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This paper focuses on a class of functional diffusion systems with singularly perturbed regime switching, where the modulating Markov chain has a large state space and undergoes weak and strong interactions. By using the martingale method and weak convergence, this paper shows that the underlying system will weakly converge to a limit system, which is simpler than the original system. For a class of integro-differential diffusion system with singularly perturbed regime switching, as a class of special functional diffusion system, this paper demonstrates that if the limit system is moment exponentially stable, the original system with singular perturbation is also moment exponentially stable under suitable conditions. This result is interesting since the limit system is always simpler. Finally, an example is given to illustrate this result. [ABSTRACT FROM AUTHOR]

• Hemodynamic instability (HI) risk factors after carotid artery stenting are unclear • Smoking, distance to the carotid bulb, or large balloon predilation influence HI • General anesthesia can have a protective role against HI The risk factors for post-carotid artery stenting severe hemodynamic instability remain elusive. This study aimed to identify the predictors of severe hemodynamic instability during and persisted after carotid artery stenting. Consecutive patients who underwent carotid artery stenting for extracranial carotid artery stenosis at a single-center between September 2018 and July 2021 were retrospectively assessed. The predictive factors of severe hemodynamic instability intraoperation and post-operation were analyzed. Among the 139 patients included, 63 experienced severe hemodynamic instability, with 45 and 18 cases occurring intra and postoperatively, respectively. Persistent was observed in 21 patients. Smoke exposure (odds ratio [OR], 2.38; p=0.039), carotid bifurcation stenosis (OR, 0.91; p=0.018), and large-diameter balloon (>4 mm) dilatation (OR, 11.95; p<0.001) were identified as independent risk factors for hemodynamic instability at any stage of carotid artery stenting. Intraoperatively, large-diameter balloon (>4 mm) dilatation was associated with an increased risk of hemodynamic instability occurrence (OR, 4.67; p=0.01), whereas general anesthesia (OR, 0.19; p=0.001) and a longer distance from the stenosis to the carotid bifurcation (OR, 0.89; p=0.01) were negatively associated with hemodynamic instability. Furthermore, smoking exposure (OR, 3.73; p=0.03), large diameter balloon dilatation (OR, 6.12; p=0.032), distance from stenosis to bifurcation (OR, 0.85; p=0.047) and long-stent (40 mm) implantation (OR, 0.84 [95% confidence interval, 0.74–0.95]; p=0.007) could independently predict persistent hemodynamic instability. Patients with a smoking history, lesions near the carotid bulb, or dilatation using a large-diameter balloon were most likely to suffer severe hemodynamic instability. General anesthesia can protect against severe hemodynamic instability only intraoperatively. Long-term stent implantation may reduce persistent hemodynamic instability. [ABSTRACT FROM AUTHOR]

Anterior cerebral artery (ACA) flow diversion (FD), defined as ipsilateral mean velocity (MV) of at least 30% greater than the contralateral artery, could be seen an indirect sign of leptomeningeal collateralization in the setting of middle cerebral artery occlusion. The purpose of the study was to evaluate the association between dynamic FD and functional outcome in acute anterior stroke patients with large artery occlusion. Acute middle cerebral artery (MCA) or internal carotid artery (ICA) occlusive stroke patients within 12 h were recruited. Transcranial Doppler ultrasound was done at baseline, 24 h and 7 d after onset and velocities of MCA and ACA were recorded. FD ratio was calculated by dividing the ipsilateral ACA MV by the contralateral ACA MV. FD was determined positive when FD ratio ≥1.3. Outcome was assessed by 90-day modified Rankin’s Scale (mRS). The association between FD at different time points and functional outcome were analyzed. 16 patients (median age of 67 and 75% were male) were recruited. FD ratio showed a trend of decline but did not reach statistical significance (p = 0.056). The proportion of FD at baseline (p = 0.026), 24 h (p = 0.001) and 7d (p = 0.044) was significantly higher in patients with favorable outcome. Higher FD ratio at baseline (p = 0.02) and 24 h (p = 0.003) were significantly associated with favorable outcome. These results suggested that FD ratio showed a trend of decline after stroke onset. Presence of FD within 7 days was associated with favorable functional outcome in acute MCA/ICA occlusive stroke patients. [ABSTRACT FROM AUTHOR]

