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1.
Eur Urol Focus ; 8(5): 1238-1245, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-34893458

RESUMEN

BACKGROUND: High-risk muscle-invasive bladder cancer (MIBC) has a poor prognosis. Old trials showed that external beam radiotherapy (EBRT) after radical cystectomy (RC) decreases the incidence of local recurrences but induces severe toxicity. OBJECTIVE: To evaluate the toxicity and local control rate after adjuvant EBRT after RC delivered with volumetric arc radiotherapy. DESIGN, SETTING, AND PARTICIPANTS: This is a multicentric phase 2 trial. From August 2014 till October 2020, we treated 72 high-risk MIBC patients with adjuvant EBRT after RC. High-risk MIBC is defined as ≥pT3-MIBC ± lymphovascular invasion, fewer than ten lymph nodes removed, pathological positive lymph nodes, or positive surgical margins. INTERVENTION: Patients received 50 Gy in 25 fractions with intensity-modulated radiotherapy to the pelvic lymph nodes ± cystectomy bed. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary outcome is acute toxicity. We report on local relapse-free rate (LRFR), clinical relapse-free survival (CRFS), overall survival (OS), and bladder cancer-specific survival (BCSS). RESULTS AND LIMITATIONS: The median follow-up is 18 mo. Forty-two patients (61%) developed acute grade 2 gastrointestinal (GI) toxicity. Four patients (6%) had acute grade 3 GI toxicity. One patient had grade 5 diarrhea and vomiting due to obstruction at 1 mo. Two-year probabilities of developing grade ≥3 and ≥2 GI toxicity were 17% and 76%, respectively. Urinary toxicity, assessed in 17 patients with a neobladder, was acceptable with acute grade 2 and 3 urinary toxicity reported in 53% (N = 9) and 18% (N = 3) of the patients, respectively. The 2-yr LRFR is 83% ± 5% and the 2-yr CRFS rate is 43% with a median CRFS time of 12 mo (95% confidence interval: 3-21 mo). Two-year OS and BCSS are 52% ± 7% and 62% ± 7%, respectively. Shortcomings are the nonrandomized study design and limited follow-up. CONCLUSIONS: Adjuvant EBRT after RC can be administered without excessive severe toxicity. PATIENT SUMMARY: In this report, we looked at the incidence of toxicity and local control after adjuvant external beam radiotherapy (EBRT) following radical cystectomy (RC) in high-risk muscle-invasive bladder cancer patients. We found that adjuvant EBRT was feasible and resulted in good local control. We conclude that these data support further enrollment of patients in ongoing trials to evaluate the place of adjuvant EBRT after RC.


Asunto(s)
Cistectomía , Neoplasias de la Vejiga Urinaria , Humanos , Cistectomía/métodos , Neoplasias de la Vejiga Urinaria/radioterapia , Neoplasias de la Vejiga Urinaria/cirugía , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Radioterapia Adyuvante , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/cirugía , Músculos/patología
2.
Sci Rep ; 9(1): 18120, 2019 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-31792342

RESUMEN

Natural-product derived lectins can function as potent viral inhibitors with minimal toxicity as shown in vitro and in small animal models. We here assessed the effect of rectal application of an anti-HIV lectin-based microbicide Q-Griffithsin (Q-GRFT) in rectal tissue samples from rhesus macaques. E-cadherin+ cells, CD4+ cells and total mucosal cells were assessed using in situ staining combined with a novel customized digital image analysis platform. Variations in cell numbers between baseline, placebo and Q-GRFT treated samples were analyzed using random intercept linear mixed effect models. The frequencies of rectal E-cadherin+ cells remained stable despite multiple tissue samplings and Q-GRFT gel (0.1%, 0.3% and 1%, respectively) treatment. Whereas single dose application of Q-GRFT did not affect the frequencies of rectal CD4+ cells, multi-dose Q-GRFT caused a small, but significant increase of the frequencies of intra-epithelial CD4+ cells (placebo: median 4%; 1% Q-GRFT: median 7%) and of the CD4+ lamina propria cells (placebo: median 30%; 0.1-1% Q-GRFT: median 36-39%). The resting time between sampling points were further associated with minor changes in the total and CD4+ rectal mucosal cell levels. The results add to general knowledge of in vivo evaluation of anti-HIV microbicide application concerning cellular effects in rectal mucosa.


