The state of anatomical donation programs amidst the SARS-CoV-2 (Covid-19) pandemic.

The inclusion of human body dissection in anatomical science curricula has been described as a critical educational experience for the mastery of anatomical structures and concepts. To ensure that body donors are ethically acquired and suitable for anatomy education, Anatomical Donation Programs (ADPs) are tasked with the responsibility of acquiring body donors for basic and clinical science curricula. Considering the personal and institutional impact of SARS-CoV-2, a national survey was conducted to examine the current effect of the pandemic on ADP protocols, body donation, and the sustainability of ADPs in the United States (U.S.). Eighty-nine U.S. ADPs were identified and contacted for optional participation in a survey to assess the impact of the SARS-CoV-2 pandemic on their programs. Survey data were collected and managed using REDCap electronic data capture tools. Thirty-six ADPs (40.5% response rate) from the nine U.S. Divisions are represented in the survey results. Data were collected on ADP descriptions and demographics, SARS-CoV-2 impact on ADPs and protocols, and body donation and ADP sustainability. Almost all ADPs reported that the pandemic has affected their ADP operations in some way; however, the sustainability for the majority of ADPs appears likely and donor availability remains stable due to a proportional decrease in body donations and body donor requests. As the long-term impact on ADPs has yet to be determined, the authors plan to reevaluate the lasting impact of the SARS-CoV-2 pandemic on body donation, ADP sustainability, and anatomical science education throughout the year 2021.

Homocysteine inhibits extra-embryonic vascular development in the avian embryo.

A strong association exists between pregnancy loss and maternal elevations of the sulfur-containing amino acid, homocysteine. Because extra-embryonic vascular growth is critical to maintaining a normal pregnancy, we examined the effects of homocysteine on vessel development by exposing avian embryos to exogenous homocysteine during critical periods of vascular growth. These experiments demonstrated that homocysteine significantly reduced survival and decreased angiogenesis in the extra-embryonic vasculature. Homocysteine was also found to reduce mRNA and protein expression of vascular endothelial growth factor (VEGF), a key molecule for vascular development. Moreover, in cultured human umbilical vein endothelial cells, homocysteine increased the synthesis of nitric oxide, an important regulatory molecule for VEGF. Inhibiting the homocysteine-induced up-regulation of nitric oxide restored normal VEGF expression and vascular development. These results suggest that homocysteine may impair the development of the extra-embryonic vasculature by reducing the expression of VEGF.

Role of actin polymerization in bending of the early heart tube.

During cardiac c-looping, the heart transforms from a straight tube into a c-shaped tube, presenting the first evidence of left-right asymmetry in the embryo. C-looping consists of two primary deformation components: ventral bending and dextral rotation. This study examines the role of actin polymerization in bending of the heart tube. Exposure of stage 9-11 chick embryos to low concentrations of the actin polymerization inhibitors cytochalasin D (5 nM-2.0 microM) and latrunculin A (LA; 25 nM-2.0 microM) suppressed looping in a stage- and concentration-dependent manner in both whole embryos and isolated hearts. Local exposure of either the dorsal or ventral sides of isolated hearts to LA also inhibited looping, but less than global exposure, indicating that both sides contribute to the bending mechanism. Taken together, these data suggest that ongoing actin polymerization is required for the bending component of cardiac c-looping, and we speculate that polymerization-driven myocardial cell shape changes cause this deformation.