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1.
Br J Anaesth ; 118(6): 883-891, 2017 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-28541533

RESUMEN

BACKGROUND: : In our preliminary study, the modified Marsh (M-Marsh) model caused an inadvertent underdosing of propofol in underweight patients. However, the predictive performance of the M-Marsh and Schnider models incorporated in commercially available target-controlled infusion (TCI) pumps was not evaluated in underweight patients. METHODS: : Thirty underweight patients undergoing elective surgery were randomly allocated to receive propofol via TCI using the M-Marsh or Schnider models. The target effect-site concentrations (Ces) of propofol were, in order, 2.5, 3, 4, 5, 6 and 2 µg ml -1 . Arterial blood samples were obtained at least 7 min after achieving each pseudo-steady-state. RESULTS: A total of 172 plasma samples were used to determine the predictive performance of both models. The pooled median (95% confidence interval) biases and inaccuracies at a target Ce ≤ 3 µg ml -1 were -22.6 (-28.8 to -12.6) and 31.9 (24.8-36.8) for the M-Marsh model and 9.0 (1.7-16.4) and 28.5 (21.7-32.8) for the Schnider model, respectively. These values at Ce ≥ 4 µg ml -1 were -9.6 (-16.0 to -6.0) and 24.7 (21.1-27.9) for the M-Marsh model and 19.8 (12.9-25.7) and 36.2 (31.4-39.7) for the Schnider model, respectively. CONCLUSIONS: The pooled biases and inaccuracies of both models were clinically acceptable. However, the M-Marsh and Schnider models consistently produced negatively and positively biased predictions, respectively, in underweight patients. In particular, the M-Marsh model showed greater inaccuracy at target Ce ≤ 3 µg ml -1 and the Schnider model showed greater inaccuracy at target Ce ≥ 4 µg ml -1 . Therefore, it is necessary to develop a new pharmacokinetic model for propofol in underweight patients. CLINICAL TRIAL REGISTRATION: KCT0001502.


Asunto(s)
Anestesia General/métodos , Anestesia Intravenosa/métodos , Anestésicos Intravenosos/administración & dosificación , Propofol/administración & dosificación , Delgadez/complicaciones , Adulto , Anestésicos Intravenosos/sangre , Simulación por Computador , Procedimientos Quirúrgicos Electivos , Femenino , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Valor Predictivo de las Pruebas , Propofol/sangre , Estudios Prospectivos , Reproducibilidad de los Resultados , Delgadez/fisiopatología
2.
Dis Esophagus ; 29(7): 752-759, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26471351

RESUMEN

Early detection of synchronous esophageal squamous cell neoplasm (ESCN) in head and neck squamous cell carcinoma (HNSCC) patients can significantly affect their prognosis. We investigated the prevalence of synchronous ESCN and the risk factors for developing ESCN in patients with HNSCC, and evaluated the effect of routine endoscopic screening in these patients. Subjects who were diagnosed as HNSCC from May 2010 to January 2014 were eligible. All patients underwent conventional white light endoscopic examinations with narrow band imaging and Lugol chromoendoscopy. Among 458 subjects screened, 28 synchronous ESCN were detected in 24 patients (5.2%). The prevalence of ESCN was greatest in patients with hypopharyngeal cancer (20.9%). In multivariate analysis, pyriform sinus involvement was independent risk factor for developing synchronous ESCN (odds ratio 171.2, P < 0.001). During the follow-up period (median, 24 months), the 3-year overall survival rates was significantly lower in patients with ESCN than in patients without ESCN (54.2% vs. 78.3%, P = 0.0013). Routine endoscopic screening for detecting synchronous ESCN should be recommended for patients with HNSCC, especially those with pyriform sinus involvement.


Asunto(s)
Carcinoma de Células Escamosas/patología , Detección Precoz del Cáncer/métodos , Neoplasias Esofágicas/diagnóstico , Neoplasias de Cabeza y Cuello/patología , Neoplasias Primarias Múltiples/diagnóstico , Vigilancia de la Población/métodos , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Esofágicas/epidemiología , Neoplasias Esofágicas/patología , Esofagoscopía/métodos , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Hipofaríngeas/patología , Yoduros , Masculino , Persona de Mediana Edad , Análisis Multivariante , Imagen de Banda Estrecha , Neoplasias Primarias Múltiples/epidemiología , Neoplasias Primarias Múltiples/patología , Oportunidad Relativa , Prevalencia , Pronóstico , Estudios Prospectivos , Seno Piriforme/patología , Factores de Riesgo , Carcinoma de Células Escamosas de Cabeza y Cuello , Tasa de Supervivencia , Adulto Joven
3.
Br J Cancer ; 112(3): 608-12, 2015 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-25490528