Asunto(s)
Fármacos Anti-VIH/farmacología , Antiinfecciosos Locales/farmacología , Mucosa Intestinal/efectos de los fármacos , Lectinas/farmacología , Lectinas de Plantas/farmacología , Recto/efectos de los fármacos , Animales , Fármacos Anti-VIH/administración & dosificación , Antígenos CD4/metabolismo , Cadherinas/metabolismo , Recuento de Células , Células Epiteliales/efectos de los fármacos , Mucosa Intestinal/citología , Mucosa Intestinal/inmunología , Lectinas/administración & dosificación , Macaca mulatta , Lectinas de Plantas/administración & dosificación , Proteínas Recombinantes , Recto/citología , Recto/inmunología , Factores de Tiempo
3.
Circ Res ; 113(10): 1159-68, 2013 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-24036495

RESUMEN

RATIONALE: Mutations in fibrillin-1 are associated with thoracic aortic aneurysm (TAA) in Marfan syndrome. Genome-wide association studies also implicate fibrillin-1 in sporadic TAA. Fragmentation of the aortic elastic lamellae is characteristic of TAA. OBJECTIVE: Immunoassays were generated to test whether circulating fragments of fibrillin-1, or other microfibril fragments, are associated with TAA and dissection. METHODS AND RESULTS: Plasma samples were obtained from 1265 patients with aortic aneurysm or dissection and from 125 control subjects. Concentrations of fibrillin-1, fibrillin-2, and fibulin-4 were measured with novel immunoassays. One hundred and seventy-four patients (13%) had aneurysms with only abdominal aortic involvement (abdominal aortic aneurysm), and 1091 (86%) had TAA. Of those with TAA, 300 patients (27%) had chronic dissection and 109 (10%) had acute or subacute dissection. Associations of fragment concentrations with TAA (versus abdominal aortic aneurysm) or with dissection (versus no dissection) were estimated with odds ratios (OR) and 95% confidence intervals (CI) adjusted for age, sex, and smoking. Compared with controls, significantly higher percentages of aneurysm patients had detectable levels of fibrillin fragments. TAA was significantly more common (than abdominal aortic aneurysm) in the highest compared with lowest quartile of fibrillin-1 concentration (OR=2.9; 95% CI, 1.6-5.0). Relative to TAA without dissection, acute or subacute dissection (OR=2.9; 95% CI, 1.6-5.3), but not chronic dissection, was more frequent in the highest compared with lowest quartile of fibrillin-1 concentration. Neither TAA nor dissection was associated with fibrillin-2 or fibulin-4. CONCLUSIONS: Circulating fibrillin-1 fragments represent a new potential biomarker for TAA and acute aortic dissection.


Asunto(s)
Aneurisma de la Aorta Torácica/sangre , Aneurisma de la Aorta Torácica/epidemiología , Disección Aórtica/sangre , Disección Aórtica/epidemiología , Proteínas de Microfilamentos/sangre , Anciano , Aneurisma de la Aorta Abdominal/sangre , Aneurisma de la Aorta Abdominal/epidemiología , Biomarcadores/sangre , Estudios Transversales , Proteínas de la Matriz Extracelular/sangre , Femenino , Fibrilina-1 , Fibrilina-2 , Fibrilinas , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo
4.
J Histochem Cytochem ; 58(10): 903-15, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20855553

RESUMEN

Polycystic ovary syndrome (PCOS) is a common endocrinopathy in women of reproductive age. Although genetic linkage analyses have demonstrated a susceptibility locus for PCOS mapping to the fibrillin-3 gene, the presence of fibrillin proteins in normal and polycystic ovaries has not been characterized. This study compared and contrasted fibrillin-1, -2, and -3 localization in normal and polycystic ovaries. Immunohistochemical stainings of ovaries from 21 controls and 9 patients with PCOS were performed. Fibrillin-1 was ubiquitous in ovarian connective tissue. Fibrillin-2 localized around antral follicles and in areas of folliculolysis. Fibrillin-3 was present in a restricted distribution within the specialized perifollicular stroma of follicles in morphological transition from primordial to primary type [transitional follicles (TFs)]. Fibrillin-1 and -2 stainings of PCOS ovaries were similar to those of the controls. However, in eight of the nine PCOS ovaries, there was a decrease in the number of TFs associated with fibrillin-3, including no staining in five PCOS samples; decreased number of fibrillin-3-associated TFs/mm(2) was confirmed by quantitative analysis. Our findings support a role for fibrillin-3 in the pathogenesis of PCOS and suggest fibrillin-3 may function in primordial to primary follicle transition. We propose that loss of fibrillin-3 during folliculogenesis may be an important factor in PCOS pathogenesis.


