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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
401

Análise de polimorfismos dos genes KIR e HLA em pacientes com vitiligo

Dias, Vanessa Guterres January 2014 (has links)
O vitiligo é uma doença dermatológica de causa desconhecida. O aparecimento se dá através de manchas branco-nacaradas na pele, ocorridas pela morte ou redução na funcionalidade das células epidérmicas, os melanócitos, que produzem a melanina, pigmento cutâneo. As células Natural Killer (NK) fazem parte do sistema imune inato e através de seus receptores KIR (Killer immunoglobulin-like-receptors) reconhecem moléculas de HLA (Human leukocyte antigen) classe I presentes nas células. Quando não há o reconhecimento do HLA classe I, como em células tumorais ou infectadas por vírus, a célula NK induz a morte da célula alvo. Uma das teorias para essa doença é a imunológica, a qual admite que o vitiligo seja doença autoimune pela formação de anticorpos antimelanócitos, podendo ser associado a outras doenças autoimunes. O objetivo deste estudo foi investigar polimorfismos dos genes KIR e HLA e sua associação com pacientes com vitiligo comparando com um grupo controle. Foram genotipados 112 pacientes com diagnóstico de vitiligo e 250 indivíduos saudáveis para 16 genes KIR e seus ligantes HLA por PCR-SSO e PCR-SSP respectivamente. Nossos resultados mostraram um fator de risco para a doença na interação do gene ativador KIR2DS1 com o seu ligante C2 (P=0,015; OR: 2,06). Também houve uma associação significativa do gene ativador KIR2DS1 com o ligante heterozigoto C1/C2 (P=0,025; OR: 2,26). A interação KIR2DS1/C2 está presente em 52,8% dos pacientes com vitiligo e em 35,2% do grupo controle, já a interação KIR2DS1/C1/C2 está presente em 54,7% dos pacientes com vitiligo e 34,9% do grupo controle. Nossos resultados sugerem um possível fator de risco do gene ativador KIR2DS1 com o seu ligante C2, sendo essa combinação uma possível susceptibilidade à doença. / Vitiligo is a skin disease of unknown cause. The main symptom of vitiligo is white patches on the skin. Which are caused by destruction of pigment-forming cells (melanocytes). Natural killer (NK) cells are part of the innate immune system and they recognize class I HLA molecules (human leukocyte antigen) through their KIR receptors (killer-cell immunoglobulin-like-receptors). When class I HLA molecules are not recognized, e.g.: tumour cells or virus-infected cells, NK cells induce the death of target cells. One of the possible aetiologies for this disease is the immune cause. According to this theory, vitiligo is an autoimmune disease caused by the production of anti-melanocyte antibodies and it may be associated with other autoimmune diseases. The objective of the present study was to investigate KIR and HLA gene polymorphisms and their association with vitiligo comparing with a control group. We genotyped 112 patients diagnosed with vitiligo and 250 healthy individuals for 16 KIR genes and their HLA ligands using PCR-SSO and PCR-SSP respectively. Our findings showed a risk factor for vitiligo in the interaction between the activating KIR2DS1 gene and its C2 ligand (P=0.015; OR: 2.06). There was also a significant association of the activating KIR2DS1 gene with the heterozygous C1/C2 ligand (P=0.025; OR: 2.26). The KIR2DS1/C2 interaction was found in 52.8% of vitiligo patients and in 35.2% of the control group; whereas the KIR2DS1/C1/C2 interaction was found in 54.7% of vitiligo patients and 34.9% of the control group. These findings suggest a possible risk factor related to the interaction between the activating KIR2DS1 gene and its C2 ligand, since this combination may be a disease susceptibility factor.
402

Distribuição de polimorfismos de base única (SNPs) em genes relacionados à infecção pelo HIV-1 em uma população do Nordeste Brasileiro

