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1.
Eur J Clin Microbiol Infect Dis ; 43(3): 459-467, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38172403

RESUMEN

PURPOSE: During the last decade, the incidence of anaerobic bacteremia (AB) has been increasing. Patients with AB may develop complex underlying diseases, which can occasionally be accompanied by fatal or fulminant outcomes. However, the risk factors for AB-related mortality remain unclear. Herein, we sought to elucidate the risk factors for AB-related mortality. METHODS: In this multicenter, retrospective, observational study, we enrolled patients with culture-proven AB from six tertiary hospitals in Japan, between January 2012 and December 2021. Data on patient and infection characteristics, laboratory findings, treatment, and outcome were collected, and their associations with mortality were analyzed. RESULTS: A total of 520 participants were included. The 30-day mortality in the study cohort was 14.0% (73 patients), and malignant tumors were frequently observed comorbidities in 48% of the entire cohort. Multivariable logistic regression analysis showed a Charlson comorbidity score of > 6, serum creatinine level of > 1.17 mg/dL, and hypotension to be independent risk factors for 30-day mortality in AB (odds ratios [ORs] 2.12, 2.25, and 5.12, respectively; p < 0.05), whereas drainage significantly reduced this risk (OR, 0.28; p < 0.0001). Twelve patients (2.3% of the whole cohort and 16.4% of the deceased patients) presented with extremely rapid progression leading to fatal outcome, consistent with "fulminant AB." CONCLUSIONS: This study identified acute circulatory dysfunction and performance of drainage as independent predictive factors for 30-day AB-related mortality and revealed the existence of a fulminant AB sub-phenotype. Our findings could serve as a practical guide to predict the clinical outcomes of AB.


Asunto(s)
Bacteriemia , Humanos , Estudios Retrospectivos , Anaerobiosis , Estudios de Cohortes , Factores de Riesgo , Bacteriemia/microbiología , Antibacterianos/uso terapéutico
2.
AJNR Am J Neuroradiol ; 28(5): 839-43, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17494653

RESUMEN

BACKGROUND AND PURPOSE: Compared with the image intensifier (I.I.)-TV system, the flat panel detector (FPD) system of direct conversion type has several theoretic advantages, such as higher spatial resolution, wide dynamic range, and no image distortion. The purpose of this study was to compare the image quality of 3D digital subtraction angiography (DSA) in the FPD and conventional I.I.-TV systems using a vascular phantom. MATERIALS AND METHODS: An anthropomorphic vascular phantom was designed to simulate the various intracranial aneurysms with aneurysmal bleb. The tubes of this vascular phantom were filled with 2 concentrations of contrast material (300 and 150 mg I/mL), and we obtained 3D DSA using the FPD and I.I.-TV systems. First, 2 blinded radiologists compared the volume-rendering images for 3D DSA on the FPD and I.I.-TV systems, looking for pseudostenosis artifacts. Then, 2 other radiologists independently evaluated both systems for the depiction of the simulated aneurysm and aneurysmal bleb using a 5-point scale. RESULTS: For the degree of the pseudostenosis artifacts at the M1 segment of the middle cerebral artery at 300 mg I/mL, 3D DSA with FPD system showed mild stenoses, whereas severe stenoses were observed at 3D DSA with I.I.-TV system. At both concentrations, the FPD system was significantly superior to I.I.-TV system regarding the depiction of aneurysm and aneurysmal bleb. CONCLUSION: Compared with the I.I.-TV system, the FPD system could create high-resolution 3D DSA combined with a reduction of the pseudostenosis artifacts.


