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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.
1021

Evaluation der Aktivierung von CD4+ T-Lymphozyten bei Patienten mit Sepsis und akutem Nierenversagen / Time course of CD4+ lymphocyte adenosine triphosphate in sepsis with and without acute kidney injury.

Brier, Maria 14 January 2015 (has links)
No description available.
1022

Bio-engineering of muscle tissue in culture: influence of neural, cartilage or kidney cells and the effect of retinoic acid on muscle cell growth.

Grey, Matthew 23 December 2011 (has links)
Skeletal muscle fibers develop from mono-nucleated myoblasts that fuse to form multinucleated myotubes. In embryonic growth, this process occurs concurrently with the formation of the early cartilaginous skeleton and innervation by migrating nerve cells. The goal of my research was to explore co-culture conditions that encourage proliferation, differentiation and maturation of myoblasts to myotubes. A variety of co-culture experiments tested the influence of three basic tissues types (murine neural, cartilage and kidney primary cells) on the formation of myotubes in the C2C12 myoblast cell line. Three plating strategies were used: 1) C2C12 myoblasts were plated first, grown for two days before the addition of a second cell type; 2) both cell types were mixed and plated simultaneously; and 3) C2C12 myoblasts were added to a pre-established, 10 day old neural, cartilage or kidney cell culture. In addition, a parallel set of experiments were treated with all-trans retinoic acid, a potent myogenic activator and embryonic patterning signaling molecule. Myotube formation was consistently highest in C2C12 and cartilage co-cultures across all three plating strategies with a 277% increase in myotube area compared to controls. These effects were further enhanced when grown in 1 µg/mL all-trans retinoic acid. Co-cultures with neural or kidney cells consistently exhibited fewer myotubes when compared to C2C12 controls. It is postulated that the enhanced muscle growth in cartilage co-cultures was due to a chondrocyte-secreted extracellular matrix that facilitated myotube attachment to the substratum. / Graduate
1023

Eksperimentinio nefrotoksiškumo modelio in vivo sukūrimas ir jo taikymas kamieninių ląstelių tyrimuose / Development of Experimental Nephrotoxicity Model in vivo and Its’ Application to Stem Cells Research

Svitojūtė, Eglė 18 June 2012 (has links)
Pagrindinis tyrimo tikslas buvo sukurti eksperimentinį nefrotoksiškumo modelį in vivo ir įvertinti jo pritaikomumą ikiklinikiniuose kamieninių ląstelių tyrimuose. Nefrotoksiškumo modeliui parinkti 9–12 sav. amžiaus Wistar linijos žiurkių patinai. Eksperimento metu gyvūnai buvo laikomi individualiuose metaboliniuose narvuose esant pastovioms aplinkos sąlygoms. Inkstų pažeidimui sukelti parinktas gentamicino sulfato injekcinis tirpalas 40mg/1ml, kai jo dozė 80 mg/kg/d i. p. 7 dienas. Sudarytos trys laboratorinių gyvūnų grupės: I – kontrolinė grupė (1.5 ml 0.9 proc. NaCl tirpalo injekcijos i. p. 14 dienų), II – terapinė grupė (gentamicino injekcijos i. p. 14 dienų, dozė 5 mg/kg/d), III – pažeidimo grupė (gentamicino injekcijos i. p. 7 dienas, dozė 80 mg/kg/d). Vertinti žiurkių fiziologiniai, elgesio, biocheminiai šlapimo ir kraujo, frakcinės ekskrecijos, glomerulų filtracijos greičio ir histologiniai inkstų rodikliai. Visi rodikliai lyginti tarp trijų grupių. Laboratoriniams gyvūnams paskirta toksinė gentamicino dozė i. p. 80 mg/kg/d 7 dienas iš eilės sukėlė funkcinius ir morfologinius inkstų pokyčius, t. y. ūminį inkstų funkcijos pažeidimą, kurio pasireiškimą statistiškai patikimai (p<0.05) atspindėjo fiziologiniai, elgesio, biocheminiai kraujo ir šlapimo, frakcinės ekskrecijos, glomerulų filtracijos greičio ir histologiniai inkstų rodikliai lyginant su tais pačiais kontrolinės ir terapinės grupių žiurkių rodikliais. Sukurtas nefrotoksiškumo modelis pritaikytas bandomojo... [toliau žr. visą tekstą] / The main objective of this study was to develop experimental nephrotoxicity model in vivo and to assess its’ applicability for stem cell research. 9–12 weeks old male Wistar rats were chosen for the establishment of this model. During the experiment rats were housed in individual metabolic cages and maintained under standard conditions. Gentamicin sulphate solution for injection (40mg/1ml) was chosen as a toxicant. Toxic dose – genamicin 80 mg/kg/d i. p. for 7 consecutive days. 3 groups were constituted for the study: I group – control group (i. p. injection of saline 1.5 ml for 14 consecutive days), II group – therapeutic group (i. p. injection of genamicin 5mg/kg/d for 14 consecutive days), III group – acute kidney injury group (i. p. injection of genamicin 80mg/kg/d for 7 consecutive days). We evaluated physiological parameters, behavioural parameters, biochemical urine and blood parameters, fractional excretion parameters, glomerular filtration rate and histological kidney parameters. All parameters were compared between groups. Gentamicin administration in a very high dose (80 mg/kg/d i. p. for 7 consecutive days) caused functional and morphological renal changes and induced acute kidney injury, which was marked by statistically significant changes of physiological, behavioural, biochemical, fractional excretion, glomerular filtration rate and histological parameters, comparing with the same parameters of control and therapeutic groups. Nephrotoxicity model was applied... [to full text]
1024

