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1.
Nature ; 594(7861): 33-36, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34002091

RESUMEN

The extension of the cosmic-ray spectrum beyond 1 petaelectronvolt (PeV; 1015 electronvolts) indicates the existence of the so-called PeVatrons-cosmic-ray factories that accelerate particles to PeV energies. We need to locate and identify such objects to find the origin of Galactic cosmic rays1. The principal signature of both electron and proton PeVatrons is ultrahigh-energy (exceeding 100 TeV) γ radiation. Evidence of the presence of a proton PeVatron has been found in the Galactic Centre, according to the detection of a hard-spectrum radiation extending to 0.04 PeV (ref. 2). Although γ-rays with energies slightly higher than 0.1 PeV have been reported from a few objects in the Galactic plane3-6, unbiased identification and in-depth exploration of PeVatrons requires detection of γ-rays with energies well above 0.1 PeV. Here we report the detection of more than 530 photons at energies above 100 teraelectronvolts and up to 1.4 PeV from 12 ultrahigh-energy γ-ray sources with a statistical significance greater than seven standard deviations. Despite having several potential counterparts in their proximity, including pulsar wind nebulae, supernova remnants and star-forming regions, the PeVatrons responsible for the ultrahigh-energy γ-rays have not yet been firmly localized and identified (except for the Crab Nebula), leaving open the origin of these extreme accelerators.

2.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58(6): 839-846, 2024 Jun 06.
Artículo en Zh | MEDLINE | ID: mdl-38955731

RESUMEN

Objective: To investigate the association of urinary cadmium levels with peripheral leukocyte classification counts among middle-aged and older adults aged 40 to 89 years in selected areas of China. Methods: The research was based on the survey of the impact of soil quality of agricultural land on human health in typical areas conducted in 2019-2020. A total of 5 600 middle-aged and older adults aged 40 to 89 years were included by using a multi-stage stratified random sampling method. Baseline characteristics of the subjects were collected and physical examinations were performed. Random midstream urine was collected to measure urinary cadmium and urinary creatinine and fasting venous blood was collected to measure the leukocyte count, neutrophil count, lymphocyte count, monocyte count and eosinophil count. The linear mixed effect model was used to analyse the association of urinary cadmium levels with leukocyte classification counts, and the dose-response relationship between them was analyzed by using the restricted cubic spline (RCS) function. Results: The age of the subjects was (63.17±12.02) years; 2 851 (50.91%) were males; and the M (Q1, Q3) of urinary creatinine-corrected urinary cadmium levels was 2.69 (1.52, 4.69) µg/g·creatinine. After adjusting for confounding factors, the results of linear mixed effects model analysis showed that for each 1-unit increase in urinary creatinine-corrected urinary cadmium level, the percentage change [% (95%CI)] of leukocyte count and lymphocyte count was -1.70% (-2.61%, -0.79%) and -1.57% (-2.86%, -0.26%), respectively. RCS function showed a negative linear relationship between urinary creatinine-corrected urinary cadmium levels and leukocyte counts and lymphocyte counts, respectively (all Pnon-linear>0.05). Conclusion: Urinary cadmium levels are negatively associated with leukocyte count and lymphocyte count among middle-aged and older adults aged 40 to 89 years in selected areas of China.


Asunto(s)
Cadmio , Humanos , Cadmio/orina , Persona de Mediana Edad , China , Anciano , Masculino , Recuento de Leucocitos , Femenino , Adulto , Anciano de 80 o más Años , Creatinina/orina
3.
Zhonghua Gan Zang Bing Za Zhi ; 32(4): 332-339, 2024 Apr 20.
Artículo en Zh | MEDLINE | ID: mdl-38733188

