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1.
The population structure of two alleles similarly affected by selection, HbS and Beta-thalassemia, was studied in the same area, in Sicily. It was observed that Beta-thalassemia has uniform frequencies over the island, and that HbS shows a South-North cline. A singularity exists for HbS, in the twon of Butera, where the frequency of the S gene is six times higher than the island average. It was advanced that probably HbS entered Sicily from North Africa, when the Beta-thalassemia allele was already established in the Island. From the correlation analysis concluded that HbS came to Sicily with the frequency of HbS, it was concluded that HbS came to Sicily before the Arab invasions of the 700 's AD.  相似文献   

2.
During 1978-81 there were about 43,500 births in Birmingham, of which 10.3% were to Negroes and 22.6% to Asians. Cellulose acetate electrophoresis of red cell haemolysates from capillary specimens collected for phenylketonuria screening was performed for these babies to assess the feasibility, cost, and benefits of detecting sickle haemoglobinopathies early. Eight babies had important haemoglobinopathies; four were homozygotes for haemoglobin S (HbS), three were mixed heterozygotes for HbS and haemoglobin C (HbC), and one had haemoglobin E (HbE) and beta-thalassemia. Also, 534 (1.19%) were heterozygotes for HbS or haemoglobin D (HbD) and 205 (0.46%) for HbC or HbE, 453 (1.01%) were heterozygotes with a fast-moving band, one was a heterozygote for haemoglobin Norfolk, and one a heterozygote for both HbS and haemoglobin G Philadelphia. The cost of neonatal screening for haemoglobinopathies was 12.5 p per baby (705 pounds for each serious abnormality).  相似文献   

3.
A list of myxomycetes collected in Pantelleria, a volcanic island located 110 km southwest of the island of Sicily (Italy), is presented with data on distribution. Forty-nine taxa were identified, 38 of which are new for Sicily. The myxomycete diversity of Pantelleria was also compared with that of other volcanic islands located in the Atlantic and Pacific oceans.  相似文献   

4.
Because of their relative simplicity and the barriers to gene flow, islands are ideal systems to study the distribution of biodiversity. However, the knowledge that can be extracted from this peculiar ecosystem regarding epidemiology of economically relevant diseases has not been widely addressed. We used information available in the scientific literature for 10 old world islands or archipelagos and original data on Sicily to gain new insights into the epidemiology of the Mycobacterium tuberculosis complex (MTC). We explored three nonexclusive working hypotheses on the processes modulating bovine tuberculosis (bTB) herd prevalence in cattle and MTC strain diversity: insularity, hosts and trade. Results suggest that bTB herd prevalence was positively correlated with island size, the presence of wild hosts, and the number of imported cattle, but neither with isolation nor with cattle density. MTC strain diversity was positively related with cattle bTB prevalence, presence of wild hosts and the number of imported cattle, but not with island size, isolation, and cattle density. The three most common spoligotype patterns coincided between Sicily and mainland Italy. However in Sicily, these common patterns showed a clearer dominance than on the Italian mainland, and seven of 19 patterns (37%) found in Sicily had not been reported from continental Italy. Strain patterns were not spatially clustered in Sicily. We were able to infer several aspects of MTC epidemiology and control in islands and thus in fragmented host and pathogen populations. Our results point out the relevance of the intensity of the cattle commercial networks in the epidemiology of MTC, and suggest that eradication will prove more difficult with increasing size of the island and its environmental complexity, mainly in terms of the diversity of suitable domestic and wild MTC hosts.  相似文献   

5.
The extent of variation in the migratory movements that occurred in Sicily was evaluated using surname data taken from the telephone directories of the 390 communes of the island. The surname distribution of each commune was linearized by a log-log transformation, and a significant fit to a linear regression model was found in almost all cases. Interestingly, the slope of the regression line appeared to be a sensitive indicator of the different level of isolation associated with each Sicilian commune. By this approach, two distinct groups of communes, showing a higher or lower degree of isolation, were obtained, and two independent analyses of the surname structure of Sicily were carried out. A first multidimensional scaling analysis, based on the more isolated communes, yielded evidence for a more ancient pattern, characterized by a geographical gradient along the east-west axis. The same analysis, addressed to the less isolated communes, instead highlighted a wide network of interactions between geographically distant zones of the island. The fitting of the surname distribution to the log-log model allowed for the detection of a narrow subset of 35 Sicilian communes, whose significantly higher degree of isolation was statistically proved by the parallelism test. We believe that a genetic analysis focused on such specific zones of the island could reveal ancient patterns of differentiation, thus helping to answer the controversial question of the genetic history of Sicily.  相似文献   

