Preparation of rabbit anti-rat LRRN3 polyclonal antibody and study of its expression

BACKGROUND： Studies have shown that the Repeat superfamily, could be related to neural LRRN3, a member of the Neuron Leucine-Rich development, differentiation, information transmission, and other functions, but most studies have focused on nucleic acid levels and few have reported on LRRN3 protein levels. OBJECTIVE： To prepare rabbit anti-rat LRRN3 polyclonal antibody and to observe protein tissue expression profiles. DESIGN, TIME AND SEI-rlNG： In vitro, molecular, biological experiments were performed from October 2007 to April 2009 in Laboratory of Neurobiology at Xiangya School of Medicine, Central South University. MATERIALS： Immunization antigen, namely rat MaI-LRRN3C-His recombinant protein, was provided by the Laboratory of Neurobiology at Xiangya School of Medicine, Central South University. METHODS： Rat Mal-LRRN3C-His recombinant protein was used to immunize male, New Zealand rabbits, and rabbit anti-rat LRRN3 polyclonal antibody was prepared. MAIN OUTCOME MEASURES： Antibody purification was conducted using Protein A affinity chromatography, and the LRRN3 anti-serum titer was identified using enzyme-linked immunosorbent assay. Immunohistochemical techniques and Western blot preliminary tests were used to determine LRRN3 protein expression profiles in adult rats. RESULTS： A highly purified rabbit anti-rat LRRN3 polyclonal antibody was obtained. Western Blot results from rat brain total protein revealed a band at 79 kD, which was consistent with the size of LRRN3. Immunohistochemistry results showed that protein was mainly expressed in the central nervous system, and no significant positive signals were observed in other tissues. Positive cells included neurons of cerebral cortex and hippocampal dentate gyrus granule cell layer, and cerebellar Purkinje cells. There was no positive expression in glial cells. CONCLUSION： Rabbit anti-rat LRRN3 polyclonal antibody was successfully prepared at a high purity from the prokaryotic-expressed MaI-LRRN3C-His recombinant protein, which served as an antigen. Rat LRRN3 protein was primarily expressed in cerebral cortex neurons, hippocampal dentate gyrus granule cell layer neurons, and cerebellar Purkinje cells.

Clinical diagnosis and treatment of alpha-fetoprotein-negative small hepatic lesions

Objective： We examined 103 cases over the last five years and discussed diagnosis and treatment of alpha- fetoprotein （AFP）-negative small hepatic lesions. Background： Small hepatic lesions （less than 2 cm in diameter） usually have no typical imaging characteristics and therefore are difficult to diagnose, especially when AFP tests provide a negative result. Methods： A total of 103 patients with AFP-negative small hepatic lesions from January 2003 to December 2008 were retrospectively reviewed. Differential diagnosis was performed by digital subtraction angiography （DSA）, dynamic contrast-enhanced magnetic resonance imaging （DCE-MRI）, contrast-enhanced ultrasound （CEUS）, or positron emission tomography-computed tomography （PET-CT） based on the multiplicity of lesions. Ninety-four patients with suspected cancers underwent partial hepatectomy. Clinical data were collected from hospital records and follow-up questionnaires. Results： Hepatocellular carcinoma （HCC） diagnostic sensitivity of DSA, DCE-MRI, CEUS and PET-CT was 88.2%, 93.9%, 88.9% and 88.9%, respectively. The surgery-related complication rate was 6.4%. Prognosis was good, with 1- and 3-year survival rates of 98.8% and 76.1%, respectively. Conclusions： DSA, DCE-MRI, CEUS and PET-CT are valuable for diagnosis of small hepatic lesions. Partial hepatectomy is a preferred surgical procedure. Surgery for small liver cancers usually has little risk and good prognosis, therefore it can be actively applied in suspected HCC cases.

抗新冠病毒候选药物发现的重要来源——茶叶

新型冠状病毒(SARS-CoV-2)引发的新冠肺炎(COVID-19)在全球范围内广泛传播,严重威胁人类的生命健康安全。茶叶作为一种药食同源的产品,其所含的多种成分具有阻止病毒入侵宿主细胞、抑制病毒复制、增强机体固有免疫和细胞免疫应答的活性,可能发挥抗新冠病毒作用。本文系统总结了绿茶、黄茶、白茶、乌龙茶、红茶、黑茶的成分与功效特征,系统综述了茶叶中的主要抗病毒活性成分,包括(-)-表没食子儿茶素没食子酸酯,(-)-没食子儿茶素没食子酸酯,单宁酸,oolonghomobisflavan A,茶黄素和白毫银针黄酮等。其中,(-)-表没食子儿茶素没食子酸酯有效抑制病毒入侵、复制,调节炎症内环境稳态,发挥抗病毒和免疫调节的双重作用,被认为是抗病毒潜在的抑制剂,该化合物作为抗SARS-CoV-2病毒有效的先导化合物,值得进一步研究开发。

