• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 217
  • 96
  • 94
  • 38
  • 38
  • 9
  • 6
  • 2
  • 1
  • 1
  • Tagged with
  • 511
  • 285
  • 115
  • 72
  • 58
  • 50
  • 50
  • 50
  • 38
  • 37
  • 34
  • 33
  • 33
  • 30
  • 30
  • 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.
371

Výpočtové modelování vysokofrekvenčního hluku v kabině letounu EV-55M / Computational modelling of high-frequency noise inside cabin of aircraft EV-55M

Straka, Martin January 2013 (has links)
This thesis describes methods of high frequency noise and vibrations computation of cabin part of EV–55M (aircraft developed by Evektor Kunovice). There is a brief summary of methods used for determining high frequency noise and vibrations in the first part of the thesis. Detailed explanation is given for Statistical Energy Analysis (SEA) which is nowadays the most dominant method in this area. The energy balance equation is derived in this chapter and SEA parameters such as modal density, damping loss factor, coupling loss factor and power input are introduced here. Next part deals with main noise sources of propeller driven and jet aircraft and passive and active noise controls are discussed. Practical part of this thesis deals with modeling aircraft EV–55M fuselage using VA One SEA module. Two models were created. First of them is only an outside fuselage with aircraft flooring and the second one is extended by interior trim panels and is applicable for simulation of noise control treatments. Computational modeling is accompanied by experimental measurement of passive noise control material characteristics. Postprocessing of information obtained from impedance tube measurement was performed in FOAM – X. Determined characteristics of porous material were used as inputs to VA One and reduction of sound pressure level in fuselage cavities by using noise control treatment was found. In conclusion there is a summary of noise transmission paths from sources to interior cavity and some treatments of them are simulated
372

Nové metabolické regulátory a prozánětlivé faktory v etiopatogeneze diabetes mellitus 2. typu a obezity: vliv farmakologických a dietních intervencí / Novel metabolic regulators and proinflammatory factors in the etiopathogenesis of type 2 diabetes mellitus and obesity: the influence of pharmacological and dietary interventions

Mráz, Miloš January 2011 (has links)
NOVEL METABOLIC REGULATORS AND PROINFLAMMATORY FACTORS IN THE ETIOPATHOGENESIS OF TYPE 2 DIABETES MELLITUS AND OBESITY: THE INFLUENCE OF PHARMACOLOGICAL AND DIETARY INTERVENTIONS MUDr. Miloš Mráz Doctoral Thesis ABSTRACT (EN) Identifying novel factors involved in the etiopathogenesis of obesity, diabetes mellitus and their complications has become one of the primary scopes of metabolic research in the last years. The aim of the present study was to evaluate the role of recently discovered metabolic and inflammatory regulators including fibroblast growth factors 19 and 21 and chemotactic cytokines in the development of obesity and type 2 diabetes mellitus (DM2). A total number of 182 patients were included into the study. They were divided into 3 groups - patients with obesity but without type 2 diabetes mellitus, individuals with obesity and type 2 diabetes mellitus and healthy control normal-weight subjects. Selected interventions included 2 to 3 weeks of very-low-calorie diet (VLCD - energy content 2500 kJ/day), 3 months of administration of PPARα receptor agonist fenofibrate and acute hyperinsulinemia during hyperinsulinemic isoglycemic clamp. Our results indicate that the increase of circulating FGF-21 levels after VLCD and fenofibrate treatment could contribute to positive metabolic effects of these...
373

Är genterapi medierad av adenoassocierat virus en effektiv och säker behandling mot hemofili A och B ur ett långsiktigt perspektiv? : En systematisk litteraturstudie / Is adeno-associated virus-mediated gene therapy a durable, effective and safe treatment for hemophilia A and B? : A systematic literature study