Kavos rūgšties fenetilo esterio poveikio inkstų mitochondrijoms tyrimas / The effect of caffeic acid phenethyl ester on kidney mitochondria

Baranauskaitė, Agnė 18 June 2014 (has links)
Tyrimo tikslas: ištirti kavos rūgšties fenetilo esterio (CAFE) poveikį išemijos paveiktų žiurkės inkstų mitochondrijų funkcijoms. Uždaviniai: įvertinti tiesioginį in vitro CAFE poveikį inkstų mitochondrijų funkcijoms; CAFE poveikį išemijos (20 min) in vitro paveiktų inkstų mitochondrijų funkcijoms; kvėpavimo grandinės I komplekso aktyvumui; mitochondrijų gebėjimui kaupti Ca2+. Metodai. Wistar veislės žiurkių patinėliai buvo skirstomi į 4 grupes: kontrolinė grupė, 20 min trukmės išemijos, CAFE 22 mg/kg ir CAFE 34 mg/kg. CAFE buvo leidžiamas 1,5 h prieš sukeliant išemiją. Mitochondrijos buvo išskiriamos diferencinio centrifugavimo būdu. Mitochondrijų kvėpavimo greitis mitochondrijoms oksiduojant I ir II komplekso substratus buvo registruojamas poliarografiškai Klarko tipo elektrodu. Ca2+ sugėrimas buvo matuojamas fluorimetriškai. Mitochondrijų kvėpavimo grandinės I komplekso aktyvumas buvo tiriamas spektrofotometriškai. Rezultatai: CAFE (0,7 – 4,5 M) didina mitochondrijų kvėpavimo greitį 2-oje metabolinėje būsenoje nuo 15 % iki 34 % ir neveikė mitochondrijų kvėpavimo greičio 3-ioje metabolinėje būsenoje (VADP). Didesnės koncentracijos (5,2 - 6,5 µM) slopina mitochondrijų kvėpavimo greitį VADP (16 % ir 43 % atitinkamai). Tiriant CAFE poveikį 20 min išemijos in vitro paveiktų mitochondrijų funkcijoms, nustatyta, jog 22 mg/kg ir 34 mg/kg CAFE, intraperitonealinė injekcija 1,5 h prieš sukeliant inkstų išemiją, 20 % (p<0,05) pagerino mitochondrijų kvėpavimo greitį VADP bei... [toliau žr. visą tekstą] / The aim of investigation: to analyse the effect of caffeic acid phenethyl ester (CAPE) on kidney mitochodrial functions. Objectives: to evaluate direct in vitro effect of CAPE on kidney mitochondrial functions; the impact of CAPE on ischemia (20 min) in vitro affected kidney mitochondrial functions; on the mitochondrial respiratory chain complex I activity and on the mitochondria capability to accumulate Ca2+. Methods. Wistar rats were pretreated intraperitoneal with 22 mg/kg and 34 mg/kg of CAPE. Animals were divided into 4 groups: control group, 20 min of ischemia, CAPE 22 mg/kg group and CAPE 34 mg/kg group. Mitochondria were isolated by means of differential centrifugation. The mitochondrial respiration rate while oxidizing complex I and II dependent substrates was registered polarographically with Clark-type electrode. Ca2+ accumulation was measured fluorometrically. Activity of complex I was measured spectrophotometrically. Results: the results shown that CAPE 0,7 - 4,5 µM increases mitochondrial State 2 respiration rate by 15 - 34 % and has no effect on the State 3 respiration rate. Higher concentrations (5,2 - 6,5 µM) decreased mitochondrial State 3 respiration rate by 16% and 43%, respectively. Pretreatment with CAPE (22 mg/kg and 34 mg/kg) increased (by 20%) the ischemia suppressed mitochondrial State 3 respiration rate and respiratory control index. CAPE had no effect on succinate oxydation. Pretreatment with CAPE (22 mg/kg and 34 mg/kg) increased Ca2+... [to full text]
1025

