Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
1.
Curr Oncol ; 25(Suppl 1): S161-S170, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29910659

RESUMEN

Background: Life expectancy for women with metastatic breast cancer has improved since the early 2000s, in part because of the introduction of novel therapies, including chemotherapy, hormonal therapy, and targeted agents. However, those treatments can come at a cost for the patient (short- and long-term toxicities from treatment) and at a financial cost for the health care system. Given the increase in the number of costly anticancer agents being introduced into the clinical setting, the American Society of Clinical Oncology (asco) and the European Society for Medical Oncology (esmo) have developed a system to quantify the value of new cancer treatments in terms of benefit, toxicities, and costs. Methods: In our value-assessment analysis, we included drugs that were funded in Canada between 2012 and 2017 for metastatic breast cancer. We reviewed the clinical benefit of those agents (survival, progression, quality of life), their costs, their value according to the asco and esmo value frameworks, and their assessments from the pan-Canadian Oncology Drug Review [pcodr (in Canada, except Quebec)] and the Institut national d'excellence en santé et en services sociaux [iness (in Quebec)]. Results: Drugs funded in Canada showed variation in their asco net health benefit scores and esmo magnitude of clinical benefit scores, but all had a cost-effectiveness ratio greater than $100,000 per quality-adjusted life-year. The strength and magnitude of the clinical benefit (for example, overall survival benefit vs. progression-free survival benefit) was not necessarily associated with a higher value score. Conclusions: Although great progress has been made in developing value frameworks, use of those frameworks has to be refined to help patients and health care providers make informed decisions about the benefit of novel cancer therapies and to help policymakers make decisions about the societal benefit of funding those therapies.


Asunto(s)
Antineoplásicos/economía , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/economía , Costos de los Medicamentos , Oncología Médica , Antineoplásicos/uso terapéutico , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/patología , Canadá/epidemiología , Análisis Costo-Beneficio , Toma de Decisiones , Costos de los Medicamentos/estadística & datos numéricos , Femenino , Humanos , Oncología Médica/economía , Oncología Médica/estadística & datos numéricos , Metástasis de la Neoplasia , Calidad de Vida , Años de Vida Ajustados por Calidad de Vida , Quebec/epidemiología , Sociedades Médicas , Análisis de Supervivencia
2.
Am J Epidemiol ; 154(11): 1064-71, 2001 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-11724724

RESUMEN

Vaccination at 6 months of age followed by routine revaccination is recommended when exposure of infants to measles is likely. Dade County, Florida, began this early two-dose schedule during a large epidemic in 1986-1987 (i.e., 22% of cases occurred in infants aged 6-11 months). This schedule was continued routinely in high-risk areas. The effect of an early two-dose schedule on measles prevention in the county was examined by comparing measles vaccination coverage and epidemiology before (1985-1987) and after (1988-1996) the schedule became routine. To assess serologic response, seroprevalence of measles antibody among children aged 4-6 years in 1995 was examined. To evaluate vaccine effectiveness, a case-control study was conducted among preschool-aged children. Among those aged 2 years, vaccination coverage with > or =1 dose increased from 75% to 94% in 1996. The number of annual cases declined, and endemic measles transmission reportedly ended after 1993. Seroprevalence of plaque reduction neutralization antibody (titer > 1:120) among those receiving vaccination according to an early two-dose schedule and a single dose at age > or =12 months was 94% (95% confidence interval: 89, 98) and 98% (95% confidence interval: 95, 100). In these groups, vaccine effectiveness was comparably high. Early two-dose measles vaccination is associated with improved coverage and a comparably high level of humoral immunity and clinical protection as a single dose at age > or =12 months. This strategy can be useful in areas at high risk for measles among infants.


