Traumatic Brain Injury Causes Endothelial Dysfunction in the Systemic Microcirculation through Arginase-1-Dependent Uncoupling of Endothelial Nitric Oxide Synthase

Endothelial dysfunction is a hallmark of many chronic diseases, including diabetes and long-term hypertension. We show that acute traumatic brain injury (TBI) leads to endothelial dysfunction in rat mesenteric arteries. Endothelial-dependent dilation was greatly diminished 24 h after TBI because of impaired nitric oxide (NO) production. The activity of arginase, which competes with endothelial NO synthase (eNOS) for the common substrate l-arginine, were also significantly increased in arteries, suggesting that arginase-mediated depletion of l-arginine underlies diminished NO production. Consistent with this, substrate restoration by exogenous application of l-arginine or inhibition of arginase recovered endothelial function. Moreover, evidence for increased reactive oxygen species production, a consequence of l-arginine starvation-dependent eNOS uncoupling, was detected in endothelium and plasma. Collectively, our findings demonstrate endothelial dysfunction in a remote vascular bed after TBI, manifesting as impaired endothelial-dependent vasodilation, with increased arginase activity, decreased generation of NO, and increased O(2)(-) production. We conclude that blood vessels have a “molecular memory” of neurotrauma, 24 h after injury, because of functional changes in vascular endothelial cells; these effects are pertinent to understanding the systemic inflammatory response that occurs after TBI even in the absence of polytrauma

Complex evolutionary history of the Mexican stoneroller Campostoma ornatum Girard, 1856 (Actinopterygii: Cyprinidae)

<p>Abstract</p> <p>Background</p> <p>Studies of the phylogeography of Mexican species are steadily revealing genetic patterns shared by different species, which will help to unravel the complex biogeographic history of the region. <it>Campostoma ornatum </it>is a freshwater fish endemic to montane and semiarid regions in northwest Mexico and southern Arizona. Its wide range of distribution and the previously observed morphological differentiation between populations in different watersheds make this species a useful model to investigate the biogeographic role of the Sierra Madre Occidental and to disentangle the actions of Pliocene tecto-volcanic processes <it>vs </it>Quaternary climatic change. Our phylogeographic study was based on DNA sequences from one mitochondrial gene (<it>cytb</it>, 1110 bp, n = 285) and two nuclear gene regions (S7 and RAG1, 1822 bp in total, n = 56 and 43, respectively) obtained from 18 to 29 localities, in addition to a morphological survey covering the entire distribution area. Such a dataset allowed us to assess whether any of the populations/lineages sampled deserve to be categorised as an evolutionarily significant unit.</p> <p>Results</p> <p>We found two morphologically and genetically well-differentiated groups within <it>C. ornatum</it>. One is located in the northern river drainages (Yaqui, Mayo, Fuerte, Sonora, Casas Grandes, Santa Clara and Conchos) and another one is found in the southern drainages (Nazas, Aguanaval and Piaxtla). The split between these two lineages took place about 3.9 Mya (CI = 2.1-5.9). Within the northern lineage, there was strong and significant inter-basin genetic differentiation and also several secondary dispersal episodes whit gene homogenization between drainages. Interestingly, three divergent mitochondrial lineages were found in sympatry in two northern localities from the Yaqui river basin.</p> <p>Conclusions</p> <p>Our results indicate that there was isolation between the northern and southern phylogroups since the Pliocene, which was related to the formation of the ancient Nazas River paleosystem, where the southern group originated. Within groups, a complex reticulate biogeographic history for <it>C. ornatum </it>populations emerges, following the taxon pulse theory and mainly related with Pliocene tecto-volcanic processes. In the northern group, several events of vicariance promoted by river or drainage isolation episodes were found, but within both groups, the phylogeographic patterns suggest the occurrence of several events of river capture and fauna interchange. The Yaqui River supports the most diverse populations of <it>C. ornatum</it>, with several events of dispersal and isolation within the basin. Based on our genetic results, we defined three ESUs within <it>C. ornatum </it>as a first attempt to promote the conservation of the evolutionary processes determining the genetic diversity of this species. They will likely be revealed as a valuable tool for freshwater conservation policies in northwest Mexico, where many environmental problems concerning the use of water have rapidly arisen in recent decades.</p

