Neutrophil Extracellular Traps Are Induced by Coronavirus 2019 Disease-Positive Patient Plasma and Persist Longitudinally: A Possible Link to Endothelial Dysfunction as Measured by Syndecan-1.

Background: Neutrophil extracellular trap (NET) formation is a mechanism that neutrophils possess to respond to host infection or inflammation. However, dysregulation of NETosis has been implicated in many disease processes. Although the exact mechanisms of their involvement remain largely unknown, this study aimed to elucidate NET formation over the time course of coronavirus disease 2019 (COVID-19) infection and their possible role in endothelial injury. Patients and Methods: Plasma samples from COVID-19-positive patients were obtained at six timepoints during hospitalization. Neutrophils were extracted from healthy donors and treated with COVID-19-positive patient plasma. Myeloperoxidase (MPO) assay was used to assess for NETosis. Syndecan-1 (SDC-1) enzyme-linked immunosorbent assay (ELISA) was run using the same samples. Immunocytochemistry allowed for further quantification of NETosis byproducts MPO and citrullinated histone 3 (CitH3). The receiver operating characteristic (ROC) curve discriminated between admission levels of SDC-1 and MPO in predicting 30-day mortality and need for ventilator support. Results: Sixty-three patients with COVID-19 were analyzed. Myeloperoxidase was upregulated at day 3, 7, and 14 (p = 0.0087, p = 0.0144, p = 0.0421). Syndecan-1 levels were elevated at day 7 and 14 (p = 0.0188, p = 0.0026). Neutrophils treated with day 3, 7, and 14 plasma expressed increased levels of MPO (p < 0.001). Immunocytochemistry showed neutrophils treated with day 3, 7, and 14 plasma expressed higher levels of MPO (p < 0.001) and higher levels of CitH3 when treated with day 7 and 14 plasma (p < 0.01 and p < 0.05). Admission SDC-1 and MPO levels were found to be independent predictors of 30-day mortality and need for ventilator support. Conclusions: Neutrophil dysregulation can be detrimental to the host. Our study shows that COVID-19 plasma induces substantial amounts of NET formation that persists over the course of the disease. Patients also exhibit increased SDC-1 levels that implicate endothelial injury in the pathogenesis of COVID-19 infection. Furthermore, MPO and SDC-1 plasma levels are predictive of poor outcomes.

Salivary Alterations of Myeloperoxidase in Patients with Systemic Diseases: A Systematic Review.

Salivary myeloperoxidase (MPO) is a key mediator of the oral immune system, acting as an enzyme that utilises H2O2 to generate molecules with high bactericidal activity. While MPO determination in plasma is quite common, the use of saliva is still rare. Our systematic review was designed to answer the question "Are salivary levels of myeloperoxidase altered in patients with systemic diseases?". Following the inclusion and exclusion criteria, we included twenty-six studies. Altered MPO levels in saliva were most commonly found in patients with cardiovascular and gastrointestinal diseases. Most studies concerned unstimulated whole saliva, and only a few of them stimulated, mainly by chewing paraffin. Enzyme-linked immunosorbent assay (ELISA) was the most common method for determination of MPO concentrations in saliva. Increased salivary MPO levels were more often observed for inflammatory diseases, except patients with inflammatory bowel diseases who were eligible for biologic therapy. In conclusion, MPO could be altered in the saliva of patients with systematic diseases, especially cardiovascular or gastrointestinal diseases. However, further investigations are recommended to validate these outcomes.

Role of Myeloperoxidase in ROS Generation and Inflammation Response on Prostate Epithelial Cells.

Myeloperoxidase (MPO) has been reported in prostate tissue, and considering its pro-oxidant properties, this location might be linked to prostate pathology. The possibility that the glandular prostatic tissue might be the source of MPO and its potential inflammatory effects must be tested. Human prostate material was obtained from prostate biopsies and radical prostatectomies. Immunohistochemistry was performed using MPO-specific human antibody. In situ hybridization using MPO-specific probes and laser-assisted microdissection for quantitative real-time RT-PCR were performed to observe whether MPO is being produced in prostate tissue. Mass spectrometry on prostate biopsies was used to detect products of MPO activity in nucleic acids (DNA/RNA). MPO contribution to intracellular accumulation of ROS and interleukin-8 in prostatic epithelial cells was monitored in vitro. Immunohistochemistry confirmed cellular localization of MPO in epithelial cells of the prostate. The staining varied from light to high intensity. In situ hybridization did not address the presence of mRNA coding for MPO. No MPO-specific modifications on nucleic acids were detected. Mox-LDL was a major factor inducing ROS and cytokines production in prostatic epithelial cells. We did not demonstrate that MPO was synthetized by prostatic epithelial cells. However, in vitro experiments showed the ability of MPO to potentiate the ROS production and inflammation on prostate epithelial cells. Results do not allow us to demonstrate a role of MPO in prostate to date but further studies are mandatory to focus on the potential impact of MPO in the development of prostatic diseases.

