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1.
Tohoku J Exp Med ; 250(3): 173-179, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32161251

RESUMEN

Common bile duct (CBD) stone is a relatively common but potentially life-threatening disease. Endoscopic sphincterotomy (EST) has been performed as standard therapy for CBD stones, but the rate of recurrence of CBD stones is high. Risk factors have been poorly defined, and no effective means for the prevention of the recurrence of CBD stones have been established so far. We aimed to identify significant risk factors for the recurrence of bile duct stones. This study included 477 patients (231 women; mean age, 80.5 years) who underwent EST and cleared CBD stones on cholangiography. A retrospective analysis was performed for the consecutively collected data. During the follow-up period of 6-75 months, the recurrence of CBD stones was observed in 99 patients (20.8%). The median time to the recurrence was 19.0 months (range 4-72 months). Multivariate analysis identified the need for mechanical lithotripsy, which was used for stone fragmentation, as a risk factor. Mechanical lithotripsy caused cholangiography-negative small residua. Notably, saline solution irrigation of the bile duct reduced the recurrence of CBD stones. These results demonstrate that subsequent biliary irrigation after stone removal may prevent the recurrence of CBD stones by clearing small residual fragments.


Asunto(s)
Conducto Colédoco/patología , Cálculos Biliares/prevención & control , Cálculos Biliares/cirugía , Solución Salina/uso terapéutico , Irrigación Terapéutica , Anciano de 80 o más Años , Conducto Colédoco/diagnóstico por imagen , Femenino , Cálculos Biliares/diagnóstico por imagen , Humanos , Estimación de Kaplan-Meier , Modelos Logísticos , Masculino , Análisis Multivariante , Recurrencia , Esfinterotomía Endoscópica , Ultrasonografía
2.
Nihon Shokakibyo Gakkai Zasshi ; 117(12): 1109-1118, 2020.
Artículo en Japonés | MEDLINE | ID: mdl-33298677

RESUMEN

An 88-year-old woman was referred to our hospital for autoimmune hepatitis in 2016. She was treated with prednisolone. In 2018, she was rehospitalized owing to hepatitis relapse. Steroid pulse therapy was performed. She exhibited good recovery of hepatitis, but was transferred to a convalescent ward in a general hospital because of decreased activity of daily life. After a month later, she had high fever and cough. She was diagnosed as having tuberculosis because of positive Mycobacterium tuberculosis polymerase chain reaction. At our first medical examination in 2016, we performed enzyme-linked immunospot and the result was undeterminable. There is an increase in the opportunities to use immunosuppressant and biologic agents for elderly patients. Our case report should contribute to future medical care for elderly patients who are at risk of latent tuberculosis infection.


Asunto(s)
Hepatitis Autoinmune , Mycobacterium tuberculosis , Tuberculosis , Anciano , Anciano de 80 o más Años , Ensayo de Immunospot Ligado a Enzimas , Femenino , Hepatitis Autoinmune/diagnóstico , Hepatitis Autoinmune/tratamiento farmacológico , Humanos , Prednisolona
3.
J Gastroenterol Hepatol ; 33(12): 1956-1960, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29791048

RESUMEN

BACKGROUND AND AIM: This study analyzed inflammatory bowel disease activity for 2 years after the Great East Japan Earthquake. METHODS: We compared the relapse rates of patients with ulcerative colitis or Crohn's disease 1 and 2 years after the earthquake with rates immediately after the earthquake. To evaluate continuous disease courses, we also performed multivariate time-to-event analyses from the time of the earthquake to the onset of additional treatments. RESULTS: Of 903 patients with ulcerative colitis or Crohn's disease in our previous study, we could evaluate 2-year courses in 677 patients (394 ulcerative colitis and 283 Crohn's disease). Compared with the relapse rates of ulcerative colitis and Crohn's disease immediately after the earthquake (15.8% and 7.0%, respectively), those in the corresponding periods in 2012 (2.5% and 1.1%, respectively) and 2013 (2.3% and 2.5%, respectively) significantly decreased. There were 226 patients who required additional treatments after the earthquake. Multivariate time-to-event analyses revealed that only patients who had experienced the death of family members or friends were likely to need additional treatments (hazard ratio = 1.77, 95% confidence interval = 1.25-2.47). No other factors had a significant influence. CONCLUSIONS: The relapse rates 1 and 2 years after the earthquake significantly decreased. The factors that influenced long-term relapse were different from those that influenced short-term relapse.


