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1.
Breast Cancer Res Treat ; 205(2): 323-332, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38433127

RESUMEN

PURPOSE: Female breast cancer (BC) is the leading cause of cancer incidence and mortality in India, and accounted for 13.5% of new cancer cases and 10% of cancer-related deaths in 2020. This study aims to estimate and report the female BC burden in India at state level from 2012 to 2016 in terms of years of life lost, years lived with disability, and disability-adjusted life years (DALYs), and to project the burden for the year 2025. METHODS: The cancer incidence and mortality data from 28 population-based cancer registries were analysed. The mean mortality to incidence ratio was estimated, and mortality figures were adjusted for underreporting. The burden of female BC was estimated at national and subnational levels using Census data, World Health Organisation's lifetables, disability weights, and the DisMod-II tool. A negative binomial regression is employed to project burden for 2025. RESULTS: The burden of BC among Indian women in 2016 was estimated to be 515.4 DALYs per 100,000 women after age standardization. The burden metrics at state level exhibited substantial heterogeneity. Notably, Tamil Nadu, Telangana, Karnataka, and Delhi had a higher burden of BC than states in the eastern and north-eastern regions. The projection for 2025 indicates to a substantial increase, reaching 5.6 million DALYs. CONCLUSION: The female BC burden in India was significantly high in 2016 and is expected to substantially increase. Undertaking a multidisciplinary, context-specific approach for its prevention and control can address this rising burden.


Asunto(s)
Neoplasias de la Mama , Costo de Enfermedad , Sistema de Registros , Humanos , Femenino , India/epidemiología , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/mortalidad , Persona de Mediana Edad , Incidencia , Adulto , Anciano , Años de Vida Ajustados por Discapacidad , Años de Vida Ajustados por Calidad de Vida , Adulto Joven , Anciano de 80 o más Años
2.
Angew Chem Int Ed Engl ; 53(18): 4592-6, 2014 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-24677281

RESUMEN

A flexible metal-organic framework selectively sorbs para- (pX) over meta-xylene (mX) by synergic restructuring around pX coupled with generation of unused void space upon mX loading. The nature of the structural change suggests more generally that flexible structures which are initially mismatched in terms of fit and capacity to the preferred guest are strong candidates for effective molecular separations.

3.
Osteoarthritis Cartilage ; 18(8): 1051-7, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20417292

RESUMEN

OBJECTIVE: Small scale mechanical testing techniques offer new possibilities for defining changes in mechanical properties that accompany the morphological, histological, and biochemical abnormalities of osteoarthritis (OA). The goal of this study was to investigate the use of microindentation in characterizing the biphasic material properties of articular cartilage. Direct comparisons of the biphasic properties (E, k and nu) determined using microindentation were made to those determined on the same specimens using standard macroscale testing techniques. METHODS: Deep-zone bovine articular cartilage specimens (n=10) were tested in macroscale confined and unconfined compression. For microindentation testing, the biphasic properties were determined by conducting finite element simulations of the microindentation experiments for different combinations of values of biphasic properties and identifying the combination yielding the best match to each microindentation curve. Paired t-tests were performed to compare each of E, k and nu between the macro- and microscale. RESULTS: The microscale values for E, k and nu were 0.74 (0.53, 0.95)MPa, 0.66 (0.022, 0.110)x10(-16)m(4)/Ns, and 0.16 (0.08, 0.24), respectively. A significant difference between the macro- and microscale measurements was observed for k (P<0.0001), but not for E or nu (P=0.88, 0.16). CONCLUSIONS: The agreement in Young's modulus and Poisson's ratio between the results of the microindentation and macroscale tests supports the use of microindentation for characterization of some of the biphasic material properties of articular cartilage. The observed differences in permeability between macro- and microscales are consistent with evidence in the literature of a length-scale dependence to this property.


Asunto(s)
Cartílago Articular/fisiología , Fuerza Compresiva/fisiología , Estrés Mecánico , Animales , Fenómenos Biomecánicos , Bovinos , Elasticidad , Análisis de Elementos Finitos , Modelos Biológicos
4.
Phys Rev Lett ; 105(6): 066401, 2010 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-20867992

RESUMEN

When the complexity of a metallic compound reaches a certain level, a specific location in the structure may be critically responsible for a given fundamental property of a material while other locations may not play as much of a role in determining such a property. The first-principles theory has pinpointed a critical location in the framework of a complex intermetallic compound--Gd(5)Ge(4)--that resulted in a controlled alteration of the magnetism of this compound using precise chemical tools.

