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Biomedical subjects

S Melamed

Publications and source records attributed to S Melamed.

At least 55 records · Page 3Linked to original sources
PubMed1997

Occupational physicians in Israel: work structure, job and personal characteristics, and job satisfaction.

This study concerns psychosocial factors among Israeli occupational physicians. Eighty-one participants (specialists, residents, and general practitioners) responded anonymously to questionnaires assessing activities demanded by the job, satisfaction from these activities, negative and positive job characteristics, job involvement, and global job satisfaction. There was little overlap between the most frequent activities (fitness for work assessments, statutory health surveillance examinations, and administrative tasks) and the activities the physicians enjoyed most (professional consultations and participation in continuing medical education (CME) activities, fitness for work assessments, and scheduled workplace visits). The most powerful predictors of job satisfaction were job involvement and satisfaction with job activities. Job involvement was related to job characteristics. The findings provide various insights for promoting job involvement and satisfaction, such as improving communication, social support, and feedback within the occupational health system and finding ways to increase quality.

Attitude of Health Personnel↗
PubMed1997

Laser scanning tomography and angiography of the optic nerve head for the diagnosis and follow-up of glaucoma.

New imaging technologies allow us to detect and follow very subtle changes of the structure and perfusion of the optic nerve head. Two of these technologies, confocal scanning laser ophthalmoscopy and confocal tomographic angiography are reviewed, focusing on new data and advances reported in the past year. These and other technologies (eg, nerve fiber layer polarimetry, optical coherent topography, and laser doppler flowmetry) will enhance the ability to diagnose and monitor glaucomatous disc damage.

Fluorescein Angiography↗
PubMed1997

Intraocular pressure increments after cataract extraction in glaucomatous eyes with functioning filtering blebs.

BACKGROUND AND OBJECTIVE: The effects of cataract extraction on intraocular pressure (IOP) were studied in glaucoma patients who had previously undergone trabeculectomy. PATIENTS AND METHODS: The files of 22 patients with 25 glaucomatous eyes with functioning filtering blebs who underwent cataract extraction were retrospectively reviewed. All patients had undergone pretrabeculectomy examination and had at least 18 months of follow-up after cataract surgery. Visual acuity, IOP, status of the filtering bleb, and the number of medications applied were recorded. RESULTS: The mean increase in IOP was 3.63 mm Hg, 3.84 mm Hg, 5.4 mm Hg, and 2.8 mm Hg at 3, 6, 12, and 18 months after cataract extraction, respectively. This elevation was statistically significant 3 months postoperatively (P < .001) and remained relatively constant thereafter. The postoperative IOP was still significantly lower than the pretrabeculectomy IOP (P < .001). CONCLUSIONS: Cataract extraction through corneal incisions in patients with functioning filtering blebs is followed by an increase in IOP. Cataract surgery in these patients does not neutralize the pressure-lowering effect achieved by the trabeculectomy, but it tends to elevate the post-trabeculectomy baseline pressure.

Aged↗
PubMed1997

Fornix-based trabeculectomy with mitomycin-C.

BACKGROUND AND OBJECTIVE: Mitomycin-C (MMC) has been shown to improve the surgical success of trabeculectomy; however, the advantages of MMC have been evaluated almost entirely as an adjunct to limbal-based trabeculectomy. This study evaluated the efficacy and safety of fornix-based trabeculectomy with MMC for glaucomatous patients. PATIENTS AND METHODS: Between January 1993 and April 1995, 71 patients underwent fornix-based trabeculectomy with topical application of 0.4 mg/ml of MMC for 3 minutes. The conjunctiva-Tenon's capsule flap was spread over the limbus and sutured in order to create a visible crease with a water-tight closure. The mean follow-up time was 14.5 months. RESULTS: The mean intraocular pressure (IOP) before surgery was 32.4 +/- 9.7 mm Hg. The average postoperative IOP was 14.04 +/- 9.57 mm Hg. An IOP of 20 mm Hg or less was observed in 57 eyes (80%). Postoperatively, 37 eyes (52%) required no additional medical therapy. One month after surgery, only 2 patients had wound leakage with hypotony and choroidal detachment. Two eyes (3%) had suprachoroidal hemorrhage with loss of vision. A conjunctival "buttonhole" occurred in 2 eyes (3%), but only 1 persisted more than a month. CONCLUSIONS: Fornix-based trabeculectomy using intraoperative application of 0.4 mg/ml of MMC for 3 minutes was found to be as safe and effective as limbal-based trabeculectomy with MMC.