Asunto(s)
Colitis Ulcerosa/terapia , Enfermedad de Crohn/terapia , Desastres , Terremotos , Estrés Psicológico/psicología , Adulto , Colitis Ulcerosa/diagnóstico , Colitis Ulcerosa/epidemiología , Colitis Ulcerosa/psicología , Enfermedad de Crohn/diagnóstico , Enfermedad de Crohn/epidemiología , Enfermedad de Crohn/psicología , Femenino , Humanos , Japón/epidemiología , Masculino , Recurrencia , Inducción de Remisión , Estudios Retrospectivos , Factores de Riesgo , Estrés Psicológico/diagnóstico , Estrés Psicológico/epidemiología , Factores de Tiempo , Resultado del Tratamiento
4.
Tohoku J Exp Med ; 229(1): 53-9, 2013 01.
Artículo en Inglés | MEDLINE | ID: mdl-23238650

RESUMEN

Endoscopic resection has become a major curative treatment for early colorectal carcinoma without lymph node metastasis. However, lymph node metastasis, a poor prognostic factor in colorectal carcinoma, occurs in about 10% of the patients with submucosal invasive colorectal carcinoma. Therefore, it is important to identify a high-risk factor for lymph node metastasis in submucosal invasive colorectal carcinoma. This study was designed to identify the relationship between tumor budding with ß-catenin expression and lymph node metastasis in submucosal invasive colorectal carcinoma. We investigated the immunohistochemistry of tumor budding in the 142 patients who underwent surgical resection for submucosal invasive colorectal carcinomas between 1984 and 1999 and the expression pattern of ß-catenin in budding tumor cells. Accordingly, all the patients were followed up for at least 10 years or until death. Among the 142 patients, lymph node metastasis was detected in 14 patients (9.9%). Univariate analysis showed that tumor budding with ≥ 5 tumor cells or cell clusters with expression of ß-catenin in the nucleus was significantly associated with lymph node metastasis (P = 0.005). In contrast, tumor budding detected by hematoxylin and eosin staining was not associated with lymph node metastasis. Multivariate logistic regression analysis showed that tumor budding with ≥ 5 tumor cells or cell clusters with expression of ß-catenin in the nucleus was a significant risk factor for lymph node metastasis (odds ratio, 7.124; 95% confidence interval, 1.407-36.062). Thus, tumor budding associated with ß-catenin expression is a risk factor for lymph node metastasis in submucosal invasive colorectal carcinoma.


Asunto(s)
Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/patología , Mucosa Intestinal/patología , Metástasis Linfática/diagnóstico , Invasividad Neoplásica/patología , beta Catenina/metabolismo , Biomarcadores de Tumor/metabolismo , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/cirugía , Humanos , Inmunohistoquímica , Modelos Logísticos , Oportunidad Relativa , Valor Predictivo de las Pruebas , Pronóstico , Factores de Riesgo
5.
Ther Apher Dial ; 25(4): 502-512, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33029920

RESUMEN

Ulcerative colitis (UC) patients harbor activated myeloid leukocytes, which exacerbate and perpetuate UC by releasing inflammatory cytokines. Granulocyte and monocyte adsorptive apheresis (GMA) with an Adacolumn depletes elevated myeloid leukocytes, inducing efficacy with favorable safety. To understand how the clinical outcome with GMA is affected by prior corticosteroid treatment or concomitant immunomodulators, a retrospective multicenter study in 102 UC patients, who had not responded well to first-line medications was undertaken. The remission rates after a course of GMA therapy were significantly higher in corticosteroid-naïve patients compared with those with prior corticosteroid exposure. Absence of corticosteroid background was an independent predictive factor of response to GMA. Further, in corticosteroid-naïve patients, the 1-year cumulative sustained remission rate in patients who did not receive immunomodulators was significantly higher than in patients who received immunomodulators. Accordingly, multivariate analysis revealed that immunomodulator was associated with higher risk of relapse. In conclusion, GMA was an effective treatment for corticosteroid-naïve patients and the efficacy sustained longer in those not receiving immunomodulators during GMA. GMA fulfills the notion that apheresis is to induce disease remission by removing from the body factors known to perpetuate disease. In therapeutic settings, these findings should help better decision making and avoid futile use of medical resources.