Landin, Linnéa January 2020 (has links)
Bakgrund - Hemofili A och B är X-kromosombundna blödarsjukdomar, som beror på genetiska avvikelser i de gener som kodar för koagulationsfaktor VIII respektive IX. I dagsläget förlitar sig hemofilipatienter på kontinuerliga intravenösa injektioner med faktorkoncentrat, för att förhindra att potentiellt livshotande blödningar uppstår. Genterapi med rekombinanta adeno-associerade virus (AAV) skulle kunna erbjuda ett kurativt behandlingsalternativ, genom införandet av friska arvsanlag i hepatocyter. Syfte - Syftet med den här litteraturstudien var att undersöka huruvida genterapi medierad av AAV-vektorer är en effektiv och säker behandling mot hemofili A och B ur ett långsiktigt perspektiv. Metod - Studien är genomförd som en systematisk litteraturstudie och är baserad på sex originalartiklar framsökta via databasen PubMed, med sökorden "hemophilia AND gene therapy". Specificerade sökkriterier användes för att underlätta relevansbedömning och valet av artiklar. Resultat - En ökad endogen koagulationsfaktorproduktion kunde påvisas hos majoriteten av studiedeltagarna efter genterapibehandlingarna. Sammantaget observerades också en väsentlig blödningsreducering och en minskad faktorkoncentratanvändning. Störst förbättring noterades i de kohorter som erhållit högre genterapidoser eller den muterade faktor IX Padua-genen. Ingen immunrespons mot transgenprodukten detekterades i någon studie. Däremot sågs ett humoralt immunsvar mot AAV-kapsiden hos samtliga studiedeltagare. En mycket stor variation i T-cellssvar mot AAV-kapsiden kunde noteras. Förhöjda nivåer av alaninaminotransferas (ALAT) var den vanligast förekommande incidenten, men samtliga fall kunde framgångsrikt behandlas med glukokortikoidpreparat. Slutsats - Genterapibehandling med rekombinanta AAV-vektorer mot hemofili A och B förefaller effektiv och säker. Förhöjda ALAT-nivåer återstår dock som en behandlingsproblematik. Längre uppföljningar av fler genterapibehandlade hemofilipatienter krävs, för att kunna dra några definitiva slutsatser, väga risker mot nytta, samt optimera och individanpassa doser. / Background - Hemophilia A and B are X-linked bleeding disorders, resulting from defects in the genes encoding coagulation factors VIII and IX respectively. The current treatment for hemophiliacs entails frequent intravenous injections of coagulation factor concentrates, to prevent potentially life-threatening hemorrhages. Gene therapy utilizing recombinant adeno-associated viruses (AAV) could offer a potentially curative treatment option through the introduction of healthy genes into hepatocytes. Aim - The aim of this literature study was to investigate the long-term efficacy and safety of AAV vector-mediated gene therapy for the treatment of hemophilia A and B. Methods - The study is conducted as a systematic literature study and is based on six original articles retrieved from the search engine PubMed, using the key words "hemophilia AND gene therapy". Specific search criteria were used to facilitate the relevance assessment and selection of articles. Results - An increased endogenous coagulation factor synthesis was noted in the majority of the study participants after the gene therapy. Overall, a significant reduction in bleeding episodes and the use of factor concentrates were observed. The greatest improvements were noted in the cohorts that received the higher gene therapy doses or the mutated factor IX Padua gene. None of the study participants had an immunologic response to the transgene product. A humoral immune response against the AAV capsid was seen in all participants though. Large differences in AAV capsid-specific T-cell activation were observed. The most common adverse event was an elevation in the alanine aminotransferase (ALT) level. However, these events could be controlled with glucocorticoids. Conclusions - AAV vector-mediated gene therapy for the treatment of hemophilia A and B had a positive efficacy and safety profile. Although increased ALT levels remain a concern. Monitoring of larger numbers of study participants for longer follow-up periods is necessary for any definite conclusions to be drawn, to weigh risks against benefits and to optimize individual dosing.
374

Prognostički značaj laboratorijskih pokazatelja uteroplacentalne cirkulacije kod trudnica sa hipertenzijom i preeklampsijom / Prognostic values of laboratory markers of uteroplacental circulation in pregnancies with hypertension and preeclampsia