Asunto(s)
Esquemas de Inmunización , Vacuna Antisarampión/administración & dosificación , Sarampión/inmunología , Sarampión/prevención & control , Anticuerpos Antivirales/sangre , Relación Dosis-Respuesta a Droga , Femenino , Florida , Humanos , Lactante , Modelos Logísticos , Masculino
3.
J Infect Dis ; 184(7): 817-26, 2001 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-11528592

RESUMEN

Immunizing infants against measles at the youngest age possible has the potential to reduce morbidity and mortality. The ability of infants at 6, 9, or 12 months to respond to measles and mumps vaccines was evaluated by measuring T cell proliferation, interferon-gamma production, and neutralizing antibody titers before and after vaccination. Infants in all age groups had equivalent cellular immune responses to measles or mumps viruses, with or without passive antibodies when immunized. In contrast, 6-month-old infants without passive antibodies had low geometric mean titers of antibody to measles or mumps viruses and low seroconversion rates. Geometric mean titers of antibody to measles virus increased if infants were revaccinated at 12 months. Six-month-old infants had limited humoral responses to paramyxovirus vaccines, whereas cellular immunity was equivalent to that of older infants. T cell responses can be established by immunization with these live attenuated virus vaccines during the first year, despite the presence of passive antibodies.


Asunto(s)
Vacuna Antisarampión/administración & dosificación , Sarampión/prevención & control , Morbillivirus/inmunología , Vacuna contra la Parotiditis/administración & dosificación , Paperas/prevención & control , Rubulavirus/inmunología , Vacunación , Adulto , Factores de Edad , Anticuerpos Antivirales/sangre , Estudios de Cohortes , Humanos , Lactante , Interferón gamma/sangre , Vacuna contra el Sarampión-Parotiditis-Rubéola/administración & dosificación , Linfocitos T/inmunología
4.
Arch Virol ; 146(12): 2369-83, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11811686

RESUMEN

In order to study structural associations, RSV surface glycoproteins were evaluated using heparin agarose affinity chromatography (HAAC). When RSV-infected cell lysate was analyzed by HAAC, all three surface glycoproteins, (F, G and SH), were eluted. Similarly, when separate lysates from Vero cells infected with vaccinia recombinants expressing F (vvF), G (vvG) and SH (vvSH) proteins were subjected to HAAC, only vvF and vvG expressed proteins bound to heparin, whereas vvSH expressed protein did not bind. When lysates from vvF, vvG and vvSH-infected Vero cells were mixed prior to HAAC, only F and G bound heparin. In contrast, following co-infection of Vero cells with vvF, vvG and vvSH, all three proteins were detected subsequent to HAAC. Following HAAC of A2-infected cell lysate and lysate from vvF, vvG and vvSH co-infected Vero cells, two high molecular weight complexes of 175 Kd and 210 Kd, respectively, were identified that reacted with anti-F, anti-G and anti-SH antisera. In addition, anti-SH antiserum was able to co-precipitate RSV F, G and SH. Using HAAC and a NaCl step gradient we demonstrated that a fraction of RSV F, G and SH eluted at higher salt concentrations than either purified F or G protein. Taken together, these data suggest that RSV F, G and SH glycoproteins can form an oligomeric complex within infected cells and this complex has a higher affinity for heparin than either G or F protein alone.


Asunto(s)
Virus Sincitial Respiratorio Humano/metabolismo , Proteínas Virales/metabolismo , Animales , Western Blotting , Chlorocebus aethiops , Cromatografía de Afinidad/métodos , Dimerización , Proteína HN/química , Proteína HN/metabolismo , Heparina/metabolismo , Humanos , Pruebas de Precipitina , Virus Sincitial Respiratorio Humano/patogenicidad , Células Vero , Proteínas del Envoltorio Viral , Proteínas Virales/química
5.
J Virol ; 74(14): 6442-7, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10864656