A novel strategy for identification of pesticides in different categories by concentration-independent model based on a nanozyme with multienzyme-like activities.

Conventional rapid detection methods are difficult to identify or distinguish various pesticide residues at the same time. And sensor arrays are also limited by the complexity of preparing multiple receptors and high cost. To address this challenge, a single material with multiple properties is considered. Herein, we first found that different categories of pesticides have diverse regulatory behaviors on the multiple catalytic activities of Asp-Cu nanozyme. Thus, a three-channel sensor array based on the laccase-like, peroxidase-like, and superoxide dismutase-like activities of Asp-Cu nanozyme was constructed and successfully used for the discrimination of eight kinds of pesticides (glyphosate, phosmet, isocarbophos, carbaryl, pentachloronitrobenzene, metsulfuron-methyl, etoxazole, and 2-methyl-4-chlorophenoxyacetic acid). In addition, a concentration-independent model for qualitative identification of pesticides has been established, and 100% correctness was achieved in the recognition of unknown samples. Then, the sensor array also exhibited excellent interference immunity and was reliable for real sample analysis. It provided a reference for pesticide efficient detection and food quality supervision.

Evaluación de un inmunoensayo para la medida de anticuerpos anti-tiroglobulina y anti-tiroperoxidasa / Evaluation of an immunoassay for the antithyroglobulin and antithyroperoxidase measuring

Introducción: La medición de los anticuerpos frente a tiroglobulina (ATG) y peroxidasa tiroidea (ATPO) es de interés para identificar pacientes con tiroiditis autoinmune.Este estudio pretende evaluar un inmunoensayo comercial de electroquimioluminiscencia para ATG y ATPO, estudiando la imprecisión, la linealidad, sensibilidad analítica, evaluación del arrastre, e influencia de interferentes endógenos.Material y métodos: La imprecisión se evaluó usando tres soluciones con diferentes concentraciones de analitos, analizándose 20 veces en la misma serie analítica y durante 20 días consecutivos, calculando el coeficiente de variación. Para el estudio de linealidad se combinaron una muestra con elevada concentración de analitos y un diluyente, obteniéndose concentraciones intermedias que se analizaron por triplicado. El límite de detección se calculó haciendo 20 determinaciones de una muestra de diluyente. El arrastre se evaluó analizando una muestra con alta concentración de anticuerpos seguida por otra con concentraciones muy bajas. El estudio de interferencias se realizó añadiendo a mezclas de suero hemolizado, Intralipid 30% y bilirrubina.Resultados: Las imprecisiones totales obtenidas (%) fueron 26,63, 9,53, y 14,9 para ATG y 21,19, 14,82 y 5,77 para ATPO. La linealidad queda definida por las ecuaciones de regresión: Y=6.61+1.01X(ATG) y Y=16.37+0.97X(ATPO). El límite de detección fue 17,17 para ATG y 5 para ATPO. El arrastre no fue significativo. La hemólisis produjo interferencia significativa en ambos ensayos.Conclusiones: Las imprecisiones obtenidas son comparables a las declaradas por el fabricante. La sensibilidad analítica cumple las especificaciones del fabricante. El comportamiento de ambos ensayos es lineal y no se halla arrastre significativo. La hemólisis interfiere ambos ensayos. (AU)

