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《Vaccine》2022,40(31):4105-4115
The etiologic agents of visceral leishmaniasis are Leishmania infantum and Leishmania donovani. Despite the variety of drugs available to treat leishmaniasis, most lead to serious adverse effects, and resistance to these drugs has been reported. Currently, no leishmaniasis vaccine is available for humans. That is why the group developed transgenic L. infantum promastigote lines, which express toxic proteins after differentiation into amastigotes. That is why group developed the pFL-AMA plasmid and transfected it into L. Infantum promastigotes. This plasmid was expressed only in the amastigote form of the parasite. Sequences encoding toxic proteins (active bovine trypsin and egg avidin) were inserted in this plasmid, and the transfected parasites died after the differentiation process. In this study, two immunization protocols were performed in BALB/c mice: prime and prime-boost immunization prior to challenge with the wild-type L. infantum (WT). The parasite burdens in the spleen, liver, and bone marrow were evaluated to verify immunological protection. Histopathological analysis of the spleen and liver and the humoral immune response were also performed. The data showed that the parasite burden was reduced in prime-boosted mice in the spleen, liver, and bone marrow, indicating that mice immunized with two doses of the transfected parasites were satisfactorily protected. High levels of IgG, IgG1, and IgG2a antibodies were observed, as well as the presence of anti-inflammatory cytokine Interleukine-10 and pro-inflammatory cytokine Tumor Necrosis Factor-α (TNF-α) and Interferon-γ (IFN – γ) suggesting a Th1/Th2 mix response, in addition to the presence of multinucleated giant cells in the spleen and lymphocyte infiltration in the liver. Therefore, L. infantum transfected with a toxic plasmid is an excellent vaccine candidate against visceral leishmaniasis and the application of a boost before the challenge promotes greater protection against WT L. infantum infection.  相似文献   
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目的 探讨右美托咪定联合综合体温保护对腔镜手术治疗老年恶性肿瘤患者苏醒期质量及免疫功能的影响。方法 选择择期行腔镜手术治疗的老年恶性肿瘤患者90例,随机均分为3组:对照组(C组)、体温保护组(T组)和体温保护联合右美托咪定组(T-D组),每组30例。C组常规体温保护,T组和T-D组综合体温保护;T-D组麻醉诱导前10 min泵注右美托咪定0.5 μg/kg。记录3组患者麻醉诱导开始时(T0)、手术开始30 min(T1)、60 min(T2)、90 min(T3)、120 min(T4)以及手术结束时(T5)的鼻咽温度;于T0、术后2 h(T6)、24 h(T7)和48 h(T8)时抽取静脉血标本,测定T淋巴细胞亚群(CD3+、CD4+和CD8+)和自然杀伤细胞(NK cell)水平;记录患者术中麻醉药物用量及苏醒期质量指标。结果 与T0比较,C组T2~T5时点鼻咽温度均明显降低(P < 0.05);与C组比较,T组和T-D组T2~T5时点鼻咽温度明显升高(P < 0.05)。与T0时点比较,C组、T组和T-D组T6、T7和T8时点CD3+和NK cell活性均明显降低(P < 0.05);C组在T6、T7和T8时点,T组和T-D组在T6和T7时点,CD4+活性均明显降低(P < 0.05)。与C组比较,T组和T-D组T6和T7时点CD3+细胞活性均明显升高(P < 0.05);T组在T7时点,T-D组在T6和T7时点,CD4+细胞活性均明显升高(P < 0.05);T组在T7时点,T-D组在T6、T7和T8时点,NK cell活性均明显升高(P < 0.05)。结论 采用体温保护措施联合右美托咪定能够维持老年恶性肿瘤患者的体温稳定,减少围手术期意外低体温(IPH)的发生,并有效提高患者苏醒期质量,减轻免疫抑制程度,加速患者早期恢复。  相似文献   
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BackgroundThe Fullerton Advanced Balance Scale (FAB) is a multi-item balance assessment test designed to measure balance in relatively higher functioning individuals. The aim of this study was to examine the reliability and validity of the Turkish version of the FAB (FAB-T) in children with cerebral palsy (CP).Research questionIs the Turkish version of the Fullerton Advance Balance Scale valid and reliable in determining balance problems in children with cerebral palsy and determining the underlying cause of this condition?MethodsForty-six children with CP participated in this study. Rasch analysis was used to investigate item adherence. Internal consistency of the FAB-T was established using Cronbach's alpha coefficient. Test-retest reliability was also evaluated. In addition, to assess concurrent validity, FAB-T scores were compared with the Pediatric Balance Scale (PBS) using the Spearman correlation coefficient.ResultsThe FAB-T showed satisfactory internal consistency (Cronbach's alpha value=0.94) and excellent test-retest reliability (ICC=0.99). The FAB and the PBS exhibited concurrent positive validity (r = 0.913; p < 0.001). All items of the FAB-T were found to fit the Rasch Model (Chi-square 16.01(df=20), p = 0.716).SignificanceThe FAB-T is a reliable and valid tool that can be used to measure balance skills and to identify the source of the problem in children with CP.  相似文献   
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吴娟娟  倪俊 《中国卒中杂志》2021,16(12):1278-1283
脑淀粉样血管病(cerebral amyloid angiopathy,CAA)的主要致病物质是β淀粉样蛋白,其 产生异常、清除障碍导致异常沉积,引起管壁破坏、管腔狭窄等病理变化,最终导致CAA。目前CAA的 具体发病机制尚不清楚,涉及的成分复杂。本文介绍了β淀粉样蛋白产生及清除的三种过程及其平 衡破坏的后续效应和主要影响因素,同时从病因分类的角度阐明CAA的类型。  相似文献   
