Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 265
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Pharmazie ; 79(3): 64-66, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38872269

RESUMEN

Some macrolide antibiotics, which share a basic lactone ring structure, also exhibit anti-inflammatory actions in addition to their antibacterial activities. However, no study has directly compared anti-inflammatory effects on acute inflammation among macrolide antibiotics with the distinct size of the lactone ring. In this study, we evaluated and compared the anti-inflammatory activities of four 14-membered macrolides (erythromycin, clarithromycin, roxithromycin, oleandomycin), one 15-membered macrolide (azithromycin), and three 16-membered macrolides (midecamycin, josamycin, leucomycin) using a rat carrageenan-induced footpad edema model. All macrolide antibiotics were intraperitoneally administered to rats one hour before the induction of inflammatory edema with 1% λ -carrageenan. The anti-inflammatory effects on acute inflammation were evaluated by changing the edema volume. All 14-membered and 15-membered macrolide antibiotics significantly suppressed the development of edema. Conversely, none of the 16-membered macrolide antibiotics inhibited the growth of edema. In conclusion, compared to 16-membered macrolide antibiotics, 14-membered and 15-membered macrolide antibiotics have stronger anti-inflammatory effects. Further research should be done to determine why different lactone ring sizes should have distinct anti-inflammatory effects.


Asunto(s)
Antibacterianos , Antiinflamatorios , Carragenina , Edema , Inflamación , Macrólidos , Animales , Macrólidos/farmacología , Ratas , Edema/tratamiento farmacológico , Edema/inducido químicamente , Masculino , Antibacterianos/farmacología , Antiinflamatorios/farmacología , Inflamación/tratamiento farmacológico , Inflamación/inducido químicamente , Modelos Animales de Enfermedad , Ratas Sprague-Dawley , Antiinflamatorios no Esteroideos/farmacología
2.
J Radiol Prot ; 36(4): 865-884, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27739409

RESUMEN

The attribution of stochastic effects to exposure to ionizing radiation has been qualitatively discussed by introducing two distinct concepts of provability and probability. This study aims to develop a method of quantitatively assessing the provability of radiation-related cancers. To this end, the 'minimum provable dose' (MPD) was developed and applied to actual cancer mortality in Japan. The background lifetime risk of cancer mortality was calculated for the esophagus, stomach, colon, liver, lungs, skin, breasts, ovaries, bladder, and bone marrow as well as the age-specific risk coefficients reproducing those given in the 2007 Recommendations of the International Commission on Radiological Protection (ICRP). Comparing the relative ratio of MPDs, which was defined herein as the 'provability index' (PI), we quantitatively ranked radiation-related cancers for different tissues and organs predicated on provability for ages of 10, 30, 50, and 0-85+ years at exposure. We discuss the radiological protection of male emergency workers focusing on cancers highly prioritized according to the ranking (i.e. colon, bone marrow, and bladder). The present study proposed the system to quantitatively evaluate the level of radiological protection taking into account the variations of the background cancer risk on the provability of radiation-related cancers.


Asunto(s)
Neoplasias Inducidas por Radiación/etiología , Dosis de Radiación , Protección Radiológica/métodos , Radiación Ionizante , Femenino , Humanos , Incidencia , Japón/epidemiología , Masculino , Neoplasias Inducidas por Radiación/epidemiología , Exposición Profesional/efectos adversos , Monitoreo de Radiación , Medición de Riesgo , Factores de Riesgo
3.
Scand J Rheumatol ; 43(4): 291-5, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24650255

RESUMEN

OBJECTIVES: The American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) remission criteria for rheumatoid arthritis (RA) are more stringent than index-based criteria, making it more difficult to achieve a patient's global assessment (PGA) than an evaluator's global assessment (EGA). We investigated the reason for the discrepancy between the PGA and the EGA in a Japanese clinical cohort. METHOD: We assessed clinical and laboratory variables in our clinical cohort. The frequency of remission achievement according to the ACR/EULAR remission criteria and predictors of the discrepancy between the PGA and EGA were analysed. RESULTS: Of 370 patients with RA, 89 fulfilled PGA criteria and 167 patients fulfilled EGA criteria. The PGA was highly correlated with the visual analogue scale (VAS) pain score and non-inflammatory variables including Steinbrocker class and the Health Assessment Questionnaire Disability Index (HAQ-DI). Conversely, inflammatory variables, including swollen joint count (SJC), tender joint count (TJC), and C-reactive protein (CRP) levels, were significantly associated with the EGA. The main predictors of the discrepancy between the PGA and the EGA were patient's VAS pain score, SJC, and functional disability. CONCLUSIONS: Increased pain and functional disability led to a discrepancy towards a worse PGA than EGA, whereas increased SJC led to an accordance towards a worse EGA.