Jakovljević Ana 21 September 2016 (has links)
<p>UVOD: Hipertenzivna oboljenja u trudnoći predstavljaju heterogenu grupu bolesti koja se javljaju kod 3-8% trudnica op&scaron;te populacije. Najteže forme ovih oboljenja preeklampsija, eklampsija i HELLP sindrom su vodeći uzročnici morbiditeta i mortaliteta majke i ploda u odnosu na sve druge komplikacije u trudnoći. Etiopatogeneza ovih oboljenja je jo&scaron; uvek nedovoljno razja&scaron;njena ali se smatra da placenta ima ključnu ulogu u nastanku ovih komplikacija, odnosno da placentalna insuficijencija, koja nastaje kao posledica nedovoljne adaptacije decidualnih i intramiometrijalnih delova spiralnih arterija već u prvih nekoliko nedelja trudnoće, dovodi do redukcije utero-placentalne cirkulacije i lokalne placentalne hipoksije, &scaron;to se nepovoljno održava i na majku i na plod. U cilju razja&scaron;njenja patofiziolo&scaron;kih mehanizama nastanka hipertenzivnih oboljenja u trudnoći i pronalaska dovoljno senzitivnih makera koji bi pomogli u ranom predviđanju nastanka najtežih formi ovih oboljenja, do sada su ispitivani brojni proteini koji učestvuju u procesima stvaranja i razvoja placentalne vaskularne mreže kao &scaron;to su vaskularni endotelni faktor rasta (VEGF-A), placentalni faktor rasta (PlGF) i solubilni receptor fms-like tirozin kinaza receptor (sFlt-1). CILJ: Uporediti serumske koncentracije (sFlt-1, PlGF, VEGF-A, PAPP-a, free&szlig;hCG, glukoze, ukupnog holesterola, HDL holesterola, LDL holesterola, triglicerida, apo-AI, apoB, AST, ALT, GGT, kreatinina, ureje, mokraćne kiseline, hsCRP, Na, K, Cl, P, Mg i Ca između grupe trudnica sa preeklampsijom, hroničnom i gestacijskom hipertenzijom i kontrolne grupe trudnica u prvom trimestru trudnoće između 11 i 14. nedelje gestacije. Ispitati da li se vrednosti odabranih laboratorijskih parametara (sFlt-1, VEGF-A i PLGF) kod ispitivanih trudnica statistički značajno razlikuju u odnosu na gestacijsku nedelju u trenutku porođaja, težinu i dužinu i APGAR skor bodovanja novorođenčeta. Ispitati da li se vrednosti angiogenih proteina:sFlt-1, VEGF-A, PlGF značajno razlikuju kod ispitivanih trudnica u odnosu na broj prethodnih trudnoća i starosti trudnica. MATERIJAL I METODE: Istraživanje je sprovedeno kao prospektivno analitička studija u Kliničkom centru Vojvodine, u periodu od juna 2012. do februara 2015. godine. U istraživanje je uključeno ukupno 143 trudnice starosti od 18 &ndash; 43 godine. Sve trudnice uključene u istraživanje podeljene su na dve ispitivane i jednu kontrolnu grupu. Prvu ispitivanu grupu činilo je 43 trudnice koje su po definisanim kriterijuma razvile preeklampsiju u aktuelnoj trudnoći. Drugu ispitivanu grupu činilo je 46 trudnica kojima je dijagnostikovana ili potvrđena hronična ili gestacijska hipertenzija u aktuelnoj trudnoći. Kontrolnu grupu činilo je 54 zdravih trudnica sa verifikovanim fiziolo&scaron;kim ishodom trudnoće u terminu, bez maternalnih i fetalnih komplikacija. Prilikom regrutovanja trudnica (između 11+0 i 13+6 nedelja gestacije) za uče&scaron;će u istraživanju, uzeti su anamnestički podaci o faktorima rizika za pojavu hipertenzivnih oboljenja u trudnoći, i u okviru kliničkog i aku&scaron;erskog pregleda urađena su antropometrijska merenja, merenje krvnog pritiska, i specijalizovani ultrazvučni pregled ploda radi utvrđivanja gestacijske starosti ploda i određivanja rizika za pojavu hromozomskih anomalija ploda. Trudnicama je nakon uzimanja anamnestičkih podataka i kliničkog i aku&scaron;erskog pregleda i potpisanog pisanog pristanka pacijenta o dobrovoljnom učestvovanju u istraživanju izvađena krv radi određivanja odabranih laboratorijskih parametara. Serumske koncentracije sFlt1, VEGF-A i PIGF određivane su kvantitativnom ELISA tehnikom (R&amp;D Systems Europe Ltd. Abingdon, UK), dok su: glukoza, ukupni holesterol, HDL holesterol, LDL holesterol, trigliceridi, apo-AI I apoB, AST, ALT, GGT, kreatinin, ureja, mokraćna kiselina, hsCRP, Na, K, Cl, Mg, P, Ca određivani na automatizovanim analizatorskim sistemima. Sve trudnice su kategorisane u 2 ispitivane i kontrolnu grupu na osnovu pojave ili isključenja hipertenzivnih oboljenja u aktuelnoj trudnoći. Statistička obrada podataka urađena je u statističkom programu STATISTICA 12 (StatSoft Inc.,Tulsa, OK, USA). Podaci su predstavljeni tabelarno i grafički, nivo statističe značajnosti p, je tumačen statistički značajnim ukoliko su vrednosti p&lt;0,05. REZULTATI: Vrednosti serumskih koncentracija sFlt-1 se statistički značajno razlikuju u sve tri grupe ispitanica i značajno su vi&scaron;e u grupama sa hipertenzivnim oboljenjima u odnosu na zdravu grupu ispitanica, p&lt;0,001. Serumske koncentracije VEGF-A su značajno niže u grupi trudnica sa preeklampsijom u odnosu na zdrave trudnice kontrolne grupe (p&lt;0,001), dok se nivoi serumskih koncentracija PlGF statistički značajno razlikuju između sve tri grupe trudnica tako da su najniže vrednosti uočene u grupi sa preeklampsijom (p&lt;0,001) u odnosu na preostale dve grupe ispitanica. Nije uočeno postojanje statistički značajne razlike u nivoima PAPP-A, biohemijskih parametara (glukoze, AST, ALT, GGT kreatinina, ureje, mokraćne kiseline), lipidskih parametara (uk. holesterol, LDL, apo A-I, apo B), parametara inflamatornog (kompletna krvna slika, fibrinogen), hemostaznog (D-dimer, vWF-antigen) i elektrolitskog statusa (Na, K, Cl, P, Mg), p&gt;0,05. Nivoi free &szlig;hCG i HDL holesterola su značajno niže, dok su vrednosti hsCRP i triglicerida značajno vi&scaron;e u grupi trudnica sa preeklampsijom u odnosu na grupu bez hipertenzivnih poremećaja u trudnoći. Serumske koncentracije sFlt-1 preko 865 pg/ml imaju senzitivnost od 93% i specifičnost od 81,5% u predviđanju nastanka preeklampsije, dok serumske koncentracije PlGF ispod 60 pg/ml senzitivnost od 88,4% i specifičnost od 79,6% u predviđanju pojave preeklampsije. Serumske koncentracije sFlt-1, VEGF-A i PlGF ne pokazuju statistički značajnu razliku u odnosu na godine života trudnice i broja prethodnih trudnoća p&gt;0,05. Serumske