From A to E: Uniting vitamins against stroke risk-A systematic review and network meta-analysis

BACKGROUND AND AIM

Stroke represents a significant public health challenge, necessitating the exploration of preventive measures. This network meta-analysis aimed to assess the efficacy of different vitamin treatments compared to a placebo in preventing stroke.

METHODS

A systematic electronic search in databases including PubMed, EmBASE, Web of Science, clinicaltrials.gov, and Google Scholar until 31 May 2023 was conducted, to identify published studies investigating the association between vitamin intake and the risk of stroke. Pooled risk ratio (RR) with 95% confidence intervals (CIs) was calculated using a frequentist network meta-analysis. Furthermore, we ranked vitamins based on p-scores, facilitating a comparative assessment of their effectiveness in preventing stroke.

RESULTS

A total of 56 studies, including 17 randomized controlled trials (RCTs) and 39 cohort studies were analyzed. Direct estimates obtained from network meta-analysis, we found that vitamin A (RR: .81 [.72-.91]), vitamin B-complex (RR: .85 [.74-.97]), vitamin B6 (RR: 79 [.68-.92]), folate (RR: .86 [.75-.97]), vitamin C (RR: .77 [.70-.85]) and vitamin D (RR: .73 [.64-.83]) were significantly associated with a decreased stroke risk. However, no significant association was observed for vitamin B2 , vitamin B12 , and vitamin E. Subsequent to network meta-analysis, vitamins were ranked in decreasing order of their efficacy in stroke prevention based on p-score, with vitamin D (p-score = .91), vitamin C (p-score = .79), vitamin B6 (p-score = .70), vitamin A (p-score = .65), vitamin B-complex (p-score = .53), folate (p-score = .49), vitamin B2 (p-score = .39), vitamin E (p-score = .28), vitamin B12 (.13) and placebo (.10).

CONCLUSION

Our study has established noteworthy connections between vitamin A, vitamin B-complex, vitamin B6 , folate, vitamin C, and vitamin D in the realm of stroke prevention. These findings add substantial weight to the accumulating evidence supporting the potential advantages of vitamin interventions in mitigating the risk of stroke. However, to solidify and validate these observations, additional research is imperative. Well-designed clinical trials or cohort studies are needed to further explore these associations and formulate clear guidelines for incorporating vitamin supplementation into effective stroke prevention strategies.

Phosphodiesterase 4 D (PDE4D) gene polymorphisms and risk of ischemic stroke: A systematic review and meta-analysis

BACKGROUND AND PURPOSE

Studies on the relationship between Phosphodiesterase 4 D (PDE4D) gene polymorphism with the risk of ischemic stroke (IS) have shown discordant results. The present meta-analysis was aimed to clarify the relationship between PDE4D gene polymorphism with the risk of IS by estimating pooled analysis of published epidemiological studies.

METHODS

A comprehensive literature search for all the published articles was performed in various electronic databases, including PubMed, EMbase, Cochrane Library, Trip Database, Worldwide Science, CINAHL, and Google Scholar up to 22nd December 2021. Pooled Odds ratios (ORs) with 95% Confidence Intervals (CIs) under dominant, recessive, and allelic models were calculated. Subgroup analysis based on ethnicity (Caucasian vs. Asian) was performed to examine the reliability of these findings. Sensitivity analysis was also performed to detect the heterogeneity between studies. Finally, Begg's funnel plot was used to assess the potential for publication bias.

RESULTS

In our meta-analysis, we identified a total of 47 case-control studies with 20,644 ischemic stroke (IS) cases and 23,201 control subjects, including 17 studies of Caucasian descent and 30 studies of Asian descent. Our findings suggest that there was a significant relationship between SNP45 gene polymorphism and risk of IS (Recessive model: OR = 2.06, 95% CI 1.31-3.23), SNP83 overall (allelic model: OR = 1.22, 95% CI 1.04-1.42), Asian (allelic model: OR = 1.20, 95% CI 1.05-1.37), and SNP89 Asian (Dominant model: OR = 1.43, 95% CI 1.29-1.59, recessive model: OR = 1.42, 95% CI 1.28-1.58) respectively. However, no significant relationship was found between SNP32, SNP41, SNP26, SNP56, and SNP87 gene polymorphisms and risk of IS.

CONCLUSION

Findings of this meta-analysis conclude that SNP45, SNP83, and SNP89 polymorphism could be capable of increasing stroke susceptibility in Asians but not in the Caucasian population. Genotyping of SNP 45, 83, 89 polymorphisms may be used as a predictor for the occurrence of IS.

Does treatment modality affect measures of arterial stiffness in women with gestational diabetes?

OBJECTIVE

To investigate whether arterial stiffness (AS) differs between healthy women and women with gestational diabetes mellitus (GDM) managed by different treatment modalities.

METHODS

This was a prospective longitudinal cohort study comparing AS in pregnancies complicated by GDM and low-risk controls. AS was assessed by recording aortic pulse-wave velocity (AoPWV), brachial augmentation index (BrAIx) and aortic augmentation index (AoAIx) using the Arteriograph® at four gestational-age windows: 24 + 0 to 27 + 6 weeks (W1); 28 + 0 to 31 + 6 weeks (W2); 32 + 0 to 35 + 6 weeks (W3) and ≥ 36 + 0 weeks (W4). Women with GDM were considered both as a single group and as subgroups stratified by treatment modality. Data were analyzed using a linear mixed model on each AS variable (log-transformed) with group, gestational-age window, maternal age, ethnicity, parity, body mass index, mean arterial pressure and heart rate as fixed effects and individual as a random effect. We compared the group means including relevant contrasts and adjusted the P-values using Bonferroni correction.