Asunto(s)
Angiografía de Substracción Digital/instrumentación , Angiografía de Substracción Digital/métodos , Angiografía Cerebral/instrumentación , Angiografía Cerebral/métodos , Aneurisma Intracraneal/diagnóstico por imagen , Angiografía de Substracción Digital/normas , Artefactos , Angiografía Cerebral/normas , Humanos , Imagenología Tridimensional , Modelos Anatómicos , Fantasmas de Imagen , Reproducibilidad de los Resultados
3.
AJNR Am J Neuroradiol ; 28(4): 645-50, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17416814

RESUMEN

BACKGROUND AND PURPOSE: Compared with image intensifier television (I.I.-TV) system, an angiography system using the flat panel detector (FPD) of direct conversion type has a high spatial resolution, which may improve image quality, reduce patient exposure, or both. Our purpose was to evaluate the detection of simulated aneurysmal blebs under dose reduction with the FPD system in comparison with the I.I.-TV system. MATERIALS AND METHODS: A vascular phantom was designed to simulate various intracranial aneurysms with and without blebs, and this phantom was filled with 3 different concentrations of contrast material (300, 150, and 100 mg I/mL). 2D digital subtraction angiography (DSA) at low-dose mode of FPD system was compared with 2D DSA at a standard-dose mode of FPD system and a conventional mode of I.I.-TV system. Data analysis was based on 171 observations (57 aneurysms [20 with bleb and 37 without bleb] x 3 contrast material concentrations) by each of 7 radiologists, and the detection performances of blebs were compared using a receiver operating characteristic (ROC) analysis. RESULTS: The mean dose measurements with a phantom during 2D DSA were 0.36 mGy/frame with low-dose mode of FPD system, 0.72 mGy/frame with standard-dose mode of FPD system and 0.76 mGy/frame with I.I.-TV system. The mean Az at 100 mg I/mL was significantly higher for low-dose mode of FPD than for conventional-dose mode of I.I.-TV mean Az, 0.85 versus 0.56; P < .01), though differences were not significant with 150 and 300 mg I/mL between both systems. CONCLUSION: The FPD system allows a considerable dose reduction during 2D DSA without loss of the image quality.


Asunto(s)
Angiografía de Substracción Digital , Angiografía Cerebral , Aneurisma Intracraneal/diagnóstico por imagen , Dosis de Radiación , Intensificación de Imagen Radiográfica/instrumentación , Simulación por Computador , Medios de Contraste , Humanos , Fantasmas de Imagen , Curva ROC , Televisión
4.
J Dent Res ; 85(2): 144-9, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16434732

RESUMEN

We previously reported that amelogenin isoforms M180 and leucine-rich amelogenin peptide (LRAP) are expressed in the periodontal region, and that their absence is associated with increased cementum defects in amelogenin-knockout (KO) mice. The aim of the present study was to characterize the functions of these isoforms in osteoclastogenesis and in the proliferation and migration of cementoblast/periodontal ligament cells. The co-cultures of wild-type (WT) osteoclast progenitor and KO cementoblast/periodontal ligament cells displayed more tartrate-resistant acid phosphatase (TRAP)-positive cells than the co-cultures of WT cells. The addition of LRAP to both co-cultures significantly reduced RANKL expression and the TRAP-positive cells. Proliferation and migration rates of the KO cementoblast/periodontal ligament cells were lower than those of WT cells and increased with the addition of either LRAP or P172 (a porcine homolog of mouse M180). Thus, we demonstrate the regulation of osteoclastogenesis by LRAP, and the proliferation and migration of cementoblast/periodontal ligament cells by LRAP and P172.


Asunto(s)
Cemento Dental/fisiología , Proteínas del Esmalte Dental/fisiología , Osteoclastos/fisiología , Ligamento Periodontal/fisiología , Amelogenina , Animales , Proteínas Portadoras/biosíntesis , Movimiento Celular/efectos de los fármacos , Movimiento Celular/fisiología , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Técnicas de Cocultivo , Cemento Dental/citología , Cemento Dental/efectos de los fármacos , Proteínas del Esmalte Dental/farmacología , Glicoproteínas de Membrana/biosíntesis , Ratones , Ratones Noqueados , Osteoclastos/citología , Osteoclastos/efectos de los fármacos , Ligamento Periodontal/citología , Ligamento Periodontal/efectos de los fármacos , Isoformas de Proteínas/farmacología , Isoformas de Proteínas/fisiología , Ligando RANK , Receptor Activador del Factor Nuclear kappa-B , Proteínas Recombinantes/farmacología , Organismos Libres de Patógenos Específicos , Porcinos
5.
Eur J Pain ; 20(7): 1155-65, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27030509

