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1.
Front Endocrinol (Lausanne) ; 13: 1013338, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36440188

RESUMEN

Background: Bone metastases (BM) from malignant tumors could disrupt the balance between osteoclasts and osteoblasts and affect bone homeostasis. Malignant breast cancer (BC) is rare in male patients, and co-occurrence of BM is even rarer. Given its low incidence, there is limited research evaluating risk and prognosis. Despite the widespread application of nomograms to predict uncommon malignancies, no studies have constructed predictive models focusing on the diagnosis and prognosis of male breast cancer with bone metastases (MBCBM). Methods: This study selected all male breast cancer patients (MBC) between 2010 and 2019 in the Surveillance, Epidemiology, and End Results (SEER) database. We used simple and multivariate Logistic regression analyses to identify independent risk factors for BM in MBC patients. Then simple and multivariate Cox regression analyses were employed to determine the independent prognostic factors for overall survival (OS) and cancer-specific survival (CSS) in MBCBM patients. We established and validated three new nomograms based on these independent factors. Result: A total of 4187 MBC patients were included, with 191 (4.56%) having bone metastases at the time of diagnosis. The independent risk factors of BM in MBC patients included age, tumor size, marital status, T stage, and N stage. In MBCBM patients, independent prognostic factors for OS and CSS were both age, T stage, ER status, PR status, and surgery. The concordance index (C-index), the area under the curve (AUC) of the receiver operating characteristic curve (ROC), the calibration curve, and the decision curve analysis (DCA) confirmed that these three nomograms could accurately predict the diagnosis and prognosis of MBCBM patients with excellent discrimination and clinical utility superior to the TNM staging system. We then established two prognostic-based risk stratification systems and three visualized dynamic nomograms that could be applied in clinical practice. Conclusion: In conclusion, this study aimed to establish and validate an accurate novel nomogram to objectively predict the diagnosis and prognosis of MBCBM patients. On this basis, prognostic-based risk stratification systems and visualized dynamic nomograms were constructed to facilitate doctors and patients to quantify individual BM risk probability and survival probability to assist in personalized risk assessment and clinical decision-making.


Asunto(s)
Neoplasias Óseas , Neoplasias de la Mama Masculina , Humanos , Masculino , Femenino , Nomogramas , Neoplasias de la Mama Masculina/diagnóstico , Programa de VERF , Pronóstico , Neoplasias Óseas/diagnóstico , Medición de Riesgo/métodos
2.
Medicine (Baltimore) ; 100(6): e24583, 2021 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-33578557

RESUMEN

ABSTRACT: Lumbar disc prostheses have been used increasingly in recent years. The successful design of lumbar disc prostheses depends on accurate morphometric parameters. However, the morphologic dimensions of lumbar endplate area have not been investigated in Chinese population.A total of 1800 lumbar endplates were retrospectively accessed in 150 Chinese adults. Eighteen parameters of each lumbar segment were measured by three-dimensional computed tomography reconstructions from T12/L1 to L5/S1. These obtained parameters were compared between genders, bilateral sides, vertebral segments, and different populations.Endplate length and width increased in general, and there was a significant decrease for length/width ratio from T12 to S1 (P = .03). The average concavity depth of the lower lumbar endplate (2.09 ±â€Š0.93 mm) was usually larger than that of the upper lumbar endplate (1.61 ±â€Š0.74 mm) (P = .02). The percentage of the most concave point of the upper and lower lumbar endplate was 50.01 ±â€Š10.76% and 56.41 ±â€Š9.93%, respectively. Anterior, medium, or posterior intervertebral endplate height was severally 10.01 ±â€Š1.98 mm, 10.46 ±â€Š2.03 mm, and 6.41 ±â€Š1.74 mm, and increased among vertebral segments (P = .01).The intervertebral endplate angle significantly increased from T12-L1 to L5-S1 (P = .01). Parameters displayed significant difference between genders. The morphometric parameters of different populations also showed differences.In conclusion, there is a morphologic discrepancy in dimensions of lumbar endplate regarding genders, vertebral segments, and different populations. It is essential to design the lumbar disc prosthesis suited for Chinese patients specially, for which the morphometric parameters in our study can be utilized.


