Protective effect of pinocembrin from Penthorum chinense Pursh on hepatic ischemia reperfusion injury via regulating HMGB1/TLR4 signal pathway

Hepatic ischemia–reperfusion injury (HIRI) is of common occurrence during liver surgery and transplantation. Pinocembrin (PIN) is a kind of flavonoid monomer extracted from the local traditional Chinese medicine Penthorum chinense Pursh (P. chinense). However, the effect of PIN on HIRI has not determined. We investigated the protective effect and potential mechanism of PIN against HIRI. Model mice were subjected to partial liver ischemia for 60 min, experimental mice were pretreated with PIN orally for 7 days, and H₂O₂-induced oxidative damage model in AML12 hepatic cells was established in vitro. Histopathologic analysis and serum biochemical levels revealed that PIN had hepatoprotective activities against HIRI. The variation of GSH, SOD, MDA, and ROS levels indicated that PIN treatments attenuated oxidative stress in tissue. PIN pretreatment obviously ameliorated apoptosis, and restrained the expression of HMGB1 and TLR4 in vivo. In vitro, compared with H₂O₂ group, the contents of ROS, mitochondrial membrane potential, apoptotic cells, and Bcl-2 protein were decreased, while the Bax protein expression was increased. Moreover, HMGB-1 small interfering RNA test and western blotting showed that PIN pretreatment reduced HMGB1 and TLR4 protein levels. In conclusion, PIN pretreatment effectively protected hepatocytes from HIRI and inhibited the HMGB1/TLR4 signaling pathway.     

The association between caudal block and urethroplasty complications of distal tubularized incised plate repair: experience from a South China National Children’s Medical Center

BackgroundThe effect of caudal block (CB) on the incidence of urethroplasty complications in hypospadias repair remains controversial. The evidence is conflicting, and some confounding bias issues need to be addressed. We sought to study a more homogenous group of distal hypospadias patients undergoing primary tubularized incised plate (TIP) repair by a senior pediatric urology surgeon in the past 2 years to examine the relationship between urethroplasty complications and the use of CB.MethodsWe reviewed our database to identify consecutive patients who had undergone hypospadias repairs by a senior director surgeon at our Center between January 2018 and November 2020. To be eligible to participate in the study, patients had to meet the following inclusion criteria: (I) have distal hypospadias; (II) have undergone a primary TIP repair; and (III) have attended follow-up appointments for a minimum period of 6 months. The primary outcome was the development of urethroplasty complications during the follow-up period. The principal variable of interest was whether or not CB was used perioperatively. The patients were categorized into a CB group (general anesthesia combined with CB) or a control group (general anesthesia only). Other potential risk factors were analyzed, including patient age at operation, patient weight, glans width, and the length of the urethral plate defect.ResultsThirty (12.2%) of the distal patients developed postoperative surgical complications. The postoperative surgical complication rates were similar between the different anesthesia groups. Weight, the length of the urethral plate length, and glans width did not contribute to the risk. Age was the only independent risk factor for postoperative surgical complications, and the complication rates increased in older patients.ConclusionsOur data from consecutive TIP repairs in distal hypospadias patients indicated no association between the use of CB anesthesia and the postoperative urethroplasty complication rate. Patients who were older in age when they underwent surgery had a higher risk of complications.     

An Environmental Dilemma for China During the COVID-19 Pandemic: The Explosion of Disposable Plastic Wastes

Plastic pollution control has been on top of the political agenda in China. In January 2020, China announced a phased ban on the production and usage of various types of single-use plastics as a solution to environmental pollution problems. However, the outbreak of COVID-19 seems to be a new obstacle to the ban on single-use plastic products. To basically satisfied the daily necessities and contain the spread of SARS-CoV-2 under the background of the regular epidemic prevention and control in China, online ordering, contactless delivery and wearing mask have become an important and feasible way of daily life. However, the unrestrained use of disposable plastic bags, lunch boxes and masks within the nationwide quarantine leads to hundreds of millions of plastics wastes every day. The potential environmental pollution caused by the use of disposable plastic products during the pandemic should arouse social concern. The Chinese government should manage environmental protection in parallel with anti-pandemic endeavors as the situation of the pandemic evolves.