Adult↗
PubMed1996

Early postoperative intraocular pressure pattern in glaucomatous and nonglaucomatous patients.

PURPOSE: To evaluate intraocular pressure (IOP) changes in the 24 hours following cataract extraction in glaucomatous and nonglaucomatous patients. SETTING: General Eye Service and Glaucoma Service of the Goldschleger Eye Institute, Tel Hashomer, Israel. METHODS: Twenty-six nonglaucomatous patients and 13 glaucomatous patients scheduled for routine cataract extraction and intraocular lens implantation were evaluated. In each patient, IOP was measured before cataract surgery and every 4 hours for 24 hours postoperatively. Thirteen of the nonglaucomatous patients were randomly treated with one drop of timolol maleate at the end of surgery (NG-T group). The other 13 nonglaucomatous patients (NG group) and all glaucoma patients (G group) were not treated. RESULTS: In the NG group, mean preoperative IOP was 13.9 mm Hg. Following surgery, IOP rose steadily to 22.2 mm Hg at 12 hours; it returned to almost presurgical levels at 24 hours. The IOP exceeded 35 mm Hg in only one patient. In the NG-T group, mean preoperative IOP was 16.5 mm Hg and increased to 21.2 mm Hg at 12 hours. The IOP returned to almost presurgical levels at 24 hours. In the G group, mean IOP was 18.8 mm Hg preoperatively and rose to 29.9 mm Hg at 8 hours after surgery. In seven eyes the IOP exceeded 35 mm Hg. COMMENTS: Our findings of elevated IOP emphasize the need for prophylactic treatment (medical or combined cataract and glaucoma surgery) to prevent IOP spikes in high-risk patients.

Acetazolamide↗
PubMed1996

Usefulness of the protection motivation theory in explaining hearing protection device use among male industrial workers.

The present study examined the usefulness of personal variables: noise annoyance, and components of the protection motivation theory (R. W. Rogers, 1983) along with social-organizational factors in explaining hearing protection device (HPD) use among Israeli manufacturing workers. Participants were 281 men exposed to harmful noise levels for which routine HPD use is required by regulation. In practice, 3 HPD user groups were identified: nonusers (n = 38), occasional users (n = 125), and regular users (n = 118). HPD use was objectively verified. HPD use was primarily related to the personal variables but not to management pressure, coworker pressure, or family support. The most powerful predictors of HPD use were perceived self-efficacy (for long-term HPD use), perceived susceptibility (to hearing loss), and noise annoyance, together explaining 48% of the outcome variance. These findings have implications for interventions aimed at motivating workers to use HPDs regularly.

Adolescent↗
PubMed1996

Hostility and hearing protection behavior: the mediating role of personal beliefs and low frustration tolerance.

The authors examined whether hostility would negatively be associated with occupational health behavior, namely, the use of hearing protection devices (HPDs). Also examined as possible mediators were the protection motivation theory (PMT) components and low frustration tolerance (LFT). Participants were 226 male industrial workers, all exposed to potentially hearing-damaging noise. Hostility was negatively related to HPD use. It moderately correlated with the PMT components: negatively with perceived susceptibility, severity, effectiveness, and self-efficacy and positively with perceived barriers. Hostility correlated highly with LFT. Regression analyses confirmed the mediating role of perceived barriers, low self-efficacy, and LFT in the negative relationship between hostility and the use of HPDs. Thus, intrapsychic characteristics of hostile people may be significant for hearing protection behavior.

Adolescent↗
PubMed1996

The effects of chronic industrial noise exposure on urinary cortisol, fatigue and irritability: a controlled field experiment.

