Modern Medicine: Ideas and Advances

Considering the limitations of medical science and the risks associated with medical treatments, we need to re-examine the connotation of medical science from the perspective of philosophy. Medical science is the natural expression of human kindness and human nature of rescuing the dying and healing the wounded. It is a combination of the natural sciences, social sciences, and humanities. From the perspectives of medical philosophy and humanistic care, this article expounds the concepts and ideas of evidence-based, translational, and precision medicine in modern medicine and emphasizes the importance of avoiding new technical bureaucracy, paying attention to achieving a holistic view and systematic understanding, and avoiding biases in development because of the loss of the humanistic spirit in modern medical practice.     

Fate of the Fc fusion protein aflibercept in retinal endothelial cells: competition of recycling and degradation

Graefe's Archive for Clinical and Experimental Ophthalmology - Intravitreal injection of the VEGF-binding protein aflibercept is widely used to treat various ocular diseases. In vitro,...     

HIV infection after prenatal screening: an open window leading to perinatal infection

Despite a dramatic decrease in vertical transmission of HIV in the developed world, maternal HIV infection acquired after negative prenatal screening still leaves a window of vulnerability. Through quality assurance programs in two Canadian Provinces, five cases where perinatal HIV transmission occurred despite negative prenatal screening were identified between 2005 and 2015. Maternal risk factors such as intravenous drug use, high–risk sexual behavior, hepatitis C virus co–infection, and belonging to high prevalence minority groups were common. Two mothers had their negative HIV test performed in the first trimester and three mothers had negative testing in the third trimester. All babies were clinically healthy at delivery with a normal weight. Three babies were tested following subsequent identification of maternal HIV infection and two babies presented with opportunistic infections leading to their diagnoses. The characteristics of these cases suggest that to achieve complete elimination of vertical HIV transmission, selective and innovative clinical management of mothers at high risk for HIV may be required.     

Development of a protocol for maintaining viability while shipping organoid‐derived retinal tissue

Retinal organoid technology enables generation of an inexhaustible supply of three‐dimensional retinal tissue from human pluripotent stem cells (hPSCs) for regenerative medicine applications. The high similarity of organoid‐derived retinal tissue and transplantable human fetal retina provides an opportunity for evaluating and modeling retinal tissue replacement strategies in relevant animal models in the effort to develop a functional retinal patch to restore vision in patients with profound blindness caused by retinal degeneration. Because of the complexity of this very promising approach requiring specialized stem cell and grafting techniques, the tasks of retinal tissue derivation and transplantation are frequently split between geographically distant teams. Delivery of delicate and perishable neural tissue such as retina to the surgical sites requires a reliable shipping protocol and also controlled temperature conditions with damage‐reporting mechanisms in place to prevent transplantation of tissue damaged in transit into expensive animal models. We have developed a robust overnight tissue shipping protocol providing reliable temperature control, live monitoring of the shipment conditions and physical location of the package, and damage reporting at the time of delivery. This allows for shipping of viable (transplantation‐competent) hPSC‐derived retinal tissue over large distances, thus enabling stem cell and surgical teams from different parts of the country to work together and maximize successful engraftment of organoid‐derived retinal tissue. Although this protocol was developed for preclinical in vivo studies in animal models, it is potentially translatable for clinical transplantation in the future and will contribute to developing clinical protocols for restoring vision in patients with retinal degeneration.     

Saturated and Unsaturated Bone Marrow Lipids Have Distinct Effects on Bone Density and Fracture Risk in Older Adults

Greater bone marrow adiposity (BMAT) is associated with lower bone mineral density (BMD) and vertebral fractures; less is known about BMAT composition and bone. We studied BMAT composition and bone outcomes in 465 participants from the Age Gene/Environment Susceptibility (AGES)-Reykjavik study. BMAT saturation and unsaturation, measured with magnetic resonance spectroscopy, were defined as the ratio of saturated (1.3 ppm peak) or unsaturated (5.3 ppm peak) lipid to total marrow contents, respectively. At baseline and follow-up visits, spine and hip BMD were assessed with quantitative computed tomography (QCT) and dual-energy X-ray absorptiometry (DXA) and vertebral fractures were identified with DXA. Incident clinical fractures were identified through medical records for up to 8.8 years of follow-up. Associations between BMAT composition and BMD, bone loss, and fractures were evaluated in adjusted regression models. At baseline, mean ± standard deviation (SD) participant age was 81.7 ± 4.3 years, mean BMAT unsaturation was 3.5% ± 1.0%, and mean saturation was 46.3% ± 7.2% in the full cohort (47.7% women). Each SD increase in BMAT saturation was associated with lower trabecular BMD: −23.6% (spine) and −13.0% (total hip) (all p < 0.0001). Conversely, BMAT unsaturation (per SD increase) was associated with higher trabecular BMD: +17.5% (spine) and +11.5% (total hip) (all p < 0.001). BMAT saturation (per SD increase) was associated with greater risk for prevalent (odds ratio [OR] 1.46; 95% confidence interval [CI], 1.11–1.92) and incident (OR 1.55; 95% CI, 1.03–2.34) vertebral fracture. BMAT unsaturation (per SD increase) was associated with lower risk for incident vertebral fracture (OR 0.58; 95% CI, 0.38–0.89). In gender stratified analyses, BMAT saturation and unsaturation had opposite associations with incident clinical fracture among men. In general, saturated marrow lipids were associated with worse skeletal outcomes, whereas unsaturated lipids were associated with better outcomes. We recommend that future studies of marrow fat and skeletal health report measurements of saturated and unsaturated marrow lipids, rather than total marrow fat content alone. © 2022 American Society for Bone and Mineral Research (ASBMR).