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581.

Background  

Methamphetamine (MA) use continues to be a major public health concern in many urban settings. We sought to assess potential relationships between MA use and individual, social, and structural HIV vulnerabilities among sexual minority (lesbian, gay, bisexual or transgendered) drug users.  相似文献   
582.
INTRODUCTION: the deadly threat of systemic infections with coagulase negative Staphylococcus lugdunensis despite an appropriate antibiotic therapy has only recently been recognized. The predominant infectious focus observed so far is left-sided native heart valve endocarditis, but bone and soft tissue infections, septicaemia and vascular catheter-related bloodstream infections have also been reported. We present a patient with a fatal Staphylococcus lugdunensis septicaemia following zoster bacterial superinfection of the pelvic region. case presentation: a 71-year old male diagnosed with IgG kappa plasmocytoma presented with a conspicuous weight loss, a hypercalcaemic crisis and acute renal failure. After initiation of haemodialysis treatment his condition improved rapidly. However, he developed a varicella-zoster virus infection of the twelfth thoracic dermatome requiring intravenous acyclovir treatment. Four days later the patient presented with a fulminant septicaemia. Despite an early intravenous antibiotic therapy with ciprofloxacin, piperacillin/combactam and vancomycin the patient died within 48 hours, shortly before the infective isolate was identified as Staphylococcus lugdunensis by polymerase chain reaction. CONCLUSION: despite S. lugdunensis belonging to the family of coagulase-negative staphylococci with an usually low virulence, infections with S. lugdunensis may be associated with an aggressive course and high mortality. This is the first report on a Staphylococcus lugdunensis septicaemia following a zoster bacterial superinfection of the pelvic region.  相似文献   
583.
The Angelchik prosthesis is an incomplete doughnut-shaped device composed of silicone elastomer used in the treatment of gastro-oesophageal reflux disease (GORD). It is used to encircle the lower oesophagus at the gastro-oesophageal junction (GOJ). The ease of the operation led to the insertion of over 25,000 such prostheses world-wide. However, a variety of major complications including intractable dysphagia, prosthesis migration and gastric erosion required a quarter of these devices to be removed. Development of adenocarcinoma in patients with Angelchik prosthesis is a rare occurrence. This article describes two patients who developed adenocarcinoma above their prosthesis and whose cardio-oesophagectomy was technically challenging due to the formation of a dense inflammatory capsule around the prosthesis. Our surgical approach to curative oesophageal resection with the Angelchik prosthesis in situ is also discussed.  相似文献   
584.

Objective

The aim of the study was to evaluate the feasibility of a prehospital trial comparing hypertonic saline and dextran (HSD) with normal saline (NS) in blunt head injury patients.

Design

The study used a double blind randomized trial.

Setting

The study was conducted in air and land emergency medical services and 2 trauma centers serving a population of 4 million people.

Patients

The study population consisted of head injured, blunt trauma adult patients with a Glasgow Coma Scale of lower than 9.

Interventions

We used 250 mL of HSD vs NS given within 4 hours of the accident.

Measurements

The specific objectives were to assess protocol-related logistical issues, randomization, HSD safety, and follow up rates and to obtain survival and neurocognitive end point estimates.

Main Results

Of 132 eligible patients, 113 were randomized. Nineteen eligible patients were missed because of lack of time (9 [22%]), paramedic discretion (3 [7%]), the paramedic forgot (6 [15%]), and the paramedic refused (1 [2%]). Randomization compliance was 96% (109/113). Four randomized cases met exclusion criteria: penetrating trauma (1), cardiac arrest (2), and fall from standing (1). Three randomized patients were excluded from the final analysis: 2 patients received less than 50 mL of study solution due to an interstitial intravenous line and 1 lost randomization identification. Fifty patients (47%) were randomized to HSD and 56 (53%) to NS. Mean injury severity score was 32.7 for HSD and 32.6 for NS. There was no difference in length of stay, Sequential Organ Failure Assessment maximum, Multiple Organ Dysfunction Score maximum, delta Multiple Organ Dysfunction Score, or Apache scores. Initial head scans scored 3 or higher by Marshall classification for 12 HSD and 11 NS patients. Zero adverse events occurred, and follow-up for the primary outcome was 100%. Alive at 30 days for HSD and NS, respectively, was 70% (35/50) and 75% (42/56) and at discharge was 68% (34/50) and 73% (41/56). Only 49.3% (37/77) of surviving patients consented to follow-up at 4 months and 89% (33/37) completed the assessment. Disability rating scale (median, interquartile range) was 3 (0, 6) for HSD and was 0 (0, 6) for NS. Glasgow Outcome Scale Evaluation was higher than 4 for HSD (12/12 [100%]) and NS (15/21 [72%]). Functional Independence Measure (mean, SD) was 62 (37) for HSD and 80 (32) for NS.

