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In order to better understand the epidemiology of ovine toxoplasmosis in Sardinia, a serological survey was carried out on 22 flocks with no fertility problems. In total 1043 sera (9% of the 11,382 sheep raised in the flocks) were examined by means of a commercial ELISA kit. To verify the performance of ELISA test, 160 selected sera were tested again with a gold standard test (IFAT). Performance of the commercial ELISA kit was summarised in terms of Sensitivity (SE), Specificity (SP), positive and negative Likelihood Ratios (LR+; LR-). The overall seroprevalence with ELISA test was recorded as 51.3%. It was generally increasing according to age and was significantly lower in animals younger than one year (with the exception of < 1 month old lambs). This survey provided data on the current Toxoplasma gondii sheep seroprevalence in Sardinia, confirmed a still high parasite pressure and pointed out that consumption of raw or undercooked ovine meat can be considered a potential risk factor for humans.  相似文献   

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Molara is a small island belonging to the Marine protected Area Tavolara—Punta Coda Cavallo, in Sardinia. During 2006–2007, a bio-monitoring program reported a strong presence of the black rat, Rattus rattus, on Molara island. Rat predation has detrimentally affected the unique biodiversity of this island, thus, in 2008 an eradication campaign was conducted. Our eradication protocol included a pre-eradication genetic investigation, using 8 microsatellite loci, on a rat population of Molara as well as on neighbour islands within the Marine Protected Area (MPA). The main goal of this genetic investigation was to establish the correct borders of the eradication unit of Molara island. As several recent eradication campaigns have been unsuccessful, due to incomplete and unstable eradication, we also aimed to assess possible hidden sources of reinvasion. Specimens were also collected during post- eradication monitoring on Molara for genetic screening to establish their origin, and thus validate the effectiveness of our eradication campaign. According to our genetic analysis, within the MPA there are four different eradication units, corresponding to the islands of Molara, Tavolara, Piana and to the Sardinia mainland. Gene flow among these four units is more or less absent. The assignment and clustering tests performed on pre and post-eradication samples seem to indicate that the population of Sardinia mainland is a possible source of re-invasion for the Piana and Molara populations.  相似文献   

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Butterfly, spider, and plant species richness and diversity were investigated in five different land-use types in Sardinia. In 16 one-hectare plots we measured a set of 15 environmental variables to detect the most important factors determining patterns of variation in species richness, particularly endemicity. The studied land-use types encompassed homogeneous and heterogeneous shrublands, shrublands with tree-overstorey, Quercus forest and agricultural land. A total of 30 butterfly species, among which 10 endemics, and 50 spider (morpho)species, were recorded. Butterfly and spider community composition differed according to land-use type. The main environmental factors determining diversity patterns in butterflies were the presence of flowers and trees. Spiders reacted mainly to habitat heterogeneity and land-use type. Traditional land-use did not have adverse effects on the diversity of butterflies, spiders, or plants. The number of endemic butterfly species per treatment increased with total species richness and altitude. Butterfly and spider richness did not co-vary across the five land-use types. Butterflies were, however, positively associated with plant species richness and elevation, whereas spiders were not. Conclusively, butterflies did not appear to be good indicators for spider diversity and species richness at the studied sites.  相似文献   

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Summary A sample of healthy unrelated individuals (882 from Continental Italy and Sicily, and 139 from Sardinia) were typed for HLA and Bf polymorphisms. Bf gene frequencies in Continental Italy and Sicily show an intermediate position among European populations, with Lapps on one side and Basques on the other side; while a very peculiar pattern is observed among Sardinians, with an impressive similarity with French Basques and with the highest F1 gene frequency so far observed. The HLA: Bf gametic associations in Italy and Sardinia are also reported, which confirm the different ethnic background of these populations.This work was supported by Centro di Immunogenetica ed Istocompatibilità, C.N.R., Torino, Italy and by a grant of Ministero Pubblica Istruzione (M.P.I., Cap. 8551/1980).  相似文献   

