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1.
Braz J Biol ; 83: e273632, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37937624

RESUMEN

A great diversity of microorganisms in the soil plays an important role in the sustainability of agricultural production systems. Among these microorganisms are bacteria that have the ability to fix atmospheric nitrogen or mineralize phosphorus, thus making it easily assimilable for plants. Maize is the main crop in the highlands of Ecuador (above 2000 meters) and it is predominantly traditional, using native seeds and very little or no agrochemicals. The National Institute of Agricultural Research (INIAP) has a collection of bacteria collected from the rhizosphere of maize in the highlands of Ecuador that has not been taxonomically identified. This research aimed to carry out a biochemical and genetic characterization to establish the identity of the collected nitrogen-fixing and phosphorus-solubilizing bacteria and to understand better the diversity of microorganisms present in the root biome of Andean maize. The hypothesis consisted of determining if there is a difference in the bacteria associated with the rhizosphere of maize in the Andean region of Ecuador compared with other regions. The bacteria underwent classical biochemical characterization based on catalase, oxidase, urease, sulfates, indole, sulfate-indole motility (SIM), and lactose, among others, and genetic identification by 16S rDNA ribosomal gene sequencing, PCR, and SANGER sequencing. A great diversity of microorganisms associated with the rhizosphere of the crop was found, including the genera Agrobacterium, Bacillus, Stenotrophomonas, Acinetobacter, Brevundimonas, Pseudomonas, and Pseudoxanthomonas. INIAP conserves these bacteria in a bank of microorganisms associated with crops of economic importance. They are useful for the development of biofertilizers that could contribute to a more sustainable agriculture in the region.


Asunto(s)
Nitrógeno , Rizosfera , Fósforo , Zea mays , Ecuador , Raíces de Plantas , Bacterias/genética , Suelo/química , Productos Agrícolas , Indoles , Microbiología del Suelo , ARN Ribosómico 16S/genética
2.
Hum Exp Toxicol ; 37(4): 350-357, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28441892

RESUMEN

The aim of this study was to assess changes in bone mineral density (BMD) and cadmium (Cd) levels in blood and urine in individuals living in a Cd-contaminated area according to the type of osteoporosis medication over a three-year period. This follow-up study included 204 residents living in the vicinity of a closed copper refinery, who had been found to have elevated urinary or blood Cd levels. Cd levels in the blood and urine, as well as BMD, were measured every 6 months. After the first BMD measurement, individuals were prescribed antiresorptives such as alendronate or vitamin D and calcium, according to their BMD. Subjects were classified according to the type of medicine provided over the previous 6 months. General linear models controlling for other factors were used to evaluate the effects of each type of medication on the participants' Cd levels and BMD. Spinal BMD showed a significant increase in the antiresorptive group compared to the nontreatment group. Significant decreases in blood Cd levels were found in the vitamin D and calcium group, in comparison to the nontreatment group, as well as a marginally significant decrease in the antiresorptive group. The vitamin D and calcium group showed a significantly greater decrease in urinary Cd levels than the nontreatment group. In contrast, antiresorptive medication was found to have a negative effect on urinary Cd excretion. These results suggest that vitamin D and calcium treatment for osteoporosis lowers blood Cd levels more effectively and improves urinary Cd excretion.


Asunto(s)
Alendronato/uso terapéutico , Conservadores de la Densidad Ósea/uso terapéutico , Densidad Ósea/efectos de los fármacos , Cadmio/sangre , Cadmio/orina , Calcio/uso terapéutico , Suplementos Dietéticos , Contaminantes Ambientales/sangre , Contaminantes Ambientales/orina , Osteoporosis/tratamiento farmacológico , Vitamina D/uso terapéutico , Absorciometría de Fotón , Anciano , Carga Corporal (Radioterapia) , Cobre , Femenino , Humanos , Masculino , Metalurgia , Persona de Mediana Edad , Osteoporosis/diagnóstico , Osteoporosis/fisiopatología , Eliminación Renal , República de Corea , Factores de Tiempo , Resultado del Tratamiento
3.
Dis Esophagus ; 27(2): 116-21, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-23009198

