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1.
Perfusion ; 30(6): 495-8, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25526731

RESUMEN

Over the past several decades, techniques for surgery of the aortic arch have undergone significant evolution. In addition, there have been refinements in the mechanism of cerebral protection utilized intraoperatively. However, significant practice variations in the strategy of antegrade selective cerebral perfusion continue to persist. Here, we describe a simple and easily reproducible technique for selective antegrade cerebral perfusion, utilizing axillary cannulation and retrograde coronary sinus balloon catheters.


Asunto(s)
Cateterismo Cardíaco/métodos , Catéteres Cardíacos , Circulación Cerebrovascular , Humanos
2.
Fish Shellfish Immunol ; 34(5): 1170-7, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23422813

RESUMEN

Cytokine responses in the Japanese pufferfish (Takifugu rubripes) head kidney (HK) cells to heat-killed lactic acid bacteria probiotics isolated from the Mongolian dairy products were investigated by transcriptomic examination. The HK cells were incubated with two heat-killed bacteria, namely Lactobacillus paracasei spp. paracasei (strain 06TCa22) and L. plantarum (strain 06CC2) and the responses of 16 cytokine genes at 0 (control), 1, 4, 8, 12, 24 and 48 h post-stimulation were assayed by multiplex RT-PCR analysis (GenomeLab Genetic Analysis System, GeXPS; Beckman Coulter, Inc.). The 16 genes included in the assay were pro-inflammatory cytokines (IL-1ß, IL-6, IL-17A/F-3, TNF-α and TNF-N), cell-mediated immune regulators (IL-12p35, IL-12p40 and IL-18), antiviral (I-IFN-1 and IFN-γ) and other regulatory (IL-2, IL-7, IL-15, IL-21, IL-10 and TGF-ß1) cytokines. Despite the differences in the transcriptional profiles, expression of all the cytokines tested here was significantly elevated by both the probiotic bacterial stimulants compared with the unstimulated control. Therefore, this in vitro study has demonstrated the modulation of cytokine defense mechanisms in the HK cells by the two heat-killed probiotics indicating their potentiality as novel immunostimulants to fish. However, strain-dependent varied expression of important cytokines (cell-mediated immune regulators, antiviral and anti-inflammatory cytokines) suggests better efficacy of L. paracasei spp. paracasei strain as fish immunostimulant. Further in vivo studies to elucidate the cytokine regulation networks will validate our present observations. A careful evaluation of ant-inflammatory properties may be undertaken using single strain to affirm the immunostimulatory capability. Moreover, application timings and frequency to assess the longevity of immunostimulant effects and to make the application cost-effective need to be evaluated before any practical use in aquaculture.


Asunto(s)
Citocinas/genética , Riñón Cefálico/inmunología , Lactobacillus/inmunología , Probióticos/administración & dosificación , Takifugu/genética , Takifugu/inmunología , Animales , Acuicultura , Citocinas/metabolismo , Productos Lácteos/análisis , Riñón Cefálico/efectos de los fármacos , Riñón Cefálico/metabolismo , Calor , Mongolia , Reacción en Cadena de la Polimerasa Multiplex/veterinaria , Especificidad de la Especie , Takifugu/metabolismo , Factores de Tiempo
3.
Nat Med ; 1(1): 53-8, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7584953

RESUMEN

The clinical use of fetal neural grafts as an intracerebral source of dopamine for patients with Parkinson's disease has met with limited success. Since basic fibroblast growth factor (bFGF) enhances the survival and growth of dopaminergic neurons in vitro, we explored whether cells genetically modified to produce bFGF would improve the functional efficacy of dopaminergic neurons implanted into rats with experimental Parkinson's disease. Results show that bFGF-producing cells grafted together with fetal dopamine neurons have potent growth-promoting effects on the implanted neurons in vivo. Moreover, rats implanted with such co-grafts display the most pronounced behavioural improvements post-grafting. These findings not only provide insight into the function of bFGF in situ, but also suggest an approach for enhancing the survival and function of dopamine neurons grafted into the damaged brain.


Asunto(s)
Dopamina/fisiología , Factor 2 de Crecimiento de Fibroblastos/farmacología , Mesencéfalo/trasplante , Animales , Conducta Animal/fisiología , Modelos Animales de Enfermedad , Femenino , Fibroblastos/citología , Supervivencia de Injerto/efectos de los fármacos , Enfermedad de Parkinson/terapia , Ratas , Ratas Endogámicas F344 , Transfección
4.
J Exp Med ; 166(3): 725-43, 1987 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-2442289