Asunto(s)
Eliminación de Componentes Sanguíneos/métodos , Colitis Ulcerosa/terapia , Granulocitos , Monocitos , Corticoesteroides/uso terapéutico , Adsorción , Adulto , Colitis Ulcerosa/tratamiento farmacológico , Femenino , Humanos , Factores Inmunológicos/uso terapéutico , Masculino , Persona de Mediana Edad , Recurrencia , Inducción de Remisión , Estudios Retrospectivos , Factores de Riesgo
6.
Clin J Gastroenterol ; 14(1): 309-313, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32772241

RESUMEN

Situs inversus totalis (SIT) is a rare congenital anomaly in which all viscera are transposed to the opposite side of the body. This uncommon anatomy causes technical difficulties in endoscopic treatment. A 98-year-old woman with SIT was admitted to our hospital complaining of upper abdominal pain and fever. Blood examinations and findings of abdominal computed tomography imaging confirmed the diagnosis of acute pancreatitis and cholangitis associated with biliary stones. After recovering from pancreatitis and cholangitis with conservative treatment, she underwent therapeutic endoscopic retrograde cholangiopancreatography (ERCP) to remove the common bile duct (CBD) stones. The patient and the endoscopist were positioned in the usual ERCP position, and the scope was inserted into the duodenum with an approach in the direction opposite to the routine practice. Biliary cannulation was performed in the direction of 1 o'clock, and the cholangiography showed remarkably dilated CBD filled with numerous stones. Endoscopic papillary large balloon dilation was performed, and the CBD stones were successfully removed. There were no complications, such as bleeding, pancreatitis, or perforation. Over 3 years of follow-up, she had no recurrence of cholangitis or pancreatitis.


Asunto(s)
Cálculos Biliares , Pancreatitis , Situs Inversus , Enfermedad Aguda , Anciano de 80 o más Años , Cateterismo , Colangiopancreatografia Retrógrada Endoscópica , Dilatación , Femenino , Cálculos Biliares/complicaciones , Cálculos Biliares/diagnóstico por imagen , Cálculos Biliares/cirugía , Humanos , Situs Inversus/complicaciones , Situs Inversus/diagnóstico por imagen , Resultado del Tratamiento
7.
Tohoku J Exp Med ; 220(3): 207-15, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20208416

RESUMEN

The main goal of Crohn's disease (CD) treatment at present is to induce and maintain remission for as long as possible, and several approaches have been used as induction and maintenance therapies. There are no reports that have compared the effects on mid- and long-term prognosis among the induction and maintenance therapies, especially between infliximab, a chimeric antibody to tumor necrosis factor-alpha, and nutritional therapies. A total of 262 CD patients with induced remission were enrolled in the cohort study. Patients who failed to achieve remission, and patients who were lost to follow-up within 12 months were excluded. Induction therapies for CD included total elemental enteral nutrition, total parenteral nutrition, infliximab, prednisolone, and surgical resection. Maintenance therapies included home elemental diet, 5-aminosalicylates, immunomodulators, and scheduled infliximab therapy. We evaluated the possible predictive factors of relapse and surgical recurrence including the clinical backgrounds of the patients and medical therapies, using the Cox multivariate hazard analysis. The main factors that strongly affected the first relapse were scheduled infliximab therapy (hazard ratio (HR) = 0.24, p < 0.0001), surgical induction (HR = 0.19, p < 0.0001) and high frequency of previous relapse (HR = 2.56, p = 0.002). Penetrating (HR = 3.33, p = 0.009) and stricturing (HR = 6.60, p < 0.0001) disease behavior were main risk factors of surgical recurrence. Scheduled infliximab therapy is the most effective maintenance therapy in a real clinical setting with respect to the mid- and long-term prognosis.


