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2.
Transplant Proc ; 50(9): 2877-2881, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30401415

RESUMEN

BACKGROUND: Fibrosing cholestatic hepatitis (FCH) is an aggressive form of hepatitis C virus (HCV) recurrence after liver transplantation (LT). Most FCH cases are fatal, occurring as a secondary disease following rapidly progressive liver dysfunction and graft failure. We report a case of early-onset FCH after LT that was successfully treated using daclatasvir and asunaprevir. CASE REPORT: A 59-year-old woman underwent living donor LT for HCV-related liver cirrhosis. However, liver function was not improved after LT and gradually worsened. A liver biopsy was performed at 30 and 47 days after the living donor LT to identify the cause of the liver dysfunction. The first biopsy result showed no specific finding. However, combined treatment with pegylated interferon and ribavirin was started because of a high HCV viral load (> 8.0 log IU/mL). Nevertheless, liver function and HCV viral load deteriorated, and the second biopsy performed on postoperative day 47 revealed FCH. We converted the antiviral agents into daclatasvir and asunaprevir and performed plasmapheresis twice. Since then, the liver dysfunction and HCV viral load gradually improved, and HCV RNA clearance occurred at week 11 after treatment. The patient achieved a sustained virologic response at week 24 after completion of the treatment. CONCLUSION: Daclatasvir combined with asunaprevir can be a useful treatment option in potentially fatal FCH after LT.


Asunto(s)
Antivirales/administración & dosificación , Hepatitis C/tratamiento farmacológico , Imidazoles/administración & dosificación , Isoquinolinas/administración & dosificación , Trasplante de Hígado/efectos adversos , Sulfonamidas/administración & dosificación , Carbamatos , Quimioterapia Combinada/métodos , Femenino , Hepacivirus , Hepatitis C/inmunología , Humanos , Huésped Inmunocomprometido , Donadores Vivos , Persona de Mediana Edad , Pirrolidinas , Recurrencia , Valina/análogos & derivados
3.
Transplant Proc ; 50(3): 910-914, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29661461

RESUMEN

BACKGROUND: Although active tuberculosis (TB) is considered a contraindication for liver transplantation (LT), this is the only treatment in patients with liver failure and concurrent active TB. We report a case with successful urgent living-donor LT for irreversible liver failure in the presence of active TB. CASE PRESENTATION: A 48-year-old man, with a history of decompensated alcoholic liver cirrhosis, was presented with stupor. At admission, his consciousness had deteriorated to semi-coma, and his renal function also rapidly deteriorated to hepatorenal syndrome. A preoperative computed tomography scan of the chest revealed several small cavitary lesions in both upper lobes, and acid-fast bacillus stain from his sputum was graded 2+. Adenosine deaminase levels from ascites were elevated, suggesting TB peritonitis. A first-line anti-TB drug regimen was started immediately (rifampin, isoniazid, levofloxacin, and amikacin). An urgent living-donor LT was performed 2 days later. After LT, the regimen was changed to second-line anti-TB drugs (amikacin, levofloxacin, cycloserine, and pyridoxine). The sputum acid-fast bacillus stain tested negative on postoperative day 10. His liver function remained well preserved, even after the reversion to first-line anti-TB treatment. The patient recovered without any anti-TB medication-related complications and was discharged. CONCLUSIONS: LT can be prudently performed as a life-saving option, particularly for patients with liver failure and concurrent active TB.


