833 resultados para estradiol cypionate


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Vasomotor hot flushes are complained of by approximately 75% of postmenopausal women, but their frequency and severity show great individual variation. Hot flushes have been present in women attending observational studies showing cardiovascular benefit associated with hormone therapy use, whereas they have been absent or very mild in randomized hormone therapy trials showing cardiovascular harm. Therefore, if hot flushes are a factor connected with vascular health, they could perhaps be one explanation for the divergence of cardiovascular data in observational versus randomized studies. For the present study 150 healthy, recently postmenopausal women showing a large variation in hot flushes were studied in regard to cardiovascular health by way of pulse wave analysis, ambulatory blood pressure and several biochemical vascular markers. In addition, the possible impact of hot flushes on outcomes of hormone therapy was studied. This study shows that women with severe hot flushes exhibit a greater vasodilatory reactivity as assessed by pulse wave analysis than do women without vasomotor symptoms. This can be seen as a hot flush-related vascular benefit. Although severe night-time hot flushes seem to be accompanied by transient increases in blood pressure and heart rate, the diurnal blood pressure and heart rate profiles show no significant differences between women without and with mild, moderate or severe hot flushes. The levels of vascular markers, such as lipids, lipoproteins, C-reactive protein and sex hormone-binding globulin show no association with hot flush status. In the 6-month hormone therapy trial the women were classified as having either tolerable or intolerable hot flushes. These groups were treated in a randomized order with transdermal estradiol gel, oral estradiol alone or in combination with medroxyprogesterone acetate, or with placebo. In women with only tolerable hot flushes, oral estradiol leads to a reduced vasodilatory response and increases in 24-hour and daytime blood pressures as compared to women with intolerable hot flushes receiving the same therapy. No such effects were observed with the other treatment regimes or in women with intolerable hot flushes. The responses of vascular biomarkers to hormone therapy are unaffected by hot flush status. In conclusion, hot flush status contributes to cardiovascular health before and during hormone therapy. Severe hot flushes are associated with an increased vasodilatory, and thus, a beneficial vascular status. Oral estradiol leads to vasoconstrictive changes and increases in blood pressure, and thus to possible vascular harm, but only in women whose hot flushes are so mild that they would probably not lead to the initiation of hormone therapy in clinical practice. Healthy, recently postmenopausal women with moderate to severe hot flushes should be given the opportunity to use hormone therapy alleviate hot flushes, and if estrogen is prescribed for indications other than for the control of hot flushes, transdermal route of administration should be favored.