6.
This report describes the occurrence, study and molecular diagnostics of 40 Hb O Arab beta 121 Glu Lys cases and 4 Hb D punjab beta 121 Glu Gln cases in Bulgaria. Hematological, morphological and clinical data for 12 patients with Hb O arab are listed. Among them we observed 7 simple heterozygotes for Hb O Arab/Hb A, two double heterozygotes-compounds for Hb O/beta+-thalassemia and three compounds for Hb O/beta 0-thalassemia (the latter assumed). Also, general hematological, morphological and clinical data are presented for 4 Hb D Punjab carriers, from which two are simple heterozygotes and two are assumed, as compounds for Hb D/beta 0-thalassemia. The consideration of heterozygosity, homozygosity for both abnormal hemoglobins and of the compound state of Hb O or Hb D/beta-thalassemia or HbS types let us suggest the relative neutrality of the variants and the limitation in their distribution, depending on genetic structure of populations, where they spread. It may be concluded that human hemoglobin is characterized by marked monomorphism. At the same time, the high frequency of HbS, HbE and HbC in some populations can be well explained by contemporary selectionism; the distribution of relatively neutral Hb D Punjab and Hb O Arab with some limitations can follow Kimura's neutralism concept.  相似文献   

7.
Aims: The aim of this study was to identify the non‐Saccharomyces yeast populations present in the grape must microflora from wineries from different areas around the island of Sicily. Methods and Results: Yeasts identification was conducted on 2575 colonies isolated from six musts, characterized using Wallerstein Laboratory (WL) nutrient agar, restriction analysis of the amplified 5·8S‐internal transcribed spacer region and restriction profiles of amplified 26S rDNA. In those colonies, we identified 11 different yeast species originating from wine musts from two different geographical areas of the island of Sicily. Conclusions: We isolated non‐Saccharomyces yeasts and described the microflora in grape musts from different areas of Sicily. Moreover, we discovered two new colony morphologies for yeasts on WL agar never previously described. Significance and Impact of the Study: This investigation is a first step in understanding the distribution of non‐Saccharomyces yeasts in grape musts from Sicily. The contribution is important as a tool for monitoring the microflora in grape musts and for establishing a new non‐Saccharomyces yeast collection; in the future, this collection will be used for understanding the significance of these yeasts in oenology.  相似文献   

8.
Abstract

The aim of this article was to test the way in which geographical factors influence island floras in the Mediterranean basin, using ferns as target organisms, and the islands surrounding Sicily as location. A matrix with presence/absence data concerning fern taxa in the 16 islands studied was compiled. Cluster analysis, principal co-ordinates analysis (PCoA), principal components analysis (PCA) and a Bayesian analysis were performed. For each island, the total number of fern taxa was regressed against three factors: island area, island elevation and isolation. All the analyses pointed to affinities between islands according to their different geological composition, independently from their geographic position. A clear positive island species/area relationship (ISAR) was shown only for the volcanic islands. The island species/(area×elevation) relationship (ISAER), on the contrary, was unsatisfactory. The main features of interest are the following: (1) the clear division of the islands into two groups, volcanic vs. sedimentary; (2) the floristic richness of the volcanic compared to sedimentary islands and (3) the uniqueness of the pteridophyte flora of Pantelleria. This seems to demonstrate that the lower number of taxa in the islands farthest away from the “mainland” (Sicily, Tunisia) is not due to isolation, but due to another factor, probably habitat availability.  相似文献   