RESULTS

The study population comprised 155 low-risk controls and 127 women with GDM, of whom 59 were treated with dietary intervention, 47 were treated with metformin only and 21 were treated with metformin + insulin. The two-way interaction term of study group and gestational age was significant for BrAIx and AoAIx (P < 0.001), but there was no evidence that mean AoPWV was different between the study groups (P = 0.729). Women in the control group demonstrated significantly lower BrAIx and AoAIx compared with the combined GDM group at W1-W3, but not at W4. The mean difference in log-transformed BrAIx was -0.37 (95% CI, -0.52 to -0.22), -0.23 (95% CI, -0.35 to -0.12) and -0.29 (95% CI, -0.40 to -0.18) at W1, W2 and W3, respectively. The mean difference in log-transformed AoAIx was -0.49 (95% CI, -0.69 to -0.30), -0.32 (95% CI, -0.47 to -0.18) and -0.38 (95% CI -0.52 to -0.24) at W1, W2 and W3, respectively. Similarly, women in the control group also demonstrated significantly lower BrAIx and AoAIx compared with each of the GDM treatment subgroups (diet, metformin only and metformin + insulin) at W1-W3. The increase in mean BrAIx and AoAIx seen between W2 and W3 in women with GDM treated with dietary management was attenuated in the metformin-only and metformin + insulin groups. However, the mean differences in BrAIx and AoAIx between these treatment groups were not statistically significant at any gestational-age window.

CONCLUSIONS

Pregnancies complicated by GDM demonstrate significantly higher AS compared with low-risk pregnancies regardless of treatment modality. Our data provide the basis for further investigation into the association of metformin therapy with changes in AS and risk of placenta-mediated diseases. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Decompressive surgery in cerebral venous thrombosis: A systematic review and meta-analysis

OBJECTIVE

The efficacy of decompressive surgery (DS) in cerebral venous thrombosis (CVT) patients has been reported in several case reports and case series. We aimed at determining the association of DS compared with medical management and timing of surgery with functional outcome and mortality. We also aimed at determining the prevalence of DS in CVT patients.

METHODS

The literature search was conducted till 7 November 2022 in PubMed, Google Scholar, EMBASE and Cochrane Library databases. Risk of bias was examined using Joanna Briggs Institute scale for case series and case reports. Association of DS compared with medical management and timing of surgery with functional outcome and mortality was determined using odds ratio (OR) and 95% confidence interval (CI). Pooled prevalence of DS in CVT patients with 95%CI was calculated. Heterogeneity was explored using outlier, meta-regression, sensitivity and subgroup analyses.

RESULTS

Fifty-one studies consisting of 483 CVT cases with DS were included. The OR of poor outcome with surgery was 0.03; (95%CI: 0.00-0.22) and of mortality with surgery was 0.25; (95%CI: 0.02-2.60) versus that with medical management. Surgery done ≤48 h of admission was significantly associated with less mortality (OR: 0.26; 95%CI: 0.10-0.69). Pooled prevalence of DS in CVT was 12% (95%CI: 8%-17%; I²  = 91%). Revised pooled prevalence after removing outliers was 10% (95%CI: 7%-13%; I²  = 73%).

CONCLUSIONS

Surgery ≤48 h of admission might decrease mortality in CVT patients and may result in improved functional outcome. Further prospective studies with appropriate control arms are required to confirm its efficacy over medical management.

Frequency of Defecation and Form of Stool among General Bangladeshi Population

Data on stool form and defecation frequency which are a prerequisite for defining normal bowel habit are lacking in Bangladesh. This observational cross sectional study was designed to find out defecation frequency and stool form among general population in Bangladesh. This study was performed in the Department of Gastroenterology, Shaheed Suhrawardy Medical College Hospital, Dhaka, Bangladesh from July 2017 to June 2018. Apparently healthy 1090 respondents were evaluated for predominant stool form (Bristol chart) and frequency. Data on demographic and life-style were collected. The study population consisted of 1090 respondents, among them, 65.13% male and 34.87% female and mean age of them was 40.20±12.39 years. Most of the people 874(80.2%) passed stool between 12-14 times per week followed by 111(10.2%) less than 3 stools per week, 95(8.7%) passed more than 14 stools per week and 10(0.9%) between 3-12 stools per week, p<0.001. Most people passed predominantly Bristol type IV stool- 610(56.0%); followed by type III- 274(25.1%). Other stool forms were: type I- 52(4.8%), type II- 59(5.4%), type V- 31(2.8%), type VI- 33(3.0%), type VII- 31(2.8%), p<0.001. In regard to the physical activity, most of the respondents (70.0%) are physically active whereas about 13.0% are sedentary and about 17.0% are physically intermediate between the two, p<0.001. In the case of dietary habit, most of the participants are non-vegetarian (82.5%) and the remaining are vegetarian (11.1%) and occasional non vegetarian (6.4%), p<0.001. Median stool frequency in the studied population was 14 per week and predominant form was Bristol type IV. Older age was associated with lesser stool frequency, particularly among female subjects.

Association of modifiable risk factors with ischaemic stroke subtypes in Asian versus Caucasian populations: A systematic review and meta-analysis

BACKGROUND

Ischaemic stroke (IS) is associated with various modifiable risk factors but the association of these risk factors based on TOAST classification, which characterises IS into five subtypes: large artery atherosclerosis (LAA), small vessel occlusion (SVO), cardioembolic disease (CE), other determined aetiology (ODE) and undetermined aetiology (UDE), is unknown. We aimed to summarise the published evidence for the association of modifiable risk factors with IS subtypes based on TOAST classification, specifically focussing on the Asian versus Caucasian population.

METHOD

A comprehensive search for all the published articles was performed in electronic databases including PubMed, EMBASE, Cochrane Library, and Google Scholar from 01st January 1950 to 10th April 2022 based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Odds ratio (OR) with 95% confidence interval (CIs) along with random-effect models was used to calculate summary estimates.

RESULTS

In our meta-analysis, 32 studies with a total of 23,404 IS (14,364 in Asian vs. 9040 in Caucasian population), 7121 LAA (5219 in Asian vs. 1902 in Caucasian), 5532 SVO (3604 in Asian vs. 1928 in Caucasian), 3498 CE (1634 in Asian vs. 1864 in Caucasian), 1131 ODE (546 in Asian vs. 585 in Caucasian) and 4519 UDE (2076 in Asian vs. 2443 in Caucasian) were included. Our findings suggest a significant association between LAA and hypertension (OR = 1.07, 95% CI = 1.02-1.12), smoking (OR = 1.11, 95% CI = 1.04-1.17), dyslipidemia (OR = 1.13, 95% CI = 1.06-1.21), diabetes mellitus (OR = 1.18, 95% CI = 1.11-1.25) and atrial fibrillation (OR = 0.55, 95% CI = 0.40-0.75). Significantly strong association of hypertension, smoking, dyslipidemia, diabetes mellitus and atrial fibrillation was observed with SVO and CE stroke subtypes. Subgroup analysis based on ethnicity revealed a significant association for dyslipidemia, diabetes mellitus and atrial fibrillation in LAA for both Asians and Caucasians. Hypertension was significantly associated with SVO and ODE subtypes in both Asians and Caucasians; however, only Asian population showed significant association of hypertension in LAA and CE subtypes. The other risk factors did not show any statistical difference between the ethnic groups for the different stroke subtypes. The majority of the risk factors depicted positive association with LAA and SVO, negative with CE and neutral with ODE and UDE.