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Since national differences exist in genes, environment, diet and life habits and also in the use of postmenopausal hormone therapy (HT), the associations between different hormone therapies and the risk for breast cancer were studied among Finnish postmenopausal women. All Finnish women over 50 years of age who used HT were identified from the national medical reimbursement register, established in 1994, and followed up for breast cancer incidence (n= 8,382 cases) until 2005 with the aid of the Finnish Cancer Registry. The risk for breast cancer in HT users was compared to that in the general female population of the same age. Among women using oral or transdermal estradiol alone (ET) (n = 110,984) during the study period 1994-2002 the standardized incidence ratio (SIR) for breast cancer in users for < 5 years was 0.93 (95% confidence interval (CI) 0.80–1.04), and in users for ≥ 5 years 1.44 (1.29–1.59). This therapy was associated with similar rises in ductal and lobular types of breast cancer. Both localized stage (1.45; 1.26–1.66) and cancers spread to regional nodes (1.35; 1.09–1.65) were associated with the use of systemic ET. Oral estriol or vaginal estrogens were not accompanied with a risk for breast cancer. The use of estrogen-progestagen therapy (EPT) in the study period 1994-2005 (n= 221,551) was accompanied with an increased incidence of breast cancer (1.31;1.20-1.42) among women using oral or transdermal EPT for 3-5 years, and the incidence increased along with the increasing duration of exposure (≥10 years, 2.07;1.84-2.30). Continuous EPT entailed a significantly higher (2.44; 2.17-2.72) breast cancer incidence compared to sequential EPT (1.78; 1.64-1.90) after 5 years of use. The use of norethisterone acetate (NETA) as a supplement to estradiol was accompanied with a higher incidence of breast cancer after 5 years of use (2.03; 1.88-2.18) than that of medroxyprogesterone acetate (MPA) (1.64; 1.49-1.79). The SIR for the lobular type of breast cancer was increased within 3 years of EPT exposure (1.35; 1.18-1.53), and the incidence of the lobular type of breast cancer (2.93; 2.33-3.64) was significantly higher than that of the ductal type (1.92; 1.67-2.18) after 10 years of exposure. To control for some confounding factors, two case control studies were performed. All Finnish women between the ages of 50-62 in 1995-2007 and diagnosed with a first invasive breast cancer (n= 9,956) were identified from the Finnish Cancer Registry, and 3 controls of similar age (n=29,868) without breast cancer were retrieved from the Finnish national population registry. Subjects were linked to the medical reimbursement register for defining the HT use. The use of ET was not associated with an increased risk for breast cancer (1.00; 0.92-1.08). Neither was progestagen-only therapy used less than 3 years. However, the use of tibolone was associated with an elevated risk for breast cancer (1.39; 1.07-1.81). The case-control study confirmed the results of EPT regarding sequential vs. continuous use of progestagen, including progestagen released continuously by an intrauterine device; the increased risk was seen already within 3 years of use (1.65;1.32-2.07). The dose of NETA was not a determinant as regards the breast cancer risk. Both systemic ET, and EPT are associated with an elevation in the risk for breast cancer. These risks resemble to a large extent those seen in several other countries. The use of an intrauterine system alone or as a complement to systemic estradiol is also associated with a breast cancer risk. These data emphasize the need for detailed information to women who are considering starting the use of HT.

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Without estrogen action, the fusion of the growth plates is postponed and statural growth continues for an exceptionally long time. Aromatase inhibitors, blockers of estrogen biosynthesis, have therefore emerged as a new potential option for the treatment of children with short stature. We investigated the efficacy of the aromatase inhibitor letrozole in the treatment of boys with idiopathic short stature (ISS) using a randomised, placebo-controlled, double-blind research setting. A total of 30 boys completed the two-year treatment. By decreasing estrogen-mediated central negative feedback, letrozole increased gonadotrophin and testosterone secretion in pubertal boys, whereas the pubertal increase in IGF-I was inhibited. Treatment with letrozole effectively delayed bone maturation and increased predicted adult height by 5.9 cm (P0.001), while placebo had no effect on either parameter. The effect of letrozole treatment on near-final height was studied in another population, in boys with constitutional delay of puberty, who received letrozole (n=9) or placebo (n=8) for one year, in combination with low-dose testosterone for six months during adolescence. The mean near-final height of boys randomised to receive testosterone and letrozole was significantly greater than that of boys who received testosterone and placebo (175.8 vs. 169.1 cm, P=0.04). As regards safety, treatment effects on bone health, lipid metabolism, insulin sensitivity, and body composition were monitored in boys with ISS. During treatment, no differences in bone mass accrual were evident between the treatment groups, as evaluated by dual-energy x-ray absorptiometry measurements of the lumbar spine and femoral neck. Bone turnover and cortical bone growth, however, were affected by letrozole treatment. As indicated by differences in markers of bone resorption (U-INTP) and formation (S-PINP and S-ALP), the long-term rate of bone turnover was lower in letrozole-treated boys, despite their more rapid advancement in puberty. Letrozole stimulated cortical bone growth in those who progressed in puberty: the metacarpal index (MCI), a measure of cortical bone thickness, increased more in letrozole-treated pubertal boys than in placebo-treated pubertal boys (25% vs. 9%, P=0.007). The change in MCI correlated positively with the mean testosterone-to-estradiol ratio. In post-treatment radiographic evaluation of the spine, a high rate of vertebral deformities - mild anterior wedging and mild compression deformities - were found in both placebo and letrozole groups. In pubertal boys with ISS treated with letrozole, stimulated testosterone secretion was associated with a decrease in the percentage of fat mass and in HDL-cholesterol, while LDL-cholesterol and triglycerides remained unchanged. Insulin sensitivity, as evaluated by HOMA-IR, was not significantly affected by the treatment. In summary, treatment with the aromatase inhibitor letrozole effectively delayed bone maturation and increased predicted adult height in boys with ISS. Long-term follow-up data of boys with constitutional delay of puberty, treated with letrozole for one year during adolescence, suggest that the achieved gain in predicted adult height also results in increased adult height. However, until the safety of aromatase inhibitor treatment in children and adolescents is confirmed, such treatment should be considered experimental.