RESUMEN

We demonstrate here that T cell receptor for antigen (TCR)-triggered exocytosis in cytotoxic T lymphocytes (CTL) is not constitutive and is regulated through crosslinking of the TCR by antigen or monoclonal anti-TCR antibodies. Morphological and biochemical data using three different biochemical markers of granules and Percoll gradient fractionation analysis are presented, suggesting that TCR-triggered exocytosis is accompanied by the loss of granules from CTL and appearance of intragranular proteins and enzymatic activities in the incubation medium. The strict requirement for crosslinking of the TCR in exocytosis triggering could be bypassed by protein kinase C activators (phorbol esters or bryostatin I and II) acting in synergy with Ca2+ ionophores. It is shown that external Ca2+ is obligatory for both the TCR-triggered and for the PMA/A23187-triggered exocytosis, since Ca2+ chelators and divalent cations that compete with Ca2+ for A23187 can inhibit exocytosis of granules. These data suggest that Ca2+ from intracellular stores is not sufficient to support exocytosis in CTL. Ca2+ channel blockers and calmodulin antagonists significantly inhibited TCR-triggered exocytosis without affecting the basal level of secretion. The described results are consistent with a model in which exocytosis of granules in CTL is triggered by the crosslinking of TCR, transmembrane protein kinase C activation, and external Ca2+ translocation through CTL plasma membrane Ca2+ channels and modulation of activity of Ca2+, calmodulin-dependent enzymes, and cytoskeletal proteins.


Asunto(s)
Exocitosis , Receptores de Antígenos de Linfocitos T/inmunología , Serina Endopeptidasas , Linfocitos T Citotóxicos/inmunología , Animales , Anticuerpos Monoclonales , Calcimicina/farmacología , Calcio/fisiología , Bloqueadores de los Canales de Calcio/farmacología , Calmodulina/antagonistas & inhibidores , Calmodulina/fisiología , Centrifugación por Gradiente de Densidad , Gránulos Citoplasmáticos/enzimología , Gránulos Citoplasmáticos/inmunología , Endopeptidasas/inmunología , Endopeptidasas/metabolismo , Activación Enzimática/efectos de los fármacos , Exocitosis/efectos de los fármacos , Glucuronidasa/metabolismo , Granzimas , Canales Iónicos/fisiología , Isoflurofato , L-Lactato Deshidrogenasa/metabolismo , Ratones , Proteína Quinasa C/metabolismo , Acetato de Tetradecanoilforbol/farmacología
5.
J Exp Med ; 188(2): 267-76, 1998 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-9670039

RESUMEN

We have previously shown that uncharacterized glycoprotein VI (GPVI), which is constitutively associated and coexpressed with Fc receptor gamma chain (FcRgamma) in human platelets, is essential for collagen-stimulated tyrosine phosphorylation of FcRgamma, Syk, and phospholipase Cgamma2 (PLCgamma2), leading to platelet activation. Here we investigated involvement of the Src family in the proximal signals through the GPVI-FcRgamma complex, using the snake venom convulxin from Crotalus durissus terrificus, which specifically recognizes GPVI and activates platelets through cross-linking GPVI. Convulxin-coupled beads precipitated the GPVI-FcRgamma complex from platelet lysates. Collagen and convulxin induced tyrosine phosphorylation of FcRgamma, Syk, and PLCgamma2 and recruited tyrosine-phosphorylated Syk to the GPVI-FcRgamma complex. Using coprecipitation methods with convulxin-coupled beads and antibodies against FcRgamma and the Src family, we showed that Fyn and Lyn, but not Yes, Src, Fgr, Hck, and Lck, were physically associated with the GPVI-FcRgamma complex irrespective of stimulation. Furthermore, Fyn was rapidly activated by collagen or cross-linking GPVI. The Src family-specific inhibitor PP1 dose-dependently inhibited collagen- or convulxin-induced tyrosine phosphorylation of proteins including FcRgamma, Syk, and PLCgamma2, accompanied by a loss of aggregation and ATP release reaction. These results indicate that the Src family plays a critical role in platelet activation via the collagen receptor GPVI-FcRgamma complex.


Asunto(s)
Plaquetas/metabolismo , Glicoproteínas de Membrana Plaquetaria/metabolismo , Receptores Fc/metabolismo , Transducción de Señal , Familia-src Quinasas/metabolismo , Humanos , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-fyn , Agregación de Receptores
6.
J Clin Invest ; 55(6): 1337-48, 1975 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1133178

RESUMEN

Studies on peripheral metabolism of simultaneously administered 125-I-labeled L-thyroxine ([125-I]T4) and 131-I labeled L-trilodothyronine ([131-I]T3) were performed in five normal subjects, in four patients with untreated hypothyroidism, and in 3 hypothyroid patients made euthyroid by the administration of T4. The fractional turnover rate (lambda 03) of thyroid hormones irreversibly leaving the site of degradation and the volumes of pool 1 (serum V1) of pool (interstitial fluid, V2), and of pool 3 (all tissues, V3)were obtained by using a three-compartment analysis. In addition to the turnover studies, the ratios for the in vivo T4 to T3 conversion were determined by paper chromatographic study in sera obtained 4, 7, and 10 daysafter the injection. The rate (K12) of the extrathyroidal conversion of T4 to T3 was also estimated by the compartment analysis. The T3 distribution volume (V3) of pool 3, in which T3 is utilized and degraded, was about 60% of totaldistribution volume (V=V1+V2+V3) in normal subjects, whereas only about 25% of the extrathyroidal T4 pool was in the intracellular compartment, indicating that T3 is predominantly an intracellular hormone..


