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Reproductive and Growth Responses of the Fathead Minnow (Pimephales Promelas) and Japanese Medaka (Oryzias Latipes) to the Synthetic Progestin, NorethindronePaulos, Peter M. 05 1900 (has links)
A commonly prescribed contraceptive, the synthetic progestin norethindrone (NET) inhibits ovulation in humans. However, ecotoxicological data are lacking. Preliminary tests produced an LC50 for NET of > 1.0 mg/L (96-hour, fathead minnow (FHM) and medaka) and a NOEC of 242.0 µg/L, a LOEC of 485.0 µg/L (7-day, growth for FHM and medaka). Reproductive testing revealed a LOEC for fecundity of 24.1 ng/L (21 days, medaka). Further testing confirmed the LOEC of 24.1 ng/L while defining a NOEC of 4.7 ng/L (28 days, medaka). Effect of NET in medaka life-cycle exposure at concentrations exceeding 4.7 ng/L was evident. Few females were present in the 24.7 ng/L exposure concentration, with none in the 104.6 ng/L. Egg production was significantly reduced at concentrations exceeding 4.7 ng/L. Additionally, weight, condition factor and somatic indices were significantly different in males exposed to concentrations exceeding 4.7 ng/L. For fecundity and sexual differentiation; the NOEC was 4.7 ng/L, the LOEC 24.6 ng/L; growth and somatic indices, the NOEC was more appropriately 0.9 ng/L, with effect evident at 4.7 ng/L. Sexual differentiation of the F1 population was similar to the F0. A defining result of this test was development of exceptionally large ovaries in NET- exposed female medaka, perhaps indicative of a threshold limit for exposure in these fish. Results of FHM life-cycle testing were similar, establishing a NOEC for fecundity of 0.9 ng/L, a LOEC of 4.8 ng/L. NET's inhibitory effect on gonadal development was obvious; GSI NOEC for males, 4.8 ng/L, and histological examination confirmed the presence of intersex development at elevated concentrations. Normal physical development and growth were impaired, generally at concentrations exceeding 24.1 ng/L. At exposure concentrations exceeding 4.8 ng/L, external sexual confirmation of fish was difficult; LOEC for finspot development in females, 4.8 ng/L. Sexual determination of the 97.1 ng/L exposure group was impossible; externally, all fish appeared male and internal examination revealed no gonadal development.
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An in vitro investigation of the anti-inflammatory and immunosuppressive effects of the synthetic contraceptives medroxyprogesterone acetate (MPA) and norethisterone acetate (NET-A) /Kriek, W. J. January 2005 (has links)
Thesis (MScMed)--University of Stellenbosch, 2005. / Bibliography. Also available via the Internet.
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Comparative study of the molecular mechanism of action of the synthetic progestins, Medroxyprogesterone acetate and Norethisterone acetateAfricander, Donita Jean 03 1900 (has links)
Thesis (PhD (Biochemistry))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: Medroxyprogesterone acetate (MPA) and norethisterone (NET) and its
derivatives (norethisterone enanthate (NET-EN); norethisterone acetate (NETA)),
are used by millions of women as contraceptives and in hormone
replacement therapy (HRT). Although both progestins are widely used, very
little is known about their mechanism of action at the molecular level. In this
thesis, the differential regulation of gene expression and molecular
mechanism of action via different steroid receptors by these synthetic
progestons, as compared to progesterone (Prog) was investigated in human
cell lines. In the first part of the study, the effect of Prog, MPA and NET-A on
the expression of endogenous cytokine genes was investigated in two
epithelial cell lines of the human female genital tract, Ect1/E6E7 (an
ectocervical cell line) and Vk2/E6E7 (a vaginal cell line). Quantitative realtime
RT-PCR (QPCR) showed ligand-specific and cell-specific regulation of the
interleukin (IL)-6, IL-8 and RANTES (Regulated-upon-Activation, Normal T cell
Expressed and Secreted) genes with Prog, MPA and NET-A. Moreover, the
repression of the TNF -induced RANTES gene by MPA in the Ect1/E6E7 cell
line was found to be mediated by the androgen receptor (AR). The second
part of the study focused on elucidating the androgenic activities of these two
progestins, in comparison to Prog. Competitive binding in whole cells revealed
that Prog, MPA and NET-A have a similar binding affinity for the hAR as the
natural androgen dihydrotestosterone (DHT). Both transactivation and
transrepression transcriptional assays demonstrate that, unlike Prog, MPA
and NET-A are efficacious AR agonists, with activities comparable to DHT.
