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91.
BackgroundIn recent era, pH sensitive polymeric carriers that combines the materials engineering and medicine is gaining researcher’s attention as they maximizes drug concentration at site of absorption and reduces side effects for e.g. orally administered cetirizine HCl (CTZ HCl) upsets the stomach and furthermore shows high intestinal absorption. Thus, development of pH sensitive hydrogels with sufficient mechanical strength will be good candidate to address this issue.MethodsHere, we developed pH sensitive itaconic acid-g-poly(acrylamide)/sterculia gum (IA-g-poly(AM)/sterculia gum) semi-interpenetrating network (semi-IPN) by free radical polymerization technique for intestinal delivery of CTZ HCL.ResultsOptimized formulation (I5) with 6% w/w IA showed negligible swelling at pH 1.2, and maximum swelling at pH 7.4. Solid state characterization of optimized formulation showed successful development of semi-IPN structure and incorporation of drug without any noticeable drug-carrier interaction. In vitro release study showed biphasic pH dependent release of CTZ HCl, where initial burst release was observed at acidic pH followed by sustained release at basic pH. Acute oral toxicity and histopathological studies confirmed the non-toxic nature of IA-g-poly(AM)/sterculia gum.ConclusionConclusively, developed biocompatible semi-IPN hydrogels with sufficient pH sensitivity and mechanical strength could serve as a potential carrier for intestinal delivery of CTZ HCL to maximize its absorption and reduce side effects.Graphical abstract Supplementary InformationThe online version contains supplementary material available at 10.1007/s40199-021-00395-8.  相似文献   
92.
Neonatal hypoxic-ischemic (HI) encephalopathy can lead to severe brain damage, and is a common cause of neurological handicaps in adulthood. HI can be resolved by the administration of an antioxidant such as 3-methyl-1-phenyl-2-pyrazolin-5-one (MCI-186). In the present study, we performed comprehensive gene expression and gene network analyses using a DNA microarray to elucidate the molecular events responsible for the selective vulnerability of neurons in neonatal HI brain insult and to examine the underlying mechanisms of the effect of MCI-186 on the pathophysiological events in this condition. We used the modified Levine method (Rice model), which has been widely used as an animal model of this condition. A large difference in gene expression was observed between the Rice model and the control group. Up- and downregulated genes after the HI brain insult were mainly related to immune responses and cell death, and neuronal activity, respectively. The effect of MCI-186 administration on gene expression was much less than and contrary to that of the HI brain insult, reflecting the protective effect of MCI-186 in HI brain insult.  相似文献   
93.
Tarsal ankylosis is described as a feature of advanced juvenile or rheumatoid arthritis. Ankylosis involving more then one tarsal segment is uncommon. Incidental reports of massive tarsal ankylosis have been described in a case of juvenile spondyloarthropathy, a case of familial tarsal ankylosis, and, more recently, it was discovered in a prehistoric skeleton dating back to the Iron Age. We describe a rare case of bilateral massive tarsal ankylosis, and the surgical intervention used to treat the condition, in a 21-year-old female with no other features of any known forms of arthritis and no family history of the condition.  相似文献   
94.
有1位于1996年实施右眼穿透性角膜移植术失败的双眼严重眼表化学伤的患者, 62岁,右眼视力手动,左眼视力光感。于2006-09-16/2007-02-07分别对右眼实施了异体角膜缘干细胞移植术和穿透性角膜移植术,经过术后5m的药物治疗观察,最终获得了右眼最佳矫正视力为6/30,角膜移植片透明,眼表得以重建,并未发现明显排斥迹象的良好效果。  相似文献   
95.
Two new prenylated flavones, artocarpones A and B (1 and 2), and seven known isoprenylated flavonoids, artonin A (3), cycloheterophyllin (4), artoindonesianin E (5), artoindonesianin R (6), heterophyllin (7), heteroflavanone C (8), and artoindonesianin A-2 (9), have been isolated from the stem bark of Artocarpus champeden. Their structures were determined by spectroscopic analysis. Among the compounds isolated, 8 had the most potent inhibitory activity against the growth of Plasmodium falciparum 3D7 clone, with an IC50 value of 1 nmol L−1.  相似文献   
96.
Anhydrous milkfat (AMF) was fractionated to obtain a series of high-melting milkfat fractions (HMF). Solid fat content (SFC) of HMF as determined by nuclear magnetic resonance (NMR) was in the range 37.6-43.6% and 21.2-27.5% measured at 20 and 30 degrees C, respectively. The HMF have a higher melting characteristic compared to AMF as analyzed by differential scanning calorimetry (DSC) with melting enthalpies of 92.2-105.0 J/g and melting peak temperatures of 39.3-41.5 degrees C. The AMF was also blended with soft palm stearin (SPOs and/or hard palm stearin (HPOs)) according to a three conventional component mixture design which providing suitable formulations for HMF. This represented three selected blends of AMF:SPOs:HPOs at three different proportions (70:15:15, 60:30:10 and 50:45:5), having SFC and DSC melting characteristics of HMF. The study revealed that higher-melting characteristics of AMF could be achieved equally well by using both fractionation and blending techniques.  相似文献   
97.
