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1.
Otubains are a recently identified family of deubiquitinating enzymes (DUBs). They are involved in diverse biological processes including protein degradation, signal transduction, and cell immune response. Several microsporidian genomes have been published in the last decade; however, little is known about the otubain-like protease in these widely-spread obligate intracellular parasites. Here, we characterized a 25 kDa otubain-like protease (NbOTU1) from the microsporidian Nosema bombycis, the pathogen causing pebrine disease in the economically important insect Bombyx mori. Sequence analysis showed that this protein contained a conserved catalytic triad of otubains composed of aspartate, cysteine, and histidine residues. The expression of Nbotu1 began on day 3 postinfection as determined by the RT-PCR method. Immunofluorescence analysis indicated that NbOTU1 is localized on the spore wall of N. bombycis. The subcellular localization of the NbOTU1 was further detected with immunoelectron microscopy, which showed that NbOTU1 is localized at the regions around endospore wall and plasma membrane. Deubiquitination analysis confirmed that the recombinant NbOTU1 possessed deubiquitination activity in vitro. Taken together, a novel microsporidian otubain-like protease NbOTU1 was partially characterized in N. bombycis, demonstrating its subcellular location and deubiquitination activity. This study provided a basic reference for further dissecting the function of otubains in microsporidia.  相似文献   

2.
Carbapenem-resistant Enterobacteriaceae represents a major public health issue. This study investigated the clonality and resistance mechanisms of 92 carbapenem-resistant E. coli (n?=?21) and K. pneumoniae (n?=?71) isolates collected consecutively from clinical specimens and patients at high risk of carriage between 2010 and 2012 in a healthcare region in Hong Kong. Combined disk tests (CDTs) and the Carba NP test were used for phenotypic detection of carbapenemases. PCR assays were used to detect carbapenemase genes. All isolates were intermediate or resistant to at least one carbapenem. Nine (9.8 %) isolates were genotypic carbapenemase producers and included six K. pneumoniae (one ST1306/bla IMP-4, one ST889/bla IMP-4, two ST11/bla KPC-2, one ST258/bla KPC-2, one ST483/bla NDM-1) and three E. coli (one ST131/bla IMP-4, two ST744/ bla NDM-1) isolates. All nine isolates carrying carbapenemase genes could be detected by the CDTs and the Carba NP test. PCR identified bla CTX-M and bla AmpC alone or in combination in 77.8 % (7/9) and 96.4 % (80/83) of the carbapenemase-producers and non-producers, respectively. Porin loss was detected in 22.2 % (2/9) and 59.0 % (49/83) of the carbapenemase-producers and non-producers, respectively. Overall, the E. coli clones were diverse (14 different STs), but 36.6 % (26/71) of the K. pneumoniae isolates belonged to ST11. In conclusion, the prevalence of carbapenemases among carbapenem-nonsusceptible E. coli and K. pneumoniae remained low in Hong Kong. Porin loss combined with AmpC and/or CTX-M type ESBL was the major mechanism of carbapenem resistance in the study population.  相似文献   

3.
To develop T m -shift genotyping method for detection of cat-derived Giardia lamblia, two sets of primers with two GC-rich tails of unequal length attached to their 5′-end were designed according to two SNPs (BG434 and BG170) of β-giardin (bg) gene, and specific PCR products were identified by inspection of a melting curve on real-time PCR thermocycler. A series of experiments on the stability, sensitivity, and accuracy of T m -shift method was tested, and clinical samples were also detected. The results showed that two sets of primers based on SNP could distinguish accurately between assemblages A and F. Coefficient of variation of T m values of assemblage A and F was 0.14 and 0.07% in BG434 and 0.10 and 0.11% in BG170, respectively. The lowest detection concentration was 4.52 × 10?5 and 4.88 × 10?5 ng/μL samples of assemblage A and F standard plasmids. The T m -shift genotyping results of ten DNA samples from the cat-derived G. lamblia were consistent with their known genotypes. The detection rate of clinical samples by T m -shift was higher than that by microscopy, and their genotyping results were in complete accordance with sequencing results. It is concluded that the T m -shift genotyping method is rapid, specific, and sensitive and may provide a new technological mean for molecular detection and epidemiological investigation of the cat-derived G. lamblia.  相似文献   

