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1.
Colorectal Dis ; 18(1): O37-42, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26496937

RESUMEN

AIM: This study aimed to investigate the clinical utility of a prepackaged low-residue diet (PLD) compared with a restricted diet (RD) for colonoscopic bowel preparation. METHOD: A prospective randomized controlled trial was carried out with patients undergoing colonoscopy. One hundred patients were randomly assigned to PLD and RD groups. In the RD group, the patients received an information sheet containing acceptable low-residue options and instructions from the medical staff. All patients received 10 ml sodium picosulphate the day before colonoscopy and 1 l of polyethylene glycol with ascorbic acid (PEG-A) on the day of the colonoscopy. If the bowel preparation was not adequate, an additional PEG-A solution was given. The primary outcome was the efficacy of colonic cleansing as rated by the Boston Bowel Preparation Scale (BBPS). The additional amount of PEG-A solution, adenoma detection rate and patient tolerance were assessed as secondary outcomes. RESULTS: The BBPS score in the PLD group was 7.3 ± 1.7 compared with 6.5 ± 1.7 in the RD group. The quality of bowel preparation was significantly better in the PLD group (P < 0.05). The mean amount of additional PEG-A solution in the PLD group was smaller than in the RD group (293.8 ± 474.8 vs 444.1 ± 625.0 ml), but there was no statistical difference between the two groups. Adenoma detection rates and patient tolerance were similar in the two groups. CONCLUSION: Prepackaged low-residue diets PLD is superior to RD for bowel preparation for colonoscopy.


Asunto(s)
Adenoma/diagnóstico , Catárticos/uso terapéutico , Colonoscopía/métodos , Neoplasias Colorrectales/diagnóstico , Dieta/métodos , Cuidados Preoperatorios/métodos , Anciano , Ácido Ascórbico/uso terapéutico , Citratos/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Compuestos Organometálicos/uso terapéutico , Picolinas/uso terapéutico , Polietilenglicoles/uso terapéutico
3.
Int J Pharm ; 382(1-2): 80-7, 2009 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-19686825

RESUMEN

The aim of this study was to design a new orally disintegrating tablet (ODT) that has high tablet hardness and a fast oral disintegration rate using a new preparation method. To obtain rapid disintegration granules (RDGs), a saccharide, such as trehalose, mannitol, or lactose, was spray-coated with a suspension of corn starch using a fluidized-bed granulator (suspension method). As an additional disintegrant, crospovidone, light anhydrous silicic acid, or hydroxypropyl starch was also included in the suspension. The RDGs obtained possessed extremely large surface areas, narrow particle size distribution, and numerous micro-pores. When tabletting these RDGs, it was found that the RDGs increased tablet hardness by decreasing plastic deformation and increasing the contact frequency between granules. In all tablets, a linear relationship was observed between tablet hardness and oral disintegration time. From each linear correlation line, a slope (D/H value) and an intercept (D/H(0) value) were calculated. Tablets with small D/H and D/H(0) values could disintegrate immediately in the oral cavity regardless of the tablet hardness and were considered to be appropriate for ODTs. Therefore, these values were used as key parameters to select better ODTs. Of all the RDGs prepared in this study, mannitol spray-coated with a suspension of corn starch and crospovidone (2.5:1 w/w ratio) showed most appropriate properties for ODTs; fast in vivo oral disintegration time, and high tablet hardness. In conclusion, this simple method to prepare superior formulations for new ODTs was established by spray-coating mannitol with a suspension of appropriate disintegrants.