This quasiexperimental field study explored the effect of noise attenuation on urinary cortisol excretion (sampled three times, at 6:30 and 10:30 AM and 1:30 PM) and reported fatigue and postwork irritability among 35 healthy industrial workers chronically exposed to high ambient noise levels (> 85 dB [A]) without using ear protectors. The results indicated that under conditions of chronic noise exposure the cortisol level at the end of the workshift was high and almost reached the morning level. This elevation in cortisol excretion was accompanied by high levels of accumulated fatigue and postwork irritability. Attenuating the noise reaching the eardrum by 30 to 33 dB, by fitting the same workers with earmuffs for a period of 7 working days, resulted in a significant improvement in both psychological and physiological stress reactions. Besides decreasing noise intensity, no other changes were made, either to ongoing work activities or to the other characteristics of the ambient noise. The cortisol level declined steadily during the workshift and exhibited the normal cortisol diurnal rhythm. At the end of the workshift, this level was significantly lower (P < .05) than that observed under the chronic noise-exposure condition. There was also a concomitant reduction in reported fatigue (P < .05) and postwork irritability (P < .01). These findings demonstrate the "net" contribution of ambient noise to elevating stress reactions to regular work demands.

Adult↗
PubMed1996

Glaucoma and visual outcome in central retinal vein occlusion.

Glaucoma is a recognized risk factor for central retinal vein occlusion. The authors retrospectively reviewed charts of fifty patients with central vein occlusion examined over a 5-year period. The visual outcome and clinical characteristics of eyes with and without glaucoma were compared. There were 32 eyes without glaucoma and 18 eyes with glaucoma. Final visual acuity of 20/100 or better was obtained in 22% of eyes with glaucoma, compared with 34% of eyes without glaucoma, and final visual acuity of finger counting and less was found in 56% and 22%, respectively (p = 0.02). The rate of ischemic occlusion was higher in the glaucoma group, 44% and 28% respectively, but the difference did not reach statistical significance. There was no difference in the rate of neovascular complications and macular edema between the two groups. The results suggest that glaucoma has an adverse effect on the visual outcome of eyes with central vein occlusion.

Aged↗
PubMed1996

Industrial accidents are related to relative body weight: the Israeli CORDIS study.

OBJECTIVES: The accident rate might be influenced by intrinsic characteristics of the workers, by risks inherent in the work environment, or a combination of these factors. As increased weight may be associated with sleep disturbances and fatigue, a high body mass index (BMI) might be an independent risk factor for accidents in industrial workers. METHODS: 3801 men were examined and followed up for two years for the occurrence of accidents. The objective environmental conditions were recorded and translated into a single score of ergonomic stress levels. Height and weight were recorded, as were possible confounding factors including measures of fatigue, type A personality, total night time sleep, job satisfaction, somatic complaints, smoking, and education levels. RESULTS: Both BMI and ergonomic stress levels independently predicted involvement in accidents (two or more) with those in the highest BMI quartile who worked in an environment with high ergonomic stress levels having a 4-6 times increased risk of accidents compared with those in the lowest BMI quartile who worked in an environment with low ergonomic stress levels (95% confidence interval (95% CI) 2.4-9.0, P < 0.001). Although increasing somatic complaints and a low educational level also were predictors of accidents, they did not mediate the effect of the BMI on the accident rate. Increasing age, less smoking, and decreased sleep hours were significantly associated with an increased BMI, but the association of BMI and involvement in accidents also could not be explained by those factors or the other confounders. CONCLUSIONS: BMI independently influences the accident rate. Further studies warranted to confirm these findings and to explore mechanisms supporting biological plausibility.

Accidents, Occupational↗
PubMed1996

Bilateral iridocorneal endothelial syndrome presented as Cogan-Reese and Chandler's syndrome.

PURPOSE: Iridocorneal endothelial (ICE) syndrome includes Chandler's syndrome, essential iris atrophy, and the Cogan Reese syndrome. The purpose of this article is to describe a rare case with two forms of the syndrome simultaneously. METHODS: A case of Cogan Reese syndrome in one eye and Chandler's syndrome in the fellow eye is reported. RESULTS: During 5 years of follow-up only slight progression, manifested in episodes of blurred vision, occurred because of corneal changes. Glaucoma did not develop. CONCLUSION: ICE syndrome is considered as unilateral, although cases of bilateral involvement of the same variant have been described. But a simultaneous presentation of two different forms might occur, as in this patient.

