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1.
Zhonghua Yi Xue Za Zhi ; 103(12): 913-919, 2023 Mar 28.
Artículo en Chino | MEDLINE | ID: mdl-36973219

RESUMEN

Objective: To investigate the etiology, prevention and treatment status, and their corresponding regional differences of the patients with liver cirrhosis in China, in order to provide scientific basis for the development of diagnosis and control strategies in China. Methods: Clinical data of patients diagnosed with liver cirrhosis for the first time through January 1, 2018 to December 31, 2020 from 50 hospitals in seven different regions of China were collected and analyzed retrospectively, and the difference of etiology, treatment, and their differences in various regions were analyzed. Results: A total of 11 861 cases with liver cirrhosis were included in the study. Thereinto, 5 093 cases (42.94%) were diagnosed as compensated cirrhosis, and 6 768 cases (57.06%) had decompensated cirrhosis. Notably, 8 439 cases (71.15%) were determined as chronic hepatitis B-caused cirrhosis, 1 337 cases (11.27%) were alcoholic liver disease, 963 cases (8.12%) were chronic hepatitis C, 698 cases (5.88%) were autoimmune liver disease, 367 cases (3.09%) were schistosomiasis, 177 cases (1.49%) were nonalcoholic fatty liver, and 743 cases (6.26%) of other types of liver disease. There were significant differences in the incidence of chronic hepatitis B, chronic hepatitis C, alcoholic liver disease, fatty liver, schistosomiasis liver disease, and autoimmune liver disease among the seven regions (P<0.001). Only 1 139 cases (9.60%) underwent endoscopic therapy, thereinto, 718 cases (6.05%) underwent surgical therapy, and 456 cases (3.84%) underwent interventional therapy treatment. In patients with compensated liver cirrhosis, 60 cases (0.51%) underwent non-selective ß receptor blockers(NSBB), including 59 cases (0.50%) underwent propranolol and 1 case (0.01%) underwent carvedilol treatment. In patients with decompensated liver cirrhosis, 310 cases (2.61%) underwent NSBB treatment, including 303 cases (2.55%) underwent propranolol treatment and 7 cases (0.06%) underwent carvedilol treatment. Interestingly, there were significant differences in receiving endoscopic therapy, interventional therapy, NSBB therapy, splenectomy and other surgical treatments among the seven regions (P<0.001). Conclusion: Currently, chronic hepatitis B is the main cause (71.15%) of liver cirrhosis in several regions of China, and alcoholic liver disease has become the second cause (11.27%) of liver cirrhosis in China. The three-level prevention and control of cirrhosis in China should be further strengthened.


Asunto(s)
Hepatitis B Crónica , Hepatitis C Crónica , Hepatopatías Alcohólicas , Humanos , Hepatitis B Crónica/complicaciones , Propranolol/uso terapéutico , Carvedilol/uso terapéutico , Estudios Retrospectivos , Cirrosis Hepática/etiología , Hepatopatías Alcohólicas/complicaciones , Hepatitis C Crónica/complicaciones
2.
J Helminthol ; 97: e19, 2023 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-36755378

RESUMEN

Paravulvus zhongshanensis sp. nov., isolated from soil in a location at Jiangsu Province, China, is described and illustrated based on morphological, morphometric and molecular characterizations. The new species is characterized by its body 1.17-1.53 mm long, lip region offset by marked constriction and 12.1-13.8 µm broad, mural tooth deltoid and 9.6-11.7 µm long, neck 278-360 µm long, pharyngeal expansion 164-208 µm long or occupying more than one-half (54-62%) of total neck length, uterus 32.5-35.3 µm long or 1.0-1.1 times the corresponding body diameter, V = 47.8-53.4, paravulvae absent, female tail subcylindrical conoid (30.5-39.5 µm, c = 36.0-45.5, c' = 1.7-2.2) with widely rounded end, and male unknown. The new species was compared with six known species of the genus including Paravulvus acuticaudatus, Paravulvus confusus, Paravulvus hartingii, Paravulvus iranicus, Paravulvus loofi and Paravulvus microdontus mainly by similarities in having conical tail and c' value larger than 1.3. The rRNA and mitochondrial cytochrome oxidase subunit 1 genes of the new species were obtained and were used for reconstructing the phylogenetic relationships of the new species.