Asunto(s)
Excipientes/química , Manitol/química , Povidona/química , Almidón/química , Tecnología Farmacéutica/métodos , Administración Oral , Química Farmacéutica , Dureza , Cinética , Lactosa/química , Modelos Lineales , Modelos Químicos , Tamaño de la Partícula , Porosidad , Ácido Silícico/química , Solubilidad , Ácidos Esteáricos/química , Propiedades de Superficie , Comprimidos , Trehalosa/química
4.
Oncogene ; 25(20): 2885-9, 2006 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-16369488

RESUMEN

We recently reported that a germline insertion of a single nucleotide in the rat homologue of the human Birt-Hogg-Dubé gene (BHD) gives rise to dominantly inherited cancer in the Nihon rat model. In this study, we constructed transgenic Nihon rats with introduction of a wild-type Bhd gene to ascertain whether suppression of the Nihon phenotype is possible. Rescue from embryonic lethality of mutant homozygotes (Nihon/Nihon) and suppression of renal carcinogenesis in heterozygotes (Nihon/+) were both observed, defining the germline Bhd mutation in the Nihon rat as an embryonal lethal and tumor predisposing mutation. This transgenic rescue system will be useful to analyse Bhd gene function, its relation to tumorigenesis in vivo, and genetic-environmental interactions in carcinogenesis.


Asunto(s)
Carcinoma de Células Renales/genética , Modelos Animales de Enfermedad , Pérdida del Embrión/genética , Genes Letales , Neoplasias Renales/genética , Neoplasias Experimentales/genética , Proteínas/fisiología , Animales , Animales Modificados Genéticamente , Transformación Celular Neoplásica/genética , Femenino , Marcación de Gen , Mutación de Línea Germinal , Humanos , Masculino , Proteínas/genética , Ratas
5.
Vet Pathol ; 41(3): 285-7, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15133181

RESUMEN

Nodular thyroid hyperplasia was found in a 4-year-old male cynomolgus monkey (Macaca fascicularis). The monkey was clinically normal; however, necropsy revealed multiple variably sized nodules in both lobes of the thyroid gland. In contrast to the fairly uniform diameter of the lumen of follicles in the surrounding gland, the diameter of the follicular lumen within the hyperplastic nodules was highly variable and ranged from nonexistent to cystlike. Occasionally, in the larger follicles there were papillary infoldings of epithelium. The hyperplastic nodules were partially encapsulated by a fibrous capsule and showed little compression of the surrounding tissue. The follicular cells and colloid comprising the hyperplastic nodule were immunohistochemically positively stained with the antibody for thyroglobulin. Ultrastructurally, the cells forming follicles had numerous microvilli along the luminal surface, and lysosomal bodies and dilated rough endoplasmic reticulum in the cytoplasm. All these morphologic findings are consistent with nodular thyroid hyperplasia, which is rare in nonhuman primates.


Asunto(s)
Macaca fascicularis , Enfermedades de los Monos/patología , Glándula Tiroides/ultraestructura , Nódulo Tiroideo/veterinaria , Animales , Anticuerpos/inmunología , Inmunohistoquímica , Masculino , Microscopía Electrónica , Tiroglobulina/inmunología , Nódulo Tiroideo/patología
6.
Jpn J Cancer Res ; 92(11): 1147-9, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11714437

RESUMEN

A novel rat model of hereditary renal cell carcinoma (RC) was found in a rat colony of the Sprague-Dawley (SD) strain in Japan, and named the "Nihon" rat in 2000. This study was designed to map the RC susceptibility gene in the Nihon rat using 113 backcross animals. Our present data clearly show that the Nihon gene is genetically linked to interleukin-3 (IL3) gene (chi(2) = 93.6, Lod score = 25.16), lethal (2) giant larvae (LLGL1) locus (chi(2) = 109.0, Lod score = 31.56) and myosin heavy chain, embryonic skeletal muscle (MYHSE) gene (chi(2) = 90.6, Lod score = 23.87), which are located on the distal part of rat chromosome 10. The order of the genes is the Eker (Tsc2) gene (located on the proximal part of rat chromosome 10; human chromosome 16p 13.3)--21.3 cM--IL3 gene (human 5q23-31)--4.4 cM--Nihon gene--0.9 cM--LLGL1 locus (human 17p11.2)--4.4 cM--MYHSE gene (human 17p13.1). We also detected loss of the wild-type allele at the MYHSE locus, fitting Knudson's "two hit" model. Thus, the Nihon rat should have a mutation of a novel tumor suppressor gene related to renal carcinogenesis.


