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51.
The low dose of radiation (LDR) has received growing attention for its beneficial neuroprotective effect. This study was designed to investigate the enhancing effect of LDR on the antidepressant potential of resveratrol against diazepam‐induced depression in mice. Female mice divided into five groups; control, diazepam (2 mg/kg), LDR (0.5Gy) + diazepam, resveratrol (20 mg/kg) + diazepam, LDR + resveratrol+diazepam. Mice received diazepam showed depressive symptoms as evidenced by decreased locomotor activity in the open field and increased immobility time in the forced swimming and tail suspension tests integrated with a marked decline in biogenic amines (serotonin, norepinephrine, and dopamine) in brain tissues. These effects were ameliorated by LDR or resveratrol administration demonstrating an antidepressant activity. Interestingly, LDR triggered the antidepressant effect of resveratrol as it restored the changes in behavioral tests, neurotransmitters, and neuro‐histoarchitecture. In conclusion, these findings suggested that LDR could be considered as a novel adjuvant that augmented the resveratrol antidepressant effect and might serve as a potential therapeutic approach for depression.  相似文献   
52.
53.

Purpose

To measure the prevalence and degree of burnout among nursing staff working in Beni-Suef University Hospital.

Methods

A cross-sectional study was conducted from June–December 2016 on a group of nurses (n = 286) with a response rate of 79.4% (227/286). The Maslach Burnout Inventory-Human Service Survey tool was used to estimate the prevalence and degree of burnout.

Results

The mean age in the current study was 28.9 ± 7.8 years and the mean number of years of experience was 9.5 ± 7.7. Of the nurses, 43.2% were classified as having a moderate level of burnout and 32.6% as having a high level of burnout; 54.6% of nurses had average levels of emotional exhaustion, 48% scored high on depersonalization, and 77.5% had high levels of reduced personal accomplishment. The number of shifts, type of violence, shift timing, and quality of life perception proved to be significant predictors for high grades of burnout among nurses.

