CD39 Produced from Human GMSCs Regulates the Balance of Osteoclasts and Osteoblasts through the Wnt/β-Catenin Pathway in Osteoporosis

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PM2.5 induced lung injury through upregulating ROS-dependent NLRP3 Inflammasome-Mediated Pyroptosis

The main cause of air pollution is PM_2.5, which directly causes lung injury through respiration. Oxidative stress and inflammation are considered to be the key mechanism of cell damage. Pyroptosis is a process of the programmed death of inflammatory cells and as a dangerous endogenous signal, it is widely involved in different inflammatory diseases. However, few studies have been conducted on PM_2.5 exposure and cell pyroptosis. In this study, we aimed to investigate the effect of PM_2.5 on apoptosis, pyroptosis and cell cycle arrest regulated by reactive oxygen species production. Balb/c mice were exposed to PM_2.5 dynamically and verified by the RAW264.7 cells in vitro. The results showed the activation of NF-κB and NLRP3 inflammasome and the release of IL-1β and reactive oxygen species were caused by exposure to PM_2.5. The maturation of IL-1β relied on Caspase-1, and the active Caspase-1 was related to cell pyroptosis. Oxidative stress, inflammation, apoptosis and pyroptosis all affected the cell cycle. This study describes a potentially important mechanism of PM_2.5-induced lung damage that PM_2.5 promotes lung injury via upregulating ROS-NLRP3-mediated the RAW264.7 cells pyroptosis.     

Has the public lost confidence in vaccines because of a vaccine scandal in China

BackgroundA vaccine manufacturer in China and regulatory authorities have been the focus of widespread outrage due to a vaccine scandal. We conducted a rapid survey during a time of intense mainstream and social media attention to determine whether the public’s confidence in vaccines was affected.MethodsWe selected 7 cities that were not involved in the scandal as the setting for the survey, which was conducted in August 2018. We used a convenience sampling strategy to select subjects in urban streets and rural villages for a face-to-face questionnaire-based survey. Subjects were asked to describe their levels of confidence on a scale from 0 to 9, in which 0 means no confidence, and 9 means very confident. Respondents were asked to assess confidence for two points in time – recollection of their level of confidence before hearing about the scandal and their level of confidence at the time of the survey.ResultsIn total, 683 individuals were invited to participate and 591 questionnaires were completed, for a response rate of 86.5%. Among respondents, 86.80% had heard of the vaccine scandal. The most common channel for hearing about the scandal was social media (e.g., WeChat), 40.6% of respondents. Regardless of gender, age, education level, province, town or country, or having children under 15 years old, respondents reported a significant decrease in confidence in domestically-produced vaccines. The mean pre-scandal confidence level recalled by respondents was 6.7, and the mean confidence level at the time of the survey was 3.2. Confidence in vaccine manufacturers, institutes for drug control, and drug supervision authorities decreased from 5.6 to 6.0 before the vaccine scandal to 2.0–3.2 at the time of the survey. Confidence in vaccine manufacturers decreased the most, from 5.6 before the scandal to 2.0; confidence in institutes for drug control decreased from 5.8 before the scandal to 2.6 at the time of the survey.ConclusionThis study demonstrated that public confidence was significantly affected by the vaccine scandal, particularly for vaccine producers and drug regulators. The decline in confidence is a reminder to governments that in order to build public confidence for vaccination, regulators have to reform regulatory practices and manufacturers have to ensure vaccine quality.     

Cellular basis of diabetic nephropathy: V. Endoglin expression levels and diabetic nephropathy risk in patients with Type 1 diabetes