5.
J Cell Biol ; 71(3): 876-93, 1976 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-825523

RESUMEN

The localization of the chlorophyll-protein complexes inside the thylakoid membrane of Acetabularia mediterranea was determined by fractionating the chloroplast membrane with EDTA and Triton X-100, by using pronase treatment, and by labeling the surface-exposed proteins with 125I. The effects of the various treatments were established by electrophoresis of the solubilized membrane fractions and electron microscopy. After EDTA and pronase treatment, the membrane structure was still intact. Only the two chlorophyll-protein complexes of 67,000 and 152,000 daltons and an additional polypeptides were found in the membrane before the EDTA and pronase treatment. The 125,000 dalton complex seems to be buried inside the lipid layer. The 23,000 dalton subunit of the 67,000 dalton complex is largely exposed to the surface of the EDTA-insoluble membrane and only the chlorophyll-binding subunit of 21,500 daltons is buried inside the lipid layer.


Asunto(s)
Acetabularia/ultraestructura , Clorofila/análisis , Chlorophyta/ultraestructura , Cloroplastos/análisis , Proteínas de la Membrana/análisis , Proteínas de Plantas/análisis , Fraccionamiento Celular , Cloroplastos/efectos de los fármacos , Cloroplastos/ultraestructura , Ácido Edético/farmacología , Radioisótopos de Yodo , Membranas/ultraestructura , Mercaptoetanol , Modelos Biológicos , Polietilenglicoles , Pronasa/farmacología
6.
J Cell Biol ; 71(2): 624-38, 1976 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-993264

RESUMEN

We have investigated the structure of the photosynthetic membrane in a mutant of barley known to lack a chlorophyll-binding protein. This protein is thought to channel excitation energy to photosystem II, and is known as the "light-harvesting chlorophyll-protein complex." Extensive stacking of thylakoids into grana occurs in both mutant and wild-type chloroplasts. Examination of membrane internal structure by freeze-fracturing indicates that only slight differences exist between the fracture faces of mutant and wild-type membranes. These differences are slight reductions in the size of particles visible on the EFs fracture face, and in the number of particles seen on the PFs fracture face. No differences can be detected between mutant and wild-type on the etched out surface of the membrane. In contrast, tetrameric particles visible on the etched inner surface of wild-type thylakoids are extremely difficult to recognize on similar surfaces of the mutant. These particles can be recognized on inner surfaces of the mutant membranes when they are organized into regular lattices, but these lattices show a much closer particle-to-particle spacing than similar lattices in wild-type membranes. Although several interpretations of these data are possible, these observations are consistent with the proposal that the light-harvesting chlorophyll-protein complex of photosystem II is bound to the tetramer (which is visible on the EFs face as a single particle) near the inner surface of the membrane. The large tetramer, which other studies have shown to span the thylakoid membrane, may represent an assembly of protein, lipid, and pigment comprising all the elements of the photosystem II reaction. A scheme is presented which illustrates one possibility for the light reaction across the photosynthetic membrane.


Asunto(s)
Proteínas Portadoras/análisis , Clorofila , Cloroplastos/ultraestructura , Grano Comestible/ultraestructura , Hordeum/ultraestructura , Fotosíntesis , Proteínas de Plantas/análisis , Cloroplastos/análisis , Grabado por Congelación , Membranas/análisis , Membranas/ultraestructura , Mutación
7.
J Thromb Haemost ; 5(9): 1896-903, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17723129

RESUMEN

BACKGROUND: The plasma kallikrein-kinin system (PKKS) has been implicated in cardiovascular disease, but activation of the PKKS has not been directly probed in individuals at risk of coronary heart disease (CHD) or stroke. OBJECTIVE: To determine the involvement of the PKKS, including factor XI, in cardiovascular disease occurring in a nested case-control study from the Second Northwick Park Heart Study (NPHS-II). METHODS AND RESULTS: After a median follow-up of 10.7 years, 287 cases of CHD and stroke had been recorded and 542 age-matched controls were selected. When FXIIa-C1 esterase inhibitor (C1-inhibitor) concentrations were divided into tertiles (lowest tertile as reference), the odds ratios (ORs) at 95% CIs for CHD were 0.52 (0.34-0.80) in the middle tertile and 0.73 (0.49-1.09) in the highest tertile (P = 0.01 for the overall difference; P = 0.01 for CHD and stroke combined). For kallikrein-C1-inhibitor complexes, the ORs for stroke were 0.29 (0.12-0.72) and 0.67 (0.30-1.52) in the middle and high tertiles, respectively (P = 0.02). FXIIa-C1-inhibitor and kallikrein-C1-inhibitor complexes were negatively related to smoking and fibrinogen (P < 0.005). FXIa-inhibitor complexes correlated strongly with FXIIa-inhibitor complexes. CONCLUSIONS: Lower levels of inhibitory complexes of the PKKS enzymes and particularly of FXIIa contribute to the risk of CHD and stroke in middle-aged men. This observation supports the involvement of the PKKS in atherothrombosis.