Asunto(s)
Fallo Hepático/complicaciones , Trasplante de Hígado , Tuberculosis/complicaciones , Antituberculosos/uso terapéutico , Humanos , Isoniazida/uso terapéutico , Levofloxacino/uso terapéutico , Donadores Vivos , Masculino , Persona de Mediana Edad , Rifampin/uso terapéutico , Tuberculosis/tratamiento farmacológico
4.
Transplant Proc ; 49(5): 1192-1195, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28583555

RESUMEN

BACKGROUND: Post-operative respiratory failure is common in liver transplant patients, with a direct effect on graft and recipient outcomes. We present a case of successful treatment for a patient who had acute respiratory distress syndrome combined with septic shock after living-donor liver transplantation with veno-arterial-venous hybrid mode of extracorporeal membrane oxygenation (ECMO) support. METHODS: A 49-year-old male patient underwent successful emergency living-donor liver transplantation for acute-on-chronic liver failure associated with alcoholic liver cirrhosis. The patient was diagnosed with concurrent active pulmonary tuberculosis and tuberculosis peritonitis just before emergency liver transplantation. Intermittent post-operative small-bowel obstruction caused by adhesions from tuberculosis peritonitis was nonresponsive to conservative management. RESULTS: On post-operative day 114, we performed emergency adhesio-lysis because of bowel ischemia signs. However, the patient had progressive deterioration of arterial oxygenation despite conventional ventilatory support and nitric oxide gas inhalation, and septic shock resulted from aspiration pneumonia. Therefore, we decided to administer ECMO. After initiation of ECMO support, hemodynamic status, pneumonic consolidation, and oxygenation status gradually improved, and the patient was weaned from ECMO on the 11th day. Finally, the patient was discharged on post-transplant day 204. CONCLUSIONS: ECMO can be a beneficial rescue option for the management of refractory cardiopulmonary failure in liver transplant recipients. In addition, the hybrid mode of ECMO is a helpful salvage option when conventional modes of ECMO are inadequate.


Asunto(s)
Oxigenación por Membrana Extracorpórea/métodos , Trasplante de Hígado/efectos adversos , Síndrome de Dificultad Respiratoria/etiología , Síndrome de Dificultad Respiratoria/terapia , Choque Séptico/etiología , Insuficiencia Hepática Crónica Agudizada/cirugía , Humanos , Donadores Vivos , Masculino , Persona de Mediana Edad , Peritonitis Tuberculosa/complicaciones , Complicaciones Posoperatorias/etiología , Tuberculosis Pulmonar/complicaciones
5.
Br J Radiol ; 88(1052): 20150144, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25996578

RESUMEN

OBJECTIVE: To evaluate interfractional and intrafractional movement of patients with rectal cancer during radiotherapy with electronic portal imaging device (EPID) and surface infrared (IR) markers. METHODS: 20 patients undergoing radiotherapy for rectal cancer with body mass index ranging from 18.5 to 30 were enrolled. Patients were placed in the prone position on a couch with a leg pillow. Three IR markers were put on the surface of each patient and traced by two stereo cameras during radiotherapy on a twice-weekly basis. Interfractional isocentre movement was obtained with EPID images on a weekly basis. Movement of the IR markers was analysed in correlation with the isocentre movement obtained from the EPID images. RESULTS: The maximum right-to-left (R-L) movement of the laterally located markers in the horizontal isocentre plane was correlated with isocentre translocation with statistical significance (p = 0.018 and 0.015, respectively). Movement of the surface markers was cyclical. For centrally located markers, the 95% confidence intervals for the average amplitude in the R-L, cranial-to-caudal (C-C) and anterior-to-posterior (A-P) directions were 0.86, 2.25 and 3.48 mm, respectively. In 10 patients, intrafractional movement exceeding 5 mm in at least one direction was observed. Time-dependent systematic movement of surface markers during treatment, which consisted of continuous movement towards the cranial direction and a sail back motion in the A-P direction, was also observed. CONCLUSION: Intrafractional movement of surface markers has both cyclic components and time-dependent systematic components. Marker deviations exceeding 5 mm were mainly seen in the A-P direction. Pre- or post-treatment EPID images may not provide adequate information regarding intrafractional movement because of systematic movement in the A-P direction during radiotherapy. ADVANCES IN KNOWLEDGE: This work uncovered a sail back motion of patients in the A-P direction during radiotherapy. Pre- or post-treatment EPID images may not provide accurate positioning of patients in the A-P direction because of this time-dependent intrafractional motion.


