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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.
41

Bayesian Lasso for Detecting Rare Genetic Variants Associated with Common Diseases

Zhou, Xiaofei 23 October 2019 (has links)
No description available.
42

Análise comparativa entre os genomas dos fitopatógenos Xylella fastidiosa e Xanthomonas axonopodis pv. citri / Comparative analysis between the genomes of the phytopathogens Xylella fastidiosa and Xanthomonas axonopodis pv. citri

Moreira, Leandro Marcio 04 November 2002 (has links)
Xylella fastidiosa (Xf) e Xanthomonas axonopodis pv. citri (Xac) são gama proteobactérias gram negativas, responsáveis por grandes perdas econômicas no setor citrícola brasileiro. Com seus genomas seqüenciados e anotados, fizemos uma análise comparativa entre suas composições gênicas e seus ambientes de vida. Xac apresenta um genoma de 5.2Mb contra 2.7Mb de Xf Isto reflete no número de genes (4432 contra 2838) que acabam refletindo em uma maior complexidade metabólica de Xac, caracterizada por: uma extensa gama de genes de degradação de parede celular (44), biossíntese de proteases (92), genes de funções regulatórias (296), um completo metabolismo energético (209), quimiotático (inexistente em Xf) e secretório (presença dos tipos I, II, III e IV , sendo o II em duplicata), além de um grande número de genes envolvidos com captação de ferro (65), fazem de Xac um patógeno de alto poder invasivo e de rápida propagação e virulência Em contrapartida, Xf por não possuir a complexidade supracitada, parece ter seus recursos adaptados ao ambiente em que vive, como por exemplo um alto número de genes envolvidos com biossíntese de pili, que associado à biossíntese de goma, favorecem sua adesão nas glândulas salivares do vetor (cigarrinha) e a formação de aglomerados celulares responsáveis pelo entupimento dos vasos que levam às patologias decorrentes do evento. / Xylella fastidiosa (Xf) and Xanthomonas axonopodis pv. citri Xac are gram negative gamma proteobacteria, responsible for great economical losses in the Brazilian citrus sector. With their sequenced and annotated genomes, we have done a comparative analysis between their genetic composition and life habitat. Xac displays a genome of 5.2Mb against 2. 7Mb of Xf. This reflects the number of genes (4432 against 2838) which results in a greater metabolic complexity of Xac, characterized by: a wide range of genes of cell wall degradation (44), biosynthesis of proteases (92), many genes of regulatory functions (296), a complex energy metabolism (209), chemotatic (absent in Xf) and secretory systerns (presence of types I, II, III and IV, type II in duplicate), besides a great number of genes involved in iron acquisition (65), make of Xac a pathogen of high invasive power and of quick spreading and virulence. In the other hand Xf, due to the lack of the complexity just cited, seems to have its resources adapted to the habitat in which it lives, as for example a large number of genes involved in pili biosynthesis, that associated with gum biosynthesis, favor its adhesion to the salivary glands of the vector (sharpshooter) and the formation of cellular agglomerations responsible for the blockage of the vessels which leads to the pathologies resulted from this event.
43

Análise comparativa entre os genomas dos fitopatógenos Xylella fastidiosa e Xanthomonas axonopodis pv. citri / Comparative analysis between the genomes of the phytopathogens Xylella fastidiosa and Xanthomonas axonopodis pv. citri