Asunto(s)
Mapeo Cromosómico , Cromosomas/genética , Predisposición Genética a la Enfermedad , Neoplasias Renales/genética , Animales , Cruzamientos Genéticos , Femenino , Orden Génico/genética , Humanos , Escala de Lod , Masculino , Reacción en Cadena de la Polimerasa , Ratas , Ratas Sprague-Dawley
7.
Toxicol Pathol ; 29(4): 458-66, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11560251

RESUMEN

To evaluate the transgenic mouse carrying a human prototype c-Ha-ras gene (rasH2 mouse) as a model for 26-week carcinogenicity tests, Di(2-ethylhexyl)phthalate (DEHP), a peroxisome proliferator, was administered to 15 rasH2 mice/sex/group at concentrations of 1,500, 3,000 or 6,000 ppm, and to 15 wild-type (non-Tg) mice/sex/group at a concentration of 6,000 ppm in their diets for 26 weeks. Survival rates and food consumption in the groups treated with DEHP and in the control group were similar. Body weight gain in rasH2 and non-Tg mice at 6,000 ppm in the terminal week decreased about 10% as compared to the control group. Common findings related to treatment with DEHP in rasH2 and non-Tg mice included hypertrophy with coarse granules and deposit of pigment in the liver, hydronephrosis and tubular regeneration in the kidney, focal atrophy in the testis, and increased eosinophilic body in the nasal cavity. Hepatocellular adenoma was induced by treatment with DEHP, and was confined to male rasH2; mice the incidence being 7%(1/15), 13%(2/15), and 27%(4/15) in the 1,500-, 3,000-, and 6,000-ppm group, respectively. Point mutation was not detected in codon 12 and 61 of human c-Ha-ras transgene upon DNA analyses on frozen samples taken from these hepatocellular adenomas. From the results obtained in this 26-week carcinogenicity study, it is concluded that DEHP is a hepato-carcinogen for transgenic mouse carrying a human prototype c-Ha-ras gene.


Asunto(s)
Adenoma de Células Hepáticas/genética , Dietilhexil Ftalato/toxicidad , Genes ras , Neoplasias Hepáticas Experimentales/genética , Proliferadores de Peroxisomas/toxicidad , Adenoma de Células Hepáticas/inducido químicamente , Adenoma de Células Hepáticas/patología , Administración Oral , Animales , Pruebas de Carcinogenicidad/métodos , Dietilhexil Ftalato/administración & dosificación , Relación Dosis-Respuesta a Droga , Femenino , Riñón/efectos de los fármacos , Riñón/patología , Túbulos Renales/efectos de los fármacos , Túbulos Renales/patología , Hígado/efectos de los fármacos , Hígado/patología , Neoplasias Hepáticas Experimentales/inducido químicamente , Neoplasias Hepáticas Experimentales/patología , Masculino , Ratones , Ratones Transgénicos , Cavidad Nasal/efectos de los fármacos , Cavidad Nasal/patología , Proliferadores de Peroxisomas/administración & dosificación , Polimorfismo Conformacional Retorcido-Simple , Factores Sexuales , Tasa de Supervivencia , Testículo/efectos de los fármacos , Testículo/patología , Factores de Tiempo
8.
Jpn J Cancer Res ; 91(11): 1096-9, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11092972

RESUMEN

A novel rat model of hereditary renal cell carcinoma (RC) was found in a rat colony of the Sprague-Dawley strain in Japan, and named the rising "Nihon" rat. In this strain, RCs develop from early preneoplastic lesions, which begin to appear at 4 weeks of age, forming adenomas by the age of 16 weeks. The RCs are predominantly of clear cell type. Southern blot, northern blot and SSCP analyses revealed no change in the Tsc1, Tsc2, VHL, and c-Met genes. Thus, the Nihon rat should be a valuable experimental model for understanding renal carcinogenesis, especially clear cell type, which is common among human RCs.


Asunto(s)
Carcinoma de Células Renales/genética , Neoplasias Renales/genética , Ligasas , Proteínas Supresoras de Tumor , Ubiquitina-Proteína Ligasas , Animales , Northern Blotting , Southern Blotting , Carcinoma de Células Renales/patología , Cruzamientos Genéticos , Modelos Animales de Enfermedad , Femenino , Genes Dominantes/genética , Genes Supresores de Tumor , Neoplasias Renales/patología , Masculino , Mutación , Linaje , Fenotipo , Polimorfismo Conformacional Retorcido-Simple , Proteínas/genética , Proteínas Proto-Oncogénicas c-met/genética , Ratas , Ratas Sprague-Dawley , Proteínas Represoras/genética , Proteína 1 del Complejo de la Esclerosis Tuberosa , Proteína 2 del Complejo de la Esclerosis Tuberosa , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau
9.
Eur J Pharm Sci ; 11(1): 81-8, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10913756

RESUMEN

Crystals of nilvadipine monohydrate were obtained from aqueous acetonitrile solution and characterized by powder and single crystal X-ray crystallography and thermal analysis. Water molecules of crystallization exist in nilvadipine monohydrate crystals in a molar ratio of 1:1 (drug-to-water) and were fixed by three hydrogen bonds with two carbonyl groups of the methyl and isopropyl esters, respectively, and one imino group of neighboring nilvadipine molecules. The conformation of the methyl and isopropyl esters in the monohydrate crystal was the reversal of that in the anhydrate crystal due to the presence of hydrogen bonds with water in the former crystal. The monohydrate crystal was slowly converted to the dehydrate at low humidity, and the latter rapidly converted to the former at high humidity. Powder X-ray diffraction studies indicated that the dehydrate retains the original structure of the monohydrate, i.e., a layer structure stacked on the ac plane perpendicular to the b-axis The solubility of the monohydrate in water was lower than that of the dehydrate and anhydrate forms, although the initial dissolution rate of the monohydrate was faster than that of the anhydrate. The present results indicated that the conformation of 1, 4-dihydropyridine-type calcium channel antagonists such as nilvadipine is easily changed by hydrogen bonds with water molecules of crystallization, and the water molecules are mobile through the void spaces formed between the layers in crystals.


Asunto(s)
Bloqueadores de los Canales de Calcio/química , Cristalografía por Rayos X , Nifedipino/análogos & derivados , Fenómenos Químicos , Química Física , Nifedipino/química
10.
Vet Pathol ; 37(2): 186-8, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10714649

RESUMEN

An ovarian choriocarcinoma was found in a 13-year-old cynomolgus monkey (Macaca fascicularis). The tumor was accompanied by a mature teratoma in the contralateral ovary. Histologically, the choriocarcinoma was characterized by nests of cells where cytotrophoblasts occupied the periphery with syncytiotrophoblasts at the center. Immunohistochemical staining for anti-human chorionic gonadotropin was positive in the syncytiotrophoblasts. The teratoma consisted of well-differentiated epidermal cells, sebaceous glands, hair follicles, cartilage, bone, and teeth. Choriocarcinoma metastases were in multiple organs. The concomitant development of choriocarcinoma and teratoma in the ovary is a consistent finding with the human counterparts of these lesions.


Asunto(s)
Coriocarcinoma/veterinaria , Macaca fascicularis , Enfermedades de los Monos/patología , Neoplasias Primarias Múltiples/veterinaria , Neoplasias Ováricas/veterinaria , Teratoma/veterinaria , Anemia/veterinaria , Animales , Coriocarcinoma/patología , Resultado Fatal , Femenino , Inmunohistoquímica , Neoplasias Primarias Múltiples/patología , Neoplasias Ováricas/patología , Teratoma/patología , Hemorragia Uterina/veterinaria
11.
J Oral Rehabil ; 27(1): 64-9, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10632845

RESUMEN

It has been shown that a test capsule originally designed as a simple and reliable aid to evaluate masticatory ability could help to identify the characteristics of chewing loops between individuals in evaluation of masticatory movement, and detect even a slight disorder in the stomatognathic system. In this study, the Sirognathograph(R) Analysing System was used to record and analyse mandibular movement with the test capsule and seven foods. In terms of total examination of the chewing rhythm, the test capsule showed a higher SX/SY ratio of chewing cycle duration (SX: variance between individuals, SY: variance between chewing loops of each person) than those of the comparative foods, excluding chewing gum. The coefficient of variation of the test capsule in the dimensions of the chewing path was lower than those of the comparative foods. Reverse and crossover patterns in chewing gum have been frequently observed in subjects with craniomandibular disorders. Subjects with a low frequency of such patterns in chewing gum tended to have a low frequency with the test capsule as well. Those with a high frequency in chewing gum tended to show such patterns with the test capsule more frequently.


Asunto(s)
Masticación/fisiología , Adulto , Análisis de Varianza , Cápsulas , Femenino , Humanos , Masculino , Movimiento/fisiología , Valores de Referencia , Estadísticas no Paramétricas
12.
Dent Mater J ; 19(1): 50-64, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11219090

RESUMEN

This study was carried out to investigate the influences of elastic moduli of the dowel-core combination on the stress distribution in the root by the use of 2-dimensional finite element analysis. The peak stress at the dowel-cement interface was influenced strongly by a change of elastic modulus of the post (from 20,000 kg/mm2 as a hard prefabricated post to 8,000 kg/mm2 as a custom cast post) for both vertical and 45 degree oblique loading (rho > 90%). Peak dentinal stress adjacent to the luting cement layer depended only on the post material for vertical loading (rho [symbol: see text] 99%). In contrast, the post and core materials (from 8,000 kg/mm2 as cast core to 300 kg/mm2 as composite resin core) acted in cooperation on the stress magnitude for oblique loading, but the influence of the core material was stronger than that of the post (rho of core [symbol: see text] 41% and rho of post [symbol: see text] 26%). On the other hand, at the marginal region the effect of the core material contributed more than 86% to the peak stress value for both loadings, and the post material affected at most about 11% of the bending resistance.


Asunto(s)
Materiales Dentales/química , Técnica de Perno Muñón , Raíz del Diente/fisiología , Algoritmos , Análisis de Varianza , Resinas Compuestas/química , Aleaciones Dentales/química , Cementos Dentales/química , Dentina/fisiología , Elasticidad , Análisis de Elementos Finitos , Humanos , Ensayo de Materiales , Modelos Biológicos , Docilidad , Estrés Mecánico , Propiedades de Superficie
13.
J Control Release ; 60(2-3): 311-9, 1999 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-10425336

RESUMEN

PURPOSE: The purpose of this study was to define membrane controlling factors responsible for drug release from a controlled-porosity osmotic pump tablet (OPT) that utilizes a sulfobutyl ether-beta-cyclodextrin, (SBE)(7m)-beta-CD, as both a solubilizing and osmotic agent. METHOD: The OPT was spray coated with cellulose acetate solutions varying the amount and size of micronized lactose, the amount of triethyl citrate (TEC) and the composition ratio of dichlormethane to ethanol. Chlorpromazine (CLP) was used as a model drug. The release of CLP from the OPTs was studied using the Japanese Pharmacopoeia dissolution method. The membrane surface area of the OPTs were measured with multi-point analysis by the gas absorption method. RESULTS: The release rate of CLP from OPTs containing (SBE)(7m)-beta-CD increased with increasing amounts of micronized lactose and decreasing amounts of TEC and lactose particle size in the membrane. Also, the CLP release rates from the spray-coated OPTs using mixtures of varying ratios of dichlormethane to ethanol were almost identical. The membrane surface area of the OPTs following release of membrane components had a linear relationship to CLP release rates from the OPTs. CONCLUSION: The present results confirmed that the membrane controlling factors responsible for the drug release were the amount and size of micronized lactose and the amount of TEC in the membrane.