9.
Hemoglobinopathies are the most commonly inherited genetic disorders in India. Certain communities in India have a high predisposition to beta-thalassemia. To offer prenatal diagnosis and to prevent the birth of an affected child, mutation testing in clinically diagnosed beta-thalassemia patients/carriers is a prerequisite. Over a period of 4 years, we have conducted DNA analysis in 385 carriers for 15 beta-thalassemia mutations, HbD, HbE, and HbS. Using reverse dot blot (RDB) and amplification refractory mutation system (ARMS), we have been able to identify mutations in 381 of 385 thalassemia chromosomes. The study included the analysis of five common mutations found in Asian Indians, namely IVS1-5 (G-C), 619-bp deletion, IVS1-1 (G-T), and the frameshifts at CD8/9(+G) and CD41/42(-CTTT). The occurrence of these five mutations was seen in 299 (91.2%) carriers referred to us, the percentage of mutations varying between 4.0 and 68.9%. We also found Cd16 (-C) in 2.1%, CD30 (G-C) in 1.5%, and CD 15(G-A) in 0.6%; these are considered common mutations in the Indian population, as well. The beta-thalassemia anomaly in 4 (0.6%) carriers remained uncharacterized by RDB and ARMS analysis. During delineation of the mutations in uncharacterized carriers by single-stranded conformational polymorphism (SSCP) and sequencing analysis, we have also been able to identify two unusual mutations, one involving an initiation codon and the second involving a novel 8-bp deletion, in Indian families of Uttar Pradesh origin.  相似文献   

10.
To improve the differentiation of thalassemia intermedia from other hemoglobinopathies in Iran, four known genetic mechanisms-XmnI (G)gamma polymorphism, inheritance of mild and silent beta-thalassemia alleles, delta beta deletion, and coinheritance of alpha- and beta-thalassemia-were investigated in 52 Iranian individuals suspected to have thalassemia intermedia based on clinical and hematological characteristics. Beta-globin mutations were studied using a reverse-hybridization assay and sequencing of the total beta-globin gene. The XmnI (G)gamma polymorphism, the Sicilian delta beta deletion, and four alpha-globin mutations (-a(3.7), -a(4.2), -(MED), aaa(anti-3.7)) were studied using PCR-based techniques. The inheritance of the XmnI (G)gamma polymorphism with severe beta-thalassemia alleles in the homozygous or compound heterozygous state was the predominant mechanism observed in 27 individuals (55.3%). In five cases, this status overlapped with the -a(3.7)/aa genotype. The second most frequent cause for thalassemia intermedia (14.8%) was the inheritance of mild beta-thalassemia alleles, including IVS-I-6 (T > C), -88 (C > A), and + 113 (A > G). In three subjects (4.3%) the Sicilian delta beta deletion was identified. HbS in association with beta-zero-thalassemia was found in three patients with thalassemia intermedia phenotype. In 11 cases (21.3%) no causative genetic alteration could be identified. Our results reflect the diversity underlying thalassemia intermedia, and the limitations of the applied clinical, hematological, and molecular approaches for correct diagnosis. Some of the unresolved cases will offer an opportunity to discover additional molecular mechanisms leading to thalassemia intermedia.  相似文献   

11.
Aim To investigate the importance of various island characteristics in determining spatial patterns of variations in beta diversity for various animal groups. Location Analyses are presented for 10 animal groups living on the Aeolian Islands, a volcanic archipelago in the central Mediterranean, near Sicily. Methods Three hypotheses were formulated to explain patterns of beta diversity: the target‐area–distance effect, stepping stone dispersal and island age. Matrices of inter‐island dissimilarities were constructed under each hypothesis and correlated with matrices of faunal dissimilarities using Mantel tests. For the ‘target‐area–distance effect’ hypothesis, inter‐island dissimilarities were calculated using island sizes and distances to nearest mainland areas. For the ‘stepping stone dispersal’ hypothesis, inter‐island distances were measured. Finally, for the ‘island age’ hypothesis, inter‐island dissimilarities were calculated on the basis of the geological age of the islands. Cluster analysis was used to investigate inter‐island faunal relationships. Results Support for a target‐area–distance effect was found only for birds. For these highly mobile animals, inter‐island distances had no significant effects on beta diversity. Birds are known to colonize islands by crossing large sea barriers and thus they can easily reach the Aeolian Islands, which are close to source areas (notably Sicily). Inter‐island distances had a significant role in determining patterns of beta diversity in most invertebrates. For Mollusca, Opiliones, Chilopoda, Heteroptera, coprophagous Scarabaeoidea, and Tenebrionidae, even relatively short distances preclude invertebrates from colonizing an island regularly from the mainland, and most colonization probably results from inter‐island faunal exchanges. Island age was proved to be important only for orthopterans. Main conclusions The origin of most of the Aeolian invertebrate fauna is quite recent, and species appear to have established on the islands predominantly by stepping stone dispersal. Birds, which are highly mobile organisms, follow more direct mainland–island dynamics. As further studies on other islands become available, comparative analyses will confirm whether the factors influencing variations in beta diversity in this study and their relationships with species dispersal ability are consistent across scales and geographical context.  相似文献   

