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1.
Malays J Pathol ; 42(1): 115-119, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32342940

RESUMEN

INTRODUCTION: Alveolar rhabdomyosarcoma (RMS) usually occurs in adolescents and young adults, and most frequently arises in the extremities. CASE REPORT: We present a rare case of metastatic alveolar RMS from a nasal primary to cervical lymph nodes (LNs) in an elderly patient, diagnosed on the fine-needle aspiration (FNA) biopsy. Smears showed malignant round cells featuring focal rhabdoid appearance, with rhabdomyoblastic differentiation further supported by immunocytochemical stains. Diagnosis of alveolar RMS was confirmed by fluorescence in situ hybridization (FISH) identifying FOXO1 gene involvement with dual colour break-apart probes at locus 13q14. DISCUSSION: The differential diagnosis for a small round blue cell tumour in the elderly generally includes metastatic small cell carcinoma, lymphoma, malignant melanoma, RMS, desmoplastic small round cell tumour and Ewing's sarcoma/primitive neuroectodermal tumour. Subtle morphological analysis and expression pattern of immunostaining for skeletal muscle differentiation led to the diagnosis of RMS. Cytogenetic testing on the FOXO1 gene rearrangement helps definite subtyping of alveolar RMS.


Asunto(s)
Metástasis Linfática/patología , Cavidad Nasal/patología , Neoplasias Nasales/diagnóstico , Rabdomiosarcoma Alveolar/diagnóstico , Anciano , Biomarcadores de Tumor/análisis , Biopsia con Aguja Fina , Citodiagnóstico , Femenino , Humanos , Hibridación Fluorescente in Situ , Ganglios Linfáticos/patología , Neoplasias Nasales/patología , Rabdomiosarcoma Alveolar/patología
2.
Malays J Pathol ; 39(2): 171-174, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28866700

RESUMEN

Papillary thyroid carcinoma (PTC) is the most common thyroid carcinoma and is derived from thyroid follicular cells. In contrast, medullary thyroid carcinoma (MTC) is rare and originates from the parafollicular C-cells. Synchronous occurrence of these two carcinomas is uncommon and occurs as either discrete lesions or as a mixed lesion. The current case report describes a 50-year-old woman with synchronous multiple discrete MTC and PTC with lymph nodes metastasis. Pathologists and treating physicians should be aware of the synchronous coexistence of these entities to avoid possible misdiagnosis.


Asunto(s)
Carcinoma Neuroendocrino/patología , Carcinoma Papilar/patología , Neoplasias Primarias Múltiples/patología , Neoplasias de la Tiroides/patología , Femenino , Humanos , Metástasis Linfática/patología , Persona de Mediana Edad , Cáncer Papilar Tiroideo
3.
Lett Appl Microbiol ; 63(4): 240-6, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27432517

RESUMEN

UNLABELLED: Francisella tularensis is distributed in the Northern hemisphere and it is the bacterial agent responsible for tularaemia, a zoonotic disease. We collected 4 527 samples of DNA from ticks in Japan, which were then analysed by real-time PCR and nested PCR. Francisella DNA was detected by real-time PCR in 2·15% (45/2 093) of Ixodes ovatus, 0·66% (14/2 107) of I. persulcatus, 8·22% (6/73) of I. monospinosus and 0·72% (1/138) of Haemaphysalis flava specimens. Finally, Francisella DNA was detected by nested PCR in 42 and five samples I. ovatus and I. persulcatus, respectively, which were positive according to real-time PCR. Phylogenetic analysis showed that the sequence from I. ovatus and I. persulcatus were clustered with F. tularensis type B strains distributed in Eurasia. Microinjected live F. tularensis persisted in ticks, whereas heat-killed F. tularensis decreased. Microinjected F. tularensis hlyD mutant decreased in ticks significantly compared to parent strain, thereby suggesting that HlyD in F. tularensis contributes to the adaptation or survive of bacterial infection in ticks. SIGNIFICANCE AND IMPACTS OF THE STUDY: Francisella tularensis has been detected in ticks, suggesting that it is a tick-borne pathogen. However, F. tularensis has not been detected in ticks in Japan since 1991. In this study, we performed a large-scale analysis of DNA isolated from ticks in Japan and detected F. tularensis by real-time polymerase chain reaction (PCR) and nested PCR. We found that F. tularensis could survive in ticks based on an experimental tick-infection model. We also identified a bacterial factor that contributes to survival in ticks. Our results suggest that ticks are candidate vectors that mediate F. tularensis infection in Japan.


