500 research outputs found
Signaling complexes formed by luteinizing hormone receptor trans-activation
2019 Fall.Includes bibliographical references.Signal transduction by luteinizing hormone (LH) receptors depends on hormone activation of these receptors, a process important for mammalian reproduction. The LH receptor, a member of the G protein-coupled receptor (GPCR) family, undergoes hormone-induced LH receptor dimerization and/or oligomerization and translocation into small membrane compartments where receptors are confined and exhibit slow lateral diffusion. However, the organization of the signaling complex confined within these structures is not clear. In this project, we used single particle tracking methods to evaluate the lateral motions of wild type receptor FLAG-LHR-YFP and mutant receptors defective in hormone binding (LHR-hCG,+cAMP) or defective in signal transduction (LHR+hCG,-cAMP) after exposure to human chorionic gonadotropin (hCG). These studies showed that, when wild type LH receptors and mutant receptors are coexpressed and treated with 100 nM hCG, there are decreases in receptor lateral diffusion, the number of receptor-occupied membrane microdomains and the size of receptor-containing membrane microdomains. These results suggest that wild type LH receptors are capable of both cis-activation of nearby wild type LH receptors and transactivation of LHR-hCG,+cAMP , a receptor that is not able to bind hCG. We then investigated interactions between wild type LH receptors and mutant receptors using homo-transfer fluorescence resonance energy transfer (FRET) methods. We showed that LH receptors associate with one another and that the extent of self-association increases in response to increasing hCG concentrations. Using homo-transfer FRET methods, we showed that mutant LH receptors are trans-activated by wild type receptors and undergo aggregation in response to 100 nM hCG despite being unable to bind hCG directly. Finally, we evaluated cAMP levels in cis-activated and trans-activated LH receptors using ICUE3, an EPAC-based reporter molecule for cAMP. We determined that increases in intracellular cAMP occur in cells expressing wild type receptors and exposed to increasing concentrations of hCG. Similarly, cells co-expressing mutant receptors exhibit increased cAMP when there is a 1:10 transfection ratio of LHR+hCG,-cAMP to LHR-hCG,+cAMP indicating that trans-activation is occurring. Disruption of membrane microdomains by pre-treatment of cells with 10 nM methyl-β-cyclodextrin for an hour has a negative effect on cAMP levels which indicates the importance of cholesterol-containing microdomains in signal transduction by LH receptors. Together these results demonstrate that trans-activated LH receptors can undergo receptor aggregation in response to hormone binding and can signal effectively despite the absence of a signal-transduction sequence in the mutant receptor
Giant cystic pheochromocytoma with low risk of malignancy: A case report and literature teview
Giant pheochromocytomas are rare silent entities that do not present with the classical symptoms commonly seen in catecholamine-secreting tumors. In many cases they are accidentally discovered. The algorithm to diagnose a pheochromocytoma consists of biochemical evaluation and imaging of a retroperitoneal mass. The female patient in this case report presented with a palpable abdominal mass and was cured with surgical resection. She suffered no recurrence or complications on follow-up. The left retroperitoneal mass measured 27 × 18 × 12 cm and weighed 3,315 grams. Biochemical, radiological, and pathological examinations confirmed the diagnosis of a pheochromocytoma. In this paper, we report on our experience treating this patient and provide a summary of all giant pheochromocytomas greater than 10 cm reported to date in English language medical journals. Our patient’s giant cystic pheochromocytoma was the fourth heaviest and fifth largest maximal diameter identified using our literature search criteria. Additionally, this tumor had the largest maximal diameter of all histologically confirmed benign/low metastatic risk pheochromocytomas. Giant cystic pheochromocytomas are rare entities requiring clinical suspicion coupled with strategic diagnostic evaluation to confirm the diagnosis
Program Studi Pendidikan Guru Sekolah Dasar, Universitas Sarjanawiyata Tamansiswa
