3,726 research outputs found
Climate change and its influence in nephron mass
PURPOSE OF REVIEW
The consequences of climate change, including heat and extreme weather events impact kidney function in adults and children. The impacts of climate change on kidney development during gestation and thereby on kidney function later in life have been poorly described. Clinical evidence is summarized to highlight possible associations between climate change and nephron mass.
RECENT FINDINGS
Pregnant women are vulnerable to the effects of climate change, being less able to thermoregulate, more sensitive to the effects of dehydration, and more susceptible to infections. Exposure to heat, wildfire smoke, drought, floods and climate-related infections are associated with low birth weight, preterm birth and preeclampsia. These factors are associated with reduced nephron numbers, kidney dysfunction and higher blood pressures in offspring in later life. Exposure to air pollution is associated with higher blood pressures in children and has variable effects on estimated glomerular filtration rate.
SUMMARY
Climate change has important impacts on pregnant women and their unborn children. Being born too small or too soon is associated with life-time risk of kidney disease. Climate change may therefore have a dual effect of impacting fetal kidney development and contributing to cumulative postnatal kidney injury. The impact on population kidney health of future generations may be significant
Bases estructurales del mecanismo de reconocimiento y fosfotransferencia en los sistemas de señalización de dos componentes
Póster original presentado XXVII Congreso de la SEBBM, Sociedad Española de Bioquímica y Biología
Molecular, celebrado en Lleida, 12-15 de septiembre, 2004.Los sistemas de dos componentes son el mecanismo principal de transducción de señal en microorganismos. Un sistema paradigmático se compone de dos proteínas: una histidina quinasa (HK) y un regulador de la respuesta (RR). El mecanismo de transducción de señal implica al menos tres reacciones (ver esquema): 1) Autofosforilación: la llegada de un estímulo al dominio extracelular sensor de la HK, induce la fosforilación en un residuo de His conservado en el dominio de dimerización (DHp) por parte del dominio de unión de ATP (CA). 2) Fosfotransferencia: este grupo fosforilo es transferido desde la His a un residuo de Asp del dominio regulador del correspondiente RR. 3) Defosforilación: el RR pierde el grupo fosforilo espontáneamente o mediado por la HK. El estado de fosforilación del dominio regulador en RR regula la actividad de su dominio efector, que es habitualmente un factor de transcripción.Financiado por la ayuda BIO2002-03709 del Ministerio de Ciencia y Tecnología. P. casino es becaria FPI del Ministerio de ciencia y TecnologíaPeer reviewe
Biological treatment of solid wastes from the tobacco industry for enzyme production
Aiming at the production of enzymes using solid wastes from the tobacco industry, the solid fermentation
kinetics of Aspergillus niger and Aspergillus terreus using waste of dark tobacco and Virginia tobacco as
substrate were characterized.
The efficiency of the fermentation process was evaluated by determining the enzymatic activity of the three
enzymes that constitute the cellulose enzymatic system (CMCase, PFase and Xylanase).
The results obtained led to the establishment of the best initial conditions of fermentation and the selection
of the most efficient microorganism for enzyme production. The best results were obtained with
Aspergillus terreus for both tobacco residues. In the case of black tobacco, the best incubation temperature
was 31 ºC for the enzymes CMCase and Xylanase and 36 ºC for the PFase and initial pH 5.5 for the three
enzymes. For the Virginia tobacco, the best incubation temperature and initial pH are the same for the three
enzymes, 36 ºC and 5.5 respectively.