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Paikallisesti levinnyttä (T3-4 M0) ja luustoon levinnyttä (T1-4 M1) eturauhassyöpää sairastaneet potilaat satunnaistettiin kirurgiseen kastraatioon (orkiektomia) tai lääkkeelliseen kastraatioon lihaksensisäisellä polyestradiolifosfaatilla (PEP) annoksella 240 mg/kk. Verrattiin hoitojen kliinistä tehoa sekä sydän- ja verisuonikomplikaatioita (SV-komplikaatioita). Verrattiin myös hoitoa edeltäviä plasman testosteroni (T) ja estradioli (E2) pitoisuuksia T3-4 M0 ja T1-4 M1 potilaiden välillä sekä selvitettiin potilaiden yleistilan vaikutusta näihin hormonitasoihin. Lopuksi luotiin T1-4 M1 potilaille eturauhassyövän aiheuttaman kuoleman ennusteellinen riskiluokittelu kolmeen riskiryhmään käyttämällä hoitoa edeltäviä ennustetekijöitä. Kliinisessä tehossa ei orkiektomian ja PEP-hoidon välillä todettu tilastollisesti merkitsevää eroa. Odotetusti T1-4 M1 potilaiden ennuste oli huonompi kuin T3-4 M0 potilaiden. T1-4 M1 potilailla ei ollut SV-kuolemissa hoitoryhmien välillä tilastollista eroa, mutta ei-tappavia SV-komplikaatioita oli PEP ryhmässä (5.9%) enemmän kuin orkiektomia ryhmässä (2.0%). T3-4 M0 potilailla PEP-hoitoon liittyi tilastollisesti merkitsevä SV-kuolleisuus riski orkiektomiaan verrattuna (p = 0.001). PEP ryhmässä 67% kuolemista oli akuutteja sydäninfarkteja. Tämä PEP hoitoon liittyvä sydäninfarktiriski (mukaan lukien myös ei-tappavat sydäninfarktit) oli merkitsevästi pienempi potilailla, joiden hoitoa edeltävä E2 taso oli vähintään 93 pmol/l (p = 0.022). E2 taso oli merkitsevästi matalampi T1-4 M1 potilailla (74.7 pmol/l) kuin T3-4 M0 potilailla (87.9 pmol/l), mutta vastaavaa eroa ei ollut T tasoissa. Sekä T3-4 M0 että T1-4 M1 potilailla yleistilan lasku osittain selitti yksilöllisen T ja E2 tasojen laskun. Eturauhassyövän aiheuttaman kuoleman riskiryhmäluokittelu (Rg) kolmeen ryhmään luotiin käyttämällä alkalista fosfataasia (AFOS), prostata spesifistä antigeenia (PSA), laskoa (La) ja potilaan ikää. Yksi riskipiste annettiin, jos AFOS > 180 U/l (tällä hetkellä käytössä olevalla menetelmällä AFOS > 83 U/l), PSA > 35 µg/l, La > 80 mm/h ja ikä < 60 vuotta. Lopuksi pisteet laskettiin yhteen. Muodostettiin seuraavat ryhmät: Rg-a (0 -1 riskipistettä), Rg-b (2 riskipistettä) ja Rg-c (3 – 4 riskipistettä). Eturauhassyövän aiheuttama kuoleman riski lisääntyi merkitsevästi siirryttäessä riskiryhmästä seuraavaan (p < 0.001). Rg-luokittelu oli kliinisesti käytännöllinen ja hyvä havaitsemaan huonon ennusteen potilaat.

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Intrahepatic cholestasis of pregnancy (ICP) is the most common cholestatic liver disease during pregnancy. The reported incidence varies from 0.4 to 15% of full-term pregnancies. The etiology is heterogeneous but familial clustering is known to occur. Here we have studied the genetic background, epidemiology, and long-term hepatobiliary consequences of ICP. In a register-based nation-wide study (n=1 080 310) the incidence of ICP was 0.94% during 1987-2004. A slightly higher incidence, 1.3%, was found in a hospital-based series (n=5304) among women attending the University Hospital of Helsinki in 1992-1993. Of these 16% (11/69) were familial and showed a higher (92%) recurrence rate than the sporadic (40%) cases. In the register-based epidemiological study, advanced maternal age and, to a lesser degree, parity were identified as new risk factors for ICP. The risk was 3-fold higher in women >39 years of age compared to women <30 years. Multiple pregnancy also associated with an elevated risk. In a genetic study we found no association of ICP with the genes regulating bile salt transport (ABCB4, ABCB11 and ATP8B1). The livers of postmenopausal women with a history of ICP tolerated well the short-term exposure to oral and transdermal estradiol, although the doses used were higher than those in routine clinical use. The response of serum levels of sex hormone-binding globulin (SHBG) to oral estradiol was slightly reduced in the ICP group. Transdermal estradiol had no effect on C-reactive protein (CRP) or SHBG. A number of liver and biliary diseases were found to be associated with ICP. Women with a history of ICP showed elevated risks for non-alcoholic liver cirrhosis (8.2 CI 1.9-36), cholelithiasis and cholecystitis (3.7 CI 3.2-4.2), hepatitis C (3.5 CI 1.6-7.6) and non-alcoholic pancreatitis (3.2 CI 1.7-5.7). In conclusion, ICP complicates around 1% of all full-term pregnancies in Finland and its incidence has remained unchanged since 1987. It is familial in 16% of cases with a higher recurrence rate. Although the cause remains unknown, several risk factors, namely advanced maternal age, parity and multiple pregnancies, can be identified. Both oral and transdermal regimens of postmenopausal hormone therapy (HT) are safe for women with a history of ICP when liver function is considered. Some ICP patients are at risk of other liver and biliary diseases and, contrary to what has been thought, a follow-up is warranted.

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Germ cell tumors occur both in the gonads of both sexes and in extra-gonadal sites during adoles-cence and early adulthood. Malignant ovarian germ cell tumors are rare neoplasms accounting for less than 5% of all cases of ovarian malignancy. In contrast, testicular cancer is the most common malignancy among young males. Most of patients survive the disease. Prognostic factors of gonadal germ cell tumors include histology, clinical stage, size of the primary tumor and residua, and levels of tumor markers. Germ cell tumors include heterogeneous histological subgroups. The most common subgroup includes germinomas (ovarian dysgerminoma and testicular seminoma); other subgroups are yolk sac tumors, embryonal carcinomas, immature teratomas and mixed tumors. The origin of germ cell tumors is most likely primordial germ cells. Factors behind germ cell tumor development and differentiation are still poorly known. The purpose of this study was to define novel diagnostic and prognostic factors for malignant gonadal germ cell tumors. In addition, the aim was to shed further light into the molecular mechanisms regulating gonadal germ cell tumorigenesis and differentiation by studying the roles of GATA transcription factors, pluripotent factors Oct-3/4 and AP-2γ, and estrogen receptors. This study revealed the prognostic value of CA-125 in malignant ovarian germ cell tumors. In addition advanced age and residual tumor had more adverse outcome. Several novel markers for histological diagnosis were defined. In the fetal development transcription factor GATA-4 was expressed in early fetal gonocytes and in testicular carcinoma precursor cells. In addition, GATA-4 was expressed in both gonadal germinomas, thus it may play a role in the development and differentiation of the germinoma tumor subtype. Pluripotent factors Oct-3/4 and AP-2γ were expressed in dysgerminomas, thus they could be used in the differential diagnosis of the germ cell tumors. Malignant ovarian germ cell tumors expressed estrogen receptors and their co-regulator SNURF. In addition, estrogen receptor expression was up-regulated by estradiol stimulation. Thus, gonadal steroid hormone burst in puberty may play a role in germ cell tumor development in the ovary. This study shed further light in to the molecular pathology of malignant gonadal germ cell tumors. In addition, some novel diagnostic and prognostic factors were defined. This data may be used in the differential diagnosis of germ cell tumor patients.