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Over the last ten years the population of the Mediterranean island of Sardinia has been object of numerous studies in the fields of anthropology and population genetics. Its insularity, central position in the Mediterranean area and rich historical past have made the island a veritable laboratory for the study and understanding of those interacting evolutionary mechanisms which determine a population's genetic structure. Indeed, from work performed at different levels on genetic structure analysis there emerges an extremely complex picture of the relationships between Sardinian and other Italian and Mediterranean populations, but also of relationships within the Sardinian population itself The diversification from Mediterranean and Italian populations can be explained by Sardinia's historical and demographic past. Internal heterogeneity can be attributed, in part, to strict isolation and the accompanying high levels of endogamy and inbreeding, and in part to the endemic presence of malaria which exerted a strong selective pressure on some characteristics; determining, for example, the differentiation between the plains and the mountain areas. Finally, an influence on Sardinia's biological history not to be neglected could be attributed to the demographic events, which triggered off phenomena of genetic drift and to cultural factors.  相似文献   

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The availability of highly polymorphic markers permits testing whether complex traits and diseases result from genomic interactions between nonallelic normal variants at separate loci. Such variants may be identified by deviations from the expected distributions of alleles at a high number of polymorphic loci, when individuals with the phenotype of interest are compared to normal controls of the same breeding unit, provided that both groups share the same remote ancestry and had no ancestors in common for the last three to four generations. The circumstances needed for such studies are ideally met on the island of Sardinia. The recurrent finding of the same type of association in separate breeding units between the phenotype of interest and a given genotype should allow a distinction between true genetic identity by descent and randomly occurring identities, as these will be obviously different in separate breeding units. The availability of several breeding units located in sharply different ecological environments will permit assessment of the role of nature/nurture factors in the degree of manifestation of each newly discovered genotype/phenotype association. A pilot study to evaluate the proposed strategy has been carried out in the Sardinian village of Carloforte, a community of about 8,000 individuals who have remained genetically homogeneous. Fifty-five control samples have been genotyped with six tetranucleotide microsatellites and with a subset of the 400 markers contained in the ABI PRISM linkage mapping panel, version 2. The allele frequencies for these microsatellite markers have been determined for these 55 individuals and compared to those from a random sampling of subsets of these 55 persons. For the six tetranucleotide microsatellites, a subset of as few as 20 people displayed the same allele frequency distributions as observed with the original 55 unrelated individuals. In conclusion, when samples are chosen from the same breeding unit, the number of individuals sufficient to draw the genomic profile of an isolated population can be relatively small. Likewise, the number of probands with the phenotype of interest can be even smaller when they are ascertained with the same genealogical criteria as the normal controls. By comparing the genomic profile of the probands to a fraction of the control samples within each of several separate breeding units of common remote ancestry, the search for genotype/phenotype association for mono- and multifactorial traits and diseases should be simplified and yield unequivocal results.  相似文献   

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Leishmaniasis is endemic in Sardinia but only cutaneous and visceral cases have been reported to date. We report a case of mucocutaneous leishmaniasis as presentation of HIV infection in a Sardinian patient who had never visited endemic areas. Serological and clinical diagnosis was cytologically and histopathologically confirmed. The patient had a good response to treatment with liposomal amphotericin combined with highly active antiretroviral therapy without recurrences after four years. Our case report highlights the need to better assess the circulation of species, risk factors and clinical spectrum of Leishmania infection in the Italian Mediterranean islands.  相似文献   

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Abstract

The author reports the results of the herborizations carried out on the island Piana (northeastern Sardinia) located between Cape Ceraso and Cape Coda Cavallo. The flora consists of 250 entities distributed in 154 genera, inclusive of 54 families. The author gives information regarding the mail features of the vegetal coverage, and points out the presence of two species: Limonistrum monopetalum (L.) Boiss. and Omithoga-lum arabicum L., which are extremely rare in the little islands.  相似文献   

