30 resultados para Winthrop Normal and Industrial College
Resumo:
Type 2 diabetes and obesity are increasing worldwide and linked to periodontitis, a chronic disease which is characterized by the irreversible destruction of the tooth-supporting tissues, that is, periodontium. The mechanisms underlying the association of diabetes mellitus and obesity with periodontal destruction and compromised periodontal healing are not well understood, but decreased plasma levels of adiponectin, as found in diabetic and obese individuals, might be a critical mechanistic link. The aim of this in vitro study was to examine the effects of adiponectin on periodontal ligament (PDL) cells under normal and regenerative conditions, and to study the regulation of adiponectin and its receptors in these cells. Adiponectin stimulated significantly the expression of growth factors and extracellular matrix, proliferation, and in vitro wound healing, reduced significantly the constitutive tumor necrosis factor-α expression, and caused a significant upregulation of its own expression. The beneficial actions of enamel matrix derivative on a number of PDL cell functions critical for periodontal regeneration were partially enhanced by adiponectin. The periodontopathogen Porphyromonas gingivalis inhibited the adiponectin expression and stimulated the expression of its receptors. In conclusion, reduced levels of adiponectin, as found in type 2 diabetes and obesity, may compromise periodontal health and healing.
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Glucagon-like-peptide-1 (GLP1) analogs may induce thyroid or pancreatic diseases in animals, raising questions about their use in diabetic patients. There is, however, controversy regarding expression of GLP1 receptors (GLP1R) in human normal and diseased thyroid and pancreas. Here, 221 human thyroid and pancreas samples were analyzed for GLP1R immunohistochemistry and compared with quantitative in vitro GLP1R autoradiography. Neither normal nor hyperplastic human thyroids containing parafollicular C cells express GLP1R with either method. Papillary thyroid cancer do not, and medullary thyroid carcinomas rarely express GLP1R. Insulin- and somatostatin-producing cells in the normal pancreas express a high density of GLP1R, whereas acinar cells express them in low amounts. Ductal epithelial cells do not express GLP1R. All benign insulinomas express high densities of GLP1R, whereas malignant insulinomas rarely express them. All ductal pancreatic carcinomas are GLP1R negative, whereas 6/20 PanIN 1/2 and 0/12 PanIN 3 express GLP1R. Therefore, normal thyroid, including normal and hyperplastic C cells, or papillary thyroid cancer are not targets for GLP1 analogs in humans. Conversely, all pancreatic insulin- and somatostatin-producing cells are physiological GLP1 targets, as well as most acini. As normal ductal epithelial cells or PanIN 3 or ductal pancreatic carcinomas do not express GLP1R, it seems unlikely that GLP1R is related to neoplastic transformation in pancreas. GLP1R-positive medullary thyroid carcinomas and all benign insulinomas are candidates for in vivo GLP1R targeting.Modern Pathology advance online publication, 12 September 2014; doi:10.1038/modpathol.2014.113.
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The main purpose of this study was to evaluate the effect that mechanical stresses acting under the slipping driving wheels of agricultural equipment have on the soil’s pore system and water flow process (surface runoff generation during extreme event). The field experiment simulated low slip (1%) and high slip (27%) on a clay loam. The stress on the soil surface and changes in the amounts of water flowing from macropores were simulated using the Tires/tracks And Soil Compaction (TASC) tool and the MACRO model, respectively. Taking a 65 kW tractor on a clay loam as a reference, results showed that an increase in slip of the rear wheels from 1% to 27% caused normal stress to increase from 90.6 kPa to 104.4 kPa at the topsoil level, and the maximum shear contact stress to rise drastically from 6.0 kPa to 61.6 kPa. At 27% slip, topsoil was sheared and displaced over a distance of 0.35 m. Excessive normal and shear stress values with high slip caused severe reductions of the soil’s macroporosity, saturated hydraulic conductivity, and water quantities flowing from topsoil macropores. Assuming that, under conditions of intense rainfall on sloping land, a loss in vertical water flow would mean an increase in surface runoff, we calculated that a rainfall intensity of 100 mm h-1 and a rainfall duration of 1 h would increase the runoff coefficient to 0.79 at low slip and to 1.00 at high slip, indicating that 100% of rainwater would be transformed into surface runoff at high slip. We expect that these effects have a significant impact on soil erosion and floods in steeper terrain (slope > 15°) and across larger surface areas (> 16 m2) than those included in our study.
Resumo:
Particulate matter (PM) pollution is a leading cause of premature death, particularly in those with pre-existing lung disease. A causative link between particle properties and adverse health effects remains unestablished mainly due to complex and variable physico-chemical PM parameters. Controlled laboratory experiments are required. Generating atmospherically realistic Aerosols and performing cell-exposure studies at relevant particle-doses are challenging. Here we examine gasoline-exhaust particle toxicity from a Euro-5 passenger car in a uniquely realistic exposure scenario, combining a smog chamber simulating atmospheric ageing, an aerosol enrichment System varying particle number concentration independent of particle chemistry, and an aerosol Deposition chamber physiologically delivering particles on air-liquid interface (ALI) cultures reproducing normal and susceptible health status. Gasoline-exhaust is an important PM source with largely unknown health effects. We investigated acute responses of fully-differentiated normal, distressed (antibiotics treated) normal, and cystic fibrosis human bronchial epithelia (HBE), and a proliferating, single-cell type bronchial epithelial cell-line (BEAS-2B). We show that a single, short-term exposure to realistic doses of atmospherically-aged gasoline-exhaust particles impairs epithelial key-defence mechanisms, rendering it more vulnerable to subsequent hazards. We establish dose-response curves at realistic particle-concentration levels. Significant differences between cell models suggest the use of fully differentiated HBE is most appropriate in future toxicity studies.
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Microbeam radiation therapy (MRT) is a new form of preclinical radiotherapy using quasi-parallel arrays of synchrotron X-ray microbeams. While the deposition of several hundred Grays in the microbeam paths, the normal brain tissues presents a high tolerance which is accompanied by the permanence of apparently normal vessels. Conversely, the efficiency of MRT on tumor growth control is thought to be related to a preferential damaging of tumor blood vessels. The high resistance of the healthy vascular network was demonstrated in different animal models by in vivo biphoton microscopy, magnetic resonance imaging, and histological studies. While a transient increase in permeability was shown, the structure of the vessels remained intact. The use of a chick chorioallantoic membrane at different stages of development showed that the damages induced by microbeams depend on vessel maturation. In vivo and ultrastructural observations showed negligible effects of microbeams on the mature vasculature at late stages of development; nevertheless a complete destruction of the immature capillary plexus was found in the microbeam paths. The use of MRT in rodent models revealed a preferential effect on tumor vessels. Although no major modification was observed in the vasculature of normal brain tissue, tumors showed a denudation of capillaries accompanied by transient increased permeability followed by reduced tumor perfusion and finally, a decrease in number of tumor vessels. Thus, MRT is a very promising treatment strategy with pronounced tumor control effects most likely based on the anti-vascular effects of MRT.
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An accurate and efficient determination of the highly toxic Cr(VI) in solid materials is important to determine the total Cr(VI) inventory of contaminated sites and the Cr(VI) release potential from such sites into the environment. Most commonly, total Cr(VI) is extracted from solid materials following a hot alkaline extraction procedure (US EPA method 3060A) where a complete release of water-extractable and sparingly soluble Cr(VI) phase is achieved. This work presents an evaluation of matrix effects that may occur during the hot alkaline extraction and in the determination of the total Cr(VI) inventory of variably composed contaminated soils and industrial materials (cement, fly ash) and is compared to water-extractable Cr(VI) results. Method validation including multiple extractions and matrix spiking along with chemical and mineralogical characterization showed satisfying results for total Cr(VI) contents for most of the tested materials. However, unreliable results were obtained by applying method 3060A to anoxic soils due to the degradation of organic material and/or reactions with Fe2+-bearing mineral phases. In addition, in certain samples discrepant spike recoveries have to be also attributed to sample heterogeneity. Separation of possible extracted Cr(III) by applying cation-exchange cartridges prior to solution analysis further shows that under the hot alkaline extraction conditions only Cr(VI) is present in solution in measurable amounts, whereas Cr(III) gets precipitated as amorphous Cr(OH)3(am). It is concluded that prior to routine application of method 3060A to a new material type, spiking tests are recommended for the identification of matrix effects. In addition, the mass of extracted solid material should to be well adjusted to the heterogeneity of the Cr(VI) distribution in the material in question.
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The purpose of this study was to simulate pulmonary emboli (PE) and image quality at low tube energy and reduced contrast material volume in normal-dose pulmonary CT angiography (CTA) images and to analyze the diagnostic accuracy with normal- and low-dose pulmonary CTA.
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Neurodegenerative diseases affect the cerebellum of numerous dog breeds. Although subjective, magnetic resonance (MR) imaging has been used to detect cerebellar atrophy in these diseases, but there are few data available on the normal size range of the cerebellum relative to other brain regions. The purpose of this study was to determine whether the size of the cerebellum maintains a consistent ratio with other brain regions in different ages and breeds of normal dogs and to define a measurement that can be used to identify cerebellar atrophy on MR images. Images from 52 normal and 13 dogs with cerebellar degenerative diseases were obtained. Volume and mid-sagittal cross-sectional area of the forebrain, brainstem, and cerebellum were calculated for each normal dog and compared between different breeds and ages as absolute and relative values. The ratio of the cerebellum to total brain and of the brainstem to cerebellum mid-sagittal cross-sectional area was compared between normal and affected dogs and the sensitivity and specificity of these ratios at distinguishing normal from affected dogs was calculated. The percentage of the brain occupied by the cerebellum in diverse dog breeds between 1 and 5 years of age was not significantly different, and cerebellar size did not change with increasing age. Using a cut off of 89%, the ratio between the brainstem and cerebellum mid-sagittal cross-sectional area could be used successfully to differentiate affected from unaffected dogs with a sensitivity and specificity of 100%, making this ratio an effective tool for identifying cerebellar atrophy on MR images.
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AIMS: To compare morphometric parameters and diagnostic performance of the new Stratus Optical Coherence Tomograph (OCT) Disc mode and the Heidelberg Retina Tomograph (HRT); to evaluate OCT's accuracy in determining optic nerve head (ONH) borders. METHODS: Controls and patients with ocular hypertension, glaucoma-like discs, and glaucoma were imaged with OCT Disc mode, HRT II, and colour disc photography (DISC-PHOT). In a separate session, automatically depicted ONH shape and size in OCT were compared with DISC-PHOT, and disc borders adjusted manually where required. In a masked fashion, all print-outs and photographs were studied and discs classified as normal, borderline, and abnormal. The Cohen kappa method was then applied to test for agreement of classification. Bland-Altman analysis was used for comparison of disc measures. RESULTS: In all, 49 eyes were evaluated. Automated disc margin recognition failed in 53%. Misplaced margin points were more frequently found in myopic eyes, but only 31/187 were located in an area of peripapillary atrophy. Agreement of OCT with photography-based diagnosis was excellent in normally looking ONHs, but moderate in discs with large cups, where HRT performed better. OCT values were consistently larger than HRT values for disc and cup area. Compared with HRT, small rim areas and volumes tended to be minimized by OCT, and larger ones to be magnified. CONCLUSIONS: Stratus OCT Disc protocol performed overall well in differentiating between normal and glaucomatous ONHs. However, failure of disc border recognition was frequently observed, making manual correction necessary. ONH measures cannot be directly compared between HRT and OCT.
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INTRODUCTION: Recent findings suggest that articular cartilage contains mesenchymal progenitor cells. The aim of this study was to examine the distribution of stem cell markers (Notch-1, Stro-1 and VCAM-1) and of molecules that modulate progenitor differentiation (Notch-1 and Sox9) in normal adult human articular cartilage and in osteoarthritis (OA) cartilage. METHODS: Expression of the markers was analyzed by immunohistochemistry (IHC) and flow cytometry. Hoechst 33342 dye was used to identify and sort the cartilage side population (SP). Multilineage differentiation assays including chondrogenesis, osteogenesis and adipogenesis were performed on SP and non-SP (NSP) cells. RESULTS: A surprisingly high number (>45%) of cells were positive for Notch-1, Stro-1 and VCAM-1 throughout normal cartilage. Expression of these markers was higher in the superficial zone (SZ) of normal cartilage as compared to the middle zone (MZ) and deep zone (DZ). Non-fibrillated OA cartilage SZ showed reduced Notch-1 and Sox9 staining frequency, while Notch-1, Stro-1 and VCAM-1 positive cells were increased in the MZ. Most cells in OA clusters were positive for each molecule tested. The frequency of SP cells in cartilage was 0.14 +/- 0.05% and no difference was found between normal and OA. SP cells displayed chondrogenic and osteogenic but not adipogenic differentiation potential. CONCLUSIONS: These results show a surprisingly high number of cells that express putative progenitor cell markers in human cartilage. In contrast, the percentage of SP cells is much lower and within the range of expected stem cell frequency. Thus, markers such as Notch-1, Stro-1 or VCAM-1 may not be useful to identify progenitors in cartilage. Instead, their increased expression in OA cartilage implicates involvement in the abnormal cell activation and differentiation process characteristic of OA.
Resumo:
Cellular infiltrates are present already in early stages of chronic pancreatitis. The mechanisms responsible for their recruitment are unknown. Hence, we determined the differential expression of chemokine genes and their cellular sources in normal and affected pancreatic tissues.