Photodegradation of microcystin-LR using visible light-activated C/N-co-modified mesoporous TiO 2 photocatalyst

Microcystin-LR (MC-LR), a potent hepatotoxin produced by the cyanobacteria, is of increasing concern worldwide because of severe and persistent impacts on humans and animals by inhalation and consumption of contaminated waters and food. In this work, MC-LR was removed completely from aqueous solution using visible-light-active C/N-co-modified mesoporous anatase/brookite TiO 2 photocatalyst. The co-modified TiO 2 nanoparticles were synthesized by a one-pot hydrothermal process, and then calcined at different temperatures (300, 400, and 500 °C). All the obtained TiO 2 powders were analyzed by X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscope (TEM), specific surface area (SSA) measurements, ultraviolet-visible diffuse reflectance spectra (UV-vis DRS), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy, and photoluminescence (PL) analysis. It was found that all samples contained mixed-phase TiO 2 (anatase and brookite), and the content of brookite decreased with an increase in calcination temperature, as well as the specific surface area and the content of non-metal elements. The effects of initial pH value, the TiO 2 content, and MC-LR concentration on the photocatalytic activity were also studied. It was found that the photocatalytic activity of the obtained TiO 2 photocatalysts declined with increasing temperature. The complete degradation (100%) of MC-LR (10 mg L -1 ) was observed within 3 h, using as-synthesized co-modified TiO 2 (0.4 g L -1 ) at pH 4 under visible light. Based on the obtained results, the mechanism of MC-LR degradation has been proposed. © 2019 by the authors

A comparative study of microcystin-LR degradation by UV-a, solar and visible light irradiation using bare and C/N/S-modified titania

In an endeavor to tackle environmental problems, the photodegradation of microcystin- LR (MC-LR), one of the most common and toxic cyanotoxins, produced by the cyanobacteria blooms, was examined using nanostructured TiO2 photocatalysts (anatase, brookite, anatase- brookite, and C/N/S co-modified anatase-brookite) under UV-A, solar and visible light irradiation. The tailoring of TiO2 properties to hinder the electron-hole recombination and improve MC-LR adsorption on TiO2 surface was achieved by altering the preparation pH value. The highest photocatalytic efficiency was 97% and 99% with degradation rate of 0.002 mmol L-1 min-1 and 0.0007 mmol L-1 min-1 under UV and solar irradiation, respectively, using a bare TiO2 photocatalyst prepared at pH 10 with anatase to brookite ratio of ca. 1:2.5. However, the bare TiO2 samples were hardly active under visible light irradiation (<25%) due to a large band gap. Upon UV, solar and vis irradiation, the complete MC-LR degradation (100%) was obtained in the presence of C/N/S comodified TiO2 with a degradation rate constant of 0.26 min-1, 0.11 min-1 and 0.04 min-1, respectively. It was proposed that the remarkable activity of co-modified TiO2 might originate from its mixedphase composition, mesoporous structure, and non-metal co-modification

Epidemiology of Lumpy Skin Disease in Egypt between 2006 and 2018

Lumpy Skin Disease (LSD) is a notifiable vector-borne disease transmitted by blood-feeding insects affecting cattle populations. LSD is a severe disease that is leading to economic losses. In this study, we displayed the prevalence of LSD in Egypt through retrospective and survey studies to point out the possible hazards of this serious disease. The 2006–2018 passive surveillance data were obtained from OIE-Wahis. A survey was conducted on 326 cattle, collected from 40 villages in 2017, using a structured questionnaire. Between 2006 and 2018, a total of 577 positive LSD outbreaks were reported. For spatial distribution, the Delta region showed the highest significant prevalence of 88% in the 2006 outbreak. Afterwards, Upper Egypt recorded the highest LSD prevalence between 2014 and 2018. The temporal distribution showed an alternative seasonal prevalence of LSD. In the cross-sectional study, the Delta had the highest prevalence, followed by Upper Egypt. Between the seasons, autumn had the highest prevalence followed by winter. Animals over the age of two years had the highest prevalence of risk factors. Dairy animals had a high significant prevalence. Housing animals in the open, the presence of farms near markets and repeated visits to markets, all had a high prevalence. The abundance of biting-flies significantly increased the prevalence. Almost all of the farmers were significantly unaware of the disease. The absence of periodic cleaning, animal isolation, and proper carcass disposal, all significantly increased LSD prevalence especially in unvaccinated animals. In conclusion, the retrospective and cross-sectional studies showed that LSD is an endemic disease with both spatial and temporal distributions. In addition, the survey pointed out the husbandry and biosecurity breaches that magnify LSD prevalence. Therefore, raising disease awareness and applying strategic prevention and control measures are the practical pillars against LSD