Asunto(s)
Enfermedades Cardiovasculares/epidemiología , Sistema Calicreína-Quinina , Enfermedades Cardiovasculares/sangre , Estudios de Casos y Controles , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo
8.
Mol Cell Biol ; 1(1): 43-50, 1981 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-6100959

RESUMEN

The phosphorylation of a normal cellular protein of molecular weight 34,000 (34K) is enhanced in Rous sarcoma virus-transformed chicken embryo fibroblasts apparently as a direct consequence of the phosphotransferase activity of the Rous sarcoma virus-transforming protein pp60src. We have prepared anti-34K serum by using 34K purified from normal fibroblasts to confirm that the transformation-specific phosphorylation described previously occurs on a normal cellular protein and to further characterize the nature of the protein. In this communication, we also show that the phosphorylation of 34K is also increased in cells transformed by either Fujinami or PRCII sarcoma virus, two recently characterized avian sarcoma viruses whose transforming proteins, although distinct from pp60src, are also associated with phosphotransferase activity. Moreover, comparative fingerprinting of tryptic phosphopeptides shows that the major site of phosphorylation of 34K is the same in all three cases.


Asunto(s)
Virus del Sarcoma Aviar/genética , Transformación Celular Viral , Fosfoproteínas/biosíntesis , Animales , Virus del Sarcoma Aviar/metabolismo , Sitios de Unión , Genes Virales , Peso Molecular , Proteína Oncogénica pp60(v-src) , Fosforilación , Fosfotransferasas/genética , Fosfotransferasas/metabolismo , Proteínas de los Retroviridae/genética , Proteínas de los Retroviridae/metabolismo
9.
Biomech Model Mechanobiol ; 6(1-2): 13-20, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16715318

RESUMEN

Altered mechanical loading, secondary to biochemical changes in the nucleus pulposus, is a potential mechanism in disc degeneration. An understanding of the role of this altered mechanical loading is only possible by separating the mechanical and biological effects of early nucleus pulposus changes. The objective of this study was to quantify the mechanical effect of decreased glycosaminoglycans (GAG) and increased crosslinking in the nucleus pulposus using in vitro rat lumbar discs. Following initial mechanical testing the discs were injected according to the four treatment groups: PBS control, chondroitinase-ABC (ChABC) for GAG degradation, genipin (Gen) for crosslinking, or a combination of chondroitinase and genipin (ChABC+Gen). After treatment the discs were again mechanically tested, followed by histology or biochemistry. Neutral zone mechanical properties were changed by approximately 20% for PBS, ChABC, and ChABC+Gen treatments (significant only for PBS in a paired comparison). These trends were reversed with genipin crosslinking alone. With ChABC treatment the effective compressive modulus increased and the GAG content decreased; with the combination of ChABC+Gen the mechanics and GAG content were unchanged. Degradation of nucleus pulposus GAG alters disc axial mechanics, potentially contributing to the degenerative cascade. Crosslinking is unlikely to contribute to degeneration, but may be a potential avenue of treatment.


Asunto(s)
Reactivos de Enlaces Cruzados/farmacología , Glicosaminoglicanos/metabolismo , Disco Intervertebral/efectos de los fármacos , Disco Intervertebral/fisiología , Vértebras Lumbares/efectos de los fármacos , Animales , Fenómenos Biomecánicos , Condroitina ABC Liasa/metabolismo , Disco Intervertebral/metabolismo , Disco Intervertebral/patología , Glicósidos Iridoides , Iridoides/farmacología , Vértebras Lumbares/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley , Enfermedades de la Columna Vertebral/inducido químicamente , Enfermedades de la Columna Vertebral/metabolismo , Enfermedades de la Columna Vertebral/patología , Enfermedades de la Columna Vertebral/fisiopatología , Soporte de Peso/fisiología
10.
Circulation ; 111(3): 278-87, 2005 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-15655129

