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1.
泌尿生殖道沙眼衣原体omp1基因多态性研究   总被引:1,自引:1,他引:0  
从中国不同城市收集疑为沙眼衣原体(Ct)感染的泌尿生殖道标本323份,巢式PCR扩增Ctomp1基因片段(包括4个变异区),测定其中96份阳性标本omp1基因序列,根据同源性分型并分析其多态位点;根据氨基酸序列,用Mega 3软件构建进化树,分析临床株与相应参考株之间的亲缘关系。从96份沙眼衣原体阳性标本中,检出28种基因变体,其中E型最常见;同时发现Ct E、F型omp1基因高度保守,而其它基因型都显示一定的变异性。进化树分析发现,各临床株与相应参考株之间遗传距离较近。实验结果表明沙眼衣原体omp1基因呈现较大的多态性,可为其疫苗的研制及感染的防治提供重要的实验依据。  相似文献   

2.
The purpose of this study was to determine prevalence of Chlamydia trachomatis (Ct) urogenital infection and its serotype distribution from clinical samples in north-eastern Croatia. During a 3-year period, 2,379 urogenital samples were analyzed by real-time polymerase chain reaction (A group), while 4,846 genital swabs were analyzed by direct fluorescent antibody test (B group). 132 Ct positive specimens were genotyped by omp1 gene sequencing. The prevalence rate of Ct was 3.2 % in A and 1 % in B group. The most prevalent chlamydial genotype was E (44 %), followed by F (33 %), K (11.5 %), G (8 %), J/UW (5.3 %), D-IC (4.4 %), D-B120 (1.8 %), and B/IU, J/IU, Ia/IU (0.9 % each) serotypes. Single-nucleotide polymorphisms (SNPs) of omp1 gene were detected in E, K, and G serotypes. Some of these SNPs (C/T at position 272 and G/A at position 813 in E strain; C/T at position 884 in D strain) might represent novel omp1 variants.  相似文献   

3.

Background

Hepatitis B virus (HBV) genotypes have a distinct geographical distribution and influence disease progression and treatment outcomes. The purpose of this study was to investigate the distribution of HBV genotypes in Europe, the impact of mutation of different genotypes on HBV gene abnormalities, the features of CpG islands in each genotype and their potential role in epigenetic regulation.

Results

Of 383 HBV isolates from European patients, HBV genotypes A-G were identified, with the most frequent being genotype D (51.96%) in 12 countries, followed by A (39.16%) in 7 countries, and then E (3.66%), G (2.87%), B (1.57%), F (0.52%) and C (0.26%). A higher rate of mutant isolates were identified in those with genotype D (46.7%) followed by G (45.5%), and mutations were associated with structural and functional abnormalities of HBV genes. Conventional CpG island I was observed in genotypes A, B, C, D and E. Conventional islands II and III were detected in all A-G genotypes. A novel CpG island IV was found in genotypes A, D and E, and island V was only observed in genotype F. The A-G genotypes lacked the novel CpG island VI. “Split” CpG island I in genotypes D and E and “split” island II in genotypes A, D, E, F and G were observed. Two mutant isolates from genotype D and one from E were found to lack both CpG islands I and III.

Conclusions

HBV genotypes A-G were identified in European patients. Structural and functional abnormalities of HBV genes were caused by mutations leading to the association of genotypes D and G with increased severity of liver disease. The distribution, length and genetic traits of CpG islands were different between genotypes and their biological and clinical significances warrant further study, which will help us better understand the potential role of CpG islands in epigenetic regulation of the HBV genome.  相似文献   

