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31.
Nermin Zawilla Dalia Shaker Amaal Abdelaal Wael Aref 《International journal of occupational and environmental health》2014,20(3):194-206
Background:
The gene–environment interaction in the pathogenesis of hypertension has not been extensively studied in occupational noise.Objectives:
The aim of this study was to determine the relationship between noise and hypertension in Egyptian workers, the interaction of angiotensin-converting enzyme (ACE) gene polymorphisms as modifiers, and the possible relationship between noise hearing impairment and hypertension.Methods:
Study subjects were divided into two groups depending on noise exposure level. The control group (n = 161) was exposed to noise intensity <85 dB and the exposed group (n = 217) was exposed to noise intensity ≧85 dB. A polymerase chain reaction was used to differentiate the various genotypes of ACE insertion/deletion (I/D) and ACE G2350A.Results:
Noise significantly increased the likelihood of hypertension. Carriers of the genotypes AG, GG, and DD were vulnerable to hypertension on noise exposure. No association between hypertension and hearing impairment or noise-induced hearing loss (NIHL) was found.Conclusion:
Our results support the association between ACE gene polymorphisms and occurrence of hypertension in noise-exposed workers. 相似文献32.
33.
34.
S I Hassan S S Botros H M el-Nahal M E Azab Z A Shaker A A el-Garem 《International journal of immunopharmacology》1990,12(2):207-215
Mice infected for 45 days with 120 Schistosoma mansoni cercariae and treated with praziquantel in a dose of 500 mg/kg for two consecutive days had a significant lower resistance to reinfection when challenged two weeks after treatment (45% compared to 88% in infected challenged untreated mice). In praziquantel-treated mice, the reduction in the per cent resistance was accompanied by a diminution in the size of hepatic granulomata and its in vivo correlate the delayed foot pad swelling. Moreover, the granuloma proportionate T-cell subset enumeration revealed a significant reduction in the number of T-helper cells. The humoral immune response as measured by the immediate foot pad swelling was not affected by praziquantel. Results reveal besides the diminution of the state in resistance to reinfection after praziquantel, possible involvement of egg-related pathology as a T-cell mediated reaction and as a mechanical obstacle in maintenance of this resistance. 相似文献
35.
Z A Shaker H I Hassanein R R Hamed S S Botros F S Mahmoud S H Mohamed A A el Garem N de Jonge A M Deelder 《International journal of immunopharmacology》1992,14(2):151-158
In two groups of mice infected with 60 (group I) and 120 (group II) Schistosoma mansoni cercariae, respectively, the effects of intensity and duration of infection, and of praziquantel therapy (curative vs subcurative dose) on the levels of circulating anodic antigen (CAA), were studied. CAA was measured in trichloracetic acid-treated serum samples with an avidin-biotin enzyme-linked immunosorbent assay (AB-ELISA) using the monoclonal anti-CAA antibody. Total worm burdens, oogram patterns and ova counts/g liver and intestine were followed up. The lowest detectable level of CAA was about 1.0 ng/ml, and was positive with a worm load of 3-5/mouse. CAA levels became already detectable as early as 1-2 weeks post-infection (pi) before any parasitological parameter and showed a significant drop from the 11th-12th week pi onwards. A positive correlation was demonstrated between the CAA level and worm load. Following successful praziquantel therapy, CAA disappeared earlier than any of the other parameters studied. 相似文献
36.
Angela Keniston Matthew Sakumoto Gopi J. Astik Andrew Auerbach Shaker M. Eid Kirsten N. Kangelaris Shradha A. Kulkarni Tiffany Lee Luci K. Leykum Anne S. Linker Devin T. Worster Marisha Burden 《Journal of general internal medicine》2022,37(15):3956
BackgroundDuring the initial wave of COVID-19 hospitalizations, care delivery and workforce adaptations were rapidly implemented. In response to subsequent surges of patients, institutions have deployed, modified, and/or discontinued their workforce plans.ObjectiveUsing rapid qualitative methods, we sought to explore hospitalists’ experiences with workforce deployment, types of clinicians deployed, and challenges encountered with subsequent iterations of surge planning during the COVID-19 pandemic across a collaborative of hospital medicine groups.ApproachUsing rapid qualitative methods, focus groups were conducted in partnership with the Hospital Medicine Reengineering Network (HOMERuN). We interviewed physicians, advanced practice providers (APP), and physician researchers about (1) ongoing adaptations to the workforce as a result of the COVID-19 pandemic, (2) current struggles with workforce planning, and (3) evolution of workforce planning.Key ResultsWe conducted five focus groups with 33 individuals from 24 institutions, representing 52% of HOMERuN sites. A variety of adaptations was described by participants, some common across institutions and others specific to the institution’s location and context. Adaptations implemented shifted from the first waves of COVID patients to subsequent waves. Three global themes also emerged: (1) adaptability and comfort with dynamic change, (2) the importance of the unique hospitalist skillset for effective surge planning and redeployment, and (3) the lack of universal solutions.ConclusionsHospital workforce adaptations to the COVID pandemic continued to evolve. While few approaches were universally effective in managing surges of patients, and successful adaptations were highly context dependent, the ability to navigate a complex system, adaptability, and comfort in a chaotic, dynamic environment were themes considered most critical to successful surge management. However, resource constraints and sustained high workload levels raised issues of burnout.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11606-022-07480-x.KEY WORDS: COVID-19, hospital medicine, workforce planning, surge planning, focus groups, qualitative 相似文献
37.