Asunto(s)
Clorpromazina/farmacocinética , Ciclodextrinas/química , Preparaciones de Acción Retardada/química , Membranas Artificiales , Ósmosis , Antipsicóticos/farmacocinética , Técnicas In Vitro , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Solubilidad , Comprimidos , Factores de Tiempo
14.
J Oral Rehabil ; 26(4): 265-73, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10232853

RESUMEN

The quality of life (QOL) in patients with cancer in the head and neck regions has become an increasingly important factor in medical treatment. We examined the effect of a prosthesis on the QOL based on the patients' own subjective evaluations. Sixty-eight head and neck cancer patients who had been treated in the Department of Prosthetic Dentistry of the Faculty of Dentistry, Kyushu University, were compared with 35 denture wearers as a control. General denture satisfaction in the control group showed a statistical correlation with eating (P<0.01, t-test; rho = 0.72, Spearman rank correlation), aesthetic satisfaction (P<0.01, rho = 0.57) and pain (P<0.01, rho = 0.51). On the other hand, for cancer patients, general denture satisfaction showed a statistical correlation with not only eating (P<0.01, rho = 0.34), aesthetic satisfaction (P<0.01, rho = 0.33) and pain (P<0.01, rho = 0.41) but also health (P<0.01, rho = 0.33) and mental well-being (P<0.01, rho = 0.41). A statistical correlation between the Denture score and the QOL score was thus observed in cancer patients (P<0.0001, rho = 0.56), while the correlation for the control group was not statistically significant. This study showed that oral prostheses for head and neck cancer patients are important factors not only for eating but also for the overall patient QOL.


Asunto(s)
Dentadura Completa/psicología , Neoplasias de Cabeza y Cuello/rehabilitación , Calidad de Vida , Adaptación Psicológica , Adulto , Anciano , Anciano de 80 o más Años , Distribución de Chi-Cuadrado , Comunicación , Ingestión de Alimentos , Estética Dental , Dolor Facial/psicología , Femenino , Estado de Salud , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Factores Sexuales , Habla , Estadísticas no Paramétricas , Encuestas y Cuestionarios
15.
Pharm Res ; 16(4): 549-54, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10227711

RESUMEN

PURPOSE: The purpose of this study was to develop a controlled-porosity osmotic pump tablet (OPT) which exhibits pH-independent release profiles for a basic drug using a sulfobutyl ether-beta-cyclodextrin, (SBE)7m-beta-CD, which acts as both a solubilizer and as an osmotic agent. METHODS: Chlorpromazine free base (CLP) was chosen as a model drug for this study. The release of CLP from osmotic pump tablets was studied in vitro. In vivo absorption of CLP from the OPT was evaluated in male beagle dogs. RESULTS: The CLP release profile from an OPT prepared from a core tablet composed of a 1:10 molar ratio of CLP to (SBE)7m-beta-CD was pH-independent, and was controlled by modulating the membrane thickness of the OPT. Another cyclodextrin, hydroxypropyl-beta-cyclodextrin (HP-beta-CD), and a sugar mixture of lactose and fructose resulted in pH-dependent release at the same molar ratio. An in vivo absorption study in dogs with an OPT containing (SBE)7m-beta-CD correlated very well with the in vitro release profiles using the Japanese Pharmacopoeia dissolution method. CONCLUSIONS: In addition to serving as a solubilizer and osmotic agent, (SBE)7m-beta-CD can also serve as the controlling agent for pH independent release of CLP from OPTs. This system successfully modified the in vivo input rate of CLP without compromising oral bioavailability.


Asunto(s)
Clorpromazina/química , Clorpromazina/farmacocinética , Ciclodextrinas/química , Ciclodextrinas/farmacocinética , Antagonistas de Dopamina/química , Antagonistas de Dopamina/farmacocinética , beta-Ciclodextrinas , 2-Hidroxipropil-beta-Ciclodextrina , Absorción , Animales , Clorpromazina/administración & dosificación , Ciclodextrinas/administración & dosificación , Preparaciones de Acción Retardada , Perros , Antagonistas de Dopamina/administración & dosificación , Diseño de Fármacos , Fructosa/administración & dosificación , Fructosa/química , Fructosa/farmacocinética , Concentración de Iones de Hidrógeno , Lactosa/administración & dosificación , Lactosa/química , Lactosa/farmacocinética , Masculino , Presión Osmótica , Solubilidad , Comprimidos
16.
J Control Release ; 58(1): 29-38, 1999 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-10021487