koncentracije sFlt-1 i PlGF se značajno razlikuju u odnosu na telesnu težinu novorođenčeta, tako da su niže vrednosti oba proteina detektovane u grupi novorođenčadi sa porođajnom težinom ispod 1500 gr. u odnosu na telesnu masu između 2800-3300 gr, p&lt;0,001. Takođe su nađene niže vrednosti sFlt-1 i PlGF u grupi trudnica koje su se porodile pre 33. nedelje gestacije u odnosu na nedelju gestacije u trenutku porođaja preko 37 nedelje gestacije, p&lt;0,001. Serumske koncentracije sFlt-1 i PlGF se značajno razlikuju u odnosu na indeks telesne mase majke tako da su vi&scaron;e vrednosti sFlt-1 i niže vednosti PlGF nađene u grupi trudnica sa indeksom telesne mase ispod 25 u odnosu na grupu trudnica sa indeksom telesne mase preko 30 kg/m2, p&lt;0,001. Serumske koncentracije sFlt-1 u prvom trimestru trudnoće su značajno povezane sa parametrima inflamacije (hsCRP), vrednostima dijastolnog krvnog pritiska i nivoima free &szlig;hCG. Takođe se uočava značajna povezanost koncentracije PlGF sa indeksom telesne mase, vrednostima sistolnog krvnog pritiska i koncentracijom hsCRP u prvom trimestru trudnoće. ZAKLJUČAK: Nivoi antiangiogenog proteina sFlt-1 su vi&scaron;e u grupi trudnica sa preeklampsijom u odnosu na grupu sa hroničnom i gestacijskom hipertenzijom i grupu trudnica bez hipertenzivnih poremećaja trudnoći. Nivoi proangiogenog proteina VEGF-A su značajno niže u grupi trudnica sa preeklampsijom i hroničnom i gestacijskom hipertenzijom u odnosu na grupu trudnica bez hipertenzivnih poremećaja u trudnoći. Serumske koncentracije proangiogenog proteina PlGF su niže u grupi trudnica sa preeklampsijom u odnosu na grupu sa hroničnom i gestacijskom hipertenzijom i grupu trudnica bez hipertenzivnih poremećaja trudnoći. Serumske koncentracije placentalnog proteina free &szlig;hCG i HDL holesterola su značajno niže, dok su vrednosti hsCRP i triglicerida značajno vi&scaron;e u grupi trudnica sa preeklampsijom u odnosu na grupu bez hipertenzivnih poremećaja u trudnoći. Između trudnica sa hipertenzivnim poremećajima u trudnoći i zdravih trudnica nije uočeno postojanje značajne razlike u vrednostima placentalnog proteina PAPP-A, biohemijskih parametara (glukoze, AST, ALT, GGT kreatinina, ureje, mokraćne kiseline), lipidskih parametara (uk. holesterol, LDL, apo A-I, apo B), parametara inflamatornog (kompletna krvna slika, fibrinogen), hemostaznog (D-dimer, vWF-antigen) i elektrolitskog statusa (Na, K, Cl, P, Mg). Serumske koncentracije sFlt-1 i PlGF se značajno razlikuju u odnosu na gestacijsku starost na porođaju i telesnu masu novorođenčeta i niže su kod trudnica koje su se prevremeno porodile kao i kod novorođenčati sa manjom porođajnom težinom. Serumske koncentracije sFlt-1 se značajno razlikuju u odnosu telesnu dužinu i APGAR skor novorođenčeta, tako da su vi&scaron;e vrednosti sFlt-1 udružene sa većom telesnom dužinom novorođenčeta i boljim APGAR skorom. Serumske koncentracije sFlt-1, VEGF-A i PlGF se ne razlikuju značajno u odnosu na godine života trudnice i broja prethodnih trudnoća. Nivoi proteina angiogeneze sFlt-1 i PlGF predstavljaju dobre prediktore u predviđanju nastanka preeklampsije u prvom trimestru trudnoće.</p> / <p>INTRODUCTION: Hypertensive disorders in pregnancy are a heterogeneous group of diseases that occur in 3-8% of all pregnancies. The most difficult forms of these diseases: preeclampsia, eclampsia and HELLP syndrome are the leading causes of maternal and fetal morbidity and mortality in relation to all other pregnancy complications. Etiopathogenesis of these diseases is still insufficiently understood but it is thought that the placenta plays a key role in the development of these complications, and that placental insufficiency, which occurs as a result of insufficient adaptation of decidual intramiometrial and parts of the spiral arteries in the first few weeks of pregnancy, leading to a reduction of utero- placental circulation and local placental hypoxia, which adversely affects the mother and the fetus. In order to elucidate the pathophysiological mechanisms of hypertensive disorders in pregnancy and to find sufficiently sensitive makers for early prediction of the most severe forms of these diseases, so far have been investigated a number of proteins involved in the processes of creation and development of placental vascular network such as vascular endothelial growth factor (VEGF-A), placental growth factor (PlGF) and soluble fms-like receptor tyrosine kinase receptor (sFlt-1). OBJECTIVE: The aim of the study was to compare serum concentration of sFlt-1, PlGF, VEGF-A, PAPP-A, free&szlig;hCG, glucose, total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides, apo-AI, apo B, AST, ALT, GGT, creatinine, urea, uric acid, hsCRP, Na, K, Cl, P, Mg and Ca between the group of pregnant women with preeclampsia, chronic and gestational hypertension and the control group of pregnant women in the first trimester of pregnancy between 11 and 14 weeks gestation. Also the aim was to examine whether the value of selected laboratory parameters (sFlt-1, VEGF-A and PlGF) differ in relation to gestational week at the time of birth, weight, length and APGAR scoring system of newborns. The aim was to examine whether the value of angiogenic proteins: sFlt-1, VEGF-A and PlGF differ significantly in relation to the number of previous pregnancies and age of the pregnant woman. MATERIALS AND METHODS: The study was conducted as a prospective analytical study in the Clinical Center of Vojvodina, in the period from June 2012 to February 2015. The study included a total of 143 pregnant women aged 18 - 43 years. All pregnant women included in the study were divided into two study and one control group. The first study group consisted of 43 pregnant women who developed preeclampsia during the current pregnancy. The second study group consisted of 46 pregnant women who are newly diagnosed or confirmed chronic or gestational hypertension during the current pregnancy. The control group consisted of 54 healthy pregnant women with verified