Leandro Marcio Moreira 04 November 2002 (has links)
Xylella fastidiosa (Xf) e Xanthomonas axonopodis pv. citri (Xac) são gama proteobactérias gram negativas, responsáveis por grandes perdas econômicas no setor citrícola brasileiro. Com seus genomas seqüenciados e anotados, fizemos uma análise comparativa entre suas composições gênicas e seus ambientes de vida. Xac apresenta um genoma de 5.2Mb contra 2.7Mb de Xf Isto reflete no número de genes (4432 contra 2838) que acabam refletindo em uma maior complexidade metabólica de Xac, caracterizada por: uma extensa gama de genes de degradação de parede celular (44), biossíntese de proteases (92), genes de funções regulatórias (296), um completo metabolismo energético (209), quimiotático (inexistente em Xf) e secretório (presença dos tipos I, II, III e IV , sendo o II em duplicata), além de um grande número de genes envolvidos com captação de ferro (65), fazem de Xac um patógeno de alto poder invasivo e de rápida propagação e virulência Em contrapartida, Xf por não possuir a complexidade supracitada, parece ter seus recursos adaptados ao ambiente em que vive, como por exemplo um alto número de genes envolvidos com biossíntese de pili, que associado à biossíntese de goma, favorecem sua adesão nas glândulas salivares do vetor (cigarrinha) e a formação de aglomerados celulares responsáveis pelo entupimento dos vasos que levam às patologias decorrentes do evento. / Xylella fastidiosa (Xf) and Xanthomonas axonopodis pv. citri Xac are gram negative gamma proteobacteria, responsible for great economical losses in the Brazilian citrus sector. With their sequenced and annotated genomes, we have done a comparative analysis between their genetic composition and life habitat. Xac displays a genome of 5.2Mb against 2. 7Mb of Xf. This reflects the number of genes (4432 against 2838) which results in a greater metabolic complexity of Xac, characterized by: a wide range of genes of cell wall degradation (44), biosynthesis of proteases (92), many genes of regulatory functions (296), a complex energy metabolism (209), chemotatic (absent in Xf) and secretory systerns (presence of types I, II, III and IV, type II in duplicate), besides a great number of genes involved in iron acquisition (65), make of Xac a pathogen of high invasive power and of quick spreading and virulence. In the other hand Xf, due to the lack of the complexity just cited, seems to have its resources adapted to the habitat in which it lives, as for example a large number of genes involved in pili biosynthesis, that associated with gum biosynthesis, favor its adhesion to the salivary glands of the vector (sharpshooter) and the formation of cellular agglomerations responsible for the blockage of the vessels which leads to the pathologies resulted from this event.
44

Genetičke i morfometrijske karakteristike dva tipa kranjske pčele / Genetic and morphometric caracteristics of two types of cornual bees