Asunto(s)
Artritis Reumatoide/diagnóstico , Evaluación de la Discapacidad , Índice de Severidad de la Enfermedad , Adulto , Anciano , Anciano de 80 o más Años , Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pacientes/psicología , Relaciones Médico-Paciente , Inducción de Remisión , Reumatología , Adulto Joven
4.
Ann ICRP ; 52(1-2): 9-15, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38143300

RESUMEN

The International Commission on Radiological Protection (ICRP) is recognised as the de-facto world authority in the field of radiological protection. The ICRP Recommendations have been used as a basis for regulations and policy in almost every country, and with the current review and revision of the System of Radiological Protection, it will continue to make significant contributions in radiation safety for patients, workers, the public, and the environment. In a society undergoing significant change, it is necessary to give careful thought to which groups will be perceived as authoritative organisations by the constituents of the future. The ideal form of an authoritative organisation in the new society of the future is to continue to show how it came to make such recommendations, how it reflected the opinions of interested parties in the process, and how it discloses its records with as much transparency as possible. The question now is what we must do to ensure that decision-making advances in a way that not only makes sense to the present generation, but will be easily consumed by future generations. The path that ICRP is taking to formulate the next set of General Recommendations is doing just that, in line with the key procedural values of INCLUSIVE, ACCOUNTABLE, AND TRANSPARENT.


Asunto(s)
Protección Radiológica , Humanos
5.
J Appl Microbiol ; 112(3): 464-74, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22257006

RESUMEN

AIMS: To investigate the involvement of osmoprotectant transporters in organic solvent tolerance in Escherichia coli and to construct an E. coli strain with high organic solvent tolerance. METHODS AND RESULTS: The organic solvent tolerance of ΔbetT, ΔproV, ΔproP or ΔputP single-gene knockout mutants of E. coli K-12 strain was examined. Among these mutants, the organic solvent tolerance of the ΔproV mutant remarkably increased compared with that of the parent strain. It has been known that a marR mutation confers tolerance on E. coli to organic solvents. A ΔproV and ΔmarR double-gene mutant was more tolerant to organic solvents than the ΔproV or ΔmarR single-gene mutant. The n-hexane amount accumulated in E. coli cells was examined after incubation in an n-hexane-aqueous medium two-phase system. The intracellular n-hexane level in the ΔproV and ΔmarR double-gene mutant was kept lower than those of the parent strain, ΔproV mutant and ΔmarR mutant. CONCLUSIONS: The organic solvent tolerance level in E. coli highly increased by dual disruption of proV and marR. SIGNIFICANCE AND IMPACT OF THE STUDY: This study suggests a new strategy for increasing the organic solvent tolerance level in E. coli to improve the usability of the whole-cell biocatalysts in two-phase systems employing organic solvents.


Asunto(s)
Proteínas de Escherichia coli/genética , Escherichia coli/efectos de los fármacos , Hexanos/farmacología , Proteínas de Transporte de Membrana/genética , Proteínas de Unión Periplasmáticas/genética , Proteínas Represoras/genética , Solventes/farmacología , Farmacorresistencia Bacteriana/genética , Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Técnicas de Inactivación de Genes , Genes Bacterianos , Lipoproteínas/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Mutación
6.
Kyobu Geka ; 65(8): 653-9, 2012 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-22868423

RESUMEN

Abdominal organ ischemia associated with aortic dissection is a serious problem, although its incidence is not so high. In particular, the prognosis of bowel ischemia is extremely poor, especially, in cases with the diagnosis delayed and with extensive bowel ischemia. Consequently, 1st it should be suspected, in cases with abdominal pain or distension associated with acute or chronic aortic dissection. Then, its pathology should be assessed quickly with enhanced computed tomography (CT) or ultrasound examination to clarify the mechanism of critical organ ischemia including dynamic obstruction or static obstruction of the visceral arteries. According to the mechanism of abdominal organ ischemia, the best treatment of catheter interventions such as catheter fenestration, endovascular aortic repair, and branch-stenting, or of conventional open surgery such as surgical abdominal aortic fenestration, graft replacement, and branch-bypass should be appropriately chosen without delay.