4.
This study describes a new multilocus variable number tandem-repeat (VNTR) analysis (MLVA) typing system for the discrimination of Chlamydia trachomatis genovar D to K isolates or specimens. We focused our MLVA scheme on genovar E which predominates in most populations worldwide. This system does not require culture and therefore can be performed directly on DNA extracted from positive clinical specimens. Our method was based on GeneScan analysis of five VNTR loci labelled with fluorescent dyes by multiplex PCR and capillary electrophoresis. This MLVA, called MLVA-5, was applied to a collection of 220 genovar E and 94 non-E genovar C. trachomatis isolates and specimens obtained from 251 patients and resulted in 38 MLVA-5 types. The genetic stability of the MLVA-5 scheme was assessed for results obtained both in vitro by serial passage culturing and in vivo using concomitant and sequential isolates and specimens. All anorectal genovar E isolates from men who have sex with men exhibited the same MLVA-5 type, suggesting clonal spread. In the same way, we confirmed the clonal origin of the Swedish new variant of C. trachomatis. The MLVA-5 assay was compared to three other molecular typing methods, ompA gene sequencing, multilocus sequence typing (MLST) and a previous MLVA method called MLVA-3, on 43 genovar E isolates. The discriminatory index was 0.913 for MLVA-5, 0.860 for MLST and 0.622 for MLVA-3. Among all of these genotyping methods, MLVA-5 displayed the highest discriminatory power and does not require a time-consuming sequencing step. The results indicate that MLVA-5 enables high-resolution molecular epidemiological characterisation of C. trachomatis genovars D to K infections directly from specimens.  相似文献   

5.
Sequences of the major outer membrane protein (MOMP) gene (ompA) and the outer membrane complex B protein gene (omcB) from Chlamydia trachomatis, Chlamydia pneumoniae, and Chlamydia psittaci were analyzed for evidence of intragenic recombination and for linkage equilibrium. The Sawyer runs test, compatibility matrices, and index of association analyses provided substantial evidence that there has been a history of intragenic recombination at ompA including one instance of interspecies recombination between the C. trachomatis mouse pneumonitis strain and the C. pneumoniae horse N16 strain. Although none of these methods detected intragenic recombination within omcB, differences in divergence reported in earlier studies suggested that there has been intergenic recombination involving omcB, and the analyses presented in this study are consistent with this. For C. trachomatis, index-of-association analyses suggested a higher degree of recombination for C class than for B class strains and a higher degree of recombination in the downstream half of ompA. In concordance with these findings, many significant breakpoints were found in variable segments 3 and 4 of MOMP for the recombinant strains D/B120, G/UW-57, E/Bour, and LGV-98 identified in this study. We provide examples of how genetic diversity generated by repeated recombination in these regions may be associated with evasion of immune surveillance, serovar-specific differences in tissue tropism, and persistence.  相似文献   

6.
The complete amino acid sequence of coagulogen purified from the hemocytes of the horseshoe crab Carcinoscorpius rotundicauda was determined by characterization of the NH2-terminal sequence and the peptides generated after digestion of the protein with lysyl endopeptidase, Staphylococcal aureus protease V8 and trypsin. Upon sequencing the peptides by the automated Edman method, the following sequence was obtained: A D T N A P L C L C D E P G I L G R N Q L V T P E V K E K I E K A V E A V A E E S G V S G R G F S L F S H H P V F R E C G K Y E C R T V R P E H T R C Y N F P P F V H F T S E C P V S T R D C E P V F G Y T V A G E F R V I V Q A P R A G F R Q C V W Q H K C R Y G S N N C G F S G R C T Q Q R S V V R L V T Y N L E K D G F L C E S F R T C C G C P C R N Y Carcinoscorpius coagulogen consists of a single polypeptide chain with a total of 175 amino acid residues and a calculated molecular weight of 19,675. The secondary structure calculated by the method of Chou and Fasman reveals the presence of an alpha-helix region in the peptide C segment (residue Nos. 19 to 46), which is released during the proteolytic conversion of coagulogen to coagulin gel. The beta-sheet structure and the 16 half-cystines found in the molecule appear to yield a compact protein stable to acid and heat. The amino acid sequences of coagulogen of four species of limulus have been compared and the interspecies evolutionary differences are discussed.  相似文献   