Introduction: The measuring of antibodies against thyroglobulin (ATG) and thyroperoxydase (ATPO) is useful for identifying patients with autoimmunethyroiditis. This study tries to assess an electrochemiluminescent immunoassay for ATG and ATPO, evaluating imprecision, linearity, analytic sensitivity, carry-over and the influence of endogenous interferents.Material and methods: Imprecision was assessed using three pools with different analytes concentrations, performing within run and between run 20 times. Fort the linearity study a sample containing high analyte concentration and a solvent devoid of analyte were combined, obtaining intermediates concentrations, which were analyzed by triplicate. The limit of detection was calculated analyzing 20 times a sample devoid of analyte. Carry-over was evaluated analyzing a sample with a high antibody concentration followed by other one containing low antibody concentration. The interference study was carried-out adding hemolyzed, Intralipid 30% and bilirubin into sera pool.Results: Total imprecision obtained (%) were 26.63, 9.53, and 14.9 for ATG and 21.19, 14.82, and 5.77 for ATPO. Linearity was defined for the following regression equations: Y=6.61+1.01X (ATG) and, Y=16.37+0.97X (ATPO). The limit of detection was 17.17 for ATG and 5 for ATPO. Carry-over was not significant. Hemolysis caused significant interference in both assays.Conclusions: Imprecision obtained were similar to the manufacturer declared ones. Analytic sensibility complies the manufacturer’s specifications. The behavior of both assays was linear and significant carry-over was not found. Hemolysis interferes in both assays. (AU)

Effect of chemical pretreatment on quality attributes of the cashew apple.

Cashew apples, tropical pseudo fruit, are rich in bioactive compounds. It is still underutilized due to its high perishability and its astringent flavor. This study aims to extend its shelf life by chemical dip and dry method at the rural level. Inhibition of fruit-spoiling enzymes, such as polyphenol oxidase (PPO), peroxidase (POD), amylase, and cellulase, was a significant response in this method. Enzyme inhibition was carried out using chemicals: NaCl (1-10 mM), CaCl2 (1-10 mM), and ethylenediamine tetraacetic acid (0.1-1 mM). The effect of chemical concentration and dipping time was studied using a full factorial method at three levels (-1, 0, and 1). The dipping time ranged from 60 to 180 min, and chemical concentrations from 1 to 10 mM were studied. Optimal treatment conditions were obtained as follows: NaCl concentration of 9.45 mM, dipping time of 160 min, and CaCl2 concentration of 7.8 mM, dipping time of 160 min. NaCl pretreatment showed maximum inhibition of PPO (>80%) and POD (>80%), whereas CaCl2 pretreatment showed maximum inhibition of amylase (60.58%) and cellulase (80.23%). Hence, to avoid postharvest losses, pretreatment with NaCl and CaCl2 was adequate to preserve the texture and color of cashew apples. PRACTICAL APPLICATION: Chemical pretreatment can prevent the postharvest losses of cashew apples. Inhibition of PPO, POD, amylase, and cellulase is vital in the shelf-life extension of cashew apples. Sodium chloride dip is a cost-effective method for increasing the storability of cashew apples.

Acute Promyelocytic Leukemia Suggesting a Diagnosis of Myelodysplastic Syndrome: a Diagnostic Dilemma.

BACKGROUND: Although acute promyelocytic leukemia displays a wide spectrum of morphological variants, the classic morphological variants are defined as hypergranular variants and the hypogranular or microgranular form. METHODS: We report here for the first time a rare morphological variant of APL mimicking myelodysplastic syndrome. A 49-year-old man presented with pancytopenia. Laboratory findings were as follows: White blood cell count was 1.39 x 109/L, hemoglobin was 120 g/L, platelet count was 103 x 109/L, fibrinogen was 3.42 g/L and D-dimer was 3.14 mg/L. Peripheral blood smear revealed no blast or immature cells. Very careful inspection of bone marrow smears indicated 5% blast cells, of which 50% had hyperbasophilic cytoplasm and obvious cytoplasmic blebs mimicking megakaryoblasts or micromegakaryocytes, the others were promyelocytes with obvious bilobed nuclei and fine azurophilic granules. One or a few Auer rods could be seen in 0.5% of the blasts. Myeloperoxidase was strongly positive in the blast cells. Immunophenotyping of the BM revealed an abnormal myeloid population, which was negative for CD34 and HLA-DR. Cytogenetic analysis of the bone marrow cells revealed a 46,XY,t(15;17)(q24;q21)[3]/46,XY[4] karyotype, and the PML-RARA fusion gene was positive. RESULTS: The patient was diagnosed with acute promyelocytic leukemia according to WHO classification. CONCLUSIONS: The patient was initially diagnosed with myelodysplastic syndrome with excess blasts 2 based on cytological features. Due to the need for specific emergency treatment to avoid the risk of potentially fatal bleeding, recognition of the distinctive morphological features is vital for the diagnosis and prognosis of APL.

Assessment of serum and synovial fluid MMP-3 and MPO as biomarkers for psoriatic arthritis and their relation to disease activity indices.