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This paper presents archaeobotanical results from Sardinia, an island in the western Mediterranean. The starting point is the material excavated at Duos Nuraghes near Borore, but remains provided by other sites are taken into account as well. Naked wheat, presumably a tetraploid wheat such as Triticum durum Desf. (macaroni wheat), and Hordeum vulgare L. (barley) are the most common finds from the Neolithic up to the Medieval period. Triticum dicoccum Schübl. (emmer), Lens culinaris Medik. (lentil), Pisum sativum L. (pea) and Vicia faba L. var. minor (horse bean) have been grown as well. A medieval context revealed Beta vulgaris L. (beet). The most common find in the category of fruits is Vitis vinifera L. (grape). The overall picture is one of continuity in agricultural practices. Nevertheless this picture may be false. In the early Bronze Age the cultivation of barley may have shifted from the naked variety towards the hulled variety. The Phoenicians may have introduced new cultivars of grapevine, although the native grapevine was not replaced by these. The weed taxa suggest some change in agriculture from Punic or Roman times onwards. Received August 10, 2001 / Accepted January 15, 2002  相似文献   

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C. M. Calò  G. Vona 《Human Evolution》2005,20(2-3):99-106
San Pietro island is located in the Western Mediterranean basin, 4 km off the southwestern coast of Sardinia. It was first populated in 1738 by a founder group coming from the island of Tabarka (Tunisia). Many researchers focused their attention on the population of San Pietro, because of its peculiar linguistic, genetic and demographic features. In this paper we analyzed data on surnames, matrimonial structure and genetic polymorphisms. All the data demonstrated a strong differentiation of San Pietro population when it is compared with other Sardinian or Italian populations. This differentiation is due to the isolation that for century characterized the island. Moreover, medical researches discovered a high incidence of a rare genetic pathology: the high myopia. This mutant gene was probably present in the founder group and then the isolation and the high rate of endogamy and consanguinity, highlighted by matrimonial structure analysis, could have determined its diffusion. Finally, our results suggested that San Pietro genetic diversity is strictly associated with linguistic and cultural diversity.  相似文献   

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An interesting aspect of the island of Sardinia (Italy) is the wide range of genetic variability within the island itself. The variability is widened by the presence of some populations of different ethnic origin who speak a language other than Sardinian. This work deals with the study of the genetic structure of the Carloforte population which inhabits the tiny island of S. Pietro 4 km off the southwest coast of Sardinia. S. Pietro was first populated in 1738 by emigrants coming from the island of Tabarka (Tunisia) who spoke an archaic form of the Ligurian dialect. Data on genetic polymorphisms in the Carloforte population are presented and discussed in relation to some Sardinian and Italian populations. Data on demographic and matrimonial structure are also presented. The genetic analyses show the Carloforte population as being clearly separated from both Sardinians and continental Italians. The isolation of Carloforte, highlighted by language diversity, endogamy, and consanguinity levels and marriage area, supports the idea of genetic diversity linked to cultural peculiarity. © 1996 Wiley-Liss, Inc.  相似文献   

15.
Different genetic markers were used to analyze 22 Mycobacterium bovis strains isolated from cattle in Sardinia and one human isolate. IS6110 DNA fingerprinting differentiated the strains into six patterns, whereas with enterobacterial repetitive consensus sequence primers produced seven clusters. PCR ribotyping followed by digestion with HaeIII and PvuII produced five and seven patterns, respectively. PCR with the (GTG)5 oligonucleotide primer showed the best discriminatory power, generating eight clusters among the strains analyzed.  相似文献   

16.
Different genetic markers were used to analyze 22 Mycobacterium bovis strains isolated from cattle in Sardinia and one human isolate. IS6110 DNA fingerprinting differentiated the strains into six patterns, whereas with enterobacterial repetitive consensus sequence primers produced seven clusters. PCR ribotyping followed by digestion with HaeIII and PvuII produced five and seven patterns, respectively. PCR with the (GTG)5 oligonucleotide primer showed the best discriminatory power, generating eight clusters among the strains analyzed.  相似文献   