7.
DNA sequences coding for 81% of the ompA gene from 24 chlamydial strains, representing all chlamydial species, were determined from DNA amplified by polymerase chain reactions. Chlamydial strains of serovars and strains with similar chromosomal restriction fragment length polymorphism had identical ompA DNA sequences. The ompA sequences were segregated into 23 different ompA alleles and aligned with each other, and phylogenetic relationships among them were inferred by neighbor-joining and maximum parsimony analyses. The neighbor-joining method produced a single phylogram which was rooted at the branch between two major clusters. One cluster included all Chlamydia trachomatis ompA alleles (trachoma group). The second cluster was composed of three major groups of ompA alleles: psittacosis group (alleles MN, 6BC, A22/M, B577, LW508, FEPN, and GPIC), pneumonia group (Chlamydia pneumoniae AR388 with the allele KOALA), and polyarthritis group (ruminant and porcine chlamydial alleles LW613, 66P130, L71, and 1710S with propensity for polyarthritis). These groups were distinguished through specific DNA sequence signatures. Maximum parsimony analysis yielded two equally most parsimonious phylograms with topologies similar to the ompA tree of neighbor joining. Two phylograms constructed from chlamydial genomic DNA distances had topologies identical to that of the ompA phylogram with respect to branching of the chlamydial species. Human serovars of C. trachomatis with essentially identical genomes represented a single taxonomic unit, while they were divergent in the ompA tree. Consistent with the ompA phylogeny, the porcine isolate S45, previously considered to be Chlamydia psittaci, was identified as C. trachomatis through biochemical characteristics. These data demonstrate that chlamydial ompA allelic relationships, except for human serovars of C. trachomatis, are cognate with chromosomal phylogenies.  相似文献   

8.
The spectrum of mutations in the low-density lipoprotein (LDL) receptor gene was studied in a sample of hypercholesterolemia patients of Caucasoid origin from the population of Russia. The examined patients were 45 to 49 years old and had the highest level of total serum cholesterol in this age group. Seven previously nondescribed mutations have been revealed in exon 9 (R410G; M412V) and in exon 12 (Y/Y576; N/N591; L605V; L605R; A612G). Twelve previously described mutations have been identified in exons 2 (C/C27), 5 (C261F; E240X), 6 (E288K), 8 (A391T), 9 (E418G; L432R; D433E), 11 (G/G549; E558K; L/L568), and 12 (G592E). Only one of these mutations was previously described in Russia in a clinical sample of patients with familial hypercholesterolemia. The spectrum of LDL receptor gene mutations in the population sample of patients with hypercholesterolemia significantly differs from the mutation spectrum in patients with familial hypercholesterolemia (clinical samples). Sequencing of the LDL receptor gene is a highly efficient method for identifying the markers of hypercholesterolemia predisposition in a population.  相似文献   

9.
The polymerase chain reaction (PCR) method has been employed to amplify a chlamydial genome encoding four variable segments of the major outer membrane protein and genotyping of different Chlamydia trachomatis serovars was successfully achieved by means of restriction fragment length polymorphism (RFLP) analysis and sequencing of amplified DNA. These methods were applied to identify the serotypes of C. trachomatis in endocervical specimens obtained from asymptomatic pregnant Japanese women at 28-30 weeks of gestation. Among the 218 specimens, 207 were serotyped 43 (19.3%) as serovar D, 53 (24.3%) as E, 24 (11.0%) as F, 39 (17.9%) as G, 15 (6. 9%) as H, 15 (6.9%) as I, five (2.3%) as J, nine (4.1%) as K and four (1.8%) as mixed. Among the 11 unclassified strains by RFLP, six (2.8%) were identified as serovar B variants and five (2.3%) were identified as D/IC-Cal-8. It was suggested that variants of endemic trachoma serovars also have affinity for the urogenital tract of Japanese pregnant women.  相似文献   