Research on biomarkers for the diagnosis and monitoring of psoriatic arthritis (PsA) is ongoing. The purpose of this study was to assess the potential of serum and synovial fluid matrix metalloproteinase-3 (MMP-3) and myeloperoxidase (MPO) as biomarkers for PsA and their relation to disease activity indices. This case-control study involved 156 psoriatic arthritis patients, 50 gonarthrosis patients, and 30 healthy controls. The target parameters were measured with the enzyme-linked immunosorbent assay (ELISA) kits. Serum MMP-3 and MPO levels were elevated in the PsA patients in comparison to the two control groups (p < 0.001) and distinguished PsA from GoA patients and healthy controls with 100% accuracy. Synovial MMP-3 discriminated PsA from GoA patients irrespective of the presence of crystals (AUC = 1.00). PsA patients with crystals in the synovial fluid had elevated synovial MPO (p < 0.001) and were distinguished from PsA patients without crystals with accuracy of 88.50% and from GoA patients with accuracy of 88.30%. Synovial fluid MPO was positively associated with the following indicators of disease activity: VAS (rs = 0.396); DAPSA (rs = 0.365); mCPDAI (rs = 0.323). Synovial MMP-3 showed a weaker positive association with DAPSA (rs = 0.202) and mCPDAI (rs = 0.223). Our results suggest that serum MMP-3 and MPO could serve as biomarkers for PsA. Synovial fluid MMP-3 showed a potential as a biomarker for PsA versus GoA. Synovial MPO could be utilized as a marker for the presence of crystals in PsA patients.

Fecal biomarkers of environmental enteric dysfunction and associated factors among children aged 24-59 months in east Dembiya district, northwest Ethiopia.

BACKGROUND: Environmental enteric dysfunction is a subclinical intestinal disorder characterized by gut inflammation accompanied by morphological changes, such as blunted villi and crypt hyperplasia. This is a common illness in low and middle-income countries. However, environmental enteric dysfunction evidence is limited in Ethiopia. Accordingly, this study was conducted to measure fecal biomarkers of environmental enteric dysfunction and associated factors among children aged 24-59 months in rural northwest Ethiopia. METHODS: A community-based cross-sectional study was employed among 235 randomly selected children in a rural setting of the east Dembiya district. Stool samples were collected without fixative and analyzed for fecal biomarkers of environmental enteric dysfunction (Alpha-1-antitrypsin, neopterin, and myeloperoxidase) using commercial enzyme-linked immunosorbent assay kits and analyzed for intestinal parasites using wet mount and Kato-Katz techniques. Child behaviors related with exposure to enteropathogens, condition of the living environment and socio-demographic information were collected using interviewer-administered questionnaire and structure observation. We fitted multivariable linear regression model to assess the association between environmental factors and concentration of fecal biomarkers of environmental enteric dysfunction in the stool. Statistically significant associations were declared based on adjusted betas with the corresponding 95% confidence interval and p-value < 0.05. RESULTS: The median concentration of fecal markers of environmental enteric dysfunction was 350 µg/ml for Alpha-1-antitrypsin, 3320.2 ng/ml for myeloperoxidase, and 1562 nmol/l for neopterin. The median concentration of Alpha-1-antitrypsin among 161 (68.5%), myeloperoxidase among 168 (71.5%), and neopterin among 188 (80%) of the stool samples were above the normal values in non-tropical settings. Moreover, 100 (42.6%) of the children had high EED disease activity score (above the median score). The elevated concentrations of fecal biomarkers of gut inflammation and the high EED disease activity score were significantly associated with open defecation practice, mouthing of soil contaminated materials, Escherichia coli (E. coli)  contamination of drinking water, E. coli contamination of foods, E. coli contamination of soil, and intestinal parasites. CONCLUSION: Overall, Alpha-1-antitrypsin, myeloperoxidase, and neopterin levels among the children in the studied region were highly elevated in comparison to populations in high-income countries. Moreover, the EED disease activity score in significant proportion of children was high, suggesting widespread intestinal inflammation and increased intestinal permeability. Extensive E. coli contamination of the living environment (drinking water, ready-to-eat foods, and courtyard soil), hygiene and sanitation behaviors (such as open defecation and mouthing of soil contaminated materials), and a high burden of intestinal parasites were identified as factors associated with the elevated concentration of fecal biomarkers of environmental enteric dysfunction. Parental care to children to avoid mouthing of soil contaminated materials and other risky behaviors that increase exposure enteric infections, and protecting the living environment (water, food and soil) from fecal contamination are important.

