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1.
J Viral Hepat ; 22(7): 596-606, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25412795

RESUMO

Alisporivir (ALV) is an oral, investigational host-targeting agent, with pangenotypic activity against hepatitis C virus (HCV). This randomized, double-blind, placebo-controlled, Phase II study explored the efficacy and safety of ALV with peginterferon-α2a/ribavirin (PR) in patients with chronic HCV genotype 1 infection in whom prior PR had failed (43% relapsers, 34% null responders and 23% partial responders). Four-hundred-and-fifty-nine patients were randomized (1:1:1:1) to ALV 600 mg once daily (QD), ALV 800 mg QD, ALV 400 twice daily (BID) or placebo plus PR for 48 weeks. When the global ALV trial programme was put on clinical hold, all patients in this study had received ≥31 weeks of randomized treatment; patients completed 48 weeks on PR alone. All ALV groups demonstrated superior rates of complete early virologic response (cEVR; primary endpoint) vs PR alone (P ≤ 0.0131), with highest cEVR rate seen with ALV 400 mg BID (74% vs 36% with PR alone; P < 0.0001). Respective SVR12 rates (key secondary endpoint) were 65% vs 26% in prior relapsers, 63% vs 5% in partial responders and 68% vs 3% in null responders. In patients who received >40 weeks of randomized treatment, the SVR12 rate was 89% for ALV 400 mg BID vs 30% for PR alone (P = 0.0053). Rates of viral breakthrough and relapse were lowest with ALV 400 mg BID. One case of pancreatitis (fully recovered) occurred with ALV/PR. Common AEs were headache, fatigue, anaemia, neutropenia and nausea. Hypertension was infrequent, but more common with ALV. ALV merits further investigation in interferon-free regimens in combination with direct-acting antiviral agents.


Assuntos
Antivirais/uso terapêutico , Ciclosporina/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Idoso , Antivirais/efeitos adversos , Ciclosporina/efeitos adversos , Método Duplo-Cego , Quimioterapia Combinada/efeitos adversos , Quimioterapia Combinada/métodos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Humanos , Interferon-alfa/efeitos adversos , Masculino , Pessoa de Meia-Idade , Placebos , Ribavirina/efeitos adversos , Terapia de Salvação/efeitos adversos , Terapia de Salvação/métodos , Resultado do Tratamento , Carga Viral , Adulto Jovem
2.
J Hosp Infect ; 131: 213-220, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36462673

RESUMO

BACKGROUND: Awareness and compliance with international guidelines for diagnosis and clinical management of Clostridioides difficile infection (CDI) are unknown. AIM: To compare the awareness and compliance with the recommended strategies for diagnosis and clinical management of CDI across Europe in 2018-2019. METHODS: Hospital sites and their associated community practices across 12 European countries completed an online survey in 2018-2019, to report on their practices in terms of surveillance, prevention, diagnosis, and treatment of CDI. Responses were collected from 105 hospitals and 39 community general practitioners (GPs). FINDINGS: Hospital sites of 11 countries reported participation in national surveillance schemes compared with six countries for international schemes. The European Society of Clinical Microbiology and Infectious Diseases (ESCMID)-recommended CDI testing methodologies were used by 82% (86/105) of hospitals, however countries reporting the highest incidence of CDI used non-recommended tests. Over 75% (80/105) of hospitals were aware of the most recent European CDI treatment guidelines at the time of this survey compared with only 26% (10/39) of surveyed GPs. However, up to 15% (16/105) of hospitals reported using the non-recommended metronidazole for recurrent CDI cases, sites in countries with lower awareness of CDI treatment guidelines. Only 37% (39/105) of hospitals adopted contact isolation precautions in case of suspected CDI. CONCLUSION: Good awareness of guidelines for the management of CDI was observed across the surveyed European hospital sites. However, low compliance with diagnostic testing guidelines, infection control measures for suspected CDI, and insufficient awareness of treatment guidelines continued to be reported in some countries.