Taman Muda IbuPawiyatanYogyakarta Vision is to be a quality school, arts-based cultural and educational noble character. Therefore, any learning activity seeks to implement the values of character and concepts ketamansiswaan, including on science learning (IPA). Translating that vision relevant to the purposes of science education that not only emphasizes the development of students\u27 knowledge of science, but also help the development of students into well-rounded individual with good character. This study aims to explore the implementation of character value through the development of science process skills for students with special needs, values character of the development of science process skills and the factors that influence its implementation. This study is descriptive qualitative research. Data collection techniques include observation, interviews, and documentation. Mechanical analysis of data through data reduction, data presentation, and conclusion. Testing the credibility of both the source and use triangulation techniques, the extension of observation, and check data providers (member check). Implementation of character value through the development of science process skills for students with special needs high class Taman Muda IP Yogyakarta had walked though not maximized, both in terms of planning, implementation, and assessment. The values of character can be extracted including gender, honest, independent, responsibility, willpower, and appreciate nature. Its success is influenced by the family environment, school, and community
Responding to Climate Change: A Study on Eco-Labeling Practices in Consumer Goods of Bangladesh
Eco-labeling is a marketing strategy that comes from inclined environmental awareness in the globalclimate change. The study followed a theoretical framework developed by Oyewole (2001) conceptualrelation among industrial ecology; green marketing and environmental justice make it clear how eco-labelthrough green marketing can be a tool to ensure equity in different socio-economic and environmentalperspective. The study was conducted in five super markets. The key information was collected throughobservations and depth interview from consumers and service providers. The study identified that the neweco-products formed new green market. It is observed that the green market appears to be real andgrowing. The study revealed that health and environmental concerns are main reasons why people becomeaware of eco-labeled products. The survey data evidenced that 17 percent of consumer read labels to see ifproducts were environmentally safe, 11 percent sort out products and packaging made form recycledmaterials and 7 percent said they had boycotted a company that was careless about the environment. Thestudy pointed out that there is a gap between policy and practices in eco labeling. The study recommendssome suggestions to make the success of eco-labeling in green marketing perspective such as creation ofawareness among the consumers, voluntary initiatives in environmentalism and consumerism,environmental appeals in advertising, practice of environmental protection law, integration betweenenvironmental justice and eco-system services in eco-labeling program etc.Keywords: Eco-Labeling, Environmental Justices, Ecosystem Resources, Green marketing, GreenConsumerism
Trends in Awareness and Use of Electronic Cigarettes Among US Adults, 2010–2013
Introduction: Electronic cigarette (e-cigarette) marketing has increased considerably since the product entered the US market in 2007, thereby warranting additional surveillance to monitor recent trends in population-level awareness and utilization. We assessed the prevalence, characteristics, and trends in e-cigarette awareness and use among nationally representative samples of US adults during 2010–2013. Methods: Data came from the 2010–2013 HealthStyles survey, an annual consumer-based web survey of US adults aged ≥18 years. Sample sizes ranged from 2,505 (2010) to 4,170 (2012). Descriptive statistics were used to assess e-cigarette awareness, ever use, and current use (use within the past 30 days) overall and by sex, age, race/ethnicity, education, income, US region, and cigarette smoking status. Trends were assessed using logistic regression. Results: During 2010–2013, increases (p \u3c .05) were observed for e-cigarette awareness (40.9%– 79.7%), ever use (3.3%–8.5%), and current use (1.0%–2.6%). Awareness increased among all sociodemographic subpopulations during 2010–2013 (p \u3c .05); an increase in ever use of e-cigarettes occurred among all sociodemographic groups except those aged 18–24 years, Hispanics, and those living in the Midwest (p \u3c .05). During 2010–2013, ever use increased among current (9.8%–36.5%) and former (2.5%–9.6%) cigarette smokers (p \u3c .05), but it remained unchanged among never smokers (1.3%–1.2%). Conclusions: Awareness and use of e-cigarettes increased considerably among US adults during 2010–2013. In 2013, more than one-third of current cigarette smokers reported having ever used e-cigarettes. Given the uncertain public health impact of e-cigarettes, continued surveillance of emerging use patterns is critical for public health planning
Development of Stability Indicating Media for In-Vitro Dissolution Testing of Didanosine in Pharmaceutical Dosage Forms
The present investigation is aimed at developing the stability indicating dissolution media for the determination of didanosine (DDI, a HIV-1 Reverse Transcriptase inhibitor) in pharmaceutical dosage forms for the first time. The stability of didanosine was tested in various dissolution media, ie., 0.1M HCl, pH 1.2 KCl-HCl buffer and pH 5.8, 6.2, 6.6, 7.0, 7.4 and 7.8 phosphate buffers separately. The stability was tested at room temperature and 37oC for 48 hrs. The samples were scanned for stability and the optimized samples were selected for further study. Stability studies of DDI in various media at RT and 37oC indicated that the drug is stable in pH 1.2 KCl-HCl buffer, pH 6.2 and pH 7.0 phosphate buffers in the UV region for a period of 48 hr. The λmax were found to be 248.4, 249.3 and 254.4 nm for pH 1.2 KCl-HCl buffer, pH 6.2 and pH 7.0 phosphate buffers respectively with observed low coefficient of variation o