Asunto(s)
Aneurisma de la Aorta/cirugía , Disección Aórtica/cirugía , Isquemia/cirugía , Vísceras/irrigación sanguínea , Aneurisma de la Aorta/complicaciones , Humanos , Isquemia/complicaciones
7.
Endoscopy ; 43(1): 70-2, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21108178

RESUMEN

Tocilizumab is a monoclonal antibody against human interleukin-6 receptor which blocks the binding of interleukin-6 to its receptor. Tocilizumab is effective for the treatment of inflammatory disorders including rheumatoid arthritis. We report a case of multiple ulcers in the small and large intestines, which occurred during tocilizumab therapy. A 57-year-old woman started to use tocilizumab for rheumatoid arthritis. Three months later, she complained of hematochezia. Double-balloon endoscopy revealed multiple small aphthoid ulcers in the small and large intestines. One month after the woman had recovered, she was given tocilizumab again. The woman had hematochezia and abdominal pain again 2 weeks later. Colonoscopy revealed multiple round, discrete punched-out ulcers in the terminal ileum, and vast deep ulcers from the cecum to the descending colon. Bioptic histopathology and cultivation showed non-specific findings. Six weeks after discontinuation of tocilizumab, ulcers in the small and large intestine dramatically improved, leaving ulcer scars. This disease course and the results of examination made us strongly suspect that tocilizumab induced multiple ulcers in the small and large intestines. Interleukin-6 is a pleiotropic cytokine and involved in intestinal mucosal wound healing as well as in inflammatory processes. It is possible that tocilizumab inhibited tissue repair of the intestine and caused intestinal ulcers.


Asunto(s)
Anticuerpos Monoclonales/efectos adversos , Artritis Reumatoide/tratamiento farmacológico , Intestino Grueso , Intestino Delgado , Úlcera/inducido químicamente , Anticuerpos Monoclonales Humanizados , Colonoscopía , Femenino , Humanos , Interleucina-6/antagonistas & inhibidores , Enfermedades Intestinales/inducido químicamente , Persona de Mediana Edad
8.
Eur J Vasc Endovasc Surg ; 39(2): 179-86, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19962330

RESUMEN

OBJECTIVES: To clarify the incidence of spinal cord injury (SCI) after thoracic endovascular aneurysm repair (TEVAR), we investigate the intercostal/lumbar arteries that supply the Adamkiewicz artery (ICA-AKA). PATIENTS: Among 81 patients subjected to TEVAR, we retrospectively reviewed the clinical records of 50 patients (range: 57-86 (median age: 77) years, 41 males) who underwent TEVAR for part of or the whole distal descending aorta (T7 to L2) after identification of ICA-AKA by magnetic resonance angiography (MRA) or computed tomography angiography (CTA). RESULTS: The 50 patients were classified into group A: 17 patients whose patent ICA-AKA was not covered, group B: 24 patients whose ICA-AKA was covered and group C: nine patients in whom no patent ICA-AKA was identified. Only three patients in group B suffered paraplegia and of them two recovered full ambulation. The estimated incidence of permanent and transient paraplegia was 3.7% in all TEVAR patients, 6.0% when part of or the entire distal aorta was covered and 12.5% when the patent ICA-AKA was covered. The length of aortic coverage in patients with paraplegia was >300 mm. CONCLUSIONS: Paraplegia after TEVAR occurred in one of eight patients in whom the stent graft covered ICA-AKA. Long coverage of the aorta including the ICA-AKA was critical. To prevent this serious complication, identification of the ICA-AKA is crucial.


