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1.
Arch Cardiol Mex ; 94(Supl 1): 1-74, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38648647

RESUMO

Chronic heart failure continues to be one of the main causes of impairment in the functioning and quality of life of people who suffer from it, as well as one of the main causes of mortality in our country and around the world. Mexico has a high prevalence of risk factors for developing heart failure, such as high blood pressure, diabetes, and obesity, which makes it essential to have an evidence-based document that provides recommendations to health professionals involved in the diagnosis and treatment of these patients. This document establishes the clinical practice guide (CPG) prepared at the initiative of the Mexican Society of Cardiology (SMC) in collaboration with the Iberic American Agency for the Development and Evaluation of Health Technologies, with the purpose of establishing recommendations based on the best available evidence and agreed upon by an interdisciplinary group of experts. This document complies with international quality standards, such as those described by the US Institute of Medicine (IOM), the National Institute of Clinical Excellence (NICE), the Intercollegiate Network for Scottish Guideline Development (SIGN) and the Guidelines International Network (G-I-N). The Guideline Development Group was integrated in a multi-collaborative and interdisciplinary manner with the support of methodologists with experience in systematic literature reviews and the development of CPG. A modified Delphi panel methodology was developed and conducted to achieve an adequate level of consensus in each of the recommendations contained in this CPG. We hope that this document contributes to better clinical decision making and becomes a reference point for clinicians who manage patients with chronic heart failure in all their clinical stages and in this way, we improve the quality of clinical care, improve their quality of life and reducing its complications.


La insuficiencia cardiaca crónica sigue siendo unas de las principales causas de afectación en el funcionamiento y en la calidad de vida de las personas que la presentan, así como una de las primeras causas de mortalidad en nuestro país y en todo el mundo. México tiene una alta prevalencia de factores de riesgo para desarrollar insuficiencia cardiaca, tales como hipertensión arterial, diabetes y obesidad, lo que hace imprescindible contar con un documento basado en la evidencia que brinde recomendaciones a los profesionales de la salud involucrados en el diagnóstico y el tratamiento de estos pacientes. Este documento establece la guía de práctica clínica (GPC) elaborada por iniciativa de la Sociedad Mexicana de Cardiología (SMC) en colaboración con la Agencia Iberoamericana de Desarrollo y Evaluación de Tecnologías en Salud, con la finalidad de establecer recomendaciones basadas en la mejor evidencia disponible y consensuadas por un grupo interdisciplinario y multicolaborativo de expertos. Cumple con estándares internacionales de calidad, como los descritos por el Institute of Medicine de los Estados Unidos de América (IOM), el National Institute of Clinical Excellence (NICE) del Reino Unido, la Intercollegiate Network for Scottish Guideline Development (SIGN) de Escocia y la Guidelines International Network (G-I-N). El grupo de desarrollo de la guía se integró de manera interdisciplinaria con el apoyo de metodólogos con experiencia en revisiones sistemáticas de la literatura y en el desarrollo de GPC. Se llevó a cabo y se condujo metodología de panel Delphi modificado para lograr un nivel de consenso adecuado en cada una de las recomendaciones contenidas en esta GPC. Esperamos que este documento contribuya para la mejor toma de decisiones clínicas y se convierta en un punto de referencia para los clínicos que manejan pacientes con insuficiencia cardiaca crónica en todas sus etapas clínicas, y de esta manera logremos mejorar la calidad en la atención clínica, aumentar la calidad de vida de los pacientes y disminuir las complicaciones de la enfermedad.

2.
PLoS Genet ; 20(3): e1011193, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38489392

RESUMO

Cell Competition is a process by which neighboring cells compare their fitness. As a result, viable but suboptimal cells are selectively eliminated in the presence of fitter cells. In the early mammalian embryo, epiblast pluripotent cells undergo extensive Cell Competition, which prevents suboptimal cells from contributing to the newly forming organism. While competitive ability is regulated by MYC in the epiblast, the mechanisms that contribute to competitive fitness in this context are largely unknown. Here, we report that P53 and its pro-apoptotic targets PUMA and NOXA regulate apoptosis susceptibility and competitive fitness in pluripotent cells. PUMA is widely expressed specifically in pluripotent cells in vitro and in vivo. We found that P53 regulates MYC levels in pluripotent cells, which connects these two Cell Competition pathways, however, MYC and PUMA/NOXA levels are independently regulated by P53. We propose a model that integrates a bifurcated P53 pathway regulating both MYC and PUMA/NOXA levels and determines competitive fitness.


