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1.
Eur J Neurol ; 28(2): 389-400, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33035386

RESUMEN

BACKGROUND AND PURPOSE: Protein tyrosine phosphatase receptor type Q (PTPRQ) was extracted from the cerebrospinal fluid (CSF) of patients with probable idiopathic normal-pressure hydrocephalus (iNPH) by proteome analysis. We aimed to assess the feasibility of using CSF PTPRQ concentrations for the additional diagnostic criterion of iNPH in Japanese and Finnish populations. METHODS: We compared PTPRQ concentrations among patients with probable iNPH and neurologically healthy individuals (normal control [NC] group), patients with normal-pressure hydrocephalus (NPH) of acquired and congenital/developmental aetiologies, patients with Alzheimer's disease and patients with Parkinson's disease in a Japanese analysis cohort. A corresponding iNPH group and NC group in a Finnish cohort was used for validation. Patients in the Finnish cohort who underwent biopsy were classified into two groups based on amyloid and/or tau deposition. We measured PTPRQ expression levels in autopsied brain specimens of iNPH patients and the NC group. RESULTS: Cerebrospinal fluid PTPRQ concentrations in the patients with NPH of idiopathic, acquired and congenital/developmental aetiologies were significantly higher than those in the NC group and those with Parkinson's disease, but iNPH showed no significant differences when compared with those in the Alzheimer's disease group. For the patients with iNPH, the area under the receiver-operating characteristic curve was 0.860 in the Japanese iNPH and 0.849 in the Finnish iNPH cohorts. Immunostaining and in situ hybridization revealed PTPRQ expression in the ependymal cells and choroid plexus. It is highly possible that the elevated PTPRQ levels in the CSF are related to ependymal dysfunction from ventricular expansion. CONCLUSIONS: Cerebrospinal fluid PTPRQ levels indicated the validity of this assay for auxiliary diagnosis of adult chronic hydrocephalus.


Asunto(s)
Enfermedad de Alzheimer , Hidrocéfalo Normotenso , Adulto , Péptidos beta-Amiloides , Biomarcadores , Humanos , Proteínas Tirosina Fosfatasas , Proteínas Tirosina Fosfatasas Clase 3 Similares a Receptores
2.
Acta Neurol Scand ; 135(2): 189-196, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26923727

RESUMEN

OBJECTIVES: The cerebrospinal fluid tap test for idiopathic normal pressure hydrocephalus (iNPH) is one of the good predictors of the shunt treatment, although this test has a low sensitivity. We aimed to identify key parameters that could be used to improve this sensitivity. MATERIALS & METHODS: During 2010-2011, we recruited and then followed 93 patients with possible iNPH for 12 months after shunt. Among them, 82 patients were finally enrolled in this study. The modified Rankin Scale, iNPH grading scale, and several quantitative measurements were evaluated at entry, after the tap test, before and after shunt. Area under the receiver-operating characteristic curves (AUCs), sensitivities, and specificities of the tap test for predicting shunt effectiveness were calculated for each measurement. They were additionally assessed after stratification by disease duration since the initial presentation of iNPH symptoms. RESULTS: The gait disturbance on the iNPH grading scale had the highest accurate scale at the tap test for predicting effectiveness 12 months after shunt: AUC 0.74, sensitivity 56.5%, specificity 91.7%. This AUC increased to 0.76, 0.91 and 0.94 in the subgroup of disease duration <24, <12, and <6 months, respectively. The sensitivity and specificity of the gait disturbance on the iNPH grading scale in the subgroup of <12 months' duration were 92.3% and 90.0%. CONCLUSIONS: The shorter period of clinical symptoms, for example, <12 months, made the tap test sufficiently accurate examination for predicting improvement 12 months after shunt surgery. The findings imply that the tap test should be applied to patients being considered for shunt surgery as soon as possible.


