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51.
Background: It was aimed to evaluate the preventive efficacy of trimetazidine in an experimental chronic pancreatitis rat model.Methods: Chronic pancreatitis model was accomplished with caerulein and alcohol administration. In the study, 40 female Sprague Dawley rats were randomized into 5 groups containing 8 animals in each. Group 1 (chronic pancreatitis); group 2 (chronic pancreatitis + low-dose trimetazidine group); group 3 (chronic pancreatitis + high-dose trimetazidine group); group 4 (placebo group (chronic pancreatitis + saline)); group 5 (sham group). 24 hours after the last injection, all animals were sacrificed. Tumor necrosis factor-alpha, transforming growth factor-β, malondialdehyde, and glutathione peroxidase levels were tested in blood samples. Histopathologic examinations were conducted by a senior pathologist who was unaware of the group allocations.Results: Results of biochemical parameters of the trimetazidine groups (groups 2 and 3) were significantly favorable compared with the chronic pancreatitis group (group 1) (P < .05). The difference between the low-dose- and the high-dose trimetazidine group (group 3) was significant in terms of blood tests (P < .05). The difference between the low-dose trimetazidine group and the chronic pancreatitis group was not significant in terms of histopathologic scores (P > .05); however, the difference was significant between the high-dose trimetazidine group and the chronic pancreatitis group (P < .05).Conclusions: To the best of our knowledge, this current research is the first study that evaluates trimetazidine’s efficacy in the chronic pancreatitis rat model. Trimetazidine has affirmative preventive properties in the chronic pancreatitis course.  相似文献   
52.
With the increase in the importance of using green energy sources to meet the world''s energy demands, attempts have been made to push perovskite solar cell technology toward industrialization all around the world. Improving the properties of perovskite materials as the heart of PSCs is one of the methods to fabricate favorable photovoltaic (PV) solar cells based on perovskites. Here, cadmium chloride (CdCl2) was used as an additive source for the perovskite precursor to improve its PV properties. Results indicated CdCl2 improves the perovskite growth and tailors its crystalline properties, suggesting boosted charge transport processes in the bulk and interfaces of the perovskite layer with electron–hole transport layers. Overall, by incorporation of 1.0% into the MAPbI3 layer, a maximum power conversion efficiency of 15.28% was recorded for perovskite-based solar cells, higher than the 12.17% for the control devices. The developed method not only improved the PV performance of devices but also boosted the stability behavior of solar cells due to the passivated domain boundaries and enhanced hydrophobicity in the CdCl2-based devices.

With the increase in the importance of using green energy sources to meet the world''s energy demands, attempts have been made to push perovskite solar cell technology toward industrialization all around the world.  相似文献   
53.
Introduction: In etiology of Alzheimer’s disease (AD), involvement of amyloid β (Aβ) plaque accumulation and oxidative stress in the brain have important roles. Several nanoparticles such as titanium dioxide, silica dioxide, silver and zinc oxide have been experimentally using for treatment of neurological disease. In the last decade, there has been a great interest on combination of antioxidant bioactive compounds such as selenium (Se) and flavonoids with the oxidant nanoparticles in AD. We evaluated the most current data available on the physiological effects of oxidant and antioxidant nanoparticles.

Areas covered: Oxidative nanoparticles decreased the activities of reactive oxygen species (ROS) scavenging enzymes such as glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase in the brain of rats and mice. However, Se-rich nanoparticles in small size (5–15 nm) depleted Aβ formation through decreasing ROS production. Reports on low levels of Se in blood and tissue samples and the low activities of GSH-Px, catalase and SOD enzymes in AD patients and animal models support the proposed crucial role of oxidative stress in the pathogenesis of AD.

Expert commentary: In conclusion, present literature suggests that Se-rich nanoparticles appeared to be a potential therapeutic compound for the treatment of AD.  相似文献   
54.