RESUMEN

The prevalence of gastroesophageal reflux disease in Korea has been believed to be low, but the incidence of gastroesophageal reflux disease in Korea is expected to increase because of the longer life expectancy and more ingestion of westernized food. The aim of this study was to report differences in the risk factors of reflux esophagitis (RE) according to age in Korea. We prospectively recruited the subjects who had RE among those who visited a health promotion center for upper gastrointestinal cancer surveillance at Hallym Medical Center (five institutions) between January 2008 and February 2009. The enrolled study participants comprised 742 subjects with RE and 1484 healthy controls. The independent risk factors of RE in young and adult group were male sex, smoking, coffee, body mass index ≥ 25, hiatal hernia, and Helicobacter pylori negativity. The risk factors of RE in elderly group were smoking, coffee, and hiatal hernia. The risk factors for RE according to age group were found to differ. In elderly group, Helicobacter pylori infection was not a significant protective factor contrary to young and adult groups.


Asunto(s)
Esofagitis Péptica/epidemiología , Infecciones por Helicobacter/epidemiología , Hernia Hiatal/epidemiología , Sobrepeso/epidemiología , Fumar/epidemiología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Café , Estudios de Cohortes , Conducta de Ingestión de Líquido , Esofagitis Péptica/diagnóstico , Femenino , Helicobacter pylori , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Prospectivos , República de Corea/epidemiología , Factores de Riesgo , Factores Sexuales , Adulto Joven
4.
J Pathol ; 213(2): 170-9, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17768706

RESUMEN

NK/T-cell lymphoma (NKTL) is strongly associated with latent Epstein-Barr virus (EBV) infection. Recently, latent membrane protein 1 (LMP1), an EBV oncoprotein, was reported to activate the phosphatidylinositol-3 kinase (PI3K)/Akt pathway for cell survival. Because geldanamycin (GA) and its derivative, 17-allylamino-17-demethoxygeldanamycin (17-AAG), exhibit anti-tumour activity by degrading HSP90 client proteins, including Akt, we investigated the effect of GA and 17-AAG on the survival of NKTL cell lines. EBV-positive NKTL cell lines, Hank-1 and NK-YS, and an EBV-negative NK leukaemia cell line, NK-L, were treated with PI3K and Akt inhibitors, GA, and 17-AAG, and were subjected to apoptosis and cell viability assays, and immunoblot analysis. EBV-positive B-lymphoblastoid cell lines IM9 and LMP1-transfected IM9 (IM9-LMP1) were also included. Hank-1 and NK-YS cell viability was compromised and apoptosis was induced by LY294002 (PI3K inhibitor) or Akt inhibitor II. GA or 17-AAG administration resulted in the apoptosis of NKTL cells, accompanied by Akt and pAkt down-regulation, caspase 3 activation, and mitochondrial membrane potential disruption. The intrinsic level of pAkt was higher in EBV-positive NKTL cells than in EBV-negative NK-L, and GA or 17-AAG decreased the viability of NKTL cells more efficiently than NK-L. Moreover, IM9-LMP1 was more sensitive to Akt inhibitor II or HSP90 inhibitors than IM9. Importantly, GA showed little effect on the viability of normal peripheral NK cells as non-neoplastic counterparts for comparison. In conclusion, this study suggests that the PI3K/Akt pathway is frequently activated in EBV-positive NKTL and that therapeutic modalities based on targeting the PI3K/Akt pathway with HSP90 inhibitors could be useful for achieving NKTL control.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Benzoquinonas/farmacología , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Herpesvirus Humano 4/aislamiento & purificación , Lactamas Macrocíclicas/farmacología , Linfoma Extranodal de Células NK-T/patología , Supervivencia Celular , Regulación hacia Abajo/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Humanos , Linfoma de Células B/metabolismo , Linfoma de Células B/patología , Linfoma de Células B/virología , Linfoma Extranodal de Células NK-T/metabolismo , Potencial de la Membrana Mitocondrial/fisiología , Proteína Oncogénica v-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal , Células Tumorales Cultivadas
5.
Bioorg Med Chem Lett ; 16(4): 954-9, 2006 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-16297621

RESUMEN

Our efforts in seeking low molecular weight agonists of the antidiuretic peptide hormone arginine vasopressin (AVP) have led to the identification of the clinical candidate WAY-151932 (VNA-932). Further exploration of the structural requirements for agonist activity has provided another class of potent, orally active, non-peptidic vasopressin V2 receptor selective agonists exemplified by the 5,11-dihydro-pyrido[2,3-b][1,5]benzodiazepine as a candidate for further development.


