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1.
Ann Trop Med Parasitol ; 104(5): 383-90, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20819306

RESUMEN

After two cases of amoebic colitis were detected at an institution for the mentally retarded in the Yamagata prefecture of Japan, the prevalence and epidemiology of Entamoeba histolytica infection at the institution were investigated. When the 76 residents with mental retardation were checked by serology and stool examinations, 40 (53%) showed evidence of infection with E. histolytica (i.e. E. histolytica-specific antibodies in their serum, Entamoeba cysts in their stools, and/or E. histolytica-specific antigens in their stools). The cysts were all assumed to be those of E. histolytica since all nine of the 18 cyst-positive stool samples investigated using a PCR (that distinguishes E. histolytica from E. dispar) were found positive for this species. The E. histolytica found in the institution in Yamagata appears to have been brought into the institution, from a similar institution in Kanagawa prefecture, by a mentally retarded individual who relocated from Kanagawa to Yamagata. Isolates of E. histolytica recovered during an outbreak in the institution in Kanagawa appear genotypically identical to the genotyped isolates collected in the outbreak investigated in the present study. The 40 infected individuals in Yamagata were each treated for 10 days with metronidazole or diloxanide furoate. The residents and staff of the institution were encouraged to wash their hands more frequently and more thoroughly, and the staff were asked to clip residents' fingernails and to improve the cleanliness/sterilization of the surfaces in the institution that were most likely to be contaminated with E. histolytica (lavatories, handrails, doors, doorknobs, washrooms, clothing etc). In the last 5 years of follow-up since the instigation of these and other infection-control measures, and the last treatments, no cases of E. histolytica infection have been found in the institution. This encouraging result offers hope and guidance to those attempting to control outbreaks of E. histolytica infection in other institutions.


Asunto(s)
Entamoeba histolytica/aislamiento & purificación , Entamebiasis/epidemiología , Discapacidad Intelectual/parasitología , Adulto , Anticuerpos Antiprotozoarios/sangre , Antígenos de Protozoos/análisis , ADN Protozoario/análisis , Entamoeba histolytica/inmunología , Entamebiasis/parasitología , Entamebiasis/prevención & control , Heces/parasitología , Femenino , Humanos , Institucionalización , Japón/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Adulto Joven
2.
Opt Express ; 16(25): 20706-23, 2008 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-19065210

RESUMEN

In self-assembled multilayer arrays of micrometer-sized spheres that include small amounts of fluorescent particles, unique six-dot-triangular and seven-dot-hexagonal patterns have been known to appear in the fluorescence microscopic images. Although it has been suggested that these two types of patterns correspond to local domain structures, i.e., face centered cubic (fcc) or hexagonal closed packed (hcp), no conclusive evidence has been provided to support this claim. In this study, we systematically investigated the relationship between the propagation patterns and the arrangement of the particles. Through a cross-check between an experiment using well-defined clusters fabricated by a micromanipulation technique and a rigorous calculation based on the expansion of vector spherical harmonics, we confirmed that the six-dot-triangular and seven-dot-hexagonal patterns correspond to the fcc and hcp domains, respectively. Further, we also found that the propagation patterns depend on the size of the clusters. As a result of a quantitative discussion on the light propagation in clusters with various sizes, it was clarified that a sufficient domain size is necessary for the appearance of clear triangular or hexagonal patterns.


Asunto(s)
Colorantes Fluorescentes/química , Microscopía Fluorescente/métodos , Modelos Teóricos , Simulación por Computador , Luz , Microesferas , Fotones , Dispersión de Radiación
3.
Kyobu Geka ; 59(12): 1123-6, 2006 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-17094555

RESUMEN

A 62-year-old male who had had the left femoral neck fracture due to a traffic accident 1 year earlier was admitted to our hospital because of abdominal pain. He was diagnosed with a left traumatic diaphragmatic hernia due to the previous traffic accident; his condition was also complicated by shock because the mediastinum was compressed by his severely dilated stomach. We performed an emergent operation. A thoracotomy revealed a large defect, about 5 cm in size, at the central tendon of the left diaphragm and a severely dilated stomach in the left thoracic cavity. The ruptured diaphragm was closed directly after reduction of the stomach.