Background: Intravenous thrombolysis and intra-arterial thrombectomy are now the standard therapies for patients with acute ischemic stroke. In-house strokes have often been overlooked even at stroke centers and there is no consensus on how they should be managed. Perioperative stroke happens rather frequently but treatment protocol is lacking, In China, the issue of in-house strokes has not been explored. The aim of this study is to explore the current management of in-house stroke and identify the common risk factors associated with perioperative strokes.Method: Altogether, 51,841 patients were admitted to a tertiary hospital in Shanghai and the records of those who had a neurological consult for stroke were reviewed. Their demographics, clinical characteristics, in-hospital complications and operations, and management plans were prospectively studied. Routine laboratory test results and risk factors of these patients were analyzed by multiple logistic regression model.Result: From January 1, 2015, to December 31, 2015, over 1800 patients had neurological consultations. Among these patients, 37 had an in-house stroke and 20 had more severe stroke during the postoperative period. Compared to in-house stroke patients without a procedure or operation, leukocytosis and elevated fasting glucose levels were more common in perioperative strokes. In multiple logistic regression model, perioperative strokes were more likely related to large vessel occlusion.Conclusion: Patients with perioperative strokes had different risk factors and severity from other in-house strokes. For these patients, obtaining a neurological consultation prior to surgery may be appropriate in order to evaluate the risk of perioperative stroke. [ABSTRACT FROM AUTHOR]

[Display omitted] • Prophylactic use of probiotics before gastrectomy reduces inflammatory responses in patients. • Prophylactic administration of probiotics before gastrectomy can alleviate postoperative insulin resistance in patients. • A possible mechanism by which probiotic use of probiotics accelerates postoperative recovery in patients with gastric cancer after gastrectomy is to restore gut microbiota balance. Gastrectomy can improve the clinical survival rate of gastric cancer patients, while the metabolic disorders caused by gastrectomy, seriously affect the postoperative recovery. In this study, probiotics (including Bifidobacterium infantis , Lactobacillus acidophilus , Enterococcus faecalis and Bacillus cereus) were used before gastrectomy to explore the effect of probiotics on gastrectomy patients. Our outcomes revealed probiotics could alleviate postoperative inflammation (Leukocyte; P < 0.05), improve the metabolic disorder (fasting glucose; fasting insulin; HOMA-IR; P < 0.05), reduce the incidence of postoperative insulin resistance (IR; P < 0.001) and infectious complications (P < 0.05). Besides, the probiotics greatly enriched the relative abundance of bacteria Faecalibacterium prausnitzii and Gemmiger formicilis , while decreased the pathogenic Bacteroides fragilis , Prevotella copri and Clostridium difficile at the species levels. Therefore, we believe that preventive use of probiotics can reduce postoperative inflammation, alleviate metabolic disorder, reduce insulin resistance, restore intestinal microecological balance, and finally promote early recovery of patients. [ABSTRACT FROM AUTHOR]

Background/objective: We sought to assess the different patterns of cerebral hemodynamic changes in staged carotid angioplasty and stenting (CAS).Methods: We prospectively recruited a cohort of patients with regular angioplasty or staged angioplasty from October 2013 to August 2015. The hemodynamic changes, including peak systolic, end-diastolic, and mean flow velocities in the ipsilateral middle cerebral artery (MCA) and the contralateral anterior cerebral artery (ACA), were recorded by transcranial Doppler ultrasound.Results: Between October 2013 to August 2015, 25 patients (age range from 48 to 78 years, 96% male) with CAS were recruited, of whom 13 patients received staged angioplasty and 12 patients received regular angioplasty. Patients in the staged angioplasty group showed a higher degree of stenosis in the internal carotid artery. After the procedure, the peak systolic, diastolic, and mean flow velocities in the ipsilateral MCA in the staged angioplasty group were significantly higher than those in the regular angioplasty group (P = .028, .036, and .027, respectively). In the staged angioplasty group, first, the peak systolic, end-diastolic, and mean flow velocities in the contralateral ACA decreased significantly soon after balloon dilation in stage I (P = .042, .033, and .034, respectively). Second, the peak systolic, diastolic, and mean flow velocities in the ipsilateral MCA increased after stent placement in stage II (P = .006, .042, and .003, respectively).Conclusions: Two-stage hemodynamic changes were observed in staged angioplasty. The velocities in the ipsilateral MCA started to increase significantly after the collateral flow diminished. [ABSTRACT FROM AUTHOR]