Evaluation of UV-B protective properties of leaves and seeds of Achyranthes aspera in Asian catfish Clarias batrachus (Linn.).

The ultraviolet-B (UV-B) radiation is harmful to the aquatic organisms. The UV-B protective properties of leaves and seeds of herb Achyranthes aspera were evaluated in Clarias batrachus. Fish were fed with four diets-EFL1, EFL2 containing 0.25 and 0.5% leaves, EFS containing 0.5% seeds and control, CF. After 83 days of feeding, fish were exposed to UV-B (157 µW/cm2) for 7 days at the rate of 15 min/day. One batch of fish in each treatment was kept unexposed. Significantly higher final weight was found in EFS followed by EFL2 and EFL1 treatments. It was higher in unexposed fish compared to the exposed ones. Among exposed fish, significantly higher lysozyme was found in EFS and myeloperoxidase in EFS and EFL2 compared to others. Nitric oxide synthase and superoxide dismutase levels were significantly higher in liver and head kidney of EFS diet fed fish compared to others. Thiobarbituric acid reactive substances (TBARS) and carbonyl protein levels were minimum in EFS followed by EFL2. The independent sample t-test showed that nitric oxide synthase was significantly higher and myeloperoxidase and TBARS levels were significantly lower in unexposed group compared to the exposed fish in respective treatment. There were up-regulations of TNF-α, iNOS, NF-kB, BAX, Cytochrome c, SOD-c, Caspase 3, Caspase 9, BCL2 in liver and head kidney of leaves and seeds incorporated diets fed fish compared to control. Supplementation of A. aspera seeds and leaves at 0.5% level in diets gave UV-B protection to the fish.

Punicalagin and ellagic acid containing Punica granatum L. fruit rind extract prevents vincristine-induced neuropathic pain in rats: an in silico and in vivo evidence of GABAergic action and cytokine inhibition.

Objectives: We aimed to investigate the protective potential of Punica granatum L. fruit rind extract (PFE) containing punicalagin (10.3% W/W), ellagic acid (EA) (2.7%W/W) in vincristine (75 µg/kg i.p.)- induced neuropathic pain in Wistar rats.Methods: Docking simulation studies were done on the three-dimensional (3D) structure of the GABAA and PPAR γ receptor for the binding of EA as well as punicalagin docking studies on TNF-α, and IL-6. The Present Study conceptualized a test battery to evaluate the behavioral, biochemical and histological changes.Results: Vincristine -induced significant cold allodynia, mechanical hyperalgesia, and functional deficit on 12th and 21st days. It also increased in the levels of TNF-α (Tumor necrosis factor-α), IL-6 (Interleukin-6), and MPO (Myeloperoxidase). Administration of PFE (100 and 300 mg/kg, p.o.), EA (50 mg/kg), and gabapentin (100 mg/kg) attenuated Vincristine-induced behavioral and biochemical changes significantly (P < .05). PFE showed better antinociceptive activity to EA. The histopathological evaluation also revealed the protective effects of PFE. Pretreatment of bicuculline (selective antagonist of GABAA receptors) reversed antinociceptive action of PFE, but administration of γ aminobutyric acid potentiated the action of PFE. PPAR-γ antagonist BADGE did not modify the effect of PFE. Docking results revealed that EA properly positioned into GABA and PPARγ binding site and acts as a partial agonist. Docking score of Punicalagin found to be - 9.02 kcal/mol and - 8.32 kcal/mol on IL-6 and TNFα respectively.Discussion: Conclusively, the attenuating effect of PFE may be attributed to the GABAergic system, cytokine inhibition, and anti-inflammatory activities.

Generation of neutrophil extracellular traps in patients with acute liver failure is associated with poor outcome.