RESUMEN

BACKGROUND: TRPA1 is a Ca-permeable nonselective cation channel expressed in sensory neurons and acts as a nocisensor. Recent reports show that some monoterpenes, a group of naturally occurring organic compounds, modulate TRP channel activity. Here, we report that limonene, being contained in citrus fruits and mushrooms, shows a unique bimodal action on TRPA1 channel. METHODS: We examine the effects of limonene on sensory neurons from wild-type, TRPV1- and TRPA1-gene-deficient mice and on heterologously expressed channels in vitro. Molecular determinants were identified with using mutated channels. Cellular excitability is monitored with ratiometric Ca imaging. Nociceptive and analgesic actions of limonene are also examined in vivo. RESULTS: In wild-type mouse sensory neurons, limonene increased the intracellular Ca(2+) concentration ([Ca(2+) ]i ), which was inhibited by selective inhibitors of TRPA1 but not TRPV1. Limonene-responsive neurons highly corresponded to TRPA1 agonist-sensitive ones. Limonene failed to stimulate sensory neurons from the TRPA1 (-/-) mouse. Heterologously expressed mouse TRPA1 was activated by limonene. Intraplantar injection of limonene elicited acute pain, which was significantly less in TRPA1 (-/-) mice. Systemic administration of limonene reduced nociceptive behaviours evoked by H2 O2 . In both heterologously and endogenously expressed TRPA1, a low concentration of limonene significantly inhibited H2 O2 -induced TRPA1 activation. TRPA1 activation by limonene was abolished in H2 O2 -insensitive cysteine-mutated channels. CONCLUSIONS: Topically applied limonene stimulates TRPA1, resulting in elicitation of acute pain, but its systemic application inhibits nociception induced by oxidative stress. Because limonene is a safe compound, it may be utilized for pain control due to its inhibition of TRPA1 channels. What does this study add: Limonene, a monoterpene in essential oils of various plants, has been known for its antitumor and anti-inflammatory properties. However, molecular basis of their actions has not been identified. This study shows that limonene activates nociceptive TRPA1 and elicits acute pain, when it is topically applied. In addition, systemic application of limonene exerts inhibitory effects on nociception induced by an oxidative stress-induced TRPA1 activation.


Asunto(s)
Dolor Agudo/etiología , Analgésicos/farmacología , Ciclohexenos/farmacología , Nocicepción/efectos de los fármacos , Células Receptoras Sensoriales/efectos de los fármacos , Canal Catiónico TRPA1/efectos de los fármacos , Terpenos/farmacología , Animales , Técnicas de Cultivo de Célula , Células HEK293 , Humanos , Limoneno , Masculino , Ratones , Ratones Endogámicos C57BL , Canal Catiónico TRPA1/fisiología
6.
Methods Inf Med ; 54(6): 515-21, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26063536

RESUMEN

OBJECTIVES: When patients complete questionnaires during health checkups, many of their responses are subjective, making topic extraction difficult. Therefore, the purpose of this study was to develop a model capable of extracting appropriate topics from subjective data in questionnaires conducted during health checkups. METHODS: We employed a latent topic model to group the lifestyle habits of the study participants and represented their responses to items on health checkup questionnaires as a probability model. For the probability model, we used latent Dirichlet allocation to extract 30 topics from the questionnaires. According to the model parameters, a total of 4381 study participants were then divided into groups based on these topics. Results from laboratory tests, including blood glucose level, triglycerides, and estimated glomerular filtration rate, were compared between each group, and these results were then compared with those obtained by hierarchical clustering. RESULTS: If a significant (p < 0.05) difference was observed in any of the laboratory measurements between groups, it was considered to indicate a questionnaire response pattern corresponding to the value of the test result. A comparison between the latent topic model and hierarchical clustering grouping revealed that, in the latent topic model method, a small group of participants who reported having subjective signs of urinary disorder were allocated to a single group. CONCLUSIONS: The latent topic model is useful for extracting characteristics from a small number of groups from questionnaires with a large number of items. These results show that, in addition to chief complaints and history of past illness, questionnaire data obtained during medical checkups can serve as useful judgment criteria for assessing the conditions of patients.