physiological outcome of pregnancy at term without maternal and fetal complications. Patients were included in the study between 11 + 0 and 13 + 6 weeks of gestation. All patients had data about risk factors for developing hypertensive disorders in pregnancy. After clinical and obstetric examination all patients underwent anthropometric measurements, measurement of blood pressure, and specialized ultrasound examination to determine precise gestational age of the fetus and to determine the risk for fetal chromosomal abnormalities. All patients signed a written consent of the patient&#39;s voluntary participation in the study. Serum levels of sFlt1, VEGF-A and PlGF were determined by quantitative ELISA (R &amp; D Systems Europe Ltd., Abingdon, UK), while glucose, total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides, apo-AI, apo B, AST, ALT, GGT, creatinine, urea, uric acid, hsCRP, Na, K, Cl, P, Mg, Ca were determined on automated analyzer systems. All pregnant women were categorized into 2 study and a control group on the basis of presence of hypertensive disorders in the current pregnancy. Statistical analysis was performed in 12 statistical program STATISTICA (StatSoft Inc., Tulsa, OK, USA). The data are presented in tables and graphs, the level of significance p is interpreted statistically significant if the p value was less than &lt;0.05. RESULTS: Serum concentrations of sFlt-1 are statistically significantly different in all study groups and significantly higher in the groups with hypertensive disorders compared to healthy subjects p &lt;0.001. Serum levels of VEGF-A are significantly lower in the preeclampsia group compared to healthy control group (p &lt;0.001), while the levels of serum concentration of PlGF statistically significantly different between all groups so that the lowest values are observed in the preeclampsia group (p &lt;0.001) compared to the other two study groups. There is no statistically significant differences in the levels of PAPP-A, biochemical parameters (glucose, AST, ALT, GGT creatinine, urea, uric acid), lipid parameters (total cholesterol, LDL, apo AI, apo B), inflammatory parameters (complete blood count, fibrinogen), hemostatic (D-dimer, vWF-antigen) and electrolyte status (Na, K, Cl, P, Mg, Ca), p&gt; 0.05. Levels of free &szlig;hCG and HDL cholesterol levels are significantly lower, while the value of hsCRP and triglycerides significantly higher in the group of women with preeclampsia compared to the healthy control group. Serum concentrations of sFlt-1 over 865 pg/ml have a sensitivity of 93% and specificity of 81.5% in predicting preeclampsia, while serum PlGF concentration below 60 pg/ml, a sensitivity of 88.4% and a specificity of 79.6% in predicting preeclampsia. Serum concentrations of sFlt-1, VEGF-A and PlGF do not show a statistically significant difference compared to the age of pregnant women and the number of previous pregnancies p&gt; 0.05. Serum concentrations of sFlt-1 and PlGF are significantly different in relation to the weight of the newborn, so that the lower values of both proteins are in the group of infants with birth weight below 1500 gr. in relation to the body weight between 2800-3300 gr., p &lt;0.001. There is also lower concentrations of sFlt-1 and PlGF in a group with deliveries before 33 weeks of gestation compared to the deliveries after 37 week of gestation, p &lt;0.001. Serum concentrations of sFlt-1 and PlGF are significantly different in relation to the mother&#39;s body mass index so that the lower values of sFlt-1 and PlGF are in the group of women with a body mass index below 25 in relation to a group with a body mass index over 30 kg/m2, p &lt;0.001. Serum concentrations of sFlt-1 in the first trimester of pregnancy were significantly associated with the parameters of inflammation (hsCRP), diastolic blood pressure and levels of free &szlig;hCG. It is also observed a significant correlation between PlGF with a body mass index, systolic blood pressure and hsCRP concentration in the first trimester of pregnancy. CONCLUSION: The levels of anti-angiogenic protein sFlt-1 are higher in the group of pregnant women with preeclampsia than in the group with chronic and gestational hypertension and the control healthy group. Levels of proangiogenic VEGF-A protein are significantly lower in the preeclampsia group and group with gestational and chronic hypertension compared to the control group. Serum levels of proangiogenic PlGF protein are significantly lower in the preeclampsia group than in the group with chronic and gestational hypertension and the control group. Serum concentrations of placental protein free &szlig;hCG and HDL cholesterol are significantly lower, while the value of hsCRP and triglycerides significantly higher in the preeclampsia group compared to the control group. Among pregnant women with hypertensive disorders in pregnancy and healthy pregnant women there are no significant differences in the values of placental PAPP-A protein, biochemical parameters (glucose, AST, ALT, GGT creatinine, urea, uric acid), lipid parameters (total cholesterol, LDL, apo AI, apo B), inflammatory parameters (complete blood count, fibrinogen), hemostatic (D-dimer, vWF-antigen) and electrolyte status (Na, K, Cl, P, Mg, Ca). Serum concentrations of sFlt-1 and PlGF are significantly different in relation to gestational age at delivery and newborn body weight and are lower in group with preterm delivery and newborns with lower birth weight. Serum concentrations of sFlt-1 are significantly different compared to body length and Apgar score, so that the higher values of sFlt-1 are associated with better outcome of newborns (greater body length and better APGAR score). Serum concentrations of sFlt-1, VEGF-A and PlGF are not different significantly with respect to age of pregnancy and the number of previous pregnancies. The levels of sFlt-1 and PlGF represents helpful markers in prediction of preeclampsia in the first trimester of pregnancy.</p>
375