Asunto(s)
Benzodiazepinas/clasificación , Benzodiazepinas/farmacología , Receptores de Vasopresinas/agonistas , Administración Oral , Animales , Benzazepinas/administración & dosificación , Benzodiazepinas/administración & dosificación , Evaluación Preclínica de Medicamentos , Estructura Molecular , Peso Molecular , Ratas , Ratas Sprague-Dawley , Relación Estructura-Actividad
6.
Water Sci Technol ; 51(10): 249-57, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16104428

RESUMEN

For this study, an automatic control system has been developed by using a neural network and internet-based remote monitoring system for efficient operation of plants that have a serious variance of influent loading and have difficulties in appropriate maintenance, just like small wastewater treatment plants in Korea. In the control algorithm, ORP was used as the main sensor for control. At the point where the ORP value was judged to reach the "nitrate knee" of denitrification and phosphorus release, ORP indicated the state of lower saturation read by the neural network and then changed the operating condition from the reduction state to the oxidation state. For example, if ORP indicates the state of higher saturation at the point of "nitrogen breakpoint" or "ammonia valley" of nitrification, the neural network reads it and cuts off the oxygen supply and mixing. The dORP data have been used as one of the main input for the neural network. After the operation of lab-scale cyclic aeration process using an automatic control system, it has been found that regardless of loading variance, more than 95% of organic matters and more than 60% of nitrogen and phosphorus have been removed. Assuming that an internet-connected computer and a basic web browser are available, this study has developed a remote monitoring system that can monitor the operating status of small plants or any troubles with them.


Asunto(s)
Redes Neurales de la Computación , Eliminación de Residuos Líquidos/métodos , Automatización , Monitoreo del Ambiente/métodos , Internet , Corea (Geográfico) , Nitrógeno/aislamiento & purificación , Oxígeno/análisis , Fósforo/aislamiento & purificación
7.
Water Sci Technol ; 50(6): 199-206, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15537008

RESUMEN

Many small-size wastewater treatment plants in Korea's rural communities are designed to remove organic and suspended matter only, and they generally show a large fluctuation in the influent loading compared to municipal wastewater treatment plants (MWWTPs). They also have no professional engineers stationed for efficient operation against mechanical breakdown. For those reasons, the wastewater treatment plants have low efficiency in treatment of nitrogen and phosphorus as well as organic matter. In order to solve those problems, this study developed an automatic control system and RMS (remote monitoring system), which can keep efficiency stable despite any change in the small plants' loading rates and are capable of removing nutrient materials such as nitrogen or phosphorus. According to the results of the Experimental SBR system of the automatic control program, complete nitrification was made under oxic conditions and denitrification occurred as NO3-N concentration decreased by 0.5 mg/l in anoxic conditions and excellent nitrogen removal efficiency was seen generally. The Experimental SBR system created "phosphate release and uptake" effectively and displayed phosphate-removing efficiency up to more than 80% as the concentration of effluent was kept low by 0.4 mg/l. RMS developed in this study transmits a plant's data and operation states to clients in remote locations in real-time interval through the Internet. Therefore, although you are in a remote location, it allows you to see if a plant is properly operated or there is any breakdown.


Asunto(s)
Reactores Biológicos , Nitrógeno/aislamiento & purificación , Fósforo/aislamiento & purificación , Aguas del Alcantarillado/microbiología , Eliminación de Residuos Líquidos/métodos , Automatización , Biomasa , Ciudades , Arquitectura y Construcción de Instituciones de Salud , Humanos , Hipoxia/metabolismo , Corea (Geográfico) , Nitratos/análisis , Nitratos/química , Nitratos/metabolismo , Nitritos/química , Nitritos/metabolismo , Nitrógeno/metabolismo , Fósforo/metabolismo , Aguas del Alcantarillado/química , Factores de Tiempo
8.
Br J Cancer ; 91(1): 11-7, 2004 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-15162146

