Gender Disparity in Evaluation of Internal Medicine Clerkship Performance.

Importance: Women studying medicine currently equal men in number, but evidence suggests that men and women might not be evaluated equally throughout their education.

Objective: To examine whether there are differences associated with gender in either objective or subjective evaluations of medical students in an internal medicine clerkship.

Design, Setting, And Participants: This single-center retrospective cohort study evaluated data from 277 third-year medical students completing internal medicine clerkships in the 2017 to 2018 academic year at an academic hospital and its affiliates in Pennsylvania.

Critical Care Utilization and Outcomes of Interhospital Medical Transfers at Lower Risk of Death.

Purpose: To evaluate utilization and mortality outcomes of interhospital transferred critically-ill medical patients with lower predicted risk of hospital mortality.

Materials & Methods: Multisite retrospective cohort analysis of patients with Acute Physiology and Chronic Health Evaluation (APACHE) IV-a predicted mortality of ≤20% from 335 ICUs in 208 hospitals in the Philips eICU database between 2014-2015. Differences in length-of-stay (LOS) and mortality between transferred and local patients were evaluated using negative binomial logistic regression and logistic regression, respectively.

Differential Effect of Long-Term Systemic Exposure of TNFα on Health of the Annulus Fibrosus and Nucleus Pulposus of the Intervertebral Disc.

The inflammatory cytokine tumor necrosis factor alpha (TNFα) is considered to play a key role in the pathogenesis of intervertebral disc disease. To evaluate the importance of this cytokine we examined the inflammatory environment and spinal phenotype of 9-month-old human TNFα overexpressing transgenic (hTNFα-TG) mice. The mice evidenced increased circulating levels of interleukin-1β (IL-1β), IL-2, keratinocyte chemoattractant/human growth-regulated oncogene (KC/GRO), and monocyte chemoattractant protein-1 (MCP-1) along with thinning of the cortical and trabecular vertebral bone.

A New Understanding of the Role of IL-1 in Age-Related Intervertebral Disc Degeneration in a Murine Model.

Increased cytokine expression, in particular interleukin-1β (IL-1β), is considered a hallmark of intervertebral disc degeneration. However, the causative relationship between IL-1 and age-dependent degeneration has not been established. To investigate the role of IL-1 in driving age-related disc degeneration, we studied the spine phenotype of global IL-1α/β double knockout (IL-1KO) mice at 12 and 20 months.

Transgenic mice overexpressing human TNF-α experience early onset spontaneous intervertebral disc herniation in the absence of overt degeneration.

There is a well-established link between cytokine expression and the progression of intervertebral disc degeneration. Among these cytokines, interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) are the most commonly studied. To investigate whether systemic hTNF-α overexpression affects intervertebral disc health, we studied the spine phenotype of Tg197 mice, a widely used hTNF-α transgenic line.

Discovery of the drivers of inflammation induced chronic low back pain: from bacteria to diabetes.

The intervertebral disc is a unique avascular organ that supports axial skeleton flexion and rotation. The high proteoglycan content of the nucleus pulposus tissue, present at the center of the disc, is pivotal for its mechanical function, distribution of compressive loads. Chronic low back pain, a prevalent and costly condition, is strongly associated with disc degeneration.

Hypoxic regulation of functional extracellular matrix elaboration by nucleus pulposus cells in long-term agarose culture.

Degeneration of the intervertebral discs is strongly implicated as a cause of low back pain. Since current treatments for discogenic low back pain show poor long-term efficacy, a number of new biological strategies are being pursued. For such therapies to succeed, it is critical that they be validated in conditions that mimic the unique biochemical microenvironment of the nucleus pulposus (NP), which include low oxygen tension.

In vivo retention and bioactivity of IL-1ra microspheres in the rat intervertebral disc: a preliminary investigation.

Background: Inflammatory cytokines such as interleukin-1 beta (IL-1β) contribute to the progression of intervertebral disc degeneration. Previously we demonstrated, in vitro, that by delivering interleukin-1 receptor antagonist (IL-1ra) from poly(lactic co-glycolic acid) (PLGA) microspheres, we could attenuate the degradative effects of IL-1β on the nucleus pulposus (NP) for up to 20 days. The objective of this study was to undertake a preliminary investigation into whether microspheres could be successfully delivered to and retained in the disc in vivo, and whether IL-1ra released from those microspheres remained biologically active.

In vitro characterization of a stem-cell-seeded triple-interpenetrating-network hydrogel for functional regeneration of the nucleus pulposus.

Intervertebral disc degeneration is implicated as a major cause of low-back pain. There is a pressing need for new regenerative therapies for disc degeneration that restore native tissue structure and mechanical function. To that end we investigated the therapeutic potential of an injectable, triple-interpenetrating-network hydrogel comprised of dextran, chitosan, and teleostean, for functional regeneration of the nucleus pulposus (NP) of the intervertebral disc in a series of biomechanical, cytotoxicity, and tissue engineering studies.

Needle puncture injury causes acute and long-term mechanical deficiency in a mouse model of intervertebral disc degeneration.

Low back pain is a significant socioeconomic burden and intervertebral disc degeneration has been implicated as a cause. A reliable animal model of disc degeneration is necessary to evaluate therapeutics, and functional metrics are essential to quantify their benefit. To this end, needle puncture injuries were created in the caudal intervertebral discs of mice to induce disc degeneration.

Decreased bacteria activity on Si₃N₄ surfaces compared with PEEK or titanium.

A significant need exists for orthopedic implants that can intrinsically resist bacterial colonization. In this study, three biomaterials that are used in spinal implants--titanium (Ti), polyether-ether-ketone (PEEK), and silicon nitride (Si₃N₄)--were tested to understand their respective susceptibility to bacterial infection with Staphylococcus epidermidis, Staphlococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Enterococcus. Specifically, the surface chemistry, wettability, and nanostructured topography of respective biomaterials, and the effects on bacterial biofilm formation, colonization, and growth were investigated.

IL-1ra delivered from poly(lactic-co-glycolic acid) microspheres attenuates IL-1β-mediated degradation of nucleus pulposus in vitro.

Introduction: Inflammation plays a key role in the progression of intervertebral disc degeneration, a condition strongly implicated as a cause of lower back pain. The objective of this study was to investigate the therapeutic potential of poly(lactic-co-glycolic acid) (PLGA) microspheres loaded with interleukin-1 receptor antagonist (IL-1ra) for sustained attenuation of interleukin-1 beta (IL-1β) mediated degradative changes in the nucleus pulposus (NP), using an in vitro model.

Methods: IL-1ra was encapsulated in PLGA microspheres and release kinetics were determined over 35 days.

Silver nanoparticle toxicity in Drosophila: size does matter.

Background: Consumer nanotechnology is a growing industry. Silver nanoparticles are the most common nanomaterial added to commercially available products, so understanding the influence that size has on toxicity is integral to the safe use of these new products. This study examined the influence of silver particle size on Drosophila egg development by comparing the toxicity of both nanoscale and conventional-sized silver particles.