Pihler Ivan 12 April 2012 (has links)
<p>Morfometrijske analize su ra&ntilde;ena merenjem krilne nervature 540 uzoraka krila<br />pčela sa 9 lokaliteta u Vojvodini. Izračunato je 16 uglova (A1, A4, B3, B4, D7, E9, G7,<br />G18, H12, J10, J16, K19, L13, M17, O26, Q21) koje zaklapa krilna nervatura i 4 indeksa<br />(Ci, Pci, Dbi, Ri), ukupno 20 mera. Izračunate su prosečne vrednosti i utvr&ntilde;ena je<br />statistička značajnost razlika izme&ntilde;u pčela iz regona Srema i Bačke i pčela iz regiona<br />Banata, tako&ntilde;e je izvr&scaron;eno i pore&ntilde;enje pčela svih lokaliteta sa DAWINO standardima za<br />5 rasa pčela (Apis mellifera carnica, Apis mellifera macedonica, Apis mellifera mellifera,<br />Apis mellifera ligustica i Apis mellifera caucasica).<br />Analizom varijanse izračunatih 20 osobina krilne nervature, utvr&ntilde;eno je da samo<br />kod osobine A4 nisu utvr&ntilde;ene statistički značajnie razlike izme&ntilde;u posmatranih<br />lokaliteta, dok su u 19 osobina utvr&ntilde;ene statistički značajne razlike.<br />Utvr&ntilde;ivanjem statističke značajnosti razlika, pčela iz regiona Srema i Bačke i pčela<br />iz regiona Banata, utvr&ntilde;eno je da 45% osobina ne pokazuju statistički značajne razlike,<br />dok 45% osobina pokazuje statistički vrlo značajne razlike (P&lt;0,01) i 10% osobina<br />pokazuje statistički značajne razlike (P&lt;0,05).<br />Upore&ntilde;ivanjem dobijenih vrednosti 20 parametera krilne nervature, pomoću ztesta,<br />sa DAWINO standardima za pet rasa pčela, utvr&ntilde;eno je da na bazi celog uzorka<br />statistički nema značajnih razlika kod osobina A4 i D7 sa A. m. carnica, kod osobina<br />H12, G18 i B4 sa A. m.macedonica i kod osobina J16 i B4 pore&ntilde;eno sa rasom A.<br />m.ligustica. Kod pčela iz regiona Srema i Bačke utvr&ntilde;eno je da statistički nema značajnih<br />razlika kod osobina A4, B3, D7 i G18 upore&ntilde;eno sa A.m. carnica, kod osobina H12 i B4<br />upore&ntilde;eno sa A. m.macedonica i kod osobina G18, K19, J16 i Q21 upore&ntilde;eno sa rasom<br />A. m.ligustica, dok kod pčela iz regiona Banata utvr&ntilde;eno je da statistički nema značajnih<br />razlika kod osobina A4, E9, D7 i J10 upore&ntilde;eno sa A.m. carnica, kod osobina H12, J10,<br />L13 i PCi upore&ntilde;eno sa A. m.macedonica i kod osobina B4, J16 i PCi upore&ntilde;eno sa<br />rasom A. m.ligustica.<br />Ocena genetičke povezanosti, unutar populacijska raznolikost i struktura<br />populacije, dva tipa pčela u Vojvodini, izračunata je na bazi varijacije alela 25 lokusa<br />mikrosatelita. Izvr&scaron;ena je genetska tipizacija sledećih mikrosatelita: A8, A14, A24, A29,<br />A43, A79, A88, A113, Ac11, Ac88, Ac139, Ac306, Ap15, Ap68, Ap85, Ap90, Ap223,<br />Ap224, Ap226, Ap249, Ap273, Ap274, Ap288, At168, At188. 92% ili 23 lokusa su se<br />pokazali kao polimorfni u uzorcima pčela iz Srema i Bačke, a 88% ili 22 lokusa su se<br />pokazali kao polimorfni u uzorcima pčela iz Banata. Izračunata heterozigotnost na nivou<br />cele populacije se nije statistički značajno razlikovala od očekivane heterozigotnosti.<br />Utvr&ntilde;eno je da dobijene genetičke razlike izme&ntilde;u analiziranih pčela iz regiona Srema i<br />Bačke i retgiona Banata nisu dovoljne da se ove dve populacije mogu smatrati<br />razdvojenim.</p> / <p> Morphometric analyses have been done by measuring the wing nervature in<br /> 540 samples of bees, collected from nine localities in Vojvodina. 16 angles<br /> formed by wing nervation have been calculated(A1, A4, B3, B4, D7, E9, G7,<br /> G18, H12, J10, J16, K19, L13, M17, O26, Q21) as well as four indexes (Ci, PCI,<br /> DBI , R), a total of 20 measures. The average values have been calculated and<br /> statistical significant differences in bees from Srem, Backa and Banat region<br /> determined. Five breeds of bees from these regions have been compared to<br /> Dawino standards.<br /> The analyses of the variance of calculated 20 features of wing nervature indicate<br /> that statistically significant differences in monitored localities have not been found<br /> only in A4, on the other hand in 19 properties significant differences have been<br /> discovered.<br /> Established statistically significant differences between breeds from Srem<br /> and Backa regions reveale that 45% properties do not show any statistically<br /> important differences, while 45% features show very important statistical<br /> differences (P&lt;0,01) and 10% show statistically important differences (P&lt;0,05).<br /> It has been established by comparing the obtained values of 20 parametres<br /> of wing nervature by means of z test to DAWINO standards for five breeds of<br /> bees that, based on the whole sample, there are no significant differences in<br /> features A4 and D7 in A.m. carnica, in features H12, G18 and B4 in A.m.<br /> macedonica and features J16 and B4 compared to A.m. ligustica. As for bees from<br /> Srem and Backa region,there are statistically no significante differences in<br /> features A4, B3, D7 and G18 compared to A.m. carnica, features H12 and B4<br /> compared to A.m. macedonica and features G18, K19, J16 and Q21 compared to<br /> A.m. ligustica, while in bees from Banat region, statistically there are no<br /> significant differences in features A4, E9, D7 and J10 compared to A.m. carnica,<br /> features H12, J10, L13 and Pci compared to A.m. macedonica and features B4,<br /> J16 and Pci compared to A.m. ligustica.<br /> The evaluation of genetic correlation, the diversity of bees population and<br /> population structure of two types of bees in Vojvodina have been established on<br /> the basis of allels variations in 25 locus microsatelites.The following<br /> microsatelites have been standardized &ndash; A8,A14,A24,A29, A43, A79, A88, A113,<br /> Ac11, Ac88, Ac139, Ac306, Ap15, Ap68, Ap85, Ap90, Ap223, Ap224, Ap226,<br /> Ap249, Ap273, Ap274, Ap288, At168, At188. 92% or 23 locus have shown as<br /> polymorphs in bees from Srem and Backa and 88% or 22 locus samples have<br /> shown as polzmorphs in bees samples from Banat and Backa region. The whole<br /> population calculated heterozygosity has not shown statistically significant<br /> differrence from expected heterozygisity. It has been established that the obtained<br /> genetic differences between the analysed bees from Srem and Backa region and<br /> Banat region are not significant to indicate two populations.</p>
45