Asunto(s)
Hernia Diafragmática Traumática/etiología , Choque/etiología , Traumatismos Torácicos/complicaciones , Heridas no Penetrantes/complicaciones , Accidentes de Tránsito , Hernia Diafragmática Traumática/cirugía , Humanos , Masculino , Persona de Mediana Edad , Traumatismos Torácicos/cirugía , Heridas no Penetrantes/cirugía
4.
Gut ; 54(3): 419-25, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15710994

RESUMEN

BACKGROUND: The prognosis of hepatocellular carcinoma (HCC) is highly dependent on tumour extension and liver function. Recently, two new prognostic scoring systems-the CLIP score, developed by Italian investigators and the BCLC score, developed in Barcelona-have been widely used to assess prognosis in patients presenting with hepatocellular carcinoma. Each system has its own relative limitations. AIMS: To create a new prognostic scoring system which is simple, easy to calculate, and suitable for estimating prognosis during radical treatment of early HCC. METHODS: A total of 403 consecutive patients with HCC treated by percutaneous ablation at the Department of Gastroenterology, University of Tokyo Hospital, between 1990 and 1997 were used as the training sample to identify prognostic factors for our patients and used to develop the Tokyo score. As a testing sample, 203 independent patients who underwent hepatectomy at the Department of Hepato-Biliary-Pancreatic Surgery were studied. Prognostic factors were analysed by univariate and multivariate Cox proportional hazard regression. RESULTS: The Tokyo score consists of four factors: serum albumin, bilirubin, and size and number of tumours. Five year survival was 78.7%, 62.1%, 40.0%, 27.7%, and 14.3% for Tokyo scores 0, 1, 2, 3, and 4-6, respectively. The discriminatory ability of the Tokyo score was internally validated by bootstrap methods. The Tokyo score, CLIP score, and BCLC staging were compared by Akaike information criterion and Harrell's c index among training and testing samples. In the testing sample, the predictive ability of the Tokyo score was equal to CLIP and better than BCLC staging. CONCLUSIONS: The Tokyo score is a simple system which provides good prediction of prognosis for Japanese patients with HCC requiring radical therapy.


Asunto(s)
Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Estadificación de Neoplasias/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Bilirrubina/sangre , Biomarcadores/sangre , Carcinoma Hepatocelular/terapia , Femenino , Humanos , Neoplasias Hepáticas/terapia , Masculino , Persona de Mediana Edad , Pronóstico , Reproducibilidad de los Resultados , Albúmina Sérica/metabolismo , Índice de Severidad de la Enfermedad , Análisis de Supervivencia , Resultado del Tratamiento
5.
Int Endod J ; 37(7): 489-93, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15189439

RESUMEN

AIM: To investigate chemical changes in calcium hydroxide introduced into human root canals as a medicament using Fourier transform-(FT) Raman spectroscopy. METHODOLOGY: Ten necrotic maxillary anterior teeth were selected in 10 patients. The teeth were divided into five treatment groups, according to the survey time. Root canal instrumentation was performed with hand instruments until the master apical file was size 40. Calcium hydroxide paste, in a 1 : 1.25 mixture by weight of powder and distilled water, was introduced directly into the root canal with a lentulo-spiral filler and then condensed with a finger plugger. The access cavity was sealed with a temporary dressing. After 2 and 4 days, then 2, 4 and 6 weeks, the calcium hydroxide paste was sampled with a K-file and then analysed using FT-Raman spectroscopy. The excitation source was an Nd : YAG laser with an excitation wavelength of 1064 nm. All spectra were taken with a laser power of 200 mW, 275-1185 scans, and 4 cm(-1) resolution. The conversion of calcium hydroxide to calcium carbonate was calculated on the basis of the spectral data obtained from the mixtures of both compounds. RESULTS: The calcium hydroxide paste in the apical region showed weak bands at 1088 and 284 cm(-1), in addition to bands associated with calcium hydroxide. The weak bands, assigned to calcium carbonate, became stronger with time. Calcium carbonate content increased rapidly in the first 2 days and then tended to increase slowly. Approximately 11% of the calcium hydroxide at the apical portion of the canal was converted to calcium carbonate after 6 weeks. However, little alteration of the paste was noticed in the samples from the middle portion of the canal. CONCLUSIONS: Calcium hydroxide medicament in root canals became transformed into calcium carbonate in the apical region within 2 days. Although the transformation continued with time, approximately 90% of the calcium hydroxide remained unchanged after 6 weeks.


