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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.
31

Influencia dos polimorfismos nos genes CYP1A1*2A, GSTM1, GSTT1 e GSTP1*B na susceptibilidade ao cancer de pulmão / Influence of the polymorphisms CYP1A1*2A, GSTM1, GSTT1 e GSTP1*B genes on lung cancer susceptibility

Honma, Helen Naemi, 1971- 31 August 2007 (has links)
Orientadores: Lair Zambon, Carmen Silvia Passos Lima / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-09T12:57:06Z (GMT). No. of bitstreams: 1 Honma_HelenNaemi_M.pdf: 6073042 bytes, checksum: 8de4d548610b680b2101397d10fc9e52 (MD5) Previous issue date: 2007 / Resumo: A citocromo P- 450 1A1 (CYP1A1) é uma importante enzima do metabolismo carcinogênico, em virtude da regulação polimórfica, a CYP1A1 é um marcador genético promissor para susceptibilidade de certas malignidades, particularmente o câncer de pulmão (CP). A primeira variação detectada (chamada de m1 ou *2A) foi a transição de T?C no exon 7 com 1194pb, criando um sítio de clivagem para a enzima MspI. Esta alteração foi mais prevalente em Asiáticos do que em Caucasóides. Os genes GSTM1, GSTT1 e GSTP1 vem sendo estudados extensivamente em relação ao CP, pois estão relacionados com a perda completa ou redução da atividade de certos xenobióticos metabolizados por enzimas. O genótipo variante Val/Val do gene GSTP1*B tem uma maior atividade para com o epóxido diol hidrocarbono e BPDE, portanto um menor potencial de detoxificação, resultando em um grande risco para o câncer. O objetivo deste estudo foi analisar a susceptibilidade dos genes polimórficos para o risco em CP e a correlação dos genótipos com as interações das variáveis clínicas. Para cumprir tais objetivos, o DNA genômico de 200 pacientes com CP e 264 doadores de sangue (controles), foram analisados por meio da reação em cadeia da polimerase (PCR) e digestão enzimática. Freqüências similares da deleção homozigótica dos genes polimórficos isolados GSTM1 (45,5% vs 48,1% p= 0,14), GSTT1 (13,5% vs 12,9% p=0,54), GSTM1/T1 ambos nulos (6,0% vs 4,9% p=0,83), da variante Val/Val do gene GSTP1 (12,5% vs 11,4% p=0,87) e da variante CYP1A1*2A (5,5% vs 3,4% p= 0,69) foram observadas em pacientes e controles. Não foram observadas diferenças significativas entre as freqüências de todos estes genótipos. Os resultados sugerem que os genótipos isolados e combinados não influenciaram o risco para CP, mas podemos sugerir que na população Afro-Brasileira estudada, há indícios de uma associação dos genótipos hetero/ variante do gene CYP1A1*2A e GSTs possam levar a uma maior susceptibilidade para o CP / Abstract: Cytochrome P-450 A1 (CYP1A1 ) is an important enzyme of carcinogen metabolism. Due to polymorphic regulation, CYP1A1 is a biomarker of genetic susceptibility to certain malignancies, especially lung cancer (LC). The first detected variation, named m1 or *2A, was a T-to-C transition in exon 7, with 1194bp, which produced a breakage point for the MspI enzyme. Originally, more Asians than Caucasians presented with LC. Intensive studies have shown that GSTM1, GSTT1 and GSTP1 genes are related to LC, which may lead to whole loss or certain hazard reduction. The GSTP1 Val/Val variant genotype has a strong activity, especially along with hydrocarbon diol epoxide and BPDE, leading to detoxification potency. The purpose of this study was to analyze the susceptibility of polymorphism genes to LC risk and the correlation of genotypes with clinical variations. In order to achieve these objectives, the genomic DNA of 200 patients with LC and 264 blood donors (controls) were analyzed through PCR and enzymatic digestion. Similar frequencies of homozygotic deletion of polymorphic isolated genes were observed in patients and controls, as follows: GSTM1 (45.5% vs 48.1%, p= 0.14), GSTT1 (13.5% vs 12.9%, p= 0.54), GSTM1/T1 both null (6.0% vs 4.9%, p= 0.83), GSTP1 gene Val/Val variant (12.5% vs 11.4%, p= 0.87) and the CYP1A1*2A variant (5.5% vs 3.4%, p= 0.69). The differences observed among the frequencies of all combined genotypes were not significant. The final results suggested that isolated and combined genotypes did not influence LC risk; on the other hand, there is a high susceptibility for LC in African-Brazilian people with CYP1A1*2A and GSTs hetero/variant genotype / Mestrado / Clinica Medica / Mestre em Clinica Medica
32

