longicuspis Nitzulescu. Only one male of P. perniciosus displayed the bifid copulatory valves characteristic of the species. All specimens showed copulatory valves curved at their apex. The number of coxite hairs is a taxonomical tool that differentiates this morph of P. perniciosus from P. longicuspis. Phlebotomus ariasi Tonnoir was collected from six mountainous stations. Phlebotomus mariae Rioux et al. was scarce; only five males were collected and were often associated with P. ariasi.  相似文献   

4.
Taxic responses may play a role in development of Leishmania in their phlebotomine sand fly vectors. They are possibly responsible for movement of the parasites towards the anterior regions of the gut, from where they would be transmitted to the vertebrate host. A methodology capable to distinguish chemotaxic from osmotaxic responses was described and used to characterise taxic responses in Leishmania promastigotes. These were able to respond to chemotaxic as well as to osmotaxic stimuli. Like bacteria, promastigotes were capable to undergo "adaptation," a phenomenon by which they stop responding to a continuos stimulus. A model capable to explain how a relatively small number of different receptors works to perceive gradients in chemotaxic responses was proposed. According to this model, these receptors possess low specificity and a wide range of affinities varying from high to low. A low specificity makes the same receptor able to bind to a large number of different but structurally related molecules and; a wide range of affinities (considering a population of receptors), implies that the number of receptors "occupied" by attractant molecules along a gradient would go growing step by step.  相似文献   

5.
Sand flies were infected with different species of promastigotes from reptiles and warm-blooded animals. Optimal doses of promastigotes were used which ensured the adaptation of Protozoa in the host's intestine. The infection with a mixed culture resulted in the death of most Sand flies: the mortality rate was the highest at the simultaneous introduction of two species and was some what lower at the subsequent infection. The survival of Sand flies infected with one species of leishmania decreased to the greatest extent if "incidental" for them strains of promastigotes were introduced: for Ph. papatasi -- cultures isolated from reptiles, for Sergentomyia arpaklensis -- those isolated from L. tropica major. Natural infection rate of the genera Phlebotomus and Sergentomyia with leishmania of different species agrees with laboratory data on the survival of sand flies. Ph. caucasicus and Ph. papatasi are infected, in general, with L. tropica major, S. arpaklensis -- with L. gymnodactyli.  相似文献   

6.
In a survey carried out during the summer in 2002 and 2003, in the canine and vulpine leishmaniasis focus of Arrabida, 665 phlebotomine sandflies were caught. 13.83% were P. ariasi, 58.65% P. pemiciosus, 0.45% P. sergenti and 27.07% S. minuta. Despite the low abundance, the finding of the three adults P. sergenti (two males in Aldeia Grande and one female in Quinta da Ramada) confirm the colonization of the Arrabida leishmaniasis focus by this species, which presence had been previously reported but thought accidental. The abundance of P. ariasi observed at this time is significantly different from that in previous years (Pires, 1984 and Fernandes pers. com., 1994). The occurrence of P. sergenti in this region, in association with the decrease in abundance of P. ariasi, may reflect an increased aridness of this region, a consequence of current climate and environmental changes.  相似文献   

7.
This study was carried out on the “Faro/Ancão” artificial reef (AR), located off Faro, deployed in May 2003. We aimed to characterise early macrobenthic community colonisation of two concrete AR groups located at different depths (16 m and 20 m depth) and to test the effect of reef structure on these communities. The non-colonial organisms were counted; barnacles and colonial species were quantified using biomass. Multivariate analyses indicated that early macrobenthic communities (6 months of immersion) were affected by depth, and that barnacles and colonial species were also affected by reef structure. Univariate analyses showed that the biomass of barnacles and colonial species was significantly different among reefs and layers of modules. Both AR groups were characterised by the species Balanus amphitrite, Gregariella subclavata, Musculus cf. subpictus, Paleanotus cf. bellis and Syllidia armata. Jassa marmorata and Bugula neritina were characteristic species at 16 m depth, particularly on the AR Upper layer of modules, whereas Anomia ephippium was particularly common at 20 m, especially on the Lower layer of modules.  相似文献   