Asunto(s)
ADN Bacteriano/aislamiento & purificación , Francisella tularensis/crecimiento & desarrollo , Francisella tularensis/genética , Ixodes/microbiología , Animales , ADN Bacteriano/genética , Francisella tularensis/aislamiento & purificación , Proteínas Hemolisinas/genética , Japón , Filogenia , Reacción en Cadena en Tiempo Real de la Polimerasa , Tularemia/microbiología
4.
Perfusion ; 30(8): 653-9, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25721457

RESUMEN

BACKGROUND: We designed a non-invasive, observational, real-time study, using near-infrared spectroscopy (NIRS) to assess the in vivo effects of cardiopulmonary bypass (CPB) on patients' skeletal muscle as well as the effects of hemodilution and hypothermia on tissue oxygen delivery during CPB. METHODS: The study included 20 consecutive adult patients undergoing open-heart surgery with CPB. Evaluation parameters for peripheral circulation were measured using the NIRO-200NX and recorded every 30 seconds. To assess how hemodilution influences peripheral circulation parameters, we compared data between a group of patients with hematocrit (Hct) values >22% (high Hct group) and those with Hct values ⩽22% (low Hct group). RESULTS: Changes in the concentration of oxygenated hemoglobin (ΔO2Hb, µmol/L), which flows into the skeletal muscle, was an important factor for deciding the tissue oxygenation index (TOI%), showing the tissue oxygen saturation. The low Hct group showed a significant increase in the normalized tissue hemoglobin index (nTHI), showing the percentage change in the amount of initial hemoglobin and TOI compared to the high Hct group. Changes in the concentration of oxygenated hemoglobin (ΔO2Hb, µmol/L) and deoxygenated hemoglobin (ΔHHb, µmol/L) were significantly less in the low Hct group than in the high Hct group, thus, showing good peripheral circulation despite the low hematocrit levels. CONCLUSION: Our study indicated the presence of a compensatory mechanism in which increased blood flow of the microcirculation is in compensation for the lack of oxyhemoglobin delivery caused by hemodilution.


Asunto(s)
Puente Cardiopulmonar/métodos , Hemodilución/métodos , Microcirculación/fisiología , Músculo Esquelético/metabolismo , Adulto , Anciano , Hematócrito , Hemoglobinas/análisis , Humanos , Persona de Mediana Edad , Músculo Esquelético/irrigación sanguínea , Consumo de Oxígeno , Espectroscopía Infrarroja Corta
5.
Insect Mol Biol ; 23(4): 466-74, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24698498

RESUMEN

Salp16, a 16-kDa tick salivary gland protein, is known to be the molecule involved in the transmission of Anaplasma phagocytophilum, an obligate intracellular pathogen causing zoonotic anaplasmosis, from its mammalian hosts to Ixodes scapularis. Recently, the presence of A. phagocytophilum was documented in Japan and Ixodes persulcatus was identified as one of its vectors. The purpose of this study was to identify Salp16 genes in I. persulcatus and characterize their function. Two cDNA clones encoding the Salp16-like sequences were obtained from the salivary glands of fed female I. persulcatus ticks and designated Salp16 Iper1 and Iper2. Gene expression analyses showed that the Salp16 Iper genes were expressed specifically in the salivary glands and were up-regulated by blood feeding. These proteins attenuated the oxidative burst of activated bovine neutrophils and inhibited their migration induced by the chemoattractant interleukin-8 (IL-8). These results demonstrate that Salp16 Iper proteins contribute to the establishment of blood feeding as an immunosuppressant of neutrophil, an essential factor in innate host immunity. Further examination of the role of Salp16 Iper in the transmission of pathogens, including A. phagocytophilum, will increase our understanding of the tick-host-pathogen interface.


Asunto(s)
Anaplasma phagocytophilum/crecimiento & desarrollo , Anaplasmosis/transmisión , Ixodes/inmunología , Ixodes/microbiología , Neutrófilos/inmunología , Neutrófilos/microbiología , Glándulas Salivales/metabolismo , Proteínas y Péptidos Salivales/genética , Secuencia de Aminoácidos , Anaplasmosis/inmunología , Animales , Vectores Artrópodos , Secuencia de Bases , Bovinos/inmunología , ADN Complementario , Femenino , Datos de Secuencia Molecular , Glándulas Salivales/microbiología , Proteínas y Péptidos Salivales/metabolismo
6.
Insect Mol Biol ; 19(3): 359-65, 2010 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-20201978

RESUMEN

Salp15, a 15-kDa tick salivary gland protein, is known for several suppressive activities against host immunity and critical functions for the transmission of Lyme borrelia in Ixodes scapularis and Ixodes ricinus, the major vectors found in North America and Western Europe. Salp15 inhibits the activation of cluster of differentiation (CD)4(+)T-cells through the repression of T-cell receptor (TCR)-triggered calcium fluxes and interleukin (IL)-2 production. Furthermore, Salp15 adheres to the spirochaeta and specifically interacts with its outer surface protein C. The binding of Salp15 to Borrelia burgdorferi protects it from antibody-mediated killing in vitro. The aim of this study is to identify the Salp15 genes in Ixodes persulcatus Schulze, the specific vector for human Lyme borreliosis in Japan. Two cDNA clones encoding the Salp15-like sequence were obtained from salivary glands of fed female ticks. These genes encode 135- and 132-amino acid proteins, designated Salp15 Iper-1 and Salp15 Iper-2, respectively, both having signal peptide sequences and predicted to be secretory proteins. Salp15 Iper-1 and -2 showed 51.8 and 68.2% similarity to I. scapularis Salp15, respectively. Reverse transcriptase PCR analysis showed that Salp15 Iper genes were expressed specifically in the salivary glands throughout life cycle stages of the ticks and were up-regulated by blood feeding. In the I. persulcatus-derived sequences, the C-terminal part, which is the binding domain to the CD4 molecule of T-cells in I. scapularis Salp15, was well conserved. In the future, it will be necessary to analyse immunosuppressive functions of I. persulcatus Salp15 and their interaction with Borrelia spp. in Japan.