BACKGROUND AND AIMS: Acute liver failure (ALF) is characterized by significant changes in the hemostatic system and by systemic inflammation. The formation of neutrophil extracellular traps (NETs), in which an activated neutrophil expels its DNA, histones, and granular enzymes, such as myeloperoxidase (MPO), has been associated with immune-mediated and thrombotic diseases. We hypothesized that formation of NETs in patients with ALF contributes to progression of disease. APPROACH AND RESULTS: A total of 676 patients with ALF (international normalized ratio [INR], ≥1.5) or severe acute liver injury (ALI; INR, ≥2.0) were recruited from the U.S. ALF Study Group Registry between 2011 and 2018, of whom 308 patients (45.6%) had acetaminophen-induced ALF. Up to 21 days after admission, 483 patients (71.5%) survived without liver transplantation (LT). Levels of cell-free DNA (cfDNA) and the specific NET marker MPO-DNA complexes were measured in plasma samples obtained on admission and compared to levels in healthy controls. In addition, liver tissue obtained at transplantation of 20 ALF patients was stained for NETs. Levels of cfDNA were 7.1-fold, and MPO-DNA complexes 2.5-fold, higher in patients with ALF compared to healthy controls. cfDNA levels were not associated with 21-day transplant-free survival, but were higher in those patients with more-severe disease on admission, as reflected by various laboratory and clinical parameters. MPO-DNA levels were 30% higher in patients with ALF who died or required urgent LT. Liver tissue of ALF patients stained positive for NETs in 12 of 18 evaluable patients. CONCLUSIONS: Here, we provide evidence for NET formation in patients with ALF. Elevated plasma levels of MPO-DNA complexes in patients with ALF were associated with poor outcome, which suggests that NET formation contributes to disease progression.

Effects of Urtica dioica Seeds on Oxidative/ Nitrosative Stress Levels and Myeloperoxidase Activity in Muscle Ischemia/Reperfusion Injury

Abstract The purpose of this study is to evaluate the preventive effects of Urtica dioica (UD) on muscle ischemia/reperfusion (I/R) injury. A total of 27 male Wistar rats were divided into three groups as the control group (1), I/R + saline group (2), and I/R+UD group (3). Group 1 did not receive any treatment. Group 2 was administered a total of 2mL/kg saline (1mL/kg before ischemia and 1 mL/kg after reperfusion), and group 3 was given a total of 2mL of UD (1mL/kg before ischemia and 1mL/kg after reperfusion) as treatment. Saline and UD were administered via intraesophageal canula once a day for five days. At the end of five days, all the rats were exposed to muscle ischemia for 60 min followed by 60 min of reperfusion of the bilateral hindlimbs induced using a tourniquet. Muscle tissue histopathologies were evaluated by light microscopy. Furthermore, oxidative/nitrosative stress biomarkers such as catalase (CAT), superoxide dismutase (SOD), malondialdehyde (MDA), nitrotyrosine (3-NT), nitric oxide (NO), and myeloperoxidase (MPO) as an inflammatory marker in tissue samples were measured. UD treatment significantly decreased oxidative/nitrosative stress biomarker levels and MPO (p<0.05). We established that UD treatment could alleviate muscle injury induced by muscle I/R in rats by inhibiting the inflammation and oxidative/nitrosative stress

Improvement of Cutaneous Wound Healing via Topical Application of Heat-Killed Lactococcus chungangensis CAU 1447 on Diabetic Mice.

Cutaneous wound healing comprises a complex systemic network. Probiotics, naturally extracted substances, medicine, and chemical compounds have been used for wound healing, but the application of postbiotics as therapeutic agents has yet to be explored. Our study shows potential beneficial effects of heat-killed Lactococcus chungangensis CAU 1447 on type 1 diabetic mice. The postbiotic strain significantly decreased the skin wound size. The activity of myeloperoxidase secreted from neutrophils also decreased. The molecular mechanism of wound healing was adjusted by important mediators, growth factors, chemokines, and cytokines. These elements regulated the anti-inflammatory activity and accelerated wound healing. To determine the role of the postbiotic in wound repair, we showed a similar taxonomic pattern as compared to the diabetic mice using skin microbiome analysis. These findings demonstrated that heat-killed Lactococcus chungangensis CAU 1447 had beneficial effects on wound healing and can be utilized as postbiotic therapeutic agents.

IInvestigation of possible oxidative damage caused by formaldehyde exposure in the rat's heart and aorta tissue / Investigación de posible daño oxidativo causado por la exposición al formaldehído en el corazón de la rata y tejido de la aorta