RESUMEN

Objective: To evaluate the long-term efficacy of percutaneous microwave ablation (MWA) therapy for hepatocellular carcinoma. Methods: 2054 cases with Barcelona Clinic Liver Cancer (BCLC) stage 0~B at the Fifth Medical Center of the Chinese People's Liberation Army General Hospital from January 2006 to September 2020 were retrospectively collected. All patients were followed up for at least 2 years. The primary endpoint of overall survival and secondary endpoints (tumor-related survival, disease-free survival, and postoperative complications) of patients treated with ultrasound-guided percutaneous MWA were analyzed. Kaplan-Meier method was used for stratified survival rate analysis. Fine-and-Gray competing risk model was used to analyze overall survival. Results: A total of 5 503 HCC nodules [mean tumor diameter (2.6±1.6) cm] underwent 3 908 MWAs between January 2006 and September 2020, with a median follow-up time of 45.6 (24.0 -79.2) months.The technical effectiveness rate of 5 375 tumor nodules was 97.5%. The overall survival rates at 5, 10, and 15-years were 61.6%, 38.8%, and 27.0%, respectively. The tumor-specific survival rates were 67.1%, 47.2%, and 37.7%, respectively. The free tumor survival rates were 25.8%, 15.7%, and 9.9%, respectively. The incidence rate of severe complications was 2.8% (108/3 908). Further analysis showed that the technical effectiveness and survival rate over the passing three time periods from January 2006-2010, 2011-2015, and 2016-September 2020 were significantly increased, with P < 0.001, especially for liver cancer 3.1~5.0 cm (P < 0.001). Conclusion: Microwave ablation therapy is a safe and effective method for BCLC stage 0-B, with significantly enhanced technical efficacy and survival rate over time.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Microondas , Humanos , Neoplasias Hepáticas/cirugía , Neoplasias Hepáticas/terapia , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/cirugía , Microondas/uso terapéutico , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento , Supervivencia sin Enfermedad , Ablación por Catéter/métodos , Femenino , Complicaciones Posoperatorias/epidemiología , Masculino , Persona de Mediana Edad
4.
Phys Rev Lett ; 128(5): 051102, 2022 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-35179919

RESUMEN

Recently, the LHAASO Collaboration published the detection of 12 ultrahigh-energy γ-ray sources above 100 TeV, with the highest energy photon reaching 1.4 PeV. The first detection of PeV γ rays from astrophysical sources may provide a very sensitive probe of the effect of the Lorentz invariance violation (LIV), which results in decay of high-energy γ rays in the superluminal scenario and hence a sharp cutoff of the energy spectrum. Two highest energy sources are studied in this work. No signature of the existence of the LIV is found in their energy spectra, and the lower limits on the LIV energy scale are derived. Our results show that the first-order LIV energy scale should be higher than about 10^{5} times the Planck scale M_{Pl} and that the second-order LIV scale is >10^{-3}M_{Pl}. Both limits improve by at least one order of magnitude the previous results.

5.
Phys Rev Lett ; 126(24): 241103, 2021 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-34213924

RESUMEN

We report the discovery of an extended very-high-energy (VHE) gamma-ray source around the location of the middle-aged (207.8 kyr) pulsar PSR J0622+3749 with the Large High-Altitude Air Shower Observatory (LHAASO). The source is detected with a significance of 8.2σ for E>25 TeV assuming a Gaussian template. The best-fit location is (right ascension, declination) =(95.47°±0.11°,37.92°±0.09°), and the extension is 0.40°±0.07°. The energy spectrum can be described by a power-law spectrum with an index of -2.92±0.17_{stat}±0.02_{sys}. No clear extended multiwavelength counterpart of the LHAASO source has been found from the radio to sub-TeV bands. The LHAASO observations are consistent with the scenario that VHE electrons escaped from the pulsar, diffused in the interstellar medium, and scattered the interstellar radiation field. If interpreted as the pulsar halo scenario, the diffusion coefficient, inferred for electrons with median energies of ∼160 TeV, is consistent with those obtained from the extended halos around Geminga and Monogem and much smaller than that derived from cosmic ray secondaries. The LHAASO discovery of this source thus likely enriches the class of so-called pulsar halos and confirms that high-energy particles generally diffuse very slowly in the disturbed medium around pulsars.