Asunto(s)
Neoplasias del Recto/radioterapia , Adulto , Anciano , Femenino , Humanos , Rayos Infrarrojos , Masculino , Persona de Mediana Edad , Movimiento , Proyectos Piloto , Posición Prona , Factores de Tiempo
6.
Oncogene ; 34(35): 4624-34, 2015 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-25435367

RESUMEN

Medullary thyroid carcinoma (MTC) is a neuroendocrine tumor mainly caused by mutations in the rearranged during transfection (RET) proto-oncogene. For therapy of advanced MTC, the Food and Drug Administration recently approved vandetanib and cabozantinib, the tyrosine kinase inhibitors targeting RET, vascular endothelial growth factor receptor, epidermal growth factor receptor and/or c-MET. Nevertheless, not all patients respond to these drugs, demanding additional therapeutic strategies. We found that mortalin (HSPA9/GRP75), a member of HSP70 family, is upregulated in human MTC tissues and that its depletion robustly induces cell death and growth arrest in MTC cell lines in culture and in mouse xenografts. These effects were accompanied by substantial downregulation of RET, induction of the tumor-suppressor TP53 and altered expression of cell cycle regulatory machinery and apoptosis markers, including E2F-1, p21(CIP1), p27(KIP1) and Bcl-2 family proteins. Our investigation of the molecular mechanisms underlying these effects revealed that mortalin depletion induces transient MEK/ERK (extracellular signal-regulated kinase) activation and altered mitochondrial bioenergetics in MTC cells, as indicated by depolarized mitochondrial membrane, decreased oxygen consumption and extracellular acidification and increased oxidative stress. Intriguingly, mortalin depletion induced growth arrest partly via the MEK/ERK pathway, whereas it induced cell death by causing mitochondrial dysfunction in a Bcl-2-dependent manner. However, TP53 was not necessary for these effects except for p21(CIP1) induction. Moreover, mortalin depletion downregulated RET expression independently of MEK/ERK and TP53. These data demonstrate that mortalin is a key regulator of multiple signaling and metabolic pathways pivotal to MTC cell survival and proliferation, proposing mortalin as a novel therapeutic target for MTC.


Asunto(s)
Carcinoma Medular/metabolismo , Carcinoma Neuroendocrino/metabolismo , Proliferación Celular , Supervivencia Celular , Proteínas HSP70 de Choque Térmico/genética , Proteínas Mitocondriales/genética , Neoplasias de la Tiroides/metabolismo , Animales , Apoptosis , Carcinoma Medular/patología , Carcinoma Neuroendocrino/patología , Línea Celular Tumoral , Femenino , Proteínas HSP70 de Choque Térmico/metabolismo , Humanos , Sistema de Señalización de MAP Quinasas , Ratones Desnudos , Proteínas Mitocondriales/metabolismo , Trasplante de Neoplasias , Estrés Oxidativo , Proto-Oncogenes Mas , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Fase de Descanso del Ciclo Celular , Neoplasias de la Tiroides/patología , Activación Transcripcional , Proteína p53 Supresora de Tumor/metabolismo , Regulación hacia Arriba
7.
Cell Death Dis ; 5: e1524, 2014 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-25393480

RESUMEN

The oncogenic human papillomavirus (HPV) E6/E7 proteins are essential for the onset and maintenance of HPV-associated malignancies. Here, we report that activation of the cellular ubiquitin-proteasome system (UPS) by the omega-3 fatty acid, docosahexaenoic acid (DHA), leads to proteasome-mediated degradation of E6/E7 viral proteins and the induction of apoptosis in HPV-infected cancer cells. The increases in UPS activity and degradation of E6/E7 oncoproteins were associated with DHA-induced overproduction of mitochondrial reactive oxygen species (ROS). Exogenous oxidative stress and pharmacological induction of mitochondrial ROS showed effects similar to those of DHA, and inhibition of ROS production abolished UPS activation, E6/E7 viral protein destabilization, and apoptosis. These findings identify a novel role for DHA in the regulation of UPS and viral proteins, and provide evidence for the use of DHA as a mechanistically unique anticancer agent for the chemoprevention and treatment of HPV-associated tumors.