Asunto(s)
Hipotiroidismo/metabolismo , Tiroxina/metabolismo , Triyodotironina/metabolismo , Adulto , Cromatografía en Papel , Femenino , Humanos , Hipotiroidismo/sangre , Radioisótopos de Yodo , Masculino , Persona de Mediana Edad , Modelos Biológicos , Trazadores Radiactivos/sangre , Tiroxina/sangre , Triyodotironina/sangre
7.
J Natl Cancer Inst ; 93(22): 1739-46, 2001 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-11717335

RESUMEN

BACKGROUND: Dexamethasone, a synthetic glucocorticoid, has clinical benefit in patients with hormone-refractory prostate cancer (HRPC), but the mechanisms responsible for its effects are unknown. The nuclear factor-kappaB (NF-kappaB)-dependent cytokine interleukin (IL) 6 (IL-6) is thought to stimulate growth of HRPC. Because dexamethasone interferes with NF-kappaB activation, we determined whether dexamethasone inhibits prostate cancer growth by working through the glucocorticoid receptor (GR) to interfere with NF-kappaB-IL-6 pathway. METHODS: Three human prostate cancer cell lines (DU145, PC-3, and LNCaP) were assessed for GR expression and responsiveness to dexamethasone. Levels of GR, NF-kappaB, and the cytoplasmic NF-kappB inhibitor IkappaBalpha were determined by western blotting and of IL-6 by enzyme immunoassay. The subcellular localization of NF-kappaB was analyzed by immunofluorescence. The effects of dexamethasone (thrice weekly injections of 1 microg/mouse) on DU145 xenografts in nude and severe combined immunodeficient (SCID) mice were evaluated. GR expression in human prostate cancers was assessed by immunohistochemistry. All statistical tests were two-sided. RESULTS: Dexamethasone dose dependently decreased GR levels and inhibited the growth of DU145 and PC-3 but not LNCaP cells (DU145 cells, P< .001; PC-3 cells, P = .009). Dexamethasone increased IkappaBalpha protein levels and the cytosolic accumulation of NF-kappaB in DU145 cells and decreased secreted IL-6 levels to 37 pg/mL (95% confidence interval [CI] = 33 pg/mL to 41 pg/mL), compared with 164 pg/mL (95% CI = 162 pg/mL to 166 pg/mL) secreted by ethanol-treated control cells. Dexamethasone inhibited the growth of DU145 xenografts in nude (P = .006) and SCID (P = .026) mice without affecting GR levels. Eight of 16 human prostate cancers expressed GR at high levels (>or=30% GR-positive cells). CONCLUSION: Dexamethasone inhibited the growth of GR-positive cancers, possibly through the disruption of the NF-kappaB-IL-6 pathway.


Asunto(s)
Andrógenos/fisiología , Dexametasona/farmacología , Proteínas I-kappa B , Neoplasias de la Próstata/patología , Animales , Western Blotting , División Celular/efectos de los fármacos , Proteínas de Unión al ADN/metabolismo , Humanos , Interleucina-6/metabolismo , Masculino , Ratones , Ratones Desnudos , Modelos Animales , Inhibidor NF-kappaB alfa , FN-kappa B/metabolismo , Trasplante de Neoplasias , Neoplasias de la Próstata/metabolismo , Receptores de Glucocorticoides/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transfección , Trasplante Heterólogo/patología , Células Tumorales Cultivadas
8.
Cancer Res ; 61(4): 1382-5, 2001 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-11245438