Asunto(s)
Carbonato de Calcio/química , Hidróxido de Calcio/química , Materiales de Obturación del Conducto Radicular/química , Irrigantes del Conducto Radicular/química , Carbonato de Calcio/análisis , Necrosis de la Pulpa Dental/terapia , Análisis de Fourier , Humanos , Espectrometría Raman/métodos
6.
Chem Biol ; 8(11): 1011-24, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11731293

RESUMEN

BACKGROUND: The secosteroid 1 alpha,25-dihydroxyvitamin D(3) (1) has a wide variety of biological activities, which makes it a promising therapeutic agent for the treatment of cancer, psoriasis and osteoporosis. Insight into the structure-activity relationships of the A-ring of 1 is still needed to assist the development of more potent and selective analogues as candidate chemotherapeutic agents, as well as to define the molecular mode of action. RESULTS: All possible A-ring stereoisomers of 5,6-trans-2-methyl-1,25-dihydroxyvitamin D(3) (6a-h) and their 20-epimers (7a-h) were designed and efficiently synthesized. The dependence of the affinities for vitamin D receptor (VDR) and vitamin D binding protein (DBP), as well as the HL-60 cell differentiation-inducing activity, upon the stereochemistry of the A-ring and at C20 in the side chain was evaluated. CONCLUSIONS: The binding affinities and potency of the 5,6-trans and 5,6-cis analogues were enhanced by a 2-methyl substituent in a certain orientation. Molecular docking studies based upon the X-ray crystal structure of VDR suggested that the axial 2-methyl group would be accommodated in a pocket surrounded by hydrophobic amino acid residues in the ligand binding domain, resulting in enhanced interaction.


Asunto(s)
Vitamina D/análogos & derivados , Vitamina D/química , Animales , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacología , Sitios de Unión , Bovinos , Diferenciación Celular/efectos de los fármacos , Células HL-60 , Humanos , Unión Proteica , Conformación Proteica , Receptores de Calcitriol/química , Receptores de Calcitriol/metabolismo , Estereoisomerismo , Relación Estructura-Actividad , Timo , Vitamina D/metabolismo , Vitamina D/farmacología , Proteína de Unión a Vitamina D/química , Proteína de Unión a Vitamina D/metabolismo
7.
Nihon Kokyuki Gakkai Zasshi ; 39(9): 699-704, 2001 Sep.
Artículo en Japonés | MEDLINE | ID: mdl-11729692

RESUMEN

A 46-year-old woman had been treated with 1,600-2,000 micrograms/day of beclomethasone dipropionate (BDP) and oral theophylline on the basis of a diagnosis of bronchial asthma in 1993. Eosinophilic pneumonia was diagnosed in June 1999, and she was then treated with 40 mg/day of oral prednisolone (PSL), which was gradually tapered off, and then stopped in October 1999. She was referred to our hospital because acid-fast bacilli were found in the sputum on January 18, 2000. Her chest radiographs and CT scans showed partial atelectasis of the right upper lobe, and fiberoptic bronchoscopy revealed bronchial inflammatory changes and whitish mucosal nodular lesions in the walls of the lower trachea, the right main bronchus and the orifice of the right upper lobe bronchus. She was found to have endobronchial tuberculosis. Anti-tuberculosis treatment with isoniazid, rifampicin, streptomycin and pyrazinamide was started. Serum levels of interferon-gamma were markedly elevated on admission. Asthma symptoms improved for a period of one month after the beginning of anti-tuberculosis treatment, despite the termination of inhaled corticosteroid. However, as the tuberculosis improved, the frequency and severity of the asthma increased and so corticosteroid inhalation was started again. Four months after administration of the anti-tuberculosis drug, fiberoptic bronchoscopy revealed that the endobronchial lesions had improved without any stenosis or constrictive changes. It was speculated that high doses of inhaled corticosteroid may have the potential to cause endobronchial tuberculosis whilst, ironically, at the same time preventing bronchial stenosis by endobronchial tuberculosis. This is an interesting case in which the asthma symptoms first decreased during the acute phase of endobronchial tuberculosis and then increased again after the tuberculosis improved.


Asunto(s)
Corticoesteroides/administración & dosificación , Asma/complicaciones , Enfermedades Bronquiales/etiología , Tuberculosis Pulmonar/etiología , Administración por Inhalación , Asma/tratamiento farmacológico , Femenino , Humanos , Persona de Mediana Edad
8.
J Org Chem ; 66(26): 8760-71, 2001 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-11749604

RESUMEN

Novel 2alpha-substituted 1alpha,25-dihydroxyvitamin D(3) analogues with 2alpha-alkyl and 2alpha-hydroxyalkyl groups were systematically synthesized from D-xylose. Their conformation on binding to the ligand binding domain (LBD) of the vitamin D receptor was analyzed. It has been found that the 2alpha-hydroxypropyl group best fits the cavity of the LBD, and the binding activity is three times higher than that for the natural hormone.


