Pregnancy failure during placentation in lactating dairy cows was associated with low concentrations of serum progesterone. Beef cows have greater serum progesterone and less pregnancy failure. Experiment 1 determined that reduction of serum progesterone affected late embryonic/early fetal loss in suckled beef cows. Cows (n=40) received progesterone from two new or used controlled internal drug releasing devices, replaced every 5d, beginning on Day 28 of gestation (mating=Day 0); CL were enucleated on Day 29. Retention of pregnancy was 77% in treated cows and 97% in 78 control cows (P<0.05). Experiment 2 determined how pregnant, lactating dairy cows with high or low progesterone concentrations during Days 28-34 differed in luteal function or in serum progesterone during replacement therapy. Luteal tissue from such cows was assayed for progesterone and expression of mRNA for genes of endothelin and prostaglandin (PG) systems. Secretion of progesterone and prostaglandins by dispersed luteal cells was determined during incubation with LH, endothelin-1, or arachidonic acid. Neither luteal progesterone nor mRNAs for endothelin or prostaglandin systems differed. Endothelin-1 inhibited secretion of progesterone more (P<0.05) in luteal cells from cows with low versus high serum progesterone, when incubated with arachidonic acid. Secretion of prostaglandin F(2)alpha was increased and that of 6-keto-PGF(1)alpha decreased by endothelin-1 in vitro. Serum progesterone during replacement was lower (P<0.05) for cows with low than high serum progesterone at lutectomy. Thus, clearance, more than luteal production, determined peripheral progesterone in pregnant, lactating dairy cows.
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http://dx.doi.org/10.1016/j.theriogenology.2008.07.031 | DOI Listing |
BMC Pregnancy Childbirth
January 2025
Reproductive Center of Shenzhen Zhongshan Obstetrics and Gynecology Hospital Formerly Reproductive Center of Shenzhen Zhongshan Urology Hospital, Shenzhen, Guangdong Province, China.
Objective: To develop a predictive tool in the form of a Nomogram based on the Cox regression model, which incorporates the impact of the length of treatment cycles on the outcome of live birth, to evaluate the probability of infertile couples having a live birth after one or more complete cycles of In Vitro Fertilization (IVF), and to provide patients with a risk assessment that is easy to understand and visualize.
Methods: A retrospective study for establishing a prediction model was conducted in the reproductive center of Shenzhen Zhongshan Obstetrics & Gynecology Hospital (formerly Shenzhen Zhongshan Urology Hospital). A total of 4413 patients who completed ovarian stimulation treatment and reached the trigger were involved.
Nat Commun
January 2025
MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin, 300350, China.
Embryonic and fetal development can be affected during gestation by exposure to xenobiotics that cross the placenta. Liquid crystal monomers (LCMs) are emerging contaminants commonly found in indoor environments; however, whether they can cross the placenta and affect placental development remains unexplored. Here, we develop an evaluation system that integrates human biomonitoring, uterine perfusion in pregnant rats, and placental cells.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
State Key Laboratory of Swine and Poultry Breeding Industry, College of Animal Science, South China Agricultural University, Guangzhou 510642, China; National Engineering Research Center for Breeding Swine Industry, Guangdong Provincial Key Laboratory of Agro-Animal Genomics and Molecular Breeding, South China Agricultural University, Guangzhou 510642, China. Electronic address:
This study investigated the effects of cholic acid (CA) on steroid hormone synthesis and follicular development in mouse ovaries and the regulatory mechanism of CA on the expression of steroidogenesis-related genes in granulosa cells. The mice were divided into control and CA groups, and serum and ovarian samples were collected after 1, 2, and 4 months of treatment, respectively. The results showed that CA treatment for 1, 2, and 4 months reduced ovarian weights, disrupted the estrous cycle, decreased the number of antral follicles and corpora lutea, and lowered the serum levels of progesterone and estradiol.
View Article and Find Full Text PDFMol Biol Rep
January 2025
Department of Clinical Pathology, Faculty of Medicine, Alexandria University, Alexandria, Egypt.
Background: The identification of circulating potential biomarkers may help earlier diagnosis of breast cancer, which is critical for effective treatment and better disease outcomes. We aimed to study the role of circ-FAF1 as a diagnostic biomarker in female breast cancer using peripheral blood samples of these patients, and to investigate the relation between circ-FAF1 and different clinicopathological features of the included patients.
Methods And Results: This case-control study enrolled 60 female breast cancer patients and 60 age-matched healthy control subjects.
Cancer Res
January 2025
Swiss Federal Institute of technology in Lausanne, Lausanne, Vaud, Switzerland.
A recent publication by Bornes and colleagues explored the impact of the estrous cycle on mammary tumor response to neoadjuvant chemotherapy (NAC). Using genetically engineered mouse models, Bornes and colleagues revealed that chemotherapy is less effective when initiated during the diestrus stage compared to during the estrus stage. A number of changes during diestrous were identified that may reduce chemosensitivity of mammary tumors: an increased mesenchymal state of breast cancer cells during diestrous, decreased blood vessel diameters, and higher numbers of macrophages in the tumor microenvironment.
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