RESUMEN

BACKGROUND: Several studies have reported that the cholesteryl ester transfer protein (CETP) TaqIB gene polymorphism is associated with HDL cholesterol (HDL-C) levels and the risk of coronary artery disease (CAD), but the results are inconsistent. In addition, an interaction has been implicated between this genetic variant and pravastatin treatment, but this has not been confirmed. METHODS AND RESULTS: A meta-analysis was performed on individual patient data from 7 large, population-based studies (each >500 individuals) and 3 randomized, placebo-controlled, pravastatin trials. Linear and logistic regression models were used to assess the relation between TaqIB genotype and HDL-C levels and CAD risk. After adjustment for study, age, sex, smoking, body mass index (BMI), diabetes, LDL-C, use of alcohol, and prevalence of CAD, TaqIB genotype exhibited a highly significant association with HDL-C levels, such that B2B2 individuals had 0.11 mmol/L (0.10 to 0.12, P<0.0001) higher HDL-C levels than did B1B1 individuals. Second, after adjustment for study, sex, age, smoking, BMI, diabetes, systolic blood pressure, LDL-C, and use of alcohol, TaqIB genotype was significantly associated with the risk of CAD (odds ratio=0.78 [0.66 to 0.93]) in B2B2 individuals compared with B1B1 individuals (P for linearity=0.008). Additional adjustment for HDL-C levels rendered a loss of statistical significance (P=0.4). Last, no pharmacogenetic interaction between TaqIB genotype and pravastatin treatment could be demonstrated. CONCLUSIONS: The CETP TaqIB variant is firmly associated with HDL-C plasma levels and as a result, with the risk of CAD. Importantly, this CETP variant does not influence the response to pravastatin therapy.


Asunto(s)
Enfermedades Cardiovasculares/epidemiología , Proteínas Portadoras/genética , HDL-Colesterol/sangre , Glicoproteínas/genética , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Pravastatina/uso terapéutico , Enfermedades Cardiovasculares/prevención & control , Proteínas de Transferencia de Ésteres de Colesterol , Humanos , Polimorfismo Genético , Ensayos Clínicos Controlados Aleatorios como Asunto , Análisis de Regresión , Riesgo , Polimerasa Taq
11.
Cancer Res ; 47(13): 3589-94, 1987 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-3581089

RESUMEN

The recognized similarities between developing embryonic tissues and neoplastic cells have led to a number of experimental demonstrations which indicate that inductive microenvironments can alter the malignant phenotype. In postnatal life a morphogenetic cascade resembling endochondral bone development can be induced by s.c. implantation of demineralized diaphyseal bone matrix. We have examined the ability of this microenvironment to alter the phenotype of the transplantable Swarm rat chondrosarcoma in mixed implants. Neoplastic chondrocytes could be distinguished from host cells by nuclear morphometry since the nuclear area of the neoplastic chondrocytes was 2 to 3 times larger than that of comparable host-derived chondrocytes. Through the first 7 days post-implantation tumor cells in the presence of morphogenetically active matrix are morphologically indistinguishable from those implanted with morphogenetically inactivated matrix or implanted by themselves. With the advent of host cell chondrogenesis, however, adjacent neoplastic cells begin to undergo chondrolysis and calcification. Only those cells in the immediate proximity of host morphogenetic foci appear affected. An average of 26.7 +/- 7.0% (SD) of the implant surface areas examined revealed such changes. Chondrosarcoma cells implanted by themselves or in the presence of morphogenetically inactivated bone matrix underwent no such changes. These results suggest that factors released from host cells induced to undergo bone morphogenesis are capable of altering the differentiated phenotype of neoplastic cells.


Asunto(s)
Desarrollo Óseo , Matriz Ósea/fisiología , Cartílago/citología , Condrosarcoma/patología , Animales , Diferenciación Celular , Núcleo Celular/ultraestructura , Morfogénesis , Fenotipo , Ratas , Factores de Tiempo
12.
Cancer Res ; 61(19): 7122-9, 2001 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-11585744

RESUMEN

1alpha, 25-Dihydroxyvitamin D(3) [1alpha, 25-(OH)(2)D(3)] is recognized to have significant antiproliferative effects on certain prostatic carcinoma (PC) cell lines, although the precise mechanisms of action remain in question. We have evaluated the role of the cell cycle-dependent kinase inhibitor p21. In the PC cell lines ALVA-31 and LNCaP, 1alpha, 25-(OH)(2)D(3) inhibits growth and induces both p21 mRNA and protein levels. Growth inhibition of ALVA-31 cells was abolished by stable transfection with a p21 antisense construct. This effect was not attributable to a reduction in functional vitamin D receptors as measured by transcriptional activity with a luciferase-vitamin D response element reporter construct. Therefore, increased p21 expression appears necessary to mediate the antiproliferative effects of this hormone in ALVA-31 cells. Cell lines that are insensitive to the growth inhibitory properties of 1alpha, 25-(OH)(2)D(3) failed to up-regulate p21 expression after hormone treatment; these include sublines of ALVA-31 as well as the cell lines TSU-Pr1 and JCA-1. In the latter two lines, adenovirus-mediated expression of a sense p21 cDNA significantly reduced their proliferation as compared with a control adenoviral construct. This suggests that the signaling pathway downstream of p21 is intact in TSU-Pr1 and JCA-1 cells, although p21 expression appears unregulated by 1alpha, 25-(OH)(2)D(3). We propose a model in which the antiproliferative effect of 1alpha, 25-(OH)(2)D(3) on PC cells is mediated through increased p21 expression. Elucidation of why this effect is absent in select cell lines may provide valuable insight into the variability of responses observed in PC patients treated with vitamin D.