Asunto(s)
Aneurisma de la Aorta Torácica/complicaciones , Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular/métodos , Paraplejía/epidemiología , Complicaciones Posoperatorias/epidemiología , Traumatismos de la Médula Espinal/epidemiología , Médula Espinal/irrigación sanguínea , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Incidencia , Angiografía por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
9.
Science ; 280(5360): 115-8, 1998 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-9525857

RESUMEN

After the vertebrate lens is induced from head ectoderm, lens-specific genes are expressed. Transcriptional regulation of the lens-specific alphaA-crystallin gene is controlled by an enhancer element, alphaCE2. A gene encoding an alphaCE2-binding protein, L-maf(lens-specific maf), was isolated. L-maf expression is initiated in the lens placode and is restricted to lens cells. The gene product L-Maf regulates the expression of multiple genes expressed in the lens, and ectopic expression of this transcription factor converts chick embryonic ectodermal cells and cultured cells into lens fibers. Thus, vertebrate lens induction and differentiation can be triggered by the activation of L-Maf.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica , Cristalino/citología , Cristalino/embriología , Factores de Transcripción/metabolismo , Transcripción Genética , Secuencia de Aminoácidos , Animales , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico , Diferenciación Celular , Células Cultivadas , Embrión de Pollo , Cristalinas/genética , ADN Complementario , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Ectodermo , Elementos de Facilitación Genéticos , Proteínas del Ojo/genética , Factores de Unión a la G-Box , Genes Reporteros , Proteínas de Filamentos Intermediarios/genética , Cristalino/metabolismo , Factores de Transcripción Maf , Datos de Secuencia Molecular , Regiones Promotoras Genéticas , Proteínas Recombinantes de Fusión/metabolismo , Factores de Transcripción/química , Factores de Transcripción/genética , Activación Transcripcional , Transfección
10.
Endoscopy ; 41(2): 175-8, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19214900

RESUMEN

In recent years, primary gastrointestinal follicular lymphoma has been increasingly detected in the duodenum on esophagogastroduodenoscopy (EGD). Primary gastrointestinal follicular lymphomas are frequently distributed to multiple sites in the gastrointestinal tract. Therefore, investigation into the spread of follicular lymphomas in the small bowel is important in order to determine the most appropriate treatment strategy. The performance of double-balloon endoscopy (DBE) in the diagnosis of jejunoileal follicular lymphoma lesions has not been fully evaluated. We aimed to investigate the value of DBE in addition to computed tomography (CT) and (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG-PET) in the diagnosis of jejunoileal follicular lymphoma. DBE with biopsy was performed in seven patients with primary duodenal follicular lymphoma diagnosed by EGD, in order to investigate jejunoileal involvement. Jejunoileal follicular lymphoma lesions were detected by DBE in six out of the seven patients (three in the jejunum and three in the jejunum and ileum), whereas CT and (18)F-FDG-PET failed to detect the existence of these lesions. Endoscopic findings of the jejunoileal lesions revealed multiple white nodules and white villi, which were similar to those of duodenal lesions. DBE was more useful for the diagnosis of jejunoileal involvement in primary intestinal follicular lymphoma than CT and (18)F-FDG-PET. The use of DBE will become important for determining the most appropriate treatment for gastrointestinal follicular lymphoma.


Asunto(s)
Cateterismo/instrumentación , Endoscopía del Sistema Digestivo , Neoplasias Intestinales/diagnóstico , Intestino Delgado/patología , Linfoma Folicular/diagnóstico , Anciano , Estudios de Cohortes , Femenino , Humanos , Neoplasias Intestinales/terapia , Linfoma Folicular/terapia , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Resultado del Tratamiento
11.
Kyobu Geka ; 62(11): 978-81, 2009 Oct.
Artículo en Japonés | MEDLINE | ID: mdl-19827551

RESUMEN

OBJECTIVES: The aim of this study is to determine the long-term outcome of aortic valve sparing procedures for patients having connective tissue disorder. METHODS: Between 1993 and 2008, the aortic valve sparing surgery was performed in 94 patients having aortic root dilatation. Eighty patients of them (37.2 +/- 13.4 years, 50 male) had cystic medial necrosis in the aortic wall, which was confirmed the pathological examination. We reviewed these patients. Sixty percent (48/80) had Marfan syndrome, 5% (4/80) had Loeyz-Dietz syndrome, 2% (2/80) had bicuspid aortic valve, and 11% (9/80) had aortic dissection. Our reimplantation procedure has been refined as followed: with a tube graft in 41, a tube graft with creation of neo-sinuses in 11, and a Valsalva graft in 14. Fourteen patients underwent the remodeling procedure. The follow-up rate was 100% with the duration of 3.7+/- 3.4 years. RESULTS: There were no operative death but six late deaths. Seventeen (21.3%) patients required aortic valve replacement, for recurrent aortic insufficiency in 13 and infection in 4. Freedom from reoperation was 80%, 43%, and freedom from moderate or severe aortic insufficiency was 80%, 54%, at 5 and 10 years, respectively. Pathological findings of the aortic valve obtained in the reoperations showed elongation and prolapse of the aortic valve due to myxomatous degeneration and fibrous thickening caused by aortic insufficiency. CONCLUSIONS: Even in connective tissue disorders, aortic valve sparing operation is associated with acceptable long-term durability, although cusp degeneration resulting in recurrent aortic insufficiency might be progressive.