Assuntos
Competição entre as Células , Proteínas Proto-Oncogênicas c-bcl-2 , Proteína Supressora de Tumor p53 , Animais , Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Competição entre as Células/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Camundongos
3.
Mar Environ Res ; 196: 106432, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38457908

RESUMO

Bioaccumulation patterns of heavy metals (Pb, Cd, Cr, Ni, Fe and Cu) and organic (priority and emerging) pollutants, in combination with stable isotope analysis (SIA), were assessed in muscle and liver of three tuna species from the Gulf of Cadiz (Atlantic bluefin tuna, Thunnus thynnus; Atlantic bonito, Sarda sarda, and skipjack tuna, Katsuwonus pelamis). SIA and contaminant (heavy metal and organic) profiles separately discriminated between species. There was no significant overlap between the trophic niches estimated from isotopic data, suggesting that there are diet differences which may determine differential bioaccumulation patterns. The levels of heavy metals and persistent organic pollutants in muscle of all the individuals analyzed were below the allowable limits established by the current legislation. Concentrations of most contaminants were higher in liver than in muscle, underlining the powerful detoxifying capacity of the liver in tunas. In addition to diet, other factors such as size and age (exposure time to environmental chemicals) explain differences in pollutant accumulation patterns in tissues between species, each with varying degrees of involvement depending on the pollutant class. Our results show that combining contaminant profile data with trophic features based on SIA may help understand pollutant bioaccumulation patterns in upper levels of marine food webs.


Assuntos
Poluentes Ambientais , Metais Pesados , Humanos , Animais , Atum , Metais Pesados/análise , Isótopos/análise , Cadeia Alimentar
4.
PLoS One ; 19(3): e0289395, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38437228

RESUMO

The detection of temperature by the human sensory system is life-preserving and highly evolutionarily conserved. Platelets are sensitive to temperature changes and are activated by a decrease in temperature, akin to sensory neurons. However, the molecular mechanism of this temperature-sensing ability is unknown. Yet, platelet activation by temperature could contribute to numerous clinical sequelae, most importantly to reduced quality of ex vivo-stored platelets for transfusion. In this multidisciplinary study, we present evidence for the expression of the temperature-sensitive ion channel transient receptor potential cation channel subfamily member 8 (TRPM8) in human platelets and precursor cells. We found the TRPM8 mRNA and protein in MEG-01 cells and platelets. Inhibition of TRPM8 prevented temperature-induced platelet activation and shape change. However, chemical agonists of TRPM8 did not seem to have an acute effect on platelets. When exposing platelets to below-normal body temperature, we detected a cytosolic calcium increase which was independent of TRPM8 but was completely dependent on the calcium release from the endoplasmic reticulum. Because of the high interindividual variability of TRPM8 expression, a population-based approach should be the focus of future studies. Our study suggests that the cold response of platelets is complex and TRPM8 appears to play a role in early temperature-induced activation of platelets, while other mechanisms likely contribute to later stages of temperature-mediated platelet response.


Assuntos
Cálcio , Canais de Cátion TRPM , Humanos , Temperatura Baixa , Cálcio da Dieta , Retículo Endoplasmático , Células Receptoras Sensoriais , Canais de Cátion TRPM/genética , Proteínas de Membrana
5.
bioRxiv ; 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38370737

RESUMO

Protein S (PS), the critical plasma cofactor for the anticoagulants tissue factor (TF) pathway inhibitor (TFPI) and activated protein C (APC), circulates in two functionally distinct pools: free (anticoagulant) or bound to complement component 4b-binding protein (C4BP) (anti-inflammatory). Acquired free PS deficiency is detected in several viral infections, but its cause is unclear. Here, we identified a shear-dependent interaction between PS and von Willebrand Factor (VWF) by mass spectrometry. Consistently, plasma PS and VWF comigrated in both native and agarose gel electrophoresis. The PS/VWF interaction was blocked by TFPI but not APC, suggesting an interaction with the C-terminal sex hormone binding globulin (SHBG) region of PS. Microfluidic systems, mimicking arterial laminar flow or disrupted turbulent flow, demonstrated that PS stably binds VWF as VWF unfolds under turbulent flow. PS/VWF complexes also localized to platelet thrombi under laminar arterial flow. In thrombin generation-based assays, shearing plasma decreased PS activity, an effect not seen in the absence of VWF. Finally, free PS deficiency in COVID-19 patients, measured using an antibody that binds near the C4BP binding site in SHBG, correlated with changes in VWF, but not C4BP, and with thrombin generation. Our data suggest that PS binds to a shear-exposed site on VWF, thus sequestering free PS and decreasing its anticoagulant activity, which would account for the increased thrombin generation potential. As many viral infections present with free PS deficiency, elevated circulating VWF, and increased vascular shear, we propose that the PS/VWF interaction reported here is a likely contributor to virus-associated thrombotic risk.

