Evaluating the Impact of the COVID-19 Pandemic on First-Year Medical Student Nutrition.

BACKGROUND: Medical school students in high-stress environments have been shown to make poor personal health decisions ranging from less healthy selections of food to lower rates of exercise. With the emergence of the COVID-19 pandemic adding a major social and health challenge, it is important to examine the effect this new stressor has on the health habits of medical school students. METHODS: All first-year students at Albany Medical College completed a self-recorded three-day log of food intake and exercise modality and duration. Reported data included calories, carbohydrates, protein, lipids, sodium, calcium, and other micronutrients. The data was divided between pre-pandemic (2018-19) and mid-pandemic (2020-21) entries. T-tests and ANOVA tests were used to compare for significance. RESULTS: Students consumed significantly fewer calories during the pandemic compared to before. This reduction was primarily driven by the female cohort of students. Specifically, this reduction in calories appears to be driven by a decrease in carbohydrate consumption, rather than lipids or protein, which did not change. Additionally, there were significant decreases in sodium, calcium, and vitamin D intake. The mid-pandemic time span (2020-21) appears to be correlated with decreased caloric intake, as well as other important nutrients such as vitamin D and calcium. CONCLUSIONS: This study demonstrated a decrease in calories, carbohydrates, sodium, and alcohol consumption when comparing pre- and mid-pandemic dietary habits of first-year medical students. It also indicated less than the recommended amount of calcium and Vitamin D consumption. Such changes may indicate restrictive eating habits in times of stress.

Intralabial Lip Compartments and their Potential Clinical Relevance.

BACKGROUND: Aesthetic soft tissue filler injections for lip enhancement are highly popular and are performed throughout the world. When injecting lips with cannulas, as the cannula is advanced, resistance is perceived in consistent locations potentially indicating boundaries between intralabial compartments. OBJECTIVE: To investigate whether intra-labial compartments exist and (if so) to describe their volumes, location, boundaries, and dimensions. METHODS: This cadaveric study investigated a total of n = 20 (13 males, 7 females) human body donors with a mean age at death of 61.9 (23.9) years and a mean body mass index of 24.3 (3.7) kg/m 2. The investigated cohort included n = 11 Caucasian, n = 8 Asian, and n = 1 African American donors. Dye injections simulating minimally invasive lip treatments were conducted. RESULTS: Independent of gender or race, 6 anterior and 6 posterior compartments in the upper and lower lip were identified, for a total of 24 lip compartments. Compartment boundaries were formed by vertically oriented septations that were found in consistent locations. The anterior compartments had volumes ranging from 0.30 - 0.39 cc whereas the posterior compartment volume ranged from 0.44 - 0.52 cc. Centrally, the compartment volumes were larger and decreased gradually towards the oral commissure. CONCLUSION: The volume and the size of each of the 24 compartments contribute to the overall appearance and shape of the lips. To achieve a natural and lip-shape preserving aesthetic outcome it may be preferable to administer the volumizing product using a compartment-respecting injection approach.

Precision in Midfacial Volumization Using Ultrasound-Assisted Cannula Injections.

BACKGROUND: Soft-tissue filler injections performed with a cannula are perceived to be less precise because of the length of the instrument and the blunt tip, which can deviate in any direction. Midfacial needle injections are favored despite the increased risk for intraarterial product placement. The objective of this study was to demonstrate that ultrasound-assisted cannula injections of the midface result in precise, safe, and effective volumization procedures. METHODS: Midfacial injections with a 22-G cannula were performed in 188 midfaces of 94 healthy volunteers [86 women; age, 53.05 (9.9) years; 23.63 (2.1) kg/m 2 ] under ultrasound-assisted guidance. Precision (ie, administration of product in the same plane as the location of the cannula tip), safety (ie, rate of adverse events), and aesthetic outcome (rated by the patient and the treating physician) were assessed. RESULTS: In 100% of cases, the product was applied into the desired deep midfacial fat compartment, and the product did not migrate into more superficial layers during the injection process or at any follow-up visit. There was a statistically significant ( P < 0.001) improvement in midfacial volume loss and the aesthetic outcome was rated as very much improved. No adverse events were reported throughout follow-up. CONCLUSIONS: Real-time imaging allows for visual feedback during cannula advancement and injection procedures in the midface and can help practitioners achieve safer aesthetic outcomes. It is hoped that practitioners decide to use a cannula more frequently for midfacial volumization, given the results presented in this article. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

The mobility of the superficial and deep midfacial fat compartments: An ultrasound-based investigation.