6.
Zhonghua Fu Chan Ke Za Zhi ; 56(9): 616-621, 2021 Sep 25.
Artículo en Zh | MEDLINE | ID: mdl-34547862

RESUMEN

Objective: To investigate the present situation of unintended pregnancy within two years postpartum and its influencing factors in China. Methods: Participants who delivered a live birth at 60 hospitals in 15 provinces in the eastern, central and western regions of China during July 2015 to June 2016 were interviewed by using structured questionnaire. Information on occurrence of unintended pregnancy within 2 years after delivery, postpartum contraceptive use, sexual resumption, breastfeeding, and women's socio-demographic characteristics, and so on, were collected. Life-table analysis, cluster log-rank tests and a 2-level Cox regression model were used for data analysis. Results: A total of 18 045 postpartum women were investigated. The cumulative 1- and 2-year unintended pregnancy rates after delivery were 5.3% (95%CI: 4.5%-6.1%) and 13.1% (95%CI: 11.3%-14.8%), respectively. Cox regression model analysis showed that the risk of unintended pregnancy within 2 years postpartum were increased in younger women, ethnic minorities, women with abortion history, and those who had a vaginal delivery with short lactation time and late postpartum contraceptive initiation (all P<0.01). The risk of postpartum unintended pregnancy was not associated with geographic regions and hospitals where women gave a birth (all P>0.05). Conclusions: In China, the risk of unintended pregnancy within 2 years after delivery is relatively high. Service institutions and service providers should improve the quality of postpartum family planning services, promote the use of high effect contraceptive methods, and educate women to use a method at the time of their sexual resumption or even before.


Asunto(s)
Anticoncepción , Embarazo no Planeado , China/epidemiología , Servicios de Planificación Familiar , Femenino , Humanos , Incidencia , Embarazo
7.
Public Health ; 180: 90-99, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31875529

RESUMEN

OBJECTIVE: We aimed to predict population composition, mortality, sociodemographic index (SDI), and cause-specific disability-adjusted life year (DALY) rate in China from 2018 through 2021. STUDY DESIGN: Using the time series method autoregressive integrated moving average (ARIMA) models on all available data, mainly Statistics Year Report by the Global Burden of Disease Study 2017, we predicted populations, deaths, DALYs attributable to disease conditions, and injuries (causes) for China from 2018 through 2021 at levels 0, 1, 2, and 3. METHODS: The time series method ARIMA models was used on history data. RESULTS: The predicted total population and SDI in China are increasing from 2018 through 2021. The under-5 mortality is decreasing; from 10.24% to 0.65% in the period 1990-2021. The all-cause DALY rate decreases. The top causes of DALY rate are non-communicable diseases (level 1), cardiovascular diseases (level 2), and stroke (level 3). For the leading 22 level 2 causes in 2018, the trend of ranking in 2021 is as follows: unchanged, 15; increasing, 4; and decreasing, 3. For the leading 169 level 3 causes in 2018, the trend of ranking in 2021 is: as follows: unchanged, 49; increasing, 63; and decreasing 57. CONCLUSIONS: Cause-specific and time-dependent health policy should be steered to reduce the major burden focuses and to improve population health.


Asunto(s)
Personas con Discapacidad/estadística & datos numéricos , Años de Vida Ajustados por Calidad de Vida , Enfermedades Cardiovasculares/epidemiología , China/epidemiología , Humanos , Modelos Estadísticos , Enfermedades no Transmisibles/epidemiología , Accidente Cerebrovascular/epidemiología
8.
Zhonghua Yan Ke Za Zhi ; 56(5): 343-348, 2020 May 11.
Artículo en Zh | MEDLINE | ID: mdl-32450666

RESUMEN

Objective: To observe the preliminary clinical effect of intraocular lens optic capture through posterior continuous curvilinear capsulorhexis in the treatment of pediatric cataract. Methods: It was a retrospective case series study. Forty-three eyes of 28 children underwent posterior continuous curvilinear capsulorhexis with posterior chamber intraocular lens optic capture to treat cataract from June 2017 to October 2018 in Qingdao Eye Hospital. Postoperative best corrected visual acuity, diopters, intraocular pressure, the position of intraocular lens, and postoperative complications were assessed. The distribution of preoperative and postoperative best corrected visual acuity was analyzed by Fisher's exact probability test. Results: Twenty-eight patients were 14 females and 14 males aged from 2 years old to 12 years old [mean age, (7±4) years]. All intraocular lenses were successfully captured in the posterior capsule. Patients were followed-up for 6.0 to 12.0 months (mean, 8.4 months). Except 2 eyes from one uncooperative child, the distribution of preoperative and postoperative best corrected visual acuity (<0.1, 0.1-<0.3, 0.3-<0.5, ≥0.5) had a significant difference (17, 17, 4, 3 eyes vs. 4, 4, 5, 28 eyes, P<0.01). At the last postoperative follow-up visit, the mean spherical equivalent was (0.21±0.74) D. Transient intraocular hypertension occurred in 3 eyes at 1 week after surgery and was controlled with stopping the use of corticosteroid eyedrops. No visual axis opacification or intraocular lens decentration or tilt was observed during the follow-up period. No other complications such as iris synechia, secondary glaucoma, retinal detachment, and cystoid macular edema were observed. Conclusions: Posterior continuous curvilinear capsulorhexis with intraocular lens optic capture is a safe and effective technique to treat pediatric cataract. It has a significant effect on the prevention of visual axis opacification after cataract surgery in children. (Chin J Ophthalmol, 2020, 56: 343-348).