SUMMARY: Formaldehyde (FA) is a toxic substance used frequently in the field of medicine as well as in many industrial areas. Especially people working in the field of anatomy, histology, and pathology are in high risk group because of the use of the FA. Studies showing the effects of FA on the cardiovascular system are few in number. The purpose of the present study was to investigate the effects of FA exposure, which we believe can cause oxidative stress, on the heart and aorta with various biochemical analyses. A total of 24 Wistar Albino rats were used in our study. We divided the rats into 3 groups as the Control Group (CG), the group exposed to low-dose FA (avg. 1 ppm) (DDG) Group, and the group exposed to high-dose FA (avg. 10 ppm) (YDG). At the end of the subchronic FA exposure, the blood samples, heart and aorta tissues of the rats were taken and subjected to biochemical analyses. As a result of the analyses, statistically significant differences were detected between CG (2.96?0.85 ng/mg), and HDG (2.08?0.77 ng/mg) in aortic tissues in TXNIP analysis (p<0.05). In heart tissues, significant differences were detected between CG (0.73?0.27 ng/mg) and LDG (1.13?0.22 ng/mg) (p<0.05). Statistically significant differences were also detected between CG (1.98?0.31 mM/ml) and YDG (2.43?0.31 mM/ml) in serum MDA analyses (p<0.05). It was shown that subchronic application of FA to LDG rats through inhalation had no effects on apoptosis markers in heart tissues. More studies are required to show FA toxicity and the mechanism of action of pathology on the cardiovascular system. We believe that our study will contribute to clarifying the roles of mild and subchronic exposure of FA in heart and aortic tissues in terms of oxidative stress risk.

RESUMEN: El formaldehído es una sustancia tóxica que se utiliza con frecuencia en el campo de la medicina, así como en muchas áreas industriales. Especialmente las personas que trabajan en el area de la anatomía, y patología se encuentran en el grupo de alto riesgo debido al uso de esta sustancia. Pocos son los estudios que muestran los efectos del formaldehído en el sistema cardiovascular. El propósito del presente estudio fue investigar a través de análisis bioquímicos, los efectos de la exposición a formaldehído, que podría causar estrés oxidativo, en el corazón y la aorta. Se utilizaron un total de 24 ratas Albinas Wistar. Dividimos a las ratas en 3 grupos: grupo control (GC), grupo expuesto a dosis bajas de AG (promedio 1 ppm) (DDG) y grupo expuesto a dosis altas de AG (promedio 10 ppm) (YDG). Al término de la exposición a FA subcrónica, se tomaron muestras de sangre, tejido cardíaco y aorta de las ratas y se sometieron a análisis bioquímicos. Como resultado de los análisis, se detec- taron diferencias estadísticamente significativas entre GC (2,96 ? 0,85 ng / mg) y HDG (2,08 ? 0,77 ng / mg) en los tejidos aórticos en el análisis TXNIP (p <0,05). En los tejidos cardíacos se detectaron diferencias significativas entre GC (0,73 ? 0,27 ng / mg) y LDG (1,13 ? 0,22 ng / mg) (p <0,05). También se detectaron diferencias estadísticamente significativas entre CG (1,98 ? 0,31 mM / ml) y YDG (2,43 ? 0,31 mM / ml) en los análisis de MDA en suero (p <0,05). Se demostró que la aplicación subcrónica de formaldehído a ratas LDG a través de la inhalación no tuvo efectos sobre los marcadores de apoptosis en los tejidos del corazón. Se requieren más estudios para demostrar la toxicidad de los AG y el mecanismo de acción de la patología en el sistema cardiovascular. Creemos que nuestro estudio contribuirá a aclarar las funciones de la exposición leve y subcrónica de formaldehído en los tejidos cardíacos y aórticos en términos de riesgo al estrés oxidativo.

"Green" Prussian Blue Analogues as Peroxidase Mimetics for Amperometric Sensing and Biosensing.

Prussian blue analogs (PBAs) are well-known artificial enzymes with peroxidase (PO)-like activity. PBAs have a high potential for applications in scientific investigations, industry, ecology and medicine. Being stable and both catalytically and electrochemically active, PBAs are promising in the construction of biosensors and biofuel cells. The "green" synthesis of PO-like PBAs using oxido-reductase flavocytochrome b2 is described in this study. When immobilized on graphite electrodes (GEs), the obtained green-synthesized PBAs or hexacyanoferrates (gHCFs) of transition and noble metals produced amperometric signals in response to H2O2. HCFs of copper, iron, palladium and other metals were synthesized and characterized by structure, size, catalytic properties and electro-mediator activities. The gCuHCF, as the most effective PO mimetic with a flower-like micro/nano superstructure, was used as an H2O2-sensitive platform for the development of a glucose oxidase (GO)-based biosensor. The GO/gCuHCF/GE biosensor exhibited high sensitivity (710 A M-1m-2), a broad linear range and good selectivity when tested on real samples of fruit juices. We propose that the gCuHCF and other gHCFs synthesized via enzymes may be used as artificial POs in amperometric oxidase-based (bio)sensors.