Asunto(s)
Calcitriol/análogos & derivados , Calcitriol/síntesis química , Receptores de Calcitriol/química , Calcitriol/química , Cristalografía por Rayos X , Ligandos , Modelos Moleculares
9.
J Cell Biochem ; 82(4): 599-609, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11500938

RESUMEN

In a recent study, we investigated the metabolism of 1alpha,25-dihydroxy-20-epi-vitamin D3 (1alpha,25(OH)2-20-epi-D3), a potent synthetic vitamin D3 analog in the isolated perfused rat kidney and proposed that the enhanced biological activity of 1alpha,25(OH)2-20-epi-D3 is in part due to its metabolism into stable bioactive intermediary metabolites derived via the C-24 oxidation pathway (Siu-Caldera et al. [1999] J. Steroid. Biochem. Mol. Biol. 71:111-121). It is now well established that 1alpha,25(OH)2D3 and its analogs are metabolized in target tissues not only via the C-24 oxidation pathway but also via the C-3 epimerization pathway. As the perfused rat kidney does not express the C-3 epimerization pathway, we could not identify other possible bioactive metabolites of 1alpha,25(OH)2-20-epi-D3 such as 1alpha,25(OH)2-20-epi-3-epi-D3, derived via the C-3 epimerization pathway. Therefore, we studied the metabolism of 1alpha,25(OH)2-20-epi-D3 in rat osteosarcoma cells (UMR 106) which express both the C-24 oxidation and the C-3 epimerization pathways. Our results indicate that 1alpha,25(OH)2-20-epi-D3 is metabolized in UMR 106 cells into several metabolites which included not only the previously known metabolites of the C-24 oxidation pathway but also three new metabolites which were labeled as metabolites X, Y1, and Y2. Metabolite X was unequivocally identified as 1alpha,25(OH)2-20-epi-3-epi-D3. Even though definite structure identification of the metabolites, Y1 and Y2 was not achieved in our present study, we determined that the metabolite Y1 is produced from 1alpha,25(OH)2-20-epi-D3 and the metabolite Y2 is produced from 1alpha,25(OH)2-20-epi-3-epi-D3. We also noted the production of both 1alpha,25(OH)2-20-epi-3-epi-D3 and the two metabolites Y1 and Y2 in different rat osteosarcoma cells (ROS 17/2.8) which express only the C-3 epimerization pathway but not the C-24 oxidation pathway. Furthermore, we investigated the metabolism of 1alpha,25(OH)2-20-epi-D3 in the isolated perfused rat kidney in an earlier study. The results of this study indicated that the rat kidney unlike rat osteosarcoma cells did not produce either 1alpha,25(OH)2-20-epi-3-epi-D3 or the metabolites Y1 and Y2. Thus, it appears that the metabolites Y1 and Y2, like 1alpha,25(OH)2-20-epi-3-epi-D3, are produced only in specific tissues. Preliminary biological activity of each new metabolite is assessed by measuring its ability to generate VDR-mediated gene transcription. 1alpha,25(OH)2-20-epi-3-epi-D3 was found to be almost equipotent to 1alpha,25(OH)2-20-epi-D3 while the metabolites, Y1 and Y2 were found to be less active. The metabolite Y1 when compared to the metabolite Y2 has higher biological activity and its potency is almost equal to 1alpha,25(OH)2D3. In summary, we report for the first time tissue specific metabolism of 1alpha,25(OH)2-20-epi-D3 into several bioactive metabolites which are derived not only via the previously established C-24 oxidation and C-3 epimerization pathways but also via a new pathway. (c) 2001 Wiley-Liss, Inc.