Asunto(s)
Helmintos , Nematodos , Animales , Masculino , Femenino , Filogenia , Helmintos/genética , ARN Ribosómico , China
3.
Zhonghua Gan Zang Bing Za Zhi ; 31(12): 1297-1305, 2023 Dec 20.
Artículo en Chino | MEDLINE | ID: mdl-38253074

RESUMEN

Objective: To investigate the hepatitis B surface antigen (HBsAg) clearance condition and its predictive factors after treatment with nucleos(t)ide analogues to pegylated interferon-α add-on therapy in patients with chronic hepatitis B. Methods: Patients with chronic hepatitis B who visited the First Affiliated Hospital of Zhengzhou University from 2018~2019 were prospectively enrolled. HBsAg≤ 1500 IU/mL, hepatitis B e antigen-negative, HBV DNA undetectable, received antiviral treatment with nucleos(t)ide analogues for at least one year, and pegylated interferon-α add-on therapy for 48 weeks were included. The primary endpoint of study was to determine the proportion of HBsAg clearance at 72 weeks. Concurrently, the predictive factors for HBsAg clearance were analyzed. Quantitative and qualitative data were analyzed using a t-test or non-parametric test and a Fisher's exact test. Results: A total of 38 cases were included in this study, of which 13 cases obtained HBsAg clearance at 48 weeks of therapy and another six cases obtained HBsAg clearance throughout the extended treatment period of 72 weeks, accounting for 50.00% of all enrolled patients. There was a significant difference in HBsAg dynamics between the HBsAg clearance group and the non-clearance group (P < 0.05). Univariate logistic regression analysis showed that patients' age, baseline, 12-and 24-week HBsAg levels, and early HBsAg reduction were predictive factors for HBsAg clearance at 72 weeks of treatment. Multivariate logistic regression analysis showed that age (OR = 1.311; P = 0.016; 95% confidence interval: 1.051~1.635) and HBsAg levels at 24 weeks of treatment (OR = 4.481; P = 0.004; 95% confidence interval: 1.634~12.290) were independent predictors for HBsAg clearance. Conclusion: Hepatitis B e antigen-negative, nucleos(t)ide analogue treated, HBsAg ≤ 1500 IU/mL, and HBV DNA undetectable, peg-IFNα add-on treatment for 48 weeks could promote HBsAg clearance in patients with chronic hepatitis B. Six of the sixteen cases (37.50%) who did not obtain HBsAg clearance at week 48 did so with the course of therapy extended to week 72. Hence, the optimal individualized treatment strategy should be customized according to the predictors rather than the fixed 48-week course. Age (≤ 38), baseline HBsAg level (≤2.86 log(10)IU/ml), HBsAg level at 24 weeks (≤ 0.92 log(10)IU/ml), and 12-week HBsAg decrease from baseline (≥ 0.67 log(10)IU/ml) indicate that patients are highly likely to obtain HBsAg clearance at the 72 weeks of combination therapy, in which the combined indicator based on HBsAg level ≤0.92 log(10)IU/ml at 24 weeks will identify 85.0% to 100.0% of patients with HBsAg clearance.


Asunto(s)
Hepatitis B Crónica , Interferón-alfa , Polietilenglicoles , Humanos , Lactante , ADN Viral , Antígenos e de la Hepatitis B , Antígenos de Superficie de la Hepatitis B , Hepatitis B Crónica/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Polietilenglicoles/uso terapéutico
4.
Zhonghua Shao Shang Za Zhi ; 36(9): 845-852, 2020 Sep 20.
Artículo en Chino | MEDLINE | ID: mdl-32972070

