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Biomedical subjects

D Salem

Publications and source records attributed to D Salem.

At least 19 recordsLinked to original sources

alpha-1,4-Glucosidase activity in infertile oligoasthenozoospermic men with and without varicocele.

This work aimed to assess seminal alpha-1,4-glucosidase activity in infertile oligoasthenozoospermic men associated with and without scrotal varicocele. Eighty men were investigated. They were divided into three groups: group 1 (n = 20), fertile normozoospermic men; group 2 (n = 30), oligoasthenozoospermia with varicocele; and group 3 (n = 30), oligoasthenozoospermia without varicocele. The patients underwent medical history, clinical examination, conventional semen analysis and estimation of seminal plasma alpha-1,4-glucosidase activity by double-beam spectrophotometer method and serum testosterone by radioimmunoassay method. There was a significant decrease in the mean seminal alpha-1,4-glucosidase activity levels in infertile men versus controls (mean +/- SD; 7.66 +/- 0.433, 2.088 +/- 0.565, 5.384 +/- 0.85 mU ml(-1) respectively). Mean serum testosterone levels demonstrated nonsignificant differences between studied groups. Seminal alpha-1,4-glucosidase activity levels demonstrated significant correlation with sperm count, sperm motility percentage and serum testosterone in oligoasthenozoospermia with varicocele group and demonstrated nonsignificant correlation in other groups. It is concluded that varicocele-induced hypoxia is the adverse effect that causes both oligoasthenozoospermia and decreased seminal alpha-1,4-glucosidase levels.

Adult↗

Accuracy of imaging technologies in the diagnosis of acute cardiac ischemia in the emergency department: a meta-analysis.

STUDY OBJECTIVE: We sought to quantitatively evaluate the evidence on the diagnostic performance of imaging technologies (including rest and stress echocardiography and technetium-99m sestamibi scanning) for the diagnosis of acute cardiac ischemia and acute myocardial infarction in the emergency department. METHODS: We conducted a systematic review and meta-analysis of the English-language literature published between 1966 and December 1998. Both prospective and retrospective studies qualified for the assessment of diagnostic performance. Diagnostic performance was assessed by means of random-effect estimates of test sensitivity, specificity, and the diagnostic odds ratio and was summarized by using summary receiver-operating characteristic curves. RESULTS: Diagnostic accuracy was evaluated in 10 studies of rest echocardiography, 2 studies of dobutamine stress echocardiography, and 6 studies of technetium-99m sestamibi scanning. However, only 3 rest echocardiography and 5 technetium-99m sestamibi studies evaluated patients strictly in the ED setting. Patient populations were often highly selected to represent low- or moderate-risk groups. When limited to ED studies, rest echocardiography showed excellent sensitivity of 93% (95% CI, 81% to 97%) and good specificity of 66% (95% CI, 43% to 83%). The results were similar when all studies were considered, including data from reports of admitted patients and patients sent to the cardiac care unit. There was insufficient literature on stress echocardiography in the ED to properly assess the technology. Technetium-99m sestamibi scanning also showed excellent sensitivity (range, 91.5% to 100%) and good specificity (range, 49.3% to 84.4%) for acute myocardial infarction; for acute cardiac ischemia, the random-effects pooled sensitivity was 89% (95% CI, 73% to 96%), and the pooled specificity was 77% (95% CI, 63% to 87%). CONCLUSION: For selected low- and moderate-risk patient groups, echocardiography and technetium-99m sestamibi imaging appear to have very good diagnostic performance with a similar sensitivity and specificity profile. More evidence should be accumulated on their performance specifically in the ED setting.

Acute Disease↗

Diagnosing acute cardiac ischemia in the emergency department: a systematic review of the accuracy and clinical effect of current technologies.