The biological activity of the fermented tobacco residues was evaluated being the highest rate of inhibition
of microbial growth – 72% - obtained with the residue of Virginia tobacco treated with Aspergillus niger
the role of relationship characteristics
Funding Information: Funding: This work received Portuguese national funding from FCT \u2013 Funda\u00E7\u00E3o para a Ci\u00EAncia e a Tecnologia, I.P, through a research project grant involving all authors (PTDC/PSIGER/28530/2017) and through the Research Center for Psychological Science of the Faculty of Psychology, University of Lisbon (UIDB/04527/2020; UIDP/04527/2020). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Publisher Copyright: Copyright: © 2024 Godinho et al.Background While the existence of a complex variety of casual sexual relationships (CSRs) has been acknowledged, studies rarely describe the prevalence of condom use across these relationships or how their hybrid nature, specifically relationship characteristics, affect condom use. This study aims to describe condom use within committed relationships and various types of casual sexual relationships (CSRs), examining the influence of relationship characteristics on condom use among culturally validated relationship types (committed, friends with benefits, hookups, booty call). Methods Emerging adults (N = 728, 18–29 years, M = 22.56; SD = 3.01) completed a survey with four blocks: sociodemographics; brief sexual history; relationships over the previous year; and current relationship, assessing relationship type, ten relationship characteristics (e.g., commitment, emotional and sexual exclusivity, partner acquaintance, sexual involvement) and condom use (vaginal, oral, and anal), operationalized by three measures (use at last encounter, likert-type scale and percentage of use). Results The results showed patterns in condom use by relationship type and illuminated how relationship characteristics—grouped into three factors: commitment, intimacy, and sexuality—mediate condom use. Condom use was more frequent in vaginal than anal and oral sex, and less frequent in committed relationships. No significant differences were found in condom use in vaginal sex between committed relationships and hookups, with condom in these relationships being significantly lower than in booty call. Intimacy mediated between all contrasts tested and condom use in vaginal sex, while sexuality mediated between committed vs. CSRs and condom use in anal and oral sex. Conclusions Findings point to the need of considering the diversity of CSRs for understanding condom use and highlight the role of intimacy as a relevant mechanism associated with condom use in vaginal sex and of sexuality in oral and anal sex, which should be taken into consideration in the tailoring of health promoting efforts.publishersversionpublishe
Estrogens promote misfolded proinsulin degradation to protect insulin production and delay diabetes
Summary: Conjugated estrogens (CE) delay the onset of type 2 diabetes (T2D) in postmenopausal women, but the mechanism is unclear. In T2D, the endoplasmic reticulum (ER) fails to promote proinsulin folding and, in failing to do so, promotes ER stress and β cell dysfunction. We show that CE prevent insulin-deficient diabetes in male and in female Akita mice using a model of misfolded proinsulin. CE stabilize the ER-associated protein degradation (ERAD) system and promote misfolded proinsulin proteasomal degradation. This involves activation of nuclear and membrane estrogen receptor-α (ERα), promoting transcriptional repression and proteasomal degradation of the ubiquitin-conjugating enzyme and ERAD degrader, UBC6e. The selective ERα modulator bazedoxifene mimics CE protection of β cells in females but not in males. : Estrogens prevent diabetes in women, but the mechanism is poorly understood. Xu et al. report that estrogens activate the endoplasmic-reticulum-associated protein degradation pathway, which promotes misfolded proinsulin degradation, suppresses endoplasmic reticulum stress, and protects insulin secretion in mice and in human pancreatic β cells. Keywords: estrogens, beta cell, islet, endoplasmic reticulum stress, proinsulin misfolding, diabetes, bazedoxifene, sex dimorphism, ERAD, SER
Patrones de producción y consumo responsable: La carrera por el logro de los Objetivos de Desarrollo Sostenible (ODS) en mercados emergentes
Since the end of the 20th century, the role of private multinational enterprises (MNEs) has been recognized as critical in implementing increased sustainable production and consumption atterns. Particularly after the creation of the Sustainable Development Goals (SDGs) and the Agenda 2030, this role has increased. In this sense, this paper aims to analyze the measures and actions taken by companies in their contribution to the achievement of the SDG 12. Through the identification of more than 52 metrics in sustainability reports of 854 firms, findings suggest that direct greenhouse gas emissions and indirect greenhouse gas emissions are the most often reported corporate metrics to measure their impact on specific SDGs. This reveals the importance of sustainability actions in emerging market firms as a mechanism to gain legitimacy when operating in foreign markets and as an opportunity to create more sustainable production models.Desde finales del siglo XX, se ha reconocido que el papel de las empresas multinacionales (EMN) privadas es fundamental en el proceso de implementación de patrones de producción y consumo más sostenibles. Especialmente, tras la creación de los Objetivos de Desarrollo Sostenible (ODS) y la Agenda 2030, este papel ha aumentado. En este sentido, este trabajo tiene como objetivo analizar las medidas y acciones tomadas por las empresas en su contribución al logro del ODS 12. Mediante la identificación de más de 52 métricas en los informes de sostenibilidad de 854 empresas, los hallazgos sugieren que las emisiones directas de gases de efecto invernadero y las emisiones indirectas de gases de efecto invernadero son las métricas corporativas con más información para medir su impacto en ODS específicos. Esto revela la importancia de las acciones de sostenibilidad en las empresas de mercados emergentes como mecanismo para ganar legitimidad al operar en mercados externos y como oportunidad para la creación de modelos de producción más sostenibles
Improved Triamcinolone acetonide-eluting contact lenses based on cyclodextrins and high hydrostatic pressure assisted complexation
© 2024 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Contact lenses (CLs) constitute an advantageous platform for the topical release of corticosteroids due to their prolonged contact with the eye. However, the lipophilic nature of corticosteroids hampers CLs' ability to release therapeutic amounts. Two approaches to improve loading and release of triamcinolone acetonide (TA) from poly(2-hydroxyethyl methacrylate)-based hydrogels were investigated: adding 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) to the monomers solution before polymerization (HEMA/i-CD) and an hydrogels' post-treatment with HP-β-CD (HEMA/p-CD). The effect of HP-β-CD and sterilization by high hydrostatic pressure (HHP) on the hydrogel properties (water content, oxygen and ion permeability, roughness, transmittance, and stiffness) was evaluated. The HEMA/i-CD hydrogels had stronger affinity for TA, sustaining its release for one day. HHP sterilization promoted the formation of cyclodextrin-TA complexes within the hydrogels, improving their drug-loading capacity »60 %. Cytotoxicity and irritability tests confirmed the safety of the therapeutic CLs. TA released from the hydrogels permeated through ocular tissues ex vivo and showed anti-inflammatory activity. Finally, a previously validated mathematical model was used to estimate the ability of the TA-loaded CLs to deliver therapeutic drug concentrations to the posterior part of the eye. Overall, HP-β-CD-containing CLs are promising candidates for the topical ocular application of TA as an alternative delivery system to intraocular injections.Work supported by Fundação para a Ciência e a Tecnologia (FCT) through [doi: 10.54499/UIDB/00100/2020] and [doi: 10.54499/UIDP/00100/2020] (CQE), [doi: 10.54499/UIDB/04585/2020] (CiiEM) and [doi:10.54499/PTDC/CTM-CTM/2353/2021] (SOL project), University of Aveiro and FCT/MCT through [UIDB/50006/2020 and UIDP/50006/2020] (LAQV-REQUIMTE) co-funded by the FEDER within PT2020 Partnership Agreement, and MCIN/AEI/10.13039/501100011033 Spain [PID 2020-113881RB-I00], Xunta de Galicia [ED431C 2020/17], and FEDER. The authors acknowledge SICASAL - Indústria e Comércio de Carnes, S.A. for the kind supply of porcine fresh eyes and to Dr. Nuno Taveira from the University of Lisbon for providing THP-1 human monocytes cell line. ASHLAND kindly provided Cavasol® W7 HP PHARMA (HP-β-CD). The Graphical Abstract was created by using pictures from Servier Medical Art., by Servier, licensed under a Creative Commons Attribution 3.0 Unported License (https://creativecommons.org/licenses/by/3.0/).info:eu-repo/semantics/publishedVersio
The use of a silicone-based biomembrane for microaerobic H2S removal from biogas
A lab-scale bio-membrane unit was developed to improve H2S removal from biogas through microaeration. Biomembrane separated biogas from air and consisted of a silicone tube covered by microaerobic biofilm. This setup allowed efficient H2S removal while minimizing biogas contamination with oxygen and nitrogen. The transport and removal of H2S, N-2, O-2, CH4 and CO2 through bare membrane, wet membrane and biomembrane was investigated. Membrane allowed the transfer of gases through it as long as there was enough driving force to induce it. H2S concentration in biogas decreased much faster with the biomembrane. The permeation of gases through the membranes decreased in order: H2S > CO2 > CH4 > O-2 > N-2. H2S removal efficiency of more than 99% was observed during the continuous experiment. Light yellow deposits on the membrane indicated the possible elemental sulfur formation due to biological oxidation of H2S. Thiobacillus thioparus was detected by FISH and PCR-DGGE
Mechanism of the negative inotropic effect of naringin in mouse heart [Mecanismo del efecto inotrópico negativo de la naringina en el corazón de ratón]
Abstract Resumen Context: Naringin (NRG) is the major flavonoid (flavanone glycoside) in grapefruit juice. Its biological activity has been only partially characterized and little is known about the mechanism of the negative inotropic action of this flavonoid. Aims: To evaluate the effects of NRG on the surface electrogram (ECG) and the force of contraction (FC) of mice hearts as well as on the sodium (INa), calcium (ICaL) and Na + -Ca 2+ exchange (INaCaX) currents of enzymatically isolated mouse ventricular cardiomyocytes. Methods: ECG and FC were recorded on mouse hearts perfused in a Langendorff column. Ventricular cardiomyocytes were enzimatically dissociated and ionic currents recorded with the patch-clamp technique. Results: NRG increased RR interval and shortened corrected QT only at high concentrations (30-100 µM). However, at a fixed heart rate, it decreased FC with an IC50 of 0.4 µM. NRG reduced INa with an IC50 of 0.07 µM but with a maximal inhibition of 60 %. NRG also depressed ICaL with an IC50 of 0.013 µM and increased its fast inactivation time constant. The effects on ICaL were not voltage-dependent. INaCaX was not affected by NRG. Conclusions: Our results indicate that NRG exerts a negative inotropic effect in mice hearts that could be explained by a decrease in INa and ICaL. These actions should be taken into account when considering this molecule either as a dietetic supplement or as a template to develop therapeutic agents for human diseases. Contexto: La naringina (NRG) es el principal flavonoide (glicósido de flavanona) en el jugo de toronja. Su actividad biológica ha sido solo parcialmente caracterizada y poco se conoce acerca del mecanismo de la acción inotrópica negativa de este flavonoide. Objetivos: Evaluar los efectos de la NRG sobre el electrograma de superficie (ECG) y la fuerza de contracción (FC) de corazones de ratón, así como sobre las corrientes de sodio (INa), calcio (ICaL) y del intercambiador Na + -Ca 2+ (INaCaX) en cardiomiocitos ventriculares de ratón, aislados enzimáticamente. Métodos: El ECG y la FC se registraron en corazones de ratón perfundidos en una columna de Langendorff. Los cardiomiocitos ventriculares se disociaron enzimáticamente y las corrientes iónicas se registraron con la técnica de patch-clamp. Resultados: La NRG incrementó el intervalo RR intervalo y acortó el QT solo a altas concentraciones (30-100 µM). No obstante, a frecuencia cardíaca fija, disminuyó la FC con un IC50 de 0.4 µM. La NRG redujo INa con un IC50 de 0.07 µM pero con una máxima inhibición de 60 %. La NRG también redujo ICaL con un IC50 de 0.013 µM e incrementó su constante de inactivación rápida. Los efectos sobre ICaL no fueron dependientes del potencial. La INaCaX no fue afectada por la NRG. Conclusiones: Nuestros resultados indican que la NRG ejerce un efecto inotrópico negativo en corazones de ratón que puede ser explicado por una reducción en INa e ICaL. Esas acciones deben ser tomadas en cuenta al considerar a esta molécula como suplemento dietético o como plantilla para desarrollar nuevos agentes terapéuticos para tratar las enfermedades en humanos
Chemistry of a Nitrosyl Ligand ¿:¿-Bridging a Ditungsten Center: rearrangement and N–O Bond cleavage reactions
The novel nitrosyl-bridged complex [W2Cp2(μ-PtBu2)(μ-κ:η-NO)(CO)(NO)](BAr4) [Ar = 3,5-C6H3(CF3)2] was prepared in a multistep procedure starting from the hydride [W2Cp2(μ-H)(μ-PtBu2)(CO)4] and involving the new complexes [W2Cp2(μ-PtBu2)(CO)4](BF4), [W2Cp2(μ-PtBu2)(CO)2(NO)2](BAr4), and [W2(μ-κ:η5-C5H4)Cp(μ-PtBu2)(CO)(NO)2] as intermediates, which follow from reactions with HBF4·OEt2, NO, and Me3NO·2H2O, respectively. The nitrosyl-bridged cation easily added chloride upon reaction with [N(PPh3)2]Cl, with concomitant NO rearrangement into the terminal coordination mode, to give [W2ClCp2(μ-PtBu2)(CO)(NO)2], and underwent N–O and W–W bond cleavages upon the addition of CNtBu to give the mononuclear phosphinoimido complex [WCp(NPtBu2)(CNtBu)2](BAr4). Another N–O bond cleavage was induced upon photochemical decarbonylation at 243 K, which gave the oxo- and phosphinito-bridged nitrido complex [W2Cp2(N)(μ-O)(μ-OPtBu2)(NO)](BAr4), likely resulting from a N–O bond cleavage step following decarbonylation
- …