RESUMEN

Objective: To explore the death risk factors of extremely severe burn patients, establish a death risk nomogram predicting model, and investigate the predictive value for death risk of extremely severe burn patients. Methods: The medical records of 231 extremely severe burn patients (190 males and 41 females, aged 18-60 years) who were admitted to the Institute of Burn Research of the First Affiliated Hospital of Army Medical University from January 2010 to October 2018 and met the inclusion criteria were analyzed retrospectively. According to the final outcome, the patients were divided into survival group of 173 patients and death group of 58 patients. The sex, age, severity of inhalation injury, total burn area, full-thickness burn area, burn index, rehydration coefficient and urine volume coefficient of the first and second 24 h after injury, the first base excess, shock index, and hematocrit (HCT) after admission, whether to have pre-hospital fluid infusion, use of ventilator, and use of continuous renal replacement therapy (CRRT), and abbreviated burn severity index (ABSI ) and Baux score on admission of patients in the two groups were recorded or calculated. According to the use of ventilator, the patients were divided into with ventilator group of 131 patients and without ventilator group of 100 patients, and the death, total burn surface area, burn index, incidence and severity of inhalation injury were recorded. According to the use of CRRT, the patients were divided into with CRRT group of 59 patients and without CRRT group of 172 patients, and the death, total burn surface area, and burn index were recorded. Data were statistically analyzed with t test, chi-square test, and Mann-Whitney U test to screen the death related factors of patients. The indexes with statistically significant differences between survival group and death group were included in the multivariate logistic regression analysis to screen the independent death risk factors of patients, and the death risk nomogram predicting model was constructed based on the results.The Bootstrap method was used to validate the death risk nomogram predicting model internally. The predictive value of the nomogram model for predicting death risk of patients was detected by drawing calibration graph and calculating concordance index, and the death risk scores of 231 patients were acquired according to the death risk nomogram model. The receiver's operating characteristic (ROC) curve was drawn, and the optimal threshold and the sensitivity and specificity of optimal threshold in the ROC curve and the area under the curve were calculated. Results: (1) There were statistically significant differences in burn index, ABSI on admission, severity of inhalation injury, total burn area, full-thickness burn area, rehydration coefficient at the first 24 h after injury, use of ventilator, use of CRRT, and Baux score on admission of patients between the two groups (Z=-7.696, -7.031, χ(2)=18.304, 63.065, 23.300, 13.073, 34.240, 59.586, t=-7.536, P<0.01). (2) There were statistically significant differences in death, incidence and severity of inhalation injury, total burn area, and burn index of patients between with ventilator group and without ventilator group (χ(2)=34.240, 17.394, 25.479, Z=-6.557, -7.049, P<0.01). (3) There were statistically significant differences in death, total burn area, and burn index of patients between with CRRT group and without CRRT group (χ(2)=62.982, Z= -47.421, -6.678, P<0.01). (4) The use of ventilator, use of CRRT, and burn index were independent risk factors for the death of extremely severe burn patients (odds ratio=3.277, 5.587, 1.067, 95% confidence interval=1.073-10.008, 2.384-13.093, 1.038-1.096, P<0.05 or P<0.01). (5) The initial concordance index of nomogram predicting model was 0.90 and the corrected concordance index was 0.89. The concordance indexes before and after correction were higher and similar, which showed that the nomogram had good concordance and predictive effect. The optimum threshold of ROC curve was 0.23, the sensitivity and specificity of optimum threshold were 86.0% and 80.0%, respectively, and the area under ROC curve was 0.90 (95% confidence interval=0.86-0.94, P<0.01). Conclusions: Severe burns and damage and/or failure of organ are the main death causes of extremely severe burn patients. The death risk nomogram predicting model established on the basis of use of ventilator, use of CRRT, and burn index have good predictive ability for death of extremely severe burn patients.


