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1.
J Anim Physiol Anim Nutr (Berl) ; 98(4): 739-46, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24164218

RESUMEN

Succinate dehydrogenase (SDH), Ca(2+) ATPase, Lactate dehydrogenase (LDH), are involved in energy metabolism. These enzymes can be used as indicators of the energy capacity of aerobic cells. The study investigated the effects of L-carnitine supplementation on M. pectoralis superficialis, M. pectoralis profundus, M. extensor carpi radialis muscle and M. flexor carpi ulnaris. Twenty-eight racing pigeons hatched at the same time were divided randomly into three groups. Eight pigeons, which were used as the control group, were sacrificed at 92-day old. The remaining twenty pigeons continued training until they reached 157-day old, with half the pigeons getting 25 mg/head/day of L-carnitine, while the other half given the same amount of water. The pigeons were assessed by histochemical methods and reverse transcription polymerase chain reaction (RT-PCR). To assess influence of L-carnitine on muscle fibre composition and the performance of three genes' mRNA, this study applied SDH localization, SDH, Ca(2+) ATPase and LDH mRNA expression to examine the results after oral administration of L-carnitine in vivo in racing pigeons. The results showed that L-carnitine significantly elevated the amount of white muscle fibre type IIa (p < 0.05). The mRNA expression quantities of SDH and LDH gene was higher via RT-PCR method. However, the expression of Ca(2+) ATPase remains similar. In conclusion, appropriate oral administration of L-carnitine of 25 mg/pigeon/day will result in an improvement of muscles related to flying.


Asunto(s)
Carnitina/farmacología , Columbidae/fisiología , Fibras Musculares Esqueléticas/efectos de los fármacos , Envejecimiento/fisiología , Animales , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/fisiología , Fibras Musculares Esqueléticas/fisiología , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo
2.
Genet Mol Res ; 9(2): 1085-93, 2010 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-20568053

RESUMEN

Unlike other plants, bamboo (Bambusoideae) flowering is an elusive physiological phenomena, because it is unpredictable, long-periodic, gregarious, and uncontrollable; also, bamboo plants usually die after flowering. The flowering mechanism in Arabidopsis thaliana, a eudicot model species, is well established, but it remains unknown in bamboo species. We found 4470 and 3878 expressed sequence tags in the flower bud and vegetative shoot cDNA libraries, respectively, of the bamboo species, Bambusa oldhamii. Different genes were found expressed in bamboo flower buds compared to vegetative shoots, based on the Munich Information Center for Protein Sequences functional categorization; flowering-related genes were also identified in this species. We also identified Arabidopsis flowering-specific homologs that are involved in its photoperiod in this bamboo species, along with autonomous, vernalization and gibberellin-dependent pathways, indicating that bamboos may have a similar mechanism to control floral transition. Some bamboo expressed sequence tags shared high similarity with those of rice, but others did not match any known sequences. Our data lead us to conclude that bamboo may have its own unique flowering genes. This information can help us understand bamboo flowering and provides useful experimental methods to study the mechanisms involved.


Asunto(s)
Bambusa/genética , Etiquetas de Secuencia Expresada , Flores/genética , Arabidopsis/genética , Cruzamientos Genéticos , ADN Complementario/metabolismo , Biblioteca de Genes , Genes de Plantas , Modelos Genéticos , Oryza/genética , Brotes de la Planta , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
3.
Poult Sci ; 87(8): 1544-9, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18648047