Asunto(s)
Estado de Salud , Estilo de Vida , Modelos Estadísticos , Reconocimiento de Normas Patrones Automatizadas/métodos , Examen Físico/estadística & datos numéricos , Autoinforme , Simulación por Computador , Interpretación Estadística de Datos , Humanos , Japón , Tamaño de la Muestra
7.
Brain Res ; 660(1): 158-61, 1994 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-7827993

RESUMEN

Effect of N,N-diethyldithiocarbamate (DDC), an inhibitor for cytosolic superoxide dismutase, on an ionomycin-induced increase in oxidative metabolism was examined in cerebellar neurons dissociated from the rats, using a flow cytometer and 2',7'-dichlorofluorescin diacetate and fluo-3-AM, fluorescent dyes for intracellular hydrogen peroxide and Ca2+, respectively. DDC reduced the ionomycin-induced augmentation of 2',7'-dichlorofluorescin fluorescence in a dose-dependent manner. DDC did not affect cellular content of 2',7'-dichlorofluorescin and ionomycin-induced increase in intracellular Ca2+ concentration. Results indicate that ionomycin increases the formation of superoxide anion in brain neuron.


Asunto(s)
Cerebelo/metabolismo , Ditiocarba/farmacología , Fluoresceínas/metabolismo , Ionomicina/farmacología , Neuronas/metabolismo , Compuestos de Anilina , Animales , Cerebelo/citología , Colorantes Fluorescentes , Oxidación-Reducción/efectos de los fármacos , Ratas , Ratas Wistar , Xantenos
8.
Brain Res ; 662(1-2): 259-62, 1994 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-7859081

RESUMEN

Effects of amyloid beta protein fragment 25-35, A beta P(25-35), on membrane permeability and cell viability were examined in the brain neurons dissociated from the rats using a flow cytometer and two fluorescent dyes, fluo-3 to monitor intracellular Ca2+ concentration ([Ca2+]i) of neurons and ethidium which is impermeant to membranes of intact neurons to stain dead and dying neurons. A beta P(25-35) augmented fluo-3 fluorescence of some neurons at concentrations greater than 1 microM, indicating an increase in [Ca2+]i although other neurons (about 80% of total neurons) did not respond to A beta P(25-35) even at 10 microM. A beta P(25-35) at 1 microM or greater increased dose-dependently the number of ethidium-stained neurons, suggesting a dose-dependent increase in number of dead and dying neurons. Results suggest that A beta P(25-35) increases the membrane permeability of brain neurons, resulting in a destabilized intracellular homeostasis that leads to neuonal death.


Asunto(s)
Péptidos beta-Amiloides/toxicidad , Encéfalo/citología , Neuronas/efectos de los fármacos , Fragmentos de Péptidos/toxicidad , Compuestos de Anilina , Animales , Encéfalo/efectos de los fármacos , Calcio/metabolismo , Muerte Celular/efectos de los fármacos , Permeabilidad de la Membrana Celular/efectos de los fármacos , Etidio , Citometría de Flujo , Ratas , Ratas Wistar , Xantenos
9.
Artículo en Inglés | MEDLINE | ID: mdl-10621949

RESUMEN

1. Three patients with Alzheimer's disease (AD) and three healthy controls (HC) were examined for eye-head coordination. Regional cerebral blood flow (rCBF) was measured in AD patients. 2. Eye-head coordination was analyzed using a Vision analyzer, and magnetic sensors. The authors measured the rCBF with 123I-IMP, and 99mTc-ECD SPECT. 3. AD reduced gaze accuracy and head movements, and prolonged the latency of saccade as compared to HC. AD patients had a tendency to focus on the target by using eye movements only. 4. AD reduced the rCBF in the inferior parietal part and the visual area, relative to the motor area. Damage of these areas may have caused the eye-head coordination disorders in the AD patients.


