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1.
Chemosphere ; 46(9-10): 1255-62, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12002448

RESUMEN

The potential of fly ash to dechlorinate and destroy PCDD, PCDF and PCB was tested under oxygen deficient conditions in the laboratory. Specifically, two types of fly ash were compared, originating either from a fluidized bed incinerator using Ca(OH)2 spray (FA1), or a stoker incinerator without Ca(OH)2 impact (FA2). Results from the present study indicate that on FA2 type fly ash, the degradation processes of OCDD, OCDF and D10CB occurred primarily via dechlorination/hydrogenation up to temperature settings of 340 degrees C. In contrast, FAI type fly ash was found to effect both dechlorination and destruction of these compounds already at temperature settings of 260 degrees C. The dechlorination velocity of PCDD and PCDF did not differ significantly. However, the first dechlorination step of OCDF in the 1,9-position occurred faster compared to the first dechlorination step of OCDD. The isomer pattern resulting from the dechlorination processes was quite similar on both FAI and FA2, indicating that differences in alkalinity or elemental composition of the two types of fly ashes do not have a significant influence on the position of dechlorination. PCDD and PCDF dechlorination of the 2,3,7,8-positions was not favoured over dechlorination of the 1,4.6,9-positions on either type of fly ash. In contrast, dechlorination of PCB occurred predominantly on the toxicological relevant 3- and 4-positions. The dechlorination/destruction processes were completed on both types of fly ash at 380 degrees C within one hour, which correlates well with results obtained from actual plant operation practices.


Asunto(s)
Benzofuranos/análisis , Contaminantes Ambientales/análisis , Bifenilos Policlorados/análisis , Dibenzodioxinas Policloradas/análogos & derivados , Dibenzodioxinas Policloradas/análisis , Eliminación de Residuos , Contaminantes del Suelo/análisis , Contaminación del Aire/prevención & control , Benzofuranos/química , Dibenzofuranos Policlorados , Monitoreo del Ambiente , Hipoxia , Incineración , Bifenilos Policlorados/química , Dibenzodioxinas Policloradas/química , Temperatura
2.
J Clin Pharmacol ; 40(3): 284-9, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10709157

RESUMEN

The authors investigated whether theophylline metabolism is decreased in asthmatic patients and what condition may be related to its reduction. Fifty-two children with asthma were given 15 mg/kg/day aminophylline intravenously at a constant rate. Blood and spot urine samples were collected at 24 hours, 48 hours, and 72 hours after beginning infusion. The ratio of plasma theophylline concentration at 72 hours to that at 24 hours (C72h/C24h) varied from 0.42 to 1.51 (average 0.894). Plasma theophylline concentration of patients with lower C72h/C24h than average reduced significantly, while the concentration of those with higher C72h/C24h remained unchanged. The urinary ratio of the sum of the metabolites to theophylline was significantly increased in the patients with the lower ratio. Among the demographic characteristics examined, significant difference was found only in the incidence of patients with C-reactive protein (CRP) of 0.5 mg/dl or greater or patients with a fever of 37.5 degrees C or greater when admitted. Acute febrile illness accompanied by increased CRP level may affect theophylline metabolism.


Asunto(s)
Asma/metabolismo , Broncodilatadores/metabolismo , Proteína C-Reactiva/metabolismo , Fiebre/inducido químicamente , Teofilina/metabolismo , Adolescente , Asma/tratamiento farmacológico , Broncodilatadores/sangre , Broncodilatadores/orina , Niño , Preescolar , Femenino , Humanos , Lactante , Infusiones Intravenosas , Masculino , Teofilina/efectos adversos , Teofilina/sangre , Teofilina/orina
3.
Am J Gastroenterol ; 93(11): 2167-71, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9820391

RESUMEN

OBJECTIVE: We undertook to evaluate the therapeutic effects of radiotherapy in patients with bone metastases from hepatocellular carcinoma (HCC), identify prognostic factors, and find an optimum radiation schedule. METHODS: We retrospectively analyzed the clinical records of 57 patients (99 sites) with painful bone metastases from HCC from December 1978 to March 1997. Their ages ranged from 51 to 82 yr (mean, 62 yr), and the male:female ratio was 49:8. Among them, there were nine patients (16%) with metastases to other organs. Twenty patients (35%) had a solitary bone metastasis and 37 (65%) had multiple bone metastases. The total radiation dose ranged from 20 to 65 Gy (mean, 43 Gy) and that of the Time, Dose, and Fractionation Factor (TDF) values (per explanation given in text) ranged from 35.2 to 118.2 (mean, 73.2). RESULTS: Pain relief was obtained for 83.8% (83/99) of bone metastases from HCC. Those with a TDF value of > or = 77 (a TDF value of 77 is nearly equal to 48 Gy administered in fractions of 2 Gy each daily or 39 Gy administered in fractions of 3 Gy each daily), responded better than those with a TDF value of < 77 (p < 0.05). Overall, the median survival time from the start of radiotherapy was 179 days (6 months). Patients with a solitary bone metastasis and those without metastases to other organs had a better prognosis (p < 0.05 for both subgroups). CONCLUSIONS: Radiation therapy was effective for bone metastases from HCC, especially for those treated with a TDF value of > or = 77.