Assuntos
Clostridioides difficile , Infecções por Clostridium , Humanos , Clostridioides , Europa (Continente)/epidemiologia , Infecções por Clostridium/diagnóstico , Infecções por Clostridium/tratamento farmacológico , Infecções por Clostridium/epidemiologia , Hospitais
3.
Am J Transplant ; 11(11): 2379-87, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21967703

RESUMO

Hepatitis C virus (HCV) causes progressive liver fibrosis in liver transplant recipients and is the principal cause of long-term allograft failure. The antifibrotic effects of sirolimus are seen in animal models but have not been described in liver transplant recipients. We reviewed 1274 liver recipients from 2002 to 2010 and identified a cohort of HCV recipients exposed to sirolimus as primary immunosuppression (SRL Cohort) and an HCV Control Group of recipients who had never received sirolimus. Yearly protocol biopsies were done recording fibrosis stage (METAVIR score) with biopsy compliance of >80% at both year one and two. In an intent-to-treat analysis, the SRL Cohort had significantly less advanced fibrosis (stage ≥2) compared to the HCV Control Group at year one (15.3% vs. 36.2%, p < 0.0001) and year two (30.1% vs. 50.5%, p = 0.001). Because sirolimus is sometimes discontinued for side effects, the SRL Cohort was subgroup stratified for sirolimus duration, showing progressively less fibrosis with longer sirolimus duration. Multivariate analysis demonstrated sirolimus as an independent predictor of minimal fibrosis at year one, and year two. This is the first study among liver transplant recipients with recurrent HCV to describe the positive impact of sirolimus in respect of reduced fibrosis extent and rate of progression.


Assuntos
Hepatite C/prevenção & controle , Transplante de Fígado/efeitos adversos , Sirolimo/uso terapêutico , Adulto , Infecções por Citomegalovirus/etiologia , Progressão da Doença , Feminino , Rejeição de Enxerto/etiologia , Hepacivirus/efeitos dos fármacos , Hepatite C/etiologia , Humanos , Terapia de Imunossupressão/métodos , Cirrose Hepática/epidemiologia , Cirrose Hepática/etiologia , Cirrose Hepática/virologia , Transplante de Fígado/patologia , Masculino , Pessoa de Meia-Idade , Sirolimo/administração & dosagem
4.
Am J Transplant ; 11(9): 1868-76, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21672151

RESUMO

In contrast to kidney transplantation where donor-specific anti-HLA antibodies (DSA) negatively impact graft survival, correlation of DSA with clinical outcomes in patients after orthotopic liver transplantation (OLT) has not been clearly established. We hypothesized that DSA are present in patients who develop chronic rejection after OLT. Prospectively collected serial serum samples on 39 primary OLT patients with biopsy-proven chronic rejection and 39 comparator patients were blinded and analyzed for DSA using LABScreen(®) single antigen beads test, where a 1000 mean fluorescence value was considered positive. In study patients, the median graft survival was 15 months, 74% received ≥ one retransplant, 20% remain alive and 87% had ≥ one episode of acute rejection. This is in contrast to comparator patients where 69% remain alive, and no patient needed retransplant or experienced rejection. Thirty-six chronic rejection patients (92%) and 24 (61%) comparator patients had DSA (p = 0.003). Chronic rejection versus comparator patients had higher mean fluorescence intensity (MFI) DSA. Although a further study with larger numbers of patients is needed to identify clinically significant thresholds, there is an association of high-MFI DSA with chronic rejection after OLT.


Assuntos
Autoanticorpos/imunologia , Rejeição de Enxerto/imunologia , Antígenos HLA/imunologia , Transplante de Fígado , Doadores de Tecidos , Adulto , Feminino , Fluorescência , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade
5.
J Cell Biol ; 105(3): 1191-203, 1987 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2821009

