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1.
Br J Pharmacol ; 181(16): 2905-2922, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38679932

RESUMO

BACKGROUND AND PURPOSE: ATP is highly accumulated in secretory vesicles and secreted upon exocytosis from neurons and endocrine cells. In adrenal chromaffin granules, intraluminal ATP reaches concentrations over 100 mM. However, how these large amounts of ATP contribute to exocytosis has not been investigated. EXPERIMENTAL APPROACH: Exocytotic events in bovine and mouse adrenal chromaffin cells were measured with single cell amperometry. Cytosolic Ca2+ measurements were carried out in Fluo-4 loaded cells. Submembrane Ca2+ was examined in PC12 cells transfected with a membrane-tethered Ca2+ indicator Lck-GCaMP3. ATP release was measured using the luciferin/luciferase assay. Knockdown of P2X7 receptors was induced with short interfering RNA (siRNA). Direct Ca2+ influx through this receptor was measured using a P2X7 receptor-GCamp6 construct. KEY RESULTS: ATP induced exocytosis in chromaffin cells, whereas the ectonucleotidase apyrase reduced the release events induced by the nicotinic agonist dimethylphenylpiperazinium (DMPP), high KCl, or ionomycin. The purinergic agonist BzATP also promoted a secretory response that was dependent on extracellular Ca2+. A740003, a P2X7 receptor antagonist, abolished secretory responses of these secretagogues. Exocytosis was also diminished in chromaffin cells when P2X7 receptors were silenced using siRNAs and in cells of P2X7 receptor knockout mice. In PC12 cells, DMPP induced ATP release, triggering Ca2+ influx through P2X7 receptors. Furthermore, BzATP, DMPP, and KCl allowed the formation of submembrane Ca2+ microdomains inhibited by A740003. CONCLUSION AND IMPLICATIONS: Autocrine activation of P2X7 receptors constitutes a crucial feedback system that amplifies the secretion of catecholamines in chromaffin cells by favouring submembrane Ca2+ microdomains.


Assuntos
Trifosfato de Adenosina , Catecolaminas , Células Cromafins , Exocitose , Receptores Purinérgicos P2X7 , Animais , Receptores Purinérgicos P2X7/metabolismo , Células Cromafins/metabolismo , Células Cromafins/efeitos dos fármacos , Bovinos , Trifosfato de Adenosina/metabolismo , Camundongos , Catecolaminas/metabolismo , Exocitose/efeitos dos fármacos , Células PC12 , Ratos , Cálcio/metabolismo , Comunicação Autócrina , Camundongos Endogâmicos C57BL , Células Cultivadas , Masculino
2.
BMC Public Health ; 24(1): 990, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594646

RESUMO

BACKGROUND: Despite multiple recommendations and strategies implemented at a national and international level, cigarette smoking, alcohol consumption, and cannabis use during pregnancy remains high in most countries. The objective of this study was to examine key stakeholders' perception of the treatment interventions adopted in Spain, to identify political, organizational and personal factors associated with successful implementation, and to propose strategies for improvement. METHODS: A qualitative study with a phenomenological approach was conducted in 2022. The target groups were: (1) clinical decision makers in the field of addiction science, (2) health professionals who carry out treatment interventions, and (3) pregnant individuals who use tobacco, alcohol or cannabis. Two focus groups and eight in-depth interviews were conducted, recorded, and transcribed. Exploratory analysis and inductive open coding was performed, codes were merged into categories, and subcategories were identified. RESULTS: The analysis resulted in 10 subcategories which were further merged into three main categories: (1) Degree of adoption and utility of treatment interventions implemented; (2) Needs and demands with respect to the organization of treatment interventions; and, (3) Personal barriers to and facilitators for treatment. Respondents reported that despite multiple national and regional cessation initiatives, treatment interventions were rarely adopted in clinical practice. Health care administrators demanded reliable records to quantify substance use for better planning of activities. Health care professionals advocated for additional time and training and both echoed the importance of integrating cessation interventions into routine prenatal care and creating in-house specialized units. The difficulty in quitting, lack of awareness of risk for foetus and child and the controversial advice were identified as barriers by pregnant individuals. CONCLUSIONS: Consistent with previous work, this study found that cessation strategies implemented by the health authorities are not effective if they are not accompanied by organizational and behavioral changes. The current study identifies a set of factors that could be pivotal in ensuring the success of treatment interventions targeting tobacco, alcohol and cannabis use among pregnant individuals.


