Gelatin Methacrylate Hydrogels as Biomimetic Three-Dimensional Matrixes for Modeling Breast Cancer Invasion and Chemoresponse in Vitro.

Recent studies have shown that three-dimensional (3D) culture environments allow the study of cellular responses in a setting that more closely resembles the in vivo milieu. In this context, hydrogels have become popular scaffold options for the 3D cell culture. Because the mechanical and biochemical properties of culture matrixes influence crucial cell behavior, selecting a suitable matrix for replicating in vivo cellular phenotype in vitro is essential for understanding disease progression.

Cancer stem cell mediated acquired chemoresistance in head and neck cancer can be abrogated by aldehyde dehydrogenase 1 A1 inhibition.

Chemoresistance leading to disease relapse is one of the major challenges to improve outcome in head and neck cancers. Cancer Stem Cells (CSCs) are increasingly being implicated in chemotherapy resistance, this study investigates the correlation between CSC behavior and acquired drug resistance in in vitro cell line models. Cell lines resistant to Cisplatin (Cal-27 CisR, Hep-2 CisR) and 5FU (Cal-27 5FUR) with high Resistance Indices (RI) were generated (RI ≥ 3) by short-term treatment of head and neck squamous cell carcinoma (HNSCC) cell lines with chemotherapeutic drugs (Cisplatin, Docetaxel, 5FU), using a dose-incremental strategy.

Early alterations in ovarian surface epithelial cells and induction of ovarian epithelial tumors triggered by loss of FSH receptor.

Little is known about the behavior of the ovarian surface epithelium (OSE), which plays a central role in ovarian cancer etiology. It has been suggested that incessant ovulation causes OSE changes leading to transformation and that high gonadotropin levels during postmenopause activate OSE receptors, inducing proliferation. We examined the chronology of OSE changes, including tumor appearance, in a mouse model where ovulation never occurs due to deletion of follitropin receptor.

The relationship between secretory patterns of gonadotrophic hormones and the attainment of puberty in bull and heifer calves born early or late during the spring calving season.

It was suggested that an early increase in gonadotrophin secretion in calves aged between 6 and 24 weeks might be critical for initiating developmental changes culminating in puberty. An early rise in luteinizing hormone (LH) release appears to be caused by an increase in LH pulse frequency in bull calves and by an increase in LH pulse amplitude in heifer calves. Previously we have found differences in the characteristics of the LH rise between prepubertal beef calves born in spring or fall; however, age at puberty was not affected by season of birth.

Ultrasonographic evaluation of the pre-pubertal development of the reproductive tract in beef heifers.

To study the development of the reproductive tract in heifers, the ovaries, uterus, cervix and vagina were examined by transrectal ultrasonography every 2 weeks, from 2 to 60 weeks after birth. First ovulation occurred at 63.7 +/- 1.

Effects of a 6-day treatment with medroxyprogesterone acetate after prostaglandin F2 alpha-induced luteolysis at midcycle on antral follicular development and ovulation rate in nonprolific Western white-faced ewes.

Medroxyprogesterone acetate (MAP) from intravaginal sponges prolongs the lifespan of large ovarian follicles when administered after prostaglandin F2alpha (PGF2alpha)-induced luteolysis early in the luteal phase of ewes. The present study was designed to determine whether a PGF2alpha/MAP treatment applied at midcycle would alter the pattern of antral follicle growth and increase ovulation rate in nonprolific ewes. A single injection of PGF2alpha (15 mg, i.