Asunto(s)
Antiinflamatorios/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Enfermedad de Crohn/tratamiento farmacológico , Fármacos Gastrointestinales/uso terapéutico , Adolescente , Adulto , Estudios de Cohortes , Enfermedad de Crohn/patología , Enfermedad de Crohn/prevención & control , Enfermedad de Crohn/cirugía , Femenino , Humanos , Infliximab , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Recurrencia , Inducción de Remisión , Factores de Riesgo , Resultado del Tratamiento , Adulto Joven
8.
Biochem Biophys Res Commun ; 387(4): 784-8, 2009 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-19643082

RESUMEN

Sirtuin 1 (SIRT1) is the closest mammalian homologue of yeast silent information regulator 2 (Sir2) and has a role in lifespan modulation. Reportedly, SIRT1 is also linked to neurodegenerative diseases. However, there are limited studies that report the relation between SIRT1 and neurodegenerative diseases using in vivo transgenic (Tg) methods. In the present study, we generated neuron-specific enolase (NSE) SIRT1 Tg mice that overexpress human SIRT1 in neurons. We examined possible neuroprotective effects of SIRT1 overexpression and compared their higher brain functions with those of wild-type (WT) mice. Overexpression of SIRT1 did not have any neuroprotective effects against the neuronal damage induced by ischemia or 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). However, SIRT1 Tg mice exhibited a reference memory deficit. These findings suggest that an excessive expression of SIRT1 might induce the memory deficit in mice, but not neuroprotective effects.


Asunto(s)
Trastornos de la Memoria/genética , Enfermedades Neurodegenerativas/fisiopatología , Neuronas/enzimología , Sirtuinas/genética , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/farmacología , Animales , Isquemia Encefálica/complicaciones , Trastornos de la Memoria/fisiopatología , Ratones , Ratones Transgénicos , Enfermedades Neurodegenerativas/inducido químicamente , Enfermedades Neurodegenerativas/etiología , Enfermedades Neurodegenerativas/genética , Neuronas/fisiología , Neurotoxinas/toxicidad , Sirtuina 1 , Sirtuinas/metabolismo
9.
Biochem Biophys Res Commun ; 368(4): 948-54, 2008 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-18279657

RESUMEN

The Nrf2/ARE pathway plays a pivotal role in chemoprevention and neuroprotection. Here, we report that sesquiterpene lactones extracted from Calea urticifolia and feverfew increased enhancer activity of the ARE. ARE activation was dependent on the number of alpha,beta-unsaturated carbonyl groups each compound bears and calealactone A (CL-A) harboring 3 of those was the most potent ARE inducer. At subtoxic doses, CL-A induced expression of heme oxygenase-1 (HO-1) gene, one of ARE target genes, through activation of the Nrf2/ARE pathway involving transient ROS generation and activation of PI3-K/Akt and MAPK pathways. Interestingly, H(2)O(2)-induced ARE activation and HO-1 induction were potentiated by pretreatment with CL-A at lower concentrations, at which Nrf2/ARE activation by the compound was minimal. These results suggest a possibility that preconditioning by sesquiterpene lactone may enhance activation of the Nrf2/ARE pathway and induction of phase II detoxification/antioxidant enzymes upon oxidative stress, thereby resulting in increased resistance to oxidative damage.


Asunto(s)
Antioxidantes/fisiología , Factor 2 Relacionado con NF-E2/fisiología , Elementos de Respuesta/fisiología , Sesquiterpenos/farmacología , Animales , Asteraceae/química , Elementos de Facilitación Genéticos , Genes Reporteros , Hemo Oxigenasa (Desciclizante)/biosíntesis , Peróxido de Hidrógeno/farmacología , Lactonas/farmacología , Células PC12 , Ratas
10.
World J Gastroenterol ; 14(37): 5755-9, 2008 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-18837096