CONCLUSION

Our findings suggest strong association of smoking, dyslipidemia and diabetes mellitus with LAA and SVO subtypes in the Caucasian population. However, only diabetes mellitus showed significant association with both LAA and SVO subtypes in Asian population as well. Thus, a majority of the traditional modifiable risk factors had a positive association in LAA and SVO, while a negative protective association was observed in CE subtype, among both the Asian and the Caucasian subgroups.

Blood-based protein biomarkers for the diagnosis of acute stroke: A discovery-based SWATH-MS proteomic approach

Background and purposes

Recent developments in high-throughput proteomic approach have shown the potential to discover biomarkers for diagnosing acute stroke and to elucidate the pathomechanisms specific to different stroke subtypes. We aimed to determine blood-based protein biomarkers to diagnose total stroke (IS+ICH) from healthy controls, ischemic stroke (IS) from healthy controls, and intracerebral hemorrhage (ICH) from healthy control subjects within 24 h using a discovery-based SWATH-MS proteomic approach.

Methods

In this discovery phase study, serum samples were collected within 24 h from acute stroke (IS & ICH) patients and healthy controls and were subjected to SWATH-MS-based untargeted proteomics. For protein identification, a high-pH fractionated peptide library for human serum proteins (obtained from SCIEX) comprising of 465 proteins was used. Significantly differentially expressed (SDE) proteins were selected using the following criteria: >1.5-fold change for upregulated, < 0.67 for downregulated, p-value < 0.05, and confirmed/tentative selection using Boruta random forest. Protein–protein interaction network analysis and the functional enrichment analysis were conducted using STRING 11 online tool, g:Profiler tool and Cytoscape 3.9.0 software. The statistical analyses were conducted in R version 3.6.2.

Results

Our study included 40 stroke cases (20 IS, 20 ICH) within 24 h and 40 age-, sex-, hypertension-, and diabetes-matched healthy controls. We quantified 375 proteins between the stroke cases and control groups through SWATH-MS analysis. We observed 31 SDE proteins between total stroke and controls, 16 SDE proteins between IS and controls, and 41 SDE proteins between ICH and controls within 24 h. Four proteins [ceruloplasmin, alpha-1-antitrypsin (SERPINA1), von Willebrand factor (vWF), and coagulation factor XIII B chain (F13B)] commonly differentiated total stroke, IS, and ICH from healthy control subjects. The most common significant pathways in stroke cases involved complement and coagulation cascades, platelet degranulation, immune-related processes, acute phase response, lipid-related processes, and pathways related to extracellular space and matrix.

Conclusion

Our discovery phase study identified potential protein biomarker candidates for the diagnosis of acute stroke and highlighted significant pathways associated with different stroke subtypes. These potential biomarker candidates warrant further validation in future studies with a large cohort of stroke patients to investigate their diagnostic performance.

Micro-embolic signal monitoring in stroke subtypes: A systematic review and meta-analysis of 58 studies

Introduction

Micro-embolic signals (MESs) detected using transcranial Doppler (TCD) help in risk stratification in stroke patients. A systematic review and meta-analysis were performed to estimate the prevalence of MES and its association with stroke recurrence, functional outcome, and mortality in different stroke subtypes.

Methods

A comprehensive literature search was conducted before 26^th January 2021 in PubMed, Embase, Google Scholar, Cochrane Library, and ClinicalTrials.gov. Studies were identified that used TCD to detect MES in stroke/TIA patients. Pooled prevalence and odds ratio (OR) along with 95% confidence interval (95% CI) were calculated for different outcome measures. The entire statistical analysis was conducted in R version 3.6.2.

Findings

Fifty-eight studies involving 5123 patients (1329 MES+, 3794 MES-) were included in our meta-analysis. The pooled prevalence of MES among all acute stroke/TIA patients was 30% (95% CI 25-34%). The pooled prevalence adjusted after the trim-and-fill analysis among all acute stroke/TIA patients was 18% (95% CI 14-23%). The prevalence of MES was high among all stroke subtypes except in patients with small vessel disease (SVD). In patients with new-onset stroke/TIA, the presence of MES was associated with a high risk of recurrence of cerebral ischemia (OR 4.03; 95% CI 2.38-6.82). Although no significant association was observed for the presence of MES with increased mortality (OR 2.37; 95% CI 0.75-7.50) and poor functional outcome (OR 2.11; 95% CI 0.20-22.50) among patients with new-onset stroke/TIA, this could only be determined in a smaller sample size of 477 patients.

Conclusions

Our meta-analysis showed a 30% prevalence of MES following acute stroke/TIA. The presence of MES increased the chance of recurrence of cerebral ischemia but was not associated with poor functional outcomes and mortality in the studied subgroup.