Asunto(s)
Derivaciones del Líquido Cefalorraquídeo/normas , Hidrocéfalo Normotenso/diagnóstico , Hidrocéfalo Normotenso/cirugía , Punción Espinal/normas , Anciano , Anciano de 80 o más Años , Derivaciones del Líquido Cefalorraquídeo/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Punción Espinal/métodos , Factores de Tiempo
3.
Eur J Neurol ; 20(2): 236-42, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22672777

RESUMEN

BACKGROUND: Cognitive impairment is difficult to improve after shunt operation in patients with idiopathic normal pressure hydrocephalus (iNPH). This study aims to identify cerebrospinal fluid (CSF) biomarkers predictive of improvement in cognitive function. METHODS: This study was conducted between January 2008 and December 2010 on consecutive, unselected admissions to our program for the treatment of patients with clinically suspected iNPH. Lumbar CSF concentrations of total tau (Tau), tau phosphorylated at threonine 181 (p-tau), soluble amyloid precursor protein (sAPP), sAPPα, sAPPß, and ß-amyloid(1-42) (Aß42) were analyzed by ELISA. RESULTS: Concentrations of p-tau, sAPP, sAPPα, and sAPPß were strong diagnostic biomarkers for distinguishing between iNPH and Alzheimer's disease (AD). sAPPα exhibited the highest accuracy in differentiating iNPH from patients with AD and normal controls, with an area under the curve value of 0.994. We examined the prognostic value of p-tau and sAPPα for cognition function after surgery. With a cutoff value of 198 ng/ml or less for sAPPα, sensitivity and specificity are 66.7% and 82.9%, respectively, whilst the Mini-Mental State Examination score at 6 months after surgery is expected to be 25 or more. CONCLUSION: Our results show that sAPPα is a suitable biomarker for the diagnosis and prognosis of iNPH.


Asunto(s)
Precursor de Proteína beta-Amiloide/líquido cefalorraquídeo , Hidrocéfalo Normotenso/líquido cefalorraquídeo , Hidrocéfalo Normotenso/diagnóstico , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/líquido cefalorraquídeo , Enfermedad de Alzheimer/diagnóstico , Péptidos beta-Amiloides/líquido cefalorraquídeo , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Biomarcadores/líquido cefalorraquídeo , Biomarcadores/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fragmentos de Péptidos/líquido cefalorraquídeo , Fragmentos de Péptidos/metabolismo , Pronóstico , Sensibilidad y Especificidad , Solubilidad , Proteínas tau/líquido cefalorraquídeo , Proteínas tau/metabolismo
4.
Clin Exp Nephrol ; 16(2): 269-78, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22127399

RESUMEN

BACKGROUND: Achieving adequate blood pressure (BP) control often requires more than one antihypertensive agent. The purpose of this study was to determine whether a fixed-dose formulation of losartan (LOS) plus hydrochlorothiazide (HCTZ) (LOS/HCTZ) is effective in achieving a greater BP lowering in patients with uncontrolled hypertension. METHODS: The study was a prospective, multicenter, observational trial exploring the antihypertensive effect of a single tablet of LOS 50 mg/HCTZ 12.5 mg. A total of 228 patients whose BP had previously been treated with more than one antihypertensive agents without having achieved BP goal below 130/80 mmHg enrolled in the study. RESULTS: A significant decrease in systolic and diastolic BP was observed in both clinic and home measurement after switching from the previous treatment to LOS/HCTZ. There was a significant decrease in both B-type natriuretic peptide (BNP) and urinary albumin creatinine (Cr) excretion ratio (ACR), especially in patients with elevated values. In contrast, there was a significant increase in serum Cr concentration in conjunction with a decrease in estimated glomerular filtration rate (eGFR). Overall serum uric acid (UA) concentration increased, whereas in patients with hyperuricemia there was a significant reduction in this value. CONCLUSION: Switching to LOS/HCTZ provides a greater reduction in clinic and home BP in patients with uncontrolled hypertension. This combination therapy may lead to cardio-, reno protection and improve UA metabolism.