Asunto(s)
Proteínas de Microfilamentos/metabolismo , Ovario/metabolismo , Síndrome del Ovario Poliquístico/metabolismo , Adolescente , Adulto , Femenino , Fibrilina-1 , Fibrilina-2 , Fibrilinas , Humanos , Persona de Mediana Edad , Folículo Ovárico/metabolismo , Células del Estroma/metabolismo , Adulto Joven
5.
Curr Med Chem ; 17(26): 2897-905, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20858171

RESUMEN

Platelets are indispensable for primary haemostasis, but their function needs to be tightly regulated to prevent excessive platelet activity, possibly leading to atherothrombotic events. An important mediator of the platelet activity is cyclic AMP (cAMP), which inhibits platelet aggregation. Intracellular cAMP levels are regulated via the Gs and Gi alpha subunits of heterotrimeric G proteins, which couple to adenylyl cyclase to respectively stimulate or inhibit cAMP production. Binding of a ligand to its G protein-coupled seven-transmembrane receptor activates these G proteins. In this review, we discuss a Gs-coupled receptor on platelets, VPAC1, and 2 important Gi-coupled receptors, the ADP receptor P2Y(12) and the prostaglandin E(2) receptor EP3. The regulation of platelet cAMP levels at the level of the receptors themselves or the G proteins coupled to them is analyzed. Alterations in Gsα and Giα function are associated with altered platelet reactivity. An increase in Gs function, or alternatively a defective Gi signaling, can be a risk factor for bleeding, while a loss of Gs function can result in a prothrombotic state. Regulator of G protein signaling (RGS) proteins accelerate the rate of inactivation of G protein-mediated signaling. One of the RGS proteins, RGS2, inhibits Gs signaling by interacting directly with adenylyl cyclase. The thienopyridine class of antiplatelet agents is based on cAMP-mediated regulation of platelet function through modification of the P2Y(12) receptor. Clopidogrel and some other novel cAMP regulators are discussed. Secondly, we review the use of prostacyclin derivatives to treat pulmonary arterial hypertension.


Asunto(s)
Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , AMP Cíclico/metabolismo , Inhibidores de Agregación Plaquetaria/farmacología , Inhibidores de Agregación Plaquetaria/uso terapéutico , Antagonistas del Receptor Purinérgico P2Y/farmacología , Antagonistas del Receptor Purinérgico P2Y/uso terapéutico , Clopidogrel , AMP Cíclico/sangre , Hipertensión Pulmonar Primaria Familiar , Humanos , Hipertensión Pulmonar/tratamiento farmacológico , Antagonistas del Receptor Purinérgico P2Y/química , Receptores Purinérgicos P2Y12/metabolismo , Receptores de Tipo I del Polipéptido Intestinal Vasoactivo/metabolismo , Transducción de Señal/efectos de los fármacos , Ticlopidina/análogos & derivados , Ticlopidina/química , Ticlopidina/farmacología
6.
J Biol Chem ; 284(25): 16872-16881, 2009 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-19349279

RESUMEN

Latent transforming growth factor (TGF) beta-binding proteins (LTBPs) interact with fibrillin-1. This interaction is important for proper sequestration and extracellular control of TGFbeta. Surface plasmon resonance interaction studies show that residues within the first hybrid domain (Hyb1) of fibrillin-1 contribute to interactions with LTBP-1 and LTBP-4. Modulation of binding affinities by fibrillin-1 polypeptides in which residues in the third epidermal growth factor-like domain (EGF3) are mutated demonstrates that the binding sites for LTBP-1 and LTBP-4 are different and suggests that EGF3 may also contribute residues to the binding site for LTBP-4. In addition, fibulin-2, fibulin-4, and fibulin-5 bind to residues contained within EGF3/Hyb1, but mutated polypeptides again indicate differences in their binding sites in fibrillin-1. Results demonstrate that these protein-protein interactions exhibit "exquisite specificities," a phrase commonly used to describe monoclonal antibody interactions. Despite these differences, interactions between LTBP-1 and fibrillin-1 compete for interactions between fibrillin-1 and these fibulins. All of these proteins have been immunolocalized to microfibrils. However, in fibrillin-1 (Fbn1) null fibroblast cultures, LTBP-1 and LTBP-4 are not incorporated into microfibrils. In contrast, in fibulin-2 (Fbln2) null or fibulin-4 (Fbln4) null cultures, fibrillin-1, LTBP-1, and LTBP-4 are incorporated into microfibrils. These data show for the first time that fibrillin-1, but not fibulin-2 or fibulin-4, is required for appropriate matrix assembly of LTBPs. These studies also suggest that the fibulins may affect matrix sequestration of LTBPs, because in vitro interactions between these proteins are competitive.