Asunto(s)
Quemaduras , Adolescente , Adulto , Femenino , Fluidoterapia , Humanos , Masculino , Persona de Mediana Edad , Nomogramas , Pronóstico , Curva ROC , Estudios Retrospectivos , Choque , Adulto Joven
6.
Zhonghua Shao Shang Za Zhi ; 34(1): 29-31, 2018 Jan 20.
Artículo en Chino | MEDLINE | ID: mdl-29374924

RESUMEN

Fluid therapy is a crucial treatment for patients with extensive burn, which affects patients'prognosis directly. Accurate urine output measurement plays an irreplaceable role in guiding fluid resuscitation in clinic. As one of the best indexes in traditional burn resuscitation, urine output comprehensively reflects systemic circulation. However, it doesn't fully reflect all the specific chapters of microcirculation and systemic circulation and deficient cellular oxygen metabolism exactly. We need to use urine output combined with other shock parameters to ensure adequate fluid replacement. Currently, the most common way of urine output monitoring is manual measurement. The article reviews the application of urine output monitoring in guiding fluid resuscitation of burn shock.


Asunto(s)
Quemaduras/terapia , Fluidoterapia , Resucitación/métodos , Choque/prevención & control , Humanos , Microcirculación , Oxígeno , Choque/terapia
8.
Zhonghua Yi Xue Za Zhi ; 97(40): 3166-3170, 2017 Oct 31.
Artículo en Chino | MEDLINE | ID: mdl-29081164

RESUMEN

Objective: To investigate the prevalence and clinical characteristics of peripheral blood eosinophilia (EOS) in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Methods: From July 2014 to June 2016, AECOPD patients in the Department of Respiratory Medicine of Affiliated Hospital of Chengdu University, were retrospectively stratified into two groups according to two standards of eosinophilic exacerbations (the peripheral blood eosinophil count ≥2% or ≥3% on admission). Demography, clinical symptoms, laboratory results, length of stay, total hospitalization expenses, and defined daily expenses were compared between groups. Results: A total of 559 cases with AECOPD were finally recorded, the prevalence of eosinophilia was 43.1% (241 cases by EOS≥2%) and 27.2% (152 cases by EOS≥3%), respectively. According to either standard, there were no significant differences in sexes, age, course of disease (P>0.05), and there were no significant differences in global initiative for chronic obstructive lung disease (GOLD) grades, parameters of pulmonary function, modified british medical research council (mMRC) scores, rate of antibiotic use, systemic glucocorticoids administration, and average daily expenses (P>0.05). According to 2% standard, leucocytes, neutrophils, monocytes, hs-CRP were lower than non-eosinophilic patients [(5.9±2.0)×10(9)/L vs (8.2±4.0)×10(9)/L, (3.9±1.6)×10(9)/L vs (6.5±3.8)×10(9)/L, (0.446±0.169)×10(9)/L vs (0.501±0.276)×10(9)/L, (25.8±35.9) vs (46.2±55.6) mg/L, all P<0.01]; basophils, lymphocytes were higher than non-eosinophilic patients [(0.043±0.025)×10(9)/L vs (0.029±0.021) ×10(9)/L, (1.3±0.6) ×10(9)/L vs (1.1±0.6) ×10(9)/L, both P<0.01]; length of stay, total hospital expense were shorter (or lower) than non-eosinophilic patients [(10.6±5.0) vs (11.6±5.8) d, (11 851±7 491) vs (14 254±10 751) RMB, both P<0.05]. According to 3% standard, leucocytes, neutrophils, monocytes, hs-CRP were lower than non-eosinophilic patients (all P<0.05), and basophil were higher than non-eosinophilic patients (P<0.01), but no significant differences were observed in lymphocytes, length of stay and total hospital expense (all P>0.05). Conclusion: Eosinophilia is of relative high prevalence in AECOPD patients, and basophil in eosinophilic patients is higher than non-eosinophilic patients.