8.
Summary

Palaemon longirostris and Crangon crangon larval and post-larval stages were collected intensively in two 24-h cycles during neap and spring tidal periods in a fixed station located in the mid-Mira estuary (southwest Portugal). In each case, on the previous day, horizontal distribution of larval stages was studied in a series of 20 stations from the mouth of the estuary to near freshwater. Horizontal distribution of the discrete instars of both species were similar, suggesting larval retention. Results from the 24-h cycles indicate a semilunar cycle of larval release activity, and an initial displacement of the larvae from the parental stock, as newly-hatched larvae concentrate in the surface layer of the water column on post-crepuscular ebbing tides. The sequence of larval stages tends to be progressively more dependent of the bottom layers, and the whole larval and post-larval development is accomplished within the estuarine boundaries. Larval release cycles, coupled with duration of development and progressive change in vertical position, induce mutual exclusion of different aged larvae, which may minimise cannibalistic behaviour and competition between larvae with different capabilities.  相似文献   

9.
A landlocked population of the anadromous clupeid Alosa alosa from Aguieira Reservoir in Portugal is described. The individuals are fast-growing, mature in their third year of life, live for 5+ years, and consequently spawn more than once.  相似文献   

10.
The use of rocky palaeoshore bioerosion analysis as a tool to solve stratigraphic and tectonic issues is beginning to bear fruits. The occurrence of an extensive intra-Miocene marine abrasion platform in southern Portugal at Oura (Albufeira) has been identified on the basis of bioerosion trace fossils analysis. The observed ichnodiversity is rather low, with bivalve boring Gastrochaenolites being dominant. Nevertheless, the ichnoassemblage may be assigned to the Entobia ichnofacies. The palaeoichnological study of the Oura hardground confirmed the existence of an important intra-Miocene stratigraphic gap (ca. 3 Ma hiatus), represented by a razor-sharp erosional contact that separates the two main Neogene units in the Algarvian region: the lower carbonate sequence of Lagos–Portimão Formation (Langhian/Serravallian) and the upper siliciclastic sequence of the Cacela Formation (Upper Tortonian).  相似文献   

11.
12.
Representativeness is a desirable property of conservation networks. In this paper an attempt is made to assess the efficiency of current conservation networks in Portugal in representing vertebrates (reptiles and amphibians) and plants (gymnosperms, pteridophytes and bryophytes). It was found that whilst the protected areas do not sample all species in the database they provide a better result than choosing areas at random. For the goal of maximizing representation of taxa per unit area hotspots and complementarity performed better. A pattern of over-representation of vertebrates in relation to lower plants was discovered among selected conservation areas in Portugal suggesting that charismatic organisms with large home ranges may not always be the most appropriate surrogates for biodiversity when representativeness is sought. When trying to fill the gaps in current protected areas with additional areas only complementarity performed better than choosing areas at random. Both rarity and richness hotspots gave worse results. Opportunistic administrative criteria such as supplementing the PAS with other conservation areas (CORINE Biotopes) without taking into account their contribution to a representation goal was nearly half as good as choosing areas at random. The results recall for the need of explicit goals and accountable methods in area selection for conservation and reinforce the role of complementarity for finding additional areas to protected areas when limited resources are available for ‘in situ’ conservation.  相似文献   

13.
Salivary gland proteins were studied in sandflies (Diptera: Psychodidae: Phlebotominae) by electrophoretic techniques. In Phlebotomus duboscqi Neveu-Lemaire the protein concentration was about 30 times higher in females than in males. SDS PAGE revealed eight major bands of 29-62 kDa in salivary gland extracts (SGE) from females, whereas only one band of 57kDa was detected in males. The number of protein components in SGE gradually increased with the age of females. In P. papatasi (Scopoli) the typical electrophoretic pattern was reached in 3-5 days after imago emergence, depending on the temperature at which females were maintained. All major protein components of the female SGE were present in the content of glands. Female SGE were compared in seven colonies of five Phlebotomus and Lutzomyia species; electrophoretic profiles distinguished between species and even between colonies of different geographical origin. In general, the highest variability of major protein components was observed in the 38-48kDa region. Four colonies of the subgenus Phlebotomus (P. duboscqi and P. papatasi) possessed common mobility polypeptides, the highest similarity was found between two colonies of P. papatasi. Other species tested significantly differed, specific prominent bands of 33, 35 and 38kDa were found in P. halepensis Theodor, P. perniciosus Newstead and Lutzomyia longipalpis (Lutz & Neiva), respectively. Glycoproteins in SGE of Lu. longipalpis and P. duboscqi females were identified and analysed using blotting with five lectin conjugates. Specific reaction of lectins ConA and WGA revealed the complex type of N-glycans in the 48 and 53-54kDa glycoproteins present in both species. Similar glycosylation was detected in species-specific bands of the 57-60 and 65-67 kDa in P. duboscqi and Lu. longipalpis, respectively. The high mannose type of glycosylation was found in the 20 and 39 kDa polypeptides of Lu. longipalpis and the 40-42 kDa polypeptides of P. duboscqi. Innate lectin activity specific for aminosugars was detected in SGE of P. duboscqi females using haemagglutination tests with rabbit erythrocytes.  相似文献   