Atrasentan and renal events in patients with type 2 diabetes and chronic kidney disease (SONAR): a double-blind, randomised, placebo-controlled trial

Background: Short-term treatment for people with type 2 diabetes using a low dose of the selective endothelin A receptor antagonist atrasentan reduces albuminuria without causing significant sodium retention. We report the long-term effects of treatment with atrasentan on major renal outcomes. Methods: We did this double-blind, randomised, placebo-controlled trial at 689 sites in 41 countries. We enrolled adults aged 18–85 years with type 2 diabetes, estimated glomerular filtration rate (eGFR)25–75 mL/min per 1·73 m 2 of body surface area, and a urine albumin-to-creatinine ratio (UACR)of 300–5000 mg/g who had received maximum labelled or tolerated renin–angiotensin system inhibition for at least 4 weeks. Participants were given atrasentan 0·75 mg orally daily during an enrichment period before random group assignment. Those with a UACR decrease of at least 30% with no substantial fluid retention during the enrichment period (responders)were included in the double-blind treatment period. Responders were randomly assigned to receive either atrasentan 0·75 mg orally daily or placebo. All patients and investigators were masked to treatment assignment. The primary endpoint was a composite of doubling of serum creatinine (sustained for ≥30 days)or end-stage kidney disease (eGFR <15 mL/min per 1·73 m 2 sustained for ≥90 days, chronic dialysis for ≥90 days, kidney transplantation, or death from kidney failure)in the intention-to-treat population of all responders. Safety was assessed in all patients who received at least one dose of their assigned study treatment. The study is registered with ClinicalTrials.gov, number NCT01858532. Findings: Between May 17, 2013, and July 13, 2017, 11 087 patients were screened; 5117 entered the enrichment period, and 4711 completed the enrichment period. Of these, 2648 patients were responders and were randomly assigned to the atrasentan group (n=1325)or placebo group (n=1323). Median follow-up was 2·2 years (IQR 1·4–2·9). 79 (6·0%)of 1325 patients in the atrasentan group and 105 (7·9%)of 1323 in the placebo group had a primary composite renal endpoint event (hazard ratio [HR]0·65 [95% CI 0·49–0·88]; p=0·0047). Fluid retention and anaemia adverse events, which have been previously attributed to endothelin receptor antagonists, were more frequent in the atrasentan group than in the placebo group. Hospital admission for heart failure occurred in 47 (3·5%)of 1325 patients in the atrasentan group and 34 (2·6%)of 1323 patients in the placebo group (HR 1·33 [95% CI 0·85–2·07]; p=0·208). 58 (4·4%)patients in the atrasentan group and 52 (3·9%)in the placebo group died (HR 1·09 [95% CI 0·75–1·59]; p=0·65). Interpretation: Atrasentan reduced the risk of renal events in patients with diabetes and chronic kidney disease who were selected to optimise efficacy and safety. These data support a potential role for selective endothelin receptor antagonists in protecting renal function in patients with type 2 diabetes at high risk of developing end-stage kidney disease. Funding: AbbVie