Endoglin is an accessory receptor molecule that, in association with transforming growth factor β (TGF-β) family receptors Types I and II, binds TGF-β1, TGF-β3, activin A, bone morphogenetic protein (BMP)-2 and BMP-7, regulating TGF-β dependent cellular responses. Relevant to diabetic nephropathy, endoglin, expressed in vascular endothelial and smooth muscle cells, fibroblasts, and mesangial cells, negatively regulates extracellular matrix (ECM). The aim of this study was to evaluate endoglin expression in cultured skin fibroblasts from patients with Type 1 diabetes with and without diabetic nephropathy. Kidney and skin biopsies were performed in 125 Type 1 diabetic patients. The 20 with the fastest rate of mesangial expansion (estimated by electron microscopy) and proteinuria (“fast-track”) and the 20 with the slowest rate and normoalbuminuria (“slow-track”), along with 20 controls were studied. Endoglin mRNA expression was assessed by microarray and quantitative real-time polymerase chain reaction (QRT-PCR) and protein expression by Western blot. Age and sex distribution were similar among groups. Diabetes duration was similar (20±8 vs. 24±7 years), hemoglobin A1c lower (8.4±1.2% vs. 9.4±1.5%), and glomerular filtration rate higher (115±13 vs. 72±20 ml/min per 1.73 m²) in slow-track vs. fast-track patients. Microarray endoglin mRNA expression levels were higher in slow-track (1516.0±349.9) than fast-track (1211.0±274.9; P=.008) patients or controls (1223.1±422.9; P=.018). This was confirmed by QRT-PCR. Endoglin protein expression levels correlated with microarray (r=0.59; P=.044) and QRT-PCR (r=0.61; P=.034) endoglin mRNA expression. These studies are compatible with the hypothesis that slow-track Type 1 diabetic patients, strongly protected from diabetic nephropathy, have distinct cellular behaviors that may be associated with reduced ECM production.     

长QT综合征(一)

长QT综合征(LQTS)是一种心律紊乱疾病,表现为QT间期延长和T波异常,与尖端扭转型室性心动过速(TdP)的易感性增加相关,可导致晕厥、心脏骤停甚至猝死等心脏事件。先天性LQTS的发生率约为1/2 500,由编码或调节心脏钠、钾和钙离子通道的基因突变引起。至今已发现14个亚型,其中12个引起Romano-Ward综合征,2个引起伴耳聋的Jervell and Lange-Nielsen综合征,总共有1 200多个突变。大部分已知的基因突变在编码钾离子通道的基因上。疾病的严重程度受基因突变类型、突变位点和离子通道的生物物理特性影响。临床LQTS相关的症状与年龄、性别和QT间期延长程度相关。心脏事件的发生率在青少年和年轻的成年人中最高。女性比男性问题更多。QT间期越长,心脏事件发生率越高。在已知基因型的个体中,LQT1~3占90%~95%。在LQT1~3和LQT7个体存在基因特异性的心电图(ECG)表现。心脏事件的触发因素也因基因型的不同而不同。认识到基因特异的临床特征和ECG模式之间的关系可提高诊断的精确性。家族筛查、系列ECG跟踪随访、运动试验等不仅对先证者的诊断很重要,对于其他受累家族成员的确认也很重要。在所有亚型中,β阻滞剂对LQT1型患者最有效。左心交感神经切除术(LCSD)可增加心室颤动阈值从而显示可降低心脏事件的发生率。微创的LCSD术式比传统的方法更安全,患者恢复更快。植入式心脏复律除颤器(ICD)可对致命性心律失常提供最好的保护,但有必要使用ICD的危险分层,因为有50%的LQTS患者会终身无心脏事件发生。获得性LQTS在普通人群更常见,女性对延长QT间期的药物和电解质紊乱引起的TdP更易感。去除诱因是矫正获得性LQTS的最好办法。避免延长QT间期的药物和基因特异性的触发因素也能降低遗传性LQTS的心脏事件发生率。     

吡柔比星与表柔比星在乳腺癌新辅助化疗中的成本-效果分析

目的:比较吡柔比星与表柔比星在乳腺癌新辅助化疗中的成本-效果。方法:将188例乳腺癌新辅助化疗患者按治疗方案的不同分为CTF组(91例)与CEF组(97例)。CTF组术前经吡柔比星+环磷酰胺+氟尿嘧啶辅助化疗;CEF组术前经表柔比星+环磷酰胺+氟尿嘧啶辅助化疗,2组均进行4个周期。治疗后运用药物经济学原理进行成本-效果分析。结果:2组治疗总有效率为86.8%和90.7%,差异无统计学意义(P>0.05);2组均出现不同程度的不良反应,但差异无显著性(P>0.05)。CTF与CEF组的成本-效果比分别为198.59和248.73,2组比较差异有统计学意义(P<0.05)。结论:吡柔比星新辅助化疗方案治疗乳腺癌与表柔比星方案疗效相当,但更为经济。     