Zeemanův jev v polovodičových kvantových strukturách / Zeemanův jev v polovodičových kvantových strukturách

Stráský, Josef January 2011 (has links)
This theoretical thesis presents detailed study of negatively charged excitons - trions - confined in single quantum well in presence of perpendicular magnetic field. Complex valence band of GaAs/GaAlAs compound is described within Luttinger Hamiltonian framework. Singlet and triplet states of negative trion are introduced. Advanced theoretical analysis of Zeeman effect for different states of trion is performed. Landau gauge of magnetic field and unusual wavefunctions basis is chosen and its accuracy is tested. Evolution of ground state energy and photoluminescence spectra with magnetic field is evaluated for different values of Landé g-factors. Probability of occurrence of electrons with respect to the hole position and their spatial correlation function are investigated.
376

Optimalizace expresního systému HEK293 buněčné linie pomocí regulace buněčného cyklu a apoptózy / Optimization of HEK293 cell line expression system by regulation of cell cycle and apoptosis

Poláchová, Edita January 2014 (has links)
Transient transfection of mammalian cell lines is an effective approach for recombinant protein production, which can provide milligrams to grams of proteins in two weeks from cloning of the corresponding cDNA. Native glycosylated proteins prepared via this approach can be used for various purposes in molecular biology, immunology or pharmaceutical industry, i.e. initial phase of pre-clinical therapeutic protein research. One of the most used mammalian host cell lines is the human embryonic kidney cell line, that can be easily cultivated and chemically transfected. The amount of proteins produced by transiently transfected human embryonic kidney cells can be enhanced by a whole range of factors, i.e. co-expression or direct addition of acidic fibroblast growth factor to the culture medium, co-expression of cell cycle regulating proteins or anti-apoptotic proteins. Expression plasmid pTW5 was prepared and further modified by gene insertion of aFGF, cell cycle regulator p18, p21 or p27 (cyclin-dependent kinase inhibitors) or apoptosis inhibitor bcl-2 or bcl-x. These plasmids were then used for optimization of HEK293T cell line expression system. The impact of every single regulator and their combinations, including hitherto undescribed effect of combination of cell cycle regulator and anti-apoptotic...
377

Vliv dávkování genu Nkx2.5 na vývoj a elektrofyziologii srdce u myši / Role of Nkx2.5 on development and electrophysiology of the mouse heart

Hámor, Peter January 2015 (has links)
Role of Nkx2.5 on development and electrophysiology of the mouse heart Prague 2015 Bc. Peter Hámor ABSTRACT The objective of this thesis is to investigate the role of Nkx2.5 gene dosage on electrophysiology of the mouse heart in prenatal stage of its development, in which the physiological functions of the heart fail to function properly. The main goal of this work is to search for differences in conduction of electric impulses through the embryonic mouse heart according to their genotype. Special method of capturing the conduction of electric impulse through myocardium was used for this purpose, called optical mapping. Thanks to this method I was able to construct images and videos capturing transition of the impulse with marked beginning of the activation and its direction in the heart. These outputs, or optical maps, help to define anomalies and defects compared with a normal functioning heart. The thesis focuses on the expression of the transcription factor Nkx2.5 and regulatory components related with the correct formation and physiology of the heart until 9.5 days post coitum. Individuals in this developmental stage were optically mapped and compared according to their genotypes - homozygous non-mutant, heterozygote and homozygous mutant mouse embryos exhibited some degree of similarity, while other...
378