RESUMEN

Fas (Apo-1/CD95) is a cell-surface receptor involved in cell death signaling through binding of Fas ligand. Mutation of the Fas gene results in accumulation of lymphoid cells and thus might contribute to lymphomagenesis. Thyroid lymphoma (TL) is supposed to arise from active lymphoid cells formed in the preceding autoimmune chronic lymphocytic thyroiditis (CLTH). We examined the open reading frame of Fas cDNA in 11 cases of CLTH and 26 cases of TL. These patients were admitted to the hospital with varying degrees of goiter. All of the CLTH patients were female, with median age of 65 years, and all but five cases of TL were female, with median age of 61 years. Mutations of the Fas gene were detected in 3 (27.3%) of 11 cases of CLTH and 17 (65.4%) of 26 of TL. The Fas mutations comprised 18 frameshift, 3 missense, and 1 nonsense mutation. Frameshift mutations were caused by insertion of 1 bp (A) at nucleotide 1095 in 10 cases and by lack of exon 8 in 8 cases. The insertion of 1 bp (A) at nucleotide 1095 has never been reported in other kinds of malignancies. Thus, this might be unique in TL and CLTH and might be mutational hotspots in these diseases. All mutations occurred in the cytoplasmic region (death domain) known to be involved in the apoptotic signal transduction and thus could be loss-of-function mutations. These findings suggested that accumulation of lymphoid cells in CLTH with Fas mutation provides a basis for development of TL.


Asunto(s)
Mutación del Sistema de Lectura , Linfoma no Hodgkin/genética , Mutación Puntual , Neoplasias de la Tiroides/genética , Receptor fas/genética , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Inmunohistoquímica , Linfoma no Hodgkin/inmunología , Masculino , Persona de Mediana Edad , Neoplasias de la Tiroides/inmunología , Receptor fas/biosíntesis
9.
Cancer Res ; 53(18): 4329-36, 1993 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-8364928

RESUMEN

Transforming growth factor alpha (TGF-alpha) has been shown to induce liver tumors within 1 year in transgenic male mice in which this potent mitogen is overexpressed. To determine more precisely how TGF-alpha participates in multistep tumorigenesis of the liver, genotoxic (diethylnitrosamine or dimethylnitrosamine) and nongenotoxic (phenobarbital) chemical carcinogens were administered independently to TGF-alpha transgenic mice [line MT42 on a Crl:CD-1(ICR)BR background]. TGF-alpha overexpression dramatically accelerated carcinogen-induced hepatocarcinogenesis in MT42 males but not females. Interestingly, all three chemical agents were found to enhance strongly both hepatic tumor formation and progression in TGF-alpha transgenic male mice. In this study 100%, 90%, and 78% of transgenic males exposed to diethylnitrosamine, dimethylnitrosamine or phenobarbital, respectively, developed tumors between 24 and 32 weeks of age. Moreover, approximately 70% of tumor-bearing transgenic mice from each treatment group had hepatocellular carcinomas; no malignant lesions were found in any carcinogen-treated or untreated nontransgenic mice or in untreated MT42 mice at this age. These results demonstrate that chemical agents as diverse as nitrosamines and phenobarbital act as cocarcinogens with TGF-alpha in the livers of these transgenic mice, indicating that TGF-alpha possesses the unique ability to complement both initiation and promotion in hepatocarcinogenesis. Furthermore, because carcinogen-induced malignant conversion was restricted to transgenic mice, constitutive TGF-alpha overexpression may promote liver tumor progression as well.


Asunto(s)
Neoplasias Hepáticas Experimentales/inducido químicamente , Factor de Crecimiento Transformador alfa/fisiología , Animales , Dietilnitrosamina/toxicidad , Dimetilnitrosamina/toxicidad , Receptores ErbB/análisis , Femenino , Masculino , Ratones , Ratones Transgénicos , Factor de Crecimiento Transformador alfa/análisis , Factor de Crecimiento Transformador alfa/genética
10.
Cancer Res ; 58(22): 5157-67, 1998 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-9823327

RESUMEN

The molecular and genetic events that contribute to the genesis and progression of cutaneous malignant melanoma, a complex and aggressive disease with a high propensity for metastasis, are poorly understood due in large part to the dearth of relevant experimental animal models. Here we used transgenic mice ectopically expressing hepatocyte growth factor/scatter factor (HGF/SF) to show that the Met signaling pathway is an important in vivo regulator of melanocyte function, whose subversion induces malignant melanoma. Tumorigenesis occurred in stages, beginning with the abnormal accumulation of melanocytes in the epidermis and dermis and culminating in the development of metastatic melanoma. Oncogenesis in this model was driven by creation of HGF/SF-Met autocrine loops through forced expression of the transgenic ligand and apparent selection of melanocytes overexpressing endogenous receptor, rather than paracrine stimulation or mutational activation of c-met. Preference for liver as a metastatic target correlated with high HGF/SF-Met autocrine activity, consistent with the notion that such activity may influence colonization. Although basic fibroblast growth factor and its receptor were both weakly expressed in the majority of melanomas examined, high levels were found only in those rare neoplasms with low or undetectable HGF/SF and Met expression, suggesting that these two tyrosine kinase receptor autocrine loops serve a critical overlapping function in melanocytic tumorigenesis. Our data support a causal role for HGF/SF-Met signaling in the development of melanoma and acquisition of the metastatic phenotype. Moreover, this transgenic mouse should serve as a highly useful model, facilitating our understanding of mechanisms by which human melanoma progresses to malignancy and expediting the development of efficacious therapeutic modalities designed to constrain metastasis.


Asunto(s)
Factor de Crecimiento de Hepatocito/metabolismo , Melanocitos/metabolismo , Melanoma Amelanótico/etiología , Melanoma Amelanótico/secundario , Proteínas de Neoplasias/metabolismo , Transducción de Señal , Neoplasias Cutáneas/etiología , Neoplasias Cutáneas/patología , Animales , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Transgénicos , Proteínas Proto-Oncogénicas c-met/metabolismo
11.
Oncogene ; 8(7): 1825-32, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8099726

RESUMEN

Deletion mapping of chromosome 3p was performed on 47 cases of human uterine cervical cancer using 24 polymorphic DNA markers including five inter-Alu DNA markers and two NotI-boundary cosmid markers obtained in our laboratory. The most likely order of these 24 polymorphic DNA markers was determined as being cen-[D3S4, H8]-D3S693-D3S659-D3S30-D3S687-[D3S2, UR9, UR47]-J36-J17-GNAI2B-D3F15S2-D3S643- D3S32-D3S23-D3S686-H35-UR189-D3S685-D3S 11 - D3S12-THRB-D3S22-pter, based on the data from radiation hybrid mapping genetic linkage analysis and in situ hybridization. Loss of heterozygosity (LOH) at one or more loci on chromosome 3p was detected in 21 of 47 cases (45%). Four tumors showed partial or interstitial deletions, and the common region of LOH in these tumors was 3p13-p21.1 between the D3S30 marker and the D3S2 marker. Candidates for tumor-suppressor genes, APEH, D8, GNA12B, ZNF35, RARB, THRB and RAFI, were all mapped outside of the common region in uterine cervical cancer. However, this region is commonly deleted in carcinoma of the lung, breast and kidney, and encompasses the breakpoint of the (3;8) translocation in hereditary renal cell carcinoma. This result indicates the presence of a novel tumor-suppressor gene in the region of 3p13-p21.1, which is involved in the development of several human cancers.


Asunto(s)
Deleción Cromosómica , Mapeo Cromosómico , Cromosomas Humanos Par 3 , Neoplasias del Cuello Uterino/genética , Secuencia de Bases , Femenino , Genes Supresores de Tumor , Marcadores Genéticos , Humanos , Datos de Secuencia Molecular , Polimorfismo de Longitud del Fragmento de Restricción
12.
Oncogene ; 7(6): 1185-9, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1594247

RESUMEN

It has been suggested that loss of heterozygosity (LOH) on the short arm of chromosome 1 is a critical event for the development of neuroblastoma, and we have previously shown frequent LOH on chromosome 14 in neuroblastoma. To pursue these observations, especially to define further the regions which are commonly deleted in the tumor, we examined for allelic losses in 27 cases of neuroblastomas by using a number of polymorphic DNA markers for chromosomes 14q and 1p. LOH was observed in 10 out of the 25 informative cases (40%) on chromosome 14q and in eight out of the 21 informative cases (38%) on 1p. The commonly deleted regions were distal to the D14S13 locus (14q32-qter) on chromosome 14 and distal to the D1S112 locus (1p36.1-pter) on chromosome 1. These results strongly suggest that tumor-suppressor genes important in the pathogenesis of human neuroblastoma are located on the distal part of both chromosomes 14q and 1p.


Asunto(s)
Neoplasias Encefálicas/genética , Deleción Cromosómica , Cromosomas Humanos Par 14 , Cromosomas Humanos Par 1 , Neuroblastoma/genética , Alelos , Southern Blotting , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/terapia , Niño , Preescolar , Mapeo Cromosómico , Sondas de ADN , ADN de Neoplasias/genética , ADN de Neoplasias/aislamiento & purificación , Genotipo , Heterocigoto , Humanos , Lactante , Estadificación de Neoplasias , Neuroblastoma/patología , Neuroblastoma/terapia
13.
Biochim Biophys Acta ; 922(3): 314-22, 1987 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-2825796

