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991.
992.
MicroRNA-155 (miR155) has been demonstrated as a central regulator of immune responses induced by inflammatory mediators. Previous studies suggest that miR155 may play adverse effects in various diseases. We hereby explored the roles of miR155 in the pathogenesis of Guillain–Barré syndrome (GBS). Peripheral blood mononuclear cells (PBMCs) were separated from GBS patients and healthy controls. Expression of miR155 in PBMCs was detected by quantitative PCR. An inhibitor of miR155 was transfected into the cultured PBMCs and the GBS-related cytokines were detected. Significantly, our study demonstrated that miR155 was downregulated in PBMCs from GBS patients and silencing of miR155 profoundly promoted the production of Th1-type cytokines in vitro. Our data effectively demonstrate a protective role of miR155 in GBS, which suggests that miR155 may be a promising target for the therapy of the disease.  相似文献   
993.
目的:观察巢蛋白在成年大鼠室周器官细胞的表达,并根据巢蛋白阳性表达细胞的位置、大小及形态特点进行分类.方法:成年SD雄性大鼠,经心灌注后,用免疫组织化学检测巢蛋白在室周器官细胞的表达.结果:在正中隆起(64.32%±8.55%)、穹隆下器(15.76%±2.16%)、连合下器(40.15%±6.16%)和最后区(28.85%±4.53%)都可见大量的巢蛋白阳性表达细胞.根据细胞所在位置、大小和形态将其分为5类.Ⅰ类是室管膜细胞,部分室管膜细胞有长10~180 μm的胞突;Ⅱ类细胞较小,细胞及细胞核呈圆形或卵圆形,有1~2个纤细长达20~30 μm的胞突;Ⅲ类细胞胞体较Ⅱ类大,细胞及细胞核不规则,胞质浅染,无胞突;Ⅳ类细胞及细胞核呈圆形或卵圆形,大部分细胞无胞突,部分细胞有长4~15 μm的胞突;Ⅴ类细胞胞体较大,细胞及细胞核呈圆形或卵圆形,有1~3个粗长的突起,并可见2~3级分支,胞突长50~100μm.结论:成年大鼠室周器官有大量巢蛋白阳性表达细胞,有的是具有增殖和分化潜能的神经干细胞/祖细胞,有的是巢蛋白阳性表达的神经元.  相似文献   
994.
995.
ObjectivesUndetectable or low-level hepatitis B virus (HBV) DNA and drug resistance mutations in patients may increase the risk of HBV transmission or cause active viral replication and other clinical problems. Here, we established a highly sensitive and practical method for HBV and drug resistance detection using a polymerase chain reaction (PCR) -based CRISPR-Cas13a detection system (referred to as PCR-CRISPR) and evaluated its detection capability using clinical samples.MethodsSpecific CRISPR RNAs (crRNAs) are designed for HBV DNA detection and YMDD (tyrosine-methionine-aspartate-aspartate) variant identification. The HBV DNA was detected in 312 serum samples for HBV diagnosis using quantification PCR (qPCR) and PCR-CRISPR. Additionally, 424 serum samples for YMDD testing were detected by qPCR, direct sequencing, and our assay.ResultsUsing PCR-CRISPR, one copy per test of HBV DNA was detected with HBV-1 crRNA in 15 min after PCR amplification. Consistent results with qPCR were observed for 302 samples, while the remaining 10 samples with low-level HBV DNA were detectable by PCR-CRISPR and droplet digital PCR but not by qPCR. PCR-CRISPR diagnosed all 412 drug-resistant samples detected by the YMDD detection qPCR kit and direct sequencing, as well as the other 12 drug-resistant samples with low-level HBV DNA undetectable by qPCR and direct sequencing.ConclusionsWe developed a novel PCR-CRISPR method for highly sensitive and specific detection of HBV DNA and drug resistance mutations. One copy per test for HBV DNA and YMDD drug resistance mutations could be detected. This method has wide application prospects for the early detection of HBV infection, drug resistance monitoring and treatment guidance.  相似文献   
996.
Vγ9Vδ2 T cells are promising candidates for cellular tumor immunotherapy. Due to their HLA-independent mode of action, allogeneic Vγ9Vδ2 T cells can be considered for clinical application. To apply allogeneic Vγ9Vδ2 T cells in adoptive immunotherapy, the methodology used to obtain adequate cell numbers with optimal effector function in vitro needs to be optimized, and clinical safety and efficacy also need to be proven. Therefore, we developed a novel formula to improve the expansion of peripheral γδ T cells from healthy donors. Then, we used a humanized mouse model to validate the therapeutic efficacy of expanded γδ T cells in vivo; furthermore, the expanded γδ T cells were adoptively transferred into late-stage liver and lung cancer patients. We found that the expanded cells possessed significantly improved immune effector functions, including proliferation, differentiation, and cancer cell killing, both in vitro and in the humanized mouse model. Furthermore, a phase I clinical trial in 132 late-stage cancer patients with a total of 414 cell infusions unequivocally validated the clinical safety of allogeneic Vγ9Vδ2 T cells. Among these 132 patients, 8 liver cancer patients and 10 lung cancer patients who received ≥5 cell infusions showed greatly prolonged survival, which preliminarily verified the efficacy of allogeneic Vγ9Vδ2 T-cell therapy. Our clinical studies underscore the safety and efficacy of allogeneic Vγ9Vδ2 T-cell immunotherapy, which will inspire further clinical investigations and eventually benefit cancer patients.  相似文献   
997.