Solution of General Stress Concentrators in Anisotropic Media by Combination of FEM and the Complex Potential Theory / Solution of General Stress Concentrators in Anisotropic Media by Combination of FEM and the Complex Potential Theory

Ševeček, Oldřich January 2009 (has links)
Disertační práce se věnuje problematice obecných koncentrátorů napětí v anisotropních prostředích. Zejména se jedná o problém trhlin končících na rozhraní dvou různých materiálů, či problém obecného více-materiálového klínu. Cílem práce je vytvořit komplexní nástroj pro posuzování obecných koncetrátorů napětí tj, popis pole napětí v jeho okolí, zahrnutí případného vlivu přemostění trhliny do výsledného pole napětí a definici lomových kritérií pro obecný koncentrátor v anisotropním prostředí. U popisu pole napětí je využit tzv. Lechnického-Strohův formalismus a technika spojitě rozložených dislokací využívající teorii komplexních potenciálů. V práci je rovněž široce uplatněn tzv. dvoustavový "psí"-integrál (pro výpočet různých součinitelů asymptotického rozvoje pro napětí), založený na Bettiho recipročním teorému v kombinaci s metodou konečných prvků. Pro formulaci lomových kritérií je použita teorie tzv. „konečné lomové mechaniky“ a teorie sdružených asymptotických rozvojů. Studován je především vztah mezi ohybem trhliny podél rozhraní a její případnou pentrací do základního materiálu. Veškeré potřebné výpočty jsou prováděny v matematických softwarech MAPLE 10.0, MATLAB 7.1 a konečnoprvkovém systému ANSYS 10.0.
379

Bedeutung der Alloantigen-unabhängigen Faktoren in der Frühphase nach tierexperimenteller Nierentransplantation

Hoff, Uwe 22 April 2005 (has links)
Die Schädigung des Organs durch Ischämie-Reperfusion (IR) im Rahmen der kadaverischen Organtransplantation hat bedeutenden Anteil an der Pathogenese verzögert einsetzender Organfunktion und Auswirkungen auf das Langzeitüberleben des Transplantats. In der vorliegenden Studie sollte der Einfluss unspezifischer Schädigung durch IR verglichen mit spezifischen Alloantigen-abhängigen Mechanismen während der Frühphase nach der Transplantation sowie die Auswirkungen prolongierter Aufbewahrung auf Schädigung und Immunogenität des Organs ermittelt werden. Nach vorausgegangener vierstündiger kalter Ischämiezeit wurden Organe aus syngen (Lew/Lew) und allogen (F344/Lew) transplantierten Ratten an 8 aufeinander folgenden Zeitpunkten innerhalb der ersten 10 Tage zu funktionellen, immunhistochemischen und morphologischen Veränderungen untersucht. In weiteren Gruppen wurden syngen transplantierte Organe 24 Stunden nach der Transplantation untersucht, die zuvor ansteigenden kalten Ischämiezeiten zwischen 2 und 48 Stunden ausgesetzt wurden. Im zeitlichen Verlauf zeigten sich bis 7 Tage nach der Transplantation keine wesentlichen Unterschiede zu Nierenfunktion, Morphologie, Zellinfiltration und Expression von Adhesionsmolekülen zwischen allogenen und isogenen Gruppen. Die zunächst eintretende Verschlechterung der Nierenfunktion war begleitet von einem Einstrom neutrophiler und monozytärer Zellen und morphologischen Veränderungen im Sinne von akuter Tubulusnekrose (ATN). Unter zunehmender Infiltration von Monozyten/Makrophagen kam es funktionell und morphologisch zur Regeneration. Neutrophile traten vornehmlich über Interaktion von ICAM-1/LFA-1 und Monozyten/Makrophagen über VCAM-1/VLA-4 aus dem Gefäßsystem aus. Gabe von Cyclosporin A führte zu signifikanter Reduktion ED-1-positiver Makrophagen nach 10 Tagen, ohne jedoch den Anteil des aktivierten Makrophagensubtyps ED-2 zu beeinflussen. Ansteigende kalte Aufbewahrung des Organs führte zu größerer vaskulärer Schädigung, die sich durch abnehmende Intensität und lückenhaftere Verteilung von PECAM-1 auf dem Endothel äußerte. Die Zunahme der Intensität von Tissue Factor auf Endothel und infiltrierenden Leukozyten deutete neben gesteigerter Thrombogenese auf alternative Adhäsionsmechanismen hin. Diese Ergebnisse zeigen, dass innerhalb der ersten 10 Tage nach der Transplantation wichtige Phasen der Gewebeschädigung und Regeneration ausgelöst durch die Schädigung nach IR und weitestgehend ohne Beteiligung Alloantigen-abhängiger Faktoren ablaufen. Eine bedeutende Rolle als Mediatoren während dieser Phasen kommt dabei den Monozyten/Makrophagen zu. / Organ damage due to long cold preservation is associated with delayed graft function and has important effects on graft survival. Aim of this study was to determine the impact of ischemia-reperfusion (IR) injury compared to antigen-specific mechanisms and the effect of prolonged cold ischemia on intragraft injury and antigenicity during the early phase post transplantation. Rat renal grafts were four-hours cold-preserved, transplanted to syngeneic (Lew/Lew) or allogeneic recipients (F344/Lew) and harvested at 8 different time points after transplantation for further investigation of functional, immunhistochemical and histologic changes. In five additional syngen groups organs were cold preserved from 2 hours to 48 hours and harvested after 24 hours post transplantation. No significant differences in renal function, morphologic changes, cellular infiltration and expression of adhesion molecules occurred between syngeneic and allogeneic groups within the first 7 days. Initial functional impairment was accompanied by the influx of neutrophils and monocytes/macrophages together with morphologic changes reflecting acute tubular necrosis (ATN). Increasing infiltration of monocytes/macrophages paralleled functional and morphologic regeneration. Extravasation of neutrophils was mediated mainly by interaction of ICAM-1/LFA-1 and infiltration of monocytes/macrophages by VCAM-1/VLA-4. Treatment with the standard dose of Cyclosporin A (CsA) lead to a significant decrease of ED1-positive macrophage infiltration 10 days post NTx but the portion of ED2-positive macrophage subtype was not affected. Prolonged cold organ preservation lead to more severe vascular damage indicated by decreased color intensity and continuity of PECAM-1 staining on endothelial cells. Higher staining intensity for Tissue Factor (TF) on endothelium and infiltrating leukocytes implicated enhanced intragraft procoagulant capacity and alternative adhesion mechanisms. These results show that within the first 10 days post transplantation phases of tissue injury and repair after ischemia-reperfusion are largely independent of the immunologic background and monocytes/macrophages play an important role as mediators during these processes.
380