Asunto(s)
Enfermedad de Alzheimer/fisiopatología , Circulación Cerebrovascular/fisiología , Movimientos Oculares/fisiología , Movimientos de la Cabeza/fisiología , Desempeño Psicomotor/fisiología , Adulto , Anciano , Enfermedad de Alzheimer/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Femenino , Humanos , Masculino , Corteza Motora/diagnóstico por imagen , Lóbulo Parietal/irrigación sanguínea , Lóbulo Parietal/diagnóstico por imagen , Movimientos Sacádicos/fisiología , Tomografía Computarizada de Emisión de Fotón Único , Campos Visuales/fisiología
10.
Phytochemistry ; 51(4): 567-73, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10389269

RESUMEN

Five new spirostanol saponins and a new furostanol saponin were isolated from the fresh bulbs of Lilium candidum. Their structures were elucidated on the basis of spectroscopic analysis, including two-dimensional NMR spectroscopic techniques and the result of acid hydrolysis. The isolated saponins contained a branched triglycoside moiety assigned as O-alpha-L-rhamnopyranosyl-(1-->2)-O-[beta-D-glucopyranosyl-(1-->6)]-beta - D-glucopyranose with the formation of an O-glycosidic linkage to C-3 of the aglycone as the common structural feature. The inhibitory activity of the saponins on Na+/K+ ATPase was evaluated.


Asunto(s)
Plantas Medicinales/química , Saponinas/aislamiento & purificación , Conformación de Carbohidratos , Secuencia de Carbohidratos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/aislamiento & purificación , Inhibidores Enzimáticos/farmacología , Datos de Secuencia Molecular , Saponinas/química , Saponinas/farmacología , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , Análisis Espectral
11.
Phytochemistry ; 41(4): 1225-30, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8728721

RESUMEN

A new phenylpropanoid ester of a pyrroline derivative and two new steroidal saponins were isolated from the fresh bulbs of Lilium martagon, along with several previously known compounds. The structures of the new compounds were determined by spectroscopic data, hydrolysis, and by comparison with spectral data of known compounds to be (-)-5-hydroxy-3-methyl-3-pyrrolin-2-one 5-O-(6-O-p-coumaroyl-beta-D- glucopyranoside), (25S)-spirost-5-ene-3 beta,17 alpha, 27-triol 3-O-[O-beta-D-glucopyranosyl-(1-->2)-O-beta-D-glucopyranosyl- (1-->4)-beta-D-glucopyranoside] and (25S)-5 alpha-spirostane-3 beta,17 alpha,27-triol 3-O-[O-beta-D-glucopyranosyl-(1-->2)-O-beta-D-glucopyranosyl-(1-->4)-bet a-D- glucopyranoside], respectively. Lilium martagon crosses well with L. hansonii to produce a valuable garden hybrid lily. In this study, the secondary metabolites of L. martagon were revealed to be closely related to those of L. hansonii, giving a good example of the correlation between the secondary metabolites and cross-compatibility.


Asunto(s)
Plantas/química , Saponinas/aislamiento & purificación , Espirostanos , Secuencia de Carbohidratos , Ésteres , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular , Saponinas/química , Análisis Espectral
12.
Photochem Photobiol ; 57(6): 934-40, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8367534

RESUMEN

We established a monoclonal antibody (DEM-1) that recognizes UV-induced DNA damage other than cyclobutane pyrimidine dimers or (6-4)photoproducts. The binding of DEM-1 antibody to 254 nm UV-irradiated DNA increased with subsequent exposure to UV wavelengths longer than 310 nm, whereas that of the 64M-2 antibody specific for the (6-4)photoproduct decreased with this treatment. Furthermore, the increase in DEM-1 binding was inhibited by the presence of the 64M-2 antibody during the exposure. We concluded that the DEM-1 antibody specifically recognized the Dewar photoproduct, which is the isomeric form of the (6-4)photoproduct. The DEM-1 antibody, however, also bound to DNA irradiated with high fluences of 254 nm UV, suggesting that 254 nm UV could induce Dewar photoproducts without subsequent exposure to longer wavelengths of UV. Furthermore, an action spectral study demonstrated that 254 nm was the most efficient wavelength for Dewar photoproduct induction in the region from 254 to 365 nm, as well as cyclobutane dimers and (6-4)photoproducts, although the action spectrum values in the UV-B region were significantly higher compared with those for cyclobutane dimer and (6-4)photoproduct induction.


