estrogen receptor expression
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2022 ◽  
Vol 6 (1) ◽  
pp. 01-05
Author(s):  
Armine V. Grigoryan ◽  
Alexander B. Blazhev ◽  
Tatyana M. Betova ◽  
Aneliya A. Dimitrova

Estradiol is an estrogen steroid hormone and is produced basically within the follicles of the ovaries. The decrease in serum estrogens concentration at menopause disrupts the metabolic balance, changes the lipid profile leading to visceral obesity, which caused an increase in serum estradiol levels, through aromatase activity. Estrogen deficiency also is a reason for the development of osteoporosis.We investigated the serum estradiol levels and changes in bone alpha estrogen receptor expression in ovariectomized rats. For this purpose, we used 20 female Wistar rats at reproductive age - 2 months divided into 2 groups: group 1 (G1)-10 animals were ovariectomized and group 2 (G2)-10 of which were sham-operated. All animals of G1 showed weight gain compared to group G2. The results showed that the values of serum 17β-estradiol in rats of G1 statistically increased compared to G2 (p <0.05). Immunohistochemical analysis revealed no difference in estrogen receptor expression between the both groups. Histomorphological analysis of femur from G1 showed the presence of pronounced osteoporosis. Ovariectomy led to the development of obesity, which caused an increase in serum estradiol levels, through aromatase activity, but this process did not prevent bone tissue from developing osteoporosis.


2021 ◽  
Vol 17 (2) ◽  
pp. 14-22
Author(s):  
A. Kh. Ismagilov ◽  
A. S. Vanesyan ◽  
D. R. Khuzina

Objective: development of a predictive model based on binary regression to determine the likelihood of progression of I stage breast cancer.Materials and methods. A retrospective analysis of data of 385 patients with T1N0M0 stage breast cancer was performed. The minimum follow-up period was 120 months and the maximum made 256 months, with an average follow-up of 191 ± 36 months (16 ± 3 years). Using a forward stepwise selection (binary regression), the most important prognostic factors were selected, on the basis of which the predictive model “Risk Assessment Algorithm for Recurrence of Breast Carcinoma” was constructed.Results. During the study period, recurrence of stage I breast cancer was reported in 67 patients, representing 17.4 % of the total cohort. Five prognostic factors were selected by binary regression: grade, histological type, estrogen receptor expression, HER2 / neu overexpression and Ki-67 amplification. Kaplan–Meier analysis and Cox proportional hazards method demonstrated the influence of each of the selected factors on disease-free survival. Comparative analysis with other existing models showed that our prognostic model is inferior to Adjuvant! Online in terms of sensitivity (85 % ver- sus 95 %). However, it is superior in specificity (58 % versus 38 %), PPV (69 % versus 63 %) and AUC (84 % versus 70 %).Conclusions. In I stage breast cancer, factors such as grade, histological type, estrogen receptor expression, HER2 / neu overexpression and Ki-67 amplification are the most significant predictive factors influencing recurrence rates. The algorithm for assessing the risk of recurrence of stage I breast cancer can predict the risk of tumour progression with a sensitivity of 84 % and a specificity of 58 % (p <0.05).


2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Camila P. Villavicencio ◽  
Harriet Windley ◽  
Pietro B. D’Amelio ◽  
Manfred Gahr ◽  
Wolfgang Goymann ◽  
...  

Abstract Background The connection between testosterone and territoriality in free-living songbirds has been well studied in a reproductive context, but less so outside the breeding season. To assess the effects of seasonal androgenic action on territorial behavior, we analyzed vocal and non-vocal territorial behavior in response to simulated territorial intrusions (STIs) during three life-cycle stages in free-living male black redstarts: breeding, molt and nonbreeding. Concurrently, we measured changes in circulating testosterone levels, as well as the mRNA expression of androgen and estrogen receptors and aromatase in the preoptic, hypothalamic and song control brain areas that are associated with social and vocal behaviors. Results Territorial behavior and estrogen receptor expression in hypothalamic areas did not differ between stages. But plasma testosterone was higher during breeding than during the other stages, similar to androgen receptor and aromatase expression in the preoptic area. The expression of androgen receptors in the song control nucleus HVC was lower during molt when birds do not sing or sing rarely, but similar between the breeding and the nonbreeding stage. Nevertheless, some song spectral features and the song repertoire differed between breeding and nonbreeding. Territorial behavior and song rate correlated with the expression of steroid receptors in hypothalamic areas, and in the song control nucleus lMAN. Conclusions Our results demonstrate seasonal modulation of song, circulating testosterone levels, and brain sensitivity to androgens, but a year-round persistency of territorial behavior and estrogen receptor expression in all life-cycle stages. This suggests that seasonal variations in circulating testosterone concentrations and brain sensitivity to androgens is widely uncoupled from territorial behavior and song activity but might still affect song pattern. Our study contributes to the understanding of the complex comparative neuroendocrinology of song birds in the wild.


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