RESUMEN

We have examined the preferential incorporation of specific fatty acids into phospholipid classes of cultured human umbilical vein endothelial cells. Pulse-labeling of human umbilical vein endothelial cell phospholipids with radiolabeled fatty acids and inhibition of radiolabeled fatty acid incorporation by competition with excess, unlabeled fatty acids in pair-wise combinations revealed two distinct classes of esterification systems into human umbilical vein endothelial cell phospholipids. The eicosanoid precursor fatty acids, including arachidonate, 8,11,14-eicosatrienoate (ETA) and 5,8,11,14,17-eicosapentaenoate (EPA), exhibited high affinity incorporation into total phospholipids, whereas other fatty acids, including docosahexaenoate and monohydroxy eicosatetraenoates, showed low affinity incorporation. The relative degree of incorporation of eicosanoid precursor fatty acids into phospholipid classes was phosphatidylcholine (PC) greater than phosphatidylethanolamine (PE) greater than phosphatidylinositol (PI) greater than phosphatidylserine (PS). The specific activity of [14C]arachidonic acid-labeled PI was two times higher than that of any other radiolabeled phospholipids. When competitive incorporation of eicosanoid precursor fatty acids into phospholipid classes was studied, they were found to be acylated into different phospholipid classes at different rates. Although eicosanoid precursor fatty acids were not preferentially incorporated into PC, arachidonic acid was preferentially incorporated into the other phospholipids and exhibited particular selectivity in comparison with the other eicosanoid precursor fatty acids for incorporation into PI. These results demonstrate that human umbilical vein endothelial cells possess selective incorporation mechanisms for specific fatty acids into various phospholipids via the deacylation-reacylation pathway.


Asunto(s)
Ácidos Eicosanoicos/metabolismo , Endotelio Vascular/metabolismo , Ácidos Grasos/metabolismo , Fosfolípidos/metabolismo , Ácido 8,11,14-Eicosatrienoico/metabolismo , Ácidos Docosahexaenoicos/metabolismo , Ácido Eicosapentaenoico/metabolismo , Humanos , Ácidos Hidroxieicosatetraenoicos/metabolismo , Venas Umbilicales/metabolismo
14.
Biochim Biophys Acta ; 799(2): 151-7, 1984 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-6203553

RESUMEN

Rabbit antibody highly specific for guinea-pig liver NADPH-cytochrome c (P-450) reductase was found to inhibit dose-dependently the O2- -generating activity of the membrane fraction isolated from phorbol-myristate acetate-stimulated, homologous polymorphonuclear leukocytes. In addition, the antibody also could inhibit the NADPH-cytochrome c (Nitroblue tetrazolium) reductase separated from the membrane fractions and phagosomes of leukocytes by polyacrylamide gel electrophoresis or gel filtration on a Sephacryl S-300 column in the presence of 0.2% Triton X-100. These results demonstrate that the NADPH-cytochrome c reductase in the membrane fractions of leukocytes is antigenically cross-reactive with homologous liver NADPH-cytochrome c reductase, and also suggest that the enzyme of leukocytes participates in the respiratory burst.


Asunto(s)
Anticuerpos , Hígado/enzimología , NADH NADPH Oxidorreductasas/metabolismo , NADPH-Ferrihemoproteína Reductasa/fisiología , Neutrófilos/enzimología , Superóxidos/metabolismo , Animales , Anticuerpos/inmunología , Membrana Celular/enzimología , Epítopos/inmunología , Cobayas , NADPH Oxidasas , NADPH-Ferrihemoproteína Reductasa/antagonistas & inhibidores , NADPH-Ferrihemoproteína Reductasa/inmunología , Conejos/inmunología
15.
Biochim Biophys Acta ; 732(3): 569-78, 1983 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-6307374

RESUMEN

Electrophoretic isolation of a membrane-bound NADPH oxidase of guinea-pig polymorphonuclear leukocytes was attempted with the O2- -generating membranes of cells unstimulated or stimulated with C3b-zymosan or sodium dodecyl sulfate, and also with the phagosomes isolated from the phorbol myristate acetate-coated latex particle-phagocytosing cells. When these vesicles were subjected to discontinuous polyacrylamide gel electrophoresis in the presence of Triton X-100 and then assayed for NADPH-Nitroblue tetrazolium reducing activity, the activity was detected by the appearance of a single, blue band of the reduced dye on the gel, independent of the source of vesicles. In addition, the enzyme was able to generate O2- and its activity was significantly augmented with the homologous liver microsomal cytochrome b5. Its activity was heat-labile and inactivated by N-ethylmaleimide and p-chloromercuribenzene sulfonate. The enzyme, with an apparent molecular weight of 150 000, in the phagosomes was easily susceptible to limited proteolysis by trypsin and formed an active fragment with a molecular weight of 70 000, accompanying the loss of O2- -generating activity of the vesicles.


