318 research outputs found
Compressibility of titanosilicate melts
The effect of composition on the relaxed adiabatic bulk modulus (K0) of a range of alkali- and alkaline earth-titanosilicate [X 2 n/n+ TiSiO5 (X=Li, Na, K, Rb, Cs, Ca, Sr, Ba)] melts has been investigated. The relaxed bulk moduli of these melts have been measured using ultrasonic interferometric methods at frequencies of 3, 5 and 7 MHz in the temperature range of 950 to 1600°C (0.02 Pa s < s < 5 Pa s). The bulk moduli of these melts decrease with increasing cation size from Li to Cs and Ca to Ba, and with increasing temperature. The bulk moduli of the Li-, Na-, Ca- and Ba-bearing metasilicate melts decrease with the addition of both TiO2 and SiO2 whereas those of the K-, Rb- and Cs-bearing melts increase. Linear fits to the bulk modulus versus volume fraction of TiO2 do not converge to a common compressibility of the TiO2 component, indicating that the structural role of TiO2 in these melts is dependent on the identity of the cation. This proposition is supported by a number of other property data for these and related melt compositions including heat capacity and density, as well as structural inferences from X-ray absorption spectroscopy (XANES). The compositional dependence of the compressibility of the TiO2 component in these melts explains the difficulty incurred in previous attempts to incorporate TiO2 in calculation schemes for melt compressibility. The empirical relationship KV-4/3 for isostructural materials has been used to evaluate the compressibility-related structural changes occurring in these melts. The alkali metasilicate and disilicate melts are isostructural, independent of the cation. The addition of Ti to the metasilicate composition (i.e. X2TiSiO5), however, results in a series of melts which are not isostructural. The alkaline-earth metasilicate and disilicate compositions are not isostructural, but the addition of Ti to the metasilicate compositions (i.e. XTiSiO5) would appear, on the basis of modulus-volume systematics, to result in the melts becoming isostructural with respect to compressibility
Perfeccionismo no transtorno obsessivo-compulsivo e nos transtornos alimentares
OBJETIVO: Este estudo tem dois objetivos principais. Primeiro, avaliar as dimensões do perfeccionismo no transtorno obsessivo-compulsivo e nos transtornos alimentares em comparação com duas amostras controle: psiquiátrica (depressão/ansiedade) e não clínica. Segundo, avaliar se o perfeccionismo é um traço de personalidade especificamente relacionado com estas diferentes condições clínicas. MÉTODO: 39 pacientes com transtorno obsessivo-compulsivo, 24 com transtornos alimentares, 65 com um diagnóstico de depressão e/ou ansiedade (todos estes pacientes encontravam-se em regime de ambulatório) e 70 controles não clínicos completaram a versão portuguesa da Multidimensional Perfectionism Scale. RESULTADOS: Comparativamente à amostra não clínica, todas as amostras clínicas apresentaram níveis significativamente mais elevados na Multidimensional Perfectionism Scale total, no Perfeccionismo Auto-Orientado e no Perfeccionismo-Socialmente-Prescrito. Não houve diferenças estatisticamente significativas no Perfeccionismo-Auto-Orientado e na Multidimensional Perfectionism Scale total nas três amostras clínicas. No entanto, a amostra com transtornos alimentares apresentou níveis significativamente mais elevados de Perfeccionismo-Socialmente-Prescrito, comparativamente à transtornos alimentares e à amostra psiquiátrica (depressão/ansiedade). CONCLUSÃO: O perfeccionismo revelou estar associado a uma grande variedade de condições psicopatológicas. Contudo, as diferenças encontradas entre a amostra de transtornos alimentares, de transtorno obsessivo-compulsivo e a psiquiátrica no Perfeccionismo-Socialmente-Prescrito necessitam de investigação subsequente no sentido de clarificar a especificidade desta dimensão com os transtornos alimentares
Why should we screen for perinatal depression? Ten reasons to do it
In this paper we review some of the best available evidence to argue that screening for perinatal depression should be systematically conducted since pregnancy. Our view is organized in ten topics: (1) perinatal depression high prevalence; (2) its potential negative consequences, including maternal, conjugal, foetal, infantile, and child effects; (3) its under-detection and treatment; (4) its stigma; (5) the professionals and women misconceptions related to perinatal depression; (6) the availability of valid and short self-report screening instruments for perinatal depression and (7) their acceptability; (8) the increase in recognition, diagnosis, and treatment rates in comparison with routine practice; (9) the opportunity, given the large number of contacts that women have with health professionals in the perinatal period; and (10) perinatal depression screening potential cost-effectiveness