Asunto(s)
Eosinofilia/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Enfermedad Aguda , Progresión de la Enfermedad , Humanos , Recuento de Leucocitos , Prevalencia
10.
Zhonghua Gan Zang Bing Za Zhi ; 24(11): 834-839, 2016 Nov 20.
Artículo en Chino | MEDLINE | ID: mdl-27978929

RESUMEN

Objective: To investigate the clinical effect of polyvinyl alcohol (PVA) particles combined with chemoembolization using chemotherapeutic agents or chemotherapeutic agents lipiodol emulsion (CALE) in the treatment of hepatocellular carcinoma (HCC) complicated by hepatic arteriovenous shunt (HAVS) and related prognostic factors. Methods: A retrospective analysis was performed for the clinical data of 133 patients with HCC complicated by HAVS. HAVS was classified into slow-flow HAVS, intermediate-flow HAVS, and high-flow HAVS, which were treated with 300-500µm, 500-710µm, and 710-1000µm PVA particles, respectively. The patients with slow-flow and intermediate-flow HAVS underwent embolization with PVA combined with chemotherapeutic agents followed by CALE, while those with high-flow HAVS underwent the treatment with PVA combined with chemotherapeutic agents alone. The survival time, progression-free survival time, and postoperative complications were followed up and analyzed. The Kaplan-Meier method was used to calculate cumulative survival rate and the Cox proportional hazards model was used to determine prognostic factors. Results: The median overall survival (OS) of 133 patients was 9.1 months, and the 6-, 12-, and 24-month survival rates were 73.7%, 36.2%, and 10.2%, respectively. The median OS of slow-flow group (36 patients), intermediate-flow group (58 patients), and high-flow group (39 patients) were 7.3, 9.1, and 10.8 months, respectively. And the 6- and 12-month survival rates were 69.2%/19.0%, 72.4%/39.2%, and 77.8%/42.7%, respectively. There was no significant difference in survival time between the patients with different types of HAVS (χ2= 2.865,P= 0.239). The incidence rates of postoperative gastroesophageal variceal bleeding and acute liver failure were 1.1% and 0.4%, respectively. The results of Cox regression analysis showed that preoperative alpha-fetoprotein level≥400 ng/ml (HR= 2.105,P= 0.006) was an independent risk factor, while multiple embolizations (HR= 0.482,P= 0.011), tumor remission (HR= 0.431,P= 0.041), and multimodality therapy (HR= 0.416,P= 0.004) were independent protective factors. Conclusion: PVA particles combined with chemotherapeutic agents or CALE is safe and effective in the treatment of HCC complicated by HAVS. Patients with multiple embolizations, tumor remission, and multimodality therapy tend to have good prognosis, while those with a high level of alpha-fetoprotein before embolization often have poor prognosis.


Asunto(s)
Derivación Arteriovenosa Quirúrgica , Carcinoma Hepatocelular/terapia , Quimioembolización Terapéutica , Neoplasias Hepáticas/terapia , Alcohol Polivinílico/efectos adversos , Fístula Arteriovenosa , Carcinoma Hepatocelular/patología , Terapia Combinada , Várices Esofágicas y Gástricas/complicaciones , Várices Esofágicas y Gástricas/epidemiología , Aceite Etiodizado , Femenino , Hemorragia Gastrointestinal/complicaciones , Hemorragia Gastrointestinal/epidemiología , Humanos , Incidencia , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento , alfa-Fetoproteínas
11.
Zhonghua Xin Xue Guan Bing Za Zhi ; 44(8): 691-5, 2016 Aug 24.
Artículo en Chino | MEDLINE | ID: mdl-27545128