Carotid intima-media thickness and risk of mild cognitive impairment: A systematic review and meta-analysis

Mild cognitive impairment (MCI) is an early phase of cognitive decline signalling the beginning of severe neurological diseases. Carotid intima-media thickness (cIMT) has shown some correlation with MCI development. This study was conducted to investigate the impact of elevated cIMT on the risk of MCI in adults. A literature search was conducted in PubMed, EMBASE, Cochrane Library, Scopus, Google Scholar and CINAHL databases till 30 July 2021, with keywords: ('Carotid Intima-Media Thickness' OR 'cIMT' OR 'IMT' AND 'Cognitive Impairment' OR 'Cognition' OR 'Cognitive Decline' AND 'Mild Cognitive Impairment' OR 'MCI'). Pooled standardized mean difference (SMD)/odds ratio (OR) and 95% confidence interval (CI) were determined for factor-disease association using either fixed (when I² <50%) or random effect (when I² >50%) models. Eight studies involving 1,585 MCI cases and 6,700 normal subjects were included in our meta-analysis which showed no significant association of increased cIMT with the risk of MCI [SMD 1.17, 95% CI -0.09 to 2.42]. However, sensitivity analysis revealed an outlier study significantly affecting the effect size. On omitting the outlier study, the re-evaluated meta-analysis revealed a significant association of cIMT with the risk of MCI [SMD 0.52, 95% CI 0.26 to 0.78]. This significant association was also observed during subgroup analysis in Caucasian population [SMD 0.65, 95% CI 0.13 to 1.18] but not in Asian population [SMD 0.39, 95% CI -0.01 to 0.79]. Elevated cIMT poses a potential risk for MCI. However, more population-based studies are required to corroborate these findings.

Cystatin C and Risk of Mild Cognitive Impairment: A Systematic Review and Meta-Analysis

INTRODUCTION

Cystatin C (Cys C) has been found as a novel biomarker of neurodegenerative diseases, such as dementia and Alzheimer's disease. Published studies on the role of Cys C as a biomarker of mild cognitive impairment (MCI) have not been reviewed systematically.

OBJECTIVE

Present meta-analysis was performed to elucidate the association between Cys C and risk of MCI.

METHODS

A comprehensive search was performed in PubMed, EMBASE, Cochrane Library, Trip databases, Worldwide Science, and Google Scholar from January 1, 1950, to April 30, 2020. Standardized mean difference (SMD) with 95% confidence interval (CI) using fixed or random effect models were used to calculate summary estimates. Quality of evidence was also assessed using the Diagnostic Accuracy Quality Scale (DAQS) and grading quality of evidence and strength of recommendations approach.

RESULTS

In our meta-analysis, 12 studies with a total of 2,433 MCI patients and 1,034 controls were included. Our findings suggest a strong association between increased levels of Cys C and risk of MCI as compared to control subjects (SMD = 2.39, 95% CI = 0.22-4.57). Subgroup analysis based on ethnicity, a significant association for the high level of Cys C with the risk of MCI was observed in the Asian population (SMD = 1.63, 95% CI = 0.44-2.82) but not in the Caucasian population (SMD = 2.80, 95% CI = [-0.66]-6.26).

CONCLUSION

Cys C was associated with MCI, and it could be considered as a predictor for the risk of cognitive impairment.

Association between Angiotensin Converting Enzyme Insertion/Deletion gene polymorphism with the risk of Hemorrhagic Stroke: A systematic review and Meta-Analysis of 53 studies

BACKGROUND AND AIMS

Hemorrhagic stroke (HS) results in significant mortality and disability worldwide. Angiotensin Converting Enzyme (ACE) is responsible for blood pressure regulation and vascular homeostasis. Our objective was to conduct a comprehensive meta-analysis for ascertaining the association of ACE I/D polymorphism with HS since a number of studies depicted inconclusive evidence.

METHODS

Literature search was performed till July 10, 2020 in PubMed, EMBASE, Cochrane, Chinese National Knowledge Information and Google Scholar databases with keywords: ('Angiotensin Converting Enzyme' OR 'ACE') AND ('Single Nucleotide polymorphisms' OR 'SNP') AND ('Hemorrhagic stroke or 'HS'). Pooled Odds Ratio (OR) and 95% Confidence Interval (CI) were determined for gene-disease association using either fixed (when I² < 50%) or random effect (when I² > 50%) models. Risk of bias in studies was assessed using funnel plots and sensitivity analyses. Statistical analysis was performed using STATA version 13.0 software.

RESULTS

A total of 53 studies having 5186 HS and 7347 healthy control subjects were included in our meta-analysis. Pooled analyses showed that ACE I/D gene polymorphism had significant association with risk of HS in overall study population [(dominant model: OR = 1.29, 95% CI = 1.12-1.50 & recessive model: OR = 1.79, 95% CI = 1.46-2.20)]. Population subgroup analyses further revealed significant relationship of ACE I/D polymorphism with ICH in Asians (recessive: OR 1.97, 95% CI = 1.57-2.47) but not in Caucasians (recessive: OR 1.02, 95% CI = 0.76-1.36).

CONCLUSION

This meta-analysis suggests that ACE I/D polymorphism may lead to risk of HS and can be a potential biomarker for HS susceptibility especially in Asian population.

Efficacy of various treatment modalities for nCOV-2019: A systematic review and meta-analysis

BACKGROUND

Several therapeutic agents have been investigated for treatment of novel coronavirus 2019 (nCOV-2019). We conducted a systematic review and meta-analysis to assess the efficacy of various treatment modalities in nCOV-2019 patients.

METHODS

A literature search was conducted before 29 June 2020 in PubMed, Google Scholar and Cochrane library databases. A fixed-effect model was applied if I²  < 50%, else results were combined using random-effect model. Risk ratio (RR) or standardized mean difference (SMD) along with 95% confidence interval (95% CI) was used to pool the results. Between-study heterogeneity was explored using influence and sensitivity analyses, and publication bias was assessed using funnel plots. Entire statistical analysis was conducted in R version 3.6.2.

RESULTS

Fifty studies involving 15 in vitro and 35 clinical studies including 9170 nCOV-2019 patients were included. Lopinavir-ritonavir was significantly associated with shorter mean time to clinical recovery (SMD -0.32; 95% CI -0.57 to -0.06), remdesivir was significantly associated with better overall clinical recovery (RR 1.17; 95% CI 1.07 to 1.29), and tocilizumab was associated with less all-cause mortality (RR 0.38; 95% CI 0.16 to 0.93). Hydroxychloroquine was associated with longer time to clinical recovery and less overall clinical recovery. It additionally had higher all-cause mortality and more total adverse events.

CONCLUSION

Our meta-analysis suggests that except in vitro studies, no treatment has shown overall favourable outcomes in nCOV-2019 patients. Lopinavir-ritonavir, remdesivir and tocilizumab may have some benefits, while hydroxychloroquine administration may cause harm in nCOV-2019 patients. Results from upcoming large clinical trials may further clarify role of these drugs.