Asunto(s)
Genes de Insecto/genética , Inmunosupresores/metabolismo , Ixodes/genética , Ixodes/inmunología , Glándulas Salivales/metabolismo , Proteínas y Péptidos Salivales/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Femenino , Regulación de la Expresión Génica , Humanos , Datos de Secuencia Molecular , Filogenia , Proteínas y Péptidos Salivales/química , Proteínas y Péptidos Salivales/metabolismo , Homología de Secuencia de Aminoácido
7.
Anim Genet ; 39(4): 374-82, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18507651

RESUMEN

We examined the extent of linkage disequilibrium (LD) block lengths in four breed populations: Japanese Black, Angus, Hereford and Holstein. Three chromosomal regions in which QTL were previously mapped in Japanese Black populations were scanned with 84 microsatellite markers. The estimated LD lengths in these four purebred populations varied from 535 to 683 kb, which is much shorter than the values reported previously. Our findings suggest that QTL can be mapped in sub-centimorgan regions in these populations using an LD-mapping method. We also developed breed identification methods to distinguish Japanese Black from Angus, Hereford, Holstein and F(1) animals (Japanese Black x Holstein) respectively using the haplotypic frequencies of a pair of markers in the breed populations. After assessing the distributions of posterior probabilities to be Japanese Black, we obtained several pairs of markers that completely distinguished Japanese Black from the other breeds. We also obtained several combinations of six markers that completely distinguished Japanese Black animals from F(1) animals.


Asunto(s)
Bovinos/genética , Mapeo Cromosómico , Desequilibrio de Ligamiento , Algoritmos , Animales , Cruzamiento , Cromosomas de los Mamíferos/genética , Marcadores Genéticos , Variación Genética , Genética de Población , Haplotipos , Repeticiones de Microsatélite , Método de Montecarlo , Sitios de Carácter Cuantitativo , Sintenía
8.
Anim Biotechnol ; 19(3): 178-89, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18607790

RESUMEN

A disintegrin and metalloprotease (ADAM) 12 is a member of the ADAM family possessing a putative role in a variety of biological processes such as modulation of proteolytic processing, cell adhesion, cell fusion, and signaling. Recently, it has been suggested that ADAM12 is involved in regulation of adipogenesis as well as myogenesis. In this study, we have determined the genomic structure of 5'- and 3'-regions in the bovine ADAM12 gene. We could obtain characteristics of lower homology of its exon 2 with human counterpart. Human exon S19 encodes for the sequence specific to a shorter secreted form of ADAM12S. The bovine ADAM12 gene had no canonical 3'-splice acceptor site at 5'-side of the putative exon S19, suggesting that the cattle could not produce a ADAM12S counterpart. To identify the regulatory elements, a 12 kb 5'-flanking region of the gene was cloned and luciferase reporter assay was carried out. Reporter plasmids with different length of proximal promoter region indicated the similar patterns of promoter activities between 3T3-L1 preadipose and Cos-1 nonadipose cells. However, 2.0 and 0.2 kb fragments located at - 8 and - 4.5 kb upstream of the putative transcription start site, respectively, increased the ADAM12 promoter activity about 1.5- to 2-fold in 3T3-L1, but not in Cos-1. These results suggested that the two distal regions might contribute to the preadipocyte-specific expression of ADAM12 gene.


Asunto(s)
Proteínas ADAM/genética , Bovinos/genética , Proteínas de la Membrana/genética , Regiones Promotoras Genéticas , Homología de Secuencia de Ácido Nucleico , Región de Flanqueo 3' , Región de Flanqueo 5' , Proteína ADAM12 , Animales , Secuencia de Bases , Paseo de Cromosoma , Cromosomas Artificiales Bacterianos , Cromosomas de los Mamíferos/genética , Cartilla de ADN , Exones , Femenino , Humanos , Datos de Secuencia Molecular , Biblioteca de Péptidos , Plásmidos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Alineación de Secuencia , Análisis de Secuencia de ADN
9.
Int J Cosmet Sci ; 30(5): 353-60, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18822041