Asunto(s)
Válvula Aórtica , Enfermedades del Tejido Conjuntivo/cirugía , Adulto , Válvula Aórtica/patología , Procedimientos Quirúrgicos Cardiovasculares/métodos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Resultado del Tratamiento
12.
Clin Nephrol ; 65(3): 165-72, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16550747

RESUMEN

AIMS: Renal dysfunction affects the prognosis of patients after aortic surgery. However, the factors associated with the postoperative deterioration of renal function has not been clarified precisely. METHOD: We prospectively examined renal function in 80 patients (age: 73 +/- 7 years, 66 males) who required the elective repair of infrarenal abdominal aortic aneurysm (AAA). Serum creatinine (Scr) was measured. 24-h-creatinine clearance (Ccr) and urinary albumin excretion (UAE) were determined. Renal volume and mean renal length were calculated using the data obtained by ultrasonography. 48 patients showed normal UAE (< 30 mg/day), and 24 had microalbuminuria (30-300 mg/day) and 8 had overt proteinuria (> 300 mg/day). Scr were 0.9 +/- 0.4, 1.0 +/- 0.3 and 2.1 +/- 1.3 mg/dl, respectively. RESULTS: On Day 5 after surgery, 12 patients (15%) showed deterioration of renal function as defined either by an increase in Scr (> or = 0.5 mg/dl) or by a decrease in Ccr > or =20%). The acute deterioration of renal function was related to mean renal volume, mean renal length, duration of operation and the use of antibiotics. At Month 12 after surgery, Scr increased in the overt proteinuria group. The deterioration of renal function at Month 12 was found in 8 patients (10%) with microalbuminuria or overt proteinuria, and related to preoperative Ccr, UAE, mean renal volume, mean renal length, smoking status and blood pressure. CONCLUSION: We conclude that the deterioration of renal function occurred in considerable number of patients with AAA after elective operation on acute and chronic phase, although the development of end-stage renal failure is rare. Factors related to the acute and late deterioration appears to be different. UAE and renal size should be measured, even if Scr is in normal range at preoperative observation.


Asunto(s)
Albuminuria/etiología , Aneurisma de la Aorta Abdominal/cirugía , Creatinina/orina , Procedimientos Quirúrgicos Electivos/efectos adversos , Procedimientos Quirúrgicos Vasculares/efectos adversos , Anciano , Anciano de 80 o más Años , Albuminuria/diagnóstico , Albuminuria/orina , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Estudios Prospectivos , Renografía por Radioisótopo , Índice de Severidad de la Enfermedad , Tomografía Computarizada por Rayos X
13.
J Natl Cancer Inst ; 79(5): 1143-9, 1987 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3479640

RESUMEN

Fifteen female ACI rats initially 5 weeks old were each given a diet containing 0.027-0.08% ptaquiloside [(PT) CAS: 87625-62-5], a carcinogen in bracken, throughout the 210-day experimental period. A control group of 20 female ACI rats was given basal diet without PT. Both ileal and urinary bladder tumors developed in all rats in the experimental group. The ileal tumors were multiple and mostly developed in the distal 10 cm of the ileum. These ileal tumors were identified histologically as epithelial tumors, such as adenomas and adenocarcinomas, and also as nonepithelial malignant tumors, malignant fibrous histiocytomas. The urinary bladder tumors were transitional cell carcinomas, keratinizing squamous cell carcinomas, and sarcomas. Papillomas of the urinary bladder were found in 4 rats in the control group. These results show that, like bracken diet, PT induces tumors in both the ileum and urinary bladder.


