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3.
Lupus ; 27(10): 1644-1651, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29950160

RESUMEN

Objectives Avascular necrosis (AVN) is one of the most common causes of organ damage in patients with systemic lupus erythematosus (SLE) and often causes serious physical disability. The aims of this study were to investigate clinical risk factors associated with symptomatic AVN and to analyze their synergistic effects in a large SLE cohort in Korea. Methods Patients with SLE were enrolled and followed from 1998 to 2014 in the Hanyang BAE Lupus cohort, and damage was measured annually according to the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI). AVN was confirmed by imaging study if patients had symptoms. To determine risk factors for AVN, clinical, laboratory and therapeutic variables were analyzed by logistic regression. Relative excess risk due to interaction (RERI), attributable proportion (AP), and synergy index (S) were calculated to measure interactions between significant variables. Results Among 1219 SLE patients, symptomatic AVN was the most common type of musculoskeletal damage (10.8%, n = 132). SLE patients with AVN showed an earlier onset age, demonstrated AVN more commonly in conjunction with certain other clinical manifestations such as renal and neuropsychiatric disorders, and received significantly higher total cumulative corticosteroid dose and immunosuppressive agents than did patients without AVN. However, in multivariable analysis, only two variables including use of a cumulative corticosteroid dose greater than 20 g (odds ratio (OR) 3.62, p = 0.015) and use of immunosuppressants including cyclophosphamide or mycophenolate mofetil (OR 4.51, p < 0.001) remained as significant risk factors for AVN. Patients with cumulative corticosteroid dose > 20 g and immunosuppressant use had a 15.44-fold increased risk for AVN, compared with patients without these risk factors ( p < 0.001). RERI, AP and S, which define the strength of interactions between two risk factors, were 9.01 (95% confidence interval (CI) 1.30-16.73), 0.58 (95% CI 0.36-0.81) and 2.66 (95% CI 1.42-4.99), respectively, supporting the presence of synergistic interactions in the development of symptomatic AVN in our Korean lupus cohort. Conclusions An individual risk assessment for AVN development should be made prior to and during treatment for SLE, especially in patients with high-dose corticosteroid and immunosuppressant use regardless of clinical manifestations and disease activity.


Asunto(s)
Corticoesteroides/efectos adversos , Inmunosupresores/efectos adversos , Lupus Eritematoso Sistémico/tratamiento farmacológico , Osteonecrosis/inducido químicamente , Adolescente , Corticoesteroides/administración & dosificación , Adulto , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Femenino , Humanos , Inmunosupresores/administración & dosificación , Lupus Eritematoso Sistémico/diagnóstico , Masculino , Osteonecrosis/diagnóstico , Estudios Prospectivos , República de Corea , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
4.
Br J Cancer ; 106(9): 1469-74, 2012 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-22460270

RESUMEN

BACKGROUND: Docetaxel is widely used as a chemotherapeutic agent for gastric cancer treatment. A combined regimen with sunitinib demonstrated a synergistic antitumour effect in a preclinical model. The aim of this study was to evaluate the efficacy and safety of this combination in patients with unresectable or metastatic advanced gastric cancer following failure of treatment with a fluoropyrimidine and platinum combination. METHODS: This open-label, phase II, randomised trial enrolled patients with unresectable or metastatic gastric cancer. Patients were assigned to either a docetaxel monotherapy arm (D only arm: 60 mg m(-2), every 3 weeks) or a combination arm (DS arm: docetaxel+sunitinib 37.5 mg every day). The primary end point of the study was time to progression and the secondary end points were overall response rate, disease control rate, overall survival, and toxicity profile. A pharmacokinetic study was also performed. RESULTS: A total of 107 patients were entered into the study. The TTP was not significantly prolonged in the DS arm when compared with the D only arm (DS vs D only arm: 3.9 months (95% confidence interval (CI) 2.9-4.9) vs 2.6 months (95% CI 1.8-3.5) (P=0.206). The hazard ratio for TTP was 0.77 (95% CI 0.52-1.16). However, the objective response rate was significantly higher in the DS arm (41.1% vs 14.3%, P=0.002). Patients in the DS arm experienced stomatitis, diarrhoea, and hand-foot syndrome more frequently. CONCLUSION: The addition of sunitinib to docetaxel did not significantly prolong TTP, although it significantly increased response.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Terapia Recuperativa , Neoplasias Gástricas/tratamiento farmacológico , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/mortalidad , Adenocarcinoma/secundario , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Neoplasias Óseas/mortalidad , Neoplasias Óseas/secundario , Docetaxel , Femenino , Fluorouracilo/administración & dosificación , Humanos , Indoles/administración & dosificación , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/secundario , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/secundario , Metástasis Linfática , Masculino , Persona de Mediana Edad , Platino (Metal)/administración & dosificación , Pirroles/administración & dosificación , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/patología , Sunitinib , Tasa de Supervivencia , Taxoides/administración & dosificación , Distribución Tisular , Resultado del Tratamiento , Adulto Joven
5.
Ann Oncol ; 22(7): 1636-1643, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21220520