10.
Chlamydia trachomatis is a major cause of ocular and sexually transmitted diseases worldwide. While much of our knowledge about its genetic diversity comes from serotyping or ompA genotyping, no quantitative assessment of genetic diversity within serotypes has been performed. To accomplish this, 507 urogenital samples from a multicenter U.S. study were analyzed by phylogenetic and statistical modeling. No B, Da, or I serotypes were represented. Based on our analyses, all but one previous urogenital B serotype was identified as Ba. This, coupled with the lack of B serotypes in our population, suggests that B has specific tropism for ocular mucosa. We identified a Ba/D recombinant (putative crossover nucleotide 477; P < 0.0001) similar to a B/D mosaic we described previously from an African trachoma patient. Computational analyses of the Ba/D recombinant indicated that upstream changes were less important for tissue tropism than downstream incorporation of the D sequence. Since most serotypes had nonsynonymous/synonymous ratios of <1.0, the major outer membrane protein, encoded by ompA, has many functional constraints and is under purifying selection. Surprisingly, all serotype groups except for J had a unimodal population structure indicating rapid clonal expansion. Of the groups with a unimodal structure, E and Ia and, to a lesser extent, G and K were prevalent, had infrequent incorporation of mutations, and, compared to other groups, had a relatively greater degree of diversifying selection, consistent with a selective sweep of mutations within these groups. Collectively, these data suggest a diverse evolutionary strategy for different serogroups of the organism.  相似文献   

11.
This paper presents the complete amino acid sequence of the low molecular weight acid phosphatase from bovine liver. This isoenzyme of the acid phosphatase family is located in the cytosol, is not inhibited by L-(+)-tartrate and fluoride ions, but is inhibited by sulfhydryl reagents. The enzyme consists of 157 amino acid residues, has an acetylated NH2 terminus, and has arginine as the COOH-terminal residue. All 8 half-cystine residues are in the free thiol form. The molecular weight calculated from the sequence is 17,953. The sequence was determined by characterizing the peptides purified by reverse-phase high performance liquid chromatography from tryptic, thermolytic, peptic, Staphylococcus aureus protease, and chymotryptic digests of the carboxymethylated protein. No sequence homologies were found with the two known acylphosphatase isoenzymes or the metalloproteins porcine uteroferrin and purple acid phosphatase from bovine spleen (both of which have acid phosphatase activity). Two half-cystines at or near the active site were identified through the reaction of the enzyme with [14C] iodoacetate in the presence or in the absence of a competitive inhibitor (i.e. inorganic phosphate). Ac-A E Q V T K S V L F V C L G N I C R S P I A E A V F R K L V T D Q N I S D N W V I D S G A V S D W N V G R S P N P R A V S C L R N H G I N T A H K A R Q V T K E D F V T F D Y I L C M D E S N L R D L N R K S N Q V K N C R A K I E L L G S Y D P Q K Q L I I E D P Y Y G N D A D F E T V Y Q Q C V R C C R A F L E K V R-OH.  相似文献   

12.
The association of infectious burden of Chlamydia trachomatis with patient characteristics and clinical disease may have implications for understanding disease pathogenesis. We examined chlamydial load from 171 urine samples where load was based on copy number of organisms per copy number of eukaryotic cells derived by real-time quantitative PCR. High- (E, F, G) and low-prevalence (Ia, H, J, Ja) genotypes in the population had similar loads, suggesting a similar propensity for replicating in vivo, despite their differential ecological success. Symptomatic and asymptomatic patients also had similar chlamydial loads, indicating that virulence differences are likely not associated with variations in replication. There was a significant difference in genotypes by age for F (<31 years; P = 0.031) and for H where the mean age was lower than for the most prevalent genotype, E (P=0.013). Also, men had a significantly lower load than women when the genotype was F (P=0.042), although there was no significant difference in load between partners. Patients with recurrent chlamydial infections had a significant reduction in load with each subsequent episode regardless of genotype (P=0.007), suggesting that immune defenses do not block chlamydial entry but may impact replication. Additionally, the probability of being infected with J was 7.7-fold higher in patients with prior chlamydial infections (P=0.016), and although the loads were lower when compared with patients without prior infection, the results did not reach statistical significance. These findings suggest that chlamydial burden could be an important marker for recurrence and host immune response, which would facilitate pathogenesis research.  相似文献   

