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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.
21

Oral and Intravenous Itraconazole for Systemic Fungal Infections in Neutropenic Haematological Patients: Meeting Report

Prentice, H. Grant, Caillot, Denis, Dupont, B., Menichetti, F., Schuler, Ulrich 18 March 2014 (has links) (PDF)
Effective prevention, or treatment, of invasive fungal infection in the neutropenic patient has hitherto been unsatisfactory because of either an inadequate anti-fungal spectrum of the agent or important toxicity. Itraconazole is effective against a broad spectrum of the opportunistic pathogens seen in Europe and North America. Prior problems with absorption, e.g. in the marrow transplant recipient, have been overcome with the introduction of an oral solution and an i.v. preparation. The deliberations of an expert meeting held in June, 1998 include recommendations on which patient requires one of these new preparations based on clinical trials, the dose and route. Important drug interactions are also detailed. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
22

Vliv huminové látky HS 1500 na toleranci jesetera malého vůči dusitanům / Influence of humic substance HS 1500 on tolerance of Sterlet to nitrite

BULÍČEK, Vojtěch January 2014 (has links)
The aim of the thesis was to assess the effect of humic substance HS 1500 on the tolerance of Sterlet (Acipenser ruthenus) to nitrite. Preparation Huminfeed was used as a source of substance HS 1500. Tolerance of Sterlet to nitrite was assessed on the basis of the results of acute toxicity tests and the results of haematological and biochemical blood examination of fish that were exposed to increased concentrations of nitrite in the presence and absence of preparation Huminfeed.
23

Estudo sobre a participa??o de roedores na cadeia de transmiss?o de Leishmania infantum (Protozoa: Trypanosomatidae) no Rio Grande do Norte