STUDY OBJECTIVE: Acute cardiac ischemia (ACI) encompasses the diagnoses of unstable angina pectoris and acute myocardial infarction (AMI). Accurate diagnosis and triage of patients with ACI in the emergency department should increase survival for these patients and reduce unnecessary hospital admissions. METHODS: We conducted a systematic review of the English-language literature published between 1966 and December 1998 on the accuracy and clinical effect of diagnostic technologies for ACI. We evaluated prospective and retrospective studies of adult patients who presented to the ED with symptoms suggesting ACI. Outcomes were diagnostic performance (test sensitivity and specificity) and measures of clinical effect. Meta-analyses were performed when appropriate. A decision and cost-effectiveness analysis was conducted that investigated various diagnostic strategies used in the diagnosis of ACI in the ED. RESULTS: We screened 6,667 abstracts, reviewed 407 full articles, and included 106 articles articles in the main analysis. Single measurements of biomarkers at presentation to the ED have low sensitivity for AMI, although they have high specificity. Serial measurements greatly increase the sensitivity for AMI while maintaining their excellent specificity. Diagnostic technologies to evaluate ACI in selected populations, such as electrocardiography, sestamibi perfusion imaging, and stress ECG, may have very good to excellent sensitivity; however, they have not been sufficiently studied. The Goldman Chest Pain Protocol has good sensitivity (about 90%) for AMI but has not been shown to result in any differences in hospitalization rate, length of stay, or estimated costs in the single clinical effect study performed. Its applicability to patients with unstable angina pectoris has not been evaluated. The use of an Acute Cardiac Ischemia-Time-Insensitive Predictive Instrument led to the appropriate triage of 97% of patients with ACI presenting to the ED and reduced unnecessary hospitalizations. CONCLUSION: Many of the current technologies remain underevaluated, especially regarding their clinical effect. The extent to which combinations of tests may provide better accuracy than any single test needs further study.

Acute Disease↗

Accuracy and clinical effect of out-of-hospital electrocardiography in the diagnosis of acute cardiac ischemia: a meta-analysis.

STUDY OBJECTIVE: We sought to evaluate quantitatively the evidence on the diagnostic performance of out-of-hospital ECG for the diagnosis of acute cardiac ischemia (ACI) and acute myocardial infarction (AMI) and the clinical effect of out-of-hospital thrombolysis. METHODS: We conducted a systematic review and meta-analysis of the English-language literature published between 1966 and December 1998 on the diagnostic accuracy of out-of-hospital ECG and the clinical effect of out-of-hospital thrombolysis. Both prospective and retrospective studies qualified for the assessment of diagnostic performance. For clinical effect, data from prospective nonrandomized studies were synthesized separately from data from randomized trials. Diagnostic performance was assessed by using estimates of test sensitivity, specificity, and diagnostic odds ratios and was summarized by using summary receiver-operating characteristic curves. Measures of clinical effect included time savings, early ventricular function, early mortality, and long-term survival. RESULTS: Diagnostic accuracy was evaluated in 11 studies with a total of 7,508 patients. Data were available for ACI in 5 studies and for AMI in 8 studies. For ACI, the random-effects pooled sensitivity was 76% (95% CI, 54% to 89%), the specificity was 88% (95% CI, 67% to 96%), and the diagnostic odds ratio was 23 (95% CI, 6.3 to 85). The respective figures for AMI were sensitivity of 68% (95% CI, 59% to 76%), specificity of 97% (95% CI, 89% to 92%), and diagnostic odds ratio of 104 (95% CI, 48 to 224). Both in nonrandomized (n=4, total 1,531 patients) and randomized (n=9, total 6,643 patients) studies, out-of-hospital thrombolysis shortened the time from onset of symptoms to thrombolytic treatment by 40 to 60 minutes. Data on short-term ejection fraction were sparse. Hospital mortality was reduced by 16% (95% CI, 2% to 27%) among randomized trials, and a similar estimate of effect was seen in nonrandomized studies. There was no clear effect on long-term mortality, but data were sparse. CONCLUSION: Out-of-hospital ECG has excellent diagnostic performance for AMI and very good performance for ACI. Out-of-hospital thrombolysis achieves time savings and improves short-term mortality, but the effect on long-term mortality is unknown.

Acute Disease↗

Accuracy of biomarkers to diagnose acute cardiac ischemia in the emergency department: a meta-analysis.