Asunto(s)
Proteínas de Unión al Calcio/metabolismo , Proteínas de la Matriz Extracelular/metabolismo , Proteínas de Unión a TGF-beta Latente/metabolismo , Proteínas de Microfilamentos/metabolismo , Animales , Sitios de Unión/genética , Unión Competitiva , Proteínas de Unión al Calcio/química , Proteínas de Unión al Calcio/deficiencia , Proteínas de Unión al Calcio/genética , Células Cultivadas , Proteínas de la Matriz Extracelular/química , Proteínas de la Matriz Extracelular/deficiencia , Proteínas de la Matriz Extracelular/genética , Fibrilina-1 , Fibrilinas , Humanos , Proteínas de Unión a TGF-beta Latente/genética , Ratones , Ratones Noqueados , Microfibrillas/metabolismo , Proteínas de Microfilamentos/química , Proteínas de Microfilamentos/deficiencia , Proteínas de Microfilamentos/genética , Estructura Terciaria de Proteína , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Resonancia por Plasmón de Superficie
7.
J Biol Chem ; 283(20): 13874-88, 2008 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-18339631

RESUMEN

Both latent transforming growth factor-beta (TGF-beta)-binding proteins fibrillins are components of microfibril networks, and both interact with members of the TGF-beta family of growth factors. Interactions between latent TGF-beta-binding protein-1 and TGF-beta and between fibrillin-1 and bone morphogenetic protein-7 (BMP-7) are mediated by the prodomain of growth factor complexes. To extend this information, investigations were performed to test whether stable complexes are formed by additional selected TGF-beta family members. Using velocity sedimentation in sucrose gradients as an assay, complex formation was demonstrated for BMP-7 and growth and differentiation factor-8 (GDF-8), which are known to exist in prodomain/growth factor complexes. Comparison of these results with complex formation by BMP-2, BMP-4 (full-length and shortened propeptides), BMP-10, and GDF-5 allowed us to conclude that all, except for BMP-2 and the short BMP-4 propeptides, formed complexes with their growth factors. Using surface plasmon resonance, binding affinities between fibrillin and all propeptides were determined. Binding studies revealed that the N-terminal end of fibrillin-1 serves as a universal high affinity docking site for the propeptides of BMP-2, -4, -7, and -10 and GDF-5, but not GDF-8, and located the BMP/GDF binding site within the N-terminal domain in fibrillin-1. Rotary shadowing electron microscopy of molecules of BMP-7 complex bound to fibrillin-1 confirmed these findings and also showed that prodomain binding targets the growth factor to fibrillin. Immunolocalization of BMP-4 demonstrated fibrillar staining limited to certain tissues, indicating tissue-specific targeting of BMP-4. These data implicate the fibrillin microfibril network in the extracellular control of BMP signaling and demonstrate differences in how prodomains target their growth factors to the extracellular space.


Asunto(s)
Proteínas Morfogenéticas Óseas/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Proteínas de Microfilamentos/metabolismo , Secuencia de Bases , Proteína Morfogenética Ósea 2 , Proteína Morfogenética Ósea 7 , Línea Celular Tumoral , Cartilla de ADN/química , Fibrilina-1 , Fibrilinas , Factor 5 de Diferenciación de Crecimiento , Humanos , Proteínas de Microfilamentos/química , Modelos Biológicos , Datos de Secuencia Molecular , Unión Proteica , Transducción de Señal , Resonancia por Plasmón de Superficie , Factor de Crecimiento Transformador beta/metabolismo
8.
Am J Med Genet A ; 143A(22): 2635-41, 2007 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-17937443

RESUMEN

Mutations involving elastic tissue proteins result in a broad spectrum of phenotypes affecting skin, skeleton, ocular and vascular structures, including tortuous blood vessels and cutis laxa. Here we report on a female newborn with apparently long fingers, aortic aneurysm, tortuous pulmonary arteries and mild generalized lax skin. She died at 27 days of age due to severe respiratory distress and inoperable systemic vascular abnormalities. Skin biopsy showed marked paucity and fragmentation of elastic fibers and autopsy revealed occlusion of the pulmonary artery. DNA analysis identified compound heterozygous mutations ((c.835C > T (p.R279C)/c.1070_1073dupCCGC) in fibulin-4, a recently recognized elastic fiber associated protein. Analyses of dermal fibroblasts from the patient indicated that fibulin-4 mRNAs with the 4-bp duplication transcribed from one allele are probably subject to nonsense-mediated decay, whereas synthesis and secretion of the missense R279C fibulin-4 protein from the other allele is severely impaired. Immunostaining demonstrated a total absence of fibulin-4 fibers in the extracellular matrix deposited by the patient's fibroblasts. Our studies provide evidence that deficiency in fibulin-4 leads to a perinatal lethal condition associated with elastic tissue abnormalities.