Asunto(s)
Calcitriol/farmacología , Ciclinas/biosíntesis , Inhibidores de Crecimiento/farmacología , Neoplasias de la Próstata/metabolismo , Recuento de Células , Ciclo Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Ciclinas/genética , ADN sin Sentido/genética , ADN sin Sentido/farmacología , Relación Dosis-Respuesta a Droga , Humanos , Masculino , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Transfección , Células Tumorales Cultivadas , Regulación hacia Arriba/efectos de los fármacos
13.
Cancer Res ; 61(17): 6340-4, 2001 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-11522622

RESUMEN

We have shown previously that the putative prostate carcinoma cell lines TSU-Pr1 and JCA-1 share a common origin. The observation that these cell lines have p53 and Ha-ras mutations identical to those in bladder carcinoma cell line T24 prompted us to investigate their possible interrelations. We used cytogenetics and DNA profiling to compare the genetic backgrounds of the three cell lines. At least 12 structural chromosomal abnormalities are shared between T24, TSU-Pr1, and JCA-1 cells. DNA profiles were identical for all three cell lines. These results clearly indicate that the cell lines TSU-Pr1 and JCA-1 are not of prostatic origin but are derivatives of the bladder carcinoma cell line T24. TSU-Pr1 and, to a lesser extent, JCA-1 are frequently used as models in prostate cancer research, and numerous publications have appeared based on these lines. Several other T24 cross-contaminants have been identified in the past, and some of these, such as ECV304, continue to be used under the wrong identity. Our findings highlight the insidious problem that can occur when information regarding cross-contamination does not reach individual researchers and/or the importance of the problem is not fully acknowledged.


Asunto(s)
Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/patología , Aberraciones Cromosómicas , ADN de Neoplasias/genética , Humanos , Cariotipificación , Masculino , Células Tumorales Cultivadas
14.
Cancer Res ; 60(23): 6730-6, 2000 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-11118059

RESUMEN

Fibroblast growth factor 8, isoform b (FGF8b), has been implicated in the oncogenesis of the prostate and mammary epithelia. We examined whether overexpression of FGF8b in a weakly tumorigenic prostate carcinoma cell line, LNCaP, could alter the growth and tumorigenic properties of these cells. LNCaP cells were infected with a lentivirus vector carrying FGF8b cDNA and the green fluorescent protein (GFP) cDNA in the same construct, and the infected cell population was sorted on the basis of GFP protein expression. It was demonstrated that, in comparison with the cells transduced with GFP-vector alone, LNCaP cells with FGF8b-GFP expression manifested an increased growth rate, higher soft agar clonogenic efficiency, enhanced in vitro invasion, and increased in vivo tumorigenesis. Most strikingly, whereas parental or vector-control LNCaP cells failed to grow at all in an in vivo tumorigenesis/diaphragm invasion assay in nude mice, the cells overexpressing FGF8b proliferated as deposits of tumor cells on the diaphragm, frequently with indications of tumor cell invasion into the diaphragm. Coculturing of primary prostatic or non-prostatic stromal cells with the infected LNCaP cells led us to observe that: (a) stromal cells, irrespective of tissue origin, strongly suppressed LNCaP cell growth; (b) FGF8b producing LNCaP cells could partially evade the stromal inhibition, perhaps from the autocrine stimulatory effect of FGF8b; and (c) production of FGF8b in the coculture had a stimulatory effect on the proliferation of the stromal cells, prostatic or non-prostatic. This stimulation was not attributable to the direct action of FGF8b on stromal cells. Instead, it appears that epithelial-stromal cell-cell contact and some unknown soluble factors secreted by LNCaP cells upon stimulation of FGF8b are required for the maximal effect. Together, these results suggest that the growth rate and biological behavior of prostatic cancer cells can be altered to a more aggressive phenotype by up-regulation of FGF8b expression. These changes in phenotype also influence the interaction of the affected cells with stromal cells. The data obtained may have direct relevance to the progression of prostate cancer, recognizing that FGF8b is naturally overexpressed in advanced disease.


