Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Más filtros










Intervalo de año de publicación
1.
Neuron ; 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38518778

RESUMEN

Although bile acids play a notable role in depression, the pathological significance of the bile acid TGR5 membrane-type receptor in this disorder remains elusive. Using depression models of chronic social defeat stress and chronic restraint stress in male mice, we found that TGR5 in the lateral hypothalamic area (LHA) predominantly decreased in GABAergic neurons, the excitability of which increased in depressive-like mice. Upregulation of TGR5 or inhibition of GABAergic excitability in LHA markedly alleviated depressive-like behavior, whereas down-regulation of TGR5 or enhancement of GABAergic excitability facilitated stress-induced depressive-like behavior. TGR5 also bidirectionally regulated excitability of LHA GABAergic neurons via extracellular regulated protein kinases-dependent Kv4.2 channels. Notably, LHA GABAergic neurons specifically innervated dorsal CA3 (dCA3) CaMKIIα neurons for mediation of depressive-like behavior. LHA GABAergic TGR5 exerted antidepressant-like effects by disinhibiting dCA3 CaMKIIα neurons projecting to the dorsolateral septum (DLS). These findings advance our understanding of TGR5 and the LHAGABA→dCA3CaMKIIα→DLSGABA circuit for the development of potential therapeutic strategies in depression.

2.
Sci Rep ; 12(1): 19165, 2022 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-36357435

RESUMEN

Machine learning methods are a novel way to predict and rank donors' willingness to donate blood and to achieve precision recruitment, which can improve the recruitment efficiency and meet the challenge of blood shortage. We collected information about experienced blood donors via short message service (SMS) recruitment and developed 7 machine learning-based recruitment models using PyCharm-Python Environment and 13 features which were described as a method for ranking and predicting donors' intentions to donate blood with a floating number between 0 and 1. Performance of the prediction models was assessed by the Area under the receiver operating characteristic curve (AUC), accuracy, precision, recall, and F1 score in the full dataset, and by the accuracy in the four sub-datasets. The developed models were applied to prospective validations of recruiting experienced blood donors during two COVID-19 pandemics, while the routine method was used as a control. Overall, a total of 95,476 recruitments via SMS and their donation results were enrolled in our modelling study. The strongest predictor features for the donation of experienced donors were blood donation interval, age, and donation frequency. Among the seven baseline models, the eXtreme Gradient Boosting (XGBoost) and Support vector machine models (SVM) achieved the best performance: mean (95%CI) with the highest AUC: 0.809 (0.806-0.811), accuracy: 0.815 (0.812-0.818), precision: 0.840 (0.835-0.845), and F1 score of XGBoost: 0.843 (0.840-0.845) and recall of SVM: 0.991 (0.988-0.994). The hit rate of the XGBoost model alone and the combined XGBoost and SVM models were 1.25 and 1.80 times higher than that of the conventional method as a control in 2 recruitments respectively, and the hit rate of the high willingness to donate group was 1.96 times higher than that of the low willingness to donate group. Our results suggested that the machine learning models could predict and determine the experienced donors with a strong willingness to donate blood by a ranking score based on personalized donation data and demographical details, significantly improve the recruitment rate of blood donors and help blood agencies to maintain the blood supply in emergencies.


Asunto(s)
Donantes de Sangre , COVID-19 , Humanos , COVID-19/epidemiología , Aprendizaje Automático , Intención , Brotes de Enfermedades
3.
Acta Physiologica Sinica ; (6): 136-140, 2006.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-265474

RESUMEN

The Na(+)-Ca(2+) exchange is a major pathway for removal of cytosolic Ca(2+) in cardiac myocytes. To explore the effects of temperature, intracellular Na(+), ATP and pH on Na(+)-Ca(2+) exchange currents (I(Na/Ca)) of intact guinea-pig myocytes, the whole-cell patch-clamp technique was used to record I(Na/Ca) in isolated guinea-pig ventricular myocytes. We found that I(Na/Ca) at 34 degrees C was four times higher than that at 22 degrees C. However, intracellular acidification had no obvious influence on bidirectional I(Na/Ca). At 22~24 degrees C , intracellular ATP depletion and intracellular acidification did not markedly affect bidirectional I(Na/Ca) either. At 34~37 degrees C , intracellular ATP depletion and intracellular acidification synergistically inhibited the outward and inward currents of I(Na/Ca), and blocked the inward currents of I(Na/Ca)more potently than the outward currents of I(Na/Ca). The effect of ATP on I(Na/Ca) is temperature-dependent. Intracellular higher sodium increased the outward currents of I(Na/Ca) however it did not increase, even sometimes decreased the inward currents of I(Na/Ca). These results suggest that intracellular ATP depletion and intracellular acidification synergistically impair Ca(2+) extrusion via forward mode Na(+)-Ca(2+) exchange, and intracellular sodium overload increases Ca(2+) influx via reverse mode Na(+)-Ca(2+) exchange, leading to calcium overload respectively.