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IntroductionHip displacement is common in cerebral palsy (CP) and is related to the severity of neurological and functional impairment. It is a silent, but progressive disease, and can result in significant morbidity and decreased quality of life, if left untreated. The pathophysiology of hip displacement in CP is a combination of hip flexor-adductor muscle spasticity, abductor muscle weakness, and delayed weight-bearing, resulting in proximal femoral deformities and progressive acetabular dysplasia. Due to a lack of symptoms in the early stages of hip displacement, the diagnosis is easily missed. Awareness of this condition and regular surveillance by clinical examination and serial radiographs of the hips are the key to early diagnosis and treatment.Hip surveillance programmesSeveral population-based studies from around the world have demonstrated that universal hip surveillance in children with CP allows early detection of hip displacement and appropriate early intervention, with a resultant decrease in painful dislocations. Global hip surveillance models are based upon the patients’ age, functional level determined by the Gross Motor Function Classification system (GMFCS), gait classification, standardized clinical exam, and radiographic indices such as the migration percentage (MP), as critical indicators of progressive hip displacement.ConclusionDespite 25 years of evidence showing the efficacy of established hip surveillance programmes, there is poor awareness among healthcare professionals in India about the importance of regular hip surveillance in children with CP. There is a need for professional organizations to develop evidence-based guidelines for hip surveillance which are relevant to the Indian context.  相似文献   
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《Human brain mapping》2021,42(7):1945
Having the means to share research data openly is essential to modern science. For human research, a key aspect in this endeavor is obtaining consent from participants, not just to take part in a study, which is a basic ethical principle, but also to share their data with the scientific community. To ensure that the participants'' privacy is respected, national and/or supranational regulations and laws are in place. It is, however, not always clear to researchers what the implications of those are, nor how to comply with them. The Open Brain Consent (https://open-brain-consent.readthedocs.io) is an international initiative that aims to provide researchers in the brain imaging community with information about data sharing options and tools. We present here a short history of this project and its latest developments, and share pointers to consent forms, including a template consent form that is compliant with the EU general data protection regulation. We also share pointers to an associated data user agreement that is not only useful in the EU context, but also for any researchers dealing with personal (clinical) data elsewhere.  相似文献   
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目的分析并探究双侧延髓内侧梗死(BMMI)的血管病因、临床表现、MRI特征和预后,以期提高BMMI的早期诊断率.方法对青岛大学附属烟台毓璜顶医院诊治的14例BMMI患者临床资料进行分析.结果BMMI血管病因以动脉粥样硬化为主;临床症状表现为四肢瘫痪、舌瘫、感觉异常、头晕、构音障碍、饮水呛咳等,危重时出现呼吸衰竭.头颅DWI示双侧延髓内侧可呈特征性"心型"、"Y"字型、"V"字型或倒"八"字型高信号影.出院NIHSS评分、卒中进展(尤其呼吸衰竭)为BMMI的预后不良因素.结论BMMI临床少见,临床表现多样,预后较差;头颅MRI为其主要的影像学检查,有助于早期诊断.  相似文献   
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《Clinical neurophysiology》2021,132(1):157-164
ObjectiveEarly EEG contains reliable information for outcome prediction of comatose patients after cardiac arrest. We introduce dynamic functional connectivity measures and estimate additional predictive values.MethodsWe performed a prospective multicenter cohort study on continuous EEG for outcome prediction of comatose patients after cardiac arrest. We calculated Link Rates (LR) and Link Durations (LD) in the α, δ, and θ band, based on similarity of instantaneous frequencies in five-minute EEG epochs, hourly, during 3 days after cardiac arrest. We studied associations of LR and LD with good (Cerebral Performance Category (CPC) 1–2) or poor outcome (CPC 3–5) with univariate analyses. With random forest classification, we established EEG-based predictive models. We used receiver operating characteristics to estimate additional values of dynamic connectivity measures for outcome prediction.ResultsOf 683 patients, 369 (54%) had poor outcome. Patients with poor outcome had significantly lower LR and longer LD, with largest differences 12 h after cardiac arrest (LRθ 1.87 vs. 1.95 Hz and LDα 91 vs. 82 ms). Adding these measures to a model with classical EEG features increased sensitivity for reliable prediction of poor outcome from 34% to 38% at 12 h after cardiac arrest.ConclusionPoor outcome is associated with lower dynamics of connectivity after cardiac arrest.SignificanceDynamic functional connectivity analysis may improve EEG based outcome prediction.  相似文献   
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