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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.
1

Ternerio sindromas: kariotipo, fenotipo ir šeiminio daugiaveiksnio paveldėjimo tyrimas / Turner syndrome: investigation of karyotype, phenotype and familial multifactorial inheritance

Šalomskienė, Loreta 02 September 2008 (has links)
Darbo tikslas buvo nustatyti Ternerio sindromo fenotipo ryšį su nustatyta chromosomine konstitucija ir jo įtaką šeiminei homeostazei. TS paplitimas, dažnis ir ligonių amžius diagnozavimo metu iki šiol nebuvo aprašytas mūsų tirtoje populiacijoje. KMU biologijos katedros citogenetikos laboratorijoje buvo ištirti kariotipai 1271 asmeniui, kuriam galima buvo įtarti TS: naujagimiai su įgimtomis sklaidos ydomis; mergaitės su fizinio vystymosi atsilikimais; mergaitės su brendimo atsilikimu; moterys su pirmine amenorėja; moterys su antrine amenorėja; moterys, tirtos dėl persileidimų ir nevaisingumo. Kariotipo pakitimai, būdingi TS, diagnozuoti 236 asmenims (18,6 proc.). Išskirti trys pagrindiniai kariotipo pakitimų variantai ir įvertinta, ar vienoda jų įtaka fenotipui. Tirta, ar yra skirtumas šių ligonių grupių fenotipe pagal tirtuosius parametrus: nėštumo trukmę, naujagimių kūno ilgį ir svorį, mergaičių ūgį ir svorį iki 18 metų amžiaus, tėvų amžių gimstant vaikui, sibsų amžių, paciento, kuriam įtariamas TS, amžių kariotipo tyrimo metu. Ištirta ir aprašyta keletas retų chromosomų disbalanso variantų. Nustatyta, kad monosominiai ligoniai dažniau vienintelę X chromosomą paveldi iš motinos (80,5 proc.), negu iš tėvo. Pirmą kartą atliktas šeiminis daugiaveiksniškai paveldimų požymių tyrimas (elektrokardiogramos ir gliukozės toleravimo mėginys) ne tik probandams, sergantiems TS, bet ir jų pirmosios eilės giminėms. Lietuvoje bent pusė TS atvejų lieka neatpažinti, todėl, siekiant kuo... [toliau žr. visą tekstą] / The aim of this study is to evaluate the link of chromosome constitution in Turner syndrome and in disruption of familial homeostasis. The distribution and incidence of TS in population nor the age of patients at the moment of diagnosis were not described previously. Cytogenetical laboratory at the Department of biology has investigated karyotypes for 1271. The number of abnormal karyotypes found is 236 (18.6%). We divided the patients into three groups according to logical, in our opinion, changes in their karyotypes. The aim of our research was to find out, if there were significant differences in phenotypes within those groups. Such traits were chosen for the comparison: the duration of pregnancy, length and weight of newborns, height and weight of the girls under 18 years old, the age of parents at birth of propositus, the age of the siblings, and the age at which TS was diagnosed for the patient. We predicted, that in a case of complete 45,X monosomy the clinical manifestation of the syndrome should be more severe, and this group of patients would differ from other karyological groups. We have found that in 80.5% of cases X chromosome had the maternal origin and in the rest 19.5% – paternal. To investigate the multifactorially inherited traits (electrocardiograms and glucose tolerance test) in relatives of Turner syndrome patients. We suggest that for the earlier diagnosis of TS, it is reasonable to investigate all girls, whose height is less than 3rd percentile.
2

Chromosominių aberacijų įtaka galvijų reprodukcinėms savybėms / The influence of chromosomal aberrations on reproductive features of cattle

