scholarly journals P04.75 Tibolone, an estrogenic progestin of hormone replacement therapy reduces colony formation and 3-dimensional spheroid S-phase in C6 rat glioma in vitro

2018 ◽  
Vol 20 (suppl_3) ◽  
pp. iii297-iii297
Author(s):  
M A Altinoz ◽  
A Bilir ◽  
A Ozpinar ◽  
O Baskan ◽  
I Elmaci
Keyword(s):  
Hormone Replacement Therapy ◽  
Replacement Therapy ◽  
Colony Formation ◽  
Hormone Replacement ◽  
S Phase ◽  
Rat Glioma ◽  
3 Dimensional

Association between hormone replacement therapy and dementia: is it time to forget?

2005 ◽  
Vol 17 (2) ◽  
pp. 155-164 ◽  
Author(s):  
Osvaldo P. Almeida ◽  
Leon Flicker
Keyword(s):  
Hormone Replacement Therapy ◽  
Replacement Therapy ◽  
Observational Studies ◽  
Animal Studies ◽  
Hormone Replacement ◽  
Health Events ◽  
Increased Risk ◽  
Estrogen Plus Progestin ◽  
History Of

The results of in vitro and animal studies provide a strong rationale for the use of hormone replacement therapy (HRT) to prevent dementia and Alzheimer's disease (AD). In humans, the results of 16 observational studies are consistent with the hypothesis that estrogen use reduces the risk of AD by 10 to 60%. However, women who are prescribed HRT are less likely to have hypertension, diabetes and history of stroke than nonusers. As all of these factors have been associated with increased risk of dementia (including AD), this “prescription bias” may have a significant impact on the results of observational studies. Randomized trials are designed with the aim of avoiding many of the potential biases and confounding (measured or unmeasured) of observational studies. The results of the Women's Health Initiative Memory Study (WHIMS) indicate that HRT (estrogen plus progestin or estrogen alone) increases the risk of dementia (hazard ratio, HR=1.8, 95% CI=1.2–2.6). Taking into account the results of the WHIMS and the adverse health events associated with the use of estrogen plus progestin or estrogen alone, we conclude that HRT cannot be recommended as a safe and effective strategy to prevent dementia.

The effectiveness of different protocols of preparation of the endometrium when transferring vitrified/warmed embryos

2017 ◽  
pp. 30-32
Author(s):  
V.Y. Parashchuk ◽  
◽  
A.S. Lutsky ◽  
N.G. Gryshchenko ◽  
◽  
...  
Keyword(s):  
Hormone Replacement Therapy ◽  
In Vitro Fertilization ◽  
Replacement Therapy ◽  
Embryo Transfer ◽  
Ovarian Hyperstimulation Syndrome ◽  
Hormone Replacement ◽  
Implantation Rate ◽  
Vitro Fertilization ◽  
Frozen Embryos

Currently, there is a tendency toward increasing usage of criocycles in programs of in vitro fertilization. This approach allows to achieve pregnancy as well as prevent the development of ovarian hyperstimulation syndrome and utilize the pre-implantation genetic diagnostics. The objective: to improve the efficiency of in vitro fertilization treatment cycles with transferring of cryopreserved/warmed embryos into the uterus. Patients and methods. The study of 824 treatment cycles (in natural menstrual cycle, in cycle with hormone replacement therapy, after egg donation, in natural cycle without embryo transfer in «fresh» cycle, in cycle with hormone replacement therapy without embryo transfer in «fresh» cycle). Vitrification and cryopreservation method. Results. The analysis of the study results has shown that the implantation rate of frozen embryos in the natural cycle is higher than in the cycle with hormone replacement therapy. The implantation rate of frozen embryos after the use of agonist gonadotropin-releasing hormone as a trigger of final maturation of the agonist is higher than that of human chorionic gonadotropin, which allows us to consider vitrification as an effective tool that provides great flexibility of conducting controlled ovarian stimulation cycles and prevention of ovarian hyperstimulation syndrome. Conclusion. The effectiveness of frozen embryo transfer protocols gives us grounds to assert that the optimum cycle for the transfer is a cycle without stimulation. Key words: in vitro fertilization, the endometrium, frozen embryo implantation.

scholarly journals In vitro and in vivo evaluations of biodegradable implants for hormone replacement therapy: Effect of system design and PK-PD relationship

2001 ◽  
Vol 2 (3) ◽  
pp. 55-65 ◽  
Author(s):  
Senshang Lin ◽  
Pi-Yun Chao ◽  
Yie W. Chien ◽  
Amyn Sayani ◽  
Sandeep Kumar ◽  
...  
Keyword(s):  
Hormone Replacement Therapy ◽  
System Design ◽  
Replacement Therapy ◽  
Hormone Replacement ◽  
Biodegradable Implants ◽  
Therapy Effect

Low biologic aggressiveness in breast cancer in women using hormone replacement therapy.