Asunto(s)
Carcinógenos , Neoplasias del Íleon/inducido químicamente , Indanos , Sesquiterpenos , Terpenos/toxicidad , Neoplasias de la Vejiga Urinaria/inducido químicamente , Animales , Peso Corporal/efectos de los fármacos , Dieta , Femenino , Hematuria/inducido químicamente , Neoplasias Hepáticas Experimentales/inducido químicamente , Ratas , Ratas Endogámicas ACI , Sarcoma Experimental/inducido químicamente
14.
Vasa ; 35(3): 198-200, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16941411

RESUMEN

In a 71-year-old man with a history of coronary artery bypassing using the left internal thoracic and gastroepiploic arteries, the first jejunal artery aneurysms were found by chance at 3D-CT performed to evaluate conditions of the grafts. He was successfully treated by transcatheter embolization using interlocking detachable coils. During a follow-up period of 5 months, the patient did well and had no sign of intestinal ischemia.


Asunto(s)
Aneurisma/terapia , Angiografía , Embolización Terapéutica , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Hallazgos Incidentales , Yeyuno/irrigación sanguínea , Arteria Mesentérica Superior/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Anciano , Aneurisma/diagnóstico por imagen , Puente de Arteria Coronaria , Humanos , Masculino , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/terapia
15.
Oncogene ; 9(9): 2549-57, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8058318

RESUMEN

Butyrolactone I is a selective inhibitor of the cyclin-dependent kinase (cdk) family. It inhibits both cdk2 and cdc2 kinase, but scarcely affects C-kinase, A-kinase, casein kinases, MAP kinase or EGF receptor-tyrosine kinase (Kitagawa et al., 1993, Oncogene, 8, 2425-2432). We studied the effects of butyrolactone I on the cell cycle as well as on phosphorylation of retinoblastoma protein (pRB). Butyrolactone I inhibited phosphorylation of pRB catalyzed by cyclin A-cdk2 produced by baculovirus in vitro. Furthermore, it inhibited phosphorylation of pRB and cell cycle progression from G1 to S phase in WI38 cell cultures. WI38 cells arrested at the G0 phase by serum starvation progressed in the cell cycle after serum stimulation. pRB was phosphorylated after 10 h serum stimulation. Incorporation of [3H]thymidine into the cells began to increase after 16 h serum stimulation. These processes were inhibited by butyrolactone I. Flow cytometric analysis showed that exposure to butyrolactone I inhibited progression of the cell cycle from G1 to S phase. These data suggested that initiation of DNA synthesis was inhibited by butyrolactone I and that the cell cycle was arrested in the G1 phase. Butyrolactone I also inhibited H1 histone phosphorylation in human WI38 cells and their G2/M progression. tsFT210 cells, a temperature-sensitive cdc2 mutant cell line, were synchronized at G2/M at a nonpermissive temperature, butyrolactone I inhibited the cell cycle progression of these cells at G2/M at the permissive temperature. Thus butyrolactone I, a cyclin-dependent kinase family inhibitor, which prevented the phosphorylations of the cell cycle-regulating proteins pRB and H1 histone, inhibited the cell cycle at G1/S and G2/M, respectively. These results suggest that the phosphorylations of pRB and H1 histone may play crucial roles in G1/S and G2/M progression, respectively, although it is possible that phosphorylations of other proteins by cdks are involved in G1/S and G2/M progression.


Asunto(s)
4-Butirolactona/análogos & derivados , Inhibidores de Proteínas Quinasas , Proteína de Retinoblastoma/metabolismo , 4-Butirolactona/farmacología , Ciclo Celular/efectos de los fármacos , Línea Celular , Histonas/metabolismo , Humanos , Fosforilación , Timidina/metabolismo
16.
Oncogene ; 8(9): 2425-32, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8395680

RESUMEN

We screened cdc2 kinase inhibitors from cultured mediums of micro organisms using purified mouse cyclin B-cdc2 kinase and a specific substrate peptide for cdc2 kinase. A selective inhibitor of cdc2 kinase was isolated from the cultured medium of Aspergillus species F-25799, and identified as butyrolactone I. Butyrolactone I inhibited cdc2 and cdk2 kinases but it had little effect on mitogen-activated protein kinase, protein kinase C, cyclic-AMP dependent kinase, casein kinase II, casein kinase I or epidermal growth factor-receptor tyrosine kinase. Its inhibitory effect was found to be due to competition with ATP. Butyrolactone I selectively inhibited the H1 histone phosphorylation in nuclear extracts. It also inhibited the phosphorylation of the product of retinoblastoma susceptibility gene in nuclear extracts and intact cells. Thus butyrolactone I should be very useful for elucidating the function of cdc2 and cdk2 kinases in cell cycle regulation.