Asunto(s)
Disco Intervertebral , Vértebras Lumbares/diagnóstico por imagen , Prótesis e Implantes , Diseño de Prótesis , Adulto , Femenino , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Valores de Referencia , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Adulto Joven
3.
Prog Neurobiol ; 82(1): 1-10, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17363132

RESUMEN

Toosendanin (TSN) is a triterpenoid extracted from Melia toosendan Sieb et Zucc, which was used as a digestive tract-parasiticide and agricultural insecticide in ancient China. TSN was demonstrated to be a selective presynaptic blocker and an effective antibotulismic agent. By interfering with neurotransmitter release through an initial facilitation followed by a subsequent depression, TSN eventually blocks synaptic transmission at both the neuro-muscular junction and central synapses. Despite sharing some similar actions with botulinum neurotoxin (BoNT), TSN has a marked antibotulismic effect in vivo and in vitro. Studies suggest that the antibotulismic effect of TSN is achieved by preventing BoNT from approaching its enzymatic substrate, the SNARE protein. It is also found that TSN can induce differentiation and apoptosis in several cell lines, and suppress proliferation of various human cancer cells. TSN inhibits various K(+)-channels, selectively facilitates Ca(2+)-influx via L-type Ca(2+) channels and increases intracellular Ca(2+) concentration ([Ca(2+)](i)). The TSN-induced [Ca(2+)](i) increase and overload could be responsible for the TSN-induced biphasic effect on transmitter release, cell differentiation, apoptosis as well as the cytoxicity of TSN.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Medicina Tradicional China , Animales , Apoptosis/efectos de los fármacos , Botulismo/tratamiento farmacológico , Canales de Calcio/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Humanos , Transmisión Sináptica/efectos de los fármacos
4.
Acta Pharmacol Sin ; 27(1): 66-70, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16364212

RESUMEN

AIM: Botulinum neurotoxins (BoNT) abort the process of neurotransmitter release at presynaptic motor nerve terminals, causing muscle paralysis. The ability of botulinum toxin to produce its effect is dependent on the ability of the light chain to cleave the SNARE proteins associated with transmitter release. Translocation of the light chain protease through the heavy chain-formed channel is a pivotal step in the intoxication process. Toosendanin (TSN), a triterpenoid derivative extracted from a Chinese traditional medicine, has been demonstrated to be an effective cure for experimental botulism. This study was designed to explore the antibotulismic mechanisms of toosendanin. METHODS: The inside-out single-channel recording patch-clamp technique was used to record the BoNT/A-induced currents in the presence and absence of TSN. RESULTS: Channel formation was delayed and the sizes of the channels were reduced in the TSN-treated PC12 cell membrane. CONCLUSION: The antibotulismic effect of TSN might occur via interference with toxin translocation.


Asunto(s)
Toxinas Botulínicas Tipo A/antagonistas & inhibidores , Membrana Celular/fisiología , Medicamentos Herbarios Chinos/farmacología , Canales Iónicos/efectos de los fármacos , Animales , Toxinas Botulínicas Tipo A/metabolismo , Membrana Celular/efectos de los fármacos , Medicamentos Herbarios Chinos/aislamiento & purificación , Melia/química , Células PC12 , Plantas Medicinales/química , Transporte de Proteínas , Ratas
5.
Toxicon ; 45(1): 53-60, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15581683

RESUMEN

Toosendanin is a triterpenoid derivative extracted from Melia toosendan Sieb et Zucc. Previous studies demonstrated that toosendanin could block neurotransmission and stimulate PC12 cell into differentiation and apoptosis. These actions of toosendanin were suggested to result from a continuous increase in Ca2+ influx, which led to intracellular Ca2+ overload. Here, we observed the long-term effect of toosendanin on Ca2+ channels in NG108-15 cells by whole-cell patch-clamp recording. Obtained data showed that a prolonged exposure to toosendanin induced a continuous increase in the Ca2+ influx in a concentration and time-dependent manner while a brief treatment induced an irreversible increase in Ca2+ influx in differentiated NG108-15 cells. The nifedipine-sensitive L-type currents were significantly increased after exposure to TSN while the nifedipine-resistant or omega-conotoxin MVIIC-sensitive currents were not affected.


Asunto(s)
Canales de Calcio/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Animales , Bario/fisiología , Calcio/fisiología , Bloqueadores de los Canales de Calcio/farmacología , Canales de Calcio/metabolismo , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Potenciales de la Membrana/efectos de los fármacos , Nifedipino/farmacología , Factores de Tiempo , omega-Conotoxinas
6.
Eur J Pharmacol ; 501(1-3): 71-8, 2004 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-15464064

RESUMEN

Toosendanin, a triterpenoid derivative extracted from Melia toosendan Sieb et Zucc, was demonstrated to be potentially useful in medical and scientific researches. Here, we investigated the effects of toosendanin on L-type voltage-dependent Ca(2+) channels in cultured neonatal rat ventricular cells, using whole-cell patch-clamp method. Toosendanin irreversibly increased L-type Ca(2+) current (I(Ca(L))) in a concentration-dependent manner and shifted the maximum of the current/voltage relationship from 8.3+/-3.7 to 1.7+/-3.7 mV, without modifying the threshold potential of the current. Toosendanin shifted the steady-state activation and inactivation curves to the left. The deactivation kinetics of the I(Ca(L)) was significantly slowed by toosendanin while the activation kinetics was not affected. The cells pretreated with 100 nM 1,4-dihydro-2,6-dimethyl-5-nitro-4-[2-(trifluoromethyl)phenyl]-3-pyridinecarboxylic acid methyl ester (S(-)-BayK8644) still respond to further addition of 87 microM toosendanin, and vice versa. These results prove toosendanin to be a novel L-type Ca(2+) channel agonist, which possesses a distinct binding site from BayK8644.


