209 research outputs found
The Possible Impact of Obesity on Androgen, Progesterone and Estrogen Receptors (ERα and ERβ) Gene Expression in Breast Cancer Patients
Background Obesity has been associated with increased mortality from hormone dependant cancers such as breast cancer which is the most prevalent cancer in women. The link between obesity and breast cancer can be attributed to excess estrogen produced through aromatization in adipose tissue. The role of steroid hormone receptors in breast cancer development is well studied but how obesity can affect the expression pattern of steroid hormones in patients with different grades of breast cancer was the aim of this study. Methods In this case-control study, 70 women with breast cancer participated with different grades of obesity (36 none obese, BMI < 25 kg/m 2 and 34 obese, BMI ≥ 25 kg/m 2 ). The mean age of participants was 44.53 ± 1.79 yr (21–70 yr). The serum level of estrogen, progesterone and androgen determined by ELISA. Following quantitative expression of steroid hormone receptors mRNA in tumor tissues evaluated by Real-time PCR. Patients with previous history of radiotherapy or chemotherapy were excluded. SPSS 16 was used for data analysis and P < 0.05 considered statistically significant. Results The difference in ERα, ERβ and PR mRNA level between normal and obese patients was significant ( P < 0.001). In addition, the expression of AR mRNA was found to be higher than other steroid receptors. There was no significant relation between ERβ gene expression in two groups ( P = 0.68). We observed a significant relationship between ERα and AR mRNA with tumor stage and tumor grade, respectively ( P = 0.023, P = 0.015). Conclusion According to the obtained results, it is speculated that obesity could paly a significant role in estrogen receptors gene expression and also could affect progression and proliferation of breast cancer cells
Geometrical inspection of flexible parts using intrinsic geometry
The tolerancing of mechanical parts is one of the major problems in mode mindustry . It's economic consequences are important to the manufacturing sector which sustains major transformations imposed by market globalization and technology evolution (CAD, CMM, 3D Scanners, etc.). Today, we know that product performance optimization requires a consideration of the inherent variations in manufacturing processes, hence quality control throughout the development process and manufacturing. Currently, the geometric inspection oiflexible (or nonrigid) mechanical parts, such as thin-walled skins of airplane or car bodies is still limited to the use of relatively expensive special inspection fixtures, which simulate the use state, applying the same constraints that reflect assembly information. Subsequently, contact measuring or scanning is performed. Simulating this use state means that, deformation effects due to flexibility are eliminated. In this way, defects in the manufacturing process are detectable.
The goal of this thesis is to facilitate the dimensional and geometrical inspection of flexible components from a point cloud without using a jig or secondary conformation operation. More specifically, we aim to develop a methodology to localize and quantify the profile defects in the case of thin shells which are typical to the aerospace and automotive industries.
To this end, we implemented an idea that we call Numerical Inspection Fixtures. We use geodesic distances to detect the intrinsic similarities between a part in a free state which includes the effects of gravity, intemal constraints and manufacturing defects, and the same part as nominally defined by a CAD model. This thesis develops the theoretical foundation of the proposed methods and related algorithms. We used an approach already used in medical image processing to identify minimum geodesic distance and statistics (Multidimensional Scaling) to analyze the similarities and dissimilarities between two objects, as well as the finite element method to reach a general approach for the inspection of nonrigid parts. Two methods are proposed with numerical validations
Fixtureless geometric inspection of nonrigid parts using "generalized numerical inspection fixture"
Free-form nonrigid parts form the substance of today’s automotive and aerospace industries. These parts have different shapes in free state due to their dimensional and geometric variations, gravity and residual strains. For the geometric inspection of such compliant parts, special inspection fixtures, in combination with coordinate measuring systems (CMM) and/or optical data acquisition devices (scanners) are used. This inevitably causes additional costs and delays that result in a lack of competitiveness in the industry.
The goal of this thesis is to facilitate the dimensional and geometrical inspection of flexible components from a point cloud without using a jig or secondary conformation operation. More specifically, we aim to develop a methodology to localize and quantify the profile defects in the case of thin shells which are typical to the aerospace and automotive industries.
