Dibucaine in Ionic-Gradient Liposomes: Biophysical,Toxicological, and Activity Characterization

Administration of local anesthetics is one of the most effective pain control techniques for postoperative analgesia. However, anesthetic agents easily diffuse into the injection site, limiting the time of anesthesia. One approach to prolong analgesia is to entrap local anesthetic agents in nanostructured carriers (e.g., liposomes). Here, we report that using an ammonium sulphate gradient was the best strategy to improve the encapsulation (62.6%) of dibucaine (DBC) into liposomes. Light scattering and nanotracking analyses were used to characterize vesicle properties, such as, size, polydispersity, zeta potentials, and number. In vitro kinetic experiments revealed the sustained release of DBC (50% in 7 h) from the liposomes. In addition, in vitro (3T3 cells in culture) and in vivo (zebrafish) toxicity assays revealed that ionic-gradient liposomes were able to reduce DBC cyto/cardiotoxicity and morphological changes in zebrafish larvae. Moreover, the anesthesia time attained after infiltrative administration in mice was longer with encapsulated DBC (27 h) than that with free DBC (11 h), at 320 μM (0.012%), confirming it as a promising long-acting liposome formulation for parenteral drug administration of DBC.     

Effect of correcting for gestational age at birth on population prevalence of early childhood undernutrition

Background

Postmenstrual and/or gestational age-corrected age (CA) is required to apply child growth standards to children born preterm (< 37 weeks gestational age). Yet, CA is rarely used in epidemiologic studies in low- and middle-income countries (LMICs), which may bias population estimates of childhood undernutrition. To evaluate the effect of accounting for GA in the application of growth standards, we used GA-specific standards at birth (INTERGROWTH-21st newborn size standards) in conjunction with CA for preterm-born children in the application of World Health Organization Child Growth Standards postnatally (referred to as ‘CA’ strategy) versus postnatal age for all children, to estimate mean length-for-age (LAZ) and weight-for-age (WAZ) z scores at 0, 3, 12, 24, and 48-months of age in the 2004 Pelotas (Brazil) Birth Cohort.

Results

At birth (n = 4066), mean LAZ was higher and the prevalence of stunting (LAZ < ?2) was lower using CA versus postnatal age (mean ± SD): ? 0.36 ± 1.19 versus ? 0.67 ± 1.32; and 8.3 versus 11.6%, respectively. Odds ratio (OR) and population attributable risk (PAR) of stunting due to preterm birth were attenuated and changed inferences using CA versus postnatal age at birth [OR, 95% confidence interval (CI): 1.32 (95% CI 0.95, 1.82) vs 14.7 (95% CI 11.7, 18.4); PAR 3.1 vs 42.9%]; differences in inferences persisted at 3-months. At 12, 24, and 48-months, preterm birth was associated with stunting, but ORs/PARs remained attenuated using CA compared to postnatal age. Findings were similar for weight-for-age z scores.

Conclusions

Population-based epidemiologic studies in LMICs in which GA is unused or unavailable may overestimate the prevalence of early childhood undernutrition and inflate the fraction of undernutrition attributable to preterm birth.

     

Visceral adipose tissue is more strongly associated with insulin resistance than subcutaneous adipose tissue in Chinese subjects with pre-diabetes

Aims: To investigate the value of visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) in a cohort of a community’s residents who were diagnosed as pre-diabetes, and to evaluate the association of VAT and SAT with insulin resistance.

Methods: This study was based on cross-sectional analysis of data from 107 adults. VAT and SAT were assessed by computed tomography. Insulin resistance was defined by homeostasis model assessment of insulin resistance >2.69. The relationship of VAT and SAT with insulin resistance were examined by linear regression. Logistic regression was used to analyze the association of VAT and SAT with insulin resistance.

Results: A total of 87 subjects had VAT ≥100?cm². Thirty-six out of 107 (33.6%) subjects were detected to have insulin resistance, 71 were normal (66.4%), and all had insulin resistance with VAT ≥100?cm². VAT (r?=?0.378, p?r?=?0.357, p?p?=?.003), but that of SAT was lost.