RESUMEN

The risk of locoregional recurrence in resected gastric adenocarcinoma is high, but the benefit of adjuvant treatment remains controversial. In particular, after extended lymph node dissection, the role of radiotherapy is questionable. Since 1995, we started a clinical protocol of adjuvant chemoradiotherapy after D2 gastrectomy and analysed the patterns of failure for 291 patients. Adjuvant chemotherapy consisted of five cycles of fluorouracil and leucovorin, and concurrent radiotherapy was given with 4500 cGy from the second cycle of chemotherapy. With a median follow-up of 48 months, 114 patients (39%) showed any type of failure, and the local and regional failures were seen in 7% (20 out of 291) and 12% (35 out of 291), respectively. When the recurrent site was analysed with respect to the radiation field, in-field recurrence was 16% and represented 35% of all recurrences. Our results suggest that adjuvant chemoradiotherapy has a potential effect on reducing locoregional recurrence. Moreover, low locoregional recurrence rates could give a clue as to which subset of patients could be helped by radiotherapy after D2 gastrectomy. However, in order to draw a conclusion on the role of adjuvant radiotherapy, a randomised study is needed.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/radioterapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Gastrectomía , Recurrencia Local de Neoplasia , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/radioterapia , Adenocarcinoma/mortalidad , Adenocarcinoma/cirugía , Anciano , Quimioterapia Adyuvante , Supervivencia sin Enfermedad , Femenino , Fluorouracilo/administración & dosificación , Estudios de Seguimiento , Humanos , Leucovorina/administración & dosificación , Masculino , Persona de Mediana Edad , Radioterapia Adyuvante , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/cirugía , Tasa de Supervivencia , Insuficiencia del Tratamiento
9.
Ann Oncol ; 14(9): 1373-7, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12954575

RESUMEN

BACKGROUND: We report the results of postoperative chemoradiotherapy after curative resection in gastric cancer patients. PATIENTS AND METHODS: Patients with gastric cancer staged IB to IV(M0) were treated with chemoradiotherapy after curative resection with extensive (D2) lymph node dissection. Nodal metastases were observed in 261 (90%) patients. The chemotherapy consisted of fluorouracil 400 mg/m(2) plus leucovorin 20 mg/m(2) for 5 days, followed by 4500 cGy of radiotherapy for 5 weeks with fluorouracil and leucovorin on the first 4 days and the last 3 days of radiotherapy. Two 5-day cycles of chemotherapy were given 4 weeks after the completion of radiotherapy. RESULTS: Of 290 patients accrued, 229 (79%) patients completed chemoradiotherapy as planned. With a median follow-up of 49 months, 114 (34%) patients have relapsed: 33 (29%) locoregional relapses, 76 (67%) peritoneal relapses and 41 (36%) distant metastases. The 5-year overall and relapse-free survivals were 60% and 57%, respectively. Tolerance was acceptable, the main toxicity being neutropenia. CONCLUSIONS: This postoperative chemoradiotherapy after curative resection of gastric cancer was feasible, with acceptable toxicities. Whether this adjuvant therapy in gastric cancer patients that have undergone a D2 lymph node dissection impacts on survival or reduces the incidence of relapses remains to be studied.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/radioterapia , Fluorouracilo/uso terapéutico , Leucovorina/uso terapéutico , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/radioterapia , Adenocarcinoma/mortalidad , Adenocarcinoma/cirugía , Adulto , Anciano , Quimioterapia Adyuvante/efectos adversos , Terapia Combinada/efectos adversos , Fluorouracilo/efectos adversos , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Cuidados Posoperatorios , Pronóstico , Radioterapia Adyuvante/efectos adversos , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/cirugía , Resultado del Tratamiento
10.
J Chromatogr A ; 912(1): 119-25, 2001 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-11307974

RESUMEN

A new technique is proposed for the determination of bisphenol A in environmental water. The sample preparation consists of a single-step extraction of bisphenol A from a water sample with methylene chloride and the cyanomethyl derivatization of bisphenol A. 2,2'-Biphenol is used as an internal standard. Bisphenol A and biphenol can be quantitatively converted to their corresponding cyanomethyl ethers, which are then measured by gas chromatography with nitrogen-phosphorus detection. Peak shape and quantification of bisphenol A are excellent, with linear calibration curves over a range of 0.1-100 ng/ml. The detection limit is 0.1 ng/ml in water samples. The average recovery and RSD at a concentration of 5 ng/ml are 89.3 and 4.5%, respectively. The procedure is applicable to the quantification of bisphenol A in tap water, raw water and stream water.