Barbosa, Patr?cia Batista Barra Medeiros 11 July 2005 (has links)
Made available in DSpace on 2014-12-17T14:03:26Z (GMT). No. of bitstreams: 1 PatriciaBBMB.pdf: 749567 bytes, checksum: e355ba98f4fd47889fd16327a3ca1f09 (MD5) Previous issue date: 2005-07-11 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / American visceral leishmaniasis is a zoonosis caused by Leishmania infantum and transmitted by the bite of the sand flies Lutzomia longipalpis.The main domestic reservoir is the dog, while foxes and opposums are the known wild reservoirs. However, identification of natural infections with L. infantum in rodents appears for need of investigating the participation of these rodents how source of infection of the parasite. In the present work the Leishmania infantum infection was investigated in rodents captured in Rio Grande do Norte, aiming at to offer subsidies to the understanding of the epidemic chains of LVA in the State. Thirteen Galea spixii were distributed in four groups, being G1 the group control with four animals and the others, G2, G3 and G4, with three animals each. Those animals were intraperitoneally inoculated with 107 promastigotas of L. infantum and accompanied for, respectively, 30, 90 and 180 days. Weekly the animals were monitored as for the corporal weight and rectal temperature. At the end of each stipulated period the animals were killed. Blood were used for determination of the parameters biochemical and haematological, PCR, ELISA, microscopic examination and cultivation in NNN medium. Liver, spleen and lymph node were used in Giemsa-stained impression and cultivation in NNN medium. Liver and spleen fragments were still used in PCR and histopathological, respectively. At the same time 79 rodents of the species Rattus rattus, Bolomys lasiurus, Oligoryzomys nigripis, Oryzomys subflavus and Trichomys apereoides were captured in the Municipal districts of Brejinho, Campo Grande, Coronel Ezequiel, Passa e Fica and V?zea for identification of natural infection with L. infantum. Evidence of infection was checked by direct examination of Giemsa-stained impression of liver, spleen and blood and culture of these tissues in NNN medium. Antibodies were researched by ELISA. They were not found differences among the weigh corporal final, rectal temperature and biochemical and haematological parameters of the Galea spixii controls and infected. The rectal temperature of the animals varied from 36OC to 40OC. For the first time values of the haematocrit (33,6% to 42,8%), hemoglobin (10,2 to 14,5g/dl), erythrocyts number (4,67x106 to 6,90x106/mm3), total leukocytes (0,9x103 to 9,2x103/mm3), platelets (49x103 to 509x103/mm3) total proteins (1,56 to 6,06 g/dl), albumin (1,34 to 3,05 g/dl) and globulins (0,20 to 3,01 g/dl) of the Galea spixii were determined. The lymphocytes were the most abundant leucocytes. Infection for L. infantum was diagnosed in two animals euthanasied 180 days after the infection. In one of the animals was also identified antibodies anti-Leishmania. The parasite was not found in none of the five other species of rodents captured. Galea spixii are resistant to the infection for L. infantum and they are not good models for the study for visceral leishmaniose, although they can act as infection sources. More studies are necessary to determine the paper of the rodents in the epidemic chain of transmission of the visceral leishmaniose in the State of Rio Grande do Norte / A leishmaniose visceral americana ? uma zoonose causada pelo parasita Leishmania infantum e transmitida pela picada do fleb?tomo Lutzomya longipalpis. O c?o ? o principal reservat?rio dom?stico, enquanto que raposas e gamb?s s?o os reservat?rios silvestres conhecidos. No entanto, a identifica??o de infec??es naturais com L. infantum em roedores aponta para a necessidade de se investigar a participa??o destes animais como fonte de infec??o do parasita para os insetos vetores. No presente trabalho investigou-se a infec??o com parasita Leishmania infantum em roedores capturados no Rio Grande do Norte, objetivando oferecer subs?dios ? compreens?o das cadeias epidemiol?gicas da LVA no Estado. Treze pre?s da esp?cie Galea spixii foram distribu?dos em quatro grupos, sendo G1 o grupo controle com quatro animais e os demais, G2, G3 e G4, com tr?s animais cada. Esses animais foram inoculados por via intraperitonial com 107 promastigotas de L. infantum e acompanhados por, respectivamente, 30, 90 e 180 dias. Semanalmente os animais foram monitorados quanto ao peso corporal e temperatura retal. Ao final de cada per?odo estipulado os animais foram eutanasiados. O sangue colhido foi utilizado na determina??o dos par?metros bioqu?micos e hematol?gicos, PCR, ELISA, confec??o de esfrega?o sangu?neo e cultivo em meio NNN. Fragmentos de f?gado, ba?o e linfonodos foram utilizados para confec??o de l?minas por aposi??o e cultivo em meio NNN. Fragmentos de f?gado e ba?o foram ainda utilizados para realiza??o de PCR e histopatol?gico, respectivamente. Concomitantemente 79 roedores das esp?cies Rattus rattus,Bolomys lasiurus, Oligoryzomys nigripis, Oryzomys subflavus e Trichomys apereoides foram capturados nos Munic?pios de Brejinho, Campo Grande, Coronel Ezequiel, Passa e Fica e V?rzea para identifica??o de infec??o natural por L. infantum. O diagn?stico da infec??o nos animais foi realizado pelo exame direto das impress?es coradas com Giemsa e cultura em meio NNN de f?gado, ba?o e sangue. N?o foram encontradas diferen?as no o ganho de peso total, temperatura retal e par?metros bioqu?micos e hematol?gicos dos pre?s controles e infectados. A temperatura retal variou entre 36OC e 40OC. Pela primeira vez foram determinados os valores do hemat?crito (33,6% a 42,8%), hemoglobina (10,2 a 14,5g/dl), n?mero de eritr?citos (4,67x106 a 6,90x106/mm3), leuc?citos totais (0,9x103 a 9,2x103/mm3), plaquetas (49x103 a 509x103/mm3), prote?nas totais (1,56 a 6,06 g/dl), albumina (1,34 a 3,05 g/dl) e globulinas (0,20 a 3,01 g/dl) nesta esp?cie. Os linf?citos foram os leuc?citos mais abundantes. Infec??o por L. infantum foi diagnosticada em dois animais eutanasiados aos 180 dias, sendo que em um desses tamb?m foram identificados anticorpos contra o parasita. N?o foi observada positividade em nenhuma das cinco outras esp?cies de roedores capturadas. A esp?cie Galea spixii ? resistente ? infec??o por L. infantum e, portanto, n?o ? bom modelo para o estudo da leishmaniose visceral, embora possam atuar como fontes de infec??o. Mais estudos s?o necess?rios para que se possa determinar o papel dos roedores na cadeia epidemiol?gica da leishmaniose visceral no Estado do Rio Grande do Norte
24