The shape of our gut: Dissecting its impact on drug absorption in a 3D bioprinted intestinal model
The small intestine is a complex organ with a characteristic architecture and a major site for drug and nutrient absorption. The three-dimensional (3D) topography organized in finger-like protrusions called villi increases surface area remarkably, granting a more efficient absorption process. The intestinal mucosa, where this process occurs, is a multilayered and multicell-type tissue barrier. In vitro intestinal models are routinely used to study different physiological and pathological processes in the gut, including compound absorption. Still, standard models are typically two-dimensional (2D) and represent only the epithelial barrier, lacking the cues offered by the 3D architecture and the stromal components present in vivo, often leading to inaccurate results. In this work, we studied the impact of the 3D architecture of the gut on drug transport using a bioprinted 3D model of the intestinal mucosa containing both the epithelial and the stromal compartments. Human intestinal fibroblasts were embedded in a previously optimized hydrogel bioink, and enterocytes and goblet cells were seeded on top to mimic the intestinal mucosa. The embedded fibroblasts thrived inside the hydrogel, remodeling the surrounding extracellular matrix. The epithelial cells fully covered the hydrogel scaffolds and formed a uniform cell layer with barrier properties close to in vivo. In particular, the villus-like model revealed overall increased permeability compared to a flat counterpart composed by the same hydrogel and cells. In addition, the efflux activity of the P-glycoprotein (P-gp) transporter was significantly reduced in the villus-like scaffold compared to a flat model, and the genetic expression of other drugs transporters was, in general, more relevant in the villus-like model. Globally, this study corroborates that the presence of the 3D architecture promotes a more physiological differentiation of the epithelial barrier, providing more accurate data on drug absorbance measurements.Copyright © 2023. Published by Elsevier B.V
Local iron homeostasis in the breast ductal carcinoma microenvironment
Abstract
BACKGROUND:
While the deregulation of iron homeostasis in breast epithelial cells is acknowledged, iron-related alterations in stromal inflammatory cells from the tumor microenvironment have not been explored.
METHODS:
Immunohistochemistry for hepcidin, ferroportin 1 (FPN1), transferrin receptor 1 (TFR1) and ferritin (FT) was performed in primary breast tissues and axillary lymph nodes in order to dissect the iron-profiles of epithelial cells, lymphocytes and macrophages. Furthermore, breast carcinoma core biopsies frozen in optimum cutting temperature (OCT) compound were subjected to imaging flow cytometry to confirm FPN1 expression in the cell types previously evaluated and determine its cellular localization.
RESULTS:
We confirm previous results by showing that breast cancer epithelial cells present an 'iron-utilization phenotype' with an increased expression of hepcidin and TFR1, and decreased expression of FT. On the other hand, lymphocytes and macrophages infiltrating primary tumors and from metastized lymph nodes display an 'iron-donor' phenotype, with increased expression of FPN1 and FT, concomitant with an activation profile reflected by a higher expression of TFR1 and hepcidin. A higher percentage of breast carcinomas, compared to control mastectomy samples, present iron accumulation in stromal inflammatory cells, suggesting that these cells may constitute an effective tissue iron reservoir. Additionally, not only the deregulated expression of iron-related proteins in epithelial cells, but also on lymphocytes and macrophages, are associated with clinicopathological markers of breast cancer poor prognosis, such as negative hormone receptor status and tumor size.
CONCLUSIONS:
The present results reinforce the importance of analyzing the tumor microenvironment in breast cancer, extending the contribution of immune cells to local iron homeostasis in the tumor microenvironment context.info:eu-repo/semantics/publishedVersio
Impact of Safety-Related Dose Reductions or Discontinuations on Sustained Virologic Response in HCV-Infected Patients: Results from the GUARD-C Cohort.