IRINOTECANTOXICITY RELATED TO GILBERT´S SYNDROME   - COMPARISON OF THREE METHODS FOR GENOTYPING OF UGT1A1 (TA)<sub>n</sub>

Fredriksson, Lena January 2009 (has links)
<p>Gilbert’s syndrome (GS) occurs in approximately 10% of the European population. The most common cause is homozygosity for UGT1A1*28, which is a TA repeat expansion in the promoter of UGT1A1. It is characterised by intermittent hyperbilirubinemia due to reduced hepatic activity of the  enzyme UDP-glucuronosyl-transferase 1A1(UGT1A1). GS also  alteres the pharmacokinetics of some drugs and increases the risk of drug toxicity. Irinotecan (Camptosar®, Campto®) is used in metastatic colorectal cancer and the active metabolite is inactivated by UGT1A1. Studies have shown that GS can be a risk factor for toxicity during irinotecan therapy.</p><p>Three different methods for genotyping of UGT1A1*28 have been tested.</p><p>PCR with electrophoresis used for size separation, melting temperature analysis and fluorescent PCR followed by fragment analysis on a capillary sequencer.</p><p>The last method was found to be superior. This method was used for genotyping of patients with colorectal cancer treated with irinotecan and 5-fluorouracil in the Nordic VI study. A significant association between UGT1A1 genotype and plasma bilirubin level before the start of irinotecan treatment was seen (ANOVA p<0.0001). Patients with GS had an overall increased risk of adverse drug reactions (Fishers Exact test p=0.02).</p><p>Gilbert’s syndrome can be diagnosed by genotyping UGT1A1*28 with a fragment analysis method. Genotyping of UGT1A1*28 can be used to identify patients with an increased risk of adverse reactions to irinotecan.<strong> </strong></p><p><strong> </strong></p> / <p>Gilberts syndrom (GS) drabbar upp till 10% av befolkningen i Västeuropa. GS beror på nedsatt aktivitet av enzymet UDP-glukuronosyltransferas 1A1 (UGT1A1) i levern. Den vanligaste orsaken är att individen är homozygot för en insertion av två baser i promotorn för genen UGT1A1. Denna genvariant kallas (TA)7TAA  eller UGT1A1*28. GS leder till intermittent stegring av bilirubin vid infektioner, men bilirubinstegring kan förekomma även utan utlösande agens. GS kan också leda till bilirubinstegring vid viss läkemedelsbehandling. Irinotekan (Campto®) används vid metastaserande colorektal cancer och dess aktiva metabolit inaktiveras av UGT1A1. Det finns rapporter om att GS ger ökad risk för toxiska biverkningar av irinotekan.</p><p>Tre metoder för att bestämma UGT1A1 har jämförts: PCR med elfores, PCR med smältpunktsanalys och PCR med fragmentanalys på sekvensator. Den sista metoden var bäst och användes för att genotypa UGT1A1 hos patienter med colorektal cancer från Nordic VI-studien. De behandlades med irinotekan i kombination med bolusinjektion eller infusion av 5-fluorouracil. Vi fann att  patienter med GS hade signifikant högre S-bilirubin före behandling jämfört med övriga patienter. De hade även ökad frekvens biverkningar av irinotekan (Fishers exakta test p=0,02).</p><p>Genotypning av UGT1A1 kan således användas för att diagnostisera Gilberts syndrom hos patienter med oförklarad bilirubinstegring. Det kan även användas för att identifiera patienter med ökad risk för biverkningar av irinotekan.</p>
46

