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Objective: To explore the role of mechanical hemodynamic support (MHS) in mapping and catheter ablation of patients with hemodynamically unstable ventricular tachycardia (VT), report single-center experience in a cohort of consecutive patients receiving VT ablation during MHS therapy, and provide evidence-based medical evidence for clinical practice. Methods: This was a retrospective cohort study. Patients with hemodynamically unstable VT who underwent catheter ablation with MHS at Beijing Anzhen Hospital, Capital Medical University between August 2021 and December 2023 were included. Patients were divided into rescue group and preventive group according to the purpose of treatment. Their demographic data, periprocedural details, and clinical outcomes were collected and analyzed. Results: A total of 15 patients with hemodynamically unstable VT were included (8 patients in the rescue group and 7 patients in the preventive group). The acute procedure was successful in all patients. One patient in the rescue group had surgical left ventricular assist device (LVAD) implantation, remaining 14 patients received extracorporeal membrane oxygenation (ECMO) for circulation support. ECMO decannulation was performed in 12 patients due to clinical and hemodynamic stability, of which 6 patients were decannulation immediately after surgery and the remaining patients were decannulation at 2.0 (2.5) d after surgery. Two patients in the rescue group died during the index admission due to refractory heart failure and cerebral hemorrhage. During a median follow-up of 30 d (1 d to 12 months), one patient with LVAD had one episode of ventricular fibrillation at 6 months after discharge, and no further episodes of ventricular fibrillation and/or VT occurred after treatment with antiarrhythmic drugs. No malignant ventricular arrhythmia occurred in the remaining 12 patients who were followed up. Conclusions: MHS contributes to the successful completion of mapping and catheter ablation in patients with hemodynamically unstable VT, providing desirable hemodynamic status for emergency and elective conditions.
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Ablación por Catéter , Hemodinámica , Taquicardia Ventricular , Humanos , Taquicardia Ventricular/cirugía , Taquicardia Ventricular/fisiopatología , Taquicardia Ventricular/terapia , Estudios Retrospectivos , Ablación por Catéter/métodos , Resultado del Tratamiento , Oxigenación por Membrana Extracorpórea/métodos , Corazón Auxiliar , Masculino , Femenino , Persona de Mediana EdadRESUMEN
Objective: To investigate the timing of pericardial drainage catheter removal and restart of the anticoagulation in patients with atrial fibrillation (AF) suffered from perioperative pericardial tamponade during atrial fibrillation catheter ablation and uninterrupted dabigatran. Methods: A total of 20 patients with pericardial tamponade, who underwent AF catheter ablation with uninterrupted dabigatran in Beijing Anzhen Hospital from January 2019 to August 2021, were included in this retrospective analysis. The clinical characteristics of enrolled patients, information of catheter ablation procedures, pericardial tamponade management, perioperative complications, the timing of pericardial drainage catheter removal and restart of anticoagulation were analyzed. Results: All patients underwent pericardiocentesis and pericardial effusion drainage was successful in all patients. The average drainage volume was (427.8±527.4) ml. Seven cases were treated with idarucizumab, of which 1 patient received surgical repair. The average timing of pericardial drainage catheter removal and restart of anticoagulation in 19 patients without surgical repair was (1.4±0.7) and (0.8±0.4) days, respectively. No new bleeding, embolism and death were reported during hospitalization and within 30 days following hospital discharge. Time of removal of pericardial drainage catheter, restart of anticoagulation and hospital stay were similar between patients treated with idarucizumab or not. Conclusion: It is safe and reasonable to remove pericardial drainage catheter and restart anticoagulation as soon as possible during catheter ablation of atrial fibrillation with uninterrupted dabigatran independent of the idarucizumab use or not in case of confirmed hemostasis.