12.
Citrus tristeza virus (CTV) outbreaks were detected in Sicily island, Italy for the first time in 2002. To gain insight into the evolutionary forces driving the emergence and phylogeography of these CTV populations, we determined and analyzed the nucleotide sequences of the p20 gene from 108 CTV isolates collected from 2002 to 2009. Bayesian phylogenetic analysis revealed that mild and severe CTV isolates belonging to five different clades (lineages) were introduced in Sicily in 2002. Phylogeographic analysis showed that four lineages co-circulated in the main citrus growing area located in Eastern Sicily. However, only one lineage (composed of mild isolates) spread to distant areas of Sicily and was detected after 2007. No correlation was found between genetic variation and citrus host, indicating that citrus cultivars did not exert differential selective pressures on the virus. The genetic variation of CTV was not structured according to geographical location or sampling time, likely due to the multiple introduction events and a complex migration pattern with intense co- and re-circulation of different lineages in the same area. The phylogenetic structure, statistical tests of neutrality and comparison of synonymous and nonsynonymous substitution rates suggest that weak negative selection and genetic drift following a rapid expansion may be the main causes of the CTV variability observed today in Sicily. Nonetheless, three adjacent amino acids at the p20 N-terminal region were found to be under positive selection, likely resulting from adaptation events.  相似文献   

13.
The genetic structure of the population of Alia (Sicily, Italy) was analyzed using 15 short tandem repeats: TPOX, D2S1338, D3S1358, FIBRA, D5S818, CSF1PO, D7S820, D8S1179, TH01, VWA, D13S317, D16S539, D18S51, D19S433, and D21S11. Two of these markers, D2S1338 and D19S433, have never before been used in research on population genetics and only recently have they been put to use in forensic medicine. Results of the analysis underline the genetic isolation of the Alia population and show it to be a recent bottleneck as a consequence of a cholera epidemic in 1837. While comparing the Alia population with other populations from Sicily, a genetic heterogeneity within Sicily was uncovered, thus confirming previous results obtained from the analysis of classical markers. This heterogeneity underlines the existence of genetic boundaries within the island. Comparisons with other Italian, Mediterranean, and European populations highlight the differentiation of the Sicilian population, reflecting the presence of a genetic boundary that separates Sicily from northern and central Italy and from the western Mediterranean basin.  相似文献   

14.
Genetic structure of the population of Sicily.   总被引:1,自引:0,他引:1  
Genetic heterogeneity within Sicily was investigated on the basis of ACP1, ADA, ESD, GLO1, PGD, PGM1, PGM2, SODA, ABO, and MN gene frequencies, and compared to those of other regions of Italy for which these same loci have been examined. Correspondence analysis revealed no differences within the island, at least at the provincial level, but showed genetic differentiation among Italian regions, distinctly clustering northern, central, and southern populations, respectively. These data indicate a close relationship between Sicily and southern Italy. In addition, the contribution of Middle Eastern populations to the gene pool of Sicily was evident.  相似文献   

15.
Red cells from patients with sickle cell disease contain HbS rather than the normal HbA (here termed HbS cells). On deoxygenation, HbS cells exhibit a distinctive solute permeability pathway, P(sickle), activated stochastically, and partially inhibited by DIDS and dipyridamole. It is often referred to as a cation channel although its permeability characteristics remain vague and its molecular identity is unknown. We show that, in contrast to normal red cells, a proportion of HbS cells underwent haemolysis when deoxygenated in isosmotic non-electrolyte solutions. Haemolysis was stochastic: cells unlysed after an initial deoxygenation pulse showed lysis when harvested, reoxygenated and subsequently exposed to a second period of deoxygenation. O(2) dependence of haemolysis was similar to that of P(sickle) activation. Haemolysis was accompanied by high rates of sucrose influx, and both haemolysis and sucrose influx were inhibited by DIDS and dipyridamole. Sucrose influx was only detected as ionic strength was reduced below 80 mM. These findings are consistent with the postulate that deoxygenation of HbS cells, under certain conditions, activates a novel non-electrolyte pathway. Their significance lies in understanding the nature of the deoxygenation-induced permeability in HbS cells, together with its relationship with novel pathways induced by a variety of manipulations in normal red cells.  相似文献   