Asunto(s)
Cromatografía de Gases/métodos , Fenoles/análisis , Contaminantes Químicos del Agua/análisis , Compuestos de Bencidrilo , Calibración , Espectrometría de Masas , Metilación , Estructura Molecular , Nitrógeno , Fenoles/química , Fósforo , Reproducibilidad de los Resultados
11.
Invest New Drugs ; 19(1): 81-3, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11291836

RESUMEN

Lovastatin, an inhibitor of mevalonate synthesis, demonstrated in vitro antitumor activity against a variety of human cancer cells, especially in gastric adenocarcinoma cells at pharmacologically achievable concentrations. To determine the antitumor activity of this drug in advanced measurable gastric adenocarcinoma as well as to assess the toxicities and the pharmacokinetic features, we carried out a phase II study of high-dose lovastatin. Patients received lovastatin 35 mg/kg/day for 7 consecutive days, with ubiquinone (60 mg qid p.o.) to prevent rhabdomyolysis. The treatment was repeated every 28 days. From March 1996 to January 1997, 16 patients (median age, 57 years; range, 34-68) were entered into the study, 14 of whom were evaluated for response and toxicity. No patient achieved a response. A total of 28 cycles were administered. The median number of cycles was 2 (range, 1 to 4). Anorexia was the most common toxicity (64%), but decreased oral intake was observed only in 3 cycles. Two patients developed myalgia with elevated muscle enzyme. When used in this dosage and schedule, lovastatin does not appear to be effective for patients with advanced gastric adenocarcinoma.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Antineoplásicos/administración & dosificación , Lovastatina/administración & dosificación , Neoplasias Gástricas/tratamiento farmacológico , Adulto , Anciano , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Evaluación de Medicamentos , Femenino , Humanos , Lovastatina/efectos adversos , Lovastatina/uso terapéutico , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
12.
Semin Ophthalmol ; 16(2): 66-9, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15491006

RESUMEN

PURPOSE: To evaluate the efficacy of transpupillary thermotherapy (TTT) for the treatment of occult choroidal neovascularization. METHODS: A retrospective, noncomparative case series of 57 eyes of 52 patients who presented with occult subfoveal CNV and were treated with TTT. RESULTS: 83% of eyes were either stable (+/- one line) or showed improvement in visual acuity. 83% of eyes showed stabilization of their exudative process after one TTT treatment as evidenced by resorption of subretinal and/or intraretinal exudate or hemorrhage. Nine percent of eyes developed classic CNV during the mean follow-up time of ten months. CONCLUSIONS: TTT appears to stabilize the exudative process in eyes with occult CNV. A prospective, sham-controlled, randomized study (TTT4CNV Clinical Trial) is currently underway to directly compare TTT to the natural history of occult CNV.


Asunto(s)
Neovascularización Coroidal/terapia , Hipertermia Inducida/métodos , Anciano , Exudados y Transudados , Femenino , Humanos , Masculino , Pupila , Estudios Retrospectivos , Resultado del Tratamiento , Agudeza Visual
13.
Toxicol Lett ; 115(2): 117-25, 2000 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-10802387

RESUMEN

We examined the effects of systemic administration of monosodium glutamate (MSG) or aspartate (ASP) on the memory retention and neuronal damage in the brains of adult mice. Compared with the control mice, a single intraperitoneal injection of either 4.0 mg/g MSG or 0.5 mg/g ASP after acquisition trial significantly shortened the response latency in the passive avoidance test, accompanying by the transient weight loss. Histopathological analysis of the brains of these mice revealed that neurons in the arcuate nucleus of hypothalamus were damaged markedly by MSG (4.0 mg/g) or ASP (0.5 mg/g). Other brain areas including cerebral cortex and hippocampus did not show any pathological changes. These findings suggest that systemic administration of MSG or ASP could impair memory retention and damage hypothalamic neurons in adult mice.