Asunto(s)
Capsulorrexis , Extracción de Catarata , Catarata , Lentes Intraoculares , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Implantación de Lentes Intraoculares , Masculino , Complicaciones Posoperatorias , Estudios Retrospectivos
9.
J Anesth ; 30(3): 410-9, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26762997

RESUMEN

PURPOSE: Heat stress stimulation can cause various injuries in human umbilical vein endothelial cells (HUVEC), including apoptotic cell death and an increase in cell permeability. Propofol (PPF), a commonly used anesthetic, is known to have an important role in antioxidation as well as organ protection. Therefore, our aim is to evaluate the protective effects of PPF on heat stress (HS)-induced oxidative stress injury and its possible mechanism of action. METHODS: For HS + PPF, cells were treated with propofol followed by 2 h heat stress at 43 °C and then 4 h incubation under normal conditions. For propofol treatment, HUVEC were cultured in serum-free Dulbecco's modified Eagle medium supplemented with 0, 10, 25, or 50 µM propofol for 6 h under normal conditions. RESULTS: During the study, we found that, in HS-induced cellular damage, the protective effect of propofol was related closely with its antioxidation properties. We further revealed that heat stress significantly reduced the level of manganese superoxide demutase (MnSOD) and Cu/Zn SOD, but that propofol could inhibit the reduction of MnSOD only. Transfection of HUVEC with MnSOD small interfering RNA (siRNA) markedly decreased the expression of MnSOD, and the protective effect of propofol in the MnSOD siRNA clones was significantly reduced. CONCLUSION: Propofol protected the heat stress-injured cells, at least partly, through upregulating MnSOD expression, effectively reducing the direct or indirect cell damage caused by oxidative stress.


Asunto(s)
Anestésicos Intravenosos/farmacología , Antioxidantes/farmacología , Trastornos de Estrés por Calor/enzimología , Trastornos de Estrés por Calor/prevención & control , Propofol/farmacología , Superóxido Dismutasa/metabolismo , Apoptosis/efectos de los fármacos , Caspasas/metabolismo , Femenino , Células Endoteliales de la Vena Umbilical Humana , Humanos , Estrés Oxidativo/efectos de los fármacos , ARN Interferente Pequeño/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/genética
10.
Zhonghua Fu Chan Ke Za Zhi ; 51(8): 576-80, 2016 Aug 25.
Artículo en Zh | MEDLINE | ID: mdl-27561935

RESUMEN

OBJECTIVE: To investigate the factors affecting the vaginal birth after cesarean (VBAC). METHODS: Totaly 298 women who underwent trial of labor after cesarean section (TOLAC) from Jan 2015 to Dec 2015 were recruited from Beijing Obstetrics and Gynecology Hospital, FuXing Hospital, Tongzhou Maternal and Child Health Hospital of Beijing, the Second Affiliated Hospital of Chongqing Medical University and the People's Hospital of Chengyang District of Qingdao. The maternal age, the interval from the last cesarean section, the body mass index (BMI) before pregnancy, the weight gain during pregnancy, the way into labor, the Bishop score before labor, the gestational age and the birth weight of the neonate were recorded in a self-made form. The factors affecting VBAC were analyzed by univariate analysis and multivariable logistic regression. RESULTS: (1)The incidence of VBAC, uterine rupture, postpartum hemorrhage and neonatal asphyxia were 70.5% (210/298), 2.7% (8/298), 9.4% (28/298) and 1.3% (4/298), respectively. No maternal death and perinatal death occurred. (2)The univariate analysis suggested that the maternal age, the BMI before pregnancy, the Bishop score before labor, the labor induction, the gestational age at delivery and the neonatal weight were factors affecting VBAC. The maternal age and the Bishop score before labor were significantly higher in the VBAC group than in the unsuccessful TOLAC group(P<0.05). While the BMI before pregnancy, the induction rate, the gestational weeks at delivery and the birth weight of the neonate were significantly lower in the VBAC group than in the unsuccessful TOLAC group (P<0.05). Multivariable logistic regression analysis showed that successful VBAC was affected by the maternal age, the BMI before pregnancy, the Bishop score before labor and the birth weight of the neonates(P<0.05). CONCLUSION: The maternal age, the BMI before pregnancy, the Bishop score before labor and the birth weight of neonate are the main factors affecting VBAC.