Silva, Ronaldo Celerino da 04 March 2015 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2015-05-14T16:07:52Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese Ronaldo Celerino_Biblioteca.pdf: 11538818 bytes, checksum: bb7cc47b8cb9d49a4b1e691267ae2ff3 (MD5) / Made available in DSpace on 2015-05-14T16:07:52Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese Ronaldo Celerino_Biblioteca.pdf: 11538818 bytes, checksum: bb7cc47b8cb9d49a4b1e691267ae2ff3 (MD5) Previous issue date: 2015-03-04 / CAPES, CNPq / A variabilidade genética humana tem desempenhado um papel importante para a compreensão de mecanismos envolvidos na susceptibilidade à infeção pelo HIV-1. O presente trabalho avaliou as distribuições de polimorfismos de base única (SNPs) em genes humanos relacionados à entrada (CCL3, CCL4, CCL5, CXCL12, CXCR6) e à replicação viral (APOBEC3G, CUL5, TRIM5, HLA-C e ZNRD1), e suas prováveis associações com a modulação da susceptibilidade à infecção pelo HIV-1 em uma população do Nordeste brasileiro (Recife-Pernambuco), a fim de estabelecer um modelo imunogenético de susceptibilidade ao HIV-1. Foi desenvolvido um estudo tipo caso-controle, utilizando pacientes infectados (HIV-1+) e controles saudáveis, os quais foram genotipados para 18 SNPs em genes reconhecidamente envolvidos na entrada e na replicação viral. Verificou-se que variantes nos genes CCL3 (rs1719134), CCL4 (rs1719153), TRIM5 (rs10838525) e CUL5 (rs11212495) foram mais frequentes em controles saudáveis; enquanto variantes em APOBEC3G e ZNRD1 (rs3869068) foram mais frequentes em pacientes HIV-1+, sugerindo, respectivamente, proteção e susceptibilidade à infecção pelo HIV-1 na população pernambucana. Neste sentido, sugere–se que SNPs em genes relacionados com a entrada e a replicação viral podem modular a susceptibilidade a infecção pelo HIV-1.
403

Identificação dos subtipos de alelos de HLA-DRB1*04 associados à Tuberculose Pulmonar

Lima, Dhêmerson Souza de 08 May 2015 (has links)
Submitted by Lúcia Brandão (lucia.elaine@live.com) on 2015-12-11T19:01:49Z No. of bitstreams: 1 Dhêmerson - Dhêmerson Souza de Lima.pdf: 2134258 bytes, checksum: 027d2a19329c1030eb634da31db37ae6 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-01-19T14:57:53Z (GMT) No. of bitstreams: 1 Dhêmerson - Dhêmerson Souza de Lima.pdf: 2134258 bytes, checksum: 027d2a19329c1030eb634da31db37ae6 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-01-19T15:02:05Z (GMT) No. of bitstreams: 1 Dhêmerson - Dhêmerson Souza de Lima.pdf: 2134258 bytes, checksum: 027d2a19329c1030eb634da31db37ae6 (MD5) / Made available in DSpace on 2016-01-19T15:02:05Z (GMT). No. of bitstreams: 1 Dhêmerson - Dhêmerson Souza de Lima.pdf: 2134258 bytes, checksum: 027d2a19329c1030eb634da31db37ae6 (MD5) Previous issue date: 2015-05-08 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Tuberculosis (TB) is a serious public health problem, considered as a priority by the government of Brazil since 2003. This disease is endemic in low and middle-income countries, mainly affecting the population living in urban peripheries when associated with poor living conditions, malnutrition and drug abuse. Brazil is one of 22 countries contributing to the global high TB burden; it is on 16th position in number of TB cases. In 2014, Amazonas state had the highest national incidence rate of TB (68.4 per 100.000 inhabitants). Poverty, social exclusion, operational difficulties for diagnosis and treatment of TB are crucial to maintaining the high rate of incidence. In addition, the host immunogenic factors are associated with TB. Human Leukocyte Antigen (HLA) genes are associated with susceptibility or resistance to TB. This study verifies the frequency of HLA-DRB1*04 allele and subtypes in 622 subjects (316 patients with pulmonary TB and 306 controls). HLA-DRB1*04 was more frequent in TB patients (187/316; 59,2%) than control group (101/306; 33,0%). In this study, nine subtypes of HLA-DRB1*04 were identified. The subtype HLA-DRB1*04:11:01 was associated with susceptibility to pulmonary TB (p = 0.0019; OR = 2.23; 95% CI = 1.34 to 3.70), while HLA-DRB1*04:07:01 was associated with protection (p < 0.0001; OR = 0.02; 95% CI = 0.001 to 0.33) and HLA-DRB1*04:92 was associated with transmission to pulmonary TB disease (p = 0.0112; OR = 8.62; 95% CI = 1.63 to 45.5). These results suggest three subtypes of HLA-DRB1*04 as potential immunogenetic markers in TB and can help in better understanding of mechanisms involved in disease, as well as the reasons for high rates of TB incidence in Amazonas state. / A tuberculose (TB) é um grave problema de saúde pública, considerada como prioridade pelo governo do Brasil desde 2003. A doença é endêmica nos países de baixa e média renda, acometendo principalmente a população que reside nas periferias urbanas (favelas e invasões), estando associada às más condições de moradia, à alimentação, ao saneamento básico e ao uso de drogas. O Brasil é um dos 22 países que contribuem com as maiores cargas de TB no mundo, ocupando a 16.a posição em número absoluto de casos. O Estado do Amazonas, em 2014, apresentou o maior coeficiente de incidência nacional de casos de TB (68,4 por 100 mil habitantes). Miséria, exclusão social, dificuldades operacionais de diagnósticos e tratamento da TB são preponderantes para manutenção da alta taxa de incidência. Além disso, os fatores imunogenéticos do hospedeiro são descritos e associados à suscetibilidade ou à resistência da doença. Dentre os genes mais fortemente associados à TB, estão os do Antígeno Leucocitário Humano (HLA). No presente estudo, foi investigada a frequência do alelo HLA-DRB1*04 em 622 indivíduos, 316 pacientes com TB pulmonar e 306 controles. O HLA-DRB1*04 foi frequente nos pacientes (187/316; 59,2%), quando comparado aos dados dos controles (101/306; 33,0%). Neste estudo, foram identificados nove subtipos de HLADRB1*04; destes, o HLA-DRB1*04:11:01 foi associado à suscetibilidade (p = 0,0019; OR =2,23; IC 95% = 1,34 – 3,70) e à transmissão de TB pulmonar, enquanto o HLA-DRB1*04:07:01 foi associado à proteção (p < 0,0001; OR = 0,02; IC 95% = 0,001 – 0,33), e o HLA-DRB1*04:92 foi associado à transmissão da doença (p = 0,0112; OR = 8,62; IC 95% = 1,63 – 45,5). Esses resultados sugerem três subtipos do HLA-DRB1*04 como potenciais marcadores imunogenéticos na TB, os quais podem ajudar na compreensão dos mecanismos envolvidos na doença, bem como esclarecer os motivos das altas taxas de incidência de TB no Estado do Amazonas.
404