Dose and Hg species determine the T-helper cell activation in murine autoimmunity

Inorganic mercury (mercuric chloride--HgCl(2)) induces in mice an autoimmune syndrome (HgIA) with T cell-dependent polyclonal B cell activation and hypergammaglobulinemia, dose- and H-2-dependent production of autoantibodies targeting the 34 kDa nucleolar protein fibrillarin (AFA), and systemic immune-complex deposits. The organic mercury species methylmercury (MeHg) and ethylmercury (EtHg--in the form of thimerosal) induce AFA, while the other manifestations of HgIA seen after treatment with HgCl(2) are present to varying extent. Since these organic Hg species are converted to the autoimmunogen Hg(2+) in the body, their primary autoimmunogen potential is uncertain and the subject of this study. A moderate dose of HgCl(2) (8 mg/L drinking water--internal dose 148 micro gHg/kg body weight [bw]/day) caused the fastest AFA response, while the induction was delayed after higher (25 mg/L) and lower (1.5 and 3 mg/L) doses. The lowest dose of HgCl(2) inducing AFA was 1.5 mg/L drinking water which corresponded to a renal Hg(2+) concentration of 0.53 micro g/g. Using a dose of 8 mg HgCl(2)/L this threshold concentration was reached within 24 h, and a consistent AFA response developed after 8-10 days. The time lag for the immunological part of the reaction leading to a consistent AFA response was therefore 7-9 days. A dose of thimerosal close to the threshold dose for induction of AFA (2 mg/L drinking water--internal dose 118 micro gHg/kg bw per day), caused a renal Hg(2+) concentration of 1.8 micro g/g. The autoimmunogen effect of EtHg might therefore be entirely due to Hg(2+) formed from EtHg in the body. The effect of organic and inorganic Hg species on T-helper type 1 and type 2 cells during induction of AFA was assessed as the presence and titre of AFA of the IgG1 and IgG2a isotype, respectively. EtHg induced a persistent Th1-skewed response irrespectively of the dose and time used. A low daily dose of HgCl(2) (1.5-3 mg/L) caused a Th1-skewed AFA response, while a moderate dose (8 mg/L) after 2 weeks resulted in a balanced or even Th2-skewed response. Higher daily doses of HgCl(2) (25 mg/L) caused a balanced Th2-Th1 response already from onset. In conclusion, while metabolically formed Hg(2+) might be the main AFA-inducing factor also after treatment with EtHg, the quality of the Hg-induced AFA response is modified by the species of Hg as well as the dose.     

Exosomes in ascites from patients with human pancreatic cancer enhance remote metastasis partially through endothelial-mesenchymal transition

BackgroundDespite advances in multidisciplinary treatment, the prognosis of pancreatic cancer remains poor. Since distant metastasis defines prognosis, elucidation of the mechanism of metastasis is important for improving survival. Exosomes are extracellular secretory vesicles and are responsible for intercellular communication. In this study, we investigated whether exosomes secreted by human pancreatic cancer cells are involved in promoting distant metastasis of cancer and the mechanism that underlies the promotion of metastasis.MethodsExosomes were isolated from ascites of a patient with pancreatic cancer and a patient with liver cirrhosis as a control. Three days after the administration of exosomes to nude mice, GFP-labeled human pancreatic cancer cells were injected via the spleen or tail vein, and then the liver and lungs were histologically analyzed. To elucidate the mechanism, vascular permeability was estimated using FITC-dextran in place of pancreatic cancer cells in vivo and human umbilical vascular endothelial cells (HUVECs) were used to analyze vascular permeability and the induction of endothelial-mesenchymal transition (EndMT) in vitro.ResultsDistant metastasis and vascular permeability were significantly enhanced in mice treated with exosomes from pancreatic cancer patients in comparison to exosomes from a control patient in vivo. In addition, exosomes from pancreatic cancer patients significantly enhanced vascular permeability and the induction of EndMT in HUVECs in vitro.ConclusionExosomes derived from pancreatic cancer cells form a pre-metastatic niche and promote the extravasation and colonization of pancreatic cancer cells to remote organs, partially through endothelial-mesenchymal transition.