Risk of Delayed Percutaneous Coronary Intervention for STEMI in the Southeast United States.

Background: Emergent reperfusion by percutaneous coronary intervention (PCI) within 90 minutes of first medical contact (FMC) is indicated in patients with ST-segment elevation myocardial infarction (STEMI). However, long transport times in rural areas in the Southeast US make meeting this goal difficult. The objective of this study was to determine the number of Southeast US residents with prolonged transport times to the nearest 24/7 primary PCI (PPCI) center. Methods: A cross-sectional study of residents in the Southeastern US was conducted based on geographical and 2022 5-Year American Community Survey data. The geographic information system (GIS) ArcGIS Pro was used to estimate Emergency Medical Services (EMS) transport times for Southeast US residents to the nearest PPCI center. All 24/7 PPCI centers in North Carolina, South Carolina, Georgia, Florida, Mississippi, Alabama, and Tennessee were included in the analysis, as well as nearby PPCI centers in surrounding states. To identify those at risk of delayed FMC-to-device time, the primary outcome was defined as a >30-minute transport time, beyond which most patients would not have PCI within 90 minutes. A secondary outcome was defined as transport >60 minutes, the point at which FMC-to-device time would be >120 minutes most of the time. These cutoffs are based on national median EMS scene times and door-to-device times. Results: Within the Southeast US, we identified 62,880,528 residents and 350 PPCI centers. Nearly 11 million people living in the Southeast US reside greater than 30 minutes from a PPCI center (17.3%, 10,866,710, +/- 58,143), with 2% (1,271,522 +/- 51,858) living greater than 60 minutes from a PPCI hospital. However, most patients reside in short transport zones; 82.7% (52,013,818 +/- 98,741). Within the Southeast region, 8.4% (52/616) of counties have more than 50% of their population in a long transport zone and 42.3% (22/52) of those have more than 90% of their population in long transport areas. Conclusions: Nearly 11 million people in the Southeast US do not have access to timely PCI for STEMI care. This disparity may contribute to increased morbidity and mortality.

Cannabis use in Parkinson's disease: Patient access to medical cannabis and physician perspective on product safety.

The rate of medical cannabis use has increased in parallel with the number of states legalizing its use. Parkinson's disease (PD) patients are of particular concern due to their higher cannabis use rate than in the general US population (25-40 % PD patient cannabis users vs. ∼18 % in the general population), as well as their susceptibility to environmental contaminants in cannabis, including pesticides, toxic elements, solvents, microbes, and mycotoxins. In order to address the complex nature of this industry, we examined the changes in PD-related qualifying conditions in the U.S. from 2019 to 2023. We also conducted an online survey to gain insight into the knowledge, risk perceptions, and opinions regarding medical cannabis and contamination issues from physicians who treated PD patients. The number of states including PD-related qualifying conditions increased over the past 5 years from 28 to 36 states. These conditions included PD (increasing from 14 to 16 states), muscle spasms (14 to 24), anxiety (1 to 5), and pain (17 to 35). State-by-state comparisons revealed high variability in the language used to describe the different qualifying conditions. Online surveys were sent out to 45 neurologists and movement disorder specialists who primarily treated PD patients. The response rate was 44 % from nine states (AZ, CA, FL, MA, MN, WI, PA, IL, and NM). When asked if they were aware of any contaminants in cannabis products, we found that 65 % of the physicians were unaware of any contaminants commonly found in cannabis and only 25 %, 15 %, and 15 % of them were aware of pesticide, toxic element, and solvent contaminants, respectively. In their free-text opinion response on the health impact of cannabis-borne contaminants, "long-term effect" (35 %) and "comorbidities and PD prognosis" (40 %) were identified as the two most common themes. These results point to the need for further regulatory deliberation regarding risks and susceptibility to cannabis contaminants. Additionally, education is needed to inform physicians on cannabis safety issues. Further research will identify the implementation strategies to reduce contaminant exposure and protect patient health.

A systematic review of approaches to assess fish health responses to anthropogenic threats in freshwater ecosystems.

Anthropogenic threats such as water infrastructure, land-use changes, overexploitation of fishes and other biological resources, invasive species and climate change present formidable challenges to freshwater biodiversity. Historically, management of fish and fishery species has largely been based on studies of population- and community-level dynamics; however, the emerging field of conservation physiology promotes the assessment of individual fish health as a key management tool. Fish health is highly sensitive to environmental disturbances and is also a fundamental driver of fitness, with implications for population dynamics such as recruitment and resilience. However, the mechanistic links between particular anthropogenic disturbances and changes in fish health, or impact pathways, are diverse and complex. The diversity of ways in which fish health can be measured also presents a challenge for researchers deciding on methods to employ in studies seeking to understand the impact of these threats. In this review, we aim to provide an understanding of the pathway through which anthropogenic threats in freshwater ecosystems impact fish health and the ways in which fish health components impacted by anthropogenic threats can be assessed. We employ a quantitative systematic approach to a corpus of papers related to fish health in freshwater and utilize a framework that summarizes the impact pathway of anthropogenic threats through environmental alterations and impact mechanisms that cause a response in fish health. We found that land-use changes were the most prolific anthropogenic threat, with a range of different health metrics being suitable for assessing the impact of this threat. Almost all anthropogenic threats impacted fish health through two or more impact pathways. A robust understanding of the impact pathways of anthropogenic threats and the fish health metrics that are sensitive to these threats is crucial for fisheries managers seeking to undertake targeted management of freshwater ecosystems.

Deconvolution and Analysis of the 1H NMR Spectra of Crude Reaction Mixtures.

Nuclear magnetic resonance (NMR) spectroscopy is an important analytical technique in synthetic organic chemistry, but its integration into high-throughput experimentation workflows has been limited by the necessity of manually analyzing the NMR spectra of new chemical entities. Current efforts to automate the analysis of NMR spectra rely on comparisons to databases of reported spectra for known compounds and, therefore, are incompatible with the exploration of new chemical space. By reframing the NMR spectrum of a reaction mixture as a joint probability distribution, we have used Hamiltonian Monte Carlo Markov Chain and density functional theory to fit the predicted NMR spectra to those of crude reaction mixtures. This approach enables the deconvolution and analysis of the spectra of mixtures of compounds without relying on reported spectra. The utility of our approach to analyze crude reaction mixtures is demonstrated with the experimental spectra of reactions that generate a mixture of isomers, such as Wittig olefination and C-H functionalization reactions. The correct identification of compounds in a reaction mixture and their relative concentrations is achieved with a mean absolute error as low as 1%.

Case Report: Taxifolin for neurosurgery-associated early-onset cerebral amyloid angiopathy.

Cases of iatrogenic cerebral amyloid angiopathy (CAA) have been increasingly reported recently, particularly those associated with neurosurgery. Preclinical studies have shown taxifolin to be promising for treating CAA. We describe a young 42-year-old man with a history of childhood traumatic brain injury that required a craniotomy for hematoma evacuation. He later presented with recurrent lobar intracerebral hemorrhage (ICH) decades later, which was histologically confirmed to be CAA. Serial 11C-Pittsburgh compound B positron emission tomography (11C-PiB-PET) imaging showed a 24% decrease in global standardized uptake value ratio (SUVR) at 10 months after taxifolin use. During this period, the patient experienced clinical improvement with improved consciousness and reduced recurrent ICH frequency, which may be partly attributable to the potential amyloid-ß (Aß) clearing the effect of taxifolin. However, this effect seemed to have diminished at 15 months, CAA should be considered in young patients presenting with recurrent lobar ICH with a history of childhood neurosurgery, and serial 11C-PiB-PET scans warrant further validation as a strategy for monitoring treatment response in CAA for candidate Aß-clearing therapeutic agents such as taxifolin.

Assessing Target Specificity of the Small Molecule Inhibitor MARIMASTAT to Snake Venom Toxins: A Novel Application of Thermal Proteome Profiling.

New treatments that circumvent the pitfalls of traditional antivenom therapies are critical to address the problem of snakebite globally. Numerous snake venom toxin inhibitors have shown promising cross-species neutralization of medically significant venom toxins in vivo and in vitro. The development of high-throughput approaches for the screening of such inhibitors could accelerate their identification, testing, and implementation and thus holds exciting potential for improving the treatments and outcomes of snakebite envenomation worldwide. Energetics-based proteomic approaches, including thermal proteome profiling and proteome integral solubility alteration (PISA) assays, represent "deep proteomics" methods for high throughput, proteome-wide identification of drug targets and ligands. In the following study, we apply thermal proteome profiling and PISA methods to characterize the interactions between venom toxin proteoforms in Crotalus atrox (Western Diamondback Rattlesnake) and the snake venom metalloprotease (SVMP) inhibitor marimastat. We investigate its venom proteome-wide effects and characterize its interactions with specific SVMP proteoforms, as well as its potential targeting of non-SVMP venom toxin families. We also compare the performance of PISA thermal window and soluble supernatant with insoluble precipitate using two inhibitor concentrations, providing the first demonstration of the utility of a sensitive high-throughput PISA-based approach to assess the direct targets of small molecule inhibitors for snake venom.