RESUMEN

South-East Asian population is daily exposed to strong sunlight. As a result, the majority of population will have darker, ethnic skin. Moreover, many people suffer from dark spots, hyperpigmentation, which is considered to be a skin disorder and causes psychological disturbance. To treat dark spots, most of the population will still rely on traditionally used crude drugs, knowledge about which is transferred from generation to generation. Fifty-two crude drugs were selected based on the survey performed among local healers and beauticians of different ethnic origin. These crude drugs were screened for mushroom tyrosinase inhibitory activity, as tyrosinase inhibitors are becoming increasingly important as cosmetic and medicinal products, primarily to control hyperpigmentation. Among the tested crude drugs, methanolic extracts of Glycyrrhiza glabra, Morus alba, Syzygium aromaticum, Citrus aurantifolia, Cypreae moneta, Punica granatum and Citrus aurantium, at the final concentration of 50 microg mL(-1), showed mushroom tyrosinase inhibitory activity of 78.9%, 71.0%, 69.4%, 59.0%, 56.0%, 53.4 and 51.9%, respectively, with 91.4% inhibitory activity of kojic acid taken as positive control. To our knowledge, this is the first report that extracts of Cypreae moneta shell and Syzygium aromaticum flowering bud have tyrosinase inhibitory activity. These potent extracts were further evaluated at different concentration. The final concentration of the extracts in reaction mixtures was 50, 25 and 5 microg mL(-1) for the initial concentration of 1000, 500 and 100 microg mL(-1), respectively. They showed concentration-dependent inhibition of mushroom tyrosinase. Those extracts expressing relatively weak tyrosinase inhibitory activity may act through different inhibition pathway which is not based on tyrosinase activity. Further evaluation of the most potent tyrosinase inhibitors in in vivo conditions would be recommended.


Asunto(s)
Inhibidores Enzimáticos/uso terapéutico , Monofenol Monooxigenasa/antagonistas & inhibidores , Preparaciones Farmacéuticas/análisis , Trastornos de la Pigmentación/tratamiento farmacológico , Inhibidores Enzimáticos/análisis , Humanos , Técnicas In Vitro , Nepal , Trastornos de la Pigmentación/enzimología , Extractos Vegetales/análisis , Extractos Vegetales/uso terapéutico , Especificidad de la Especie
10.
Int J Oral Maxillofac Surg ; 47(2): 199-204, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28823904

RESUMEN

This study re-examined the usefulness of surgery for the management of masticatory muscle tendon-aponeurosis hyperplasia (MMTAH) through a comparison of the outcomes between patients who underwent surgery and those who did not. The duration of follow-up was 2 years. Twenty-eight patients who attended the study hospital and were given a diagnosis of MMTAH were included. Nineteen patients underwent surgery (surgical group) and nine patients were instructed to open their mouths wide once a day and did not undergo surgery (non-surgical group). Maximum mouth opening, impairment of daily activities, satisfaction, and the status of mouth opening training were evaluated after surgery. The mean increase in mouth opening after 2 years was 20.2mm in the surgical group and 2.4mm in the non-surgical group. Adequate mouth opening training led to satisfactory results 2 years postoperative, and sustained mouth opening training for 6 months after surgery was a key factor for obtaining good outcomes. The general condition and personality of individual patients should be evaluated carefully before surgery to estimate whether or not they can endure the pain associated with postoperative mouth opening training. The results of this study suggest that the surgical procedure is useful for the management of MMTAH.


Asunto(s)
Aponeurosis , Músculos Masticadores/patología , Trastornos de la Articulación Temporomandibular/terapia , Adulto , Aponeurosis/diagnóstico por imagen , Niño , Contractura/diagnóstico por imagen , Contractura/cirugía , Femenino , Estudios de Seguimiento , Humanos , Hiperplasia/diagnóstico por imagen , Hiperplasia/terapia , Imagen por Resonancia Magnética , Masculino , Músculos Masticadores/diagnóstico por imagen , Persona de Mediana Edad , Procedimientos Quirúrgicos Orales , Radiografía Panorámica , Estudios Retrospectivos , Resultado del Tratamiento
11.
Mol Cell Biol ; 21(15): 5050-62, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11438661

RESUMEN

A pathway sensitive to rapamycin, a selective inhibitor of mammalian target of rapamycin (mTOR), down-regulates effects of insulin such as activation of Akt (protein kinase B) via proteasomal degradation of insulin receptor substrate 1 (IRS-1). We report here that the pathway also plays an important role in insulin-induced subcellular redistribution of IRS-1 from the low-density microsomes (LDM) to the cytosol. After prolonged insulin stimulation, inhibition of the redistribution of IRS-1 by rapamycin resulted in increased levels of IRS-1 and the associated phosphatidylinositol (PI) 3-kinase in both the LDM and cytosol, whereas the proteasome inhibitor lactacystin increased the levels only in the cytosol. Since rapamycin but not lactacystin enhances insulin-stimulated 2-deoxyglucose (2-DOG) uptake, IRS-1-associated PI 3-kinase localized at the LDM was suggested to be important in the regulation of glucose transport. The amino acid deprivation attenuated and the amino acid excess enhanced insulin-induced Ser/Thr phosphorylation and subcellular redistribution and degradation of IRS-1 in parallel with the effects on phosphorylation of p70 S6 kinase and 4E-BP1. Accordingly, the amino acid deprivation increased and the amino acid excess decreased insulin-stimulated activation of Akt and 2-DOG uptake. Furthermore, 2-DOG uptake was affected by amino acid availability even when the degradation of IRS-1 was inhibited by lactacystin. We propose that subcellular redistribution of IRS-1, regulated by the mTOR-dependent pathway, facilitates proteasomal degradation of IRS-1, thereby down-regulating Akt, and that the pathway also negatively regulates insulin-stimulated glucose transport, probably through the redistribution of IRS-1. This work identifies a novel function of mTOR that integrates nutritional signals and metabolic signals of insulin.