Quality indicators in interhospital transport: Multicentre project

Indicadores de calidad; Transporte interhospitalario; Mejora de calidadQuality indicators; Interhospital transport; Quality improvementIndicadors de qualitat; Transport interhospitalari; Millora de la qualitatIntroduction Interhospital transport is carried out by variable teams in different regions of our country, and this makes quality evaluation and benchmarking complicated. Project objective: Select and define a consensual list of quality measurement that may be used by national transport units, whether specialised or not. Methods Initial set of quality indicators was proposed by coordinators (members of representative specialised transport units in Spain). Evaluation by selected transport specialists from participating units and SECIP (Society of Paediatric Intensive Care) and SENeo (Spanish Neonatology Society) work teams. Selection of definitive indicators by Delphi method according to relevance and feasibility. Results A total of 35 quality indicators were included in the initial set. Evaluation was carried out by 22 specialists from 7 transport teams. In a first round, 4 indicators were consensually included in the definitive list. Results for the rest of metrics and comments were sent to all participants, and after a second assessment, 11 other indicators reached enough consensus. After list accomplishment, a consensual final definition for every indicator was established. Conclusions Using a consensual research method, a list of 15 common indicators was obtained, which may be used by specialised transport teams in our country, and by non-specialised clinics in charge of interhospital paediatric transport. It will allow individual performance to be assessed, as well as benchmarking, in order to find improvement opportunities and ensure the highest quality during interhospital transport.Introducción El traslado interhospitalario se realiza por equipos muy diferentes en las distintas regiones de nuestro país, lo que dificultad la comparación de su calidad asistencial. Objetivo: Seleccionar y definir una lista consensuada de indicadores de calidad aplicable a todas las unidades de transporte, especializadas o no, a nivel nacional. Material y métodos Realización de una propuesta inicial de indicadores por el comité coordinador con representantes del transporte especializado de nuestro país. Valoración del listado por especialistas en transporte de las unidades participantes y los grupos de trabajo de SECIP y SENeo. Selección de los indicadores mediante el método Delphi según su relevancia y factibilidad. Resultados El listado inicial incluyó 35 posibles indicadores. Fueron valorados por 22 especialistas pertenecientes a 7 unidades de transporte. En una primera fase se eligieron por consenso 4 indicadores, que pasaron directamente al listado definitivo. Se enviaron a los encuestados los resultados del resto de indicadores y las observaciones realizadas por los participantes, y tras ello se realizó una segunda valoración, en la que alcanzaron un consenso aceptable otros 11 indicadores. Tras la elaboración del listado, se estableció de forma consensuada la definición final de cada indicador elegido. Conclusiones Utilizando un sistema de búsqueda de consenso, definimos una lista de 15 indicadores comunes, que podría ser utilizada por las unidades especializadas de nuestro país y personal asistencial no especializado que realiza traslados pediátricos. Permitirá evaluar el rendimiento individual y comparar las diferentes unidades para encontrar oportunidades de mejora y asegurar la máxima calidad durante el transporte

Exome sequencing identifies breast cancer susceptibility genes and defines the contribution of coding variants to breast cancer risk (vol 55, pg 1435, 2023)

10.1038/s41588-023-01549-xNATURE GENETICS551

X chromosome inactivation does not necessarily determine the severity of the phenotype in Rett syndrome patients

WOS: 000481590200024PubMed ID: 31427717Rett syndrome (RTT) is a severe neurological disorder usually caused by mutations in the MECP2 gene. Since the MECP2 gene is located on the X chromosome, X chromosome inactivation (XCI) could play a role in the wide range of phenotypic variation of RTT patients; however, classical methylation-based protocols to evaluate XCI could not determine whether the preferentially inactivated X chromosome carried the mutant or the wild-type allele. Therefore, we developed an allele-specific methylation-based assay to evaluate methylation at the loci of several recurrent MECP2 mutations. We analyzed the XCI patterns in the blood of 174 RTT patients, but we did not find a clear correlation between XCI and the clinical presentation. We also compared XCI in blood and brain cortex samples of two patients and found differences between XCI patterns in these tissues. However, RTT mainly being a neurological disease complicates the establishment of a correlation between the XCI in blood and the clinical presentation of the patients. Furthermore, we analyzed MECP2 transcript levels and found differences from the expected levels according to XCI. Many factors other than XCI could affect the RTT phenotype, which in combination could influence the clinical presentation of RTT patients to a greater extent than slight variations in the XCI pattern.Spanish Ministry of Health (Instituto de Salud Carlos III/FEDER) [PI15/01159]; Crowdfunding program PRECIPITA, from the Spanish Ministry of Health (Fundacion Espanola para la Ciencia y la Tecnologia); Catalan Association for Rett Syndrome; Fondobiorett; Mi Princesa RettWe thank all patients and their families who contributed to this study. The work was supported by grants from the Spanish Ministry of Health (Instituto de Salud Carlos III/FEDER, PI15/01159); Crowdfunding program PRECIPITA, from the Spanish Ministry of Health (Fundacion Espanola para la Ciencia y la Tecnologia); the Catalan Association for Rett Syndrome; Fondobiorett and Mi Princesa Rett