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Fibrilación Atrial , Taponamiento Cardíaco , Ablación por Catéter , Humanos , Fibrilación Atrial/complicaciones , Fibrilación Atrial/cirugía , Fibrilación Atrial/tratamiento farmacológico , Dabigatrán/uso terapéutico , Taponamiento Cardíaco/terapia , Taponamiento Cardíaco/complicaciones , Anticoagulantes/uso terapéutico , Estudios Retrospectivos , Resultado del Tratamiento , Drenaje/efectos adversos , Catéteres/efectos adversosRESUMEN
Objective: To compare the differences between CAS risk model and CHA2DS2-VASc risk score in predicting all cause death, thromboembolic events, major bleeding events and composite endpoint in patients with nonvalvular atrial fibrillation. Methods: This is a retrospective cohort study. From the China Atrial Fibrillation Registry cohort study, the patients with atrial fibrillation who were>18 years old were randomly divided into CAS risk score group and CHA2DS2-VASc risk score group respectively. According to the anticoagulant status at baseline and follow-up, patients in the 2 groups who complied with the scoring specifications for anticoagulation were selected for inclusion in this study. Baseline information such as age and gender in the two groups were collected and compared. Follow-up was performed periodically to collect information on anticoagulant therapy and endpoints. The endpoints were all-cause death, thromboembolism events and major bleeding, the composite endpoint events were all-cause death and thromboembolism events. The incidence of endpoints in CAS group and CHA2DS2-VASc group was analyzed, and multivariate Cox proportional risk model was used to analyze whether the incidence of the endpoints was statistically different between the two groups. Results: A total of 5 206 patients with AF were enrolled, average aged (63.6±12.2) years, and 2092 (40.2%) women. There were 2 447 cases (47.0%) in CAS risk score group and 2 759 cases (53.0%) in CHA2DS2-VASc risk score group. In the clinical baseline data of the two groups, the proportion of left ventricular ejection fraction<55%, non-paroxysmal atrial fibrillation, oral warfarin and HAS BLED score in the CAS group were lower than those in the CHA2DS2-VASc group, while the proportion of previous diabetes history and history of antiplatelet drugs in the CAS group was higher than that in the CHA2DS2-VASc group, and there was no statistical difference in other baseline data. Patients were followed up for (82.8±40.8) months. In CAS risk score group, 225(9.2%) had all-cause death, 186 (7.6%) had thromboembolic events, 81(3.3%) had major bleeding, and 368 (15.0%) had composite endpoint. In CHA2DS2-VASc risk score group, 261(9.5%) had all-cause death 209(7.6%) had thromboembolic events, 112(4.1%) had major bleeding, and 424 (15.4%) had composite endpoint. There were no significant differences in the occurrence of all-cause death, thromboembolic events, major bleeding and composite endpoint between anticoagulation in CAS risk score group and anticoagulation in CHA2DS2-VASc risk score group (log-rank P =0.643, 0.904, 0.126, 0.599, respectively). Compared with CAS risk score, multivariable Cox proportional hazards regression models showed no significant differences for all-cause death, thromboembolic events, major bleeding and composite endpoint between the two groups with HR(95%CI) 0.95(0.80-1.14), 1.00(0.82-1.22), 0.83(0.62-1.10), 0.96(0.84-1.11), respectively. All P>0.05. Conclusions: There were no significant differences between CAS risk model and CHA2DS2-VASc risk score in predicting all-cause death, thromboembolic events, and major bleeding events in Chinese patients with non-valvular atrial fibrillation.