BACKGROUND: Understanding the mobility of the midface and the separate contributions of the superficial and deep fat compartments is essential for natural esthetic outcomes following soft tissue filler or fat grafting procedures. A study was designed that used ultrasound imaging to demonstrate in vivo visualization and quantification of distances and movements in the midface. METHODS: A total of 48 midfaces of 24 healthy Caucasian volunteers, all naïve of esthetic procedures, (22 females; 46.85 (9.8) years; 22.83 (3.1) kg/m2 ) were scanned using 18 MHz ultrasound imaging. Distances between bony landmarks (inferior orbital rim, infraorbital foramen) were used as markers to measure the cranial movement of the superficial (superficial nasolabial and superficial medial cheek fat compartment) and the deep (deep pyriform space, deep medial check fat compartment, deep lateral cheek fat compartment) midfacial fat compartments between resting and smiling facial position. RESULTS: The superficial midfacial fat compartment moved, on average, 3.7 mm (p < 0.001) cranially, whereas the deep midfacial fat compartments moved, on average, 0.1 mm (p > 0.05) during smiling. No gender differences in mobility were identified (p > 0.05). CONCLUSION: The results obtained are in line with previous cadaveric investigations and revealed, in a highly statistically significant fashion, that the superficial midfacial fat compartments move in cranial direction whereas the deep fat compartment did not display similar positional changes. These results help to guide facial injectable treatments and to understand why, in the midface, a deep supraperiosteal approach should be favored when augmenting the deep midfacial fat compartments.

Can smiling influence the blood flow in the facial vein?-An experimental study.

BACKGROUND: The understanding of functional facial anatomy and the interplay between facial structures is crucial for safe and effective minimally invasive and cosmetic surgical procedures. AIM: In this experimental study, we investigate the hypothesis that smiling can alter the blood flow in the angular/facial vein. MATERIALS AND METHODS: Twenty-six observations from 15 healthy volunteers (6 men, 9 women) with a mean age of 50.53 ± 13.27 (range: 24-66) were obtained. Doppler ultrasound imaging of the infraorbital segment of the angular vein (cranial to the zygomaticus major muscle) was performed and the venous flow was measured in a smiling and a resting, nonsmiling facial position. RESULTS: A statistically significant change in venous blood flow was detected upon smiling: a reduction in flow from 6.12 ± 3.0 cm/s to 0.52 ± 1.3 cm/s (P = .001). After three seconds, 80.8% of the observations had a blood flow of 0.0 cm/s. Increasing age was significantly correlated with a persistent blood flow during smiling (rp  = .469; P = .016). No differences between gender and sides of the face were observed. CONCLUSION: The results of this experimental study reveal that smiling can significantly reduce the venous flow in the angular/facial vein. Contraction of the zygomaticus major muscle compresses the vein against the underlying maxilla. Both minimally invasive and surgical procedures that alter the SMAS, the periocular musculature or the deep midfacial fat compartments might affect angular/facial venous flow.

VCAM1 is essential to maintain the structure of the SVZ niche and acts as an environmental sensor to regulate SVZ lineage progression.

Neurons arise in the adult forebrain subventricular zone (SVZ) from Type B neural stem cells (NSCs), raising considerable interest in the molecules that maintain this life-long neurogenic niche. Type B cells are anchored by specialized apical endfeet in the center of a pinwheel of ependymal cells. Here we show that the apical endfeet express high levels of the adhesion and signaling molecule vascular cell adhesion molecule-1 (VCAM1). Disruption of VCAM1 in vivo causes loss of the pinwheels, disrupted SVZ cytoarchitecture, proliferation and depletion of the normally quiescent apical Type B cells, and increased neurogenesis in the olfactory bulb, demonstrating a key role in niche structure and function. We show that VCAM1 signals via NOX2 production of reactive oxygen species (ROS) to maintain NSCs. VCAM1 on Type B cells is increased by IL-1ß, demonstrating that it can act as an environmental sensor, responding to chemokines involved in tissue repair.

The effect of long-term release of Shh from implanted biodegradable microspheres on recovery from spinal cord injury in mice.