4.
Rapid nucleic acid amplification tests for methicillin-resistant Staphylococcus aureus (MRSA) diagnostics commonly target the mec resistance gene, genes specific for S. aureus, and the integration site for the SCCmec resistance cassette, orfX. Due to poor specificity when these target genes are used individually, additional culture is required to verify positive results. The combination of these targets is useful, but the optimal algorithm may depend on the presence of the genetic markers in S. aureus isolates, as well as the prevalence of MRSA in a population. The aim of the present study was to identify a rapid, low-cost, and functional screening algorithm in order to reduce the response time for MRSA diagnostics. An in-house orfX-SCCmec polymerase chain reaction (PCR) assay was established and evaluated. The results were compared with an existing mec/nuc PCR assay and traditional culture. Methicillin-sensitive S. aureus (MSSA) that tested false-positive in the orfX-SCCmec PCR assay were further investigated with full genome sequencing using the Ion PGM? System to verify results and causality. Based on these data, a two-step screening algorithm with initial mec/nuc PCR followed by orfX-SCCmec PCR on positive samples was suggested and tested on 1443 patient samples. 22.5 % of MSSA isolates tested false-positive with the orfX-SCCmec PCR. Full genome sequencing of these isolates identified genetic variation in the attB region of S. aureus, including empty cassette variants and non-mec SCC. The suggested two-step MRSA screening algorithm allowed us to report MRSA results for 95.6 % of all samples and 99 % of MRSA-negative samples after one day.  相似文献   

5.
In 2011, a novel mecA gene homologue, mecC, was reported in isolates from both humans and dairy cattle. The epidemiology of mecC methicillin-resistant Staphylococcus aureus (MRSA) in humans is not yet well known. In this retrospective study, we present the epidemiology of human clinical cases with mecC MRSA detected in the southern part of Sweden during the period 2005–2014. A total of 45 patients with an isolate positive for mecC MRSA were included in the study. Twenty-six isolates were found before 2012 and were retrospectively tested for mecC. Nineteen isolates were detected in 2012–2014 through routine testing. Culture results, resistance patterns, Panton–Valentine leukocidin (PVL) genes, and spa types were collected from the Clinical Microbiology Laboratory. Epidemiological data were received from the database at the Regional Centre for Communicable Disease Control and the patient’s medical files. The majority of the patients with mecC MRSA were of Swedish origin, had underlying diseases, and lived in rural areas. The median age was 60 years. Of the mecC MRSA, 76 % belonged to spa types t373 and t843. The median minimum inhibitory concentration (MIC) value for oxacillin was 16 mg/L (1–64 mg/L) and only one isolate was resistant to other classes of antibiotics. The most common type of infection was skin and soft tissue infections, most often in an existing skin lesion. The patients with mecC MRSA were colonized for a short time and gave rise to few secondary cases. mecC MRSA in our region appears to have a domestic origin and mainly affects patients with underlying diseases or patients with an existing skin lesion. Our data indicate that it could be a poor colonizer.  相似文献   

6.
DNA methylation of leukocyte DNA has been proposed to be a biomarker for cancer that can be used to target patients for appropriate clinical implementation. We investigated IGF2 DMR and LINE1 methylation in the leukocyte DNA and their association with clinicopathological features and prognosis of gastric cancer (GC) patients. Methylation status of IGF2 DMR and LINE1 in the leukocyte DNA was quantified using bisulfite pyrosequencing in 207 GC patients. Methylation of both IGF2 DMR and the LINE1 was significantly higher in the undifferentiated histologic type compared to the differentiated histologic type (both P = 0.0002). Hypermethylation of both the IGF2 DMR and the LINE1 was associated with more aggressive features of GC such as advanced stage (IGF2 DMR, P = 0.0002; LINE1, P < 0.0001), lymphatic invasion positive (IGF2 DMR, P = 0.004; LINE1, P = 0.002), venous invasion positive (IGF2 DMR, LINE1, both P = 0.03), lymph node metastasis positive (IGF2 DMR, P = 0.01; LINE1, P = 0.001), peritoneal dissemination positive (IGF2 DMR, P = 0.04; LINE1, P = 0.002), liver metastasis positive (IGF2 DMR, P = 0.008; LINE1, P = 0.001), and other distant metastasis positive (IGF2 DMR, P = 0.04). Our data suggest that high LINE1 and IGF2 DMR methylation status would be a phenomenon that is observed with the progression of GC, supporting their potential utility as a biomarker in GC patients.  相似文献   

