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61.

BACKGROUND:

An elevated level of homocysteine (Hcy) has been shown to be a cardiovascular risk factor in the majority of research studies. Recently, it was found to be associated with new risk factors such as inflammatory markers.

OBJECTIVES:

To investigate the distribution of plasma total Hcy (tHcy) and the levels of inflammatory markers in patients with acute coronary syndrome (ACS), and to evaluate the association between these parameters and the severity of the disease.

METHODS:

A total of 122 patients with ACS and 80 control subjects were recruited from the cardiac intensive care unit of the Military Hospital of Tunis, Tunisia. Lipid profile and the levels of tHcy, high-sensitivity C-reactive protein (HsCRP), interleukin (IL)-6, IL-8, IL-1β and tumour necrosis factor-alpha (TNFα) were determined for all participants. The distribution of these parameters were compared between groups and according to the number of diseased vessels in patients with ACS.

RESULTS:

ACS patients had significantly elevated levels of tHcy (P<0.01), HsCRP (P<0.001), IL-6 (P<0.001), TNFα (P<0.001), folates (P<0.05) and vitamin B12 (P<0.001), but lower high-density lipoprotein cholesterol (P<0.05) levels. The analysis of the association between these parameters and the number of diseased vessels showed significant differences in tHcy, HsCRP, IL-6 and TNFα, with positive correlations. Significantly negative correlations were found between the number of diseased vessels and folate (r=−0.34; P<0.01), and vitamin B12 (r=−0.22; P<0.01).

CONCLUSION:

Elevated levels of tHcy, IL-6, TNFα and HsCRP appear to be associated with a greater number of diseased arteries and, consequently, the severity of coronary artery disease.  相似文献   
62.
Background: Osteoporosis (OP) is a growing health problem not only in women but also in men. Subjects and methods: This study was carried out on 100 healthy men, age range 30–65 years (mean ± SD, 44.65 ± 8.3). All were randomly recruited from Assiut city during the period January 2005 to January 2006. Complete clinical history included occupational history, smoking habit, physical activity and calcium intake. Complete clinical examination and anthropometric measurments were done. Laboratory investigations for serum calcium, phosphorus and osteocalcin were performed. Bone mineral density (BMD) was measured by calcaneal ultrasound. Results: Sixty‐three percent of participants had normal BMD, 37% had low BMD, (26% had quantitative bone ultrasound [QUS] T‐score –1 to –2.5 and 11% had QUS T‐score ≤ –2.5). Smoking and low physical activity were risk factors for low BMD. Significant positive correlations were found between BMD and body mass index, serum calcium, and osteocalcin and negative correlation with phosphorus. We concluded that low BMD occurs with high frequency in Egyptian men. Smoking, physical inactivity and low body index are significant risk factors. Low serum calcium, low serum osteocalcin and high serum phosphorus are biochemical risk factors of low BMD in males.  相似文献   
63.

Background

The introduction of technique of radiofrequency (RF) catheter ablation in 1990, has revolutionized management of different types of paroxysmal supraventricular tachycardia (PSVT). In spite of higher success rate, there were reported recurrences among different types of SVT. The aim of this study was to report the efficacy of RF ablation, its complications, recurrence rate and its predictors.

Methods

The material of this study (our 3rd registry) included patients who underwent electrophysiological study (EPS) and radiofrequency ablation of their supraventricular tachycardia in the past 5 years, starting from January 2002 to January 2007 at The Critical Care Medicine Department, Cairo University.

Results

Out of 400 pts studied, 381 (95%) had been subjected to radiofrequency ablation (RF) ablation while the remaining 19 pts (4.7%) refused ablation for fear of possible complications. Out of the 381 pts, 366 (96%) had their target tachycardia successfully terminated, from them 26 pts (7%) experienced recurrence after having successful RF ablation. Nine pts (34.6%) of total recurrence was reported in pts with AVNRT, 7 pts (26.9%) of total recurrence was reported in pts with AVRT utilizing septal accessory pathway (Rt AS and /or Rt PS AP), 4 pts (15.4%) was reported in pts with double AP, 2 pts (7.7%) of total recurrence was reported in pts with AFl, one pt (3.8%) of total recurrence was reported in cases of AT. Redo ablation have been carried out successfully in 25 pts (96.2%), and one pt (3.8%) refused ablation for fear of possible complications.

