76 research outputs found

    Relative Contribution of Different Upper Glycolytic Components in the Maintenance of the Retinal Vascular Endothelial Cell Barrier

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    Introduction: Damage to the retinal vascular endothelium is implicated in the progression of retinal degenerative diseases, including diabetic retinopathy (DR) and diabetic macular edema (DME). The retinal endothelial cells constitute the inner blood-retinal barrier (iBRB), and disruption of this barrier allows for the dysregulation of fluid and solute passage into the retina. Moreover, under normal physiological conditions, glycolytic metabolism is critical to the functioning of endothelial cells and maintenance of the iBRB. Conversely, in hyperglycemic environments, unregulated glycolytic metabolism leads to a buildup of glycolytic intermediates, which is thought to contribute to disruption of the iBRB and is associated with retinal cell damage and neovascularization. However, the metabolic mechanisms underlying these processes remain unclear. In this study, we looked to further characterize the roles of upper glycolytic enzymes, those involved in the ATP consumption phase of glycolysis, in the maintenance of the iBRB. Methods: Electric cell-substrate impedance sensing (ECIS) technology was used to assess in real-time the role of different glycolytic enzymes in maintaining the barrier functionality of human retinal endothelial cells (HREC). Furthermore, the endothelial cellular viability was assessed through lactate dehydrogenase cytotoxicity assay following 24h, 48h, and 72h time intervals. Results: Inhibition with heptelidic acid (glyceraldehyde-3-phosphate dehydrogenase (GA3PDH) inhibitor) significantly reduced the resistance (R) and thus the integrity of the HREC barrier at concentrations of 1.0 μM and 10 μM. PFK158 (phosphofructokinase-1 (PFK1) inhibitor) also significantly reduced R, but only at a concentration of 10 μM. Similarly, administration of PFK158 reduced HREC viability throughout all three time intervals (24h, 48h, and 72h) at a concentration of 10 μM. However, administration of heptelidic acid showed reduced HREC viability only at the 72h time interval, but also at a concentration of 10 μM. The other inhibitors tested did not demonstrate significant reduction in resistance of the HREC barrier or in cellular viability. Conclusion: Our study demonstrates the differential roles of glycolytic enzymes in maintaining the barrier functionality of HRECs. We specifically showed that the functions of GA3PDH and PFK-1 are the most important components in regulating HREC barrier integrity. These observed differences are significant since they could serve as the basis for future pharmacological and gene expression studies aiming to improve the activity of GA3PDH and PFK1 and thereby provide avenues for therapeutic modalities in endothelial-associated retinal diseases

    Association between blood lead levels and environmental exposure among Saudi schoolchildren in certain districts of Al-Madinah

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    Mohammed Adnan Zolaly1, Manal Ibrahim Hanafi2,3, Nashaat Shawky4, Khalid el-Harbi1, Ahmed M Mohamadin5,61Pediatric Department, 2Family and Community Medicine Department, Medical College, Taibah University, Al-Madinah Al-Munawwarah, Saudi Arabia; 3Community Medicine Department, Faculty of Medicine, Alexandria University, Alexandria, Egypt; 4Ophthalmology Department, Medical College, 5Chemistry for Health Sciences Department, Deanery of Academic Services, Taibah University, Al-Madinah Al-Munawwarah, Saudi Arabia; 6Biochemistry Department, Faculty of Pharmacy, Al-Azhar University, Cairo, EgyptIntroduction: Both occupational and environmental exposures to lead remain a serious problem in many developing and industrializing countries. When humans are exposed to high levels of lead, there is damage to almost all organs and organ systems (most importantly, the central nervous system, kidneys, and blood), which often culminates in death.Objective: To estimate the prevalence of blood lead levels (BLLs) and to identify the sources of environmental exposure and potential risk factors for elevated BLLs among Saudi schoolchildren.Methods: A cross-sectional survey was conducted from March to May 2010. The study population included 557 Saudi school students of both sexes. A multistage random sampling technique was used. Information about socioeconomic status, house and school construction, and parents' education and employment was collected using questionnaires. Lead was analyzed in a blood sample using an atomic absorption technique and hemoglobin was measured using a Sysmex hematological analyzer.Results: The mean BLL was 4.94 ± 3.38 µg/dL (range 0.45–26.3 µg/dL). A total of 19% had BLLs <1.0 µg/dL, 16% had BLLs <2.5 µg/dL, 15% had BLLs <5.0 µg/dL, 20% had BLLs <7.5 µg/dL, 25% had BLLs <10.0 µg/dL, and about 6% had BLLs >10.0 µg/dL. Analysis of odds by controlling all risk factors (adjusted odds ratio [OR]) that affect BLLs (≥10 µg/dL) indicated that using cosmetics (OR = 18.5, confidence interval [CI] = 14.4–19.8), putting colored toys in mouth (OR = 15.7, CI = 3.6–16.2), eating canned food (OR = 9.8, CI = 7.0–10.1), and using newspaper during food preparation (OR = 7.6, CI = 6.3–8.2) are risk factors. There were significant correlations between BLLs and family habits (r = 0.225, P = 0.000), personal habits (r = 0.321, P = 0.000), eating habits (r = 0.128, P = 0.002) and school building characteristics (r = 0.469, P = 0.000). There was a significant correlation between BLLs and anemia in age group 6 < 12 years (P = 0.000) and age group 12 to less than 18 years, among males (P = 0.000) and females (P = 0.041).Conclusion: The BLLs of children are affected by multiple factors. Female students have higher BLLs and lower hemoglobin concentration than males. The possible sources of lead exposure were use of toothpaste, use of kohl, putting colored toys in the mouth, use of both canned food and canned juice, use of lip gloss in females, and different methods of handling newspaper while preparing food.Keywords: blood, lead, exposure, cosmetics, schoolchildren, anemi