Conclusions

It is feasible to conduct a prehospital randomized controlled trial with HSD for treatment of blunt trauma patients with head injuries; however, consent for neurofunctional outcomes in this cohort is problematic and threatens the feasibility of definitive trials using these potentially meaningful end points.  相似文献   
585.
Taylor A, Wang D, Patel K, Whittall R, Wood G, Farrer M, Neely RDG, Fairgrieve S, Nair D, Barbir M, Jones JL, Egan S, Everdale R, Lolin Y, Hughes E, Cooper JA, Hadfield SG, Norbury G, Humphries SE. Mutation detection rate and spectrum in familial hypercholesterolaemia patients in the UK pilot cascade project. Cascade testing using DNA‐mutation information is now recommended in the UK for patients with familial hypercholesterolaemia (FH). We compared the detection rate and mutation spectrum in FH patients with a clinical diagnosis of definite (DFH) and possible (PFH) FH. Six hundred and thirty‐five probands from six UK centres were tested for 18 low‐density lipoprotein receptor gene (LDLR) mutations, APOB p.Arg3527Gln and PCSK9 p.Asp374Tyr using a commercial amplification refractory mutation system (ARMS) kit. Samples with no mutation detected were screened in all exons by single strand conformation polymorphism analysis (SSCP)/denaturing high performance liquid chromatography electrophoresis (dHPLC)/direct‐sequencing, followed by multiplex ligation‐dependent probe amplification (MLPA) to detect deletions and duplications in LDLR.The detection rate was significantly higher in the 190 DFH patients compared to the 394 PFH patients (56.3% and 28.4%, p > 0.00001). Fifty‐one patients had inadequate information to determine PFH/DFH status, and in this group the detection rate was similar to the PFH group (25.5%, p = 0.63 vs PFH). Overall, 232 patients had detected mutations (107 different; 6.9% not previously reported). The ARMS kit detected 100 (44%) and the MLPA kit 11 (4.7%). Twenty‐eight (12%) of the patients had the APOB p.Arg3527Gln and four (1.7%) had the PCSK9 p.Asp374Tyr mutation. Of the 296 relatives tested from 100 families, a mutation was identified in 56.1%. In 31 patients of Indian/Asian origin 10 mutations (two previously unreported) were identified. The utility of the ARMS kit was confirmed, but sequencing is still required in a comprehensive diagnostic service for FH. Even in subjects with a low clinical suspicion of FH, and in those of Indian origin, mutation testing has an acceptable detection rate.  相似文献   
586.
587.
Several studies indicate that in utero and perinatal exposure to polychlorinated biphenyls (PCBs) induces adverse reproductive effects, but it remains unclear whether such effects may be transmitted to subsequent generations. We therefore investigated the association between maternal exposure to PCBs and reproductive health in male and female offspring over three generations. Mouse dams were fed 0, 1, 10, and 100 μg/kg/day of a PCB mixture (101 + 118) during pregnancy and lactation. PCB levels were measured in the tissues of both dams and offspring. PCB concentrations at all doses investigated were greater in the offspring than in the dams (p ≤ 0.0001) confirming that the progeny were exposed as a result of maternal exposure. In F1 offspring, exposure to PCBs resulted in reductions in (1) testis weight (p ≤ 0.05) and seminiferous tubule diameter (p ≤ 0.05), (2) sperm viability (p ≤ 0.0001) and developmental capacity (p ≤ 0.05), (3) ovary weight (p ≤ 0.05), (4) oocyte developmental capacity (p ≤ 0.05), and (5) increased follicular atresia (p ≤ 0.0001). In females, adverse effects were observed only in the F1 animals. In contrast, male offspring exhibited reduced sperm viability and altered seminiferous tubule distribution up to the third generation, showing intergenerational transmission. In summary, our data indicate that exposure to PCBs at the time of gonadal sex determination perturbed, significantly, the reproductive physiology of male and female offspring in adulthood. Furthermore, male reproductive deficiencies may be observed in at least two further generations. These findings have significant implications for reproductive health and fertility of animals and humans.  相似文献   
588.