Asunto(s)
Antivirales/farmacología , Proteínas de Unión al ADN/metabolismo , Ácidos Docosahexaenoicos/farmacología , Proteínas Oncogénicas Virales/metabolismo , Proteínas E7 de Papillomavirus/metabolismo , Proteínas Represoras/metabolismo , Activación Enzimática/efectos de los fármacos , Regulación de la Expresión Génica , Células HeLa , Interacciones Huésped-Patógeno , Papillomavirus Humano 16/efectos de los fármacos , Papillomavirus Humano 16/fisiología , Papillomavirus Humano 18/efectos de los fármacos , Papillomavirus Humano 18/fisiología , Humanos , Complejo de la Endopetidasa Proteasomal/efectos de los fármacos , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteolisis/efectos de los fármacos , Especies Reactivas de Oxígeno/agonistas , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Ubiquitina/genética , Ubiquitina/metabolismo , Ubiquitinación/efectos de los fármacos
8.
Appl Biochem Biotechnol ; 173(8): 2254-66, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24972653

RESUMEN

Despite great advances in our understanding of the molecular causes of liver cancer, significant gaps still remain in our knowledge of the disease pathogenesis and development of effective strategies for early diagnosis and treatment. The present study was conducted to evaluate the chemopreventive activity of ellagic acid (EA) against experimental liver cancer in rats. This is the first report that implies a possible role of EA in controlling liver cancer through activation of mitochondrial outer membrane permeability via activating proteins such as Bax, bcl-2, cyt-C, and caspase-9, which play important roles in apoptosis. Downregulation of NF-κB, cyclin D1, cyclin E1, matrix metalloproteinases (MMP)-2, MMP-9, and proliferating cell nuclear antigen (PCNA) were noted in EA-treated experimental rats and controlled inflammation mediated liver cancer when compared to the diethylnitrosamine (DEN)-induced group. Transmission electron microscopy (TEM) analysis of the livers of experimental rats demonstrated that EA treatment renovated its internal architecture. Overall, these results demonstrate the value of molecular approaches in identifying the potential role of EA as an effective chemopreventive agent.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Ácido Elágico/administración & dosificación , Neoplasias Hepáticas/tratamiento farmacológico , Mitocondrias/efectos de los fármacos , Animales , Caspasa 3/genética , Caspasa 3/inmunología , Permeabilidad de la Membrana Celular/efectos de los fármacos , Ciclina D1/genética , Ciclina D1/inmunología , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/inmunología , Masculino , Mitocondrias/inmunología , FN-kappa B/genética , FN-kappa B/inmunología , Ratas , Ratas Wistar , Proteína X Asociada a bcl-2/genética , Proteína X Asociada a bcl-2/inmunología
9.
ScientificWorldJournal ; 2014: 682051, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25580459

RESUMEN

Second-look value engineering (VE) is an approach that aims to lower the costs of products for which target costs are not being met during the production stage. Participants in second-look VE typically come up with a variety of ideas for cost cutting, but the outcomes often depend on their levels of experience, and not many good alternatives are available during the production stage. Nonetheless, good ideas have been consistently generated by VE experts. This paper investigates past second-look VE cases and the thinking processes of VE experts and proposes a cost review process as a systematic means of investigating cost-cutting ideas. This cost review process includes the use of an idea checklist and a specification review process. In addition to presenting the process, this paper reports on its feasibility, based on its introduction into a VE training course as part of a pilot study. The results indicate that the cost review process is effective in generating ideas for later analysis.