The presented methodology is based on the fact that the interpoint geodesic distance between any two points of a shape remains unchangeable during an isometric deformation. This study elaborates on the theory and general methods for the metrology of nonrigid parts. We have developed a Generalized Numerical Inspection Fixture (GNIF), a robust methodology which merges existing technologies in metric and computational geometry, nonlinear dimensionality reduction techniques, and finite element methods to introduce a general approach to the fixtureless geometrical inspection of nonrigid parts
High-salt diet causes osmotic gradients and hyperosmolality in skin without affecting interstitial fluid and lymph
The common notion is that the body Na+ is maintained within narrow limits for fluid and blood pressure homeostasis. Several studies have, however, shown that considerable amounts of Na+ can be retained or removed from the body without commensurate water loss and that the skin can serve as a major salt reservoir. Our own data from rats have suggested that the skin is hypertonic compared with plasma on salt storage and that this also applies to skin interstitial fluid. Even small electrolyte gradients between plasma and interstitial fluid would represent strong edema-generating forces. Because the water accumulation has been shown to be modest, we decided to reexamine with alternative methods in rats whether interstitial fluid is hypertonic during salt accumulation induced by high-salt diet (8% NaCl and 1% saline to drink) or deoxycorticosterone pellet implantation. These treatments resulted both in increased systemic blood pressure, skin salt, and water accumulation and in skin hyperosmolality. Interstitial fluid isolated from implanted wicks and lymph draining the skin was, however, isosmotic, and Na+ concentration in fluid isolated by centrifugation and in lymph was not different from plasma. Interestingly, by eluting layers of the skin, we could show that there was an osmolality and urea gradient from epidermis to dermis. Collectively, our data suggest that fluid leaving the skin as lymph is isosmotic to plasma but also that the skin can differentially control its own electrolyte microenvironment by creating local gradients that may be functionally important.acceptedVersio
Global Trend in Exosome Isolation and Application: An Update Concept in Management of Diseases
Extracellular vesicles (EVs) secreted by various cells offer great potential for use in the diagnosis and treatment of disease. EVs are heterogeneous membranous vesicles. Exosomes are a subtype of EVs, 40-150 nm spherical vesicles with a lipid layer derived from endosomes. Exosomes, which are involved in signal transduction and maintain homeostasis, are released from almost all cells, tissues, and body fluids. Although several methods exist to isolate and characterize EVs and exosomes, each technique has significant drawbacks and limitations that prevent progress in the field. New approaches in the biology of EVs show great potential for isolating and characterizing EVs, which will help us better understand their biological function. The strengths and limitations of conventional strategies and novel methods (microfluidic) for EV isolation are outlined in this review. We also present various exosome isolation techniques and kits that are commercially available and assess the global market demand for exosome assays
Melissa officinalis L. ethanolic extract inhibits the growth of a lung cancer cell line by interfering with the cell cycle and inducing apoptosis
Melissa officinalis is a plant from the family Lamiaceae, native in Europe particularly in the Mediterranean
region. Given our interest in identifying extracts and compounds capable of inhibiting tumor cell growth,
and given the antioxidant content and the high consumption of Melissa officinalis in Portugal, this study
aimed to test the tumor cell growth inhibitory activity of five different extracts of this plant (aqueous,
methanolic, ethanolic, hydromethanolic and hydroethanolic) in three human tumor cell lines: MCF-7,
AGS and NCI-H460. All extracts decreased cell growth in all cell lines in a concentration-dependent
manner. The ethanolic extract was the most potent one, presenting a GI50 concentration of approximately
100.9 μg mL−1 in the NCI-H460 lung cancer cells. This extract was characterized by LC-DAD-ESI/MS
regarding its phenolic composition, revealing rosmarinic acid as the most abundant compound. The GI75
concentration of this extract affected the cell cycle profile of these cells. In addition, both the GI50 and
the GI75 concentrations of the extract induced cellular apoptosis. Moreover, treatment of NCI-H460 cells
with this extract caused a decrease in pro-caspase 3 and an increase in p53 levels. This study emphasizes
the relevance of the study of natural products as inhibitors of tumor cell growth.This work was financed by the FEDER - Fundo Europeu de
Desenvolvimento Regional through the COMPETE 2020 –
Operational Programme for Competitiveness and
Internationalisation (POCI), Portugal 2020, and by Portuguese
funds through FCT – Fundação para a Ciência e Tecnologia/
Ministério da Ciência, Tecnologia e Inovação in the framework
of the project “Institute for Research and Innovation in Health
Sciences” (POCI-01-0145-FEDER-007274). The authors are also
grateful to FCT and FEDER under Programme PT2020 for financial
support to CIMO (UID/AGR/00690/2013) and L. Barros contract;
and to FEDER-Interreg España-Portugal programme for
financial support through the project 0377_Iberphenol_6_E.info:eu-repo/semantics/publishedVersio
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