Design, Implementation, and Performance Evaluation of HLA in Unity

Söderbäck, Karl January 2017 (has links)
This report investigates if an HLA-plugin for the game engine Unity can be made and whether or not it would lead to any drawbacks in regard to data exchange and performance. An implementation of a plugin and performance tests on it proceeds to show that the possibilities of running HLA as a plugin in Unity shows a lot of promise for 3D-applications designed in Unity communicating over HLA.
405

Quantitative assessment of HLA-DQ gene polymorphisms with the development of hepatitis B virus infection, clearance, liver cirrhosis, and hepatocellular carcinoma

Xu, Tao, Zhu, Anyou, Sun, Meiqun, Lv, Jingzhu, Qian, Zhongqing, Wang, Xiaojing, Wang, Ting, Wang, Hongtao 06 December 2017 (has links)
Hepatitis B is one of the most common infectious diseases, which leads to public health problems in the world, especially in Asian counties. In recent years, extensive human genetic association studies have been carried out to identify susceptible genes and genetic polymorphisms to understand the genetic contributions to the disease progression of HBV infection. HLA-DQ gene variations have been reported to be associated with HBV infection/clearance, disease progression and the development of hepatitis B-related complications, including liver cirrhosis (LC) and hepatocellular carcinoma (HCC). However, the results are either inconclusive or controversial. Therefore, to derive a more precise estimation of the association, a meta-analysis was performed. Our data revealed that the HLA-DQ alleles rs2856718-G, rs7453920-A and rs9275319-G were significantly associated with decreased risk of HBV infection and HBV natural clearance. Logistic regression analyses showed that HLA-DQ alleles rs9275572-A significantly increased HBV infection clearance, and decreased HBV natural clearance. However, rs2856718-G and rs9275572-A were not associated with development of cirrhosis. The HLA-DQ polymorphisms (rs2856718 and rs9275572) were associated with a decreased HBV-related HCC risk in all genetic models, but rs9272105-A increased the risk of HBV-related HCC. In addition, no significant association was observed between HLA-DQ rs9275319-G polymorphism and HBVrelated HCC. These stratified analyses were limited due to relatively modest size of correlational studies. In future, further investigation on a large population and different ethnicities are warranted. Our findings contribute to the personalized care and prognosis in hepatitis B.
406