Asunto(s)
Análisis Costo-Beneficio/métodos , Lista de Verificación , Artículos Domésticos/economía
10.
J Oral Rehabil ; 39(12): 931-40, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22994138

RESUMEN

The aim of this study was to compare the effects of three cryotherapeutic modalities (ethyl chloride spraying, ice block rubbing and cold gel packing) on facial skin temperature. Thirty healthy volunteers (15 men, 15 women; mean age, 29·4 ± 3·2 years) participated in this study. Each of the three modalities was randomly applied to the skin over the right masseter muscle. The skin surface temperature was recorded at baseline and every 5 min for 60 min after the application of one of the three cryotherapeutic modalities. Immediately after application, cold gel packing demonstrated the greatest reduction in surface temperature (10·6 °C), followed by ethyl chloride spraying (4·3 °C) and ice block rubbing (3·7 °C) (P < 0·001). During the 60-min post-application period, ethyl chloride spraying and ice block rubbing produced similar skin surface temperature changes. The skin surface remained coldest for the longest period of time after cold gel packing. The median time for recovery of the baseline temperature after application of the cold gel pack was about three to four times longer than that for the other modalities (P < 0·001). Ethyl chloride spraying and ice block rubbing resulted in less reduction and faster recovery of skin surface temperature than did cold gel packing. In conclusion, ethyl chloride spraying and ice block rubbing had a limited cooling effect on the facial skin tissue and could not reduce the skin surface temperature enough for local analgesia. Moreover, the cooling effect of cold gel packing was remarkable, but not sufficient for local analgesia.


Asunto(s)
Crioterapia/métodos , Cloruro de Etilo/administración & dosificación , Hielo , Temperatura Cutánea/fisiología , Adulto , Femenino , Geles , Humanos , Masculino , Distribución Aleatoria , Recalentamiento , Estadísticas no Paramétricas , Termografía
11.
East Asian Arch Psychiatry ; 22(3): 105-9, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23019283

RESUMEN

Providing intensive psychosocial intervention within the 5-year critical period following the first psychotic episode is important for both symptomatic and functional recovery. Recently, community mental health centres in Korea have begun to shift their main roles from care of those with chronic schizophrenia to early detection of and interventions for those with first-episode psychosis. This pioneering approach was initiated by the Seoul Mental Health Center, which established a community network, formed a clinical consortium with hospitals and clinics, and developed guidelines for early psychosis detection and management and for the Social Treatment for Early Psychosis (STEP) programme. The One-STEP programme, provided during hospitalisation, has been especially efficient in obtaining a high acceptance rate for community services. Several key issues are discussed with regard to the successful establishment of the close partnership between community mental health centres and hospitals / clinics.


Asunto(s)
Diagnóstico Precoz , Intervención Médica Temprana/métodos , Desarrollo de Programa/métodos , Centros Comunitarios de Salud Mental/organización & administración , Intervención Médica Temprana/organización & administración , Humanos , Trastornos Psicóticos/terapia , República de Corea
12.
AJNR Am J Neuroradiol ; 32(4): 671-6, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21372170

RESUMEN

BACKGROUND AND PURPOSE: The hippocampal atrophy of MDD has been known, but the region shape contractions of the hippocampus in MDD were inconsistent. Spheric harmonic shape analysis was applied to the hippocampus in female patients with unremitting MDD to evaluate morphometric changes of the hippocampus. MATERIALS AND METHODS: Shape analysis was performed by using T1-weighted MR imaging in 21 female patients with MDD and 21 age- and sex-matched healthy controls. Manually segmented hippocampi were parameterized, and the point-to-point-based group difference was compared by using the Hotelling T-squared test. The partial correlation analyses were tested between clinical variables and shape changes. RESULTS: Both hippocampal volumes were small in patients with MDD compared with healthy controls, and the right hippocampal volume was negatively correlated with the number of episodes at marginal significance. Regional shape contractions were found in the ambient gyrus, basal hippocampal head, posterior subiculum, and dorsal hippocampus of the left hemisphere. The right hippocampus showed a similar pattern but was less atrophic compared with the left hippocampus. A negative correlation was found between the HDRS and shape deformation in the CA3, ambient gyrus, posterior subiculum, and gyrus fasciolaris of the left hippocampus. CONCLUSIONS: We showed atrophy and regional shape contractions in the hippocampi of patients with MDD, which were more dominant on the left side. The causes of hippocampal damage could be the hypersecretion of glucocorticoids contributing to neuronal death or the failing of adult neurogenesis in the dentate gyrus.