RESUMO

Two point mutations were introduced by oligonucleotide-directed mutagenesis into the region of the Rous sarcoma virus envelope gene that encodes the hydrophobic transmembrane anchor of the receptor glycoprotein. Single-nucleotide substitutions ultimately converted a hydrophobic leucine, located centrally within the membrane-spanning domain, to either a similarly hydrophobic methionine or a positively charged arginine. The altered coding region was reinserted into an intact copy of the envelope gene, cloned into simian virus 40 late-replacement vector and expressed in primate cells. Analysis of envelope gene expression in CV-1 monkey cells revealed normal levels of synthesis of a membrane-spanning precursor for both the mutants; however, the arginine-containing mutant [mu 26(arg)] exhibited greatly reduced cell surface expression of mature protein, as determined by indirect immunofluorescence and 125I labeling of surface proteins. In experiments in which cells producing the mu 26(arg) polypeptide were pulsed with radioactive leucine and then chased for 5 h, no intracellular accumulation or extracellular secretion of mature products (gp85 and gp37) could be detected. Treatment of mu 26(arg)-infected cells with lysosomal enzyme inhibitors (chloroquine and leupeptin) resulted in the accumulation of gp85 and gp37, indicating that they were being degraded rapidly in lysosomes. The fact that terminally glycosylated and proteolytically cleaved env gene products were observed under these conditions showed that modifications associated with passage through the trans compartment of the Golgi apparatus occurred normally on the mutant polypeptide; thus insertion of a highly charged amino acid into the transmembrane hydrophobic region of gp37 results in the postGolgi transport to lysosomes. It is proposed that the insertion of this mutation into the transmembrane anchor of the envelope glycoprotein does not affect membrane association, orientation with respect to the membrane, or intracellular transport at early stages during maturation. At a step late in the transport pathway, however, the presence of the charged side chain alters the protein in such a manner that the molecules are transported to the lysosomes and degraded. It seems likely that transport of the protein from the trans-Golgi to the cell surface is either directly blocked, or that after expression on the cell surface the mature glycoprotein complex is unstable and rapidly endocytosed.


Assuntos
Vírus do Sarcoma Aviário/genética , Genes Virais , Genes , Mutação , Processamento de Proteína Pós-Traducional , Transcrição Gênica , Proteínas do Envelope Viral/genética , Sequência de Aminoácidos , Animais , Linhagem Celular , Vetores Genéticos , Plasmídeos
6.
Aliment Pharmacol Ther ; 26(9): 1187-94, 2007 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-17944733

RESUMO

BACKGROUND: Serum alpha fetoprotein (AFP), ultrasound, computerized tomography scanning, and magnetic resonance imaging are commonly used to screen for hepatocellular carcinoma (HCC) in patients with cirrhosis. AIM: To assess the accuracy of screening in advanced cirrhosis. METHODS: The study group consisted of 239 patients with proven HCC in the explanted liver at the time of liver transplant. AFP and imaging were done at referral and serially until transplant. RESULTS: Hepatocellular carcinoma was detected before liver transplant in 78% and discovered incidentally in 22%. The cause of cirrhosis was hepatitis C (HCV) (55%), hepatitis B (HBV) (17%), alcohol (9%), and other/unknown (19%). Although AFP was elevated 62%, the median level was 15 ng/mL. Only 26%, 15% and 13% were more than 100, 400 and 1000 ng/mL, respectively. By comparison, AFP was elevated in 20% without HCC, but exceeded 100 ng/mL in only 3%. The overall accuracy of AFP was poor regardless of the cutoff. Magnetic resonance imaging was more accurate than computerized tomography or ultrasound in detecting tumour, particularly when performed within 3 months of transplant. CONCLUSIONS: Magnetic resonance imaging is most sensitive for imaging HCC and best reflects actual tumour size. AFP is insensitive and adds little to screening strategies, but has prognostic value when extremely elevated.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Cirrose Hepática/diagnóstico , Neoplasias Hepáticas/diagnóstico , alfa-Fetoproteínas/metabolismo , Adolescente , Adulto , Idoso , Carcinoma Hepatocelular/diagnóstico por imagem , Feminino , Humanos , Cirrose Hepática/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Transplante de Fígado , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X , Ultrassonografia
7.
Cancer Res ; 47(13): 3577-83, 1987 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-3555775

RESUMO

Murine variable and human constant region exons were fused to produce "chimeric" immunoglobulin gamma and kappa genes. These constructs were cotransfected into murine myeloma cells which then produced and secreted intact, functional antibody. Cells secreting the chimeric antibody were introduced into mice. The engineered immunoglobulin was subsequently harvested from ascites fluid and was purified by affinity chromatography. Its immunological properties were compared to those of the parental murine monoclonal (B6.2), which exhibits specificity for human breast, lung, and colon carcinoma cells. Competitive binding, immunofluorescent cell staining, and analysis of immunoprecipitated antigen gave similar results for the chimeric and murine B6.2. The biodistribution of chimeric and murine B6.2 after injection into mice bearing human tumors was found to be identical. These results suggest that murine/human chimeric antibodies may be viable clinical replacements for murine monoclonals with the potential for better immunological tolerance and pharmacological efficacy.