Conclusions

Although electrophysiological study and RF ablation eliminated different types of SVT. However, there may be increased incidence of recurrence among pts with AVNRT and AVRT utilizing concealed septal AP and multiple APs secondary to the complexity of AVN physiology, the critical location of septal AP, the clinical expertise, and poor electrophysiological criteria for good procedural success.  相似文献   
64.
65.
66.

Objectives

The incidence of sexually transmitted infections (STIs) and HIV infection remains high in gay, bisexual, and other men who have sex with men (MSM) in the UK, and sexualized drug use (“chemsex”) and injecting drug use (“slamsex”) may play a part in this. We aimed to characterize HIV‐positive MSM engaging in chemsex/slamsex and to assess the associations with self‐reported STI diagnoses and sexual behaviours.

Methods

Data from a 2014 survey of people attending HIV clinics in England and Wales were linked to clinical data from national HIV surveillance records and weighted to be nationally representative. Multivariable logistic regression assessed the associations of chemsex and slamsex with self‐reported unprotected anal intercourse (UAI), serodiscordant UAI (sdUAI) (i.e. UAI with an HIV‐negative or unknown HIV status partner), sdUAI with a detectable viral load (>50 HIV‐1 RNA copies/mL), hepatitis C, and bacterial STIs.

Results

In the previous year, 29.5% of 392 sexually active participants engaged in chemsex, and 10.1% in slamsex. Chemsex was significantly associated with increased odds of UAI [adjusted odds ratio (AOR) 5.73; < 0.001], sdUAI (AOR 2.34; < 0.05), sdUAI with a detectable viral load (AOR 3.86; < 0.01), hepatitis C (AOR 6.58; < 0.01), and bacterial STI diagnosis (AOR 2.65; < 0.01). Slamsex was associated with increased odds of UAI (AOR 6.11; < 0.05), hepatitis C (AOR 9.39; < 0.001), and bacterial STI diagnosis (AOR 6.11; < 0.001).