Asunto(s)
NADH NADPH Oxidorreductasas/sangre , Neutrófilos/enzimología , Animales , Fraccionamiento Celular , Membrana Celular/enzimología , Membrana Celular/ultraestructura , Complemento C3b/farmacología , Cobayas , NADH NADPH Oxidorreductasas/aislamiento & purificación , NADPH Oxidasas , Fagocitosis , Dodecil Sulfato de Sodio/farmacología , Superóxidos/sangre , Zimosan/farmacología
16.
Biochim Biophys Acta ; 1213(3): 302-8, 1994 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-8049243

RESUMEN

Biological activities of two epimeric 24-fluorinated vitamin D-2 analogs, 24-fluoro-1 alpha,25-dihydroxyvitamin D-2 [24-F-1,25-(OH)2D2] and its 24-epimer [24-epi-24-F-1,25-(OH)2D2], were studied and compared with 1 alpha,25-dihydroxyvitamin D-3 [1,25-(OH)2D3] and 1 alpha,25-dihydroxyvitamin D-2 [1,25-(OH)2D2]. 24-F-1,25-(OH)2D2 was nearly as active as 1,25-(OH)2D3 and 1,25-(OH)2D2 both in regulating calcium metabolism in vivo including bone mineral mobilization and intestinal calcium transport and in inducing differentiation of HL-60 cells. While 24-epi-24-F-1,25-(OH)2D2 showed distinct properties in these two types of the actions. Though the 24-epimer was nearly as potent as 1,25-(OH)2D3 in inducing differentiation of HL-60 cells, it showed little activity in regulating calcium metabolism in vivo. The fluorine atom introduced at the 24-position of either 1,25-(OH)2D2 or its 24-epimer had no potentiating effect. This is in sharp contrast with the cases of 24- and 26,27-multifluorinated analogs of active vitamin D-3.


Asunto(s)
Ergocalciferoles/síntesis química , Animales , Transporte Biológico , Resorción Ósea , Calcio/sangre , Calcio/metabolismo , Diferenciación Celular/efectos de los fármacos , Ergocalciferoles/metabolismo , Humanos , Ratas , Ratas Sprague-Dawley , Estereoisomerismo , Células Tumorales Cultivadas
17.
Chem Biol ; 8(11): 1011-24, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11731293

RESUMEN

BACKGROUND: The secosteroid 1 alpha,25-dihydroxyvitamin D(3) (1) has a wide variety of biological activities, which makes it a promising therapeutic agent for the treatment of cancer, psoriasis and osteoporosis. Insight into the structure-activity relationships of the A-ring of 1 is still needed to assist the development of more potent and selective analogues as candidate chemotherapeutic agents, as well as to define the molecular mode of action. RESULTS: All possible A-ring stereoisomers of 5,6-trans-2-methyl-1,25-dihydroxyvitamin D(3) (6a-h) and their 20-epimers (7a-h) were designed and efficiently synthesized. The dependence of the affinities for vitamin D receptor (VDR) and vitamin D binding protein (DBP), as well as the HL-60 cell differentiation-inducing activity, upon the stereochemistry of the A-ring and at C20 in the side chain was evaluated. CONCLUSIONS: The binding affinities and potency of the 5,6-trans and 5,6-cis analogues were enhanced by a 2-methyl substituent in a certain orientation. Molecular docking studies based upon the X-ray crystal structure of VDR suggested that the axial 2-methyl group would be accommodated in a pocket surrounded by hydrophobic amino acid residues in the ligand binding domain, resulting in enhanced interaction.


Asunto(s)
Vitamina D/análogos & derivados , Vitamina D/química , Animales , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacología , Sitios de Unión , Bovinos , Diferenciación Celular/efectos de los fármacos , Células HL-60 , Humanos , Unión Proteica , Conformación Proteica , Receptores de Calcitriol/química , Receptores de Calcitriol/metabolismo , Estereoisomerismo , Relación Estructura-Actividad , Timo , Vitamina D/metabolismo , Vitamina D/farmacología , Proteína de Unión a Vitamina D/química , Proteína de Unión a Vitamina D/metabolismo
18.
Transplant Proc ; 47(10): 2944-51, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26707319

RESUMEN

INTRODUCTION: To address the shortage of donor hearts for transplantation, there is significant interest in liberalizing donor acceptance criteria. Therefore, the aim of this study was to evaluate cardiac donor characteristics from the United Network for Organ Sharing (UNOS) database to determine their impact on posttransplantation recipient outcomes. METHODS: Adult (≥18 years) patients undergoing heart transplantation from July 1, 2004, to December 31, 2012, in the UNOS Standard Transplant Analysis and Research (STAR) database were reviewed. Patients were stratified by 1-year posttransplantation status; survivors (group S, n = 13,643) and patients who died or underwent cardiac retransplantation at 1-year follow-up (group NS/R = 1785). Thirty-three specific donor variables were collected for each recipient, and independent donor predictors of recipient death or retransplantation at 1 year were determined using multivariable logistic regression analysis. RESULTS: Overall 1-year survival for the entire cohort was 88.4%. Mean donor age was 31.5 ± 11.9 years, and 72% were male. On multivariable logistic regression analysis, donor age >40 years (odds ratio [OR] 1.44, 95% confidence interval [CI] 1.27 to 1.64), graft ischemic time >3 hours (OR 1.32, 1.16 to 1.51), and the use of cardioplegia (OR 1.17, 1.01 to 1.35) or Celsior (OR 1.21, 1.06 to 1.38) preservative solution were significant predictors of recipient death or retransplantation at 1 year posttransplantation. Male donor sex (OR 0.83, 0.74 to 0.93) and the use of antihypertensive agents (OR 0.88, 0.77 to 1.00) or insulin (OR 0.84, 0.76 to 0.94) were protective from adverse outcomes at 1 year. CONCLUSIONS: These data suggest that donors who are older, female, or have a long projected ischemic time pose greater risk to heart transplant recipients in the short term. Additionally, certain components of donor management protocols, including antihypertensive and insulin administration, may be protective to recipients.


