40 research outputs found

    The probiotic Lactobacillus rhamnosus mimics the dark-driven regulation of appetite markers and melatonin receptors' expression in zebrafish (Danio rerio) larvae: Understanding the role of the gut microbiome.

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    The use of probiotics has been recently considered a novel therapeutic strategy to prevent pathologies such as obesity; however, the specific mechanisms of action by which probiotics exert their beneficial effects on metabolic health remain unclear. The aim of the present study was to investigate the short-term effects of a probiotic Lactobacillus rhamnosus supplementation (PROB) on appetite regulation, growth-related markers, and microbiota diversity in zebrafish (Danio rerio) larvae, compared to a group subjected to a constant darkness photoperiod (DARK), as well as to evaluate the effects of both treatments on melatonin receptors' expression. After a 24 h treatment, both PROB and DARK conditions caused a significant increase in leptin a expression. Moreover, mRNA abundances of leptin b and proopiomelanocortin a were elevated in the PROB group, and DARK showed a similar tendency, supporting a negative regulation of appetite markers by the treatments. Moreover, both PROB and DARK also enhanced the abundances of melatonin receptors transcript (melatonin receptor 1 ba and bb) and protein (melatonin receptor 1) suggesting a potential involvement of melatonin in mediating these effects. Nevertheless, treatments did not exhibit a significant effect on the expression of most of the growth hormone/insulin-like growth factor axis genes evaluated. Finally, only the DARK condition significantly modulated gut microbiota diversity at such short time, altogether highlighting the rapid effects of this probiotic on modulating appetite regulatory and melatonin receptors' expression, without a concomitant variation of gut microbiota

    Photoperiod manipulation affects transcriptional profile of genes related to lipid metabolism and apoptosis in zebrafish (Danio rerio) larvae: potential roles of gut microbiota

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    Gut microbiota plays a fundamental role in maintaining host's health by controlling a wide range of physiological processes. Administration of probiotics and manipulation of photoperiod have been suggested as modulators of microbial composition and are currently undergoing an extensive research in aquaculture as a way to improve health and quality of harvested fish. However, our understanding regarding their effects on physiological processes is still limited. In the present study we investigated whether manipulation of photoperiod and/or probiotic administration was able to alter microbial composition in zebrafish larvae at hatching stage. Our findings show that probiotic does not elicit effects while photoperiod manipulation has a significant impact on microbiota composition. Moreover, we successfully predicted lipid biosynthesis and apoptosis to be modulated by microbial communities undergoing continuous darkness. Interestingly, expression levels of caspase 3 gene (casp3) and lipid-related genes (hnf4a, npc1l1, pparγ, srebf1, agpat4 and fitm2) were found to be significantly overexpressed in dark-exposed larvae, suggesting an increase in the occurrence of apoptotic processes and a lipid metabolism impairment, respectively (p < 0.05). Our results provide the evidence that microbial communities in zebrafish at early life stages are not modulated by a short administration of probiotics and highlight the significant effect that dark photoperiod elicits on zebrafish microbiota and potentially on health

    Conjugados poliméricos y su utilización como nanomedicinas anticancerígenas

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    Independientemente del descubrimiento de nuevos fármacos para dianas farmacológicas bien establecidas, el compromiso de la ciencia con la sociedad demanda del desarrollo de análogos macromoleculares que mejoren las posibilidades terapéuticas de los fármacos existentes aportando una mayor actividad biológica y una mayor especificidad. Se postula, cada vez con más fuerza, que la aplicación de la nanotecnología a la medicina es la clave para conseguir las mejoras necesarias tanto en diagnosis como en terapia anticancerígeno [1]. Para poder distinguirlos de otros productos biotecnológicos como proteínas y anticuerpos, los nanofármacos han sido definidos como “... sistemas complejos de escala nanométrica constituidos al menos por dos componentes, siendo uno de ellos el agente bioactivo...” [2]. Con varios conjugados polímero-proteína en el mercado y más de 11 conjugados polímero-fármaco en fase clínica, los polímeros terapéuticos pueden ser considerados como una de las primeras nanomedicinas poliméricas [3]. Es importante mencionar que aunque este artículo se centra en el uso de conjugados poliméricos como anticancerígenos, su aplicación clínica es mucho más amplia habiendo sido descritos como posibles inmunomoduladores, agentes antivíricos o fármacos para reconstitución enzimát ica entre otros [3].Independently of the discovery of new drugs for good established pharmacologic targets, the commitment of science with the society demands the development of macromolecular analogs, in order to improve the therapeutic possibilities of existing drugs, contributing to an increase on their biological activity and a greater specificity. Every time becomes more strongly the postulated that the application of nanotechnology in medicine is the key to obtain the necessary improvements in diagnosis and anticancer therapy [1]. In order to distinguish them from the other biotechnological products, such as proteins and antibodies; the nanodrugs have been defined as “… complex systems of nanometric scale, at least constituted by two components, being one of them a bioactive agent…” [2]. With several polymer-protein conjugates in the market and more than eleven polymer-drug conjugates in clinical trails; polymer therapeutics can be considered as the first polymeric nanomedicines [3]. It is important to make clear that although this article is focused on the use of polymeric conjugates as anticancerigenic agents, its clinical application is wider than. Other potential applications have been described for these nanomedicines, such as inmunomodulation, antiviral agents or drugs for enzymatic reconstruction, among others [3][email protected]