BACKGROUND: Despite the introduction of direct-acting antiviral agents for chronic hepatitis C virus (HCV) infection, peginterferon alfa/ribavirin remains relevant in many resource-constrained settings. The non-randomized GUARD-C cohort investigated baseline predictors of safety-related dose reductions or discontinuations (sr-RD) and their impact on sustained virologic response (SVR) in patients receiving peginterferon alfa/ribavirin in routine practice. METHODS: A total of 3181 HCV-mono-infected treatment-naive patients were assigned to 24 or 48 weeks of peginterferon alfa/ribavirin by their physician. Patients were categorized by time-to-first sr-RD (Week 4/12). Detailed analyses of the impact of sr-RD on SVR24 (HCV RNA <50 IU/mL) were conducted in 951 Caucasian, noncirrhotic genotype (G)1 patients assigned to peginterferon alfa-2a/ribavirin for 48 weeks. The probability of SVR24 was identified by a baseline scoring system (range: 0-9 points) on which scores of 5 to 9 and <5 represent high and low probability of SVR24, respectively. RESULTS: SVR24 rates were 46.1% (754/1634), 77.1% (279/362), 68.0% (514/756), and 51.3% (203/396), respectively, in G1, 2, 3, and 4 patients. Overall, 16.9% and 21.8% patients experienced ≥1 sr-RD for peginterferon alfa and ribavirin, respectively. Among Caucasian noncirrhotic G1 patients: female sex, lower body mass index, pre-existing cardiovascular/pulmonary disease, and low hematological indices were prognostic factors of sr-RD; SVR24 was lower in patients with ≥1 vs. no sr-RD by Week 4 (37.9% vs. 54.4%; P = 0.0046) and Week 12 (41.7% vs. 55.3%; P = 0.0016); sr-RD by Week 4/12 significantly reduced SVR24 in patients with scores <5 but not ≥5. CONCLUSIONS: In conclusion, sr-RD to peginterferon alfa-2a/ribavirin significantly impacts on SVR24 rates in treatment-naive G1 noncirrhotic Caucasian patients. Baseline characteristics can help select patients with a high probability of SVR24 and a low probability of sr-RD with peginterferon alfa-2a/ribavirin.This study was sponsored by F. Hoffmann-La Roche Ltd, Basel, Switzerland. Support for third-party writing
assistance for this manuscript, furnished by Blair Jarvis MSc, ELS, of Health Interactions, was provided by F. Hoffmann-La Roche Ltd, Basel, Switzerland
QUALITY OF REFRIGERATED RAW MILK FROM BUFFALO COWS (Bubalus bubalis bubalis) IN DIFFERENT FARMS AND SEASONS IN BRAZIL
The present research aimed to examine the chemical and microbiological characteristics of refrigerated raw milk collected from buffalo-only dairy herds from different farms and seasons. Samples were collected from twelve farms producing buffalo milk, located in the Mideast region of São Paulo state, in Brazil, once a month throughout the dairy calendar year from 2011 to 2014. The analysis of fat, protein, lactose, dry extract, and total solids contents were carried out using Infrared Absorption. Residues for antimicrobial analysis were carried out using Delvo Test Kit technique, and both somatic cell count and standard plate count analysis were carried out using Flow Cytometry. The analysis of the chemical components as well as for the microbiological analysis of SPC proved to be statistically significant throughout the period. No antibiotic residues were found in the totality of the sample, hence indicating that the farmers complied with the current sanitary legislation in that country, as well as SCC; however, higher values were found for the SPC. Significant results for all parameters analyzed were found among the farms, indicating that price incentives paid for the quality of raw milk could be an alternative to dairy processing companies, favoring yield and quality of the final product.
Keywords: Brazil; chemical parameters; dairy; microbiological parameters; monitoring
Copy number variation in Parkinson's disease
A central theme of human genetic studies is to understand genomic variation and how this underlies the inherited basis of disease. Genomic variation can provide increased biological understanding of disease processes, which is necessary to develop future treatments. Recent technological advances have highlighted the role of copy number variants in normal and pathological phenotypic expression. These applications have been used in studies of Parkinson's disease, a common, late-onset, progressive neurodegenerative disorder. At present the main therapeutic approach is administration of symptom-alleviating drugs, which neither reverses the disease process nor halts its progression. However, the generation of in vivo model systems and development of novel disease intervention strategies for Parkinson's disease have come from research on monogenic forms of the disorder, including those caused by copy number variants. Here, we review the role of copy number variants and the mechanistic insights they have provided on the pathogenesis of Parkinson's disease
Condições limitadoras para a integralidade do cuidado à criança na atenção básica de saúde
Protective effect of simvastatin in the cyclophosphamide-induced hemohrragic cystitis in rats
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