7.
Cureus ; 15(11): e48561, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38073928

RESUMO

Neuroendocrine tumors comprise a range of neoplasms with varying spectra of origin, biological activity, clinical features, and histological appearance. In this case report, we present a pregnant 33-year-old female who was brought to the emergency department (ED) complaining of acute right iliac fossa pain accompanied by diarrhea and vomiting. Initial management showed no improvement. Lab results, clinical history, and physical exam were suggestive of appendicitis, so an exploratory minimally invasive laparoscopic exam was performed. The histopathological analysis of the excised appendix confirmed the diagnosis of acute appendicitis and periappendicitis. Incidentally, a 0.6 cm neuroendocrine tumor (carcinoid tumor) was identified on the wall of the appendiceal tip. The tumor extended at multiple points into the subserosal fat, and the serous surface and the resection margin were negative for the tumor. After seven days of the initial procedure, the patient presented with abdominal pain and a fever. An abdominal ultrasound was performed, revealing the presence of free fluid. A second exploratory laparoscopy revealed adhesions between the fallopian tubes and cecum, as well as a collection of purulent fluid. The management consisted of adhesiolysis, cavity lavage, and drainage, along with antibiotic therapy, pain management, and close monitoring of the mother's and fetus's status. The patient had a successful recovery and was discharged home a week after surgery. She gave birth to a full-term, healthy baby and remains free of tumor relapse. This case highlights the importance of obtaining histopathological interpretation of any extracted tissue during surgery. Guidelines regarding the management of carcinoids during pregnancy are not available, and when considering surgical intervention, an open or laparoscopic approach must be carefully evaluated.

8.
Inorg Chem ; 62(48): 19421-19432, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-37988130

RESUMO

The ability of the imine PyCH═N-CH2Py (Py = 2-pyridyl, bpi) to behave as a heteroditopic ligand, which is suitable for creating two separate compartments to host metals in different oxidation states, has been developed by studying the reactions of the mixed-valence complexes [(cod)M-Ι(µ-bpi)MΙ(cod)] (M = Rh, Ir) with [M'(Cl)2(PPh3)2] (M' = Pd, Ni). The results depend on the molar ratio of the reagents used (1:1 or 1:2) to give the heterometallic complexes {d10-M',d8-M}-[(PPh3)(Cl)M'0(µ-bpi)MΙ(cod)] (Pd,Rh, 4; Pd,Ir, 5; Ni,Rh, 8; Ni,Ir, 9) and the two-electron mixed-valent compounds [(PPh3)(Cl)M'0(µ-bpi)M'ΙΙ(Cl)] (M' = Ni, 10; Pd, 11), respectively. A redox process occurs in the replacement of the low-valent [(cod)M-I] fragment, whereas the exchange of the [(cod)MI] fragment is redox-neutral. The metal with a d8 configuration in the products exhibits a square-planar geometry coordinated to two (Rh/Ir) or three (Ni/Pd) nitrogen atoms of the bridging bpi ligand. Conversely, the metal with a d10 configuration adopts trigonal-planar geometries, π-bonded to the imine C═N bond. The isolated complexes 4/5 and 10/11, along with the hypothetical heterometallic Pd,Ni compound (12), were studied by DFT methods. Additionally, the T-shaped moiety 'M'ΙΙ(PPh3)(Cl)(η1-CH-N(bpi))', stabilized by a secondary γ-agostic interaction, and the 'M'II(Cl)(κ3N-bpi)' fragment was found to be accessible redoxomers of complexes 10 and 11 by DFT calculations.