Assuntos
Abandono do Hábito de Fumar , Feminino , Humanos , Gravidez , Tomada de Decisões , Etanol , Percepção , Cuidado Pré-Natal , Pesquisa Qualitativa , Abandono do Hábito de Fumar/métodos
3.
Sci Rep ; 14(1): 6791, 2024 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-38514697

RESUMO

Extracellular vesicles (EVs) released from cells attract interest for their possible role in health and diseases. The detection and characterization of EVs is challenging due to the lack of specialized methodologies. Raman spectroscopy, however, has been suggested as a novel approach for biochemical analysis of EVs. To extract information from the spectra, a novel deep learning architecture is explored as a versatile variant of autoencoders. The proposed architecture considers the frequency range separately from the intensity of the spectra. This enables the model to adapt to the frequency range, rather than requiring that all spectra be pre-processed to the same frequency range as it was trained on. It is demonstrated that the proposed architecture accepts Raman spectra of EVs and lipoproteins from 13 biological sources and from two laboratories. High reconstruction accuracy is maintained despite large variances in frequency range and noise level. It is also shown that the architecture is able to cluster the biological nanoparticles by their Raman spectra and differentiate them by their origin without pre-processing of the spectra or supervision during learning. The model performs label-free differentiation, including separating EVs from activated vs. non-activated blood platelets and EVs/lipoproteins from prostate cancer patients versus non-cancer controls. The differentiation is evaluated by creating a neural network classifier that observes the features extracted by the model to classify the spectra according to their sample origin. The classification reveals a test sensitivity of 92.2 % and selectivity of 92.3 % over 769 measurements from two labs that have different measurement configurations.


Assuntos
Vesículas Extracelulares , Nanopartículas , Neoplasias da Próstata , Masculino , Humanos , Vesículas Extracelulares/química , Neoplasias da Próstata/diagnóstico , Lipoproteínas , Aprendizado de Máquina Supervisionado , Análise Espectral Raman/métodos
4.
Toxicon ; 241: 107665, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38428752

RESUMO

The pods of Neltuma spp. have shown potential as a source of protein and energy in livestock. However, prolonged consumption of some of these species can lead to neurological symptoms in ruminants. This study aimed to determine the alkaloid content, as well as the in vitro and in vivo effects of an alkaloid-enriched extract (AEE) from N. alpataco pods. High performance liquid chromatography-high resolution mass spectrometry (HPLC-HRMS) identified juliprosine and juliprosopine as primary alkaloids, with juliprosine being most abundant. AEE from N. alpataco demonstrated dose-dependent cytotoxicity on glioma cells after 48 h, with a 50% cytotoxic concentration (CC50) of 24.69 µg/mL. However, the release of LDH was observed only at the highest tested concentration, indicating cellular damage. Further examination through phase-contrast microscopy and dual acridine orange/ethidium bromide fluorescence staining revealed morphological changes consistent with an apoptotic mechanism of cell death, ultimately leading to secondary necrosis. Finally, the LD50 after intraperitoneal injection in mice was determined to be 12.98 mg/kg. Taken together, these findings demonstrated for the first time the in vivo and in vitro toxicity of the AEE from N. alpataco pods.


Assuntos
Alcaloides , Antineoplásicos , Prosopis , Camundongos , Animais , Alcaloides/química , Extratos Vegetais/farmacologia , Antineoplásicos/farmacologia , Apoptose
5.
J Extracell Vesicles ; 12(11): e12376, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37942918

RESUMO

Extracellular vesicles (EVs) in blood plasma are recognized as potential biomarkers for disease. Although blood plasma is easily obtainable, analysis of EVs at the single particle level is still challenging due to the biological complexity of this body fluid. Besides EVs, plasma contains different types of lipoproteins particles (LPPs), that outnumber EVs by orders of magnitude and which partially overlap in biophysical properties such as size, density and molecular makeup. Consequently, during EV isolation LPPs are often co-isolated. Furthermore, physical EV-LPP complexes have been observed in purified EV preparations. Since co-isolation or association of LPPs can impact EV-based analysis and biomarker profiling, we investigated the presence and formation of EV-LPP complexes in biological samples by using label-free atomic force microscopy, cryo-electron tomography and synchronous Rayleigh and Raman scattering analysis of optically trapped particles and fluorescence-based high sensitivity single particle flow cytometry. Furthermore, we evaluated the impact on flow cytometric analysis in the presence of LPPs using in vitro spike-in experiments of purified tumour cell line-derived EVs in different classes of purified human LPPs. Based on orthogonal single-particle analysis techniques we demonstrate that EV-LPP complexes can form under physiological conditions. Furthermore, we show that in fluorescence-based flow cytometric EV analysis staining of LPPs, as well as EV-LPP associations, can influence quantitative and qualitative EV analysis. Lastly, we demonstrate that the colloidal matrix of the biofluid in which EVs reside impacts their buoyant density, size and/or refractive index (RI), which may have consequences for down-stream EV analysis and EV biomarker profiling.