Using a mammalian two-hydrid assay, it was shown that MPA and NET-A
exert their androgenic actions by different mechanisms. NET-A, like DHT and
other well-characterised androgens, induces the ligand-dependent interaction
between the NH2- and COOH-terminal domains (N/C-interaction) of the AR
independent of promoter-context, while MPA does this in a promoterdependent
manner. In the third part of this study, competitive binding revealed
that MPA and NET-A have a similar binding affinity to each other, but about a
100-fold lower affinity than Prog for the human mineralocorticoid receptor
(hMR), while RU486 has an even lower affinity for the hMR. Promoter-reporter
assays showed that MPA, NET-A and RU486 are all antagonists of the hMR,
but unlike Prog, they have weak antagonistic activity. However, on the
endogenous MR-regulated Orm-1 (a-glycolytic protein or orosomucoid-1)
gene expressed in a rat cardiomyocyte cell line, NET-A and RU486, but not
MPA, has similar antagonistic activity as Prog. This study is the first to show
that, NET-A and RU486, but not MPA, can dissociate between
transrepression and transactivation via the hMR. Taken together, these
results show that natural Prog and the synthetic progestins, MPA and NET-A
display differential promoter-, cell- and receptor-specific effects on gene
expression. Furthermore they may have important implications for
cervicovaginal immune function, cardiovascular and other physiological
functions. / AFRIKAANSE OPSOMMING: Medroksieprogesteroon asetaat (MPA), noretisteroon (NET) en derivate
daarvan (noretisteroon enantaat (NET-EN); noretisteroon asetaat (NET-A),
word deur miljoene vroue gebruik as voorbehoedmiddels en vir hormoon
vervangingsterapie (HVT). Tenspyte daarvan dat beide hierdie progestiene
algemeen gebruik word, is min bekend oor hulle meganisme van werking op
molekulêre vlak. In hierdie proefskrif word die differensiële regulering van
geenuitdrukking asook die molekulêre meganisme van werking deur middel
van steroïedreseptore van beide hierdie sintetiese progestiene, ondersoek, en
vergelyk met progesteroon (Prog), in menslike sellyne. In die eerste deel van
die studie is die effek van Prog, MPA en NET-A op die uitdrukking van
endogene sitokinien gene ondersoek in twee epiteel sellyne van die menslike
vroulike geslagskanaal, Ect1/E6E7 (‘n ektoservikale sellyn) en Vk2/E6E7 (‘n
vaginale sellyn). Kwantitatiewe intydse RT-PKR het ligand-spesifieke en selspesifieke
regulering van interleukien (IL)-6, IL-8 en RANTES (Regulering-na-
Aktivering, Normale T-sel Uitgedrukte en Afgeskei) gene getoon met Prog,
MPA en NET-A. Verder is gevind dat die onderdrukking van die TNF- -
geïnduseerde RANTES geen deur MPA in die Ect1/E6E7 sellyn bemiddel
word deur die androgeen reseptor (AR). Die tweede deel van die studie het
gefokus op die toeligting van die androgeniese aktiwiteit van die twee
progestiene in vergelyking met Prog. Kompeterende binding in volselle het
getoon dat Prog, MPA en NET-A ‘n soortelyke bindings affiniteit vir die
menslike AR as die natuurlike androgeen dehidrotestosteroon (DHT) vir die
menslike AR het. Beide transaktiverings en transonderdrukkings
transkripsionele analieses toon dat, anders as Prog, MPA en NET-A
effektiewe AR agoniste is met aktiwiteite wat vergelykbaar is met die van
DHT. Deur die gebruik van ‘n soogdier twee-hibried toets, kon gewys word dat
MPA en NET-A hul androgeniese effekte uitoefen deur verskillende
meganismes. NET-A, soos DHT en ander goed gekarakteriseerde androgene,
induseer die ligand-afhanklike interaksie tussen die NH2- en COOH-terminale
domeine (N/C-interaksie) van die AR, onafhanklik van die promoter-konteks.
