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1.
Development ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38856078

RESUMO

Embryonic development is a complex and dynamic process that unfolds over time and involves the production and diversification of increasing numbers of cells. The impact of developmental time on the formation of the central nervous system is well-documented, with evidence showing that time plays a critical role in establishing the identity of neuronal subtypes. However, the study of how time translates into genetic instructions driving cell fate is limited by the scarcity of suitable experimental tools. We introduce BirthSeq, a new method for isolating and analyzing cells based on their birth date. This innovative technique allows for in vivo labeling of cells, isolation via FACS, and analysis using high-throughput techniques. We tuned up BirthSeq in developmental organs across three vertebrate species (mouse, chick, and gecko), and fully made use of it for single-cell RNA sequencing and novel spatially resolved transcriptomic approaches in mouse and chick, respectively. Overall, BirthSeq provides a versatile tool for studying virtually any tissue in different vertebrate organism, helping to fill the necessity in developmental biology research by targeting cells and their temporal cues.

2.
Sensors (Basel) ; 24(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38610318

RESUMO

Sound classification plays a crucial role in enhancing the interpretation, analysis, and use of acoustic data, leading to a wide range of practical applications, of which environmental sound analysis is one of the most important. In this paper, we explore the representation of audio data as graphs in the context of sound classification. We propose a methodology that leverages pre-trained audio models to extract deep features from audio files, which are then employed as node information to build graphs. Subsequently, we train various graph neural networks (GNNs), specifically graph convolutional networks (GCNs), GraphSAGE, and graph attention networks (GATs), to solve multi-class audio classification problems. Our findings underscore the effectiveness of employing graphs to represent audio data. Moreover, they highlight the competitive performance of GNNs in sound classification endeavors, with the GAT model emerging as the top performer, achieving a mean accuracy of 83% in classifying environmental sounds and 91% in identifying the land cover of a site based on its audio recording. In conclusion, this study provides novel insights into the potential of graph representation learning techniques for analyzing audio data.

3.
Biochem Biophys Res Commun ; 524(4): 1030-1036, 2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32063359

RESUMO

The hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are encoded by a family of four genes (HCN1-4). All isoforms are expressed in the heart, HCN4 being the most abundant in the sinoatrial node (SAN). HCN channels are responsible for the "funny" current (If) associated with the generation and autonomic control of the diastolic depolarization phase of cardiac action potential. In this work we performed a proteomic analysis of HCN4 transfected in HEK293 cells. Most of the identified proteins in the HCN4 network belonged to mitochondria. The subcellular localization of HCN channels was predicted in plasma membrane, mitochondria and nucleus. Experimentally, HCN2 (full-length, truncated), HCN3 (full-length, truncated) and HCN4 (truncated) were detected in rat heart mitochondria by immunoblotting. If sensitive to ZD7288, was recorded by patch-clamp in mitoplasts from cardiomyocytes. Mitochondrial membrane potential (ΔΨm) assessment in H9c2 cells revealed that ZD7288 induced almost 50% higher hyperpolarization respect to control at 30 min. Furthermore, ZD7288 reduced oxygen consumption attributed to ATP synthesis in H9c2 cells. In conclusion, we identify for the first time functional HCN channels in mammalian cardiac mitochondria and demonstrate their impact on ΔΨm and respiration.


Assuntos
Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Potencial da Membrana Mitocondrial , Mitocôndrias Cardíacas/metabolismo , Consumo de Oxigênio , Animais , Linhagem Celular , Células HEK293 , Humanos , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/análise , Camundongos Endogâmicos BALB C , Miócitos Cardíacos/metabolismo , Ratos Wistar
4.
Electrophoresis ; 41(20): 1776-1783, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31267584

RESUMO

Rosmarinus officinalis L. (Lamiaceae) is an aromatic plant widely popular mainly due to its uses in traditional medicine as an anti-inflammatory, diuretic and antimicrobial, as well as in the prevention and treatment of diseases. These biological activities are mainly related to the presence of phenolic and terpenic compounds. This work reports a chemical profile analysis of extracts from leaves and calli of rosemary obtained by both pressurized liquid extraction and maceration. Chemical profiles were determined on calli extracts of 3, 6, 9, and 15 days of culture; chemical characterization and quantification of compounds was carried out using ultrahigh performance liquid chromatography-mass spectrometry. A total of 53 metabolites were identified in callus and 47 compounds in leaf extracts, of which 25 correspond to phenolic compounds, mainly flavonoids and flavones, 13 terpenes that include phenolic terpenes and one diterpenolactone, two glycosides which correspond to 6-O-caffeoyl-ß-D-fructofuranosil-(2→1)-α-D-glucopyranoside and primulaverin, an aromatic compound identified as fenantrenone and a growth regulator 12-hydroxy jasmonic acid. These results showed that undifferentiated rosemary cells accumulate the same compounds identified mainly in highly specialized tissues such as leaves. The plant cell culture supply the possibility of developing biotechnological processes to obtain compounds of commercial interest.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Extratos Vegetais/química , Folhas de Planta/química , Rosmarinus/química , Cinamatos/análise , Cinamatos/química , Depsídeos/análise , Depsídeos/química , Flavonoides/análise , Flavonoides/química , Glicosídeos/análise , Glicosídeos/química , Terpenos/análise , Terpenos/química , Ácido Rosmarínico
5.
Int J Mol Sci ; 20(20)2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31601020