7.
Pepo aphid-borne yellows virus (PABYV) has been proposed as a putative representative of a new species in the genus Polerovirus in the family Luteoviridae. The genomes of two South African (SA) isolates of cucurbit-infecting PABYV were described in this record. Total RNA, extracted from a pattypan (Cucurbita pepo L.) and a baby marrow (C. pepo L.) leaf samples, was subjected to next-generation sequencing (NGS) on the HiSeq Illumina platform. Sanger sequencing was subsequently used to authenticate the integrity of PABYV’s genome generated from de novo assembly of the NGS data. PABYV genome of SA isolates consists of 5813 nucleotides and displays an organisation typical of poleroviruses. Genome sequence comparisons of the SA PABYV isolates to other poleroviruses support the classification of PABYV as a new species in the genus Polerovirus. Recombination analyses showed that PABYV and Cucurbit aphid-borne yellows virus (CABYV) shared the same ancestor for the genome part situated between breaking points. Phylogenetic analyses of the RNA-dependent RNA polymerase and the coat protein genes showed that SA PABYV isolates shared distant relationship with CABYV and Suakwa aphid-borne yellows virus. Based on our results, we propose that PABYV is a distinct species in the genus Polerovirus.  相似文献   

8.
The objective of this study was to investigate the antimicrobial resistance, Tn1546 transposon variability and plasmid diversity among Polish vancomycin-resistant Enterococcus faecium (VREfm) isolates of VanA phenotype in the context of their clonal structure. Two hundred sixteen clinical VREfm isolates collected between 1997 and 2010 were studied by antimicrobial susceptibility testing, MLST, MLVA and detection of IS16, esp Efm, pilA, intA and plasmid-specific genes by PCR. Tn1546 structure was revealed by overlapping PCR and sequencing. Selected isolates were subjected to PFGE-S1 and Southern hybridization analyses. The vast majority of the isolates (95.8 %) belonged to lineages 17/18 (during the whole study period 1997–2010) and 78 (mostly in 2006–2010) of hospital-adapted meroclone of E. faecium. All isolates displayed a multi-drug resistance phenotype. Twenty-eight Tn1546 types (including 26 novel ones) were associated with eight different ISs (IS1216, IS1251, ISEfa4, ISEfa5, ISEfm2, ISEf1, IS3-like, ISEfm1-like). The vanA-determinant was typically located on plasmids, which most commonly carried rep2pRE25, rep17pRUM, rep18pEF418, rep1pIP501, ω-ε-ζ and axe-txe genes. VanA isolates from 1997–2005 to 2006–2010 differed in clonal composition, prevalence of gentamicin- and tetracycline-resistance and plasmidome. Our analysis revealed high complexity of Tn1546-type transposons and vanA-plasmids, and suggested that diverse genetic events, such as conjugation transfer, recombination, chromosomal integration and DNA mutations shaped the structure of these elements among Polish VREfm.  相似文献   

9.
The protein products of NLRP3 and CASP1 genes are involved in the cleavage of pro-IL-1B and pro-IL-18 leading to the active cytokines, which play an important role in the development of the acute coronary syndrome (ACS). The aim of the present study was to evaluate whether NLRP3 and CASP1 gene polymorphisms are biomarkers of ACS susceptibility in Mexican population. Two polymorphisms of the CASP1 gene [G+7/in6A (rs501192) and A10370-G Exon-6 (rs580253)] and one of the NLRP3 gene [UTR′3 G37562-C (rs10754558)] were genotyped by 5′ exonuclease TaqMan assays in a group of 617 patients with ACS and 609 control individuals. Under recessive model, the CASP1 G+7/in6A polymorphism was associated with an increased risk of developing ACS when compared to healthy controls (OR = 1.76, 95% CI 1.08–2.86, P Res  = 0.022). In the same way, under recessive model, the CASP1 A10370-G was associated with increased risk of ACS (OR = 1.75, 95% CI 1.07–2.85, P Res  = 0.025). Moreover, under co-dominant, dominant, over-dominant, and additive models, the NLRP3 UTR′3 G37562-C was associated with a decreased risk of ACS (OR = 0.45, 95%CI 0.22–0.92, P Co-dom  = 0.006; OR = 0.61, 95%CI 0.44–0.84, P Dom  = 0.002; OR = 0.67, 95%CI 0.48–0.94, P Over-dom  = 0.02; and OR = 0.65, 95%CI 0.50–0.94, P Add  = 0.02, respectively). In summary, this study demonstrates that the G+7/in6A and A10370-G polymorphisms of the CASP1 gene are associated with increased risk of developing ACS, whereas the UTR′3 G37562-C polymorphism of the NLRP3 gene is associated with a decreased risk of developing ACS in Mexican population.  相似文献   

10.
Further knowledge about the clinical and microbiological characteristics of prosthetic joint infections (PJIs) caused by different coagulase-negative staphylococci (CoNS) may facilitate interpretation of microbiological findings and improve treatment algorithms. Staphylococcus capitis is a CoNS with documented potential for both human disease and nosocomial spread. As data on orthopaedic infections are scarce, our aim was to describe the clinical and microbiological characteristics of PJIs caused by S. capitis. This retrospective cohort study included three centres and 21 patients with significant growth of S. capitis during revision surgery for PJI between 2005 and 2014. Clinical data were extracted and further microbiological characterisation of the S. capitis isolates was performed. Multidrug-resistant (≥3 antibiotic groups) S. capitis was detected in 28.6 % of isolates, methicillin resistance in 38.1 % and fluoroquinolone resistance in 14.3 %; no isolates were rifampin-resistant. Heterogeneous glycopeptide-intermediate resistance was detected in 38.1 %. Biofilm-forming ability was common. All episodes were either early post-interventional or chronic, and there were no haematogenous infections. Ten patients experienced monomicrobial infections. Among patients available for evaluation, 86 % of chronic infections and 70 % of early post-interventional infections achieved clinical cure; 90 % of monomicrobial infections remained infection-free. Genetic fingerprinting with repetitive sequence-based polymerase chain reaction (rep-PCR; DiversiLab®) displayed clustering of isolates, suggesting that nosocomial spread might be present. Staphylococcus capitis has the potential to cause PJIs, with infection most likely being contracted during surgery or in the early postoperative period. As S. capitis might be an emerging nosocomial pathogen, surveillance of the prevalence of PJIs caused by S. capitis could be recommended.  相似文献   

11.
Oxidative stress and abnormal DNA methylation have been implicated in some types of cancer, namely in myelodysplastic syndromes (MDS). Since both mechanisms are observed in MDS patients, we analyzed the correlation of intracellular levels of peroxides, superoxide anion, and glutathione (GSH), as well as ratios of peroxides/GSH and superoxide/GSH, with the methylation status of P15 and P16 gene promoters in bone marrow leukocytes from MDS patients. Compared to controls, these patients had lower GSH content, higher peroxide levels, peroxides/GSH and superoxide/GSH ratios, as well as higher methylation frequency of P15 and P16 gene promoters. Moreover, patients with methylated P15 gene had higher oxidative stress levels than patients without methylation (peroxides: 460 ± 42 MIF vs 229 ± 25 MIF, p = 0.001; superoxide: 383 ± 48 MIF vs 243 ± 17 MIF, p = 0.022; peroxides/GSH: 2.50 ± 0.08 vs 1.04 ± 0.34, p < 0.001; superoxide/GSH: 1.76 ± 0.21 vs 1.31 ± 0.10, p = 0.007). Patients with methylated P16 and at least one methylated gene had higher peroxide levels as well as peroxides/GSH ratio than patients without methylation. Interestingly, oxidative stress levels allow the discrimination of patients without methylation from ones with methylated P15, methylated P16, or at least one methylated (P15 or P16) promoter. Taken together, these findings support the hypothesis that oxidative stress is correlated with P15 and P16 hypermethylation.  相似文献   

12.
Chronic pulmonary aspergillosis (CPA) is associated with mortality in patients with Mycobacterium avium complex lung disease (MAC-LD). An Aspergillus-positive respiratory specimen often reflects colonization, and thus the clinical significance of Aspergillus isolation in MAC-LD patients is not well understood. The objective of this study was to investigate the clinical characteristics and outcomes of MAC-LD patients in whom Aspergillus was isolated from respiratory specimens. We performed a retrospective review of the medical records of 329 MAC-LD patients. We compared the characteristics and mortality rates between patients with Aspergillus isolation and those without. All Aspergillus species detected from respiratory specimens within the follow-up period were reviewed. Aspergillus was detected in 40 (12.2%) of the 329 patients. There were no significant differences in the clinical characteristics and mortality rates between patients with and without Aspergillus isolation. Among the 40 patients with Aspergillus isolation, 9 (22.5%) developed CPA. CPA was most often caused by A. fumigatus. In the 40 Aspergillus-positive patients, patients with A. fumigatus isolation had a significantly higher mortality rate than those without (P < 0.001). The multivariate Cox proportional hazards model showed older age (P = 0.050), presence of respiratory comorbidities (P = 0.008), hypoalbuminemia (P < 0.001), and isolation of A. fumigatus (P = 0.005) to be prognostic factors for mortality in MAC-LD patients. There was no significant difference in the mortality rates between patients with Aspergillus isolation and those without. However, isolation of A. fumigatus may be associated with poor prognosis in MAC-LD patients.  相似文献   

13.
We aimed to investigate the expressions of p27 kinase inhibitory protein 1 (p27Kip1) and calcium sensing receptor (CaSR) in adenomas and normal parathyroid tissue and to evaluate the relationship of these molecules with clinical and biochemical parameters in primary hyperparathyroidism (PHPT). Fifty-one patients with histopathologically confirmed parathyroid adenomas and 20 patients with normal parathyroid glands (which were removed incidentally during thyroid resection) were included. Immunohistochemical stainings of CaSR and p27Kip1 were performed in surgical specimens. Clinical features, biochemical parameters, and BMD measurements of patients with PHPT were evaluated retrospectively. Expressions of p27Kip1 and CaSR were decreased in parathyroid adenomas, compared to normal glands (p <?0.05). High intensity of CaSR staining (3+) was more frequent in normal parathyroid tissue (75%) than adenomas (12%) (p <?0.01). Hypertension was not observed in patients with high staining intensity of CaSR (p =?0.032). There was a negative association between CaSR expression and body mass index (BMI) (p =?0.027, r =???0.313). There was no significant relationship between p27Kip1 and CaSR expressions, serum calcium, plasma parathormone, 25-hydroxy vitamin D levels, and bone density (p >?0.05). The expressions of p27Kip1 and CaSR were decreased in PHPT patients. This reduction may play an important role in the pathogenesis of PHPT. However, neither p27Kip1 nor CaSR expression was found to be useful in predicting prognosis or severity of disease.  相似文献   

14.
Many factors may enhance or suppress the molluscicidal activity regardless of their origin. The present study aims to determine the molluscicidal activity of two plants, namely Asparagus densiflorus and Oreopanax guatemalensis besides, Difenoconazole fungicide against Biomphalaria alexandrina snails, miracidia and cercariae. The most effective agent was Difenoconazole followed by A. densiflorus and O. guatemalensis against B. alexandrina snails, where the LC90 values after 24 h of exposure reached 2.5, 102, and 188 ppm, respectively. Toxicity of tested agents was more pronounced at high temperatures. A. densiflorus and Difenoconazole showed no changes in their activities after their exposure to sunlight for 6 h. Also, neutral and acidic media were favorable for maintaining their toxic action. The presence of aquatic plants, mud particles, and storage period had negative effects on the activities of the tested agents. Both A. densiflorus and Difenoconazole had a fast effect against miracidia and cercariae of Schistosoma mansoni after 3 h of the exposure. Moreover, the tested agents recorded adverse impact on the total reproductive rate of exposed snails. Such effects were supported by histopathological examinations of the hermaphrodite gland. It showed an abnormal necrosis in male and female gametogenic cells, besides a decrease in the number of ova and other gametogenic stages.  相似文献   

15.
Staphylococcus argenteus is a novel Staphylococcus species closely related to Staphylococcus aureus that has been recently described. In this study, we investigated the proportion and the characteristics of S. argenteus recovered from humans in Belgium. S. aureus. human isolates collected in Belgium from 2006 to 2015 (n?=?1,903) were retrospectively characterised via the presence of non-pigmented colonies on chocolate agar, spa typing and rpoB sequencing to determine if some of them were in fact S. argenteus. Out of 73 strains non-pigmented on chocolate plates, 3 isolates (0.16 %) showed rpoB sequences, in addition to spa and sequence types (ST2250/t5787, ST2250/t6675, ST3240/t6675), related to S. argenteus. Two of them were methicillin-resistant, harbouring a SCCmec type IV. The three S. argenteus isolates carried genes (sak, scn) of the immune evasion cluster. This first Belgian nationwide analysis showed a low occurrence of S. argenteus. Further studies should be conducted to identify the distribution range and the clinical impact of this new species.  相似文献   

16.
Helicobacter pylori-specific genotypes have been strongly associated with an increased risk of gastric cancer (GC). The aim of the present work was to study the associations of H. pylori virulence factors, vacA i region polymorphisms and babA2 status with GC risk in Azerbaijan patients. The DNA extracted from gastric biopsy specimens was used to access the babA2 and vacA genotypes. Overall, babA2 was present in 85.39 % (76/89) of H. pylori strains: 19 out of 24 (79.16 %) strains from GC, 16 out of 17 (94.14 %) strains from peptic ulcer disease (PUD) and 41 out of 48 (85.14 %) strains from chronic gastritis. No significant association was found between babA2 genotype and clinical outcomes (P > 0.05). i1 vacA polymorphism was detected in 46/89 (51.68 %) strains: in 21/24 (87.5 %), 6/17 (35.29 %) and 19/48 (39.58 %) patients with GC, PUD and chronic gastritis, respectively. i2 allele was detected in 43 (48.31 %) out of all 89 strains examined: 3 (14.28 %) of 24 strains from GC, 11 (64.71 %) of 17 from PUD, and 29 (60.42 %) of 48 strains from chronic gastritis. In this study, multiple linear regression analysis confirmed the strong association of i1 allele with GC (partial regression correlation 0.455 ± 0.101; P = 0). Results of multiple logistic regression analysis showed that vacA i1 genotype was significantly associated with GC compared with a control group (gastritis) (odds ratio 13.142, 95 % CI 3.116–55.430; P = 0). Findings from the measurement of H. pylori babA2 and vacA genotypes indicate a strong correlation between the vacA i1 allele and GC risk in the Azerbaijan area of Iran.  相似文献   

17.
A lack of sensitive tests and difficulties obtaining representative samples contribute to the challenge in identifying etiology in pneumonia. Upper respiratory tract swabs can be easily collected and analyzed with real-time PCR (rtPCR). Common pathogens such as S. pneumoniae and H. influenzae can both colonize and infect the respiratory tract, complicating the interpretation of positive results. Oropharyngeal swabs were collected (n?=?239) prospectively from adults admitted to hospital with pneumonia. Analysis with rtPCR targeting S. pneumoniae and H. influenzae was performed and results compared with sputum cultures, blood cultures, and urine antigen testing for S. pneumoniae. Different Ct cutoff values were applied to positive tests to discern colonization from infection. Comparing rtPCR with conventional testing for S. pneumoniae in patients with all tests available (n?=?57) resulted in: sensitivity 87 %, specificity 79 %, PPV 59 % and NPV 94 %, and for H. influenzae (n?=?67): sensitivity 75 %, specificity 80 %, PPV 45 % and NPV 94 %. When patients with prior antimicrobial exposure were excluded sensitivity improved: 92 % for S. pneumoniae and 80 % for H. influenzae. Receiver operating characteristic curve analysis demonstrated for S. pneumoniae: AUC?=?0.65 (95 % CI 0.51–0.80) and for H. influenzae: AUC?=?0.86 (95 % CI 0.72–1.00). Analysis of oropharyngeal swabs using rtPCR proved both reasonably sensitive and specific for diagnosing pneumonia caused by S. pneumoniae and H. influenzae. This method may be a useful diagnostic adjunct to other methods and of special value in patients unable to provide representative lower airway samples.  相似文献   