Asunto(s)
Comunicación Celular/fisiología , Factores de Crecimiento de Fibroblastos/fisiología , Neoplasias de la Próstata/patología , Células 3T3 , Animales , División Celular/fisiología , Supervivencia Celular/fisiología , Técnicas de Cocultivo , Células Epiteliales/patología , Factor 8 de Crecimiento de Fibroblastos , Factores de Crecimiento de Fibroblastos/biosíntesis , Factores de Crecimiento de Fibroblastos/genética , Vectores Genéticos , Humanos , Lentivirus/genética , Masculino , Ratones , Ratones Desnudos , Proteínas de Neoplasias , Próstata/citología , Neoplasias de la Próstata/genética , Isoformas de Proteínas , Células del Estroma/citología , Transducción Genética
15.
Cancer Res ; 52(3): 515-20, 1992 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-1370648

RESUMEN

The LNCaP prostatic carcinoma cell line was examined for the presence of specific receptors for 1 alpha,25-dihydroxyvitamin D3 [1 alpha,25-(OH)2D3]. Whole cell binding studies identified approximately 2500 high-affinity (Kd = 1.4 x 10(-9) binding sites per cell. Competition studies revealed that these receptors are specific for the 1 alpha,25(OH)2 metabolite. Binding studies using the synthetic androgen R1881 indicate that separate androgen and vitamin D3 receptors exist in LNCaP cells. The vitamin D3 receptors sediment at approximately 3.5S on linear sucrose gradients. The sedimentation coefficient could be shifted with a monoclonal anti-vitamin D3 receptor antibody (9A7 gamma) but not with a monoclonal antibody to the androgen receptor (AN1-15). The receptor/ligand complex elutes from native DNA cellulose at 0.2 M KCl. Northern blot analysis identified an mRNA of approximately 4.6 kilobases which hybridized with a specific vitamin D3 receptor complementary DNA probe (hVDR). In the absence of androgens, 1 alpha,25(OH)2D3 stimulated growth and prostate-specific antigen production by LNCaP cells in a dose-dependent fashion. Dose-response curves indicated that at physiological concentrations (10(-9) M) 1 alpha,25(OH)2D3 was mitogenic, whereas at higher concentrations (10(-8) M) it promotes differentiation. These studies suggest that 1 alpha,25(OH)2D3 could play an important role in the natural history of and response to hormone therapy by prostatic cancer.


Asunto(s)
Calcitriol/metabolismo , Receptores de Esteroides/metabolismo , Anticuerpos Monoclonales , Antígenos de Neoplasias/análisis , Unión Competitiva , Biomarcadores de Tumor/análisis , Calcitriol/farmacología , División Celular/efectos de los fármacos , Línea Celular , Centrifugación por Gradiente de Densidad , Cromatografía de Afinidad , Citosol/metabolismo , Relación Dosis-Respuesta a Droga , Humanos , Cinética , Masculino , Metribolona/metabolismo , Antígeno Prostático Específico , Neoplasias de la Próstata , Receptores Androgénicos/metabolismo , Receptores de Calcitriol , Receptores de Esteroides/aislamiento & purificación
16.
Cancer Res ; 50(21): 7068-76, 1990 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-2170015

RESUMEN

To determine the role of lung cancer tumor imaging with monoclonal antibodies directed against high molecular weight human milk fat globule antigens, we administered i.v. 111In-KC-4G3 to 24 patients with advanced non-small cell lung cancer. One mg of 111In-KC-4G3 was mixed with 0, 9, 49, 99, or 499 mg of unlabeled KC-4G3 and infused i.v. over 1 to 5 h. The mean 111In-KC-4G3 radiochemical purity was greater than 97% and the resultant immunoreactivity averaged 62%. Successful imaging of cancer sites was accomplished in 92% of 24 patients, and 57% of 91 total lesions were visualized. Successful localization of tumor sites related to size (P less than 0.001), with 81% of lesions greater than 3.0 cm in diameter, 50% of lesions 1.5 to 3 cm, and 6% of lesions less than 1.5 cm successfully imaging, and to location (P less than 0.05), with 69% of pulmonary lesions, 80% of soft tissue lesions, and only 32% of bone metastases being visualized. Nonspecific reticulo-endothelial uptake of radioactivity was a major problem. Approximately 35% of 111In was chelated to serum transferrin by 24 and 48 h after infusion. The mean t 1/2 beta for plasma radioisotope and immunoreactive KC-4G3 was 29 and 27 h, respectively. There was no correlation between total infused antibody dose and imaging success or between total dose and effect on 111In and KC-4G3 kinetics. Circulating free KC-4 antigen was measurable in all but one patient before study. Tumor biopsy following infusion could demonstrate antibody presence but not saturable antigen binding. We conclude that (a) 111In-KC-4G3 demonstrates successful tumor localization in non-small cell lung cancers bearing generally high expression of its antigen and (b) further investigations to diminish nonspecific radioactivity for imaging and utilization of high dose radiolabeled antibody for therapeutic intent are warranted.