Asunto(s)
Aneurisma de la Aorta/genética , Aracnodactilia/genética , Arteriopatías Oclusivas/genética , Cutis Laxo/genética , Proteínas de la Matriz Extracelular/genética , Anomalías Múltiples , Aneurisma de la Aorta/etiología , Aracnodactilia/etiología , Arteriopatías Oclusivas/etiología , Cutis Laxo/etiología , Tejido Elástico/patología , Proteínas de la Matriz Extracelular/deficiencia , Resultado Fatal , Femenino , Heterocigoto , Humanos , Recién Nacido , Mutación , Arteria Pulmonar
9.
Appl Spectrosc ; 60(9): 994-1003, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17002824

RESUMEN

This investigation utilizes surface plasmon resonance (SPR) spectroscopy to detect and quantify human epidermal growth factor receptor 2 (HER-2), an oncogene product that is over-expressed in some aggressive forms of breast cancer. Specifically, the HER-2 trans-membrane protein p185 and its extra cellular fragment p105 are analytes targeted in this work by using a gold-based biosensor slide on which an anti-HER-2 antibody has been immobilized by attachment to Protein G that is fixed to the gold film. A detection limit of > or =11 ng/mL for p185 resulted when trastuzumab was used as the anti-HER-2 antibody on the biosensor slide. Experiments with semi-purified p105 revealed that it binds weakly and reversibly to trastuzumab, therefore complicating its detection and quantification. Results of studies that reacted a 13-amino-acid peptide (PP13) from the HER-2 kinase domain with its specific antibody were critically different than p185 and p105 studies. Spectral analysis of the reflectivity at constant bulk buffer refractive index revealed a progressive negative SPR shift over time. A negative shift suggests that a loss of protein mass from the anti-PP13 antibody-Protein G biosensor is occurring. Several possibilities that may explain these negative SPR shifts are discussed.


Asunto(s)
Receptor ErbB-2/análisis , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales Humanizados , Técnicas Biosensibles , Línea Celular Tumoral , Oro , Humanos , Inmunoensayo , Proteínas del Tejido Nervioso/química , Oligopéptidos/química , Unión Proteica , Estructura Terciaria de Proteína , Receptor ErbB-2/inmunología , Receptor ErbB-2/aislamiento & purificación , Proteínas Recombinantes/química , Resonancia por Plasmón de Superficie , Trastuzumab
10.
Appl Spectrosc ; 57(8): 906-14, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-14661832

RESUMEN

A multilayered biosensor was constructed and found to detect trinitrotoluene (TNT) in ppb concentrations in air both prior to and after detonation of TNT without use of a liquid phosphate buffered saline (PBS) superstrate. The biosensor surface was fabricated from a monoclonal antibody for TNT covalently bound to an 11,11'-dithio-bis(succinimidoylundecanoate) (DSU) self-assembled monolayer immobilized on a thin gold film bonded to a BK7 glass slide. The binding between the immobilized antibody and TNT antigen was detected using surface plasmon resonance spectroscopy (SPRS). Biosensor specificity for TNT was demonstrated with chemical homologues as well as against an unrelated explosive, RDX.


Asunto(s)
Contaminantes Atmosféricos/análisis , Oro/química , Inmunoensayo/instrumentación , Espectrometría Raman/métodos , Resonancia por Plasmón de Superficie/instrumentación , Trinitrotolueno/análisis , Anticuerpos/análisis , Anticuerpos/química , Gases/química , Inmunoensayo/métodos , Sensibilidad y Especificidad , Resonancia por Plasmón de Superficie/métodos , Trinitrotolueno/inmunología
11.
J Biol Chem ; 278(4): 2740-9, 2003 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-12429739

RESUMEN

Fibrillins are microfibril-forming extracellular matrix macromolecules that modulate skeletal development. In humans, mutations in fibrillins result in long bone overgrowth as well as other distinct phenotypes. Whether fibrillins form independent microfibrillar networks or can co-polymerize, forming a single microfibril, is not known. However, this knowledge is required to determine whether phenotypes arise because of loss of singular or composite functions of fibrillins. Immunolocalization experiments using tissues and de novo matrices elaborated by cultured cells demonstrated that both fibrillins can be present in the same individual microfibril in certain tissues and that both fibrillins can co-polymerize in fibroblast cultures. These studies suggest that the molecular information directing fibrillin fibril formation may be similar in both fibrillins. Furthermore, these studies provide a molecular basis for compensation of one fibrillin by the other during fetal life. In postnatal tissues, fibrillin-2 antibodies demonstrated exuberant staining in only one location: peripheral nerves. This surprising finding implicates distinct functions for fibrillin-2 in peripheral nerves, because a unique feature in humans and in mice mutant for fibrillin-2 is joint contractures that resolve over time.