Assuntos
Anticorpos Monoclonais/genética , Anticorpos Antineoplásicos/genética , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Antineoplásicos/imunologia , Especificidade de Anticorpos , Antígenos de Neoplasias/imunologia , Ligação Competitiva , Quimera , Imunofluorescência , Engenharia Genética , Humanos , Hibridomas , Camundongos , Transplante de Neoplasias , Neoplasias Experimentais/diagnóstico por imagem , Cintilografia , Distribuição Tecidual
8.
Cancer Res ; 43(9): 4434-42, 1983 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6347372

RESUMO

Thirteen of 14 tumor cells or tumor cell lines of guinea pig, mouse, and human origin spontaneously shed procoagulant activity in short-term (4 or 14 to 22 hr) tissue culture under conditions of high cell viability. This released procoagulant activity was pelletable in the ultracentrifuge and was associated with plasma membrane-derived vesicles as determined by transmission electron microscopy and marker enzyme analysis. The procoagulant activity shed corresponded to a substantial fraction of that expressed by intact or sonicated tumor cells and was composed of activities interacting at more than a single step in the clotting sequence. One procoagulant activity associated with shed human tumor vesicles behaved as tissue factor, requiring Factor VII for activity and being inhibited by a specific anti-bovine tissue factor antibody. Guinea pig tumor vesicles also exhibited tissue factor-like activity in a two-stage assay using homologous first-stage Factor VII/X concentrate. None of the human vesicles tested expressed a direct Factor X cleaving activity, independent of Factor VII. Shed tumor vesicles also acted at a second step late in the clotting cascade at the level of prothrombinase generation, presumably by providing a phospholipid surface. Taken together, these data indicate that a wide variety of tumor cells release plasma membrane vesicles with procoagulant activity. Such vesicles, as well as intact tumor cells themselves, may play an important role in the biology of tumor growth by inducing the local fibrin deposits found in association with many solid tumors.


Assuntos
Fatores de Coagulação Sanguínea/metabolismo , Cisteína Endopeptidases , Endopeptidases/metabolismo , Proteínas de Neoplasias , Neoplasias/fisiopatologia , Precursores de Proteínas/metabolismo , Animais , Linhagem Celular , Membrana Celular/fisiologia , Cobaias , Humanos , Camundongos , Neoplasias Experimentais/fisiopatologia , Especificidade da Espécie
9.
J Am Coll Cardiol ; 27(2): 375-83, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8557909

RESUMO

OBJECTIVES: This study was designed to investigate disturbances in arterial blood pressure and body fluid homeostasis in stable heart transplant recipients. BACKGROUND: Hypertension and fluid retention frequently complicate heart transplantation. METHODS: Blood pressure, renal and endocrine responses to acute volume expansion were compared in 10 heart transplant recipients (57 +/- 9 years old [mean +/- SD]) 20 +/- 5 months after transplantation, 6 liver transplant recipients receiving similar doses of cyclosporine (cyclosporine control group) and 7 normal volunteers (normal control subjects). After 3 days of a constant diet containing 87 mEq/24 h of sodium, 0.154 mol/liter saline was infused at 8 ml/kg per h for 4 h. Blood pressure and plasma vasopressin, angiotensin II, aldosterone, atrial natiuretic peptide and renin activity levels were determined before and at 30, 60, 120 and 240 min during the infusion. Urine was collected at 2 and 4 h. Blood pressure, fluid balance hormones and renal function were monitored for 48 h after the infusion. RESULTS: Blood pressure did not change in the two control groups but increased in the heart transplant recipients (+15 +/- 8/8 +/- 5 mm Hg) and remained elevated for 48 h (p < or = 0.05). Urine flow and urinary sodium excretion increased abruptly in the control groups sufficient to account for elimination of 86 +/- 9% of the sodium load by 48 h; the increases were blunted (p < or = 0.05) and delayed in the heart transplant recipients, resulting in elimination of only 51 +/- 13% of the sodium load. Saline infusion suppressed vasopressin, renin activity, angiotensin II and aldosterone in the two control groups (p < or = 0.05) but not in the heart transplant recipients. Heart transplant recipients had elevated atrial natriuretic peptide levels at baseline (p < or = 0.05), but relative increases during the infusion were similar to those in both control groups. CONCLUSIONS: Blood pressure in heart transplant recipients is salt sensitive. These patients have a blunted diuretic and natriuretic response to volume expansion that may be mediated by a failure to reflexly suppress fluid regulatory hormones. These defects in blood pressure and fluid homeostasis were not seen in liver transplant recipients receiving cyclosporine and therefore cannot be attributed to cyclosporine alone. Abnormal cardiorenal neuroendocrine reflexes, secondary to cardiac denervation, may contribute to salt-sensitive hypertension and fluid retention in heart transplant recipients.