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Fibrilación Atrial , Accidente Cerebrovascular , Tromboembolia , Adolescente , Anticoagulantes , Fibrilación Atrial/complicaciones , Fibrilación Atrial/tratamiento farmacológico , Estudios de Cohortes , Femenino , Hemorragia/complicaciones , Humanos , Masculino , Estudios Retrospectivos , Medición de Riesgo , Accidente Cerebrovascular/epidemiología , Volumen Sistólico , Tromboembolia/etiología , Función Ventricular IzquierdaRESUMEN
Objective: To explore the relationship between age at menarche and general obesity (based on BMI) and central obesity (based on WC or WHtR) in middle-aged and elderly women in China. Methods: A total of 6 363 women from the China Health and Retirement Longitudinal Study were included. Restricted cubic splines based on binary logistic regressions were used to analyze the relationship between age at menarche and the risk of obesity. Age at menarche was divided into four groups: ≤13, 14- (control group), 16- , and ≥18 years old. Binary logistic regressions were applied to analyze the relationship between the continuous or grouped variable of age at menarche and the risk of obesity. Results: After adjusting potential confounders, the age at menarche showed a negative linear relationship with the risk of general obesity and central obesity. The risk for obesity based on BMI, WC and WHtR significantly decreased by 6% (OR=0.94, 95%CI: 0.90-0.99), 4% (OR=0.96, 95%CI: 0.92-1.00), and 6% (OR=0.94, 95%CI: 0.90-0.99) for each 1 year increase in age at menarche. Compared with participants who had menarche at age 14- years old, the risk for obesity based on BMI (OR=0.71, 95%CI: 0.55-0.91), WC (OR=0.75, 95%CI: 0.62-0.92) and WHtR (OR=0.76, 95%CI: 0.61-0.96) significantly decreased by 29%, 25%, and 24% in participants who had menarche at age ≥18 years old. Conclusions: There was a negative linear relationship between age at menarche and the risk for general obesity and central obesity in middle-aged and elderly women in China. Older age at menarche might be negatively associated with risk for obesity in middle-aged and elderly women.
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Menarquia , Obesidad , Adolescente , Anciano , Índice de Masa Corporal , China/epidemiología , Femenino , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Obesidad/epidemiología , Factores de Riesgo , Circunferencia de la CinturaRESUMEN
Objective: To evaluate the safety and effectiveness of left atrial appendage occlusion (LAAO) in patients with atrial fibrillation and end-stage renal disease undergoing long-term hemodialysis. Methods: Six patients with AF and end-stage renal disease(ESRD)on long term hemodialysis who underwent LAAO from March 2017 to March 2021 in Beijing Anzhen Hospital were enrolled. Baseline characteristics such as age, sex, types of arrhythmia, stroke and bleeding score, and continuous dialysis time were collected. Four patients underwent LAAO, two patients underwent the combined procedure of catheter ablation and LAAO. Perioperative treatment and serious complications were recorded. Transesophageal echocardiography was repeated at 45 days and 60 days after the procedure. Telephone follow-up was conducted at 3, 6 and 12 months after the procedure, and every 6 months thereafter. Thromboembolism and major bleeding events and survival were evaluated. Results: The average age was (66.7±17.0) years old, and 5 were male (5/6). There were 4 patients with paroxysmal AF (4/6), and 2 patients with persistent AF (2/6). The mean CHA2DS2-VASc score was (4.8±1.5), and the HAS-BLED score was (3.5±1.4). The duration of hemodialysis was 2.6 (1.1, 8.3) years. Successfully Watchman implantation was achieved in all patients. There were no severe perioperative complications, and no device related thrombosis or leaks were observed by transesophageal echocardiography. During a mean of 22.0 (12.0, 32.0) months follow-up, there was no thromboembolism or major bleeding events. A total of 2 patients died, one from sudden cardiac death, and another one from heart failure. Conclusions: LAAO may be a safe and effective therapeutic option for prevention of thromboembolism in patients with atrial fibrillation and end-stage renal disease undergoing long-term hemodialysis, further studies with larger patient cohort are needed to confirm our results.