RESUMO

Hyperpolarization-activated cationic HCN channels comprise four members (HCN1-4) that control dendritic integration, synaptic transmission and action potential firing. In the kidney, HCN1, HCN2 and HCN3 are differentially expressed and contribute to the transport of sodium, potassium (K+) and ammonium into the nephrons. HCN3 is regulated by K+ diets in the kidney. In this work we performed a proteomic analysis of HCN3 expressed in human embryonic kidney cells (HEK293 cells). More than 50% of the interacting proteins belonged to mitochondria. Therefore, we explored the presence of HCN channels in kidney mitochondria. By immunoblotting and immunogold electron microscopy HCN3 protein expression was found in rat kidney mitochondria; it was also confirmed in human kidney. Patch-clamp recordings of renal mitochondria and mitochondria from HEK293 cells overexpressing HCN1, HCN2 and HCN3 channels, stained with MitoTracker Green FM, indicated that only HCN3 could produce inwardly K+ currents that were inhibited by ZD7288, a specific blocker of HCN channels. Furthermore, ZD7288 caused inhibition of the oxygen consumption coupled to ATP synthesis and hyperpolarization of the inner mitochondrial membrane. In conclusion, we show for the first time that pacemaker HCN channels contribute to K+ transport in mitochondria facilitating the activity of the respiratory chain and ATP synthesis by controlling the inner mitochondrial membrane potential.


Assuntos
Rim/metabolismo , Mitocôndrias/metabolismo , Canais de Potássio/metabolismo , Potenciais de Ação , Respiração Celular , Cromatografia Líquida , Ativação do Canal Iônico , Mitocôndrias/genética , Nucleotídeos Cíclicos/metabolismo , Proteoma , Proteômica/métodos , Espectrometria de Massas em Tandem
6.
Rev Chil Pediatr ; 90(5): 522-532, 2019 Oct.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31859736

RESUMO

INTRODUCTION: The development of motor skills influences the capacity of the child to interact with the environment. Thus, several instruments have been created for their assessment. OBJECTIVE: To evaluate the internal consistency, reproducibility, and agreement level of age band 1 of the Movement Assessment Battery for Children - 2 in a preschool group. PATIENTS AND METHOD: Assessment study of diagnostic tests with 29 preschoolers, selected by convenience, enrollments in an educational ins titution in Bucaramanga city, Colombia. For the inter-evaluators reproducibility assessment, three evaluators watched each video independently. In the intra-evaluator reproducibility assessment, each evaluator watched the same video on two different occasions. The internal consistency, the intra- and inter-evaluator reproducibility, and the agreement level were determined using Cronbach's alpha co efficient, the Intraclass Correlation Coefficient (ICC), and the Bland and Altman limits of agreement method, respectively. RESULTS: Internal consistency of the total test for each of the three evaluators was higher than 0.60. Very good reliability was found for all items, domains, and total score of age band 1 of MABC-2 (ICC > 0.85), as well as good limits of agreement. CONCLUSIONS: age band 1 of MABC-2 Spanish version is an instrument with adequate reliability psychometric properties that can be used for the motor skills development evaluation in preschoolers.


Assuntos
Transtornos das Habilidades Motoras/diagnóstico , Destreza Motora/fisiologia , Criança , Pré-Escolar , Colômbia , Feminino , Humanos , Idioma , Masculino , Variações Dependentes do Observador , Psicometria , Reprodutibilidade dos Testes
7.
Glia ; 66(4): 828-845, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29288586

RESUMO

Microglia, the immune cells of the central nervous system, continuously survey the brain to detect alterations and maintain tissue homeostasis. The motility of microglial processes is indicative of their surveying capacity in normal and pathological conditions. The gold standard technique to study motility involves the use of two-photon microscopy to obtain time-lapse images from brain slices or the cortex of living animals. This technique generates four dimensionally-coded images which are analyzed manually using time-consuming, non-standardized protocols. Microglial process motility analysis is frequently performed using Z-stack projections with the consequent loss of three-dimensional (3D) information. To overcome these limitations, we developed ProMoIJ, a pack of ImageJ macros that perform automatic motility analysis of cellular processes in 3D. The main core of ProMoIJ is formed by two macros that assist the selection of processes, automatically reconstruct their 3D skeleton, and analyze their motility (process and tip velocity). Our results show that ProMoIJ presents several key advantages compared with conventional manual analysis: (1) reduces the time required for analysis, (2) is less sensitive to experimenter bias, and (3) is more robust to varying numbers of processes analyzed. In addition, we used ProMoIJ to demonstrate that commonly performed 2D analysis underestimates microglial process motility, to reveal that only cells adjacent to a laser injured area extend their processes toward the lesion site, and to demonstrate that systemic inflammation reduces microglial process motility. ProMoIJ is a novel, open-source, freely-available tool which standardizes and accelerates the time-consuming labor of 3D analysis of microglial process motility.