Asunto(s)
Proteínas de Microfilamentos/biosíntesis , Proteínas de Microfilamentos/química , Animales , Anticuerpos Monoclonales/metabolismo , Línea Celular , Técnicas de Cocultivo , Ensayo de Inmunoadsorción Enzimática , Epítopos , Fibrilina-2 , Fibrilinas , Fibroblastos/metabolismo , Vectores Genéticos , Humanos , Immunoblotting , Ratones , Ratones Endogámicos BALB C , Microscopía Electrónica , Microscopía Fluorescente , Modelos Genéticos , Neuronas/metabolismo , Unión Proteica , Proteínas Recombinantes/metabolismo , Distribución Tisular , Células Tumorales Cultivadas
12.
Am J Manag Care ; 5(6 Suppl): S389-406, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10538851

RESUMEN

In the National Surgical Adjuvant Breast and Bowel Project P-1 Breast Cancer Prevention Trial (BCPT), women considered to be at high risk for developing breast cancer who received tamoxifen experienced 49% and 50% reductions in the risk of developing invasive and noninvasive breast cancer, respectively, compared with women receiving placebo. Although the BCPT addressed the clinical benefits of tamoxifen, this study sought to assess its cost effectiveness in the prevention of breast cancer in women at increased risk for developing the disease. Women were considered to be at an increased risk if they were: 1) 60 years of age or older, 2) age 35 to 59 years with a history of lobular carcinoma in situ, or 3) age 35 to 59 years with additional risk factors that made their 5-year predicted breast cancer risk at least as great as that of women 60 years of age. A decision-analysis model was used to estimate the incremental cost effectiveness of using tamoxifen compared with no intervention as preventive therapy in age-group defined cohorts of women who were at high risk for developing breast cancer. The analysis used data on the benefits and risks of tamoxifen as observed in the BCPT. In a subgroup analysis, tamoxifen's cost effectiveness was also evaluated in women who had had a hysterectomy, because of evidence that suggested an increased risk of endometrial cancer in women receiving tamoxifen. Under conservative assumptions from a base-case analysis, the incremental cost effectiveness of tamoxifen is $41,372 per life-year gained for women age 35 to 49 years, whereas for women age 50 to 59 years and 60 to 69 years, these values are $68,349 and $74,981, respectively. For women with a previous hysterectomy, tamoxifen's cost effectiveness is $46,060 per life-year gained. A strategy of using tamoxifen in high-risk women to prevent breast cancer in high-risk women may be cost effective, particularly in the 35-to-49 year-old age group and in those of any age who have had a hysterectomy.


Asunto(s)
Antineoplásicos Hormonales/economía , Antineoplásicos Hormonales/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/economía , Costos de la Atención en Salud/estadística & datos numéricos , Tamoxifeno/economía , Tamoxifeno/uso terapéutico , Antineoplásicos Hormonales/efectos adversos , Neoplasias de la Mama/epidemiología , Ensayos Clínicos como Asunto , Costo de Enfermedad , Análisis Costo-Beneficio , Costos de los Medicamentos , Femenino , Humanos , Factores de Riesgo , Tamoxifeno/efectos adversos , Resultado del Tratamiento , Estados Unidos
13.
Plant Mol Biol ; 31(5): 993-1008, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8843942

RESUMEN

The cDNAs encoding the seed antimicrobial peptides (AMPs) from Mirabilis jalapa (Mj-AMP2) and Amaranthus caudatus (Ac-AMP2) have previously been characterized and it was found that Mj-AMP2 and Ac-AMP2 are processed from a precursor preprotein and preproprotein, respectively [De Bolle et al., Plant Mol Biol 28:713-721 (1995) and 22:1187-1190 (1993), respectively]. In order to study the processing, sorting and biological activity of these antimicrobial peptides in transgenic tobacco, four different gene constructs were made: a Mj-AMP2 wild-type gene construct, a Mj-AMP2 mutant gene construct which was extended by a sequence encoding the barley lectin carboxyl-terminal propeptide, a known vacuolar targeting signal [Bednarek and Raikhel, Plant Cell 3: 1195-1206 (1991)]; an Ac-AMP2 wild-type gene construct; and finally, an Ac-AMP2 mutant gene construct which was truncated in order to delete the sequence encoding the genuine carboxyl-terminal propeptide. Processing and localization analysis indicated that an isoform of Ac-AMP2 with a cleaved-off carboxyl-terminal arginine was localized in the intercellular fluid fraction of plants expressing either wild-type or mutant gene constructs. Mj-AMP2 was recovered extracellularly in plants transformed with Mj-AMP2 wild-type gene construct, whereas an Mj-AMP2 isoform with a cleaved-off carboxyl-terminal arginine accumulated intracellularly in plants expressing the mutant precursor protein with the barley lectin propeptide. The in vitro antifungal activity of the AMPs purified from transgenic tobacco expressing any of the four different precursor proteins was similar to that of the authentic proteins. However, none of the transgenic plants showed enhanced resistance against infection with either Botrytis cinerea or Alternaria longipes.