RESUMEN

BACKGROUND: The incidence and risk factors of central nervous system (CNS) involvement in peripheral T-cell lymphomas (PTCLs) are still unclear. PATIENTS AND METHODS: We analyzed 228 patients with PTCLs, excluding cases of extranodal natural killer/T-cell lymphoma and primary cutaneous T-cell lymphoma, by retrospectively collecting the clinical features and outcomes of the patients. RESULTS: Twenty events (8.77%, 20/228) of CNS involvement were observed during a median follow-up period of 13.9 months (range 0.03-159.43). Based on univariate analysis, elevated serum lactate dehydrogenase (LDH) level [P = 0.019, relative risk (RR) 5.904, 95% confidence interval (CI) 1.334-26.123] and involvement of the paranasal sinus (P = 0.032, RR 3.137, 95% CI 1.105-8.908) adversely affect CNS involvement. In multivariate analysis, both were independently poor prognostic factors for CNS relapse [elevated LDH level: P = 0.011, hazard ratio (HR) 6.716, 95% CI 1.548-29.131; involvement of the paranasal sinus: P = 0.008, HR 3.784, 95% CI 1.420-10.083]. The survival duration of patients with CNS involvement was significantly shorter than that of the patients without CNS involvement (P = 0.009), with median overall survival of 7.60 months (95% CI of 4.92-10.28) versus 27.43 months (95% CI of 0.00-57.38), respectively. CONCLUSIONS: Elevated LDH level and involvement of the paranasal sinus are two risk factors for CNS involvement in patients with PTCLs. Considering the poor prognoses after CNS relapse, prophylaxis should be considered with the presence of any risk factor.


Asunto(s)
Neoplasias del Sistema Nervioso Central/sangre , Neoplasias del Sistema Nervioso Central/diagnóstico , L-Lactato Deshidrogenasa/sangre , Linfoma de Células T Periférico/sangre , Neoplasias de los Senos Paranasales/sangre , Neoplasias de los Senos Paranasales/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias del Sistema Nervioso Central/etiología , Ciclofosfamida/uso terapéutico , Doxorrubicina/uso terapéutico , Femenino , Estudios de Seguimiento , Humanos , Linfoma de Células T Periférico/complicaciones , Linfoma de Células T Periférico/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Neoplasias de los Senos Paranasales/etiología , Prednisona/uso terapéutico , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia , Resultado del Tratamiento , Vincristina/uso terapéutico , Adulto Joven
6.
J Obstet Gynaecol ; 30(3): 277-80, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20373931

RESUMEN

This study was conducted to report 10 cases of Fitz-Hugh-Curtis Syndrome (FHCS) diagnosed with CT and 101 cases of FHCS-like lesion that suggested perihepatitis during laparoscopic surgery. We reviewed retrospectively the images of 3,674 laparoscopies for obstetrical and gynaecological diseases and analysed 10 cases of FHCS diagnosed by clinical patterns and CT. All the 10 cases showed liver capsular enhancement on CT. Among the 3,674 laparoscopies, we found 101 cases (2.7%) with FHCS like lesion. Among them, 23 cases were during laparoscopic procedure for endometriosis, 16 for gynaecological malignant tumours, 16 for benign adnexal diseases excluding endometriosis, 13 for uterine leiomyoma, 7 for pelvic inflammatory disease, 2 had peritoneal tuberculosis and 21 for other gynaecological diseases. Further consideration should be given for the causes of FHCS other than N. gonorrhoeae and C. trachomatis. Because FHCS may represent various clinical phases, other considerations and clinical classifications are necessary for treatment.


Asunto(s)
Hepatitis/complicaciones , Enfermedad Inflamatoria Pélvica/complicaciones , Adulto , Femenino , Hepatitis/diagnóstico por imagen , Humanos , Laparoscopía , Síndrome , Tomografía Computarizada por Rayos X , Adulto Joven
7.
J Cell Biol ; 145(5): 1089-102, 1999 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-10352024

RESUMEN

The architectural complexity of the hepatocyte canalicular surface has prevented examination of apical membrane dynamics with methods used for other epithelial cells. By adopting a pharmacological approach, we have documented for the first time the internalization of membrane proteins from the hepatic apical surface. Treatment of hepatocytes or WIF-B cells with phosphoinositide 3-kinase inhibitors, wortmannin or LY294002, led to accumulation of the apical plasma membrane proteins, 5'-nucleotidase and aminopeptidase N in lysosomal vacuoles. By monitoring the trafficking of antibody-labeled molecules, we determined that the apical proteins in vacuoles came from the apical plasma membrane. Neither newly synthesized nor transcytosing apical proteins accumulated in vacuoles. In wortmannin-treated cells, transcytosing apical proteins traversed the subapical compartment (SAC), suggesting that this intermediate in the basolateral-to-apical transcytotic pathway remained functional. Ultrastructural analysis confirmed these results. However, apically internalized proteins did not travel through SAC en route to lysosomal vacuoles, indicating that SAC is not an intermediate in the apical endocytic pathway. Basolateral membrane protein distributions did not change in treated cells, uncovering another difference in endocytosis from the two domains. Similar effects were observed in polarized MDCK cells, suggesting conserved patterns of phosphoinositide 3-kinase regulation among epithelial cells. These results confirm a long-held but unproven assumption that lysosomes are the final destination of apical membrane proteins in hepatocytes. Significantly, they also confirm our hypothesis that SAC is not an apical endosome.


Asunto(s)
Endocitosis/fisiología , Hígado/fisiología , Lisosomas/fisiología , Proteínas de la Membrana/metabolismo , Fosfatidilinositol 3-Quinasas/fisiología , Androstadienos/farmacología , Animales , Polaridad Celular , Células Cultivadas , Endocitosis/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Hígado/citología , Masculino , Inhibidores de las Quinasa Fosfoinosítidos-3 , Ratas , Ratas Sprague-Dawley , Transducción de Señal , Wortmanina
8.
J Nanosci Nanotechnol ; 7(10): 3394-9, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18330146

RESUMEN

Single-wall carbon nanotubes (SWCNTs) were laterally grown on SiO2/Si substrates by means of an "all-laser" growth process. Our "all-laser" process stands out by its exclusive use of the same pulsed UV laser, first, to deposit the CoNi nanocatalyst and, second, to grow SWCNTs through the laser ablation of a pure graphite target. The "all-laser" grown SWCNTs generally self-assemble into bundles (5-15 nm-diam.) sprouting from the CoNi nanocatalyst and laterally bridging the 2 microm gap separating adjacent catalysed electrodes (in either "suspended" or "on-substrate" geometries). A comparative study of the oxidation resistance of both suspended and on-substrate SWCNTs was achieved. The "all-laser" grown SWCNTs were subjected to annealing under flowing oxygen at temperatures ranging from 200 to 1100 degrees C. Systematic scanning electron microscopy observations combined with micro-Raman analyses revealed that more than 20% of suspended nanotubes were still stable at temperatures as high as 900 degrees C under flowing O2 while the on-substrate counterpart were completely burnt out at this temperature. Accordingly, the activation energy, as deduced from the Arrhenius plot, of the suspended SWCNTs is found to be as high as approximately 180 kJ mol(-1) (approximately 9 times higher than that of the on-substrate ones). The high quality (almost defect-free) of the nanotubes synthesized by the "all-laser" approach, their protected tips into the embedded CoNi catalyst nanolayer together with their suspended geometry are thought to be responsible for their unprecedented ultra-high oxidation resistance. This opens up new prospects for the use of these suspended nanotubes into nanodevices that have to operate under highly oxidizing environments.