STUDY OBJECTIVE: We sought to evaluate quantitatively the evidence on the diagnostic performance of presentation and serial biochemical markers for emergency department diagnosis of acute cardiac ischemia (ACI), including acute myocardial infarction (AMI) and unstable angina. METHODS: We conducted a systematic review and meta-analysis of the English-language literature published between 1966 and December 1998. We examined the diagnostic performance of creatine kinase, creatine kinase-MB, myoglobin, and troponin I and T testing. Diagnostic performance was assessed by using estimates of test sensitivity and specificity and was summarized by summary receiver-operating characteristic curves. RESULTS: Only 4 studies were found that evaluated all patients with ACI; 73 were found that focused only on a diagnosis of AMI. To diagnose ACI, presentation biomarker tests had sensitivities of 16% to 19% and specificities of 96% to 100%; serial biomarker tests had sensitivities of 31% to 45% and specificities of 95% to 98%. Considering only the diagnosis of AMI, presentation biomarker tests had summary sensitivities of 37% to 49% and summary specificities of 87% to 97%; serial biomarker tests had summary sensitivities of 79% to 93% and summary specificities of 85% to 96%. Variation of test sensitivity was best explained by test timing. Longer symptom duration or time between serial tests yielded higher sensitivity. CONCLUSION: The limited evidence available to evaluate the diagnostic accuracy of biomarkers for ACI suggests that biomarkers have very low sensitivity to diagnose ACI. Thus, biomarkers alone will greatly underdiagnose ACI and will be inadequate to make triage decisions. For AMI diagnosis alone, multiple testing of individual biomarkers over time substantially improves sensitivity, while retaining high specificity, at the expense of additional time. Further high-quality studies are needed on the clinical effect of using biomarkers for patients with ACI in the ED and on optimal timing of serial testing and in combination with other tests.

Acute Disease↗

Knot security in simple sliding knots and its relationship to rotator cuff repair: how secure must the knot be?

We sought to determine which simple sliding knot configurations would have adequate strength for rotator cuff repair. Four knot configurations were tied with both No. 1 polydioxanone suture and No. 2 Ethibond suture (Ethicon, Somerville, NJ) using 3 different tying techniques: hand-tie, standard knot pusher, and cannulated double-diameter knot pusher. The knots were then tested to failure on a materials testing system. The weakest standard knot configuration was S=S=S=S. The other 3 knot configurations (S//S//S//S, SxSxSxS, and S//xS//xS//xS) generally failed in the 35 to 50 N range. Ultimate strength in this range can be shown to be adequate to withstand, without suture failure, a maximal contraction of a repaired rotator cuff tear within the rotator crescent, assuming certain conditions are met (suture anchors placed 1 cm apart, 2 sutures per anchor). More complex knots are not necessary for adequate knot security. However, the same configuration with only 1 suture per anchor will not be strong enough because the suture will fail under maximum physiological load. This study shows that we can predict the adequacy of a given knot configuration under maximum physiological loading conditions.

Arthroscopy↗

Giving and receiving help: interpersonal transactions in mutual-help meetings and psychosocial adjustment of members.

The helping transactions that occur in group meetings have been theorized to be important therapeutic mechanisms within mutual-help (or self-help) groups. Hypothesized links between giving and receiving help and psychosocial adjustment were examined in a mutual-help group for individuals with serious mental illness (GROW). Participants' adjustment was assessed at two time points and helping behaviors were measured with observational coding of weekly group interactions during the period between assessments. Frequencies of helping behaviors were used to predict Time 2 adjustment after controlling for initial adjustment. Consistent with the helper therapy principle, giving help to others predicted improvements in psychosocial adjustment; giving advice was a unique predictor. Total amount of help received was not associated with adjustment, but receiving help that provided cognitive reframing was associated with better social adjustment. A predicted interaction suggested that receiving help was related to better functioning when members experienced high levels of group integration.

Adaptation, Psychological↗

Possible role of Schistosoma mansoni infection in male hypogonadism.

Schistosomiasis has been suggested to decrease the reproductive potential or castrate both invertebrate and vertebrate hosts. Furthermore, schistosomiasis may cause anatomic anomalies of the reproductive organs responsible for permanent or reversible infertility. To specify the effect of schistosomiasis on gonadal functions, production of testosterone (TS), leutinizing hormone (LH) and estradiol (E2) in Egyptian men infected with schistosomiasis were studied. All participants were tested for the following parameters: Clinical examination and diagnostic, semen, haematological and liver function tests and blood level of IL-2. The mean TS levels were at the lowest limit of normal range for liver cirrhotic patients. Mean E2 levels were increased in all patients, but patients with liver cirrhosis-related schistosomiasis had higher E2 levels. Linear regression analysis showed that the sex hormone levels correlated best with the patient's liver function parameters. The present data suggest that a sex hormone imbalance plays a role in patients with liver cirrhosis due to the inhibitory effects of schistosomiasis on gonadal functions.

Animals↗

Loop security as a determinant of tissue fixation security.

