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1.
J Viral Hepat ; 20(8): 524-9, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23808990

RESUMEN

Sustained virologic response (SVR) is the standard measure for evaluating response to therapy in patients with chronic hepatitis C (CHC). The aim of this study was to prospectively assess the durability of SVR in the pivotal studies of peginterferon (PEG-IFN) α-2b or IFN α-2b. We conducted two phase 3b long-term follow-up studies of patients previously treated for CHC in eight prospective randomized studies of IFN α-2b and/or PEG-IFN α-2b. Patients who achieved SVR [undetectable hepatitis C virus (HCV) RNA 24 weeks after completion of treatment] were eligible for inclusion in these follow-up studies. In total, 636 patients with SVR following treatment with IFN α-2b and 366 with SVR following treatment with PEG-IFN α-2b were enrolled. Definite relapse (quantifiable serum HCV RNA with no subsequent undetectable HCV RNA) was reported in six patients treated with IFN α-2b and three patients treated with PEG-IFN α-2b. Based on these relapses, the point estimate for the likelihood of maintaining response after 5 years was 99.2% [95% confidence interval (CI), 98.1-99.7%] for IFN α-2b and 99.4% (95% CI, 97.7-99.9%) for PEG-IFN α-2b. Successful treatment of hepatitis C with PEG-IFN α-2b or IFN α-2b leads to clinical cure of hepatitis C in the vast majority of cases.


Asunto(s)
Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Polietilenglicoles/uso terapéutico , Ribavirina/uso terapéutico , Quimioterapia Combinada , Estudios de Seguimiento , Hepacivirus/aislamiento & purificación , Humanos , Interferón alfa-2 , Estudios Prospectivos , ARN Viral/sangre , Proteínas Recombinantes/uso terapéutico , Recurrencia , Resultado del Tratamiento
2.
Aliment Pharmacol Ther ; 31(7): 719-34, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20070284

RESUMEN

BACKGROUND: Primary analysis of the Hepatitis C Antiviral Long-Term Treatment against Cirrhosis (HALT-C) Trial showed long-term peginterferon therapy did not reduce complications in patients with chronic hepatitis C and advanced fibrosis or cirrhosis. AIM: To assess the effects of long-term peginterferon therapy and disease progression on health-related quality of life (HRQOL), symptoms and sexual health in HALT-C patients. METHODS: A total of 517 HALT-C patients received peginterferon alfa-2a (90 microg/week); 532 received no additional treatment for 3.5 years. Patients were followed up for outcomes of death, hepatocellular carcinoma and hepatic decompensation. Sexual health, SF-36 scores and symptoms were serially assessed by repeated-measures analyses of covariance. RESULTS: Patients with cirrhosis (n = 427) reported lower general well-being and more fatigue (P < 0.001) than patients with fibrosis (n = 622). Physical scores declined significantly over time, independent of treatment, and patients with cirrhosis reported lower scores. Vitality scores were lower in those with cirrhosis, and treated patients experienced a greater decline over time than untreated patients; HRQOL rebounded after treatment ended. Patients with a clinical outcome had significantly greater declines in all SF-36 and symptom scores. Among men, Sexual Health scores were significantly worse in treated patients and in those with a clinical outcome. CONCLUSION: Clinical progression of chronic hepatitis C and maintenance peginterferon therapy led to worsening of symptoms, HRQOL and, in men, sexual health in a large patient cohort followed up over 4 years (NCT00006164).


Asunto(s)
Antivirales/administración & dosificación , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/administración & dosificación , Cirrosis Hepática/tratamiento farmacológico , Polietilenglicoles/administración & dosificación , Calidad de Vida , Conducta Sexual/efectos de los fármacos , Adulto , Fatiga/complicaciones , Fatiga/psicología , Femenino , Hepatitis C Crónica/psicología , Hepatitis C Crónica/virología , Humanos , Interferón alfa-2 , Cirrosis Hepática/psicología , Cirrosis Hepática/virología , Masculino , Persona de Mediana Edad , Calidad de Vida/psicología , Proteínas Recombinantes , Conducta Sexual/psicología , Factores Socioeconómicos
3.
Aliment Pharmacol Ther ; 29(5): 589-601, 2009 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-19053983