Aim:  The present study aimed to investigate the effect of the number and intensity of visits to the More Allied Health Services (MAHS) clinics and a change in glycosylated haemoglobin (HbA1c) levels in people with type 2 diabetes.
Methods:  Data on subjects accessing diabetes clinics in rural southern New South Wales were analysed retrospectively. Data included age at the end of the data collection period, sex, number and dates of visits to the MAHS dietitian and diabetes educator, weights and heights, HbA1c and cholesterol levels.
Results:  Sixty-four patient records were analysed. The median period of clinic attendance was 32.5 months; median number of combined visits to MAHS dietitian and diabetes educator was three. Older subjects were significantly more likely to show a reduction in HbA1c than younger subjects. Subjects visiting the MAHS program more regularly than once every eight months were significantly more likely to achieve a reduction in HbA1c than those who were seen by MAHS staff once every eight months or more. Sixty per cent of those subjects with four or more visits to the MAHS program showed a reduction in HbA1c, while 38% of those with fewer than four visits showed a reduction in HbA1c, but this association did not reach significance.
Conclusions:  Older subjects and those attending the MAHS diabetes clinics more intensively were significantly more likely to show a reduction in HbA1c than younger subjects and those attending the clinic once every eight months or more. Future, larger studies using additional outcome measures will allow for an improved evaluation of interventions by dietitians and diabetes educators for those with type 2 diabetes.  相似文献   
98.
目的:探讨糖尿病伴贫血患者在测定糖基化血红蛋白时,血红蛋白含量对糖基化血红蛋白测定的影响。方法:回顾性分析126例糖尿病伴贫血患者与132例糖尿病不伴贫血患者,糖基化血红蛋白测量的差异,用果糖胺与2周空腹血糖平均值做平行对照。结果:在相似果糖胺与空腹血糖平均值时,糖尿病伴有贫血的患者糖基化血红蛋白显著低于糖尿病不伴有贫血的患者(P<0.001)。结论:糖尿病伴贫血时血红蛋白浓度对糖基化血红蛋白测定有一定影响,临床对此结果应加以综合处理后进行评价。  相似文献   
99.
    
Paget’s disease is a metabolic bone disease characterized by excessive bone resorption and formation due to activated osteoclasts. Although Paget’s disease is a high bone turnover state, the excess bone that is formed lacks the structural stability of normal bone. Complications from Paget’s disease include deformity, fracture, and pain. Although still unclear, both prevalence and severity of Paget’s disease seem to be declining. Recent progress has focused on the environmental as well as genetic etiologies for this disease. Many studies indicate a role for viral infectious agents, whereas others point to a recently identified candidate gene on chromosome 18q. Therapy with bisphosphonate drugs is the treatment of choice. With newer and more powerful agents from this family now available, the majority of patients affected by Paget’s disease can achieve sustained remission and avoid complications.  相似文献   
100.
OBJECT: Pyridoxal-5-phosphate (PLP), the biologically active form of pyridoxine, can rescue neurons from death in vitro and in vivo. In the present project, the authors have studied whether MC-1, an analog of PLP, alone or in combination with the thrombolytic agent tissue plasminogen activator (tPA), can protect the brains of rats injured by ischemia. METHODS: Ischemic brain injury was induced in rats by injecting a preformed blood clot in the middle cerebral artery (MCA). Neurological deficits and infarct volumes caused by the embolus were measured to evaluate the effects of MC-1 on the ischemic injury. Systemic blood pressure and local brain blood flow were also monitored. Administration of different doses of MC-1 1 hour after embolization significantly reduced the infarct volume and improved functional recovery. Injection of MC-1 (40 mg/kg) at 3 or 6 hours after embolization also reduced the volume of the infarct significantly and improved functional recovery. Combined treatment with MC-1 and tPA was also neuroprotective, although it was not superior to treatment involving either MC-1 or tPA alone. Treatment with MC-1 did not result in significant changes in either systemic blood pressure or local blood flow in the ischemic brain. CONCLUSIONS: These data support the hypothesis that in the focal embolic stroke model in rats MC-1 is a neuroprotective agent. The neuroprotection this compound provides still exists when MC-1 administration is delayed up to 6 hours after ischemic injury.  相似文献   
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