Eritrograma e leucograma como ferramenta para avaliar animais de produção: influência do período gestacional e puerpério, alimentação e raça. / Erythrogram and leukogram as a tool to evaluate animals of production: influence of the gestational and puerperium, feeding and race.

ANDRADE, Évyla Layssa Gonçalves. 09 May 2018 (has links)
Submitted by Rebeka Godeiro (rebeka_carvalho@hotmail.com) on 2018-05-09T12:11:53Z No. of bitstreams: 1 ÉVILA LAYSSA GONÇALVES ANDRADE - DISSERTAÇÃO ZOOTECNIA 2018.pdf: 781555 bytes, checksum: 737e0c348795cf611733127cadba1da6 (MD5) / Made available in DSpace on 2018-05-09T12:11:53Z (GMT). No. of bitstreams: 1 ÉVILA LAYSSA GONÇALVES ANDRADE - DISSERTAÇÃO ZOOTECNIA 2018.pdf: 781555 bytes, checksum: 737e0c348795cf611733127cadba1da6 (MD5) Previous issue date: 2018-02-26 / Capes / Objetivou-se avaliar a influência da gestação e do puerpério, alimentação e raça sobre o hemograma de ovelhas deslanadas. Utilizou-se 40 ovelhas, sendo 20 da raça Santa Inês e 20 da raça Morada Nova, distribuídos em delineamento inteiramente casualizado em arranjo de parcelas subdivididas no tempo. Durante o período experimental, os animais permaneceram em piquetes de pastagem Andropogon gayanus, sendo recolhidos ao final da tarde para receberem suplementação. As amostras de sangue foram colhidas a cada quatorze dias, sempre pela manhã, antes dos animais serem liberados para o pasto, por punção da veia jugular, para a realização do hemograma. Não se observou influência do nível de suplementação no eritrograma dos animais (P < 0,05). No leucograma, a suplementação influenciou apenas a contagem de neutrófilos (P < 0,05). A raça Morada Nova apresentou maiores concentrações de hemoglobina e de hematócrito e contagem total de leucócitos que a raça Santa Inês. Relativo à influência da gestação e do puerpério sobre o eritrograma, observou-se que nesse período ocorreu um reestabelecimento dos valores da crase sanguínea, incluindo proteínas plasmáticas totais, que elevaram durante este período como forma de compensação ao feto e a alta exigência nutricional, permanecendo até o final do puerpério quando os cordeiros foram desmamados. Os fatos anteriormente discutidos evidenciam que não houve influência do período de gestação e puerpério sobre o eritrograma dos animais em estudo, porém a suplementação e a raça se mostram influentes no quadro leucocitário desses animais. / The objective of this study was to evaluate the influence of gestation and puerperium, feeding and breed on the hemogram of sheep. We used 40 sheep, 20 of Santa Ines and 20 Morada Nova, distributed in a completely randomized design in a split plot arrangement in time. During the experimental period, the animals were kept in pickets of Andropogon gayanus pasture being collected in the late afternoon to be supplemented. Blood samples were taken every fourteen days, always in the morning, before the animals were released into the pasture, by jugular vein puncture for blood count. There was no influence on the level of supplementation in the erythrogram (P <0.05). In leucogram, the concentrate supply influenced only neutrophiles (P <0.05). The Morada Nova breed had higher hemoglobin and hematocrite and total leukocyte count than the Santa Ines breed. On the influence of pregnancy and puerperium in the erythrocyte, it is observed that during this period there is a reestablishment of the values of blood crasis, including total plasma proteins that increase during this period as compensation to the fetus and high nutritional requirements, remaining until the end of the puerperium when the lambs were weaned. The facts discussed above show that there was no influence of the gestation and puerperium period on the erythrogram of the animals under study, however, supplementation and breed are influential in the leukocyte status of these animals.
25