The Utility of Contrast-enhanced Ultrasound in the Assessment of Solid Small Renal Masses

Tabatabaeifar, Leila 19 March 2013 (has links)
Purpose: To compare hemodynamic of malignant and benign SRMs on CT and CEUS. Method: Seventy biopsy proven SRM underwent CEUS. Sixty-three had CT. After injection of 0.2 ml of Definity, 3min and after 0.9 ml infusion, 30 sec of data were acquires. Lesion hemodynamics relative to the cortex was evaluated both qualitatively and quantitatively. Results: Considering 15 and 20 HU as enhancement threshold, 10% to 13% of patients did not enhance on CT, while all lesions enhanced on CEUS. Papillary RCCs showed hypovascularity with 100% specificity. In other RCCs, PI, WI slope 5 to45%, 50 to100%, 10 to 90%, WO slope 100 to 50%, 100 to 10%, WO intensity at peak+30 seconds were statistically higher than benign SRMs. Conclusion: All solid SRMs enhance on CEUS, while CT does not show vascularity in 10-13% of solid SRMs. CEUS can differentiate malignant from benign SRMs by evaluating their hemodynamics.
1026

The Role of ALK3 in Urogenital Development

Di Giovanni, Valeria 15 February 2011 (has links)
The mammalian kidney and reproductive systems both derive from a common embryological origin, the intermediate mesoderm. Abnormal intermediate mesoderm development can result in congenital abnormalities of the urogenital system, yet the molecular mechanisms that govern intermediate mesoderm development are incompletely defined. The spatial and temporal expression of the proteins BMP2 and 4 and their receptor ALK3, in urogenital tissue, suggests a function for BMP-ALK3 signaling in the intermediate mesoderm. It was found that Alk3IM null kidneys display renal hypoplasia, associated with a decrease in kidney size and nephron number. The phenotype of renal hypoplasia in Alk3IM nulls was associated with early decreased number of developing nephron structures and secondary defects in branching morphogenesis. While neither apoptosis nor cell proliferation differed in metanephric mesenchyme cells in Alk3IM nulls, markers of renal progenitor cells were decreased in mutant animals. It was observed that Alk3 expression in the intermediate mesoderm also controls mesonephric tubule number. Alk3IM nulls had fewer mesonephric tubules and fewer derivative Leydig cells. The reduction in Leydig cells resulted in decreased levels in serum testosterone and defects in seminal vesicle formation and fertility. Alk3 expression was also required for normal development of the corpus epididymis. The morphological defects in nephrogenesis were associated with decreased phospho-p38 MAPK expression and in the testis with decreased Phospho-SMAD1/5/8. These results elucidated a requirement for Alk3 signaling in controlling progenitor cells derived from the intermediate mesoderm.
1027

Role of Vascular Endothelial Growth Factor-A in Diabetic Kidney Disease

Sivaskandarajah, Gavasker 25 August 2011 (has links)
Vascular endothelial growth factor-A (VEGF) is required for endothelial cell differentiation and survival. To investigate the renoprotective properties of VEGF in diabetes an inducible Cre-loxP gene targeting system was used to excise VEGF from podocytes of adult mice (VEGFKO). Diabetes was induced by streptozotocin (STZ) at 2.5 weeks of age and VEGFKO was induced by doxycycline (dox) at 3-4 weeks of age. Blood and urine were collected weekly to monitor for hyperglycaemia and proteinuria, respectively. Mice were dissected 8 weeks after diabetes induction or earlier if morbidly ill; twenty percent of the mice in the DM+VEGFKO group died before the surrogate endpoint. Glomerular VEGF mRNA expression was decreased in VEGFKO mice compared to controls. However, DM+VEGFKO mice had significantly greater proteinuria, degrees of glomerular sclerosis, and glomerular cell apoptosis. These results confirm that VEGF is normally upregulated in diabetes but reducing VEGF expression in diabetes causes severe kidney injury.
1028

Corticosteroidogenesis as a Target of Endocrine Disruption for the Antidepressant Fluoxetine in the Head Kidney of Rainbow Trout (Oncorhynchus mykiss)