13.
BACKGROUND: Fabry disease (OMIM 301500) is an X-linked inborn error of glycosphingolipid metabolism resulting from mutations in the alpha-galactosidase A (alpha-Gal A) gene. The disease is phenotypically heterogeneous with classic and variant phenotypes. To assess the molecular heterogeneity, define genotype/phenotype correlations, and for precise carrier identification, the nature of the molecular lesions in the alpha-Gal A gene was determined in 40 unrelated families with Fabry disease. MATERIALS AND METHODS: Genomic DNA was isolated from affected males or obligate carrier females and the entire alpha-Gal A coding region and flanking sequences were amplified by PCR and analyzed by automated sequencing. Haplotype analyses were performed with polymorphisms within and flanking the alpha-Gal A gene. RESULTS: Twenty new mutations were identified (G43R, R49G, M72I, G138E, W236X, L243F, W245X, S247C, D266E, W287C, S297C, N355K, E358G, P409S, g1237del15, g10274insG, g10679insG, g10702delA, g11018insA, g11185-delT), each in a single family. In the remaining 20 Fabry families, 18 previously reported mutations were detected (R49P, D92N, C94Y, R112C [two families], F113S, W162X, G183D, R220X, R227X, R227Q, Q250X, R301X, R301Q, G328R, R342Q, E358K, P409A, g10208delAA [two families]). Haplotype analyses indicated that the families with the R112C or g10208delAA mutations were not related. The proband with the D266E lesion had a severe classic phenotype, having developed renal failure at 15 years. In contrast, the patient with the S247C mutation had a variant phenotype, lacking the classic manifestations and having mild renal involvement at 64 years. CONCLUSIONS: These results further define the heterogeneity of alpha-Gal A mutations causing Fabry disease, permit precise heterozygote detection and prenatal diagnosis in these families, and provide additional genotype/phenotype correlations in this lysosomal storage disease.  相似文献   

14.
Seventeen mutations in beta-subunit of Escherichia coli F1-ATPase which had previously been characterized in strain AN1272 (Mu-induced mutant) were expressed in strain JP17 (beta-subunit gene deletion). Six showed unchanged behavior, namely: C137Y; G142D; G146S; G207D; Y297F; and Y354F. Five failed to assemble F1F0 correctly, namely: G149I; G154I; G149I,G154I; G223D; and P403S,G415D. Six assembled F1F0 correctly, but with membrane ATPase lower than in AN1272, namely: K155Q; K155E; E181Q; E192Q; D242N; and D242V. AN1272 was shown to unexpectedly produce a small amount of wild-type beta-subunit; F1-ATPase activities reported previously in AN1272 were referable to hybrid enzymes containing both mutant and wild-type beta-subunits. Purified F1 was obtained from K155Q; K155E; E181Q; E192Q; and D242N mutants in JP17. Vmax ATPase values were lower, and unisite catalysis rate and equilibrium constants were perturbed to greater extent, than in AN1272. However, general patterns of perturbation revealed by difference energy diagrams were similar to those seen previously, and the new data correlated well in linear free energy relationships for reaction steps of unisite catalysis. Correlation between multisite and unisite ATPase activity was seen in the new enzymes. Overall, the data give strong support to previously proposed mechanisms of unisite catalysis, steady-state catalysis, and energy coupling in F1-ATPases (Al-Shawi, M. K., Parsonage, D. and Senior, A. E. (1990) J. Biol. Chem. 265, 4402-4410). The K155Q, K155E, D242N, and E181Q mutations caused 5000-fold, 4000-fold, 1800-fold, and 700-fold decrease, respectively, in Vmax ATPase, implying possibly direct roles for these residues in catalysis. Experiments with the D242N mutant suggested a role for residue beta D242 in catalytic site Mg2+ binding.  相似文献   