RESUMEN

BACKGROUND: Although gastric cancer screening is common among countries with a high prevalence of gastric cancer, there is little data to support the effectiveness of this screening. This study was designed to determine the differences in stage at diagnosis of gastric cancer according to the screening history and screening method (upper gastrointestinal series (UGIS) vs endoscopy). METHODS: The study population was derived from the National Cancer Screening Programme (NCSP), a nationwide organised screening programme in Korea. The study cohort consisted of 19 168 gastric cancer patients who had been diagnosed in 2007 and who were invited to undergo gastric cancer screening via the NCSP between 2002 and 2007. RESULTS: Compared with never-screened patients, the odds ratios for being diagnosed with localised gastric cancer in endoscopy-screened patients and UGIS-screened patients were 2.10 (95% CI=1.90-2.33) and 1.24 (95% CI=1.13-1.36), respectively. CONCLUSIONS: Screening by endoscopy was more strongly associated with a diagnosis of localised stage gastric cancer compared with screening by UGIS.


Asunto(s)
Detección Precoz del Cáncer/métodos , Endoscopía Gastrointestinal , Neoplasias Gástricas/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Tamizaje Masivo/métodos , Persona de Mediana Edad , Estadificación de Neoplasias , Evaluación de Programas y Proyectos de Salud , República de Corea
4.
Oral Dis ; 20(8): 773-9, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24735459

RESUMEN

OBJECTIVE: This study assessed trends in the incidence of and survival rates for oral cavity cancer in the Korean population. MATERIALS AND METHODS: Data from the Korea Central Cancer Registry were extracted for 10,282 patients diagnosed with oral cavity cancer (C01-C06) between 1999 and 2010 to evaluate the age-standardised incidence rate, annual percentage change (APC) and 5-year relative survival rate (RSR) according to gender and age. RESULTS: In males, the incidence rate slightly decreased [APC of -0.2% (P = 0.6427)]; in females, the incidence rate increased [APC of 3.1% (P < 0.05)]. In males and females, the incidence of oral tongue cancer (C02) significantly increased [APC of 2.2% and 4.1%, respectively (P < 0.05)]. This increase in oral tongue cancer incidence was most prominent in the younger age group (<40 years, APC = 6.1%, P < 0.05). The incidence of buccal cheek cancer increased only among males [APC of 4.8% (P < 0.05)]. The 5-year RSR improved from 42.7% (1993-1995) to 59.5% (2006-2010), corresponding to an increase of 16.8% from 1993 to 2010 (P < 0.05). CONCLUSION: The incidence of oral cavity cancer in females increased, whereas it stabilised or decreased in males. However, the incidence of oral tongue cancer increased in both males and females, especially in the younger age group.


Asunto(s)
Neoplasias de la Boca/mortalidad , Adulto , Anciano , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/fisiopatología , República de Corea/epidemiología , Tasa de Supervivencia
5.
Support Care Cancer ; 21(2): 511-9, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22842921

RESUMEN

PURPOSE: A prospective cohort study was conducted to analyze whether self-reported fatigue predicts overall survival in patients with esophageal cancer. METHODS: Patients enrolled in the Mayo Clinic Esophageal Adenocarcinoma and Barrett's Esophagus Registry between September 2001 and January 2009 who completed a baseline quality of life instrument were eligible for evaluation. The fatigue component was scored on a 0-10 scale, with 0 as extreme fatigue. Patients were categorized as having a decreased energy level if they reported a score of ≤ 5. Fatigue scores ≥ 6 reflect normal levels of energy. RESULTS: Data from a total of 659 enrolled patients were analyzed. A total of 392 (59 %) and 267 (41 %) patients reported decreased and normal energy, respectively. Univariate analysis indicates patients with normal energy had improved 5-year survival compared to patients with decreased energy (37 vs 28 %, hazard ratio (HR) 0.74, p = 0.006). Among the patients with locally advanced disease, the same relationship was seen (28 vs 17 %, HR = 0.67, p = 0.003); this remained significant on multivariate analysis (HR = 0.71, p = 0.015). CONCLUSIONS: A decreased energy level is associated with poor survival in patients with esophageal cancer. Thus, patients with high levels of fatigue should be referred for psychological support and be considered for therapy aimed at amelioration of fatigue symptoms.