RESUMEN

Nontyphoid Salmonella have a broad host range in poultry and mammals, and serovar Typhimurium is a threat to public health. In this study, normal and sick ducks and geese were collected from 12 farms in Taiwan to investigate the age-associated infection of Salmonella and Salmonella Typhimurium in Roman geese (Anser anser domesticus) and Pekin ducks (Anas platyrhynchos domesticus). In normal birds, the prevalence of Salmonella differed between species, and with age [e.g., 1-wk group, 37.5% (30/80) for ducks and 5.2% (6/116) for goslings (P < 0.05) vs. 4-wk group, 1% (1/96) for ducks and 12.1% (21/174) for geese]. Salmonella Typhimurium was identified from the visceral organs of moribund young geese suffering with colibacillosis and riemerellosis isolated from 2 goose farms (farm A and B, respectively). At farm B, 22.9% (27/118) of 4-wk geese with diarrhea were Salmonella Typhimurium-positive compared with 4.6% (8/174) of 4-wk normal geese. All Salmonella Typhimurium strains except one harbored a 94.7-kb virulence plasmid. Subcutaneous injection of Salmonella Typhimurium isolate 91NGL1 resulted in different clinical signs and pathogenesis between ducks and geese. In addition, the mean infectivity dose ratios of ducks to geese were 3.2 and 85.0 for 4- and 12-d birds, respectively, suggesting that goslings were more susceptible to Salmonella Typhimurium and resistance to Salmonella Typhimurium increased with age, especially for ducks. Therefore, Salmonella Typhimurium infection should be more common in goose farms than in duck farms, especially in the younger birds.


Asunto(s)
Patos , Gansos , Enfermedades de las Aves de Corral/microbiología , Salmonelosis Animal/microbiología , Salmonella typhimurium/crecimiento & desarrollo , Factores de Edad , Animales , Recuento de Colonia Microbiana , ADN Bacteriano/química , ADN Bacteriano/genética , Hibridación de Ácido Nucleico , Enfermedades de las Aves de Corral/epidemiología , Enfermedades de las Aves de Corral/inmunología , Prevalencia , Distribución Aleatoria , Salmonelosis Animal/epidemiología , Salmonelosis Animal/inmunología , Salmonella typhimurium/genética , Salmonella typhimurium/patogenicidad , Taiwán/epidemiología , Virulencia
4.
Eur J Surg Oncol ; 34(8): 906-910, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18166289

RESUMEN

AIM: Liver transplantation (LT) criteria for treatment of hepatocellular carcinoma (HCC) were refined to improved survival and disease-free rates. Adjuvant chemotherapy might eliminate disseminated tumor cells after removal of the primary liver cancer and thereby benefit LT recipients. Our purpose was to evaluate the effect of an adjuvant chemotherapy (gemcitabine and cisplatin) on outcome of patients treated with LT for HCC. METHODS: Of the 99 patients who underwent liver transplantation from October 2001 through February 2006, there were 58 with HCC. Nine patients with extra-hepatic metastasis and four who died for noncancer-related reasons were excluded. Three groups (total n=45) were compared: Group A (n=15) met the Milan criteria and did not receive study chemotherapy, Group B (n=13) did not fit the Milan criteria and did not receive chemotherapy, and Group C (n=17) did not fit the Milan criteria and received gemcitabine and cisplatin. RESULTS: The chemotherapy regimen was well tolerated. Leukopenia, the need for granulocyte colony-stimulating factor treatment, or both occurred in four patients. The disease-specific survival rates were better for groups A and C than for group B (p=0.02) and the disease-free survival rates were also better for groups A and C than for group B (p=0.01). CONCLUSIONS: Systemic gemcitabine and cisplatin may improve disease-specific and disease-free survival in HCC patients who do not meet the Milan criteria after LT.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Inmunosupresores/uso terapéutico , Neoplasias Hepáticas/tratamiento farmacológico , Carcinoma Hepatocelular/cirugía , Quimioterapia Adyuvante , Cisplatino/uso terapéutico , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapéutico , Supervivencia sin Enfermedad , Femenino , Humanos , Neoplasias Hepáticas/cirugía , Trasplante de Hígado , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Gemcitabina
5.
Poult Sci ; 86(8): 1651-5, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17626809

RESUMEN

Salmonella enterica causes a number of significant poultry diseases and is also a major pathogen in humans. Most poultry infected by Salmonella become carriers; infection may also be fatal, depending on the particular serovar and the age of the bird at infection. Younger birds are more susceptible to infection by Salmonella, so it is critical that hatcheries monitor birds. We developed a method to use hatched eggshell membranes (HEM) to assess contamination by Salmonella in poultry hatching cabinets and to evaluate the prevalence of Salmonella in a goose hatchery and rearing farm. Comparison of the Salmonella isolation rate in hatching cabinets using 3 sampling methods showed that the highest Salmonella contamination was detected in HEM, and that these results differed significantly from those obtained from fluff samples and cabinet swab samples (P < 0.05). Analysis of HEM was also used to evaluate Salmonella contamination in goose, chicken, and duck hatcheries. The lowest Salmonella-positive rate was found for the chicken hatchery, followed by the goose and the duck hatcheries (P < 0.05). Six serogroups of Salmonella were detected in the 3 hatcheries: A, B, C1, C2, D, and E. The distribution of these serogroups differed among the hatcheries. Salmonella serogroup C1 was the major serogroup found in geese, compared with serogroup B in chickens and ducks. However, Salmonella Typhimurium was dominant in 1 goose hatchery and also in geese from this hatchery that had been transferred to a farm. Antibiotic susceptibility analysis showed that Salmonella Typhimurium strains isolated from the farm geese with diarrhea showed significantly higher resistance to doxycycline, colistin, sulfamethoxazole-trimethoprin, and cephalothin than those isolated from the hatchery (P < 0.05). Therefore, HEM as a detection target can be used to monitor Salmonella contamination in hatching cabinets and also be used to assess Salmonella prevalence in poultry hatcheries and rearing farms.


Asunto(s)
Crianza de Animales Domésticos , Pollos/microbiología , Patos/microbiología , Gansos/microbiología , Salmonelosis Animal/microbiología , Salmonella enterica/aislamiento & purificación , Animales , Portador Sano , Cáscara de Huevo/microbiología , Enfermedades de las Aves de Corral/epidemiología , Enfermedades de las Aves de Corral/microbiología , Prevalencia , Salmonelosis Animal/epidemiología
8.
Eur J Surg Oncol ; 33(2): 239-42, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17174512

RESUMEN

AIMS: The prognosis for patients with advanced tumors invading the inferior vena cava (IVC) is dismal and surgical treatments for these tumors are challenging. A surgical approach that avoids sternotomy and thoracotomy for tumors invading the IVC even to the level of the hepatocaval junction would be extremely helpful. METHODS: The intrapericardial IVC was isolated via a transdiaphragmatic pericardial window using a transabdominal approach. Hepatectomy was then applied via an anterior approach until the IVC was seen. Total hepatic vascular exclusion was achieved by clamping the portal triad, intrapericardial IVC and infrahepatic IVC. We removed the primary tumor, the liver portion involved and the tumor thrombi, with segmental resection of the IVC. Vascular continuity was reestablished using a 20-mm-diameter polytetrafluoroethylene graft. RESULTS: Four patients with tumors invading the IVC were treated with this method. All underwent gross en-bloc tumor resections and all survived. CONCLUSION: This method for the resection of IVC tumors could avoid emboli dislodging from the tumor thrombi, prevent the complications of sternotomy, cardiopulmonary bypass and shorten operative times.


Asunto(s)
Neoplasias de la Corteza Suprarrenal/patología , Leiomiosarcoma/patología , Neoplasias Hepáticas/patología , Pericardio/cirugía , Procedimientos Quirúrgicos Vasculares/métodos , Vena Cava Inferior/cirugía , Neoplasias de la Corteza Suprarrenal/diagnóstico por imagen , Neoplasias de la Corteza Suprarrenal/cirugía , Carcinoma Corticosuprarrenal/diagnóstico por imagen , Carcinoma Corticosuprarrenal/patología , Carcinoma Corticosuprarrenal/cirugía , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/cirugía , Contraindicaciones , Hepatectomía , Humanos , Leiomiosarcoma/diagnóstico por imagen , Leiomiosarcoma/cirugía , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/cirugía , Invasividad Neoplásica , Radiografía , Esternón/cirugía , Toracotomía , Resultado del Tratamiento , Vena Cava Inferior/diagnóstico por imagen , Vena Cava Inferior/patología
10.
Transplant Proc ; 38(7): 2203-6, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16980043

RESUMEN

OBJECTIVES: Acute lung injury and inflammation can occur after hepatic ischemia/reperfusion (I/R). Little is known regarding the possible role of nitric oxide synthase expression in this complex type of lung injury. METHODS: Real-time polymerase chain reactions and immunohistochemistry were used to assess the mRNA and protein expression of eNOS and iNOS in lung tissue after I/R challenge to the liver. Ischemia was induced by clamping the hepatic artery and portal vein for 40 minutes. After flow was restored, the liver was reperfused for 300 minutes. Blood samples were collected to assay three inflammatory parameters: tumor necrosis factor (TNF)-alpha, hydroxyl radicals, and NO. Lung lavage samples were assayed for protein and myeloperoxidase. The expression of eNOS and iNOS in lung tissues (n = 3) was also evaluated after I/R challenge to the liver. The iNOS inhibitor aminoguanidine was also tested in this I/R model. RESULTS: Reperfusion of the liver produced increased blood concentrations of TNF, hydroxyl radicals, and NO (P < .001; n = 8). Bronchial lavage fluids showed higher levels of protein and myeloperoxidase in the I/R than in the sham-treated group (P < .01). eNOS expression was down-regulated and iNOS expression up-regulated in I/R lung tissues (n = 3). The iNOS inhibitor aminoguanidine (10 mg/kg) significantly attenuated the lung injury. CONCLUSIONS: I/R injury to the liver induced lung injury involving systemic inflammatory responses and iNOS expression. Administration of aminoguanidine significantly attenuated the injury, suggesting that iNOS expression may play a critical role in lung injury induced by I/R of the liver.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Circulación Hepática , Pulmón/enzimología , Óxido Nítrico Sintasa de Tipo III/genética , Óxido Nítrico Sintasa de Tipo II/genética , Daño por Reperfusión/genética , Animales , Cromatografía Líquida de Alta Presión , Modelos Animales de Enfermedad , Radical Hidroxilo , Masculino , Metilguanidina/metabolismo , Óxido Nítrico/metabolismo , ARN Mensajero/genética , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/enzimología , Factor de Necrosis Tumoral alfa/metabolismo
11.
Transplant Proc ; 38(7): 2216-20, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16980047

RESUMEN

UNLABELLED: Our objective was to investigate the mRNA and protein expressions of eNOS and iNOS in the mesenteric vascular bed after ischemia and reperfusion of the rat superior mesenteric artery (SMA) and the role of nitric oxide (NO) in the response of the vascular bed to vasoconstrictors following reperfusion of the SMA. METHODS: Real-time polymerase chain reaction and immunohistochemistry were used to monitor the mRNA and protein expression of eNOS and iNOS after I/R challenge to the rat SMA. Ischemia was induced by clamping the SMA for 40 minutes, after which the flow was restored and the vessels were reperfused for 300 minutes. Blood samples were collected for assays of lactic dehydrogenase, tumor necrosis factor (TNF), hydroxyl radical, and NO. After ischemia/reperfusion, the vascular beds were separated for analysis of the expression of eNOS and iNOS. The SMA with its associated intestinal tissue was isolated and perfused in vitro with Tyrode's solution (N = 8) then challenged with phenylephrine. RESULTS: Reperfusion of the SMA induced an increase in blood concentrations of lactic dehydrogenase (P < .001; N = 8), hydroxyl radical (P < .05), TNF (P < .001), and NO (P < .05). ENOS and iNOS mRNA expression increased 1.3 +/- 0.1-fold and 19.6 +/- 3.5-fold, respectively when compared to the sham-operated group. Protein expression increased 1.9 +/- 0.4-fold and 12.6 +/- 3.1-fold, respectively, after reperfusion (N = 3) when compared with sham-treated rats. In vitro challenge showed that administration of phenylephrine (10(-8) approximately 10(-4) nmol) produced vasoconstriction in a dose-related manner. Maximum contractile responses to phenylephrine were attenuated in reperfused SMA. Addition of the NOS inhibitor N(G)-nitro-L-arginine (L-NNA, 10(-4) M) resulted in full recovery of the response to phenylephrine. CONCLUSIONS: Ischemia/reperfusion of the SMA results in a decrease in vascular reactivity of the mesenteric vessels that is dependent on NOS expression by the intestinal vascular bed.


Asunto(s)
Intestino Delgado/irrigación sanguínea , Arteria Mesentérica Superior/fisiopatología , Óxido Nítrico Sintasa/genética , Daño por Reperfusión/fisiopatología , Animales , Inhibidores Enzimáticos/farmacología , L-Lactato Deshidrogenasa/sangre , Masculino , Arteria Mesentérica Superior/efectos de los fármacos , Óxido Nítrico/metabolismo , Nitroarginina/farmacología , Fenilefrina/farmacología , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/enzimología , Vasoconstricción/efectos de los fármacos
12.
Transplant Proc ; 38(7): 2221-5, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16980048

RESUMEN

UNLABELLED: Our objective was to investigate the potential protective effects of insulin on the liver injury induced in three ischemia and reperfusion (I/R) models. METHODS: Three I/R models were used: (1) I/R of the liver was produced in isolated, perfused rat livers; (2) in in situ I/R of the liver in rats, ischemia was induced by clamping off the hepatic artery and portal vein for 40 minutes, the flow then restored, and the liver reperfused for 90 minutes; (3) in in situ I/R of the liver in mice, ischemia was induced by clamping off the hepatic artery for 15 minutes, the flow then restored, and the liver reperfused for 45 minutes. In all three cases, blood samples collected before ischemia and after reperfusion were analyzed for sGOT. Plasma nitrate/nitrite, hydroxyl radicals, and tumor necrosis factor were also measured. In each model, a dose of insulin sufficient to induce euglycemia was administered to assess its protective effect on liver injury and inflammation. RESULTS: These I/R protocols resulted in a significant increase in sGOT and in three inflammatory parameters; nitric oxide, hydroxyl radicals, and tumor necrosis factor. Pretreatment with insulin did not attenuate the liver injury in any of the three I/R models. CONCLUSIONS: Although insulin has been reported to provide anti-inflammatory benefits by reducing oxidative and nitrosative stress and cytokine release, none of these protective effects was seen in the three I/R-induced liver injury models we tested.


Asunto(s)
Insulina/farmacología , Circulación Hepática/fisiología , Daño por Reperfusión/fisiopatología , Animales , Aspartato Aminotransferasas/sangre , Velocidad del Flujo Sanguíneo/efectos de los fármacos , Modelos Animales de Enfermedad , Arteria Hepática , Técnicas In Vitro , Circulación Hepática/efectos de los fármacos , Pruebas de Función Hepática , Masculino , Ratones , Ratas , Ratas Sprague-Dawley
13.
Dig Liver Dis ; 38(7): 498-502, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16702033

RESUMEN

BACKGROUND: The Acute Physiology and Chronic Health Evaluation II classification system has been extensively used for predicting the patient mortality in various diseases. However, its utilisation on the pyogenic liver abscess has not yet been well studied. AIMS: The purpose of this study was to validate this system on this high death rate disease. PATIENTS: A retrospective study was conducted to assess 314 patients with pyogenic liver abscesses admitted to tertiary medical centre in past 12 years. METHODS: The outcome measurement was the in-hospital mortality. A multiple logistic regression model was used to assess the association between mortality and Acute Physiology and Chronic Health Evaluation II score while controlling for the potential confounding factors. RESULTS: The overall in-hospital mortality was 8.3%. The mean Acute Physiology and Chronic Health Evaluation II score of the expired patients was higher (P<0.0001). The mortality rate increased rapidly when Acute Physiology and Chronic Health Evaluation II score >or=15. After controlling for the potential confounding factors, patient with high admission Acute Physiology and Chronic Health Evaluation II score >or=15 had a higher chance of in-hospital mortality (P<0.01). In addition, the primary liver cancer history is also a risk factor (P=0.03). CONCLUSIONS: The Acute Physiology and Chronic Health Evaluation II score and the primary liver cancer history predict the in-hospital mortality of the pyogenic liver abscess patient.


Asunto(s)
APACHE , Mortalidad Hospitalaria , Absceso Piógeno Hepático/complicaciones , Absceso Piógeno Hepático/mortalidad , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/mortalidad , Femenino , Humanos , Absceso Piógeno Hepático/microbiología , Absceso Piógeno Hepático/patología , Neoplasias Hepáticas/microbiología , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Pronóstico , Factores de Riesgo , Tasa de Supervivencia
15.
J Surg Res ; 99(1): 75-83, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11421607

RESUMEN

BACKGROUND: Telomerase is activated in most human cancers but is inactivate in adult somatic tissues except for some proliferating cell lineages. The maintenance of telomerase activity may be a critical step of cellular immortalization and transformation. MATERIALS AND METHODS: We analyzed the expression of human telomerase reverse transcriptase (hTERT) using in situ hybridization and compared it to Ki-67 immunoreactivity in 29 cases of papillary thyroid carcinoma (PTC) and 17 cases of benign thyroid disease. RESULTS: The hTERT messenger RNA (mRNA) was expressed in the cytoplasm of carcinoma cells with moderate (n = 10) to strong intensity (n = 10) in 69% (20 of 29) PTC cases. Human TERT was found in only 29% (5 of 17) cases of benign thyroid disease. Human TERT gene expression was preferentially detected in PTC (P = 0.021). The Ki-67 labeling index was observed in 16 cases of PTC (16 of 29; 55.2%). This result was significantly different from that of benign thyroid disease (P = 0.014). The Ki-67 labeling index related to the intensity of hTERT mRNA expression (r = 0.51; P = 0.005) and was inversely associated with the follicular variant of PTC (r = -0.413; P = 0.026). No statistically significant difference was found between hTERT expression and histological subtype of PTC. CONCLUSIONS: Our results demonstrated that expression of hTERT could be detected using in situ hybridization in PTCs and was significantly distinguishable from that of benign thyroid disease. Human TERT expression was related to the Ki-67 labeling index, indicating that coupling of telomerase activation with cell proliferation was the associated mechanism for tumorigenesis.


Asunto(s)
Carcinoma Papilar Folicular/metabolismo , Carcinoma Papilar/metabolismo , Antígeno Ki-67/metabolismo , ARN Mensajero/metabolismo , ARN , Telomerasa/genética , Neoplasias de la Tiroides/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales , Carcinoma Papilar/genética , Carcinoma Papilar/patología , Carcinoma Papilar Folicular/genética , Carcinoma Papilar Folicular/patología , Proteínas de Unión al ADN , Femenino , Expresión Génica , Humanos , Inmunohistoquímica , Hibridación in Situ , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Enfermedades de la Tiroides/genética , Enfermedades de la Tiroides/metabolismo , Enfermedades de la Tiroides/patología , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología
16.
Semin Perinatol ; 25(2): 94-9, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11339671

RESUMEN

Activities of endothelial nitric oxide synthase (eNOS) are developmentally regulated and its presence at birth may play a role in the transition of cardiopulmonary circulation. Antenatal dexamethasone (Dex) therapy accelerates fetal lung maturation. We speculate that Dex therapy may enhance pulmonary eNOS protein expression in the newborn. This article examines whether antenatal Dex therapy affected the expression of eNOS in the lungs of rat pups in the postnatal period. Time-dated pregnant Wistar rats were subjected to 2 doses of Dex (0.8 mg/kg, intramuscularly, daily) or equivalent volume of normal saline at the 18th and 19th gestational day and delivered naturally. The newborn pups were randomly assigned to 4 groups by age: days 1, 3, 5, and 7. After homogenization, abundance of eNOS protein in lungs was determined by Western blot analysis. There were 7 dams in each group. Mean body weights of the pups in the Dex group were lighter than those in the control at birth and remained stunted up to day 7 (5.68+/-0.47 g v 6.34+/-0.47 g, P <.01). However, there were no differences in wet lung weights and lung/body weight ratios between both groups in the study period. Abundance of eNOS protein expression decreased in both the control and Dex groups (P < .01). Pups that received antenatal Dex had 39% more in abundance of eNOS protein expression in lungs when compared to the control on day 1 (P < .05) but there were no differences between both groups from day 3 to 7. We conclude that antenatal Dex therapy enhances the abundance of eNOS protein expression in the lung at birth and could be a factor in improving respiratory functions in infants who received antenatal steroid therapy.


Asunto(s)
Animales Recién Nacidos , Dexametasona/farmacología , Glucocorticoides/farmacología , Pulmón/embriología , Pulmón/enzimología , Óxido Nítrico Sintasa/análisis , Animales , Western Blotting , Dexametasona/administración & dosificación , Femenino , Glucocorticoides/administración & dosificación , Pulmón/efectos de los fármacos , Óxido Nítrico Sintasa/metabolismo , Óxido Nítrico Sintasa de Tipo III , Embarazo , Ratas , Ratas Wistar
17.
J Agric Food Chem ; 49(5): 2619-22, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11368644

RESUMEN

Various flavor esters were obtained by using recombinant lipases from Staphylococcus epidermidis as a catalyst in an aqueous environment. These esters were enzymatically synthesized to overcome the problems associated with chemical processes. This study showed that the S. epidermidis lipases could catalyze ester synthesis from decyl alcohol and fatty acids of different chain length. The wild-type and mutant lipases (M419A and V649I) could efficiently catalyze the synthesis of decyl alcohol esters of unsaturated fatty acids. In contrast, the yield of decyl laurate was better by wild-type and mutant enzyme V6491, but mutant enzyme M419A only favored the synthesis of decyl myristate. The esterification of oleic acid and various carbon-chain-length alcohols from ethanol to hexadecanol increased up to decanol by wild-type and M419A mutant enzymes and reached an optimum for dodecanol by V6491 mutant enzyme. The enzyme is potentially useful in food industries such as dairy product flavoring.


Asunto(s)
Ácidos Grasos/biosíntesis , Lipasa/metabolismo , Staphylococcus epidermidis/enzimología , Esterificación , Aromatizantes/química , Mutación
18.
Arch Biochem Biophys ; 385(1): 179-85, 2001 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-11361015

RESUMEN

It has been proposed that 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase catalyzes the oxidation of ACC to ethylene via N-hydroxyl-ACC as an intermediate. However, due to its chemical instability the putative intermediate has never been isolated. Here, we have shown that a purified recombinant ACC oxidase can utilize alpha-aminoisobutyric acid (AIB), an analog of ACC, as an alternative substrate, converting AIB into CO2, acetone, and ammonia. We chemically synthesized the putative intermediate compound, N-hydroxyl-AIB (HAIB), and tested whether it serves as an intermediate in the oxidation of AIB. When [1-(14)C]AIB was incubated with ACC oxidase in the presence of excess unlabeled HAIB as a trap, no labeled HAIB was detected. By comparing the acetone production rates employing HAIB and AIB as substrates, the conversion of HAIB to acetone was found to be much slower than that of using AIB as substrate. Based on these observations, we conclude that ACC oxidase does not catalyze via the N-hydroxylation of its amino acid substrate. ACC oxidase also catalyzes the oxidation of other amino acids, with preference for the D-enantiomers, indicating a stereoselectivity of the enzyme.


Asunto(s)
Aminoácido Oxidorreductasas/metabolismo , Acetona/metabolismo , Aminoácido Oxidorreductasas/química , Ácidos Aminoisobutíricos/síntesis química , Ácidos Aminoisobutíricos/metabolismo , Amoníaco/metabolismo , Catálisis , Relación Dosis-Respuesta a Droga , Escherichia coli/metabolismo , Etilenos/metabolismo , Radicales Libres , Frutas/enzimología , Hidroxilación , Cinética , Modelos Químicos , Proteínas Recombinantes/metabolismo , Estereoisomerismo , Especificidad por Sustrato
19.
J Steroid Biochem Mol Biol ; 75(2-3): 159-66, 2000 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-11226832

RESUMEN

Dehydroepiandrosterone (DHEA), a major steroid secreted by the adrenal gland which decreases with age after adolescence, is available as a nutritional supplement. DHEA is known to have antiproliferative effects but the mechanism is unclear. In this study using BV-2 cells, a murine microglial cell line, we investigated the effect of DHEA on cell viability and the interaction between DHEA and glucose concentrations in the medium. We showed that DHEA inhibited cell viability and G6PD activity in a dose-dependent manner and that the effect of DHEA on cell viability was inversely associated with glucose concentrations in the medium, i.e. lowered glucose strongly enhanced the inhibition of cell viability by DHEA. DHEA inhibited cell growth by causing cell cycle arrest primarily in the G0--G1 phase, and the effect was more pronounced at zero glucose (no glucose added, G0) than high glucose (4.5 mg/ml of the medium, G4.5). Glucose deprivation also enhanced apoptosis induced by DHEA. At G4.5, DHEA did not induce formation of DNA ladder until it reached 200 microM. However, at G0, 100 microM DHEA was able to induce apoptosis, as evidenced by the formation of DNA ladder, elevation of histone-associated DNA fragmentation and increase in cells positively stained with annexin V-FITC and annexin V-FITC/propidium iodide. The interactions between DHEA and glucose support the contention that DHEA exerts its antiproliferative effects through alteration of glucose metabolism, possibly by inhibition of G6PD activity leading to decreased supply of ribose-5-phosphate for synthesis of DNA and RNA. Although DHEA is only antiproliferative at pharmacological levels, our results indicate that its antiproliferative effect can be enhanced by limiting the supply of glucose such as by energy restriction. In addition, the present study shows that glucose concentration is an important factor to consider when studying the antiproliferative and toxicological effects of DHEA.


Asunto(s)
Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Deshidroepiandrosterona/farmacología , Glucosa/metabolismo , Glucosafosfato Deshidrogenasa/metabolismo , Animales , Ciclo Celular/fisiología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Medios de Cultivo , Fragmentación del ADN , Relación Dosis-Respuesta a Droga , Glucosa/farmacología , Humanos , Ratones , Microglía/fisiología
20.
Endocrinology ; 140(12): 5609-18, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10579324

RESUMEN

We report here the study of the human CYP11A1 promoter in driving tissue-specific, developmentally and hormonally regulated reporter gene expression. A 4.4-kb fragment containing all known regulatory elements is more efficient than a short basal promoter fused to an upstream adrenal enhancer in driving reporter LacZ gene expression both in cell culture and in transgenic mice. The LacZ gene controlled by the 4.4- and 2.3-kb promoters was expressed in the adrenal cortex, testicular Leydig cells, ovarian corpora lutea, and granulosa cells. Transgene expression in the adrenals was stimulated by ACTH, indicating the presence of ACTH-responsive sequence. Beta-galactosidase activity was first detected in the adrenal primordia at 11.5 days postcoitum. Its expression continued throughout all stages of adrenal development in a pattern similar to that of the endogenous CYP11A1, which was expressed in all zones of the adrenal cortex, but was strongest in the X zone. The X zone grew before puberty but regressed afterward, as did the levels of CYP11A1 and LacZ gene expression in the X zone. Our study of the CYP11A1 promoter in transgenic mice led to characterization of the adrenocortical zones.


Asunto(s)
Corteza Suprarrenal/crecimiento & desarrollo , Enzima de Desdoblamiento de la Cadena Lateral del Colesterol/genética , Regulación del Desarrollo de la Expresión Génica , Regiones Promotoras Genéticas , beta-Galactosidasa/genética , Corteza Suprarrenal/embriología , Corteza Suprarrenal/metabolismo , Hormona Adrenocorticotrópica/farmacología , Animales , Células Cultivadas , Cuerpo Lúteo/metabolismo , Femenino , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Humanos , Células Intersticiales del Testículo/metabolismo , Masculino , Ratones , Ratones Endogámicos ICR , Ratones Transgénicos , ARN Mensajero/análisis , Proteínas Recombinantes de Fusión , Distribución Tisular
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