RESUMEN

OBJECTIVE: To evaluate the efficacy of simultaneous thoracic endovascular aortic repair (TEVAR) and endovascular aneurysm repair (EVAR) on abdominal aortic aneurysm (AAA) patients complicating acute aortic syndrome (AAS). METHODS: Data of 17 patients (16 men, mean age (65.2±6.9) years old) , who underwent simultaneous TEVAR and EVAR between September 2010 and June 2015 in Beijing Anzhen Hospital, were retrospectively reviewed.All patients were diagnosed with concomitant AAA and AAS by preoperative CTA.All abdominal aortic lesions were AAA and all thoracic aortic lesions were AAS.Under local anesthesia, simultaneous TEVAR and EVAR were performed and emergent simultaneous endovascular repair was performed in 2 patients.Follow up was made at 1 month, 3 months, 6 months, and yearly after the procedure.Procedure success rate, procedure related complications were evaluated. RESULTS: Procedure was successful in all patients.The length of thoracic coverage was (21.0±4.6) cm.The operation time was 150(120, 170) min, and the hospitalization time was 7 (6, 12) d. After a mean of 27.0(5.5, 44.5) months follow up, there were no acute cardiopulmonary complications and contrast induced nephropathy.One patient developed spinal cord ischemia and resolved after treatment.One patient was died for aneurysm rupture at 6 months post operation.One patient developed type Ⅰb endoleak for expansion of right iliac artery at 9 months post operation and was successfully sealed by iliac stent-graft extension. CONCLUSIONS: Combined TEVAR and EVAR can be performed successfully in patients with AAA complicating AAS.When anatomically feasible, simultaneous TEVAR and EVAR can be considered as a effective and safe therapy alternative to patients with multilevel aortic diseases.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Procedimientos Endovasculares , Anciano , Aorta Abdominal/cirugía , Aorta Torácica/cirugía , Implantación de Prótesis Vascular , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Stents , Factores de Tiempo , Resultado del Tratamiento
14.
Water Sci Technol ; 63(1): 51-6, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21245553

RESUMEN

Laboratory-scale experiments were conducted to investigate the removal and fate of estrogens 17ß-estradiol (E2) and 17α-ethinylestradiol (EE2) in an anaerobic-anoxic-oxic (AAO) activated sludge system. Estrogen concentrations in the aqueous and solid phases in each reactor of AAO system were analyzed separately. E2 was not detected in the final effluent. The anaerobic, anoxic and oxic reactors accounted for 71%, 7% and 22% of the overall E2 removal, respectively. The overall EE2 removal efficiency was about 80%, and the anaerobic, anoxic and oxic reactors were responsible for 44%, 8% and 48% of the overall EE2 removal, respectively. In anaerobic unit, sorption was the dominant mechanism for the removal of E2 and EE2. While E2 was degraded in all the three units of the AAO system, EE2 was only degraded in the anoxic and aerobic units. Biodegradation is important for the fate of E2 compared to sorption. Of the total influent E2 in the AAO system, 99.99% was biodegraded and 0.01% remained in the waste sludge. Nevertheless, both sorption and biodegradation play important roles in the removal of EE2. Of the total influent EE2, 79.1% was degraded by activated sludge, 19.9% was discharged in the effluent and 1% remained in the waste sludge.


Asunto(s)
Estrógenos/aislamiento & purificación , Oxígeno/química , Aguas del Alcantarillado , Contaminantes Químicos del Agua/aislamiento & purificación , Anaerobiosis
15.
Amino Acids ; 33(3): 537-41, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17048123

RESUMEN

Optically pure (S)-3-p-hydroxyphenyllactic acid derivatives are important intermediates of peroxisome proliferator-activated receptor alpha/gamma dual agonists and heteropeptides. Many efforts have been made for synthesis of those intermediates, but there exist some flaws yet. We observed that dielectric constants of organic solvents drastically affected diazotization of O-benzyl-L-tyrosine. Optically pure (S)-3-p-benzyloxyphenyllactic acid was obtained by simple recrystallization when DMF or DMSO of higher dielectric constant was used as a co-solvent in diazotization of O-benzyl-L-tyrosine. It was easily turned into various optically pure (S)-3-p-hydroxyphenyllactic acid derivatives.


Asunto(s)
Fenilpropionatos , Conformación Molecular , Fenilpropionatos/síntesis química , Fenilpropionatos/química , Solventes
16.
Amino Acids ; 28(4): 369-72, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15889220

RESUMEN

The reactions of phosphorus trichloride with various amino acids afford the pentacoordinated spirophosphoranes. The reaction procedures were traced by (31)P NMR spectra techniques. A new crystal structure of alanine derivative was characterized, which is a slightly distorted TBP structure. Besides, this kind of spirophosphoranes are potent inhibitors to tyrosinase.