RESUMEN

BACKGROUND: The impact of virologic response on hepatic function has not been previously defined. AIM: To determine the relationships of quantitative liver function tests (QLFTs) with virological responses to peginterferon (PEG) +/- ribavirin (RBV) in patients with chronic hepatitis C and to use serial QLFTs to define the spectrum of hepatic improvement after sustained virological response (SVR). METHODS: Participants (n = 232) were enrolled in the Hepatitis C Antiviral Long-term Treatment against Cirrhosis (HALT-C) Trial, had failed prior therapy, had bridging fibrosis or cirrhosis and were retreated with PEG/RBV. All 232 patients had baseline QLFTs; 24 patients with SVR and 68 nonresponders had serial QLFTs. Lidocaine, [24-(13)C]cholate, galactose and (99m)Tc-sulfur colloid were administered intravenously; [2,2,4,2-(2)H]cholate, [1-(13)C]methionine, caffeine and antipyrine were administered orally. Clearances (Cl), breath (13)CO(2), monoethylglycylxylidide (MEGX), perfused hepatic mass (PHM) and liver volume were measured. RESULTS: Rates of SVR were 18-26% in patients with good function by QLFTs, but < or =6% in patients with poor function. Hepatic metabolism, measured by caffeine k(elim) (P = 0.02), antipyrine k(elim) (P = 0.05) and antipyrine Cl (P = 0.02) and the portal circulation, measured by cholate Cl(oral) (P = 0.0002) and cholate shunt (P = 0.0003) and PHM (P = 0.03) improved after SVR. CONCLUSION: Hepatic dysfunction impairs the virological response to PEG/RBV. SVR improves hepatic metabolism, the portal circulation and PHM.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C Crónica/tratamiento farmacológico , Interferones/uso terapéutico , Adulto , Relación Dosis-Respuesta a Droga , Femenino , Hepatitis C Crónica/fisiopatología , Hepatitis C Crónica/virología , Humanos , Pruebas de Función Hepática/métodos , Masculino , Persona de Mediana Edad , Ribavirina , Estadística como Asunto
4.
Appl Opt ; 47(22): 4085-93, 2008 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-18670566

RESUMEN

When lidar pulses travel through a short path that includes a relatively high concentration of aerosols, scattering phenomena can alter the power and temporal properties of the pulses significantly, causing undesirable effects in the received pulse. In many applications the design of the lidar transmitter and receiver must consider adverse environmental aerosol conditions to ensure the desired performance. We present an analytical model of lidar system operation when the optical path includes aerosols for use in support of instrument design, simulations, and system evaluation. The model considers an optical path terminated with a solid object, although it can also be applied, with minor modifications, to cases where the expected backscatter occurs from nonsolid objects. The optical path aerosols are characterized by their attenuation and backscatter coefficients derived by the Mie theory from the concentration and particle size distribution of the aerosol. Other inputs include the lidar system parameters and instrument response function, and the model output is the time-resolved received pulse. The model is demonstrated and experimentally validated with military fog oil smoke for short ranges (several meters). The results are obtained with a lidar system operating at a wavelength of 0.905 microm within and outside the aerosol. The model goodness of fit is evaluated using the statistical coefficient of determination whose value ranged from 0.88 to 0.99 in this study.


Asunto(s)
Aerosoles/análisis , Aerosoles/química , Algoritmos , Artefactos , Rayos Láser , Modelos Teóricos , Radar , Simulación por Computador , Reproducibilidad de los Resultados , Dispersión de Radiación , Sensibilidad y Especificidad
5.
Aliment Pharmacol Ther ; 27(9): 798-809, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18266997

RESUMEN

BACKGROUND: The spectrum of functional impairment in patients with compensated chronic hepatitis C is incompletely defined. AIM: To define hepatic impairment by quantitative tests (quantitative liver function tests) and correlate results with disease severity in patients with chronic hepatitis C. METHODS: We studied 285 adult patients with chronic hepatitis C prior to treatment in the Hepatitis C Anti-viral Long-term Treatment against Cirrhosis Trial; 171 had Ishak fibrosis stages 2-4 (fibrosis) and 114 had stage 5 or 6 (cirrhosis). None had had clinical decompensation. A battery of 12 quantitative liver function test assessed the spectrum of hepatic microsomal, mitochondrial and cytosolic functions, and hepatic and portal blood flow. RESULTS: Twenty-six to 63% of patients with fibrosis and 45-89% with cirrhosis had hepatic impairment by quantitative liver function test; patients with cirrhosis had the greatest impairment (P-value ranging from 0.15 to <0.0001). Cholate Cl(oral), cholate shunt and perfused hepatic mass correlated with cirrhosis, stage of fibrosis (r = -0.51, +0.49, -0.51), varices and variceal size (r = -0.39, +0.36, -0.41). PHM < 95 and cholate shunt >35% identified 91% of patients with medium- or large-sized varices. CONCLUSIONS: Hepatic impairment is common in compensated patients with fibrosis or cirrhosis because of chronic hepatitis C. Cholate shunt, and cholate Cl(oral) and perfused hepatic mass, identify patients at risk for cirrhosis or varices.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C Crónica/fisiopatología , Cirrosis Hepática/fisiopatología , Pruebas de Función Hepática/métodos , Adulto , Femenino , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Cirrosis Hepática/etiología , Masculino , Persona de Mediana Edad , Estadística como Asunto
6.
Aliment Pharmacol Ther ; 26(3): 401-10, 2007 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-17635375