学术背景:一般认为中枢神经系统损伤后,由于内在的再生能力差和外在环境抑制,损伤轴突不能再生。近年来研究证实脊髓损伤后采用一些改变其局部环境的方法,能促使损伤神经修复、再生及恢复脊髓部分神经功能。目的:移植的嗅鞘细胞通过加速轴突穿过受损脊髓的区域,从而恢复部分神经功能,有必要对嗅鞘细胞移植治疗脊髓损伤的基础和临床研究现状进行深入认识。检索策略:由该论文的研究人员应用计算机检索Pubmed数据库1994-01/2007-07的相关文献,检索词"spinal cord injury,Olfactory Ensheathing Cells,Neumtrophic Factors",并限定文章语言种类为English。同时计算机检索中国期刊全文数据库2000-01/2007-07的相关文献,检索词"嗅鞘细胞,脊髓损伤",并限定文章语言种类为中文。共检索到76篇文献,对资料进行初审,纳入标准:①文章所述内容应与嗅鞘细胞移植治疗脊髓损伤密切相关。②同一领域选择近期发表或在权威杂志上发表的文章。排除标准:①重复性研究。②Meta分析。文献评价:文献的来源主要是通过对嗅鞘细胞移植治疗脊髓损伤方面内容进行汇总分析。所选用的34篇文献中,4篇为综述,其余均为临床或基础实验研究。资料综合:①大量的基础和临床研究显示:脊髓损伤后采用一些改变其局部环境的方法,能促使损伤神经修复、再生和恢复脊髓部分冲经功能。在这些方法中,嗅鞘细胞被认为是治疗脊髓损伤最有前景的方法之一。②嗅鞘细胞具有许旺细胞和星形胶质细胞相似的特征,在其膜上表达出很多与细胞黏合和轴突生长相关的分子,还能分泌大量不同种类的神经营养和支持因子;实验证实嗅鞘细胞移植入各种脊髓损伤的模型表现出促进脊髓轴突再生的能力。③临床研究证实,嗅鞘细胞移植对脊髓损伤患者的脊髓神经功能恢复具有帮助作用,且安全性有保障。结论:采用嗅鞘细胞移植治疗脊髓损伤已被公认为非常有效且前景广阔的治疗方法之一。目前采用嗅鞘细胞移植治疗的晚期脊髓损伤患者为数尚少,还需要进一步观察研究其最终恢复程度和临床安全性;此外仍需探讨如何提高脊髓神经功能恢复的程度。  相似文献   
589.
BACKGROUND: The time-dependent association between metabolic syndrome and risk of chronic kidney disease (CKD) is not clear. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: The study cohort was composed of 10,685 healthy men without CKD, hypertension, or diabetes who participated in a health-checkup program at a large work site. PREDICTOR: Metabolic syndrome. OUTCOMES & MEASUREMENTS: CKD was defined as an estimated glomerular filtration rate (GFR) less than 60 mL/min/1.73 m(2). A standard Cox proportional hazards model and a time-dependent Cox model were used to calculate adjusted hazard ratios (HRs) in the CKD model. RESULTS: During 40,616.8 person-years of follow-up, 291 incident cases of CKD developed; 787 patients (7.4%) had metabolic syndrome at baseline and 1,444 (14.4%) developed incident metabolic syndrome during follow-up. After adjustment for age, baseline GFR, gamma-glutamyltransferase level, and uric acid level, metabolic syndrome at baseline was associated with a significantly increased risk of CKD (HR, 1.99; 95% confidence interval, 1.46 to 2.73). Metabolic syndrome over time as a time-dependent variable also predicted the development of CKD (HR, 1.83; [corrected] 95% confidence interval, 1.34 to 2.49) [corrected] The relationship between metabolic syndrome and incident CKD remained significant, even after further adjustment for the homeostasis model assessment of insulin resistance, high-sensitivity C-reactive protein level, current smoking, alcohol consumption, or regular exercise. In addition, there were graded relationships between number of metabolic syndrome traits or quintile of homeostasis model assessment of insulin resistance over time as a time-dependent variable and risk of CKD. Both increased triglyceride and low high-density lipoprotein cholesterol levels among metabolic syndrome traits were associated with significantly increased risk of CKD. These results were effectively unchanged, even after additional adjustment for incident hypertension and incident diabetes. LIMITATIONS: Estimated GFR was used instead of a directly measured GFR to define CKD. CONCLUSION: Metabolic syndrome is an independent risk factor for the development of CKD in Korean men without hypertension or diabetes, even with changes in status of metabolic syndrome over time.  相似文献   
590.
The administration of L-cysteine (500 mg/kg i.p.) 30 min before and 5 h after the administration of (+)-amphetamine sulfate markedly attenuated the persistent decreases in striatal dopamine (DA), dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in rats one week after the administration of a single dose of amphetamine (9.2 mg/kg i.p.) to iprindole-treated animals and in mice one week after the last of four daily injections of amphetamine (30 mg/kg i.p.). Cysteine prevented the persistent decreases in striatal serotonin (5HT) and 5-hydroxyindoleacetic acid (5HIAA) one week after the administration of p-chloroamphetamine to rats, but failed to alter the persistent decreases in striatal DA, DOPAC and HVA in mice one week after the last of four daily doses of MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, 30 mg/kg s.c.). The results suggest that the mechanisms by which amphetamine and p-chloroamphetamine, but not MPTP, produce persistent depletions of striatal monoamines involve the generation of neurotoxic electrophilic intermediates which can be inactivated by the administration of cysteine.  相似文献   
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