Asunto(s)
Cristalización/métodos , Rayos Láser , Nanotecnología/métodos , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestructura , Sustancias Macromoleculares/química , Ensayo de Materiales , Conformación Molecular , Oxidación-Reducción , Tamaño de la Partícula , Propiedades de Superficie , Temperatura
9.
Orthop Traumatol Surg Res ; 103(3): 461-464, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28274882

RESUMEN

BACKGROUND: Few studies have been conducted to explore the use of the vacuum sealing drainage (VSD) technique in complex hand injuries. The aim of this study was to report outcomes in patients with complex hand injuries receiving VSD as a coadjuvant treatment prior to second-stage surgery. METHODS: This case series study retrospectively reviewed the patients who underwent VSD for treatment of hand injuries. Inclusion criteria for the study were: (1) traumatic soft tissue defects of the hand and wrist, accompanied by different degrees of injury and exposure of bone, tendon, or blood vessel; (2) the wound surface of hand and wrist was seriously contaminated and direct wound closure was not possible; and (3) the soft tissues of hand and wrist were seriously lacerated or avulsed, and showed necrosis or acute infection. After debridement, one-stage and/or two-stage repairs using healthy adjacent tissues were performed and the wound was covered by the VSD materials. The non-cytotoxic polyethylene alcohol hydration seaweed salt foam was applied during the VSD treatment for its good biocompatibility. The drainage tube was connected to the vacuum equipment and the negative pressures were set at -60kPa to -40kPa. The VSD device was left in place for 5 to 7 days before removal. Either free skin grafting or skin flap transplantation was used for wound closure and/or reconstructive surgery. The hand injury severity score was used to assess wound severity. The surgical results were scored using the total active motion classification. RESULTS: A total of 17 patients (13 and 4 patients had major and severe hand injuries), averaging 33.8 years were included. During the study period, 6 patients with severe hand injuries were not treated with VSD for the following reasons: (1) hemodynamic instability (n=1); (2) impaired coagulation function (n=1); (3) uncontrollable hemorrhage on the wound surface (n=2); and (4) exposure of the main blood vessels after surgical repair (n=2). VSD treatment was performed for an average of 7.4 days (range, 6-14 days) and the duration of wound healing averaged 23 days (range, 20-43 days). Wound infection was not reported prior to second-stage surgery. Only one of 17 patients had superficial necrosis at the flap edge, for a success rate of 94%. Average follow-up was 8.7 months (range, 4-13 months). Twelve (71%) patients reported excellent or good, four (23%) reported fair, and one (6%) reported poor results. CONCLUSION: The VSD can effectively promote safe and rapid repair of local soft tissues with good prognosis.


Asunto(s)
Traumatismos de la Mano/terapia , Terapia de Presión Negativa para Heridas , Cuidados Preoperatorios/métodos , Traumatismos de los Tejidos Blandos/terapia , Adulto , Desbridamiento , Femenino , Humanos , Masculino , Procedimientos de Cirugía Plástica , Estudios Retrospectivos , Trasplante de Piel , Colgajos Quirúrgicos , Factores de Tiempo , Resultado del Tratamiento , Vacio , Cicatrización de Heridas , Adulto Joven
10.
Leukemia ; 30(7): 1520-30, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27055871