Asunto(s)
Acetilcisteína/análogos & derivados , Insulina/metabolismo , Fosfoproteínas/metabolismo , Proteínas Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas , Acetilcisteína/farmacología , Proteínas Adaptadoras Transductoras de Señales , Adenoviridae/genética , Aminoácidos/química , Animales , Transporte Biológico , Proteínas Portadoras/metabolismo , Proteínas de Ciclo Celular , Línea Celular , Cisteína Endopeptidasas/metabolismo , Citosol/metabolismo , Desoxiglucosa/farmacocinética , Regulación hacia Abajo , Inhibidores Enzimáticos/farmacología , Factores Eucarióticos de Iniciación , Glucosa/metabolismo , Humanos , Immunoblotting , Proteínas Sustrato del Receptor de Insulina , Ratones , Complejos Multienzimáticos/metabolismo , Fosforilación , Pruebas de Precipitina , Complejo de la Endopetidasa Proteasomal , Unión Proteica , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-akt , Proteínas Quinasas S6 Ribosómicas/metabolismo , Serina/química , Transducción de Señal , Sirolimus/farmacología , Fracciones Subcelulares/metabolismo , Serina-Treonina Quinasas TOR , Treonina/química , Factores de Tiempo , Tirosina/metabolismo
12.
Cancer Res ; 47(24 Pt 1): 6806-9, 1987 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-3499981

RESUMEN

Expression of the human placental form of glutathione S-transferase (GST-pi) in dysplasia (53 cases), carcinoma in situ (10 cases), and invasive carcinoma (46 cases) of human uterine cervix was investigated immunohistochemically with specific anti-GST-pi rabbit antibody. While normal squamous epithelium was largely negative, the binding of antibody was appreciable in mild and moderate dysplasias, especially in the cytoplasm of cells demonstrating koilocytotic atypia. In severe dysplasia, the nuclei as well as the cytoplasm were strongly stained in all cell layers except for the superficial layer, and in carcinoma in situ both of them were also strongly stained in all cell layers. In invasive carcinoma, over 90% of cases exhibited strong cytoplasmic staining and in over 70% the nuclei were positive. GST activity towards 1-chloro-2,4-dinitrobenzene and GST-pi protein content were significantly increased in all of 4 squamous cell carcinomas examined as compared to values for normal cervical epithelia. Two-dimensional gel electrophoresis followed by immunoblotting using the GST-pi antibody demonstrated that, of many cytoplasmic proteins, only the GST-pi subunit was specifically bound. These results indicate that GST-pi is a potentially useful immunohistochemical marker for (pre)neoplasia of human uterine cervix. In addition, it was demonstrated that the cells in severe dysplasia, carcinoma in situ, and invasive carcinoma expressing GST-pi were often characterized by staining with a monoclonal antibody to the v-H-ras gene product.


Asunto(s)
Glutatión Transferasa/análisis , Placenta/enzimología , Displasia del Cuello del Útero/enzimología , Neoplasias del Cuello Uterino/enzimología , Femenino , Humanos , Inmunohistoquímica , Proteína Oncogénica p21(ras) , Proteínas Oncogénicas Virales/análisis , Displasia del Cuello del Útero/patología , Neoplasias del Cuello Uterino/patología
13.
Diabetes ; 50(8): 1891-900, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11473053

RESUMEN

Growth hormone (GH) is well known to induce in vivo insulin resistance. However, the molecular mechanism of GH-induced cellular insulin resistance is largely unknown. In this study, we demonstrated that chronic GH treatment of differentiated 3T3-L1 adipocytes reduces insulin-stimulated 2-deoxyglucose (DOG) uptake and activation of Akt (also known as protein kinase B), both of which are downstream effects of phosphatidylinositol (PI) 3-kinase, despite enhanced tyrosine phosphorylation of insulin receptor substrate (IRS)-1, association of IRS-1 with the p85 subunit of PI 3-kinase, and IRS-1-associated PI 3-kinase activity. In contrast, chronic GH treatment did not affect 2-DOG uptake and Akt activation induced by overexpression of a membrane-targeted form of the p110 subunit of PI 3-kinase (p110(CAAX)) or Akt activation stimulated by platelet-derived growth factor. Fractionation studies indicated that chronic GH treatment reduces insulin-stimulated translocation of Akt from the cytosol to the plasma membrane. Interestingly, chronic GH treatment increased insulin-stimulated association of IRS-1 with p85 and IRS-1-associated PI 3-kinase activity preferentially in the cytosol. These results indicate that cellular insulin resistance induced by chronic GH treatment in 3T3-L1 adipocytes is caused by uncoupling between activation of PI 3-kinase and its downstream signals, which is specific to the insulin-stimulated PI 3-kinase pathway. This effect of GH might result from the altered subcellular distribution of IRS-1-associated PI 3-kinase.


