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91.
Recent experimental strategies to reduce graft-versus-host disease (GVHD) have focused largely on modifying innate immunity. Toll-like receptor (TLR)-driven myeloid differentiation primary response 88 (MyD88)-dependent signalling pathways that initiate adaptive immune function are also critical for the pathogenesis of GVHD. This study aimed to delineate the role of host MyD88 in the development of acute GVHD following fully major histocompatibility complex-mismatched allogeneic bone marrow transplantation (BMT). When myeloablated BALB/c MyD88 knock-out recipients were transplanted with C57BL/6 (B6) donor cells, they developed significantly more severe GVHD than wild-type (WT) BALB/c hosts. The increased morbidity and mortality in MyD88–/– mice correlated with increased serum levels of lipopolysaccharide and elevated inflammatory cytokines in GVHD target organs. Additionally, MyD88 deficiency in BMT recipients led to increased donor T cell expansion and more donor CD11c+ cell intestinal infiltration with apoptotic cells but reduced proliferation of intestinal epithelial cells compared with that in WT BMT recipients. Decreased expression of tight junction mRNA in epithelial cells of MyD88–/– mice suggested that MyD88 contributes to intestinal integrity. Cox-2 expression in the GVHD-targeted organs of WT mice is increased upon GVHD induction, but this enhanced expression was obviously inhibited by MyD88 deficiency. The present findings demonstrate an unexpected role for host MyD88 in preventing GVHD after allogeneic BMT.  相似文献   
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吴洋  宋燕妮 《现代肿瘤医学》2020,(18):3255-3259
乳腺癌是一类具有异质性的肿瘤,不同患者的治疗方法和疗效都不相同。尽管目前仍在努力为激素受体(hormone receptor,HR)阳性(+)、人表皮生长因子受体2(human epidermal growth factor receptor 2,HER-2)阴性(-)、淋巴结(axillary lymph node,ALN)阴性(-)的早期乳腺癌患者寻找合适的治疗方法,但其术后是否需要化疗仍然是肿瘤科医生面临的一个难题。以往治疗主要依赖于经典的组织病理学和免疫组织化学技术,随着精准医疗时代的到来,我们需要更定量的诊断方法和合理的个体化治疗。虽然化疗可降低疾病复发风险并提高生存率,但它带来的不良反应事件会降低患者的生活质量,尤其低复发风险(recurrence risk,RS)有可能超过化疗益处。21基因检测不仅可以预测这类早期乳腺癌化疗疗效及评估预后,还可提供精准的个体化治疗方案指导用药,为患者增添信心。本文就乳腺癌21基因检测的研究进展进行综述。  相似文献   
94.
Cyclin‐dependent kinase 12 (CDK12), one of the key factors associated with DNA damage response pathways, is located on chromosome 17 proximal to Erb‐B2 receptor tyrosine kinase 2 (ERBB2). In this report, CDK12 and ERBB2 coamplification was detected by targeted next‐generation sequencing in two urothelial carcinomas. The staining intensity of the CDK12 and human epidermal growth factor receptor‐2 proteins was associated with the prognosis of each urothelial carcinoma case. Our results suggest that CDK12 coamplification with ERBB2 might be associated with tumor aggressiveness and contribution to cancer pathogenesis. Therapies targeting CDK12 should be developed for these patients.  相似文献   
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《Vaccine》2020,38(39):6141-6152
Influenza vaccination is considered the most valuable means to prevent and control seasonal influenza infections, which causes various clinical symptoms, ranging from mild cough and fever to even death. Among various influenza vaccine types, the inactivated subunit type is known to provide improved safety with reduced reactogenicity. However, there are some drawbacks associated with inactivated subunit type vaccines, with the main ones being its low immunogenicity and the induction of Th2-biased immune responses. In this study, we investigated the role of a single-stranded RNA (ssRNA) derived from the intergenic region in the internal ribosome entry site of the Cricket paralysis virus as an adjuvant rather than the universal vaccine for a seasonal inactivated subunit influenza vaccine. The ssRNA adjuvant stimulated not only well-balanced cellular (indicated by IgG2a, IFN-γ, IL-2, and TNF-α) and humoral (indicated by IgG1 and IL-4) immune responses but also a mucosal immune response (indicated by IgA), a key protector against respiratory virus infections. It also increases the HI titer, the surrogate marker of influenza vaccine efficacy. Furthermore, ssRNA adjuvant confers cross-protective immune responses against heterologous influenza virus infection while promoting enhanced viral clearance. Moreover, ssRNA adjuvant increases the number of memory CD4+ and CD8+ T cells, which can be expected to induce long-term immune responses. Therefore, this ssRNA-adjuvanted seasonal inactivated subunit influenza vaccine might be the best influenza vaccine generating robust humoral and cellular immune responses and conferring cross-protective and long-term immunity.  相似文献   
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目的探讨先天性肾性尿崩症的临床特点、基因诊断及治疗。方法回顾分析2例先天性肾性尿崩症患儿的临床资料。结果 2例男性患儿分别为5岁和3岁2个月,均以多饮多尿、生长迟缓为主要表现。经禁水-加压素试验证实为持续低比重尿。尿崩症相关基因检测发现,例1患儿精氨酸加压素受体2(AVPR2)基因外显子2杂合错义突变c.650CT(p.P217L),且为新发变异。例2患儿AVPR2基因外显子1及外显子2缺失,亦为新发变异,其母亲为携带者,父亲AVPR2基因未见异常变异。对新发的变异位点通过Mutation-taster及Polyphen2软件预测为致病性变异。2例患儿口服氢氯噻嗪联合吲哚美辛治疗1年,尿量及夜尿减少,无电解质紊乱及肾功能受损等。结论 AVPR2基因为先天性肾性尿崩症的主要致病基因,发现2种国内外未见报道的新变异位点。  相似文献   
99.
目的探讨先天性中枢性低通气综合征(CCHS)的临床和基因变异特征。方法分析1例首发表现为不明原因肺动脉高压的CCHS患儿的临床资料,并总结国内外文献中CCHS病例的临床特点、致病机制和基因变异情况。结果11月龄女婴,主要表现为浮肿、尿少、低血压、嗜睡、发绀、抽搐及颅内压增高。B型脑利钠肽、丙氨酸氨基转移酶升高,凝血酶原时间延长。颅脑磁共振示右侧额叶出血;超声心动图示中重度肺动脉高压。靶向捕获二代测序未发现可能的致病基因。采用Sanger法验证示患儿PHOX 2 B基因第3外显子存在多聚丙氨酸重复扩展变异,基因型为20/25。患儿入院后采用无创通气,睡眠时呼吸浅慢、微弱,伴血氧下降;血气分析提示二氧化碳潴留。随后改用夜间无创通气、降肺压药物治疗。复查肺动脉压力明显下降,生命体征稳定。随访至24月龄,夜间只需较低压力水平的无创通气,生长发育无异常。结论对于不明原因的肺动脉高压伴撤机困难患儿,需警惕CCHS。疑诊者应尽早针对CCHS相关基因进行靶向捕获二代测序及PHOX 2 B基因Sanger法验证。早期给予无创通气有望改善预后。  相似文献   
100.
BackgroundDetails of perioperative outcomes and survival after gastric cancer surgery in prior transplant recipients have received minimal research attention.MethodsWe performed an observational cohort study using the database of 20,147 gastric cancer patients who underwent gastrectomy at a single gastric cancer center in Korea. Forty-one solid organ recipients [kidney (n = 35), liver (n = 5), or heart (n = 1)] were matched with 205 controls using propensity score matching.ResultsOperation time, blood loss, and postoperative pain were similar between groups. Short-term complication rates were similar between transplantation and control groups (22.0% vs. 20.1%, P = 0.777). Transplantation group patients with stage 1 gastric cancer experienced no recurrence, while those with stage 2/3 cancer had significantly higher recurrence risk compared to the controls (P = 0.049). For patients with stage 1 cancer, the transplantation group had a significantly higher rate of non-gastric cancer-related deaths compared to the controls (19.2% vs. 1.4%, P = 0.001). For those with stage 2/3 cancer, significantly lower proportion of the transplantation group received adjuvant chemotherapy compared to the control group (26.7% vs. 80.3%, P < 0.001). The transplantation group had a higher (albeit not statistically significant) rate of gastric cancer-related deaths compared to the controls (40.0% vs. 18.0%, P = 0.087).ConclusionTransplant recipients and non-transplant recipients exhibited similar perioperative and short-term outcomes after gastric cancer surgery. From long-term outcome analyses, we suggest active surveillance for non-gastric cancer-related deaths in patients with early gastric cancer, as well as strict oncologic care in patients with advanced cancer, as effective strategies for transplant recipients.  相似文献   
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