RESUMEN

Human respiratory syncytial virus (RSV) F glycoprotein (RSV-F) can independently interact with immobilized heparin and facilitate both attachment to and infection of cells via an interaction with cellular heparan sulfate. RSV-glycosaminoglycan (GAG) interactions were evaluated using heparin-agarose affinity chromatography. RSV-F from A2- and B1/cp-52 (cp-52)-infected cell lysates, RSV-F derived from a recombinant vaccinia virus, and affinity-purified F protein all bound to and were specifically eluted from heparin columns. In infectivity inhibition studies, soluble GAGs decreased the infectivity of RSV A2 and cp-52, with bovine lung heparin exhibiting the highest specific activity against both A2 (50% effective dose [ED(50)] = 0.28 +/- 0.11 microg/ml) and cp-52 (ED(50) = 0.55 +/- 0. 14 microg/ml). Furthermore, enzymatic digestion of cell surface GAGs by heparin lyase I and heparin lyase III but not chondroitinase ABC resulted in a significant reduction in cp-52 infectivity. Moreover, bovine lung heparin inhibited radiolabeled A2 and cp-52 virus binding up to 90%. Taken together, these data suggest that RSV-F independently interacts with heparin/heparan sulfate and this type of interaction facilitates virus attachment and infectivity.


Asunto(s)
Proteína HN , Heparitina Sulfato/metabolismo , Virus Sincitial Respiratorio Humano/metabolismo , Proteínas Virales de Fusión/metabolismo , Proteínas Virales/metabolismo , Animales , Bovinos , Adhesión Celular , Chlorocebus aethiops , Condroitina ABC Liasa/metabolismo , Cromatografía de Afinidad , Ensayo de Inmunoadsorción Enzimática , Glicosaminoglicanos/farmacología , Heparina/metabolismo , Heparina/farmacología , Liasa de Heparina/metabolismo , Humanos , Virus Sincitial Respiratorio Humano/patogenicidad , Células Vero , Proteínas del Envoltorio Viral , Proteínas Virales de Fusión/fisiología , Ensayo de Placa Viral , Proteínas Virales/fisiología
6.
Biologicals ; 28(1): 41-6, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10799055

RESUMEN

Pestiviruses are potential contaminants of biological products produced in bovine or porcine cells or manufactured via processes using animal-derived raw materials such as bovine serum. In order to investigate possible contamination of products including those manufactured and/or licensed in the US, 38 lots of viral vaccines and five lots of interferon alpha (IFNalpha) were tested by reverse transcriptase polymerase chain reaction (RT-PCR) for the presence of bovine viral diarrhoea virus (BVDV). All vaccines and interferons were negative for contaminating BVDV RNA when tested by RT-PCR, with the exception of an experimental live viral vaccine that had been produced in BVDV contaminated rabbit kidney cells. Cell lines commonly used to produce biological products and vaccines were experimentally infected with the NADL strain of BVDV to determine if they were permissive for virus replication. MRC-5 and WI-38 cells were not infected. In contrast, Vero, CHO and CEF cells showed evidence of pestivirus infection. Taken together these data suggested that currently licensed viral vaccines were unlikely to be contaminated with pestiviruses. However, cell banks derived from non-human primate, hamster or rabbit kidney cell lines, or cultures of primary chick embryo fibroblasts, may be infected with BVDV if exposed to pestivirus contaminated raw materials during manufacture.


Asunto(s)
Virus de la Diarrea Viral Bovina/aislamiento & purificación , Contaminación de Medicamentos , Interferón-alfa , Vacuna Antisarampión , Vacuna contra la Parotiditis , Vacuna Antipolio Oral , Vacuna contra la Rubéola , Animales , Bovinos , Línea Celular , Embrión de Pollo , Chlorocebus aethiops , Seguridad de Productos para el Consumidor , Cricetinae , Virus de la Diarrea Viral Bovina/genética , Estudios de Evaluación como Asunto , Humanos , Vacuna contra el Sarampión-Parotiditis-Rubéola , Conejos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Vacunas Combinadas , Células Vero
7.
J Immunol ; 163(2): 854-60, 1999 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-10395679