RESUMEN

A controlled porosity osmotic pump system for poorly water soluble drugs has been developed using sulfobutyl ether-beta-cyclodextrin sodium salt, (SBE)7m-beta-CD, which can act as both a solubilizing and an osmotic agent. The release of testosterone, a poorly water soluble drug (0.039 mg/ml at 37 degrees C), was evaluated using a new model device. The effect of (SBE)7m-beta-CD as the solubilizing and osmotic pump agent was compared with hydroxypropyl-beta-cyclodextrin (HP-beta-CD), a neutral cyclodextrin, and a sugar mixture (osmotic agent only). Testosterone release from the device was significantly faster with (SBE)7m-beta-CD than with HP-beta-CD or the sugar mixture. The solubility of testosterone in the device increased to 76.7 mg/ml through complexation with (SBE)7m-beta-CD in the imbibed water. It appears that testosterone release from the device in the presence of (SBE)7m-beta-CD was mainly due to osmotic pumping while for HP-beta-CD the major contribution appears to be due to diffusion. In the case of the sugar mixture, testosterone was poorly released, presumably due to the absence of a solubilizer. Therefore, it was concluded that (SBE)7m-beta-CD provides novel properties for the development of controlled- porosity osmotic pump tablets for poor solubility drugs.


Asunto(s)
Ciclodextrinas/química , Testosterona/administración & dosificación , beta-Ciclodextrinas , Algoritmos , Secuencia de Carbohidratos , Preparaciones de Acción Retardada , Difusión , Cinética , Membranas Artificiales , Datos de Secuencia Molecular , Presión Osmótica , Solubilidad , Comprimidos , Testosterona/química
17.
Pharm Res ; 15(10): 1562-8, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9794499

RESUMEN

PURPOSE: The purpose of this study was to develop a controlled-porosity osmotic pump tablet (OPT) for poorly water soluble drugs using a sulfobutyl ether-beta-cyclodextrin, (SBE)7m-beta-CD or Captisol, which acted as both a solubilizer and as an osmotic agent. METHODS: Prednisolone (PDL) was chosen as a model drug for this study. The release of PDL from osmotic pump devices and tablets was studied. In vivo absorption of PDL from OPT was evaluated in male beagle dogs. RESULTS: PDL release from the osmotic pump tablet with (SBE)7m-beta-CD was complete. Another cyclodextrin, hydroxypropyl-beta-cyclodextrin (HP-beta-CD), and a sugar mixture of lactose and fructose resulted in incomplete release. Although PDL release from the OPT with (SBE)7m-beta-CD and the sugar formulation displayed mainly zero-order release characteristics, the tablet utilizing HP-beta-CD showed apparent first-order release characteristics. An in vivo absorption study in dogs correlated very well with the in vitro release profiles using the Japanese Pharmacopoeia dissolution method. CONCLUSIONS: The present results confirm that (SBE)7m-gamma-CD can serve as both the solubilizer and the osmotic agent for OPT of PDL, and modify the input rate of PDL without compromising oral bioavailability.


Asunto(s)
Ciclodextrinas/administración & dosificación , Prednisolona/administración & dosificación , beta-Ciclodextrinas , Absorción , Animales , Perros , Masculino , Prednisolona/química , Prednisolona/farmacocinética , Solubilidad , Comprimidos
18.
Int J Prosthodont ; 10(1): 78-82, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9484074

RESUMEN

The occlusal curvature should be harmonized with stomatognathic function, but excessive occlusal curvatures are found in some craniomandibular disorder patients. Forty healthy subjects and 95 patients with craniomandibular disorder (50 with clicking, 25 with locking, and 20 with myofascial pain dysfunction syndrome) were evaluated to investigate the functional significance of the occlusal curvature. Anteroposterior and lateral occlusal curvature were measured using the least-square approximation of the mandibular buccal cusps in a second-order quadratic and modification of Monson's 4-inch sphere. "Clicking" and "locking" groups had significantly greater occlusal curvatures than healthy subjects. There appeared to be a relationship between occlusal curvature and craniomandibular disorders.


