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2.
J Occup Environ Hyg ; 12(10): 692-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25897559

RESUMEN

Air concentrations near pollutant sources can be modeled using two-zone and turbulent diffusion models. Each type of model requires a specific pollutant transport parameter: the interzonal air flow (ß) is used in the two-zone model and the turbulent diffusion coefficient (DT) in the diffusion model. In this study ß and DT were determined experimentally by using concentrations measured around the release of a tracer vapor. A robot arm provided motion in the space near the source to simulate worker actions. Eighty-two experiments were conducted at two room locations and with different robot arm motion programs. ß and DT for were calculated using room geometry, ventilation parameters and the measured concentrations during the experiments. The near zone geometry was a 0.4 m hemisphere. The presence of motion in the vicinity of the source was important for the appropriate application of both models. The values of ß were log-normally distributed with a mean of 2.03 m3/min, a geometric mean (GM) of 1.65 m3/min (1.42-1.93 95% C.I.) and a geometric standard deviation of 1.82. DT was also log-normally distributed with a mean of 0.586 m2/min, a GM of 0.545 m2/min (0.493-0.600 95% C.I.) and GSD of 1.45. The location within the room had an influence on the value of both ß and DT. The use of random airspeed and the free surface area around the source was confirmed as an appropriate method for determining ß. A recently developed algorithm was supported as useful for determination of DT. The results strengthen the application of both the two-zone and turbulent diffusion models for worker exposure modeling.


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Monitoreo del Ambiente/métodos , Modelos Teóricos , Exposición Profesional/análisis , Acetona/análisis , Movimientos del Aire , Difusión , Ventilación
3.
Clin Oral Investig ; 17(3): 887-96, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22699659

RESUMEN

OBJECTIVES: Botulinum toxin A (Botox) is increasingly used for treatment of muscle hyperfunction. For a better understanding of the possible morphologic and chewing changes in patients induced by a therapy with Botox, muscle fiber and myosin heavy chain (MyHC) mRNA alterations were examined in this animal study. MATERIALS AND METHODS: The investigation was carried out on 14-week-old pigs (seven treated animals, eight controls; calculated animal size with a power of 0.5). To initialise the total immobilisation of the right masseter, the Botox injection was distributed into ten areas. After a 56-day period, muscle tissue was taken from the left and right side of the masseter (three regions), temporal (two regions), medial pterygoid and geniohyoid muscles using a standardized method. The muscle fiber cross sections were examined immunohistochemically. Fiber staining was accomplished with antibodies to specific MyHC isoforms. The MyHC mRNA changes were analysed using real-time RT-PCR. RESULTS: Muscles adapt to such stress by changing fiber types and MyHC mRNA content. Paralysed masseters display atrophic changes while other masticatory muscles show hypertrophic changes. The results indicated that the typical distributions of type IIa und IIb fiber types in masticatory muscles were increased in the masseter muscles due to Botox application. On the other hand, the masseters without Botox in the treated group showed a significant increase of type I MyHC. CONCLUSIONS: Application of Botox may lead to uncontrolled structural changes in affected and unaffected muscles. CLINICAL RELEVANCE: Treatment of muscle hypertrophy with Botox may cause muscle imbalance.


Asunto(s)
Toxinas Botulínicas Tipo A/farmacología , Parálisis Facial/tratamiento farmacológico , Músculo Masetero/efectos de los fármacos , Músculos Masticadores/patología , Cadenas Pesadas de Miosina/genética , Miosinas del Músculo Esquelético/genética , Animales , Toxinas Botulínicas Tipo A/uso terapéutico , Hipertrofia , Músculos Masticadores/química , Músculos Masticadores/efectos de los fármacos , Desnervación Muscular , Atrofia Muscular/tratamiento farmacológico , Atrofia Muscular/patología , Cadenas Pesadas de Miosina/efectos de los fármacos , ARN Mensajero/análisis , Reacción en Cadena en Tiempo Real de la Polimerasa , Porcinos
4.
J Physiol Pharmacol ; 68(2): 181-189, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28614767