Identificação de polimorfismos genéticos com impacto no desenvolvimento  e progressão da leishmaniose visceral em indivíduos de áreas endêmicas do Maranhão e Piauí / Identificação de polimorfismos genéticos com impacto no desenvolvimento e progressão da leishmaniose visceral em indivíduos de áreas endêmicas do Maranhão e Piauí

Amanda Farage Frade 12 July 2010 (has links)
A leishmaniose visceral constitui grave doença infecciosa causada por um protozoário parasita intracelular obrigatório. Alguns fatores podem alterar a gravidade das manifestações clínicas, sendo um deles a predisposição genética. Este estudo investigou polimorfismos dos genes TGFB1, IL8 e IL6, que são citocinas relacionadas com o desencadeamento e a gravidade da doença, visando identificar fatores de susceptibilidade. Os polimorfismos TGFB1 -509 C/T e TGFB1 +869 T/C, IL8 -251A/T e IL6 -174G/C foram analisados por PCR-RFLP, em 198 pacientes com leishmaniose visceral (LV), 98 indivíduos com infecção assintomática (teste de hipersensibilidade tardia - DTH+) e 100 indivíduos sem evidências de infecção (DTH-). O alelo T na posição -509 do gene TGFB1 conferiu risco duas vezes maior de desenvolver LV ou ser positivo para o teste DTH (p = 0,007, OR = 1,9 [1,19-3,02]), em comparação com indivíduos DTH-. Os resultados sugerem uma associação do polimorfismo TGFB1 -509C/T com a susceptibilidade à LV, podendo contribuir para o desencadeamento da doença clínica. / Visceral leishmaniasis is a serious protozoan infectious disease caused by an obligate intracellular parasite. Some factors can affect the severity of the clinical manifestations; one of which is genetic susceptibility. This study investigated polymorphisms in the TGFB1, IL8 and IL6 genes, which are cytokines related with the onset and severity of the disease, to look for genetic susceptibility factors. Polymorphisms at TGFB1 -509C/T and +869T/C, and IL8 - 251A/T and IL6 -174G/C were analyzed by a PCR-RFLP technique, in 198 patients with Visceral Leishmaniasis (VL), 98 individuals with asymptomatic infection (positive delayed-type hypersensitivity, DTH+) and 100 individuals with no evidence of infection (DTH-). The T allele of the TGFB1 polymorphism in position -509C/T conferred a two risk fold to develop LV or to be DTH+ (p=0.007; OR=1.9 [1.19 - 3.02]) when compared with DTH- individuals. We suggest the TGFB1 -509C/T polymorphism is associated with susceptibility to LV and may contribute to development of the clinical disease.
33

Dissecting the molecular responses of Sorghum bicolor to Macrophomina phaseolina infection