Žaliagirytė, Gintarė 18 June 2013 (has links)
Darbo uždaviniai: surinkti ir išanalizuoti mokslinę literatūrą apie chromosominius pakitimus ir jų poveikį galvijų reprodukcijai. Paruošti ir ištirti galvijų chromosomų preparatus. Įvertinti chromosomų skaičiaus ir struktūros pakitimus bei jų įtaką reprodukcinėms savybėms. Rezultatai ir aptarimas: ištyrus karves, kurioms nustatyti reprodukcijos sutrikimai, buvo identifikuoti ir chromosomų struktūros, ir chromosomų skaičiaus pakitimai. Didžiąją dalį chromosomų struktūros pakitimų, t. y. 38,2 proc., sudarė spragos vienoje chromatidėje (S1), 16,9 proc. spragos abiejose chromatidėse (S2) ir 16,9 proc. – chromatidžių trūkiai (D1). Fragmentai (F) sudarė 12,4 proc. Mažiausią dalį chromosomų struktūros aberacijų, t. y. 2,2 proc., sudarė žiedinės chromosomos (Ž) ir 2,2 proc. – chromosomų trūkiai (D2). Iš chromosomų skaičiaus pakitimų rasta 7,9 proc. poliploidijų (P). Ištyrus karves, kurioms nenustatyti reprodukcijos sutrikimai, taip pat buvo identifikuoti tiek chromosomų struktūros, tiek skaičiaus pakitimai. Iš chromosomų struktūros pakitimų nustatyta: 28,6 proc. spragų vienoje chromatidėje (S1), 11,4 proc. chromatidžių trūkių (D1), 11,4 proc. fragmentų (F), 8,6 proc. spragų abiejose chromatidėse (S2). Žiedinių chromosomų ir dicenrikų nenustatyta. Iš chromosomų skaičiaus pakitimų aptikta 34,3 proc. poliploidijų (P) ir 2,9 proc. trisomijų (Tr). Karvių grupėje, turinčių reprodukcijos sutrikimų, ląstelių su pakitimais pasitaiko 3,3 karto dažniau (p<0,001) nei kontrolinėje grupėje... [toliau žr. visą tekstą] / The Object of the work: cytogenetic analysis was performed on 26 cows from animal farm in Giraitė, 12 cows with reproductive disorder and 14 cows with no reproductive disorder (the control group). The research was performed by standard citogenetical approach modified in laboratory. The extent of the work: 48 pages. There are 4 tables and 10 pictures included. The aim of the work: to evaluate the influence of chromosomal aberrations on reproductive features of the cattle. The tasks of the work: to collect and analyze scientific literature on chromosomal changes and their impact on reproduction of cattle. To prepare and investigate the preparation of cattle chromosomes, estimate the structural and numeral variations of chromosomes and their influence on reproductive characteristics. The results and their discussion: after the examination of the cows with reproductive disorders the structural and numeral variations of chromosomes were identified. The major part of structural variations in chromosomes, i.e. 38.2%, consisted of gaps in one chromatid (S1), 16.9% of gaps in both chromatids (S2), 16.9% of cracks in chromatids (D1) and 12.4% of fragments (F). The least part (2.2%) of structural aberrations of chromosomes consisted of circular chromosomes (Ž) and 2.2% of cracks in chromosomes (D2). There were 7.9% of poliploidies (P) found in numeral variations of chromosomes. There were also identified both the structural and numerical variations of chromosomes after examining the... [to full text]
3

Karvių genomo nestabilumo ryšys su pieno produktyvumu / Cow genome instability in connection with milk productivity