Asunto(s)
Esófago de Barrett/complicaciones , Neoplasias Esofágicas/complicaciones , Fatiga/etiología , Calidad de Vida , Adenocarcinoma/complicaciones , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Esófago de Barrett/mortalidad , Esófago de Barrett/patología , Carcinoma de Células Escamosas/complicaciones , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Neoplasias Esofágicas/mortalidad , Neoplasias Esofágicas/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Sistema de Registros , Perfil de Impacto de Enfermedad , Análisis de Supervivencia , Adulto Joven
6.
Endoscopy ; 44(1): 95-8, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22198779

RESUMEN

The aim of this study was to investigate the possibility of appendiceal orifice inflammation (AOI) as a preceding lesion in the development of ulcerative colitis. A total of 20 patients were identified (mean age 41.2 years; 11 males) who had ulcerative colitis-like inflammatory lesions at the appendiceal orifice without concomitant typical features of ulcerative colitis, such as rectal involvement. A total of 19 patients were followed up endoscopically for a mean duration of 18.4 months (range 2 - 84 months). Typical ulcerative colitis developed in five patients (25 %; four proctitis, one pancolitis) in a mean time of 18.4 months (range 2 - 36 months). Negative conversion of all inflammatory lesions occurred in seven patients (35 %) after a mean follow-up of 20 months (range 3 - 84 months). In the remaining seven patients (35 %), initial lesions did not progress to ulcerative colitis and did not go into remission during a mean follow-up of 16.9 months (range 2 - 42 months). These results suggest that, at least in some cases, AOI precedes development of ulcerative colitis.


Asunto(s)
Apendicitis/complicaciones , Apendicitis/patología , Colitis Ulcerosa/complicaciones , Adulto , Antiinflamatorios no Esteroideos/uso terapéutico , Apendicitis/tratamiento farmacológico , Colitis Ulcerosa/patología , Colonoscopía , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Mesalamina/uso terapéutico , Persona de Mediana Edad , Remisión Espontánea , Factores de Tiempo , Adulto Joven
7.
Dis Esophagus ; 22(8): 676-81, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19222529

RESUMEN

The incidence of adenocarcinoma of the esophagogastric junction (AEG) has been increasing in Western countries. It is unclear, however, whether similar changes are occurring in Asia. We therefore investigated the incidence of AEG in Korea, and assessed the clinical characteristics of three types of AEG based on Siewert's classification. We retrospectively reviewed the medical records of 16 811 patients diagnosed with esophageal squamous cell carcinoma (ESC, n= 1450) or gastric noncardiac adenocarcinoma (GNCA, n= 14 751) between 1992 and 2006. The patients were divided into three 5-year cohorts (cohort A [1992-1996], n= 2734, cohort B [1997-2001], n= 5727, and cohort C [2002-2006], n= 8350), and the ratios of AEG (n= 610) to non-AEG (ESC and GNCA) in each cohort were compared. Using Siewert's classification, the tumors were categorized into one of three types, and patient demographic features and 5-year survival rates were compared. The ratio of AEG to non-AEG cases did not change over time (0.037, 0.034, and 0.039 for cohorts A, B, and C, respectively; P= 0.40). Of the 610 patients with AEG, 23 (3.7%) had type 1 tumors, 47 (7.7%) had type 2, and 540 (88.5%) had type 3. The 5-year survival rate of patients with type 1 AEG was much lower (4.8 +/- 4.7%) than that of those with type 2 (47.9 +/- 7.8%) and type 3 (47.4 +/- 2.5%) tumors. Unlike in Western countries, the ratio of AEG to non-AEG cases has not increased over time in Korea. Type 1 AEG was rarer and associated with a more unfavorable prognosis in Korea than in Western countries.