16.
S T Saad  F F Costa 《Human heredity》1992,42(2):125-128
The frequency of glucose-6-phosphate dehydrogenase (G-6-PD) deficiency was determined in 54 male patients with sickle cell diseases: 31 sickle cell anemia (SS), 14 sickle cell hemoglobinopathy (SC) and 9 HbS/beta-thalassemia (S/B-thal) by a combination of quantitative assay, fluorescent spot test and electrophoresis. Of the 54 patients tested, 7 were found to be G-6-PD deficient (G-6-PD-) (3 SS, 3 SC and 1 S/B-thal) and 47 G-6-PD normal (G-6-PD+) (6 G-6-PD A and 41 G-6-PD B). All the deficient patients were G-6-PD A-. The frequency of G-6-PD deficiency did not differ significantly from that observed in the general population. Compared to patients who were not G-6-PD-, there were no significant differences in the hemoglobin concentration and reticulocyte count in patients with sickle cell diseases who were G-6-PD-.  相似文献   

17.
Mass screening in the Geok-chai region of Azerbaijan covered 264 persons. 2 families with abnormal hemoglbin were detected. Electrophoresis in PAG and on cellulose acetate films as well as sickling test showed that in 3 out of 9 members of one of the families HbS was detected. 6 out of 8 members of the others family appeared to be HbD-carriers. In 4 members of this family abnormal hemoglobin was found out in combination with G-6-PDH deficiency. No clinical manifestations were found. A number of beta-thalassemia cases were detected in screened children as well as in adults. Hemoglobin oxygen equilibrium curves were studied in patients with heterozygous beta-thalassemia. In case of G-6-PDH deficiency when it is not possible to obtain active enzyme zones on the columns with PAG these zones can be detected when CoCl2 (2 mM) is added into the incubation medium.  相似文献   

18.
In some continental and island sites in the western Mediterranean basin, the Holocene vegetation and climate dynamics seem to show the same patterns in time and space. Nevertheless, different synchronous scenarios have been proposed from other south European, North African and Near Eastern pollen records from around the Mediterranean basin. Striking similarities and synchronisms have been found between Sicily and the Balearic Islands. These islands, although under different bioclimatic influences, show similarities in the main trends of vegetation and climate dynamics during the Post-glacial. Lago di Pergusa is the only natural inland lake in Sicily and because of its geographical location, has a good potential sensitivity to the climatic changes of the Mediterranean basin. Likewise, coastal sediments from Minorca and Majorca, the Balearic Islands, have similar peculiarities. The present-day environmental situation, now that most of the natural vegetation in these islands has disappeared, has been brought about either by a climatic trend towards increasing aridity or an increase in human activities. It seems clear that prehistoric human people alone could not have caused all the environmental changes recorded in the last millennia in both places.  相似文献   

19.
In this paper a conservation biogeography approach has been applied to predict distribution and conservation priorities in West Mediterranean Zygaena moths. The presence/absence matrix data for mainland region and for the three largest islands (Sardinia, Corsica and Sicily) has been analyzed. The analyses have been performed on individual species and revealed that species distribution in the Mediterranean mainland can be largely predicted. However, Sardinia and Corsica islands showed highly impoverished faunas while Sicily did not revealed a lower richness than predicted. Logistic regressions at individual species level showed that several taxa, predicted to be present in Sardinia and Corsica are actually absent. For Sicily the opposite trend was obtained and several unpredicted species actually occur on this island. Conversely to butterflies, ecological traits did not differ between predicted and unpredicted Sicilian species, suggesting that ancient and stochastic colonisations are responsible for the occurrence of several species. Due to the very low probabilities that relict populations could re-colonize islands following possible extinctions, they are suggested to deserve particular conservation efforts. In particular, Z. orana from Sardinia, Z. corsica from Corsica and Z. trifolii, Z. purpuralis and Z. carniolica from Sicily showed distinctive biogeographic patterns and/or particular rarity.  相似文献   

20.
Vegetation History and Archaeobotany - The present study concerns the Phoenician-Punic site of Motya, a small island set in Western Sicily (Italy), in the Marsala Lagoon (Stagnone di Marsala),...  相似文献   

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