Adult↗
PubMed1995

Reduced ambulatory heart rate response to physical work and complaints of fatigue among hypertensive males treated with beta-blockers.

Treatment with beta-blockers affects oxygen metabolism and lipolysis during physical exertion. Together with possible central nervous system effects, this may impair the work capacity of treated hypertensive subjects. In a study of 1619 male employees, aged 45-64 years, mean resting and ambulatory heart rate (HR) and complaints of fatigue were compared between hypertensive workers treated with beta-blockers and untreated hypertensives and normotensives under low and high workload conditions. Treated hypertensives had lower mean resting HRs compared with normotensives and untreated hypertensives. Their change from resting to ambulatory HR during low and high workload was also lower than normotensives and untreated hypertensives, and they had higher fatigue scores than their untreated counterparts at both workload levels. The highest fatigue score was reported by treated subjects under high workload. These findings demonstrate a reduced HR response to physical work accompanied by more symptoms of fatigue during treatment with beta-blockers. When hypertensives are engaged in physically demanding work, other classes of antihypertensive therapy should be considered.

Adrenergic beta-Antagonists↗
PubMed1995

Repetitive work, work underload and coronary heart disease risk factors among blue-collar workers--the CORDIS study. Cardiovascular Occupational Risk Factors Determination in Israel.

Evidence from survey-based studies suggests that monotonous work increases the risk of coronary heart disease (CHD). In this study of 1944 male and 832 female blue-collar workers aged 20-64 yr, we examined the association of CHD risk factors with two distinct objective work conditions--repetitive work (3 levels) and work underload-compared to varied work. After controlling for shift work, high ambient noise exposure and four other possible confounders, repetitive work was positively associated with both blood pressure and serum lipid levels in women, and with blood pressure in men. However, elevated levels of these risk factors were obtained only for those in short-cycle (< 1 min) repetitive work. In women this was manifested in higher mean systolic (p = 0.003), diastolic (p = 0.01) blood pressure (BP), total cholesterol (p = 0.03) and serum glucose (p = 0.05) levels; and in men in higher systolic BP only (p = 0.002). Inconsistent results were obtained for those engaged in work underload. It was associated in men with higher mean systolic BP (p = 0.05) and in women with higher cholesterol (p = 0.05) and high density lipoprotein (p = 0.03) levels. These findings suggest that objective monotonous work conditions are more consistently related to CHD risk factors in women, especially those engaged in short-cycle (hectic) repetitive work.

Adult↗
PubMed1995

Objective and subjective work monotony: effects on job satisfaction, psychological distress, and absenteeism in blue-collar workers.

The relation of objective work conditions (work underload, repetitive or varied work) and subjective monotony to job satisfaction, psychological distress, and sickness absence was examined in 1,278 male and female workers. Subjective monotony was moderately related to the objective work conditions. Hierarchical regression analyses showed that the effects on all outcomes were partially mediated by subjective monotony and were also directly related to repetitive work and work underload. Job satisfaction and psychological distress were mainly related to subjective monotony, whereas sickness absence was equally related to the work conditions and subjective monotony. The highest impact was observed for short-cycle repetitive work. Testing sex interactions revealed that sickness absence was related to the work conditions in women but not in men. The findings highlight the significance of noting the actual work conditions in predicting employee outcomes.

Absenteeism↗
PubMed1994

Noise exposure, noise annoyance, use of hearing protection devices and distress among blue-collar workers.