Conclusion: Pre-diabetic subjects with insulin resistance had elevated levels of VAT. VAT was more strongly associated with insulin resistance than SAT in Chinese subjects with pre-diabetes.     

Demonstration of pharmaceutical tablet coating process by injection molding technology

We demonstrate the coating of tablets using an injection molding (IM) process that has advantage of being solvent free and can provide precision coat features. The selected core tablets comprising 10% w/w griseofulvin were prepared by an integrated hot melt extrusion-injection molding (HME-IM) process. Coating trials were conducted on a vertical injection mold machine. Polyethylene glycol and polyethylene oxide based hot melt extruded coat compositions were used. Tablet coating process feasibility was successfully demonstrated using different coating mold designs (with both overlapping and non-overlapping coatings at the weld) and coat thicknesses of 150 and 300?μm. The resultant coated tablets had acceptable appearance, seal at the weld, and immediate drug release profile (with an acceptable lag time). Since IM is a continuous process, this study opens opportunities to develop HME-IM continuous processes for transforming powder to coated tablets.     

Loratadine augments emotional blushing

The aim of this study was to determine whether loratadine, a selective inverse agonist of peripheral histamine H₁ receptors, would reduce emotional blushing. Loratadine (10?mg) or placebo was administered orally one hour before 31 healthy participants sang a children's nursery rhyme to evoke embarrassment and blushing. Skin blood flow was monitored via a laser Doppler probe attached to the cheek. Increases in facial blood flow while participants sang were greater in the loratadine than the placebo group (mean increase?±?standard deviation 71?±?52% in the loratadine group versus 35?±?37%, p?=?.036). However, perceptions of blushing were similar in both groups. These findings suggest that loratadine augmented blushing rather than inhibiting it. Thus, histamine released during blushing may inhibit acute increases in facial blood flow by evoking H₁ receptor-mediated vasoconstriction.     

Effects of squalene on expression of LDLR in HepG2 cells and its mechanism北大核心CSCD

Aim To investigate the effect of squalene on LDLR expression in HepG2 cells and its mechanism of down-regulated cholesterol. Methods The proliferation of HepG2 cells exposed to squalene at different concentrations was measured by MTT assay. The effect of squalene on the expression of LDLR in HepG2 cells was measured by flow cytometry and fluorescence mi-croscopy. The effect of different concentrations of squalene on the interaction between SCAP and Insig2, two key protein molecules of SREBP pathway, was assayed by FRET technology. Results MTT results showed that squalene had inhibitory effect on the proliferation of HepG2 cells in a dose-dependent manner. Flow cytometry and fluorescence microscopy results showed that squalene enhanced LDLR expression in HepG2 cells compared with the control group. The results of FRET technology revealed that compared with model control group, the YFP fluorescence value in Squalene group dramatically declined, and the YFP fluorescence value of each drug group decreased with the range of 5-25 |xmol L1 squalene concentration. Conclusions Squalene may promote the expression of LDLR in HepG2 cells through inhibiting the interaction between SCAP and Insig2 proteins in SREBP pathway, which may confirm that squalene is a potential novel drug for the down-regulation of cholesterol level. © 2018 Publication Centre of Anhui Medical University. All rights reserved.     

苍耳子药材的HPLC特征图谱研究

摘 要 目的：建立苍耳子药材的HPLC特征图谱,为评价不同产地苍耳子的质量提供参考。方法: 采用Alltima C18（250 mm×4.6 mm,5 μm）,流动相乙腈 0.1%磷酸溶液梯度洗脱,流速：0.8 ml·min^-1,检测波长：278 nm,柱温：25 ℃,对来自河南、吉林、安徽等地共47批苍耳子样品运用“中药指纹图谱相似度评价系统”进行分析。 结果:以绿原酸为参照峰,初步构建了由5个特征峰组成的苍耳子HPLC 特征图谱。结论:该方法简便、可靠,为苍耳子药材的质量控制提供了有效的评价方法。