Asunto(s)
4-Butirolactona/análogos & derivados , Proteína Quinasa CDC2/antagonistas & inhibidores , Quinasas CDC2-CDC28 , Quinasas Ciclina-Dependientes , Inhibidores de Proteínas Quinasas , Proteínas Serina-Treonina Quinasas , 4-Butirolactona/farmacología , Secuencia de Aminoácidos , Aspergillus/química , Proteínas Quinasas Dependientes de Calcio-Calmodulina , Quinasa 2 Dependiente de la Ciclina , Histonas/metabolismo , Técnicas In Vitro , Cinética , Datos de Secuencia Molecular , Proteínas Nucleares/metabolismo , Protamina Quinasa/antagonistas & inhibidores , Proteína Quinasa C/antagonistas & inhibidores , Proteína de Retinoblastoma/metabolismo , Especificidad por Sustrato
17.
Oncogene ; 10(9): 1691-8, 1995 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-7753545

RESUMEN

It has been postulated that the product (pRB) of the retinoblastoma gene dissociates from the E2F-pRB complex upon phosphorylation by cyclin-dependent kinase(s) (cdk). However, there is no direct evident for the regulation of formation of the E2F-pRB complex via phosphorylation by purified cdk. Therefore, we investigated the regulation of formation of this complex by phosphorylation using pRB and purified cyclin A-cdk2, cyclin E-cdk2 or cyclin D1-cdk4. Purified pRB was incubated with nuclear extracts prepared from pRB-defective cells and then subjected to gel mobility shift assays. We confirmed that unphosphorylated pRB associated with various types of E2F but pRB has been phosphorylated by cyclin A-cdk2 did not. We found that E2F-pRB complexes were disrupted as a consequence of phosphorylation by cyclin A-cdk2, and the levels of the free forms of E2Fs increased. We also found that not only the E2F-pRB complexes but also the E2F-p107 complexes were disrupted upon phosphorylation by cyclin A-cdk2. Furthermore, E2F-pRB complexes were disrupted through phosphorylation by cyclin D1-cdk4 and cyclin E-cdk2, as well as by cyclin A-cdk2. These results clearly demonstrate that the phosphorylation of pRB and p107 by cdks regulates the formation of complexes between E2F and pRB or p107.


Asunto(s)
Proteínas Portadoras , Proteínas de Ciclo Celular , Quinasas Ciclina-Dependientes/metabolismo , Proteínas Nucleares/metabolismo , Proteína de Retinoblastoma/metabolismo , Factores de Transcripción/metabolismo , Secuencia de Bases , Línea Celular , Cartilla de ADN/química , Proteínas de Unión al ADN/metabolismo , Factores de Transcripción E2F , Humanos , Técnicas In Vitro , Sustancias Macromoleculares , Datos de Secuencia Molecular , Fosforilación , Proteína 1 de Unión a Retinoblastoma , Proteína p107 Similar a la del Retinoblastoma , Factor de Transcripción DP1
18.
Oncogene ; 7(6): 1067-74, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1594240

RESUMEN

The growth-suppressive activity of the retinoblastoma (RB) protein is suggested to be regulated by phosphorylation. In studies on the kinase that phosphorylates the RB proteins, we have previously found that RB proteins can be phosphorylated by purified cdc2 kinase. In this study, we noted that RB proteins immunoprecipitated from human cell lysates are weakly phosphorylated in the absence of purified cdc2 kinase. Immunoblot analysis showed the presence of p34cdc2 in the immunoprecipitates with anti-RB monoclonal antibody. In addition, the coprecipitated kinase was found to have the same substrate specificity as cdc2 kinase. The associated kinase activity was particularly high in cells arrested in G1/S and S phase by aphidicolin. Furthermore, RB proteins were shown to be phosphorylated in nuclear extracts by some endogenous cdc2-like kinase(s). These results suggest that cdc2-like kinase is the main kinase for phosphorylation of RB proteins in vivo.