    C-reactive protein in outpatients with acute exacerbation of COPD: its relationship with microbial etiology and severity

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    BACKGROUND: C-reactive protein (CRP) measurement has proven valuable for detecting exacerbations, but its usefulness in predicting etiology remains controversial. Likewise, its potential value as a marker of severity, which is well established in patients with pneumonia, remains unproven in chronic obstructive pulmonary disease (COPD) exacerbations. METHODS: A cohort study of 118 patients with severe COPD and acute infectious exacerbations were included and followed up over 1 year. Episodes of exacerbations meeting Anthonisen's criteria type I-II were evaluated, analyzing the etiology and inflammatory response as measured by CRP in blood. RESULTS: A total of 380 episodes were recorded. Full microbiological analysis was available in 265 samples. Haemophilus influenzae was the most commonly isolated bacteria and rhinovirus the most common virus. Median CRP levels from the 265 episodes were higher in the cases with positive cultures for bacteria (58.30 mg/L, interquartile range [IQR] 21.0-28.2) than in episodes only positive for viruses (37.3 mg/L, IQR 18.6-79.1) and cases negative for any microorganism (36.4 mg/L, IQR 10.8-93.7) (P<0.014). H. influenzae and Streptococcus pneumoniae reached the highest CRP levels of 74.5 mg/L (IQR 23.9-167.9) and 74.1 mg/L (IQR 42.0-220.7), respectively. In the 380 exacerbations studied, 227 (~60%) were community-managed, while 153 (~40%) required hospital admission. In the multivariate analysis to assess the influence of inflammatory response on exacerbation severity, baseline hypercapnia (odds ratio [OR]: 2.70, 95% confidence interval [CI]: 1.46-4.9) and CRP levels >100 mg/L (OR: 4.23, 95% CI: 2.12-8.44) were independent predictors after adjustment for baseline characteristics. CONCLUSION: CRP level was higher in bacterial infections, especially when H. influenzae and S. pneumoniae were isolated. CRP values >100 mg/L were associated with a fourfold increased risk of hospital admission. Therefore, CRP blood levels may be a useful biomarker in the management of exacerbations appearing in patients with severe disease

    Pseudomonas aeruginosa antibiotic susceptibility profiles, genomic epidemiology and resistance mechanisms : a nation-wide five-year time lapse analysis

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    Pseudomonas aeruginosa healthcare-associated infections are one of the top antimicrobial resistance threats world-wide. In order to analyze the current trends, we performed a Spanish nation-wide high-resolution analysis of the susceptibility profiles, the genomic epidemiology and the resistome of P. aeruginosa over a five-year time lapse. A total of 3.180 nonduplicated P. aeruginosa clinical isolates from two Spanish nation-wide surveys performed in October 2017 and 2022 were analyzed. MICs of 13 antipseudomonals were determined by ISO-EUCAST. Multidrug resistance (MDR)/extensively drug resistance (XDR)/difficult to treat resistance (DTR)/pandrug resistance (PDR) profiles were defined following established criteria. All XDR/DTR isolates were subjected to whole genome sequencing (WGS). A decrease in resistance to all tested antibiotics, including older and newer antimicrobials, was observed in 2022 vs 2017. Likewise, a major reduction of XDR (15.2% vs 5.9%) and DTR (4.2 vs 2.1%) profiles was evidenced, and even more patent among ICU isolates [XDR (26.0% vs 6.0%) and DTR (8.9% vs 2.6%)] (p < 0.001). The prevalence of Extended-spectrum β-lactamase/carbapenemase production was slightly lower in 2022 (2.1%. vs 3.1%, p = 0.064). However, there was a significant increase in the proportion of carbapenemase production among carbapenem-resistant strains (29.4% vs 18.1%, p = 0.0246). While ST175 was still the most frequent clone among XDR, a slight reduction in its prevalence was noted (35.9% vs 45.5%, p = 0.106) as opposed to ST235 which increased significantly (24.3% vs 12.3%, p = 0.0062). While the generalized decrease in P. aeruginosa resistance, linked to a major reduction in the prevalence of XDR strains, is encouraging, the negative counterpart is the increase in the proportion of XDR strains producing carbapenemases, associated to the significant advance of the concerning world-wide disseminated hypervirulent high-risk clone ST235. Continued high-resolution surveillance, integrating phenotypic and genomic data, is necessary for understanding resistance trends and analyzing the impact of national plans on antimicrobial resistance. MSD and the Instituto de Salud Carlos III, Ministerio de Ciencia e Innovación and Unión Europea- NextGenerationEU

