Analyzing Conformational Changes in the Binding of HIV-1 Matrix Protein, N and C Terminals, to Calmodulin

Worldwide, more than 38 million people are living with human immunodeficiency virus (HIV), about 84 million people have become infected with HIV since the start of the epidemic, and 40.1 million of those diagnoses led to death. HIV Type-1 is the most common type of HIV, attacking the body’s immune system by destroying CD4 cells. The virus attaches itself to the CD4 cell, taking control of its DNA and replicating itself to release more HIV into the bloodstream. The Gag proteins of HIV-1 are crucial players in the virus’ assembly, release, and maturation; it utilizes its essential matrix protein (MA) to target the plasma membrane, allowing the virus to continue its replication cycle. Calmodulin (CaM) is a calcium-sensing protein that acts as a regulator molecule in many cellular functions. When calmodulin is bound to the HIV-1 matrix protein, two alpha helices form instead of the typical one, which has yet to be fully understood. Current research has suggested that in the binding between HIV-1 MA and CaM, the myristyl group within the MA becomes exposed and anchors down to the plasma membrane. CaM has been shown to be upregulated in the presence of HIV infections, and this rise is correlated to the increased accessibility of the MA’s binding sites. The matrix protein also contains tryptophan –– a fluorescent compound that varies in intensity based on conformation type –– which can be observed through fluorescence spectroscopy and anisotropy techniques. These binding effects are hypothesized to facilitate increased viral production of HIV-1, implying that the hindering of the matrix protein binding site could lead to reduced viral replication. This project aims to examine and analyze these interactions between HIV-MA and CaM in the presence and absence of calcium using fluorescence spectroscopy

Analyzing Interactions of Calmodulin with HIV-1 Matrix Protein

Human immunodeficiency virus (HIV) attacks the immune system and if left untreated, could cause acquired immunodeficiency syndrome (AIDS). The HIV matrix protein (HIV-MA) is involved in replication and regulation of the HIV virus. Calmodulin (CaM), a calcium-binding protein found in all eukaryotes, has a potential role in the viral replication of HIV-MA which plays a key role in the replication of HIV. In order to investigate the interactions between calmodulin and the HIV-MA, a series of titrations with CaM are performed using circular dichroism. Circular dichroism (CD) uses circularly polarized light to observe the secondary structure of a molecule. The circularly polarized light is broken up into left and right components. When the molecule contains a chiral center, the left and right components are absorbed to different extents, and the differential absorption is measured with CD. Through a series of titrations, the chemical environment is changed in small increments so the molecule will experience conformational changes. As the conformation changes, CD is used to measure the ellipticity which provides a better understanding of the secondary structure that is a result of these chemical interactions. Since CaM plays a potential role in the viral replication of HIV-MA, CD is used to investigate the protein-protein interactions and conformational changes

An infrared integrated optic astronomical beam combiner for stellar interferometry at 3-4 microns

Integrated-optic, astronomical, two-beam and three-beam, interferometric combiners have been designed and fabricated for operation in the L band (3 - 4 microns) for the first time. The devices have been realized in titanium-indiffused, x-cut lithium niobate substrates, and on-chip electro-optic fringe scanning has been demonstrated. White light fringes were produced in the laboratory using the two-beam combiner integrated with an on-chip Y-splitter.Comment: This paper was published in Optics Express and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://www.opticsinfobase.org/oe. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under la

Analysis of comorbid factors that increase the COPD assessment test scores

Background: The chronic obstructive pulmonary disease (COPD) Assessment Test (CAT) is a concise health status measure for COPD. COPD patients have a variety of comorbidities, but little is known about their impact on quality of life. This study was designed to investigate comorbid factors that may contribute to high CAT scores. Methods: An observational study at Keio University and affiliated hospitals enrolled 336 COPD patients and 67 non-COPD subjects. Health status was assessed by the CAT, the St. Georges Respiratory Questionnaire (SGRQ), and all components of the Medical Outcomes Study Short-Form 36-Item (SF-36) version 2, which is a generic measure of health. Comorbidities were identified based on patients’ reports, physicians’ records, and questionnaires, including the Frequency Scale for the Symptoms of Gastro-esophageal reflux disease (GERD) and the Hospital Anxiety and Depression Scale. Dual X-ray absorptiometry measurements of bone mineral density were performed. Results: The CAT showed moderate-good correlations with the SGRQ and all components of the SF-36. The presence of GERD, depression, arrhythmia, and anxiety was significantly associated with a high CAT score in the COPD patients. Conclusions: Symptomatic COPD patients have a high prevalence of comorbidities. A high CAT score should alert the clinician to a higher likelihood of certain comorbidities such as GERD and depression, because these diseases may co-exist unrecognize