Asunto(s)
Antihipertensivos/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Hidroclorotiazida/uso terapéutico , Hipertensión/tratamiento farmacológico , Losartán/uso terapéutico , Adulto , Anciano , Determinación de la Presión Sanguínea , Creatinina/orina , Combinación de Medicamentos , Femenino , Tasa de Filtración Glomerular , Humanos , Hipertensión/metabolismo , Hipertensión/fisiopatología , Hiperuricemia , Japón , Masculino , Persona de Mediana Edad , Péptido Natriurético Encefálico/sangre , Estudios Prospectivos , Resultado del Tratamiento , Ácido Úrico/sangre , Adulto Joven
5.
Acta Neurochir Suppl ; 113: 97-101, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22116432

RESUMEN

OBJECTIVES: We have previously reported that the level of leucine-rich alpha-2-glycoprotein (LRG) expression is specifically increased in cerebrospinal fluid (CSF) of idiopathic normal pressure hydrocephalus (INPH). The objective of this study is to examine the localization of LRG - the cerebral areas where it is expressed. METHOD: The histological sections of autopsied brain specimens from ten subjects, five adult cases (mean age 43.6 years; range 34-50 years) and five senile cases (mean age 76.0 years; range 67-88 years) were prepared, multistained with antibodies against human LRG, glial fibrillary acidic protein (GFAP), CD31, and aquaporin-4 (AQP4), and reviewed for the expression sites of LRG. RESULTS: Immunostains of GFAP and LRG were compared in standard brain specimens from elderly patients. The results indicated that LRG is distributed throughout the entire brain, with especially high expression in the deep cerebral cortex. In addition, the cells that express LRG showed similar morphology to astrocytes. Double staining of CD31 and LRG revealed a significant expression of LRG in the pericapillary regions. The expression was observed in resident astrocytes, as well as in the capillary vessel to which astrocytic processes grow and adhere. When age-related comparisons were made between senile and adult specimens, LRG expression increased with age. CONCLUSION: LRG expression in resident astrocytes increased with age.


Asunto(s)
Encéfalo/metabolismo , Regulación de la Expresión Génica , Glicoproteínas/metabolismo , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Acuaporina 4/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Femenino , Proteína Ácida Fibrilar de la Glía/metabolismo , Transportador de Glucosa de Tipo 5/metabolismo , Glicoproteínas/genética , Humanos , Masculino , Persona de Mediana Edad , Proteínas del Tejido Nervioso/metabolismo , Factor de Transcripción 2 de los Oligodendrocitos , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/metabolismo , ARN Mensajero/metabolismo
6.
Science ; 167(3918): 563-6, 1970 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-17781498

RESUMEN

Particle track densities up to > 3 x 10(9) per square centimeter have been measured in different samples. Rocks 17, 47, 57, and 58 have VH (Z >22) galactic cosmic ray ages of 11, 14, 28, and 13 x 10(6) years, respectively. Rock 57 has a calculated erosion rate of 10(-7) centimeter per year. Near-surface track versus depth data in rock 17 can be fit with solar flare particles that have a differential energy spectrum aE(-3); lunar samples can be used to study the history of solar activity. The uranium in the crystalline rocks occurs principally in small regions <10 to approximately 100 micrometers in size. The (low) thermoluminescence of the fines increases with depth in core 10004. With one possible exception, x-ray studies have not shown pronounced radiation damage effects. The total energy release upon heating is small up to 900 degrees C and occurs in three broad regions.

7.
Kyobu Geka ; 59(11): 1018-22, 2006 Oct.
Artículo en Japonés | MEDLINE | ID: mdl-17058665

RESUMEN

Seven cases suffered from a chest trauma (stab wound in 6 and impalement injury in 1) were emergently transferred to our hospital. Open thoracotomy was performed for the intolerable bleeding immediately after admission. Injured lung was treated by lobectomy in 1 patient, lingual segmentectomy in 2, lower basal segmentectomy in 2, partial resection in 4 and direct suture in 2. The penetrating trachea was carefully repaired by direct suture with additional midsternal thoracotomy. To accomplish appropriate partial resection of the injured lung, a metallic straight suction tube inserted into a pulmonary stab wound was retracted and a stapling instrument was applied underneath the suction tube. With the segmentectomy and the partial resection, the volume of the residual lung was maximally saved. As a result, all 7 patients were successfully alive.


Asunto(s)
Síndrome de Dificultad Respiratoria/cirugía , Tráquea/lesiones , Tráquea/cirugía , Heridas Penetrantes/cirugía , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad
8.
Neuroreport ; 6(8): 1130-2, 1995 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-7662893

RESUMEN

Expression of cyclin dependent kinase cdk5 and its regulator p35 has been shown in the cytoplasm of adult neurons. Here we demonstrate that another potential regulator of cdk5, cyclin E, is expressed in the nervous system and forms complexes with cdk5. Western blot analyses identifies expression of two forms of cyclin E in the mouse nervous system with the 56 kDa form mainly expressed in neurons and 51 kDa form expressed in astrocytes and oligodendrocytes.