14.
Summary Exometabolites (EXOM) of an Indian strain of Leishmania donovani promastigotes isolated from a chemically defined medium by ultrafiltration consisted of proteins, glycoproteins, lipid and lipophosphopolysaccharide (LPPS). LPPS of Mr 40-28 kDa in SDS-PAGE could be labelled metabolically with [32P]-phosphate and recovered in the aqueous phase of hot-phenol-water extraction of EXOM (PE-Aq) along with a glycoprotein of Mr 150-130 kDa (GP150-130) . These two molecules could be eluted from DE-52 column with 200 mM NaCI (D2). The 300 mM NaCl (D3) and 400 mM NaCl (D4) eluates from DE-52 column contained one unsaturated polar lipid component. The LPPS had Rf value of 0.65–0.75 in Thin Layer Chromatography (TLC) using saturated phenol water solvent system. EXOM revealed 15 bands in SDS-PAGE of which proteins of Mr 84, 66, 56, 50 and 29 kDa were prominent. When EXOM were fractionated through Con A — Sepharose column, the fraction eluted with -methyl-D-mannoside (Con A-E) had seven bands as revealed by SDS-PAGE of which 25, 16, 13 and 12 kDa glycoproteins were prominent.The antigens present in EXOM can be classified as slower anodic migrating and faster anodic migrating antigens as revealed by immunoelectrophoresis (IEP). The slower anodic migrating antigens, LPPS and GP150-130 recovered in PE-Aq and D2 did not cross-react with kala- azar patients' sera but cross-reacted with homologous anti-promastigote sera. Two faster anodic migrating antigens which could be recovered in organic phase of hot phenol extraction of EXOM (PE-O) and eluted in D3 and D4 and Con A-E, cross-reacted with kala-azar patients' sera. The antigens of both the classes were sensitive to periodic acid oxidation.  相似文献   

15.
16.
Abstract. The effectiveness of bednets and curtains (nylon mesh 64 per cm2) impregnated with deltamethrin at 26 mg a.i./m2 in reducing the biting nuisance caused by three phlebotomine sandfly species: Lutzomyia columbiana, Lu. lichyi and the predominant Lu. youngi (Diptera: Psychodidae), was evaluated at La Guaira, a rural settlement in Valle de Cauca near Cali, Colombia.
Pairs of volunteers collected sandflies under impregnated bednets, in rooms protected by impregnated curtains or in unprotected rooms in a randomized matched design. Collections were made in three houses per night on three consecutive nights, so that each house was sampled under each of the three treatments. This routine was repeated at 2-week intervals for 6 months. There was no significant difference between the overall numbers of sandflies collected in rooms with or without impregnated curtains. Only 0.14 sandflies/man-hour were caught on human bait under impregnated bednets, significantly fewer than the numbers collected on human bait outside the nets in the same room (1.91) or in unprotected rooms (3.29).
In a second set of experiments carried out in La Guaira and the neighbouring community of Jiguales, the effect of deltamethrin impregnation was evaluated by comparing numbers of sandflies collected on human bait under treated and untreated nets. Significantly fewer were collected under the impregnated nets (0.25 v. 0.69/man-hour). Wild-caught female Lu. youngi exposed to treated netting for 2 min in the laboratory all died with 24 h. The impact of deltamethrin-impregnated bednets was considered to be useful against Lu. youngi and other potential vectors of leishmaniasis in such communities.  相似文献   