Asunto(s)
Trastornos Craneomandibulares/etiología , Arco Dental , Oclusión Dental , Maloclusión/complicaciones , Adolescente , Adulto , Análisis de Varianza , Estudios de Casos y Controles , Trastornos Craneomandibulares/fisiopatología , Humanos , Luxaciones Articulares/etiología , Maloclusión/fisiopatología , Modelos Biológicos , Disco de la Articulación Temporomandibular/fisiopatología , Síndrome de la Disfunción de Articulación Temporomandibular/etiología , Síndrome de la Disfunción de Articulación Temporomandibular/fisiopatología
19.
Int J Prosthodont ; 9(2): 171-8, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8639241

RESUMEN

This study was conducted to examine prevalence of craniomandibular disorders in young adults compared with that in older subjects. In addition, the relationship between various oral conditions and this dysfunction was studied. No difference was found in the incidence of craniomandibular disorders between the groups. Classification according to the Helkimo index showed significant difference in complaints of craniomandibular disorders symptoms between the groups. Most of the older patients did not complain of mild disorders. The results suggest that conditions such as the number of teeth, presence or absence of dentures, and the type of denture worn are not important factors in the pathogenesis of craniomandibular disorders.


Asunto(s)
Trastornos Craneomandibulares/epidemiología , Trastornos Craneomandibulares/etiología , Adulto , Distribución por Edad , Factores de Edad , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Fuerza de la Mordida , Dentaduras/efectos adversos , Dolor Facial/etiología , Femenino , Humanos , Incidencia , Arcada Parcialmente Edéntula/complicaciones , Masculino , Prevalencia , Índice de Severidad de la Enfermedad , Distribución por Sexo , Estadísticas no Paramétricas , Trastornos de la Articulación Temporomandibular/epidemiología , Trastornos de la Articulación Temporomandibular/etiología
20.
Pharm Res ; 13(2): 256-64, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8932446

RESUMEN

PURPOSE: The objective of this work was to determine the role that charge might play in the interaction of charged and uncharged drugs with neutral (2-hydroxypropyl-beta-cyclodextrin, HP-beta-CD) and anionically charged (SBE7-beta-CD) modified beta-cyclodextrins. SBE7-beta-CD is a sulfobutyl ether, sodium salt, derivative variably substituted on the 2-, 3- and the 6-positions of beta-cyclodextrin. The number seven refers to the average degree of substitution. METHODS: The binding of the acidic drugs, indomethacin, naproxen and warfarin and the basic drugs, papaverine, thiabendazole, miconazole and cinnarizine with the two cyclodextrins was determined at 25 degrees C as a function of pH and cyclodextrin concentration by the phase-solubility method. RESULTS: Except for miconazole and cinnarizine (Ap-type diagrams), all other materials studied displayed AL-type diagrams. By comparing the binding constants of both the charged and uncharged forms of the same drugs to both HP-beta-CD and SBE7-beta-CD, the following conclusions could be drawn. The binding constants for the neutral forms of the drugs were always greater with SBE7-beta-CD than with HP-beta-CD. For the anionic agents, the binding constants between SBE7-beta-CD and HP-beta-CD were similar while the binding constants for the cationic agents with SBE7-beta-CD were superior to those of HP-beta-CD, especially when compared with the neutral form of the same drug. CONCLUSIONS: A clear charge effect on complexation, attraction in the case of cationic drugs and perhaps inhibition in the case of anionic drugs, was seen with the SBE7-beta-CD.


Asunto(s)
Ciclodextrinas/química , beta-Ciclodextrinas , 2-Hidroxipropil-beta-Ciclodextrina , Aniones , Secuencia de Carbohidratos , Fenómenos Químicos , Química Física , Ciclodextrinas/metabolismo , Interacciones Farmacológicas , Cinética , Datos de Secuencia Molecular , Solubilidad
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