RESUMEN

Progressive muscle wasting, frequently associated with inflammation, muscle fibre degeneration and fibrosis, is a characteristic of DMD (Duchenne muscular dystrophy). Its most common used animal model, the mdx mouse, however can overcome muscle degeneration by regeneration processes and is for this reason not suitable to answer all scientific questions. The aim of this study was to evaluate the ability of botulinum toxin A (BTX-A) in breaking down muscle regeneration in mdx mice. For this purpose, the right masseter muscle of 100 days old mdx and healthy mice was paralyzed by a single specific intramuscular injection of BTX-A. After 21 days, right and left masseter and temporal muscles as well as tongue muscle were carefully dissected, and gene and protein expression of caveolin-1, caveolin-3 and vascular endothelial growth factor (VEGF) were determined using quantitative RT-PCR and Western blot technique. Statistics were performed using Student's t-test and Mann Whitney U-test (significance level: P ≤ 0.05). After BTX-A injection, in both mice strains and for all three studied genes, no significant differences in mRNA amount could be detected between treated and untreated masseter muscles. A significant increase in caveolin-1, caveolin-3 and VEGF mRNA expression could only be found in the right temporal muscle of control mice compared to the left side. All three investigated proteins were more frequent to be found in dystrophic masseter muscle samples compared to the corresponding control samples, whereas significant decreased caveolin-3 protein levels could only be detected in the treated masseter versus untreated masseter muscle of controls. In contrast to previous conclusions, with this study it was not possible to prove a BTX-A-induced dystrophic phenotype in control animals, in which only the known decreases of caveolin-3 protein expression could be verified due to denervation. At the same time, however, gene and protein expression in dystrophic mice was not changed after BTX-A injection.


Asunto(s)
Toxinas Botulínicas Tipo A/farmacología , Caveolina 1/metabolismo , Caveolina 3/metabolismo , Músculo Masetero/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Animales , Caveolina 1/genética , Caveolina 3/genética , Distrofina/deficiencia , Femenino , Masculino , Músculo Masetero/metabolismo , Ratones Endogámicos C57BL , Ratones Endogámicos mdx , ARN Mensajero/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética
5.
Eur J Intern Med ; 31: 20-4, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27053291

RESUMEN

BACKGROUND: Patients with nonspecific complaints (NSC) such as generalized weakness present frequently to acute care settings. These patients are at risk of adverse health outcomes. The aim of our study was to test the hypothesis whether D-dimers are predictive for 30-day mortality in patients with NSCs. METHODS: Delayed type cross-sectional diagnostic study with a 30-day follow-up period, registered with ClinicalTrials.gov (NCT00920491). This study took place in 2 EDs in Northwestern Switzerland. Patients were enrolled in the study if they were over 18years of age, gave informed consent, and if they presented with NSCs such as generalized weakness. D-dimer levels were determined at ED presentation. RESULTS: The final study population consisted of 524 patients. Median age was 82years (IQR=75 to 87years); 40.5% were men. There were 489 survivors and 35 non-survivors at 30-day follow-up. Twenty-one (60%) of the non-survivors were males. D-dimer levels were significantly higher in non-survivors than in survivors (p<0.001). Univariate Cox regression models for D-dimer resulted in a C-index of 0.77 for prediction of mortality. A model including sex, age, Katz ADL and D-dimer in a multivariate Cox regression lead to a C-Index of 0.80. CONCLUSION: D-dimer testing might be an effective risk stratification tool in patients with NSC by helping to identify patients at low risk of short-term mortality with a sensitivity of 0.97 and a negative likelihood ratio of 0.121. The use of D-dimers for risk stratification in patients with NSC should be confirmed with prospective studies.


Asunto(s)
Productos de Degradación de Fibrina-Fibrinógeno/análisis , Mortalidad , Debilidad Muscular/diagnóstico , Medición de Riesgo/métodos , Triaje/métodos , Anciano , Anciano de 80 o más Años , Biomarcadores/análisis , Estudios de Cohortes , Estudios Transversales , Servicio de Urgencia en Hospital , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Análisis Multivariante , Debilidad Muscular/etiología , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Índice de Severidad de la Enfermedad , Suiza/epidemiología
6.
Virchows Arch ; 446(4): 360-8, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15756591