Conclusion

Burnout appeared to be common among participating nurses. Searching for and eliminating sources of stress in hospitals, in addition to teaching nurses coping strategies to deal with stress at work, seem to be important steps.
  相似文献   
54.
New 2-mercapto-quinazolin-4-one analogs were synthesized and tested for their in vitro anticancer activity, dihydrofolate reductase (DHFR) inhibition, and epidermal growth factor tyrosine kinase (EGFR-TK) inhibition activities. Compound 24 , which is characterized by a 2-benzyl-thio function, showed broad-spectrum anticancer activity with high safety profile and selectivity index. The concentrations of 24 causing 50% growth inhibition (GI50) and total cell growth inhibition (TGI) and its lethal concentration 50 (LC50) were 15.1, 52.5, and 91.2 µM, respectively, using 5-fluorouracil as a positive control. Also, it showed EGFR-TK inhibitory activity with IC50 = 13.40 nM compared to gefitinib (IC50 = 18.14 nM) and DHFR inhibitory potency with 0.30 μM compared to methotrexate (MTX; IC50 = 0.08 μM). In addition, compound 24 caused cell cycle arrest and apoptosis on COLO-205 colon cancer cells. Compounds 37, 21 , and 54 showed remarkable DHFR inhibitory activity with IC50 values of 0.03, 0.08, and 0.08 μM, respectively. The inhibitory properties of these compounds are due to an electron-withdrawing group on the quinazolinone ring, except for compound 54 . In a molecular modeling study, compound 24 showed the same binding mode as gefitinib as it interacted with the amino acid Lys745 via π–π interaction. Compound 37 showed a similar binding mode as MTX through the binding interaction with Lys68, Asn64 via hydrogen bond acceptor, and Phe31 via arene–arene interaction. The obtained model and substitution pattern could be used for further development.  相似文献   
55.
A new and simple HPLC assay method was developed and validated for the determination of etamsylate in human plasma. After protein precipitation with 6% perchloric acid, satisfactory separation was achieved on a HyPURITY C18 column (250 mm × 4.6 mm, 5 μm) using a mobile phase comprising 20 mM sodium dihydrogen phosphate-2 hydrate (pH was adjusted to 3.5 by phosphoric acid) and acetonitrile at a ratio of 95:5 v/v. The elution was isocratic at ambient temperature with a flow rate of 0.75 ml/min. Allopurinol was used as internal standard. The calibration curve was linear over the range from 0.25 to 20 μg/ml (r2 = 0.999). The limit of quantification for etamsylate in plasma was 0.25 μg/ml. The within day coefficient of variance (%CV) ranged from 3.9% to 10.2%, whereas the between-day %CV ranged from 3.1% to 8.7%. The assay method has been successfully used to estimate the pharmacokinetics of etamsylate after oral administration of a 500 mg tablet under fasting conditions to 24 healthy Egyptian human male volunteers. Various pharmacokinetic parameters including AUC0–t, AUC0–∞, Cmax, Tmax, t1/2, MRT, Cl/F, and Vd/F were determined from plasma concentration–time profile of etamsylate.  相似文献   
56.
Improvement of water solubility, dissolution rate, oral bioavailability, and reduction of first pass metabolism of OL (OL), were the aims of this research. Co-amorphization of OL carboxylic acid dispersions at various molar ratios was carried out using rapid solvent evaporation. Characterization of the dispersions was performed using differential scanning calorimetry (DSC), Fourier transform infrared spectrometry (FTIR), X-ray diffractometry (XRD), and scanning electron microscopy (SEM). Dispersions with highest equilibrium solubility were formulated as fast dissolving oral films. Modeling and optimization of film formation were undertaken using artificial neural networks (ANNs). The results indicated co-amorphization of OL-ascorbic acid through H-bonding. The co-amorphous dispersions at 1:2 molar ratio showed more than 600-fold increase in solubility of OL. The model optimized fast dissolving film prepared from the dispersion was physically and chemically stable, demonstrated short disintegration time (8.5?s), fast dissolution (97% in 10?min) and optimum tensile strength (4.9 N/cm2). The results of in vivo data indicated high bioavailability (144?ng h/mL) and maximum plasma concentration (14.2?ng/mL) compared with the marketed references. Therefore, the optimized co-amorphous OL-ascorbic acid fast dissolving film could be a valuable solution for enhancing the physicochemical and pharmacokinetic properties of OL.  相似文献   
57.

Background and purpose

Non-steroidal anti-inflammatory drugs are associated with several side effects, such as gastrointestinal mucosal damage, renal toxicity, and cardiovascular side effects. Aiming to find a novel analgesic/anti-inflammatory drug with minimal side effects, the present study was designed to screen and evaluate some newly synthesized pyrazole derivatives.

Method

Anti-inflammatory activity using carrageenan-induced rat paw edema and cotton-pellet-induced granuloma, COX-1/COX-2 selectivity using thin layer chromatography, and analgesic using hot plate and tail flick tests as well as ulcerogenic and renal side effects of the ten compounds were assessed.

Results and discussion

The results of the carrageenan-induced rat paw edema showed that the carboxyphenylhydrazone derivative (N9) was more potent than the chlorophenyl counterpart (N8) with a relative activity compared to celecoxib of 1.08 and ?0.13, respectively, after 1 h. Even though this is true, N9 caused significant increase in the ulcer index, creatinine, and Blood Urea Nitrogen levels. The cotton granuloma test showed that the carboxyphenylhydrazone derivative (N7) was also more potent than its chlorophenyl counterpart (N6) with a relative activity compared to celecoxib of 1.13 and 0.86, respectively. Moreover, adding an acetyl not only increased the anti-inflammatory activity from a relative activity compared to celecoxib of 0.57–1.17 for the compounds X4 and N5, respectively, in the granuloma test, but also increased the selectivity toward COX-2 from 0.197 to 47.979.

Conclusion

As a conclusion, from the ten compounds analyzed, N5 and N7 showed promising results as anti-inflammatory/analgesic agents with low ulcerogenicity and nephrotoxicity and thus should be further analyzed to determine the ED50 and other side effects.
  相似文献   
58.