Asunto(s)
Supervivencia de Injerto , Trasplante de Corazón/mortalidad , Donantes de Tejidos/estadística & datos numéricos , Adulto , Factores de Edad , Antihipertensivos/uso terapéutico , Isquemia Fría/mortalidad , Bases de Datos Factuales , Femenino , Humanos , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Reoperación/estadística & datos numéricos , Factores de Riesgo , Factores Sexuales , Sobrevivientes/estadística & datos numéricos , Factores de Tiempo
19.
Endocrinology ; 108(6): 2067-71, 1981 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6894423

RESUMEN

To investigate the biological importance of 24R-hydroxylation of 25-hydroxyvitamin D to the early development of rats, the potency of 24,24-difluoro-25-hydroxyvitamin D3 had been compared to that of 25-hydroxyvitamin D3 in young rat pups born to vitamin D-deficient mothers. 24,24-Difluoro-25-hydroxyvitamin D3 and 25-hydroxyvitamin D3 were equally active in stimulating active calcium transport in the intestine, maintaining normal concentrations of calcium and phosphorus in the plasma and promoting bone growth and mineralization. These results provide strong evidence that the presence of a hydroxyl group at the 24 position of vitamin D3 is not required for the maintenance of calcium-phosphate homeostasis during growth and in the development and mineralization of bone.


Asunto(s)
Animales Recién Nacidos/crecimiento & desarrollo , Desarrollo Óseo/efectos de los fármacos , Hidroxicolecalciferoles/farmacología , Deficiencia de Vitamina D/metabolismo , Animales , Transporte Biológico Activo/efectos de los fármacos , Calcifediol , Calcio/sangre , Calcio/metabolismo , Femenino , Hidroxilación , Mucosa Intestinal/metabolismo , Masculino , Fósforo/sangre , Embarazo , Ratas , Relación Estructura-Actividad
20.
Stroke ; 32(10): 2237-45, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11588307

RESUMEN

BACKGROUND AND PURPOSE: We investigated serial metabolic changes in frontal lobes of patients with deep intracerebral hemorrhage (ICH) to examine the correlation between N-acetylaspartate (NAA) and degree of motor impairment or clinical outcome. METHODS: - Twenty patients with deep ICH were examined with proton magnetic resonance spectroscopy with the application of a multivoxel method (1 voxel=10x10x20 mm; 64 voxels). NAA/creatine ratios in the white matter of the primary motor and premotor areas on both sides were measured sequentially: within 48 hours, at 2 weeks, and 1 month after onset. The National Institutes of Health Stroke Scale and Barthel Index for disability were measured for each patient. RESULTS: - In the primary motor area on the affected side, where the hematoma did not extend, the NAA/creatine ratio decreased sequentially. At 48 hours and 2 weeks after onset, a negative correlation was detected between NAA/creatine and hematoma volume, but there was no correlation 1 month later. At 2 weeks, NAA/creatine correlated negatively with motor impairment (r=-0.750), and there was a significant correlation with clinical outcome as early as 2 weeks after onset (r=0.954). These sequential changes of NAA/creatine varied according to patients' long-term clinical outcome. Patients with poor outcome demonstrated notable reduction of NAA/creatine over the bilateral frontal lobes. CONCLUSIONS: - The delayed gradual reduction of NAA/creatine ratio in the frontal lobes correlates with motor deficit and clinical outcome after deep ICH, suggesting that the neural networks in the frontal lobe could be important for recovery.


Asunto(s)
Hemorragia de los Ganglios Basales/diagnóstico , Hemorragia de los Ganglios Basales/metabolismo , Lóbulo Frontal/metabolismo , Espectroscopía de Resonancia Magnética , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/metabolismo , Anciano , Anciano de 80 o más Años , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Hemorragia de los Ganglios Basales/complicaciones , Hemorragia de los Ganglios Basales/terapia , Creatina/metabolismo , Progresión de la Enfermedad , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/terapia , Resultado del Tratamiento
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