ABSTRACT
Background: Significant dysbiosis occurs in the gut microbiome of stroke patients. Condensing these broad, complex changes into one index would greatly facilitate the clinical usage of gut microbiome data. Here, we formulated a gut microbiota index in patients with acute ischemic stroke based on their gut microbiota dysbiosis patterns and tested whether the index was correlated with brain injury and early outcome. Methods: A total of 104 patients with acute ischemic stroke and 90 healthy individuals were recruited, and their gut microbiotas were compared and to model a Stroke Dysbiosis Index (SDI), which representing stroke-associated dysbiosis patterns overall. Another 83 patients and 70 controls were recruited for validation. The association of SDI with stroke severity (National Institutes of Health Stroke Scale [NIHSS] score) and outcome (modified Rankin scale [mRS] score: favorable, 0-2; unfavorable, >2) at discharge was also assessed. A middle cerebral artery occlusion (MCAO) model was used in human flora-associated (HFA) animals to explore the causal relationship between gut dysbiosis and stroke outcome. Results: Eighteen genera were significantly different between stroke patients and healthy individuals. The SDI formula was devised based on these microbiome differences; SDI was significantly higher in stroke patients than in healthy controls. SDI alone discriminated stroke patients from controls with AUCs of 74.9% in the training cohort and 84.3% in the validation cohort. SDI was significantly and positively correlated with NIHSS score on admission and mRS score at discharge. Logistic regression analysis showed that SDI was an independent predictor of severe stroke (NIHSS ≥8) and early unfavorable outcome (mRS >2). Mice receiving fecal transplants from high-SDI patients developed severe brain injury with elevated IL-17+ γδ T cells in gut compared to mice receiving transplants from low-SDI patients (all P < 0.05). Conclusions: We developed an index to measure gut microbiota dysbiosis in stroke patients; this index was significantly correlated with patients' outcome and was causally related to outcome in a mouse model of stroke. Our model facilitates the potential clinical application of gut microbiota data in stroke and adds quantitative evidence linking the gut microbiota to stroke.
ABSTRACT
BACKGROUND: Autism spectrum disorder (ASD) is a common severe pervasive neurodevelopmental disorder of undetermined etiology. Environmental exposures, especially pregnancy complications, have been increasingly recognized as a potential risk factor for ASD. Our aim was to (1) systematically evaluate the association between hypertensive disorders of pregnancy (HDP) and the risk of ASD in offspring, (2) specifically draw a subgroup analysis of disease severity in patients with HDP to achieve more sufficient evidence on this issue. RESULTS: A total of 21 studies were identified with more than 6.5 million participants, including 31,027 ASD probands. A comparative meta-analysis established that offspring born premature to HDP were significantly associated with ASD than matched controls (OR = 1.42, 95% CI: 1.34-1.50). Subgroup analysis of clinical classification include: (1) gestational hypertension, (2) pre-eclampsia, (3) chronic hypertension complicating pregnancy (CHP). The offspring of mothers with pre-eclampsia and CHP have slightly higher risk (OR = 1.43; OR = 1.48, respectively) of ASD than those of mothers with gestational hypertension (OR = 1.37). In consistence with most previous researches, higher ASD prevalence was observed in male than female (OR = 1.38), indicating a potential role for gender in the pathophysiology of ASD. MATERIALS AND METHODS: We conducted a systematic literature search on PubMed, EMBASE, Web of Science, PsycINFO database and China National Knowledge Infrastructure up to Jun. 2017. Statistical analysis was performed using Stata 10.0. CONCLUSIONS: This meta-analysis implies a possible link between HDP and the risk of ASD in offspring. However, further investigation should be conducted to confirm this conclusion, and intensive prenatal surveillance and early prediction for ASD is needed.
ABSTRACT
OBJECTIVE: To construct a luciferase reporter gene vector of p-selectin gene promoter and determine its transcriptional activity for screening the effect of drugs on the transcriptional activity of p-selectin promoter. METHODS: Primers were designed based on human p-selectin promoter sequence from UCSC software. The p-selectin promoter from human genome DNA was then amplified. After digestion of pGL3-Basic vector and p-selectin promoter with Kpn I and Xho I, p-selectin promoter was inserted into pGL3-basic vector. The recombinant plasmid, namely pGL3-p-selectin-promoter, was transiently cotransfected into 293F cells with pRL-SV40 as the control vector, and the activity of the dual luciferase was detected. The transcription activity of serially truncated segments of the p-selectin promoter reporter gene was quantified by luciferase expression. 293F cells transfected with pGL3-p-selectin-promoter reporter gene and dual luciferase were stimulated with LPS, TNF-α and As2O3, and the transcriptional activity of p-selectin promoter were assessed. RESULTS: pGL3-p-selectin-promoter was constructed successfully as verified by restriction digestion and sequence analysis. The luciferase activity was higher in pGL3-p-selectin-promoter/pRL-SV40 group than in pGL3-basic/pRL-SV40 group (0.8573±0.4703 vs 0.03955±0.05894). pGL3- 1826 bp was actively transcribed compared with pGL3-1092 bp and pGL3-3738 bp. LPS, TNF-α and As2O3 significantly enhanced the transcriptional activity of p-selectin promoter. CONCLUSION: pGL3-p-selectin-promoter can be transcribed and activated in 293F cells. This study provided an important basis for acquiring transcriptional factors and screening inflammatory factors and drugs.