Asunto(s)
Anticuerpos Monoclonales , ADN/efectos de la radiación , Animales , Especificidad de Anticuerpos , Secuencia de Bases , Bovinos , ADN/química , ADN/inmunología , Daño del ADN/inmunología , Hibridomas/inmunología , Técnicas In Vitro , Ratones , Fotoquímica , Rayos Ultravioleta/efectos adversos
13.
J Bone Joint Surg Am ; 81(3): 385-90, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10199277

RESUMEN

BACKGROUND: After reduction of a shoulder dislocation, the torn edges of a Bankart lesion need to be approximated for healing during immobilization. The position of immobilization has traditionally been adduction and internal rotation, but there is little direct evidence to support or discredit the use of this position. The purpose of the present study was to determine the relationship between the position of the arm and the coaptation of the edges of a simulated Bankart lesion created in cadaveric shoulders. METHODS: Ten thawed fresh-frozen cadaveric shoulders were used for experimentation. All of the muscles were removed to expose the joint capsule. A simulated Bankart lesion was created by sectioning the anteroinferior aspect of the capsule from the labrum. With linear transducers attached to the anteroinferior and inferior portions of the Bankart lesion, the opening and closing of the lesion were recorded with the arm in 0, 30, 45, and 60 degrees of elevation in the coronal and sagittal planes as well as with the arm in rotation from full internal to full external rotation in 10-degree increments. RESULTS: With the arm in adduction, the edges of the simulated Bankart lesion were coapted in the range from full internal rotation to 30 degrees of external rotation. With the arm in 30 degrees of flexion or abduction, the edges of the lesion were coapted in neutral and internal rotation but were separated in external rotation. At 45 and 60 degrees of flexion or abduction, the edges were separated regardless of rotation. CONCLUSIONS: The present study demonstrated that, in the cadaveric shoulder, there was a so-called coaptation zone in which the edges of a simulated Bankart lesion were kept approximated without the surrounding muscles.


Asunto(s)
Inmovilización , Luxación del Hombro/terapia , Anciano , Anciano de 80 o más Años , Humanos , Técnicas In Vitro , Persona de Mediana Edad , Movimiento , Luxación del Hombro/fisiopatología , Articulación del Hombro/fisiopatología
14.
Mutat Res ; 278(2-3): 193-5, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1372705

RESUMEN

A micronucleus test was conducted on the peripheral blood of mice and rats utilizing acridine orange-coated slides (AO-coated method) after oral administration of benzene. Blood was sampled at 0, 24, 48, and 72 h after administration of benzene at doses of 500, 1000, and 2000 mg/kg in both mice and rats. The highest occurrence of micronucleated reticulocytes (MNRETs) was observed at 48 h after administration in both species. Species differences was found in the frequency of MNRETs, with the number being lower in rats than in mice. The present results indicate that the micronucleus test can easily detect chromosome aberrations in peripheral blood induced by benzene administration in both mice and rats. Furthermore, the AO-coated method used in this study was simpler to perform and allowed for easier detection of the effect than the conventional method.


