Deletion of Krüppel-like factor-4 promotes axonal regeneration in mammals

Axonal regeneration plays an important role in functional recovery after nervous system damage. However, after axonal injury in mammals, regeneration is often poor. The deletion of Krüppel-like factor-4 (Klf4) has been shown to promote axonal regeneration in retinal ganglion cells. However, the effects of Klf4 deletion on the corticospinal tract and peripheral nervous system are unknown. In this study, using a mouse model of sciatic nerve injury, we show that the expression of Klf4 in dorsal root ganglion sensory neurons was significantly reduced after peripheral axotomy, suggesting that the regeneration of the sciatic nerve is associated with Klf4. In vitro, dorsal root ganglion sensory neurons with Klf4 knockout exhibited significantly enhanced axonal regeneration. Furthermore, the regeneration of the sciatic nerve was enhanced in vivo following Klf4 knockout. Finally, AAV-Cre virus was used to knockout the Klf4 gene in the cortex. The deletion of Klf4 enhanced regeneration of the corticospinal tract in mice with spinal cord injury. Together, our findings suggest that regulating KLF4 activity in neurons is a potential strategy for promoting axonal regeneration and functional recovery after nervous system injury. This study was approved by the Animal Ethics Committee at Soochow University, China (approval No. SUDA20200316A01).

Chinese Library Classification No.R456; R741; Q344+.14     

Pituitary Adenylate Cyclase-Activating Polypeptide Attenuates Brain Edema by Protecting Blood–Brain Barrier and Glymphatic System After Subarachnoid Hemorrhage in Rats

Brain edema is a vital contributor to early brain injury after subarachnoid hemorrhage (SAH), which is responsible for prolonged hospitalization and poor outcomes. Pharmacological therapeutic targets on edema formation have been the focus of research for decades. Pituitary adenylate cyclase-activating polypeptide (PACAP) has been shown to participate in neural development and brain injury. Here, we used PACAP knockout CRISPR to demonstrate that endogenous PACAP plays an endogenous neuroprotective role against brain edema formation after SAH in rats. The exogenous PACAP treatment provided both short- and long-term neurological benefits by preserving the function of the blood–brain barrier and glymphatic system after SAH. Pretreatment of inhibitors of PACAP receptors showed that the PACAP-involved anti-edema effect and neuroprotection after SAH was facilitated by the selective PACAP receptor (PAC1). Further administration of adenylyl cyclase (AC) inhibitor and sulfonylurea receptor 1 (SUR1) CRISPR activator suggested that the AC–cyclic adenosine monophosphate (cAMP)–protein kinase A (PKA) axis participated in PACAP signaling after SAH, which inhibited the expression of edema-related proteins, SUR1 and aquaporin-4 (AQP4), through SUR1 phosphorylation. Thus, PACAP may serve as a potential clinical treatment to alleviate brain edema in patients with SAH.Electronic supplementary materialThe online version of this article (10.1007/s13311-020-00925-3) contains supplementary material, which is available to authorized users.Key Words: Subarachnoid hemorrhage, brain edema, pituitary adenylate cyclase-activating polypeptide, blood–brain barrier, glymphatic system     