RESUMEN

BACKGROUND: Measurement of portal inflow and portal-systemic shunt using cholate clearances could be useful in monitoring patients with liver disease. AIM: To examine relationships of cholate clearances and shunt to cirrhosis and varices and to define minimal sampling requirements. METHODS: Five hundred forty-eight studies were performed in 282 patients enrolled in the Hepatitis C Antiviral Long-term Treatment to prevent Cirrhosis (HALT-C) trial. Stable, non-radioactive isotopes of cholate were administered intravenously and orally, clearances (Cl(iv) and Cl(oral)) were calculated from [dose/area under curve (AUC)] and cholate shunt from [(AUC(oral):AUC(iv)) x (Dose(iv):Dose(oral)) x 100%]. RESULTS: Cholate Cl(oral) and cholate shunt correlated with prevalences of both cirrhosis and varices (P < 0.0001 for all). Peripheral venous sampling at 5, 20, 45, 60 and 90 min defined the minimal model. Linear regression of cholate shunt determined from five points within 90 min vs. the standard method of 14 points over 3 h yielded slope of 1.0 and intercept 0.5% (r(2) = 0.98, P < 0.0001). Results were identical in the 189 validation studies (slope 1.0, intercept 0.5%, r(2) = 0.99, P < 0.0001). CONCLUSIONS: Cholate Cl(oral) and cholate shunt may be useful in monitoring patients with liver disease. The 5-point model enhances application of cholate Cl(oral) and cholate shunt in the non-invasive assessment of the portal circulation.


Asunto(s)
Colatos/uso terapéutico , Hepatitis C Crónica/tratamiento farmacológico , Cirrosis Hepática/tratamiento farmacológico , Derivación Portosistémica Quirúrgica/métodos , Colatos/administración & dosificación , Hepatitis C Crónica/complicaciones , Humanos , Cirrosis Hepática/etiología , Pruebas de Función Hepática/métodos
7.
J Viral Hepat ; 13(4): 242-9, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16611190

RESUMEN

In previous hepatitis C virus (HCV) treatment studies, Black patients not only had a lower sustained viral response (SVR) rate to interferon and ribavirin (RBV) than non-Black patients but also a higher frequency of HCV genotype 1 (GT-1) infection. The aim of this community-based study was to determine whether Black patients have a lower SVR rate independent of genotype. We prospectively enrolled 785 patients (24.8% Black, 71.5% White, 3.7% others) who received interferon alpha-2b 3 MU three times weekly + RBV 1000-1200 mg/day for 24 weeks (GT-2/3) or 48 weeks (GT-1). Black patients were more commonly infected with GT-1 (86.8%vs 64.8%, P < 0.001) and less frequently had an SVR compared with non-Black patients (8.4%vs 21.6%, P < 0.001). Within GT-1, Black patients had a lower SVR rate than non-Black patients (6.1%vs 14.1%, P = 0.004) but not within GT-2/3 (50.0%vs 36.5%, P = 0.47). Black patients had lower baseline haemoglobin levels (14.8 vs 15.3 g/dL, P < 0.001) and neutrophil counts (2900 vs 4100/mm(3), P < 0.001) and required more frequent dose reductions of RBV (29.8%vs 18.5%, P < 0.001) and interferon (4.7%vs 1.6%, P = 0.012). However, dose reductions were not associated with lower SVR rates while early treatment discontinuations were (2.9%vs 25.7%, P < 0.001). Independent predictors of SVR were GT-1 [odds ratio (OR) 0.33; 95% confidence interval (CI) 0.20-0.55; P < 0.001], Black race (OR 0.45; 95% CI 0.22-0.93; P = 0.030), and advanced fibrosis, stages 3 + 4 (OR 0.53; 95% CI 0.31-0.92; P = 0.023). In conclusion, Black patients infected with HCV GT-1 (but not GT-2/3) have a lower SVR rate than non-Black patients. This is not explained by their lower baseline haemoglobin levels and neutrophil counts that lead to higher rates of ribavirin and interferon dose reductions.


Asunto(s)
Antivirales/administración & dosificación , Población Negra , Hepacivirus/genética , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/administración & dosificación , Ribavirina/administración & dosificación , Alanina Transaminasa/sangre , Antivirales/efectos adversos , Biopsia , Relación Dosis-Respuesta a Droga , Femenino , Genotipo , Hepatitis C Crónica/sangre , Hepatitis C Crónica/virología , Humanos , Interferón-alfa/efectos adversos , Cirrosis Hepática/patología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Prospectivos , ARN Viral/sangre , Ribavirina/efectos adversos , Población Blanca
8.
J Viral Hepat ; 8(6): 414-20, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11703572