Bandara, Y.M. Ananda Yapa January 1900 (has links)
Doctor of Philosophy / Department of Plant Pathology / Christopher R. Little / Charcoal rot, caused by the necrotrophic fungus, Macrophomina phaseolina (Tassi) Goid., is an important disease in sorghum (Sorghum bicolor (L.) Moench). The molecular interactions between sorghum and M. phaseolina are poorly understood. In this study, a large-scale RNA-Seq experiment and four follow-up functional experiments were conducted to understand the molecular basis of charcoal rot resistance and/or susceptibility in sorghum. In the first experiment, stalk mRNA was extracted from charcoal-rot-resistant (SC599) and susceptible (Tx7000) genotypes and subjected to RNA sequencing. Upon M. phaseolina inoculation, 8560 genes were differentially expressed between the two genotypes, out of which 2053 were components of 200 known metabolic pathways. Many of these pathways were significantly up-regulated in the susceptible genotype and are thought to contribute to enhanced pathogen nutrition and virulence, impeded host basal immunity, and reactive oxygen (ROS) and nitrogen species (RNS)-mediated host cell death. The paradoxical hormonal regulation observed in pathogen-inoculated Tx7000 was characterized by strongly upregulated salicylic acid and down-regulated jasmonic acid pathways. These findings provided useful insights into induced host susceptibility in response to this necrotrophic fungus at the whole-genome scale. The second experiment was conducted to investigate the dynamics of host oxidative stress under pathogen infection. Results showed M. phaseolina’s ability to significantly increase the ROS and RNS content of two charcoal-rot-susceptible genotypes, Tx7000 and BTx3042. Over-accumulation of nitric oxide (NO) in stalk tissues in the pathogen-inoculated susceptible genotypes was confirmed using a NO-specific fluorescent probe and confocal microscopy. Significantly increased malondialdehyde content confirmed the enhanced oxidative stress experienced by the susceptible genotypes after pathogen inoculation. These findings suggested the contribution of oxidative stress-associated induced cell death on charcoal rot susceptibility under infection. In the third functional experiment, the behavior of the sorghum antioxidant system after pathogen inoculation was investigated. M. phaseolina significantly increased the glutathione s-transferase (GST), glutathione peroxidase (GPX), glutathione reductase (GR), and peroxidase activities of the susceptible genotypes (Tx7000, BTx3042) but not in the resistant genotypes (SC599, SC35). Increased activities of these enzymes in susceptible genotypes may contribute to reduced oxidative stress thus lowering charcoal rot susceptibility. The fourth functional experiment was designed to quantify induced host-derived cell wall degrading enzymes (CWDEs) using crude enzyme mixtures from stalks. A gel diffusion assay revealed significantly increased pectinesterase activity in pathogen-inoculated Tx7000 and BTx3042 while significantly increased polygalacturonase activity was determined by absorbance. Fluorimetric determination of cell extracts revealed significantly increased cellulose degrading enzyme activity in M. phaseolina-inoculated Tx7000 and BTx3042. These findings revealed the pathogen’s ability to promote charcoal rot susceptibility in grain sorghum through induced host CWDEs. The last functional study was designed to profile the stalk tissue lipidome of Tx7000 and SC599 after M. phaseolina inoculation using automated direct infusion electrospray ionization-triple quadrupole mass spectrometry (ESI-MS/MS). M. phaseolina significantly decreased the phytosterol, phosphatidylserine, and ox-lipid contents in Tx7000 while significantly increasing stigmasterol:sitosterol ratio. Except for ox-lipid content, none of the above was significantly affected in resistant SC599. Results suggested the lethal impacts of M. phaseolina inoculation on plastid- and cell- membrane integrity and the lipid-based signaling capacity of Tx7000. Findings shed light on the host lipid classes that contribute to induced charcoal rot susceptibility in grain sorghum.
34

Genetic diversity and population structure of plasmodium falciparum from four epidemiological locations in Malawi

Selemani, George Paul January 2014 (has links)
In malaria-endemic regions, Plasmodium falciparum (P. falciparum) infection is characterized by extensive genetic/antigenic diversity. Describing this diversity provides important information about the local molecular epidemiology of infecting P. falciparum parasites. Intriguingly, one of the major obstacles to the development of an effective malaria vaccine has been the genetic polymorphisms exhibited by P. falciparum genes encoding targets of human immune system. This situation has necessitated the development of polyvalent vaccines with wide antigenic coverage that would increase the likelihood of vaccine efficacy that covers wide geographical areas of malaria endemic countries. Limited reports are available on the population genetic diversity and structure of P. falciparum in Malawi, and this is of particular concern as the country has put in place several interventions to combat the disease. The primary aim of the research project was to determine the genetic diversity and population structure of P. falciparum isolates and comparing complexity from four different epidemiological settings in Malawi using msp-2 gene polymorphisms. Samples were collected from four epidemiological locations in the north, centre and southern regions of Malawi. The diversity and genetic differentiation of P. falciparum populations were analyzed based on the highly polymorphic block 3 msp-2 gene. One hundred and twenty patient samples who presented with signs and symptoms of malaria and who had microscopically confirmed P. falciparum infection were enrolled in the study after they had satisfied the inclusion criteria. Parasite DNA was extracted from the blood spot on to filter paper and analyzed by genotyping the msp-2 gene using allele-specific nested PCR. A total of 28 msp-2 block 3 fragments, defined by the size and the allelic types were detected in the 102 patients. The length variants of the PCR product ranged from 240basepairs (bp) to 450bp for the K1/FC and 410bp to 780bp for the 3D7/IC allelic families. Isolates of the 3D7 alleles were predominant in the population (59 percent), compared to isolates of the K1/ FC27 alleles (41 percent) and for 3D7 and K1 most of the isolates were monoclonal infections. In comparisons between the sites, we observed the highest prevalence of mixed infection in Mwanza (46.7 percent) followed by Dwangwa (23.3 percent) compared to Bolero (16.7 percent) and Mitundu (16.7 percent). The difference in prevalence of mixed infections between Mwanza and the other sites was statistically significant (p=0.041). There was also a non-significant trend towards a higher mean genotype number per isolate in the children aged >5 years compared to those below 5 years of age. These data suggest differences in prevalence rates of mixed infections in different geographical/epidemiological settings in Malawi. Further studies are needed to confirm, with larger sample sizes, the observation of a non-significant trend towards higher multiclonality of infection in older children in malaria endemic areas of Malawi.
35

