Optimization,in vitro release and toxicity evaluation of novel pH sensitive itaconic acid-g-poly(acrylamide)/sterculia gum semi-interpenetrating networks

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.     

New prenylated flavones from <Emphasis Type="Italic">Artocarpus champeden</Emphasis>, and their antimalarial activity in vitro

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.     

Physical characteristics of modified milkfat in high-melting fat preparation

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.     

Latent activity of curcumin against leishmaniasis in vitro

In this study the anti-proliferative effect of curcumin (curcuma longa) that is the active ingredient of ground dried rhizome has been studied against three local and three reference leishmanial strains, Leishmania major, Leishmania tropica and Leishmania infantum (Pakistani isolate). Curcumin has shown an average IC50 of 5.3 microM against promastigotes of various leishmanial strains which is much lower as compared with pentamidine that is one of the basic treatments against leishmaniasis. The main draw back attributed to these assays performed on promastigotes is the heterogeneity of results compared with those obtained with intracellular amastigotes or with in vivo effect. We also tested activity of curcumin against axenic amastigote like cells (AALC) of L. major strain (MHOM/PK/88/DESTO). Curcumin proves to be far more potent then pentamidine against AALC which further strengthens the fact about its leishmaniacidal activity.     

Does intervention by the dietitian and diabetes educator of a More Allied Health Services program improve glycosylated haemoglobin levels for those with type 2 diabetes? Implications for rural dietetic practice

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.     

糖尿病伴贫血对糖基化血红蛋白测量的影响

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。     

Role of MC-1 alone and in combination with tissue plasminogen activator in focal ischemic brain injury in rats

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.