MPA, aan die ander kant, doen dit op ‘n promoter-afhanklike manier. In die
derde deel van die studie het kompeterende binding getoon dat MPA en NETA
soortelyke relatiewe bindings affiniteite vir die menslike mineralokortikoïed
reseptor (hMR) het, maar dat hierdie affiniteit ongeveer 100-voud laer is as
die van Prog en dat die affiniteit van RU486 vir hMR selfs nog laer is.
Promoter-rapporteerder toetse het getoon dat MPA, NET-A en RU486 almal
antagoniste van die hMR is, maar anders as Prog, is hierdie ‘n swak
antagonistiese aktiwiteit. Nietemin, op die endogene MR-gereguleerde Orm-1
( -glikolitiese proteïen of orosomukoïed-1) geen, uitgedruk in ‘n rot
kardiomiosiet sellyn, het NET-A en RU486, maar nie MPA nie, ‘n soortgelyke
antagonistiese aktiwiteit as Prog. Hierdie studie is die eerste om te wys dat
NET-A en RU486, maar nie MPA nie, kan onderskei tussen transrepressie en
transaktivering deur middel van die hMR. Samevattend toon die resultate dat
natuurlike Prog en die sintetiese progestiene, MPA en NET-A, ‘n differentiële
promoter-, sel- en reseptor-spesifieke effek op geenuitdrukking het. Verder
mag die resultate belangrike implikasies vir servikovaginale immuunfunksie,
asook kardiovaskulêre en ander fisiologiese funksies, inhou.
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Effects of gonadal steroids on galanin and other neuropeptides in the rat brain /Rugarn, Olof, January 1900 (has links) (PDF)
Diss. Linköping : Univ., 2001.
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An in vitro investigation of the anti-inflammatory and immunosuppressive effects of the synthetic contraceptives medroxyprogesterone acetate (MPA) and norethisterone acetate (NET-A)Kriek, W. J. 03 1900 (has links)
Thesis (MScMedSc (Pathology. Medical Microbiology))--University of Stellenbosch, 2005. / The aim of this study was to investigate the anti-inflammatory and
immunosuppressive effects of the synthetic progestins, MPA and NET-A on human
cells in vitro. These injectable contraceptives are used extensively throughout the
world, including Africa. The potential of these two synthetic hormones to have
certain immunosuppressive and GC properties have previously been shown.
Therefore, it was of concern to us to investigate whether these two hormones could
possibly demonstrate any of these GC-like properties at contraceptive doses. This
was achieved by determining the effects of these two synthetic hormones in vitro on
certain immunologic parameters.
Chapter 1 is a literature review on MPA, NET and GCs. This chapter starts with a
short introduction that sets the scene. The mode of action, effectiveness, sideeffects
as well as previously reported relevant data on both MPA and NET-A is
portrayed in this review. Research on the known GC, Dex, is also included in the
section dealing with GCs, because this synthetic hormone was used as a
comparative GC in all our experiments. This chapter soon makes the reader realize
how much evidence exists that indicate the possible immunosuppressive effects
these two contraceptive hormones, in particular MPA, could have.