Asunto(s)
Calcitriol/metabolismo , Animales , Calcitriol/farmacología , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Genes Reporteros , Modelos Químicos , Osteosarcoma , Oxidación-Reducción , Ratas , Receptores de Calcitriol/metabolismo , Activación Transcripcional , Células Tumorales Cultivadas
10.
Eur Respir J ; 17(3): 481-7, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11405529

RESUMEN

Radiation pneumonitis (RP) is the most common complication of radiotherapy for thoracic tumours. The aim of this study was to evaluate the significance of pulmonary surfactant proteins (SP)-A and SP-D as new serum markers for RP. Twenty-five patients with lung tumour, who had received radiotherapy, were studied. At the completion of radiotherapy, the presence of RP was judged by chest plain radiography and chest high resolution computed tomography (HRCT). RP findings detected on chest plain radiography were seen in only three of 12 patients in whom RP was detected by HRCT. Nevertheless, both SP-A and SP-D concentrations in sera from the patients with RP were significantly higher than those from the 13 patients without RP (p = 0.0065, p = 0.0011, respectively). As with SP-A, ratios of SP-D at the completion, compared to at the initiation (1 week post/pre ratio), were also significantly higher in patients with RP than in patients without RP. When a post/pre ratio > 1.6 was considered positive, the SP-A and SP-D assays showed an 83% and 85% specificity, respectively. In conclusion, serum assays of surfactant proteins A and D may be of diagnostic value for detection of radiation pneumonitis, even when the radiographic change is faint.


Asunto(s)
Glicoproteínas/sangre , Proteolípidos/sangre , Surfactantes Pulmonares/sangre , Neumonitis por Radiación/diagnóstico , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proteína A Asociada a Surfactante Pulmonar , Proteína D Asociada a Surfactante Pulmonar , Proteínas Asociadas a Surfactante Pulmonar , Neumonitis por Radiación/sangre , Sensibilidad y Especificidad
11.
J Gastroenterol ; 36(5): 346-9, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11388399

RESUMEN

We report a 68-year-old man with three nodules of hepatocellular carcinoma (HCC) in a cirrhotic liver; the largest nodule was 3.0cm in diameter. The nodules showed hypoattenuation on computed tomography (CT) hepatic arteriography (CTA) and hyperattenuation on CT during arterial portography (CTAP), indicating that the dominant vascularity of the HCC nodules may have been the portal vein. A biopsy specimen obtained from the nodules showed well differentiated HCC (Edmondson-Steiner grade I). The imaging findings of the nodules on both CTA and CTAP are unusual, in spite of the rather large size, so this seemed suggestive of the hemodynamic properties of relatively large nodules of well differentiated HCC.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico , Anciano , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/terapia , Arteria Hepática/diagnóstico por imagen , Humanos , Cirrosis Hepática/complicaciones , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/terapia , Masculino , Radiografía , Tomógrafos Computarizados por Rayos X
12.
Intern Med ; 40(5): 432-4, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11393418

RESUMEN

Recently, various forms of Churg-Strauss syndrome (CSS) have been reported in association with the use of leukotriene receptor antagonists. A 53-year-old woman with a 5-year history of asthma associated with chronic sinusitis presented mononeuropathy, hypereosinophilia, and positive P-ANCA in October 1999. She had been treated with pranlukast (450 mg/day) and beclomethasone dipropionate (BDP) at a dose of 1,200 microg/day which had gradually been tapered to 800 microg/day over the previous 17 months. She was found to have CSS, and 60 mg/day of prednisolone was administered instead of pranlukast, resulting in an improvement of her symptoms and eosinophilia. Later, we confirmed that serum P-ANCA had been positive before the pranlukast treatment, but CSS vasculitis had not appeared at that time. We speculated that an underlying incomplete form of CSS was being masked in this case and that the reduction of inhaled corticosteroid might have been responsible for the unmasking of CSS.


Asunto(s)
Antiasmáticos/administración & dosificación , Antiasmáticos/efectos adversos , Antiinflamatorios/administración & dosificación , Asma/tratamiento farmacológico , Beclometasona/administración & dosificación , Cromonas/efectos adversos , Síndrome de Churg-Strauss/inducido químicamente , Antagonistas de Leucotrieno/efectos adversos , Administración por Inhalación , Administración Tópica , Antiasmáticos/uso terapéutico , Antiinflamatorios/uso terapéutico , Beclometasona/uso terapéutico , Síndrome de Churg-Strauss/tratamiento farmacológico , Femenino , Glucocorticoides , Humanos , Persona de Mediana Edad
13.
Bioorg Med Chem ; 9(2): 525-35, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11249144