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During the winter 2003--2004 a serious disease was observed in protected tomato crops in Castrovillari, Reggio Calabria province, Southern Italy. Symptoms consisted in marginal leaf yellowing, leaf curling, plant stunting, flower abortion. The disease was detected in a group of greenhouses (about 10ha) where several tomato cultivars were grown hydroponically. The highest incidence of infection (60-100%) was observed in tomatoes grafted on Beaufort DRS tomato rootstock. Since the symptoms were similar to those described for Tomato yellow leaf curl Sardinia virus (TYLCSV) and Tomato yellow leaf curl virus (TYLCV), detection assays for these viruses were used. In DAS-ELISA positive results were obtained with a abroad-spectrums reagent combination (distributed by Bioreba AG) detecting TYLCV, TYLCSV, and other begomoviruses. When DNA probes were used in tissue print assays, positive reactions were obtained for TYLCSV, but not for TYLCV. The two probes consisted of digoxigenin-labelled DNAs representing the coat protein gene of either TYLCSV or TYLCV. Attempts to isolate the viral agent by mechanical inoculation failed, except in few cases where Potato virus Y and Tobacco mosaic virus were identified following transmission from symptomatic plants to herbaceous indicatorpplants. By contrast, grafting onto tomato seedlings always successfully transmitted the disease. In the Castrovillari area TYLCSV was not reported before. The rootstocks that nurseries used for grafting were obtained from Sicily, where the disease is endemic and both TYLCSV and TYLCV are widespread. Probably the grafted plantlets represented the primary source of infection from which subsequent diffusion by way of the vector Bemisia tabaci followed. In fact the vector had previously been detected in both the glasshouse-grown and open field tomato crops in Calabria region. TYLCV was previously reported in a different area of Calabria in 1991, but apparently it was an occasional outbreak, and B. tabaci was not detected. Since in the Castrovillari area surveyed in the present study tomato is grown throughtout the year in protected crops, the whitefly vector of the virus is present, and some natural hosts of the virus are found, it is feared that TYLCSV may become endemic, as already happened in Sicily, Sardinia, and Spain several years ago. In Spain and Sicily TYLCV, together with TYLCSV, was reported as the causal agent of very severe tomato crop losses. Therefore the danger exists that also TYLCV will reach this area, furthermore complicating the management of tomato crops.  相似文献   

19.
Background: Helicobacter pylori infection is typically acquired in childhood, and following the acute event, it is thought that most infections remain asymptomatic. H. pylori has been suggested to protect against diarrhea in childhood. Aim: To examine the role of H. pylori in gastrointestinal symptoms in children. Materials and Methods: A cross‐sectional sero‐epidemiologic study was conducted in Porto Torres, Sardinia, Italy. Demographic information, socioeconomic factors, and the frequency of upper gastrointestinal symptoms during the previous 3 months (e.g., abdominal pain, diarrhea, nausea, heartburn, halitosis, slow digestion, belching, and weight loss) were evaluated by a questionnaire. H. pylori status was determined by ELISA. Results: Approximately 95% (N = 1741) of school children between the age of 6 and 15 years from Porto Torres participated. The sero‐prevalence of H. pylori infection was 13.3% (229/1727) and similar in boys (13%) and girls (14%) (p = .57). Nausea/vomiting (odds ratio (OR) = 2.2 (95% CI = 1.2–5.1)) and diarrhea (OR = 2.1 (95% CI = 1.3–2.8)) were each significantly associated with H. pylori infection, and these associations remained significant after controlling for other study variables. There was no significant association between H. pylori and abdominal pain or heartburn (p > .25). Conclusions: The study does not support either a role of H. pylori infection in abdominal pain in children or a protective role against diarrheal illnesses or nausea/vomiting.  相似文献   

20.
There are few natural animal model systems to study autoimmune disease caused by infectious agents; however, Trypanosoma cruzi infection of the mouse offers an excellent model for the induction of autoimmunity and its consequences. In this article Klaus Petty and Harvey Eisen explain that it is probably during the acute phase of the infection that the stage is set for the long-term pathology.  相似文献   

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