Assessing Heterogeneity in the N-Telopeptides of Type I Collagen by Mass Spectrometry.

Collagen cross-links created by the lysyl oxidase and lysyl hydroxylase families of enzymes are a significant contributing factor to the biomechanical strength and rigidity of tissues, which in turn influence cell signaling and ultimately cell phenotype. In the clinic, the proteolytically liberated N-terminal cross-linked peptide of collagen I (NTX) is used as a biomarker of bone and connective tissue turnover, which is altered in several disease processes. Despite the clinical utility of these collagen breakdown products, the majority of the cross-linked peptide species have not been identified in proteomic datasets. Here we evaluate several parameters for the preparation and identification of these peptides from the collagen I-rich Achilles tendon. Our refined approach involving chemical digestion for protein solubilization coupled with mass spectrometry allows for the identification of the NTX cross-links in a range of modification states. Based on the specificity of the enzymatic cross-linking reaction we utilized follow-up variable modification searches to facilitate identification with a wider range of analytical workflows. We then applied a spectral library approach to identify differences in collagen cross-links in bovine pulmonary hypertension. The presented method offers unique opportunities to understand extracellular matrix remodeling events in development, aging, wound healing, and fibrotic disease that modulate collagen architecture through lysyl-hydroxylase and lysyl-oxidase enzymes.

CASZ1 Is Essential for Skin Epidermal Terminal Differentiation.

The barrier function of skin epidermis is crucial for our bodies to interface with the environment. Because epidermis continuously turns over throughout the lifetime, this barrier must be actively maintained by regeneration. Although several transcription factors have been established as essential activators in epidermal differentiation, it is unclear whether additional factors remain to be identified. In this study, we show that CASZ1, a multi zinc-finger transcription factor previously characterized in nonepithelial cell types, shows highest expression in skin epidermis. CASZ1 expression is upregulated during epidermal terminal differentiation. In addition, CASZ1 expression is impaired in several skin disorders with impaired barrier function, such as atopic dermatitis, psoriasis, and squamous cell carcinoma. Using transcriptome profiling coupled with RNA interference, we identified 674 differentially expressed genes with CASZ1 knockdown. Downregulated genes account for 91.2% of these differentially expressed genes and were enriched for barrier function. In organotypic epidermal regeneration, CASZ1 knockdown promoted proliferation and strongly impaired multiple terminal differentiation markers. Mechanistically, we found that CASZ1 upregulation in differentiation requires the action of both the master transcription factor, p63, and the histone acetyltransferase, p300. Taken together, our findings identify CASZ1 as an essential activator of epidermal differentiation, paving the way for future studies understanding of CASZ1 roles in skin disease.

CoeffNet: predicting activation barriers through a chemically-interpretable, equivariant and physically constrained graph neural network.

Activation barriers of elementary reactions are essential to predict molecular reaction mechanisms and kinetics. However, computing these energy barriers by identifying transition states with electronic structure methods (e.g., density functional theory) can be time-consuming and computationally expensive. In this work, we introduce CoeffNet, an equivariant graph neural network that predicts activation barriers using coefficients of any frontier molecular orbital (such as the highest occupied molecular orbital) of reactant and product complexes as graph node features. We show that using coefficients as features offer several advantages, such as chemical interpretability and physical constraints on the network's behaviour and numerical range. Model outputs are either activation barriers or coefficients of the chosen molecular orbital of the transition state; the latter quantity allows us to interpret the results of the neural network through chemical intuition. We test CoeffNet on a dataset of SN2 reactions as a proof-of-concept and show that the activation barriers are predicted with a mean absolute error of less than 0.025 eV. The highest occupied molecular orbital of the transition state is visualized and the distribution of the orbital densities of the transition states is described for a few prototype SN2 reactions.

Prehospital hemorrhage management in low- and middle-income countries: A scoping review.