Asunto(s)
Aminoácidos/química , Cloruros/química , Inhibidores Enzimáticos/síntesis química , Fosforanos/síntesis química , Compuestos de Fósforo/química , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Espectroscopía de Resonancia Magnética , Estructura Molecular , Monofenol Monooxigenasa/antagonistas & inhibidores , Fosforanos/química , Fosforanos/farmacología
17.
Bioelectromagnetics ; 25(1): 1-4, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14696047

RESUMEN

The effect of 30.16 GHz millimeter wave (MMW) exposure at 1.0 and 3.5 mW/cm2 on gap junction intercellular communication (GJIC) was studied in cultured HaCaT keratinocytes, using the fluorescence recovery after photobleaching (FRAP) technique and laser confocal scanning microscopy to follow the intracellular movement of 5,6-carboxyfluorescein diacetate dye. While MMW exposure alone for 1 h at either 1.0 or 3.5 mW/cm2 did not affect GJIC, MMW exposure in combination with 5 ng/ml TPA treatment reversed TPA induced suppression of GJIC. Exposure at 1.0 mW/cm2 resulted in a partial reversal, and exposure at 3.5 mW/cm2 resulted in essentially full reversal of the TPA suppression.


Asunto(s)
Comunicación Celular/efectos de los fármacos , Comunicación Celular/efectos de la radiación , Uniones Comunicantes/efectos de los fármacos , Uniones Comunicantes/efectos de la radiación , Queratinocitos/efectos de los fármacos , Queratinocitos/efectos de la radiación , Microondas , Ésteres del Forbol/farmacología , Línea Celular , Relación Dosis-Respuesta en la Radiación , Resistencia a Medicamentos/efectos de la radiación , Recuperación de Fluorescencia tras Fotoblanqueo , Humanos , Microscopía Confocal , Dosis de Radiación
18.
Bioelectromagnetics ; 24(2): 134-8, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12524680

RESUMEN

We have previously demonstrated that exposure of Chinese hamster lung (CHL) cells to 50 Hz magnetic fields (MFs) and/or 12-O-tetradecanoylphorbol-3-acetate (TPA)-inhibited gap junctional intercellular communication (GJIC). To explore and compare the mechanisms of GJIC inhibition induced by extremely low frequency (ELF) MF and TPA, the number and localization of connexin 43 (C x 43) were studied. The localization of C x 43 was determined with indirect immunofluorescence histochemical analysis and detected by confocal microscopy after exposing CHL cells to 50 Hz sinusoidal magnetic field at 0.8 mT for 24 h without or with TPA (5 ng/ml) for the last 1 h. The C x 43 levels in nuclei and in cytoplasm were examined by Western blotting analysis. The results showed that the cells exposed to MF and/or TPA displayed individual plaques at regions of intercellular contact, which were fewer than the normal cells in number, while the number of C x 43 in cytoplasm increased and congregated near the nuclei. Western blot analysis further demonstrated the quantity of changes in location of Cx43. These results suggest that reduction of C x 43 at regions of intercellular contact may be one of the mechanisms of GJIC inhibition induced by ELF MF.


Asunto(s)
Conexina 43/biosíntesis , Campos Electromagnéticos , Pulmón/metabolismo , Pulmón/efectos de la radiación , Acetato de Tetradecanoilforbol/farmacología , Animales , Comunicación Celular/efectos de los fármacos , Comunicación Celular/fisiología , Comunicación Celular/efectos de la radiación , Células Cultivadas , Conexina 43/análisis , Cricetinae , Pulmón/citología , Pulmón/efectos de los fármacos , Microscopía Confocal/métodos
19.
Bioelectromagnetics ; 22(8): 568-73, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11748674