Assuntos
Vesículas Extracelulares , Humanos , Vesículas Extracelulares/fisiologia , Imagem Individual de Molécula , Biomarcadores , Linhagem Celular Tumoral , Lipoproteínas LDL
6.
Aten Primaria ; 55(11): 102732, 2023 Aug 11.
Artigo em Espanhol | MEDLINE | ID: mdl-37573833

RESUMO

OBJECTIVE: To explore the opinion of different key stakeholders regarding the requirements that tobacco, alcohol and/or cannabis cessation interventions should meet to be implemented and to be acceptable and useful during pregnancy. DESIGN: A qualitative study with phenomenological approach. SITE: The study was conducted in Spain in 2022. PARTICIPANTS: Decision makers, health professionals, pregnant women using tobacco, alcohol and/or cannabis and their partners who are also users. METHODS: Data were collected through focus groups and in-depth interviews, until discourse saturation was reached and accurately transcribed. Exploratory analysis and inductive open coding were conducted, codes were merged into categories and subcategories were identified. RESULTS: Four categories and 18 subcategories were identified. The results suggest that interventions should be multicomponent. Among the interventions most accepted by pregnant women and their partners were specific cessation consultations, information, peer support (although they did not specify how) and financial incentives. Among other options to consider, co-oximetry, proposed by managers to obtain an objective register. CONCLUSIONS: The conclusion is that this intervention should be carried out at the level of prenatal care in primary care. There are doubts regarding the frequency, purpose, and follow-up of this multicomponent intervention, as well as the possibility of incorporating couples.

7.
J Endourol ; 37(8): 935-939, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37337653

RESUMO

Purpose: On February 6, 2018, the European Atomic Energy Community reduced the annual equivalent dose limit for the lens from 150 to 20 mSv/year, because of its association with cataracts at low radiation doses. Our aim was to estimate the radiation doses received by the lens during endourologic procedures that require fluoroscopy. Materials and Methods: Multicenter study including prospective data of annual eye dosimeters between 2017 and 2020. Four endourologists used an eye dosimeter in endourologic procedures that require fluoroscopy (ureteroscopy, retrograde intrarenal surgery, and percutaneous nephrolithotomy). Surgeons 1 and 2 wore leaded glasses; surgeon 1 also used the as low as reasonably achievable (ALARA) protocol. Descriptive statistical analysis using SPSS 25.0 was conducted. Results: Surgeons 1, 2, 3, and 4 performed a median of 159, 586, 102, and 129 endourologic procedures per year, respectively, for a total of 641, 2340, 413, and 350 procedures between 2017 and 2020. The median annual dose of lens radiation exposure was 0.16, 1.18, 3.79, and 1.42 mSv per year, respectively, which corresponds to 0.001, 0.009, 0.024, and 0.012 mSv per procedure. The two surgeons who used leaded glasses registered a lower radiation dose per procedure (0.001 vs 0.027). Similarly, the urologist who used the ALARA protocol registered the lowest lens radiation dose compared with the three surgeons who did not use it (0.001 vs 0.023). Conclusions: The endourologists who participated in this study effectively comply with current guidelines on radiation exposure to the lens. Registered eye lens radiation does not seem to be related to the number of procedures but rather to the use of leaded glasses and the ALARA protocol.


Assuntos
Cristalino , Exposição Ocupacional , Exposição à Radiação , Humanos , Estudos Prospectivos , Doses de Radiação , Fluoroscopia/efeitos adversos , Estudos Multicêntricos como Assunto
8.
Rev Esp Enferm Dig ; 115(5): 223-224, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37114390

RESUMO

Gastrointestinal (GI) Endoscopy is a basic competence for the management of gastrointestinal diseases. However, it should not be regarded as an independent training technique. Rather it is a part of a continuous and accredited process that requires clinical knowledge from the gastroenterologist to keep skills up-to-date in a constantly evolving medical subspecialty. Thus, the only official accredited way for training in GI endoscopy is through the Specialized Health Training program in the Management of the Digestive Diseases administered by the Spanish Ministry of Health.