Asunto(s)
Adenocarcinoma/epidemiología , Neoplasias Esofágicas/epidemiología , Unión Esofagogástrica , Neoplasias Gástricas/epidemiología , Adenocarcinoma/clasificación , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Anciano , Carcinoma de Células Escamosas/clasificación , Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/cirugía , Cardias/patología , Neoplasias Esofágicas/clasificación , Neoplasias Esofágicas/mortalidad , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/cirugía , Femenino , Gastrectomía , Humanos , Estimación de Kaplan-Meier , Corea (Geográfico)/epidemiología , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Prevalencia , Estudios Retrospectivos , Neoplasias Gástricas/clasificación , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/cirugía
8.
Transplant Proc ; 50(4): 1094-1099, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29731073

RESUMEN

BACKGROUND: The connection between renal dysfunction and cardiovascular dysfunction has been consistently shown. In patients with liver cirrhosis, renal dysfunction shows a tight correlation with prognosis after liver transplantation (LT); therefore, precise renal assessment is mandatory. Cystatin C, a sensitive biomarker for assessing renal function, has shown superiority in detecting mild renal dysfunction compared to classical biomarker creatinine. In this study, we aimed to compare cystatin C and creatinine in predicting 30-day major cardiovascular events (MACE) and all-cause mortality in LT recipients with normal serum creatinine levels. PATIENTS AND METHODS: Between May 2010 and October 2015, 1181 LT recipients (mean Model for End-stage Liver Disease score 12.1) with pretransplantation creatinine level ≤1.4 mg/dL were divided into tertiles according to each renal biomarker. The 30-day MACE was a composite of troponin I >0.2 ng/mL, arrhythmia, congestive heart failure, death, and cerebrovascular events. RESULTS: The highest tertile of cystatin C (≥0.95 mg/L) was associated with a higher risk for a 30-day MACE event (odds ratio: 1.62; 95% confidence interval: 1.07 to 2.48) and higher risk of death (hazard ratio: 1.96; 95% confidence interval: 1.04 to 3.67) than the lowest tertile (<0.74 mg/L) after multivariate adjustments. However, the highest tertile of creatinine level showed neither increasing MACE event rate nor worse survival rate compared with the lowest tertile (both insignificant after multivariate adjustment). CONCLUSIONS: Pretransplantation cystatin C is superior in risk prediction of MACE and all-cause mortality in LT recipients with normal creatinine, compared to creatinine. It would assist further risk stratification which may not be detected with creatinine.


Asunto(s)
Biomarcadores/sangre , Enfermedades Cardiovasculares/epidemiología , Creatinina/sangre , Cistatina C/sangre , Fallo Hepático/complicaciones , Trasplante de Hígado/mortalidad , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Tasa de Supervivencia
9.
Transplant Proc ; 50(4): 1123-1128, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29731078

RESUMEN

BACKGROUND: Many studies have reported the negative influence of diabetes and hypertension on morbidity and mortality in the general population. In liver transplantation (LT) recipients, prevalence of nonalcoholic fatty liver disease and metabolic syndrome is increasing. Hence, concerns over the negative influence of metabolic syndrome, including diabetes and hypertension, are growing. However, there have been few studies about the outcomes of LT recipients with diabetes with/without hypertension. We aimed to evaluate the impact of diabetes with/without hypertension on the outcomes of LT. METHODS: Between May 2010 and October 2015, 814 LT recipients (median age, 51 [46-55] years; median MELD score, 13 [9-18]), without overt cardiovascular disease were retrospectively evaluated. To rigorously adjust for clinically confounding factors, a 1:2 propensity score matching analysis was performed. Kaplan-Meier survival curves and Cox proportional hazard regression analysis were performed to examine the association between diabetes with/without hypertension and all-cause mortality or graft survival rate. RESULTS: There were 77 (9.5%) graft failures and 71 (8.7%) deaths during a median follow-up of 2.4 years. After 1:2 matching of 173 (21.3%) diabetic patients, no significant differences were evident in graft survival rate (log-rank test, P = .46; and hazard ratio [HR], 1.06; 95% confidence interval [CI], 0.55-2.06; P = .865) and all-cause mortality (log-rank test, P = .59; and HR, 1.06; 95% CI, 0.55-2.06; P = .727). Separate 1:2 matching was applied to a subgroup of 43 (5.3%) patients with diabetes and hypertension. This matching also showed no difference in graft survival rate (log-rank test, P = .45; and HR, 1.35; 95% CI, 0.43-4.27; P = .613) and all-cause mortality (log-rank test, P = .25; and HR, 1.87; 95% CI, 0.54-6.50; P = .325). CONCLUSION: Diabetes with/without hypertension does not have an impact on graft survival rate or all-cause mortality in LT recipients.