9.
BMJ Ment Health ; 26(1)2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37907332

RESUMO

QUESTION: We compared the effectiveness of different types of parenting interventions based on an a priori taxonomy, and the impact of waitlists versus treatment as usual (TAU), in reducing child internalising problems. STUDY SELECTION AND ANALYSIS: We conducted a systematic review and network meta-analysis of published and unpublished randomised controlled trials (RCTs) until 1 October 2022 that investigated parenting interventions with children younger than 4 years. EXCLUSION CRITERIA: studies with children born preterm, with intellectual disabilities, or families receiving support for current abuse, neglect, and substance misuse. We assessed the certainty of evidence using the Confidence in Network Meta-Analysis framework. We used random-effects network meta-analysis to estimate standardised mean differences (SMDs) with 95% credible intervals (CrIs). FINDINGS: Of 20 520 citations identified, 59 RCTs (18 349 participants) were eligible for the network meta-analysis. Parenting interventions focusing on the dyadic relationship (SMD: -0.26, 95% CrI: -0.43 to -0.08) and those with mixed focus (-0.09, -0.17 to -0.02) were more effective in reducing internalising problems than TAU at the first time point available. All interventions were more effective than waitlist, which increased the risk of internalising problems compared with TAU (0.36, 0.19 to 0.52). All effects attenuated at later follow-ups. Most studies were rated as with 'high risk' or 'some concerns' using the Risk of Bias Assessment Tool V.2. There was no strong evidence of effect modification by theoretically informed components or modifiers. CONCLUSIONS: We found preliminary evidence that relationship-focused and mixed parenting interventions were effective in reducing child internalising problems, and the waitlist comparator increased internalising problems with implications for waiting times between referral and support. Considering the high risk of bias of most studies included, the findings from this meta-analysis should be interpreted with caution. PROSPERO registration number CRD42020172251.


Assuntos
Poder Familiar , Recém-Nascido , Humanos , Criança , Adolescente , Metanálise em Rede , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Dalton Trans ; 52(37): 13216-13228, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37665066

RESUMO

The transition metal frustrated Lewis pair compounds [(Cym)M(κ3S,P,N-HL1)][SbF6] (Cym = η6-p-MeC6H4iPr; H2L1 = N-(p-tolyl)-N'-(2-diphenylphosphanoethyl)thiourea; M = Ru (5), Os (6)) have been prepared from the corresponding dimer [{(Cym)MCl}2(µ-Cl)2] and H2L1 by successive chloride abstraction with NaSbF6 and AgSbF6 and NH deprotonation with NaHCO3. Complexes 5 and 6 and the previously reported phosphano-guanidino compounds [(Cym)M(κ3P,N,N'-HL2)][SbF6] [H2L2 = N,N'-bis(p-tolyl)-N''-(2-diphenylphosphanoethyl) guanidine; M = Ru (7), Os (8)] and pyridinyl-guanidino compounds [(Cym)M(κ3N,N',N''-HL3)][SbF6] [H2L3 = N,N'-bis(p-tolyl)-N''-(2-pyridinylmethyl) guanidine; M = Ru (9), Os (10)] heterolytically activate H2 in a reversible manner affording the hydrido complexes [(Cym)MH(H2L)][SbF6] (H2L = H2L1; M = Ru (11), Os (12); H2L = H2L2; M = Ru (13), Os (14); H2L = H2L3; M = Ru (15), Os (16)). DFT calculations carried out on the hydrogenation of complex 7 support an FLP mechanism for the process. Heating 9 and 10 in methanol yields the orthometalated complexes [(Cym)M(κ3N,N',C-H2L3-H)][SbF6] (M = Ru (17), Os (18)). The phosphano-guanidino complex 7 activates deuterated water in a reversible fashion, resulting in the gradual deuteration of the three cymene methyl protons through sequential C(sp3)-H bond activation. From DFT calculations, a metal-ligand cooperative reversible mechanism that involves the O-H bond activation and the formation of an intermediate methylene cyclohexenyl complex has been proposed. Complexes 5-10 catalyse the hydrogenation of the CC double bond of styrene and a range of acrylates, the CO bond of acetophenone and the CN bond of N-benzylideneaniline and quinoline. The CC double bond of methyl acrylate adds to catalyst 9, affording complex 19 in which a new ligand exhibiting a fac κ3N,N',C coordination mode has been incorporated.

11.
Science ; 381(6661): eadh5207, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37651538

RESUMO

Apolipoprotein B (apoB)-lipoproteins initiate and promote atherosclerotic cardiovascular disease. Plasma tissue plasminogen activator (tPA) activity is negatively associated with atherogenic apoB-lipoprotein cholesterol levels in humans, but the mechanisms are unknown. We found that tPA, partially through the lysine-binding site on its Kringle 2 domain, binds to the N terminus of apoB, blocking the interaction between apoB and microsomal triglyceride transfer protein (MTP) in hepatocytes, thereby reducing very-low-density lipoprotein (VLDL) assembly and plasma apoB-lipoprotein cholesterol levels. Plasminogen activator inhibitor 1 (PAI-1) sequesters tPA away from apoB and increases VLDL assembly. Humans with PAI-1 deficiency have smaller VLDL particles and lower plasma levels of apoB-lipoprotein cholesterol. These results suggest a mechanism that fine-tunes VLDL assembly by intracellular interactions among tPA, PAI-1, and apoB in hepatocytes.