RESUMEN

Eight 2-methyl substituted analogues of 20-epi-22R-methyl-1alpha,25-dihydroxyvitamin D3 (5) and 20-epi-24,26,27-trihomo-22-oxa-1alpha,25-dihydroxyvitamin D3 (6: KH-1060) were convergently synthesized. Preparation of the CD-ring portions with modified side chains of 5 and 6, followed by palladium-catalyzed cross-coupling with the A-ring enyne synthons (20a-d), (3S,4S,5R)-, (3S,4R,5R)-, (3S,4S,5S)- and (3R,4R,5S)-3,5-bis[(tert-butyldimethylsilyl)oxy]-4-methyloct-1-en-7-yne, afforded two sets of four A-ring stereoisomers of 20-epi-2,22-dimethyl-1,25-dihydroxyvitamin D3 (7a-d) and 20-epi-24,26,27-trihomo-2-methyl-22-oxa-1,25-dihydroxyvitamin D3 (8a-d). The biological profiles of the hybrid analogues were assessed in terms of affinity for vitamin D receptor (VDR) and HL-60 cell differentiation-inducing activity in comparison with the natural hormone. The combined modifications of the A-ring at the 2-position and the side chain yielded analogues with high potency.


Asunto(s)
Calcitriol/farmacología , Diferenciación Celular/efectos de los fármacos , Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Unión Competitiva , Calcitriol/análogos & derivados , Calcitriol/síntesis química , Cristalografía por Rayos X , Células HL-60 , Humanos , Estructura Molecular , Unión Proteica , Receptores de Calcitriol/metabolismo , Estereoisomerismo , Relación Estructura-Actividad , Vitamina D/análogos & derivados , Vitamina D/síntesis química , Vitamina D/farmacología
14.
Steroids ; 66(3-5): 277-85, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11179735

RESUMEN

All possible A-ring diastereomers of 2-methyl-1alpha,25-dihydroxyvitamin D(3) (2) and 20-epi-2-methyl-1alpha,25-dihydroxyvitamin D(3) (3) were synthesized by palladium-catalyzed coupling reaction of A-ring 'enyne' synthons with CD-ring portions. The A-ring synthons were rationally synthesized via a novel and practical route, starting with methyl (R)-(+)- and (S)-(-)-3-hydroxy-2-methyl-propionate, in good yields. X-ray crystallographic analysis of 2alpha-methyl-1alpha,25-dihydroxyvitamin D(3) (2b) and conformational analysis of the A-ring of 2alpha-methyl-(2b) and 2beta-methyl-1alpha,25-dihydroxyvitamin D(3) (2f) were carried out, and the results are described. All A-ring diastereomers (2 and 3), thus synthesized, were biologically evaluated both in vitro and in vivo. The biologic potency was highly dependent on the stereochemistry of the A-ring substituents. In particular, 2b showed 4-fold higher vitamin D receptor [VDR] binding activity than the natural hormone, and its 20-epimer (3b) exhibited exceptionally high activity, 12-fold more potent in VDR binding, 7-fold in calcium mobilization, and 590-fold in induction of human promyelocytic leukemia (HL-60) cell differentiation as compared with the natural hormone. Further, the 20-epi-2beta-Me-1beta, 3alpha(OH)(2) isomer (3g) had significant biologic potencies compared to the natural hormone despite having 1beta-OH configuration. The transcriptional activities on human osteocalcin gene promoter, including VDRE in transfected mammalian cells, were also evaluated. Finally, there was a clear contrast between the effects of the 2-methyl group on the HL-60 cell differentiation- and apoptosis-inducing activities of 2 and 3.


Asunto(s)
Vitamina D/síntesis química , Vitamina D/farmacología , Animales , Apoptosis/efectos de los fármacos , Transporte Biológico/efectos de los fármacos , Huesos/metabolismo , Calcio/sangre , Bovinos , Diferenciación Celular/efectos de los fármacos , Cristalografía por Rayos X , Células HL-60 , Humanos , Mucosa Intestinal/metabolismo , Estructura Molecular , Osteocalcina/genética , Unión Proteica , Ratas , Receptores de Calcitriol/metabolismo , Estereoisomerismo , Activación Transcripcional/efectos de los fármacos , Células Tumorales Cultivadas , Vitamina D/análogos & derivados , Vitamina D/química
16.
Biochem Pharmacol ; 60(12): 1937-47, 2000 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-11108811

