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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.
31

Novel Approaches to Positively Impact the Early Life Physiology, Endocrinology, and Productivity of Bulls

Harstine, Bo R. January 2016 (has links)
No description available.
32

Estudo do perfil de expressão gênica na distrofia muscular fácio-escápulo-umeral (FSH) / Study of gene expression profile in facioscapulohumeral muscular dystrophy (FSHD)

Arashiro, Patricia 19 March 2009 (has links)
FSH é caracterizada por uma grande variabilidade clínica inter- e intrafamilial. Aproximadamente 10-20% dos pacientes ficam em cadeira de rodas, enquanto que 20-30% dos portadores do alelo com a contração permanecem assintomáticos ou minimamente afetados. Interessantemente, estes casos parecem estar concentrados em determinadas famílias, sugerindo que algum mecanismo deve estar agindo nestes indivíduos, protegendo-os dos efeitos da doença. Para tentar explicar esta variabilidade clínica em FSH, nós comparamos o perfil de expressão gênica a partir do músculo de três membros (afetado, portador assintomático e controle normal) de cinco famílias diferentes através do microarray de expressão e de exons. Nossos resultados sugerem que a expressão dos genes no cromossomo 4q está alterada nos afetados e nos assintomáticos. Interessantemente, as alterações observadas nas amostras dos assintomáticos estão relacionadas aos genes de quemocinas, enquanto que as alterações vistas nas amostras dos afetados estão relacionadas com os genes envolvidos nos processos de acetilação de histonas e da modificação pós-traducional âncora-GPI. Além disto, os pacientes afetados e os assintomáticos compartilham o haplótipo 4qA161 e, desta forma, estes polimorfismos sozinhos não explicam a patogenicidade do alelo com a contração. Nossos resultados corroboram com as observações anteriores de FSH deve ser causada pela desregulação transcricional de vários genes, tanto in cis como in trans, e sugerem alguns fatores potencialmente importantes na patogênese de FSH. O estudo do perfil da expressão gênica dos portadores assintomáticos é uma abordagem nova que está revelando resultados novos e bem interessantes. Entender tal mecanismo é um grande desafio, mas que certamente levará ao desenvolvimento de novas ferramentas para o prognóstico e um possível tratamento. / FSHD is characterized by a great clinical inter and intrafamilial variability. Approximately 10-20% of patients eventually becoming wheelchair-bound while 20-30% with a shortened D4Z4 array, remains asymptomatic or minimally affected. Interestingly, these cases seem to be concentrated in some particular families, suggesting that some mechanism might be acting in these individuals, protecting them form the effects of the disease. In order to try to explain this clinical variability observed in FSHD, we compared the expression profiles of muscle tissue from three members (affected, asymptomatic carrier and normal control) from five unrelated FSHD families through expression and exon microarrays. Our results suggest that the expression of genes on chromosome 4q is altered in affected and asymptomatic individuals. Remarkably, the changes seen in asymptomatic samples are largely in products of genes encoding several chemokines, whereas the changes seen in affected samples are largely in genes governing the synthesis of GPI-linked proteins and histone acetylation. Besides this, the affected patient and related asymptomatic carrier share the 4qA161 haplotype, thus these polymorphisms by themselves do not explain the pathogenicity of the contracted allele. Together, our results support the previous evidences that FSHD may be caused by transcriptional dysregulation of multiple genes, in cis and in trans, and suggest some factors potentially important for FSHD pathogenesis. The study of gene expression profiles from asymptomatic carriers is a novel approach that is revealing new and interesting results. Understanding such mechanisms is a great challenge, but will certainly lead to the development of new tools for prognosis and also for future treatment.
33

Dynamics and regulation of ovarian antral follicular waves in sheep

Duggavathi, Rajesha 22 December 2004
The focus of the present thesis was on ultrasonographic, endocrine and molecular characterization of ovarian antral follicular waves in sheep. Transrectal ultrasonography and computer assisted image analysis were used to determine the feasibility of detecting ovulation and the forming corpus luteum (CL) and to non-invasively monitor CL differentiation and growth. High resolution transrectal ultrasonography and hormone measurements were used to assess changes in numbers of small ovarian antral follicles and their relationships to the emergence of follicular waves in cyclic ewes and to correlate pulsatile secretion of gonadotropins with follicular growth in a wave, during the mid to late-luteal phase of the ovine estrous cycle. A series of experiments were conducted, using treatment with injections of ovine follicle stimulating hormone (oFSH) and measurement of serum concentrations of FSH, in cyclic and anestrous sheep, to investigate the existence of follicular dominance. We also evaluated the characteristics of secretory patterns of FSH that are critical for follicular wave emergence, in anestrous ewes. The possible existence of an endogenous rhythm of FSH secretion, independent of ovarian antral follicular dynamics, was studied in ovariectomized ewes. Finally, ovarian antral follicles at defined stages of growth in a follicular wave (based on transrectal ultrasonographic observations) were collected from separate groups of sheep by ovariectomy, to profile the expression patterns of steroidogenic enzymes (3¦Â-HSD, 17¦Á-OH and aromatase) using immunohistochemistry and gray-scale densitometric analysis. <p> The results of the present studies showed that it is possible to detect ovulation and visualize developing CL as early as 12-24 h after ovulation in the ewe. Changes in echotexture of the CL were closely associated with its morphological and functional characteristics, and we concluded that computer assisted image analysis holds promise for the noninvasive monitoring of CL differentiation and growth. Follicles reaching ovulatory diameter (¡Ý 5 mm) emerged and grew in a wave-like pattern in sheep, but without variation in the number of small follicles (1-3 mm in diameter), as seen in cattle. We concluded that all follicles that are recruited to grow beyond 2-3-mm in diameter, to 4-mm diameter in a wave, succeed in reaching an ovulatory diameter of ¡Ý 5 mm in the ewe. The emergence and growth of ovarian antral follicles in follicular waves, in sheep, do not require changes in LH secretion and may perhaps involve changes in the follicular sensitivity to LH. The largest follicle of a wave, in sheep, appears to have limited effects on other small follicles and on the time of emergence of the next follicular wave. Thus, functional dominance, as is present in cattle, may be absent in sheep. An endogenous rhythm for periodic peaks in serum FSH concentrations that is independent of ovarian follicular dynamics may exist in sheep. The expression patterns of steroidogenic enzymes, in the theca and granulosa compartments of antral follicles growing in each follicular wave in the ewe, paralleled serum estradiol concentrations, with the exception of the concentrations of 3¦Â-HSD in granulosa cells, which increased continuously from follicles 3 mm in diameter to the preovulatory follicle after the LH surge. The largest follicle of any follicular wave, irrespective of the stage of the cycle, would appear to be mature enough to ovulate if a gonadotropin surge is provided.
34

Dynamics and regulation of ovarian antral follicular waves in sheep

Duggavathi, Rajesha 22 December 2004 (has links)
The focus of the present thesis was on ultrasonographic, endocrine and molecular characterization of ovarian antral follicular waves in sheep. Transrectal ultrasonography and computer assisted image analysis were used to determine the feasibility of detecting ovulation and the forming corpus luteum (CL) and to non-invasively monitor CL differentiation and growth. High resolution transrectal ultrasonography and hormone measurements were used to assess changes in numbers of small ovarian antral follicles and their relationships to the emergence of follicular waves in cyclic ewes and to correlate pulsatile secretion of gonadotropins with follicular growth in a wave, during the mid to late-luteal phase of the ovine estrous cycle. A series of experiments were conducted, using treatment with injections of ovine follicle stimulating hormone (oFSH) and measurement of serum concentrations of FSH, in cyclic and anestrous sheep, to investigate the existence of follicular dominance. We also evaluated the characteristics of secretory patterns of FSH that are critical for follicular wave emergence, in anestrous ewes. The possible existence of an endogenous rhythm of FSH secretion, independent of ovarian antral follicular dynamics, was studied in ovariectomized ewes. Finally, ovarian antral follicles at defined stages of growth in a follicular wave (based on transrectal ultrasonographic observations) were collected from separate groups of sheep by ovariectomy, to profile the expression patterns of steroidogenic enzymes (3¦Â-HSD, 17¦Á-OH and aromatase) using immunohistochemistry and gray-scale densitometric analysis. <p> The results of the present studies showed that it is possible to detect ovulation and visualize developing CL as early as 12-24 h after ovulation in the ewe. Changes in echotexture of the CL were closely associated with its morphological and functional characteristics, and we concluded that computer assisted image analysis holds promise for the noninvasive monitoring of CL differentiation and growth. Follicles reaching ovulatory diameter (¡Ý 5 mm) emerged and grew in a wave-like pattern in sheep, but without variation in the number of small follicles (1-3 mm in diameter), as seen in cattle. We concluded that all follicles that are recruited to grow beyond 2-3-mm in diameter, to 4-mm diameter in a wave, succeed in reaching an ovulatory diameter of ¡Ý 5 mm in the ewe. The emergence and growth of ovarian antral follicles in follicular waves, in sheep, do not require changes in LH secretion and may perhaps involve changes in the follicular sensitivity to LH. The largest follicle of a wave, in sheep, appears to have limited effects on other small follicles and on the time of emergence of the next follicular wave. Thus, functional dominance, as is present in cattle, may be absent in sheep. An endogenous rhythm for periodic peaks in serum FSH concentrations that is independent of ovarian follicular dynamics may exist in sheep. The expression patterns of steroidogenic enzymes, in the theca and granulosa compartments of antral follicles growing in each follicular wave in the ewe, paralleled serum estradiol concentrations, with the exception of the concentrations of 3¦Â-HSD in granulosa cells, which increased continuously from follicles 3 mm in diameter to the preovulatory follicle after the LH surge. The largest follicle of any follicular wave, irrespective of the stage of the cycle, would appear to be mature enough to ovulate if a gonadotropin surge is provided.
35

Einfluß des FecB-Gens auf die Follikeldynamik sowie die FSH- und Östradiol 17ß Blutplasmakonzetrationen bei zyklischen und frühgraviden Booroola-Merinofleischschaf-Kreuzungstieren in Abhängigkeit von der Ovulationsrate

Pfeil, Andreas 28 November 2004 (has links) (PDF)
No description available.
36

Reproductive responses of anestrous ewes to the introduction of rams /

Ungerfeld, Rodolfo, January 2003 (has links) (PDF)
Diss. (sammanfattning). Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 6 uppsatser.
37

Effect of nutrition on follicle development and ovulation rate in the ewe /

Viñoles Gil, Carolina, January 2003 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 4 uppsatser.
38

Protocolos de insemina??o artificial em tempo fixo e efici?ncia reprodutiva em vacas e novilhas mesti?as leiteiras / Protocols for fixed time artificial insemination and reproductive efficiency of dairy cows and heifers