Změny hematologických ukazatelů u ryb v souvislosti se zvýšenými koncentracemi dusitanů ve vodě. / Changes of haematological parameters in fish after nitrite exposure

GŘUNDĚL, Miroslav January 2008 (has links)
The aim of this thesis was to examine the influence of nitrite on fish. Influence of nitrite was evaluated on the basis of acute and sub-chronic toxicity tests results on rainbow trout (Oncorhynchus mykiss). The effects of nitrite were also observed in wels catfish {--} albino (Silurus glanis). On the basis of the results of acute toxicity tests, values of lethal concentration of nitrite for rainbow trout (Oncorhynchus mykiss) (96hLC50 = 11.2 mg.l-1 NO2-) and for wels catfish {--} albino (Silurus glanis) (96hLC50 = 15.8 mg.l-1 NO2-) were calculated. Using results of acute toxicity test for rainbow trout (Oncorhynchus mykiss) and with respect to legislative requirements, concentrations of nitrite for sub-chronic toxicity test were selected. The results of sub-chronic toxicity test showed that nitrite concentration of 3 mg.l-1 NO2- during 28-day exposition caused 65 % fish mortality. This concentration also caused growth rate decrease compared to control. Growth rate among fish exposed to concentrations lower then 3 mg.l-1 NO2- was comparable to control. Among fish exposed to nitrite concentration of 0.6 mg.l-1 NO2- and higher nitrite accumulation in muscle and in blood plasma was observed. Haematological examination showed statistically significant decrease of haematocrit value and concentration of haemoglobin and increase of the number of leukocytes in experimental fish. Other measured haematological parameters (Ery, MCV, MCH and MCHC) were comparable with control.
26

IL-6 tronquée, un antagoniste naturel de l’IL-6 ? : sélection d’un système d’expression : établissement de preuves de concept in vitro : dans les hémopathies malignes et dans les adénocarcinomes du rein / Truncated IL-6 , a natural IL-6 antagonist ? : selection of an expression system and establishment of in vitro proof of concept on haematological malignancies and on renal adenocarcinoma cells

Mansuy, Adeline 17 December 2009 (has links)
L'interleukine-6 (IL-6) exerce des propriétés biologiques multiples telles que l'activation des cellules immunocompétentes, l'activation de la réponse inflammatoire et l'hématopoïèse. Produite également par les cellules tumorales, l'IL-6 impacte la prolifération, la différenciation et la survie de ces dernières. L'IL-6 représente donc depuis plusieurs années une cible thérapeutique pertinente. Dans la première partie de ce travail, nous avons exploré une nouvelle piste potentielle pour bloquer l'activité biologique de l'IL-6, en utilisant un antagoniste naturel que notre équipe a identifié dans plusieurs lignées d'adénocarcinomes du rein, à savoir la molécule tronquée tIL-6. Suite à l'évaluation comparée de deux systèmes d'expression (E. coli versus CHO), nous avons retenu les cellules CHO comme source de production de fractions enrichies en tIL-6 par chromatographie de gel d'exclusion. Disposant d'un panel d'adénocarcinomes de rein (ACHN, Caki1, CLB CHA, CLB VER) et d'une lignée érythroleucémique (TF1), l'activité fonctionnelle de tIL-6 in vitro a été étudiée sur (1) la signalisation IL-6 induite, (2) la prolifération cellulaire IL-6 induite, la survie cellulaire et (4) la modulation de l'expression de protéines relevantes de l'apoptose. La molécule tIL-6 bloque la phosphorylation de la tyrosine Tyr705 de STAT3, qui est un des éléments clés de la voie de signalisation de l'IL-6. Nous rapportons également une autre observation nouvelle indiquant que tIL-6 exerce un effet pro-apoptotique sur certaines lignées RCC. Dans la seconde partie de notre étude, l'impact d'un Ac Mo anti IL-6 dans la réversion de la résistance aux cytotoxiques ou à la radiothérapie a été étudié. Nos résultats démontrent que la voie IL-6 ne constituerait pas un mécanisme majeur de résistance / Interleukin-6 (IL-6) plays numerous physiological roles including haematopoiesis, immune response and inflammation, but also plays a role in modulating cell growth, differentiation and survival of tumors cells. The first goal of the present study was to investigate on the potential role of the truncated protein IL-6 (tIL-6) encoded by the spliced IL-6 mRNA discovered in renal carcinoma cells (RCC). The R&D program was designed based on an industrial approach, aiming at reaching the decision stage to enter or not into preclinical development. Firstly two different expression systems were investigated (E. coli versus CHO cell line). The mammalian expression system was selected as the protein source since a recombinant glycosylated tIL-6 with a molecular weight similar to the predicted natural molecule was obtained from enriched fractions following size exclusion chromatography. Secondly by using a cell line panel including renal carcinoma cells (ACHN, Caki-1, CLB CHA, CLB-VER ) and an erythroleucemic cell line (TF1), in vitro tIL-6 functional activity were analyzed on (1) IL-6 induced signaling, (2) IL-6 induced cell proliferation, (3) on cell survival and also (4) on expression of specific set of proteins involved in apoptosis pathways. The truncated IL-6 was found inhibit IL-6 induced STAT3 Tyr705 and to induce apoptosis in some RCC cell lines which could be depending on IL-6 expression. Understanding more precisely the role of natural truncated IL-6 and its impact in cell tumour growth control will be a major issue in the development of innovative approach to antagonize directly or not IL6. The second goal of the present study was to investigate on reversing resistance of cancer cell lines to cytotoxics or ionizing radiations through the use of a monoclonal antibody directed against IL-6. Our data support the fact that IL-6 is not the preponderant actor of cell resistance to cytotoxics and ionizing radiations, which seems to be regulated by a complex network of proteins
27

Systemische Wirkungen und Nebenwirkungen einer dermal verabreichten dexamethasonhaltigen Formulierung bei klinisch gesunden Pferden

Allersmeier, Maren 20 June 2011 (has links) (PDF)
Da topische Glucocorticoide im Vergleich zur parenteralen Anwendung weniger systemische (Neben)Wirkungen haben können, werden sie bevorzugt in der Human- und Veterinärmedizin eingesetzt. Jedoch konnte bei vielen Untersuchungen gezeigt werden, dass topische Glucocorticoide je nach Applikationsdauer, -ort, Wirkstoffpotenz, -dosis und Behandlungsfläche ausgeprägte messbare Reaktionen wie Suppression der HHNA und der Immunzellen hervorrufen können. Beim Pferd wurden jedoch dahingehend bisher keine Untersuchungen durchgeführt. Da Glucocorticoide im Pferdesport auch dopingrelevant sind wurde der Frage nachgegangen, ob nach der dermalen Applikation eines niederpotenten Glucocorticoidpräparates auf die Haut gesunder Pferde systemische Effekte auftreten können und ob ein, nach perkutaner Resorption auftretender, Wirkstoffspiegel im Blut gemessen werden kann. Im Rahmen dieser Dissertation standen 10 erwachsene, klinisch gesunde Versuchspferde zur Verfügung. Die Versuchsdurchführung erfolgte in 3 Phasen. Vor Behandlungsbeginn (Tag 0) wurden von jedem Pferd die Kontrolldaten erfasst. Die Applikation der Dexamethasonformulierung erfolgte über einen Zeitraum von 10 Tagen. 2 mal täglich wurden 50 g einer 0,017 %igen Dexamethasonemulsion auf eine definierte Hautfläche (30 x 50 cm) aufgetragen. Die Blutentnahmen zur Gewinnung der Proben erfolgten am 2., 6., 8., und 10. Tag der Behandlung. Die Nachbehandlungsphase erstreckte sich über einen Zeitraum von 20 Tagen ohne die Dexamethasonanwendung. Hier erfolgte die Probengewinnung an den Tagen 3, 7, 11, 14 und 20 nach Absetzen der Behandlung. Aus den gewonnenen Plasmaproben wurden die Konzentrationen von Cortisol, Insulin, T3 und T4 mittels Radioimmunoassay bestimmt, sowie die ACTH-Konzentrationen mittels Chemilumineszenz-Enzymimmunometrischem Assay. Darüber hinaus wurden die hämatologischen und blutchemischen Parameter gemessen. Die Funktion des negativen Feetback-Mechanismus der Hypothalamus-Hypophysen-Nebennierenrinden-Achse wurde mittels eines ACTH-Stimulationstests überprüft. Während der Behandlung konnte eine ausgeprägte Suppression der Nebennierenrindenfunktion, gekennzeichnet durch die signifkante Abnahme der basalen Cortisolkonzentration, auf weniger als 10 % der Ausgangswerte vor der Behandlung gemessen werden. Auch der ACTH-Stimulationstest am 8. Behandlungstag zeigte einen signifikant geringeren Anstieg des Kortisolspiegels (< 50 %) als vor der Behandlung. Weiterhin kam es während der dermalen Verabreichung von Dexamethason zu einer progressiven, signifikanten Zunahme des Serumglucosespiegels bis um das 1,5 fache des Kontrollwertes. Parallel dazu stieg der Plasmainsulinspiegel um das 3-fache des Ausgangswertes vor Behandlungsbeginn. Die Plasmakonzentration von T3 zeigte einen leichten behandlungsbedingten Abfall, wohingegen der Plasma-T4-Spiegel einen deutlichen Rückgang auf 50 % des Ausgangswertes zeigte. Die endokrinologischen Veränderungen waren nach Absetzen der Behandlung alle reversibel. Weiterhin kam es zu einer signifikanten Reduktion der eosinophilen Granulozyten und der Lymphozyten, während die Zahl der Neutrophilen zunahm. Plasmakonzentrationen von Dexamethason konnten mit einem Maximalwert am 8. Tag der Behandlung (1542,10 ± 567 pg/ml) gemessen werden. Diese Ergebnisse belegen, dass bei der dermalen Applikation von Dexamethason eine perkutane Wirkstoffresorption in einem Umfang stattfindet, dass die typischen systemischen Glucocorticoidwirkungen auftreten. Es kann somit auch davon ausgegangen werden, dass die topische Verabreichung schwach wirksamer Glucocorticoidformulierungen eine gewisse Dopingrelevanz besitzt.
28

Oral and Intravenous Itraconazole for Systemic Fungal Infections in Neutropenic Haematological Patients: Meeting Report

Prentice, H. Grant, Caillot, Denis, Dupont, B., Menichetti, F., Schuler, Ulrich January 1999 (has links)
Effective prevention, or treatment, of invasive fungal infection in the neutropenic patient has hitherto been unsatisfactory because of either an inadequate anti-fungal spectrum of the agent or important toxicity. Itraconazole is effective against a broad spectrum of the opportunistic pathogens seen in Europe and North America. Prior problems with absorption, e.g. in the marrow transplant recipient, have been overcome with the introduction of an oral solution and an i.v. preparation. The deliberations of an expert meeting held in June, 1998 include recommendations on which patient requires one of these new preparations based on clinical trials, the dose and route. Important drug interactions are also detailed. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
29