Asunto(s)
Quinasas Ciclina-Dependientes , Ciclinas/biosíntesis , Neuronas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Animales , Northern Blotting , Western Blotting , Células Cultivadas , Corteza Cerebral/citología , Corteza Cerebral/metabolismo , Quinasa 5 Dependiente de la Ciclina , Expresión Génica , Ratones , Proteínas Serina-Treonina Quinasas/genética , Médula Espinal/citología , Médula Espinal/metabolismo
9.
Eur J Pharmacol ; 195(3): 323-31, 1991 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-1831135

RESUMEN

A novel compound, NIP-121, cromakalim and nicorandil caused concentration-dependent relaxation of rat aortas precontracted with 30 mM KCl, with pEC50 (M) values of 8.2, 7.1 and 5.5, respectively. At 60 mM KCl, the vasorelaxation induced by NIP-121 or cromakalim was almost abolished whereas that induced by nicorandil remained. In preparations precontracted with prostaglandin F2 alpha(PGF2 alpha) (10(-5) M), glibenclamide (10(-7) M) and phentolamine (3 x 10(-6), 3 x 10(-5) M) antagonized the relaxation induced by NIP-121 and cromakalim but not that induced by nicorandil. Methylene blue (10(-5) M) showed antagonistic effects against the vasorelaxation induced by nicorandil but not that induced by NIP-121. NIP-121 (10(-7), 10(-6) M) and cromakalim (10(-6), 10(-5) M) significantly increased the 86Rb+ efflux rate in rat aorta. The three compounds inhibited the frequency of spontaneous contractions of the rat portal vein (pIC30; NIP-121 = 8.0, cromakalim = 7.1 and nicorandil = 4.9); glibenclamide and phentolamine antagonized the effects of these compounds. In conclusion, NIP-121 is a more potent K+ channel opener than cromakalim in these tissues. Nicorandil apparently behaves as a K+ channel opener in the rat portal vein, but the vasorelaxation may involve some other mechanisms, such as generation of cyclic GMP.


Asunto(s)
Antihipertensivos/farmacología , Benzopiranos/farmacología , Músculo Liso Vascular/efectos de los fármacos , Niacinamida/análogos & derivados , Oxadiazoles/farmacología , Piperidinas/farmacología , Canales de Potasio/efectos de los fármacos , Pirroles/farmacología , Animales , Aorta Torácica/efectos de los fármacos , Cromakalim , Gliburida/farmacología , Técnicas In Vitro , Masculino , Relajación Muscular/efectos de los fármacos , Niacinamida/farmacología , Nicorandil , Fentolamina/farmacología , Vena Porta/efectos de los fármacos , Cloruro de Potasio/farmacología , Ratas , Ratas Endogámicas , Radioisótopos de Rubidio
10.
J Control Release ; 60(2-3): 199-209, 1999 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-10425326

RESUMEN

The release profiles of acidic and neutral drugs from poly(L-lactic acid) [P(L)LA] matrices were investigated to reveal their release mechanism. Cylindrical matrices (rods; 10 mmx1 mm diameter) were prepared by the heat compression method. The acidic and neutral drugs investigated were dissolved in the P(L)LA rods. It was found that the release profiles consisted of two sequential stages. At the first release stage, P(L)LA remained in an amorphous state and the drugs diffused through the hydrated matrices. At the second release stage, P(L)LA transformed to a semicrystalline state and the drugs diffused through water-filled micropores developed by polymer crystallization. In addition, the drugs were also found to precipitate out as crystals in the rods, resulting in a transformation of the rods into drug-dispersed matrices. On the basis of these findings, we derived a modified diffusion equation for the drug release at the second stage. This equation showed good fits to the release profiles of these drugs. Furthermore, the availability of the derived equation was supported by the acceleration in the fractional drug release rate noted both with decreases in the drug content in the rod and increases in the pH of the medium.