Influência dos polimorfismos dos genes Mu 1 (GSTM1), Theta 1 (GSTT1), XPD Asp312Asn e XPD Lys751Gln na susceptibilidade ao melanoma cutâneo / Influence of the polymorphisms of genes Mu 1 (GSTM1), Theta 1 (GSTT1), XPD Asp312Asn e XPD Lys751Gln in cutaneous melanoma susceptibility

Rinck Júnior, José Augusto, 1974- 26 August 2018 (has links)
Orientador: Carmen Silvia Passos Lima / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-26T16:24:35Z (GMT). No. of bitstreams: 1 RinckJunior_JoseAugusto_D.pdf: 4925898 bytes, checksum: cf6e78a6e4ad84c7bbe48d34d75fdae6 (MD5) Previous issue date: 2015 / Resumo: As glutationa S-transferases (GSTs) são enzimas detoxificantes. Os genes GSTM1 e GSTT1 são polimórficos e quando deletados perdem a expressão enzimática. As proteínas codificadas pelos genes XPD são responsáveis pelo reparo de lesões do DNA causadas pela luz solar. Polimorfismos nestes genes também podem codificar proteínas com funções comprometidas, em especial o Lys751Gln e o Asp312Asn do gene XPD. Ainda não é claro o papel dos polimorfismos destes genes no risco de melanoma cutâneo (MC) ou se estão associados com os aspectos clínicopatológicos. Foram incluídos 489 indivíduos (231 pacientes, 258 controles). A genotipagem foi realizada por reação em cadeia da polimerase e digestão enzimática. O risco de MC esteve aumentado em 2,00 (IC 95%: 1,05-3,81, P= 0,03) vezes em portadores do genótipo GSTT1 nulo + Asp/Asn + Asn/Asn do XPD Asp312Asn. O GSTT1 nulo elevou o risco de MC metastático em 3,75 (IC 95%: 1,48-9,44, P= 0,006) vezes e se combinado ao GSTM1 nulo em 7,33 (IC 95%: 2,09-25,68, P= 0,003) vezes. O alelo 312Asn elevou o risco de MC no tronco ou membros em 1,80 (IC 95%: 1,19-2,73, P= 0,005) vezes e do subtipo extensivo superficial ou nodular em 1,80 (IC 95%: 1,14-2,84, P= 0,01) vezes. Os genótipos Asn/Asn + Gln/Gln elevou o risco de MC de níveis I, II ou III de Clark em 2,46 (IC 95%: 1,12-5,37, P= 0,02) vezes. Os genótipos GSTM1 nulo + GSTT1 nulo (HR: 3,18; IC95%: 1,21-8,36, P= 0,01) e o genótipo GSTT1nulo + Gln/Gln (HR: 5,93; IC95%: 1,53-22,91, P= 0,01) estiveram associados a maior risco de morte. Concluímos que os referidos polimorfismos em combinações específicas podem aumentar a susceptibilidade ao MC e influenciar suas características clínicopatológicas e sobrevida / Abstract: The glutathione S-transferases (GST) are detoxifying enzymes; the GSTM1 and GSTT1 genes are polymorphic and when deleted lose enzyme expression. The XPD proteins are responsible for DNA damage repair caused by sunlight. Polymorphisms (SNPs) in XPD genes may also result proteins with impaired function, in particular Lys751Gln and Asp312Asn. However It¿s not entirely clear whether the SNPs of these genes influence the risk of cutaneous melanoma (CM) or are associated with clinic pathological aspects of this disease. In the present study 489 individuals were included (231 patients and 258 controls). Genotyping was performed by polymerase chain reaction and enzyme digestion. The risk of MC was increased 2.00-fold (95% CI: 1.05-3.81, P= 0.03) in carriers of the GSTT1 null combined with Asp/Asn + Asn/Asn genotype of XPD Asp312Asn. The GSTT1 null genotype and GSTT1 null + GSTM1 null genotype increased the risk of metastatic MC by 3.75-fold (95% CI: 1.48-9.44, P= 0.006) and 7.33-fold (95% CI: 2.09-25.68, P= 0.003), respectively. The allele 312Asn increased the risk of MC in the trunk or limbs in 1.80-fold (95% CI: 1.19-2.73, P= 0.005) and superficial spreading or nodular subtype in 1.80-fold (95%: 1.14-2.84, P= 0.01). The combined Asn/Asn + Gln/Gln genotype raised the risk of MC in Clark¿s level I, II or III in 2.46-fold (95% CI: 1.12-5.37, P= 0.02). The genotype GSTM1null + GSTT1 null (HR: 3.18; 95% CI: 1.21-8.36, P= 0.01) and GSTT1 null + Gln/Gln (HR: 5.93; 95% CI: 1.53-22.91, P= 0.01) were predictive of lower overall survival. In conclusion, polymorphisms in specific genes combinations may increase susceptibility to MC and influence their clinic pathological features and survival / Doutorado / Clinica Medica / Doutor em Clínica Médica
36

