Voltage-dependent cationic channels formed by a cytolytic toxin produced by Gardnerella vaginalis

AbstractA cytolytic toxin produced by G. vaginalis was incorporated in artificial membranes and giant liposomes. The toxin formed ionic channels when incorporated in lipid bilayers. The electrical properties of such channels were studied. Current records revealed a unitary conductance of 126 pS (in symmetrical 150 mM KCl). The open state probability of the cytolysin formed channels was a function of the applied membrane potential. The permeability ratio of cations to anions was estimated to be 6.5

Nanomolar CFTR Inhibition by Pore-Occluding Divalent Polyethylene Glycol-Malonic Acid Hydrazides

SummaryInhibitors of the cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel have potential application as antisecretory therapy in cholera. We synthesized mono- and divalent CFTR inhibitors consisting of a malonic acid hydrazide (MalH) coupled via a disulfonic stilbene linker to polyethylene glycols (PEGs; 0.2–100 kDa). IC50 values for CFTR inhibition were 10–15 μM for the monovalent MalH-PEGs, but substantially lower for divalent MalH-PEG-MalH compounds, decreasing from 1.5 to 0.3 μM with increasing PEG size and showing positive cooperativity. Whole-cell patch-clamp showed voltage-dependent CFTR block with inward rectification. Outside-out patch-clamp showed shortened single-channel openings, indicating CFTR pore block from the extracellular side. Luminally added MalH-PEG-MalH blocked by >90% cholera toxin-induced fluid secretion in mouse intestinal loops (IC50 ∼10 pmol/loop), and greatly reduced mortality in a suckling mouse cholera model. These conjugates may provide safe, inexpensive antisecretory therapy

Корреляция генотипа с фенотипом у больных муковисцидозом

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IL-4 Is a Potent Modulator of Ion Transport in the Human Bronchial Epithelium In Vitro

AbstractRecent data show that proinflammatory stimuli may modify significantly ion transport in the airway epithelium and therefore the properties of the airway surface fluid. We have studied the effect of IL-4, a cytokine involved in the pathogenesis of asthma, on transepithelial ion transport in the human bronchial epithelium in vitro. Incubation of polarized bronchial epithelial cells with IL-4 for 6–48 h causes a marked inhibition of the amiloride-sensitive Na+ channel as measured in short circuit current experiments. On the other hand, IL-4 evokes a 2-fold increase in the current activated by a cAMP analog, which reflects the activity of the cystic fibrosis transmembrane conductance regulator (CFTR). Similarly, IL-4 enhances the response to apical UTP, an agonist that activates Ca2+-dependent Cl− channels. These effects are mimicked by IL-13 and blocked by an antagonist of IL-4Rα. RT-PCR experiments show that IL-4 elicits a 7-fold decrease in the level of the γ amiloride-sensitive Na+ channel mRNA, one of the subunits of the amiloride-sensitive Na+ channel, and an increase in CFTR mRNA. Our data suggest that IL-4 may favor the hydration of the airway surface by decreasing Na+ absorption and increasing Cl− secretion. This could be required to fluidify the mucus, which is hypersecreted during inflammatory conditions. On the other hand, the modifications of ion transport could also affect the ion composition of airway surface fluid

In vitro recapitulation of the site-specific editing (to wild-type) of mutant IDS mRNA transcripts, and the characterization of IDS protein translated from the edited mRNAs

The transfer of genomic information into the primary RNA sequence can be altered by RNA editing. We have previously shown that genomic variants can be RNA-edited to wild-type. The presence of distinct “edited” iduronate 2-sulfatase (IDS) mRNA transcripts ex vivo evidenced the correction of a nonsense and frameshift variant, respectively, in three unrelated Hunter syndrome patients. This phenomenon was confirmed in various patient samples by a variety of techniques, and was quantified by single-nucleotide primer extension. Western blotting also confirmed the presence of IDS protein similar in size to the wild-type. Since preliminary experimental evidence suggested that the “corrected” IDS proteins produced by the patients were similar in molecular weight and net charge to their wild-type counterparts, an in vitro system employing different cell types was established to recapitulate the site-specific editing of IDS RNA (uridine to cytidine conversion and uridine deletion), and to confirm the findings previously observed ex vivo in the three patients. In addition, confocal microscopy and flow cytometry analyses demonstrated the expression and lysosomal localization in HEK293 cells of GFP-labeled proteins translated from edited IDS mRNAs. Confocal high-content analysis of the two patients’ cells expressing wild-type or mutated IDS confirmed lysosomal localization and showed no accumulation in the Golgi or early endosomes

Prevalence of Diabetes Mellitus and Its Associated Unfavorable Outcomes in Patients With Acute Respiratory Syndromes Due to Coronaviruses Infection: A Systematic Review and Meta-Analysis

Introduction: Only 3 types of coronavirus cause aggressive respiratory disease in humans (MERS-Cov, SARS-Cov-1, and SARS-Cov-2). It has been reported higher infection rates and severe manifestations (ICU admission, need for mechanical ventilation, and death) in patients with comorbidities such as diabetes mellitus (DM). For this reason, this study aimed to determine the prevalence of diabetes comorbidity and its associated unfavorable health outcomes in patients with acute respiratory syndromes for coronavirus disease according to virus types. Methods: Systematic review of literature in Pubmed/Medline, Scopus, Web of Science, Cochrane, and Scielo until April of 2020. We included cohort and cross-sectional studies with no restriction by language or geographical zone. The selection and extraction were undertaken by 2 reviewers, independently. The study quality was evaluated with Loney’s instrument and data were synthesized by random effects model meta-analysis. The heterogeneity was quantified using an I2 statistic. Funnel plot, Egger, and Begg tests were used to evaluate publication biases, and subgroups and sensitivity analyses were performed. Finally, we used the GRADE approach to assess the evidence certainty (PROSPERO: CRD42020178049). Results: We conducted the pooled analysis of 28 studies (n = 5960). The prevalence analysis according to virus type were 451.9 diabetes cases per 1000 infected patients (95% CI: 356.74-548.78; I2 = 89.71%) in MERS-Cov; 90.38 per 1000 (95% CI: 67.17-118.38) in SARS-Cov-1; and 100.42 per 1000 (95% CI: 77.85, 125.26 I2 = 67.94%) in SARS-Cov-2. The mortality rate were 36%, 6%, 10% and for MERS-Cov, SARS-Cov-1, and SARS-Cov-2, respectively. Due to the high risk of bias (75% of studies had very low quality), high heterogeneity (I2 higher than 60%), and publication bias (for MERS-Cov studies), we down rate the certainty to very low. Conclusion: The prevalence of DM in patients with acute respiratory syndrome due to coronaviruses is high, predominantly with MERS-Cov infection. The unfavorable health outcomes are frequent in this subset of patients. Well-powered and population-based studies are needed, including detailed DM clinical profile (such as glycemic control, DM complications, and treatment regimens), comorbidities, and SARS-Cov-2 evolution to reevaluate the worldwide prevalence of this comorbidity and to typify clinical phenotypes with differential risk within the subpopulation of DM patients.Revisión por pare

Associação entre estilos parentais e o papel de adolescentes peruanos no bullying, 2019

Introduction: Parenting styles determine child behavior; however, there is little information on their impact on bullying. Objective: To determine the association between different parenting styles and the role assumed in bullying, as well as to identify adolescents’ profiles according to their involvement in bullying. Materials and Methods: A cross-sectional analytical study was conducted in Lima, Peru, in 2019. The Steinberg’s Parenting Styles Scale and the European Bullying Intervention Project Questionnaire (EBIP-Q) were administered to 563 students from public schools. Scores were obtained by confirmatory factor analysis. Spearman’s correlation coefficient, Pearson’s Chi-square test, and multinomial logistic regression analysis were used. Results: There is an association between parenting styles and adolescents’ role in bullying. The multivariate analysis reported that being male was associated with the role of the bully (OR: 2.73; 95% CI 1.59–4.68), while access to social media (OR: 2.23; CI 95% 1.11–4.49), being male (OR: 1.75; CI=1.06–2.88), and parenting styles (neglectful [OR: 2.72; 95% CI 1.32–5.59] and mixed [OR: 0.38; 95% CI 0.16–0.91] compared to authoritarian parenting style) were predictors of the role of the victimized bully. Discussion: The association found in the study confirms previous findings; however, it opens the debate on the influence of neglectful parenting style on bullying dynamics. Conclusions: Both neglectful and authoritarian parenting styles (lower proportion) have a positive and significant effect on the role of victimized bully. How to cite this article: Zegarra Chapoñan Roberto, Zeladita Huaman Jhon Alex, Cuba Sancho Juana Matilde, Castillo Parra Henry, Moran Paredes Gladys Ivonne, Cárdenas Niño Lucila. Asociación entre los estilos de crianza y el rol de los adolescentes peruanos en el acoso escolar, 2019. Revista Cuidarte. 2023;14(1):e2679.  http://dx.doi.org/10.15649/cuidarte.2679Highlights: Existe consenso científico de que las diferentes tipologías de los estilos de crianza de los padres se asocian con el rol que asumen sus hijos en el acoso escolar. Los adolescentes educados en un estilo de crianza negligente en comparación con el estilo de crianza autoritario tienen el doble de probabilidad de ser agresor victimizado. Los adolescentes hombres tienen mayor probabilidad en comparación con las mujeres en asumir el rol de agresor, así como también el rol de agresor victimizado. La incorporación del enfermero a la comunidad educativa, aprobado por la legislación peruana en el año 2021, permitirá prevenir la violencia escolar y promover la cultura de paz. Introducción. Los estilos de crianza determinan la conducta infantil; sin embargo, existe escasa información sobre su repercusión en el acoso escolar. Objetivo: Determinar la fuerza de asociación entre las diferentes tipologías de los estilos de crianza y el rol asumido en el acoso escolar, así como identificar perfiles de los adolescentes según su involucramiento en el acoso escolar. Materiales y métodos. Estudio transversal tipo analítico, realizado en Lima-Perú, en el año 2019. Se aplicó la escala de estilos de crianza de Steinberg y la escala EBIP-Q a 563 escolares de escuelas públicas. Los puntajes fueron obtenidos mediante un análisis factorial confirmatorio. Se empleó el coeficiente de correlación de Spearman, Chi Cuadrado de Pearson y análisis de regresión logística multinomial. Resultados.  Existe asociación entre los estilos de crianza y el rol del adolescente en el acoso escolar. El análisis multivariado reportó que ser hombres se asocia con el rol de agresor (OR = 2,73); mientras que acceder a una red social (OR = 2,23), ser hombre (OR = 1,75), los estilos de crianza (negligente [OR = 2,72] y mixto [OR = 0,38] en comparación con autoritario) fueron predictores de asumir el rol de agresor victimizado en el acoso escolar. Discusión. La asociación encontrada en el estudio confirma hallazgos previos; sin embargo, se abre debate sobre la influencia del estilo de crianza negligente en la dinámica del acoso escolar. Conclusión. Tanto el estilo de crianza negligente y autoritario (menor proporción) tienen un efecto positivo y significativo en el rol de agresor victimizado. Como citar este artículo: Zegarra Chapoñan Roberto, Zeladita Huaman Jhon Alex, Cuba Sancho Juana Matilde, Castillo Parra Henry, Moran Paredes Gladys Ivonne, Cárdenas Niño Lucila. Asociación entre los estilos de crianza y el rol de los adolescentes peruanos en el acoso escolar, 2019. Revista Cuidarte. 2023;14(1):e2679.  http://dx.doi.org/10.15649/cuidarte.2679Introdução: Os estilos parentais determinam o comportamento das crianças; no entanto, há pouca informação sobre o seu impacto no bullying. Objetivo: Determinar a força da associação entre os diferentes estilos parentais e o papel assumido no bullying; bem como identificar perfis de adolescentes de acordo com seu envolvimento no bullying. Materiais e métodos: Estudo analítico transversal realizado em Lima-Peru em 2019. A escala de estilos parentais de Steinberg e a escala EBIP-Q foram aplicadas a 563 alunos de escolas públicas. Os escores foram obtidos por meio de uma análise fatorial confirmatória. Foram utilizados o coeficiente de correlação de Spearman, o Qui-Quadrado de Pearson e a análise de regressão logística multinomial. Resultados: Existe associação entre os estilos parentais e o papel do adolescente no bullying. A análise multivariada relatou que ser do sexo masculino está associado ao papel de agressor (OR: 2,73; IC 95% 1,59-4,68); ao acessar uma rede social (OR: 2,23; IC 95% 1,11-4,49), ser do sexo masculino (OR: 1,75; IC=1,06-2,88), estilos parentais (negligente [OR: 2,72; IC 95% 1,32-5,59] e misto [OR: 0,38; IC 95% 0,16-0,91] comparado ao autoritário) foram preditores de assumir o papel de agressor vitimizado no bullying. Discussão: A associação encontrada no estudo confirma achados anteriores; no entanto, abre-se um debate sobre a influência do estilo parental negligente na dinâmica do bullying. Conclusão: Tanto o estilo parental negligente quanto o autoritário (menor proporção) têm efeito positivo e significativo no papel do agressor vitimizado. Como citar este artigo: Zegarra Chapoñan Roberto, Zeladita Huaman Jhon Alex, Cuba Sancho Juana Matilde, Castillo Parra Henry, Moran Paredes Gladys Ivonne, Cárdenas Niño Lucila. Asociación entre los estilos de crianza y el rol de los adolescentes peruanos en el acoso escolar, 2019. Revista Cuidarte. 2023;14(1):e2679.  http://dx.doi.org/10.15649/cuidarte.267

Anion-transport mechanism of a triazole-bearing derivative of prodigiosine: a candidate for cystic fibrosis therapy

Cystic fibrosis (CF) is a genetic lethal disease, originated from the defective function of the CFTR protein, a chloride and bicarbonate permeable transmembrane channel. CF mutations affect CFTR protein through a variety of molecular mechanisms which result in different functional defects. Current therapeutic approaches are targeted to specific groups of patients that share a common functional defect. We seek to develop an innovative therapeutic approach for the treatment of CF using anionophores, small molecules that facilitate the transmembrane transport of anions. We have characterized the anion transport mechanism of a synthetic molecule based on the structure of prodigiosine, a red pigment produced by bacteria. Anionophore-driven chloride efflux from large unilamellar vesicles is consistent with activity of an uniporter carrier that facilitates the transport of anions through lipid membranes down the electrochemical gradient. There are no evidences of transport coupling with protons. The selectivity sequence of the prodigiosin inspired EH160 ionophore is formate > acetate > nitrate > chloride > bicarbonate. Sulfate, phosphate, aspartate, isothionate, and gluconate are not significantly transported by these anionophores. Protonation at acidic pH is important for the transport capacity of the anionophore. This prodigiosin derived ionophore induces anion transport in living cells. Its low toxicity and capacity to transport chloride and bicarbonate, when applied at low concentration, constitute a promising starting point for the development of drug candidates for CF therapy.European Union’s Horizon 2020 research and innovation programme under grant agreement No 667079 and Consejería de Educación de la Junta de Castilla y León (Project BU092U16)

TITLE PAGE α-AMINOAZAHETEROCYCLIC-METHYLGLYOXAL ADDUCTS DO NOT INHIBIT CFTR CHLORIDE CHANNEL ACTIVITY

ABSTRACT Inhibitors of the cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel have potential applications in the therapy of secretory diarrheas and polycystic kidney disease. Recently, several highly polar α-aminoazaheterocyclic-methylglyoxal adducts were reported to reversibly inhibit CFTR chloride channel activity with IC50 values in the low picomolar range (Routaboul et al. J. Pharmacol. Exp. Ther. 322:1023-1035, more than 10,000-fold better than that of thiazolidionone and glycine hydrazide CFTR inhibitors identified previously by highthroughout screening. Here, we resynthesized and evaluated the α-aminoazaheterocyclicmethylglyoxal adducts of Routaboul et al. reported to have high CFTR inhibition potency (compounds 5, 7 and 8). We verified that the reported synthesis procedures produced the target compounds in high yield. However, we found that these compounds did not inhibit CFTR chloride channel function in multiple cell lines at up to 100 µM concentration, using three independent assays of CFTR function including short-circuit current analysis, whole-cell patch-clamp and YFPfluorescence quenching. As positive controls, near 100% CFTR inhibition was found by thiazolidionone and glycine hydrazide CFTR inhibitors. Our data provide direct evidence against CFTR inhibition by α-aminoazaheterocyclic-methylglyoxal adducts