INTRODUCTION: Low- and middle-income countries (LMICs) account for 90% of deaths due to injury, largely due to hemorrhage. The increased hemorrhage mortality burden in LMICs is exacerbated by absent or ineffective prehospital care. Hemorrhage management (HM) is an essential component of prehospital care in LMICs, yet current practices for prehospital HM and outcomes from first responder HM training have yet to be summarized. METHODS: This review describes the current literature on prehospital HM and the impact of first responder HM training in LMICs. Articles published between January 2000 and January 2023 were identified using PMC, MEDLINE, and Scopus databases following PRISMA-ScR guidelines. Inclusion criteria spanned first responder training programs delivering prehospital care for HM. Relevant articles were assessed for quality using the Newcastle-Ottawa scale. RESULTS: Of the initial 994 articles, 20 met inclusion criteria representing 16 countries. Studies included randomized control trials, cohort studies, case control studies, reviews, and epidemiological studies. Basic HM curricula were found in 15 studies and advanced HM curricula were found in six studies. Traumatic hemorrhage was indicated in 17 studies while obstetric hemorrhage was indicated in three studies. First responders indicated HM use in 55%-76% of encounters, the most frequent skill they reported using. Mean improvements in HM knowledge acquisition post-course ranged from 23 to 58 percentage points following training for pressure and elevation, gauze application, and tourniquet application. CONCLUSIONS: Our study summarizes the current literature on prehospital HM in LMICs pertaining to epidemiology, interventions, and outcomes. HM resources should be a priority for further development.

Evaluating a digital hybrid training-of-trainers (TOT) approach for lay first responder trauma education in urban Nigeria during the COVID-19 pandemic.

INTRODUCTION: Road traffic injuries (RTIs) are the largest contributor to the global burden of injury, and in 2016 were among the five leading causes of global disability-adjusted life years (DALYs). In regions with limited emergency medical services (EMS), training lay first responders (LFRs) has been shown to increase availability of prehospital care for RTIs, but sustainable mechanisms to scale these programs remain unstudied. METHODS: Using a training of trainers (TOT) model, a 5.5-h LFR training program was launched in Lagos, Nigeria. The course was taught in a hybrid fashion with primary didactics using videoconferencing software and practical breakout sessions in-person concurrently. Thirty TOTs proceeded to train 350 transportation providers as LFRs over one month. A 23-question, pre- and post-assessment was administered digitally to assess knowledge acquisition. Participants responded to a five-point Likert survey assessing instruction quality and post-course confidence. RESULTS: TOTs scored a median of 56.5 % (IQR:43.5 %,71.7 %) and 91.3 % (IQR:88.0 %,95.7 %) on the pre- and post-assessments, respectively, with bleeding control scores increasing most (+69.4 %). LFR course trainees scored a median of 34.8 % (IQR: 26.0 %, 43.5 %) and 73.9 % (IQR: 65.2 %, 82.6 %) on the pre- and post-assessments respectively, with airway and breathing increasing the most (+48.6 %). All score increases were statistically significant with p < 0.001. All 30 TOT trainers instructed at least one training session after their initial session. LFR participants' rated confidence in first aid skills went from 3/5 (IQR 3, 4) pre-course to 5/5 (IQR:5,5) post-course, and in emergency transportation it went from 4/5 (IQR:3, 4) to 5/5 (IQR:5, 5), (p < 0.001). LFR course participants rated the quality of education content and TOT instructors to be 5/5 (IQR:5,5). 144 responders provided emergency care in the six-months following training for a total of 351 interventions. Active responders provided a median of 2 (IQR:1,3) interventions. CONCLUSIONS: This is the first time that a digital hybrid instruction for first responder trainers in low- and middle-income countries has been investigated. Our findings demonstrate negligible attrition, high educational quality ratings, equally effective knowledge acquisition to that of prior in-person courses, and high post-training skill usage. Future work will examine the cost-effectiveness of the training of LFRs and the effect of LFRs on trauma outcomes.

Prodromes in demyelinating disorders, amyotrophic lateral sclerosis, Parkinson disease, and Alzheimer's dementia.