Anxiety and depression: An empirical investigation of the Diathesis-Stress Model of psychopathology

Hartley, Deborah Jean 01 January 1999 (has links)
No description available.
37

The role of the major histocompatibility complex and the Leukocyte receptor complex genes in susceptibility to tuberculosis in a South African population

Salie, Muneeb 04 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Tuberculosis (TB) disease results in approximately 2 million deaths annually and is the leading cause of death due to a single infectious agent. Previous studies have indicated that host genetics play an important role in the development of TB. This together with pathogen and environmental factors intensifies the complexity of this disease. The Major Histocompatibility Complex (MHC) and Leukocyte Receptor Complex (LRC) comprise several genes which are known to be important modulators of the host immune response. The human leukocyte antigen (HLA) class-I genes of the MHC are involved in the presentation of pathogenic antigens on the surfaces of infected cells, while the killer cell immunoglobulin-like receptors (KIRs) of the LRC are involved in the recognition of self and non-self cells. Natural Killer (NK) cells through their KIRs are thus able to kill non-self cells through recognition of the class-I molecules expressed. Additionally, HLAs and KIRs are extremely polymorphic and differ markedly across populations of different ethnicities. Here we studied these genes and their polymorphisms in the South African Coloured (SAC) population to determine their involvement in susceptibility to TB, susceptibility to disease caused by specific Mycobacterium tuberculosis subtypes, and understanding their ancestral contribution to the SAC with regards to the development of TB. We showed that the KIR3DS1 gene and KIR genotypes with five or more activating KIRs, and the presence of 3DS1, protected against the development of active TB in the SAC population. Several HLA class-I alleles were identified as susceptibility factors for TB disease. With regards to genes of the MHC and LRC, several loci were found to alter susceptibility to TB in the SAC population, including MDC1, BTNL2, HLA-DOA, HLA-DOB, C6orf10, TAP2, LILRA5, NCR1, NLRP7 and the intergenic regions between HLA-C/WASF5P and LAIR1/TTYH1. We showed that the Beijing strain occurred more frequently in individuals with multiple disease episodes, with the HLA-B27 allele lowering the odds of having an additional episode. Associations were identified for specific HLA types and disease caused by the Beijing, Latin America-Mediterranean (LAM), Low-Copy Clade (LCC), and Quebec strains. HLA types were associated with disease caused by strains from the Euro-American or East Asian lineages, and the frequencies of these alleles in their sympatric human populations identified potential co-evolutionary events between host and pathogen. Finally, we showed that the SAC population is the most diverse SA population with regards to HLA alleles and KIR genotypes, as would be expected given the admixture of the SAC. Based on the HLA allele class-I profiles across SA populations, we noted that the Ag85BESAT- 6, Ag85B-TB10.4 and Mtb72f vaccines currently undergoing clinical trials would have low efficacy across most SA populations. We showed that the MHC and LRC regions in SAC healthy controls are predominantly of European ancestry, and that SAC TB cases are more closely related to Khoisan and black SA population groups. Our work highlights the importance of investigating both host and pathogen genetics when studying TB disease development and that understanding the genetic ancestral contributions