RESUMEN

During pregnancy, the placenta produces a variety of proteins that are responsible for the establishment of the foeto-maternal tolerance and circulation. The aim of this study was to investigate the expression of glycodelin A (formerly named PP14) in decidual tissue of placentas with intrauterine growth restriction (IUGR), preeclamptic patients, hemolysis, elevated liver, low-platelet (HELLP) patients and normal decidual tissue. Slides of paraffin-embedded decidual tissue of patients with IUGR, preeclamptic patients, HELLP patients and normal-term placentas were incubated with either polyclonal or monoclonal antibodies against glycodelin A. Staining reaction was performed with the ABC reagent. Intensity of immunohistochemical reaction on the slides was analysed using a semi-quantitative score. In addition, expression of glycodelin mRNA was analysed by in situ hybridisation. Expression of glycodelin A was significantly reduced in decidual cells of placentas with IUGR and HELLP, as investigated with both monoclonal and polyclonal antibodies and in situ hybridisation. However, preeclamptic decidual tissue showed no significantly different expression of intensity of glycodelin mRNA compared with normal placental tissue controls. A reduced expression of glycodelin A by decidual cells seems to be related to IUGR and HELLP. Therefore, glycodelin A might play an important role in the pathogeneses of these diseases.


Asunto(s)
Decidua/metabolismo , Retardo del Crecimiento Fetal/metabolismo , Glicoproteínas/metabolismo , Síndrome HELLP/metabolismo , Preeclampsia/metabolismo , Proteínas Gestacionales/metabolismo , Adulto , Biomarcadores/metabolismo , Recuento de Células , Decidua/patología , Femenino , Retardo del Crecimiento Fetal/patología , Glicodelina , Glicoproteínas/genética , Síndrome HELLP/patología , Humanos , Procesamiento de Imagen Asistido por Computador , Técnicas para Inmunoenzimas , Hibridación in Situ , Preeclampsia/patología , Embarazo , Proteínas Gestacionales/genética , ARN Mensajero/metabolismo
7.
J Econ Entomol ; 98(2): 342-9, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15889722

RESUMEN

Lycoriella mali Fitch (Diptera: Sciaridae) infests mushroom crops early in the crop cycle. Recent observations in mushroom houses indicated a difference in emergence time and size of adult L. mali developing on various strains of commercial mushrooms. Samples of adult flies from isolated mushroom houses growing Portabella mushrooms were significantly heavier then those from oyster mushroom houses, whereas flies from shiitake mushroom houses were lightest in weight. Flies collected from isolated Portabella mushroom houses were reared on four strains and species of Agaricus and Pleurotus mushrooms. After the adults emerged, females were weighed, mated, and allowed to oviposit. The number of eggs laid increased as the weight of the female increased. Flies collected from isolated Portabella mushroom houses were reared on eight strains and species of mushrooms. Flies were reared for four generations on each host mushroom mycelium then switched to different host mushrooms. Overall, the hybrid strain of Agaricus bisporus (Lange) Imbach (Agaricales: Agaricomycetideae) was the most favorable host for L. mali, whereas the wild strain of A. bisporus was the least favorable host. Mushroom hosts influence developmental time, survivorship, weight, and reproduction of L. mali.


Asunto(s)
Agaricales , Dípteros/crecimiento & desarrollo , Estadios del Ciclo de Vida , Agaricus , Animales , Femenino , Interacciones Huésped-Parásitos , Masculino , Pleurotus , Especificidad de la Especie
8.
Urologe A ; 54(6): 811-8, 2015 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-25503897

RESUMEN

BACKGROUND: Several tyrosine kinase inhibitors (TKI) are used in the treatment of metastasized renal cell carcinoma (mRCC). This article presents a feasibility study for the measurement of plasma levels of sunitinib, sorafenib and pazopanib using liquid chromatography tandem mass spectrometry (LC-MS/MS). METHODS: A total of 23 patients suffering from mRCC under treatment with sunitinib (n=16), sorafenib (n=3) and pazopanib (n=4) were included. Plasma samples (100 µl) were separated by liquid chromatographic analysis and the plasma levels of the TKIs determined by tandem mass spectrometry. RESULTS: The plasma levels of sunitinib, sorafenib and pazopanib were measurable and the results reproducible. During storage of the plasma samples for 1 week at 4°C no significant decrease of the initial concentration was found. The highest plasma levels detected were 99 ng/ml for sunitinib, 9.8 µg/ml for sorafenib and 63 µg/ml for pazopanib. We could show variability in plasma levels according to changes in dosage of TKIs or during treatment-free intervals. CONCLUSION: Measurement of TKI plasma levels using LC-MS/MS is feasible. Further clinical studies have to be conducted to examine if there are any threshold levels for the incidence of adverse events or response to treatment.


Asunto(s)
Carcinoma de Células Renales/sangre , Carcinoma de Células Renales/secundario , Indoles/sangre , Neoplasias Renales/sangre , Niacinamida/análogos & derivados , Compuestos de Fenilurea/sangre , Pirimidinas/sangre , Pirroles/sangre , Sulfonamidas/sangre , Anciano , Anciano de 80 o más Años , Antineoplásicos/sangre , Carcinoma de Células Renales/tratamiento farmacológico , Monitoreo de Drogas/métodos , Estudios de Factibilidad , Femenino , Humanos , Indazoles , Indoles/uso terapéutico , Neoplasias Renales/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Niacinamida/sangre , Niacinamida/uso terapéutico , Compuestos de Fenilurea/uso terapéutico , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Pirimidinas/uso terapéutico , Pirroles/uso terapéutico , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Sorafenib , Sulfonamidas/uso terapéutico , Sunitinib
9.
Eur J Clin Nutr ; 69(3): 329-36, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25335442

RESUMEN

BACKGROUND/OBJECTIVES: New methods to measure visceral adipose tissue (VAT) by dual-energy X-ray absorptiometry (DXA) may help discern sex, race and phenotype differences in the role of VAT in cardiometabolic risk. This study was designed (1) to compare relationships of DXA-VAT, anthropometric and body composition variables with cardiometabolic risk factors in obese women; (2) to determine which variables most robustly predict impaired glucose tolerance (IGT) and metabolic syndrome (MetSx); and (3) to determine thresholds for DXA-VAT by race. SUBJECTS/METHODS: VAT mass (g) and volume (cm(3)) were measured in 229 obese (body mass index (BMI), 30-49.9) women aged 21-69 years of European-American (EA=123) and African-American (AA=106) descent using the CoreScan algorithm on a Lunar iDXA scanner. Linear regression modeling and areas under the curve (AUC of ROC (receiver operating characteristic) curves) compared relationships with cardiometabolic risk. Bootstrapping with LASSO (least absolute shrinkage and selection operator) regression modeling determined thresholds and predictors of IGT and MetSx. RESULTS: DXA-VAT explained more of the variance in triglycerides, blood pressure, glucose and homeostatic model assessment-insulin resistance (HOMA-IR) compared with anthropometric and other body composition variables. DXA-VAT also had the highest AUC for IGT (0.767) and MetSx (0.749). Including race as a variable and the interaction between VAT and race in modeling did not significantly change the results. Thresholds at which the probability of developing IGT or MetSx was⩾50% were determined separately for AA women (IGT: 2120 cm(3); MetSx: 1320 cm(3)) and EA women (IGT: 2550 cm(3); MetSx: 1713 cm(3)). The odds for IGT or MetSx were fourfold greater with each standard deviation increase in DXA-VAT. CONCLUSIONS: DXA-VAT provides robust clinical information regarding cardiometabolic risk in AA and EA obese women and offers potential utility in the risk reduction interventions.


Asunto(s)
Negro o Afroamericano , Composición Corporal , Intolerancia a la Glucosa/etiología , Grasa Intraabdominal/metabolismo , Síndrome Metabólico/etiología , Obesidad/complicaciones , Población Blanca , Absorciometría de Fotón/métodos , Adulto , Antropometría/métodos , Enfermedades Cardiovasculares/etnología , Enfermedades Cardiovasculares/etiología , Femenino , Intolerancia a la Glucosa/etnología , Intolerancia a la Glucosa/metabolismo , Humanos , Síndrome Metabólico/etnología , Obesidad/etnología , Obesidad/metabolismo , Factores de Riesgo
10.
J Mol Endocrinol ; 23(1): 57-66, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10425447

RESUMEN

In the present study we demonstrate for the first time the expression of glycodelin mRNA in the female and male genital tracts of rats using non-radioactive in situ hybridisation. Glycodelin fragment 1 (+41 to +141) shares 100% homology with the human gene sequence. In the ovary, glycodelin mRNA was restricted to granulosa cells. In the uterus, glycodelin mRNA was expressed in all epithelial cells of the endometrium. In the male reproductive tract, glycodelin mRNA was distributed in all epithelial cells of the epididymis, the prostate and the seminal vesicle. However, in the testis, glycodelin mRNA was predominantly found in spermatogonia and in spermatocytes of the seminiferous epithelium. The expression in several reproductive organs of rats offers an excellent tool to study further the physiological role of glycodelin, which is so far thought to act as an immunosuppressive factor.


Asunto(s)
Genitales Femeninos/metabolismo , Genitales Masculinos/metabolismo , Glicoproteínas/genética , Proteínas Gestacionales/genética , ARN Mensajero/genética , Animales , Northern Blotting , Femenino , Expresión Génica , Glicodelina , Humanos , Hibridación in Situ , Masculino , Embarazo , ARN/genética , ARN/metabolismo , Sondas ARN , ARN Mensajero/metabolismo , Ratas , Ratas Endogámicas Lew , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Distribución Tisular
11.
J Mol Endocrinol ; 24(1): 135-44, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10657005

RESUMEN

In the endometrium two enzymes are known to convert estradiol to its inactive metabolite estrone: microsomal 17beta-hydroxysteroid dehydrogenase type 2 (17beta-HSD2) and peroxisomal 17beta-HSD4. In order to elucidate the particular function of each of these two different enzymes, the human endometrial epithelial cell lines HEC-1-A and RL95-2 were examined with respect to the expression of 17betaHSD isozymes. They were compared with human endometrium in vivo. Non-radioactive in situ hybridization revealed both enzymes in glandular epithelial cells of human endometrium. The two cell lines were screened for mRNA expression of 17beta-HSD 1-4 by RT-PCR and Northern blot. 17beta-HSD2 and 4 could be detected by either method, 17beta-HSD1 only by RT-PCR, 17beta-HSD3 not at all. Both cell lines were proven to have no receptor for progesterone which is known as a physiological inducer of several 17beta-HSD isozymes. To study the regulation of 17beta-HSD2 and 17betaHSD4, the concentration of fetal calf serum in the cell culture media was reduced stepwise to 0.3% by dilution with a defined serum replacement. This treatment led to an inhibition of 17beta-HSD2 mRNA expression and an increase in the mRNA expression of 17beta-HSD4. Concomitantly, distinct morphological changes were observed, such as a decrease in the number and length of microvilli and a decrease in the formation of domes on top of the monolayers. The endometrial epithelial cell lines HEC-1-A and RL95-2 represent a suitable in vitro model for further studies of the differential expression of the major endometrial HSD isozymes, independent of the effect of progesterone.


Asunto(s)
17-Hidroxiesteroide Deshidrogenasas/metabolismo , Endometrio/enzimología , Isoenzimas/metabolismo , 17-Hidroxiesteroide Deshidrogenasas/genética , Adulto , Secuencia de Bases , Northern Blotting , Línea Celular , Cartilla de ADN , Endometrio/citología , Femenino , Colorantes Fluorescentes , Humanos , Hibridación in Situ , Isoenzimas/genética , ARN Mensajero/genética , Ensayo de Unión Radioligante , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
12.
Psychol Bull ; 127(5): 673-97, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11548973

RESUMEN

The dynamic nature of the predictor-criterion relationship has long been a concern in psychology, especially with regard to the deterioration of validity over time. The authors examine P. L. Ackerman's ( 1987, 1988) hypothesized relationships between different types of predictors and criteria over time using data from previous longitudinal studies. Expert ratings categorized predictors and criteria according to P. L. Ackerman's model. Regression results support the predicted negative curvilinear relationship between cognitive ability and consistent and inconsistent task performance but do not support the predicted relationships between perceptual speed ability and psychomotor ability and consistent and inconsistent task performance. Deterioration of validity was more ubiquitous than has been suggested previously, and the pervasive form of deterioration was cubic with a negative trend. Findings are discussed in the context of catastrophe-chaos models.


Asunto(s)
Psicometría , Desempeño Psicomotor , Tiempo de Reacción , Humanos , Modelos Estadísticos , Dinámicas no Lineales , Reproducibilidad de los Resultados
13.
Naunyn Schmiedebergs Arch Pharmacol ; 368(6): 463-9, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14618298

RESUMEN

A promising development in tumor therapy is the application of non-toxic prodrugs from which the active cytostatic is released by endogenous enzymes such as beta-glucuronidase (beta-gluc). Regulation of beta-gluc expression is one crucial factor modulating bioactivation of prodrugs. Recent experiments in rats indicate regulation of beta-gluc activity by the calcium channel blocker verapamil. To further explore this phenomenon, we investigated the effect of verapamil on beta-gluc enzyme activity, protein (western blot) and mRNA expression (RT-PCR) as well as the underlying mechanisms (effects of verapamil metabolites; promoter activity) in the human hepatoma cell line HepG2. Treatment of HepG2 cells with verapamil revealed down-regulation of beta-gluc activity, protein, and mRNA level down to 50% of the control with EC(50) values of 25 microM. Effects were similar for both enantiomers. Moreover, it was demonstrated that reduced promoter activity contributes to the observed effects. In summary, our data demonstrate regulation of human beta-glucuronidase expression by verapamil. Based on our findings we hypothesize that coadministration of verapamil may effect cleavage of glucuronides by beta-glucuronidase.


Asunto(s)
Glucuronidasa/biosíntesis , Himecromona/análogos & derivados , ARN Mensajero/biosíntesis , Verapamilo/farmacología , Western Blotting , Bloqueadores de los Canales de Calcio/química , Bloqueadores de los Canales de Calcio/metabolismo , Bloqueadores de los Canales de Calcio/farmacología , Carcinoma Hepatocelular/enzimología , Carcinoma Hepatocelular/genética , Línea Celular Tumoral , Regulación hacia Abajo/efectos de los fármacos , Genes Reporteros , Glucuronidasa/genética , Glucuronidasa/metabolismo , Gliceraldehído-3-Fosfato Deshidrogenasas/biosíntesis , Humanos , Himecromona/metabolismo , Neoplasias Hepáticas/enzimología , Neoplasias Hepáticas/genética , Regiones Promotoras Genéticas , Estereoisomerismo , Factores de Tiempo , Transfección , Verapamilo/análogos & derivados , Verapamilo/metabolismo
14.
Clin Neuropathol ; 23(5): 223-31, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15581025

RESUMEN

OBJECTIVE: Dysembryoplastic neuroepithelial tumors (DNT) are relatively benign brain lesions that often cause medically intractable epilepsy. There is mounting evidence that multidrug transporters such as P-glycoprotein (P-gp) or multidrug resistance-associated proteins (MRP) play an important role in the development of resistance to antiepileptic drugs (AED). MATERIAL AND METHODS: In the present study, we examined the expression of several multidrug transporters in 14 cases of DNT. The peritumoral brain tissue as well as 9 cases of arteriovenous malformations (AVM) served as controls. P-gp, MRP2, MRP5 and breast cancer resistance protein (BCRP) expression was evaluated qualitatively and quantitatively using immunohistochemistry. RESULTS: All transporters were overexpressed quantitatively in DNT, but each revealed a different labeling pattern. P-gp and BCRP were predominantly located in the endothelium of brain vessels. MRP5 was detected primarily in endothelial cells, but notably also in neurons. The expression of P-gp, MRP2 and MRP5 was low in AVM, whereas BCRP demonstrated strong staining. Examination of MDR1 gene polymorphisms revealed no correlation with P-gp expression whereas the MRP2 exon 10 G1249A polymorphism was associated with different MRP2 labelling. CONCLUSIONS: Our results show that multidrug transporters are overexpressed in DNT. This finding supports the view that several of these transport proteins may play an important role in the mechanisms of drug resistance in epileptic brain tissue.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Epilepsia/etiología , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/biosíntesis , Neoplasias Neuroepiteliales/metabolismo , Adolescente , Adulto , Neoplasias Encefálicas/irrigación sanguínea , Neoplasias Encefálicas/complicaciones , Niño , Resistencia a Medicamentos/fisiología , Células Endoteliales/metabolismo , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Inmunohistoquímica , Malformaciones Arteriovenosas Intracraneales/metabolismo , Masculino , Persona de Mediana Edad , Neoplasias Neuroepiteliales/irrigación sanguínea , Neoplasias Neuroepiteliales/complicaciones , Polimorfismo Genético , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
15.
Water Res ; 36(8): 2133-9, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12092588

RESUMEN

Toxic effects and microcystin content from various extracts of a Planktothrix agardhii bloom and two different strains of Planktothrix agardhii, HUB 076, and NIVA 34 were investigated. Extracts were obtained with solvents of different polarity such as hexane, dichloromethane, methanol, and water. Additionally, different pre-treatments were used to break the cells before extraction. Acute toxicity was determined with the fairy shrimp Thamnocephalus platyurus, subchronic effects were detected in embryos and larvae of the zebrafish Danio rerio. The extracts affected the test species to a different extent. Effects were severe in polar extracts (water and methanol) of all strains tested. Although the strain NIVA 34 did not contain any microcystins, aqueous extracts of this strain showed the highest acute toxicity to the crustacean species tested (LC50= 0.08 mg ml(-1)). In contrast aqueous extracts of the Planktothrix bloom containing high amounts of microcystins were less acutely toxic (LC50 = 0.46 mg ml(-1)). Our results indicate the existence of further toxic metabolites in different Plankorothrix agardhii strains.