Asunto(s)
Adipocitos/fisiología , Hormona de Crecimiento Humana/farmacología , Resistencia a la Insulina/fisiología , Insulina/farmacología , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal/fisiología , Células 3T3 , Adipocitos/citología , Adipocitos/efectos de los fármacos , Animales , Transporte Biológico/efectos de los fármacos , Línea Celular , Citosol/metabolismo , Desoxiglucosa/metabolismo , Humanos , Proteínas Sustrato del Receptor de Insulina , Factor I del Crecimiento Similar a la Insulina/farmacología , Janus Quinasa 2 , Cinética , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/fisiología , Ratones , Microsomas/metabolismo , Fosfoproteínas/metabolismo , Fosfotirosina/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-akt , Proteínas Recombinantes/metabolismo , Transducción de Señal/efectos de los fármacos , Porcinos , Transfección
14.
Diabetes ; 50(5): 1083-92, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11334412

RESUMEN

Tumor necrosis factor (TNF)-alpha is one of the candidate mediators of insulin resistance associated with obesity, a major risk factor for the development of type 2 diabetes. The insulin resistance induced by TNF-alpha is antagonized by thiazolidinediones (TZDs), a new class of insulin-sensitizing drugs. The aim of the current study was to dissect the mechanism whereby pioglitazone, one of the TZDs, ameliorates TNF-alpha-induced insulin resistance in 3T3-L1 adipocytes. Pioglitazone restored insulin-stimulated 2-deoxyglucose (DOG) uptake, which was reduced by TNF-alpha, with concomitant restorations in tyrosine phosphorylation and protein levels of insulin receptor (IR) and insulin receptor substrate (IRS)-1, as well as association of the p85 regulatory subunit of phosphatidylinositol (PI) 3-kinase with IRS-1 and PI 3-kinase activity. Adenovirus-mediated gene transfer of either wild-type human peroxisome proliferator-activated receptor (PPAR)-gamma2 or a mutant carrying a replacement at the consensus mitogen-activated protein kinase phosphorylation site (hPPAR-gamma2-S112A) promoted adipogenesis of 3T3-L1 fibroblasts and restored TNF-alpha-induced decrease of triglyceride in adipocytes as effectively as pioglitazone. Overexpression of the PPAR-gamma proteins in TNF-alpha-treated adipocytes restored protein levels of IR/IRS-1, but did not improve insulin-stimulated tyrosine phosphorylation of IR/IRS-1 or insulin-stimulated 2-DOG uptake. These results indicate that the ability of pioglitazone to restore insulin-stimulated tyrosine phosphorylation of IR/IRS-1, which is necessary for amelioration of TNF-alpha-induced insulin resistance, may be independent of the adipogenic activity of PPAR-gamma that regulates protein levels of IR/IRS-1.


Asunto(s)
Adipocitos/fisiología , Hipoglucemiantes/farmacología , Resistencia a la Insulina/fisiología , Receptores Citoplasmáticos y Nucleares/fisiología , Tiazoles/farmacología , Tiazolidinedionas , Factores de Transcripción/fisiología , Factor de Crecimiento Transformador alfa/farmacología , Células 3T3 , Adipocitos/citología , Adipocitos/efectos de los fármacos , Animales , Diferenciación Celular , Línea Celular , Desoxiglucosa/metabolismo , Humanos , Insulina/farmacología , Ratones , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación , Fosfotirosina/metabolismo , Pioglitazona , Receptores Citoplasmáticos y Nucleares/efectos de los fármacos , Proteínas Recombinantes/antagonistas & inhibidores , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacología , Factores de Transcripción/efectos de los fármacos , Transfección , Factor de Crecimiento Transformador alfa/antagonistas & inhibidores
15.
Mol Endocrinol ; 14(6): 783-94, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10847581

RESUMEN

Insulin receptor substrate-1 (IRS-1) is a major substrate of the insulin receptor and acts as a docking protein for Src homology 2 domain containing signaling molecules that mediate many of the pleiotropic actions of insulin. Insulin stimulation elicits serine/threonine phosphorylation of IRS-1, which produces a mobility shift on SDS-PAGE, followed by degradation of IRS-1 after prolonged stimulation. We investigated the molecular mechanisms and the functional consequences of these phenomena in 3T3-L1 adipocytes. PI 3-kinase inhibitors or rapamycin, but not the MEK inhibitor, blocked both the insulin-induced electrophoretic mobility shift and degradation of IRS-1. Adenovirus-mediated expression of a membrane-targeted form of the p110 subunit of phosphatidylinositol (PI) 3-kinase (p110CAAX) induced a mobility shift and degradation of IRS-1, both of which were inhibited by rapamycin. Lactacystin, a specific proteasome inhibitor, inhibited insulin-induced degradation of IRS-1 without any effect on its electrophoretic mobility. Inhibition of the mobility shift did not significantly affect tyrosine phosphorylation of IRS-1 or downstream insulin signaling. In contrast, blockade of IRS-1 degradation resulted in sustained activation of Akt, p70 S6 kinase, and mitogen-activated protein (MAP) kinase during prolonged insulin treatment. These results indicate that insulin-induced serine/threonine phosphorylation and degradation of IRS-1 are mediated by a rapamycin-sensitive pathway, which is downstream of PI 3-kinase and independent of ras/MAP kinase. The pathway leads to degradation of IRS-1 by the proteasome, which plays a major role in down-regulation of certain insulin actions during prolonged stimulation.