RESUMEN

1alpha,25-dihydroxyvitamin D(3) (1alpha,25(OH)(2)D(3)) has been shown to modulate not only proliferation and differentiation but also apoptosis of malignant cells, indicating that it would be useful for the treatment of hyperproliferative diseases such as cancer and psoriasis. Little information is available concerning structural motifs of the 1alpha,25(OH)(2)D(3) molecule responsible for modulation of differentiation and apoptosis. We synthesized all possible A-ring diastereomers of the 2-methyl-1alpha,25(OH)(2)D(3) and its 20-epimer and evaluated their biological activities in human promyelocytic leukemia (HL-60) cells. Surprisingly, the potent analogues could be clearly divided into two groups: (i) those bearing the 1alpha- and 3beta-hydroxyl groups on the A-ring were potent inducers of differentiation and growth inhibitors of HL-60 cells and (ii) those bearing the 1beta-hydroxyl group together with either 3alpha- or 3beta-hydroxyl groups on the A-ring were potent stimulators of apoptosis in these cells. We have clearly identified for the first time the structural motifs on the basis of the stereochemistry of both hydroxyl groups at positions 1 and 3 of the A-ring of the 1alpha,25(OH)(2)D(3) molecule responsible for the induction of differentiation and apoptosis of HL-60 cells. These findings provide useful information not only for structure-function studies of 1alpha,25(OH)(2)D(3) analogues but also for the development of therapeutic agents for the treatment of leukemia and other cancers.


Asunto(s)
Apoptosis , Diferenciación Celular/efectos de los fármacos , Vitamina D/análogos & derivados , Vitamina D/farmacología , Apoptosis/fisiología , Ciclo Celular/efectos de los fármacos , Fragmentación del ADN/efectos de los fármacos , Electroforesis en Gel de Agar , Células HL-60 , Humanos , Etiquetado Corte-Fin in Situ , Leucemia Promielocítica Aguda , Antígeno de Macrófago-1/biosíntesis , Estereoisomerismo , Relación Estructura-Actividad , Vitamina D/química
17.
J Med Chem ; 43(22): 4247-65, 2000 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-11063621

RESUMEN

All eight possible A-ring diastereomers of 2-methyl-1, 25-dihydroxyvitamin D(3) (2) and 2-methyl-20-epi-1, 25-dihydroxyvitamin D(3) (3) were convergently synthesized. The A-ring enyne synthons 19 were synthesized starting with methyl (S)-(+)- or (R)-(-)-3-hydroxy-2-methylpropionate (8). This was converted to the alcohol 14 as a 1:1 epimeric mixture in several steps. After having been separated by column chromatography, each isomer led to the requisite A-ring enyne synthons 19 again as 1:1 mixtures at C-1. Coupling of the resulting A-ring enynes 20a-h with the CD-ring portions 5a,b in the presence of a Pd catalyst afforded the 2-methyl analogues 2a-h and 3a-h in good yield. In this way, all possible A-ring diastereomers were synthesized. The synthesized analogues were biologically evaluated both in vitro and in vivo. The potency was highly dependent on the stereochemistry of each isomer. In particular, the alpha alpha beta-isomer 2g exhibited 4-fold higher potency than 1 alpha,25-dihydroxyvitamin D(3) (1) both in bovine thymus VDR binding and in elevation of rat serum calcium concentration and was twice as potent as the parent compound in HL-60 cell differentiation. Furthermore, its 20-epimer, that is, 20-epi-alpha alpha beta 3g, exhibited exceptionally high activities: 12-fold higher in VDR binding affinity, 7-fold higher in calcium mobilization, and 590-fold higher in HL-60 cell differentiation, as compared to 1 alpha,25-dihydroxyvitamin D(3) (1). Accordingly, the double modification of 2-methyl substitution and 20-epimerization resulted in unique activity profiles. Conformational analysis of the A-ring by (1)H NMR and an X-ray crystallographic analysis of the alpha alpha beta-isomer 2g are also described.


Asunto(s)
Vitamina D/análogos & derivados , Vitamina D/síntesis química , Animales , Transporte Biológico , Huesos/metabolismo , Calcio/metabolismo , Bovinos , Diferenciación Celular/efectos de los fármacos , Línea Celular , Cristalografía por Rayos X , Humanos , Mucosa Intestinal/metabolismo , Espectroscopía de Resonancia Magnética , Masculino , Conformación Molecular , Ratas , Receptores de Calcitriol/metabolismo , Estereoisomerismo , Relación Estructura-Actividad , Vitamina D/química , Vitamina D/farmacología
18.
Gan To Kagaku Ryoho ; 27(10): 1496-500, 2000 Sep.
Artículo en Japonés | MEDLINE | ID: mdl-11015992