Antanavičienė, Jūratė 19 May 2014 (has links)
Darbo tikslas: ištirti karvių genomo nestabilumo ryšį su pieno produktyvumu. Darbo uždaviniai: 1. Surinkti ir išanalizuoti mokslinę literatūrą apie galvijų chromosomų skaičiaus ir struktūros pakitimus bei jų ryšį su produktyvumo savybėmis. 2. Paruošti karvių chromosomų preparatus. 3. Ištirti chromosomų skaičiaus ir struktūros pakitimus aukšto ir žemo produktyvumo pieninėms karvėms. 4. Apskaičiuoti chromosomų skaičiaus ir struktūros pakitimų dažnį ir spektrą aukšto ir žemo produktyvumo pieninėms karvėms. 5. Nustatyti ryšį tarp chromosomų skaičiaus ir struktūros pakitimų ir pieno produkcijos kiekio. Darbo metodai: mokslinės literatūros, straipsnių, statistinių duomenų analizė. Praktinėje dalyje atlikti karvių chromosomų tyrimai. Rezultatai aptarti juos apibendrinus. Darbe remtasi įvairiais užsienio ir lietuvių moksliniais darbais, straipsniais, tyrimų medžiaga, darbe analizuojama tema. Darbo objektas: citogenetinė analizė atlikta 20 karvių iš LSMU VA praktinio mokymo ir bandymų centro, 10 aukšto produktyvumo karvių ir 10 žemo produktyvumo karvių. Tyrimai atlikti standartiniu citogenetiniu metodu. Rezultatai ir aptarimas: žemo produktyvumo karvės turėjo žymiai daugiau chromosominių pakitimų. Daugiausiai chromosomų struktūros pakitimų, t.y. 37,5 proc., sudaro spragos vienoje chromatidėje (S1), 15,6 proc. – spragos abiejose chromatidėse (S2), 17,2 proc. – chromatidžių trūkiai (D1), 9,4 proc. – fragmentai (F). Mažiausią dalį chromosomų struktūros pakitimų, t. y. 3,1 proc. sudaro... [toliau žr. visą tekstą] / The Object of the work: cytogenetic analysis was performed on 20 cows from LSMU VA practice and research centre, 10 productive cows and 10 unproductive cows. The research was performed by standard citogenetical laboratory. The aim of the work: to evaluate the influence of chromosomal aberrations on cow high productivity. The tasks of the work: collect and analyze scientific literature on bovine chromosome number and structure of the environment and their relationship with performance traits. Prepared bovine chromosome preparations. To investigate the chromosome number and structure changes in high and low productivity of dairy cows. Calculate the number of chromosomes and structural changes in the frequency and range of high and low productivity of dairy cows. Determine the relationship between chromosome number and structure changes and milk production levels. The results and their discussion: after the examination of the unproductive cows the structural and numeral variations of chromosomes were identified. Most part of structural variations in chromosomes, i.e. 37,5 proc., consisted of gaps in one chromatid (S1), 15,6 proc.of gaps in both chromatids (S2), 17,2 proc. of cracks in chromatids (D1) .There were 10,9 proc. of poliploidies (P) found in numeral variations of chromosomes. There were also identified both the structural and numerical variations of chromosomes after examining the productive cows. These structural variations of chromosomes were identified: 34,6 proc... [to full text]
4

Genotoxicidade do cádmio em tomateiro (Solanum lycopersicum L.) / Cadmium genotoxicity in tomato (Solanum lycopersicum L.)

Pizzaia, Daniel 10 April 2013 (has links)
O cádmio (Cd) é um metal pesado encontrado naturalmente no meio ambiente em níveis da ordem de 0,5 mg.L-1. No entanto, atividades humanas têm aumentado sua concentração na biosfera, por meio de efluentes industriais não tratados. Essa elevação pode causar estresse oxidativo nas plantas, conferindo aberrações cromossômicas, danos ao DNA e alterações nos microtúbulos das células. Pesquisas têm avaliado os efeitos do Cd em diversas espécies de plantas. Entretanto, o tomateiro ainda não tem sido alvo de tais pesquisas mesmo sendo considerada uma planta modelo em outras áreas. Dessa forma, justifica-se a condução de experimentos que avaliem a genotoxicidade do Cd nesta espécie através de abordagens baseadas na citogenética. Este estudo foi conduzido para avaliar efeitos genotóxicos do Cd em células meristemáticas de raízes de tomateiro do cultivar Micro-Tom através da investigação de aberrações cromossômicas, grau de danos causados ao DNA e anormalidades das fibras do fuso mitótico e do citoesqueleto. Evidenciou-se que a partir da dose mínima de Cd empregada (variou de 0,018 a 13 mg.L-1), foram observadas aberrações cromossômicas, tais como quebras, perdas, adesões e pontes. Ainda empregando-se as mesmas doses de Cd, constataram-se danos ao DNA por meio do ensaio de cometa. Porém, de acordo com a dose de 3,7 mg.L-1 de Cd, os microtúbulos de ?-tubulinas sofreram modificações em sua estrutura que alteram a organização do citoesqueleto celular, do fuso mitótico e da citocinese. Em geral, o tomateiro apresentou sensibilidade em baixas concentrações de Cd, o que possibilita considerá-lo como uma importante planta modelo com potencial para estudos de genotoxicidade aplicados ao monitoramento ambiental e testes de compostos tóxicos. / Cadmium (Cd) is a heavy metal found naturally in the environment at low levels (around 0.5 mg.L-1). Some human activities have increased its concentration in the biosphere due to untreated industrial effluents. This increase may induce oxidative stress in plants and potentially causing chromosomal aberrations, DNA damage and changes in the cell microtubules. Researchers have evaluated the Cd effects in several plant species. However, tomato has not been the target of these researches even though it is considered as a plant model in others areas. Therefore, experiments are needed to assess the genotoxicity of Cd in this plant species through cytogenetical approaches. The present work was carried out to assess the Cd genotoxic effects on root-meristem cells of Micro-Tom based on chromosomal aberrations, DNA damage and abnormal mitotic spindle fibers and cytoskeleton. Low Cd concentrations (ranging from 0.018 to 13 mg.L-1) were able to induce chromosomal aberrations such as breaks, losses, stickiness and bridges. At the same concentrations, DNA damage was evidenced using the comet assay. Concentrations of 3.7 mg.L-1 Cd induced structural modifications of the microtubules of ?-tubulin that altered the organization of the cytoskeleton, the mitotic spindle fibers and cytokinesis. In general, tomato presented sensitivity to low concentrations of Cd. These results suggest that tomato is also a good model for studies of genotoxicity to be applied on environmental monitoring and toxic compounds assays.
5