Asunto(s)
Antifúngicos/metabolismo , Proteínas de Plantas/metabolismo , Secuencia de Aminoácidos , Antifúngicos/aislamiento & purificación , Antifúngicos/farmacología , Transporte Biológico , Compartimento Celular , Técnica del Anticuerpo Fluorescente , Immunoblotting , Pruebas de Sensibilidad Microbiana , Hongos Mitospóricos/efectos de los fármacos , Datos de Secuencia Molecular , Enfermedades de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/aislamiento & purificación , Proteínas de Plantas/farmacología , Plantas Modificadas Genéticamente , Plantas Tóxicas , Procesamiento Proteico-Postraduccional , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacología , Análisis de Secuencia , Distribución Tisular , Nicotiana/genética , Transformación Genética
14.
Biochem Int ; 26(5): 923-34, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1610391

RESUMEN

The effects of all-trans retinoic acid (RA) on the lipoprotein lipase (LPL) activity, synthesis and mRNA content in 3T3-L1 adipocytes were studied. When fully differentiated 3T3-L1 adipocytes were exposed to RA, dose-dependent suppression of LPL activity was observed. The loss of activity reached a maximum of 60% of the control level and appeared to be due to an effect on synthesis of the enzyme, as judged from the decreased incorporation of [35S] methionine and [35S] cysteine into immunoprecipitable LPL. The LPL mRNA level remained unchanged under the same conditions. In contrast, no significant reduction in glycerol-3-phosphate dehydrogenase activity or change in the morphological signature occurred on 24 hr exposure of 3T3-L1 adipocytes to RA. These results suggest that RA can specifically down-regulate LPL enzyme expression in adipocytes at the posttranscriptional level.


Asunto(s)
Tejido Adiposo/enzimología , Lipoproteína Lipasa/metabolismo , Tretinoina/farmacología , Tejido Adiposo/efectos de los fármacos , Animales , Línea Celular , Regulación hacia Abajo , Lipoproteína Lipasa/genética , Procesamiento Postranscripcional del ARN/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo
15.
Biochim Biophys Acta ; 1053(1): 43-8, 1990 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-2114181

RESUMEN

Lipoprotein lipase (LPL) (EC 3.1.1.34) hydrolyzes triacylglycerols of very low density lipoproteins and chylomicrons. It is produced by several cell types, including macrophages, which are frequent in atherosclerotic lesions. The atherosclerotic plaque also contains activated T lymphocytes. We therefore investigated the possible regulatory effect of the T lymphocyte-derived lymphokine interferon-gamma (IFN-gamma) on macrophage LPL. Human monocyte-derived macrophages were treated with recombinant IFN-gamma or conditioned medium from activated peripheral blood mononuclear cells for 3 days. LPL activity was thereafter measured in the culture medium and in cell homogenates. The enzyme protein was detected at a cellular level by immunocytochemistry and immunopredicipitation. Recombinant IFN-gamma caused a profound decrease in macrophage LPL secretion. The IFN-gamma-treated cells, however, still contained immunodetectable enzyme and the decrease in secretion was apparently only partly due to an inhibited synthesis. Conditioned medium from activated peripheral blood mononuclear cells also drastically decreased the macrophage LPL secretion. When the conditioned medium was treated with antibodies against IFN-gamma, its down-regulating effect on macrophage LPL was totally removed. The data indicate that IFN-gamma is inhibiting macrophage LPL at least in part via a reduction of LPL synthesis. A local release of IFN-gamma may be important in the pathogenesis of atherosclerosis by affecting the lipid accumulation in the lesion.


Asunto(s)
Interferón gamma/farmacología , Lipoproteína Lipasa/antagonistas & inhibidores , Macrófagos/enzimología , Monocitos/enzimología , Linfocitos T/metabolismo , Células Cultivadas , Técnica del Anticuerpo Fluorescente , Antígenos HLA-DR/metabolismo , Humanos , Técnicas de Inmunoadsorción , Lipoproteína Lipasa/metabolismo , Macrófagos/inmunología , Proteínas Recombinantes
16.
Kidney Int ; 35(5): 1111-8, 1989 May.
Artículo en Inglés | MEDLINE | ID: mdl-2549293