Core-Shell Nanozymes "Artificial Peroxidase": Stability with Superior Catalytic Properties.

We report on the nanoparticles composed of the catalytically synthesized Prussian Blue (PB) core stabilized with the nickel hexacyanoferrate (NiHCF) shell. Catalyzing hydrogen peroxide reduction, the resulting nanozymes (ø = 66 nm) display catalytic rate constants, which for pyrogallol or ferrocyanide are, respectively, 25 and 35 times higher than those for peroxidase enzyme. After more than half a year of storage at a room temperature, the core-shell PB-NiHCF nanozymes retain both their size and physicochemical properties; such stability is unreachable for the enzymes. Being immobilized, core-shell PB-NiHCF nanozymes (ø = 45 nm) result in a hydrogen peroxide sensor with a sensitivity similar to that of the sensor based on sole PB nanoparticles. However, whereas the latter response in hard inactivating conditions (25 min in 1 mM H2O2) drops down to 7.5%, the PB-NiHCF nanozymes-based sensor retains >75% of initial sensitivity. Application of the core-shell PB-NiHCF nanozymes "artificial peroxidase" would obviously open new horizons in elaboration of anti-inflammatory drugs and (bio)sensors.

Structural differences of neutrophil extracellular traps induced by biochemical and microbiologic stimuli under healthy and autoimmune milieus.

Neutrophil extracellular traps (NETs) are networks of decondensed chromatin loaded with antimicrobial peptides and enzymes produced against microorganisms or biochemical stimuli. Since their discovery, numerous studies made separately have revealed multiple triggers that induce similar NET morphologies allowing to classify them as lytic or non-lytic. However, the variability in NET composition depending on the inducer agent and the local milieu under similar conditions has been scarcely studied. In this work, a comparative study was conducted to evaluate structural and enzymatic divergences in NET composition induced by biochemical (phorbol myristate acetate [PMA] and hypochlorous acid [HOCl]) and microbiologic (Candida albicans, Staphylococcus aureus, and Pseudomonas aeruginosa) stimuli, along with the presence of plasma from healthy donors or patients with systemic lupus erythematosus (SLE). The results showed a differential composition of DNA and the antimicrobial peptide cathelicidin (LL37) and a variable enzymatic activity (neutrophil elastase, cathepsin G, myeloperoxidase) induced by the different stimuli despite showing morphologically similar NETs. Additionally, SLE plasma´s presence increased DNA and LL37 release during NET induction independently of the trigger stimulus but with no enzymatic activity differences. This work provides new evidence about NET composition variability depending on the inducer stimulus and the local milieu.

Effects of a combined water and sanitation intervention on biomarkers of child environmental enteric dysfunction and associations with height-for-age z-score: A matched cohort study in rural Odisha, India.

Poor water, sanitation and hygiene (WaSH) conditions are hypothesized to contribute to environmental enteric dysfunction (EED), a subclinical condition that may be associated with chronic undernutrition and impaired linear growth. We evaluated the effect of a combined water and sanitation intervention on biomarkers of EED, and then assessed associations of biomarkers of EED with height-for-age z-scores (HAZ), in children under five. We conducted a sub-study within a matched cohort study of a household-level water and sanitation infrastructure intervention in rural Odisha, India, in which we had observed an effect of the intervention on HAZ. We collected stool samples (N = 471) and anthropometry data (N = 209) for children under age 5. We analyzed stool samples for three biomarkers of EED: myeloperoxidase (MPO), neopterin (NEO), and α1-anti-trypsin (AAT). We used linear mixed models to estimate associations between the intervention and each biomarker of EED and between each biomarker and HAZ. The intervention was inversely associated with AAT (-0.25 log µg/ml, p = 0.025), suggesting a protective effect on EED, but was not associated with MPO or NEO. We observed an inverse association between MPO and HAZ (-0.031 per 1000 ng/ml MPO, p = 0.0090) but no association between either NEO or AAT and HAZ. Our results contribute evidence that a transformative WaSH infrastructure intervention may reduce intestinal permeability, but not intestinal inflammation and immune activation, in young children. Our study also adds to observational evidence of associations between intestinal inflammation and nutritional status, as measured by HAZ, in young children. Trial Registration: ClinicalTrials.gov (NCT02441699).