Assuntos
Gastroenterologistas , Gastroenteropatias , Humanos , Endoscopia Gastrointestinal/métodos , Currículo , Gastroenteropatias/diagnóstico por imagem , Gastroenteropatias/terapia , Competência Clínica
9.
Med Clin (Barc) ; 160(6): 237-244, 2023 03 24.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-36049977

RESUMO

INTRODUCTION: The goal of this study was to estimate and to describe the smoking cessation changes in Spain from 1987 to 2020, according to the main sociodemographic characteristics. MATERIAL AND METHOD: Analysis of the historical series of the Spanish National Health Survey and the European Health Survey in Spain. Quit rate (QR) was defined as the number of former smokers among the total number of people who are smokers or have smoked at some time in their life. Other included variables were year of survey, age, gender and educational level. Poisson regression models were simultaneously adjusted for sociodemographic characteristics, estimating QR and its 95% confidence intervals (CIs) for each year. RESULTS: The absolute difference in standardized QR increased from 1987 to 2017 by 18.6% (95%CI: 16.8-20.4), being moderately higher in men (19.2%; 95%CI: 17.1-21.4) than in women (16.5%; 95%CI: 13.3-19.7). An increase in QR was observed in all age groups, but its magnitude increased with age, estimating a difference in QR between 1987 and 2017 of 22.4% (95%CI: 17.7-27.1) in those aged over 64. People having university studies showed a higher QR during the period, 32.7% (95%CI: 27.5-38.0), especially when compared to those with a lower level of education (9.0%; 95%CI: 4.8-13.2). CONCLUSION: QR has increased sharply and steadily since 1987, however important differences were detected according to age and educational level, highlighting the large increase in inequity observed in these 33years of evolution.


Assuntos
Abandono do Hábito de Fumar , Masculino , Humanos , Feminino , Idoso , Fumar , Espanha , Inquéritos Epidemiológicos , Inquéritos e Questionários
10.
Front Oncol ; 12: 887210, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35686092

RESUMO

Virtually every cell in the body releases extracellular vesicles (EVs), the contents of which can provide a "fingerprint" of their cellular origin. EVs are present in all bodily fluids and can be obtained using minimally invasive techniques. Thus, EVs can provide a promising source of diagnostic, prognostic, and predictive biomarkers, particularly in the context of cancer. Despite advances using EVs as biomarkers in adult cancers, little is known regarding their use in pediatric cancers. In this review, we provide an overview of published clinical and in vitro studies in order to assess the potential of using EV-derived biomarkers in pediatric solid tumors. We performed a systematic literature search, which yielded studies regarding desmoplastic small round cell tumor, hepatoblastoma, neuroblastoma, osteosarcoma, and rhabdomyosarcoma. We then determined the extent to which the in vivo findings are supported by in vitro data, and vice versa. We also critically evaluated the clinical studies using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) system, and we evaluated the purification and characterization of EVs in both the in vivo and in vitro studies in accordance with MISEV guidelines, yielding EV-TRACK and PedEV scores. We found that several studies identified similar miRNAs in overlapping and distinct tumor entities, indicating the potential for EV-derived biomarkers. However, most studies regarding EV-based biomarkers in pediatric solid tumors lack a standardized system of reporting their EV purification and characterization methods, as well as validation in an independent cohort, which are needed in order to bring EV-based biomarkers to the clinic.

11.
Rev Esp Enferm Dig ; 114(2): 70-72, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35045718

RESUMO

The performance of an endoscopic procedure involves introducing an endoscope through the mouth or the anus, which may potentially lead to lethal infection. The risk increases when complex and difficult-to-clean scopes are used, as in the case of duodenoscopes. Side-viewing duodenoscopes are complex in design, with the camera and working channel exit located on one side of the endoscope's distal end, and with an elevator nail also located at this point for catheter redirection. This complex design may facilitate the presence of blind areas not easy to access for cleaning, resulting in suboptimal disinfection of the duodenoscope and therefore a higher risk of bacterial infection. This is of particular importance in particularly vulnerable patients like those who are immunosuppressed (e.g., transplanted patients) or have a malignant disease and are receiving chemotherapy. Moreover, in the era of ¨superbugs¨, like carbapenem-resistant Enterobacteriaceae, infection outbreaks related to endoscopic retrograde cholangiopancreatography (ERCP) have been reported with a significant mortality rate.


Assuntos
Desinfecção , Duodenoscópios , Colangiopancreatografia Retrógrada Endoscópica , Custos e Análise de Custo , Atenção à Saúde , Duodenoscópios/microbiologia , Humanos
12.
Gastroenterol Hepatol ; 45(2): 106-113, 2022 Feb.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-34023478

RESUMO

INTRODUCTION: Colorectal cancer 5-years-survival is 57%, partway due to a low rate of participation in screening programmes. Instruments analyzing causes of low adherence are needed. OBJECTIVE: To evaluate the validity and internal consistency of the Spanish version of Rawl's Questionnaire for the screening of colorectal cancer by faecal occult blood testing. TYPE OF STUDY: Questionnaire validation methodology. LOCATION: Three Primary Care Centres in Valencia. VARIABLES: Age, sex, civil status, educational level, social class, smoking, alcohol consumption, body mass index, personal and family history of cancer. RESULTS: We analyzed 408 individuals (237 cases and 171 controls). Mean age was 59.45 years (SD 5.17). Internal consistency of all variables reached a Cronbach's alfa of 0.796. The Cronbach's alfa benefit dimension of the screening was 0.871 and for the barrier dimension of the screening it was 0.817. Intraclass correlation coefficients of the test-retest for the benefit dimension of the screening was 0.809 (CI 95% 0.606-0.913) and 0.499 (CI 95% 0.126-0.750) for the barrier dimension. CONCLUSION: The Spanish version of Rawl's Questionnaire is valid, reliable and reproducible, so we have this validated instrument with which to identify barriers and benefits in a colorectal screening programme in Spain.


Assuntos
Neoplasias Colorretais/diagnóstico , Idioma , Sangue Oculto , Traduções , Fatores Etários , Idoso , Estudos de Casos e Controles , Escolaridade , Humanos , Pessoa de Meia-Idade , Fatores Sexuais
13.
Rev Esp Enferm Dig ; 114(4): 219-225, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-33733806

RESUMO

INTRODUCTION: despite advances in imaging diagnostic modalities, hepatocellular carcinoma is sometimes incidentally diagnosed on histological examination of the liver explant. The objectives of the study were: a) to compare the characteristics between incidental and known hepatocellular carcinoma; and b) to estimate survival and tumor recurrence after liver transplantation. MATERIAL AND METHODS: a retrospective, single-center study was performed. The inclusion criteria were: a) cirrhotic patients, age ≥ 18 years; b) liver transplantation between 1998 and 2018; and c) hepatocellular carcinoma diagnosed via histopathologic examination of the explanted liver. Cholangiocarcinoma and patients with early retransplantation were excluded. Multivariate analysis was performed using binomial logistic regression to assess the factors associated with incidental hepatocellular carcinoma. Kaplan-Meier curves were plotted to explore the impact on overall survival and recurrence free survival. RESULTS: two hundred and sixty-nine patients were enrolled. The prevalence of incidental hepatocellular carcinoma was 4.18 % (95 % CI: 2.89-6.01 %) of all liver transplants performed in cirrhotic patients. The median diameter of the main nodule was smaller in incidental hepatocellular carcinoma (20 vs 27 mm, p = 0.004), although they were more likely to be beyond the Up-to-Seven criteria on explant examination (22.2 % vs 7.5 %, p = 0.001), with no differences in any other histological features. No differences were found in overall survival rates (incidental 70.2 % vs 70.4 %, p = 0.87) or recurrence-free survival (incidental 100 % vs 83.8 %, p = 0.07) at five years. CONCLUSION: incidental hepatocellular carcinoma are smaller in size and are more frequently found to be beyond the Up-to-Seven criteria. However, no differences were found in overall survival rates or recurrence-free survival, although there was no tumor recurrence in the incidental hepatocellular carcinoma group.


Assuntos
Neoplasias dos Ductos Biliares , Carcinoma Hepatocelular , Neoplasias Hepáticas , Transplante de Fígado , Adolescente , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/cirurgia , Estudos de Coortes , Humanos , Estimativa de Kaplan-Meier , Cirrose Hepática/patologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/cirurgia , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/patologia , Estudos Retrospectivos , Resultado do Tratamento
14.
Rev Esp Enferm Dig ; 113(12): 849, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34470448

RESUMO

Chronic intestinal pseudo-obstruction (CIPO) is characterized by symptoms and signs of bowel obstruction in the absence of an anatomical cause. Almost 50 % of cases are secondary to systemic diseases of neurological, paraneoplastic, autoimmune, metabolic, or infectious origin.


Assuntos
Condrossarcoma , Pseudo-Obstrução Intestinal , Condrossarcoma/complicações , Doença Crônica , Humanos , Pseudo-Obstrução Intestinal/diagnóstico por imagem , Pseudo-Obstrução Intestinal/etiologia , Neoplasias de Tecido Conjuntivo e de Tecidos Moles
15.
Proc Natl Acad Sci U S A ; 118(32)2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34301850

RESUMO

Pannexin1 (Panx1) channels are ubiquitously expressed in vertebrate cells and are widely accepted as adenosine triphosphate (ATP)-releasing membrane channels. Activation of Panx1 has been associated with phosphorylation in a specific tyrosine residue or cleavage of its C-terminal domains. In the present work, we identified a residue (S394) as a putative phosphorylation site by Ca2+/calmodulin-dependent kinase II (CaMKII). In HeLa cells transfected with rat Panx1 (rPanx1), membrane stretch (MS)-induced activation-measured by changes in DAPI uptake rate-was drastically reduced by either knockdown of Piezo1 or pharmacological inhibition of calmodulin or CaMKII. By site-directed mutagenesis we generated rPanx1S394A-EGFP (enhanced green fluorescent protein), which lost its sensitivity to MS, and rPanx1S394D-EGFP, mimicking phosphorylation, which shows high DAPI uptake rate without MS stimulation or cleavage of the C terminus. Using whole-cell patch-clamp and outside-out excised patch configurations, we found that rPanx1-EGFP and rPanx1S394D-EGFP channels showed current at all voltages between ±100 mV, similar single channel currents with outward rectification, and unitary conductance (∼30 to 70 pS). However, using cell-attached configuration we found that rPanx1S394D-EGFP channels show increased spontaneous unitary events independent of MS stimulation. In silico studies revealed that phosphorylation of S394 caused conformational changes in the selectivity filter and increased the average volume of lateral tunnels, allowing ATP to be released via these conduits and DAPI uptake directly from the channel mouth to the cytoplasmic space. These results could explain one possible mechanism for activation of rPanx1 upon increase in cytoplasmic Ca2+ signal elicited by diverse physiological conditions in which the C-terminal domain is not cleaved.


Assuntos
Sinalização do Cálcio , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Conexinas/química , Conexinas/metabolismo , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/metabolismo , Cálcio/metabolismo , Calmodulina/metabolismo , Membrana Celular/química , Membrana Celular/metabolismo , Conexinas/genética , Citoplasma/metabolismo , Proteínas de Fluorescência Verde/genética , Células HeLa , Humanos , Indóis/farmacocinética , Canais Iônicos/genética , Canais Iônicos/metabolismo , Simulação de Dinâmica Molecular , Proteínas do Tecido Nervoso/genética , Técnicas de Patch-Clamp , Fosforilação , Serina/genética , Serina/metabolismo
16.
J Vet Diagn Invest ; 33(5): 1018-1022, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34160311

RESUMO

We investigated 2 outbreaks of osteomalacia as a result of phosphorus (P) deficiency in herds of lactating beef cows grazing subtropical native pastures in Uruguay. Cows exhibited pica, difficulty to stand and walk, rib fractures, and body weight loss even with adequate forage availability. Osteopenia and severe osteomalacia were observed on gross and histologic examination. The concentrations of bicarbonate-extractable P in soil (4.0, 4.1 mg P/kg), total P in pasture (0.9, 1.1 g P/kg), inorganic P in serum (1.0, 0.71 mmol P/L), and P in bone (73 mg P/mL) were all low. Although injectable and mineral salt supplements provided additional P in both outbreaks, these supplementary amounts were insufficient to prevent P deficiency. The P ingested by the cows from the pasture and supplements would have provided 20-55% of their daily P requirements of ~21 g P/d. Osteomalacia occurred in cattle at the 2 ranches as a result of severe P deficiency in the soil and forage, and inadequate P supplementation. Following diagnosis, control of P deficiency in beef cattle requires estimation of the amount of pasture P ingested and provision of sufficient additional supplementary P to meet the animals' requirements.


Assuntos
Doenças dos Bovinos , Osteomalacia , Fósforo , Ração Animal/análise , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Suplementos Nutricionais , Feminino , Lactação , Osteomalacia/induzido quimicamente , Osteomalacia/veterinária , Fósforo/análise , Fósforo/deficiência , Uruguai/epidemiologia
17.
Int J Mol Sci ; 22(3)2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33499026

RESUMO

Wound healing is a dynamic process required to maintain skin integrity and which relies on the precise migration of different cell types. A key molecule that regulates this process is ATP. However, the mechanisms involved in extracellular ATP management are poorly understood, particularly in the human dermis. Here, we explore the role, in human fibroblast migration during wound healing, of Pannexin 1 channels and their relationship with purinergic signals and in vivo cell surface filamentous actin dynamics. Using siRNA against Panx isoforms and different Panx1 channel inhibitors, we demonstrate in cultured human dermal fibroblasts that the absence or inhibition of Panx1 channels accelerates cell migration, increases single-cell motility, and promotes actin redistribution. These changes occur through a mechanism that involves the release of ATP to the extracellular space through a Panx1-dependent mechanism and the activation of the purinergic receptor P2X7. Together, these findings point to a pivotal role of Panx1 channels in skin fibroblast migration and suggest that these channels could be a useful pharmacological target to promote damaged skin healing.


Assuntos
Actinas/química , Membrana Celular/metabolismo , Conexinas/metabolismo , Fibroblastos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Pele/metabolismo , Trifosfato de Adenosina/química , Trifosfato de Adenosina/metabolismo , Animais , Movimento Celular , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Isoformas de Proteínas , RNA Interferente Pequeno/metabolismo , Cicatrização
18.
J Neurochem ; 157(6): 1789-1808, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32931038

RESUMO

Pannexin-1 (Panx1) forms plasma membrane channels that allow the exchange of small molecules between the intracellular and extracellular compartments, and are involved in diverse physiological and pathological responses in the nervous system. However, the signaling mechanisms that induce their opening still remain elusive. Here, we propose a new mechanism for Panx1 channel activation through a functional crosstalk with the highly Ca2+ permeable α7 nicotinic acetylcholine receptor (nAChR). Consistent with this hypothesis, we found that activation of α7 nAChRs induces Panx1-mediated dye uptake and ATP release in the neuroblastoma cell line SH-SY5Y-α7. Using membrane permeant Ca2+ chelators, total internal reflection fluorescence microscopy in SH-SY5Y-α7 cells expressing a membrane-tethered GCAMP3, and Src kinase inhibitors, we further demonstrated that Panx1 channel opening depends on Ca2+ signals localized in submembrane areas, as well as on Src kinases. In turn, Panx1 channels amplify cytosolic Ca2+ signals induced by the activation of α7 nAChRs, by a mechanism that seems to involve ATP release and P2X7 receptor activation, as hydrolysis of extracellular ATP with apyrase or blockage of P2X7 receptors with oxidized ATP significantly reduces the α7 nAChR-Ca2+ signal. The physiological relevance of this crosstalk was also demonstrated in neuroendocrine chromaffin cells, wherein Panx1 channels and P2X7 receptors contribute to the exocytotic release of catecholamines triggered by α7 nAChRs, as measured by amperometry. Together these findings point to a functional coupling between α7 nAChRs, Panx1 channels and P2X7 receptors with physiological relevance in neurosecretion.


Assuntos
Células Cromafins/metabolismo , Conexinas/metabolismo , Exocitose/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Receptor Cross-Talk/fisiologia , Receptores Purinérgicos P2X7/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Animais , Quelantes de Cálcio/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Sinalização do Cálcio/fisiologia , Bovinos , Linhagem Celular Tumoral , Células Cromafins/efeitos dos fármacos , Exocitose/efeitos dos fármacos , Humanos , Camundongos , Receptor Cross-Talk/efeitos dos fármacos
19.
Rev. bras. epidemiol ; 24: e210007, 2021. tab
Artigo em Inglês, Espanhol | LILACS, Sec. Est. Saúde SP | ID: biblio-1144140

RESUMO

RESUMEN: Objetivo: Actualizar la estimación de la mortalidad atribuida al consumo de tabaco en Brasil en población de 35 y más años. Métodos: Se aplicó un método dependiente de prevalencia, basado en la fracción atribuida poblacional. Este método estima la mortalidad atribuida a partir de la mortalidad observada en Brasil (fuente: Sistema de Información de Mortalidad del Sistema Único de Salud de Brasil-2016); de las prevalencias de fumadores, exfumadores y nunca fumadores (Encuesta Nacional de Salud de Brasil-2013) y del exceso de riesgo de morir (riesgo relativo) que tienen los fumadores y exfumadores en comparación con los nunca fumadores (5 estudios de cohortes norteamericanos). Se presentan estimaciones de mortalidad atribuida globales, por sexo, grupo de edad (35-54; 55-64; 65-74 y 75 años en adelante) y 3 grupos de enfermedades: tumores malignos, enfermedades cardiometabólicas y respiratorias. Resultados: En 2016, el consumo de tabaco causó con 163.831 muertes en Brasil, el 67% (109.369) fue en hombres y cuatro de cada diez (62.791) sucedieron antes de los 65 años. El 42% de la mortalidad atribuida se asocia a enfermedades cardiometabólicas, seguidas de respiratorias (34%) y tumorales (24%), sin diferencias por sexo. Conclusión: El 14% de las muertes que sucedieron en Brasil durante 2016 en población de 35 y más años se atribuye al consumo de tabaco. Realizar de forma periódica estimaciones de MA es necesario para valorar y fortalecer las leyes de control de tabaquismo implantadas.


ABSTRACT: Objective: To update the estimation of tobacco attributable mortality (AM) in the Brazilian population aged 35 years old and older. Methods: A prevalence-dependent analysis was applied based on the population attributed fraction. This method estimates the tobacco AM taking into account the mortality observed in Brazil (source: Brazilian Mortality Information System - 2016); the prevalence of smokers, former smokers, and never smokers (National Health Survey Brazil - 2013) and the excess of risk of death (relative risk) of smokers and former smokers in comparison to never smokers (derived from 5 North American cohorts). Estimates of overall AM are shown by gender, age group (35-54; 55-64; 65-74; and 75 years old and older) and 3 groups: malignant tumors, cardiometabolic diseases, and respiratory diseases. Results: In 2016, tobacco consumption caused 163,831 deaths in Brazil, 67% (109,369) were in men and four out of ten (62,791) occurred before the age of 65. Without differences by gender, 42% of the AM is associated with cardiometabolic diseases, followed by respiratory diseases (34%) and malignant tumors (24%). Conclusion: During 2016, 14% of the deaths occurred in the Brazilian population aged 35 years old and older were attributed to tobacco consumption. Periodic tobacco AM estimations are mandatory to assess and strengthen smoking control strategies and policies.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Fumar Tabaco/mortalidade , Fumantes/estatística & dados numéricos , Brasil/epidemiologia , Prevalência , Mortalidade , Distribuição por Sexo , Distribuição por Idade , Fumar Tabaco/efeitos adversos
20.
Rev Bras Epidemiol ; 24: e210007, 2020.
Artigo em Espanhol, Inglês | MEDLINE | ID: mdl-33331414

RESUMO

OBJECTIVE: To update the estimation of tobacco attributable mortality (AM) in the Brazilian population aged 35 years old and older. METHODS: A prevalence-dependent analysis was applied based on the population attributed fraction. This method estimates the tobacco AM taking into account the mortality observed in Brazil (source: Brazilian Mortality Information System - 2016); the prevalence of smokers, former smokers, and never smokers (National Health Survey Brazil - 2013) and the excess of risk of death (relative risk) of smokers and former smokers in comparison to never smokers (derived from 5 North American cohorts). Estimates of overall AM are shown by gender, age group (35-54; 55-64; 65-74; and 75 years old and older) and 3 groups: malignant tumors, cardiometabolic diseases, and respiratory diseases. RESULTS: In 2016, tobacco consumption caused 163,831 deaths in Brazil, 67% (109,369) were in men and four out of ten (62,791) occurred before the age of 65. Without differences by gender, 42% of the AM is associated with cardiometabolic diseases, followed by respiratory diseases (34%) and malignant tumors (24%). CONCLUSION: During 2016, 14% of the deaths occurred in the Brazilian population aged 35 years old and older were attributed to tobacco consumption. Periodic tobacco AM estimations are mandatory to assess and strengthen smoking control strategies and policies.


OBJETIVO: Actualizar la estimación de la mortalidad atribuida al consumo de tabaco en Brasil en población de 35 y más años. MÉTODOS: Se aplicó un método dependiente de prevalencia, basado en la fracción atribuida poblacional. Este método estima la mortalidad atribuida a partir de la mortalidad observada en Brasil (fuente: Sistema de Información de Mortalidad del Sistema Único de Salud de Brasil-2016); de las prevalencias de fumadores, exfumadores y nunca fumadores (Encuesta Nacional de Salud de Brasil-2013) y del exceso de riesgo de morir (riesgo relativo) que tienen los fumadores y exfumadores en comparación con los nunca fumadores (5 estudios de cohortes norteamericanos). Se presentan estimaciones de mortalidad atribuida globales, por sexo, grupo de edad (35-54; 55-64; 65-74 y 75 años en adelante) y 3 grupos de enfermedades: tumores malignos, enfermedades cardiometabólicas y respiratorias. RESULTADOS: En 2016, el consumo de tabaco causó con 163.831 muertes en Brasil, el 67% (109.369) fue en hombres y cuatro de cada diez (62.791) sucedieron antes de los 65 años. El 42% de la mortalidad atribuida se asocia a enfermedades cardiometabólicas, seguidas de respiratorias (34%) y tumorales (24%), sin diferencias por sexo. CONCLUSIÓN: El 14% de las muertes que sucedieron en Brasil durante 2016 en población de 35 y más años se atribuye al consumo de tabaco. Realizar de forma periódica estimaciones de MA es necesario para valorar y fortalecer las leyes de control de tabaquismo implantadas.


Assuntos
Fumantes/estatística & dados numéricos , Fumar Tabaco/mortalidade , Adulto , Distribuição por Idade , Idoso , Brasil/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade , Prevalência , Distribuição por Sexo , Fumar Tabaco/efeitos adversos
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