Asunto(s)
Complicaciones de la Diabetes/complicaciones , Hipertensión/complicaciones , Trasplante de Hígado/mortalidad , Adulto , Complicaciones de la Diabetes/mortalidad , Diabetes Mellitus , Femenino , Supervivencia de Injerto , Humanos , Hipertensión/mortalidad , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Puntaje de Propensión , Modelos de Riesgos Proporcionales , Análisis de Regresión , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia , Resultado del Tratamiento
10.
Transplant Proc ; 50(4): 1136-1141, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29731081

RESUMEN

BACKGROUND: Antiphospholipid antibodies (aPL), including anticardiolipin (aCL), anti-ß2-glycoprotein I (anti-ß2GPI), and lupus anticoagulant (LA) antibodies, are frequently found in liver cirrhosis and associated with splanchnic vein thrombosis. Although the risk factors of early allograft dysfunction (EAD) are known, the association between EAD and aPL has been poorly investigated. We hypothesized that LA, potent aPL with thrombotic potential, may be associated with EAD development after living donor liver transplantation (LDLT). METHODS: Data of 719 patients who underwent LDLT from February 2014 to June 2016 at our center were retrospectively collected and analyzed. Patients were divided into 2 groups according to the positivity of LA screening test (LA group [n = 148] vs no-LA group [n = 571]). Risk factors for EAD were investigated using multivariable regression analysis and inverse probability of treatment weighting (IPTW) of propensity scores. RESULTS: The prevalence of LA screening positivity, confirmatory test positivity, and EAD was 20.6%, 1.1%, and 11.3%, respectively. aCL positivity rate was 7.5% and anti-ß2GPI positivity rate was 7.0%. The EAD prevalence in LA and no-LA group was 25.7% and 7.5%, respectively. However, multivariable and IPTW analyses showed no association between EAD and LA screening positivity (P = .263 and P = .825, respectively), although a significant association was found in univariate analysis (odds ratio, 4.242; P < .001). Model for End-stage Liver Disease score, operation time, and C-reactive protein level remained significant after multivariable analysis. CONCLUSION: A positive LA screening test result was associated with EAD only in the univariate analysis. Inflammation, based on C-reactive protein level, was more important for EAD development.


Asunto(s)
Síndrome Antifosfolípido/epidemiología , Trasplante de Hígado/efectos adversos , Inhibidor de Coagulación del Lupus/sangre , Adulto , Anciano , Aloinjertos , Síndrome Antifosfolípido/sangre , Síndrome Antifosfolípido/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Prevalencia , Estudios Retrospectivos , Factores de Riesgo
11.
Neurogastroenterol Motil ; 30(9): e13376, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29797379

RESUMEN

BACKGROUND: Conventional anorectal manometric parameters based on linear waves cannot properly predict balloon expulsion (BE) time. We aimed to determine the correlation between integrated pressurized volume (IPV) parameters during simulated evacuation (SE) and BE time in healthy individuals and constipated patients and to assess the correlation between each parameter and symptoms. METHODS: A total of 230 male participants (including 26 healthy volunteers and 204 chronically constipated patients) underwent high-resolution anorectal manometry (HRAM) and BE tests. The IPV was calculated by multiplying the amplitude, distance, and time from the HRAM profile. Receiver operating characteristic curve (ROC) analysis and partial least square regression (PLSR) were performed. KEY RESULTS: ROC analysis indicated that the IPV ratio between the upper 1 cm and lower 4 cm of the anal canal was more effective for predicting BE time (area under the curve [AUC]: 0.74, 95% confidence interval [CI]: 0.67-0.80, P < .01) than the conventional anorectal parameters, including defecation index and rectoanal gradient (AUC: 0.60, 95% CI: 0.52-0.67, P = .01). PLSR analysis of a linear combination of IPV parameters yielded an AUC of 0.79. Moreover, the IPV ratio showed a greater clinical correlation with patient symptoms than conventional parameters. CONCLUSIONS AND INFERENCES: The IPV parameters and the combination of IPV parameters via PLSR were more significantly correlated with BE time than the conventional parameters. Thus, this study presents a useful diagnostic tool for the evaluation of pathophysiologic abnormalities in dyssynergic defecation using IPV and BE time.


