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Ischemic stroke accounts for about 87% of all strokes, causing long-term disability in adults, and is the second leading cause of death worldwide. In search of new therapeutic modalities, the use of neuroprotective agents loaded in nanocarriers to be delivered by noninvasive means (i.e. via intranasal route) became a popular approach. In the current study, melatonin (MEL) was loaded in lipidic nanocapsules (LNCs) prepared using the phase inversion method, and characterized in terms of size, polydispersity, zeta potential, in vitro drug release, viscosity, storage stability, and ex vivo permeation across sheep nasal mucosa. Moreover, MEL-LNCs were tested for efficacy in cerebral ischemia/reperfusion (I/R/) injury model through histopathological assessment, and analysis of oxidative stress markers, pro-inflammatory cytokines, and apoptotic markers. Results showed that LNCs exhibited particle size ranging from 18.26 to 109.8 nm, negative zeta potential, good storage stability, spherical morphology, and a burst release followed by a sustained release pattern. LNCs exhibited 10.35 folds higher permeation of MEL than the drug solution across sheep nasal mucosa. Post-ischemic intranasal administration of MEL-LNCs revealed lowering of oxidative stress manifested by a decrease in malondialdehyde levels, and elevation of glutathione and superoxide dismutase levels, lowering of the inflammatory markers tumor necrosis factor-α, NO, myeloperoxidase, and significant inhibition of Caspase-3 activity as an apoptotic marker. Western blot analysis delineated a recovery of protein expression Nrf-2 and HO-1 with downregulation in the parent inflammatory markers nuclear factor kappa B p65, inducible nitric oxide synthase, Bax, and Cytochrome C expressions, and upregulation of B-cell lymphoma-2 Bcl-2, hence promoting neuronal survival. This was supported by histological evidence, revealing significant restoration of hippocampal neurons. In light of the above, it can be concluded that MEL-LNCs could be a promising delivery system for nose to brain delivery for treatment of cerebral ischemia.  相似文献   
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BackgroundAn aberrant expression of long non‐coding RNA PVT1 has been associated with apoptosis in various cancer types. We aimed to explore the PVT1 and four apoptosis‐related proteins (p53, Bcl2, and PD‐1/PD‐L1) signature in thyroid cancer (TC).MethodsThe PVT1 expression level was measured in 64 FFPE TC paired samples by real‐time quantitative PCR. Overall and stratified analyses by different clinicopathological features were done. The apoptotic proteins were evaluated by immunohistochemistry staining.ResultsOverall analysis showed significant PVT1upregulation in TC tissues (p < 0.001). Similarly, subgroup analysis by BRAF V600E mutation showed consistent results. Lower expression of p53 was associated with mortality (p = 0.001). Bcl2 overexpression was associated with greater tumor size (p = 0.005). At the same time, HCV‐positive cases were associated with repressed Bcl2 expression levels (54.3% in HCV‐negative vs. 6.9% in HCV‐positive cases, p = 0.011). PD‐1 expression was associated with lymph node metastasis (p = 0.004). Enhanced PD‐L1 expression in the tumor was associated with a higher tumor stage, lymphovascular invasion, and mortality risk. Kaplan–Meier curves for overall survival showed that low p53 and high PD‐L1 expressions were associated with lower survival time. The p53‐positive staining is associated with a 90% decreased mortality risk (HR = 0.10, 95%CI = 0.02–0.47, p = 0.001), while patients with high PD‐L1 were five times more likely to die (HR = 4.74, 95%CI = 1.2–18.7, p = 0.027).ConclusionOur results confirm the upregulation of PVT1 in TC. The apoptosis‐related proteins (p53, Bcl2, and PD‐1/PD‐L1) showed different prognostic utility in TC patients; in particular, low p53 and high PD‐L1 expressions associated with low survival times. Further large‐scale and mechanistic studies are warranted.  相似文献   
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目的:以人民卫生出版社出版的《药事管理学》6版教材为蓝本,以本科阶段教学效果提高为指标,探讨改进课堂教学的方法。方法:以"药品注册管理"一章教学内容为例,筛选、调整和优化教学方法。结果:教学过程中,按照教学内容特点选择适宜教学方法,确定"教学方法与内容相融合"的课堂教学模式,在完成教学大纲基础上,适当增加执业药师及药学时事相关内容。结论:根据现代学生获取知识途径,充分利用高新技术背景下"智慧教室"资源,采取传统与现代教学方法相结合的教学模式,使课堂理论教学相关内容在以教材内容为主的前提下与国家当前药事时事相关联,可以增加学生课堂学习兴趣、培养自主学习习惯,从而提高教师教学能力和教学质量,实现培养具备专业知识、技能和法律、道德素养的药学应用型综合人才的预期目标。  相似文献   
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Objectives

To evaluate the safety of using the stiff end of a coronary wire to perforate an atretic pulmonary valve (PV) in patients with pulmonary atresia with intact ventricular septum (PAIVS).

Background

Radiofrequency perforation is an accepted modality to perforate the PV in patients PAIVS. However, the high cost precludes its widespread use.