to the SAC population can contribute to the identification of true and novel TB causing variants. / AFRIKAANSE OPSOMMING: Tuberkulose (TB) is jaarliks verantwoordelik vir ongeveer 2 miljoen sterftes en is die hoofoorsaak van dood as gevolg van „n aansteeklike siekte. Vorige navorsingstudies het aangedui dat die genetiese samestelling van die gasheer „n beduidende rol speel in die ontwikkeling van TB. Die kompleksiteit van hierdie siekte word vererger deur die betrokkenheid van die gasheer genoom sowel as bakteriële en omgewings faktore. Die Major Histocompatibility Complex (MHC) en Leukocyte Receptor Complex (LRC) bestaan uit verskeie gene wat die gasheer immuunrespons verstel. Die human leukocyte antigen (HLA) klas I gene van die MHC is betrokke by die aanbieding van patogeniese antigene op die oppervlak van geïnfekteerde selle, terwyl die killer cell immunoglobulin-like receptors (KIRs), geleë in die LRC, betrokke is by die herkenning van eie en vreemde selle. NK selle, deur middel van hul KIRs, kan dus vreemde selle uitwis aangesien hulle die uitgedrukte klas I molekules kan herken. Beide HLA en KIRs is hoogs polimorfies en verskil beduidend tussen etniese groepe. In hierdie studie is die bogenoemde gene en hul polimorfismes in die Suid Afrikaanse Kleurling bevolking (SAC) ondersoek om vas te stel tot watter mate dit genetiese vatbaarheid vir TB, asook vatbaarheid vir TB wat deur spesifieke Mycobacterium tuberculosis subtipes veroorsaak word, beïnvloed. Daar is ook gepoog om te verstaan hoe die voorouerlike bydrae van hierdie gene die SAC met betrekking tot TB vatbaarheid affekteer. Die resultate van die studie het aangedui dat die KIR3DS1 geen en KIR genotipes met vyf of meer aktiewe KIRs en die teenwoordigheid van 3DS1, die SAC bevolking beskerm teen die ontwikkeling van aktiewe TB. Verskeie HLA klas I allele is geïdentifiseer as vatbaarheidsfaktore vir TB. Talle lokusse van die MHC en LRC gene is ook as vatbaarheidsfaktore vir TB in die SAC bevolking geïdentifiseer, insluitende MDC1, BTNL2, HLA-DOA, HLA-DOB, C6orf10, TAP2, LILRA5, NCR1, NLRP7 en die intergeniese areas tussen HLA-C/WASF5P en LAIR1/TTYH1. Die studie het aangedui dat die Beijing stam meer voorkom in individue wat verskeie kere TB gehad het en dat die HLA-B27 alleel die kanse om „n verdere episode te hê, verlaag het. Assosiasies is geïdentifiseer tussen spesifieke HLA tipes en siekte veroorsaak deur die Beijing, LAM, LCC, en Quebec TB stamme. HLA tipes was geassosieer met siekte veroorsaak deur TB stamme van Euro-Amerikaanse en Oos-Asiëse afkoms. Die frekwensies van hierdie allele, in hul ooreenstemmende mensbevolkings, dui op „n potensïele koevolusionêre gebeurtenis tussen die gasheer en patogeen. Die studie het ook vasgestel dat die SAC populasie die mees diverse SA bevolking is met betrekking tot die HLA allele en KIR genotipes, soos verwag sou word gegewe die gemengde genetiese herkoms van die SAC. Gebaseer op die HLA allele klas I profiel van verskillende SA bevolkings merk ons op dat die Ag85B-ESAT-6, Ag85B-TB10.4 en Mtb72f vaksiene, wat huidiglik kliniese toetsing ondergaan, nie so effektief in die meeste SA bevolkings sal wees nie. Die studie het ook bewys dat die MHC en LRC streke in gesonde SAC kontroles, grootliks afkomstig was van „n Europese nalatenskap en dat die SAC TB gevalle meer verwant is aan die Khoisan en swart SA bevolkings. Hierdie studie beklemtoon die noodsaaklikheid om beide gasheer en patogeen genetika te bestudeer wanneer die ontwikkeling van TB ondersoek word en dat die verstaan van die genetiese voorouerlike bydrae van die SAC bevolking kan bydra tot die identifisering van ware en nuwe TB-veroorsakende variante.
38