Fernandez, Jorge Augusto Santos January 2010 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-11-19T18:46:32Z No. of bitstreams: 2 jorge_augusto_santos_fernandes.pdf: 239160 bytes, checksum: 9bbfbe7abcecc3d5ea2ab2a068a582ee (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-11-19T18:47:05Z (GMT) No. of bitstreams: 2 jorge_augusto_santos_fernandes.pdf: 239160 bytes, checksum: 9bbfbe7abcecc3d5ea2ab2a068a582ee (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Made available in DSpace on 2015-11-19T18:47:06Z (GMT). No. of bitstreams: 2 jorge_augusto_santos_fernandes.pdf: 239160 bytes, checksum: 9bbfbe7abcecc3d5ea2ab2a068a582ee (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Previous issue date: 2010 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Na busca de biot?cnicas economicamente vi?veis para a melhoria da efici?ncia reprodutiva na pecu?ria, objetivou-se com este trabalho avaliar diferentes protocolos de insemina??o artificial em tempo fixo (IATF) em vacas mult?paras e observar o efeito do mesmo protocolo comparando mult?paras e prim?paras observando-se a influ?ncia do horm?nio fol?culo estimulante (FSH-p) na IATF. Os tratamentos utilizados foram TControle, TFSH e TFNOV, que consistiram nos seguintes protocolos: TControle (n=35) - Dia 0, inser??o de dispositivo intravaginal de progesterona e aplica??o de 2 mg de benzoato de estradiol, intramuscular (IM); dia 8, retirada do dispositivo e aplica??o de 0,53 mg de PGF2? e 1 mg de benzoato de estradiol, IM; dia 10, IATF realizada 44 h ap?s a retirada do dispositivo; TFSH (n=36) - similar ao TControle, por?m com aplica??o no dia 8 de 15 mg de FSH-p; TFNOV (n=24)- similar ao TFSH, por?m utilizando-se novilhas. Ao final do trabalho observou-se que houve efeito (P<0,05) para peso vivo (PV) e escore de condi??o corporal (ECC) com os tratamentos. N?o houve efeito para dias p?s-parto (P>0,05). Houve diferen?a (P<0,05) entre as m?dias de peso vivo entre as vacas mult?paras (TControle e TFSH) quando comparadas as novilhas (TFNOV). N?o houve efeito (P>0,05) entre protocolos, PV e ECC no retorno ao estro, na cobertura com o touro e prenhez acumulada. N?o houve efeito (P>0,05) entre os protocolos e retorno ao estro e as taxas de prenhez na IATF, cobertura do touro e acumulada. Mesmo o uso do FSH-p n?o influenciando a efici?ncia reprodutiva, a taxa de prenhez acumulada foi satisfat?ria em ambos tratamentos. Conclui-se a IATF como interessante biot?cnica para o uso na produ??o animal; por?m, ? importante que haja um bom acompanhamento nutricional dos animais, em raz?o da rela??o entre nutri??o e reprodu??o. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Zootecnia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2010. / ABSTRACT In search of biotechnical economically feasible to improve reproductive efficiency in livestock, aimed to evaluate with this work different protocols for TAI in multiparous cows and observe the effect of the same protocol when comparing multiparous and primiparous cows and observing the influence of FSH-p in TAI. The treatments consisted of: TControl (n=35)- Day 0, insertion of intravaginal progesterone device and application of 2 mg estradiol benzoate, intramuscular (IM), Day 8, removed from the device and application of 0.53 mg PGF2? and 1 mg estradiol benzoate, IM; Day 10, TAI performed 44 h after removal of the device; TFSH (n=36)- similar to TControl, but with the application on day 8 of 15 mg of FSH-p; TFNOV (n=24)- similar to TFSH but using heifers. At the end of the work observed that was an interaction (P <0.05) analyzed the effects for BW and BCS with treatments. There was no effect for days postpartum (P> 0.05). There were difference (P <0.05) between the mean body weight among the cows (and TFSH TControl) compared with heifers (TFNOV). There was no effect (P> 0.05) between protocols, body weight and body condition on return to estrus in coverage with the bull and accumulated pregnancy. There was no effect (P> 0.05) between the protocols and return to estrus and pregnancy rates of TAI, the bull and the accumulated coverage. Even the use of FSH-p does not influence the reproductive efficiency, the cumulative pregnancy rate was found satisfactory in both treatments, thus concludes the TAI as interesting biotech for use in animal production, but it is important to have a good nutritional monitoring of animals, because the relationship between nutrition and reproduction.
39

Caracterização físico-química da foliculotrofina humana (hFSH) recombinante e de suas subunidades, por cromatografia líquida de alta eficiência (HPLC) em fase reversa: comparação com a preparação de referência de hFSH de origem hipofisária do 'National Hormone and Pituitary Program' dos EUA

LOUREIRO, RENAN F. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:52:13Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:55Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
40

Analise de luteotrofina humana e de gonadotrofina corionica humana, recombinante e natural, por cromatografia liquida de alta eficiencia em fase reversa / Analysis of recombinant and native human lutropin and human chorionic gonadotropin by reversed-phase high performance liquid chromatography

ALMEIDA, BEATRIZ E. de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:26:59Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:03:49Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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