After spinal cord injury (SCI), loss of cells and damage to ascending and descending tracts can result in paralysis. Current treatments for SCI are based on patient stabilization, and much-needed regenerative therapies are still under development. To activate and instruct stem and progenitor cells or injured tissue to aid SCI repair, it is important to modify the injury environment for a protracted period, to allow time for cell activation, proliferation and appropriate fate differentiation. Shh plays a critical role in spinal cord formation, being involved in multiple processes: it promotes production of motor neurons and oligodendrocytes from ventral cord progenitor cells and serves as an axon guidance molecule. Hence Shh is a candidate pleiotropic beneficial environmental factor for spinal cord regeneration. Here we show that administration of biodegradable microspheres that provide sustained, controlled delivery of Shh resulted in significant functional improvement in two different mouse models of SCI: contusion and dorsal hemioversection. The mechanism is multifactorial, involving increased proliferation of endogenous NG2+ oligodendrocyte lineage cells, decreased astrocytic scar formation and increased sprouting and growth of corticospinal (CST) and raphespinal tract (RST) fibers. Thus, long-term administration of Shh is a potential valuable therapeutic intervention for SCI.

Bmi-1 cooperates with Foxg1 to maintain neural stem cell self-renewal in the forebrain.

Neural stem cells (NSCs) persist throughout life in two forebrain areas: the subventricular zone (SVZ) and the hippocampus. Why forebrain NSCs self-renew more extensively than those from other regions remains unclear. Prior studies have shown that the polycomb factor Bmi-1 is necessary for NSC self-renewal and that it represses the cell cycle inhibitors p16, p19, and p21. Here we show that overexpression of Bmi-1 enhances self-renewal of forebrain NSCs significantly more than those derived from spinal cord, demonstrating a regional difference in responsiveness. We show that forebrain NSCs require the forebrain-specific transcription factor Foxg1 for Bmi-1-dependent self-renewal, and that repression of p21 is a focus of this interaction. Bmi-1 enhancement of NSC self-renewal is significantly greater with increasing age and passage. Importantly, when Bmi-1 is overexpressed in cultured adult forebrain NSCs, they expand dramatically and continue to make neurons even after multiple passages, when control NSCs have become restricted to glial differentiation. Together these findings demonstrate the importance of Bmi-1 and Foxg1 cooperation to maintenance of NSC multipotency and self-renewal, and establish a useful method for generating abundant forebrain neurons ex vivo, outside the neurogenic niche.

Identifying the perpetrator in medulloblastoma: Dorian Gray versus Benjamin Button.

Tumors contain a subpopulation of tumor-propagating cells (TPCs) that are critical for their growth. In this issue, Read, Wechsler-Reya, and colleagues show that in an animal model of medulloblastoma, TPCs express the surface marker CD15 and have properties distinct from neural stem cells.

Multipotent embryonic spinal cord stem cells expanded by endothelial factors and Shh/RA promote functional recovery after spinal cord injury.

Cell transplantation is a promising way to treat spinal cord injury and neurodegenerative disorders. Neural stem cells taken from the embryonic spinal cord are an appealing source of cells for transplantation because these cells are committed to making spinal cord progeny. However these stem cells are rare and require expansion in tissue culture to generate sufficient cells for transplantation. We have developed a novel method for expanding embryonic mouse spinal cord stem cells using a co-culture system with endothelial cells. This method improves neural stem cell survival and preserves their multipotency, including their ability to make motor neurons. Transplantation of endothelial-expanded neural stem cells that were treated with sonic hedgehog(Shh) and retinoic acid (RA) during the expansion phase, into an adult mouse SCI model resulted in significant recovery of sensory and motor function.

shRNA knockdown of Bmi-1 reveals a critical role for p21-Rb pathway in NSC self-renewal during development.

Knockout studies have shown that the polycomb gene Bmi-1 is important for postnatal, but not embryonic, neural stem cell (NSC) self-renewal and have identified the cell-cycle inhibitors p16/p19 as molecular targets. Here, using lentiviral-delivered shRNAs in vitro and in vivo, we determined that Bmi-1 is also important for NSC self-renewal in the embryo. We found that neural progenitors depend increasingly on Bmi-1 for proliferation as development proceeds from embryonic through adult stages. Acute shRNA-mediated Bmi-1 reduction causes defects in embryonic and adult NSC proliferation and self-renewal that, unexpectedly, are mediated by a different cell-cycle inhibitor, p21. Gene array analyses revealed developmental differences in Bmi-1-controlled expression of genes in the p21-Rb cell cycle regulatory pathway. Our data therefore implicate p21 as an important Bmi-1 target in NSCs, potentially with stage-related differences. Understanding stage-related mechanisms underlying NSC self-renewal has important implications for development of stem cell-based therapies.