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11.
目的观察谷氨酰胺联合益生菌对失代偿肝硬化患者的疗效与安全性。方法收集本院失代偿肝硬化患者78例,随机分为2组,每组39例:对照组用常规治疗;在常规治疗的基础上,试验组用谷氨酰胺联合益生菌治疗,复方谷氨酰胺肠溶胶囊,每次750 mg;枯草杆菌二联活菌肠溶胶囊口服,每次250 mg,两药均每天3次,连用4周。治疗前后,测定2组的肠黏膜通透性指标、肝功能指标、疗效和药物不良反应(ADR)发生率。结果治疗后,试验组与对照组的尿乳果糖/甘露醇比值分别是0.09±0.06,0.12±0.08,这2组的血清白细胞介素-8水平分别是(15.02±3.69),(18.45±4.10)ng·L-1,这2组的血清谷丙转氨酶水平分别是(24.61±14.29),(36.82±15.67)U·L-1,上述3个指标在组间比较差异均有统计学意义(均P<0.05)。对照组和试验组的改善率分别为71.80%,92.31%,差异有统计学意义(P<0.05)。对照组和试验组的ADR发生率分别为15.38%(6例/39例),20.51%(8例/39例),组间比较差异无统计学意义(P>0.05)。结论谷氨酰胺联合益生菌对失代偿肝硬化患者的治疗效果确切,有助于降低肠黏膜通透性和提高肝功能;且不增加ADR发生率。  相似文献   
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Bridging immunoassays commonly used to detect and characterize immunogenicity during biologic development do not provide direct information on the presence or development of a memory anti-drug antibody (ADA) response. In this study, a B cell ELISPOT assay method was used to evaluate pre-existing ADA for anti-TNFR1 domain antibody, GSK1995057, an experimental biologic in treatment naive subjects. This assay utilized a 7-day activation of PBMCs by a combination of GSK1995057 (antigen) and polyclonal stimulator followed by GSK1995057-specific ELISPOT for the enumeration of memory B cells that have differentiated into antibody secreting cells (ASC) in vitro. We demonstrated that GSK1995057-specific ASC were detectable in treatment-naïve subjects with pre-existing ADA; the frequency of drug-specific ASC was low and ranged from 1 to 10 spot forming units (SFU) per million cells. Interestingly, the frequency of drug-specific ASC correlated with the ADA level measured using an in vitro ADA assay. We further confirmed that the ASC originated from CD27+ memory B cells, not from CD27?-naïve B cells. Our data demonstrated the utility of the B cell ELISPOT method in therapeutic protein immunogenicity evaluation, providing a novel way to confirm and characterize the cell population producing pre-existing ADA. This novel application of a B cell ELISPOT assay informs and characterizes immune memory activity regarding incidence and magnitude associated with a pre-existing ADA response.  相似文献   
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Cytosine base editors (CBEs) and adenine base editors (ABEs), which are generally composed of an engineered deaminase and a catalytically impaired CRISPR‐Cas9 variant, are new favorite tools for single base substitution in cells and organisms. In this review, we summarize the principle of base‐editing systems and elaborate on the evolution of different platforms of CBEs and ABEs, including their deaminase, Cas9 variants, and editing outcomes. Moreover, we highlight their applications in mouse and human cells and discuss the challenges and prospects of base editors. The ABE‐ and CBE systems have been used in gene silencing, pathogenic gene correction, and functional genetic screening. Single base editing is becoming a new promising genetic tool in biomedical research and gene therapy.  相似文献   
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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.  相似文献   
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