Asunto(s)
Estreñimiento/diagnóstico , Manometría/métodos , Adulto , Anciano , Canal Anal/fisiopatología , Estreñimiento/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Presión , Recto/fisiopatología
12.
Water Sci Technol ; 56(1): 123-30, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17711007

RESUMEN

The Hydrological Simulation Program-FORTRAN (HSPF) is a comprehensive model that was developed to simulate many processes related to water flow and quality in watersheds of almost any size and complexity. Paddy rice fields often dominate extensive portions of the landscape in the Asian monsoon region. The hydrological and environmental conditions of paddy fields differ somewhat from those of other land uses, and HSPF may not adequately simulate watersheds in paddy farming regions. HSPF was previously modified to HSPF-Paddy; here, we examined the applicability of the modified model. The model was applied to simulate the water flow and quality of the Saemangeum watershed (2523 km2) in Korea, where paddy rice fields comprise about one-third of the total watershed area. Long-term monitoring data (5 years for water flow, 10 years for water quality) were used in the calibration and verification processes. Model performance was in the range of "very good" and "good" based on model efficiency (R2) and percent difference. The accuracy of the daily simulation was lower than that of monthly simulation for water flow. The water-quality simulation results were encouraging for this sizable watershed with mixed land uses; HSPF-Paddy proved adequate, and its application is recommended to simulate watershed processes in paddy farming regions.


Asunto(s)
Simulación por Computador , Ríos , Movimientos del Agua , Calibración , Corea (Geográfico) , Nitrógeno/química , Oxígeno/química , Fósforo/química , Programas Informáticos , Factores de Tiempo
13.
Water Sci Technol ; 56(8): 31-9, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17978430

RESUMEN

Uncertainty in water quality model predictions is inevitably high due to natural stochasticity, model uncertainty, and parameter uncertainty. An integrated modelling system (modified-BASINS) under uncertainty is described and demonstrated for use in receiving-water quality prediction and watershed management. A Monte Carlo simulation was used to investigate the effect of various uncertainty types on output prediction. Without pollution control measures in the watershed, the concentrations of total nitrogen (T-N) and total phosphorus (T-P) in the Hwaong Reservoir, considering three uncertainty types, would be less than about 4.4 and 0.23 mg L(-1), respectively, in 2012, with 90% confidence. The effects of two watershed management practices, wastewater treatment plants (WWTP) and constructed wetlands (WETLAND), were evaluated. The combined scenario (WWTP + WETLAND) was the most effective at improving reservoir water quality, bringing concentrations of T-N and T-P in the Hwaong Reservoir to less than 3.4 and 0.14 mg L(-1), 24 and 41% improvements, respectively, with 90% confidence. Overall, the Monte Carlo simulation in the integrated modelling system was practical for estimating uncertainty and reliable in water quality prediction. The approach described here may allow decisions to be made based on the probability and level of risk, and its application is recommended.


Asunto(s)
Modelos Teóricos , Incertidumbre , Contaminación del Agua/prevención & control , Abastecimiento de Agua , Geografía , Corea (Geográfico) , Método de Montecarlo , Movimientos del Agua
14.
Water Sci Technol ; 55(1-2): 267-73, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17305149

RESUMEN

A study was performed to examine the effects of reclaimed-water irrigation on microorganism concentration in the ponded-water of paddy rice plots. Several treatments were used and each one was triplicated to evaluate the change of indicator microorganisms (total coliforms (TC), faecal coliforms (FC), and E. coli) concentrations in 2003 and 2004 growing seasons. Their concentrations increased significantly after irrigation, but decreased by approximately 45% in 24 h. It implies that agricultural activities such as ploughing and fertilising need to be practiced one or two days after irrigation, considering health risks. Treatments with UV-disinfected water irrigation, demonstrated significantly lower concentrations than others, including control plots where natural water was irrigated. The monitoring result from actual paddy rice fields and experimental paddy plots showed that concentrations of indicator microorganisms ranged from 10(2) to 10(5) MPN/100 mL. The field scale water reuse research project is in progress and national guidelines for reclaimed-water irrigation are under preparation in Korea. A comprehensive assessment of existing agricultural practices and a thorough monitoring in the fields as well as treatment plots are recommended to make national guidelines more representative.