Asunto(s)
Índice de Masa Corporal , Cesárea/estadística & datos numéricos , Edad Materna , Esfuerzo de Parto , Parto Vaginal Después de Cesárea/estadística & datos numéricos , Peso al Nacer , China/epidemiología , Femenino , Edad Gestacional , Humanos , Recién Nacido , Trabajo de Parto Inducido , Modelos Logísticos , Obesidad/complicaciones , Hemorragia Posparto , Embarazo , Resultado del Embarazo , Estudios Retrospectivos , Rotura Uterina , Parto Vaginal Después de Cesárea/efectos adversos , Aumento de Peso , Adulto Joven
11.
Genet Mol Res ; 13(1): 415-24, 2014 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-24535868

RESUMEN

Our research demonstrated the potential for mouse bone marrow mesenchymal stem cells (mBMMSCs) to differentiate into hepatocytes in vitro and in vivo. However, the exact mechanism of this process remains unknown. In this study, we investigated the role of the mitogen-activated protein kinase (MAPK) cell-signaling pathway in the differentiation of mBMMSCs into hepatocytes. mBMMSCs were isolated from femurs and tibias, and hepatic differentiation was induced in Isove's modified Eagle's medium supplemented with 10% fetal bovine serum, containing human growth factor and fibroblast growth factor 4. After seven days of induction, morphological characteristics were examined. For inhibition of signaling molecular activities, the inhibitors p38 (SB203580), ERK1/2 (U0126), and MSK1 (H89) were added to the differentiation medium. Real-time polymerase chain reaction and Western blot analysis were used to evaluate the gene expression profiles and protein expression of several markers, including the early specific markers of hepatocytes (AFP and FOXa2), phosphorylated-p38 (p-p38), phosphorylated-ERK1/2 (p-ERK1/2), and phosphorylated- MSK1 (p-MSK1). Expressions of p-p38, p-ERK1/2, and p-MSK1 were effectively inhibited by their respective inhibitors. Expressions of early specific markers, AFP and FOXa2, in the p38, ERK1/2, and MSK1 inhibitor-treated groups were significantly decreased compared to those of the cytokine-induced control. Notably, the expressions of AFP and FOXa2 in the p38 inhibitor group were more obviously reduced than those in the ERK1/2 inhibitor group. The MAPK signaling pathway, especially p38, is sufficient to drive differentiation of mBMMSCs into hepatocytes. This could increase the efficiency of hepatocyte differentiation, which would benefit clinical applications.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Factor 4 de Crecimiento de Fibroblastos/farmacología , Hepatocitos/citología , Sistema de Señalización de MAP Quinasas , Células Madre Mesenquimatosas/citología , Animales , Factor Nuclear 3-beta del Hepatocito/genética , Factor Nuclear 3-beta del Hepatocito/metabolismo , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Humanos , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Ratones , Ratones Endogámicos ICR , Receptores de Péptidos/genética , Receptores de Péptidos/metabolismo , alfa-Fetoproteínas/genética , alfa-Fetoproteínas/metabolismo
12.
Genet Mol Res ; 13(1): 2231-9, 2014 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-24737471

RESUMEN

Our previous studies have indicated that mouse bone marrow mesenchymal stem cells (mBMMSCs) have potential to differentiate into hepatocytes with high efficiency. Our study aimed to evaluate the role of the mouse histone methyltransferase enhancer of zeste homolog 2 gene (EZH2) in the hepatocellular differentiation of mBMMSCs. The mBMMSCs isolated from femurs and tibias were cultured in Iscove's modified Eagle's medium (IMEM) supplemented with 10% fetal bovine serum. Hepatocellular differentiation was induced by 20 ng/mL hepatocyte growth factor and 10 ng/mL fibroblast growth factor 4. The mouse histone methyltransferase EZH2 gene was introduced via PLenti-eGFP-EZH2 or PLenti-eGFP-NEO as a control. Hepatocellular-induced mBMMSCs showed lower expression of EZH2 and lower level of histone H3 lysine 27 trimethylation (H3K27me3) in the AFP and FOXa2 gene promoter regions compared to uninduced mBMMSCs. Introduction of EZH2 inhibited hepatocellular induction, reduced both the mRNA and protein levels of AFP and FOXa2, and increased the level of histone H3K27me3 in the AFP and FOXa2 gene promoter regions. In summary, the mouse histone methyltransferase EZH2 gene could suppress hepatocellular differentiation of mBMMSCs by increasing the level of H3K27me3 in the AFP and FOXa2 gene promoter regions.