RESUMEN

Cowden's disease, one of the several hamartoma syndromes, is characterized by hyperplastic lesions and hamartomas distributed in the whole body. About thirty percent of patients with Cowden's disease have been reported to be complicated by malignant tumors. Based on the criteria of the International Cowden Consortium, this disease is mainly diagnosed as trichilemmoma of the face and oral mucosal papillomatosis. However, Cowden's disease patients themselves often do not recognize trichilemmoma of the face and oral mucosal papillomatosis. We report a case of Cowden's disease in a 33-year-old female patient who was diagnosed based on the characteristic findings at gastrointestinal endoscopy. Clinically, the patient was aware of having bloody stools. Multiple polyps found endoscopically in the esophagus, stomach, ileum, colon and rectum showed histopathologically hamartomatous changes and epithelial hyperplasia. Physical examination revealed oral papillomatosis and facial trichilemmomas. A germline mutation in exon 8 of the phosphatase and tensin homolog deleted on chromosome ten (PTEN) gene was found in this case. It was a point mutation of C to T at codon 1003 (CGA-->TGA, arginine-->stop codon). The characteristic findings on gastrointestinal endoscopy led us to a diagnosis of Cowden's disease. It has been reported that gastrointestinal polyposis with esophageal polyposis is found in about 85.7% of Japanese patients with Cowden's disease. The characteristic findings on gastrointestinal endoscopy can be a useful diagnostic clue to Cowden's disease.


Asunto(s)
Endoscopía Gastrointestinal , Enfermedades del Esófago/etiología , Enfermedades Gastrointestinales/etiología , Síndrome de Hamartoma Múltiple/patología , Poliposis Intestinal/etiología , Pólipos/etiología , Adulto , Análisis Mutacional de ADN , Diagnóstico Precoz , Enfermedades del Esófago/patología , Femenino , Enfermedades Gastrointestinales/patología , Mutación de Línea Germinal , Síndrome de Hamartoma Múltiple/complicaciones , Síndrome de Hamartoma Múltiple/genética , Humanos , Hiperplasia , Poliposis Intestinal/patología , Fosfohidrolasa PTEN/genética , Papiloma/etiología , Papiloma/patología , Mutación Puntual , Pólipos/patología , Gastropatías/etiología , Gastropatías/patología
11.
Antioxid Redox Signal ; 9(11): 2035-41, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17822366

RESUMEN

Hydrogen sulfide (H2S) can enzymatically be produced from cysteine in the brain. H2S functions as a synaptic modulator as well as a neuroprotectant from oxidative stress in the brain. Here we show that H2S specifically enhances the reducing activity in neurons and mouse neuroblastoma Neuro2a cells. An inhibitor of protein tyrosine kinase, genistein, suppresses the effect of H2S, suggesting that tyrosine kinase may be involved in the enhancement of reducing activity by H2S. The H2S-specific enhancement of the reducing activity in neurons may lead to a neurotrophic role in the brain.


Asunto(s)
Encéfalo/fisiología , Sulfuro de Hidrógeno/farmacología , Neuronas/efectos de los fármacos , Animales , Astrocitos/efectos de los fármacos , Encéfalo/citología , Células COS , Línea Celular Tumoral , Células Cultivadas , Chlorocebus aethiops , Relación Dosis-Respuesta a Droga , Embrión de Mamíferos , Genes Reporteros , Genisteína/farmacología , Sulfuro de Hidrógeno/antagonistas & inhibidores , Luciferasas/metabolismo , Ratones , Células 3T3 NIH , Neuroblastoma/patología , Neuronas/citología , Oxidación-Reducción/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Ratas , Ratas Sprague-Dawley , Sales de Tetrazolio/metabolismo
12.
BMJ Case Rep ; 20172017 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-28183711

RESUMEN

Although renal impairment is a rare complication of ulcerative colitis (UC), interstitial nephritis can occur as an idiosyncratic reaction to 5-aminosalicylate (5-ASA) treatment for UC. Monozygotic twins developed UC at ages 49 and 51, and they were separately treated at different medical institutes. They did not know that they had the same disease and were treated with the same drug (5-ASA). During the course of 5-ASA treatment, renal impairment diagnosed as interstitial nephritis occurred in both. Granulocyte/monocyte adsorption was initiated, UC remission was achieved and renal function deterioration subsided in both. Drug or treatment responses may be concordant in monozygotic twins with UC. Careful review is important before treatment to avoid serious adverse events.