Genotoxicidade do cádmio em tomateiro (Solanum lycopersicum L.) / Cadmium genotoxicity in tomato (Solanum lycopersicum L.)

Daniel Pizzaia 10 April 2013 (has links)
O cádmio (Cd) é um metal pesado encontrado naturalmente no meio ambiente em níveis da ordem de 0,5 mg.L-1. No entanto, atividades humanas têm aumentado sua concentração na biosfera, por meio de efluentes industriais não tratados. Essa elevação pode causar estresse oxidativo nas plantas, conferindo aberrações cromossômicas, danos ao DNA e alterações nos microtúbulos das células. Pesquisas têm avaliado os efeitos do Cd em diversas espécies de plantas. Entretanto, o tomateiro ainda não tem sido alvo de tais pesquisas mesmo sendo considerada uma planta modelo em outras áreas. Dessa forma, justifica-se a condução de experimentos que avaliem a genotoxicidade do Cd nesta espécie através de abordagens baseadas na citogenética. Este estudo foi conduzido para avaliar efeitos genotóxicos do Cd em células meristemáticas de raízes de tomateiro do cultivar Micro-Tom através da investigação de aberrações cromossômicas, grau de danos causados ao DNA e anormalidades das fibras do fuso mitótico e do citoesqueleto. Evidenciou-se que a partir da dose mínima de Cd empregada (variou de 0,018 a 13 mg.L-1), foram observadas aberrações cromossômicas, tais como quebras, perdas, adesões e pontes. Ainda empregando-se as mesmas doses de Cd, constataram-se danos ao DNA por meio do ensaio de cometa. Porém, de acordo com a dose de 3,7 mg.L-1 de Cd, os microtúbulos de ?-tubulinas sofreram modificações em sua estrutura que alteram a organização do citoesqueleto celular, do fuso mitótico e da citocinese. Em geral, o tomateiro apresentou sensibilidade em baixas concentrações de Cd, o que possibilita considerá-lo como uma importante planta modelo com potencial para estudos de genotoxicidade aplicados ao monitoramento ambiental e testes de compostos tóxicos. / Cadmium (Cd) is a heavy metal found naturally in the environment at low levels (around 0.5 mg.L-1). Some human activities have increased its concentration in the biosphere due to untreated industrial effluents. This increase may induce oxidative stress in plants and potentially causing chromosomal aberrations, DNA damage and changes in the cell microtubules. Researchers have evaluated the Cd effects in several plant species. However, tomato has not been the target of these researches even though it is considered as a plant model in others areas. Therefore, experiments are needed to assess the genotoxicity of Cd in this plant species through cytogenetical approaches. The present work was carried out to assess the Cd genotoxic effects on root-meristem cells of Micro-Tom based on chromosomal aberrations, DNA damage and abnormal mitotic spindle fibers and cytoskeleton. Low Cd concentrations (ranging from 0.018 to 13 mg.L-1) were able to induce chromosomal aberrations such as breaks, losses, stickiness and bridges. At the same concentrations, DNA damage was evidenced using the comet assay. Concentrations of 3.7 mg.L-1 Cd induced structural modifications of the microtubules of ?-tubulin that altered the organization of the cytoskeleton, the mitotic spindle fibers and cytokinesis. In general, tomato presented sensitivity to low concentrations of Cd. These results suggest that tomato is also a good model for studies of genotoxicity to be applied on environmental monitoring and toxic compounds assays.

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