Assuntos
Imageamento Tridimensional/métodos , Microglia/citologia , Reconhecimento Automatizado de Padrão/métodos , Animais , Receptor 1 de Quimiocina CX3C/genética , Receptor 1 de Quimiocina CX3C/metabolismo , Lasers , Camundongos Transgênicos , Córtex Motor/citologia , Software , Córtex Somatossensorial/citologia , Córtex Somatossensorial/lesões , Córtex Somatossensorial/patologia
8.
Microb Ecol ; 75(4): 1049-1062, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29119317

RESUMO

Symbiotic bacteria can produce secondary metabolites and volatile compounds that contribute to amphibian skin defense. Some of these symbionts have been used as probiotics to treat or prevent the emerging disease chytridiomycosis. We examined 20 amphibian cutaneous bacteria for the production of prodigiosin or violacein, brightly colored defense compounds that pigment the bacteria and have characteristic spectroscopic properties making them readily detectable, and evaluated the antifungal activity of these compounds. We detected violacein from all six isolates of Janthinobacterium lividum on frogs from the USA, Switzerland, and on captive frogs originally from Panama. We detected prodigiosin from five isolates of Serratia plymuthica or S. marcescens, but not from four isolates of S. fonticola or S. liquefaciens. All J. lividum isolates produced violacein when visibly purple, while prodigiosin was only detected on visibly red Serratia isolates. When applied to cultures of chytrid fungi Batrachochytrium dendrobatidis (Bd) and B. salamandrivorans (Bsal), prodigiosin caused significant growth inhibition, with minimal inhibitory concentrations (MIC) of 10 and 50 µM, respectively. Violacein showed a MIC of 15 µM against both fungi and was slightly more active against Bsal than Bd at lower concentrations. Although neither violacein nor prodigiosin showed aerosol activity and is not considered a volatile organic compound (VOC), J. lividum and several Serratia isolates did produce antifungal VOCs. White Serratia isolates with undetectable prodigiosin levels could still inhibit Bd growth indicating additional antifungal compounds in their chemical arsenals. Similarly, J. lividum can produce antifungal compounds such as indole-3-carboxaldehyde in addition to violacein, and isolates are not always purple, or turn purple under certain growth conditions. When Serratia isolates were grown in the presence of cell-free supernatant (CFS) from the fungi, CFS from Bd inhibited growth of the prodigiosin-producing isolates, perhaps indicative of an evolutionary arms race; Bsal CFS did not inhibit bacterial growth. In contrast, growth of one J. lividum isolate was facilitated by CFS from both fungi. Isolates that grow and continue to produce antifungal compounds in the presence of pathogens may represent promising probiotics for amphibians infected or at risk of chytridiomycosis. In a global analysis, 89% of tested Serratia isolates and 82% of J. lividum isolates were capable of inhibiting Bd and these have been reported from anurans and caudates from five continents, indicating their widespread distribution and potential for host benefit.


Assuntos
Bactérias/metabolismo , Quitridiomicetos/efeitos dos fármacos , Indóis/antagonistas & inibidores , Indóis/metabolismo , Prodigiosina/antagonistas & inibidores , Prodigiosina/metabolismo , Compostos Orgânicos Voláteis/antagonistas & inibidores , Compostos Orgânicos Voláteis/metabolismo , Animais , Antifúngicos/farmacologia , Anuros/microbiologia , Bactérias/classificação , Bactérias/isolamento & purificação , Agentes de Controle Biológico/antagonistas & inibidores , Quitridiomicetos/crescimento & desenvolvimento , Quitridiomicetos/patogenicidade , Indóis/química , Testes de Sensibilidade Microbiana , Panamá , Filogenia , Prodigiosina/química , Serratia/classificação , Serratia/isolamento & purificação , Serratia/metabolismo , Pele/microbiologia , Suíça , Simbiose , Estados Unidos , Compostos Orgânicos Voláteis/química
9.
Rev Panam Salud Publica ; 41: e113, 2017.
Artigo em Espanhol | MEDLINE | ID: mdl-31391826