Assuntos
Apolipoproteínas B , Aterosclerose , Hepatócitos , Lipoproteínas VLDL , Inibidor 1 de Ativador de Plasminogênio , Ativador de Plasminogênio Tecidual , Humanos , Apolipoproteínas B/sangue , Aterosclerose/sangue , Aterosclerose/metabolismo , Hepatócitos/metabolismo , Lipoproteínas VLDL/metabolismo , Inibidor 1 de Ativador de Plasminogênio/sangue , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Ativador de Plasminogênio Tecidual/metabolismo , Animais , Camundongos , Camundongos Endogâmicos C57BL
12.
Chemistry ; 29(52): e202301438, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37402228

RESUMO

Neutral [X-{Ir2 }-{Ir2 }-X] (X=Cl, Br, SCN, I) and dicationic [L-{Ir2 }-{Ir2 }-L]2+ (L=MeCN, Me2 CO) tetrametallic iridium chains made by connecting two dinuclear {Ir2 } units ({Ir2 }=[Ir2 (µ-OPy)2 (CO)4 ], OPy=2-pyridonate) by an iridium-iridium bond are described. The complexes exhibit fractional averaged oxidation states of +1.5 and electronic delocalization along the metallic chain. While the axial ligands do not significantly affect the metal-metal bond lengths, the metallic chain has a significant impact on the iridium-L/X bond distances. The complexes show free rotation around the unsupported iridium-iridium bond in solution, with a low-energy transition state for the chloride chain. The absorption spectra of these complexes show characteristic bands at 438-504 nm, which can be fine-tuned by varying the terminal capping ligands.

13.
Plants (Basel) ; 12(13)2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37447105

RESUMO

According to the EU, the global consumption of biomass, fossil fuels, metals, and minerals is expected to double by 2050, while waste will increase by 70%. In this context, the Circular Economy Action Plan (CEAP) intends to integrate development and sustainability. In this regard, tailored biofertilizers based on plant growth-promoting bacteria (PGPB) can improve plant yield with fewer inputs. In our project, an autochthonous halophyte of the Andalusian marshes, namely Mesembryanthemum crystallinum, was selected for its interest as a source of pharmaceuticals and nutraceuticals. The aim of this work was to use a culturomics approach for the isolation of specific PGPB and endophytes able to promote plant growth and, eventually, modulate the metabolome of the plant. For this purpose, a specific culture medium based on M. crystallinum biomass, called Mesem Agar (MA), was elaborated. Bacteria of three compartments (rhizosphere soil, root endophytes, and shoot endophytes) were isolated on standard tryptone soy agar (TSA) and MA in order to obtain two independent collections. A higher number of bacteria were isolated on TSA than in MA (47 vs. 37). All the bacteria were identified, and although some of them were isolated in both media (Pseudomonas, Bacillus, Priestia, Rosellomorea, etc.), either medium allowed the isolation of specific members of the M. crystallinum microbiome such as Leclercia, Curtobacterium, Pantoea, Lysinibacillus, Mesobacillus, Glutamicibacter, etc. Plant growth-promoting properties and extracellular degrading activities of all the strains were determined, and distinct patterns were found in both media. The three best bacteria of each collection were selected in order to produce two different consortia, whose effects on seed germination, root colonization, plant growth and physiology, and metabolomics were analyzed. Additionally, the results of the plant metabolome revealed a differential accumulation of several primary and secondary metabolites with pharmaceutical properties. Overall, the results demonstrated the feasibility of using "low cost media" based on plant biomass to carry out a culturomics approach in order to isolate the most suitable bacteria for biofertilizers. In this way, a circular model is established in which bacteria help plants to grow, and, in turn, a medium based on plant wastes supports bacterial growth at low prices, which is the reason why this approach can be considered within the model of "circular agronomy".