Asunto(s)
Agricultura , Eliminación de Residuos Líquidos , Microbiología del Agua , Conservación de los Recursos Naturales , Oryza
15.
Transplant Proc ; 49(5): 1076-1081, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28583531

RESUMEN

BACKGROUND: Measuring activated clotting time (ACT) is widely performed to monitor heparin therapy. Regardless of anticoagulant use, ACT is affected by coagulopathies such as coagulation factor deficiency and thrombocytopenia. However, its use in end-stage liver disease (ESLD) with complex coagulopathy is not well characterized. We evaluated whether ACT could be used to detect innate coagulopathy in ESLD patients. METHODS: We retrospectively assessed Hemochron (International Technidyne, Edison, NJ, USA) ACT (FTCA 510, normal range 105-167 seconds) and INTEM clotting time (CT) of rotational thromboelastometry (ROTEM; ROTEM delta, Pentapharm GmbH, Munich, Germany) (100-240 seconds) in 366 liver transplantation (LT) recipients, simultaneously measured before anesthetic induction for LT. Multiple linear regression analyses helped identify the factors related to ACT in ESLD patients. The relationship between ACT and INTEM CT was evaluated by Spearman rank correlation analysis and receiver operating characteristic curve. RESULTS: Median ACT was 143 seconds (range 73-295 seconds), and 60 patients (16.4%) had ACTs of >167 seconds. Multiple regression analyses revealed that prolonged prothrombin time, activated partial thromboplastin time, low antithrombin III, and young age were associated with high ACT levels. INTEM CT was associated with ACT independent of liver disease severity, while EXTEM CT was not. ACT was moderately correlated with INTEM CT (r = 0.535), and the optimal cutoff value of ACT for predicting INTEM CT >240 seconds was 151 seconds (area under the curve = 0.787). CONCLUSIONS: In ESLD patients, ACT is effective in detecting prolonged INTEM CT. Therefore, ACT may be used to predict intrinsic pathway defects with a cutoff value of 151 seconds, suggesting feasibility when ROTEM is unavailable.


Asunto(s)
Trastornos de la Coagulación Sanguínea/diagnóstico , Pruebas de Coagulación Sanguínea/métodos , Enfermedad Hepática en Estado Terminal/complicaciones , Adulto , Trastornos de la Coagulación Sanguínea/sangre , Femenino , Alemania , Humanos , Masculino , Persona de Mediana Edad , Curva ROC , Estudios Retrospectivos
16.
Transplant Proc ; 49(5): 1092-1096, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28583534

RESUMEN

BACKGROUND: The importance of heart rate (HR) measurement as a prognostic factor has been recognized in many clinical conditions, such as hypertension, coronary artery disease, or heart failure. Patients with liver cirrhosis tend to have increased resting HR as consequence of hyperdynamic circulation. In the current study, we examined whether pretransplant resting increased HR is associated with overall mortality in cirrhotic patients following liver transplantation (LT). PATIENTS AND METHODS: We retrospectively collected and analyzed the data of 881 liver recipients who underwent LT surgery between October 2009 and September 2012. Patients were categorized into 3 groups by tertile of resting HR as follows: tertile 1 group, HR ≤ 65 beats per minute (bpm); tertile 2 group, HR 66 to 80 bpm; and tertile 3 group, HR > 80 bpm. RESULTS: Kaplan-Meier analysis showed that the all-cause mortality rate was significantly different according to tertiles of HR (P = .016, log-rank test). The multivariate Cox regression analysis showed that tertile 3 group was significantly associated with higher risk for all-cause mortality (hazard ratio 1.83, 95% confidence interval, 1.10-3.07; P = .021) compared with tertile 1 group, after adjusting for clinically significant variables in univariate analysis. CONCLUSIONS: Our results demonstrate that pretransplant resting tachycardia can identify patients at high risk of death in cirrhotic patients following LT, suggesting that further study will be need to clarify relationship between HR burden and sympathetic cardiac neuropathy.


Asunto(s)
Frecuencia Cardíaca , Trasplante de Hígado/mortalidad , Anciano , Femenino , Humanos , Estimación de Kaplan-Meier , Cirrosis Hepática/cirugía , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo
17.
Water Sci Technol ; 53(1): 25-32, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16532732