Asunto(s)
Proteína Quinasa CDC2/metabolismo , Proteína de Retinoblastoma/metabolismo , Secuencia de Aminoácidos , Animales , Afidicolina/farmacología , Ciclo Celular , Línea Celular Transformada , Núcleo Celular/metabolismo , Neoplasias del Colon , Células HeLa , Humanos , Leucemia , Neoplasias Mamarias Experimentales , Ratones , Datos de Secuencia Molecular , Neuroblastoma , Péptidos/síntesis química , Fosforilación , Especificidad por Sustrato
19.
Biochim Biophys Acta ; 618(3): 431-8, 1980 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-7397207

RESUMEN

Molecular species of rat liver choline glycerophospholipids were investigated at various stages of development by a gas chromatograph-mass spectrometer system. They were composed mainly by 1,2-diacyglycerophosphocholine and changed with development particularly during the perinatal period.. In the prenatal period, the major species were '32 : 0' (mainly 16 : 0/16 : 0, dipalmitoyl species), '34 : 0' (mainly 16 : 0/18 : 0, palmitoystearoyl speciesY, '34 : 1' (mainly 16 : 0/18 : 1, palmitoyloleoyl species) and '34 : 2' (mainly 16 : 0/18 : 2, palmitoyllinoleoyl speciesY and '32 : 0' decreased rapidly and '34 : 1' increased as the stage proceeded. After birth, however, polyunsaturated species such as '34 : 4' and '38 : 4-6' increased rapidly in contrast to the decrease of '32 : 1, 34 : 1, 36 : 1, and 34 : 0'. Moderate changes were observed in these species during subsequent development.


Asunto(s)
Hígado/metabolismo , Fosfatidilcolinas/metabolismo , Animales , Cromatografía de Gases , Ácidos Grasos/análisis , Femenino , Cromatografía de Gases y Espectrometría de Masas , Hígado/embriología , Hígado/crecimiento & desarrollo , Fosfatidilcolinas/análisis , Ratas
20.
Biochim Biophys Acta ; 574(1): 57-63, 1979 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-476137

RESUMEN

The chronological changes in molecular species of choline glycerophospholipids were studied for cerebra of 17-, 19- and 21-day-old rat fetuses, and 3-, 6-, 12-, 24- and 90-day-old rats. The molecular species found by gas chromatography-mass spectrometry and selected ion retrieval technique were phosphatidylcholines of '30 : 0, 32 : 0, 32 : 1, 34 : 0, 34 : 1, 34 : 2, 36 : 0, 36 : 1, 36 : 2, 36 : 3, and 36 : 4' where the larger number indicates the sum of chain lengths on positions C-1 and C-2; the smaller number is the total number of double bonds. Of these molecular species, '32 : 0' (mainly 16 : 0/16 : 0, dipalmitoyl glycerophosphorylcholine), '34 : 1' (mainly 16 : 0/18 : 1, palmitoyloleoyl glycerophosphorylcholine), '34 : 0' (16 : 0/18 : 0, palmitoylstearoyl glycerophosphorylcholine), '32 : 1' (mainly 16 : 0/16 : 1, palmitoylpalmitoleoyl glycerophosphorylcholine and '30 : 0' (14 : 0/16 : 0, myristoylpalmitoyl glycerophosphorylcholine) were main species. The '32 : 0' species increased to about 44% at around the 10th day and thereafter remained nearly constant. '34 : 1' and '34 : 0' decreased to about 17 and 6% at that time and then increased to about 30 and 14%, respectively. '30 : 0' increased from last stage of gestation to the 6th day and then decreased. '32 : 1' was about 16% for 17-day-old fetus and decreased grandually. '36 : 1' (18 : 0/18 : 1, stearoyloleoyl glycerophosphorylcholine) increased at the latter part of development.


Asunto(s)
Encéfalo/crecimiento & desarrollo , Fosfatidilcolinas/análisis , Envejecimiento , Animales , Animales Recién Nacidos , Encéfalo/embriología , Ácidos Grasos/análisis , Femenino , Cromatografía de Gases y Espectrometría de Masas , Ratas
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA