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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.
11

Affinity chromatographic purification of recombinant human growth hormone

Balci, Oguz 01 February 2008 (has links) (PDF)
The purpose of the study is to purify human growth hormone from the fermentation broth by affinity chromatography. For this purpose, human growth hormone specific oligonucleotide aptamers are selected among an aptamer library / selected oligonucleotides were synthesized and used as ligands. Effect of pH on ligand-human growth hormone complex formation was investigated and the highest complex formation was obtained at pH= 7.0. Human growth hormone is separated from the fermentation broth with 99.8% purity and 41% overall yield. The equilibrium data obtained was described by Langmuir type isotherm where saturation constant (q0) and affinity constant (K) are calculated as 0.338 mg hGH/&micro / mol aptamer and 0.059 mg hGH/ml, respectively. Further, equilibrium data obtained using aptamer affinity column was described by Langmuir type isotherm where saturation constant (q0) and affinity constant (K) are 0.027 mg hGH/&micro / mol aptamer and 1.543 mg hGH/ml, respectively. It is possible that, selected aptamer can be used for purification of bulk amounts of recombinant human growth hormone by using aptamer affinity chromatography.
12

Utiliza??o do horm?nio de crescimento humano (GH) em procedimentos de preserva??o ?ssea alveolar p?s-exodontia

Zanettini, Leonardo Matos Santolim 10 January 2018 (has links)
Submitted by PPG Odontologia (odontologia-pg@pucrs.br) on 2018-03-26T12:53:16Z No. of bitstreams: 1 LEONARDO_MATOS_SANTOLIM_ZANETTINI_DIS.pdf: 2920184 bytes, checksum: f65b15c1056e1a9173b56c1789377ba8 (MD5) / Approved for entry into archive by Tatiana Lopes (tatiana.lopes@pucrs.br) on 2018-04-06T16:34:38Z (GMT) No. of bitstreams: 1 LEONARDO_MATOS_SANTOLIM_ZANETTINI_DIS.pdf: 2920184 bytes, checksum: f65b15c1056e1a9173b56c1789377ba8 (MD5) / Made available in DSpace on 2018-05-18T14:04:05Z (GMT). No. of bitstreams: 1 LEONARDO_MATOS_SANTOLIM_ZANETTINI_DIS.pdf: 2920184 bytes, checksum: f65b15c1056e1a9173b56c1789377ba8 (MD5) Previous issue date: 2018-01-10 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / . / Recombinant Human Growth Hormone (RhGh) has been studied in cases of dental implants, TMJ pathologies and bone fractures. It is able to stimulate bone growth in a dose-dependent manner by direct stimulation of chondrocytes. It stimulates proliferation and differentiation of chondroprogenitor cells, also acts directly on osteoblasts, increasing rates of remodeling and bone formation. In this review of the literature and case report, RhGh will be used in alveolar ridge preservation procedures, with the purpose of evaluating the benefits of this technique in maintaining the postextraction bone site viable, aiming a future rehabilitation with dental implants and prostheses.
13

Human growth hormone receptor : developmental changes and gene regulation

Kenth, Gurvinder. January 2007 (has links)
No description available.
14

Process development for downstream processing of human growth hormone and its antagonist

Zheng, Yizhou January 1994 (has links)
No description available.
15

Purification techniques for human growth hormone (hGH) and an hGH antagonist

Gu, Yesong January 1995 (has links)
No description available.
16

Production of human growth hormone antagonist (hGHG120R) in Chinese hamster ovary cells

Haldankar, Raj January 1997 (has links)
No description available.
17

The Delivery of Human Growth Hormone to Dogs Using Microencapsulated Non-Autologous Cells