Self-assembly of phosphorylated peptide driven by Dy^(3+)

Nature chooses phosphorylation as a key modification to modulate and program the functions of proteins.Various phosphorylated peptides(PPs)have been widely identified and investigated by biologists,but the possibility that PPs could become a building unit for artificial materials is neglected.Here we report for the first time a supramolecular assembly of PPs with the assistance of dysprosium ions(Dy^(3+)).Dy^(3+)bridges multiple phosphate groups in double-phosphorylated peptides(di-PPs),and braid these peptide chains into nanofibers.The assembly occurs inside nanochannels and blocks the channels,leading to prominent“ON–OFF”switching in transmembrane ionic current.The di-PPs’assembling process could be dynamically regulated by the addition or deletion of phosphate groups under the control of kinases or phosphatases.This study proves the huge potential of PPs being utilized as materials via self-assembling,which will promote the design of novel bio-inspired artificial materials and devices.

Neoplastic polyps in gallbladder: a retrospective study to determine risk factors and treatment strategy for gallbladder polyps

Background:Preoperative differentiation of malignant and premalignant gallbladder polyps(GBPs)from benign lesions is a key imperative to guide treatment decision-making.We aimed to characterize the various types of GBPs and sought to identify the risk factors for neoplastic polyps.Our findings may help optimize treatment strategy.Methods:Retrospective analysis of 686 patients with post-cholecystectomy pathologically-proven GBPs between January 2003 and December 2016.The patients were classified into non-neoplastic polyp group,benign neoplastic polyp group,and adenoma canceration group.Clinical features,ultrasound findings,and results of laboratory investigations and histopathological examination were reviewed and compared between the groups.Results:Out of 686 patients,542(79.0%)had non-neoplastic polyps,134(19.5%)had neoplastic polyps,and 10(1.5%)had adenoma canceration.The mean age was 46.06±12.12 years;383(55.8%)patients were female.The median(25th percentile,75th percentile)time between diagnosis and surgery in the cholesterol polyp group[24(3.5,60)months]was significantly longer than that in adenoma[12(2,60)months]and adenoma canceration[5(0.475,12)months]groups.The mean diameter was 1.14±0.61 cm(range,0.5–8.4 cm).Three hundred twelve(45.5%)patients had solitary polyps and intralesional blood flow was observed in 41(6.0%)patients.On univariate analysis,age>49.5 years,polyp size>1.15 cm,solitary polyp,intralesional blood flow,absence of symptoms,and lack of cholecystitis showed a significant association with adenoma.On multivariate analysis,polyp size(>1.15 cm),intralesional blood flow,and lack of cholecystitis were independent predictors of adenoma.Conclusions:Polyp size>1.15 cm,intralesional blood flow,and lack of cholecystitis were predictors of neoplastic polyps.Malignant transformation of adenoma may occur over a relatively short time.

Lymphovascular tumor embolus might be a risk factor for peritoneal metastasis after laparoscopic hepatectomy for hepatocellular carcinoma

Laparoscopic hepatectomy has been applied to treat hepatocellular carcinoma(HCC)(1-7).Previous reports show that laparoscopic procedure is as safe as the open procedure,and the long-term results are also inspiring.However,there are still doubts about whether laparoscopic procedure would increase the possibility of peritoneal metastasis and what the risk factors may be.This issue has not been found or mentioned in these recent reports.However,we here present two patients with HCC who developed peritoneal metastasis after laparoscopic hepatectomy.Risk factors for peritoneal metastasis after laparoscopic hepatectomy merits further study.

Hidden-mortality risk among patients deemed“low-risk”following high-risk operations

In the surgical field,growing attention has been paid to the identification of patients with a particularly high predisposition to postoperative morbidity and mortality following high-risk operations.The hepatopancreatic operation is one of the most complex surgical procedures,and it places a heavy burden on individuals and public health systems.The latest statistics reveal that an estimated 40.5%of patients undergoing hepatopancreatic operation have experienced at least 1 postoperative complication,and about 1.3%of these patients died within 30 days(1).Given the high burden associated with high-risk operations,research efforts have shifted toward the identification and management of patients at the highest risk of morbidity and mortality,but have overlooked the hidden risk among patients labeled“low risk”by multiple prognostic tools(2,3).Whether such hidden risks merit special consideration or can be overlooked is currently an open question and the subject of ongoing debate.