Asunto(s)
Colitis Ulcerosa/complicaciones , Enfermedades en Gemelos , Nefritis Intersticial/inducido químicamente , Antiinflamatorios no Esteroideos/uso terapéutico , Colitis Ulcerosa/tratamiento farmacológico , Femenino , Humanos , Mesalamina/efectos adversos , Mesalamina/uso terapéutico , Persona de Mediana Edad , Gemelos Monocigóticos
13.
Neurosci Lett ; 400(1-2): 97-100, 2006 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-16529861

RESUMEN

We searched for genes differentially expressed in the frontal cortices of Alzheimer-type dementia (ATD) patients compared with those of non-ATD controls using DNA microarray and quantitative reverse transcription-polymerase chain reaction (RT-PCR) analyses. Here we show that the expression level of the autotaxin (also called lysophospholipase D or ecto-nucleotide pyrophosphatase/phosphodiesterase 2) gene was significantly greater in ATD cortices than in non-ATD cortices. In both ATD and non-ATD groups, the expression levels were greater in patients with the apoE epsilon3/epsilon4 genotype than in patients with the apoE epsilon3/epsilon3 genotype, although the differences were not statistically significant. These observations suggest that expression of the autotaxin gene and cell signaling by lysophosphatidic acid may be involved in the pathology of ATD, and that this cell signaling pathway may be a potential target of treatments for ATD.


Asunto(s)
Enfermedad de Alzheimer/patología , Lóbulo Frontal/metabolismo , Expresión Génica/fisiología , Complejos Multienzimáticos/genética , Fosfodiesterasa I/genética , Pirofosfatasas/genética , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Apolipoproteínas E/genética , Femenino , Humanos , Masculino , Complejos Multienzimáticos/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Fosfodiesterasa I/metabolismo , Hidrolasas Diéster Fosfóricas , Pirofosfatasas/metabolismo , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos
14.
J Neurosci ; 22(9): 3386-91, 2002 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-11978815

RESUMEN

Although hydrogen sulfide (H2S) is generally thought of in terms of a poisonous gas, it is endogenously produced in the brain. Physiological concentrations of H2S selectively enhance NMDA receptor-mediated responses and alter the induction of hippocampal long-term potentiation (LTP). Here we use cystathionine beta-synthase (CBS) knock-out mice to clearly show that CBS produces endogenous H2S in the brain and that H2S production is greatly enhanced by the excitatory neurotransmitter l-glutamate, as well as by electrical stimulation. This increased CBS activity is regulated by a pathway involving Ca2+/calmodulin. In addition, LTP is altered in CBS knock-out mice. These observations suggest that H2S is produced by CBS in response to neuronal excitation and that it may regulate some aspects of synaptic activity.


Asunto(s)
Sulfuro de Hidrógeno/metabolismo , Neuronas/metabolismo , Animales , Sitios de Unión/fisiología , Química Encefálica , Células COS , Calcio/metabolismo , Calmodulina/antagonistas & inhibidores , Calmodulina/metabolismo , Corteza Cerebral/química , Corteza Cerebral/metabolismo , Cistationina betasintasa/química , Cistationina betasintasa/deficiencia , Cistationina betasintasa/genética , Cisteína/análisis , Relación Dosis-Respuesta a Droga , Estimulación Eléctrica , Inhibidores Enzimáticos/farmacología , Ácido Glutámico/metabolismo , Ácido Glutámico/farmacología , Sulfuro de Hidrógeno/análisis , Técnicas In Vitro , Ionóforos/farmacología , Potenciación a Largo Plazo/fisiología , Ratones , Ratones Noqueados , Neuronas/citología , Neuronas/efectos de los fármacos , Pruebas de Precipitina , Unión Proteica/fisiología , Transducción de Señal/fisiología , Transmisión Sináptica/fisiología , Transfección
15.
Antioxid Redox Signal ; 7(5-6): 795-803, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15890027

RESUMEN

Nearly 300 years have passed since the first description of the toxicity of hydrogen sulfide (H(2)S) in 1713. Although many studies have been devoted to its toxicity, very little attention has been paid to understanding its normal physiological function. Relatively high concentrations of endogenous H(2)S, however, have recently been discovered in animal tissues, and its possible function as a biological messenger has been proposed. H(2)S enhances the activity of N-methyl-D-aspartate receptors and facilitates the induction of hippocampal longterm potentiation, a synaptic model for memory. H(2)S also increases intracellular concentrations of Ca(2+) in glia and induces Ca(2+) waves, which mediate glial signal transmission. Based on accumulating evidence for the reciprocal interactions between glia and neurons, it has been suggested that glia modulate synaptic transmission. Therefore, H(2)S may regulate synaptic activity by modulating the activity of both neurons and glia. In addition to a role in the signal transduction, H(2)S protects neurons from oxidative stress and in smooth muscle it may function as a relaxant. H(2)S, the toxic gas, may therefore be used as a multifunctional signaling mechanism under normal physiological conditions.