Mechanisms underlying the regulatory function of tumor necrosis factor-alpha in skin inflammation

Kumari, Vandana 04 January 2015 (has links)
Die Haut ist das größte Organ des Menschen und bildet die Barriere gegenüber Einwirkungen aus der Umwelt. Die Störung der Hautbarriere durch exogene und endogene Reize führt zu einer Entzündungsreaktion in der Haut. In der Folge können Hauterkrankungen wie die irritative oder Atopische Dermatitis entstehen. Der Tumor Nekrose Faktor-α (TNF-α) ist ein pleiotrop wirksames Zytokin, das eine zentrale Rolle bei entzündlichen Prozessen spielt. Ziel der vorgelegten Promotionsarbeit war zu untersuchen, ob und wie TNF-α zu Entzündungsgeschehen, ausgelöst durch exogene und endogene Faktoren, beiträgt. Die Bedeutung von TNF-α wurde in TNF-ko Mäusen in verschiedenen Hautmodellen untersucht. Für das Irritationsmodell wurden chemische und physikalische Reize verwendet. TSLP (Thymic stromal lymphopoietin) wurde durch die verschiedenen Stimuli signifikant induziert. Diese Induktion war unabhängig von der endogenen TNF-α Produktion, gezeigt durch den Einsatz von TNF- ko Mäusen . Da endogenes TNF-α für die Hautirritation keine notwendige Bedingung darstellte, wurde die Bedeutung von TNF-α bei der atopischen Dermatitis (AD) untersucht. TNF-α defiziente Mäuse zeigen verstärkt Ekzeme im Vergleich zu Wildtyp Mäusen. Die Behandlung von TNF-ko Mäusen mit einem TSLP Antikörper führte zu einer Verminderung des Ekzems. Mastzellen wurden vermehrt in läsionaler Haut gefunden und korrelierten mit dem Schweregrad des atopischen Ekzems sowie der TSLP-Expression. / The skin is the largest organ of an individuum and builds the barrier for a host against the environment. Skin barrier disruption by exogenous or endogenous stimuli can lead to skin inflammation. As a consequence, irritant or atopic eczema, frequent skin diseases, may evolve. Tumor necrosis factor-α (TNF-α) is a pleiotropic cytokine which plays a central role in inflammatory processes. The main aim of this thesis was to clarify whether and how endogenous TNF-α is contributing to skin inflammation driven by exogenous and endogenous triggers. The role of endogenous TNF-α was studied using TNF knockout (-/-) mice. In an irritation model, chemical and physical stimuli were applied on to mouse skin. Thymic stromal lymphopoietin (TSLP) was significantly induced by the used irritants. This TSLP induction was independent from endogenous TNF-α proven by using TNF-/- mice. Next the role of TNF-α in atopic dermatitis (AD) promoting an allergic skin inflammation was investigated. TNF-/- mice developed more severe AD compared to the wildtype mice and TSLP was significantly increased and correlated with the severity of the eczema. To prove the pathophysiological role of TSLP for AD progression, TNF-/- mice were pretreated with an TSLP antibody. Indeed, these mice developed less AD symptoms compared to the control mice. Mast cells (MCs) were also significantly increased in lesional skin in the AD model and moreover, correlated with AD severity, but also with TSLP expression.

Page generated in 0.0439 seconds