OBJECTIVES: This study tested the hypotheses that, in high noise levels [> or = 85 dB(A)], hearing protection devices are used largely by workers sensitive to noise, as reflected by reports of noise annoyance, and that the usage would reduce distress symptoms. METHODS: Data collected from 1587 healthy male blue-collar workers included noise exposure level, noise annoyance, use of hearing protection devices, distress symptoms (somatic complaints and poststress irritability), and possible confounding by age, education and ethnic origin. RESULTS: Multiple logistic regression results indicated that the use of hearing protection devices was related to noise exposure level [odds ratio (OR) 2.94, 95% confidence interval (95% CI) 2.58--3.30], but more so to high noise annoyance (OR 3.03, 95% CI 2.77--3.29), even after control for age, education, and ethnic origin. No interaction was found between noise level and noise annoyance. These findings highlight the contribution of noise annoyance to the use of hearing protection devices. Of the 42.6% of workers using hearing protection devices in the presence of high ambient noise, 60% were highly annoyed. Noise-annoyed workers also tended to wear hearing protection devices even in low noise levels. The use of hearing protection devices was associated with lower distress symptoms among the low and moderately annoyed workers, but among the highly annoyed workers the reverse was true. CONCLUSIONS: Thus, for the highly annoyed workers, the use of hearing protection devices was perhaps an additional source of stress. One immediate implication of this study is that future intervention procedures should focus on unannoyed workers who tend to use hearing protection devices less.

Adult↗
PubMed1994

Nonpeptidic analogues of the Arg-Gly-Asp (RGD) sequence specifically inhibit the adhesion of human tenon's capsule fibroblasts to fibronectin.

PURPOSE: Scar formation from the process of wound healing is mediated primarily by fibroblasts and is a major problem in ophthalmology in general and in glaucoma therapy in particular. Interactions between fibroblasts and glycoprotein components of the extracellular matrix (ECM) are among the major causes of scar formation. Recognition of ECM glycoproteins occurs via cell surface integrins that are specific for adhesion epitopes, such as the Arg-Gly-Asp (RGD-) containing amino acid sequence. The RGD sequence, which is present in several matrix and plasma proteins, including fibronectin (FN) and vitronectin, is involved in cell-ECM interactions that occur during inflammatory and homeostatic reactions. The present study was designed to examine the possibility of using RGD-mimetics as inhibitors of fibroblasts-FN interactions. METHODS: Two nonpeptidic mimetics of RGD were designed and constructed, and their inhibitory effect on the adhesion of human tenon's capsule fibroblasts to FN was examined. SF-6,5 consisting of the carboxylate group of Asp and the guanidinium group of Arg divided by a linear atom spacer and a newly designed mimetic, designated NS-11, were examined herein. RESULTS: The RGD mimetics, SF-6,5 and NS-11, but not an Arg-Gly-Glu (RGE) mimetic inhibited the adhesion of ocular fibroblasts to immobilized FN. SF-6,5 and NS-11 did not inhibit adhesion of the fibroblasts to laminin or spontaneous proliferation of fibroblasts. Trypsin pretreatment of the nonpeptidic RGD mimetics did not affect their ability to inhibit adhesion of the ocular fibroblasts to FN, whereas that of the RGD-containing peptide was abolished by the pretreatment. CONCLUSION: Nonpeptidic mimetics of RGD are attractive candidates for therapeutic agents to prevent the formation of scar tissue and related RGD-dependent pathologic events.

Antibodies, Monoclonal↗
PubMed1993

Optic nerve compression by carotid arteries in low-tension glaucoma.

Low-tension glaucoma (LTG) is manifested by glaucomatous optic nerve damage and visual field loss despite normal intraocular pressure (IOP). We describe 62 patients with classical signs of LTG. Computed tomography (CT) was performed in all patients. In 56 of the patients (90.3%), pathology of the intracavernous carotid arteries adjacent to the intracranial opening of the optic canal could be demonstrated. In 28 patients (45.2%) a clear asymmetry of the optic nerve cupping was found and could be correlated with the severity of the carotid artery pathology. A control group of 24 age-matched patients included five (20.8%) with intracavernous carotid artery calcification and only one (4.2%) with intracavernous ectasia. We suggest that calcification, dilatation and ectasia of the carotid artery into the optic canal may play an important role in the pathogenesis of many cases of LTG. The close proximity of the carotid artery to the optic nerve at this location may result in compressive neuropathy with subsequent glaucomatous damage of the optic nerve head.

Aged↗