无创产前检测联合孕妇血清可溶性转铁蛋白受体、生长分化因子-15、红细胞体积分布宽度变异系数检测对胎儿β-地中海贫血的诊断价值研究

目的探讨无创产前检测(NIPT)联合孕妇血清可溶性转铁蛋白受体(sTfR)、生长分化因子(GDF)-15、红细胞体积分布宽度变异系数(RDW-CV)检测，对胎儿β-地中海贫血的诊断价值。 方法选择2017年1月至2018年6月，于自贡市妇幼保健院接受羊膜腔穿刺术确诊胎儿为β-地中海贫血的120例孕妇为研究对象。根据其妊娠胎儿的β-地中海贫血轻、中、重型，将其分别纳入轻型组(n＝48)、中型组(n＝40)与重型组(n＝32)。选取同期于本院建卡进行常规产前检查，并且妊娠胎儿发育正常的100例健康孕妇作为对照，纳入对照组。采集4组孕妇空腹肘静脉血，提取孕妇外周血浆中胎儿细胞外游离DNA(cfDNA)，采用2次PCR方法扩增后，采用反向斑点杂交方法检测胎儿β-地中海贫血基因。采用酶联免疫吸附测定法，测定4组孕妇血清sTfR、GDF-15、RDW-CV水平。对4组孕妇血清sTfR、GDF-15与RDW-CV水平分别总体比较，采用单因素方差分析，进一步两两比较，采用最小显著性差异(LSD)-t检验。与胎儿β-地中海贫血诊断"金标准"比较，计算NIPT联合孕妇血清sTfR、GDF-15、RDW-CV水平及这4项指标单独检测，对于胎儿β-地中海贫血诊断的敏感度、特异度、粗符合率、阳性预测值、阴性预测值。本研究严格按照2013年修订的《世界医学协会赫尔辛基宣言》要求进行。4组孕妇年龄及其妊娠胎儿的胎龄等一般临床资料比较，差异均无统计学意义(P>0.05)。 结果①夫妻双方β-地中海贫血基因型相同的40例孕妇中，NIPT与羊膜腔穿刺术对于胎儿β-地中海贫血诊断的符合率为90.0%(36/40)；夫妻双方β-地中海贫血基因型不同的80例孕妇中，上述2种方法对于胎儿β-地中海贫血诊断的符合率亦为90. 0%(72/80)。②4组孕妇血清sTfR、GDF-15、RDW-CV水平分别总体比较，差异均有统计学意义(F＝2 283.445、323.181、45.900，P均<0.001)，进一步两两比较，任意2组孕妇血清sTfR、GDF-15、RDW-CV水平比较，差异均有统计学意义(P<0.05)，并且孕妇血清sTfR、GDF-15、RDW-CV水平随着β-地中海贫血胎儿严重程度增加而逐渐升高。③NIPT联合孕妇血清sTfR、GDF-15、RDW-CV水平检测，对于胎儿β-地中海贫血诊断的敏感度、特异度、粗符合率、阳性预测值与阴性预测值，分别为86.7%、88.0%、87.3%、86.7%与84.6%，其特异度与阳性预测值，均显著高于单独检测孕妇血清sTfR、GDF-15、RDW-CV水平，并且差异均有统计学意义(与孕妇血清sTfR水平比较：χ²＝8.866、5.301，P＝0.003、0.021；与孕妇血清GDF-15水平比较：χ²＝9.765、5.929，P＝0.002、0.015；与孕妇血清RDW-CV水平比较：χ²＝7.167、4.327，P＝0.007、0.038)。 结论孕妇血清sTfR、GDF-15、RDW-CV可能成为诊断胎儿β-地中海贫血的生物标志物，NIPT联合这3项指标检测，可提高诊断胎儿β-地中海贫血的特异度与阳性预测值。由于本研究纳入样本量相对较小，NIPT联合孕妇血清sTfR、GDF-15、RDW-CV水平，对胎儿β-地中海贫血的诊断价值，仍然有待进一步研究、证实。     

社区常见恶性肿瘤筛查研究

目的探寻一种简便的恶性肿瘤初筛自查方法。方法将人体肿瘤分为三类:体表肿瘤约占15％;空腔脏器肿瘤占65％;深层实体脏器肿瘤20％。通过科普宣传教育,让群众学会自查体表部位肿瘤,每年用自查盒助查各空腔脏器有无微量出血,隐血阳性时,去医院进一步精查。北京部分大学选40～70岁居民1万人,分成试验组、对照组各5千人。结果试验四年后:试验组共查出79例癌,年平均癌检出率482.5人/10万,癌死亡率为12.2/10万;对照组癌死亡率206.2人/10万,两组有显著性差异。在癌症高发区,同时作扩大普查试验:广东四会市肿瘤所,在门诊普查1669人,检出25例癌,鼻咽癌占24例。1999～2000年,江苏省食管胃癌高发区,普查近8万人,检出480例癌。加上“九五”以前的普查统计,用秦氏自查盒已筛查431075人,检出1272例癌,癌前病变1万多例。结论试验证明该方案设计合理,在当前是一种最简便的恶性肿瘤初筛自查方法。     

饲喂乳源免疫调节肽对大鼠生长和免疫的影响

目的探讨乳源免疫调节肽(PGPIPN)对大鼠生长和免疫的影响。方法取42只40日龄的SD大鼠(♀♂各半)随机分为两个实验组和一个对照组(每组14只且♀♂相等,分开饲养)。预饲1周后,实验组Ⅰ和Ⅱ分别被灌喂2.5×10-3g/L和2.5×10-2g/L免疫调节肽,对照组灌喂生理盐水,记录大鼠日采食量和体重。饲养1个月后检测对照组和实验组大鼠淋巴细胞转化、红细胞免疫、巨噬细胞吞噬、日采食量和体重等差别。结果乳源免疫调节肽对大鼠腹腔巨噬细胞吞噬和红细胞免疫有显著促进功能(P<0.05);而对淋巴细胞转化作用有增长的趋势,但未达到显著水平(P>0.05)。与对照组相比,实验组Ⅱ的大鼠日采食量显著地增加(P<0.05),♀♂大鼠分别提高了10.95%和8.03%;增重率有提高的趋势,♀♂大鼠增重率分别提高了5.13%和7.10%,但均未达显著水平(P>0.05)。实验组Ⅰ的大鼠,其日采食量和增重与对照组相比均变化不大。结论乳源免疫调节肽能促进机体的免疫功能,提高其免疫力;增加日采食量。     