Gut epithelial barrier damage caused by dishwasher detergents and rinse aids

Background: The increased prevalence of many chronic inflammatory diseases linked to gut epithelial barrier leakiness has prompted us to investigate the role of extensive use of dishwasher detergents, among other factors. Objective: We sought to investigate the effects of professional and household dishwashers, and rinse agents, on cytotoxicity, barrier function, transcriptome, and protein expression in gastrointestinal epithelial cells. Methods: Enterocytic liquid-liquid interfaces were established on permeable supports, and direct cellular cytotoxicity, transepithelial electrical resistance, paracellular flux, immunofluorescence staining, RNA-sequencing transcriptome, and targeted proteomics were performed. Results: The observed detergent toxicity was attributed to exposure to rinse aid in a dose-dependent manner up to 1:20,000 v/v dilution. A disrupted epithelial barrier, particularly by rinse aid, was observed in liquid-liquid interface cultures, organoids, and gut-on-a-chip, demonstrating decreased transepithelial electrical resistance, increased paracellular flux, and irregular and heterogeneous tight junction immunostaining. When individual components of the rinse aid were investigated separately, alcohol ethoxylates elicited a strong toxic and barrier-damaging effect. RNA-sequencing transcriptome and proteomics data revealed upregulation in cell death, signaling and communication, development, metabolism, proliferation, and immune and inflammatory responses of epithelial cells. Interestingly, detergent residue from professional dishwashers demonstrated the remnant of a significant amount of cytotoxic and epithelial barrier-damaging rinse aid remaining on washed and ready-to-use dishware. Conclusions: The expression of genes involved in cell survival, epithelial barrier, cytokine signaling, and metabolism was altered by rinse aid in concentrations used in professional dishwashers. The alcohol ethoxylates present in the rinse aid were identified as the culprit component causing the epithelial inflammation and barrier damage. Keywords: Alcohol ethoxylates; Caco-2; cytotoxicity; dishwasher detergents; epithelial barrier; inflammation; rinse aid

Disrupted epithelial permeability as a predictor of severe COVID-19 development

BackgroundAn impaired epithelial barrier integrity in the gastrointestinal tract is important to the pathogenesis of many inflammatory diseases. Accordingly, we assessed the potential of biomarkers of epithelial barrier dysfunction as predictive of severe COVID‐19.MethodsLevels of bacterial DNA and zonulin family peptides (ZFP) as markers of bacterial translocation and intestinal permeability and a total of 180 immune and inflammatory proteins were analyzed from the sera of 328 COVID‐19 patients and 49 healthy controls.ResultsSignificantly high levels of circulating bacterial DNA were detected in severe COVID‐19 cases. In mild COVID‐19 cases, serum bacterial DNA levels were significantly lower than in healthy controls suggesting epithelial barrier tightness as a predictor of a mild disease course. COVID‐19 patients were characterized by significantly elevated levels of circulating ZFP. We identified 36 proteins as potential early biomarkers of COVID‐19, and six of them (AREG, AXIN1, CLEC4C, CXCL10, CXCL11, and TRANCE) correlated strongly with bacterial translocation and can be used to predict and discriminate severe cases from healthy controls and mild cases (area under the curve (AUC): 1 and 0.88, respectively). Proteomic analysis of the serum of 21 patients with moderate disease at admission which progressed to severe disease revealed 10 proteins associated with disease progression and mortality (AUC: 0.88), including CLEC7A, EIF4EBP1, TRANCE, CXCL10, HGF, KRT19, LAMP3, CKAP4, CXADR, and ITGB6.ConclusionOur results demonstrate that biomarkers of intact or defective epithelial barriers are associated with disease severity and can provide early information on the prediction at the time of hospital admission

Safety and efficacy of percutaneous nephrolithotripsy in comorbid patients: A 3 years prospective observational study

Purpose: To report the result of percutaneous nephrolithotripsy (PCNL) via standard nephrostomy tract in a single training institution. The perioperative complications in relation to the comorbid state are particularly assessed. Patients and methods: A prospective interventional study between January 2019 to November 2022, included 210 patients scheduled for PCNL. The average age was 40.3 ± 11.8 years (range 18- 67 years). Patients were categorized into two groups. The first group comprised 146 cases (69 .5%) with no associated co-morbidities while the second group 64 (30.5%) had co-morbidities such as obesity in 4 cases (1.9%), hypertension (HTN) in 24 cases (11.4%) cases, diabetes mellitus (DM) in 17 (8.1%) cases, history of recurrent stone surgery in 11 (5.2%) cases and more than one in 8 cases (3.8%). Co-morbidities, stone burden, location of stone, time of surgery, stay in the hospital, further operations, and negative events were among the reported data. Complications and the stone-free rate were the main outcome indicators. Results: Intraoperative complications were reported in 40 (18.8%) patients (18 group 1 and 22 group 2) during PCNL. Bleeding occurred in 22 (10.5%) patients (9 group 1 and 13 group 2), blood transfusions were needed in 4 (1.9%) (2 group 1 and 2 group 2), extravasation was observed in 11 patients (5.2%) (6 group 1 and 5 group 2) and cardiac arrhythmia in 3 (1.4%) (1 group 1 and 2 group 2) patients. Postoperative complications occurred in 61 patients (29%) (24 group 1 and 37 group 2) in the form of fever in 10 patients (4.8 %) (3 group 1 and 7 group 2) and prolonged leakage in 50 patients (23.8%) (21 group 1 and 29 group 2). One patient of group 2 died from postoperative sepsis. Extravasation and postoperative leakage were higher in diabetic patients than in non-diabetics. Stonefree rate was 60.5% (127 of 210). Clinically significant residual fragments (CSRFs) found in 70 cases (33.3%) (33 group 1 and 37 group 2). In 13 cases (6.2%) (5 group 1 and 8 group 2), clinically insignificant residual fragments (CIRFs) were found. In 8 (3 group 1 and 5 group 2) of the 13 cases, spontaneous stone passage was observed within 4-6 weeks of surgery. Residual stones in three cases (1 group 1 and 2 group 2) were asymptomatic and 4 mm or less, whereas stones increased in two cases of group 2. Among all factors studied, stone burden was significantly correlated to both intraoperative and postoperative complications. The occurrence of postoperative fever increased with large stone burden. Conclusions: PCNL is a therapeutic modality that is effective, feasible, and safe for a wide range of patients with concurrent medical issues. A steep curve is required to reduce intraoperative and postoperative complications