Systemische Wirkungen und Nebenwirkungen einer dermal verabreichten dexamethasonhaltigen Formulierung bei klinisch gesunden Pferden

Allersmeier, Maren 23 November 2010 (has links)
Da topische Glucocorticoide im Vergleich zur parenteralen Anwendung weniger systemische (Neben)Wirkungen haben können, werden sie bevorzugt in der Human- und Veterinärmedizin eingesetzt. Jedoch konnte bei vielen Untersuchungen gezeigt werden, dass topische Glucocorticoide je nach Applikationsdauer, -ort, Wirkstoffpotenz, -dosis und Behandlungsfläche ausgeprägte messbare Reaktionen wie Suppression der HHNA und der Immunzellen hervorrufen können. Beim Pferd wurden jedoch dahingehend bisher keine Untersuchungen durchgeführt. Da Glucocorticoide im Pferdesport auch dopingrelevant sind wurde der Frage nachgegangen, ob nach der dermalen Applikation eines niederpotenten Glucocorticoidpräparates auf die Haut gesunder Pferde systemische Effekte auftreten können und ob ein, nach perkutaner Resorption auftretender, Wirkstoffspiegel im Blut gemessen werden kann. Im Rahmen dieser Dissertation standen 10 erwachsene, klinisch gesunde Versuchspferde zur Verfügung. Die Versuchsdurchführung erfolgte in 3 Phasen. Vor Behandlungsbeginn (Tag 0) wurden von jedem Pferd die Kontrolldaten erfasst. Die Applikation der Dexamethasonformulierung erfolgte über einen Zeitraum von 10 Tagen. 2 mal täglich wurden 50 g einer 0,017 %igen Dexamethasonemulsion auf eine definierte Hautfläche (30 x 50 cm) aufgetragen. Die Blutentnahmen zur Gewinnung der Proben erfolgten am 2., 6., 8., und 10. Tag der Behandlung. Die Nachbehandlungsphase erstreckte sich über einen Zeitraum von 20 Tagen ohne die Dexamethasonanwendung. Hier erfolgte die Probengewinnung an den Tagen 3, 7, 11, 14 und 20 nach Absetzen der Behandlung. Aus den gewonnenen Plasmaproben wurden die Konzentrationen von Cortisol, Insulin, T3 und T4 mittels Radioimmunoassay bestimmt, sowie die ACTH-Konzentrationen mittels Chemilumineszenz-Enzymimmunometrischem Assay. Darüber hinaus wurden die hämatologischen und blutchemischen Parameter gemessen. Die Funktion des negativen Feetback-Mechanismus der Hypothalamus-Hypophysen-Nebennierenrinden-Achse wurde mittels eines ACTH-Stimulationstests überprüft. Während der Behandlung konnte eine ausgeprägte Suppression der Nebennierenrindenfunktion, gekennzeichnet durch die signifkante Abnahme der basalen Cortisolkonzentration, auf weniger als 10 % der Ausgangswerte vor der Behandlung gemessen werden. Auch der ACTH-Stimulationstest am 8. Behandlungstag zeigte einen signifikant geringeren Anstieg des Kortisolspiegels (< 50 %) als vor der Behandlung. Weiterhin kam es während der dermalen Verabreichung von Dexamethason zu einer progressiven, signifikanten Zunahme des Serumglucosespiegels bis um das 1,5 fache des Kontrollwertes. Parallel dazu stieg der Plasmainsulinspiegel um das 3-fache des Ausgangswertes vor Behandlungsbeginn. Die Plasmakonzentration von T3 zeigte einen leichten behandlungsbedingten Abfall, wohingegen der Plasma-T4-Spiegel einen deutlichen Rückgang auf 50 % des Ausgangswertes zeigte. Die endokrinologischen Veränderungen waren nach Absetzen der Behandlung alle reversibel. Weiterhin kam es zu einer signifikanten Reduktion der eosinophilen Granulozyten und der Lymphozyten, während die Zahl der Neutrophilen zunahm. Plasmakonzentrationen von Dexamethason konnten mit einem Maximalwert am 8. Tag der Behandlung (1542,10 ± 567 pg/ml) gemessen werden. Diese Ergebnisse belegen, dass bei der dermalen Applikation von Dexamethason eine perkutane Wirkstoffresorption in einem Umfang stattfindet, dass die typischen systemischen Glucocorticoidwirkungen auftreten. Es kann somit auch davon ausgegangen werden, dass die topische Verabreichung schwach wirksamer Glucocorticoidformulierungen eine gewisse Dopingrelevanz besitzt.
30