Secure arthroscopic repair of rotator cuff tears and Bankart lesions requires tight knots (knot security). Equally important, but usually overlooked, is the tightness of the suture loop (loop security). This study compared loop security in knots tied with No. 1 PDS suture using three different methods: (1) hand-tied, (2) single-hole standard knot pusher, and (3) cannulated double-diameter knot pusher. The results of this study show that the double-diameter knot pusher maintained tight suture loops that were equivalent in circumference to hand-tied loops and were significantly tighter than suture loops tied with a standard single-hole knot pusher. This study highlights the fact that loop security is equally important to knot security in tissue fixation.

Arthroscopy↗

Baseline quality of life as a predictor of mortality and hospitalization in 5,025 patients with congestive heart failure. SOLVD Investigations. Studies of Left Ventricular Dysfunction Investigators.

This study examined the independent relation of health-related quality of life (HRQL) to mortality and congestive heart failure (CHF)-related hospitalizations in patients with an ejection fraction of < 0.35 followed for a mean of 36.5 months. A brief HRQL questionnaire was administered at baseline to patients randomized to placebo or enalapril in the Studies of Left Ventricular Dysfunction (SOLVD) trial. Participants had an ejection fraction of < 0.35 and either symptomatic CHF (treatment trial, n = 2,465) or asymptomatic CHF (prevention trial, n = 2,560). Baseline assessment of HRQL predicted mortality and CHF-related hospitalizations in symptomatic and asymptomatic patients randomized to enalapril and placebo treatment. Domains that were the stronger univariate predictors of mortality and CHF-related hospitalizations were activities of daily living (relative risk [RR] for mortality: 1.163, p < 0.000; for hospitalization: 1.215, p < 0.000), general health (RR for mortality: 1.205, p < 0.000; for hospitalization: 1.188, p < 0.000), and social functioning (RR for mortality 1.098, p < 0.000; for hospitalization: RR 1.156, p < 0.000). In the multivariate model, activities of daily living (RR for mortality 1.41, p < 0.000; for hospitalization: RR 1.43, p < 0.002), general health (RR for mortality 1.21, p < 0.000; for hospitalization RR 1.16, p < 0.013) and heart failure symptoms (RR for mortality 1.02, p < 0.025; for hospitalization RR 1.03, p < 0.004) were found to be independent risk factors. HRQL independently predicted mortality and CHF-related hospitalizations after adjustment for ejection fraction, age, treatment, and New York Heart Association classification in patients with an ejection fraction of < 0.35, randomized to enalapril and placebo treatment. HRQL provides additional clinical information regarding disease course and outcome that is not captured by traditional indexes of clinical status.

Activities of Daily Living↗

Sudden cardiac death and the 'athlete's heart'.

OBJECTIVES: To review the current literature pertaining to the cardiovascular adaptations to exercise and the impact on the physical examination, the electrocardiogram, and the echocardiogram, and to distinguish those physiologic changes from pathologic conditions associated with sudden cardiac death in athletes. DATA SYNTHESIS: Specific cardiovascular adaptations occur in response to regular physical exercise. The extent of these changes depend on the type and duration of exercise as well as the gender of the athlete. These cardiac adaptations are morphologically different from those conditions associated with sudden cardiac death. In the athlete younger than 35 years, hypertrophic cardiomyopathy is the most common cardiac condition associated with sudden death. Right ventricular dysplasia, idiopathic left ventricular hypertrophy, coronary anomalies, premature atherosclerosis, and Marfan syndrome compose the majority of the remaining causes of sudden cardiac death in athletes. In the athlete older than 35 years, coronary atherosclerosis is the leading cause of sudden death followed by those conditions responsible for sudden death in the younger athlete. Despite this, regular exercise before or following a myocardial infarction provides a protective effect with respect to overall mortality, cardiovascular mortality, and fatal reinfarction rates. CONCLUSIONS: Cardiovascular adaptation to regular physical exercise leads to morphologic changes in the myocardium that influence the cardiac examination, the electrocardiogram, and the echocardiogram. Knowledge and recognition of those changes can allow the clinician to distinguish normal physiologic changes from cardiac abnormality. Proper detection of athletes at high risk for sudden cardiac death and abstention from vigorous physical activity in these athletes may prevent sudden death.

Adaptation, Physiological↗

Effect of enalapril on myocardial infarction and unstable angina in patients with low ejection fractions.