Peirone, Michael 09 1900 (has links)
Many of the presently approved somatic gene therapy protocols involve reimplantation of genetically engineered autologous cells into a patient. A potentially more cost-effective approach to the delivery of therapeutic gene products is the use of a universal recombinant cell line that can be implanted into a number of patients with the same product requirements. Enclosure of these non-autologous cells inside a permselective microcapsule membrane would permit the diffusion of the recombinant product but prevent entry of the host’s immune mediators. The clinical efficacy of this approach has been demonstrated by the implantation of recombinant fibroblasts and myoblasts to correct mutant phenotypes in murine models of diseases such as dwarfism (Al-Hendy et al., 1995) and lysosomal storage disease (Bastedo, 1994). In the first part of this thesis, a new microcapsule type was created that incorporated a combination of traits from both alginate-poly-L-lysine-alginate and barium-alginate microcapsules. The new, barium-poly-L-lysine-alginate microcapsule was cross-linked with BaCl2 and received a poly-L-lysine, and a second alginate coat. The three different types of microcapsules were compared with respect to encapsulated cell viability, proliferation and secretion in vitro. Results of these analyses demonstrated that cells inside alginate-poly-L-lysinealginate microcapsules had higher viability and a greater proliferation rate than did cells inside either barium-alginate or barium-poly-L-lysine alginate microcapsules. However, secretion from the alginate-poly-L-lysine alginate microcapsules was lower than from either of the barium-alginate types, and the two types of barium-alginate microcapsules, formulated with a higher alginate concentration, were more resistant to well-defined fluid shearing forces, than was the calcium alginate microcapsule. No significant difference in any of the parameters measured was observed between the barium-alginate and bariumpoly-L-lysine alginate microcapsule types. In the second part of this thesis the three different types of microcapsules, each containing canine MDCK cells secreting ~20 ng/106 cells/hr of human growth hormone (hGH) were implanted into the peritoneal cavities of a large animal model. The microencapsulated cells were able to deliver recombinant human growth hormone to the circulation of dogs at levels nearly 100 % higher than human physiological levels. In contrast, implantation of unencapsulated recombinant cells resulted only in short-term delivery of hGH to the dogs. The level of titre of anti-hGH antibodies was monitored in the experimental and control animals, and its increase was determined to be associated with the disappearance of the human growth hormone from the circulation of the dogs. The BaCl2 cross-linked capsules with the higher alginate concentration lasted longer in vivo, confirming their superior mechanical integrity relative to the alginate-poly-L-lysine alginate type. The presence of the microcapsules in the peritoneum of the dogs was associated with localized inflammation of the omentum, and mild lymphadenitis. This pathology, combined with varying degrees of fibrotic overgrowth of the microcapsules with increasing time in vivo, suggests that modifications must be made in order to improve the biocompatibility of alginate microcapsules. In conclusion, modifications of alginate microcapsules, such as the cross-linking with barium cations, the use of higher alginate concentrations and lamination with polyL-lysine alginate have contributed to the mechanical stability of the capsules and permitted the long-term delivery of recombinant gene products using non-autologous cells. This study has highlighted some of the issues to be addressed during pre-clinical studies in large animal models, in order to determine the efficacy of this new technology for humans. / Thesis / Master of Science (MS)
18

CIS/SOCS Proteins in Growth Hormone Action: A Dissertation

Du, Ling 01 October 2000 (has links)
CIS/SOCS (cytokine-inducible SH2 protein/suppressor of cytokine signaling) are a family of proteins that are thought to act as negative regulators of signaling by erythropoetin, interleukin-6 and other cytokines whose receptors are related to the growth hormone receptor (GHR), and like growth hormone (GH), signal through the JAK/STAT pathway. We examined the possibility that CIS/SOCS proteins may also be involved in GH signaling, in particular, in termination of the transient insulin-like effects of GH. mRNAs for CIS, SOCS3, and to a lesser extent SOCS1 were detectable by Northern blot analysis of rat adipocyte total RNA, and the expression of CIS and SOCS3 was markedly increased 30 min after incubation with 500 ng/ml hGH. Both CIS and SOCS3 were detected in adipocyte extracts by immunoprecipitation and immunoblotting with their corresponding antisera. GH stimulated the tyrosine phosphorylation of a 120 kDa protein (p120) that was co-precipitated from adipocyte extracts along with αCIS and detected in Western blots with phospho-tyrosine antibodies. However, no tyrosine phosphorylated proteins in these cell extracts were immunoprecipitated with antibodies to CIS3/SOCS3. p120 was later identified as the GHR based on the observations that two GHR antibodies recognized p120 in scale-up experiments and that p120 and the GHR share several characteristics, including their molecular weights, tyrosine phosphorylation upon GH stimulation, interaction with CIS, similar extent of glycosylation as judged by electrophoretic mobility shift after Endo F digestion, comparable mobility shifts upon thrombin digestion, and N-terminal histidine-tagging. The findings, however, do not rule out the possibility that there might be other tyrosine phosphorylated 120 kDa protein(s) that interact with CIS and contribute to the p120 signal, as well as the GHR. Further studies of the association of CIS with the GHR revealed that CIS might selectively interact with multiply tyrosine phosphorylated forms of the GHR, and these tyrosines are likely located near the carboxyl end of the GHR. Overexpression of CIS partially inhibited GH-induced STAT5 phosphorylation in CHO cells. Studies in freshly isolated and GH-deprived (sensitive) adipocytes revealed that the abundance of CIS does not correlate with the termination of the insulin-like effects of GH or the emergence of refractoriness. Neither the association of CIS with the GHR nor the tyrosine phosphorylation status of the GHR, JAK2 and STAT5 appear responsible for refractoriness in adipocytes. These data imply that some negative regulators other than CIS might contribute to the termination of GH-induced insulin-like effects in adipocytes.
19

Desenvolvimento do processo de cultivo de Escherichia coli RR1. / Escherichia coli RR1 culture process development.

Rossi, Marcelo 29 November 2001 (has links)
No presente trabalho, cultivou-se o microrganismo Escherichia coli RR1, contendo o vetor que carrega o gene estrutural para a síntese do hormônio de crescimento humano (hGH) (baseado no promotor pL e pR do fago l sob controle do repressor termosensível cI857) em processos descontínuo e descontínuo-alimentado realizados em biorreatores com capacidade útil de 2 e 4 L. Tal cepa é auxotrófica com relação aos aminoácidos l-leucina e l-prolina e à tiamina (vitamina B1). Nos cultivos descontínuos com concentrações menores de extrato de levedura e bactotriptona em relação ao meio denominado basal, a concentração celular foi baixa, atingindo 2,4 g.L-1, com fator de conversão glicose à células de 0,25 g.g-1. Em cultivos descontínuos com aumento (em relação ao meio basal) da concentração de extrato de levedura e de bactotriptona e com adição de l-prolina, a concentração celular alcançou valores da ordem de 5,9 g.L-1 e fator de conversão glicose à células de 0,48 g.g-1, simultaneamente à maior formação de acetato (2,5 g.L-1), este último prejudicial ao processo. Contudo, este resultado de crescimento celular não se repetiu devido a mudança do lote de células utilizado entre o primeiro e o segundo conjunto de ensaios. Os cultivos descontínuos-alimentados foram realizados com diferentes formas de alimentação bem como diferentes composições de solução de alimentação. Uma alimentação contínua com velocidade exponencial e composição semelhante à do meio, pareceu ser a mais favorável, levando à concentração celular final de 9,2 g.L-1 e fator de conversão glicose a células, na fase descontínua-alimentada, de 0,36 g.g-1. Os ensaios com indução térmica não foram eficientes provavelmente devido à problemas na detecção das concentração de glicose existente no instante inicial da ativação da síntese do hGH. Esta glicose presente pode ter prejudicado a formação do hGH por conseqüência do processo fermentativo causado pelo aumento da temperatura e pela presença de elevada concentração de nutrientes complexos. O meio de cultivo utilizado possivelmente não supriu as necessidades metabólicas da célula para a síntese do hormônio de crescimento humano e em nenhum dos cultivos com indução térmica houve a produção de hGH. / In the present work, the host Escherichia coli RR1, having the vector with the structural gene for human growth hormone (hGH) synthesis, based on pL or pR promoters from bacteriophage l under the control of the thermosensitive repressor cI857, was cultivated in batch and fed-batch cultures in bioreactors with working volumes of 2 and 4 L. This host has amino acids (l-leucine and l-proline) and thiamine (Vitamin B1) auxotrophy. Batch cultures under low yeast extract and bacto-tryptone concentrations (relative to the basal medium) resulted in a low biomass yield (2.4 g.L-1) and cell yield on glucose (0.25 g.g-1). Increasing these concentrations and adding l-proline to the medium led to higher biomass formation (5.9 g.L-1), cell yield on glucose (0.48 g.g-1) and acetate high levels (2.5 g.L-1), which were harmful to the process. However, these results of cellular growth were not reproducible due to different cell stocks applied. The fed-batch cultures were performed under different feeding strategies and different nutrients concentrations of the feeding solution. A continuous exponential feeding rate with growth medium-like composition seemed to be the most favorable, reaching final cellular concentration of 9.2 g.L-1 and yield on glucose on fed-batch mode of 0.36 g.g-1. The heat-shock runs were not efficient probably due to problems in detection of glucose concentration existing on initial instant of hGH activation synthesis. Glucose interferes with the hGH synthesis because the fermentation caused by temperature shift and presence of high complex nutrients concentration. The culture medium used, probably was not able to supply cell metabolic needs for the human growth hormone synthesis and in no other temperature-induced experiment the hGH production was observed.
20

Papel da leptina no crescimento sem GH de crianças e adolescentes portadores de craniofaringioma / Leptin role in the metabolism of children and adolescents with craniopharyngioma