Asunto(s)
Acetilcisteína/análogos & derivados , Cisteína Endopeptidasas/metabolismo , Insulina/farmacología , Complejos Multienzimáticos/metabolismo , Fosfoproteínas/metabolismo , Transducción de Señal/efectos de los fármacos , Sirolimus/farmacología , Células 3T3 , Acetilcisteína/farmacología , Adenoviridae/genética , Adipocitos/metabolismo , Animales , Línea Celular , Desoxiglucosa/metabolismo , Embrión de Mamíferos , Inhibidores Enzimáticos/farmacología , Expresión Génica , Humanos , Proteínas Sustrato del Receptor de Insulina , Riñón , Ratones , Complejos Multienzimáticos/antagonistas & inhibidores , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Fosforilación , Complejo de la Endopetidasa Proteasomal , Transfección
16.
Clin Oncol (R Coll Radiol) ; 27(12): 732-40, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26160258

RESUMEN

AIMS: Adenoid cystic carcinoma of the lower respiratory tract is a rare indolent neoplasm with prolonged survival, propensity for recurrences and metastasis years after initial therapy. We aim to study a 1,700-bed single tertiary academic hospital's long-term experience with ACC of the lower respiratory tract from the larynx to the lungs and review published literature on this subject. MATERIALS AND METHODS: We analysed the clinicopathology, treatment options and outcome in 33 patients and reviewed the published literature over the last five decades. RESULTS: The tumour has no gender predilection, a peak incidence in the fifth decade and is not related to smoking. Insidious symptoms are often treated as benign obstructive airway disease and infection; negative signs and normal chest X-rays delayed diagnosis. The tumour was distributed most commonly in the trachea followed by main bronchi, lobar bronchi and larynx. About 22% of patients required emergent bronchoscopic intervention to secure airway patency before definitive therapy with surgery or/and radiotherapy. A high proportion of resected specimens had positive margins. Overall survival and disease-free survival rates at 5 years were 81 and 62%, respectively, and at 10 years 70 and 54%, respectively. Prolonged good palliation was achieved for patients with unresectable lesions with radiation and wide armamentarium of endoscopic therapy. CONCLUSIONS: In time, many patients eventually succumb to this disease. However, advances in medical skill and technology have prolonged survival while maintaining a good quality of life. Adenoid cystic carcinoma of the respiratory tract is a chronic life-long disease that may require interval intensive therapy. The challenge is to find the best therapeutic regimen aiming for a 'true' cure. Further study on the mutational landscape of adenoid cystic carcinoma may provide potential avenues for novel treatments to address a chemoresistant cancer.


Asunto(s)
Carcinoma Adenoide Quístico/terapia , Recurrencia Local de Neoplasia/terapia , Calidad de Vida , Neoplasias del Sistema Respiratorio/terapia , Adulto , Anciano , Carcinoma Adenoide Quístico/patología , Terapia Combinada , Manejo de la Enfermedad , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Cuidados Paliativos , Pronóstico , Neoplasias del Sistema Respiratorio/patología , Estudios Retrospectivos , Tasa de Supervivencia , Factores de Tiempo , Adulto Joven
17.
Nucl Med Biol ; 42(4): 387-94, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25633247

RESUMEN

INTRODUCTION: Glucokinase (GK) is potentially a target for imaging of islets of Langerhans. Here we report the radiosynthesis and preclinical evaluation of the GK activator, [(11)C]AZ12504948, for in vivo imaging of GK. METHODS: [(11)C]AZ12504948 was synthesized by O-methylation of the precursor, AZ125555620, using carbon-11 methyl iodide ([(11)C]CH3I). Preclinical evaluation was performed by autoradiography (ARG) of human tissues and PET/CT studies in pig and non-human primate. RESULT: [(11)C]AZ12504948 was produced in reproducible good radiochemical yield in 28-30 min. Radiochemical purity of the formulated product was >98% for up to 2 h with specific radioactivities 855 ± 209 GBq/µmol (n=8). The preclinical evaluation showed some specificity for GK in liver, but not in pancreas. CONCLUSION: [(11)C]AZ12504948 images GK in liver, but the low specificity impedes the visualization of GK in pancreas. Improved target specificity is required for further progress using PET probes based on this class of GK activators.