The possible anti-inflammatory or pro-inflammatory effects of MPA and NET-A are
investigated in Chapter 2. This was done in vitro by measuring the effects of these
two synthetic hormones on the inflammatory markers, IL-6 and TNFα, by means of ELISA. In this chapter we demonstrate that MPA, even at contraceptive doses,
exhibits significant anti-inflammatory properties on both cytokines tested, while NETA
displayed considerably less anti-inflammatory tendencies. In its true antiinflammatory
manner, we found that Dex significantly inhibited the release of both
inflammatory markers from human monocytes.
In Chapter 3, we investigated the effects of MPA and NET-A on the activation of
human lymphocytes. This was achieved by flow cytometric measurement of the
expression of the activation membrane marker CD69 by CD4 and CD8 T cells. Here
we discovered that MPA had a very significant inhibitory effect on the activation of
both CD4+ and CD8+ T cells, while NET-A only significantly inhibited the activation of
CD8+ T cells. In addition, we found that the inhibition of CD4+ and CD8+ T cell
activation by MPA was more or less the same as the known GC, Dex, and in some
cases even more potent.
Chapter 4 consists of an investigation of the effects of MPA and NET-A on the
cytokines belonging to TH1 and TH2 subsets of CD4 T cells. This was achieved by
determining whether MPA and/or NET-A targeted specific subsets of T helper cells
by measuring the distinct regulatory cytokines, IFNγ and IL-4. The mechanism and
role of the T helper subsets are discussed in the introduction of this chapter. Our
results were portrayed as a ratio of TH2: TH1 on which the statistical analysis was
done. In addition to the analysis done on the ratio, we analyzed the helper subsets
separately in order to determine which subset(s) were influenced. The results of this chapter showed that neither MPA nor NET-A significantly affected either one of the
helper subsets, while Dex significantly decreased this ratio.
After our observed effects of MPA and NET-A on CD8 T cells, it became of interest
in Chapter 5 to investigate the effects of these two synthetic hormones on the CD8 T
cell-specific chemokine, RANTES. This was achieved by measuring the effects
MPA and NET-A had on RANTES production in vitro by means of ELISA.
Surprisingly, we discovered in this chapter that MPA and NET-A enhanced RANTES
production before and after activation of CD8 T cells. We also found that Dex had
the same effect on RANTES production, but to a lesser degree.
Finally, a general conclusion depicting the significance and implications of our
results as well as possible future research that is required is presented in Chapter 6.
It was of great importance to discuss and interpret the magnitude of data generated
out of all our experiments to the utmost of our capabilities. We found that MPA,
even at contraceptive doses, displayed significant immunosuppressive as well as
anti-inflammatory properties. NET-A, on the other hand, demonstrated weaker
immunosuppressive properties in our research and no significant anti-inflammatory
properties. These findings could have clinical implications in females being treated
with these synthetic contraceptives. We also demonstrated significant variation
found amongst genders in response to MPA, NET-A and Dex.