Nutritional supplements or complementary and alternative medicines (CAM) are currently being investigated for their use in preventing, inhibiting, and reversing the progression of cancer. Natural agents and their derivatives such as vitamin A, selenium, green tea, resveratrol, aspirin, and probiotics have potential benefits in chemoprevention. There is also growing evidence for the use of natural products as adjunctive therapy alongside conventional cancer treatments. Nutritional supplements expenditures demonstrated greater growth than pharmaceuticals, with approximately 80% of cancer patients using natural products. Current issues with nutritional supplements use in cancer treatment include insufficient or conflicting evidence, poor quality control, potential interactions with chemotherapy, and potential efficacy in relation to changes in certain biomarkers, but long-term implications remain largely unresolved. Continued research is needed to lend credibility to these potentially valuable naturally driven supplements in the prevention and potentially in the treatment of cancer in conjunction with standard pharmaceuticals. 相似文献
38.
Mousa SA Abulencia JP McCarty OJ Turner NA Konstantopoulos K 《Journal of cardiovascular pharmacology》2002,39(4):552-560
This study was undertaken to compare the platelet binding characteristics and anti-platelet efficacy of a nonpeptide glycoprotein IIb/IIIa antagonist roxifiban with orbofiban in static and dynamic adhesion and aggregation assays. The results indicate that roxifiban binds with higher affinity to glycoprotein IIb/IIIa receptors and exhibits slower dissociation rates than orbofiban. Furthermore, the platelet inhibitory effects of roxifiban, but not orbofiban, were unaffected by changes in plasma calcium concentrations. Both agents reduced, in a concentration-dependent manner, the size of platelet thrombi deposited onto collagen I upon perfusion of heparinized blood at a shear rate of 1,500/s. At a clinically achievable concentration of 60 nM, roxifiban abrogated the formation of thrombi containing > 20 platelets per thrombus, thereby displaying comparable in vitro efficacy to that achieved by the theoretical maximal abciximab blood concentration (3.5 microg/ml) produced after standard treatment. In contrast, orbofiban, even at 500 nM, was only effective in inhibiting the formation of larger platelet thrombi (> or =150 platelets per thrombus). Pretreatment of surface-anchored platelets with roxifiban (100 nM), but not orbofiban (500 nM), inhibited monocytic THP-1 cell attachment under flow. However, this heterotypic adhesion process was also suppressed when orbofiban (500 nM) was maintained in the perfusion buffer during the entire course of flow experiment. These findings demonstrate roxifiban (unlike orbofiban) is a potent glycoprotein IIb/IIIa antagonist with a long receptor-bound lifetime and prolonged anti-platelet efficacy and may thus be beneficial for the treatment and prevention of acute ischemic syndromes. 相似文献
39.
PURPOSE: A previous study has demonstrated that the longitudinal muscle possesses electric activity, while the circular does not (A. Shafik and A. A. Shafik, 2000, Front. Biosci. 5, b5). In the current study, we investigated the mechanism of action of the two colonic muscle coats in the motility of the gut. METHODS: Fourteen patients (43.8 years, 10 men) with left colon or rectal cancer were scheduled to have transverse colostomy as a part of their operation. The electric activity of the ascending colon was recorded by three electrodes applied to each of the circular and the longitudinal (taenia coli) muscle coats. Simultaneously, the colonic pressure was recorded before and after colonic distension. The test was repeated after longitudinal muscle anesthetization. RESULTS: Electric waves in the form of pacesetter (PPs) and action (APs) potentials were recorded from the longitudinal but not the circular muscle fibers. APs were associated with an intracolonic pressure rise. Colonic distension produced significant increase in the PPs and APs recorded from the longitudinal muscle with appearance of similar electric activity from the circular muscle. Electric activity and colonic pressure increased upon increase in the colonic distension until the balloon in the proximal part of the ascending colon moved to the transverse colon in one mass contraction. Ten minutes after longitudinal muscle anesthetization, no electric activity was recorded from the longitudinal and circular muscles upon colonic distension. CONCLUSIONS: The electric waves appear to be transmitted from the longitudinal to the circular muscle upon colonic distension. The giant migrating contractions of the colon that move the food bolus from the cecum to the transverse colon are suggested to be a function of the longitudinal muscle electric activation with gut lumen modulation by the circular fibers. 相似文献
40.
Trigui W Le Pimpec-Barthes F Shaker W Lang-Lazdunski L Riquet M 《The Annals of thoracic surgery》2002,74(3):923-924
The simultaneous occurrence of bronchopleural fistula (BPF) and esophagopleural fistula (EPF) after pneumonectomy is very rare. We describe a 60-year-old man who developed empyema associated with bronchopleural fistula as a complication of a right pneumonectomy. Initial chest tube drainage and antibiotic therapy were ineffective. Five months later ingested food particles appeared in the drainage fluid. Esophagoscopy revealed an esophageal fistula of 10 mm in diameter. After nutritional support by feeding jejunostomy both BPF and EPF were repaired by subscapular muscle myoplasty and extensive thoracoplasty through a right thoracotomy. Endoscopic examination performed 1 month after surgery showed complete closure of both fistulas and 9 months after surgery the patient was eating and gaining weight. The patient's death was due to aspiration pneumonia of another origin. 相似文献