Asunto(s)
Preparaciones de Acción Retardada/química , Ácido Láctico/química , Polímeros/química , Biodegradación Ambiental , Cristalización , Difusión , Griseofulvina/farmacocinética , Concentración de Iones de Hidrógeno , Ibuprofeno/farmacocinética , Indometacina/farmacocinética , Naproxeno/farmacocinética , Progesterona/farmacocinética , Solubilidad , Testosterona/farmacocinética
11.
J Control Release ; 61(3): 295-304, 1999 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-10477802

RESUMEN

We investigated the effect of drug physico-chemical properties on the release of basic drugs from poly(L-lactic acid) (P(L)LA) cylindrical matrices (rods; 10 mmx1 mm diameter). All the rods were revealed to exhibit two-stage diffusion-controlled release profiles resulting from the transformation of P(L)LA from an amorphous to a semicrystalline state in aqueous medium. On the assumption that interactions between polymer carboxyl residues and basic drugs control the drug release rate, we evaluated the strength of these interactions by the drug partition between the polymer and the aqueous medium. In the first release stage, the drugs diffused through the swollen polymer matrix. The polymer-drug interactions shielded the polymer terminal carboxyl residues, thereby resulting in a less hydrated matrix and consequent diminishment of drug diffusion. In the second release stage, the drugs diffused through the water-filled micropores which had developed as a result of polymer crystallization. The stronger polymer-basic drug interactions reduced the drug diffusion rate by decreasing not only the porosity of the matrix, but also the drug partition to the water-filled micropores. It was also found that the fractional drug release rate in the second stage increased with drug content of the rod at the pH where both the polymer carboxyl residues and the drugs were ionized. Since the polymer-drug interactions must be close to saturation with increasing drug content, we believe this result to be due to an increase in the ratio of the drug partition to the water-filled micropores.


Asunto(s)
Materiales Biocompatibles/química , Ácido Láctico/química , Polímeros/química , Clorfeniramina/química , Cristalización , Preparaciones de Acción Retardada , Difusión , Diltiazem/química , Interacciones Farmacológicas , Cinética , Papaverina/química , Poliésteres , Verapamilo/química , Agua/química , Difracción de Rayos X
12.
J Control Release ; 56(1-3): 85-94, 1998 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-9801432

RESUMEN

Effects of drug content and medium pH on the release of papaverine (PAP) from biodegradable poly(l-lactic acid) [P(L)LA] matrix were investigated to reveal the predominant factors affecting the two-stage diffusion-controlled release mechanism. A drug-dissolved cylindrical matrix (rod; 10 mmx1 mm diameter) was prepared by heat compression method. In the case of a PAP content below 10%, pH was found to have a strong effect on the release rate, and drug content was found to have no effect on the release profile. The release profile consisted of two sequential diffusion stages due to P(L)LA transformation from amorphous to the semicrystalline state prior to release. In the first release stage PAP diffused through the swollen matrix. The release accelerated with increasing medium pH due to an increase in water content in the acidic P(L)LA rod. In the second release stage PAP diffused through the water-filled micropores developed as a result of the polymer crystallization. On the assumption that the drug partition between the polymer and the medium in the micropores affects the diffusion and the partition is controlled by pH, we derived a modified diffusion kinetic equation. The observation that the release decelerated with increasing medium pH can be explained by the derived equation as resulting from the increase in the drug partition to the polymer. In the case where the rods contained more than 15% of PAP, the drug precipitated out as crystals during release. Accordingly, these rods showed a slower release.


Asunto(s)
Ácido Láctico/química , Papaverina/química , Inhibidores de Fosfodiesterasa/química , Polímeros/química , Fenómenos Químicos , Química Farmacéutica , Química Física , Preparaciones de Acción Retardada , Difusión , Concentración de Iones de Hidrógeno , Cinética , Poliésteres , Agua/química , Difracción de Rayos X
13.
Neurosurgery ; 42(1): 109-15; discussion 115-6, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9442511