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"Avaliação do tratamento hormonal e/ou intervencionista por punção nos tumores císticos de ovários" / Evaluation of hormonal treatment and/or intervention through aspiration of ovarian cystic tumorsChnee, Lúcia Helena 06 September 2006 (has links)
Objetivo: O objetivo deste estudo foi avaliar em mulheres com tumores císticos de ovário, a proporção que, somente com o tratamento clínico e/ou punção, não necessitaram de cirurgia; a influência da medicação e das doenças associadas na indicação de cirurgia e se a punção reduziu significativamente o tamanho dos cistos. Casuística e métodos: Selecionaram-se 71 mulheres com idade entre 19 e 70 anos de idade, portadoras de tumores císticos de ovário maior que 5 cm, com características de benignidade ao ultra-som transvaginal com Doppler colorido e pulsado e com perfil endócrino e marcadores séricos tumorais normais. Foram divididas em cinco grupos: 1) Grupo A: 15 mulheres que fizeram uso de acetato de noretisterona; 2) Grupo B: 13 mulheres que fizeram uso de acetato de medroxiprogesterona; 3) Grupo C: 14 mulheres que utilizaram contraceptivo oral; 4) Grupo D: 15 mulheres que foram tratadas com análogo de GnRH e 5) Grupo E: 14 mulheres que não fizeram uso de medicação. Todos os grupos foram acompanhados por um ano. No final do primeiro trimestre, se o cisto persistiu, foi realizada a punção. No final do segundo trimestre, se houve recidiva do cisto, foi indicada cirurgia. As pacientes tiveram alta após um ano de acompanhamento com o tratamento do cisto concluído. Resultados: Não houve diferenças significantes entre os cinco grupos. Constatou-se que a condição de uso de medicação para doença associada teve influência significativa no resultado dos tratamentos. Verificou-se que a redução do tamanho do cisto com a punção foi efetiva após 9 meses de acompanhamento. Observou-se que 7% das mulheres tiveram indicação direta para cirurgia sem a punção, portanto, a proporção de recidiva da punção foi de 19,3% enquanto a porcentagem de mulheres que não fizeram a cirurgia foi de 73,2%. Conclusão: A proporção de mulheres que responderam adequadamente somente com o tratamento clínico e/ou a punção, não necessitando pois de cirurgia foi de 73,2%. A influência da medicação/ doença associada no tratamento não cirúrgico foi significativa. A redução do tamanho dos cistos benignos em função do tratamento instituído incluindo a punção foi significativa, a qual foi observada após 9 meses de tratamento. / Objectives: To evaluate the rate of women with ovarian cystic tumors submitted to diferent regimens of hormonal treatment and/or aspiration that didnt need surgery. To access the effectiveness of ovarian cyst aspiration guided by ultrasonography (USG) and to study the influence of medication and associated diseases in the need for surgery. Patients and Methods: Seventy one (71) women, in an age range from 19 to 70 years, diagnosed with ovarian cysts larger than 5 cm in length, with benign aspect, examined using an ultrasonographic transvaginal probe and color Doppler. All the women have been submitted to measurements of ser um tumor markers and hormonal levels. They were grouped in five different categories: 1) Group A: 15 women treated with noretisterone acetate; 2) Group B: 13 subjects treated with medrooxiprogesterone acetate; 3) Group C: 14 patients treated with combined oral contraceptive; 4) Group D: 15 women treated with GnRH analog, and 5) Group E: 15 women with no treatment control). After 3 months, all the patients were reevaluated. In those ones whose cysts remained, cyst aspiration guided by ultrasonography was indicated. After 3 extra months, the women were submitted to a new USG examination and in those whose cysts still remained, surgery was performed. All the patients were followed for one year. Results: There was no significant difference among the groups of hormonal treatment. The use of medication promoted a significant influence in the treatment outcomes. We also noted that the cyst aspiration was effective in reducing the size of the cysts after 9 months of follow up. Seven per cent (7%) of the patients have had immediate indication for surgery. Among those who was submitted to cyst aspiration, 19.3% had to be resubmitted to treatment because of re-incidence of the cyst, whereas, 73.2% avoid the need for surgery. Conclusions: The proportion of subjects treated with hormones and/or cyst aspiration, with no need for surgery, was of 73.2%. The influence of medication/associated disease in the treatments without surgery was significant. The reduction of size of the cysts because of the hormonal and/or aspiration treatment was significant, which was observed after 9 months of therapy.