     

磁处理水对抗癌药物的解毒作用

我们的实验发现，磁处理水对环磷酰胺等五种抗癌药物的毒性具有不同程度的缓解作用，能增加小鼠的存活率，能降低药物引起的白细胞减少。对目前癌化疗中使用率最高的环磷酰胺，其作用最明显。     

GAG-augmented polysaccharide hydrogel: a novel biocompatible and biodegradable material to support chondrogenesis

The quality of articular cartilage engineered using a cell-polymer construct depends, in part, on the chemical composition of the biomaterial and whether that biomaterial can support the chondrocytic phenotype. Acknowledging the supportive influence of tissue-specific matrix molecules on the chondrocytic phenotype, we have combined chondroitin sulfate-A (CSA) and chitosan, a glycosaminoglycan (GAG) analog, to develop a novel biomaterial to support chondrogenesis. Chitosan is a polycationic repeating monosaccharide of beta-1,4-linked glucosamine monomers with randomly located N-acetyl glucosamine units. Chitosan may be combined with the polyanionic CSA such that ionic crosslinking results in hydrogel formation. Bovine primary articular chondrocytes, when seeded onto a thin layer of CSA-chitosan, form discrete, focal adhesions to the material and maintain many characteristics of the differentiated chondrocytic phenotype, including round morphology, limited mitosis, collagen type II, and proteoglycan production. Our findings suggest CSA-chitosan may be well suited as a carrier material for the transplant of autologous chondrocytes or as a scaffold for the tissue engineering of cartilage-like tissue.     

应用激光电泳技术对MA737小鼠乳腺癌细胞膜表面电荷特性的研究

本工作应用激光多普勒电泳技术对ＭＡ７３７小鼠乳腺癌细胞膜表面电荷特性及高温（４２．５℃）对癌细胞的热效应进行了深入的研究。结果发现，ＭＡ７３７癌细胞的电泳迁移率（ＥＰＭ）明显高于相应正常细胞的ＥＰＭ（约２０％），表明癌细胞表面负电荷增高；实验发现唾液酸可能是ＭＡ７３７癌细胞膜表主要负电基团的来源之一。研究还发现，ＭＡ７３７癌细胞的热敏性比相应的正常细胞强，随高温受热时间的延长，癌细胞的ＥＰＭ呈下降趋势。     

球囊导管损伤后早期动脉平滑肌细胞的增殖

目的：研究动脉硬化早期中膜与内膜平滑肌细胞的增殖。方法：球囊导管损伤大鼠的颈总动脉后在电镜和光镜下观察其形态和生化指标变化。结果：术后24h 5-溴脱氧尿嘧啶尿苷阳性平滑肌细胞出现,阳性细胞率分别于术后第2,5d出现高峰。术后第2,3d迁移细胞的出现率最高。术后第3d,88.8%迁移细胞增殖细胞核抗原阳性。透射电子显微镜下,术后第3d中膜平滑肌细胞特别是内层的为合成型,并且与细胞外基质连接稀疏,基底膜、胶原纤维和弹性纤维被消失。结论：动脉损伤后,中膜平滑肌细胞呈高增殖性,由收缩型转变为合成型,与细胞外基质的结合性降低,中膜弹性纤维、胶原纤维被消化,增生活跃的细胞向内膜的迁移性增高。迁移至内膜的平滑肌细胞呈高增殖性。     

淋病奈瑟氏菌中国流行株gyrA和parC基因与喹诺酮类耐药性的相关性

目的　调查中国地区淋病奈瑟氏菌 (NG)对喹诺酮类的耐药性状况 ,探讨高水平耐药的基因突变株对喹诺酮类耐药机制的作用 .方法　对 9a来临床分离保存淋球菌流行株进行了体外环丙沙星 (CIP)药敏实验 .筛选出 76株高水平CIP耐药株 ,通过 PCR扩增了其中的 1 8株 NG的 gyr A和par C喹诺酮耐药决定区基因 ,并对扩增子直接测序 .通过N he I酶切、脉冲电场凝胶电泳 (PFEG)分析了这些菌株的遗传关系 .结果　环丙沙星的耐药检出率有逐年增高的趋势 ,MIC≥ 1 .0 mg· L- 1的菌株由 1 993年的 5 .1 %上升到 2 0 0 1年的 2 1 .4% .对照组中的 1 8株敏感菌只有两株发生了 gyr A的单一突变 ,未发现 par C变异 ;而耐药组中 89% (1 6 )菌株的gyr A发生了 Ser- 91向 Phe的单一突变株或 (和 ) par C的双突变 .88.9% (1 5 )的菌株的 gyr A发生了 Ser- 91向 Phe和 Asp-95向 Gly的突变 .在发生 par C突变中 72 %属于 Asp- 86向Asn突变 .PFEG分析发现 1 0株具有完全一致的 gyr A和par C突变模式 .同时也发现来自不同地区的菌株的 PFEG指纹图是不同的 .结论　研究表明 ,在中国 NG流行株对喹诺酮类耐药率呈增长趋势 ;NG流行株对喹诺酮产生耐药性与gyr A和 par C基因双重突变有着密切的关系