Genetic analysis of murine malaria

Campino, Susana January 2003 (has links)
Malaria, an infectious disease caused by Plasmodium parasites, is one of the major world-scale health problems. Despite the efforts aimed at finding an effective way to control the disease, the success has been thwarted by the emergence of parasite drug resistance and mosquito resistance to insecticides. This thesis focuses on the genetic analysis of resistance to murine malaria induced by the lethal Plasmodium berghei ANKA using a wild-derived-inbred strain (WDIS). The aim of this thesis was to exploit the genetic diversity represented among WDIS for identifying loci contributing to resistance/susceptibility to murine malaria. The work included a genome-wide polymorphism survey using microsatellite markers performed on 10 WDIS. Comparisons of these strains to laboratory inbred strains confirmed a higher rate of polymorphism among the WDIS. We conclude that these WDIS represent repositories of unique naturally occurring genetic variability that may prove to be invaluable for the study of complex phenotypes. Next, we used the WDIS to search for novel phenotypes related to malaria pathogenesis. Whereas most laboratory strains were susceptible to experimental cerebral malaria (ECM) after infection with P. berghei ANKA, several WDIS were found to be resistant. To study the genetic inheritance of resistant/susceptibility to P. berghei ANKA infection we analysed backcross and F2 cohorts derived from crossing the WLA wild-derived strain with a laboratory mouse strain (C57BL/6). A novel phenotype represented by the cure of infection, clearance of parasitaemia and establishment of immunological memory was observed in the F2 progeny. The backcross progeny was used to genetically map one locus on chromosome 1 (Berr1) and one locus on chromosome 11 (Berr2) that mediate control of resistance to ECM induced by P. berghei ANKA. Genetic mapping using the F2 progeny showed that a locus on chromosome 1 (Berr1) and a locus on chromosome 9 (Berr3) were contributing to control survival time after infection with lethal Plasmodium. Finally, we identified, a locus on chromosome 4 (Berr4) that appears to control time of death due to hyperparasitaemia. This thesis underlines the value of using WDIS to reveal genetic factors involved in the aetiology of disease phenotypes. The characterisation of the genetic factors represented by the malaria resistance loci identified here are expected to provide a better understanding of the malaria pathology.
47