Asunto(s)
Anticuerpos Monoclonales , Antígenos/inmunología , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Neoplasias Pulmonares/diagnóstico por imagen , Anticuerpos Monoclonales/farmacocinética , Anticuerpos Monoclonales/toxicidad , Quelantes/metabolismo , Grasas , Cámaras gamma , Humanos , Inmunohistoquímica , Radioisótopos de Indio/farmacocinética , Radioisótopos de Indio/toxicidad , Leche Humana/inmunología , Ácido Pentético/metabolismo , Ácido Pentético/farmacocinética , Ácido Pentético/toxicidad , Cintigrafía
17.
Cancer Res ; 58(14): 3116-31, 1998 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-9679980

RESUMEN

BAG-1 is a multifunctional protein that blocks apoptosis and interacts with several types of proteins, including Bcl-2 family proteins, the kinase Raf-1, certain tyrosine kinase growth factor receptors, and steroid hormone receptors, possibly by virtue of its ability to regulate the Hsp70/Hsc70 family of molecular chaperones. Two major forms of the human and mouse BAG-1 proteins were detected by immunoblotting. The longer human and mouse BAG-1 proteins (BAG-1L) appear to arise through translation initiation at noncanonical CTG codons located upstream of and in-frame with the usual ATG codon used for production of the originally described BAG-1 protein. Immunoblotting experiments using normal tissues revealed that BAG-1L is far more restricted in its expression and is present at lower levels than the more prevalent BAG-1 protein. Human but not mouse tissues also produce small amounts of an additional isoform of BAG-1 of intermediate size (BAG-1M) that probably arises through translation initiation at yet another site involving an ATG codon. All three isoforms of human BAG-1 (BAG-1, BAG-1M, and BAG-1L) retained the ability to bind Hsc70. Subcellular fractionation and immunofluorescence confocal microscopy studies indicated that BAG-1L often resides in the nucleus, consistent with the presence of a nuclear localization sequence in the NH2-terminal unique domain of this protein. In immunohistochemical assays, BAG-1 immunoreactivity was detected in a wide variety of types of cells in normal adult tissues and was localized to either cytosol, nucleus, or both, depending on the particular type of cell. In some cases, cytosolic BAG-1 immunostaining was clearly associated with organelles resembling mitochondria, consistent with the reported interaction of BAG-1 with Bcl-2 and related proteins. Furthermore, experiments using a green fluorescence protein (GFP)-BAG-1 fusion protein demonstrated that overexpression of Bcl-2 in cultured cells can cause intracellular redistribution of GFP-BAG-1, producing a membranous pattern typical of Bcl-2 family proteins. The BAG-1 protein was found at high levels in several types of human tumor cell lines among the 67 tested, particularly leukemias, breast, prostate, and colon cancers. In contrast to normal tissues, which only rarely expressed BAG-1L, tumor cell lines commonly contained BAG-1L protein, including most prostate, breast, and leukemia cell lines, suggesting that a change in BAG-1 mRNA translation frequently accompanies malignant transformation.


Asunto(s)
Proteínas Portadoras/genética , ARN Mensajero/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Proteínas Portadoras/inmunología , Proteínas Portadoras/metabolismo , Núcleo Celular/metabolismo , Núcleo Celular/ultraestructura , Codón Iniciador/genética , Proteínas de Unión al ADN , Genes bcl-2/fisiología , Proteínas HSP70 de Choque Térmico/metabolismo , Humanos , Inmunohistoquímica , Ratones , Mitocondrias/metabolismo , Datos de Secuencia Molecular , Orgánulos/metabolismo , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Distribución Tisular , Factores de Transcripción , Células Tumorales Cultivadas/patología
18.
Biochim Biophys Acta ; 459(2): 145-56, 1977 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-836815

RESUMEN

The freeze-fracturing technique has been used to investigate membrane architecture in the mesophyll and bundle sheath chloroplasts of Zea mays. The structural organization of mesophyll chloroplasts is virtually identical to that of other species of higher plants which have been investigated with this technique. Characteristic distributions of particles of various sizes are seen on each fracture face after membrane splitting during the fracturing process, and these distributions indicate the differentiation of the membrane system into sacked (grana) and unstacked (stroma) regions, typical of grana-containing chloroplasts. Bundle sheath chloroplasts contain very few grana, and the thylakoids of these plastids are therefore largely unstacked. Analysis of artificially unstacked mesophyll chloroplasts indicates that this difference is not merely related to the presence or absence of adhesion between adjacent thylakoids, but reflects a substantial difference in membrane substructure between mesophyll and bundle sheath photosynthetic membranes. Bundle sheath thylakoids contain virtually the same number of small (P fracture face) particles as mesophyll thylakoids, but contain only 40% as many of the larger (E fracture face) tetrameric particles. These differences, together with biochemical data indicating the comparative deficiency of bundle sheath chloroplasts in Photosystem II activity, suggest that the E face particles are related to the presence or absence of Photosystem II activity.