RESUMEN

In patients with chronic hepatitis C, 48 weeks of therapy with interferon (IFN) plus ribavirin results in a sustained virologic response of 40%. Preliminary analysis suggests that measuring HCV RNA at week 24, rather than week 12, might provide the best prediction of treatment response. To assess the clinical utility of serum HCV RNA determinations at different times during therapy as a predictor of a sustained virologic response we evaluated 912 treatment-naïve patients. Patients were randomized to receive IFN-alpha2b, 3 million units (MU) three times weekly (tiw), for 24 or 48 weeks with either ribavirin or placebo, and then followed for 24 weeks. Serum HCV RNA was measured at weeks 4 and 12 in patients treated for 24 weeks; at 4, 12, and 24 weeks during therapy in those treated for 48 weeks, and week 24 post-therapy in all patients. Sustained response was defined as loss of serum HCV RNA at week 24 follow-up. Other patients were considered virologic nonresponders. For patients receiving 48 weeks of combination therapy, detectable serum HCV RNA at week 24 predicted nonresponse (positive predictive value) in 99% of patients compared to 89% at week 12. In patients treated for 24 weeks, testing at week 12 was more predictive of nonresponse than testing at week 4 in the combination-therapy group but not in the monotherapy group. Hence, for combination therapy, testing for serum HCV RNA as a predictor of nonresponse is most accurate at week 24 of therapy; a positive test correctly identified 99% of nonresponders.


Asunto(s)
Antivirales/uso terapéutico , Hepacivirus/genética , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/virología , Interferón-alfa/uso terapéutico , ARN Viral/sangre , Ribavirina/uso terapéutico , Alanina Transaminasa/sangre , Enfermedad Crónica , Quimioterapia Combinada , Femenino , Genotipo , Anticuerpos contra la Hepatitis C/sangre , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Factores de Tiempo
9.
Mol Ther ; 4(5): 427-37, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11708879

RESUMEN

Hepatocellular carcinoma is a lethal disease and methods that develop effective cellular-based immunotherapy are needed. We retrovirally transduced non-immunogenic mouse Hepa1-6 hepatoma cells with the gene encoding the membrane form of macrophage colony stimulating factor (mM-CSF). Excess recombinant M-CSF and phagocytosis-inhibiting chemicals blocked macrophage-mediated killing of cloned mM-CSF transfected Hepa1-6 hepatoma cells. Macrophages derived from Hck(-/-)Fgr(-/-) and Lyn(-/-) triple knockout mice, which are incapable of performing phagocytosis, failed to kill the mM-CSF transduced cells. The mM-CSF transfected tumor clones failed to grow when injected into C57BL/6 or C57L/J mice. Splenocytes from these vaccinated mice displayed cytotoxicity against parental Hepa1-6 cells, but not against B16 and CT-26 tumor cells in vitro. Mice that rejected the mM-CSF transfected Hepa1-6 tumor subsequently rejected parental Hepa1-6 cells but not the B16 melanoma cells when rechallenged. Elimination of the CD8+ effector cells by an anti-CD8 antibody and complement treatment prevented the adoptive transfer of anti-Hepa1-6-specific immunity into naive animals. Thus, mM-CSF provides a method of generating effective anti-tumor immune responses by macrophages and cytotoxic T cells against the parental Hepa1-6 cells. Our work suggests that mM-CSF transduced hepatoma cells could be used as a tumor vaccine to stimulate immune responses against hepatocellular carcinoma.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Vacunas contra el Cáncer/inmunología , Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/metabolismo , Factor Estimulante de Colonias de Macrófagos/metabolismo , Animales , Vacunas contra el Cáncer/uso terapéutico , Carcinoma Hepatocelular/genética , Citometría de Flujo , Humanos , Inmunohistoquímica , Interferón gamma/farmacología , Lipopolisacáridos/farmacología , Factor Estimulante de Colonias de Macrófagos/genética , Macrófagos/citología , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Ratones , Ratones Endogámicos C57BL , Trasplante de Neoplasias , Óxido Nítrico/metabolismo , Fagocitosis/efectos de los fármacos , Fagocitosis/inmunología , Linfocitos T Citotóxicos/inmunología , Transfección , Células Tumorales Cultivadas
10.
Hepatology ; 33(2): 455-63, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11172349

RESUMEN

Persons with non-A, non-B hepatitis (cases) identified in 5 transfusion studies in the early 1970s have been followed ever since and compared for outcome with matched, transfused, non-hepatitis controls from the same studies. Previously, we reported no difference in all-cause mortality but slightly increased liver-related mortality between these cohorts after 18 years follow-up. We now present mortality and morbidity data after approximately 25 years of follow-up, restricted to the 3 studies with archived original sera. All-cause mortality was 67% among 222 hepatitis C-related cases and 65% among 377 controls (P = NS). Liver-related mortality was 4.1% and 1.3%, respectively (P =.05). Of 129 living persons with previously diagnosed transfusion-associated hepatitis (TAH), 90 (70%) had proven TAH-C, and 39 (30%), non-A-G hepatitis. Follow-up of the 90 TAH-C cases revealed viremia with chronic hepatitis in 38%, viremia without chronic hepatitis in 39%, anti-HCV without viremia in 17%, and no residual HCV markers in 7%. Thirty-five percent of 20 TAH-C patients biopsied for biochemically defined chronic hepatitis displayed cirrhosis, representing 17% of all those originally HCV-infected. Clinically evident liver disease was observed in 86% with cirrhosis but in only 23% with chronic hepatitis alone. Thirty percent of non-A, non-B hepatitis cases were unrelated to hepatitis viruses A,B,C, and G, suggesting another unidentified agent. In conclusion, all-cause mortality approximately 25 years after acute TAH-C is high but is no different between cases and controls. Liver-related mortality attributable to chronic hepatitis C, though low (<3%), is significantly higher among the cases. Among living patients originally HCV-infected, 23% have spontaneously lost HCV RNA.