Iron and Tuberculosis pathogenesis

Cowie, Danielle 04 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Iron is an essential element that plays a role in the process of respiration, oxygen transport and as a principle cofactor to several enzymes. Iron homeostasis is a finely regulated process since excess levels become toxic to healthy cells via the production of reactive oxygen species. A plethora of genes that control several key points throughout this regulatory process have been identified. Research focusing on changes in expression levels and downstream functional effects of these genes has become increasingly important over the past decade. One area of particular interest has emerged since a link between iron status and host response to Mycobacterium tuberculosis infection was discovered. Although the prevalence of Tuberculosis has decreased across the globe with the exception of Africa and parts of Europe, the mortality rate remains high. Therefore, research that focuses on understanding an individual’s predetermined susceptibility to TB infection at the genetic level could provide health care practitioners with the tools required to identify and educate at-risk individuals prior to TB infection. RT-qPCR was utilised to determine expression profiles for eight iron genes (CP, CYBRD1, FTH, FTL, LTF, HFE, HMOX1, and SCL40A1) normalised to three reference genes (ACTB, GUSB, and RPL37A1). Up-regulation is demonstrated in the TB group for transcript levels recorded for CYBRD1, HFE, HMOX1, and SLC40A1. Several measured serum parameters including conjugated, unconjugated, total bilirubin, and total protein were increased in the TB group while albumin was significantly lower in this group. Correlation analysis demonstrated that a positive correlation exists between transferrin saturation and iron and a negative correlation exists between transferrin and ferritin levels. Individuals categorised with low serum iron levels demonstrated lower CP/GUSB levels and higher HMOX1/GUSB levels. Individuals categorised with low transferrin saturation levels demonstrated higher FTL/GUSB and SLC40A1/GUSB levels and lower CP/GUSB. Results from this study provide further evidence for the relationship between iron status and TB infection rates, although protein studies are required to confirm these results. The data obtained illustrate the important role that these profiles and iron parameters may play in the clinical field when identifying at-risk individuals. Further investigation that focuses on which gene profile and parameter combinations show the most distinctive utility in the clinical setting is warranted. / AFRIKAANSE OPSOMMING: Yster is ‘n noodsaaklike element wat ‘n rol speel in die proses van respirasie en die vervoer van suurstof en ook ‘n belangrike ko-faktor vir verskeie ensieme is. Yster homeostase is op ‘n fyn manier gereguleer omdat oormatige vlakke toksies kan wees vir gesonde selle wanneer reaktiewe suurstofspesies geproduseer word. ‘n Magdom gene wat verskeie sleutelpunte in hierdie proses kontroleer is voorheen identifiseer. Navorsing wat fokus op die veranderinge in geenuitdrukkingsvlakke en die funksionele gevolge daarvan het oor die afgelope dekade toenemend belangrik geword. Een gebied van spesifieke belang het na vore gekom nadat ‘n verband tussen ystervlakke en die manier waarop die immuunstelsel reageer op Mycobacterium tuberculosis infeksie, ontdek is. Alhoewel die voorkoms van Tuberkulose wêreldwyd, behalwe in Afrika en sekere dele van Europa, afgeneem het, bly die sterftesyfer hoog. Daarom kan navorsing wat daarop fokus om ‘n individu se voorafbepaalde vatbaarheid vir TB-infeksie op die genetiese vlak te verstaan dalk aan gesondheidswerkers die regte instrumente verskaf om hoë-risiko individue te identifiseer en op te voed voordat hulle TB ontwikkel. RT-qPKR is gebruik om die geenuitdrukkingsvlakke van agt ystergene, wat met drie verwysings-gene (ACTB, GUSB, en RPL37A1) genormaliseer is, te bepaal. ‘n Toename in die uitdrukkingsvlakke van CYBRD1, HFE, HMOX1, en SLC40A1 is in die TB-groep waargeneem. Die bloedvlakke van verskeie parameters insluitend gekonjugeerde, ongekonjugeerde, totale bilirubin, en totale proteïen was hoër in die TB-groep, terwyl albuminvlakke laer was in hierdie groep. Korrelasie-analise het ‘n positiewe korrelasie tussen transferrin-versadiging en yster getoon, terwyl daar ‘n negatiewe korrelasie tussen transferrin- en ferritinvlakke gevind is. Individue met lae ystervlakke het laer CP/GUSB-vlakke en hoër HMOX1/GUSB-vlakke getoon. Individue met lae transferrin-versadiging het hoër FTL/GUSB- en SLC40A1/GUSB-vlakke en laer CP/GUSB-vlakke getoon. Resultate uit hierdie studie verskaf verdere getuienis dat daar ‘n verwantskap tussen ystervlakke en TB-infeksiekoerse bestaan, alhoewel proteïenstudies nodig is om hierdie resultate te bevestig. Die data dui op die belangrike rol wat hierdie profiele en ystervlakke in die kliniese veld mag speel in die identifisering van hoë-risiko individue. Verdere ondersoek, gefokus op watter geenprofiel en parameterkombinasies die grootste nut in die kliniese omgewing bied, is geregverdig.
48