RESUMEN

Three human IFN-alpha hybrids, HY-1 [IFN-alpha21a(1-75)/alpha2c(76-165)], HY-2 [IFN-alpha21a(1-95)/alpha2c(96-165)], and HY-3 [IFN-alpha2c(1-95)/alpha21a(96-166)], were constructed, cloned, and expressed. The hybrids had comparable specific antiviral activities on Madin-Darby bovine kidney (MDBK) cells but exhibited very different antiproliferative and binding properties on human Daudi and WISH cells and primary human lymphocytes. Our data suggest that a portion of the N-terminal region of the molecule is important for interaction with components involved in binding of IFN-alpha2b while the C-terminal portion of IFN is critical for antiproliferative activity. A domain affecting the antiproliferative activity was found within the C-terminal region from amino acid residues 75-166. The signal transduction properties of HY-2 and HY-3 were evaluated by EMSA and RNase protection assays. Both HY-2 and HY-3 induced activation of STAT1 and 2. However, HY-2 exhibited essentially no antiproliferative effects at concentrations that activated STAT1 and 2. Additionally, at concentrations where no antiproliferative activity was seen, HY-2 induced a variety of IFN-responsive genes to the same degree as HY-3. RNase protection assays also indicate that, at concentrations where no antiproliferative activity was seen for HY-2, this construct retained the ability to induce a variety of IFN-inducible genes. These data suggest that the antiproliferative response may not be solely directed by the activation of the STAT1 and STAT2 pathway in the cells tested.


Asunto(s)
Interferón Tipo I/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Transducción de Señal/inmunología , Secuencia de Aminoácidos , Animales , Antivirales/farmacología , Bovinos , Células Cultivadas , Proteínas de Unión al ADN/metabolismo , Inhibidores de Crecimiento/farmacología , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/efectos de los fármacos , Humanos , Interferón Tipo I/química , Interferón Tipo I/aislamiento & purificación , Interferón Tipo I/farmacología , Interferón-alfa , Datos de Secuencia Molecular , Unión Proteica/efectos de los fármacos , Unión Proteica/inmunología , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/aislamiento & purificación , Proteínas Recombinantes de Fusión/fisiología , Proteínas Recombinantes , Factor de Transcripción STAT1 , Factor de Transcripción STAT2 , Transducción de Señal/efectos de los fármacos , Transactivadores/metabolismo , Transcripción Genética/efectos de los fármacos , Transcripción Genética/inmunología , Células Tumorales Cultivadas
8.
J Immunol ; 162(9): 5569-75, 1999 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-10228039

RESUMEN

Measles infection in infants is associated with severe complications, and secondary infections are attributed to generalized immunosuppression. Measles binding to its monocyte receptor down-regulates IL-12 which is expected to diminish Th1-like cytokine responses, including IFN-gamma. Whether young infants can be immunized effectively against measles is an important public health issue. We evaluated Ag-specific IL-12, IFN-gamma, and T cell responses of infants at 6 (n = 60), 9 (n = 46), or 12 mo (n = 56) of age and 29 vaccinated adults. IL-12 and IFN-gamma release by PBMC stimulated with measles Ag increased significantly after measles immunization in infants. IL-12 and IFN-gamma concentrations were equivalent in younger and older infants, but IL-12 concentrations were significantly lower in infants than in adults (p = 0.04). IL-12 production by monocytes was down-regulated by measles; the addition of recombinant human IL-12 enhanced IFN-gamma production by PBMC stimulated with measles Ag, but infant T cells released significantly less IFN-gamma than adult T cells under this condition. Of particular interest, the presence of passive Abs to measles had no effect on the specific T cell proliferation or IFN-gamma production after measles stimulation. Cellular immunity to measles infection and vaccination may be limited in infants compared with adults as a result of less effective IFN-gamma and IL-12 production in response to measles Ags. These effects were not exaggerated in younger infants compared with effects in infants who were immunized at 12 mo. In summary, infant T cells were primed with measles Ag despite the presence of passive Abs, but their adaptive immune responses were limited compared with those of adults.