Asunto(s)
Hepatitis C/etiología , Hepatitis C/mortalidad , Hepatitis Viral Humana/etiología , Hepatitis Viral Humana/mortalidad , Reacción a la Transfusión , Anciano , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Hepatitis C/complicaciones , Hepatitis C/epidemiología , Hepatitis C/inmunología , Anticuerpos contra la Hepatitis C/análisis , Hepatitis Viral Humana/epidemiología , Hepatitis Viral Humana/inmunología , Humanos , Incidencia , Cirrosis Hepática/virología , Masculino , Persona de Mediana Edad , Análisis de Supervivencia , Viremia/epidemiología
12.
Aviat Space Environ Med ; 71(5): 501-5, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10801004

RESUMEN

BACKGROUND: Acceleration (or G) induced arm pain may develop in centrifuge runs and in flight with low arm position and assisted pressure breathing during G (PBG) in combination with an extended coverage anti-G suit. To decrease this arm pain, pressurized sleeves and gloves were developed. METHODS: Eight subjects who earlier exhibited G-induced arm pain were tested on the centrifuge. The G-exposures consisted of a gradual onset run up to a maximum of +9 G2, rapid onset runs to +3, +4, +5, +6, +7, +8, and +9 Gz and a simulated aerial combat maneuver (SACM) with peaks up to +9 Gz. On separate days, the subjects were tested without the sleeves and gloves, and with the sleeves and gloves pressurized to a maximum of 40, 60, or 80 mmHg at +9 Gz. The subjects reported their left and right arm pain on a subjective rating scale. RESULTS: G-induced arm pain, usually starting above +6 Gz, was often the reason for termination of the G-exposure without the pressurized sleeves and gloves. The pressurized sleeves and gloves significantly (p < 0.001) decreased arm pain, put no significant difference was found among the different pressures used. Heart rate was not different with and without the pressurized sleeves and gloves. CONCLUSIONS: The pressurized sleeves and gloves are an effective method to alleviate and sometimes eliminate G-induced arm pain.


Asunto(s)
Aviación , Hipergravedad , Dolor/prevención & control , Ropa de Protección , Adulto , Medicina Aeroespacial , Brazo/patología , Diseño de Equipo , Humanos , Masculino , Dolor/etiología
13.
Biochemistry ; 37(41): 14437-49, 1998 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-9772170

RESUMEN

The requirement of cytochrome c-550 (PSII-V) in photosystem II (PSII) has been assessed in Synechocystis sp. PCC 6803 containing mutations between Gly-351 and Thr-436 of the loop E domain of the chlorophyll a-binding protein CP47. Six photoautotrophic strains were utilized to compare the effect of removal of either the manganese-stabilizing protein (PSII-O) or PSII-V on PSII activity in vivo. These were a wild-type control; two strains with amino acid deletions, Delta(R384-V392) and Delta(G429-T436); and three carrying specific amino acid substitutions, G351L/T365Q, G351L/E364Q/T365Q, and G351L/E353Q/E355Q/T365Q. The removal of PSII-O prevented the assembly of PSII in Delta(G429-T436) but not in Delta(R384-V392). Neither Delta(G429-T436) nor Delta(R384-V392) could support photoautotrophic growth in the absence of PSII-V. In chloride-limiting conditions, the photoautotrophic growth of Delta(R384-V392) was severely impaired and that of Delta(G429-T436) totally inhibited, and no strains lacking PSII-V could grow in chloride-limiting or calcium-limiting media. Substitutions at Gly-351, Glu-353, Glu-355, and Thr-365 produced phenotypes that were similar to those of the control in the presence or absence of PSII-O and PSII-V, but removal of PSII-O from G351L/E364Q/T365Q produced a significant reduction of assembled PSII centers and an enhanced sensitivity to photoinactivation while removal of PSII-V prevented photoautotrophic growth. The additional mutants E364Q:DeltaPSII-V and E364G:DeltaPSII-V demonstrated that this inhibition was a consequence of the mutation at Glu-364. These results also show that the removal of PSII-V, in vivo, produces phenotypes in the CP47 mutants examined that are either similar or more severe than those resulting from the removal of PSII-O.


