Morphometric methodologies were developed and applied to investigate the patterns of vascular development in maternal (caruncular; CAR) and fetal (cotyledonary; COT) sheep placentas throughout the last two thirds of gestation. We also examined the expression levels of the major angiogenic factors and their receptors in CAR and COT sheep placentas. Although the vascularity of the CAR tissues increased continuously from Day 50 through Day 140 of pregnancy, those of the COT tissues increased at about twice the instantaneous rate (i.e., the proportionate increase/day) of the CAR. For CAR, vascularity increased 2-fold from Day 50 through Day 140 via relatively small increases in capillary number and 2- to 3-fold increases in capillary diameter. For COT, the increased vascularity resulted from a 12-fold increase in capillary number associated with a concomitant 2-fold decrease in capillary diameter. This large increase in fetal placental capillary number, which was due to increased branching, resulted in 6-fold increases in total capillary cross-sectional area and total capillary surface, per unit of COT tissue. Different patterns of expression of the mRNAs for angiogenic factors and their receptors were observed for CAR and COT. The dilation-like angiogenesis of CAR was correlated with the expression of vascular endothelial growth factor receptor-1 (FLT1), angiopoietin-2 (ANGPT2), and soluble guanylate cyclase (GUCY1B3) mRNAs. The branching-like angiogenesis of COT was correlated with the expression of vascular endothelial growth factor (VEGF), FLT1, angiopoietin-1 (ANGPT1), ANGPT2, and FGF2 mRNAs. Monitoring the expression of angiogenic factors and correlating the levels with quantitative measures of vascularity enable one to model angiogenesis in a spatiotemporal fashion.
There is little debate that the health workforce is a key component of the health care system. Since the training of doctors and nurses takes several years, and the building of new schools even longer, projections are needed to allow for the development of health workforce policies. Our work develops a projection model for the demand of doctors and nurses by Organisation for Economic Co-operation and Development (OECD) countries in the year 2030. The model is based on a country's demand for health services, which includes the following factors: per capita income, out-of-pocket health expenditures and the ageing of its population. The supply of doctors and nurses is projected using country-specific autoregressive integrated moving average models. Our work shows how dramatic imbalances in the number of doctors and nurses will be in OECD countries should current trends continue. For each country in the OECD with sufficient data, we report its demand, supply and shortage or surplus of doctors and nurses for 2030. We project a shortage of nearly 400,000 doctors across 32 OECD countries and shortage of nearly 2.5 million nurses across 23 OECD countries in 2030. We discuss the results and suggest policies that address the shortages.
BackgroundThe High-Level Commission on Health Employment and Economic Growth released its report to the United Nations Secretary-General in September 2016. It makes important recommendations that are based on estimates of over 40 million new health sector jobs by 2030 in mostly high- and middle-income countries and a needs-based shortage of 18 million, mostly in low- and middle-income countries. This paper shows how these key findings were developed, the global policy dilemmas they raise, and relevant policy solutions.MethodsRegression analysis is used to produce estimates of health worker need, demand, and supply. Projections of health worker need, demand, and supply in 2030 are made under the assumption that historical trends continue into the future.ResultsTo deliver essential health services required for the universal health coverage target of the Sustainable Development Goal 3, there will be a need for almost 45 million health workers in 2013 which is projected to reach almost 53 million in 2030 (across 165 countries). This results in a needs-based shortage of almost 17 million in 2013. The demand-based results suggest a projected demand of 80 million health workers by 2030.ConclusionsDemand-based analysis shows that high- and middle-income countries will have the economic capacity to employ tens of millions additional health workers, but they could face shortages due to supply not keeping up with demand. By contrast, low-income countries will face both low demand for and supply of health workers. This means that even if countries are able to produce additional workers to meet the need threshold, they may not be able to employ and retain these workers without considerably higher economic growth, especially in the health sector.
Abnormal placental development limits success in ruminant pregnancies derived from somatic cell nuclear transfer (SCNT), due to reduction in placentome number and consequently, maternal/fetal exchange. In the primary stages of an epithelial-chorial association, the maternal/fetal interface is characterized by progressive endometrial invasion by specialized trophoblast binucleate/giant cells (TGC). We hypothesized that dysfunctional placentation in SCNT pregnancies results from aberration in expression of genes known to be necessary for trophoblast proliferation (Mash2), differentiation (Hand1), and function (IFN-t and PAG-9). We, therefore, compared the expression of these factors in trophoblast from bovine embryos derived from artificial insemination (AI), in vitro fertilization (IVF), and SCNT prior to (day 17) and following (day 40 of gestation) implantation, as well as TGC densities and function. In preimplantation embryos, Mash2 mRNA was more abundant in SCNT embryos compared to AI, while Hand1 was highest in AI and IVF relative to SCNT embryos. IFN-t mRNA abundance did not differ among groups. PAG-9 mRNA was undetectable in SCNT embryos, present in IVF embryos and highest in AI embryos. In postimplantation pregnancies, SCNT fetal cotyledons displayed higher Mash2 and Hand1 than AI and IVF tissues. Allelic expression of Mash2 was not different among the groups, which suggests that elevated mRNA expression was not due to altered imprinting status of Mash2. The day 40 SCNT cotyledons had the fewest number of TGC compared to IVF and AI controls. Thus, expression of genes critical to normal placental development is altered in SCNT bovine embryos, and this is expected to cause abnormal trophoblast differentiation and contribute to pregnancy loss.
Female aging entails a decline in fertility in mammals, manifested by reduced oocyte reserves and poor oocyte quality accompanied by chromosomal anomalies and reduced litter size. In addition to compromised genetic integrity, recent studies suggest that epigenetic mechanisms may be altered in aging oocytes, with age affecting the expression of DNA methyltransferases, which catalyze the important epigenetic modification, DNA methylation. Loss of DNA methylation patterns, most notably for imprinted genes, is lethal to mouse embryos. To investigate how maternal age affects embryonic development and underlying DNA methylation patterns, young and aged C57BL/6 females were mated with C57BL/6 or C57BL/6(CAST7) males to allow for the identification of parental alleles; resulting blastocysts and mid-gestation embryos and placentas were evaluated. Although pregnancy, ovulation and implantation rates were similar between age groups, an age-related increase in resorption sites, morphological abnormalities and delayed development was found. Interestingly, placental morphology was also perturbed by aging, with elevated numbers of trophoblast giant cells in aged pregnancies. Normal monoallelic expression of the imprinted genes H19 and Snrpn was unaltered in blastocysts from aged females. We failed to observe any age-related changes in methylation of the differentially methylated regions of imprinted genes Snrpn, Kcnq1ot1, U2af1-rs1, Peg1, Igf2r and H19. Restriction Landmark Genome Scanning showed no significant differences in genome-wide DNA methylation in embryos and placentas, regardless of maternal age. Our findings demonstrate that maternal age affects post-implantation embryo and placental development; however embryos capable of developing to mid-gestation appear to undergo normal acquisition and maintenance of DNA methylation patterning.
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