Asunto(s)
Interferón gamma/biosíntesis , Interleucina-12/biosíntesis , Activación de Linfocitos/inmunología , Vacuna Antisarampión/inmunología , Linfocitos T/inmunología , Adulto , Factores de Edad , Anticuerpos Antivirales/biosíntesis , Anticuerpos Antivirales/fisiología , Epítopos de Linfocito T/inmunología , Humanos , Inmunidad Materno-Adquirida , Lactante , Interleucina-12/antagonistas & inhibidores , Interleucina-12/genética , Interleucina-12/farmacología , Activación de Linfocitos/efectos de los fármacos , Vacuna Antisarampión/farmacología , Monocitos/inmunología , Monocitos/metabolismo , Monocitos/virología , Pruebas de Neutralización , Fitohemaglutininas/inmunología , Proteínas Recombinantes/farmacología , Vacunas Atenuadas/inmunología , Vacunas Atenuadas/farmacología
9.
Blood ; 91(8): 3017-27, 1998 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-9531615

RESUMEN

Multiple biologic effects of interferon-alpha (IFN-alpha), including cell growth inhibition and antiviral protection, are initiated by tyrosine phosphorylation of STAT proteins. Although this signal pathway has been intensively investigated, the relevance of STAT signal persistence has received scant attention. Using paired isogenic lymphoma cells (Daudi), which either are sensitive or resistant to growth inhibition by IFN-alpha, we found comparable initial tyrosine phosphorylation of multiple STAT proteins; however, the phosphorylation durations and associated DNA-binding activities diverged. Phosphorylation and DNA-binding capacity of STAT1 decreased after 4 to 8 hours in resistant cells, as compared with 24 to 32 hours in sensitive cells, whereas phosphorylation of STAT3 and STAT5b was briefer in both lines. Functional significance of the prolonged STAT1 signal, therefore, was explored by experimental interruption of tyrosine phosphorylation, either by premature withdrawal of the IFN-alpha or deferred addition of pharmacologically diverse antagonists: staurosporine (protein kinase inhibitor), phorbol 12-myristate 13-acetate (growth promoter), or aurintricarboxylic acid (ligand competitor). Results indicated that an approximately 18-hour period of continued STAT1 phosphorylation was associated with growth arrest, but that antiviral protection developed earlier. These differences provide novel evidence of a temporal dimension to IFN-alpha signal specificity and show that duration of STAT1 activation may be a critical variable in malignant cell responsiveness to antiproliferative therapy.


Asunto(s)
Antineoplásicos/farmacología , Antivirales/farmacología , Proteínas de Unión al ADN/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Interferón gamma/farmacología , Linfoma/genética , Linfoma/patología , Proteínas de la Leche , Transducción de Señal/genética , Transactivadores/genética , División Celular/efectos de los fármacos , División Celular/genética , Humanos , Proteínas Recombinantes , Factor de Transcripción STAT1 , Factor de Transcripción STAT5 , Transducción de Señal/efectos de los fármacos , Células Tumorales Cultivadas
10.
Nature ; 390(6660): 629-32, 1997 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-9403695

RESUMEN

Signal transduction through both cytokine and lymphocyte antigen receptors shares some common pathways by which they initiate cellular responses, such as activation of mitogen-activated protein kinase(s). However, other signalling components appear to be uniquely coupled to each receptor. For example, the interferon receptors transduce regulatory signals through the JAK/STAT pathway, resulting in an inhibition of growth and of antiviral effects, whereas this pathway apparently plays no role in T-cell-receptor (TCR)-dependent gene expression. Conversely, signal transduction through the TCR requires the tyrosine kinases Lck and ZAP-70 and the tyrosine phosphatase CD45. Here we show that, unexpectedly, transmission of growth-inhibitory signals by interferon-alpha (IFN-alpha) in T cells requires the expression and association of CD45, Lck and ZAP-70 with the IFN-alpha-receptor signalling complex.