In vitroNeo-Genesis of Tendon/Ligament-Like Tissue by Combination of Mohawk and a Three-Dimensional Cyclic Mechanical Stretch Culture System

Tendons and ligaments are pivotal connective tissues that tightly connect muscle and bone. In this study, we developed a novel approach to generate tendon/ligament-like tissues with a hierarchical structure, by introducing the tendon/ligament-specific transcription factor Mohawk (MKX) into the mesenchymal stem cell (MSC) line C3H10T1/2 cells, and by applying an improved three-dimensional (3D) cyclic mechanical stretch culture system. In our developed protocol, a combination of stableMkxexpression and cyclic mechanical stretch synergistically affects the structural tendon/ligament-like tissue generation and tendon related gene expression. In a histological analysis of these tendon/ligament-like tissues, an organized extracellular matrix (ECM), containing collagen type III and elastin, was observed. Moreover, we confirmed thatMkxexpression and cyclic mechanical stretch, induced the alignment of structural collagen fibril bundles that were deposited in a fibripositor-like manner during the generation of our tendon/ligament-like tissues. Our findings provide new insights for the tendon/ligament biomaterial fields

Comprehensive biomarker analyses identifies HER2, EGFR, MET RNA expression and thymidylate synthase 5'UTR SNP as predictors of benefit from S-1 adjuvant chemotherapy in Japanese patients with stage II/III gastric cancer

Purpose: A comprehensive molecular analysis was conducted to identify prognostic and predictive markers for adjuvant S-1 chemotherapy in stage II/III Japanese gastric cancer (GC) patients and to evaluate their potential suitability for alternative cytotoxic or targeted drugs. Experimental Design: We investigated genetic polymorphisms of enzymes potentially involved in 5-fluoruracil (5-FU) metabolism as well as platinum resistance, previously identified genomic subtypes potentially predicting 5-FU benefit, and mRNA expression levels of receptor tyrosine kinases and KRAS as potential treatment targets in a single institution cohort of 252 stage II/III GC patients treated with or without S-1 after D2 gastrectomy. Results: 88% and 62% GC had a potentially 5-FU sensitive phenotype by SNP analyses of TS 3'UTR, and TS 5'UTR, respectively. 24%, 46%, 40%, 5%, and 44% GC had a potentially platinum sensitive phenotype by SNP analyses of GSTP1, ERCC1 rs11615, ERCC1 rs3212986, ERCC2, and XRCC1, respectively. High HER2, EGFR, FGFR2, or MET mRNA expression was observed in 49%, 66%, 72%, and 54% GC, respectively. High HER2 expression was the only significant prognosticator (HR=3.912, 95%CI: 1.706-8.973, p=0.0005). High HER2 (p=0.031), low EGFR (p=0.124), high MET (p=0.165) RNA expression, and TS 5'UTR subtype 2R/2R, 2R/3C, or 3C (p=0.058) were significant independent predictors for S-1 resistance. Conclusions: The present study suggests that platinum-based or RTK targeted agents could be alternative treatment options for a substantial subgroup of Japanese GC patients currently treated with S-1. HER2, EGFR, MET, and TS 5'UTR SNP appear to be promising predictive markers for S-1 resistance warranting validation in an independent GC series

The Order Calculation in the Engineering Company

Import 23/07/2015Diplomová práce je zpracovávána ve společnosti Hagemann a.s. Celá práce se zabývá kalkulací veřejné zakázky Ministerstva vnitra ČR na dodání speciálně upravených policejních vozidel pro monitoring reálných hrozeb. Diplomová práce je rozdělena na dvě základní části, a to teoretickou část a praktickou část. První z částí je popsána problematika veřejných zakázek a hospodářská činnost v podniku. V druhé části je proveden rozbor předmětu veřejné zakázky. Dále byl zpracován návrh postupu plnění zakázky v prostorách společnosti, na které navazuje cenová kalkulace. V závěru práce jsou výsledky práce vyhodnoceny.Master thesis is processed in the company Hagemann a.s. The thesis deals with the calculation of public procurement from Ministry of the Interior to supply police vehicles specially adapted for monitoring real threats. The thesis is divided into two parts, the theoretical and practical part. The first part describes the issue of public procurement and economic activities in the company. The second part is analyzing subject of the contract. Further was processed a proposal for the execution of the contract in the company's premises, which is followed by a calculation and types of costs. In conclusion, the results of the work are evaluated.345 - Katedra mechanické technologievýborn