Asunto(s)
Sulfuro de Hidrógeno/metabolismo , Sulfuro de Hidrógeno/farmacología , Músculo Liso/efectos de los fármacos , Músculo Liso/fisiología , Fármacos Neuroprotectores/metabolismo , Fármacos Neuroprotectores/farmacología , Sinapsis/efectos de los fármacos , Animales , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Calcio/metabolismo , Humanos , Sulfuro de Hidrógeno/química , Músculo Liso/metabolismo , Fármacos Neuroprotectores/química , Sinapsis/metabolismo
16.
Biochem Pharmacol ; 66(3): 481-7, 2003 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-12907247

RESUMEN

We have previously reported purification of an extracellular polysaccharide GA3P, D-galactan sulfate associated with L-(+)-lactic acid, produced by a toxic marine microalga Dinoflagellate Gymnodinium sp. A(3) (GA3), and induction thereby of apoptosis on human myeloid leukemia K562 cells. In the present report, we show that the GA3P is a potent inhibitor of DNA topoisomerase (topo) I and topo II, irrespective of the presence or absence of the lactate group. Dextran sulfate also showed similar level of inhibition of topo I and topo II. We also demonstrated that, unlike camptothecin (CPT) or teniposide (VM-26), the inhibition of topo I or topo II by the polysaccharide does not involve accumulation of DNA-topo I/II cleavable complexes, clearly showing that they are not topo poisons but catalytic inhibitors with dual activity. Furthermore, the polysaccharide, when added to the reaction mixture with CPT or VM-26, inhibited stabilization of cleavable complex induced by the latter compounds. In addition, when added to the reaction mixture after the formation of the cleavable complexes by topo poisons, CPT for topo I and VM-26 for topo II, either GA3P or dextran sulfate diminished the amount of the complexes already accumulated, i.e. reversal of the reaction. These results suggest that the polysaccharides bind to the enzymes with high affinities, and that, as for topo I/II inhibition, the GA3P shares a common mechanism with dextran sulfate. As examined in vitro with a human cancer cell line panel, GA3P exhibited significant cytotoxicity against a variety of cancer cells. These findings show that the polysaccharide GA3P would prove to be a potential anticancer chemotherapeutic agent with dual activity of topo I and topo II catalytic inhibition.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Eucariontes/química , Polisacáridos/farmacología , Inhibidores de Topoisomerasa I , Inhibidores de Topoisomerasa II , Antineoplásicos/farmacología , División Celular/efectos de los fármacos , Daño del ADN , Humanos , Biología Marina , Células Tumorales Cultivadas
17.
Gan To Kagaku Ryoho ; 31(4): 495-500, 2004 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-15114689

RESUMEN

It has been established that etoposide (ETP), adriamycin (doxorubicin: DOX) and irinotecan (CPT-11), efficacious antitumor drugs widely used in clinics, target DNA topoisomerases (topo) in vivo. The present report attempts to explain why topos are the good targets of anticancer drugs from the point of view of enzymology of the enzymes and cell cycle behavior of tumor cells. Thus, many candidate anticancer drugs targeting topos are being screened, and preclinical and clinical studies thereof are being conducted world-wide and in Japan.


Asunto(s)
Antineoplásicos , Camptotecina/análogos & derivados , Ensayos de Selección de Medicamentos Antitumorales , Inhibidores de Topoisomerasa , Antineoplásicos/química , Camptotecina/química , Ciclo Celular , ADN-Topoisomerasas/química , Doxorrubicina/química , Etopósido/química , Humanos , Irinotecán , Células Tumorales Cultivadas/patología
18.
BMJ Open ; 3(2)2013.
Artículo en Inglés | MEDLINE | ID: mdl-23396562