Background We sought to assess the association of left ventricle mass (LVM) indices with the functional outcome of acute ischemic stroke (AIS) patients after intravenous tissue plasminogen activator (IV-tPA). Methods Consecutive AIS patients with IV-tPA were recruited. LVM indices including LVM/weight, LVM/surface, and LVM/heightˆ 2.7 on echocardiogram during hospitalization were retrospectively reviewed. Outcome was 90-day modified Rankin scale (mRS) scores. Multivariate logistic regression was performed to analyze the association of LVM indices with outcome. Results Between August 2010 and May 2014, 55 AIS patients (age range from 27 to 78 years, 69.1% men) with echocardiogram after thrombolysis were recruited. Lower baseline National Institutes of Health Stroke Scale (NIHSS; P = .009) and higher LVM indices (LVM/weight [ P = .012], LVM/surface [ P = .039], and LVM/heightˆ 2.7 [ P = .045]) were significantly associated with 90-day favorable outcome (mRS, 0-2). In multivariate logistic regression analysis, LVM/weight independently predicted good outcome with an odds ratio of 3.89 (95% confidence interval, 1.05-14.42, P = .042) after adjustment for baseline NIHSS, onset-to-treatment time, hypertension, hemorrhagic transformation, and systolic left ventricle inner diameters. Conclusions Higher LVM indices on echocardiogram are significantly associated with favorable outcome in stroke patients with IV-tPA, among which LVM/weight seems to be the most effective. [ABSTRACT FROM AUTHOR]

Background We aimed to test the outcome-predictive power of routine fasting glucose (FG) obtained at second day after onset in intravenous thrombolysis (IVT) acute ischemic stroke (AIS) patients. Methods We identified AIS patients presenting to our institution between December 2011 and July 2013 within 4.5 hours of onset, who received admission glucose (AG) before IVT, FG, and glycated hemoglobin (HbA1c) the second day after admission, from our prospectively recorded stroke database. Multivariate logistic regression was used to assess the association of FG and 90-day modified Rankin Scale (mRS). Results Between December 2011 and July 2013, a total of 166 AIS patients received intravenous plasminogen activator. Of those, 119 patients who have AG before IVT, FG, and HbA1c the second day were included in the study. FG independently predicted 90-day clinical unfavorable outcome (mRS, 3-6 with an odds ratio of 1.576; 95% confidence interval [CI], 1.053-2.358; P = .027). This association was not significant in AG ( P = .714), HbA1c ( P = .655), and history of diabetes ( P = .547). In receiver operating characteristic analysis, increased FG was associated with 90-day mRS (3-6) with an area under curve of .72, (95% CI, .65-.9; P = .001). Conclusions FG is a powerful predictor associated with the outcome in IVT-treated AIS patients independent of AG and HbA1c. [ABSTRACT FROM AUTHOR]

Background Spinal dural arteriovenous fistula (SDAVF) is a rare disorder with the presenting of nonspecific clinical symptoms and signs at onset, which can be a challenge to diagnose promptly and leads to the overusing of spinal digital subtraction angiography (SpDSA) in clinical practice. The purpose of this study was to find specific characteristics of SDAVF by comparing the clinical and radiologic data between the SpDSA-identified patients with SDAVF and SpDSA-negative patients, who were suspected with spinal vascular diseases before admission. Methods From 2006 to 2011, patients presented to Huashan hospital with spinal symptoms and who received SpDSA were retrospectively analyzed. Comparisons of clinical and magnetic resonance imaging data were performed between SpDSA-identified SDAVF and SpDSA-negative patients. We derived a diagnostic criteria score and assessed likely clinical usefulness to predict the SDAVF using the score to stratify all patients with suspected. Results Four independent predictors (age ≥50 years, length of intramedullary lesion ≥5 vertical segments, perimedullary dilated vessels, and subcervical lesion) tested out by multivariable logistic regression and receiver operating characteristic analysis were significantly associated with SDAVF. A 4-point score (AVFS) including those criteria predicted the SpDSA-identified SDAVF with an area under the curve of .91 (95% confidence interval [CI] .84-.97, P < .001). A threshold of AVFS of 3 or more predicted SDAVF with a sensitivity of 85% (95% CI 62%-96%) and a specificity of 97% (95% CI 86%-99%). Conclusion The AVFS score may be useful in routine clinical practice to identify high-risk individuals with SDAVF who need further confirmation with SpDSA. [ABSTRACT FROM AUTHOR]