14.
Biophys J ; 122(18): 3738-3748, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37434354

RESUMO

Upon vascular injury, platelets form a hemostatic plug by binding to the subendothelium and to each other. Platelet-to-matrix binding is initially mediated by von Willebrand factor (VWF) and platelet-to-platelet binding is mediated mainly by fibrinogen and VWF. After binding, the actin cytoskeleton of a platelet drives its contraction, generating traction forces that are important to the cessation of bleeding. Our understanding of the relationship between adhesive environment, F-actin morphology, and traction forces is limited. Here, we examined F-actin morphology of platelets attached to surfaces coated with fibrinogen and VWF. We identified distinct F-actin patterns induced by these protein coatings and found that these patterns were identifiable into three classifications via machine learning: solid, nodular, and hollow. We observed that traction forces for platelets were significantly higher on VWF than on fibrinogen coatings and these forces varied by F-actin pattern. In addition, we analyzed the F-actin orientation in platelets and noted that their filaments were more circumferential when on fibrinogen coatings and having a hollow F-actin pattern, while they were more radial on VWF and having a solid F-actin pattern. Finally, we noted that subcellular localization of traction forces corresponded to protein coating and F-actin pattern: VWF-bound, solid platelets had higher forces at their central region while fibrinogen-bound, hollow platelets had higher forces at their periphery. These distinct F-actin patterns on fibrinogen and VWF and their differences in F-actin orientation, force magnitude, and force localization could have implications in hemostasis, thrombus architecture, and venous versus arterial thrombosis.


Assuntos
Hemostáticos , Fator de von Willebrand , Fator de von Willebrand/metabolismo , Fibrinogênio/metabolismo , Plaquetas/metabolismo , Actinas/metabolismo , Tração , Glicoproteínas da Membrana de Plaquetas/metabolismo , Hemostáticos/metabolismo , Citoesqueleto de Actina/metabolismo
15.
bioRxiv ; 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37502986

RESUMO

Platelets are sensitive to temperature changes and akin to sensory neurons, are activated by a decrease in temperature. However, the molecular mechanism of this temperature-sensing ability is unknown. Yet, platelet activation by temperature could contribute to numerous clinical sequelae, most importantly to reduced quality of ex vivo-stored platelets for transfusion. In this interdisciplinary study, we present evidence for the expression of the temperature-sensitive ion channel transient receptor potential cation channel subfamily member 8 (TRPM8) in human platelets and precursor cells. We found the TRPM8 mRNA and protein in MEG-01 cells and platelets. Inhibition of TRPM8 prevented temperature-induced platelet activation and shape change. However, chemical agonists of TRPM8 did not seem to have an acute effect on platelets. When exposing platelets to below-normal body temperature, we detected a cytosolic calcium increase which was independent of TRPM8 but was completely dependent on the calcium release from the endoplasmic reticulum. Because of the high interindividual variability of TRPM8 expression, a population-based approach should be the focus of future studies. Our study suggests that the cold response of platelets is complex and TRPM8 appears to play a role in early temperature-induced activation of platelets, while other mechanisms likely contribute to later stages of temperature-mediated platelet response.

16.
Blood ; 142(13): 1156-1166, 2023 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-37506337

RESUMO

von Willebrand factor (VWF) mediates primary hemostasis and thrombosis in response to hydrodynamic forces. We previously showed that high shear promoted self-association of VWF into hyperadhesive strands, which can be attenuated by high-density lipoprotein (HDL) and apolipoprotein A-I. In this study, we show that low-density lipoprotein (LDL) binds VWF under shear and enhances self-association. Vortexing VWF in tubes resulted in its loss from the solution and deposition onto tube surfaces, which was prevented by HDL. At a stabilizing HDL concentration of 1.2 mg/mL, increasing concentrations of LDL progressively increased VWF loss, the effect correlating with the LDL-to-HDL ratio and not the absolute concentration of the lipoproteins. Similarly, HDL diminished deposition of VWF in a post-in-channel microfluidic device, whereas LDL increased both the rate and extent of strand deposition, with both purified VWF and plasma. Hypercholesterolemic human plasma also displayed accelerated VWF accumulation in the microfluidic device. The initial rate of accumulation correlated linearly with the LDL-to-HDL ratio. In Adamts13-/- and Adamts13-/-LDLR-/- mice, high LDL levels enhanced VWF and platelet adhesion to the myocardial microvasculature, reducing cardiac perfusion, impairing systolic function, and producing early signs of cardiomyopathy. In wild-type mice, high plasma LDL concentrations also increased the size and persistence of VWF-platelet thrombi in ionophore-treated mesenteric microvessels, exceeding the accumulation seen in similarly treated ADAMTS13-deficient mice that did not receive LDL infusion. We propose that targeting the interaction of VWF with itself and with LDL may improve the course of thrombotic microangiopathies, atherosclerosis, and other disorders with defective microvascular circulation.