Assuntos
Transplante de Coração/efeitos adversos , Hipertensão/etiologia , Sódio na Dieta/farmacologia , Desequilíbrio Hidroeletrolítico/etiologia , Angiotensina II/sangue , Arginina Vasopressina/sangue , Fator Natriurético Atrial/sangue , Pressão Sanguínea/fisiologia , Estudos de Casos e Controles , Ciclosporina/uso terapêutico , Feminino , Coração/inervação , Transplante de Coração/fisiologia , Humanos , Hipertensão/fisiopatologia , Imunossupressores/uso terapêutico , Transplante de Fígado/fisiologia , Masculino , Pessoa de Meia-Idade , Sistema Renina-Angiotensina/fisiologia , Cloreto de Sódio , Função Ventricular Esquerda/fisiologia , Equilíbrio Hidroeletrolítico/fisiologia , Desequilíbrio Hidroeletrolítico/fisiopatologia
10.
Genetics ; 152(3): 1137-72, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10388831

RESUMO

We have constructed a 1736-locus maize genome map containing1156 loci probed by cDNAs, 545 probed by random genomic clones, 16 by simple sequence repeats (SSRs), 14 by isozymes, and 5 by anonymous clones. Sequence information is available for 56% of the loci with 66% of the sequenced loci assigned functions. A total of 596 new ESTs were mapped from a B73 library of 5-wk-old shoots. The map contains 237 loci probed by barley, oat, wheat, rice, or tripsacum clones, which serve as grass genome reference points in comparisons between maize and other grass maps. Ninety core markers selected for low copy number, high polymorphism, and even spacing along the chromosome delineate the 100 bins on the map. The average bin size is 17 cM. Use of bin assignments enables comparison among different maize mapping populations and experiments including those involving cytogenetic stocks, mutants, or quantitative trait loci. Integration of nonmaize markers in the map extends the resources available for gene discovery beyond the boundaries of maize mapping information into the expanse of map, sequence, and phenotype information from other grass species. This map provides a foundation for numerous basic and applied investigations including studies of gene organization, gene and genome evolution, targeted cloning, and dissection of complex traits.


Assuntos
Mapeamento Cromossômico , Etiquetas de Sequências Expressas , Marcadores Genéticos , Genoma de Planta , Zea mays/genética , Modelos Genéticos , Sitios de Sequências Rotuladas
11.
Clin Pharmacol Ther ; 37(4): 396-401, 1985 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3979001

RESUMO

Experimental and more limited clinical studies have suggested that influenza vaccination may depress the oxidative hepatic metabolism of various drugs and lead to drug toxicity. The alleged mechanism is the formation of interferon and the resulting decrease in cytochrome P-450 available for drug oxidation. Because of the clinical and basic science implications of these reports, we undertook to study the effects of influenza vaccine on the metabolism of three commonly used drugs: chlordiazepoxide, theophylline, and lorazepam. Our healthy male subjects were studied just before and 1 and 7 days after vaccination. As expected, lorazepam metabolism, which proceeds by glucuronidation and not oxidation, was not altered by vaccination. Surprisingly, however, the oxidation of chlordiazepoxide was also not depressed by the vaccine. Theophylline oxidation, which proceeds primarily by microsomal oxidation (demethylation), was significantly decreased 1 day, but not 7 days, after vaccination. Serum alpha-interferon levels rose after vaccination for only about 8 hours, and levels of gamma-interferon rose to about 500 IU/ml at 24 hours, peaked at 72 hours, and returned to normal by 100 hours after dosing. It appeared that the higher the theophylline clearance before vaccination, the greater the degree of clearance depression after vaccination. Thus the inhibition of drug oxidation after influenza vaccination is selective and each drug should be studied individually. The degree of depression of theophylline clearance is small and transient and appears to be greater in subjects with higher prevaccination clearance.