1998 ◽  
Vol 16 (9) ◽  
pp. 3115-3120 ◽  
Author(s):  
K Holli ◽  
J Isola ◽  
J Cuzick
Keyword(s):  
Breast Cancer ◽  
Hormone Replacement Therapy ◽  
Replacement Therapy ◽  
Tumor Size ◽  
Hormone Replacement ◽  
Breast Tumors ◽  
S Phase ◽  
Proliferation Rate ◽  
Tumor Aggressiveness ◽  
Er Positive

PURPOSE Hormone replacement therapy (HRT) has been associated with an increased risk for breast cancer. Cancers in women who use HRT are often less advanced, and lower mortality has been reported in those who use HRT than in nonusers. We sought to explain this by a comparison of indicators of tumor aggressiveness in patients who received HRT with those in patients who did not. PATIENTS AND METHODS A population-based cohort of 477 postmenopausal women with breast cancer were interviewed for the use, type, and duration of HRT. Clinical variables and indicators of tumor aggressiveness (histologic grade, hormone receptors, DNA ploidy, S-phase fraction, and c-erbB-2 oncoprotein overexpression) were analyzed. RESULTS Breast tumors from HRT users were smaller (odds ratio, 0.47; P=.005), had better histologic differentiation (P=.04), and had a lower proliferation rate (S-phase fraction, P=.009) than tumors from nonusers. These differences persisted after adjustments for age and method of diagnosis (mammography screening v self-referral) by multiple logistic regression. No significant differences were observed in the estrogen (ER) or progesterone receptor content, c-erbB-2 oncogene overexpression, or axillary node involvement. A subgroup analysis showed that the tumor proliferation rates among HRT users were significantly lower only if HRT had been used at the time of diagnosis (P=.001). The type of HRT (estrogen v combination of estrogen and progesterone) was not associated with any clinical parameter or tumor phenotype. The association of HRT with lower proliferation rate and smaller tumor size was exclusively caused by ER-positive tumors (P=.0001 and P=.0035 v P > .1, respectively). CONCLUSION The results indicate that breast cancer in women who receive HRT is biologically less aggressive than those without previous HRT. The lower cell-proliferation rate and smaller tumor size found in ER-positive tumors from current HRT users suggest a direct ER-mediated growth inhibitory effect of HRT on established breast tumors. This may at least partly explain why breast cancer in HRT users has a more favorable clinical course.

scholarly journals Age-related changes in human oestrogen receptor α function and levels in osteoblasts

1998 ◽  
Vol 333 (3) ◽  
pp. 787-794 ◽  
Author(s):  
Michael A. ANKROM ◽  
Julie A. PATTERSON ◽  
Patricia Y. d'AVIS ◽  
Ulrich K. VETTER ◽  
Marc R. BLACKMAN ◽  
...  
Keyword(s):  
Hormone Replacement Therapy ◽  
Replacement Therapy ◽  
Older Women ◽  
Hormone Replacement ◽  
Fold Increase ◽  
Mean Value ◽  
Younger Women ◽  
Age Related ◽  
Cell Strains

Oestrogen receptors (ERs) are present in human osteoblasts and mediate anti-resorptive effects on bone. Human osteoblast-like cells derived from different aged healthy female donors not on hormone replacement therapy were utilized under well-defined conditions in vitro to investigate ER function and levels. Treatment with 0.1 nM oestradiol-17β of cell strains derived from eight young women (less than 50 years of age) increased hydroxyproline levels significantly [an average (2.2±0.1 S.E.M.)-fold increase], whereas cells derived from nine older women (more than 50 years of age) were not significantly affected. Similarly, cell strains, derived from younger women, transfected with a consensus oestrogen-responsive element linked to chloramphenicol acetyltransferase exhibited a greater response to oestrogen than strains derived from older women. When basal ERα levels were measured by enzyme immunoassay and normalized on a per cell basis, osteoblast-like strains derived from younger women (n = 24) had a mean value of 2.54±0.16 fmol of ERα per 106 cells. In contrast, strains derived from older women (n = 20) had a mean value of 5.44±0.48 fmol of ERα per 106 cells. An age-related increase in ERα number was also observed in human skin-derived fibroblasts and directly in dermal biopsies from women not on hormone replacement therapy. The results demonstrate ligand concentration-dependent ERα induction and indicate a loss of receptor regulation and diminution of ligand–receptor signal transduction with increasing donor age.

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