    Glycine is Dysregulated in Human Retinal Endothelial Cells and Proliferative Diabetic Retinopathy

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    Introduction: Diabetic retinopathy (DR) is a leading cause of blindness when it progresses to the proliferative diabetic retinopathy (PDR) stage. However, the alterations in amino acid (AA) profiles in PDR are largely unknown. In the present study, we aimed to characterize the AA profiles and identify the enriched pathways that are dysregulated commonly in both patients with PDR and human retinal endothelial cells (HRECs) subjected to the dual effect of high glucose (HG) and hypoxia, which are common risk factors associated with PDR. Methods: HRECs were treated with osmotic control (Mannitol, 25 mM) or high glucose (HG, 25 mM) for 5 days, followed by normoxia or hypoxia (Hyp, 2% O2) for 24 hours. Thereafter, the Liquid Chromatography-Tandem Mass Spectrometry (LC-MS)/MS-based targeted AA platform was used to quantitatively profile the intracellular AAs in HRECs, followed by a pathway enrichment analysis using MetaboAnalyst. In parallel, vitreous humor samples from patients with PDR who had undergone pars plana vitrectomy (PPV) were assessed for their AA profile and compared to the control groups, including patients with diabetes but without clinical evidence of PDR and patients without diabetes. Principal component analysis (PCA) was performed to assess the differences in the AA profiles between these 3 groups of patients, with a false discovery rate (FDR) \u3c 0.2 set as the threshold for significance. Results: An increasing trend in the levels of AA with non-polar, polar, or basic side chains was observed between the Hyp, HG, and HG+Hyp versus (vs.) control groups. Specifically, a significant difference between the HG+Hyp and control groups was observed in the levels of non-essential AAs with aliphatic non-polar side chains. Dissecting this further, there were significantly higher concentrations of glycine in the HG+Hyp treatment relative to the control group. Pathway enrichment analysis revealed significant associations between the HG+Hyp vs. control comparison, all of which were related to glycine metabolism. Importantly, vitreous humor samples demonstrated higher levels of glycine in the PDR group compared to the non-diabetic and diabetics without PDR groups. Furthermore, PCA analysis revealed a clear separation in the principal components between the controls and the PDR group. Conclusion: Our findings show that non-essential AAs with aliphatic non-polar side chains, and more precisely, glycine was significantly elevated in the HRECs treated with HG+Hyp as well as in vitreous humor samples from patients with PDR. These results indicate AAs may be used as potential biomarkers in assessing the development of PDR, which may set the stage for the design of targeted therapies for patients with PDR

    The Role of 3D CT Imaging in the Accurate Diagnosis of Lung Function in Coronavirus Patients

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    Early grading of coronavirus disease 2019 (COVID-19), as well as ventilator support machines, are prime ways to help the world fight this virus and reduce the mortality rate. To reduce the burden on physicians, we developed an automatic Computer-Aided Diagnostic (CAD) system to grade COVID-19 from Computed Tomography (CT) images. This system segments the lung region from chest CT scans using an unsupervised approach based on an appearance model, followed by 3D rotation invariant Markov–Gibbs Random Field (MGRF)-based morphological constraints. This system analyzes the segmented lung and generates precise, analytical imaging markers by estimating the MGRF-based analytical potentials. Three Gibbs energy markers were extracted from each CT scan by tuning the MGRF parameters on each lesion separately. The latter were healthy/mild, moderate, and severe lesions. To represent these markers more reliably, a Cumulative Distribution Function (CDF) was generated, then statistical markers were extracted from it, namely, 10th through 90th CDF percentiles with 10% increments. Subsequently, the three extracted markers were combined together and fed into a backpropagation neural network to make the diagnosis. The developed system was assessed on 76 COVID-19-infected patients using two metrics, namely, accuracy and Kappa. In this paper, the proposed system was trained and tested by three approaches. In the first approach, the MGRF model was trained and tested on the lungs. This approach achieved 95.83% accuracy and 93.39% kappa. In the second approach, we trained the MGRF model on the lesions and tested it on the lungs. This approach achieved 91.67% accuracy and 86.67% kappa. Finally, we trained and tested the MGRF model on lesions. It achieved 100% accuracy and 100% kappa. The results reported in this paper show the ability of the developed system to accurately grade COVID-19 lesions compared to other machine learning classifiers, such as k-Nearest Neighbor (KNN), decision tree, naïve Bayes, and random forest

