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Detection of Vi-negative Salmonella enterica serovar typhi in the peripheral blood of patients with typhoid fever in the Faisalabad region of Pakistan 下载免费PDF全文
Baker S Sarwar Y Aziz H Haque A Ali A Dougan G Wain J Haque A 《Journal of clinical microbiology》2005,43(9):4418-4425
The synthesis and transportation proteins of the Vi capsular polysaccharide of Salmonella enterica serovar Typhi (serovar Typhi) are encoded by the viaB operon, which resides on a 134-kb pathogenicity island known as SPI-7. In recent years, Vi-negative strains of serovar Typhi have been reported in regions where typhoid fever is endemic. However, because Vi negativity can arise during in vitro passage, the clinical significance of Vi-negative serovar Typhi is not clear. To investigate the loss of Vi expression at the genetic level, 60 stored strains of serovar Typhi from the Faisalabad region of Pakistan were analyzed by PCR for the presence of SPI-7 and two genes essential for Vi production: tviA and tviB. Nine of the sixty strains analyzed (15%) tested negative for both tviA and tviB; only two of these strains lacked SPI-7. In order to investigate whether this phenomenon occurred in vivo, blood samples from patients with the clinical symptoms of typhoid fever were also investigated. Of 48 blood samples tested, 42 tested positive by fliC PCR for serovar Typhi; 4 of these were negative for tviA and tviB. Three of these samples tested positive for SPI-7. These results demonstrate that viaB-negative, SPI-7-positive serovar Typhi is naturally occurring and can be detected by PCR in the peripheral blood of typhoid patients in this region. The method described here can be used to monitor the incidence of Vi-negative serovar Typhi in regions where the Vi vaccine is used. 相似文献
3.
Amyn A. Malik Neel R. Gandhi Timothy L. Lash Lisa M. Cranmer Saad B. Omer Junaid F. Ahmed Sara Siddiqui Farhana Amanullah Aamir J. Khan Salmaan Keshavjee Hamidah Hussain Mercedes C. Becerra 《Emerging infectious diseases》2021,27(3):805
In Karachi, Pakistan, a South Asian megacity with a high prevalence of tuberculosis (TB) and low HIV prevalence, we assessed the effectiveness of fluoroquinolone-based preventive therapy for drug-resistant (DR) TB exposure. During February 2016–March 2017, high-risk household contacts of DR TB patients began a 6-month course of preventive therapy with a fluoroquinolone-based, 2-drug regimen. We assessed effectiveness in this cohort by comparing the rate and risk for TB disease over 2 years to the rates and risks reported in the literature. Of 172 participants, TB occurred in 2 persons over 336 person-years of observation. TB disease incidence rate observed in the cohort was 6.0/1,000 person-years. The incidence rate ratio ranged from 0.29 (95% CI 0.04–1.3) to 0.50 (95% CI 0.06–2.8), with a pooled estimate of 0.35 (95% CI 0.14–0.87). Overall, fluoroquinolone-based preventive therapy for DR TB exposure reduced risk for TB disease by 65%. 相似文献
4.
Andrea C. Perez Aamir M. Khawaja Clive P. Page William Paul 《European journal of pharmacology》1997,330(2-3):241-246
Plasma protein extravasation has been measured in guinea pig skin using
-albumin and blood flow using
enon (
e) clearance. The nitric oxide (NO) synthase inhibitors NG-nitro-
-arginine methyl ester (
-NAME), NG-monomethyl-
-arginine (l
NMMA) and NG-nitro-
-arginine (
-NOArg) and the α-adrenoceptor agonist, phenylephrine, inhibited bradykinin induced plasma protein extravasation when co-injected with the peptide. The inhibitory effects of
-NAME and
-NOArg lasted for up to 8 and 4 h, respectively, whereas phenylephrine and
-NMMA had no persistent inhibitory effects. When co-injected with
e,
-NAME,
-NMMA,
-NOArg and phenylephrine, but not
-NAME, produced significant reductions in skin blood flow. When injected prior to
e,
-NAME and
-NOArg, but not phenylephrine or
-NMMA, significantly reduced flow. The effect of
-NAME on flow was not significant at 8 h. Thus, although the inhibitory effects of the NO synthase inhibitors on mediator induced plasma protein extravasation show correlations with their effects on blood flow, the persistent effect of
-NAME on exudation appears to extend beyond its effect on flow. 相似文献
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Rakan S. Al-Essa Mohammed D. Al-Otaibi Bader S. Al-Qahtani Emad M. Masuadi Aamir Omair Hind M. Alkatan 《Saudi Journal of Ophthalmology》2019,33(1):1-6
Purpose
The main purpose of the study was to examine and identify factors that influence the future practice pattern of Saudi Board of Ophthalmology residents as well as their academic goals. This study also aimed to compare the plans and career goals of the current Saudi ophthalmology residents with a former cohort of Saudi ophthalmology residents.Methods
All current residents of Saudi Board of Ophthalmology were invited to complete an anonymous online survey in March 2017. Residents were contacted by email. The survey contained questions on demographics, plans and factors influencing career choice of the residents in their future. Data were categorized by gender. Chi-square was used to assess the effect of gender on outcomes where appropriate.Results
Of 150 residents surveyed, 91 (61%) responded to the survey. Having the ability to combine medicine and surgery was the most motivating factor for pursuing an ophthalmology residency training program (81% of respondents). Most residents expressed an interest in providing refractive surgery (62%), being involved in research activities (85%) and working part-time in the private sector (73%). The majority (81%) expressed a desire to practice in an urban setting as well as pursuing fellowship training (81%). Anterior segment (31%) and surgical retina (15%) were the most popular choices for fellowship training.Conclusion
Increasing interest in joining fellowship training programs (mostly in surgical subspecialties) and being involved in research activities among current generation of ophthalmology residents have been observed compared to a previous cohort study in the same country. 相似文献7.