Asunto(s)
Ácido Aspártico/toxicidad , Aditivos Alimentarios/toxicidad , Hipotálamo/efectos de los fármacos , Memoria/efectos de los fármacos , Glutamato de Sodio/toxicidad , Animales , Ácido Aspártico/farmacología , Aditivos Alimentarios/farmacología , Hipotálamo/patología , Infusiones Parenterales , Masculino , Aprendizaje por Laberinto , Ratones , Neuronas/efectos de los fármacos , Neuronas/patología , Glutamato de Sodio/farmacología
14.
Clin Nucl Med ; 25(4): 268-72, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10750965

RESUMEN

PURPOSE: In this report, the authors assessed the clinical significance of decreased regional cerebral blood flow (rCBF) in the thalamus or cerebellar hemispheres in relation to gross motor performance in the children with cerebral palsy. MATERIALS AND METHODS: Thirty-six children with bilateral spastic cerebral palsy (BSCP) underwent brain SPECT. Visual analysis was used for the brain SPECT interpretation. The rCBF in the thalamus or cerebellum was graded as normal, mildly decreased, or severely decreased. A marked decrease or near absence of rCBF in the thalamus or cerebellum was considered as severely decreased. RESULTS: All 36 children with BSCP had hypoperfusion in the thalamus or cerebellar hemispheres. Eight of 20 children (40%) with mildly decreased rCBF on brain SPECT had mild developmental delays. On the other hand, only 1 of 16 children (6.3%) with severe hypoperfusion in the thalamus or cerebellum had a mild developmental delay, and the remaining 15 of 16 children (93.8%) had severe developmental delays. There was good correlation between the degree of developmental delay and the severity of hypoperfusion in the thalamus or cerebellum (P = 0.023). CONCLUSION: The measurement of rCBF by Tc-99m ethyl cysteinate dimer brain SPECT appears to be valuable in prognostication of gross motor development in children with BSCP.


Asunto(s)
Encéfalo/diagnóstico por imagen , Parálisis Cerebral/diagnóstico por imagen , Destreza Motora/fisiología , Tomografía Computarizada de Emisión de Fotón Único , Encéfalo/fisiopatología , Cerebelo/irrigación sanguínea , Parálisis Cerebral/fisiopatología , Circulación Cerebrovascular/fisiología , Cisteína/análogos & derivados , Discapacidades del Desarrollo/epidemiología , Femenino , Humanos , Lactante , Masculino , Compuestos de Organotecnecio , Valor Predictivo de las Pruebas , Radiofármacos , Tálamo/irrigación sanguínea
15.
Mol Cells ; 10(1): 18-24, 2000 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-10774742

RESUMEN

Chromosomal localization and sequence analysis of the 5S rRNA gene were carried out in five Capsicum species. Fluorescence in situ hybridization revealed that chromosomal location of the 5S rRNA gene was conserved in a single locus at a chromosome which was assigned to chromosome 1 by the synteny relationship with tomato. In sequence analysis, the repeating units of the 5S rRNA genes in the Capsicum species were variable in size from 278 bp to 300 bp. In sequence comparison of our results to the results with other Solanaceae plants as published by others, the coding region was highly conserved, but the spacer regions varied in size and sequence. T stretch regions, just after the end of the coding sequences, were more prominant in the Capsicum species than in two other plants. High G x C rich regions, which might have similar functions as that of the GC islands in the genes transcribed by RNA PolII, were observed after the T stretch region. Although we could not observe the TATA like sequences, an AT rich segment at -27 to -18 was detected in the 5S rRNA genes of the Capsicum species. Species relationship among the Capsicum species was also studied by the sequence comparison of the 5S rRNA genes. While C. chinense, C. frutescens, and C. annuum formed one lineage, C. baccatum was revealed to be an intermediate species between the former three species and C. pubescens.


Asunto(s)
Capsicum/genética , ADN de Plantas/genética , Plantas Medicinales , ARN Ribosómico 5S/genética , Secuencia de Bases , Preescolar , Mapeo Cromosómico , Clonación Molecular , ADN de Plantas/química , Genes de ARNr/genética , Variación Genética , Humanos , Hibridación Fluorescente in Situ , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie
16.
Cancer Lett ; 136(1): 33-40, 1999 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-10211936