Asunto(s)
Benceno/toxicidad , Mutágenos/toxicidad , Reticulocitos/efectos de los fármacos , Naranja de Acridina , Animales , Relación Dosis-Respuesta a Droga , Masculino , Ratones , Ratones Endogámicos , Pruebas de Micronúcleos/métodos , Mitomicina/toxicidad , Ratas , Ratas Endogámicas , Especificidad de la Especie
15.
Mutat Res ; 223(4): 407-10, 1989 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2747728

RESUMEN

The effect of route of administration on the outcome of the micronucleus test was studied in 2 laboratories by administering the model chemical benzene intraperitoneally (i.p.) and orally (p.o.) to 2 strains of mice: MS/Ae and CD-1. On the basis of results obtained in a small-scale acute toxicity study and in a pilot micronucleus test, full-scale micronucleus tests were performed with a 24-h sampling time at doses of 250, 500, 1000, and 2000 mg/kg i.p. and 500, 1000, 2000, and 4000 mg/kg p.o. In both strains of mice, a higher incidence of micronucleated polychromatic erythrocytes (MNPCEs) was observed after p.o. administration. The ratio of polychromatic erythrocytes (PCEs) to total erythrocytes decreased more markedly at higher doses i.p. in both strains. Thus, benzene induced more micronuclei via the p.o. route, while inhibitory effects on bone marrow cells were stronger after i.p. administration.


Asunto(s)
Benceno/administración & dosificación , Pruebas de Micronúcleos , Mutágenos/administración & dosificación , Administración Oral , Animales , Benceno/toxicidad , Inyecciones Intraperitoneales , Dosificación Letal Mediana , Masculino , Ratones , Proyectos Piloto
16.
Arch Oral Biol ; 43(11): 889-98, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9821512

RESUMEN

To analyse regional variations in extracellular matrix components of adult rat temporomandibular joint discs, immunohistochemical techniques were used to examine the localization of two small dermatan-sulphate proteoglycans, biglycan and decorin, and a large chondroitin-sulphate proteoglycan. Staining for biglycan was intense in the posterior band, although it had a rather weak and even distribution throughout the disc. In contrast, staining for decorin was faint in the intermediate zone and the central part of the posterior band, moderate in the anterior and posterior attachments and most intense in the junction between the anterior band and attachment. The upper surface of the disc stained more intensely than the lower. Similarly, there was intense staining for large chondroitin-sulphate proteoglycan in the peripheral band, but both the anterior and the temporal parts of the posterior attachments were faintly stained. These results demonstrate marked regional differences in the expression of biglycan, decorin and large chondroitin-sulphate proteoglycan in the temporomandibular joint discs of adult rats. These variations probably reflect the different biomechanical environments caused by the complicated articulatory functions of the temporomandibular joint.


Asunto(s)
Sulfatos de Condroitina/metabolismo , Proteoglicanos/metabolismo , Disco de la Articulación Temporomandibular/metabolismo , Animales , Biglicano , Decorina , Matriz Extracelular/metabolismo , Proteínas de la Matriz Extracelular , Inmunohistoquímica/métodos , Masculino , Ratas , Ratas Wistar , Coloración y Etiquetado/métodos
17.
Am J Sports Med ; 29(5): 633-40, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11573923

RESUMEN

Twelve cadaveric shoulders were used to determine the effects of release of the superior capsule and the coracohumeral ligament on the strain in the repaired rotator cuff tendon. A rotator cuff tear (2 cm wide and 1.5 cm long) was created and repaired under a 3-kg tensile force. The strain in the repaired tendon was measured with use of linear transducers with the arm in 50 different positions. Release of either the superior capsule or the coracohumeral ligament diminished the tension of the repaired rotator cuff by an average of 25% with the arm in adduction. Release of both of these structures further reduced the tension by an average of 44% in adduction and 43% to 60% with the arm in 15 degrees of elevation. The maximum reduction of tension in the repaired rotator cuff occurred when both the superior capsule and coracohumeral ligament were divided and when the arm was positioned in adduction and in 60 degrees of external rotation. Release of the coracohumeral ligament is equally as efficient as releasing the superior capsule in reducing the strain of the repaired rotator cuff. Releasing both structures seems to be desirable when releasing one structure or the other is not sufficient.