Asunto(s)
Diferenciación Celular/genética , Hepatocitos/citología , Hepatocitos/metabolismo , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Complejo Represivo Polycomb 2/genética , Animales , Proteína Potenciadora del Homólogo Zeste 2 , Regulación de la Expresión Génica , Vectores Genéticos/genética , Factor Nuclear 3-beta del Hepatocito/genética , Histonas/metabolismo , Lentivirus/genética , Masculino , Ratones , Complejo Represivo Polycomb 2/metabolismo , Regiones Promotoras Genéticas , Transducción Genética , alfa-Fetoproteínas/genética
13.
Climacteric ; 14(4): 472-81, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21469973

RESUMEN

OBJECTIVES: Drospirenone is a novel progestogen that, combined with 17ß-estradiol, reduces the frequency and severity of menopausal vasomotor symptoms (VMS) in different populations. This double-blind, multicenter study compared the efficacy, safety and tolerability of 2 mg drospirenone/1 mg estradiol (DRSP/E2) vs. placebo in Chinese postmenopausal women with moderate to severe VMS. METHODS: Women, aged 45-65 years, were randomized to DRSP/E2 (n=183) or placebo (n=61) once daily for four 28-day cycles. Changes in the frequency and severity of hot flushes were analyzed as primary variables, together with other climacteric and urogenital symptoms, clinical global improvement, adverse events and physical/gynecological parameters. RESULTS: Relative changes in numbers of hot flushes/week were -80.4% for DRSP/E2 vs. -51.9% for placebo (treatment difference -28.5%, p<0.0001). There were trends toward a greater reduction in severity of hot flushes with DRSP/E2 treatment. Patients treated with DRSP/E2 were more often free from sweating episodes (p<0.0001) and vaginal dryness (p=0.0008). Other climacteric symptoms, including nervousness and pollakisuria, followed a trend of greater response with DRSP/E2. Similar to other combination HRT regimens, DRSP/E2 increased occurrences of bleeding, but these decreased over time. Adverse events in patients treated with DRSP/E2 were mostly mild to moderate and withdrawal rates were low. CONCLUSIONS: Daily treatment of postmenopausal Chinese women with DRSP/E2 for 16 weeks significantly reduced the incidence of hot flushes and demonstrated advantages vs. placebo for other climacteric symptoms. These results indicate that DRSP/E2 is effective, safe and well tolerated in postmenopausal Chinese women.


Asunto(s)
Androstenos/administración & dosificación , Estradiol/administración & dosificación , Terapia de Reemplazo de Estrógeno/métodos , Posmenopausia , Anciano , China , Método Doble Ciego , Combinación de Medicamentos , Femenino , Sofocos/tratamiento farmacológico , Humanos , Persona de Mediana Edad , Antagonistas de Receptores de Mineralocorticoides/administración & dosificación , Placebos , Enfermedades Vaginales/tratamiento farmacológico
14.
Science ; 373(6553): 425-430, 2021 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-34261813

RESUMEN

The Crab Nebula is a bright source of gamma rays powered by the Crab Pulsar's rotational energy through the formation and termination of a relativistic electron-positron wind. We report the detection of gamma rays from this source with energies from 5 × 10-4 to 1.1 peta-electron volts with a spectrum showing gradual steepening over three energy decades. The ultrahigh-energy photons imply the presence of a peta-electron volt electron accelerator (a pevatron) in the nebula, with an acceleration rate exceeding 15% of the theoretical limit. We constrain the pevatron's size between 0.025 and 0.1 parsecs and the magnetic field to ≈110 microgauss. The production rate of peta-electron volt electrons, 2.5 × 1036 ergs per second, constitutes 0.5% of the pulsar spin-down luminosity, although we cannot exclude a contribution of peta-electron volt protons to the production of the highest-energy gamma rays.