The goal of this investigation was to study the protective effects of thymoquinone (TQ) and methotrexate (MTX) on collagen-induced arthritis (CIA) in rats. On day 0 under ether anesthesia, the experimental groups were immunized with 0.5 mg native chick collagen II (CII) solubilized in 0.1 M acetic acid and emulsified in Freund's incomplete adjuvant. Control rats were gavaged with vehicle, whereas CII was administered intradermally. In addition, arthritis treated with TQ group received TQ (10 mg kg(-1) bw by gavage once a week for 3 weeks starting on day 0); and arthritis treated with MTX group received MTX (MTX was suspended in corn oil and administered by gavage at 1 mg kg (-1) bw once a week for 3 weeks starting on day 0). A significant decrease in the incidence and severity of arthritis by clinical and radiographic assessments was found in recipients of therapy, compared with that of controls. The MTX treatment significantly (P<0.01) decreased the elevated serum NO, urea and creatinine in arthritic rats. Likewise, TQ treatment was also able to reduce significantly (P<0.05) serum NO, urea and creatinine levels, but to lesser extent than MTX. The histopathologic abnormalities are consistent with the hydropic epithelial cell degenerations and moderate tubular dilatation in the some proximal and distal tubules. The severity of the degenerative changes in most of the shrunken glomerules and vascular congestion were also observed in arthritic animals. Preventive treatment of TQ and especially MTX significantly inhibited kidney dysfunction and this histopathologic alterations. These studies indicate that TQ can be used similar to MTX as a safe and effective therapy for CIA and may be useful in the treatment of rheumatoid arthritis.  相似文献   
55.
Purpose : To evaluate the additive ocular hypotensive effect of latanoprost and dorzolamide in combination, on intraocular pressure reduction in patients with elevated intraocular pressure (IOP). Methods : Thirty patients with ocular hypertension or early capsular or primary open-angle glaucoma and elevated IOP were randomly assigned to two parallel treatment groups. The treatment period was twenty days. Fifteen patients (Group 1) received latanoprost once daily during the first ten days and, in addition, dorzolamide three times daily during the second ten days. Fifteen patients (Group 2) received dorzolamide three times daily during the first ten days and, in addition latanoprost, once daily during the second ten days. IOP was measured and conjunctival hyperemia was evaluated. Results : In Group 1, the mean IOP on day 0 was 26.8 mmHg; on day 10, 18.7 mmHg; and on day 20, 15.9 mmHg. In Group 2, the mean IOP on day 0 was 26.3 mmHg; on day 10, 21.2 mmHg; and on day 20, 16.1 mmHg. Both groups had clinically significant IOP- lowering effect on day 10 as compared with baseline day (30.2% and 19.4% respectively) (p < 0.01). When dorzolamide was added to latanoprost, the additional IOP reduction was 2.8 mmHg (15%) (p<0.01) compared with 5.1 mmHg (24.1%) (p<0.01when latanoprost was added to dorzolamide. No local serious adverse reactions were observed. A mild but statistically significant increase in conjunctival hyperemia was seen in latanoprost applied patients. Conclusions : The results showed that latanoprost and dorzolamide can be combined successfully to reduce IOP with their additive effects.  相似文献   
56.
BACKGROUND AND OBJECTIVE: To evaluate patient-reported pain induced by phacoemulsification performed by residents using topical anesthesia. PATIENTS AND METHODS: This prospective study comprised 81 eyes of 76 consecutive patients having phacoemulsification under topical anesthesia. Surgery was performed by an experienced surgeon (group 1; n=41 eyes) or by two residents (group 2; n=40 eyes). No sedation or intracameral anesthesia was used in either group. Eighty eyes had clear corneal phacoemulsification with foldable acrylic posterior chamber intraocular lens implantation. Patients were asked postoperatively to grade the pain they experienced during the procedure using a visual analog pain scale from 0 to 10. RESULTS: The median pain score for the overall pain was 1.59 +/- 1.43 (range: 0 to 6) in group 1 and 1.95 +/- 1.64 (range: 0 to 7) in group 2 (P = .291). The mean pain score for the maximum pain perceived was 2.39 +/- 1.86 (range: 0 to 7) in group 1 and 2.53 +/- 1.67 (range: 0 to 7) in group 2 (P = .734). There was no significant correlation between the duration of surgery and the overall pain score (r = 0.102, P = .365). CONCLUSION: Topical anesthesia had sufficient analgesic effects in selected patients undergoing phacoemulsification cataract surgery by resident surgeons. The pain felt during the operation was low and tolerable.  相似文献   
57.