Assuntos
Clordiazepóxido/metabolismo , Vacinas contra Influenza/farmacologia , Fígado/efeitos dos fármacos , Lorazepam/metabolismo , Teofilina/metabolismo , Adulto , Clordiazepóxido/sangue , Cromatografia Líquida de Alta Pressão , Meia-Vida , Humanos , Interferon Tipo I/sangue , Cinética , Fígado/metabolismo , Lorazepam/sangue , Masculino , Análise de Regressão , Teofilina/sangue
12.
Gene ; 96(2): 305-9, 1990 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-2269442

RESUMO

Segments of a cDNA encoding human plasminogen activator inhibitor type 1 (PAI-1) were subcloned into a highly regulated and inducible Escherichia coli expression system. A plasmid encoding the mature form of human endothelial PAI-1 produced a functional recombinant molecule, as indicated by its ability to inhibit tissue plasminogen activator's enzymatic activity. In contrast to PAI-1 isolated from human fibrosarcoma cells, the biological activity of the recombinant PAI-1 was not dependent on pretreatment with denaturing agents. A construct encoding a polypeptide lacking the first 80 amino acids of PAI-1 also produced elevated levels of the truncated recombinant protein. However, this truncated product was functionally inactive, indicating that an intact N terminus is required for activity.


Assuntos
Escherichia coli/genética , Expressão Gênica , Inativadores de Plasminogênio/metabolismo , Sequência de Aminoácidos , Clonagem Molecular , DNA Recombinante/genética , Escherichia coli/metabolismo , Humanos , Dados de Sequência Molecular , Plasmídeos , Inativadores de Plasminogênio/farmacologia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/farmacologia
13.
Antivir Ther ; 4(1): 15-9, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10682124

RESUMO

Two patients with chronic hepatitis C virus (HCV) genotype 2b infection were studied. They responded biochemically to interferon (IFN) but had early virological and later biochemical relapse. The HCV quasispecies equilibrium in these patients was studied by a combination of cloning, sequencing and construction of phylogenetic trees. Another patient with chronic HCV genotype 2b infection was followed every 6 months for 30 months (including one episode of biochemical exacerbation) to serve as the control. Quasispecies equilibrium drifted during IFN therapy but moved back in the direction of the original equilibrium during biochemical relapse. In the control patient, there was no significant drifting throughout the follow-up period. These data suggest that IFN therapy exerts selective pressure on HCV quasispecies equilibrium.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/classificação , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Adulto , Alanina Transaminase/sangue , Feminino , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia
14.
Am J Med ; 96(1A): 41S-46S, 1994 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-7509123

RESUMO

The natural history of chronic hepatitis C is just beginning to be clarified, with its more common course being an insidiously progressive liver disease that often remains clinically inconsequential for many years or even decades. Although chronic hepatitis C progresses histologically, the impact on the clinical well-being of the patient is less evident. Interferon is an effective therapy for this disease because of its antiviral effect on the cytopathic hepatitis C virus, lowering serum alanine aminotransferase (ALT) levels, rather than because of any immune modulatory mechanism. Unfortunately, interferon therapy does not permanently eradicate hepatitis C virus in the majority of patients, and relapse with return of the serum ALT level to the pretreatment range occurs in approximately 70% of responding patients. Other interferon-treated patients continue to be viremic and are not considered to be responders. In addition, not all patients with chronic hepatitis C require treatment. A systematic approach to patient evaluation is necessary to determine the need for treatment, assess treatment response, identify side effects of therapy, and assist in other clinical decisions.


Assuntos
Hepatite C/terapia , Interferons/uso terapêutico , Doença Crônica , Humanos
15.
Am J Med ; 107(6B): 21S-26S, 1999 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-10653451