Microgenetic Analysis of Moral Development: Theoretical and Methodological Issues / El análisis microgenético para el estudio del desarrollo moral: consideraciones teóricas y metodológicas

Barrios, Alia, Barbato, Silviane, Branco, Angela 25 September 2017 (has links)
New ideas and methodologies need to be developed to advance our knowledge in the understanding of moral development. The intertwined nature of human activities, communication processes, and the numerous aspects of morality pose a challenge to researchers to construct a methodology that takes into account cognition, affect, sociocultural processes and characteristics, as well as the active role of individuals in their own development. In this paper we aim at suggesting fresh theoretical ideas and a micro genetic methodology to study moral development, particularly within educational contexts. / Se parte de la importancia del desarrollo de nueva ideas y metodologías que posibiliten elavance en la interpretación científica del desarrollo moral. La relación entre la ctividad humana, los procesos de comunicación y las cuestiones de moralidad, colocan a los investigadores frente al desafío de desarrollar un abordaje metodológico del desarrollo moral a partir de un enfoque que considere los aspectos cognitivos, afectivos y socioculturales, así como el papel activo de la persona en su proceso de desarrollo. A partir de esas ideas, nuestro objetivo es proponer el análisis microgenético para el estudio del desarrollo moral, tanto desde el punto de vista teórico como metodológico, en el contexto educacional.
49

IRINOTECANTOXICITY RELATED TO GILBERT´S SYNDROME   - COMPARISON OF THREE METHODS FOR GENOTYPING OF UGT1A1 (TA)n

Fredriksson, Lena January 2009 (has links)
Gilbert’s syndrome (GS) occurs in approximately 10% of the European population. The most common cause is homozygosity for UGT1A1*28, which is a TA repeat expansion in the promoter of UGT1A1. It is characterised by intermittent hyperbilirubinemia due to reduced hepatic activity of the  enzyme UDP-glucuronosyl-transferase 1A1(UGT1A1). GS also  alteres the pharmacokinetics of some drugs and increases the risk of drug toxicity. Irinotecan (Camptosar®, Campto®) is used in metastatic colorectal cancer and the active metabolite is inactivated by UGT1A1. Studies have shown that GS can be a risk factor for toxicity during irinotecan therapy. Three different methods for genotyping of UGT1A1*28 have been tested. PCR with electrophoresis used for size separation, melting temperature analysis and fluorescent PCR followed by fragment analysis on a capillary sequencer. The last method was found to be superior. This method was used for genotyping of patients with colorectal cancer treated with irinotecan and 5-fluorouracil in the Nordic VI study. A significant association between UGT1A1 genotype and plasma bilirubin level before the start of irinotecan treatment was seen (ANOVA p&lt;0.0001). Patients with GS had an overall increased risk of adverse drug reactions (Fishers Exact test p=0.02). Gilbert’s syndrome can be diagnosed by genotyping UGT1A1*28 with a fragment analysis method. Genotyping of UGT1A1*28 can be used to identify patients with an increased risk of adverse reactions to irinotecan. / Gilberts syndrom (GS) drabbar upp till 10% av befolkningen i Västeuropa. GS beror på nedsatt aktivitet av enzymet UDP-glukuronosyltransferas 1A1 (UGT1A1) i levern. Den vanligaste orsaken är att individen är homozygot för en insertion av två baser i promotorn för genen UGT1A1. Denna genvariant kallas (TA)7TAA  eller UGT1A1*28. GS leder till intermittent stegring av bilirubin vid infektioner, men bilirubinstegring kan förekomma även utan utlösande agens. GS kan också leda till bilirubinstegring vid viss läkemedelsbehandling. Irinotekan (Campto®) används vid metastaserande colorektal cancer och dess aktiva metabolit inaktiveras av UGT1A1. Det finns rapporter om att GS ger ökad risk för toxiska biverkningar av irinotekan. Tre metoder för att bestämma UGT1A1 har jämförts: PCR med elfores, PCR med smältpunktsanalys och PCR med fragmentanalys på sekvensator. Den sista metoden var bäst och användes för att genotypa UGT1A1 hos patienter med colorektal cancer från Nordic VI-studien. De behandlades med irinotekan i kombination med bolusinjektion eller infusion av 5-fluorouracil. Vi fann att  patienter med GS hade signifikant högre S-bilirubin före behandling jämfört med övriga patienter. De hade även ökad frekvens biverkningar av irinotekan (Fishers exakta test p=0,02). Genotypning av UGT1A1 kan således användas för att diagnostisera Gilberts syndrom hos patienter med oförklarad bilirubinstegring. Det kan även användas för att identifiera patienter med ökad risk för biverkningar av irinotekan.
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A genetic analysis of the eastern timber wolf