Conclusions

Three in ten sexually active HIV‐positive MSM engaged in chemsex in the past year, which was positively associated with self‐reported depression/anxiety, smoking, nonsexual drug use, risky sexual behaviours, STIs, and hepatitis C. Chemsex may therefore play a role in the ongoing HIV and STI epidemics in the UK.  相似文献   
67.
Objective: The aim of this study was to determine the prevalence of low back pain (LBP) in a primary care setting population and examine its association with the symptoms of depression and somatization. Methods: This is a cross‐sectional study, utilising a survey carried out in primary health care clinics (PHCs) in Al‐Ain, United Arab Emirates (UAE). A multistage stratified sampling design was used and a representative sample of 1304 UAE nationals aged 18–65 years who attended PHC clinics for any reason were included and 1103 (84.5%) subjects agreed to participate and responded to the questionnaire during a period from June 2001 to January 2002. A specially designed questionnaire with three parts was used for the data collection: socio‐demographic information of the studied subjects, modified version of the Roland‐Morris scale for evaluating back‐related functional disability and SCL‐90 R for depression and somatization subscales was used to assess depressive and somatic symptoms. Results: Of the total number of subjects surveyed (1103), 586 (53.1%) were men and 517 (46.9%) women. The mean age was 34.9 ± 13.4 years for men and 33.5 ± 11.8 years for women. The prevalence of LBP in the studied subjects was 64.7% (95% CI, 60.7–68.5] with 46.7% among men and 53.3% among women. There were a significant differences between the subjects with LBP and without LBP with respect to gender (P < 0.001), body mass index (BMI) (P < 0.001), occupational status (P < 0.001) and living environment (P = 0.016). Functional disability was higher in patients with LBP. Young patients in aged 15–34 years, patients with preparatory/secondary educational level and students showed higher depressive symptoms. A similar pattern was found in patients with somatic symptoms. Factor analysis revealed a strong association between depression and somatization in LBP patients. Conclusions: Functional disability was higher in with LBP. Furthermore, symptoms of depression and somatization are prevalent among LBP patients.  相似文献   
68.
BACKGROUND: Photochemical methods can effectively inactivate extracellular viruses and bacteria found in blood components. Treatment of plasma with methylene blue (MB), a phenothiazine dye, and visible light inactivates enveloped viruses including HIV-1. The effects of MB- treated plasma on cellular components stored in vitro have not been well characterized. STUDY DESIGN AND METHODS: MB-treated plasma (83 microg MB/250 mL plasma) was added to single-donor platelets, stored AS- 1 red cells (RBCs), irradiated RBCs, and frozen-deglycerolized RBCs. In vitro platelet assays performed after 1 and 5 days of storage in MB- treated plasma included pH, pO2, pCO2, HCO3, platelet number, lactate dehydrogenase, glucose, osmotic recovery, and CD62 expression. RBC components were examined at specific intervals for leakage of potassium, plasma hemoglobin level, and percentage of hemolysis. Direct antiglobulin tests, osmotic fragilities, and RBC antigen stability tests were also performed on RBCs stored in MB-treated plasma. Components stored with autologous plasma or nontreated allogeneic plasma served as controls. RESULTS: Similar storage-induced changes in pH, glucose, and platelet numbers, as well as increases in lactate dehydrogenase, CD62 expression, and lactate were seen in single-donor platelets stored with MB-treated and control plasma. Platelet morphology scores and osmotic recoveries were not altered. Plasma hemoglobin and potassium and percentage of hemolysis increased equally in the various RBC components stored with MB-treated or nontreated plasma. Osmotic fragility and RBC antigen stability were not appreciably altered by MB-treated plasma. CONCLUSION: Plasma treated by MB photoinactivation can be used for in vitro resuspension and storage of platelets or RBCs, because of the lack of influence of MB-treated plasma on a variety of in vitro platelet and RBC assays.  相似文献   
69.
70.
Background: The secondary prevention of bleeding from ulcers may be improved if antisecretory drugs are able to maintain a 24-h gastric pH close to neutral. Aim: To evaluate the effect of intravenous famotidine at a conventional dose of 40 mg/day on 24-h intragastric pH in patients with a bleeding duodenal ulcer, and to determine the dose required to maintain gastric pH > 6 by use of a Gastrojet (MIC, Switzerland) device (a pH meter-controlled programmable pump). Methods: Twelve patients (nine men, three women), aged 24–78 years, admitted for a bleeding duodenal ulcer, were studied after active bleeding had stopped for at least 6 h. Gastric pH was recorded for two consecutive 24-h periods, each starting at 16.00 hours. The patients were fasted during these periods and received an infusion of 2.5 L of isotonic glucose. They were given famotidine, as a continuous i.v. infusion of 40 mg during one period, and at a rate determined by the Gastrojet during the other period (in a random sequence), with the aim of maintaining the gastric pH above 6. Results: The 24-h median (interquartile range) pH and the mean (± S.E.M.) percentage of the 24-h period with a gastric pH > 6 were both significantly higher during the Gastrojet period than during the continuous infusion: 6.4 (6.3–6.5) vs. 5.7 (2.7–6.4) (P < 0.01) and 74±5% vs. 44 ± 7% (P < 0.002), respectively. The mean dose of famotidine delivered by the Gastrojet was 172 mg (range: 101–200 mg). The entire available amount of famotidine (200 mg) was delivered in four of the 12 patients. The percentage of time at pH > 6 (mean ± S.E.M.) was significantly higher at night (22.00 to 07.00 hours) than during the rest of the day (88 ± 2 vs. 70 ± 6%; P < 0.005) and the mean quantity of famotidine delivered per hour was significantly lower during the night (6.3 ± 0.8 mg/h vs. 8.4 ± 0.5 mg/h; P < 0.02). Conclusion: We conclude that 40 mg of famotidine delivered as a continuous i.v. infusion is not sufficient to maintain gastric pH > 6 for 24 h in duodenal ulcer patients. Our study with the Gastrojet device shows that it may be possible to achieve this goal by using a much larger dose, preferably delivered during the day.  相似文献   
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