Assuntos
Trombose , Fator de von Willebrand , Camundongos , Humanos , Animais , Fator de von Willebrand/metabolismo , Lipoproteínas LDL , Trombose/metabolismo , Hemostasia , Adesividade Plaquetária , Proteína ADAMTS13
17.
Arterioscler Thromb Vasc Biol ; 43(6): 1041-1053, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37128919

RESUMO

BACKGROUND: In reperfused myocardial infarction, VWF (von Willebrand factor)-mediated platelet adhesion contributes to impaired microvascular reflow and possibly also to postmyocardial infarction inflammation. We hypothesized that postischemic thromboinflammatory processes are worsened by elevated LDL (low-density lipoprotein) cholesterol. METHODS: Myocardial ischemia-reperfusion or sham procedure was performed in wild-type mice and hyperlipidemic mice deficient for the LDL receptor and Apobec-1 (apolipoprotein-B mRNA editing enzyme catalytic polypeptide-1; DKO [double knockout]). DKO subgroups were treated with N-acetylcysteine, which inhibits pro-adhesive VWF multimers or with recombinant ADAMTS13 (a disintegrin and metalloproteinase with thrombospondin motifs-13), which enzymatically cleaves endothelial surface-associated VWF. Myocardial contrast echocardiography perfusion imaging and molecular imaging for VWF, platelet glycoprotein Ibα, and leukocyte CD18 (cluster of differentiation) were performed 30 minutes post-reperfusion. Histology, infarct sizing, and echocardiography were performed at 1.5 or 72 hours; late echocardiography was performed at day 21. RESULTS: After ischemia-reperfusion, DKO compared with wild-type mice had ≈2-fold higher (P<0.05) risk area signal for microvascular platelet adhesion, VWF, and CD18; greater impairment in microvascular reflow, and 2-fold larger infarct size. Treatment of DKO mice with N-acetylcysteine and ADAMTS13 reduced molecular imaging signal for microvascular platelet adhesion, VWF, and CD18; improved early microvascular reflow; and reduced eventual infarct size. ADAMTS13 suppressed the postmyocardial infarction neutrophil and monocyte infiltration, enhanced the time-dependent recovery of left ventricular systolic function, and prevented late left ventricular remodeling. CONCLUSIONS: In reperfused myocardial infarction, elevated LDL cholesterol promotes thromboinflammation through excess microvascular endothelial VWF and platelet adhesion, resulting in less microvascular reflow and larger infarct size. In the presence of elevated LDL cholesterol, therapies that suppress endothelial-associated VWF can promote recovery of left ventricular function and protect against remodeling.


Assuntos
Infarto do Miocárdio , Tromboinflamação , Animais , Camundongos , Acetilcisteína , Proteína ADAMTS13/genética , LDL-Colesterol , Inflamação , Isquemia , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/genética , Fator de von Willebrand/genética
18.
Biol Direct ; 18(1): 22, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37161421

RESUMO

Synapse diversity has been described from different perspectives, ranging from the specific neurotransmitters released, to their diverse biophysical properties and proteome profiles. However, synapse diversity at the transcriptional level has not been systematically identified across all synapse populations in the brain. To quantify and identify specific synaptic features of neuronal cell types we combined the SynGO (Synaptic Gene Ontology) database with single-cell RNA sequencing data of the mouse neocortex. We show that cell types can be discriminated by synaptic genes alone with the same power as all genes. The cell type discriminatory power is not equally distributed across synaptic genes as we could identify functional categories and synaptic compartments with greater cell type specific expression. Synaptic genes, and specific SynGO categories, belonged to three different types of gene modules: gradient expression over all cell types, gradient expression in selected cell types and cell class- or type-specific profiles. This data provides a deeper understanding of synapse diversity in the neocortex and identifies potential markers to selectively identify synapses from specific neuronal populations.


Assuntos
Encéfalo , Redes Reguladoras de Genes , Animais , Camundongos
19.
Bol Med Hosp Infant Mex ; 80(2): 122-128, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37155720

RESUMO

BACKGROUND: Acute recurrent pancreatitis (ARP) and chronic pancreatitis (CP) are infrequent clinical entities in pediatric patients, as less than 8% of the literature mentions this population. This study aimed to describe the clinical and paraclinical profile, and the etiology related to patients with ARP and CP attended at a tertiary-level healthcare institute in Mexico. METHODS: We conducted a retrospective study from medical records of patients with ARP and CP attended between 2010 and 2020, analyzing the clinical characteristics, imaging studies, and the etiology associated with each patient. RESULTS: We analyzed 25 patients: 17 were diagnosed with ARP, and eight with CP. The main etiology identified was an anatomical alteration of the pancreatic duct (32%); pancreas divisum was the most prevalent condition. In 48% of the population, the etiology was not identified. The group with CP was higher in frequency for calcifications and dilation of the pancreatic duct (p < 0.005) compared to the ARP group. CONCLUSIONS: The main etiology for ARP and CP was an anatomical alteration of the pancreatic duct; however, in almost half of the cases, no established cause was identified. Although comparing our results with those offered by large cohorts such as the INSPPIRE group can be complex, we found relevant similarities. Currently, the data obtained from this first descriptive study are the foundation for future research in the field of Mexican pediatric pancreatology.