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Sulfotransferases (SULTs) and UDP-glucuronosyltransferases (UGTs) are important detoxification enzymes and they contribute to bioavailability and elimination of many drugs. SULT1A3 is an extrahepatic enzyme responsible for the sulfonation of dopamine, which is often used as its probe substrate. A new method for analyzing dopamine-3-O-sulfate and dopamine-4-O-sulfate by high-performance liquid chromatography was developed and the enzyme kinetic parameters for their formation were determined using purified recombinant human SULT1A3. The results show that SULT1A3 strongly favors the 3-hydroxy group of dopamine, which indicates that it may be the major enzyme responsible for the difference between the circulating levels of dopamine sulfates in human blood. All 19 known human UGTs were expressed as recombinant enzymes in baculovirus infected insect cells and their activities toward dopamine and estradiol were studied. UGT1A10 was identified as the only UGT capable of dopamine glucuronidation at a substantial level. The results were supported by studies with human intestinal and liver microsomes. The affinity was low indicating that UGT1A10 is not an important enzyme in dopamine metabolism in vivo. Despite the low affinity, dopamine is a potential new probe substrate for UGT1A10 due to its selectivity. Dopamine was used to study the importance of phenylalanines 90 and 93 in UGT1A10. The results revealed distinct effects that are dependent on differences in the size of the side chain and on the differences in their position within the protein. Examination of twelve mutants revealed lower activity in all of them. However, the enzyme kinetic studies of four mutants showed that their affinities were similar to that of UGT1A10 suggesting that F90 and F93 are not directly involved in dopamine binding in the active site. The glucuronidation of β-estradiol and epiestradiol (α-estradiol) was studied to elucidate how the orientation of the 17-OH group affects conjugation at the 3-OH or the 17-OH of either diastereomer. The results show that there are clear differences in the regio- and stereoselectivities of UGTs. The most active isoforms were UGT1A10 and UGT2B7 demonstrating opposite regioselectivity. The stereoselectivities of UGT2Bs were more complex than those of UGT1As. The amino acid sequences of the human UGTs 1A9 and 1A10 are 93% identical, yet there are large differences in their activity and substrate selectivity. Several mutants were constructed to identify the residues responsible for the activity differences. The results revealed that the residues between Leu86 and Tyr176 of UGT1A9 determine the differences between UGT1A9 and UGT1A10. Phe117 of UGT1A9 participated in 1-naphthol binding and the residues at positions 152 and 169 contributed to the higher glucuronidation rates of UGT1A10. In summary, the results emphasize that the substrate selectivities, including regio- and stereoselectivities, of UGTs are complex and they are controlled by many amino acids rather than one critical residue.

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Preovulatory follicular atresia was studied using pregnant mare serum gonadotropin (PMSG)-primed rats (15 IU/rat) which were deprived of hormonal support either by allowing the metabolic clearance of the PMSG or by injecting a specific PMSG antiserum (PMSG a/s). Atresia was monitored by an increase in lysosomal cathepsin-D activity and a decrease in the receptor activity of the granulosa cells (GC) isolated from the preovulatory follicles. It was shown that the increase in lysosomal activity and the decrease in receptor activity seen at 96 h after PMSG (or PMSG plus PMSG a/s) could be arrested both by follicle stimulating hormone (FSH) and luteinizing hormone (LH). Injection of cyanoketone or clomiphene citrate together with FSH/LH prevented this 'rescue' suggesting a role for estrogens in the regulation of atresia. Although the administration of estradiol-17 beta (20 micrograms/rat) together with PMSG a/s could show a 'rescue effect' in terms of reduction in cathepsin-D activity the gonadotropin receptor activities of these granulosa cells were not restored. The injection of dihydrotestosterone (DHT) to 48 h PMSG-primed rats induced atresia as noted by an increase in cathepsin-D activity. However, the exogenous administration of FSH along with DHT prevented this atretic effect suggesting that DHT is not having a direct effect on atresia. Determination of androgen: estrogen content of the granulosa cells and an analysis of the individual profile of androgen and estrogen revealed that the increase in cathepsin-D activity could be correlated only with the decrease in GC estrogen content. This along with the observation that GC showed a loss of estrogen synthesis well before the increase in cathepsin-D activity strongly points out that the lack of estrogen rather than an increase in androgen is the principle factor responsible for the atresia of preovulatory follicles in the rat.