RESUMEN

OBJECTIVE: A drug delivery system using copoly(lactic/glycolic acid) was developed for the intracranial administration of papaverine. A rod-shaped implant prepared by a heat compression method was tested to determine its efficacy in preventing cerebral vasospasm in dogs. METHODS: Sixteen dogs were randomly assigned to one of two groups, i.e., placebo or papaverine. Control angiography was performed, followed by right craniectomy and the induction of subarachnoid hemorrhage by the placement of a clot in the Sylvian fissure. Two pellets, containing either 25 mg of papaverine or no papaverine, were placed in the cistern. In in vitro studies, 56% of the actual papaverine loading was released in the first 4 days and 78% within 8 days. On Day 7, angiography was repeated and the animals were killed. A similar experiment using low-dose pellets containing 5 mg of papaverine, half of which was released within 7 days, was performed with 16 mongrel dogs. RESULTS: There were significant differences between the papaverine- and placebo-treated groups in the reductions of vessel diameters of the internal carotid, middle cerebral, and anterior cerebral arteries on the clot side. The mean concentration of papaverine in the clot was 4.5 x 10(-4) mol/L. The low-dose pellet failed to prevent cerebral vasospasm, although the mean concentration of papaverine in the clot was 2.3 x 10(-5) mol/L. CONCLUSION: A prolonged-release preparation of papaverine that could be implanted intracranially at the time of surgery prevented vasospasm significantly while maintaining an appropriate concentration of papaverine in the cistern.


Asunto(s)
Ataque Isquémico Transitorio/prevención & control , Papaverina/administración & dosificación , Animales , Sangre/metabolismo , Líquido Cefalorraquídeo/metabolismo , Preparaciones de Acción Retardada , Perros , Relación Dosis-Respuesta a Droga , Femenino , Embolia y Trombosis Intracraneal/metabolismo , Masculino , Papaverina/farmacocinética , Papaverina/uso terapéutico , Medicina Preventiva/métodos
14.
J Neurosurg ; 93(1): 62-7, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10883906

RESUMEN

OBJECT: In this study the authors identify and investigate two new classifications of suprasellar arachnoid cysts. METHODS: The authors used computerized tomography cisternography, magnetic resonance (MR) imaging, and neuroendoscopy to investigate nine cases of suprasellar arachnoid cysts. A communicating cyst with early filling and early clearance of a radioopaque tracer was found in seven of nine cases; a communicating cyst with delayed filling and delayed clearance of the tracer was observed in one case; and a noncommunicating cyst was observed in the other. The MR findings indicated a variation in the position of the basilar artery (BA) bifurcation in relation to the ventral surface of the midbrain. A distance existed between the BA bifurcation and the ventral surface of the midbrain in a communicating cyst with early filling, whereas the BA bifurcation was posteriorly displaced in a communicating cyst with delayed filling and also in a noncommunicating cyst, leaving little space between the bifurcation and the ventral surface of the midbrain. Endoscopic observation revealed, in the case of communicating cysts with early filling and early clearance of tracer, that the BA bifurcation is located inside the cyst with no overlying membrane, whereas in a noncommunicating cyst, the BA and its branches can be observed through the transparent membrane of the lesion. CONCLUSIONS: The authors postulate two different types of suprasellar arachnoid cysts: a noncommunicating intraarachnoid cyst of the diencephalic membrane of Liliequist and a communicating cyst that is a cystic dilation of the interpeduncular cistern.


Asunto(s)
Quistes Aracnoideos/etiología , Quistes Aracnoideos/diagnóstico , Quistes Aracnoideos/cirugía , Ventriculografía Cerebral , Preescolar , Diagnóstico por Imagen , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Lactante , Imagen por Resonancia Magnética , Masculino , Silla Turca/patología , Tomografía Computarizada por Rayos X , Ventriculostomía
15.
Neurol Res ; 22(6): 634-41, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11045030

RESUMEN

The purpose of this study was to determine the efficacy of nicardipine prolonged-release implants for preventing vasospasm in a canine SAH model in a dose-escalating placebo-controlled blind fashion. Drug-release kinetics of copoly(lactic/glycolic acid) pellet containing nicardipine were evaluated in vitro. In vivo, 18 dogs were randomly assigned to one of three groups, i.e. placebo, low-dose (0.8 mg), or high-dose (8 mg) nicardipine. Angiography was performed, followed by right craniectomy, the induction of subarachnoid hemorrhage, and the placement of the pellets in the Sylvian fissure. On Day 7 and Day 14, the angiography was repeated. In the first four days, 61.9% of the actual nicardipine loaded was released and within 10 days, 96%. The average percent reductions of vessel diameters in the middle cerebral artery on Day 7 were 43%, 14% and 7% in the placebo, low-dose, and high-dose groups, respectively (p = 0.0319). The mean concentration of nicardipine in the clots on Day 14 was 9.7 x 10(-7) mol-1 l-1 and 5.1 x 10(-6) mol-1 l-1 in the low-dose and high-dose group, respectively. This drug delivery system prevented vasospasm in dogs significantly even at low dose, while maintaining an appropriate concentration of nicardipine in the clot adjacent to the arteries.