Asunto(s)
Neoplasias Óseas/radioterapia , Neoplasias Óseas/secundario , Carcinoma Hepatocelular/radioterapia , Carcinoma Hepatocelular/secundario , Neoplasias Hepáticas/patología , Anciano , Anciano de 80 o más Años , Neoplasias Óseas/mortalidad , Carcinoma Hepatocelular/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dosificación Radioterapéutica , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento
4.
J Gastroenterol ; 32(5): 672-6, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9349996

RESUMEN

Hepatic actinomycosis is rare. We report an 86-year-old Japanese man with a 3-day history of high fever and anorexia who had an actinomycotic liver abscess complicated by disseminated intravascular coagulation (DIC). A definitive diagnosis was made when an Actinomyces species was cultured from aspirated pus. The clinical course was satisfactory. Treatment included prompt percutaneous drainage coupled with long-term intravenous administration of high-dose minocycline and piperacillin, combined with therapy for DIC. We reviewed 11 cases in Japan of Actinomyces involving the liver, including the case reported here. In most patients, there were no predisposing factors. Common symptoms and laboratory findings included fever, abdominal pain, leukocytosis, and elevated C-reactive protein. In 6 of the 11 patients a partial hepatectomy was performed because hepatic tumor was suspected. Five patients presented with a liver abscess. Hepatic actinomycosis should be considered in the differential diagnoses of pyogenic liver abscess and space-occupying lesions of the liver.


Asunto(s)
Actinomicosis/etiología , Absceso Hepático/microbiología , Actinomyces/aislamiento & purificación , Actinomicosis/diagnóstico , Actinomicosis/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Coagulación Intravascular Diseminada/tratamiento farmacológico , Coagulación Intravascular Diseminada/microbiología , Quimioterapia Combinada/administración & dosificación , Quimioterapia Combinada/uso terapéutico , Femenino , Estudios de Seguimiento , Humanos , Infusiones Intravenosas , Absceso Hepático/diagnóstico , Absceso Hepático/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Minociclina/administración & dosificación , Minociclina/uso terapéutico , Penicilinas/administración & dosificación , Penicilinas/uso terapéutico , Piperacilina/administración & dosificación , Piperacilina/uso terapéutico , Tomografía Computarizada por Rayos X
5.
Neurosurgery ; 40(4): 773-80; discussion 780-1, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9092851

RESUMEN

OBJECTIVE: To study how neuronal cells are affected by development of chronic cerebral vasospasm after subarachnoid hemorrhage (SAH), the changes in neuronal metabolites during development of vasospasm were evaluated by in vivo localized proton magnetic resonance spectroscopy (MRS) in primates. METHODS: SAH was produced by introduction of a blood clot around the right middle cerebral artery and the right side of the circle of Willis. MRS experiments were performed before SAH and on Days 7 and 14 after SAH. Multislice magnetic resonance images were obtained to locate the volume of interest (1.0 cm3) in the bilateral parietal regions. The peak areas for choline compounds, the sum of creatine and phosphocreatine, and N-acetyl-aspartate were calculated. RESULTS: Angiograms revealed approximately 50% reduction of vessel caliber for the right main cerebral arteries on Day 7. Magnetic resonance imaging revealed no apparent cerebral infarction, even in the spasm-side hemisphere. MRS revealed a significant (P < 0.05) reduction of the N-acetyl-aspartate/creatine and phosphocreatine ratio on Days 7 and 14 and a significant increase in the choline/creatine and phosphocreatine ratio on Day 7, in the spasm-side parietal region. In the sham-operated animals, there were no significant changes in these ratios in the bilateral parietal region on Days 7 and 14 after the operation. CONCLUSION: The results suggested that the development of cerebral vasospasm after SAH caused ischemic injury in a subpopulation of neuronal cells, even when no apparent cerebral infarction was shown. Proton MRS may be useful to evaluate how neuronal cells are affected by the ischemic insult during development of vasospasm in clinical situations.