Background: Massive ipsilateral edema in patients with cerebral dural arteriovenous fistula (DAVF) is poorly documented. The present study better characterizes this condition through assessment of venous anatomy and potential underlying mechanisms. Methods: One hundred and two consecutive patients diagnosed with DAVF and admitted to the Huashan Hospital from 2006 to 2012 were retrospectively reviewed for the clinical and radiologic data, and those with ipsilateral edema were recruited. An edema scale was calculated from the locations with edema on magnetic resonance imaging. We created a reflux anatomic venous scale (RAVS, including veins of Labbe, Sylvian, and Troland) based on DSA. Two experienced interventional neuroradiologists independently assessed the images and then reached consensus. The Spearman nonparametric rank correlation was performed to analyze the correlation between edema scale and RAVS. Results: Seven patients (mean 61 ± 13 years; 4 men:3 women) with ipsilateral intracranial edema were finally included. DAVF in transverse sinus with reflux flow initially in vein of the Labbe was seen in all patients. Increased edema scale was significantly correlated with increased RAVS (Spearman rho = .856, P = .014). Conclusion: The present study indicated that severe ipsilateral edema, with reflux flow initially in vein of the Labbe, was associated with the increased number of reflux anatomic veins in transverse sinus DAVF. [Copyright &y& Elsevier]

Abstract: Cerebrovascular reserve (CVR) is an important prognostic factor in patients with major cerebral arterial steno-occlusive disease. However, few studies have examined CVR in symptomatic intracranial stenosis without ipsilateral extracranial internal carotid artery stenosis. This study sought to evaluate CVR in patients with symptomatic middle cerebral artery (MCA) stenosis using xenon-enhanced computed tomography (Xe/CT) with acetazolamide (ACZ) challenge. Twelve patients with symptomatic MCA stenosis were recruited. All patients were examined by Xe/CT to quantitatively measure resting cerebral blood flow (CBF) and received ACZ challenge to evaluate CVR. For resting CBF, no significant differences were found between the sides in four regions of interest. After the ACZ challenge test, the CVR was significantly different between hemispheres (ipsilateral versus contralateral CVR: 12.9±24.3% versus 28.0±16.8%, respectively; p =0.005) and in the MCA territory (ipsilateral versus contralateral CVR: 8.7±24.7% versus 29.3±24%, respectively; p =0.003). However, no significant differences in CVR were detected between cortical comparisons and white matter comparisons from the two sides. Thus, ACZ-challenge Xe/CT is useful for the measurement of CBF and CVR in these patients. Impaired CVR is an important characteristic of patients with symptomatic MCA stenosis. [Copyright &y& Elsevier]

The value of CT perfusion (CTP) in detecting acute lacunar infarcts (LACI) has not been well established. We tested the sensitivity of CTP for LACI. CTP maps of consecutive stroke patients from 2009–2013 were examined. MRI diffusion imaging was used to identify those with LACI. Two stroke neurologists independently evaluated the CTP maps for evidence of a perfusion lesion in a deep perforating artery territory. Cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT) and time to maximum (Tmax) maps were first examined in isolation and then in combination. Inter-observer agreement was measured using Cohen’s κ. The lesions identified were later confirmed against the diffusion MRI reference and the sensitivity and specificity of CTP maps calculated. A total of 63 patient scans were analysed. There were 32 patients with MRI-confirmed LACI within the coverage of CTP; 18 in the striatum, 10 thalamic, and four in the corona radiata. Another 31 patients had normal MRI. Inter-rater agreement was good (κ = 0.83). Sensitivity (blinded consensus) was highest for MTT (56.2%) compared to Tmax (25%, p < 0.001), CBV (9.3%, p = 0.021) and CBF (43.7%, p < 0.001). MTT maps enable detection of a significant proportion of LACI using CTP. [ABSTRACT FROM AUTHOR]