RESUMO

Genetic heterogeneity is a hallmark of the hepatitis C virus, as a result largely of the infidelity of viral RNA-dependent RNA polymerase. Random nucleotide substitutions are introduced at a very high rate. The existence of genotypes was confirmed by statistical and mathematical techniques, and the relation of the genotypes to each other has been determined. There are six major genotypes, each with multiple subtypes. Isolates of the same genotype have an average sequence homology of 95%, but different genotypes have sequence similarity of approximately 65% on average. The nucleotide sequence in portions of the hepatitis C viral genome, including the 5' noncoding region, part of the core gene, and other nonstructural proteins, is highly conserved. Genotype analysis typically utilizes these highly conserved regions. There are many techniques for determining viral genotype, and in general, concordance between techniques is good. Methods most commonly used for assigning hepatitis C virus (HCV) genotypes in clinical practice include restriction fragment length polymorphism analysis and the reverse hybridization line probe assay (LiPA; Innogenetics, Ghent, Belgium). The worldwide distribution of HCV genotypes has been determined; some genotypes are highly characteristic of certain areas. The most common subtypes, 1 and 2, are less genetically diverse than the others and are more widely distributed. The impact of genotype on disease course is controversial, but recent data suggest that there is a genotype-dependent differential response to therapy. Quasispecies refers to evolution of a highly related but genetically heterogeneous population of HCV isolates. The pathobiological and clinical implications of HCV quasispecies are poorly understood.


Assuntos
Hepacivirus/genética , Genoma Viral , Genótipo , Hepacivirus/classificação , Hepatite C/epidemiologia , Hepatite C/virologia , Humanos , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição
16.
Am J Med ; 63(6): 1015-22, 1977 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-605904

RESUMO

Two well documented examples of nonsecretory multiple myeloma were studied by electron microscopic and immunohistologic methods. In one case, repeat studies revealed no intracytoplasmic immunoglobulins, and the cells displayed a "plasmacytoid" appearance with poor development of rough endoplasmic reticulum and Golgi regions. In the other case, most cells contained intracytoplasmic immmunoglobulins of a monoclonal type and the ultrastructural appearance was that of cells actively engaged in protein synthesis. These findings and others in the literature suggest that myelomas without an M component can be separated into nonproducers and true nonsecretors of immunoglobulins. In one case, immunofluorescence of bone marrow smears with double labels demonstrated three different plasma cell populations: those producing either monoclonal immunoglobulins M (IgM) or A (IgA) and those synthesizing simultaneously IgM and IgM. Dual immunoglobulin production, although known to occur in myelomas with paraproteinemia, has not been previously documented in the nonsecretory variety.


Assuntos
Mieloma Múltiplo/metabolismo , Medula Óssea/patologia , Núcleo Celular/ultraestrutura , Retículo Endoplasmático/ultraestrutura , Complexo de Golgi/ultraestrutura , Humanos , Imunoglobulinas/biossíntese , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/imunologia , Mieloma Múltiplo/ultraestrutura , Plasmócitos/ultraestrutura
17.
Am J Med ; 80(3): 523-5, 1986 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3953630

RESUMO

Gaucher's disease, an inherited metabolic disorder, may cause hepatic fibrosis, but hepatic inflammation does not occur as part of the disorder. The case of an 18-year-old girl of Ashkenazic Jewish ancestry with chronic active hepatitis and coexistent Gaucher's disease is presented. The clinical course of remissions and exacerbations of the disease activity was typical of "autoimmune" chronic active hepatitis and seemed unaffected by the coexistence of Gaucher's disease. Steroid and immunosuppressive treatment resulted in prompt resolution of the chronic hepatitis. Gaucher's disease results in B cell stimulation and polyclonal gammopathy, which may have contributed to the hypergammaglobulinemia associated with idiopathic ("autoimmune") chronic hepatitis in this case.


Assuntos
Doença de Gaucher/complicações , Hepatite Crônica/complicações , Adolescente , Azatioprina/administração & dosagem , Quimioterapia Combinada , Feminino , Hepatite Crônica/tratamento farmacológico , Humanos , Prednisona/administração & dosagem
18.
Am J Med ; 108(5): 366-73, 2000 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10759092

RESUMO

PURPOSE: Many patients with chronic hepatitis C who are treated with interferon suffer a relapse after an initial response. About half of these patients have a sustained virological response to retreatment with the combination of ribavirin and interferon alfa-2b. The aim of this study was to estimate the cost effectiveness of retreatment with combination therapy versus interferon alone for patients who have previously relapsed after interferon. SUBJECTS AND METHODS: Data from a randomized trial among 345 relapsed patients that compared combination therapy with interferon alone were used to project lifelong clinical and economic outcomes. Natural history and economic estimates (discounted at 3% per year) were based upon published literature, expert panel estimates, and cost and reimbursement data. RESULTS: Compared with retreatment with interferon alone, combination therapy should prolong life expectancy by about 2 discounted quality-adjusted life years (3 life years, undiscounted) while increasing costs modestly. The results were robust, maintaining an advantage to combination therapy in sensitivity analysis for all subgroups and with reasonable variations in all model parameters. CONCLUSION: For patients with chronic hepatitis C who relapse after an initial response to interferon alone, retreatment with the combination of ribavirin and interferon alfa-2b should prolong life and be cost effective.