Asunto(s)
Azetidinas/síntesis química , Benzamidas/síntesis química , Activadores de Enzimas/síntesis química , Glucoquinasa/metabolismo , Hígado/enzimología , Imagen Molecular/métodos , Páncreas/enzimología , Animales , Azetidinas/química , Benzamidas/química , Técnicas de Química Sintética , Activadores de Enzimas/química , Humanos , Hígado/diagnóstico por imagen , Macaca fascicularis , Masculino , Páncreas/diagnóstico por imagen , Tomografía de Emisión de Positrones , Trazadores Radiactivos , Radioquímica , Porcinos , Tomografía Computarizada por Rayos X
18.
Neuroscience ; 297: 95-104, 2015 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-25841321

RESUMEN

Attention-deficit/hyperactivity disorder (ADHD) is a complex neurobehavioral disorder that is characterized by attention difficulties, impulsivity, and hyperactivity. A non-stimulant drug, atomoxetine (ATX), which is a selective noradrenaline reuptake inhibitor, is widely used for ADHD because it exhibits fewer adverse effects compared to conventional psychostimulants. However, little is known about the therapeutic mechanisms of ATX. ATX treatment significantly alleviated hyperactivity of pituitary adenylate cyclase-activating polypeptide (PACAP)-deficient (PACAP(-/-)) mice with C57BL/6J and 129S6/SvEvTac hybrid background. ATX also improved impaired novel object recognition memory and prepulse inhibition in PACAP(-/-) mice with CD1 background. The ATX-induced increases in extracellular noradrenaline and dopamine levels were significantly higher in the prefrontal cortex of PACAP(-/-) mice compared to wild-type mice with C57BL/6J and 129S6/SvEvTac hybrid background. These results suggest that ATX treatment-induced increases in central monoamine metabolism may be involved in the rescue of ADHD-related abnormalities in PACAP(-/-) mice. Our current study suggests that PACAP(-/-) mice are an ideal rodent model with predictive validity for the study of ADHD etiology and drug development. Additionally, the potential effects of differences in genetic background of PACAP(-/-) mice on behaviors are discussed.


Asunto(s)
Inhibidores de Captación Adrenérgica/uso terapéutico , Clorhidrato de Atomoxetina/uso terapéutico , Trastornos del Conocimiento/tratamiento farmacológico , Hipercinesia/tratamiento farmacológico , Trastornos de la Memoria/tratamiento farmacológico , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/deficiencia , Inhibición Prepulso/efectos de los fármacos , Estimulación Acústica , Análisis de Varianza , Animales , Monoaminas Biogénicas/metabolismo , Trastornos del Conocimiento/genética , Relación Dosis-Respuesta a Droga , Conducta Exploratoria/efectos de los fármacos , Hipercinesia/etiología , Trastornos de la Memoria/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microdiálisis , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/genética , Reconocimiento en Psicología/efectos de los fármacos
19.
FEBS Lett ; 458(3): 363-9, 1999 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-10570941

RESUMEN

To elucidate the mechanism of the circadian rhythm, genes differentially expressed during subjective day and night in the rat suprachiasmatic nucleus (SCN), a circadian oscillator in mammals, were surveyed by a differential display method. We isolated a novel gene, scop (SCN circadian oscillatory protein), that was expressed in a circadian manner in the SCN. SCOP protein is predominantly expressed in the brain and has domains including a pleckstrin homology domain, leucine-rich repeats, a protein phosphatase 2C-like domain and a glutamine-rich region. The structural feature of SCOP protein suggests its role in the intracellular signaling in the SCN.


Asunto(s)
Proteínas del Tejido Nervioso/genética , Proteínas Nucleares/genética , Núcleo Supraquiasmático/metabolismo , Secuencia de Aminoácidos , Animales , Ritmo Circadiano , Clonación Molecular , Regulación de la Expresión Génica , Immunoblotting , Masculino , Datos de Secuencia Molecular , Proteínas del Tejido Nervioso/química , Proteínas del Tejido Nervioso/metabolismo , Proteínas Nucleares/química , Fosfoproteínas Fosfatasas , ARN Mensajero/genética , Ratas , Ratas Wistar , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Alineación de Secuencia
20.
FEBS Lett ; 477(1-2): 106-12, 2000 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-10899319

RESUMEN

Genes differentially expressed in the subjective day and night in the rat suprachiasmatic nucleus (SCN) were surveyed by differential display. A gene homologous to human casein kinase 1epsilon (CK1epsilon) was isolated, which initially appeared to be expressed in the suprachiasmatic nucleus (SCN) in a circadian manner. We here describe the cDNA cloning of the rat CK1epsilon and characterization of the protein products. The rCK1epsilon is predominantly expressed in the brain including the SCN, binds and phosphorylates mPer1, mPer2, and mPer3 in vitro, and translocates mPer1 and mPer3, but not mPer2, to the cell nucleus depending on its kinase activity when coexpressed with these Per proteins in COS-7 cells.


Asunto(s)
Proteínas Quinasas/genética , Proteínas Quinasas/metabolismo , Empalme Alternativo/genética , Secuencia de Aminoácidos , Animales , Relojes Biológicos , Transporte Biológico , Células COS , Caseína Quinasas , Proteínas de Ciclo Celular , Núcleo Celular/metabolismo , Ritmo Circadiano , Clonación Molecular , Perfilación de la Expresión Génica , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Datos de Secuencia Molecular , Mutación/genética , Proteínas Nucleares/metabolismo , Proteínas Circadianas Period , Fosforilación , Unión Proteica , Proteínas Quinasas/química , ARN Mensajero/análisis , ARN Mensajero/genética , Ratas , Ratas Wistar , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Alineación de Secuencia , Núcleo Supraquiasmático/metabolismo , Factores de Transcripción
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