Asunto(s)
Grupo Citocromo c/metabolismo , Complejos de Proteína Captadores de Luz , Manganeso/metabolismo , Metaloproteínas/metabolismo , Mutagénesis Sitio-Dirigida , Fragmentos de Péptidos/genética , Proteínas del Complejo del Centro de Reacción Fotosintética/genética , Complejo de Proteína del Fotosistema II , Proteínas/metabolismo , Secuencia de Aminoácidos , Sustitución de Aminoácidos/genética , Calcio , Cloruros , Clorofila/química , Clorofila/genética , Medios de Cultivo Condicionados , Cianobacterias/enzimología , Cianobacterias/genética , Cianobacterias/crecimiento & desarrollo , Grupo Citocromo c/química , Ácido Glutámico/genética , Glutamina/genética , Glicina/genética , Leucina/genética , Datos de Secuencia Molecular , Fragmentos de Péptidos/química , Fotosíntesis/genética , Proteínas del Complejo del Centro de Reacción Fotosintética/química , Proteínas/química , Treonina/genética
14.
J Hepatol ; 28(3): 369-74, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9551672

RESUMEN

BACKGROUND/AIMS: Some studies have suggested that hepatic iron may influence the response to interferon therapy in chronic hepatitis C patients. We conducted this randomized, controlled trial to evaluate the effect of iron depletion on: (1) aminotransferase activity and hepatitis C RNA levels; and (2) response to interferon therapy in 38 patients with elevated alanine aminotransferase levels and who were HCV RNA positive. METHODS: Seventeen patients underwent a 500-ml phlebotomy every 2 weeks until iron deficiency was achieved. Patients were then started on a 6-month course of alpha-interferon 2b (3 mu tiw). Controls were 21 patients who were monitored for a 6- to 8-week period without phlebotomy prior to interferon therapy. Response to interferon was defined as loss of serum HCV RNA by reverse transcriptase-polymerase chain reaction. Serum HCV RNA was quantitated by bDNA technique. RESULTS: Alanine aminotransferase levels decreased in 15/17 patients after phlebotomy. Mean alanine aminotransferase fell from 156.8 to 89.7 U/l (p=0.008). Changes in iron indices and alanine aminotransferase after phlebotomy were not accompanied by changes in HCV RNA levels. In control patients, neither alanine aminotransferase nor HCV RNA levels changed during the observation period. At the end of 24 weeks of interferon therapy, 7/17 phlebotomized patients had a response, compared to 6/21 control patients (p=ns). After 6 months of follow-up, 5/17 phlebotomized patients remained HCV RNA negative, in contrast to only 1/21 controls (p=0.07). CONCLUSIONS: Iron depletion led to a reduction in aminotransferase levels; this was not accompanied by changes in levels of hepatitis C RNA. There may be an improvement in the sustained response to interferon therapy, but this requires confirmation.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C Crónica/sangre , Hepatitis C Crónica/terapia , Interferón-alfa/uso terapéutico , Deficiencias de Hierro , Adulto , Alanina Transaminasa/sangre , Femenino , Hepacivirus/genética , Humanos , Masculino , Persona de Mediana Edad , Flebotomía , Proyectos Piloto , ARN Viral/sangre , Factores de Tiempo
15.
Oncol Nurs Forum ; 22(9): 1401-8, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8539181

RESUMEN

PURPOSE/OBJECTIVES: To determine whether a relationship exists between preferences for involvement in decision making and type of information in patients with cancer. DESIGN: Survey, correlational. SETTING: Community urology clinic in Winnipeg, Manitoba, Canada. SAMPLE: Convenience sample of 57 men (mean age of 71 years). METHODS: Subjects completed a card sort to elicit their preferred role in treatment decision making. A two-part questionnaire measured the type and amount of information preferred. FINDINGS: The majority (57.9%) of men preferred a passive decision-making role. Information on disease advancement, likelihood of cure, and types of treatment available were the three preferred categories of information. Men in the collaborative group and those who wanted their physician to make treatment decisions-only after seriously considering their opinions-also wanted significantly more information in these three categories. Married men ranked self-care information as significantly less important than did single men. Information preferences were similar regardless of preferred decision-making role. CONCLUSIONS: Although the majority of men in this sample wanted their physician to make final treatment decisions, they did want to be informed. Information preferences were similar to other groups of patients with cancer. Future clinical studies are required to determine if providing these men with more information will enable them to assume a more active decision-making role. IMPLICATIONS FOR NURSING PRACTICE: Given the small variance in decision-making and information preferences accounted for by sociodemographic and treatment/disease-related factors, individual assessment of these preferences remains the best clinical approach.