    Signaling mechanisms of a water soluble curcumin derivative in experimental type 1 diabetes with cardiomyopathy

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    BACKGROUND: Curcumin exhibits anti-diabetic activities, induces heme-oxygenase-1 (HO-1) and is an inhibitor of transcriptional co-activator p300. A novel water soluble curcumin derivative (NCD) has been developed to overcome low invivo bioavailability of curcumin. We evaluated the effect of the NCD on signaling mechanisms involved in cardiomyocyte hypertrophy and studied whether its action is mediated via inducible HO-1. MATERIALS AND METHODS: Rats were divided into controls, controls receiving NCD, diabetic, diabetic receiving NCD, diabetic receiving pure curcumin, diabetic receiving HO inhibitor, zinc protoporphyrin IX (ZnPP IX) and diabetic receiving NCD and ZnPP IX. NCD and curcumin were given orally. After 45 days, cardiac physiologic parameters, plasma glucose, insulin, glycated hemoglobin (GHb), HO-1 gene expression and HO activity in pancreas and cardiac tissues were assessed. Gene expression of p300, atrial natriuretic peptide (ANP) and myocyte enhancer factor 2 (MEF2A and MEF2C) were studied. RESULTS: NCD and curcumin decreased plasma glucose, GHb and increased insulin levels significantly in diabetic rats. This action may be partially mediated by induction of HO-1 gene. HO-1 gene expression and HO activity were significantly increased in diabetic heart and pancreas. Diabetes upregulated the expression of ANP, MEF2A, MEF2C and p300. NCD and curcumin prevented diabetes-induced upregulation of these parameters and improved left ventricular function. The effect of the NCD was better than the same dose of curcumin

    Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

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    BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

    Left Main Coronary Artery Revascularization in Patients with Impaired Renal Function: Percutaneous Coronary Intervention versus Coronary Artery Bypass Grafting

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    Introduction: The evidence about the optimal revascularization strategy in patients with left main coronary artery (LMCA) disease and impaired renal function is limited. Thus, we aimed to compare the outcomes of LMCA disease revascularization (percutaneous coronary intervention [PCI] vs. coronary artery bypass grafting [CABG]) in patients with and without impaired renal function. Methods: This retrospective cohort study included 2,138 patients recruited from 14 centers between 2015 and 2,019. We compared patients with impaired renal function who had PCI (n= 316) to those who had CABG (n = 121) and compared patients with normal renal function who had PCI (n = 906) to those who had CABG (n = 795). The study outcomes were in-hospital and follow-up major adverse cardiovascular and cerebrovascular events (MACCE). Results: Multivariable logistic regression analysis showed that the risk of in-hospital MACCE was significantly higher in CABG compared to PCI in patients with impaired renal function (odds ratio [OR]: 8.13 [95% CI: 4.19–15.76], p < 0.001) and normal renal function (OR: 2.59 [95% CI: 1.79–3.73]; p < 0.001). There were no differences in follow-up MACCE between CABG and PCI in patients with impaired renal function (HR: 1.14 [95% CI: 0.71–1.81], p = 0.585) and normal renal function (HR: 1.12 [0.90–1.39], p = 0.312). Conclusions: PCI could have an advantage over CABG in revascularization of LMCA disease in patients with impaired renal function regarding in-hospital MACCE. The follow-up MACCE was comparable between PCI and CABG in patients with impaired and normal renal function

    Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

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    Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication

    Global economic burden of unmet surgical need for appendicitis

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    Background: There is a substantial gap in provision of adequate surgical care in many low-and middle-income countries. This study aimed to identify the economic burden of unmet surgical need for the common condition of appendicitis. Methods: Data on the incidence of appendicitis from 170 countries and two different approaches were used to estimate numbers of patients who do not receive surgery: as a fixed proportion of the total unmet surgical need per country (approach 1); and based on country income status (approach 2). Indirect costs with current levels of access and local quality, and those if quality were at the standards of high-income countries, were estimated. A human capital approach was applied, focusing on the economic burden resulting from premature death and absenteeism. Results: Excess mortality was 4185 per 100 000 cases of appendicitis using approach 1 and 3448 per 100 000 using approach 2. The economic burden of continuing current levels of access and local quality was US 92492millionusingapproach1and92 492 million using approach 1 and 73 141 million using approach 2. The economic burden of not providing surgical care to the standards of high-income countries was 95004millionusingapproach1and95 004 million using approach 1 and 75 666 million using approach 2. The largest share of these costs resulted from premature death (97.7 per cent) and lack of access (97.0 per cent) in contrast to lack of quality. Conclusion: For a comparatively non-complex emergency condition such as appendicitis, increasing access to care should be prioritized. Although improving quality of care should not be neglected, increasing provision of care at current standards could reduce societal costs substantially
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