RESUMO

OBJECTIVE: The objectives of this study are to validate the construct of the stages of grief scale (FD-66) as an instrument for measuring the stages of grief and to evaluate its usefulness in discriminating among patients with chronic non-communicable diseases in terms of adherence to the pharmacological treatment prescribed. METHODS: A cross-sectional study was conducted from April to October 2015 to determine the association between the stages of grief and treatment adherence. Data were collected using a prolective design. Three instruments were applied: a sociodemographic document, the FD-66 scale, and the Morisky-Green questionnaire. Patients with a history of CNCDs were recruited from the Gustavo A. Madero Family Medicine Clinic in Mexico City. The data were analyzed using the appropriate statistical tests. RESULTS: A total of 165 patients were included. It was observed that high scores on the subscales of denial (odds ratio [OR]: 1.124; confidence interval of 95% [CI95%]: 1.066-1.186; P < 0,001); anger (OR: 1.157; CI95%: 1.080-1.240; P < 0.001), and depression (OR: 1.071; CI95%: 1.029-1.116; P = 0.001) are associated with poor treatment adherence; however, a high score on the acceptance subscale (OR: 0.913; CI95%: 0.880-0.948; P < 0.001) is associated with good treatment adherence. The greatest sensitivity among the subscales was observed in the denial and anger stages (area under the [ABC] curve: 0.597 in both). CONCLUSIONS: The FD-66 is an instrument with good construct validity as a tool for measuring the stages of grief and makes it possible to identify patients with CNCD that will adhere to treatment. We therefore recommend its use in outpatient medical consultations. Furthermore, our findings indicate that grief is a risk factor that increases poor treatment adherence.


OBJETIVO: Validar a construção da Escala facial de dor (EFD-66) como instrumento para medir as fases da dor e avaliar sua utilidade para discriminar, na consulta médica ambulatorial, os pacientes com doenças crônicas não transmissíveis (DCNT) que aderem ao tratamento medicamentoso. MÉTODOS: Estudo transversal para determinar a associação entre as fases da dor e o tratamento medicamentoso conduzido de abril a outubro de 2015. A coleta de dados foi realizada prospectivamente. Foram aplicados três instrumentos: uma ficha sociodemográfica, a escala EFD-66 e o teste de Morisky-Green. Foram recrutados pacientes com história de DCNT provenientes da Clínica de Medicina da Família "Gustavo A. Madero", na Cidade do México. Os dados foram analisados com os testes estatísticos apropriados. RESULTADOS: Foi estudada uma amostra de 165 pacientes. Observou-se que uma pontuação alta nas subescalas de negação (odds ratio [OR] 1,124; intervalo de confiança de 95% [IC95%] 1,066­1,186; P < 0,001), raiva (OR 1,157; IC95% 1,080­1,240; P < 0,001) e depressão (OR 1,071; IC95% 1,029­1,116; P = 0,001) está associada à não adesão ao tratamento medicamentoso. No entanto, uma pontuação alta na subescala de aceitação (OR 0,913; IC95% 0,880­0,948; P < 0,001) está associada à adesão ao tratamento medicamentoso. As subescalas com maior sensibilidade foram as fases de negação e raiva (área sob a curva [ASC]: 0,597 em ambas). CONCLUSÕES: A escala EFD-66 tem boa validade de construção como instrumento para medir as fases da dor e permite discriminar os pacientes com DCNT que aderem ao tratamento medicamentosos. Assim, recomendamos que esta escala seja aplicada em consultas médicas ambulatoriais. Além disso, nossos achados indicam que a dor é um fator de risco que contribui para a não adesão ao tratamento medicamentoso.

10.
Pflugers Arch ; 468(8): 1311-32, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27125215

RESUMO

Genetic deficiency of the SLC26A1 anion exchanger in mice is known to be associated with hyposulfatemia and hyperoxaluria with nephrolithiasis, but many aspects of human SLC26A1 function remain to be explored. We report here the functional characterization of human SLC26A1, a 4,4'-diisothiocyanato-2,2'-stilbenedisulfonic acid (DIDS)-sensitive, electroneutral sodium-independent anion exchanger transporting sulfate, oxalate, bicarbonate, thiosulfate, and (with divergent properties) chloride. Human SLC26A1-mediated anion exchange differs from that of its rodent orthologs in its stimulation by alkaline pHo and inhibition by acidic pHo but not pHi and in its failure to transport glyoxylate. SLC26A1-mediated transport of sulfate and oxalate is highly dependent on allosteric activation by extracellular chloride or non-substrate anions. Extracellular chloride stimulates apparent V max of human SLC26A1-mediated sulfate uptake by conferring a 2-log decrease in sensitivity to inhibition by extracellular protons, without changing transporter affinity for extracellular sulfate. In contrast to SLC26A1-mediated sulfate transport, SLC26A1-associated chloride transport is activated by acid pHo, shows reduced sensitivity to DIDS, and exhibits cation dependence of its DIDS-insensitive component. Human SLC26A1 resembles SLC26 paralogs in its inhibition by phorbol ester activation of protein kinase C (PKC), which differs in its undiminished polypeptide abundance at or near the oocyte surface. Mutation of SLC26A1 residues corresponding to candidate anion binding site-associated residues in avian SLC26A5/prestin altered anion transport in patterns resembling those of prestin. However, rare SLC26A1 polymorphic variants from a patient with renal Fanconi Syndrome and from a patient with nephrolithiasis/calcinosis exhibited no loss-of-function phenotypes consistent with disease pathogenesis.


Assuntos
Proteínas de Transporte de Ânions/metabolismo , Ânions/metabolismo , Cloretos/metabolismo , Animais , Proteínas de Transporte de Ânions/genética , Bicarbonatos/metabolismo , Transporte Biológico/fisiologia , Humanos , Concentração de Íons de Hidrogênio , Transporte de Íons/fisiologia , Mutação/genética , Oócitos/metabolismo , Oxalatos/metabolismo , Proteína Quinase C/metabolismo , Transportadores de Sulfato , Sulfatos/metabolismo , Tiossulfatos/metabolismo , Xenopus/metabolismo
11.
Histochem Cell Biol ; 145(1): 25-40, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26515056

RESUMO

Hyperpolarization-activated cationic and cyclic nucleotide-gated channels (HCN) comprise four homologous subunits (HCN1-HCN4). HCN channels are found in excitable and non-excitable tissues in mammals. We have previously shown that HCN2 may transport ammonium (NH4 (+)), besides sodium (Na(+)), in the rat distal nephron. In the present work, we identified HCN1 and HCN3 in the proximal tubule (PT) and HCN3 in the thick ascending limb of Henle (TALH) of the rat kidney. Immunoblot assays detected HCN1 (130 kDa) and HCN3 (90 KDa) and their truncated proteins C-terminal HCN1 (93 KDa) and N-terminal HCN3 (65 KDa) in enriched plasma membranes from cortex (CX) and outer medulla (OM), as well as in brush-border membrane vesicles. Immunofluorescence assays confirmed apical localization of HCN1 and HCN3 in the PT. HCN3 was also found at the basolateral membrane of TALH. We evaluated chronic changes in mineral dietary on HCN3 protein abundance. Animals were fed with three different diets: sodium-deficient (SD) diet, potassium-deficient (KD) diet, and high-potassium (HK) diet. Up-regulation of HCN3 was observed in OM by KD and in CX and OM by HK; the opposite effect occurred with the N-terminal truncated HCN3 in CX (KD) and OM (HK). SD diet did not produce any change. Since HCN channels activate with membrane hyperpolarization, our results suggest that HCN channels may play a role in the Na(+)-K(+)-ATPase activity, contributing to Na(+), K(+), and acid-base homeostasis in the rat kidney.


Assuntos
Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Túbulos Renais Proximais/metabolismo , Alça do Néfron/metabolismo , Canais de Potássio/metabolismo , Potássio na Dieta/metabolismo , Animais , Membrana Celular/metabolismo , Hipopotassemia/patologia , Córtex Renal/metabolismo , Medula Renal/metabolismo , Masculino , Microvilosidades/metabolismo , Técnicas de Patch-Clamp , Ratos , Ratos Wistar , Sódio/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo
12.
Nefrologia (Engl Ed) ; 43(4): 484-490, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37775346

RESUMO

Primary distal renal tubular acidosis (dRTA) is a rare tubulopathy characterised by the presence of hyperchloremic metabolic acidosis. It is caused by the existence of a defect in the function of the H+ -ATPase located on the luminal side of the α-intercalated cells or the Cl - HCO3- (AE1) anion exchanger located on the basolateral side. Patients do not acidify the urine after acid overload (NH4Cl) or after stimulating H+ secretion by obtaining a high intratubular concentration of an anion such as chlorine (pH is measured) or HCO3- (urinary pCO2 is measured). We present a family with autosomal dominant dRTA produced by a heterozygous mutation in the SLC4A1 gene in which the two paediatric members showed a test of normal maximum urinary pCO2. Our hypothesis is that since the H + -ATPase is intact, at least initially, the stimulation induced by intratubular electronegativity to secrete H + could be effective, which would allow the maximum urinary pCO2 to be paradoxically normal, which could explain the onset, moderate presentation of symptoms and late diagnosis in patients with this mutation. This is the first documented case of a dominant dRTA in Mexico.


Assuntos
Acidose Tubular Renal , Humanos , Criança , Acidose Tubular Renal/diagnóstico , Acidose Tubular Renal/genética , Proteína 1 de Troca de Ânion do Eritrócito/genética , Mutação , Ânions/metabolismo , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo
13.
J Neuroendocrinol ; 34(9): e13164, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35666232

RESUMO

Hypothalamic arginine vasopressin (AVP)-containing magnocellular neurosecretory neurons (AVPMNN) emit collaterals to synaptically innervate limbic regions influencing learning, motivational behaviour, and fear responses. Here, we characterize the dynamics of expression changes of two key determinants for synaptic strength, the postsynaptic density (PSD) proteins AMPAR subunit GluA1 and PSD scaffolding protein 95 (PSD95), in response to in vivo manipulations of AVPMNN neuronal activation state, or exposure to exogenous AVP ex vivo. Both long-term water deprivation in vivo, which powerfully upregulates AVPMNN metabolic activity, and exogenous AVP application ex vivo, in brain slices, significantly increased GluA1 and PSD95 expression as measured by western blotting, in brain regions reportedly receiving direct ascending innervations from AVPMNN (i.e., ventral hippocampus, amygdala and lateral habenula). By contrast, the visual cortex, a region not observed to receive AVPMNN projections, showed no such changes. Ex vivo application of V1a and V1b antagonists to ventral hippocampal slices ablated the AVP stimulated increase in postsynaptic protein expression measured by western blotting. Using a modified expansion microscopy technique, we were able to quantitatively assess the significant augmentation of PSD95 and GLUA1 densities in subcellular compartments in locus coeruleus tyrosine hydroxylase immunopositive fibres, adjacent to AVP axon terminals. Our data strongly suggest that the AVPMNN ascending system plays a role in the regulation of the excitability of targeted neuronal circuits through upregulation of key postsynaptic density proteins corresponding to excitatory synapses.


Assuntos
Sinapses , Tirosina 3-Mono-Oxigenase , Arginina Vasopressina/metabolismo , Hipocampo/metabolismo , Hipotálamo/metabolismo , Sinapses/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo
14.
Front Immunol ; 13: 1057499, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36389760

RESUMO

Polyhedrins are viral proteins present in a large family of baculoviruses that form occlusion bodies (polyhedra). These structures protect the virus particles from the outside environment until they are ingested by susceptible insects. Occluded viruses can sustain inclement weather for long periods of time. Therefore, the polyhedra is a natural preservative that keeps the viral structure intact at ambient temperature for years. In a previous study we identified the first 110 amino acids from polyhedrin (PH(1-110)) as a good candidate to carry antigens of interest. As a proof of concept, we produced a fusion protein with PH(1-110) and the green fluorescent protein (PH(1-110)GFP). The fusion protein associates spontaneously during its synthesis resulting in the formation of nanoparticles. Nasal immunization with these nanoparticles and in the absence of any adjuvant, results in a robust immune response with the production of IgG immunoglobulins that remained elevated for months and that selectively recognize the GFP but not PH(1-110). These results indicate that PH(1-110) is poorly immunogenic but capable of enhancing the immune response to GFP.


Assuntos
Nanopartículas , Vacinas , Temperatura , Antígenos , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo
15.
Kidney Int ; 80(8): 832-40, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21796099

RESUMO

Recent studies have identified Rhesus proteins as important molecules for ammonia transport in acid-secreting intercalated cells in the distal nephron. Here, we provide evidence for an additional molecule that can mediate NH3/NH4 excretion, the subtype 2 of the hyperpolarization-activated cyclic nucleotide-gated channel family (HCN2), in collecting ducts in rat renal cortex and medulla. Chronic metabolic acidosis in rats did not alter HCN2 protein expression but downregulated the relative abundance of HCN2 mRNA. Its cDNA was identical to the homolog from the brain and the protein was post-translationally modified by N-type glycosylation. Electrophysiological recordings in Xenopus oocytes injected with HCN2 cRNA found that potassium was transported better than ammonium, each of which was transported significantly better than sodium, criteria that are compatible with a role for HCN2 in ammonium transport. In microperfused rat outer medullary collecting duct segments, the initial rate of acidification, upon exposure to a basolateral ammonium chloride pulse, was higher in intercalated than in principal cells. A specific inhibitor of HCN2 (ZD7288) decreased acidification only in intercalated cells from control rats. In rats with chronic metabolic acidosis, the rate of acidification doubled in both intercalated and principal cells; however, ZD7288 had no significant inhibitory effect. Thus, HCN2 is a basolateral ammonium transport pathway of intercalated cells and may contribute to the renal regulation of body pH under basal conditions.


Assuntos
Canais Iônicos/fisiologia , Túbulos Renais Distais/metabolismo , Compostos de Amônio Quaternário/metabolismo , Acidose/metabolismo , Animais , Transporte Biológico , Imunofluorescência , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização , Canais Iônicos/análise , Túbulos Renais/metabolismo , Canais de Potássio , Ratos
16.
Rev Esp Salud Publica ; 952021 Mar 03.
Artigo em Espanhol | MEDLINE | ID: mdl-33654051

RESUMO

OBJECTIVE: In Spain, the number of persons that are in a surgery waiting list as well as the available surgery resources, differ across autonomous communities. The pandemic generated by COVID-19 has increased these waiting lists. In this study two objectives were pursued: on the one hand, to determine which are the resources that are determining the number of persons that are in a surgery waiting list per 1,000 inhabitants; on the other hand, to estimate the impact that the current pandemic has on the latter. METHODS: To estimate which are the resources that are having a greater impact on the waiting lists and to forecast the effect that the COVID-19 has on them, we use dynamic panel data models. The data on the surgery resources and on the waiting lists by autonomous communities is obtained from the Surveys on Health, Hospital Statistics and reports on waiting lists of the Ministry of Health, Consumption and Social Well Being and the Counsels. The sample period is 2012-2017 (last published year for surgery resources). In addition, a literature review is conducted and it shows the important and complexity of waiting list like a gestion tool of health system (Science, SciELO and Dialnet web data bases). RESULTS: COVID-19 will increase the waiting lists by approximately 7.6% to 19.14%, depending on the autonomous community. Not all the available surgery resources have the same relevance nor an equal effect on the reduction of the waiting lists. The most significant resources are the beds and operating rooms per 1,000 inhabitants. The hospital expenditure is not so relevant. CONCLUSIONS: The panel data models estimate the relation between the surgery resources and the waiting list. The latter is deemed complex and different across autonomous communities. In addition, these models allow to predict the expected increase in the waiting lists and are, thus, a useful instrument for their management.


OBJETIVO: En España, tanto el número de personas que están en espera de intervención quirúrgica, como los recursos quirúrgicos disponibles difieren entre comunidades autónomas. La pandemia ocasionada por la COVID-19 ha incrementado estas listas de espera. En este trabajo se persiguió un doble objetivo, por un lado, determinar cuáles son los recursos que tiene mayor influencia en el número de personas por mil habitantes que se encuentran en espera quirúrgica y, por otro, estimar el impacto que la pandemia actual ha generado. METODOS: Para estimar cuales son los recursos que más están repercutiendo en las listas de espera y predecir el efecto que la COVID-19 ejerce en ellas, utilizamos un modelo de datos de panel dinámico. Los datos de recursos quirúrgicos y listas de espera por comunidades autónomas se han obtenido de Encuestas de Salud, Estadísticas Hospitalarias e informes de listas de espera del Ministerio de Sanidad Consumo y Bienestar Social y de las Consejerías. El periodo muestral es 2012-2017 (último año publicado para recursos quirúrgicos). Además, se llevó a cabo una revisión de la literatura que permite corroborar la importancia y complejidad de las listas de espera como instrumento de gestión del sistema sanitario (bases de datos Web of Science, SciELO y Dialnet). RESULTADOS: La COVID-19 incrementará las listas de espera, aproximadamente entre el 7,6% y el 19,4%, dependiendo de la comunidad. No todos los recursos quirúrgicos disponibles tienen la misma importancia ni influyen de la misma manera en la reducción de las personas en espera. Los recursos más significativos son las camas y quirófanos por mil habitantes y no tanto el gasto en hospitales del Sistema Nacional de Salud. CONCLUSIONES: Los modelos de datos de panel permiten conocer la relación entre recursos quirúrgicos y lista de espera, la cual parece ser compleja y diferente entre comunidades. Además, estos modelos ayudan a predecir el incremento esperable y, por lo tanto, son un instrumento útil en la gestión de listas de espera.


Assuntos
COVID-19/epidemiologia , Cirurgia Geral/estatística & dados numéricos , Listas de Espera , Coleta de Dados , Número de Leitos em Hospital , Humanos , Internet , Salas Cirúrgicas , Espanha
17.
FEBS Open Bio ; 11(4): 1093-1108, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33565726

RESUMO

G protein-activated inward-rectifying potassium (K+ ) channels (Kir3/GIRK) participate in cell excitability. The GIRK5 channel is present in Xenopus laevis oocytes. In an attempt to investigate the physiological role of GIRK5, we identified a noncanonical di-arginine endoplasmic reticulum (ER) retention motif (KRXY). This retention motif is located at the N-terminal region of GIRK5, coded by two small exons found only in X. laevis and X. tropicalis. These novel exons are expressed through use of an alternative transcription start site. Mutations in the sequence KRXY produced functional channels and induced progesterone-independent oocyte meiotic progression. The chimeric proteins enhanced green fluorescent protein (EGFP)-GIRK5-WT and the EGFP-GIRK5K13AR14A double mutant, were localized to the ER and the plasma membrane of the vegetal pole of the oocyte, respectively. Silencing of GIRK5 or blocking of this channel by external barium prevented progesterone-induced meiotic progression. The endogenous level of GIRK5 protein decreased through oocyte stages in prophase I augmenting by progesterone. In conclusion, we have identified a unique mechanism by which the expression pattern of a K+ channel evolved to control Xenopus oocyte maturation.


Assuntos
Motivos de Aminoácidos , Sequência de Aminoácidos , Retículo Endoplasmático/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/química , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/metabolismo , Oócitos/metabolismo , Domínios e Motivos de Interação entre Proteínas , Proteínas de Xenopus/química , Proteínas de Xenopus/metabolismo , Animais , Sequência Conservada , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/genética , Humanos , Oócitos/efeitos dos fármacos , Filogenia , Ligação Proteica , Proteínas de Xenopus/genética , Xenopus laevis
18.
Children (Basel) ; 8(5)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34067968

RESUMO

Childhood and adolescence represent critical periods where beverage and food consumption behaviors are learned and developed. Mexican mothers' presence and influence are instrumental in shaping such behaviors. The aim of this study was to estimate the prevalence and risk associations of maternal factors for unhealthy patterns of beverage intake. This study analyzed data from a population-based cross-sectional study of healthy children and adolescents from Mexico City. Data of subject's total water intake (TWI) and its' sources were collected using two 24-h recall surveys. Patterns of beverage intake were constructed based on the guidance system of beverage consumption in the US. Maternal factors of interest included age, body mass index (BMI), mother's educational level (MEL), socioeconomic status (SES), and belongingness to the paid workforce (BPW). Data of 1532 subject-mother dyads informed that 47% of subjects did not meet the Institute of Medicine (IOM) recommendations for TWI, and 94.6% showed an unhealthy beverage intake pattern, mainly consisting in a lower intake of water and a higher intake of caloric beverages with some nutrients; and calorically sweetened beverages. The major sources of hydration were caloric beverages with some nutrients (i.e., whole milk, fruit water, and flavored milk). The highest risk association for an unhealthy beverage intake pattern was seen in those subjects with mothers in the cluster with lower SES, lower MEL, lower proportion of BPW, higher BMI, and younger age (OR = 9.3, 95% CI 1.2-72.8, P = 0.03). Thus, there is a remarkably high prevalence of an unhealthy pattern of beverage intake, and specific maternal factors may be implicated as enablers of such behaviors, which is also addressable for future interventions.

19.
Am J Physiol Renal Physiol ; 299(1): F255-64, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20427469

RESUMO

The fine regulation of Na(+) and K(+) transport takes place in the cortical distal nephron. It is well established that K(+) secretion occurs through apical K(+) channels: the ROMK and the Ca(2+)- and voltage-dependent maxi-K. Previously, we identified the voltage-gated Kv1.3 channel in the inner medulla of the rat kidney (Escobar LI, Martínez-Téllez JC, Salas M, Castilla SA, Carrisoza R, Tapia D, Vázquez M, Bargas J, Bolívar JJ. Am J Physiol Cell Physiol 286: C965-C974, 2004). To examine the role of Kv1.3 in the renal regulation of K(+) homeostasis, we characterized the effect of dietary K(+) on the molecular and functional expression of this channel. We performed real-time-PCR and immunoblot assays in kidneys from rats fed a control (CK; 1.2% wt/wt) or high-K(+) (HK; 10% wt/wt) diet for 5-15 days. Kv1.3 mRNA and protein expression did not change with HK in the whole kidney. However, dietary K(+) loading provoked a change in the cellular distribution of Kv1.3 from the cytoplasm to apical membranes. Immunolocalization of Kv1.3 detected the channel exclusively in the intercalated cells. We investigated whether Kv1.3 mediated K(+) transport in microperfused cortical collecting ducts (CCDs). The HK diet led to an increase in net K(+) transport from 7.4 +/- 1.1 (CK) to 11.4 +/- 1.0 (HK) pmol x min(-1.) mm(-1). Luminal margatoxin, a specific blocker of Kv1.3, decreased net K(+) secretion in HK CCDs to 6.0 +/- 1.6 pmol x min(-1.) mm(-1). Our data provide the first evidence that Kv1.3 channels participate in K(+) secretion and that apical membrane localization of Kv1.3 is enhanced in the intercalated cells by dietary K(+) loading.


Assuntos
Ativação do Canal Iônico , Rim/metabolismo , Canal de Potássio Kv1.3/metabolismo , Potássio na Dieta/metabolismo , Animais , Western Blotting , Homeostase , Concentração de Íons de Hidrogênio , Imuno-Histoquímica , Rim/citologia , Rim/efeitos dos fármacos , Cinética , Canal de Potássio Kv1.3/antagonistas & inibidores , Canal de Potássio Kv1.3/genética , Masculino , Potenciais da Membrana , Microscopia de Fluorescência , Perfusão , Bloqueadores dos Canais de Potássio/farmacologia , Potássio na Dieta/urina , Transporte Proteico , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Venenos de Escorpião/farmacologia , Fatores de Tempo , Urinálise
20.
Histochem Cell Biol ; 133(2): 189-99, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19921238

RESUMO

Potassium (K(+)) channels participate in K(+) secretion, K(+) recycling, and cell volume regulation and help to maintain the resting potential in mammalian kidneys. Previously, we identified a set of voltage-gated K(+) channels (Kv1) in the inner medullary collecting duct of the rat kidney. In the present work, we identified the voltage-gated K(+) channel ether-à-go-go-related gene (ERG) in the rat kidney. mRNAs of ERG1a and its N-terminal splice-variant ERG1b were detected. Immunoblots of the cortex and medulla revealed two molecular mass proteins of 135 and 80 kDa, consistent in size with the nonglycosylated ERG1a and ERG1b isoforms, respectively. However, bands of 155 and 95 kDa, corresponding to mature glycosylated ERG1a and ERG1b, respectively, were also observed. In our immunohistochemical experiments, we could not differentiate the ERG1 isoforms because we used an antibody against a carboxy-terminal epitope. ERG1 was differentially localized in specific nephron segments: its localization was intracellular in the proximal tubule and medullary collecting ducts and in the apical membranes in the distal convoluted and connecting tubules. ERG1 was also abundant in glomerular arterioles and renal vessels. In summary, ERG1 displays a heterogeneous distribution in the rat kidney.


Assuntos
Canais de Potássio Éter-A-Go-Go/biossíntese , Rim/ultraestrutura , Animais , Canal de Potássio ERG1 , Imunofluorescência , Rim/citologia , Masculino , Ratos , Ratos Wistar
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