Asunto(s)
Cianobacterias/patogenicidad , Eutrofización , Péptidos Cíclicos/toxicidad , Animales , Decápodos , Dosificación Letal Mediana , Microcistinas
16.
Int J Oral Maxillofac Implants ; 13(5): 639-46, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9796147

RESUMEN

In this clinical study, a bioabsorbable membrane (Biofix) and two augmentation membranes made of expanded polytetrafluoroethylene (Gore-Tex) were tested for their osteopromotive potential. Forty-six implants were augmented with Gore-Tex membranes, 45 implants with titanium-reinforced Gore-Tex membranes, and 38 peri-implant defects with a resorbable polyglycolid membrane (Biofix). Autogenous bone (n = 85) and bovine bone matrix (Bio-Oss, n = 16) were used as filling materials beneath membranes. The results showed that bone repair is significantly improved by the use of membrane techniques. The average rate of bone regeneration with non-resorbable membranes was 84% (GTAM) and 81% (TR-GTAM). The use of Biofix membranes resulted in an average bone gain of 60%. The differences in efficacy established for the three types of membranes were found to be statistically significant (P < .001). Barrier membranes represent a valid technique for the treatment of peri-implant defects. Clinical and histologic results showed that Bio-Oss is an osteoconductive scaffold that promotes new bone formation.


Asunto(s)
Pérdida de Hueso Alveolar/cirugía , Regeneración Ósea , Implantes Dentales/efectos adversos , Regeneración Tisular Guiada Periodontal/métodos , Membranas Artificiales , Implantes Absorbibles , Adulto , Anciano , Pérdida de Hueso Alveolar/etiología , Animales , Sustitutos de Huesos , Trasplante Óseo , Bovinos , Implantación Dental Endoósea , Humanos , Persona de Mediana Edad , Minerales , Ácido Poliglicólico , Politetrafluoroetileno , Resultado del Tratamiento
17.
J Air Waste Manag Assoc ; 45(7): 547-55, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7634126

RESUMEN

The release rates of volatile organic compounds (VOC) as fugitive emissions from offset printing are difficult to quantify, and the compositions are usually not known. Tests were conducted at three offset printing shops that varied in size and by process. In each case, the building shell served as the test "enclosure," and air flow and concentration measurements were made at each air entry and exit point. Emission rates and VOC composition were determined during production for (1) a small shop containing three sheetfed presses and two spirit duplicators (36,700 sheets, 47,240 envelopes and letterheads), (2) a medium-size industrial in-house shop with two webfed and three sheetfed presses, and one spirit duplicator (315,130 total sheets), and (3) one print room of a large commercial concern containing three webfed, heatset operations (1.16 x 10(6) ft) served by catalytic air pollution control devices. Each test consisted of 12 one-hour periods over two days. Air samples were collected simultaneously during each period at 7-14 specified locations within each space. The samples were analyzed by gas chromatography (GC) for total VOC and for 13-19 individual organics. Samples of solvents used at each shop were also analyzed by GC. Average VOC emission rates were 4.7-6.1 kg/day for the small sheetfed printing shop, 0.4-0.9 kg/day for the industrial shop, and 79-82 kg/day for the commercial print room. Emission compositions were similar and included benzene, toluene, xylenes, ethylbenzene, and hexane. Comparison of the emission rates with mass balance estimates based on solvent usage and composition were quite consistent.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Impresión , Cromatografía de Gases
18.
Int J Periodontics Restorative Dent ; 20(3): 255-67, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11203567

RESUMEN

The aim of the present study was to investigate clinical and radiographic data of patients treated with implants in the posterior maxilla in combination with sinus augmentation. Study parameters included Periotest values, radiographic analysis, and survival/success rates up to 5 years. Clinical and radiographic criteria resulted in a success rate of 92.7% for sinus implants. Radiographically, the sinus implants showed a mean coronal bone loss of 0.5 mm at 6 months and 1.2 mm at 48 months. The results showed stable periimplant parameters for sinus implants during the observation period of 5 years. The success rates showed no significant differences regarding different implant-supported treatment options for the posterior maxillary region.