Asunto(s)
Nicardipino/administración & dosificación , Hemorragia Subaracnoidea/complicaciones , Vasoespasmo Intracraneal/prevención & control , Animales , Encéfalo/patología , Angiografía Cerebral , Preparaciones de Acción Retardada , Modelos Animales de Enfermedad , Perros , Implantes de Medicamentos , Arteria Cerebral Media/efectos de los fármacos , Arteria Cerebral Media/patología , Nicardipino/uso terapéutico , Hemorragia Subaracnoidea/diagnóstico por imagen , Hemorragia Subaracnoidea/patología , Vasoespasmo Intracraneal/diagnóstico por imagen , Vasoespasmo Intracraneal/patología
16.
J Pharm Sci ; 86(8): 929-34, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9269871

RESUMEN

Dissolution behavior of diclofenac sodium (DS) from wax matrix granules (WMGs) prepared using a twin-screw compounding extruder is closely related to swelling ability and solubility of the rate-controlling agent employed. A swellable and soluble (hydroxypropyl)-cellulose (HPC-SL) generates both an expansion of pores inside WMGs and a structural change observed as cracking on the surface of WMGs. These changes are confirmed by mercury porosimetry. Release of DS was increased with an increase in the amount of HPC-SL in WMGs, but only 35% of DS was released from WMGs containing 73% (w/w) NaCl at the 24 h point of the dissolution. Further, no cracking was observed on the surface of NaCl-containing WMGs. A linear relationship between mean dissolution time (MDT) of DS for WMGs containing different types of HPC (HPC-SL, -M, and -H) and swelling abilities suggests that release of DS could be directly controlled by swelling of HPCs. In addition to this result, an application of the exponential model (Mt/M infinity = kt(n)) introduced by Ritger and Peppas (J. Controlled Release 1987, 5, 23-36) to DS release indicates that case II release plays a critical role in HPC-SL-containing WMGs and Fickian release is predominant in NaCl-containing WMGs since the values of n of WMGs containing 73% (w/w) NaCl and 40% (w/w) HPC-SL are 0.41 and 0.71, respectively. These results suggest that proper selection of rate-controlling agents based on their physicochemical properties (such as swelling ability and solubility) is important in designing WMGs with desired dissolution profiles.


Asunto(s)
Antiinflamatorios no Esteroideos/química , Celulosa/análogos & derivados , Diclofenaco/química , Celulosa/química , Cinética , Solubilidad
17.
J Pharm Sci ; 83(3): 439-43, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8207698

RESUMEN

Scale-up from lab to production is always problematic for the development of pharmaceuticals. In granulation, an optimal formulation of binder solution determined in a lab scale is often different than that in a production scale. A new mathematical procedure to solve this scale-up problem is assessed. Granules were prepared in the two manufacturing scales (2- and 5-kg scale) by using a high-speed mixer granulator. In the manufacturing process, the binder solution plays an essential role in the formation of granules with desired physical properties, in close conformity with the manufacturing scale. A computerized optimizing technique based on a response surface methodology was developed to study the scale-up problem in the manufacturing of granules. For this purpose, a new mathematical function was introduced for the first time, which is namely an integrated optimization function. A universal optimal formulation unaffected by manufacturing scale could be obtained by minimizing the integrated optimization function. Predicted values such as yield, mean granule size, and uniformity of granule size agreed well with experimental ones on both scales. Furthermore, the optimized characteristics measured at the production scale coincided well with those obtained at laboratory scale, suggesting that this approach could be very useful in minimizing scale-up problems.