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The effect of neutralizing endogenous follicle stimulating hormone (FSH) or luteinizing hormone (LH) with specific antisera on the Image Image and Image Image synthesis of estrogen in the ovary of cycling hamster was studied. Neutralization of FSH or LH on proestrus resulted in a reduction in the estradiol concentration of the ovary on diestrus-2 and next proestrus, suggesting an impairment in follicular development.Injection of FSH antiserum at 0900 h of diestrus-2 significantly reduced the ovarian estradiol concentration within 6–7 h. Further, these ovaries on incubation with testosterone(T) Image Image at 1600 h of the same day or the next day synthesized significantly lower amounts of estradiol, compared to corresponding control ovaries. Although testosterone itself, in the absence of endogenous FSH, could stimulate estrogen synthesis to some extent, FSH had to be supplemented with T to restore estrogen synthesis to the level seen in control ovaries incubated with T. Lack of FSH thus appeared to affect the aromatization step in the estrogen biosynthetic pathway in the ovary of hamster on diestrus-2. In contrast to this, FSH antiserum given on the morning of proestrus had no effect on the Image Image and Image Image synthesis of estrogen, when examined 6–7 h later. The results suggest that there could be a difference in the need for FSH at different times of the cycle.Neutralization of LH either on diestrus-2 or proestrus resulted in a drastic reduction in estradiol concentration of the ovary. This block was at the level of androgen synthesis, since supplementing testosterone alone Image Image could stimulate estrogen synthesis to a more or less similar extent as in the ovaries of control hamsters.

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Initiation of follicular growth by specific hormonal stimuli in ovaries of immature rats and hamsters was studied by determining the rate of incorporation of3H-thymidine into ovarian DNAin vitro. Incorporation was considered as an index of DNA synthesis and cell multiplication. A single injection of pregnant mare serum gonadotropin could thus maximally stimulate by 18 hr3H-thymidine incorporation into DNA of the ovary of immature hamsters. Neutralization of pregnant mare serum gonadotropin by an antiserum to ovine follicle stimulating hormone only during the initial 8–10 hr and not later could inhibit the increase in3H-thymidine incorporationin vitro observed at 18 hr, suggesting that the continued presence of gonadotropin stimulus was not necessary for this response. The other indices of follicular growth monitored such as ovarian weight, serum estradiol and uterine weight showed discernible increase at periods only after the above initial event. A single injection of estrogen (diethyl stilbesterol or estradiol-l7β) could similarly cause 18 hr later, a stimulation in the rate of incorporation of3H-thymidine into DNAin vitro in ovaries of immature rats. The presence of endogenous gonadotropins, however, was obligatory for observing this response to estrogen. Evidence in support of the above was two-fold: (i) administration of antiserum to follicle stimulating hormone or luteinizing hormone along with estrogen completely inhibited the increase in3H-thymidine incorporation into ovarian DNAin vitro; (ii) a radioimmunological measurement revealed following estrogen treatment, the presence of a higher concentration of endogenous follicle stimulating hormone in the ovary. Finally, administration of varying doses of ovine follicle stimulating hormone along with a constant dose of estrogen to immature rats produced a dose-dependent increment in the incorporation of3H-thymidine into ovarian DNAin vitro. These observations suggested the potentiality of this system for developing a sensitive bioassay for follicle stimulating hormone.