Aamir Cheema Chandrasekhar R. Vasamreddy Darshan Dalal Joseph E. Marine Jun Dong Charles A. Henrikson David Spragg Alan Cheng Saman Nazarian Sunil Sinha Henry Halperin Ronald Berger Hugh Calkins 《Journal of interventional cardiac electrophysiology》2006,15(3):145-155
Background Two important limitations of the data regarding the outcomes of catheter ablation of atrial fibrillation (AF) are the short-term follow-up used in most published studies and the lack of single-procedure outcomes.Objective The objective was to report the long-term single-procedure outcomes at our center.Materials and methods The patient population was comprised of 200 consecutive patients who underwent ablation (133 men; age 56 ± 11 years). Atrial fibrillation was paroxysmal in 92 (46%). Success was defined as absence of symptomatic AF, off antiarrhythmic drug (AAD) after a single procedure.Results After a follow-up of 26 ± 11 months, the single-procedure long-term success rate was 28% with an additional 7% of patients demonstrating improvement. After including repeat procedures in 64 patients, the overall long-term success rate was 41% with 11% demonstrating improvement. Further subgroup analysis of 48 paroxysmal AF patients considered to be optimal candidates for the procedure, revealed a long-term success rate of 69% with an additional 4% demonstrating improvement. A major complication occurred in 7.9% of patients.Conclusion The results reveal that the long-term single-procedure success rate of catheter ablation of AF in a cohort of patients with predominantly non-paroxysmal AF is less than 40%. The inclusion of redo procedures resulted in an improvement in outcomes. A much higher success rate of 69% was achieved in patients with paroxysmal AF considered to be optimal candidates for this procedure. These results make it clear that further advances in the technique of catheter ablation of AF are needed to improve the safety and efficacy of this procedure. In order to be able to compare outcomes of various techniques in differing patient populations, we urge investigators to report long-term single procedure outcomes.This study was supported by The Norbert and Louise Grunwald Cardiac Arrhythmia Research Fund. 相似文献
8.
A retrospective study of 25 children with gastrointestinal perforation due to blunt abdominal trauma in a single region of Pakistan is presented. The age, sex, aetiology, site of perforation, abdominal and X-ray findings, associated injuries, surgical procedures and outcome were analysed. There were 20 boys and 5 girls: mean age was 10 years. The injuries were the result of road traffic accidents 12 (48%), falls 11 (44%) and 'struck by animals' two (8%). Associated injuries occurred in 19 (76%). On admission 20 (80%) patients had peritonitis while 18 (72%) had pneumoperitoneum. Mean time from trauma to admission was 10 hours and admission to operation was 5 hours. Ileum was the most common site of perforation. Simple closure was the most common surgical procedure. Complications occurred in nine (36%) patients--six (24%) died. Delay in presentation and operation was associated with increased morbidity and mortality. Frequent evaluation of the child and abdominal X-rays are still the important tools for early diagnosis of gastrointestinal perforation following blunt abdominal trauma. 相似文献
9.
Syed Ali Arsalan Naqvi Nasreen Badruddin Munsif Ali Jatoi Aamir Saeed Malik Wan Hazabbah Baharudin Abdullah 《Australasian physical & engineering sciences in medicine / supported by the Australasian College of Physical Scientists in Medicine and the Australasian Association of Physical Sciences in Medicine》2015,38(4):721-729
10.
Aamir Javaid William W. Chu Edouard Cheneau Leonardo C. Clavijo Lowell F. Satler Kenneth M. Kent Neil J. Weissman Augusto D. Pichard Ron Waksman 《Cardiovascular Revascularization Medicine》2006,7(4):208-211
OBJECTIVES: We sought to compare the adequacy of paclitaxel-eluting stent (PES) and sirolimus-eluting stent (SES) expansion based on intravascular ultrasound (IVUS) imaging criteria at conventional delivery pressures. METHODS: Forty-six patients underwent SES implantation and 42 patients underwent PES implantation for de novo native coronary lesions<33 mm in length with reference lumen diameters of 2.5-3.5 mm. Stents were serially expanded with gradual balloon inflations at 14 and 20 atm. IVUS imaging was performed prior to intervention and after each balloon inflation. Stent expansion (minimal stent cross-sectional area/reference lumen cross-sectional area) was measured. Inadequate stent expansion was defined using the MUSIC criteria (all struts apposed, no tissue protrusion, and final lumen cross-sectional area>80% of the reference or >90% if minimal lumen cross-sectional area was <9 mm2). RESULTS: The baseline characteristics of the two groups were similar except for shorter lesion length, larger mean lumen cross-sectional area, larger lumen diameter, and lower plaque burden in the PES group. Stent expansion was inadequate in 80% of patients with SES versus 63% of patients with PES at 14 atm, although this was not statistically significant. After 20 atm, 48% of patients with SES remained underexpanded as compared with 35% of patients with PES. CONCLUSION: Drug-eluting stents showed significant underexpansion by MUSIC criteria at conventionally used inflation pressures. Higher balloon inflations are required especially during deployment of a SES. IVUS guidance is recommended to ensure optimal results and outcomes with both stents. 相似文献