RESUMEN

T lymphocyte non-Hodgkin's lymphoma (T-NHL) represents an aggressive and largely therapy-resistant subtype of lymphoid malignancies. As deregulated apoptosis is a frequent hallmark of lymphomagenesis, we analyzed gene expression profiles and protein levels of primary human T-NHL samples for various apoptotic regulators. We identified the apoptotic regulator MCL-1 as the only pro-survival BCL-2 family member to be highly expressed throughout all human T-NHL subtypes. Functional validation of pro-survival protein members of the BCL-2 family in two independent T-NHL mouse models identified that the partial loss of Mcl-1 significantly delayed T-NHL development in vivo. Moreover, the inducible reduction of MCL-1 protein levels in lymphoma-burdened mice severely impaired the continued survival of T-NHL cells, increased their susceptibility to chemotherapeutics and delayed lymphoma progression. Lymphoma viability remained unaffected by the genetic deletion or pharmacological inhibition of all alternative BCL-2 family members. Consistent with a therapeutic window for MCL-1 treatment within the context of the whole organism, we observed an only minimal toxicity after systemic heterozygous loss of Mcl-1 in vivo. We conclude that re-activation of mitochondrial apoptosis by blockade of MCL-1 represents a promising therapeutic strategy to treat T-cell lymphoma.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/genética , Apoptosis , Linfoma de Células T/química , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/análisis , Animales , Proteínas Reguladoras de la Apoptosis/análisis , Supervivencia Celular , Resistencia a Antineoplásicos , Perfilación de la Expresión Génica , Humanos , Linfoma de Células T/patología , Ratones , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/antagonistas & inhibidores , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/genética , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/fisiología , Proteínas Proto-Oncogénicas c-bcl-2/genética
11.
Neuroscience ; 310: 51-62, 2015 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-26363149

RESUMEN

Although several studies have suggested the neuroprotective effect of thymosin ß4 (TB4), a major actin-sequestering protein, on the central nervous system, little is understood regarding the action of N-acetyl-serylaspartyl-lysyl-proline (Ac-SDKP), a peptide fragment of TB4 on brain function. Here, we examined neurogenesis-stimulative effect of Ac-SDKP. Intrahippocampal infusion of Ac-SDKP facilitated the generation of new neurons in the hippocampus. Ac-SDKP-treated mouse hippocampus showed an increase in ß-catenin stability with reduction of glycogen synthase kinase-3ß (GSK-3ß) activity. Moreover, inhibition of vascular endothelial growth factor (VEGF) signaling blocked Ac-SDKP-facilitated neural proliferation. Subchronic intrahippocampal infusion of Ac-SDKP also increased spatial memory. Taken together, these data demonstrate that Ac-SDKP functions as a regulator of neural proliferation and indicate that Ac-SDKP may be a therapeutic candidate for diseases characterized by neuronal loss.


Asunto(s)
Hipocampo/efectos de los fármacos , Neurogénesis/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Oligopéptidos/farmacología , Memoria Espacial/efectos de los fármacos , Animales , Recuento de Células , Proliferación Celular/efectos de los fármacos , Proteínas de Dominio Doblecortina , Regulación de la Expresión Génica/efectos de los fármacos , Proteína Ácida Fibrilar de la Glía/metabolismo , Glucógeno Sintasa Quinasa 3/metabolismo , Células HeLa , Humanos , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Proteínas Asociadas a Microtúbulos/metabolismo , Neuropéptidos/metabolismo , Fosfopiruvato Hidratasa/metabolismo , Timosina/metabolismo
12.
Med Phys ; 15(6): 815-24, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3237137

RESUMEN

Nuclear magnetic resonance (NMR) microscopy with 4-microns resolution, a step closer to the 1-micron resolution with which in vivo cellular imaging would be possible is described. An analysis of the ultimate resolution and voxel size dependent signal-to-noise ratio (SNR) in NMR microscopy is presented and experimentally verified. For microscopic scale objects (less than 1-mm diameter), the SNR based on the geometrical scale factor(s) is found to be proportional to sn where n less than 2, rather than n = 3 as previously supposed. This comes about because of a drastic reduction in sample noise coupled with a significant sensitivity gain realized in small diameter radiofrequency coils. A new pulse sequence which reduces both diffusion dependent resolution degradation and signal attenuation is presented. The selection of optimal bandwidth and acquisition time for maximal SNR is discussed. Experimental results obtained on both a 2.0-T whole-body system and a 7.0-T small bore system adapted for microscopy indicate the potentials of 4-microns resolution microscopy with the existing magnets.