Mulibrey nanism is a rare autosomal-recessive disorder characterized by prenatal onset severe growth retardation and pericardial constriction associated with abnormalities of muscle, liver, brain and eye. More than 80% of previously reported patients are of Finnish origin in whom a founder mutation in the TRIM37 gene have been described. We report on a 7-year-old Turkish boy who presented with classical phenotypic features of mulibrey nanism. Mutation screening of the TRIM37 gene revealed that the proband had a homozygous two base pair deletion, c.1894_1895delGA, resulting in a frame-shift and a premature termination codon. Our proband is one of the rare examples of mulibrey nanism outside Finland and extends the mutation spectrum in this disorder.  相似文献   
58.
AIM: Recent findings show that the vaginal mucosa can develop an allergic response to environmental allergens and there is a strong association between atopy and some recurrent vulvovaginal infections. In this study, we investigated prospectively the rate of atopy in patients with recurrent vulvovaginitis of undetermined etiology (RVV). MATERIAL AND METHODS: After being investigated by a gynecologist, 35 patients with RVV who were considered as undetermined etiology formed the study group. The control group consisted of 150 healthy females. Study and control groups were investigated for atopy by means of skin prick test for common aeroallergens. Associated allergic disease and familial atopy history of the subjects were recorded. RESULTS: The rate of atopy (11/35; 31.4% vs 9/150; 6%) was significantly higher (P < 0.001) in the study group than in the controls. Familial history of atopy was significantly more frequent in the study group than in the controls (10/35; 28.6% vs 8/150; 5.3%, P < 0.05). RVV in atopics is more associated with seasonal rhinitis than in nonatopics (5/11; 45.4% vs 2/24; 8.3%, P < 0.05). CONCLUSION: We concluded that a significant number of RVV is associated with atopy. Although the exact mechanism(s) of this relationship remains to be investigated atopy might be a causative and/or contributing factor in the pathogenesis of RVV.  相似文献   
59.
Older individuals are more vulnerable to severe coronavirus disease 2019 and medical complications. Vaccination stands as an efficient and safe vanguard against infection. However, negative attitudes and perceptions pertaining to available vaccines might hinder community inoculation. The aim of this study was to assess vaccine hesitancy and its psychosocial determinants among the elderly in Qatar.We conducted a cross-sectional study between October 15 and November 15, 2020, using a composite online survey including the Vaccine Attitudes Examination Scale in addition to questions on sociodemographic correlates and the role of healthcare professionals.The vaccine hesitancy rate was 19.5%. The main reasons for willingness to vaccinate included understanding the nature of disease and role of vaccination, in addition to information provided by physicians. Fears mainly centered around vaccine safety. Vaccine hesitators were more likely to be non-Qatari and having received the influenza vaccine at least once. Gender, marital status, socioeconomic status, educational level, and having completed childhood vaccinations were not associated with vaccine hesitancy.Efforts should be directed toward raising awareness of vaccine efficacy and safety profiles. Physicians should additionally be educated about their pivotal role in advocating vaccine acceptance. We recommend reassessing vaccine hesitancy and its associated factors following a year of campaigning and vaccine administration to identify and target vulnerable groups.  相似文献   
60.
In potassium-depolarized guinea-pig left atria treated with isoproterenol, calcium entry blocking activities of adenosine and its potentiating compounds, dipyridamole, lidoflazine and dilazep were studied and compared to verapamil and diltiazem. pA2 values for various drugs were calculated using concentration-response curves for calcium (parallel shift to the right). The order of potency for the calcium entry blocking effect was: verapamil greater than diltiazem greater than adenosine greater than lidoflazine = dilazep greater than dipyridamole. Adenosine caused negative inotropic effects in depolarized left atria. The negative inotropic effect of adenosine was very quick in onset and was potentiated by erythro-6-amino-9(2-hydroxy-3-nonyl)-purine hydrochloride (EHNA), an adenosine deaminase inhibitor, suggesting that adenosine was being degraded. The effect of adenosine was quickly abolished by adenosine deaminase (ADA) and antagonized by 8-phenyltheophylline (8-PT), suggesting that the action of adenosine was most likely through the surface membrane receptor sites. The negative inotropic effects of dilazep and dipyridamole were only partially reversed by ADA and 8-PT, while that of lidoflazine was not affected by these agents. These findings suggest that the mechanism(s) of negative intotropic effect of lidoflazine was different from that of dilazep and dipyridamole. These data suggest that the negative intropic effect of dilazep is most likely due to a direct calcium entry blocking effect and in part due to its adenosine potentiating effect. However, the calcium entry blocking effect of lidoflazine is independent of adenosine.  相似文献   
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