RESUMEN

Applicability of a widely accepted watershed-based water quality assessment tool (BASINS) and its associated watershed model (WinHSPF) was evaluated on the Seamangeum watershed in Korea. The study site is the largest polder project area in Korea and its environmental quality has been debated for the last five years. BASINS was found to be a convenient and powerful tool for assessment of watershed characteristics, and provided various tools to delineate the watershed into land segments and river reaches, reclassify land use, and parameterize for WinHSPF simulation. Calibration results were satisfactory showing model efficiency over 0.80 for stream flow, temperature, and dissolved oxygen simulation, and model output for water quality constituents also reasonably matched the observed data. It was demonstrated that calibration with dry-day data for a relatively long period might be adequate to simulate hydrologic characteristics and water quality of the watershed with WinHSPF, and using parameters generated with BASINS for nonpoint source pollution simulation is suggested when enough wet-day monitoring data are not available. The unit-area load of biochemical oxygen demand, total nitrogen, and total phosphorus was 27.8, 48.2, and 4.3 kg/ha/yr, respectively. These values are within the expected range but on the high side of the reported values, which implies that effective control measures are required to protect water quality of the downstream reservoir. Overall, BASINS/WinHSPF was applicable and found to be a powerful tool in pollutant loading estimation from the watershed, and its use in Korea is recommended.


Asunto(s)
Modelos Teóricos , Contaminantes del Agua/análisis , Abastecimiento de Agua , Calibración , Monitoreo del Ambiente , Corea (Geográfico) , Oxígeno/análisis , Oxígeno/química , Agua/química
18.
Water Sci Technol ; 53(2): 253-61, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16594344

RESUMEN

A water quality model applicable to rice paddies was developed using field data from 1999-2002. Use of the Dirac delta function efficiently explained the nutrient-concentration characteristics of ponded water. The model results agreed reasonably well with the observed data. The ponded-water quality was influenced primarily by fertilization; nutrient concentration was especially high during early cultivation periods. Reducing surface drainage during the fertilization period may substantially reduce nonpoint source loading from paddies. Increased weir heights and shallow irrigation methods were evaluated by the model as practical methods for reducing nutrient loading from paddies. These methods were effective in reducing surface drainage and are suggested as "best management practices" (BMPs) if applied based on site-specific paddy conditions.


Asunto(s)
Agricultura/métodos , Monitoreo del Ambiente/métodos , Contaminantes Químicos del Agua/análisis , Fertilizantes , Corea (Geográfico) , Modelos Teóricos , Nitrógeno , Oryza , Residuos de Plaguicidas/análisis , Fósforo , Lluvia , Contaminantes del Suelo , Movimientos del Agua , Contaminación del Agua , Abastecimiento de Agua
19.
Green Chem ; 17(5): 2736-2740, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-26421000

RESUMEN

We have developed an effective method that converts a variety of mono- and disaccharides into formic acid predominantly. Our recyclable NHC-amidate palladium(II) catalyst facilitated oxidative degradation of carbohydrates without using excess oxidant. Stoichiometric amounts of hydrogen peroxide and sodium hydroxide were employed at ambient temperatures.

20.
Neurogastroenterol Motil ; 27(6): 787-95, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25807997

RESUMEN

BACKGROUND: The beneficial effect of biofeedback therapy (BFT) over a period of more than 2 years has not been studied in a large group of patients. The aim of this study was to evaluate the long-term efficacy of BFT for dyssynergic defecation (DD). METHODS: We evaluated the results for 347 consecutive constipated patients with DD who underwent BFT for a median of five sessions between 2004 and 2009. Initial responses were assessed immediately after the completion of BFT. A responder was defined as a subject with at least a three-point improvement from before to after BFT on an 11-point global bowel satisfaction (GBS) scale, or a two-point improvement if the baseline GBS was more than six points. The probability of remaining a responder was estimated by non-parametric maximum likelihood estimation. KEY RESULTS: The initial response rate to BFT was 72.3% (n = 251), Parkinson's disease and higher baseline GBS scores were associated with initial non-response. The long-term efficacy of BFT was analyzed in 103 patients who were followed up for more than 6 months; the initial effects of BFT were maintained in 85 of the patients (82.5%) during a median of 44 months of follow-up (IQR = 12-68). The probability of remaining a responder was 60% at 2 years, and 58% at 5 years. CONCLUSIONS & INFERENCES: The efficacy of BFT is maintained for more than 2 years after BFT in a considerable proportion of constipated patients with DD. BFT is effective and durable treatment for managing DD.


Asunto(s)
Ataxia/terapia , Biorretroalimentación Psicológica/métodos , Estreñimiento/terapia , Anciano , Canal Anal , Estudios de Cohortes , Defecación , Femenino , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Masculino , Manometría , Persona de Mediana Edad , Recto , Estudios Retrospectivos , Resultado del Tratamiento
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