Asunto(s)
Animales Recién Nacidos/metabolismo , Agonistas de los Canales de Calcio/farmacología , Canales de Calcio Tipo L/fisiología , Medicamentos Herbarios Chinos/farmacología , Miocitos Cardíacos/efectos de los fármacos , Triterpenos/farmacología , Animales , Células Cultivadas , Relación Dosis-Respuesta a Droga , Ventrículos Cardíacos/citología , Ventrículos Cardíacos/efectos de los fármacos , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/fisiología , Miocitos Cardíacos/fisiología , Ratas , Ratas Sprague-Dawley , Función Ventricular
7.
Neurosci Res ; 49(2): 197-203, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15140562

RESUMEN

Toosendanin, a triterpenoid derivative extracted from Melia toosendan Sieb et Zucc, was demonstrated to be a selective presynaptic blocker and an effective antibotulismic agent in previous studies. Here, we observed its effects on Ca(2+) channels in NG108-15 cells by whole-cell patch-clamp recording. Obtained data showed that toosendanin concentration dependently increased the high-voltage-activated (HVA) Ca(2+) current with an EC(50) of 5.13 microM in differentiated NG108-15 cells. The enhancement effect was still observed when the cells were pretreated with 5 microM omega-conotoxin MVIIC. However, when the cells were preincubated with 5 microM nifedipine or 10 microM verapamil-containing solution, the effect was absent. In undifferentiated NG108-15 cells, which only express T-type Ca(2+) channels, toosendanin did not affect Ca(2+) currents. These results show that toosendanin increases Ca(2+) influx in NG108-15 cells via L-type Ca(2+) channels.


Asunto(s)
Canales de Calcio Tipo L/fisiología , Calcio/metabolismo , Medicamentos Herbarios Chinos/farmacología , Animales , Bario/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Canales de Calcio Tipo L/efectos de los fármacos , Diferenciación Celular/fisiología , Línea Celular , Relación Dosis-Respuesta a Droga , Potenciales de la Membrana/efectos de los fármacos , Ratones , Neuroblastoma , Técnicas de Placa-Clamp/métodos
8.
Neurol Res ; 25(1): 58-62, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12564127

RESUMEN

The antibodies against pre-synaptic membrane receptor (PsmR) and acetylcholine receptor (AChR) in serum samples of myasthenia gravis (MG) patients and healthy donors were tested by enzyme-linked immunosorbent assays (ELISA). The serum samples of eight MG patients with different autoantibodies and those of six healthy donors without these two kinds of autoantibodies were collected to investigate their effects on the peri-neurially recorded membrane currents at mouse motor nerve terminals. After inhibition of both fast and Ca(2+)-dependent K+ currents by tetra-ethylammonium (TEA), a positive wave was revealed, which was a balance of the slow K+(Ik,s) and Ca2+ currents (ICa). Application of anti-PsmR antibody negative MG sera and healthy donor sera, whether anti-AChR antibody positive or negative, did not affect the positive wave. However, the positive wave shifted to prolonged Ca(2+)-plateau when adding two of four anti-PsmR antibody positive serum samples from MG patients, indicating an inhibition of Ik,s by anti-PsmR antibody positive sera. Meanwhile, all serum samples derived from either patients or healthy donors did not affect INa.


Asunto(s)
Autoanticuerpos/inmunología , Potenciales de la Membrana , Neuronas Motoras/fisiología , Miastenia Gravis/sangre , Adolescente , Adulto , Animales , Autoanticuerpos/farmacología , Células Cultivadas , Niño , Preescolar , Electrofisiología , Humanos , Potenciales de la Membrana/efectos de los fármacos , Ratones , Persona de Mediana Edad , Neuronas Motoras/efectos de los fármacos , Miastenia Gravis/inmunología , Canales de Potasio/efectos de los fármacos , Canales de Potasio/fisiología , Receptores Presinapticos/efectos de los fármacos , Receptores Presinapticos/fisiología , Membranas Sinápticas/efectos de los fármacos , Membranas Sinápticas/fisiología
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