RESUMEN

We have performed percutaneous tumor ablation (PTA) including percutaneous ethanol injection therapy (PEIT) for 90% of the patients with hepatocellular carcinoma. Until December 1998, the 793 patients received PTA, 5 years survival rate reached 39.8%. Excluding the patients with Child C whose hepatic function were extremely low, 5 years survival rate reached to the level of 41.2%. Since 5 years survival rate in stage IV-A reached 24.4%, the patients of stage IV-A may be considered to have an indication for PTA. We have confirmed the effectiveness of the local treatment including radiotherapy for advanced hepatocellular carcinoma with portal vein invasion. We are attempting to perform PTA for the extra-hepatic lesions that had no indication of other treatment. However the indication of PTA is limited by the presence of diffuse nodules, exacerbation of the hepatic function, or tumor invasion to portal vein, bile duct, inferior vena cava.


Asunto(s)
Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/cirugía , Ablación por Catéter , Etanol/administración & dosificación , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/cirugía , Carcinoma Hepatocelular/mortalidad , Humanos , Inyecciones Intralesiones , Neoplasias Hepáticas/mortalidad , Tasa de Supervivencia
19.
Org Lett ; 2(17): 2619-22, 2000 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-10990411

RESUMEN

[reaction: see text]A convenient and potentially valuable synthetic approach to the novel 2alpha-functionalized 1alpha,25-dihydroxyvitamin D3 [1alpha,25(OH)2D3] derivatives (1a-c), which are the C2-epimer of ED-71 and its analogues, has been developed. The C2alpha-modified ring A precursors (1,7-enynes 16, n = 0, 1, and 2) were constructed stereoselectively starting from D-glucose in high yield. In the synthesized 2alpha-(omega-hydroxyalkoxy)-1alpha,25(OH)2D3 derivatives, 1a and 1b showed a greater binding affinity to vitamin D receptor (VDR), up to 1.8 times that of the native hormone.


Asunto(s)
Calcitriol/análogos & derivados , Receptores de Calcitriol/metabolismo , Animales , Calcitriol/síntesis química , Calcitriol/metabolismo , Bovinos , Técnicas In Vitro , Modelos Moleculares , Conformación Molecular , Paladio , Receptores de Calcitriol/química , Estereoisomerismo , Timo/metabolismo
20.
Am J Respir Crit Care Med ; 162(3 Pt 1): 1109-14, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10988138

RESUMEN

Idiopathic pulmonary fibrosis (IPF) is a progressive, life-threatening, interstitial lung disease of unknown etiology. For optimal therapeutic management of IPF an accurate tool is required for discrimination between reversible and irreversible types of the disease. However, such noninvasive tools are few, and even with high-resolution computed tomography (HRCT), which is the most trusted method for doing so, the nature of the disease activity in IPF cannot always be accurately predicted. The aims of the present study were to assess the values of surfactant protein (SP)-A and SP-D in semiquantifying the extent of disease in IPF and in predicting deterioration in restrictive pulmonary function and survival over a follow-up period of 3-yr. SP-A and SP-D in sera were measured with enzyme-linked immunosorbent assays as previously described. Fifty-two IPF patients were studied to evaluate the association between serum SP-A and SP-D and disease extent on HRCT, deterioration in pulmonary function, and survival during 3 yr of follow-up. Both SP-A and SP-D concentrations were significantly correlated with the extent of alveolitis (a reversible change), whereas they did not correlate with the progression of fibrosis (an irreversible change). The SP-D concentration, unlike that of SP-A, was also related to the extent of parenchymal collapse and the rate of deterioration per year in pulmonary function. The concentrations of SP-A and SP-D in patients who died within 3 yr were significantly higher than in patients who were still alive after 3 yr. We propose that assays of SP-A and SP-D in sera from IPF patients are useful tools for understanding some pathologic characteristics of the disease, that SP-D may be a good predictive indicator of the rate of decline in pulmonary function, and that a combination of the assays for SP-A and SP-D may be helpful in predicting the outcome of patients with IPF.


Asunto(s)
Proteolípidos/sangre , Fibrosis Pulmonar/diagnóstico , Surfactantes Pulmonares/sangre , Anciano , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Fibrosis Pulmonar/sangre , Fibrosis Pulmonar/mortalidad , Proteína A Asociada a Surfactante Pulmonar , Proteínas Asociadas a Surfactante Pulmonar , Valores de Referencia , Fumar/efectos adversos , Tasa de Supervivencia
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