    Multicenter study of lumen-apposing metal stents with or without pigtail in endoscopic ultrasound-guided biliary drainage for malignant obstruction - BAMPI TRIAL: an open-label, randomized controlled trial protocol

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    Background It is unclear whether the insertion of an axis-orienting double-pigtail plastic stent (DPS) through biliary lumen-apposing meal stent (LAMS) in EUS-guided choledochoduodenostomy (CDS) improves the stent patency. The aim of this study is to determine whether this technical variant offers a clinical benefit in EUS-guided biliary drainage (BD) for the management of distal malignant biliary obstruction. Methods/design This is a multicenter open-label, randomized controlled trial with two parallel groups. Eighty-four patients with malignant biliary obstruction will undergo EUS-BD (CDS type) using LAMS in 7 tertiary hospitals in Spain and will be randomized to the LAMS and LAMS plus DPS groups. The primary endpoint is the rate of recurrent biliary obstruction, as a stent dysfunction parameter, detected during follow-up. Secondary endpoints: technical and clinical success (reduction in bilirubin > 50% within 14 days of stent placement), safety, and others (number of reinterventions, time to biliary obstruction, prognostic factors, survival rate). Discussion The BAMPI trial has been designed to determine whether the addition of a coaxial axis-orienting DPS through LAMS is superior to LAMS alone to prevent stent dysfunction

    Eligibility criteria for Menopausal Hormone Therapy (MHT): a position statement from a consortium of scientific societies for the use of MHT in women with medical conditions. MHT Eligibility Criteria Group

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    This project aims to develop eligibility criteria for menopausal hormone therapy (MHT). The tool should be similar to those already established for contraception A consortium of scientific societies coordinated by the Spanish Menopause Society met to formulate recommendations for the use of MHT by women with medical conditions based on the best available evidence. The project was developed in two phases. As a first step, we conducted 14 systematic reviews and 32 metanalyses on the safety of MHT (in nine areas: age, time of menopause onset, treatment duration, women with thrombotic risk, women with a personal history of cardiovascular disease, women with metabolic syndrome, women with gastrointestinal diseases, survivors of breast cancer or of other cancers, and women who smoke) and on the most relevant pharmacological interactions with MHT. These systematic reviews and metanalyses helped inform a structured process in which a panel of experts defined the eligibility criteria according to a specific framework, which facilitated the discussion and development process. To unify the proposal, the following eligibility criteria have been defined in accordance with the WHO international nomenclature for the different alternatives for MHT (category 1, no restriction on the use of MHT; category 2, the benefits outweigh the risks; category 3, the risks generally outweigh the benefits; category 4, MHT should not be used). Quality was classified as high, moderate, low or very low, based on several factors (including risk of bias, inaccuracy, inconsistency, lack of directionality and publication bias). When no direct evidence was identified, but plausibility, clinical experience or indirect evidence were available, "Expert opinion" was categorized. For the first time, a set of eligibility criteria, based on clinical evidence and developed according to the most rigorous methodological tools, has been defined. This will provide health professionals with a powerful decision-making tool that can be used to manage menopausal symptoms

    Biogénesis y plegamiento de proteínas de membrana

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    Todas las células, ya sean bacterias, arqueas o eucariotas están delimitadas por membranas. Las membranas biológicas están compuestas principalmente por lípidos estructurados en dos monocapas enfrentadas, por lo que también se les denomina bicapas lipídicas. La membrana, además de definir los límites tanto celulares como organulares y establecer una barrera al tráfico de moléculas de unos compartimentos a otros posee otras funciones importantes para la supervivencia celular, como el transporte selectivo, la producción de la mayoría de energía requerida para los procesos catalíticos y la transducción de señales.618/5000 All cells, whether bacteria, archaea or eukaryotes are bounded by membranes. Biological membranes are composed mainly of structured lipids in two facing monolayers, so they are also called lipid bilayers. The membrane, in addition to defining both cellular and organ limits and establishing a barrier to the traffic of molecules from one compartment to another, has other important functions for cell survival, such as selective transport, energy production required for catalytic processes and signal transduction
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