Identification of candidate genes that influence sex hormone dependent disease phenotypes in mouse lupus /

Gubbels, Melanie Rae. January 2005 (has links)
Thesis (Ph.D. in Human Medical Genetics) -- University of Colorado at Denver and Health Sciences Center, 2005. / Typescript. Includes bibliographical references (leaves 104-138). Free to UCDHSC affiliates. Online version available via ProQuest Digital Dissertations;
39

Desenvolvimento de metodologia para imobilização de dípteros e avaliação de adulticidas : validação com mosquitos (Diptera: Culicidae) e moscas (Diptera: Chloropidae) / Development of methodology to immobilization of dipteras and evaluation of adulticides : validation with mosquitoes (Diptera: Culicidae) and flies (Diptera: Chloropidae)

Cabrini, Isaías, 1978- 31 January 2013 (has links)
Orientador: Angelo Pires do Prado / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-22T01:14:59Z (GMT). No. of bitstreams: 1 Cabrini_Isaias_D.pdf: 2849716 bytes, checksum: ed08a0c88dd0e1b75d716f1c4b64e9ff (MD5) Previous issue date: 2013 / Resumo: Métodos para controlar e monitorar a susceptibilidade de insetos vetores tem sido estudado. Órgãos governamentais como World Health Organization (WHO) e Center of Disease Control (CDC) tem preconizado metodologias de bioensaios para avaliação em laboratório de resistência de mosquitos. O objetivo para se realizar testes de susceptibilidade é detectar a presença de indivíduos resistentes em uma população de inseto para que se possa, tão logo quanto possível, iniciar planos de controle alternativo, evitando-se assim os custos adicionais e problemas na redução da população do vetor. No entanto, alguns aspectos de tais metodologias são questionáveis e podem comprometer a metodologia como eficaz para revelar se uma população está resistente a um determinado inseticida. Por exemplo: 1) o Método do Papel Impregnado (WHO) possui algumas desvantagens como alto custo do material, falhas no contado do mosquito com a superfície tratada e possibilidade de perda de indivíduos durante o manuseio dos equipamentos; 2) O Método de Atividade Intrínseca do Inseticida (WHO) propõe a utilização de CO2 e baixa temperatura para anestesiar os mosquitos e acetona como diluente e aplicação do inseticida com um micro-capilar que proporciona gotas de 0,1 ?L. No entanto, os meios de anestesia levam ao estresse fisiológico, a baixa temperatura retarda a evaporação da acetona e o micro-capilar não libera o volume correto de solução e; 3) o Método da Garrafa Impregnada (CDC) permite que os mosquitos recebam o inseticida apenas pelo contato tarsal e dessa forma a quantidade de inseticida recebida pelo inseto pode não ser letal. O presente trabalho teve como objetivo desenvolver uma metodologia que eliminasse tais desvantagens. Foi possível demonstrar que a exposição de machos e fêmeas de Aedes aegypti ao CO2, baixa temperatura ou ambos, leva a uma mortalidade significativa. Um método de imobilização por meio de sucção foi desenvolvido, utilizando-se um aspirador de pó portátil. Esse método permitiu a imobilização de mosquitos e moscas (Chloropidae), havendo uma baixa mortalidade de mosquitos apenas após 60 min. de permanente imobilização, concluindo-se que o método de imobilização por sucção pode substituir os métodos de anestesia. Um método de aplicação líquida foi proposto, utilizando-se dispersores utilizados para aplicação de perfume, sendo que um dos parâmetros avaliados foi o tamanho de gotas. Os resultados demonstraram que é possível a utilização desses dispersores para aplicação de inseticida, pois há homogeneidade no tamanho das gotas. Utilizando esse método de aplicação, avaliou-se a possibilidade de utilização de acetona ou álcool etílico como diluente de inseticidas, sendo que a acetona causou alta mortalidade em fêmeas e machos de Ae. aegypti e dessa forma foi proposto à utilização de álcool etílico. A metodologia aqui proposta foi utilizada para análise de susceptibilidade do mosquito Aedes aegypti (Culicidae) e mosca Liohippelates nigrifons (Chloropidae) aos inseticidas malation e deltametrina. Foi possível estabelecer a linha base de susceptibilidade, a CL50 e a concentração diagnóstico. Além disso, foi possível detectar a resistência de uma população de Ae. aegypti advinda do campo. Conclui-se que a metodologia de imobilização associada ao método de aplicação líquida pode ser utilizada para detecção de resistência de mosquitos / Abstract: Methods to control and monitor the susceptibility of vectors has been studied. Government agencies like World Health Organization (WHO) and Centers for Disease Control (CDC) has recommended methodologies bioassays for evaluating resistance in mosquitoes in the laboratory. The goal is to perform susceptibility testing is to detect the presence of resistant individuals in a population of insects so that we can, as soon as possible, initiate alternative control plans, thus avoiding additional costs and problems in reducing the vector population. However, some aspects of these methodologies are questionable and may denigrate as effective methodology to find out if a population is resistant to a particular insecticide. For example: 1) Method of Impregnated Paper (WHO) has some disadvantages such as high cost of material failures counted mosquito with the treated surface and the possibility of loss of individuals during handling equipment, 2) The Method of Intrinsic Activity of Insecticide (WHO) proposes the use of CO2 and low temperature to anesthetize mosquitoes and acetone as diluents and insecticide application with a micro-capillary that provides drops of 0.1 ?l. However, the means of anesthesia leading to physiological stress, low temperature retards the evaporation of acetone and the micro-capillary will not release the correct volume of solution, and 3) the method of Impregnated bottle (CDC) enables receiving mosquito insecticide only by tarsal contact and thus the amount of insecticide received by the insect cannot be sufficiently lethal. This study aimed to develop a methodology that would eliminate such disadvantages. It was possible to demonstrate that exposure of male and female Aedes aegypti CO2, low temperature, or both leads to a significant mortality. A method of immobilization by suction was developed using a portable vacuum cleaner. This method allowed for the immobilization of mosquitoes and flies (Chloropidae), having a low mosquito mortality after only 60 min. permanent immobilization, concluding that the immobilization method by suction can override the methods of anesthesia. A liquid application method was proposed, using disperser's perfume, and one of the parameters evaluated droplet size. The results demonstrated that it is possible to use the dispersers for insecticide application, as there uniformity in droplet size. Using this application method, we evaluated the possibility to use acetone or ethanol as diluents insecticides, and acetone caused high mortality in female and male Ae. aegypti and thus it was proposed to use alcohol. The methodology proposed here was used to analyze the susceptibility of the mosquito Aedes aegypti (Culicidae) and fly Liohippelates nigrifons (Chloropidae) to insecticides Malathion and Deltamethrin. It was possible to establish baseline susceptibility, and the LC50 concentration diagnosis. Moreover, it was possible to detect the resistance of an Ae. aegypti originating from the field. It is concluded that the method of immobilization associated liquid application method can be used to detect resistance of mosquitoes / Doutorado / Parasitologia / Doutor em Parasitologia
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Genomic Analysis of Acropora cervicornis Mucus and Sediments in the Florida Keys Tavernier Nursery