INTRODUCCIÓN: La pancreatitis aguda recurrente (PAR) y crónica (PC) son entidades poco frecuentes en la edad pediátrica; sin embargo, menos del 8% de la literatura hace referencia a esta población. El objetivo de este estudio fue describir el perfil clínico, paraclínico y etiologías vinculadas en los pacientes con PAR y PC atendidos en una institución de tercer nivel de atención en México. MÉTODOS: Se realizó un estudio retrospectivo de los expedientes de los pacientes con PAR y PC atendidos entre 2010 a 2020, analizando las características clínicas, estudios de imagen y etiologías asociadas en cada uno de los pacientes. RESULTADOS: Se analizaron 25 pacientes, 17 con diagnóstico de PAR y ocho con PC. La principal etiología identificada correspondió a las alteraciones anatómicas del conducto pancreático (32%); el páncreas divisum fue la entidad más prevalente. En el 48% de la población no se pudo identificar una etiología. El grupo con PC presentó mayor frecuencia de calcificaciones y dilatación ductal pancreática (p < 0.005) en comparación al grupo de PAR. CONCLUSIONES: La principal etiología de PAR y PC identificada en nuestro estudio corresponde a las alteraciones anatómicas del conducto pancreático; sin embargo, en casi la mitad de los casos, no se tiene una causa establecida. Aunque es complicado comparar nuestros resultados con los ofrecidos por las grandes cohortes del grupo INSPPIRE, sí encontramos similitudes relevantes. Los datos obtenidos en este primer estudio descriptivo son la base para futuras investigaciones en el ámbito de la pancreatología pediátrica mexicana.


Assuntos
Pancreatite Crônica , Humanos , Criança , Estudos Retrospectivos , México/epidemiologia , Doença Aguda , Pancreatite Crônica/epidemiologia , Pancreatite Crônica/etiologia
20.
Antioxidants (Basel) ; 12(5)2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37237989

RESUMO

Adolescence is a period during which body composition changes deeply. Selenium (Se) is an excellent antioxidant trace element related to cell growth and endocrine function. In adolescent rats, low Se supplementation affects adipocyte development differently depending on its form of administration (selenite or Se nanoparticles (SeNPs). Despite this effect being related to oxidative, insulin-signaling and autophagy processes, the whole mechanism is not elucidated. The microbiota-liver-bile salts secretion axis is related to lipid homeostasis and adipose tissue development. Therefore, the colonic microbiota and total bile salts homeostasis were explored in four experimental groups of male adolescent rats: control, low-sodium selenite supplementation, low SeNP supplementation and moderate SeNPs supplementation. SeNPs were obtained by reducing Se tetrachloride in the presence of ascorbic acid. Supplementation was received orally through water intake; low-Se rats received twice more Se than control animals and moderate-Se rats tenfold more. Supplementation with low doses of Se clearly affected anaerobic colonic microbiota profile and bile salts homeostasis. However, these effects were different depending on the Se administration form. Selenite supplementation primarily affected liver by decreasing farnesoid X receptor hepatic function, leading to the accumulation of hepatic bile salts together to increase in the ratio Firmicutes/Bacteroidetes and glucagon-like peptide-1 (GLP-1) secretion. In contrast, low SeNP levels mainly affected microbiota, moving them towards a more prominent Gram-negative profile in which the relative abundance of Akkermansia and Muribaculaceae was clearly enhanced and the Firmicutes/Bacteroidetes ratio decreased. This bacterial profile is directly related to lower adipose tissue mass. Moreover, low SeNP administration did not modify bile salts pool in serum circulation. In addition, specific gut microbiota was regulated upon administration of low levels of Se in the forms of selenite or SeNPs, which are properly discussed. On its side, moderate-SeNPs administration led to great dysbiosis and enhanced the abundance of pathogenic bacteria, being considered toxic. These results strongly correlate with the deep change in adipose mass previously found in these animals, indicating that the microbiota-liver-bile salts axis is also mechanistically involved in these changes.

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