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Estrogens the female sex hormones have numerous biological actions. Estradiol is the most abundant estrogen in women before menopause. It influences the development, maturation and function of the female reproductive tract. It also plays a role in mammary cancer. Accordingly determinations of estradiol level in body fluids assist in the evaluation of ovarian function and diagnosis for malignancies. Estriol is the primary estrogen in pregnant women and secreted from the fetoplacental unit. Measurement of estriol in maternal body fluids is the basis of fetoplacental monitoring test. Concentration of estrogens in body fluids is determined by immunoassay. Accuracy of this measurement depends on the availability of a specific antibody. As estrogens are not antigenic, their derivatives (haptens) are coupled with a carrier and this hapten-protein conjugate is used to generate antibodies. Specificity of the generated antibody largely depends on the structure of hapten. Therefore the synthesis of a hapten with a right structure is crucial for the accurate measurement of a steroid. We have synthesised new haptens for estradiol and estriol by adding an alkyl or alkoxy side chain at the C-7 of estrane skeleton. The side chains carry a terminal amino group, which can be used for conjugation with a carrier molecule. Estrogens and their biosynthetic precursor androgens both exist as fatty acid esters. They are known to act as hormone storage but their physiological role is not completely known yet. Our collaborator is studying their effect in cardiovascular diseases. We synthesised fatty acid ester derivatives of several steroids in high yield by a very rapid procedure (in 1 min) under microwave irradiation in an ionic liquid (IL). An expedient regioselective hydrolysis at C-3 of estradiol diesters is also reported. 8-Isoestrogens are compounds of pharmaceutical interests, their synthesis, structure, conformation and biological activity studies are ongoing. 7-Hydroxy-8-isoestradiol and 7-alkyl ether of it were synthesised as well. During this study we have developed a selective O-debenzylation method. A mild route for selective removal of benzylic protection on phenol in presence of benzyl protected alcohol was explored.

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Adult rat Leydig cells in culture synthesize and secrete riboflavin carrier protein (RCP) as demonstrated by [S-35]-methionine incorporation into newly synthesized proteins followed by immunoprecipitation as well as specific radioimmunoassay. LH stimulates the secretion of RCP 4-fold which could be inhibited upto 75% by an aromatase inhibitor. 8-bromo-cyclic AMP and cholera toxin could mimic the LH stimulated secretion of the carrier protein. The extent of stimulation of RCP secretion brought about by exogenous estradiol-17 beta is comparable to that of LH. The antiestrogen tamoxifen, when added along with either LH or estrogen, inhibited the stimulated levels significantly. These results show that the estrogen-inducible riboflavin carrier is secreted by Leydig cells under positive regulation of LH.

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Callithrix jacchus (common marmoset) is a New World primate monkey, used as an animal model in biomedical research. Marmoset-specific follicle-stimulating hormone (FSH) preparation is required to improve superovulation protocols and to develop homologous FSH monitoring assays in these monkeys. In this study, we document the large-scale expression of recombinant marmoset FSH in methylotropic yeast, Pichia pastoris. The recombinant preparation was found to be immunologically active in Western blotting and radioimmunoassay. The preparation displayed receptor binding ability in radioreceptor assay. Based on the receptor binding ability, the yield of fermentation was estimated to be 7.2 mg/L. FSH-induced cAMP assay and estradiol assay revealed that the recombinant hormone is able to induce signal transduction. Both immunological and in vitro biological activity of marmoset FSH was found to be comparable to purified human pituitary FSH, which served as reference hormone for these assays. Thus, the study suggests that a Pichia expression system can be used for large-scale expression of bioactive recombinant marmoset FSH.