BackgroundTrichinella spiralis is a kind of intestinal nematode that can strongly modulate the host immune system. However, the effects of T. spiralis infection on the intestinal flora are poorly understood. This study aimed to explore the effect of T. spiralis infection on the intestinal flora.MethodsThe intestinal contents of T. spiralis infected mice were examined through high-throughput sequencing (Illumina) of the V3–V4 hypervariable region in bacterial 16S rRNA gene. The sequences were analyzed using the QIIME software package and other bioinformatics methods.ResultsAltogether 2,899,062 sequences were generated from the samples collected from different intestinal regions at various infection time points; the 44,843 Operational Taxonomic Unit (OTUs) analysis showed that T. spiralis infection would decrease the diversity of intestinal flora in the infected mice relative to that in the uninfected ones, especially in the large intestine and feces. Further analysis indicated that, the genera Oscillospira from the phylum Firmicutes showed a higher abundance in the helminth-infected small and larger intestines; the genera Bacteroides from the phyla Bacteroides, the genera Lactobacillus from the phyla Firmicutes, the genera Escherichia from the phyla Proteobacteria, and the genera Akkermansia from the phyla Verrucomicrobia displayed increased abundances in the T. spiralis positive fecal samples compared with those in the negative samples.ConclusionsT. spiralis infection decreases the diversity of the intestinal flora in the infected mouse. However, it remains unclear about the association between the changes in intestinal flora caused by T. spiralis infection and the parasite pathogenesis, which should be further examined.  相似文献   
998.
Objective:To develop and evaluate a practical automatic treatment planning method for intensity-modulated radiation therapy (IMRT) in cervical cancer cases.Methods:A novel algorithm named as Optimization Objectives Tree Search Algorithm (OOTSA) was proposed to emulate the planning optimization process and achieve a progressively improving IMRT plan, based on the Eclipse Scripting Application Programming Interface (ESAPI). 30 previously treated cervical cancer cases were selected from the clinical database and comparison was made between the OOTSA-generated plans and clinical treated plans and RapidPlan-based (RP) plans.Results:In clinical evaluation, compared with plan scores of the clinical plans and the RP plans, 22 and 26 of the OOTSA plans were considered as clinically improved in terms of plan quality, respectively. The average conformity index (CI) for the PTV in the OOTSA plans was 0.86 ± 0.01 (mean ± 1 standard deviation), better than those in the RP plans (0.83 ± 0.02) and the clinical plans (0.71 ± 0.11). Compared with the clinical plans, the mean doses of femoral head, rectum, spinal cord and right kidney in the OOTSA plans were reduced by 2.34 ± 2.87 Gy, 1.67 ± 2.10 Gy, 4.12 ± 6.44 Gy and 1.15 ± 2.67 Gy. Compared with the RP plans, the mean doses of femoral head, spinal cord, right kidney and small intestine in the OOTSA plans were reduced by 3.31 ± 1.55 Gy, 4.25 ± 3.69 Gy, 1.54 ± 2.23 Gy and 3.33 ± 1.91 Gy, respectively. In the OOTSA plans, the mean dose of bladder was slightly increased, with 2.33 ± 2.55 Gy (versus clinical plans) and 1.37 ± 1.74 Gy (vs RP plans). The average elapsed time of OOTSA and clinical planning were 59.2 ± 3.47 min and 76.53 ± 5.19 min.Conclusion:The plans created by OOTSA have been shown marginally better than the manual plans, especially in preserving OARs. In addition, the time of automatic treatment planning has shown a reduction compared to a manual planning process, and the variation of plan quality was greatly reduced. Although improvement on the algorithm is warranted, this proof-of-concept study has demonstrated that the proposed approach can be a practical solution for automatic planning.Advances in knowledge:The proposed method is novel in the emulation strategy of the physicists’ iterative operation during the planning process. Based on the existing optimizers, this method can be a simple yet effective solution for automated IMRT treatment planning.  相似文献   
999.
Liu  Jinding  Hao  Ting  Cheng  Xiaojuan  Wang  Jiaqi  Li  Wenyan  Liu  Zidong  Shi  Jie  Li  Zeqin  Ren  Jianbo  Yun  Keming  Zhang  Gengqian 《International journal of legal medicine》2021,135(1):13-21
International Journal of Legal Medicine - The identification of a suspect in a degraded and unbalanced DNA mixture has been a challenge for the standard short tandem repeat polymorphisms (STR)...  相似文献   
1000.
International Journal of Legal Medicine - Genotypes of 42 Y chromosome STR (Y-STR) loci were analyzed for a sample of 1420 unrelated males and 1160 father-son pairs from a Chinese Han population....  相似文献   
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