Background

Patients diagnosed with type 1 diabetes mellitus (T1DM) face major daily challenges. Self-rated health (SRH) is a global measure of an individual's health related quality of life (HRQoL) and is based on the question, "In general, how would you rate your health?" Subjects rate their health as excellent, very good, good, poor or very poor. Our objective was to determine the HRQoL using the SRH measure and determine factors influencing responses. We hypothesized that better SRH responses were associated with shorter diabetes duration, better compliance and better glycemic control.

Methods

The standardized SRH measure was the instrument used for health related quality of life assessment. Logistic regression analysis was used to examine the association between SRH responses and selected variables.

Results

124 subjects, 64 females (51.6%) and 60 males (48.4%) were included. Average age was 13.08 (±3.19) and average diabetes duration was 5.82 (±1.60), while the mean HbA1C was 8.02 (±1.60). The majority rated their health as good (31%), 29% rated it as excellent, 11% as very good, 14% as poor and 15% as very poor. Regression analysis showed that regular exercise was the only predictor that was independently and significantly associated with a "better" self-health rating, with an OR of 12.84, CI of 1.425-115.727 and a p value of 0.023.

Conclusion

Regular exercise among Egyptian children with T1DM is strongly associated with a "better" overall health related quality of life and should be repeatedly encouraged.
  相似文献   
59.
Vitamin D deficiency has emerged as a public health problem worldwide due to its important role in health and disease. The present work is intended to examine prevalence of vitamin D deficiency among pregnant Saudi women and related risk factors. A cross-sectional study was carried out at King Fahad Medical City in Riyadh, Saudi Arabia. Serum 25-hydroxy vitamin D (25(OH)D) was measured by enzyme-linked immunosorbent assay in 160 pregnant women during the first trimester of pregnancy. Socio-demographic, lifestyle and maternal characteristics were collected and vitamin D intake was assessed using a 24-h dietary recall. Weight and height were measured using standardized methods. Vitamin D deficiency (25(OH)D < 50 nmol/L) and insufficiency (25(OH)D = 50–74 nmol/L) were reported in 50% and 43.8% of the study sample, respectively. Median serum 25(OH)D concentration was 49.9 nmol/L. Adequate vitamin D intake (≥600 IU/day) was reported among only 8.1% of pregnant women. Age group, educational level, sun exposure frequency and daytime and daily practice of exercise were significantly associated with vitamin D status. Overall, vitamin D deficiency was common among pregnant Saudi women in Riyadh. Steps should be taken to address the current situation, including increased sunlight exposure, consumption of fatty fish, and vitamin D supplements.  相似文献   
60.
The aim of this study was to investigate the antioxidant effect of acetyl-L-carnitine (ALC) against gamma-irradiation-induced oxidative damage in liver and lung tissue after total body irradiation with a single dose of 6Gy. To achieve the ultimate goal of this study, 40 adult rats were randomly divided into 4 groups of 10 animals each. Group I was injected intraperitoneally with saline solution for 5 consecutive days and served as control group. Group II was irradiated with a single dose of 6Gy. Group III was daily injected with ALC (250 mg kg(-1), i.p.) for 5 consecutive days. Group IV received a daily i.p. injection of ALC (250 mg kg(-1), i.p.) for 5 consecutive days and 1h after the last dose, rats were irradiated with a single dose (6Gy).The animals were sacrified after 24h. Administration of ALC for 5 consecutive days resulted in a significant increase in the activities of both superoxide dismutase (SOD) and glutathione peroxidase (GSHPx) and the level of reduced glutathione (GSH), in lung and liver tissues which were reduced by radiation treatment. Also, ALC resulted in a significant decrease in total nitrate/nitrite (NO(x)) and malondialdehyde (MDA) levels in both lung and liver tissues and a significant decrease in triglycerides, low-density lipoprotein-cholesterol (LDL), high-density lipoprotein-cholesterol (HDL), total cholesterol, Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) levels and Gamma glutamyl transpeptidase (GGTP) compared to irradiated group. In conclusion, data obtained from this study indicate that ALC could increase the endogenous antioxidant defense mechanism in rat and there by protect the animals from radiation-induced organs toxicity.  相似文献   
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