Asunto(s)
Inhibidores de Crecimiento/fisiología , Interferón-alfa/fisiología , Receptores de Antígenos de Linfocitos T/metabolismo , Transducción de Señal , Animales , Chlorocebus aethiops , Proteínas de Unión al ADN/metabolismo , Inhibidores de Crecimiento/metabolismo , Humanos , Técnicas In Vitro , Interferón-alfa/metabolismo , Células Jurkat , Antígenos Comunes de Leucocito/metabolismo , Proteína Tirosina Quinasa p56(lck) Específica de Linfocito/metabolismo , Virus del Sarampión/efectos de los fármacos , Virus del Sarampión/fisiología , Proteínas Tirosina Quinasas/metabolismo , Receptor de Interferón alfa y beta , Receptores de Interferón/metabolismo , Factor de Transcripción STAT1 , Factor de Transcripción STAT2 , Transactivadores/metabolismo , Células Vero , Replicación Viral/efectos de los fármacos , Proteína Tirosina Quinasa ZAP-70
11.
Lancet ; 345(8961): 1330-2, 1995 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-7752754

RESUMEN

Administration of 100,000 IU vitamin A at the time of measles immunisation is currently recommended for infants in developing countries. However, the safety and value of giving vitamin A, a potent immune enhancer, with live measles virus vaccines are unknown. We conducted a randomised, double-blind, placebo-controlled clinical trial in Indonesia to evaluate the effect of simultaneous vitamin A supplementation on the immune response to measles immunisation at six months of age. 336 infants received either vitamin A (100,000 IU) or placebo when immunised with standard-titre Schwarz measles vaccine. 82% of infants seroconverted to measles. In a multiple logistic regression model adjusting for maternal antibody titres, vitamin A supplementation was associated with a lower likelihood of seroconversion to measles (odds ratio 0.40, 95% CI 0.19-0.88), and girls were less likely to seroconvert than boys (0.34, 0.15-0.76). Immunisation with standard-titre Schwarz vaccine at six months of age in this study population is characterised by high seroconversion rates. However, simultaneous high-dose vitamin A may interfere with seroconversion to live measles vaccine in infants with maternal antibody.


PIP: In 19 villages in the Bogor District of West Java, Indonesia, between December 1992 and March 1993, pediatricians immunized 336 infants 6 months old with 0.5 ml of the standard-titer Schwarz measles vaccine and administered either 100,000 IU vitamin A (169 infants) or a placebo (167 infants) at the same time. The researchers wanted to determine the effect of vitamin A administration on antibody responses to the measles vaccination. 82% of 306 infants seroconverted to measles. About 33% of the 336 infants had no detectable maternal antibodies to measles, indicating that they were very vulnerable to measles infection. The multiple logistic regression model controlling for maternal antibody titers found that vitamin A administration reduced the likelihood of seroconversion to measles (odds ratio [OR] = 0.4). Females were less likely to seroconvert than males (OR = 0.34). At 1 and 6 months after immunization, infants who were administered vitamin A had a 25% lower geometric mean than those who were administered the placebo (p = 0.05 and 0.09, respectively). They were also less likely than the placebo group to develop a generalized rash (8.7% vs. 15.9%; p 0.05), suggesting that vitamin A may limit replication of vaccine-strain measles vaccine. These results suggest that simultaneous high- dose vitamin A may thwart seroconversion to live measles vaccine in infants with maternal antibodies. More research is needed.


Asunto(s)
Anticuerpos Antivirales/inmunología , Vacuna Antisarampión , Sarampión/inmunología , Vacunación , Vitamina A/uso terapéutico , Anticuerpos Antivirales/análisis , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Inmunidad Materno-Adquirida/inmunología , Indonesia , Lactante , Modelos Logísticos , Masculino , Sarampión/prevención & control , Virus del Sarampión/inmunología , Placebos , Factores Sexuales , Vitamina A/administración & dosificación
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA