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81.
《Vaccine》2022,40(11):1594-1605
In addition to providing pathogen-specific immunity, vaccines can also confer nonspecific effects (NSEs) on mortality and morbidity unrelated to the targeted disease. Immunisation with live vaccines, such as the BCG vaccine, has generally been associated with significantly reduced all-cause infant mortality. In contrast, some inactivated vaccines, such as the diphtheria, tetanus, whole-cell pertussis (DTPw) vaccine, have been controversially associated with increased all-cause mortality especially in female infants in high-mortality settings. The NSEs associated with BCG have been attributed, in part, to the induction of trained immunity, an epigenetic and metabolic reprograming of innate immune cells, increasing their responsiveness to subsequent microbial encounters. Whether non-live vaccines such as DTPw induce trained immunity is currently poorly understood. Here, we report that immunisation of mice with DTPw induced a unique program of trained immunity in comparison to BCG immunised mice. Altered monocyte and DC cytokine responses were evident in DTPw immunised mice even months after vaccination. Furthermore, splenic cDCs from DTPw immunised mice had altered chromatin accessibility at loci involved in immunity and metabolism, suggesting that these changes were epigenetically mediated. Interestingly, changing the order in which the BCG and DTPw vaccines were co-administered to mice altered subsequent trained immune responses. Given these differences in trained immunity, we also assessed whether administration of these vaccines altered susceptibility to sepsis in two different mouse models. Immunisation with either BCG or a DTPw-containing vaccine prior to the induction of sepsis did not significantly alter survival. Further studies are now needed to more fully investigate the potential consequences of DTPw induced trained immunity in different contexts and to assess whether other non-live vaccines also induce similar changes.  相似文献   
82.
《Journal of endodontics》2020,46(9):1317-1322
IntroductionThe purpose of this study is to evaluate the amount of residual obturation material of retroinstrumented surgically resected roots using controlled memory files and to evaluate the incidence of adverse treatment outcomes.MethodsThirty maxillary anterior teeth in human cadavers were selected, and nonsurgical root canal treatment was performed on these teeth. A standardized 4-mm osteotomy and a 3-mm root resection with as close to 0° bevel as possible were made on each tooth. A microsurgical diamond tip was used to create a 1- to 2-mm starting point for each retropreparation. A 25/06 and 30/06 VTaper 2H were bent at about 90° angle to mimic the clinical and anatomic restrictions and used to create a retropreparation to a depth of 14 mm. Micro–computed tomography scans were taken and analyzed for volume and percentage of residual obturation material at 5 and 10 mm. In addition, the incidences of instrument separation and crack and ledge formation in the teeth were recorded.ResultsThe median volume of residual obturation at 5 and 10 mm was 0.18 mm3 (interquartile range, 0.36 mm3) and 1.97 mm3 (interquartile range, 1.99 mm3), respectively. The overall incidence of file separation during retropreparation was 13.33% (4/30). Among the cases analyzed with micro–computed tomography, none showed crack or ledge formation.ConclusionsRetroinstrumentation of surgically resected roots using controlled memory files cleans the canal effectively with relatively low adverse treatment outcomes. Although this novel technique is limited in application, it is a safe and effective way to achieve a deep, clean retropreparation.  相似文献   
83.
Lifetime red cell concentrate (RCC) transfusions still account for significant iron overload‐related morbidity and mortality despite chelation therapy in thalassaemia. The cumulative risk of transfusion‐transmitted infections is substantial for thalassaemia patients. Pathogen reduction technologies for RCC may imply a proactive approach against new/re‐emerging pathogens and may be an ultimate safeguard for transfusion safety in the developing countries. Red cell alloimmunization may become a significant clinical challenge in thalassaemia. The availability of high‐throughput molecular blood group antigen typing in the donors may allow perfect match transfusion, beyond ABO‐D and CEK antigen‐matched transfusions. Allogeneic stem cell transplantation (A‐SCT) is the only available curative therapy in thalassaemia, but carries a substantial risk of serious adverse events and mortality. Gene addition therapy for correction of the α‐globin chain imbalance overcomes the problems of donor availability and immunological complications of A‐SCT. Gene editing by either gene disruption or correction emerged as a potential alternative to gene addition therapy in beta‐thalassaemia. A new era of novel therapeutics targeting α/β imbalance, ineffective erythropoiesis or iron dysregulation is unfolding in thalassaemia management, and a number of those now have agents in preclinical and clinical development. Hydroxyurea (HU) may improve globin chain imbalance and be beneficial for reducing or omitting transfusion requirement. Ruxolitinib has allowed steady decrease in spleen volume that may serve for avoiding splenectomy in beta‐thalassaemia. Luspatercept may restore normal erythroid differentiation and improve anaemia. Hepcidin mimetics or TMPRSS6 inhibitors may modulate ineffective erythropoiesis by iron restriction and improve anaemia and organ iron loading.  相似文献   
84.
Interstitial cystitis/bladder pain syndrome (IC/BPS) and vulvodynia are chronic pain syndromes that appear to be intertwined from the perspectives of embryology, pathology and epidemiology. These associations may account for similar responses to various therapies.  相似文献   
85.
86.
Aims: Relapse rates among cigarette smokers are high. Few studies have examined time-to-relapse using survival analysis in racially/ethnically diverse smokers and initial abstinence criteria have been inconsistent or unspecified. This study compared survival curves using two common definitions of initial abstinence. We hypothesized greater relapse rates among participants abstinent for only 24 hours (h) at the end-of-therapy (EOT) compared with 7 days. Methods: Adult smokers (59% Black, 22% Hispanic and 17% White) received 8-sessions of group cognitive behavioural therapy (CBT) plus transdermal nicotine patches and were assessed monthly up to 12 months post-EOT. Participants reporting abstinence (7-day point prevalence abstinence [ppa] or 24-h ppa) at the EOT were included in Kaplan–Meier curves. Results: Of 301 participants, 120 (40%) reported 7-day ppa at the EOT and an additional 29 (10%) reported 24-h ppa only. Over the 12-month follow-up period, nearly 50% remained abstinent. Of those who resumed smoking, most relapses occurred within the first three months. Survival curves indicated that median survival was 207 and 225 days for 7-day and 24-h definitions of abstinence, respectively. The difference in time-to-relapse between participants abstinent for 24?h at the EOT versus 7-days was not significant (p?=?0.14). Conclusions: Operationalization of initial abstinence is important for relapse analyses and comparisons of survival curves across samples. Participants reported high rates of abstinence and relapse rates were relatively low. Contrary to expectations, 24-h ppa at the EOT was not associated with greater relapse than 7-day abstinence. This suggests either measure may be utilized in relapse prevention research in racially/ethnically diverse treatment-seekers.  相似文献   
87.
88.
我国属胃癌高发国家,且以进展期胃癌为主。以手术和化疗为主的多学科治疗无法有效改善晚期胃癌患者的预后。近年来,免疫检查点抑制剂类药物的疗效在诸多癌症中得到了证实,因此,该类药物在胃癌中的治疗效果也受到了广泛的关注。本文对近年来的相关研究成果进行综述,全面介绍了免疫检查点抑制剂类药物在胃癌治疗中的临床应用情况、联合用药情况以及不良反应。对于其他治疗均失败的晚期胃癌患者,PD-1抑制剂是一个可行的治疗选项,其代表药物派姆单抗是目前唯一被美国食品药品监督管理局批准应用于胃癌治疗的免疫抑制剂类药物,而我国国家食品药品监督管理总局尚未批准任何此类药物应用于胃癌的临床治疗。如何进一步提高治疗的客观缓解率,将会是后续临床和基础研究的一大焦点。  相似文献   
89.
PurposeTo compare morphological imaging features and CT texture histogram parameters between grade 3 pancreatic neuroendocrine tumors (G3-NET) and neuroendocrine carcinomas (NEC).Materials and methodsPatients with pathologically proven G3-NET and NEC, according to the 2017 World Health Organization classification who had CT and MRI examinations between 2006-2017 were retrospectively included. CT and MRI examinations were reviewed by two radiologists in consensus and analyzed with respect to tumor size, enhancement patterns, hemorrhagic content, liver metastases and lymphadenopathies. Texture histogram analysis of tumors was performed on arterial and portal phase CT images. images. Morphological imaging features and CT texture histogram parameters of G3-NETs and NECs were compared.ResultsThirty-seven patients (21 men, 16 women; mean age, 56 ± 13 [SD] years [range: 28-82 years]) with 37 tumors (mean diameter, 60 ± 46 [SD] mm) were included (CT available for all, MRI for 16/37, 43%). Twenty-three patients (23/37; 62%) had NEC and 14 patients (14/37; 38%) had G3-NET. NECs were larger than G3-NETs (mean, 70 ± 51 [SD] mm [range: 18 - 196 mm] vs. 42 ± 24 [SD] mm [range: 8 - 94 mm], respectively; P = 0.039), with more tumor necrosis (75% vs. 33%, respectively; P = 0.030) and lower attenuation on precontrast (30 ± 4 [SD] HU [range: 25-39 HU] vs. 37 ± 6 [SD] [range: 25-45 HU], respectively; P = 0.002) and on portal venous phase CT images (75 ± 18 [SD] HU [range: 43 - 108 HU] vs. 92 ± 19 [SD] HU [range: 46 - 117 HU], respectively; P = 0.014). Hemorrhagic content on MRI was only observed in NEC (P = 0.007). The mean ADC value was lower in NEC ([1.1 ± 0.1 (SD)] × 10−3 mm2/s [range: (0.91 - 1.3) × 10−3 mm2/s] vs. [1.4 ± 0.2 (SD)] × 10−3 mm2/s [range: (1.1 - 1.6) × 10−3 mm2/s]; P = 0.005). CT histogram analysis showed that NEC were more heterogeneous on portal venous phase images (Entropy-0: 4.7 ± 0.2 [SD] [range: 4.2-5.1] vs. 4.5 ± 0.4 [SD] [range: 3.7-4.9]; P = 0.023).ConclusionPancreatic NECs are larger, more frequently hypoattenuating and more heterogeneous with hemorrhagic content than G3-NET on CT and MRI.  相似文献   
90.
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