17.
The variation in airborne pollen concentrationof the Braga region (Portugal) was studied inspringtime, during the flowering of Vitisvinifera. The data set was obtained for twoconsecutive years (1999 and 2000), using aCour-type sampler.During this period, thirty-six taxa wereobserved in a total of 3,200 pollengrains m-3 of air (CPA). The main pollentypes observed were Olea, Poaceaea,nd Castanea, representing 74% of thepollen spectrum.The airborne pollen concentration (CPA) wassignificantly correlated with certainmeteorological parameters. Pollen concentrationwas positively correlated with temperature andwind direction (East and Northeast) andnegatively correlated with rainfall and numberof rainy days.  相似文献   

18.
The male-killing spiroplasma strain NSRO causes an extremely female-biased sex ratio of the host, Drosophila melanogaster, as a result of selective death of male offspring during embryogenesis. The spiroplasma strain NSRO-A, a variant of NSRO, does not cause such symptoms. In an attempt to gain insights into the mechanism underlying the symbiont-induced reproductive phenotype, infection densities of the spiroplasmas in different tissues were monitored during host aging using a quantitative PCR technique. The density dynamics in the hemolymph were reminiscent of those in the whole body, whereas the density dynamics in the fat body, intestine and ovary were not. These results suggest that the majority of the spiroplasmas colonize and proliferate in the hemolymph of the host. In the hemolymph and whole body, the infection densities of NSRO were generally higher than those of NSRO-A, which may be related to the different reproductive phenotypes caused by the spiroplasmas.  相似文献   

19.
目的 通过对老年女性泌尿系统感染患者病原菌类型和耐药情况进行研究,为临床合理、安全、有效使用抗菌药物提供依据。方法 收集2014年9月至2017年7月在我院进行诊治的661例老年女性泌尿系统感染患者,对其清晨清洁中段尿进行细菌培养并进行耐药试验。结果 661例样本中共分离出病原菌255株,其中革兰阴性菌165株,占64.7%,以大肠埃希菌为主,构成比为45.5%;革兰阳性菌77株,占30.2%,以屎肠球菌为主,构成比为10.2%;真菌13株,占5.1%。G-菌中检出率排在前三的依次是大肠埃希菌、肺炎克雷伯菌、奇异变形杆菌。大肠埃希菌、肺炎克雷伯菌对氨苄西林、复方新诺明耐药性较高,奇异变形杆菌对头孢唑啉耐药性较高,三者均对亚胺培南敏感性较高。G+菌中检出率排在前三的依次是屎肠球菌、表皮葡萄球菌、粪肠球菌。三种病原菌对青霉素、氨苄西林、环丙沙星耐药性较高,对万古霉素、替考拉宁敏感性较高。结论 老年女性泌尿系统感染患者的病原菌多数为革兰阴性菌,且以大肠埃希菌为主,病原菌培养和耐药试验对于临床合理有效地使用抗菌药物具有重要的指导意义。  相似文献   

20.
A sample of 2013 meadow brown butterflies, Maniola jurtina , was obtained in the Algarve, southern Portugal, on behalf of E.B. Ford, the founder of ecological genetics. Variation in the meadow brown occupied Ford's attention for more than 40 years. Ford died in 1988; most of his collection had earlier been destroyed, but the meadow browns remained and became available for analysis. The butterflies were scored for spotting characters on both fore- and hindwings. The population is homogeneous over the entire area of the Algarve and there is no conclusive evidence of a difference between the two years of collection (1986 and 1987). It is probably also homogeneous with southern Iberia in general, an area unique in the western Palaearctic range of the species as it is characterized by a high spot average in males and a low spot average in females. Algarve butterflies differ markedly from those of the Canary Islands, where there is considerable inter-island heterogeneity, supporting the view that the Canary Island populations did not originate from southern Iberia. In the Algarve, many females aestivate and by September there is an essentially all-female population. These are low-spotted and differ significantly from females active in May and June at the start of the annual (one generation) flight season.  相似文献   

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