Asunto(s)
Trastorno Depresivo Mayor/patología , Hipocampo/patología , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Adolescente , Adulto , Atrofia , Mapeo Encefálico , Femenino , Humanos , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Adulto Joven
14.
Transplant Proc ; 38(9): 2971-3, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17112877

RESUMEN

UNLABELLED: Whole blood levels 2 hours after Neoral (C2) administration were observed to correlate better with area under the curve (AUC(0-4)) than trough levels (C0), suggesting that C2 may be the best single time point predictor of Neoral absorption. Owing to concerns about drug toxicity due to excessive immunosuppression, C2 adjustments to target blood levels may represent an advance. The present study measured C2 and levels to determine which correlated more closely with AUC(0-4). METHODS: Between August 2003 and July 2004, 40 adult liver transplantations were performed in our center. All patients received Neoral twice daily. They were maintained at a C0 level of about 200 ng/mL. C0 levels were measured daily. C2 levels were estimated on postoperative days 3, 5, 7, 14, and 28. AUC(0-4) performed on postoperative days 3, 7, and 28 was calculated using the trapezoidal rule. RESULTS: The mean AUC(0-4), C0, C1, C2, C3, and C4 were 1100.3 +/- 484.8 ng/mL, 197.1 +/- 84.7 ng/mL, 240.7 +/- 166.2 ng/mL, 307.8 +/- 162.6 ng/mL, 302.8 +/- 138.9 ng/mL, and 300.3 +/- 142.8 ng/mL, respectively. C2 correlated with AUC(0-4) (R2 = 0.868: P < .05) better than C0 (R2 = 0.245: P < .05), C1 (R2 = 0.604: P < .05), or C4 (R2 = 0.583: P < .05). CONCLUSIONS: Neoral dose monitoring according to a mean C2 range of 307.8 +/- 162.6 ng/mL correlated better with AUC(0-4). Further studies are required to determine suitable C2 levels in liver transplant patients.


Asunto(s)
Ciclosporina/sangre , Ciclosporina/uso terapéutico , Trasplante de Hígado/fisiología , Adulto , Área Bajo la Curva , Monitoreo de Drogas/métodos , Humanos , Inmunosupresores/sangre , Inmunosupresores/uso terapéutico , Pruebas de Función Hepática , Trasplante de Hígado/inmunología , Análisis de Regresión , Estudios Retrospectivos
15.
Apoptosis ; 11(3): 401-11, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16520894

RESUMEN

No published data are available about the expression of peroxisome proliferator-activated receptor gamma (PPARgamma) and the role of PPARgamma in retinoblastoma protein (RB)-deficient human colorectal cancer (CRC) cells (SNU-C4 and SNU-C2A). Our aim was to investigate whether PPARgamma is expressed in SNU-C4 and SNU-C2A cells and to elucidate possible molecular mechanisms underlying the effect of pioglitazone, a synthetic ligand for PPARgamma, on cell growth in these cell lines. RT-PCR and Western blot analysis showed that both human CRC cell lines expressed PPARgamma mRNA and protein. Pioglitazone inhibited the cell growth of both cell lines through G2/M phase block and apoptosis. In addition, pioglitazone caused a down-regulation of the X chromosome-linked inhibitor of apoptosis (XIAP), Bcl-2, and cyclooxygenase-2 (COX-2) under conditions leading to PPARgamma down-regulation. These results suggest that pioglitazone may have therapeutic relevance or significance in the treatment of human CRC, and the down-regulation of XIAP, Bcl-2, and COX-2 may contribute to pioglitazone-induced apoptosis in these and other RB-deficient cell lines and tumors.