Chloride channel 3 (CIC-3) predicts the tumor size in hepatocarcinoma

Chloride channel 3 (CIC-3) has been suggested to be implicated in the carcinogenesis though; it still remains ill understood in hepatocarcinoma, especially in terms of clinicopathological meaning of its expression. Given this, herein, to understand the clinicopathological significance of CIC-3 expression in hepatocarcinoma, Immunohistochemistry was performed to examine the level of CIC-3, followed by statistical analysis of the correlation between expression versus clinicopathological variables, including gender, age, TNM classifications, tumor size, lymph node metastasis and overall prognosis. It was shown that positive staining of CIC-3 can be present in both hepatocarcinoma and its paired normal controls; and that CIC-3 was significantly over-expressed in hepatcarcioma on the whole relative to paired normal controls. Moreover, up-regulation of CIC-3 markedly correlated with tumor size and overall prognosis, suggesting that CIC-3 expression could predict both tumor size and overall prognosis in hepatocarcinoma.     

ARL4C stabilized by AKT/mTOR pathway promotes the invasion of PTEN-deficient primary human glioblastoma

Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) deficiency in primary human glioblastoma (GBM) is associated with increased invasiveness and poor prognosis with unknown mechanisms. Therefore, how loss of PTEN promotes GBM progression remains to be elucidated. Herein, we identified that ADP-ribosylation factor like-4C (ARL4C) was highly expressed in PTEN-deficient human GBM cells and tissues. Mechanistically, loss of PTEN stabilized ARL4C protein due to AKT/mTOR pathway-mediated inhibition of ARL4C ubiquitination. Functionally, ARL4C enhanced the progression of GBM cells in vitro and in vivo. Moreover, microarray profiling and GST pull-down assay identified that ARL4C accelerated tumor progression via RAC1-mediated filopodium formation. Importantly, targeting PTEN potently inhibited GBM tumor progression in vitro and in vivo, whereas overexpression of ARL4C reversed the tumor progression impaired by PTEN overexpression. Clinically, analyses with patients' specimens validated a negative correlation between PTEN and ARL4C expression. Elevated ARL4C expression but PTEN deficiency in tumor was associated with poorer disease-free survival and overall survival of GBM patients. Taken together, ARL4C is critical for PTEN-deficient GBM progression and acts as a novel prognostic biomarker and a potential therapeutic candidate. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.     

Epidemiology of human adenovirus infection in children hospitalized with lower respiratory tract infections in Hunan,China

To investigate the current genotypes of circulating human adenovirus (HAdV) strains, we molecularly genotyped HAdV in the nasopharyngeal aspirates (NPAs) of patients with acute lower respiratory tract infections (ALRTIs) and attempted to determine their associations with clinical symptoms. A total of 4751 NPA samples were collected from 4751 patients admitted to Hunan Provincial People's Hospital from September 2007 to March 2014, of which 447 (9.4%) samples were HAdV positive. Fourteen different HAdV types were identified; HAdV types 1 to 7 (HAdV 1-7) were identified in 95.7% of the 447 NPA samples with HAdV-7 and HAdV-3 being the most prevalent. In addition, 93.3% (417 of 447) of patients were younger than 5 years. The incidence of HAdV infection peaked in summer. Different HAdV types showed a predilection for different age groups and different seasonal distribution patterns. Coinfection of HAdVs and other respiratory viruses was detected in 63.3% (283 of 447) of the HAdV-positive samples. The most common clinical diagnosis was pneumonia and the most common symptoms were fever and cough. In comparison with children infected with HAdV-3 alone, those infected with HAdV-7 alone had an increased frequency of severe pneumonia involvement (11.6% vs 32.4%; P = 0.031), higher intensive care unit admission rates (7.0% vs 26.5%; P = 0.019), and a longer length of hospital stay (P = 0.03). Mixed infections in younger children were associated with a longer hospital stay (P = 0.023). Our results demonstrate the recent changes in the trends of circulating HAdV genotypes associated with ALRTIs in Hunan China.     

Functional characterization of CEP250 variant identified in nonsyndromic retinitis pigmentosa

Retinitis pigmentosa (RP) is the most common manifestation of inherited retinal diseases with high degree of genetic, allelic, and phenotypic heterogeneity. CEP250 encodes the C‐Nap1 protein and has been associated with various retinal phenotypes. Here, we report the identification of a mutation (c.562C>T, p.R188*) in the CEP250 in a consanguineous family with nonsyndromic RP. To gain insights into the molecular pathomechanism underlying CEP250 defects and the functional relevance of CEP250 variants in humans, we conducted a functional characterization of CEP250 variant using a novel Cep250 knockin mouse line. Remarkably, the disruption of Cep250 resulted in severe impairment of retinal function and significant retinal morphological alterations. The homozygous knockin mice showed significantly reduced retinal thickness and ERG responses. This study not only broadens the spectrum of phenotypes associated with CEP250 mutations, but also, for the first time, elucidates the function of CEP250 in photoreceptors using a newly established animal model.