Baságlia, Glaucimar Martins Michetti 11 July 2007 (has links)
O craniofaringioma (CF) é o tumor das regiões selar e supra-selar mais comum na infância, que cursa com deficiências hipofisárias, principalmente do hormônio de crescimento (GH). As crianças afetadas apresentam redução da velocidade de crescimento (VC) e baixa estatura, mas após a ressecção do tumor, há relatos de pacientes com crescimento normal ou até aumentado mesmo deficientes em GH (DGH). Os mecanismos deste evento não são claros, mas há associações com o ganho de peso. Recentemente foram descritas relações diretas entre a leptina, o GH e o índice de massa corpórea (IMC). Com os objetivos de estabelecer correlações entre a leptina e a velocidade de crescimento (VC) e com o IMC, de correlacionar a leptina e o IGF-I com GH, e de verificar se o GH exógeno modifica o perfil de leptina nos portadores de CF e DGH, foram estudados 15 pacientes portadores de CF, sendo sete meninos e oito meninas, menores de 18 anos, deficientes em GH e impúberes. Os pacientes foram divididos em dois grupos (1 e 2) quanto à reposição com GH em tratados e não-tratados, respectivamente, e foram avaliados quanto a VC, IMC, leptinemia, insulinemia, lipidograma e IGF-I nos dois primeiros anos após a primeira cirurgia. Foi estabelecida correlação entre o IMC e a leptinemia e, para os pacientes do grupo 2, foram estabelecidas correlações entre a VC e o IGF-I, a insulinemia, o índice HOMA e a leptinemia. Após a primeira neurocirurgia, 13 pacientes cursaram com hipocortisolismo, 11 com diabetes insipidus definitivo, 12 com hipotiroidismo e todos com deficiência de GH. As medianas dos valores de Z-escore das velocidades de crescimento (Z-VC) no primeiro e segundo anos, respectivamente ,foram: no grupo 1, 0,61 e -1,86; e no grupo 2, 0,85 e 0,94. Os valores do Z-IMC final do grupo 1 variaram de -0,24 a 2,74, e no grupo 2, de -0,12 a 2,88. Não houve correlação entre o Z-IMC e o Z-VC. Os pacientes apresentaram hiperleptinemia (MZ-leptina = 10,58 e DP = 14,08), com correlação positiva entre os valores de leptina e o Z-IMC final (P = 0,0095). Não houve correlação entre os valores da leptina e o Z-VC. A correlação entre a insulina e o Z-IMC foi significante apenas no grupo 1 (P = 0,001). A insulina não se correlacionou com a VC no grupo 2. A correlação entre o IGF-I e a VC foi positiva apenas no primeiro ano (P = 0,007). Não houve diferença estatisticamente significante entre a leptina e o IGF-I, nos pacientes do grupo 2. Concluímos que houve correlação positiva entre os valores de leptina e o IMC nos pacientes portadores de CF e DGH; não houve correlação entre a leptina e a VC; não houve correlação positiva entre o IGF I e a leptina dos pacientes com CF e DGH não-tratados com hGH e não houve diferença estatística dos valores de leptina entre os grupos tratados e não-tratados. / Craniopharyngioma (CF) is a tumor of the sellar and suprasellar regions, more commonly found in children, its course being associated with hypophyseal hormones deficiency, especially growth hormone (GHD). Affected children have reduced growth rates (GR) and short stature. However, after tumor resection, patients have been reported to exhibit normal or increased growth rates, even in the presence of GH deficiency. The underlying mechanisms to this phenomenon are not clear, yet they are known to be associated with weight gain. Recently, a direct relation between leptin, GH and the body mass index (BMI) has been reported. With the objective of establishing correlations between leptin, growth rate (GR) and BMI; correlate leptin and IGF-I with GH, and verify if exogenous GH modifies the leptin profile in patients with CF and GHD, 15 GH-deficient and impuberal patients with CF, 7 boys and 8 girls, under the age of 18, were studied. According to the use of GH replacement therapy, patients were divided into 2 groups (1 and 2), respectively treated and non treated, and were evaluated for GR and BMI, leptinemia, insulinemia, lipidogram and IGF-I during the first 2 years after the first surgery. Correlation was established between BMI and leptinemia and, for the patients in group 2, correlations were established between GR and IGF-I, insulinemia, the HOMA index and leptinemia. After the first neurosurgery, 13 patients evolved with hypocortisolism, 11 with established diabetes insipidus, 12 with hypothyroidism and all patients were GH-deficient. Mean growth rate Z-score values (Z-GR) in the 1st and 2nd year, respectively, were: group 1: 0.61 and 1.86 and group 2: 0.85 and 0.94. Final Z-BMI values ranged from -0.24 to 2.74 for group 1 and from -0.12 to 2.88 for group 2. There was no correlation between Z-BMI and Z-GR. The patients showed hyperleptinemia (MZ-leptin = 10.58; SD = 14.08), with positive correlation between leptin values and the final Z-BMI (P=0.0095). There was no correlation between leptin values and Z-GR. The correlation between insulin and Z-BMI was only significant in group 1 (P = 0.001). Insulin did not correlate with GR in group 2. The correlation between IGF-I and GR was only positive in the 1st year (P = 0.007). There was t correlation between leptin and the IGF I in group 2. We conclude that there was a positive correlation between leptin values and the IMC in patients with CF and DGH; there was no correlation between leptin and GR; there was no positive correlation between IGF I and leptin in patients with CF and GHD not treated with hGH, and there was no statistical difference in leptin values between treated and non-treated groups.

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