Grewal, Sonya Kaur 12 1900 (has links)
While studying packs of the eastern timber wolf in Algonquin Provincial Park in Ontario, DNA profiles at 8 microsatellite loci and the mitochondrial control region were found to be similar to those of the red wolf, C. rufus. Based on this it was suggested that both the red wolf and the eastern timber wolf have a common origin, evolving in North America, with the coyote diverging from them 150,000-300,000 years ago and with neither having any recent connection with the gray wolf that evolved in Eurasia. It was further proposed, that the eastern timber wolf retain its original species designation of C. lycaon instead of the present status of a subspecies of the gray wolf. Four "types" or "races" of wolves have been previously described in Ontario. Using DNA profiles, assignment tests identified four groups, which were typified by animals in Algonquin Provincial Park, Pukaskwa National Park, Frontenac Axis and those north of Lake Superior. The tests indicate that Frontenac animals are hybrids between the western coyote and C. lycaon and represent the eastern coyote. Pukaskwa maintains a small wolf population, which is genetically closer to the gray wolves of the Northwest Territories than the surrounding C. lycaon. These may represent an isolated remnant population of the original "Ontario type" (C. lupus). Animals north of Lake Superior were identified as C. lycaon, but represent products of hybridization between C. lycaon and C. lupus. Currently within Ontario, Algonquin Park contains the largest protected area of the eastern timber wolf. DNA profiles, including Y-linked microsatellite loci were used to establish maternity, paternity and kin relationships for 102 animals from 24 packs over a 12-year period. A complex pack structure was identified. A pack is not composed simply of an unrelated breeding pair and their offspring and subordinates appear to enter pack systems through adoption, pack splitting, dispersal and immigration. Relatively high genetic structuring was found between the Park animals and the "Tweed" wolves to the southeast suggesting introgression of coyote genetic material is not a present concern to the integrity of park animals. Evidence of gene flow with animals to the west, northeast and northwest coupled with the high genetic diversity, suggest that the Park animals are not an island population, but the southern part of a larger metapopulation of C. lycaon. Increased interest in the relationship of the red and eastern wolves led to the investigation of a gene in the major histocompatibility complex. Allelic variation in the exon 2 region of the DLA-DQA1 locus was analysed for gray wolves, red wolves, the eastern timber wolf and the western coyote. Twelve alleles were identified, seven of which were previously characterized in dogs. Non-synonomous nucleotide substitutions was 3.0 times higher than the synonomous changes, indicative of strong positive selection. These data provide baselines for the determination of allele frequencies and their distribution across the geographical range of the four species in North America. The results in this thesis have sparked numerous debates with respect to the protection of the wolves in Algonquin Provincial Park and reintroduction of wolves into Northeastern United States. The data support the idea that the C. lycaon population in Ontario is relatively large, numbering in the thousands rather than the hundreds. Concern for the conservation of wolves in Ontario should be directed at the declining numbers of gray wolves present in Ontario. / Thesis / Master of Science (MSc)

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