Asunto(s)
Cloroplastos/ultraestructura , Fotosíntesis , Membrana Celular/ultraestructura , Técnica de Fractura por Congelación , Microscopía Electrónica , Plantas , Zea mays
19.
Circulation ; 102(17): 2058-62, 2000 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-11044420

RESUMEN

BACKGROUND: The relations of plasma activated factor XII (FXIIa) concentration and a common polymorphism (C46T) of the factor XII gene with hemostatic status and risk of coronary heart disease (CHD) were examined by prospective surveillance. METHODS AND RESULTS: Genotyping for the C46T variant was performed in 2624 men 50 to 61 years of age who were free of CHD at baseline. The genotype distribution was as follows: CC, 56.7%; CT; 36.9%; and TT, 6.6%. Plasma FXIIa was measured by ELISA on 1745 samples collected 1 year after baseline; median levels were (ng/mL) CC, 2.0; CT, 1.4; and TT, 0.8 (P:<0.0001). Respective values for plasma fibrinopeptide A (FPA, nmol/L) were 1.52, 1.35, and 1.15 (P:<0.0001); for factor VII coagulant activity (FVIIc, % standard), 114.5, 116.2, and 109.3 (P:=0.02). Group differences in FVIIc were unchanged by adjustment for body mass index and serum triglycerides. Whereas CHD incidence did not differ significantly by genotype, rates (per 1000 person-years) by thirds of FXIIa distribution were for <1.5 ng/mL, 7. 2; for 1.5 to 2.0 ng/mL, 7.2; and for >2.0 ng/mL, 13.6. Respective hazard ratios with the low third as reference group were 1.01 and 1. 96 (P:=0.007), which were essentially unchanged after allowance for genotype, blood lipids, blood pressure, body mass index, FVIIc, and FPA. CONCLUSIONS: The C46T polymorphism is a determinant of FXIIa, FPA, and possibly FVIIc, suggesting that FXII influences the activity state of the coagulation pathway and FPA cleavage from fibrinogen in vivo. Plasma FXIIa is increased in middle-aged men at high risk of CHD.


Asunto(s)
Enfermedad Coronaria/metabolismo , Factor VII/metabolismo , Factor XIIa/metabolismo , Fibrinopéptido A/metabolismo , Biomarcadores , Enfermedad Coronaria/diagnóstico , Enfermedad Coronaria/epidemiología , Enfermedad Coronaria/genética , Factor VII/genética , Factor XIIa/genética , Fibrinopéptido A/genética , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo Genético , Estudios Prospectivos , Factores de Riesgo
20.
Circulation ; 102(23): 2816-22, 2000 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-11104738

RESUMEN

BACKGROUND: This study sought to assess whether novel markers of hemostatic activity are predictive of coronary heart disease (CHD) and improve risk assessment. METHODS AND RESULTS: Conventional CHD risk factors, the activation peptides of factor IX and factor X, factor VII activity and antigen, activated factor XII, prothrombin fragment 1+2, fibrinopeptide A, and fibrinogen were measured in 1153 men aged 50 to 61 years who were free of myocardial infarction at recruitment. Activated factor VII (VIIa) was measured in 829 men. During 7.8 years of follow-up, 104 had a CHD event. Baseline status was related to outcome by logistic regression by using a modified nested case-control design. Screening performance was judged from receiver operating characteristic curves. A high activated factor XII was associated with increased CHD risk, but low levels were not protective. Plasma VIIa and factor X activation peptide were independently and inversely related to risk. Plasma factor IX activation peptide and fibrinogen were positively associated with risk, but the relations were no longer statistically significant after adjustment for other factors, including VIIa and apoA-I. Other hemostatic markers were not associated with CHD risk. CONCLUSIONS: Hemostatic status did not add significant predictive power to that provided by conventional CHD risk factors yet was able to substitute effectively for these factors.


Asunto(s)
Factores de Coagulación Sanguínea/análisis , Enfermedad Coronaria/diagnóstico , Biomarcadores/sangre , Enfermedad Coronaria/sangre , Enfermedad Coronaria/epidemiología , Factor IXa/análisis , Factor VIIa/análisis , Factor Xa/análisis , Fibrinógeno/análisis , Estudios de Seguimiento , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Curva ROC , Análisis de Regresión , Medición de Riesgo , Factores de Riesgo
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