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Shobha Narahari Abida Juwle Subhankar Basak Dhananjaya Saranath 《Infection, genetics and evolution》2009,9(4):643-645
Viral hepatitis represents a major global health problem with 170 million Hepatitis C Virus (HCV) carriers worldwide, and 12–13 million HCV carriers in India. HCV genotypes are of clinical significance in indicating drug responsiveness and prognosis of the patient. The HCV genotypes are of epidemiologic significance as well, as they are indicative of transmission route of infection and have not been extensively studied in the Indian context. In the current study, HCV genotyping was examined in 2118 patients from different geographic regions of India. HCV was detected by PCR amplification of 5′ UTR and core-envelope1 regions, followed by genotyping using nucleotide sequencing and analysis with NCBI tool (http://www.ncbi.nlm.nih.gov/projects/genotyping/formpage.cgi). HCV genotype distribution in the 2118 Indian patients demonstrated prevalence of HCV3 (3a/3b primarily) in 62% and HCV1 (1a/1b primarily) in 31% patients. The predominance of HCV3 was significant in northern (p = 0.01) and eastern (p = 0.008) regions of India. HCV types 2, 4, 5, and 6 were detected in 0.05–4.5% of the patient group. Thus, our studies demonstrate HCV genotype prevalence in the cohort group in different regions of India. 相似文献
5.
BACKGROUND: Middle ear pathology, either otitis media with effusion or
tubal dysfunction, is frequently seen in day-care centre children.
Recognition and early treatment of this condition is crucial to the
prevention of chronic otitis media, which is a major cause of hearing loss
in later life. OBJECTIVES: We aimed to reveal the incidence of silent
otitis media in day-care centre children and to determine the predisposing
factors, risk factors and the awareness of the parents of the middle ear
disease of their children. METHOD: Two hundred and thirteen children, aged
3-6 years, were screened in four daycare centres. A questionnaire was
prepared that would reveal the predisposing factors. Information was
gathered from both the parents and teachers. Children were examined by
otoscopy, pneumotoscopy, tympanometry and X-rays for sinus pathology.
RESULTS: Forty-three of 213 children had middle ear pathology; 39 of them
were confirmed by tympanometry; 56.1 % of children had some degree of sinus
pathology. We revealed that, although most of the children do not have the
risk factors, they develop middle ear pathology. Among the parents, 81.4%
of them were unaware of the condition. CONCLUSION: Early diagnosis of
middle ear pathologies is necessary for prevention of future complications.
In early stages the condition is silent. We emphasize the importance of the
primary care physician's role in diagnosing the early stages of middle ear
pathologies and recommend that teaching of otoscopic and pneumotoscopic
skills should be part of the training for family physicians.
相似文献
6.
Codon usage studies have been carried out on the coding sequences of Thermoplasma acidophilum, which is an archaeon and grows at very low pH and high temperature. Overall codon usage data analysis indicates that all the four bases are almost equifrequent at the third position of codons, which is expected (since genomic GC % of this genome is about 46%). However, multivariate statistical analysis indicates that there are two major trends in the codon usage variation among the genes in this organism. In the first major trend it is observed that genes having G and C ending codons are clustered at one end while, A and T ending ones are clustered at the other end. We have also found a significant positive correlation between the expressivities of genes and GC contents at the synonymous third codon positions. In the second major trend, it is seen that the genes are clustered into three distinct parts. A comparative analyses of codon usage data of T. acidophilum and Sulfolobus solfataricus reveals that one of the three clusters of genes of T. acidophilum is very similar to a considerable number of S. solfataricus genes, suggesting possible occurrences of lateral gene transfer between these two microorganisms as reported by earlier workers. 相似文献
7.
The bias favoring deletion over inversion in DH-JH rearrangement has been
known for years, but the underlying mechanism has yet to be fully defined.
It has been suggested that the ratio of deletion/inversion is determined by
the combined effect of two factors: (i) the relative strengths of 5' and 3'
recombination signal sequences (RSS) of a DH segment, and (ii) the
efficiency with which the deletional product (one joint) forms relative to
the inversional product (two joints). In this study, we analyzed for the
first time the effect of factor 1 alone on the biased 3' RSS utilization in
DH-JH joining by using deletional plasmids in an extrachromosomal substrate
V(D)J recombination assay. It was found that the 3' RSS and associated
coding end (12 bp) mediate recombination more efficiently than the 5'
RSS/coding end DH-JH plasmids. These results demonstrate that the effect of
the RSS/coding end alone can account, at least partially, for the
predominant deletion in DH-JH recombination. The potential effect of the
relative strength of RSS and associated coding end on the ordered
rearrangement of DH-JH followed by VH to DH-JH was also assessed. When
recombination frequencies of D-->J (3' DH to J3) were compared with
frequencies of V-- >D (VHPJ14 to 3' DH or VHOX2 to 3' DH), it was found
that V-->D joining was, if anything, more efficient than D-->J
joining. Therefore, if all three segments were accessible, RSS/coding end
effects would not contribute to the ordered rearrangement of the IgH locus.
