Stimulatory effect of gonadotropins on the synthesis of adenosine 3′ :5′-cyclic monophosphate and progesterone by suspensions of rat ovarian interstitial cells

A cell suspension was prepared from immature rat ovaries by treatment with trypsin and collagenase. The isolated cells were capable of converting [8-¹⁴C]adenine to cyclic [¹⁴C]AMP and the rate of this conversion was stimulated in vitro by luteinizing hormone and human chorionic gonadotropine, but not by prolactin, norepinephrine, dopamine or albumin. The accumulation of progesterone was also measured in these cells by radioimmunoassay. In vitro addition of luteinizing hormone stimulated the accumulation of radioimmunoassayable progesterone. The conversion of [8-¹⁴C]adenine to cyclic [¹⁴C]AMP showed a rapid increase during the first 30 min of the incubation period when luteinizing hormone was added to the incubation medium. Progesterone accumulation in response to the same dose of luteinizing hormone showed a lag period for the first 30 min of incubation after which there was an increase up to 2 h. The luteinizing hormone-induced progesterone accumulation was sensitive to puromycin, but there was no effect on the luteinizing hormone-induced increase in cyclic [¹⁴C]AMP formation from [8-¹⁴C]-adenine. Actinomycin D also inhibited the luteinizing hormone-induced progesterone accumulation, with no effect on cyclic AMP formation. The results suggest that the luteinizing hormone-induced progesterone accumulation in rat ovarian interstitial cell suspension is preceded by an increased accumulation of cyclic AMP and that the accumulation of steroid under the influence of luteinizing hormone involve processes sensitive to puromycin and antinomycin D.     

Desensitization to ATP-Mg inhibition of 3-hydroxy-3-methylglutarylCoA reductase by heat treatment of microsomes

HMGCoA reductase is found to be inhibited by palmitylCoA and free CoA. The inhibition of this enzyme by ATP-Mg, but not by palmityl CoA, is lost on preincubation of microsomes at 50°C for 15 min.     

Endogenous Purification Reveals GREB1 as a Key Estrogen Receptor Regulatory Factor

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Highlights? A proteomic method identifies protein-protein interaction in primary tumors ? GREB1 is the top estrogen-induced ER-interacting protein ? GREB1 is an essential ER cofactor recruited to chromatin ? GREB1 is an independent prognostic marker     

Long-Term Secondary Care Costs of Endometrial Cancer: A Prospective Cohort Study Nested within the United Kingdom Collaborative Trial of Ovarian Cancer Screening (UKCTOCS)

BackgroundThere is limited evidence on the costs of Endometrial Cancer (EC) by stage of disease. We estimated the long-term secondary care costs of EC according to stage at diagnosis in an English population-based cohort.MethodsWomen participating in UKCTOCS and diagnosed with EC following enrolment (2001–2005) and prior to 31^st Dec 2009 were identified to have EC through multiple sources. Survival was calculated through data linkage to death registry. Costs estimates were derived from hospital records accessed from Hospital Episode Statistics (HES) with additional patient level covariates derived from case notes and patient questionnaires. Missing and censored data was imputed using Multiple Imputation. Regression analysis of cost and survival was undertaken.Results491 of 641 women with EC were included. Five year total costs were strongly dependent on stage, ranging from £9,475 (diagnosis at stage IA/IB) to £26,080 (diagnosis at stage III). Stage, grade and BMI were the strongest predictors of costs. The majority of costs for stage I/II EC were incurred in the first six months after diagnosis while for stage III / IV considerable costs accrued after the first six months.ConclusionsIn addition to survival advantages, there are significant cost savings if patients with EC are detected earlier.     

Supply- and Demand-Side Factors Influencing Utilization of Infant and Young Child Feeding Counselling Services in Viet Nam

Adequate utilization of services is critical to maximize the impact of counselling on infant and young child feeding (IYCF), but little is known about factors affecting utilization. Our study examined supply- and demand-side factors associated with the utilization of IYCF counselling services in Viet Nam. We used survey data from mothers with children <2y (n = 1,008) and health staff (n = 60) from the evaluation of a program that embedded IYCF counseling into the existing government health system. The frequency of never users, one-time users, repeat users, and achievers of the recommended minimum number of visits at health facilities were 45.1%, 13.0%, 28.4% and 13.5%, respectively. Poisson regression showed that demand-generation strategies, especially invitation cards, were the key factors determining one-time use (Prevalence ratio, PR 3.0, 95% CI: 2.2–4.2), repeated use (PR 3.2, 95% CI: 2.4–4.2), and achievement of minimum visits (PR 5.5, 95% CI: 3.6–8.4). Higher maternal education was associated with higher utilization both for one-time and repeated use. Being a farmer, belonging to an ethnic minority, and having a wasted child were associated with greater likelihood of achieving the minimum recommended number of visits, whereas child stunting or illness were not. Distance to health center was a barrier to repeated visits. Among supply-side factors, good counselling skills (PR: 1.3–1.8) was the most important factor associated with any service use, whereas longer employment duration and greater work pressure of health center staff were associated with lower utilization. Population attributable risk estimations showed that an additional 25% of the population would have achieved the minimum number of visits if exposed to three demand-generation strategies, and further increased to 49% if the health staff had good counseling skills and low work pressure. Our study provides evidence that demand-generation strategies are essential to increase utilization of facility-based IYCF counselling services in Viet Nam, and may be relevant for increasing and sustaining use of nutrition services in similar contexts.     

DYRK1A regulates the recruitment of 53BP1 to the sites of DNA damage in part through interaction with RNF169

Human Dual-specificity tyrosine (Y) Regulated Kinase 1A (DYRK1A) is encoded by a dosage dependent gene whereby either trisomy or haploinsufficiency result in developmental abnormalities. However, the function and regulation of this important protein kinase are not fully understood. Here, we report proteomic analysis of DYRK1A in human cells that revealed a novel role of DYRK1A in DNA double-strand breaks (DSBs) repair, mediated in part by its interaction with the ubiquitin-binding protein RNF169 that accumulates at the DSB sites and promotes homologous recombination repair (HRR) by displacing 53BP1, a key mediator of non-homologous end joining (NHEJ). We found that overexpression of active, but not the kinase inactive DYRK1A in U-2 OS cells inhibits accumulation of 53BP1 at the DSB sites in the RNF169-dependent manner. DYRK1A phosphorylates RNF169 at two sites that influence its ability to displace 53BP1 from the DSBs. Although DYRK1A is not required for the recruitment of RNF169 to the DSB sites and 53BP1 displacement, inhibition of DYRK1A or mutation of the DYRK1A phosphorylation sites in RNF169 decreases its ability to block accumulation of 53BP1 at the DSB sites. Interestingly, CRISPR-Cas9 knockout of DYRK1A in human and mouse cells also diminished the 53BP1 DSB recruitment in a manner that did not require RNF169, suggesting that dosage of DYRK1A can influence the DNA repair processes through both RNF169-dependent and independent mechanisms. Human U-2 OS cells devoid of DYRK1A display an increased HRR efficiency and resistance to DNA damage, therefore our findings implicate DYRK1A in the DNA repair processes.     

Efficient Pre-mRNA Cleavage Prevents Replication-Stress-Associated Genome Instability

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Rethinking Opsins

Opsins, the protein moieties of animal visual photo-pigments, have emerged as moonlighting proteins with diverse, light-dependent and -independent physiological functions. This raises the need to revise some basic assumptions concerning opsin expression, structure, classification, and evolution.