RESUMEN

OBJECTIVE: Stress is thought to be one of the triggers of relapses in patients with inflammatory bowel disease (IBD). We examined the rate of relapse in IBD patients before and after the Great East Japan Earthquake. DESIGN: A retrospective cohort study. SETTINGS: 13 hospitals in Japan. PARTICIPANTS: 546 ulcerative colitis (UC) and 357 Crohn's disease (CD) patients who received outpatient and inpatient care at 13 hospitals located in the area that were seriously damaged by the earthquake. Data on patient's clinical characteristics, disease activity and deleterious effects of the earthquake were obtained from questionnaires and hospital records. PRIMARY OUTCOME: We evaluated the relapse rate (from inactive to active) across two consecutive months before and two consecutive months after the earthquake. In this study, we defined 'active' as conditions with a partial Mayo score=2 or more (UC) or a Harvey-Bradshaw index=6 or more (CD). RESULTS: Among the UC patients, disease was active in 167 patients and inactive in 379 patients before the earthquake. After the earthquake, the activity scores increased significantly (p<0.0001). A total of 86 patients relapsed (relapse rate=15.8%). The relapse rate was about twice that of the corresponding period in the previous year. Among the CD patients, 86 patients had active disease and 271 had inactive disease before the earthquake. After the earthquake, the activity indices changed little. A total of 25 patients experienced a relapse (relapse rate=7%). The relapse rate did not differ from that of the corresponding period in the previous year. Multivariate analyses revealed that UC, changes in dietary oral intake and anxiety about family finances were associated with the relapse. CONCLUSIONS: Life-event stress induced by the Great East Japan Earthquake was associated with relapse in UC but not CD.

19.
Antioxid Redox Signal ; 11(2): 205-14, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18754702

RESUMEN

Hydrogen sulfide (H2S) is recognized as a neuromodulator as well as neuroprotectant in the brain. H2S can be produced from cysteine by enzymes such as cystathionine beta-synthase. However, a mechanism for releasing H2S under physiologic conditions has not been identified. Here we show that H2S is released from bound sulfur, an intracellular store of sulfur, in neurons and astrocytes of mice and rats in the presence of physiologic concentrations of endogenous reducing substances glutathione and cysteine. The highest pH to release H2S from another sulfur store, acid-labile sulfur, which is localized mainly in mitochondria, is 5.4. Because mitochondria are not in the acidic condition, acid-labile sulfur may not be a physiologic source of H2S. Free H2S is immediately absorbed and stored as bound sulfur. Our novel method, using silver particles to measure free H2S, shows that free H2S is maintained at a low level in basal conditions. Alkalinization of the cytoplasm is required for effective release of H2S from bound sulfur, and this condition is achieved in astrocytes by the high concentrations of extracellular K+ that are normally present when nearby neurons are excited. These data present a new perspective on the regulation of H2S in the brain.


Asunto(s)
Encéfalo/metabolismo , Sulfuro de Hidrógeno/metabolismo , Animales , Astrocitos/metabolismo , Células Cultivadas , Cisteína/metabolismo , Citoplasma/metabolismo , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Ratones , Mitocondrias/metabolismo , Neuronas/metabolismo , Ratas
20.
Anal Biochem ; 338(1): 131-5, 2005 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-15707943

RESUMEN

While many investigations measuring oxidized nicotinamide adenine dinucleotide (NAD+) and reduced nicotinamide adenine dinucleotide (NADH) have been carried out on several mammalian tissues and blood cells, few reports have dealt with monolayers of cultured cells. Here we show a novel method to measure NAD+ and NADH in monolayers of a neuroblastoma cell line. The method was established by modifying a single extraction procedure originally developed for erythrocytes and an enzymatic cycling assay using a dye that absorbs in visible range. The following modifications were made. (i) Addition of 0.05% of a detergent, Triton X-100, to carbonate-bicarbonate extraction buffer enabled us to accurately measure cellular [NADH]/([NAD+]+[NADH]). (ii) Addition of N-ethyldibenzopyrazine ethyl sulfate salt (phenazine ethosulfate) immediately before the incubation suppressed the gradual decline of the sensitivity of the assay. The procedure presented here provides a simple and inexpensive measurement of NAD+ and NADH in cell monolayers.


Asunto(s)
NAD/análisis , Animales , Tampones (Química) , Calor , Ratones , NAD/aislamiento & purificación , Neuroblastoma/metabolismo , Octoxinol/farmacología , Oxidación-Reducción , Fenazinas , Sensibilidad y Especificidad , Células Tumorales Cultivadas
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