CIMT as a risk factor for stroke subtype: A systematic review

INTRODUCTION

An increase in the common carotid artery intima-media thickness (CCA-IMT) is generally considered an early marker of atherosclerosis and is a well-established predictor of cardiovascular disease (CVD). An association between changes in CCA-IMT and risk of stroke has been reported but has conflicting findings.

OBJECTIVE

The present meta-analysis was aimed to clarify the association between CCA-IMT with the risk of stroke and its subtype by estimating pooled analysis of published literature.

METHODS

Comprehensive search for all published articles was performed in electronic databases including PubMed, Embase, Cochrane Library, Trip Databases, Worldwide Science, CINAHL and Google Scholar from 01 January 1950 to 30 April 2020.

RESULTS

In our meta-analysis, a total of 19 studies, of which sixteen studies involving 3475 ischaemic stroke (IS) cases and 11 826 controls; six studies with 902 large vessel disease (LVD) and 548 small vessel disease (SVD) of IS subtypes; five studies with 228 intracerebral haemorrhage (ICH) and 1032 IS cases, were included. Our findings suggest a strong association between increased CCA-IMT with risk of IS as compared to control subjects [SMD = 1.46, 95% CI = 0.90-2.02]. However, there is an increased risk of LVD as compared to the SVD subtype of IS [SMD = 0.36, 95% CI = 0.19-0.52] and more chance of occurrence of IS rather than ICH [SMD = 0.71, 95% CI = 0.28-1.41].

CONCLUSIONS

Carotid intima thickness measurements are found to be associated with the risk of stroke along with its subtypes and may be used as a diagnostic marker for predicting the risk of stroke events.

Global impact of environmental temperature and BCG vaccination coverage on the transmissibility and fatality rate of COVID-19

The 2019-Coronavirus (COVID-19) pandemic has had a global impact. The effect of environmental temperature on transmissibility and fatality rate of COVID-19 and protective efficacy of Bacillus Calmette-Guérin (BCG) vaccination towards COVID-19 remains ambiguous. Therefore, we explored the global impact of environmental temperature and neonatal BCG vaccination coverage on transmissibility and fatality rate of COVID-19. The COVID-19 data for reported cases, deaths and global temperature were collected from 31^st December 2020 to 3^rd April 2020 for 67 countries. Temperature data were split into quartiles for all three categories (minimum temperature, maximum temperature and mean temperature). The impact of three types of temperature data and policy of BCG vaccination on COVID-19 infection was determined by applying the multivariable two-level negative binomial regression analysis keeping daily new cases and daily mortality as outcome. The highest number of cases fell in the temperature categories as following: mean temperature in the second quartile (6°C to 10.5°C), median 26, interquartile range (IQR) 237; minimum temperature in the first quartile (-26°C to 1°C), median 23, IQR 173; maximum temperature in the second quartile (10°C to 16°C), median 27.5, IQR 219. For the minimum temperature category, 28% statistically significant lower incidence was noted for new cases from the countries falling in the second quartile (2°C to 6°C) compared with countries falling in the first quartile (-26°C to 1°C) (incidence rate ratio [IRR] 0.72, 95% confidence interval [CI] 0.57 to 0.93). However, no statistically significant difference in incidence rate was observed for mean temperature categories in comparison to the first quartile. Countries with BCG vaccination policy had 58% less mortality as compared with countries without BCG coverage (IRR 0.42; 95% CI 0.18 to 0.95). Our exploratory study provides evidence that high temperature might not be associated with low transmissibility and countries having neonatal BCG vaccination policy had a low fatality rate of COVID-19.

Blood biomarkers for the diagnosis and differentiation of stroke: A systematic review and meta-analysis

Background

Correct diagnosis of stroke and its subtypes is pivotal in early stages for optimum treatment.

Aims

The aim of this systematic review and meta-analysis is to summarize the published evidence on the potential of blood biomarkers in the diagnosis and differentiation of stroke subtypes.

Methods

A literature search was conducted for papers published until 20 April 2020 in PubMed, EMBASE, Cochrane Library, TRIP, and Google Scholar databases to search for eligible studies investigating the role of blood biomarkers in diagnosing stroke. Quality assessment was done using modified Quality Assessment of Diagnostic Accuracy Studies questionnaire. Pooled standardized mean difference and 95% confidence intervals were calculated. Presence of heterogeneity among the included studies was investigated using the Cochran's Q statistic and I2 metric tests. If I2 was < 50% then a fixed-effect model was applied else a random-effect model was applied. Risk of bias was assessed using funnel plots and between-study heterogeneity was assessed using meta-regression and sensitivity analyses. Entire statistical analysis was conducted in STATA version 13.0.

Results

A total of 40 studies including patients with 5001 ischemic strokes, 756 intracerebral hemorrhage, 554 stroke mimics, and 1774 healthy control subjects analyzing 25 biomarkers (within 24 h after symptoms onset/after the event) were included in our meta-analysis; 67.5% of studies had moderate evidence of quality. Brain natriuretic peptide, matrix metalloproteinase-9, and D-dimer significantly differentiated ischemic stroke from intracerebral hemorrhage, stroke mimics, and health control subjects ( p < 0.05). Glial fibrillary acidic protein successfully differentiated ischemic stroke from intracerebral hemorrhage (standardized mean difference −1.04; 95% confidence interval −1.46 to −0.63) within 6 h. No studies were found to conduct a meta-analysis of blood biomarkers differentiating transient ischemic attack from healthy controls and stroke mimics.

Conclusion

This meta-analysis highlights the potential of brain natriuretic peptide, matrix metalloproteinase-9, D-dimer, and glial fibrillary acidic protein as diagnostic biomarkers for stroke within 24 h. Results of our meta-analysis might serve as a platform for conducting further targeted proteomics studies and phase-III clinical trials. PROSPERO Registration ID: CRD42019139659.