Asunto(s)
Espectroscopía de Resonancia Magnética/métodos , Modelos Teóricos , Animales , Embrión de Mamíferos/anatomía & histología , Espectroscopía de Resonancia Magnética/instrumentación , Matemática , Microscopía/instrumentación , Microscopía/métodos , Ratas
13.
Phytochemistry ; 53(8): 1001-3, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10820820

RESUMEN

Two glycosides, tetracentronsides A and B, were isolated from the stem bark of Tetracentron sinense Oliv., along with ten known compounds, beta-sitosterol, lupeol, betulinic acid, oleanolic acid, vanillic aldehyde, vanillic acid, maslinic acid, huazhongilexin, daucosterol and catechin. On the basis of spectral and chemical evidence, tetracentronside A and B were identified as 3,4,5-trimethoxyphenyl-O-6'-O-vanilloyl-beta-D-glucopyranoside and (8R, 8'R) 9-beta-D-glucopyranosyl dihydrocubebin, respectively.


Asunto(s)
Glicósidos/aislamiento & purificación , Magnoliopsida/química , Glicósidos/química , Espectroscopía de Resonancia Magnética , Tallos de la Planta/química
14.
Magn Reson Imaging ; 15(7): 815-22, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9309612

RESUMEN

Acoustic or sound noise due to gradient pulsing has been one of the problems in magnetic resonance imaging (MRI), both in patient scanning as well as in many areas of psychiatric and neuroscience research such as functional MRI. Our recent observations in functional MRI for the visual and motor cortex show very different results with sound noise in comparison with the results obtained without sound noise. Although a number of ideas have been suggested in the literature about the possible elimination or reduction of sound noise, progress has been slow due to the basic role of gradient pulsing in MR imaging. Before we tackle the sound-noise-reduction problem, we believe that a systematic study of sound or acoustic noise behavior will provide important information for future endeavors in this area of research in MRI systems, in both commercial and research systems. Therefore, we report on some typical behavior of sound noise observed from MRI scanners and the analyses of their characteristics. Data are obtained both from a commercial MRI scanner (GE Signa 1.5-T EPI system) as well as a research-type MRI scanner (KAIS 2.0-T) developed at a university laboratory setting.


Asunto(s)
Imagen por Resonancia Magnética , Ruido , Fenómenos Físicos , Física , Procesamiento de Señales Asistido por Computador
16.
Chemosphere ; 43(4-7): 701-7, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11372855

RESUMEN

This study was carried out to examine the formation and the emission status of polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDDs/PCDFs) in the flue gases of commercial-scale municipal solid waste (MSW) incinerators, and thus to provide the engineering data for the reduction of PCDDs/PCDFs emitted from MSW incinerators. The formation concentrations of the PCDDs/PCDFs generated at the outlet of waste heat boilers (WHB) were in the range of 1.18-29.61 ng-TEQ/N m3 (average 5.75 ng-TEQ/N m3), while the emission concentrations at the stacks were in the range of 0.026-4.548 ng-TEQ/N m3 (average 0.924 ng-TEQ/N m3). Two major 2,3,7,8-substituted congeners were 2,3,4,7,8-PeCDF and 2,3,4,6,7,8-HxCDF, and their concentrations were up to 50% and 64% of total TEQ values at the outlet of WHB and the stack, respectively. From the results of multi-regression analysis, the formation concentration of PCDDs/PCDFs could be predicted as follows with the correlation factor of r2 = 0.962: PCDDs/PCDFs (ng-TEQ/N m3) = 3.036 (Cl) + 0.094 (T1) - 0.472 (Combustibles) + 0.059 (CO) - 0.039 (THC) - 3.366 (H) + 22.157, where T1 (degrees C) is the temperature at the outlet of the WHB. Cl, Combustibles and H are given as percentages and the others are in parts per million.