The pseudophosphatase MK-STYX inhibits stress granule assembly independently of Ser149 phosphorylation of G3BP-1
The pseudophosphatase MK-STYX (mitogen-activated protein kinase phosphoserine/threonine/tyrosine-binding protein) has been implicated in the stress response pathway. The expression of MK-STYX inhibits the assembly of stress granules, which are cytoplasmic storage sites for mRNA that form as a protective mechanism against stressors such as heat shock, UV irradiation and hypoxia. Furthermore, MK-STYX interacts with a key component of stress granules: G3BP-1 (Ras-GTPase activating protein SH3 domain binding protein-1). Because G3BP-1 dephosphorylation at Ser149 induces stress granule assembly, we initially hypothesized that the inhibition of stress granules by MK-STYX was G3BP-1 phosphorylation-dependent. However, in the present study, using MK-STYX constructs and G3BP-1 phosphomimetic or nonphosphorylatable mutants, we show that MK-STYX inhibits stress granule formation independently of G3BP-1 phosphorylation at Ser149. The introduction of point mutations at the active site of MK-STYX that convert serine and phenylalanine to histidine and cysteine, respectively, is sufficient to generate an active enzyme. In separate experiments, we show that this active mutant, MK-STYXactive, has opposite effects to wild-type MK-STYK. Not only does MK-STYXactive induce stress granules, but also it has the capacity to dephosphorylate G3BP-1. Taken together, these results provide evidence that the pseudophosphatase MK-STYX plays a key role in the cellular response to stress
The effects of common structural variants on 3D chromatin structure
BACKGROUND: Three-dimensional spatial organization of chromosomes is defined by highly self-interacting regions 0.1-1 Mb in size termed Topological Associating Domains (TADs). Genetic factors that explain dynamic variation in TAD structure are not understood. We hypothesize that common structural variation (SV) in the human population can disrupt regulatory sequences and thereby influence TAD formation. To determine the effects of SVs on 3D chromatin organization, we performed chromosome conformation capture sequencing (Hi-C) of lymphoblastoid cell lines from 19 subjects for which SVs had been previously characterized in the 1000 genomes project. We tested the effects of common deletion polymorphisms on TAD structure by linear regression analysis of nearby quantitative chromatin interactions (contacts) within 240 kb of the deletion, and we specifically tested the hypothesis that deletions at TAD boundaries (TBs) could result in large-scale alterations in chromatin conformation. RESULTS: Large (> 10 kb) deletions had significant effects on long-range chromatin interactions. Deletions were associated with increased contacts that span the deleted region and this effect was driven by large deletions that were not located within a TAD boundary (nonTB). Some deletions at TBs, including a 80 kb deletion of the genes CFHR1 and CFHR3, had detectable effects on chromatin contacts. However for TB deletions overall, we did not detect a pattern of effects that was consistent in magnitude or direction. Large inversions in the population had a distinguishable signature characterized by a rearrangement of contacts that span its breakpoints. CONCLUSIONS: Our study demonstrates that common SVs in the population impact long-range chromatin structure, and deletions and inversions have distinct signatures. However, the effects that we observe are subtle and variable between loci. Genome-wide analysis of chromatin conformation in large cohorts will be needed to quantify the influence of common SVs on chromatin structure
Metal-assisted red light-induced efficient DNA cleavage by dipyridoquinoxaline-copper(II) complex
Complete cleavage of double stranded pUC19 DNA by the complex [Cu(dpq)2(H2O)](ClO4)2 (dpq, dipyridoquinoxaline) has been observed on irradiation at 694 nm from a pulsed ruby laser, assisted by the metal d-band transition as well as the quinoxaline triplet states in the absence of any external additives
Hermite Coherent States for Quadratic Refractive Index Optical Media
Producción CientÃficaLadder and shift operators are determined for the set of Hermite–Gaussian modes associated with an optical medium with quadratic refractive index profile. These operators allow to establish irreducible representations of the su(1, 1) and su(2) algebras. Glauber coherent states, as well as su(1, 1) and su(2) generalized coherent states, were constructed as solutions of differential equations admitting separation of variables. The dynamics of these coherent states along the optical axis is also evaluated.MINECO grant MTM2014-57129-C2-1-P and Junta de Castilla y Leon grant VA057U16
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