Relationship between methylenetetrahydrofolate reductase (MTHFR) gene (A1298C) polymorphism with the risk of stroke: A systematic review and meta-analysis

Studies on relationship between methylenetetrahydrofolate reductase gene (MTHFR) gene A1298C polymorphism with the risk of ischemic as well as hemorrhagic stroke have shown discordant results. Present meta-analysis was aimed to clarify the relationship between MTHFR gene A1298C polymorphism with risk of stroke. A comprehensive literature search for all published articles was performed in electronic database including PubMed, EMbase, Cochrane Library, Trip Databases, Worldwide Science, CINAHL, and Google Scholar up to 31st  December 2019. Pooled odds ratio (ORs) with 95% confidence interval (CIs) under dominant, recessive, and allelic models was calculated. Sensitivity analysis was also performed to detect the heterogeneity. In our meta-analysis, a total of 20 studies with 19 case control studies involving 2871 ischemic stroke (IS) cases and 3984 controls and 3 studies with 201 hemorrhagic stroke cases and 1349 controls were included. Our findings suggest that there was a significant relationship between MTHFR gene A1298C gene polymorphism with risk of ischemic stroke (dominant model: OR = 1.32, 95% CI = 1.06-1.66, recessive model: OR = 1.45, 95% CI = 1.06-1.99 and allelic model: OR = 1.35, 95% CI = 1.00-1.84, respectively). However, no significant relationship between MTHFR gene A1298C gene polymorphism with the risk of hemorrhagic stroke. Findings of this meta-analysis concludes that MTHFR gene A1298 C polymorphism could be capable of increasing stroke susceptibility in Asian, but not in Caucasian population. Genotyping of MTHFR gene A1298C polymorphism may be used as a predictor for the occurrence of ischemic stroke.

In-Silico structural analysis of wild-type human hemoglobin and its mutation resulting in sickle cell anemia

Background: Hemoglobin (HbA) is a metalloprotein having a heme prosthetic group, two α-globin chains, and two β-globin chains. A point mutation in the 6th position of wild-type HBB gene (GAG>GTG) substitutes Glutamic acid (E) to Valine (V) in the β-chains of hemoglobin molecule (HbS) resulting in Sickle Cell Anemia. Structural deformities in the β-globin gene leads to disruptive conformation of red blood cells, disturbs the oxygen transportation and causes functional abnormalities. Aims and Objective: The purpose of the study was to understand the structural, genetic and metabolic effect of the point mutation on HBB gene that causes sickle cell disease. Materials and Methods: The 3D structures of HbA and HbS proteins were retrieved from PDB and the changes in their physical properties were analyzed using Swiss PDB viewer and Molegro molecule viewer. Gene networks were constructed using GeneMANIA server to study genetic and metabolic interactions of the HBB gene. Results: In-silico studies showed that the normal bond length between Glu6-Glu7 in HbA molecule is 1.32Å and that of HbS is 1.33Å. After comparing the two proteins, it was observed that sickle cell hemoglobin suffers a change in bond angle from 122.4º in HbA to 119.35º in HbS. Comparative energy minimization of Glu6 and Val6 in wild-type and mutant hemoglobin respectively yielded 8.78 and -9.083 KJ/mol net energy values, suggesting a more reactive HbA and less reactive HbS. Gene networks were determined on the basis of physical, genetic and co-expressive interactions of HBB gene which revealed a strong connection between HBB and HBA1 genes within the association constituted of various metabolic functions. Conclusion: Sickle cell disease results from a sequence of events which start with a single nucleotide substitution that ultimately leads to severe anemia and other cardiovascular problems. Incorporation of computational exercises correlates to a better probability of discovering precision medicine through target site-specific drug designing.

Randomized trial of red cell washing for the prevention of transfusion-associated organ injury in cardiac surgery

Background. Experimental studies suggest that mechanical cell washing to remove pro-inflammatory components that accumulate in the supernatant of stored donor red blood cells (RBCs) might reduce inflammation and organ injury in transfused patients.

Methods. Cardiac surgery patients at increased risk of large-volume RBC transfusion were eligible. Participants were randomized to receive either mechanically washed allogenic RBCs or standard care RBCs. The primary outcome was serum interleukin-8 measured at baseline and at four postsurgery time points. A mechanism substudy evaluated the effects of washing on stored RBCs in vitro and on markers of platelet, leucocyte, and endothelial activation in trial subjects.

Results. Sixty adult cardiac surgery patients at three UK cardiac centres were enrolled between September 2013 and March 2015. Subjects received a median of 3.5 (interquartile range 2–5.5) RBC units, stored for a mean of 21 (sd 5.2) days, within 48 h of surgery. Mechanical washing reduced concentrations of RBC-derived microvesicles but increased cell-free haemoglobin concentrations in RBC supernatant relative to standard care RBC supernatant. There was no difference between groups with respect to perioperative serum interleukin-8 values [adjusted mean difference 0.239 (95% confidence intervals −0.231, 0.709), P=0.318] or concentrations of plasma RBC microvesicles, platelet and leucocyte activation, plasma cell-free haemoglobin, endothelial activation, or biomarkers of heart, lung, or kidney injury.

Conclusions. These results do not support a hypothesis that allogenic red blood cell washing has clinical benefits in cardiac surgery.

Clinical trial registration. ISRCTN 27076315.

Knowledge, Attitude and Practice Regarding Environmental Tobacco Smoke among Pregnant Women of Sunsari

Background Second hand tobacco smoke or Environmental Tobacco Smoke (ETS), contains toxic substances and carcinogens that cause serious health effects in humans. Studies show that ETS exposure during pregnancy is injurious to the mother-infant pair with long term consequences. Limited studies are found in context of ETS in pregnancy in Nepal. Objective To explore the knowledge about harmful effect of ETS exposure in pregnant women and to know the behavior of avoidance from exposure to ETS during pregnancy. Method A cross sectional study was conducted among 303 pregnant women attending antenatal clinics at the District Hospital Inaruwa and BPKIHS Dharan. A pre-tested semi-structured questionnaire was used to collect data regarding socio-demographic characteristics, knowledge, attitude and practice regarding Environmental tobacco smoke. Data was entered in Excel and analyzed in SPSS 11.5. Result The mean age of the respondents was 23.86±4.68 years. The proportion of primigravida was 53.5% and multi-gravida was 46.5%. Among the respondents, 14% were illiterate and 91% were unemployed. A similar proportion of the husbands (12%) were illiterate. Three-fourth (75%) of the respondents lived in joint family. It was found that 86% of their husbands were smokers. There were 61% of pregnant women who had heard about ETS, mainly through television (35%) and radio (30%). There was 86% of the households who had initiated some measures to prevent smoking inside the house. Conclusion The pregnant women in this study are aware about ETS. However a significant number of them believe that ETS is not harmful compared to active smoking. There is a need for further studies to identify interventions to avoid ETS exposure among the pregnant women.