相似文献
8.
Bulent Urman Cengiz Alatas Senai Aksoy Alp Nuhoglu Aycan Sertac Basak Balaban 《Journal of assisted reproduction and genetics》1998,15(3):125-128
Purpose:
Our purpose was to determine the feasibility and efficacy of performing testicular or epididymal sperm retrieval prior to the injection of human chorionic gonadotropin (hCG).
Methods:
This report deals with 87 sperm-positive percutaneous epididymal sperm aspiration (PESA), percutaneous testicular sperm aspiration (PTSA), or testicular sperm extraction (TESE) cycles. All sperm retrieval procedures were performed prior to administration of hCG to the women. Retrieved spermatozoa were cultured in vitro in simple medium for approximately 40 hr prior to intracyto-plasmic sperm injection.
Results:
In all but one cycle in which TESE was performed for nonobstructive azoospermia, motile sperm were available for ICSI. The overall fertilization rate was 53%. Pregnancy rate per transfer and implantation rate per embryo were 41.2 and 15.7%, respectively.
Conclusions:
Satisfactory fertilization and pregnancy rates can be achieved when PESA, PTSA, or TESE is performed prior to the injection of hCG followed by in vitro culture of spermatozoa approximately 40 hr before ICSI. Scheduling of testicular or epididymal sperm retrieval cases in this way appears to ease the workload on laboratory and operating room personnel. Furthermore, withholding hCG when sperm is absent may obviate the unnecessary risk of ovarian hyperstimulation when spermatozoa cannot be retrieved. 相似文献
9.
Risk of tuberculous infection among healthcare workers in a tertiary-care hospital in Ankara, Turkey. 总被引:1,自引:0,他引:1
Ramazan Keskiner Onder Erg?nül Ziya Demiroglu Sebnem Eren Nurcan Baykam Basak Dokuzoguz 《Infection control and hospital epidemiology》2004,25(12):1067-1071
OBJECTIVE: To determine risk factors for tuberculin skin test (TST) positivity among healthcare workers (HCWs). DESIGN: Two-step TST was performed in 2002. SETTING: Tertiary-care hospital in Ankara, Turkey. PARTICIPANTS: A sample of 491 hospital HCWs were included. Information related to demographics, profession, work duration, department, and individual and family history of tuberculosis (TB) was obtained by a structured questionnaire. RESULTS: Four hundred eight (83%) had two-step TST positivity. On multivariate analysis, male physicians (relative risk [RR], 1.5; 95% confidence interval [CI95], 1.23-1.69; P = .001), nurses (RR, 1.5; CI95, 1.29-1.66; P = .005), radiology technicians (RR, 1.7; CI95, 1.35-1.73; P = .002), laboratory technicians (RR, 1.6; CI95, 1.3-1.74; P = .007), and male housekeepers (RR, 1.6; (HCWs). CI95, 1.38-1.7; P < .001) had a higher risk than did female physicians. Among laboratory technicians, radiology technicians had the highest TST positivity (85%). HCWs working for less than 1 year (RR, 0.8; CI95, 0.72-0.98; P = .027) had a lower risk of infection. The HCWs having bacille Calmette-Guerin vaccination (RR, 1.12; CI95, 1.08-1.45) had higher TST positivity. CONCLUSION: Male physicians, nurses, and laboratory technicians had increased risk of Mycobacterium tuberculosis infection in this setting, but community exposure likely accounted for most infections. 相似文献
10.
Yang PY Almofti MR Lu L Kang H Zhang J Li TJ Rui YC Sun LN Chen WS 《第二军医大学学报》2006,27(6):637-637
Polygonum multiflorum stilbeneglycoside (PMS) is a water-soluble fraction of Polygonum multiflorum Thunb. , one of the most famous tonic traditional Chinese medicines, that has protective effects on the cardiovascular system. The purpose of the present study is to elucidate the effects of PMS on macrophage-derived foam cell functions and the reduction of severity of atherosclerosis in hypercholesterolemic New Zealand White (NZW) rabbits. NZW rabbits were fed for 12 weeks with a normal diet, a high cholesterol diet, or a high cholesterol diet associated with irrigation with different doses of PMS (25, 50, or 100 mg/kg). Treatment of NZW rabbits fed with high cholesterol diet with 100 mg/kg PMS attenuated the increase in plasma cholesterol, low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol, and plasma triglyceride. Treatment with 50 and 100 mg/kg PMS caused 43% and 60% decrease in atherosclerotic lesioned area ratio to total surface area, respectively. In U937 foam cells, PMS could decrease the high expression of intercellular adhesion molecule (ICAM)-1 protein and the vascular endothelial growth factor (VEGF) protein levels in the medium induced by oxidized lipoprotein when analyzed by flow cytometry. The results proved that PMS is a powerful agent against atherosclerosis and that PMS action could possibly be through the inhibition of the expression of ICAM-1 and VEGF in foam cells. 相似文献