RESUMEN

Tumor necrosis factor (TNF) is a cytokine which is produced by mononuclear phagocytes upon activation by bacterial lipopolysaccharide (LPS) and various other stimuli. In immune-mediated glomerulonephritis, infiltration of glomeruli by monocytes-macrophages is associated with production of TNF. The purpose of the present experiments was to determine whether mesangial cells could also contribute to glomerular TNF synthesis. TNF activity has been determined in the culture medium of rat mesangial cells using a L-929 fibroblast lytic assay. This activity was detectable only when the cells were exposed to LPS (0.1 to 10 micrograms/ml) and for periods longer than one hour. The cytotoxic factor was identified as TNF since: (1) the lytic activity was completely inhibited by an anti-mouse TNF polyclonal antibody and was associated with suppression of lipoprotein lipase activity in adipocytes; (2) its molecular weight (110,000 daltons) corresponded to that observed for murine TNF under non-denaturing conditions; and (3) mRNA encoding TNF was expressed by mesangial cells two hours after addition of LPS. To assess the mechanisms whereby TNF production was regulated, the role of prostaglandin E2 (PGE2) was determined. LPS caused a dose-dependent increase of PGE2 synthesis by mesangial cells. Treatment by indomethacin promoted a suppression of PGE2 production together with an increase of TNF synthesis, indicating that PGE2 acted in a negative feedback manner to regulate the production of TNF. Addition of PGE2 (0.1 to 300 nM) or 8-bromo cyclic AMP (0.1 to 100 microM) induced similar dose-dependent reductions of TNF synthesis. Thus the inhibitory effect of PGE2 probably required in part cyclic AMP accumulation.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Mesangio Glomerular/metabolismo , Lipopolisacáridos/farmacología , Factor de Necrosis Tumoral alfa/biosíntesis , 8-Bromo Monofosfato de Adenosina Cíclica/farmacología , Animales , Northern Blotting , Células Cultivadas , Cromatografía en Gel , AMP Cíclico/biosíntesis , Dinoprostona/biosíntesis , Mesangio Glomerular/efectos de los fármacos , Corteza Renal/metabolismo , Cinética , Ratas , Ratas Endogámicas , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/aislamiento & purificación
17.
Biochim Biophys Acta ; 877(1): 112-20, 1986 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-3013314

RESUMEN

Cells isolated from newborn rat hearts were cultured for 10-14 days, and lipoprotein lipase activity was present in an intracellular and heparin-releasable pool. Treatment of the cultures with 10(-7) M isoproterenol for 3 min resulted in a 3-fold increase in heparin-releasable lipoprotein lipase and a concomitant decrease in residual cellular enzyme activity. Similar results were obtained by treatment with dibutyryl cAMP. Treatment with isoproterenol or dibutyryl cAMP for 2 h affected glycosylation of immunoadsorbable lipoprotein lipase, so that the ratio of [3H]galactose to [14C]mannose in the heparin-releasable enzyme increased from 3.8 (control) to 13.0 (isoproterenol-treated). The change in the ratio of the sugars in the cellular fraction of the enzyme was from 3.1 to 9.9. 2 h treatment with isoproterenol did not enhance new enzyme synthesis, as determined by incorporation of [3H]leucine into immunoadsorbable lipoprotein lipase. 24 h after addition of either isoproterenol or dibutyryl cAMP to the culture medium, stimulation of enzyme synthesis was demonstrated. The present results permit three effects of isoproterenol on lipoprotein lipase to be distinguished: stimulation of translocation from a cellular to heparin-releasable pool; enhanced processing of mannose residues and terminal glycosylation; stimulation of synthesis of enzyme protein.


Asunto(s)
Lipoproteína Lipasa/metabolismo , Miocardio/enzimología , Receptores Adrenérgicos beta/metabolismo , Animales , Animales Recién Nacidos , Bucladesina/farmacología , Células Cultivadas , Galactosa/metabolismo , Heparina/farmacología , Isoproterenol/farmacología , Leucina/metabolismo , Manosa/metabolismo , Ratas , Factores de Tiempo
19.
Arq. bras. cardiol ; 38(1): 55-8, 1982. ilus
Artículo en Portugués | LILACS | ID: lil-7407

RESUMEN

Descrevem-se dois casos de aneurisma arteriovenoso do pulmao, em pacientes do sexo feminino e com idades de 18 e 23 anos. As pacientes eram intensamente cianoticas, mas nao havia evidencia de cardiopatia congenita. O diagnostico, suspeitado pelo aspecto radiografico de multiplas opacificacoes saculares, foi confirmado atraves de angiografia pulmonar. As lesoes localizavam-se no lobo medio em um caso e, no lobo inferior esquerdo, no outro. Ambas as doentes foram tratadas com sucesso por lobectomia. Discutem-se os principais aspectos patologicos e clinicos dessa doenca


Asunto(s)
Arteria Pulmonar , Venas Pulmonares , Fístula Arteriovenosa
20.
Arq. bras. cardiol ; 38(1): 45-8, 1982.
Artículo en Portugués | LILACS | ID: lil-7405

RESUMEN

Descreve-se o caso de uma paciente de 12 anos de idade, portadora de insuficiencia mitral reumatica, que desenvolveu endocardite bacteriana por Staphylococcus aureus. A infeccao determinou a formacao de um aneurisma sacular do ventriculo esquerdo, chegando a romper-se no saco pericardico. Realizou-se uma operacao de emergencia na qual se substituiu a valva mitral e se reparou o aneurisma,mas a paciente faleceu devido a fibrinolise. A raridade e os principais aspectos clinicos e cirurgicos desta condicao sao discutidos


Asunto(s)
Aneurisma Infectado , Endocarditis Bacteriana
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