Asunto(s)
Animales , Masculino , Adenosina Trifosfato , Fisiología , Calcio , Metabolismo , Cobayas , Ventrículos Cardíacos , Biología Celular , Patología , Concentración de Iones de Hidrógeno , Hipoxia , Líquido Intracelular , Fisiología , Miocitos Cardíacos , Metabolismo , Fisiología , Técnicas de Placa-Clamp , Sodio , Fisiología , Intercambiador de Sodio-Calcio , Fisiología , Temperatura
4.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-251890

RESUMEN

Two isomers of nitrochlorobenzene (o-, and p-NCB) were treated by a Pd/Fe catalyst in aqueous solutions through catalytic amination and dechlorination. Nitrochlorobenzenes are rapidly converted to form chloroanilines (CAN) first through an amination process, and then rapidly dechlorinated to become aniline (AN) and Cl(-), without the involvement of any other intermediate reaction products. The amination and dechlorination reaction are believed to take place predominantly on the surface site of the Pd/Fe catalysts. The dechlorination rate of the reductive degradation of the two isomers of nitrochlorobenzene (o-, and p-NCB) in the presence of Pd/Fe as a catalyst was measured experimentally. In all cases, the reaction rate constants were found to increase with the decrease in the Gibbs free energy (correlation with the activation energy) of NCBs formation; the activation energy of each dechlorination reaction was measured to be 95.83 and 77.05 kJ/mol, respectively for o- and p-NCB. The results demonstrated that p-NCBs were reduced more easily than o-NCBs.


Asunto(s)
Catálisis , Residuos Industriales , Hierro , Química , Isomerismo , Cinética , Metales , Química , Nitrobencenos , Química , Paladio , Química , Relación Estructura-Actividad , Eliminación de Residuos Líquidos , Métodos , Agua , Química , Purificación del Agua , Métodos
5.
Acta Pharmaceutica Sinica ; (12): 509-513, 2004.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-302775

RESUMEN

<p><b>AIM</b>To elucidate the possible mechanisms underlying antiarrhythmia of the non-selective Na+/H+ exchanger inhibitor--amiloride.</p><p><b>METHODS</b>Single ventricular cells were isolated using a double-enzyme method. Effects of amiloride on voltage-dependent potassium and calcium currents in isolated guinea pig ventricular myocyte were recorded by using whole-cell patch clamp techniques.</p><p><b>RESULTS</b>Exposure to amiloride (10 -100 micromol x L(-1)), the L-type and T-type calcium currents were depressed. Amiloride resulted in a concentration-dependent inhibition of peak (Ca,L), But amiloride did not change the shape of their I - V curves. It only decreased the amplitudes of the currents of the two types. When myocytes were incubated with 100 micromol x L(-1) amiloride, I(Kr) was slightly depressed and I(Ks) did not change. Amiloride (1 - 100 micromol x L(-10) depressed I(K1) in a concentration-dependent manner.</p><p><b>CONCLUSION</b>Amiloride depressed potassium and calcium currents, which may give support to its uses in some diseases of the cardiovascular system.</p>


Asunto(s)
Animales , Femenino , Masculino , Amilorida , Farmacología , Antiarrítmicos , Farmacología , Canales de Calcio Tipo L , Canales de Calcio Tipo T , Separación Celular , Cobayas , Ventrículos Cardíacos , Biología Celular , Miocitos Cardíacos , Técnicas de Placa-Clamp , Canales de Potasio de Rectificación Interna , Canales de Potasio con Entrada de Voltaje , Intercambiadores de Sodio-Hidrógeno
6.
Acta Pharmaceutica Sinica ; (12): 813-816, 2003.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-266578

RESUMEN

<p><b>AIM</b>To observe the effects of ouabain on vascular smooth muscle (VSM) of the guinea pig and its interactions with Ca2+ and norepinephrine (NE).</p><p><b>METHODS</b>Using isolated thoracic aortic ring of the guinea pig, the degrees of contractile activity of drugs were recorded.</p><p><b>RESULTS</b>Ouabain showed a direct contractile effect in a concentration-dependent manner on thoracic aortic ring of guinea pig. Ouabain shifted the NE dose-response curve to the left without changing in the maxium response. Ouabain shifted the CaCl2 dose-response curve to the left and upward, increased the maximum response to Ca2+; In Ca(2+)-free medium, the ouabain induced contraction was abolished, an increase in extracellular Ca2+ restored the response; nifedipine and verapamil abolished the ouabain induced contraction.</p><p><b>CONCLUSION</b>The ouabain induced contraction is mainly dependent on the extracellular Ca2+ concentration, independent on the presence of endothelia of aorta, suggesting that Ca2+ antagonist may treat the hypertension induced by ouabain. Ouabain, NE and CaCl2 have synergetic contractile effects, suggesting that the synergetic contractile effects of ouabain and NE may contribute to the generation and development of hypertension.</p>


Asunto(s)
Animales , Femenino , Masculino , Aorta Torácica , Calcio , Metabolismo , Bloqueadores de los Canales de Calcio , Farmacología , Cloruro de Calcio , Farmacología , Sinergismo Farmacológico , Cobayas , Contracción Muscular , Músculo Liso Vascular , Nifedipino , Farmacología , Norepinefrina , Farmacología , Ouabaína , Farmacología , Verapamilo , Farmacología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...