Asunto(s)
Toma de Decisiones , Revelación , Educación del Paciente como Asunto/métodos , Participación del Paciente , Neoplasias de la Próstata/psicología , Neoplasias de la Próstata/terapia , Anciano , Humanos , Masculino , Estado Civil , Modelos Psicológicos , Medición de Riesgo , Rol del Enfermo , Encuestas y Cuestionarios , Resultado del Tratamiento
16.
JPEN J Parenter Enteral Nutr ; 19(4): 258-65, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8523623

RESUMEN

BACKGROUND: Active nutrition therapy and the anabolic steroid oxandrolone (OX), in selected patients with severe alcoholic hepatitis, significantly improved liver status and survival. We report here on the changes in their nutritional parameters. METHODS: Protein energy malnutrition (PEM) was evaluated and expressed as percent of low normal in 271 patients initially, at 1 month and at 3 months. Active therapy consisted of OX plus a high caloric food supplement vs a matching placebo and a low calorie supplement. RESULTS: PEM was present in every patient; mean PEM score 60% of low normal. Most of the parameters improved significantly from baseline on standard care; the largest improvement seen in visceral proteins, the smallest in fat stores (skinfold thickness). Total PEM score significantly correlated with 6 month mortality (p = .0012). Using logistic regression analysis, creatinine height index, hand grip strength and total peripheral blood lymphocytes were the best risk factors for survival. When CD lymphocyte subsets replaced total lymphocyte counts in the equation, CD8 levels became a significant risk factor (p = .004). Active treatment produced significant risk factor (p = .004). Active treatment produced significant improvements in those parameters related to total body and muscle mass (ie, mid arm muscle area, p = .02; creatinine height index, p = .03; percent ideal body weight, p = .04). CONCLUSION: Deterioration in nutritional parameters is a significant risk factor for survival in severe patients with alcoholic hepatitis. This deterioration is reversible with standard hospital care. Active therapy further improves creatinine height index, mid arm muscle area and total lymphocyte counts. Hence, these later parameters appear to be the best indicators for follow-up assessments.


Asunto(s)
Anabolizantes/uso terapéutico , Ingestión de Energía , Hepatitis Alcohólica/complicaciones , Oxandrolona/uso terapéutico , Desnutrición Proteico-Calórica/diagnóstico , Desnutrición Proteico-Calórica/terapia , Adulto , Anabolizantes/normas , Recuento de Células Sanguíneas , Antígenos CD4/análisis , Antígenos CD8/análisis , Terapia Combinada , Método Doble Ciego , Fuerza de la Mano/fisiología , Hepatitis Alcohólica/fisiopatología , Humanos , Subgrupos Linfocitarios/inmunología , Subgrupos Linfocitarios/patología , Masculino , Persona de Mediana Edad , Músculo Esquelético/fisiología , Oxandrolona/normas , Desnutrición Proteico-Calórica/etiología , Análisis de Regresión , Grosor de los Pliegues Cutáneos
17.
J Am Coll Nutr ; 14(2): 152-8, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7790689

RESUMEN

OBJECTIVE: Patients with alcoholic hepatitis frequently have moderate or severe malnutrition. Dietary protein intake may be restricted in these patients because of concurrent hepatic encephalopathy. To further evaluate the relationship between dietary protein intake and hepatic encephalopathy in alcoholic hepatitis, we evaluated prospectively gathered data from a study of 136 placebo-treated patients with moderate or severe alcoholic hepatitis conducted at eight Department of Veterans Affairs Medical Centers. METHODS: Physical examination, laboratory tests, and grade of hepatic encephalopathy were recorded at entry and every seventh day for the first 28 days of study. Average daily protein intake was calculated from dietary evaluation obtained by a registered dietitian at entry and again three times a week. RESULTS: Sixty-three percent of patients had hepatic encephalopathy at entry. Hepatic encephalopathy decreased over time. Time dependent regression analysis found low protein intake, along with high blood urea nitrogen (BUN) and high serum creatinine, to be independently associated with worsening hepatic encephalopathy. Similar analysis found low BUN and less malnutrition at entry into the study to be independently associated with improved hepatic encephalopathy. Higher protein intake was associated with improved hepatic encephalopathy in univariate (p = 0.01), but not multivariate, analysis. CONCLUSION: In patients with alcoholic hepatitis who can be treated with standard anti-encephalopathy medications (e.g., lactulose and neomycin), low protein intake is associated with worsening hepatic encephalopathy while a higher protein intake correlates with improvement in hepatic encephalopathy.