18.
The cag (cytotoxin-associated gene) pathogenicity island (cagPAI) is one of the major virulence determinants of Helicobacter pylori (H. pylori). The purpose of this study was to investigate the association of the three genes (tnpA, tnpB, and cagA) in H. pylori isolated from Azerbaijani patients with the different gastrointestinal disease. A total of 362 gastric biopsies were collected from hospitals of Tabriz University of Medical Sciences, and were cultured on Brucella agar. The tnpA, tnpB, and cagA genes were detected by PCR. Of the total 264 H. pylori isolates, tnpA, tnpB, and cagA genes were detected in 120 (45.5%), 56 (21.2%) and 172 (65.2%), respectively. A significant association between tnpA and tnpB genes and clinical outcomes were found (P < 0.05). The cagA status was not related to clinical outcomes in our subjects. The predominant genotype among cag-PAI is the cagA. The prevalence of tnpA, tnpB, and cagA genes are high in patients with gastric cancer, and a significant association is revealed between tnpA and tnpB with gastric cancer.  相似文献   

19.
Pediatric papillary thyroid carcinoma (PTC) has unique features but requires further genetic investigation. Moreover, there has been increasing concern about the risk for pediatric PTC in Japan after the Fukushima accident. This study aims to evaluate the frequencies of BRAF and TERT promoter mutations and to examine their significance in non-radiation-associated pediatric PTCs in Japan. We enrolled 81 pediatric PTC patients aged ≤20 years. The control group included 91 adult PTCs from patients >20 years old. BRAF and TERT mutations were analyzed by allele-specific-PCR and/or Sanger sequencing. Compared with adult PTCs, pediatric PTCs exhibited larger tumor size, more frequent lymph node metastasis, and less classical histology. The prevalence of BRAF V600E in pediatric PTCs was 54% and significantly lower than that in adults of 85%. In the pediatric PTCs, BRAF V600E was positively associated with older age, classical histology, and the lymph node metastasis but independent from other clinicopathological factors. TERT mutations were identified in 13% of adults and in none of the pediatric PTCs. In conclusion, pediatric PTCs are characterized by more advanced clinicopathological features, lower BRAF V600E frequency, and absence of TERT mutation. The BRAF V600E frequency in this study is similar to the reported BRAF V600E frequency in the ultrasonographically screened pediatric PTCs in Fukushima.  相似文献   

20.
Prevalence of invasive ß-haemolytic streptococci (BHS) at a tertiary care hospital and molecular diversity of S. pyogenes and S. dysgalactiae was studied. Between 2012 and 2016, all blood culture sets (n?=?55,839), CSF (n?=?8413) and soft tissue (n = 20,926) samples were analysed for BHS positivity using HYBASE software. Molecular profiles of 99 S. pyogenes and S. dysgalactiae were identified by sequencing of M protein genes (emm types) and multiplex PCR typing of 20 other virulence determinants. Streptococci contributed to 6.2% of blood, 10.7% of CSF and 14.5% of soft tissue isolates, being among the most common invasive isolates. The overall rates of invasive S. pyogenes, S. agalactiae, S. dysgalactiae and S. pneumoniae were 2.4, 4.4, 2.1, and 5.3%. Whereas S. pneumoniae was 1.5% more common in CSF samples, BHS isolates were 2-fold and 11-fold higher in bacteraemia and invasive soft tissue infections. Genetic BHS typing revealed wide molecular diversity of invasive and noninvasive group A and group G BHS, whereas one emm-type (stG62647.0) and no other virulence determinants except scpA were detected in invasive group C BHS. BHS were important invasive pathogens, outpacing S. pneumoniae in bacteraemia and invasive soft tissue infections. The incidence of S. dysgalactiae infections was comparable to that of S. pyogenes even with less diversity of molecular virulence. The results of this study emphasise the need for awareness of BHS invasiveness in humans and the need to develop BHS prevention strategies.  相似文献   

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