Zimmerman, Rachel 13 August 2018 (has links)
White Band disease has devastated the staghorn coral Acropora cervicornis in recent decades, and it continues to impinge upon restoration efforts. The etiological agent(s) remain unknown as Koch’s postulates have yet to be satisfied, but disease may originate when opportunistic pathogens in the surface mucus layer exploit a stressed host. Using 16s rRNA sequencing, differences in the taxonomic diversity and relative abundances of bacteria within the mucus of A. cervicornis were documented between colonies of the same genotype, genotypes (n=8) categorized as having either high or low WBD susceptibility, and during a transplantation event. A. cervicornis colonies suspended from midwater PVC trees via monofilament were sampled for mucus, after which half of the sampled colonies were relocated to the unconsolidated sediments below. Temporal changes in the microbiome of the pelagic and benthic corals were then monitored by sampling the same apical tip over time. Incidentally, all benthic colonies for this experiment became afflicted with WBD; thereby differences in healthy vs. diseased colonies and the effects of disease progression on the microbiome were documented. Water was sampled concurrently with all mucus experiments to resolve the degree of commonality in bacterial species between the two environments, and sediments were sampled in the transplant experiment to determine if sediments may act as a pathogen reservoir. In addition, sediment samples were collected to assess site and temporal differences in the benthic microbiome along a nearshore to offshore transect off Key Largo, Florida. Irrespective of the inclusion of water operational taxonomic units (OTUs), no differences between colonies of the same genotype were observed with regards to the bacterial communities sampled from mucus in either alpha diversity metrics [species richness, Shannon, Inverse Simpson] or phylogenetic relatedness as determined by weighted unique fraction (UniFrac) were detected between colonies. However, differences were observed in the Bray-Curtis dissimiliarity matrices based on relative abundance and presence/absence of either [with and without water OTU] scenarios. Bacterial communities associated with different coral genotypes differed in species richness and Inverse Simpson in both water scenarios, as did weighted UniFrac and Bray-Curtis relative abundance and presence/absence transformed dissimilarity matrices. Alpha diversity of mucus bacteria was similar between corals of different disease-susceptibilities when water OTUs were either included or excluded, except for the Inverse Simpson index upon removal of water OTUs. Removal of aqueous bacteria also revealed significant differences between disease-susceptibility groups in Bray-Curtis relative abundance and presence/absence dissimiliarity values that was not detected with the incorporation of water OTUs. Regardless of the presence of water OTUs, weighted UniFrac was similar between corals of different disease susceptibilities. Most notably, dispersion increased in the microbiome of coral genotypes with high disease susceptibility in all cases except for the relative abundance transformed Bray-Curtis dissimilarity matrix when water OTUs were incorporated. This finding is in accordance with the Anna Karenina Principle, which states that loss of microbial regulation leads to an unpredictable microbiome in diseased individuals. In the sediment experiment, location was the only factor influencing microbiome composition. These findings may be due to the short duration of the experiment and differences between the carbonate content of the sediments and hydrological regimes between sites.

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