An association between raised renin levels and myocardial infarction has been reported. We studied the effects of enalapril, an angiotensin-converting enzyme (ACE) inhibitor, on the development of myocardial infarction and unstable angina in 6797 patients with ejection fractions < or = 0.35 enrolled into the two Studies of Left Ventricular Dysfunction (SOLVD) trials. Patients were randomly assigned to placebo (n = 3401) or enalapril (n = 3396) at doses of 2.5-20 mg per day in two concurrent double-blind trials with the same protocol. Patients with heart failure entered the treatment trial (n = 2569) and those without heart failure entered the prevention trial (n = 4228). Follow-up averaged 40 months. In each trial there were significant reductions in the number of patients developing myocardial infarction (treatment trial: 158 placebo vs 127 enalapril, p < 0.02; prevention trial: 204 vs 161 p < 0.01) or unstable angina (240 vs 187 p < 0.001; 355 vs 312, p < 0.05). Combined, there were 362 placebo group patients with myocardial infarction compared with 288 in the enalapril group (risk reduction 23%, 95% CI 11-34%; p < 0.001). 595 placebo group patients developed unstable angina compared with 499 in the enalapril group (risk reduction 20%, 95% CI 9-29%, p < 0.001). There was also a reduction in cardiac deaths (711 placebo, 615 enalapril; p < 0.003), so that the reduction in the combined endpoint of deaths, myocardial infarction, and unstable angina was highly significant (20% risk reduction, 95% CI 14-26%; p < 0.0001). Enalapril treatment significantly reduced myocardial infarction, unstable angina, and cardiac mortality in patients with low ejection fractions.

Angina, Unstable↗

Syncope: current diagnostic evaluation and management.

OBJECTIVE: To provide a comprehensive review of the causes, current diagnostic evaluation, and treatment of syncope. DATA IDENTIFICATION: New data and knowledge in this evolving field were critically analyzed by doing a MEDLINE search on syncope supplemented by selective review of English language literature citations in the Index Medicus before 1980. STUDY SELECTION: We reviewed approximately 200 published articles on syncope and closely related topics as well as using our own clinical experience. We selected articles if they addressed the pathophysiology of syncope, classification and causes, differential diagnosis, noninvasive and invasive evaluation, and current therapy. RESULTS OF DATA SYNTHESIS: Syncope is a common clinical problem, occurring in 30% to 50% of the adult population. The prognosis for syncope depends on its cause. Cardiac syncope has the worst prognosis and therefore mandates thorough evaluation and prompt treatment. Diagnostic evaluation is made difficult by the transient nature of the episodes and the many causes. Noninvasive testing reveals the cause of syncope in approximately 50% of cases. More extensive evaluation, including invasive electrophysiologic studies, has assumed a larger role in defining the cause of syncope in selected patients with structural heart disease in whom a noninvasive evaluation has been nondiagnostic. Recently tilt-table studies have been proposed as a clinically useful noninvasive test for vagally mediated syncope. CONCLUSIONS: A rational stepwise diagnostic and therapeutic approach to patients with syncope can be developed by initially doing a careful history and physical examination followed by a noninvasive evaluation and selective use of additional, more specialized or invasive tests. Future research should focus on defining the validity and utility of current diagnostic testing in syncope and on exploring further the pathophysiology of patients with recurrent, unexplained syncope.

Cardiovascular Diseases↗

Calcium homeostasis in untreated pulmonary tuberculosis. I--Basic study.

This study has been done to evaluate serum calcium, phosphorus (P), magnesium, parathyroid hormone (PTH), calcitonin (CT), and cyclic adenosine monophosphate (cAMP) in recently diagnosed pulmonary tuberculous patient, (n = 61) and the results were compared with the healthy control group (n = 22). Twenty four hours urine was collected for estimation of these electrolytes as well as cAMP. Nephrogenous cAMP (NcAMP) was calculated. Serum Ca and PTH were significantly reduced in TB groups, but CT was elevated. Serum Mg, P and cAMP as well as urinary Ca and Mg in TB groups were similar to that of the control group. Urinary P, cAMP NcAMP were increased in patient groups compared with the control. The reduced serum Ca could be due to impaired intestinal absorption of Ca, or deficient intake as a result of anorexia, decreased plasma albumin, decreased active metabolites of vitamin D or elevated CT. The rise in serum CT in TB might be due to increased CT secreted from the bronchial K-cells. Increased NcAMP might be due to the associated increase in serum antidiuretic hormone (ADH). The elevated urinary P in TB could be attributed to tissue breakdown, decreased serum PTH or increased CT.

Adult↗