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"Avaliação do tratamento hormonal e/ou intervencionista por punção nos tumores císticos de ovários" / Evaluation of hormonal treatment and/or intervention through aspiration of ovarian cystic tumorsLúcia Helena Chnee 06 September 2006 (has links)
Objetivo: O objetivo deste estudo foi avaliar em mulheres com tumores císticos de ovário, a proporção que, somente com o tratamento clínico e/ou punção, não necessitaram de cirurgia; a influência da medicação e das doenças associadas na indicação de cirurgia e se a punção reduziu significativamente o tamanho dos cistos. Casuística e métodos: Selecionaram-se 71 mulheres com idade entre 19 e 70 anos de idade, portadoras de tumores císticos de ovário maior que 5 cm, com características de benignidade ao ultra-som transvaginal com Doppler colorido e pulsado e com perfil endócrino e marcadores séricos tumorais normais. Foram divididas em cinco grupos: 1) Grupo A: 15 mulheres que fizeram uso de acetato de noretisterona; 2) Grupo B: 13 mulheres que fizeram uso de acetato de medroxiprogesterona; 3) Grupo C: 14 mulheres que utilizaram contraceptivo oral; 4) Grupo D: 15 mulheres que foram tratadas com análogo de GnRH e 5) Grupo E: 14 mulheres que não fizeram uso de medicação. Todos os grupos foram acompanhados por um ano. No final do primeiro trimestre, se o cisto persistiu, foi realizada a punção. No final do segundo trimestre, se houve recidiva do cisto, foi indicada cirurgia. As pacientes tiveram alta após um ano de acompanhamento com o tratamento do cisto concluído. Resultados: Não houve diferenças significantes entre os cinco grupos. Constatou-se que a condição de uso de medicação para doença associada teve influência significativa no resultado dos tratamentos. Verificou-se que a redução do tamanho do cisto com a punção foi efetiva após 9 meses de acompanhamento. Observou-se que 7% das mulheres tiveram indicação direta para cirurgia sem a punção, portanto, a proporção de recidiva da punção foi de 19,3% enquanto a porcentagem de mulheres que não fizeram a cirurgia foi de 73,2%. Conclusão: A proporção de mulheres que responderam adequadamente somente com o tratamento clínico e/ou a punção, não necessitando pois de cirurgia foi de 73,2%. A influência da medicação/ doença associada no tratamento não cirúrgico foi significativa. A redução do tamanho dos cistos benignos em função do tratamento instituído incluindo a punção foi significativa, a qual foi observada após 9 meses de tratamento. / Objectives: To evaluate the rate of women with ovarian cystic tumors submitted to diferent regimens of hormonal treatment and/or aspiration that didnt need surgery. To access the effectiveness of ovarian cyst aspiration guided by ultrasonography (USG) and to study the influence of medication and associated diseases in the need for surgery. Patients and Methods: Seventy one (71) women, in an age range from 19 to 70 years, diagnosed with ovarian cysts larger than 5 cm in length, with benign aspect, examined using an ultrasonographic transvaginal probe and color Doppler. All the women have been submitted to measurements of ser um tumor markers and hormonal levels. They were grouped in five different categories: 1) Group A: 15 women treated with noretisterone acetate; 2) Group B: 13 subjects treated with medrooxiprogesterone acetate; 3) Group C: 14 patients treated with combined oral contraceptive; 4) Group D: 15 women treated with GnRH analog, and 5) Group E: 15 women with no treatment control). After 3 months, all the patients were reevaluated. In those ones whose cysts remained, cyst aspiration guided by ultrasonography was indicated. After 3 extra months, the women were submitted to a new USG examination and in those whose cysts still remained, surgery was performed. All the patients were followed for one year. Results: There was no significant difference among the groups of hormonal treatment. The use of medication promoted a significant influence in the treatment outcomes. We also noted that the cyst aspiration was effective in reducing the size of the cysts after 9 months of follow up. Seven per cent (7%) of the patients have had immediate indication for surgery. Among those who was submitted to cyst aspiration, 19.3% had to be resubmitted to treatment because of re-incidence of the cyst, whereas, 73.2% avoid the need for surgery. Conclusions: The proportion of subjects treated with hormones and/or cyst aspiration, with no need for surgery, was of 73.2%. The influence of medication/associated disease in the treatments without surgery was significant. The reduction of size of the cysts because of the hormonal and/or aspiration treatment was significant, which was observed after 9 months of therapy.
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