RESUMEN

Cytotoxic lectins (KML-C) were isolated from an extract of Korean mistletoe [Viscum album C. (coloratum)] by affinity chromatography on a hydrolysed Sepharose 4B column, and the chemical and biological properties of KML-C were examined, partly by comparing them with a lectin (EML-1) from European mistletoe[Viscum album L. (loranthaceae)]. The hemagglutinating activity of KML-C was inhibited by N-acetyl-D-galactosamine and D-galactose at the minimum concentrations of 6.3 and 12.5 microM/ml, respectively. Further biochemical analyses indicated that KML-C consists of four chains (Mr = 27.5, 30, 31 and 32.5 kDa) which, in some of the molecules, are disulfide-linked, and that the chains of KML-C are distributed over a broad range of isoelectric points (pI), 8.0 to 9.0, whereas the range for EML-1 is 6.6-7.0. A difference was also observed between the N-terminal sequences of KML-C and EML-1. The isolated lectins showed strong cytotoxicity against various human and murine tumor cells, and the cytotoxic activity of KML-C was higher than that of EML-1. Tumor cells treated with KML-C exhibited typical patterns of apoptotic cell death, such as apparent morphological changes and DNA fragmentation, and its apoptosis-inducing activity was blocked by addition of Zn2+, an inhibitor of Ca2+/Mg2+ -dependent endonucleases, in a dose-dependent manner. These results suggest that KML-C is a novel lectin related to the cytotoxicity of Korean mistletoe, and that its cytotoxic activity against tumor cells is due to apoptosis mediated by Ca2+/Mg2+ -dependent endonucleases.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Lectinas/farmacología , Muérdago , Neoplasias/tratamiento farmacológico , Extractos Vegetales/farmacología , Plantas Medicinales , Animales , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Europa (Continente) , Humanos , Corea (Geográfico) , Lectinas/química , Lectinas/aislamiento & purificación , Ratones , Neoplasias/fisiopatología , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Lectinas de Plantas , Células Tumorales Cultivadas
17.
Endocrinology ; 138(4): 1392-9, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9075693

RESUMEN

The enzyme 3beta-hydroxysteroid dehydrogenase (3beta-HSD) is a key enzyme in the biosynthesis of steroid hormones. To date, this laboratory has isolated and characterized five distinct 3beta-HSD complementary DNAs (cDNAs) in the mouse (3beta-HSD I through V). These different forms are expressed in a tissue- and developmentally-specific manner and fall into two functionally distinct enzymes. 3beta-HSD I and III, and most likely II, function as dehydrogenase/isomerases, whereas 3beta-HSD IV and V function as 3-ketosteroid reductases. This study describes the isolation, characterization, and tissue-specific expression of a sixth member of this gene family, 3beta-HSD VI. This new isoform functions as an NAD+-dependent dehydrogenase/isomerase exhibiting very low Michaelis-Menten constant (Km) values for pregnenolone (approximately 0.035 microM) and dehydroepiandrosterone (approximately 0.12 microM). 3beta-HSD VI is the earliest isoform to be expressed during embryogenesis in cells of embryonic origin at 7 and 9.5 days postcoitum (pc), and is the major isoform expressed in uterine tissue at the time of implantation (4.5 days pc) and continues to be expressed in uterine tissue at 6.5, 7.5, and 9.5 days pc. 3beta-HSD VI is expressed in giant trophoblasts at 9.5 days pc and is expressed in the placenta through day 15.5 pc. In the adult mouse, 3beta-HSD VI appears to be the only isoform expressed in the skin and also is expressed in the testis, but to a lesser extent than 3beta-HSD I. Mouse 3beta-HSD VI cDNA is orthologous to human 3beta-HSD I cDNA. Human type I 3beta-HSD has been shown to be the only isoform expressed in the placenta and skin. The demonstration that mouse 3beta-HSD VI functions as a dehydrogenase/isomerase and is the predominant isoform expressed during the first half of pregnancy in uterine tissue and in embryonic cells suggests that this isoform may be involved in local production of progesterone, which is needed for successful implantation of the blastocyst and/or maintenance of early pregnancy.


Asunto(s)
Isoenzimas/aislamiento & purificación , Progesterona Reductasa/aislamiento & purificación , Glándulas Suprarrenales/química , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Southern Blotting , Western Blotting , Células COS , Deshidroepiandrosterona/metabolismo , Femenino , Gónadas/química , Humanos , Isoenzimas/química , Masculino , Ratones , Ratones Endogámicos C57BL/embriología , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Embarazo , Pregnenolona/metabolismo , Progesterona Reductasa/química , Útero/enzimología
18.
Planta Med ; 62(5): 405-9, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8923803