Assuntos
Antivirais/economia , Antivirais/uso terapêutico , Custos de Medicamentos/estatística & dados numéricos , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/economia , Interferon-alfa/economia , Interferon-alfa/uso terapêutico , Ribavirina/economia , Ribavirina/uso terapêutico , Adulto , Análise Custo-Benefício , Quimioterapia Combinada , Feminino , Hepatite C Crônica/complicações , Humanos , Interferon alfa-2 , Expectativa de Vida , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes , Recidiva , Análise de Sobrevida , Resultado do Tratamento , Estados Unidos
19.
Transplantation ; 56(6): 1364-7, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7506451

RESUMO

One hundred renal transplant recipients were studied for antibodies to hepatitis C virus (HCV), and to HCV RNA in serum by reverse transcription+nested polymerase chain reaction (RT-PCR). Presence of antibody to HCV confirmed by recombinant immunoblot assay II was considered evidence of HCV infection, and detection of HCV RNA by RT-PCR was considered evidence for active viremia. On pretransplant sera, 18 patients were RT-PCR positive and an additional 3 had antibody evidence of HCV infection. At 1-year follow-up, all of these patients were RT-PCR positive and an additional 7 patients became RT-PCR positive. Clinical diagnosis of non-A, non-B hepatitis underestimated the prevalence of HCV infection (5/28 cases, 18%). Serum alanine aminotransferase (ALT) elevations were neither sensitive nor specific. An isolated pretransplant ALT elevation predicted a 52% chance of being RT-PCR positive for HCV. An ALT elevation greater than 2 months after transplant predicted a 45% chance of HCV positivity; however, 18% of patients who never had any ALT abnormality were also HCV positive. Sixty-eight patients had an early postoperative rise in ALT, but there was no correlation with HCV status. After an average follow-up of over 4 years, 3/28 HCV-positive patients developed cirrhosis. HCV infection in the renal transplant population is common and underdiagnosed by clinical and biochemical parameters. HCV appears not to cause aggressive liver disease in the early posttransplant period, but longer follow-up is needed to define the natural history of HCV in the renal transplant population.


Assuntos
Alanina Transaminase/sangue , Hepatite C/transmissão , Transplante de Rim/efeitos adversos , Adulto , Idoso , Feminino , Hepacivirus/genética , Hepacivirus/imunologia , Hepacivirus/isolamento & purificação , Anticorpos Anti-Hepatite/sangue , Hepatite C/diagnóstico , Hepatite C/enzimologia , Anticorpos Anti-Hepatite C , Humanos , Transplante de Rim/fisiologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Reação Transfusional
20.
Transplantation ; 58(1): 114-6, 1994 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-8036699

RESUMO

A critically ill, HBV seronegative girl who received a liver from a HBsAg+ donor is described. Despite HBV Ig prophylaxis, she was seropositive for HBsAg shortly after transplantation. Although the postoperative period was complicated, HBV-related problems were not encountered. Liver dysfunction was noted 7 months after transplantation. At that time, she became anti-HBc IgM-positive, with liver histologic findings suggestive of chronic active hepatitis B. The liver function normalized after a reduction of immunosuppressive therapy and introduction of ciprofloxacin. The patient had low level HBV replication during the entire follow-up period (HBV DNA-positive by PCR only) and sequencing of the virus on 4 occasions revealed only wild-type HBV. She subsequently lost serum HBsAg and HBV DNA (even by PCR) and has remained well 2 years after transplantation.


Assuntos
Antígenos de Superfície da Hepatite B/análise , Hepatite B/transmissão , Transplante de Fígado/imunologia , Doadores de Tecidos , Sequência de Bases , Criança , Doença Crônica , DNA Viral/análise , Feminino , Vírus da Hepatite B/fisiologia , Humanos , Imunossupressores/uso terapêutico , Dados de Sequência Molecular
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