Asunto(s)
Implantes Dentales , Prótesis Dental de Soporte Implantado , Seno Maxilar/cirugía , Procedimientos Quirúrgicos Preprotésicos Orales , Adulto , Sustitutos de Huesos , Implantación Dental Endoósea , Femenino , Humanos , Masculino , Persona de Mediana Edad , Minerales , Diente Molar , Oseointegración , Estudios Retrospectivos , Tasa de Supervivencia
19.
Int J Comput Dent ; 3(4): 243-58, 2000 Oct.
Artículo en Inglés, Alemán | MEDLINE | ID: mdl-11410972

RESUMEN

Since the introduction of crown software for Cerec, it has been possible to produce full-ceramic crown restorations. Despite the excellent material quality of industrially made ceramic blocks and the good clinical long-term success of these ceramics in inlay- and onlay preparations, extended preparation with high loss of dental tissue is incident to crown restorations, which may endanger the vitality of the respective tooth. The aim of this experimental study was to determine the residual dentin thickness after preparation of an extended circular shoulder in the molar and premolar region. On extracted human molars and premolars, 1.2-mm-wide circular shoulders with rounded inner edges were prepared, and the thickness of the residual dentin wall was measured under a microscope. Using this preparation method, it was found that only the group of maxillary molars showed an average residual dentin thickness of more than 0.7 mm.


Asunto(s)
Coronas , Dentina , Preparación Protodóncica del Diente , Diente Premolar , Cerámica , Diseño Asistido por Computadora , Porcelana Dental , Diseño de Prótesis Dental , Dentina/anatomía & histología , Humanos , Diente Molar , Estadísticas no Paramétricas
20.
Z Orthop Unfall ; 152(5): 498-503, 2014 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-25313704

RESUMEN

BACKGROUND: Minimally invasive treatment of diaphyseal femur fractures (DFF) with closed reduction and intramedullary nailing is a well established procedure. However, a femoral malrotation after intramedullary nailing is considered to be a substantial problem. Studies have described femoral malrotation (FMR) in 17-35 % after this procedure. Computed tomography (CT) of both femora is accepted as an objective, reproducible measurement method to determine a postoperative femoral malrotation. An anatomic reposition of the centreline of the femur remains of high importance since a malrotation > 15° can lead to a significant limitation of the range of motion (ROM) and to clinical symptomatic constraints. PATIENTS/MATERIAL AND METHODS: Between July 2007 and December 2011 patients with unilateral DFF were treated with closed reduction and intramedullary nailing. Exclusion criteria were defined as bilateral or prior treatment for femoral fractures, open epihyseal plate or pregnancy. In all cases a postoperative CT scan of the femora was conducted to analyse a femoral malrotation. The indication for a correction was posed in cases of a malrotation > 15°. The data were not randomised and evaluated retrospectively. RESULTS AND CONCLUSION: In total 94 patients with unilateral DFF were included. 21 female and 73 male with an average age of 33.15 ± 14.04 years (range 14-94). In the postoperative CT scan an average FMR of 11.58 ± 9.41° (range 0-44°) was determined. In 15 cases (15.95 %), 10 male (13.7 %) and 5 female (23.81 %) a FMR > 15° (average: 23.66 ± 5.74°) was noticed. A subsequent surgery with a correction in average of 17.53 ± 6.83° was performed. After the correction the malrotation averaged 6.07 ± 5.61°. The results support the existing data that the treatment of DFF with closed reduction and intramedullary nailing may lead to a significant femoral malrotation despite a precise intraoperative monitoring. The data demonstrate that nearly 15 % of all patients appear after closed reduction and intramedullary nailing with a femoral malrotation greater than 15°. A routinely utilised postoperative CT scan provides additional information to discover an occult malrotation. CONCLUSION: In spite of diligent attendance to the femoral torsion intraoperatively in DFF a significant femoral malrotation may result after closed reduction and intramedullary nailing. To prevent a limitation of ROM and clinical constraints a routinely performed postoperative CT scan with a adequate surgical correction is recommended.


Asunto(s)
Desviación Ósea/etiología , Fracturas del Fémur/diagnóstico , Fracturas del Fémur/cirugía , Fémur/anomalías , Fémur/cirugía , Fijación Intramedular de Fracturas/efectos adversos , Osteotomía/efectos adversos , Adulto , Desviación Ósea/diagnóstico , Desviación Ósea/prevención & control , Terapia Combinada/efectos adversos , Femenino , Fracturas del Fémur/complicaciones , Humanos , Estudios Longitudinales , Masculino , Estudios Retrospectivos , Resultado del Tratamiento
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