Asunto(s)
Apoptosis/fisiología , Neoplasias Colorrectales/metabolismo , Hipoglucemiantes/metabolismo , PPAR gamma/metabolismo , Proteína de Retinoblastoma/metabolismo , Tiazolidinedionas/metabolismo , Caspasas/metabolismo , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Ciclooxigenasa 2/metabolismo , Citocromos c/metabolismo , Activación Enzimática , Humanos , Ligandos , Pioglitazona , Poli(ADP-Ribosa) Polimerasas/metabolismo , Proteína de Retinoblastoma/genética
16.
Anim Reprod Sci ; 87(1-2): 133-41, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15885446

RESUMEN

This study was conducted to evaluate the effect of oxygen tension during IVM and/or IVC on developmental competence of porcine follicular oocytes. Prospective, randomized experiments were designed, and oocytes were matured, inseminated and cultured in vitro in the designated condition. In experiment 1, either high (20%) or low (7%) oxygen tension was used for IVM. The high oxygen significantly improved blastocyst formation (23% versus 13%; P<0.01) after IVF than the low oxygen. Such treatment, however, did not significantly (P>0.05) improve the rates of nuclear maturation (89% in each treatment), sperm penetration (62-72%), monospermic fertilization (56-67%), pronuclear formation (90-96%), cleavage (49-53%) and blastocyst cell number (31-32 cells). In experiment 2, the combined effect of oxygen tension during IVM and IVC of embryos was evaluated by a 2 x 2 factorial arrangement. Again, the high oxygen tension during IVM supported blastocyst formation more efficiently (P<0.01) than the low oxygen, and this was independent of oxygen tension during IVC (26-28% versus 15-16%). In oocytes matured under the high oxygen, a tendency to increase blastomere number (P=0.0630) was found, when the low oxygen was used for IVC after insemination (39-45 cells/blastocyst). In conclusion, the use of high oxygen tension (20% maintained by exposure to 5% CO2 in air) for IVM of porcine oocytes promoted blastocyst formation in vitro.


Asunto(s)
Fertilización In Vitro/veterinaria , Oocitos/fisiología , Oxígeno/administración & dosificación , Porcinos , Animales , Blastocisto/fisiología , Núcleo Celular/fisiología , Células Cultivadas , Femenino , Oocitos/ultraestructura , Interacciones Espermatozoide-Óvulo
18.
Theriogenology ; 57(7): 1819-28, 2002 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-12041686

RESUMEN

We conducted this study to examine whether serum starvation in culture contributes to better development of bovine reconstructed oocytes and to evaluate which serum-starved somatic cell is the most effective for cloned calf production. In Experiment 1, donor cells of four different types (cumulus cells, ear fibroblasts, oviduct cells and uterine cells) were either serum-starved or not before fusion with enucleated oocytes, and reconstructed oocytes were further cultured for 168 h. Regardless of serum starvation, cumulus cells or ear fibroblasts yielded higher (P < 0.05) rates of fusion than other cells (62.6-69.3 versus 33.3-38.7%). In the serum-starved group, the first cleavage after reconstruction was significantly increased in cumulus cells and ear fibroblasts, compared with oviduct cells (93.4-94.3 versus 78.8-86.0%), and oocytes reconstructed with either of these yielded more blastocysts than oocytes reconstructed with oviduct or uterine cells (40.6-43.8 versus 20.3-19.0%). We observed a similar pattern in the non-starved group, but we found a significant increase in blastocyst formation was found only in cumulus cells compared with other donor cells (42.6 versus 15.4-27.7%). Overall comparison showed that serum starvation increased the rates of cleavage and development to the blastocyst stage, but we found a statistical significance only in the cleavage rate (80.0 versus 89.5%). In Experiment 2, we transferred randomly selected 59 blastocysts that were developed from oocytes reconstructed with serum-starved cells to 44 synchronised recipients. Of those recipients, 23 became pregnant on Day 60 after transfer (52.3%) and 12 (27.3%) delivered cloned calves. The mean gestation length and birth weight was 275 +/- 8 days and 39.6 +/- 15.6 kg, respectively. Although there was no significant difference among donor cells, blastocysts that were derived from oocytes reconstructed with ear fibroblasts yielded the highest rates of pregnancy (50.0%) and delivery (27.3%). In conclusion, serum starvation is effective for improving preimplantation development of oocytes reconstructed with cumulus or ear fibroblast cells and it may positively influence on obtaining better pregnancy outcome.