Patients and methods

This is a single-center experience that spanned from March 2013 to January 2016 and involved 13 neonates who were severely cyanotic with PAIVS and with ductal-dependent pulmonary circulation. The stiff end of a coronary wire was used to perforate the atretic PV anterogradely, followed by balloon pulmonary valvuloplasty.

Results

The mean age of patients was 3.9?±?2.7?days and their mean weight was 2.8?±?0.19?kg. The mean oxygen saturation was 77.1?±?3.2%. All had membranous pulmonary atresia, with patent infundibulum and tripartite right ventricle. The valve was successfully perforated in 11 out of 13 patients. Death occurred in two patients (15.4%) owing to heart failure and sepsis. Patent ductus arteriosus stenting was performed 2?days after the procedure in one patient because of cyanosis followed by one and half ventricle repair at of age 5?months. Two patients (15.4%) had one and a half ventricle repair at age of 5?months and 6?months owing to insufficient anterograde pulmonary flow. Two patients (15.4%) underwent second intervention with balloon dilatation of the valve. The remaining seven patients (53.8%) had no further intervention. Two cases (15.4%) had femoral artery thrombosis treated with streptokinase. The mean duration of follow-up was 13.17?±?7?months. There was significant improvement in the degree of tricuspid incompetence. There was a significant growth in the tricuspid valve annulus during the follow-up (the mean Z score increased from ?0.8?±?0.9 to 0.1?±?0.9) (p?=?0.003). There was also a significant increase in the tricuspid valve annulus/mitral valve annulus ratio as its mean increased from 0.73?±?0.10 to 0.86?±?0.11 during follow-up (p?<?0.001).

Conclusion

Perforation of the atretic PV in selected cases with membranous atresia and patent infundibulum using the stiff end of a coronary wire is an effective alternative to using radiofrequency perforation.  相似文献   
16.

Background

Systemic sclerosis (SSc) is an autoimmune connective tissue disease with vascular, fibrotic and immune changes of skin and some internal organs. Anti-heterogeneous nuclear ribonucleoproteins (anti-hnRNP) were found in SSc patients.

Aim of the work

To assess anti-hnRNP A1 and A2 autoantibodies in limited SSc patients and to find their relation to clinical and hand radiographic characteristics.

Patients and methods

26 limited SSc patients and 16 matched control were studied. Skin thickness was scored according to the modified Rodnan skin score method (mRss) and radiologic examination by plain X-ray of the hand and wrist was performed anti-hnRNP A1 and A2 were measured in patients and control.

Results

All patients were females with a mean age of 37.5 ± 11.24 years and mean disease duration of 7.84 ± 1.19 years. 96.2% of cases showed juxta-articular osteoporosis, 38.5% with marginal erosions, 73.1% with surface erosions, 42.3% with subchondral cyst, 42.3% with metacarpophalangeal subluxation, 11.5% with marginal sclerosis, 80.8% with resorption of distal phalanges, 38.5% with resorption of distal ulna and 34.6% with calcinosis. Anti-hnRNPA1 was positive in all the patients but the anti-hnRNPA2 was positive in 21 (80.8%). Anti-hnRNP A1 and A2 showed significant difference between patients and control (5.66 ± 4.18 ng/ml vs 2.88 ± 0.82; p < 0.01 and 1.82 ± 0.36 vs 0.73 ± 0.08; p < 0.02, respectively). There was no significant correlation between the markers with the mRss or radiographic changes.

Conclusion

Joint affection in SSc is more frequent than expected. Anti-hnRNP A1 and anti hnRNP A2 antigens may be useful markers for SSc patient although no significant relation was found with radiologic findings.  相似文献   
17.

Background and study aims

Hepatitis C virus (HCV) infection is a severe problem among patients on maintenance haemodialysis who are at particular risk for blood-borne infections because of prolonged vascular access and potential for exposure to contaminated equipment. Occult hepatitis C virus infection (OCI) is defined as the presence of HCV RNA in liver or peripheral blood mononuclear cells (PBMCs) in the absence of detectable HCV antibody or HCV RNA in the serum. In this study, we aimed to investigate the existence of occult hepatitis C virus infection in PBMCs of haemodialysis (HD) patients in one center. Moreover, we tried to link the condition to risk factors associated with HCV infection in those patients.

Patients and methods

We included 40 patients with renal diseases undergoing regular haemodialysis who were repeatedly anti-HCV negative. HCV RNA detection was tested by Quantitative Real time PCR in serum and PBMCs.

Results

The results of this study revealed that 23% of our haemodialysis patients have occult hepatitis C virus infection. There was a highly significant increase in ALT levels in patients with OCI versus the negative group. Also, there is a significant increase of history of blood transfusion in patients with occult HCV (p?=?0.03) while the duration of haemodialysis showed no statistical significant difference between both groups. The viral load of the occult hepatitis C virus infection subjects ranged from 581to 74,307 copies/ml.

Conclusion

These results highlight the potential risk of hepatitis C virus transmission from patients within haemodialysis units in Egypt. Isolation of patients on dialysis machines depending on the results of hepatitis serological markers is not enough. Testing for hepatitis C virus -RNA in peripheral blood mononuclear cells is more reliable in identifying patients with an OCI when a liver biopsy is not available.  相似文献   
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