Asunto(s)
Encéfalo/metabolismo , Ataque Isquémico Transitorio/metabolismo , Imagen por Resonancia Magnética/métodos , Animales , Ácido Aspártico/análogos & derivados , Ácido Aspártico/análisis , Encéfalo/diagnóstico por imagen , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/etiología , Isquemia Encefálica/metabolismo , Angiografía Cerebral , Circulación Cerebrovascular , Colina/análisis , Enfermedad Crónica , Trastornos del Conocimiento/etiología , Creatinina/análisis , Metabolismo Energético , Femenino , Ataque Isquémico Transitorio/diagnóstico por imagen , Ataque Isquémico Transitorio/etiología , Macaca fascicularis , Neuronas/metabolismo , Neuronas/patología , Fosfocreatina/análisis , Hemorragia Subaracnoidea/complicaciones , Hemorragia Subaracnoidea/metabolismo
6.
Am J Gastroenterol ; 91(4): 777-9, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8677948

RESUMEN

The protein C anticoagulant pathway is an important downregulating mechanism of the blood coagulation cascade. We report a 47-yr-old male with Budd-Chiari syndrome and occlusion of the inferior vena cava. His plasma protein C antigen level was decreased to 42%, and its activity was 34%. Other coagulable factors were normal. Protein C deficiency should be considered a possible etiological factor of the Budd-Chiari syndrome.


Asunto(s)
Síndrome de Budd-Chiari/etiología , Deficiencia de Proteína C , Alcoholismo/complicaciones , Síndrome de Budd-Chiari/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Trombosis/diagnóstico , Trombosis/etiología , Vena Cava Inferior
7.
J Clin Pharmacol ; 34(1): 52-9, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8132852

RESUMEN

The pharmacokinetics of N4-behenoyl-1-beta-D-arabinofuranosylcytosine (BHAC), a lipophilic antitumor analog of 1-beta-D-arabinofuranosylcytosine (ara-C), was investigated, by assay of plasma and leukemic cells of ten acute leukemic patients receiving 60-minute intravenous (IV) infusion of 700 mg/m2 BHAC, for BHAC and 1-beta-D-arabinofuranosylcytosine 5'-triphosphate (ara-CTP) by high-performance liquid chromatography, ara-C by radioimmunoassay, and 1-beta-D-arabinofuranosyluracil (ara-U) by gas chromatography-mass fragmentography. The plasma concentration of BHAC reached a maximum (173.4 +/- 75.3 micrograms/mL) at the end of the infusion and then declined in a biphasic pattern with an initial-phase half-life (t1/2 alpha) of 1.00 +/- .36 hours and a second-phase half-life (t1/2 beta) of 4.28 +/- 2.35 hours. That of ara-C similarly reached a maximum (102.2 +/- 39.9 mg/mL) at the end of the infusion and then declined with t1/2 alpha of 1.37 +/- 1.11 hours and t1/2 beta of 11.2 +/- 4.31 hours. Intracellular ara-CTP concentration increased in a linear-accumulation manner for the first 4 hours after the infusion, reached a maximum of .081 +/- .112 micrograms/10(7) cells at approximately 7 hours, and then declined very slowly in accordance with a one-compartment model with t1/2 of 13.56 +/- 9.62 hours.


Asunto(s)
Antineoplásicos/farmacocinética , Citarabina/análogos & derivados , Leucemia Mieloide Aguda/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Antineoplásicos/administración & dosificación , Antineoplásicos/sangre , Arabinofuranosil Uracilo/sangre , Cromatografía Líquida de Alta Presión , Citarabina/administración & dosificación , Citarabina/sangre , Citarabina/farmacocinética , Semivida , Humanos , Infusiones Intravenosas , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico
9.
Kansenshogaku Zasshi ; 63(1): 27-34, 1989 Jan.
Artículo en Japonés | MEDLINE | ID: mdl-2501420

RESUMEN

The immune response after HB vaccination (20 micrograms, 3 times) was investigated in 15 alcoholics and the immunological background was also studied before the vaccination in some of these cases. Anti-HBs was detected in only 8 (53.3%) out of 15 vaccinated alcoholics and the anti-HBs titers of these 8 responders were less than 16 cut off index at the last observation. Immunologically, peripheral lymphocyte count and/or the OKT4/OKT8 ratio of lymphocytes in 2 alcoholics (non-responders to vaccination) were lower than those in a control case (good responder). But, there were no differences in serum anti-HAV, anti-EBNA positive rates, immunoglobulin levels and blastogenesis by PHA, Con-A between responders and non-responders. These data suggest that poor response to HB vaccination is probably due to an impaired cellular immunity in alcoholics and the necessity of re-vaccination for no or low responders should be considered.


Asunto(s)
Alcoholismo/inmunología , Hepatitis B/prevención & control , Vacunación , Vacunas contra Hepatitis Viral/inmunología , Adulto , Anticuerpos contra la Hepatitis B/biosíntesis , Humanos , Inmunidad Celular , Masculino , Persona de Mediana Edad
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