15.
A six-year prospective study of Chlamydia trachomatis infection and ocular disease in Tanzanian village children was conducted to identify the determinants of trachoma endemicity using sequencing of ompA. Overall, 749 conjunctival samples were obtained, with 176 children sampled in both 1989 and 1995. 31.1% (233/749) were positive by PCR-enzyme immunoassay, and 76% (176/233) of the positives were sequenced in variable domains (VD) 1 to 4 (22 children in both 1989 and 1995). Twenty-six ompA genotypes of serovar A, and 19 of B/Ba were identified, and only 20% of genotypes identified in 1995 matched those found in 1989. In particular, B/Ba genotypes exhibited a 15-base region in VD 2 with increased nucleotide substitution, and these types were associated with age and water availability. Homotypic infection and infection with multiple genotypes and high chlamydial load did predict subsequent severe trachoma (odds ratio (OR) = 10.14, 95% confidence interval (CI): 1.71, 60.23; OR = 6.40, 95% CI: 0.75, 54.41; OR = 6.74, 95% CI: 0.82, 55.38, respectively). And, multitypic infection was clustered with residence of village and associated with familial cattle ownership. In conclusion, high ompA polymorphism and the inability of some hosts to clear infection with the same ompA genotype suggest two distinct but converging mechanisms of endemic severe trachoma.  相似文献   

16.
Chlamydia trachomatis is the leading cause of bacterial sexually transmitted diseases worldwide. Urogenital strains are classified into serotypes and genotypes based on the major outer membrane protein and its gene, ompA, respectively. Studies of the association of serotypes with clinical signs and symptoms have produced conflicting results while no studies have evaluated associations with ompA polymorphisms. We designed a population-based cross-sectional study of 344 men and women with urogenital chlamydial infections (excluding co-pathogen infections) presenting to clinics serving five U.S. cities from 1995 to 1997. Signs, symptoms and sequelae of chlamydial infection (mucopurulent cervicitis, vaginal or urethral discharge; dysuria; lower abdominal pain; abnormal vaginal bleeding; and pelvic inflammatory disease) were analyzed for associations with serotype and ompA polymorphisms. One hundred and fifty-three (44.5%) of 344 patients had symptoms consistent with urogenital chlamydial infection. Gender, reason for visit and city were significant independent predictors of symptom status. Men were 2.2 times more likely than women to report any symptoms (P=0.03) and 2.8 times more likely to report a urethral discharge than women were to report a vaginal discharge in adjusted analyses (P=0.007). Differences in serotype or ompA were not predictive except for an association between serotype F and pelvic inflammatory disease (P=0.046); however, the number of these cases was small. While there was no clinically prognostic value associated with serotype or ompA polymorphism for urogenital chlamydial infections except for serotype F, future studies might utilize multilocus genomic typing to identify chlamydial strains associated with clinical phenotypes.  相似文献   

17.
The primary structure of a 61-amino-acid residue peptide from the pancreas of the European eel (Anguilla anguilla) has been established as E E K S G(5)L Y R K P(10)S C G E M(15)S A M H A(20)C P M N F(25)A P V C G(30)T D G N T(35)Y P N E C(40)S L C F Q(45)R Q N T K(50)T D I L I(55)T K D D R(60)C. There was no indication of microheterogeneity. This peptide shows structural similarity to pancreatic secretory trypsin inhibitors from several mammalian species and to a cholecystokinin-releasing peptide isolated from rat pancreatic juice. A comparison of the amino acid sequences of the peptides has identified a domain in the central region of the molecules that has been strongly conserved during evolution. In contrast, the amino acid sequence in the region corresponding to the reactive centre of the mammalian trypsin inhibitors is very poorly conserved in the eel peptide. The P1-P1' reactive site lysine-isoleucine (or arginine-isoleucine) bond in the mammalian trypsin inhibitors is replaced by a methionine-asparagine bond. This region does, however, show limited homology to the reactive centre of human alpha 1-protease inhibitor suggesting that the eel peptide may function as an inhibitor of other proteolytic enzymes in the pancreas.  相似文献   