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El objetivo de este estudio fue evaluar la efectividad de dos tratamientos hormonales en la sincronización del estro en hembras caprinas bajo condiciones semi intensivas del trópico seco. Cada unidad experimental estuvo representada por una hembra caprina reproductora, cuya edad osciló entre los 3½ años con pesos promedios de 38 kg pv, se utilizó un total de 30 hembras. Estas se distribuyeron en tres tratamientos, conformados por diez unidades experimentales cada uno. Tratamiento 1 :EAZI-BREED ® -CIDR ® vía intravaginal, conteniendo 300 mg (0.3 g) de progesterona sintética (que liberó 20 mg d -1 aproximadamente) + ECP (Cipionato de Estradiol) a razón de 2.5ml, vía intramuscular (3 mg/ml) al noveno día (después de retirar el CIDR ® ), se aplicó 3ml de Lutalyse ® (PGF2α, 5 mg Dinopróstamina por ml) vía intramuscular; El segundo tratamiento fue conformada: EAZI-BREED ® -CIDR ® + Lutalyse ® (PGF2α) al retiro del CIDR ® ; Tratamiento 3: control o efecto macho (estas fueron expuestas al macho de forma continua durante toda la duración del experimento). Se detectó celo después de retirar el CIDR ® , a intervalos de 24, 48, 72 y 96 horas. Los resultados obtenidos para las variables en estudio, mostraron que la variable detección de celo fue altamente significativa (P<0.01), estado gestacional fue significativa (P<0.05); mientras que para las variables aparición de celo (h) y número de embriones, no se encontraron diferencias significativas (P˃ 0.05). La sobrevivencia embrionaria por tratamiento fue de 85% para T1, 80% para T2 y 70% para T3. El análisis financiero determino que el tratamiento T2 fue el más viable.

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Avaliamos o efeito do consumo materno de SDG (Diglicosídeo Secoisolariciresinol) e de óleo de Linhaça+SDG sobre parâmetros bioquímicos e hormonais das ratas e das proles machos e fêmeas na lactação. As ratas lactantes foram separadas em: controle (C), ração controle cuja proteína foi caseína; (SDG): ração C com 400mg de SDG/Kg de ração; OLSDG: ração C com 400mg de SDG/Kg de ração e 7% de óleo de linhaça. No 14 e 20 dias de lactação as ratas foram ordenhadas e no 21 dia foram sacrificadas por punção cardíaca. Leite e soro foram coletados para avaliação bioquímica e hormonal. Hormônios foram quantificados por radioimunoensaio. As proles machos e fêmeas foram sacrificadas aos 14 e 21 dias de idade. Os animais foram eviscerados para análise da composição corporal. Monitoramos a ingestão alimentar e a massa corporal (MC) durante o período experimental. As ratas SDG apresentaram maior gordura corporal (GC; +39%), enquanto as OLSDG menor conteúdo mineral (-20%) e trigliceridemia (TG) (-39%). As ratas SDG e OLSDG apresentaram hiperprolactinemia (+389% e 153%, respectivamente) sem alteração na concentração de estradiol. No 14 dia de lactação, o leite das ratas OLSDG apresentou menores teores de lactose(-17%) e de proteínas (-20%) e o das ratas SDG apenas menor teor de proteína (-21%). A partir do 13 dia de lactação tanto os machos quanto as fêmeas OLSDG apresentaram menor MC (-14%, -16%, respectivamente). No 14 dia de lactação os machos SDG e OLSDG apresentaram menor gordura corporal (-24%, -55%, respectivamente ) e a prole SDG maior massa de gordura visceral (+39%). Os machos SDG apresentaram maiores concentrações de TG (+105%) e hipoprolactinemia (-41%). Os machos OLSDG também apresentaram hipoprolactinemia (-41%). As fêmeas SDG e OLSDG apresentaram maior estradiol aos 14 dias (+86% e +176%) que se normalizou aos 21 dias, maior colesterolemia (+16%) e as SDG apresentaram maior trigliceridemia (+74%). Aos 21 dias os machos e as fêmeas SDG e OLSDG apresentaram menor trigliceridemia (-48%, -54%,42% e -59%, respectivamente). Os dois componentes principais da semente de linhaça produzem alterações bioquímicas e hormonais tanto nas mães, quanto nas proles, independente do sexo. Entretanto, as alterações observadas diferem entre mães e prole e de acordo com o gênero. Entre as alterações mais importantes ressaltamos a hiperprolactinemia materna que pode ser um dos motivos para a hipoprolactinemia da prole e a hipertrigliceridemia causada pela ingestão de SDG pelas mães.