Stroud, Pamela A 11 January 2012 (has links)
Fluoxetine (FLX), the active ingredient of Prozac™, is a member of the selective serotonin reuptake inhibitor (SSRI) class of anti-depressant drugs and is present in aquatic environments worldwide. Previous studies reported that FLX is an endocrine disruptor in fish, bioconcentrating in tissues including the brain. Evidence implicates that serotonin influences the activity of the hypothalamo-pituitary-interrenal (HPI) stress axis, thus exposure to FLX may disrupt the teleost stress response. This study examined in vitro cortisol production in rainbow trout (Oncorhynchus mykiss) head kidney/interrenal cells exposed to FLX and 14C-pregnenolone metabolism in head kidney microsome preparations of FLX-exposed trout. Results indicated that cells exposed in vitro to increasing concentrations of FLX had lower cortisol production and cell viability (versus control) and microsomes isolated from trout exposed to 54 μg/L FLX had higher pregnenolone metabolism versus those of control and low FLX-exposed (0.54 μg/L) trout.
1029

Investigations of Influenza Vaccination in Kidney and Lung Transplant Populations

Bergeron, Amber 06 1900 (has links)
These two studies investigate the immune responses of lung and kidney transplant recipients to the influenza vaccine. The study involving kidney transplant recipients developed a novel flow cytometry assay to measure cell-mediated immunity in response to influenza vaccination. The activation of T-cells was assessed through the change in T-cell production of interferon gamma after vaccination. In lung transplant recipients, the study examined the formation of de novo anti-HLA antibodies following influenza vaccination. Anti-HLA antibodies were classified as donor-specific or not. The study in kidney transplant recipients found that the influenza vaccine is effective at stimulating the immune response and producing long-lived memory in these patients, as evidenced by high baseline T-cell activity. The study of lung transplant recipients found that receiving the influenza vaccine did not result in the production of anti-HLA antibodies. Both studies found vaccine to be safe for use in these populations. / Experimental Medicine
1030

Renal proximal tubular handling of nucleosides by human nucleoside transporter proteins

Elwi, Adam 11 1900 (has links)
Human cells possess multiple nucleoside transporters (NTs) that belong to either the human equilibrative or concentrative NT (hENT: hENT1/2/3/4; hCNT: CNT1/2/3) families. In the kidney, coupling of apical hCNT3 activities to basolateral hENT1/2 activities is hypothesized to mediate renal nucleoside proximal tubular absorption while apical ENT1 may have a role in secretion. The overall aim of this research was to increase understanding of the roles of hENTs and hCNTs in renal handling of physiological nucleosides and anti-cancer nucleoside analog drugs. This was achieved by investigating the distribution of hENTs and hCNTs in human kidney tissue and the function of hENTs and hCNTs in cellular uptake and transepithelial fluxes of nucleosides in cultured human renal proximal tubule cells (hRPTCs). Immunolocalization of hCNT3 and hENT1 in human kidney tissue revealed that hENT and hCNT3 were present in apical membranes of proximal tubules. Production and characterization of adherent hRPTC cultures demonstrated endogenous hCNT3, hENT1, and hENT2 activities. These results provided evidence for the involvement of hCNT3, hENT1, and hENT2 in renal handling of nucleosides. Comparison of adherent hRPTC cultures derived from kidneys from different individuals demonstrated that hCNT3 activities varied between cultures. Also, the extent of cellular uptake of fludarabine, an anti-cancer nucleoside drug, and degree of cytotoxicity was reflected in the different hCNT3 activities observed between cultures. These results suggested that hCNT3 plays an important role in fludarabine renal handling and is a determinant of potential renal toxicities. Production of polarized monolayer cultures of hRPTCs on transwell permeable inserts enabled the functional localization of hCNT3 and hENT1 to apical membranes and hENT2 to basolateral membranes. Transepithelial flux studies demonstrated that (i) apical-to-basolateral fluxes of adenosine were mediated by apical hCNT3 and basolateral hENT2, (ii) basolateral-to-apical fluxes of 2′-deoxyadenosine were mediated, in part, by apical hENT1 and basolateral hOATs, and (iii) apical-to-basolateral fluxes of fludarabine, cladribine, and clofarabine were mediated by apical hCNT3. These studies showed that coupling of apical hCNT3 to basolateral hENT2 mediates proximal tubular nucleoside reabsorption, that coupling of basolateral human organic anion transporters (hOATs) to apical hENT1 mediates proximal tubular nucleoside secretion, and that hCNT3 is a key determinant of fludarabine proximal tubular reabsorption and cytoxicity.

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