Real-Time Database Support for Distributed Real-Time Simulations

Brohede, Marcus January 2001 (has links)
Simulation is a good way to gain insight into a system, for example during development, without having to run or build the actual system. This is especially true for real-time systems, which often operate in hazardous environments or control critical entities in the 'real' world, making testing of these systems in their real environment unsafe during development. When building simulations, one simulator is not likely to fit every type of simulation project. Therefore, different simulators, which focus on different aspects of simulation, are built. The High Level Architecture (HLA) from the Defense Modeling and Simulation Office (DMSO) is an architecture for distributed simulations providing a means to communicate between different simulations. However, the HLA standard has limitations if viewed from a real-time perspective. For example, there is no built-in support for fault tolerance. In this thesis some of the limitations in HLA are identified and an extended architecture that uses a distributed active real-time database as a way to overcome these limitations is presented. One of the major advantages with this new extended HLA architecture is that it is still compliant with HLA, i.e., no modifications have been made to the HLA interfaces.
407

HIV subtype C diversity: analysis of the relationship of sequence diversity to proposed epitope locations

Ernstoff, Elana Ann January 2002 (has links)
Magister Scientiae - MSc / Southern Africa is facing one of the most serious HIV epidemics. This project contributes to the HIVNET, Network for Prevention Trials cohort for vaccine development. HIVÂ’s biology and rapid mutation rate have made vaccine design difficult. We examined HIV-1 subtype C diversity and how it relates to CTL epitope location along viral gag sequences. We found a negative correlation between codon sites under positive selection and epitope regions; suggesting epitope regions are evolutionarily conserved. It is possible that epitopes exist in non-conserved regions, yet fail to be detected due to the reference strain diverging from the circulating viral population. To test if CTL clustering is an artifact of the reference strain, we calculated differences between the gag codons and the reference strain. We found a weak negative correlation, suggesting epitopes in less conserved regions maybe evading detection. Locating conserved and optimal epitopes that can be recognized by CTLs is essential for the design of vaccine reagents. / South Africa
408

Performance comparison of data distribution management strategies in large-scale distributed simulation.

Dzermajko, Caron 05 1900 (has links)
Data distribution management (DDM) is a High Level Architecture/Run-time Infrastructure (HLA/RTI) service that manages the distribution of state updates and interaction information in large-scale distributed simulations. The key to efficient DDM is to limit and control the volume of data exchanged during the simulation, to relay data to only those hosts requiring the data. This thesis focuses upon different DDM implementations and strategies. This thesis includes analysis of three DDM methods including the fixed grid-based, dynamic grid-based, and region-based methods. Also included is the use of multi-resolution modeling with various DDM strategies and analysis of the performance effects of aggregation/disaggregation with these strategies. Running numerous federation executions, I simulate four different scenarios on a cluster of workstations with a mini-RTI Kit framework and propose a set of benchmarks for a comparison of the DDM schemes. The goals of this work are to determine the most efficient model for applying each DDM scheme, discover the limitations of the scalability of the various DDM methods, evaluate the effects of aggregation/disaggregation on performance and resource usage, and present accepted benchmarks for use in future research.
409

Optimisation and Validation of PCR Method for HLA Gene Expression to Enable PCR System Transfer and Master Mix Change

Odlander, Paulina January 2020 (has links)
Health Tech company Dynamic Code AB provides a PCR test for determination of HLA DQ-genes connected to development of celiac disease. The PCR method is probe based and in real time and is at this time carried through on the, somewhat outdated, PCR instrument from Thermo Fisher/Applied Biosystems called 7300 Real-Time PCR System. The run time for this analysis on the instrument is 1 hour and 50 minutes. The Master Mix in use is TaqMan™ Gene Expression Master Mix, from the same manufacturer. Moving on to a more modern PCR instrument is a natural step for the company and is favourable in several regards, one of them being the run time that will be cut by 50 minutes, allowing for more samples to be analysed in the same amount of time. The objective is to move the HLA analysis to Thermo Fisher’s QuantStudio™ 6 and 7 Flex Systems and at the same time change the Master Mix to SolisFast® Probe qPCR Mix (Purple) from Solis BioDyne, in order to achieve better accuracy as this Master Mix is more compatible with the latter instrument, along with reducing reagent cost as it is less expensive. In order to find the optimal primer and probe concentration for each target included in the HLA analysis, their concentrations were varied and tested with the new Master Mix on the new instrument. PCR instrument transfer and Master Mix change was successful and validation experiments showed a 98,9% accuracy for the new method compared to the original method.
410

iPSC-derived platelets depleted of HLA class-I are inert to anti-HLA class-I and NK cell immunity / HLAクラスIを欠失させたiPS細胞由来血小板は、抗HLAクラスI抗体とNK細胞による免疫機構を回避する

Suzuki, Daisuke 25 May 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医科学) / 甲第22648号 / 医科博第111号 / 新制||医科||7(附属図書館) / 京都大学大学院医学研究科医科学専攻 / (主査)教授 生田 宏一, 教授 竹内 理, 教授 髙折 晃史 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

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