15.
Cytotherapy ; 10(7): 668-75, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18985473

RESUMEN

BACKGROUND: Although different strategies have been established for hepatic differentiation of mesenchymal stromal cells (MSC), further studies are required to define an efficient strategy to produce hepatocytes from stem cells and uncover the mechanisms of hepatic differentiation. METHODS: Bone marrow mesenchymal stromal cells (BMMSC), isolated from ICR mice, were induced by fetal liver-conditioned medium from different developmental stages, embryonic days (ED) 9.5, 11.5 and 13.5 and newborn (1 day). Differentiated cells were characterized by morphologic changes, liver-specific gene expression at mRNA and/or protein levels and in vitro functional features. RESULTS: BMMSC morphologically became epithelioid and binucleated after 7 days' exposure to fetal liver-conditioned medium from ED13.5, expressed liver-specific genes (AFP, HNF-3beta, TTR, CK18, ALB and CK19) at mRNA and/or protein levels and acquired in vitro functions characteristic of liver cells, including glycogen storage, urea production and albumin secretion. Conditioned medium derived from fetal liver at ED13.5 was most efficient on hepatic differentiation of BMMSC compared from the other three developmental stages. DISCUSSION: The present study not only provides a high-performance strategy for hepatic differentiation from BMMSC, but also implies liver at different developmental stages might secrete different types of cytokines that have diverse effects on hepatic differentiation, which could support further investigation to provide insight into fundamental processes that govern development and regeneration of the liver.


Asunto(s)
Técnicas de Cultivo de Célula , Transdiferenciación Celular , Medios de Cultivo Condicionados/farmacología , Hepatocitos/citología , Hígado/citología , Células Madre Mesenquimatosas/citología , Albúminas/biosíntesis , Animales , Células de la Médula Ósea/citología , Células de la Médula Ósea/efectos de los fármacos , Feto , Expresión Génica/efectos de los fármacos , Hepatocitos/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/embriología , Masculino , Células Madre Mesenquimatosas/efectos de los fármacos , Ratones , Células del Estroma/citología , Células del Estroma/efectos de los fármacos
16.
Int J Gynecol Cancer ; 18(6): 1258-61, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18217966

RESUMEN

Human ovarian cancer models were established in nude mice by transplanting SKOV(3) cells, and then tumors were exposed to high-intensity electric pulses with a voltage 1000 V, frequency of 1000 Hz, and duration of 250 ns for 1 min. Mitochondria permeability transition pore (PTP) was inspected by cofocal microscope; cytochrome C (Cyt C) and apoptosis-induced factor (AIF) were determined by immunohistochemistry; and voltage-dependent anion channel (VDAC) was measured by immunofluorescence. High-intensity electric pulses exposure led to increases of PTP, Cyt C, and AIF and a decrease of VDAC. These findings revealed that high-intensity electric pulses activated mitochondria electroporation, apoptosis was realized via mitochondria pathway.


Asunto(s)
Apoptosis , Mitocondrias/patología , Neoplasias Ováricas/patología , Animales , Factor Inductor de la Apoptosis/metabolismo , Línea Celular Tumoral , Citocromos c/metabolismo , Electroporación , Femenino , Humanos , Ratones , Ratones Desnudos , Mitocondrias/metabolismo , Membranas Mitocondriales , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/terapia , Permeabilidad , Canales Aniónicos Dependientes del Voltaje/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
17.
Zhonghua Liu Xing Bing Xue Za Zhi ; 37(5): 597-9, 2016 May.
Artículo en Zh | MEDLINE | ID: mdl-27188345

RESUMEN

OBJECTIVE: To evaluate the performance of Zika virus(ZIKV)disease prevention and control. METHODS: Descriptive epidemiological analysis was conducted on the clinical manifestations, laboratory detection results and disease progression of the third imported ZIKV disease case in the mainland of China. RESULTS: On 19 February 2016, a ZIKV disease case was confirmed in Yiwu, Zhejiang province, which was the third imported case of ZIKV disease confirmed by China CDC laboratory and expert consulting. The patient just had a travel to Fiji and Samoa and had mosquito bite history in Samoa. The patient was hospitalized on 16 February after the onset on 14 February and the eruption on 15 February. The body temperature of the patient became normal on 17 February, the rash disappeared on 19 February and the conjunctivitis resolved on 20 February. The positive detection of the viral nucleic acid in blood was only for 3 consecutive days, and the viral nucleic acid could be detected in urine even after negative detection in blood for 4 days. CONCLUSION: The symptoms of the patient were typical. ZIKV can be detected by using blood sample in early phase, but after body temperature become normal, the virus can be detected in urine.