Detection of Focal Longitudinal Changes in the Brain by Subtraction of MR Images

BACKGROUND AND PURPOSE

The detection of new subtle brain pathology on MR imaging is a time-consuming and error-prone task for the radiologist. This article introduces and evaluates an image-registration and subtraction method for highlighting small changes in the brain with a view to minimizing the risk of missed pathology and reducing fatigue.

MATERIALS AND METHODS

We present a fully automated algorithm for highlighting subtle changes between multiple serially acquired brain MR images with a novel approach to registration and MR imaging bias field correction. The method was evaluated for the detection of new lesions in 77 patients undergoing cardiac surgery, by using pairs of fluid-attenuated inversion recovery MR images acquired 1-2 weeks before the operation and 6-8 weeks postoperatively. Three radiologists reviewed the images.

RESULTS

On the basis of qualitative comparison of pre- and postsurgery FLAIR images, radiologists identified 37 new ischemic lesions in 22 patients. When these images were accompanied by a subtraction image, 46 new ischemic lesions were identified in 26 patients. After we accounted for interpatient and interradiologist variability using a multilevel statistical model, the likelihood of detecting a lesion was 2.59 (95% CI, 1.18-5.67) times greater when aided by the subtraction algorithm (P = .017). Radiologists also reviewed the images significantly faster (P < .001) by using the subtraction image (mean, 42 seconds; 95% CI, 29-60 seconds) than through qualitative assessment alone (mean, 66 seconds; 95% CI, 46-96 seconds).

CONCLUSIONS

Use of this new subtraction algorithm would result in considerable savings in the time required to review images and in improved sensitivity to subtle focal pathology.

Late production of CXCL8 in ruminant oro-nasal turbinate cells in response to Chlamydia abortus infection

Chlamydia abortus is an obligate intracellular bacterium that is an important cause of ovine abortion worldwide. There are reports of abortions in cattle, but these are very rare compared to the reported incidence in sheep. The bacterium is transmitted oro-nasally and can establish a sub-clinical infection until pregnancy, when it can invade the placenta and induce an inflammatory cascade leading to placentitis and abortion. Early host-pathogen interactions could explain differential pathogenesis and subsequent disease outcome in ruminant species. In this study, we assessed the ability of sheep and cattle oro-nasal turbinate cells to sense and respond to C. abortus infection. The cells expressed toll like receptor (TLR) 2, TLR4, nucleotide oligomerization domain (NOD) 1 and NOD-like receptor pyrin domain containing 3 (NLRP3) mRNA. In response to C. abortus infection, both ovine and bovine turbinate cells produce CXCL8 mRNA and protein late in the bacterial developmental cycle, but do not produce IL-1β or TNF-α. The UV-inactivated bacteria did not elicit a CXCL8 response, suggesting that intracellular multiplication of the bacteria is important for activating the signalling pathways. The production of innate immune cytokines from cattle and sheep turbinate cells in response to C. abortus infection was found to be largely similar.

Regulatory and effector T cells changes in remission and resistant state of childhood nephrotic syndrome

Idiopathic minimal change disease is a disorder of T-cell dysfunction. The relative predominance of regulatory T cells (Tregs), Th1, and Th2 cells in nephrotic syndrome (NS) remains controversial. Imbalance in peripheral blood regulatory and effector T cells (Teff) are linked to cell mediated immune response and may be associated with steroid response in NS. Peripheral blood CD4 + CD25 + FoxP3 + (Tregs), CD4 + IFN-γ⁺ (Th1), and CD4 + IL-4 + (Th2) lymphocytes were analyzed in 22 steroid-sensitive NS (SSNS) patients in sustained remission, 21 steroid-resistant NS (SRNS) and 14 healthy controls. The absolute percentage values and ratio of Th1/Tregs, Th2/Tregs, and Th1/Th2 were compared between SSNS, SRNS and control subjects. The percentage of Tregs was lower in SRNS patients (P = 0.001) compared with that of SSNS and healthy control. The percentage of Th1 cells was higher in SRNS (P = 0.001) compared to that of SSNS patients; however, it was similar to healthy controls (P = 1.00). The percentage of Th2 cells in SRNS (P = 0.001) was higher as compared to SSNS and controls. The ratio of Th1/Treg cells in SRNS (P = 0.001) was higher as compared to SSNS patients and controls. The ratio of Th2/Treg was also higher in SRNS as compared to SSNS and controls. The ratio of Th1/Th2 cells in SSNS, SRNS, and healthy controls were similar. The cytokines secretion complemented the change in different T-cell subtypes in SSNS, SRNS and healthy controls. However, the IFN-γ secretion in healthy controles was low inspite of similar percentage of Th1 cells among SRNS cases. We conclude that greater ratio of Tregs compared to that Th1 and Th2 favor steroid sensitivity and reverse ratio results in to SRNS. The difference in ratio is related to pathogenesis or it can be used as marker to predict steroid responsiveness needs further evaluation.

Differential expression of inducible nitric oxide synthase and cytokine mRNA in chicken lines divergent for cutaneous hypersensitivity response

Phytohemagglutinin (PHA)-induced delayed-type hypersensitivity is an immunocompetent trait considered an indicator of cell-mediated immune or T-cell responses. Divergent selection was performed to generate high and low lines for response to PHA-P. Extreme-responder birds of the F2 generation in each line were used to study possible differences in macrophage activity and the associated functional genes. To evaluate macrophage activity, nitric oxide (NO) was estimated both systemically in serum and in in vitro monocyte culture. Semi-quantitative RT-PCR was used to detect the differential mRNA expression patterns of iNOS and MIP-1beta in monocyte culture, whereas T(H)1 cytokines (IL-2 and IFN-gamma) were studied in peripheral blood mononuclear cells (PBMC) at different time intervals after lipopolysaccharide (LPS) induction. The high line showed strong systemic, as well as in vitro NO production, compared to the low line, upon stimulation with NDV and LPS, similar to early and high iNOS mRNA expression. Following the pattern of iNOS gene expression, an early strong expression of cytokines with powerful iNOS-inducing action, such as IFN-gamma and the chemokine MIP-1beta, was observed in the high line. In contrast, for response to PHA-P, low expression of IL-2 was observed in the high compared to the low line. In conclusion, the study revealed that divergent selection for response to PHA-P resulted in a divergent effect on T(H)1 cell activity, resulting in altered macrophage function in chickens. Selection, based on response to PHA-P, could lead to more resistant birds or birds with an enhanced immune response.