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Apéndice Atrial , Fibrilación Atrial , Fallo Renal Crónico , Accidente Cerebrovascular , Tromboembolia , Anciano , Anciano de 80 o más Años , Apéndice Atrial/diagnóstico por imagen , Apéndice Atrial/cirugía , Fibrilación Atrial/complicaciones , Fibrilación Atrial/cirugía , Ecocardiografía Transesofágica , Humanos , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/terapia , Masculino , Persona de Mediana Edad , Diálisis Renal , Resultado del TratamientoRESUMEN
Objective: To investigate the efficacy and safety of idarucizumab in the treatment of perioperative cardiac tamponade and thromboembolic events during catheter ablation in atrial fibrillation (AF) patients under dabigatran therapy. Methods: This study was a retrospective analysis enrolling patients under dabigatran therapy, who underwent catheter ablation for AF at Beijing Anzhen Hospital from January 2019 to December 2020 and developed perioperative cardiac tamponade or acute ischemic stroke (AIS) and received idarucizumab to reverse the anticoagulant effect of dabigatran. Patients' age, sex, renal function, coagulation test and safety events at 30 d after idarucizumab administration were collected and analyzed. The clinical presentation and prognosis were also analyzed. Results: A total of 7 patients were included, 2 (2/7) were male, mean age was (66.3±11.2) years, serum creatinine level was (66.3±13.6) µmol/L, estimated glomerular filtration rate was (89.4±11.2) ml·min-1·1.73 m-2, CHA2DS2-VASc and HAS-BLED scores were (3.2±1.9) and (1.3±1.3), respectively. Five patients (5/7) developed cardiac tamponade during the perioperative period and the time interval to the last dose of dabigatran was (6.3±2.6) h. Idarucizumab was given at (36.4±16.7) min after the definitive diagnosis of cardiac tamponade. A significant decrease of activated partial thromboplastin time was achieved after idarucizumab administration in all five cases. Pericardial puncture and drainage were applied to all patients (5/5) with cardiac tamponade, the drainage volume was (1 037.0±846.9) ml, the retention time of pericardial drainage catheter was (27.9±13.9) h, and the recovery time of anticoagulation was (28.4±13.2) h. One patient (1/5) underwent thoracotomy for hemostasis due to excessive blood loss with the aim of ensuring complete hemostasis. Bleeding occurred in 1 patient (1/5) after the first restart of anticoagulation. AIS occurred in 2 patients (2/7) after operation. One case (1/2) received intravenous thrombolysis after receiving 5.0 g idarucizumab, no hemorrhagic transformation was observed, and the recovery process was satisfactory. Another patient in this group experienced significantly prolonged onset time and 5.0 g idarucizumab was applied before intravascular thrombectomy, there was no bleeding complication in this patient after thrombectomy. At the time of discharge, the consciousness was not significantly improved, and the muscle strength of the right lower limb was recovered somehow compared with that before operation. No hypersensitivity reactions or thrombotic events occurred in these patients within 30 days of the administration of idarucizumab. Conclusion: In AF catheter ablation-associated cardiac tamponade and AIS, idarucizumab is safe and effective in rapidly reversing the anticoagulant effect of dabigatran, use of thrombectomy saves valuable time for timely hemostasis and improvement of cerebral blood circulation.
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Objective: To investigate the incidence and clinical characteristics of left atrial appendage (LAA) thrombus in patients with hypertrophic cardiomyopathy (HCM) and non-valvular atrial fibrillation (AF) . Methods: Data from 10 440 patients with AF who had undergone transesophageal echocardiography (TEE) before cardioversion or catheter ablation at Beijing Anzhen Hospital from April 2006 to December 2018 were retrospectively screened. Two hundred and five HCM patients were included, 820 AF patients with the same CHA(2)DS(2)-VASc score over the same period were selected as the control group. HCM patients were divided into two subgroups based on presence or absence of LAA thrombus/sludge. The baseline of clinical information, transthoracic echocardiographic and TEE measures were compared among all the groups. Receiver operating characteristic (ROC) curve was used to evaluate the diagnostic value of left atrial diameter (LAD) for LAA thrombus/sludge. Multivariate logistic regression analysis was applied to analyze the correlative factors of LAA thrombus/sludge in HCM patients. Results: The incidences of LAA thrombus or sludge were higher in HCM group than in control group (10.7% (22/205) vs. 0.7% (6/820); 8.8% (18/205) vs.7.0% (57/820), P<0.001) . In HCM patients, LAD was significantly larger in LAA thrombus/sludge subjects than in those without thrombus/sludge ((48.9±5.1)mm vs. (45.2±6.1) mm, P<0.001). CHA(2)DS(2)-VASc score was similar between the two subgroups ((2.0±1.4) vs. (1.8±1.4), P>0.05). There was no difference in the rate of patients with a CHA(2)DS(2)-VASc scores ≥2 between the subgroups(62.5% (25/40) vs. 57.0% (94/165), P=0.525). The incidences of LAA thrombus in HCM and AF patients with CHA(2)DS(2)-VASc scores of 0, 1 and 2 were 8.8% (3/34) , 9.6% (5/52) , 11.8% (11/119) , respectively; and the rate of LAA sludge were 8.8% (3/52) , 7.7% (4/52) , 9.2% (11/119) , respectively. The cut off value of LAD for the diagnosis of LAA thrombus/sludge was 44.5 mm. Multivariate logistic regression analysis showed that LAD≥44.5 mm (OR=5.134, 95%CI 1.862-14.156, P=0.002) , non-paroxysmal AF (OR=2.782, 95%CI 1.238-6.252, P=0.013) , previous thromboembolism or stroke (OR=1.820, 95%CI 0.774-4.227, P=0.017) were independent determinants of LAA thrombus/sludge. Conclusions: The incidence of LAA thrombus/sludge is higher in patients with HCM and AF than in AF patients without HCM. The CHA(2)DS(2)-VASc score is similar between HCM and AF patients with LAA thrombus/sludge and those without thrombus/sludge. Patients with CHA(2)DS(2)-VASc score 0-1 are also likely to suffer LAA thrombus/sludge. Left atrial enlargement is associated with LAA thrombus/sludge.
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Apéndice Atrial , Fibrilación Atrial , Cardiomiopatía Hipertrófica , Trombosis , Ecocardiografía Transesofágica , Humanos , Estudios Retrospectivos , Factores de RiesgoRESUMEN
Objective: To investigate the effect of non-vitamin K antagonist oral anticoagulants (NOAC) on left atrial or atrial appendage (LA/LAA) thrombi in patients with nonvalvular atrial fibrillation (NVAF). Method: Data from 3 042 patients with atrial fibrillation(AF), who underwent transesophageal echocardiography (TEE) examination before cardioversion or catheter ablation for the detection of LA/LAA thrombus in our department from March 2016 to January 2018 were prospectively analyzed. Among these patients, LA/LAA thrombus was detected by TEE in 57 patients. A total of 19 patients who received dabigatran or rivaroxaban for ≥3 weeks and underwent repeated TEE were included, 38 patients were excluded (7 patients with rheumatic heart disease, 1 patient treated with pericardial decortication, 1 patient treated with surgical repair of endocardial cushion defect, 1 patient with LA thrombus associated with the atrial septal occluder device, 14 patients received warfarin therapy, 14 patients did not receive repeated TEE). Results: First repeated TEE results showed that LA/LAA thrombus was not completely resolved in 4 out of 4 patients treated with dabigatran (110 mg bid) for a median time of 119 (47, 258) days, whereas LA/LAA thrombus was completely resolved in 5 out of 11 patients treated with dabigatran (150 mg bid) for a median time of 80 (58, 147) days. Thrombus was completely resolved in 2 out of 2 patients treated with rivaroxaban (15 mg qd) for 110 days and 95 days respectively, and in 1 out of 2 patients treated with rivaroxaban (20 mg qd) for 91 days. Second repeated TEE was performed in 8 patients. Thrombus was resolved completely in 2 out of 3 patients with undissolved thrombus treated by dabigatran (110 mg bid) after increasing the dabigatran dosage (150 mg bid). Thrombus was resolved in 3 (1 patient prolonged treatment with dabigatran 150 mg bid and 2 patients switched to rivaroxaban 20 mg qd) out of 4 patients with undissolved thrombus under the dabigatran 150 mg bid regimen, whereas the thrombus remained unresolved in 1 patient switched to rivaroxaban (15 mg qd). After receiving rivaroxaban 15 mg bid treatment, the thrombus was finally resolved in 1 patient with undissolved thrombus treated by rivaroxaban 20 mg qd. There was no clinical thromboembolism or major bleeding events during the median follow up time of 462 (305, 558) days. Conclusions: Our data show that NOAC is an effective therapeutic option for the treatment of LA/LAA thrombi. When eligible, a higher NOAC dosage may be preferred due to the higher efficacy on thrombus resolvement.
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Apéndice Atrial , Fibrilación Atrial , Inhibidores del Factor Xa , Rivaroxabán , Trombosis , Anticoagulantes/uso terapéutico , Apéndice Atrial/diagnóstico por imagen , Apéndice Atrial/efectos de los fármacos , Fibrilación Atrial/complicaciones , Fibrilación Atrial/tratamiento farmacológico , Ecocardiografía Transesofágica , Inhibidores del Factor Xa/uso terapéutico , Humanos , Rivaroxabán/uso terapéutico , Trombosis/tratamiento farmacológicoRESUMEN
Objective: To investigate right ventricular function in patients with pneumoconiosis, and to provide a basis for quantitative diagnosis and treatment of pneumoconiosis in clinical practice. Methods: A total of 43 patients with pneumoconiosis who were hospitalized consecutively in Shijiazhuang Prevention and Treatment Center for Occupational Diseases from May 2015 to May 2016 were enrolled, and according to the stage of pneumoconiosis, they were divided into stage I group with 16 patients, stage II group with 14 patients, and stage III group with 13 patients. A total of 16 healthy subjects were enrolled as control group. Echocardiography was performed and the relevant parameters were recorded, i.e., right ventricular transverse diameter (RVTD), tricuspid annular plane systolic excursion (TAPSE), and right ventricular myocardial performance index(Tei index). Results: There were significant differences in Tei index and TAPSE between all groups (P <0.05) except between the stage I group and the control group in terms of Tei index (P>0.05) and between the stage I group and the stage II group in terms of TAPSE (P>0.05). Right ventricular Tei index was negatively correlated with TAPSE (r=-0.547,P<0.05). Conclusion: A combination of right ventricular Tei index and TAPSE can be used for early quantitative evaluation of right ventricular function in patients with pneumoconiosis.
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Ecocardiografía/métodos , Válvula Tricúspide/fisiopatología , Función Ventricular Derecha/fisiología , Estudios de Casos y Controles , Humanos , Neumoconiosis , SístoleRESUMEN
Objective: To study the intention on quitting smoking and related factors, so as to provide evidence on related important determinants. Methods: A cross-sectional study was conducted in 14 villages in Shandong, China. A total of 1 287 male daily smokers were interviewed, face-to-face. Multiple logistic regression method was used to assess the factors associated with quitting intention among male daily smokers. Dominance analysis was used to assess the relative contribution of determinants on quitting intention which were identified in the multiple logistic regression model. Results: Among 1 287 male daily smokers, 24.7% expressed quitting intention within the next 6 months. Four determinants for quitting intention were identified in the multiple logistic regression model, including previous experience of quitting attempt (OR=1.691, 95% CI:1.458-1.962), lower level of smoking intensity (OR=0.751, 95%CI: 0.639-0.884), extensive knowledge on specific health effects of smoking (OR=1.038, 95% CI: 1.001-1.077) and presence of chronic disease (OR=1.765, 95% CI: 1.013-3.075). Results from the dominance analysis showed that 'previous quitting attempt experience' was the most important determinant regarding quitting intention, followed by low smoking intensity, knowledge of the specific health effects of smoking, and the presence of chronic disease. Conclusion: The rate of quitting intention on cigarette smoking among rural male smokers remained low. Quitting intention was associated with previous quit attempt experience.
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Intención , Cese del Hábito de Fumar , China , Estudios Transversales , Humanos , Modelos Logísticos , Masculino , Población Rural , Fumar , TabaquismoRESUMEN
Objective: To explore the influencing factors for the smoking cessation attempts in male current smokers. Methods: This cross-sectional study was conducted in nine villages selected from three counties (Pingyin, Junan and Liangshan) of Shandong province in August, 2010 through household questionnaire survey in villagers aged ≥15 years to collect the information about current smokers demographic characteristics and smoking-related behaviors. A hurdle count data model was used to assess factors associated with the times of past smoking cessation attempts. Results: Among 1 798 male current smokers, 29.53% had at least one smoking cessation attempt. Smokers who were married (ß=0.705, P=0.002), had high educational level (ß=0.214, P=0.026) and had higher level of awareness of smoking risks (ß=0.237, P=0.009) were more likely to have smoking cessation attempt. Young age at smoking initiation (ß=-0.167, P=0.035) and higher level of awareness of smoking risks (ß=0.146, P=0.020) were associated with increased smoking cessation attempts. Conclusions: Less male current smokers had smoking cessation attemps in rural area in Shandong. The factors influencing smoking cessation attempt varied. It is necessary to conduct targeted intervention according to the smokers' smoking cessation experience.
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Cese del Hábito de Fumar , Tabaquismo , Adulto , China , Estudios Transversales , Humanos , Masculino , Persona de Mediana Edad , Población Rural , Fumar , Encuestas y CuestionariosRESUMEN
The goal of this work is to establish the technical feasibility of producing activated carbon from pulp mill sludges. KOH chemical activation of four lignocellulosic biomass materials, two sludges from pulp mills, one sludge for a linerboard mill, and cow manure, were investigated experimentally, with a focus on the effects of KOH/biomass ratio (1/1, 1.5/1 and 2/1), activation temperature (400-600 °C) and activation time (1 to 2 h) on the development of porosity. The activation products were characterized for their physical and chemical properties using a surface area analyzer, scanning electron microscopy and Fourier transform infrared spectroscopy. Experiments were carried out to establish the effectiveness of the lignocellulosic biomass-derived activated carbon in removing methylene blue (MB), a surrogate of large organic molecules. The results show that the activated carbon are highly porous with specific surface area greater than 500 m²/g. The yield of activated carbon was greater than the percent of fixed carbon in the dry sludge, suggesting that the activation process was able to capture a substantial amount of carbon from the organic matter in the sludge. While 400 °C was too low, 600 °C was high enough to sustain a substantial rate of activation for linerboard sludge. The KOH/biomass ratio, activation temperature and time all play important roles in pore development and yield control, allowing optimization of the activation process. MB adsorption followed a Langmuir isotherm for all four activated carbon, although the adsorption capacity of NK-primary sludge-derived activated carbon was considerably lower than the rest, consistent with its lower specific surface area.
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Biomasa , Carbono/química , Carbono/metabolismo , Lignina/química , Lignina/metabolismo , Residuos Industriales , Reciclaje , Aguas del Alcantarillado , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del AguaRESUMEN
Increased levels of stromal cell-derived factor (SDF)-1 occur in certain pathological situations, however the relationship between SDF-1alpha expression and human intervertebral disc herniation is unknown. Vascular endothelial growth factor (VEGF) plays an essential role in the formation of new blood vessels. The present study used immunohistochemistry to measure the expression of SDF-1alpha and VEGF in surgical specimens of human intervertebral discs to evaluate their role in neovascularization. The frequency of expression of SDF-1alpha and VEGF was found to be significantly higher in extruded and sequestrated herniated intervertebral discs compared with bulging, protruding and prolapsed herniated discs and control discs and there was high correlation between SDF-1alpha and VEGF expressions. It is concluded that SDF-1alpha and VEGF are expressed in human intervertebral discs and their interaction may be important in accumulating endothelial progenitor cells during the neovascularization processes in herniated intervertebral discs.
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Quimiocina CXCL12/metabolismo , Hernia/metabolismo , Disco Intervertebral/irrigación sanguínea , Disco Intervertebral/metabolismo , Neovascularización Patológica/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Adolescente , Adulto , Anciano , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana EdadRESUMEN
BACKGROUND/AIMS: The role of high mobility group box chromosomal protein 1 in hepatocellular carcinoma is unknown. The aim of study was to evaluate contributions of high mobility group box chromosomal protein 1 in hepatocellular carcinoma, and analyse the correlation between high mobility group box chromosomal protein 1 and clinicopathologic outcomes. PATIENTS/METHODS: High mobility group box chromosomal protein 1 levels were analysed by Western blot analysis. Edmondson grade, TNM stage and the Cancer of the Liver Italian Program score were used as analysis variables. RESULTS: The serum high mobility group box chromosomal protein 1 levels in hepatocellular carcinoma (84.2 +/- 50.4 ng/ml) was significantly higher than those in chronic hepatitis (39.8 +/- 10.5 ng/ml), liver cirrhosis (40.2 +/- 11.6 ng/ml) and healthy control (7.0 +/- 5.9 ng/ml, p < 0.0001, respectively), and positive correlation were found between high mobility group box chromosomal protein 1 and alpha-fetoprotein (r = 0.952, p < 0.0001), and between high mobility group box chromosomal protein 1 and the size of tumour (r = 0.904, p < 0.0001). High mobility group box chromosomal protein 1 were significant differences among Edmondson grade I, II, III, IV; TNM stage I, II, III, IV and Cancer of the Liver Italian Program score 0-1 points, 2-4 points, > 4 points (p < 0.0001, respectively). CONCLUSIONS: These results suggest that high mobility group box chromosomal protein 1 may be a useful marker for evaluating the tumour stage and predicting prognosis in hepatocellular carcinoma. Targeting high mobility group box chromosomal protein 1 production or release might have potential approaches for hepatocellular carcinoma treatment.
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Carcinoma Hepatocelular/sangre , Proteína HMGB1/sangre , Neoplasias Hepáticas/sangre , Anciano , Biomarcadores/sangre , Western Blotting , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Valor Predictivo de las PruebasRESUMEN
Experiments and reaction equilibrium calculations were carried out for the SO2 gas and oilsands fluid coke system. The goal was to develop a coke-based sulfur-producing flue gas desulfurization (SP-FGD) process that removes SO2 from flue gases and converts it into elemental sulfur. The conversion of SO2 to elemental sulfur proceeded efficiently at temperatures higher than 600 degrees C, and the sulfur yield reached a maximum (> 95%) at about 700 degrees C. An increase of temperature beyond 700 degrees C enhanced the reduction of product elemental sulfur, resulting in the formation of reduced sulfur species (COS and CS2), which lowered the sulfur yield at 900 degrees C to 90%. Although equilibrium calculations suggest that a lower temperature favors the conversion of SO2 as well as the yield of elemental sulfur, experiments showed no formation of elemental sulfur at 600 degrees C and below, likely due to hindered kinetics. Faster reduction of SO2 was observed at a higher temperature in the range of 700-1000 degrees C. A complete conversion of SO2 was achieved in about 8 s at 700 degrees C. Prolonging the product gas--coke contact, the yield of elemental sulfur decreased due to the formation of COS and CS2 while the SO2 conversion remained complete. Equilibrium calculations suggest that the ultimate yield of elemental sulfur maximizes at the C/SO2 ratio of 1, which represents the stoichiometry of SO2 + C-->CO2 + S. For the C/SO2 ratio < 1, equilibrium calculations predict elemental sulfur and CO2 being major products, suggesting that SO2 + C-->CO2 + S is the predominant reaction if SO2 is in excess. Experiments revealed that elemental sulfur and CO2 were only major products if the conversion of SO2 was incomplete, which is in agreement with the result of the equilibrium modeling.
Asunto(s)
Contaminación del Aire/prevención & control , Carbono/química , Coque , Dióxido de Azufre/química , Dióxido de Carbono/química , Incineración , Modelos Teóricos , TemperaturaRESUMEN
The dual effects of nicardipine (Nic) on the automatic activity of sinoatrial (SA) node cell in rabbit heart had been observed using intracellular microelectrodes. Superfused with Nic 0.1, 0.5, 1.0, and 5.0 mumol.L-1 for 10 min, the spontaneous rate was decreased by 32%, 42%, 47%, and 69%, respectively. However, by superfusing with Nic 0.05 mumol.L-1, the spontaneous rate and the amplitude of action potentials were increased by 12% and 13% respectively. Nic 5.0 mumol.L-1 inhibited the positive chronotropic effects of isoproterenol and nicotine. The results suggest that Nic may block the calcium influx in SA node cells.