18.
This study used pyrosequencing to determine the proportional distribution of CYP3A5*3 genotypes to further confirm the homogeneous phenomenon that is observed when recipients and donors in living donor liver transplantation (LDLT) have a different single nucleotide polymorphism (SNP) genotype. We enrolled 42 recipient/living donor pairs and the SNPs of CYP3A5*3 were identified by polymerase chain reaction-restriction fragment length polymorphism. We performed 120 liver graft biopsies as part of clinical investigations after LDLT. Pyrosequencing of the CYP3A5*3 SNPs revealed that among the 16 recipients with the G/G genotype, 94.68% had the G and 5.32% the A allele. Among the 14 recipients with the A/G genotype, 78.08% had the G and 21.92% the A allele, and among the 12 recipients with the A/A genotype, 18.45% had the G and 81.55% the A allele. Among the 12 donors with the G/G genotype, 93.85% had the G and 6.14% the A allele. Among the 26 donors with the A/G genotype, 75.73% had the G and 24.27% the A allele, and among the 4 donors with the A/A genotype, 11.09% had the G and 88.91% the A allele. There were a total of 120 liver graft biopsy samples; among the 37 recipients with the G/G genotype, 89.74% had the G and 10.26% the A allele, among the 70 recipients with the A/G genotype, 71.57% had the G and 28.43% the A allele, and among the 13 recipients with the A/A genotype, 48.25% had the G and 51.75% the A allele. The proportional distribution of G and A alleles of the CYP3A5*3 SNP between recipients/donors and liver grafts after LDLT was significantly different (p<0.001). Pyrosequencing was useful in identifying detailed proportional changes of the CYP3A5*3 SNP allele distribution, and to confirm the homogeneous phenomenon when recipients and donors in LDLT have a different genotype.  相似文献   

19.
We studied the prevalence of Chlamydia trachomatis (CT) urogenital infection and the distribution of different genotypes in a non-selected STD population of 1625 patients, evaluating presence of coinfections with other sexually transmitted diseases. Each patient was bled to perform serological tests for syphilis and HIV, then urethral or endocervical swabs were obtained for the detection of CT and Neisseria gonorrhoeae by culture. DNA extracted from remnant positive swabs was amplified by omp1 Nested PCR and products were sequenced. Total prevalence of CT infection was 6.3% (103/1625), with strong differences between men and women (11.4% vs 3.9%, P<0.01). Clinical symptoms and coinfections were much more frequent in men than in women (P<0.01). The most common serovar was E (prevalence of 38.8%), followed by G (23.3%), F (13.5%) D/Da (11.6%) and J (4.8%). Serovars distribution was statistically different between men and women (P=0.042) and among patients with or without coinfection (P=0.035); patients infected by serovar D/Da showed the highest coinfection rate. This study can be considered a contribution in increasing knowledge on CT serovar distribution in Italy. Further studies are needed to better define molecular epidemiology of CT infection and to investigate its correlation with other STDs.  相似文献   

20.
This is the first study to investigate vertical transmission of Chlamydia trachomatis in Chongqing China. For this study, 300 cervical swab samples from pregnant women and 305 nasopharygeal swab samples from their babies (605 specimens) were collected for nest polymerase chain reaction (nPCR) of the ompl gene, which encodes the major outer membrane protein (MOMP) and typed C. trachomatis using Cleavase fragment-length polymorphism (CFLP) labeled with digoxin. From these samples, 11% (33/300) of pregnant women samples were successfully amplified. The vertical transmission rate of C. trachomatis from mother to baby was 24% (8/33). The vertical transmission rates were 66.7% (6/9) for mothers with vaginal delivery and 8.3% (2/24) for those with cesarean section. The incidence of premature membrane rupture among C. trachomatis-positive pregnant women was 30.3% (10/33), which was greater than among those who were C. trachomatis-negative (13.5%, 36/267; χ2 = 4.2; < 0.05). Four genotypes including type E (3 pairs), type F (2 pairs), type H (2 pairs), and type D (1 pair) were observed by CFLP assay labeled with digoxin and confirmed by DNA sequencing in the 16 C. trachomatis-positive samples from eight pregnant women and their eight infants. Each pair of matched maternal–infantile samples showed identical CFLP. This study showed the incidence of C. trachomatis infection in pregnant women, the vertical transmission rate for C. trachomatis, and the genotypes of C. trachomatis in Chongqing, China. The CFLP assay labeled at the 5′ end of the forward primer with digoxin was first used successfully to genotype of C. trachomatis. As a promising method for C. trachomatis genotyping, CFLP had good sensitivity, reproducibility, and simplicity and no radioactive contamination.  相似文献   

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