Identifying critical parameters in the dynamics and control of microparasite infection using a stochastic epidemiological model

A stochastic epidemic model is presented to study infection transmission dynamics, and hence epidemic severity and disease incidence, in a closed population. The aim was to understand the relative importance of various parameters that influence the dynamics of potential epidemics, particularly when the genetic mechanisms of resistance or tolerance to infection are considered. Simulations explored the effect of varying the transmission coefficient, latent period, recovery period, mortality rate, and the period of loss of immunity on overall epidemic outcomes. The critical parameters influencing the transmission of infection, and hence disease incidence, were the transmission coefficient, the latent period, and the recovery period; the period of loss of immunity had only trivial effects. Ideally, control strategies should decrease the transmission coefficient and/or increase the latent period and/or decrease the recovery period. By equating measured traits with disease transmission parameters, the model described in this paper can be used to identify which disease resistance genes or QTL will be truly effective in helping to develop disease-resistant livestock that suffer fewer epidemics and side-effects of infection. In particular, emphases should be placed on finding genes that decrease the transmission of infection, increase the latent period, or decrease the recovery period.

Synthesis and antiviral activity of novel acyclic nucleoside analogues of 5-(1-azido-2-haloethyl)uracils

We present the discovery of a novel category of 5-substituted acyclic pyrimidine nucleosides as potent antiviral agents. A series of 1-[(2-hydroxyethoxy)methyl] (5-7), 1-[(2-hydroxy-1-(hydroxymethyl)ethoxy)methyl] (8-10), and 1-[4-hydroxy-3-(hydroxymethyl)-1-butyl] (11-13) derivatives of 5-(1-azido-2-haloethyl)uracil were synthesized and evaluated for their biological activity in cell culture. 1-[4-Hydroxy-3-(hydroxymethyl)-1-butyl]-5-(1-azido-2-chloroethyl)uracil (12) was the most effective antiviral agent in the in vitro assays against DHBV (EC(50) = 0.31-1.55 microM) and HCMV (EC(50) = 3.1 microM). None of the compounds investigated showed any detectable toxicity to several stationary and proliferating host cells.

MoSe2 and WSe2 nanotubes and related structures

MoSe2 and WSe2 nanotubes are obtained by the reduction of the corresponding triselenides in hydrogen or by the decomposition of the ammonium selenometallates in a hydrogen atmosphere.

The ability of helical CT to preoperatively stage endometrial carcinoma

OBJECTIVE

This study evaluated helical CT as an imaging modality for preoperative staging of endometrial carcinoma.

MATERIALS AND METHODS

Three radiologists retrospectively and independently reviewed the preoperative helical CT scans of 25 consecutive patients with endometrial carcinoma. The presence or absence of deep myometrial invasion and the presence or absence of cervical involvement were evaluated on helical CT and compared with pathologic findings at hysterectomy.

RESULTS

Helical CT has a sensitivity of 83% and a specificity of 42% for the detection of deep myometrial invasion (stage IC). Helical CT has a sensitivity of 25% and a specificity of 70% for the detection of cervical involvement (state II). These results compare poorly with those of MR imaging (sensitivity 92%, specificity 90% for the detection of deep myometrial invasion; sensitivity 86%, specificity 97% for the detection of cervical involvement).

CONCLUSION

Helical CT is insensitive and nonspecific compared with MR imaging for the preoperative staging of endometrial carcinoma. MR imaging remains the imaging modality of choice.

Cytomorphologic features of classic and variant lobular carcinoma: A comparative study

There are several subtypes of lobular carcinoma (LC), and their cytomorphologic features differ from classic lobular carcinoma (CLC). The finer details of the differences between CLC and variant lobular carcinoma (VLC) have not been adequately studied. A comparative study of 54 cases of CLC and VLC was done in order to verify any statistically significant differences between them. All cases had histologic confirmation of the diagnosis. Six parameters, which included cellularity, signet-ring cells, intracytoplasmic lumina (ICL), anisonucleosis, cell size, and prominent nucleoli, were studied. The only statistically significant findings were cellularity and cell size when compared to CLC. The cellularity in VLC was higher and the cells in VLC were larger when compared to CLC. There are no definite diagnostic features to identify VLC; however, in a cellular specimen with plenty of large cells with other features of LC, one should have a high index of suspicion of VLC.

Clinical profile of stroke in relation to glycaemic status of patients

Present study was undertaken in fifty consecutive patients of acute stroke to assess the role of glycemic status on clinical profile of stroke. Majority of patients (76%) were in age group of 41-70 years. The patients were classified into four groups: euglycemics (33), known diabetics (8), newly diagnosed diabetics (6) and stress hyperglycemics (3). Diabetics as well as stress hyperglycemics had higher prevalence of larger sized severe haemorrhagic stroke with poor outcome and there was positive correlation between them.

Metabolic studies in congenital vitamin D deficiency rickets

Congenital rickets in 3 newborns of mothers with advanced nutritional osteomalacia, healed with maternal breast milk feeding when mothers alone were given calcium supplements and 7.5 mg of intravenous D2 and the mother baby pair protected from sunlight. Maternal plasma biochemistry indicated more severe vitamin D deficiency compared to their newborns (intrauterine foetal priority). The first dose of 7.5 mg of vitamin D3 and calcium supplements to mother healed osteomalacia but did not appear to heal the rickets of their breast fed infants (extrauterine maternal priority for vitamin D). A second dose given at 3 months interval healed the rickets in their infants and the biochemistry of the mother and baby returned towards normal. Congenital rickets developed when maternal bone mineral and vitamin D stores had been completely exhausted. Raised IPTH levels in the newborn suggested that foetal parathyroids were responsive to hypocalcaemic stimulus.