The Use of Extracellular Vesicles in Achilles Tendon Repair: A Systematic Review.

Achilles tendon (AT) pathologies are common musculoskeletal conditions that can significantly impair function. Despite various traditional treatments, recovery is often slow and may not restore full functionality. The use of extracellular vesicles (EVs) has emerged as a promising therapeutic option due to their role in cell signaling and tissue regeneration. This systematic review aims to consolidate current in vivo animal study findings on the therapeutic effects of EVs on AT injuries. An extensive literature search was conducted using the PubMed, Scopus, and Embase databases for in vivo animal studies examining the effects of EVs on AT pathologies. The extracted variables included but were not limited to the study design, type of EVs used, administration methods, efficacy of treatment, and proposed therapeutic mechanisms. After screening, 18 studies comprising 800 subjects were included. All but one study reported that EVs augmented wound healing processes in the AT. The most proposed mechanisms through which this occurred were gene regulation of the extracellular matrix (ECM), the enhancement of macrophage polarization, and the delivery of therapeutic microRNAs to the injury site. Further research is warranted to not only explore the therapeutic potential of EVs in the context of AT pathologies, but also to establish protocols for their clinical application.

Does a fibula-sparing approach improve outcomes in tibiotalocalcaneal arthrodesis?

BACKGROUND: Tibiotalocalcaneal (TTC) arthrodesis is considered a salvage procedure for either complex deformity or arthritis about the hindfoot, and can be performed via fibula-resection (FR) or fibula-sparing (FS) approaches. The primary aim of this study was to investigate differences in outcomes in FR versus FS TTC arthrodeses. METHODS: This was a retrospective cohort study reviewing outcomes of TTC arthrodesis at a single institution. Patients who underwent a TTC arthrodesis from 2005 to 2017 and had minimum two-year follow-up were included. Preoperative diagnosis, pre- and post-operative radiographic coronal alignment, fixation methods, and complications were compared between groups. RESULTS: 107 patients (110 ankles) underwent TTC arthrodesis, with a mean age of 57.0 years (sd, 14.0 years). The mean clinical follow-up was 50.7 months (range, 24-146) and mean radiographic follow-up was 45.8 months (range, 6-146 months). Pre-operative diagnoses included arthritis (N = 40), prior non-union (N = 21), Charcot neuro-arthropathy (N = 15), failed total ankle arthroplasty (N = 15) and avascular necrosis of the talus (N = 19). Sixty-nine ankles comprised the FS group and 41 comprised the FR group. There was no significant difference in the non-union rate between groups (29% FR vs 38% FS, p = 0.37), complication rate (59% FR vs 64% FS, p = 0.59), or post-operative coronal standing radiographic alignment (89.6 degrees FR, 90.5 degrees FS, p = 0.26). Logistic regression analyses demonstrated a pre-operative diagnosis of failed TAA was associated with post-operative nonunion (OR:3.41,CI:1.13-11.04,p = 0.03). Pre-operative indication for TTC arthrodesis of arthritis alone was associated with a decreased risk of non-union (OR:0.27,CI:0.11-0.62,p = 0.002). CONCLUSION: TTC arthrodesis is a successful surgical option for complex hindfoot deformity, arthritis, and limb salvage regardless of surgical approach. We did not detect a difference in the union rate, incidence of complications, or coronal plane radiographic alignment in fibula-sparing versus fibula-resection constructs. Patients with a pre-operative indication for surgery of arthritis may be at decreased risk of developing non-union. LEVEL OF EVIDENCE: III - Retrospective cohort study.

Environmental Injustice and Electronic Waste in Ghana: Challenges and Recommendations.

Electronic waste (e-waste) or discarded electronic devices that are unwanted, not working, or have reached their end of life pose significant threats to human and environmental health. This is a major concern in Africa, where the majority of e-waste is discarded. In the year 2021, an estimated 57.4 million metric tons of e-waste were generated worldwide. Globally, COVID-19 lockdowns have contributed to increased e-waste generation. Although Africa generates the least of this waste, the continent has been the dumping ground for e-waste from the developed world. The flow of hazardous waste from the prosperous 'Global North' to the impoverished 'Global South' is termed "toxic colonialism". Agbogbloshie, Ghana, an e-waste hub where about 39% of e-waste was treated, was listed among the top 10 most polluted places in the world. The discard of e-waste in Ghana presents an issue of environmental injustice, defined as the disproportionate exposure of communities of color and low-income communities to pollution, its associated health and environmental effects, and the unequal environmental protection provided through policies. Despite the economic benefits of e-waste, many civilians (low-income earners, settlers, children, and people with minimal education) are exposed to negative health effects due to poverty, lack of education, and weak regulations. We critically examine the existing literature to gather empirical information on e-waste and environmental injustice. Comprehensive policies and regulations are needed to manage e-waste locally and globally.

COVID-19 Neuropathology at Columbia University Irving Medical Center/New York Presbyterian Hospital

Many patients with SARS-CoV-2 infection develop neurological signs and symptoms, though, to date, little evidence exists that primary infection of the brain is a significant contributing factor. We present the clinical, neuropathological, and molecular findings of 41 consecutive patients with SARS-CoV-2 infections who died and underwent autopsy in our medical center. The mean age was 74 years (38-97 years), 27 patients (66%) were male and 34 (83%) were of Hispanic/Latinx ethnicity. Twenty-four patients (59%) were admitted to the intensive care unit (ICU). Hospital-associated complications were common, including 8 (20%) with deep vein thrombosis/pulmonary embolism (DVT/PE), 7 (17%) patients with acute kidney injury requiring dialysis, and 10 (24%) with positive blood cultures during admission. Eight (20%) patients died within 24 hours of hospital admission, while 11 (27%) died more than 4 weeks after hospital admission. Neuropathological examination of 20-30 areas from each brain revealed hypoxic/ischemic changes in all brains, both global and focal; large and small infarcts, many of which appeared hemorrhagic; and microglial activation with microglial nodules accompanied by neuronophagia, most prominently in the brainstem. We observed sparse T lymphocyte accumulation in either perivascular regions or in the brain parenchyma. Many brains contained atherosclerosis of large arteries and arteriolosclerosis, though none had evidence of vasculitis. Eighteen (44%) contained pathologies of neurodegenerative diseases, not unexpected given the age range of our patients. We examined multiple fresh frozen and fixed tissues from 28 brains for the presence of viral RNA and protein, using quantitative reverse-transcriptase PCR (qRT-PCR), RNAscope, and immunocytochemistry with primers, probes, and antibodies directed against the spike and nucleocapsid regions. qRT-PCR revealed low to very low, but detectable, viral RNA levels in the majority of brains, although they were far lower than those in nasal epithelia. RNAscope and immunocytochemistry failed to detect viral RNA or protein in brains. Our findings indicate that the levels of detectable virus in COVID-19 brains are very low and do not correlate with the histopathological alterations. These findings suggest that microglial activation, microglial nodules and neuronophagia, observed in the majority of brains, do not result from direct viral infection of brain parenchyma, but rather likely from systemic inflammation, perhaps with synergistic contribution from hypoxia/ischemia. Further studies are needed to define whether these pathologies, if present in patients who survive COVID-19, might contribute to chronic neurological problems.