RESUMEN

To find a new compound with antiamnesic activity, we screened 29 natural products for their abilities to inhibit acetylcholinesterase and reverse scopolamine-induced amnesia. Among the plants tested Evodia rutaecarpa Bentham showed a strong inhibitory effect on acetylcholinesterase in vitro and an anti-amnesic effect in vivo. By sequential fractionation of E. rutaecarpa, the active component was finally identified as dehydroevodiamine hydrochloride (DHED). DHED inhibited acetylcholinesterase activity in a dose-dependent and non-competitive manner. The IC50 value of DHED is 37.8 microM. A single administration of DHED to rats (6.25 mg/kg) significantly reversed the scopolamine-induced memory impairment in a passive avoidance test. The antiamnesic effect of DHED was more potent than that of tacrine which is the only drug for Alzheimer's disease approved by FDA. This potent antiamnesic effect of DHED was thought to be due to the combined effects of acetylcholinesterase inhibition and the known cerebral blood flow enhancement. These results indicate that DHED has novel anti-cholinesterase and antiamnesic activities and might have therapeutic potential in various disorders including Alzheimer's disease.


Asunto(s)
Acetilcolinesterasa/metabolismo , Alcaloides/farmacología , Amnesia/tratamiento farmacológico , Memoria/efectos de los fármacos , Plantas Medicinales , Alcaloides/aislamiento & purificación , Amnesia/inducido químicamente , Animales , Masculino , Extractos Vegetales , Ratas , Ratas Sprague-Dawley , Escopolamina
19.
Biotechnol Bioeng ; 43(10): 978-86, 1994 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-18615445

RESUMEN

Extractive acetone-butanol-ethanol (ABE) fermentation was carried out successfully using pervaporation and a low-acid-producing Clostridium acetobutylicum B18. A pervaporation module with 0.17 m(2) of surface area was made of silicone membrane of 240 mum thickness. Pervaporation experiments using make-up solutions showed that butanol and acetone fluxes increased linearly with their concentrations in the aqueous phase. Fickian diffusion coefficients were constants for fixed air flow rates, and increased at higher sweep air flow rates. During batch and fed-batch fermentations, pervaporation at an air flow rate of 8 L/min removed butanol and acetone efficiently. Butanol concentration was maintained below 4.5 g/L even though Clostridium acetobutylicum B18 produced butanol steadily. Pervaporation could not remove organic acids efficiently, but organic acids did not accumulate because strain B18 produced little organic acid and recycled added organic acids efficiently. With pervaporation, glucose consumption rate increased compared to without pervaporation, and up to 160 g/L of glucose was consumed during 80 h. Cell growth was not inhibited by possible salt accumulation or oxygen diffusion through the silicone tubing. The culture volume was maintained relatively constant during fed-batch operation because of an offsetting effect of water and product removal by pervaporation and addition of nutrient supplements. (c) 1994 John Wiley & Sons, Inc.

20.
Cancer Chemother Pharmacol ; 33 Suppl: S128-33, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-8137473

RESUMEN

The aim of the present study was to deliver a high internal radiation dose to small hepatocellular carcinoma (HCC) lesions in an attempt to treat this disease. A total of 18 patients with HCC lesions measuring less than 4.5 cm in diameter (25 lesions) were treated with superselective intra-arterial injection of I-131-labeled Lipiodol (370-1,100 MBq in 3-5 ml) using a 5-F or coaxial catheter. All the lesions were nodular, multinodular, or hypervascular on pretreatment angiography. In all, 15 lesions that received over 180 Gy of cumulative radiation decreased in size in proportion to the Lipiodol retention on CT, and no pericapsular recurrence was found on angiography after 14-54 months of follow-up. In five patients who subsequently underwent surgery, 65% to 100% tumor necrosis was detected. No abnormal change in liver function tests or untoward clinical symptom of the lung, thyroid, or bone marrow was detected in patients who survived for more than 3 years after the treatment. Superselective high-dose internal radiation therapy of small HCC offers hope of treatment and long-term local control without complications.


Asunto(s)
Carcinoma Hepatocelular/radioterapia , Radioisótopos de Yodo/uso terapéutico , Neoplasias Hepáticas/radioterapia , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Inyecciones Intraarteriales , Radioisótopos de Yodo/administración & dosificación , Aceite Yodado/administración & dosificación , Masculino , Persona de Mediana Edad , Dosificación Radioterapéutica
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