Asunto(s)
Proteínas en la Dieta/administración & dosificación , Encefalopatía Hepática/etiología , Hepatitis Alcohólica/complicaciones , Nitrógeno de la Urea Sanguínea , Creatinina/sangre , Proteínas en la Dieta/efectos adversos , Método Doble Ciego , Humanos , Cinética , Placebos , Estudios Prospectivos , Análisis de Regresión
18.
J Clin Gastroenterol ; 20(1): 42-4, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7884177

RESUMEN

We report results of dose escalation to 5 or 6 million units (MU) three times weekly (t.i.w.) of interferon-alpha in 17 consecutive patients with chronic active hepatitis C who were not responding to 3 MU t.i.w. after > or = 12 weeks of therapy. The mean pretreatment alanine aminotransferase (ALT) level was 206 +/- 62 U/L and, at the time of dose escalation, 113 +/- 71 U/L. Two patients could not tolerate the dose escalation. The remaining 15 patients were treated for an additional 10 +/- 3.5 weeks. Three patients had a complete response 3-8 weeks after dose escalation. At the end of high-dose therapy, the mean ALT level was 105 +/- 76 U/L (n = 15). During the 6-month posttreatment follow-up time, the mean ALT level was 147 +/- 85 U/L. All three responders had a relapse. Increasing the dose of interferon-alpha to 5-6 MU t.i.w. in chronic hepatitis C patients who are not responding to interferon-alpha, 3 MU t.i.w., at the 12th week of therapy is unlikely to result in sustained normalization of ALT levels.


Asunto(s)
Hepacivirus/efectos de los fármacos , Hepatitis Crónica/terapia , Interferón-alfa/administración & dosificación , Adulto , Anciano , Alanina Transaminasa/sangre , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Interferón alfa-2 , Masculino , Persona de Mediana Edad , Proteínas Recombinantes
19.
Hepatology ; 20(6): 1465-71, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7982646

RESUMEN

Alcoholic liver injury has been reported to be directed preferentially against the proteins of the cell membrane, sparing the phospholipids. However, antiphospholipid antibodies against certain cell membrane phospholipids are known to be associated with a variety of diseases. We undertook this investigation to determine whether antiphospholipid antibodies were present in the serum of patients with alcoholic liver disease. We investigated seventy long-term alcoholic patients (> 80 gm ethanol/day for > 1 yr) and 8 normal nonalcoholic controls by means of enzyme-linked immunosorbent assay to determine whether serum antibodies were generated against the following membrane phospholipids: phosphatidylserine, phosphatidylinositol, phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol (cardiolipin) and phosphatidic acid. Group 1 comprised alcoholic patients with normal liver function (n = 13), group 2 comprised alcoholic patients with abnormal liver function (n = 16), group 3 comprised patients with alcoholic hepatitis or cirrhosis (n = 41) and group 4 comprised nonalcoholic controls (n = 8). The antibody prevalence was 15% in group 1, 31% in group 2, 81% in group 3 and 0% in group 4. In group 3, 20 of 41 patients had antibodies against several cell membrane phospholipids (i.e., phosphatidylethanolamine, phosphatidylserine, phosphatidylglycerol, phosphatidic acid, cardiolipin and phosphatidylinositol). The antiphosphatidylethanolamine isotype was IgA or IgM in 25 of 41 of these patients. Both IgA (p < 0.01) and IgM (p < 0.008) antiphosphatidylethanolamine correlated significantly with disease severity. Antiphospholipid antibodies in alcoholic patients seem to reflect disease progression and correlate significantly with disease severity.


Asunto(s)
Anticuerpos Antifosfolípidos/metabolismo , Hepatopatías Alcohólicas/inmunología , Adulto , Anciano , Autoantígenos/inmunología , Cardiolipinas/inmunología , Distribución de Chi-Cuadrado , Ensayo de Inmunoadsorción Enzimática , Humanos , Inmunoglobulina A/metabolismo , Inmunoglobulina M/metabolismo , Persona de Mediana Edad , Fosfatidiletanolaminas/inmunología , Fosfatidilgliceroles/inmunología , Fosfatidilinositoles/inmunología , Fosfatidilserinas/inmunología
20.
Aviat Space Environ Med ; 65(5 Suppl): A75-9, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8018085

RESUMEN

Current high-performance fighter aircraft subject pilots to acceleration forces that can adversely effect performance and induce unconsciousness during flight. The main strategies to help the fighter pilot sustain +Gz include a pressurized anti-G garment (G-suit), the anti-G straining maneuver, and centrifuge training to optimize this effective, but very fatiguing, maneuver. To improve anti-G support for aircrew, a positive-pressure breathing anti-G system (PBG) has been developed in the COMBAT EDGE program. In order to determine if any acute adverse health effects are occurring from the use of PBG, a survey of 241 (F-15 and F-16) pilots (49 using PBG and 192 using standard methods) was conducted. Questions were asked regarding acute health effects and the impact of PBG on mission accomplishment. With the exception of dry cough, no significant increases in adverse events were found, and acceptance in the F-16 was much greater than in the F-15.


Asunto(s)
Medicina Aeroespacial , Comportamiento del Consumidor , Trajes Gravitatorios/efectos adversos , Personal Militar/psicología , Respiración con Presión Positiva/efectos adversos , Adulto , Tos/etiología , Humanos , Encuestas y Cuestionarios , Estados Unidos
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