Validation of enhancer variants modulating haematological toxicity reactions / Validering av enhancer varianter som modulerar hematologiska toxicitetsreaktioner

Norberg, Zandra January 2022 (has links)
Omkring 20 miljoner nya cancerfall inträffar över hela världen varje år, och under 2020 uppskattades det att 10 miljoner dödsfall var förknippade med cancer. En av de vanligaste behandlingarna för cancer är cytostatika (cellgifter) som angriper alla snabbväxande celler. Detta kan i sin tur leda till allvarliga biverkningar, exempelvis hematologiska toxicitetsreaktioner som kan vara livshotande och till och med dödliga, men hur allvarligt en patient kommer att reagera på behandlingen är mycket individuellt. För närvarande finns det ingen definitiv förklaring på vad som är den bakom- liggande orsaken till dessa allvarliga toxicitetsreaktioner. Det kan vara en genetisk komponent och det antas att genetiska variationer finns i genomets regulatoriska sekvenser som kan vara bidragande faktorer. För detta examensarbete har det identifierats varianter som finns inom eller nära någon enhancer där motsvarande enhancer kan vara kopplad till gener relevanta för de allvarliga toxicitetsreaktioner som vissa patienter upplever. Syftet är att validera att dessa enhancers faktiskt reglerar genuttrycket av dessa gener genom CRISPR-interferens (CRISPRi). Genom att rikta in sig på de identifierade enhancer-varianterna med CRISPRi-systemet, med hjälp av flera olika sgRNA, skulle en mätbar förändring i genuttryck kunna uppnås. Den slutliga valideringen av dessa enhancers, om de faktiskt modulerar genuttrycket, har inte utförts på grund av tidsbrist. Dock  har  alla  nöd- vändiga komponenter förberetts såsom att integrera de erforderliga sekvenserna för CRISPRi till genomet av cancercellinjen K562 och sorterat ut de celler med framgångsrik integrering, därigenom skapat en stabil cellinje. / Around 20 million new cancer cases occur worldwide every year, and in 2020 alone it was estimated that 10 million deaths were associated with cancer. One of the most common treatments for cancer is the use of chemotherapy drugs which are nonspecific and target all fast dividing cells. This in turn can lead to serious haematological toxicity reactions among other adverse side effects that could be life threatening and even fatal, but how severely a patient will react to the treatment is very individual.  As of now there is no definite answer to what the underlying cause for these severe toxicity reactions is.  There could be a genetic component and it is hypothesised that there are variants residing in the regulatory sequences of the genome that could be contributing factors. For this degree project, variants that are located within or near an enhancer have been identified where the corresponding enhancer might be linked to genes relevant for why some patients might experience severe toxicity re- actions. The aim is to validate that these enhancers do in fact regulate the gene expression of these genes through the use of CRISPR-interference (CRISPRi). By targeting around the identified enhancer variants with the CRISPRi system, using several different sgRNA, there could be a measur- able change in gene expression. The final validation of the enhancers, if these do in fact modulate the gene expression, was not performed due to lack of time. However, all necessary components were prepared such as integrating the required sequences for CRISPRi into the genome of the cancer cell line K562 and sort for successful integration, thereby creating a stable cell line.

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