Asunto(s)
Medio de Cultivo Libre de Suero , Técnicas de Transferencia Nuclear , Oocitos/fisiología , Animales , Animales Recién Nacidos , Blastocisto/fisiología , Bovinos , Células Cultivadas , Fase de Segmentación del Huevo , Transferencia de Embrión/veterinaria , Desarrollo Embrionario y Fetal , Trompas Uterinas/ultraestructura , Femenino , Fibroblastos/ultraestructura , Oocitos/ultraestructura , Folículo Ovárico/ultraestructura , Embarazo , Útero/ultraestructura
19.
J Nanosci Nanotechnol ; 2(6): 613-5, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12908423

RESUMEN

We formed a DNA network embedding ferromagnetic cobalt nanoparticles with a 12-nm diameter through a nanoscale self-assembly of DNA molecules on large-scale mica surfaces (12 mm x 12 mm); we then confirmed its structural characteristics with an atomic force microscope. Moreover, noncontact magnetic force microscope measurement revealed that some embedded cobalt nanoparticles have different directions of magnetization, similar to "bits" in magnetic data storage devices.


Asunto(s)
Cobalto/química , Cristalización/métodos , ADN/química , Magnetismo , Nanotecnología/métodos , Silicatos de Aluminio/química , Coloides/química , Sustancias Macromoleculares , Microscopía de Fuerza Atómica , Microesferas , Conformación Molecular , Tamaño de la Partícula , Propiedades de Superficie , Moldes Genéticos
20.
Endocrinology ; 142(12): 5116-23, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11713204

RESUMEN

The orphan nuclear receptor Nur77 (NR4A1) is a member of the nuclear receptor superfamily and plays an important role in the regulation of genes involved in steroidogenesis and cell death. Northern blot analysis revealed that the expression of Nur77 mRNA was increased after puberty in mouse testis, and hCG treatment of peripubertal animals induced this gene expression in the testis. Moreover, LH treatment induced a transient increase in Nur77 mRNA, and this induction was LH dose dependent in mouse Leydig tumor cell line, K28. Western blot analysis showed that LH transiently induced Nur77 protein. The protein kinase inhibitor H-89, bisindolymaleimide I, and wortmannin strongly inhibited this inductive effect of LH on Nur77 gene expression. Transient transfection assay demonstrated that LH significantly increased the Nur77 promoter-driven luciferase reporter activity in a dose-dependent manner, and LH also increased the activity of a luciferase reporter gene driven by a promoter containing multi copies of a Nur77-responsive element. Moreover, EMSA showed that Nur77 DNA-binding activity was increased in response to LH. Finally, overexpression of dominant negative Nur77 reduced LH-mediated progesterone biosynthesis. Taken together, these results demonstrate that LH induces Nur77 gene expression, and Nur77 may play an important role in the LH-mediated steroidogenesis in Leydig cells.


Asunto(s)
Proteínas de Unión al ADN/genética , Expresión Génica/fisiología , Células Intersticiales del Testículo/fisiología , Hormona Luteinizante/fisiología , Factores de Transcripción/genética , Animales , Línea Celular , ADN/metabolismo , Relación Dosis-Respuesta a Droga , Expresión Génica/efectos de los fármacos , Células Intersticiales del Testículo/metabolismo , Hormona Luteinizante/farmacología , Masculino , Ratones , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares , Regiones Promotoras Genéticas/fisiología , Receptores Citoplasmáticos y Nucleares , Receptores de Esteroides , Transducción de Señal/fisiología , Esteroides/biosíntesis , Testículo/crecimiento & desarrollo , Factores de Tiempo
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