RESUMEN

The effects of extremely low frequency (ELF) magnetic field on gap junctional intercellular communication (GJIC), protein levels, and phosphorylation of connexin43 (Cx43) were studied in NIH3T3 cells. The suppression of GJIC by 24 h, 50 Hz, 0.8 mT ELF magnetic field, 2 h, 3 ng/ml 12-O-tetradecanoylphorbol-13-acetate (TPA), or ELF combined with TPA treatment was confirmed by the fluorescence recovery after photobleaching (FRAP) analysis with a confocal microscope. The results showed that ELF or TPA exposure induced 50-60% inhibition of GJIC (P < 0.01). ELF combined with TPA enhanced the inhibition of GJIC. Western blot analysis using Cx43 specific antibodies showed obviously decreasing non phosphorylated Cx43 (P(0)) induced by ELF and/or TPA exposure. On the other hand, cells treated with ELF and/or TPA displayed a hyperphosphorylated Cx43 band (P(3)). However, there was no obvious changes in the level of Cx43 protein. The results implied that the P(3) band appeared to result from phosphorylation of P(0). But it remains possible that upon the ELF exposure P(0) is converted to P(1), P(2) or both and that P(3) is formed from P(1) or P(2) resulting in the observed hyperphosphorylation pattern. From the present study, we conclude that ELF magnetic field inhibits GJIC and the main mechanism is the hyperphosphorylation of Cx43.


Asunto(s)
Comunicación Celular/fisiología , Conexina 43/metabolismo , Uniones Comunicantes/fisiología , Magnetismo/efectos adversos , Células 3T3 , Animales , Comunicación Celular/efectos de los fármacos , Conexina 43/química , Uniones Comunicantes/efectos de los fármacos , Ratones , Fosforilación , Acetato de Tetradecanoilforbol/farmacología
20.
J Cell Biochem ; 79(3): 460-70, 2000 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-10972983

RESUMEN

Magnetic fields (MFs) of various characteristics can lead to plethora effects in biological system. From a molecular point of view, we hypothesized that there must be a fundamental difference in gene expression between the MF exposed and the unexposed cell. To identify the classes of genes that are regulated, 0.8 mT 50 Hz MF-induced changes in gene expression were examined in a Daudi cell culture using differential display and reverse transcriptase-polymerase chain reaction. A candidate cDNA (signatured as MF-CB) that was observed in the sham-exposed but not in MF-exposed cultures was recovered and reamplified. After verification by Northern blot, the cDNA was cloned and sequenced. It was found that 254-base pair of 5'-end MF-CB cDNA clone was identical to gcs in open reading frame (ORF) range. Based on the preliminarily sequence, the prolonged length of 5'-end MF-CB cDNA was obtained by PCR amplification and its sequence analysis showed the same results as its original fragment. In order to further determine whether MF-CB cDNA is from gcs, two Northern blots were probed with gcs and MF-CB cDNA, respectively, and the data revealed signals of the same size and expression pattern on the two probe filters, which demonstrated that MF-CB is an EST (expression sequence tag) of gcs. gcs is a gene, identified recently (GenBank accession number D89866), encoding ceramide glucosyltransferase (GCS), which has been implicated as a causal element in human cell growth and differentiation. In an additional experiment, time-dependent changes in the transcription of gcs induced by 0.8 mT MF were observed by Northern blot with a sharp and reproducible inhibition effect after 20 min exposure and a reduction after 20-24 h exposure. The study demonstrates for the first time that 50 Hz MF can lead to changes in gcs transcription, which provides a new clue to elucidate the mechanism by which MF influence cell growth and differentiation.


Asunto(s)
Linfoma de Burkitt/patología , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de la radiación , Glucosiltransferasas/genética , Magnetismo , Proteínas de Neoplasias/genética , ARN Mensajero/biosíntesis , ARN Neoplásico/biosíntesis , Técnica de Sustracción , Transcripción Genética/efectos de la radiación , Secuencia de Aminoácidos , Secuencia de Bases , Northern Blotting , Linfoma de Burkitt/genética , Clonación Molecular , ADN Complementario/genética , Inducción Enzimática/efectos de la radiación , Glucosiltransferasas/biosíntesis , Humanos , Datos de Secuencia Molecular , Proteínas de Neoplasias/biosíntesis , Reacción en Cadena de la Polimerasa , Homología de Secuencia de Ácido Nucleico , Células Tumorales Cultivadas/metabolismo , Células Tumorales Cultivadas/efectos de la radiación
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