Asunto(s)
Composición de Medicamentos , Polvos , Industria Farmacéutica , Excipientes , Modelos Teóricos , Tamaño de la Partícula , Análisis de Regresión , Propiedades de Superficie
18.
J Pharm Sci ; 80(10): 935-41, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1784002

RESUMEN

Transdermal delivery systems of 9-beta-D-arabinofuranosyladenine (ara-A), having controlling membranes of various permeabilities, were developed and applied to Azone-pretreated hairless mouse abdominal skin. It was confirmed that the blood concentrations of ara-A and its metabolite 9-beta-D-arabinofuranosylhypoxanthine (ara-H) in hairless mice are controlled by the permeability of the controlling membrane in the transdermal patch. Furthermore, these blood concentrations were found to closely agree with the values obtained from theoretical model calculations. Finally, but importantly, the "micropharmacokinetic" behavior of ara-A in cutaneous tissue could also be predicted. These results suggest that the transdermal patch may be employed in dermal and transdermal ara-A efficacy studies in the treatment of cutaneous herpes virus infections in hairless mice.


Asunto(s)
Vidarabina/administración & dosificación , Administración Cutánea , Animales , Arabinonucleósidos/farmacocinética , Azepinas/farmacología , Cromatografía en Capa Delgada , Técnicas In Vitro , Ratones , Ratones Pelados , Modelos Biológicos , Absorción Cutánea/efectos de los fármacos , Vidarabina/farmacocinética
19.
Surg Neurol ; 56(6): 385-8; discussion 388-9, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11755973

RESUMEN

BACKGROUND: Endodermal cysts usually develop in the subdural space in the anterior spinal cord and rarely occur inside the cranium. Most intracranial endodermal cysts develop in the posterior fossa. We report the first case of an endodermal cyst in the quadrigeminal cistern. CASE DESCRIPTION: The patient was a 71-year-old man who suffered from gait disturbance for 6 months. Although head computed tomography (CT) scanning 4 years previously did not show any cystic lesion, CT and magnetic resonance imaging (MRI) on admission showed a cystic lesion extending from the quadrigeminal cistern to the right ambient cistern. The cyst was subtotally removed via a suboccipital transtentorial approach. The cyst wall consisted of a layer of columnar epithelium and connective tissue. Based on the results of immunostaining, it was diagnosed as an endodermal cyst. CONCLUSIONS: It is possible that the increase of secretion from the cells lining the cyst may have caused a difference in osmotic pressure between the cerebrospinal fluid and the cyst contents, leading to rapid enlargement of the cyst. An endodermal cyst should be removed as completely as possible because its cells have the ability to grow and produce secretions.


Asunto(s)
Quistes del Sistema Nervioso Central/cirugía , Endodermo , Imagen por Resonancia Magnética , Techo del Mesencéfalo/cirugía , Tomografía Computarizada por Rayos X , Anciano , Quistes del Sistema Nervioso Central/diagnóstico , Quistes del Sistema Nervioso Central/patología , Diagnóstico Diferencial , Humanos , Masculino , Examen Neurológico , Techo del Mesencéfalo/patología
20.
Intern Med ; 34(8): 707-12, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8563107

RESUMEN

Summer-type hypersensitivity pneumonitis (SHP), the most prevalent type of HP in Japan, is caused by seasonal mold contamination in the home environment. The causative agent of the disease is Trichosporon cutaneum. The fungus grows in warm, moldy, decaying organic matter, and scatters in the air from the colonizing places. The inhaled fungi sensitize susceptible patients intratracheally and induce the disease. Glucuronoxylomannan of the fungus has a potent antigenicity that causes granulomatous alveolitis. Assay of anti-T. cutaneum antibody is very useful to establish the diagnosis of the disease because the antibody activity is virtually positive in all cases of the disease. Elimination of T. cutaneum from the colonizing places prevents recrudescence. SHP, a new form of HP, had been considered to be peculiar to Japan, but the first case of SHP outside Japan was identified in Korea last year. Soon it will be recognized in many countries of temperate and tropical clime.


Asunto(s)
Alveolitis Alérgica Extrínseca , Alveolitis Alérgica Extrínseca/diagnóstico , Alveolitis Alérgica Extrínseca/epidemiología , Alveolitis Alérgica Extrínseca/etiología , Alveolitis Alérgica Extrínseca/terapia , Humanos , Japón/epidemiología , Estaciones del Año
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