Asunto(s)
Contaminantes Atmosféricos/análisis , Benzofuranos/análisis , Dibenzodioxinas Policloradas/análisis , Eliminación de Residuos , Contaminantes del Suelo/análisis , Dibenzofuranos Policlorados , Monitoreo del Ambiente , Gases , Incineración , Corea (Geográfico) , Dibenzodioxinas Policloradas/análogos & derivados , Análisis de Regresión , Temperatura
17.
Chemosphere ; 43(4-7): 773-6, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11372864

RESUMEN

Removal efficiencies of polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDDs/PCDFs) by air pollution control devices (APCDs) in the commercial-scale municipal solid waste (MSW) incinerators with a capacity of above 200 ton/day were evaluated. The removal efficiencies of PCDDs/PCDFs were up to 95% when the activated carbon (AC) was injected in front of electrostatic precipitator (EP). Spray dryer absorber/bag filter (SDA/BF) had high removal efficiency (99%)) of PCDDs/PCDFs when a mixture of lime and AC was sprayed into the SDA. When the AC was not added in scrubbing solution, the whole congeners of PCDDs/PCDFs were enriched in the wet scrubber (WS) with negative removal efficiencies of -25% to -5731%. Discharge of PCDDs/PCDFs was decreased with increasing the proportions of AC added in scrubbing solution. Selective catalytic reduction (SCR) system had the removal efficiencies of up to 93% during the test operation.


Asunto(s)
Contaminación del Aire/prevención & control , Benzofuranos/análisis , Dibenzodioxinas Policloradas/análisis , Eliminación de Residuos/instrumentación , Contaminantes del Suelo/análisis , Carbono/química , Dibenzofuranos Policlorados , Monitoreo del Ambiente , Filtración , Incineración , Dibenzodioxinas Policloradas/análogos & derivados , Eliminación de Residuos/métodos , Electricidad Estática
18.
Med Biol Eng Comput ; 41(5): 516-8, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-14572000

RESUMEN

The performance of the stimulation coil in a magnetic nerve stimulator can be improved by attaching a ferromagnetic structure to the coil. This reduces heat generation at the coil and increases magnetic field strength for a given unit of current. Some technical aspects of the design of a stimulation coil with a ferromagnetic structure have been studied. Finite element method analysis results are presented for the effect of size, depth and magnetic saturation of the ferromagnetic structure on the stimulation coil performance. The experimental results show that the stimulation coil performance is improved by up to 40% by the attaching of a ferromagnetic structure on the coil.


Asunto(s)
Estimulación Eléctrica/instrumentación , Campos Electromagnéticos , Diseño de Equipo , Compuestos Férricos , Análisis de Elementos Finitos , Humanos
19.
Yao Xue Xue Bao ; 26(1): 37-41, 1991.
Artículo en Zh | MEDLINE | ID: mdl-1887792

RESUMEN

Two new highly oxygenated iridoids, named lamiophlomiol A and B, were isolated from an alcohol extract of the roots of Lamiophlomis rotata (Labiatea) by silica gel G column chromatography. Lamiophlomiol A and B are two epimers. Their structures were elucidated to be Ia and Ib with spectroscopic and chemical analysis.


Asunto(s)
Medicamentos Herbarios Chinos/química , Compuestos Epoxi/aislamiento & purificación , Piranos/aislamiento & purificación , Compuestos Epoxi/química , Piranos/química , Estereoisomerismo
20.
Yao Xue Xue Bao ; 27(3): 204-6, 1992.
Artículo en Zh | MEDLINE | ID: mdl-1414386

RESUMEN

A new highly oxygenated iridoid, lamiophlomiol C isolated from the alcohol soluble fraction of the roots of Lamiophlomis rotata (Labiatae), was shown to have the molecular formula C11H14O7. On the basis of UV, IR, MS and NMR spectroscopic data, particularly X-ray crystallographlic analysis, structure I has been assigned to this iridoid.


Asunto(s)
Medicamentos Herbarios Chinos/química , Piranos/química , Conformación Molecular , Piranos/aislamiento & purificación , Difracción de Rayos X
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