Asunto(s)
Cápsula Articular/cirugía , Ligamentos Articulares/cirugía , Lesiones del Manguito de los Rotadores , Esguinces y Distensiones/cirugía , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Cadáver , Femenino , Humanos , Masculino , Persona de Mediana Edad , Manguito de los Rotadores/fisiopatología , Manguito de los Rotadores/cirugía , Articulación del Hombro
18.
Am J Sports Med ; 29(4): 488-92, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11476391

RESUMEN

We studied the strain on the superior labrum of 10 fresh-frozen cadaveric shoulders with the arm in simulated positions of a pitching motion. We used linear transducers to measure the strain in both the anterior and posterior superior labrum with the arm in various planes and rotations simulating the motions of pitching: early cocking, late cocking, acceleration, deceleration, and follow-through. Predetermined loads, according to the percent of maximum voluntary contraction of the biceps muscle during each phase of pitching, were calculated and applied to the long head of the biceps tendon using a spring device. Only during the late cocking phase, when the arm was in maximal external rotation, was the increase in strain statistically significant for the anterior and posterior portions and the strain on the posterior portion significantly greater than that on the anterior portion of the labrum. The increased strain in the posterior portion may be due to the anatomic orientation of the long head of the biceps tendon at the superior labrum. The increased strain in the late cocking phase may contribute to the detachment of the labrum with the eccentric contraction of the biceps muscle that occurs with rapid extension of the elbow.


Asunto(s)
Movimiento/fisiología , Articulación del Hombro/fisiología , Deportes/fisiología , Anciano , Anciano de 80 o más Años , Brazo/fisiología , Cadáver , Humanos , Húmero/fisiología , Persona de Mediana Edad , Rango del Movimiento Articular/fisiología , Escápula/fisiología , Estrés Mecánico
19.
Am J Sports Med ; 29(6): 788-94, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11734494

RESUMEN

In 14 cadaveric shoulders, a rotator cuff tear (2 cm wide and 1.5 cm long) was created and repaired under a 3-kg tensile force with the arm in adduction. Strain on the repaired tendon was measured at 0 degrees, 15 degrees, 30 degrees, and 45 degrees of elevation in the sagittal, scapular, and coronal planes and from 60 degrees of internal rotation to 60 degrees of external rotation. The strain in all of the planes decreased significantly with the arm elevated more than 30 degrees. With 30 degrees of elevation in the scapular and coronal planes, the strain increased in internal rotation and decreased in external rotation. In all of the positions measured, the strain in the sagittal plane was significantly greater than in the other planes. We concluded that more than 30 degrees of elevation in the coronal or scapular plane and rotation ranging from 0 degrees to 60 degrees of external rotation compose the safe range of motion after repair of the rotator cuff.


Asunto(s)
Manguito de los Rotadores/cirugía , Articulación del Hombro/fisiología , Traumatismos de los Tendones/fisiopatología , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Terapia por Ejercicio , Humanos , Persona de Mediana Edad , Rango del Movimiento Articular , Rotación , Lesiones del Manguito de los Rotadores , Rotura/fisiopatología , Traumatismos de los Tendones/rehabilitación , Traumatismos de los Tendones/cirugía
20.
J Pharm Pharmacol ; 42(10): 720-2, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1982145

RESUMEN

Polyvinyl alcohol hydrogels which contained phospholipid, egg yolk lecithin or hydrogenated soya lecithin were designed as a transrectal delivery system for propranolol hydrochloride. The hydrogel preparations containing phospholipid were prepared by a low-temperature crystallization method. The release profile of propranolol from hydrogel preparations containing phospholipid complied with Fickian diffusion (Higuchi model). The release of propranolol from the hydrogel preparation decreased with higher contents of phospholipid (approximately 2% w/w). In rats plasma concentrations of propranolol after rectal administration of hydrogel preparations containing phospholipid (1 and 2% w/w) were prolonged compared with those of rats receiving preparations without phospholipid.


Asunto(s)
Preparaciones de Acción Retardada , Vehículos Farmacéuticos , Fosfolípidos/química , Alcohol Polivinílico/química , Propranolol/administración & dosificación , Administración Rectal , Animales , Disponibilidad Biológica , Química Farmacéutica , Geles , Masculino , Fosfatidilcolinas/química , Propranolol/farmacocinética , Ratas , Ratas Endogámicas
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