Asunto(s)
ARN Viral/sangre , Viaje , Infección por el Virus Zika/diagnóstico , Virus Zika/aislamiento & purificación , China , Progresión de la Enfermedad , Fiji , Humanos , Laboratorios , Derivación y Consulta , Samoa , Pruebas Serológicas , Encuestas y Cuestionarios , Infección por el Virus Zika/sangre , Infección por el Virus Zika/virología
18.
Zhonghua Nei Ke Za Zhi ; 32(2): 97-9, 1993 Feb.
Artículo en Zh | MEDLINE | ID: mdl-8404333

RESUMEN

The activity of tumor necrosis factor (TNF) in serum and in peripheral blood monocytes (PBMC) was determined in 8 patients with fulminating viral hepatitis (FVH), 10 patients with chronic active hepatitis (CAH) and 10 health controls. The activity was monitored in FVH patients before and after treatment with hepatocyte growth factor (HGF). It was found that TNF level was significantly higher in CAH patients than in controls (t = 3.56, P < 0.01) and also significantly higher in FVH than in CAH patients (t = 3.07, P < 0.01). The activity of TNF decreased gradually in FVH patients after HGF treatment and there was a positive correlation (r = 0.09, P < 0.01) between the activity of serum and PBMC TNF. It was found that in animal models of hepatic necrosis there was transient elevation of TNF activity with its peak occurring after 6 hours; the peak could be lowered with HGF treatment (t = 3.65, P < 0.05). The authors are of the opinion that TNF is an important mediator causing hepatic necrosis. The relationship between HGF and TNF was also discussed.


Asunto(s)
Hepatitis Crónica/sangre , Hepatitis Viral Humana/sangre , Factor de Crecimiento de Hepatocito/uso terapéutico , Factor de Necrosis Tumoral alfa/metabolismo , Adulto , Anciano , Animales , Femenino , Hepatitis Viral Humana/terapia , Humanos , Hígado/patología , Masculino , Persona de Mediana Edad , Necrosis , Ratas , Ratas Wistar
19.
Zhonghua Nei Ke Za Zhi ; 30(10): 637-9, 659, 1992 Oct.
Artículo en Zh | MEDLINE | ID: mdl-1533836

RESUMEN

Combined treatment of thymosin, amino acid, blood products and glucagon-insulin (G-I) for severe viral hepatitis reduced the death rate to 42.11-54.54% in the years from 1983 to 1985. Since 1986, 207 patients with severe viral hepatitis have been treated in our department, 80 of them died (38.6%). All of the patients were divided into 6 groups receiving different therapeutic measures. Group 1 and 2 received different combinations of the above-mentioned drugs; group 3,4,5 and 6 were given fetal liver cell suspension, hepatocyte growth factor (HGF), Chinese traditional medicine and prostaglandin E1 (PGE1) either alone or in combination with other medications. Therapeutic results were better in group 3,4,5 and 6 than in group 1 and 2. Determination of the activity of tumor necrosis factor (TNF) showed that it was higher in the patients than in the control subjects. TNF activity was increased in rats with experimental liver failure; HGF and PGE1 can protect experimental liver necrosis and reduce the serum TNF activity.


Asunto(s)
Hepatitis B/terapia , Hepatitis C/terapia , Adolescente , Adulto , Anciano , Alprostadil/uso terapéutico , Terapia Combinada , Medicamentos Herbarios Chinos/uso terapéutico , Femenino , Sustancias de Crecimiento/uso terapéutico , Hepatitis B/mortalidad , Hepatitis C/mortalidad , Factor de Crecimiento de Hepatocito , Humanos , Masculino , Persona de Mediana Edad , Sobreinfección , Factor de Necrosis Tumoral alfa/análisis
20.
J Tradit Chin Med ; 9(2): 135-9, 1989 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2779277

RESUMEN

Effects of digital acupressure on the blood flow in the capillary arterioles of the cerebral pia mater covering the posterior sigmoidal gyrus in domestic dog (Canis familiaris) were observed. The speed of blood flow was found increased to 185% after continuous digital acupressure for 20 minutes. The increase was most prominent 15 minutes after the acupressure was completed; the effect subsided in 30 minutes. It was also found that in cases of low basal speed of flow before digital acupressure, the increase in the speed of blood flow after acupressure was more pronounced.


Asunto(s)
Terapia por Acupuntura , Piamadre/irrigación sanguínea , Terapia por Acupuntura/métodos , Animales , Velocidad del Flujo Sanguíneo , Capilares/fisiología , Perros , Femenino , Dedos , Masculino , Flujo Sanguíneo Regional
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