A prodrome is an early set of symptoms, which indicates the onset of a disease; these symptoms are often non-specific. Prodromal phases are now recognized in multiple central nervous system diseases. The depth of understanding of the prodromal phase varies across diseases, being more nascent for multiple sclerosis for example, than for Parkinson disease or Alzheimer's disease. Key challenges when identifying the prodromal phase of a disease include the lack of specificity of prodromal symptoms, and consequent need for accessible and informative biomarkers. Further, heterogeneity of the prodromal phase may be influenced by age, sex, genetics and other poorly understood factors. Nonetheless, recognition that an individual is in the prodromal phase of disease offers the opportunity for earlier diagnosis and with it the opportunity for earlier intervention.

Identifying Risk Factors for Osteonecrosis After Talar Fracture.

OBJECTIVE: To identify patient, injury, and treatment factors associated with the development of avascular necrosis (AVN) after talar fractures, with particular interest in modifiable factors. DESIGN: Retrospective chart review. SETTING: 21 US trauma centers and 1 UK trauma center. PATIENT SELECTION CRITERIA: Patients with talar neck and/or body fractures from 2008 through 2018 were retrospectively reviewed. Only patients who were at least 18 years of age with fractures of the talar neck or body and minimum 12 months follow-up or earlier diagnosis of AVN were included. Further exclusion criteria included non-operatively treated fractures, pathologic fractures, pantalar dislocations, and fractures treated with primary arthrodesis or primary amputation. OUTCOME MEASUREMENTS AND COMPARISONS: The primary outcome measure was development of AVN. Infection, nonunion, and arthritis were secondary outcomes. RESULTS: In total, 798 patients (409 men; 389 women; age 18-81 years, average 38.6 years) with 798 (532 right; 264 left) fractures were included and were classified as Hawkins I (51), IIA (71), IIB (113), III (158), IV (40), neck plus body (177), and body (188). In total, 336 of 798 developed AVN (42%), more commonly after any neck fracture (47.0%) versus isolated body fracture (26.1%, P < 0.001). More severe Hawkins classification, combined neck and body fractures, body mass index, tobacco smoking, right-sided fractures, open fracture, dual anteromedial and anterolateral surgical approaches, and associated medial malleolus fracture were associated with AVN ( P < 0.05). After multivariate regression, fracture type, tobacco smoking, open fractures, dual approaches, age, and body mass index remained significant ( P < 0.05). Excluding late cases (>7 days), time to joint reduction for Hawkins type IIB-IV neck injuries was no different for those who developed AVN or not. AVN rates for reduction of dislocations within 6 hours of injury versus >6 hours were 48.8% and 57.5%, respectively. Complications included 60 (7.5%) infections and 70 (8.8%) nonunions. CONCLUSIONS: Forty-two percent of all talar fracture patients developed AVN, with talar neck fractures, more displaced fractures, and open injuries having higher rates. Injury-related factors are most prognostic of AVN risk. Surgical technique to emphasize anatomic reduction, without iatrogenic damage to remaining blood supply appears to be prudent. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Fungal and mycotoxin contaminants in cannabis and hemp flowers: implications for consumer health and directions for further research.

Medicinal and recreational uses of Cannabis sativa, commonly known as cannabis or hemp, has increased following its legalization in certain regions of the world. Cannabis and hemp plants interact with a community of microbes (i.e., the phytobiome), which can influence various aspects of the host plant. The fungal composition of the C. sativa phytobiome (i.e., mycobiome) currently consists of over 100 species of fungi, which includes phytopathogens, epiphytes, and endophytes, This mycobiome has often been understudied in research aimed at evaluating the safety of cannabis products for humans. Medical research has historically focused instead on substance use and medicinal uses of the plant. Because several components of the mycobiome are reported to produce toxic secondary metabolites (i.e., mycotoxins) that can potentially affect the health of humans and animals and initiate opportunistic infections in immunocompromised patients, there is a need to determine the potential health risks that these contaminants could pose for consumers. This review discusses the mycobiome of cannabis and hemp flowers with a focus on plant-infecting and toxigenic fungi that are most commonly found and are of potential concern (e.g., Aspergillus, Penicillium, Fusarium, and Mucor spp.). We review current regulations for molds and mycotoxins worldwide and review assessment methods including culture-based assays, liquid chromatography, immuno-based technologies, and emerging technologies for these contaminants. We also discuss approaches to reduce fungal contaminants on cannabis and hemp and identify future research needs for contaminant detection, data dissemination, and management approaches. These approaches are designed to yield safer products for all consumers.

The effect of different implant programs on beef × dairy steer feedlot growth performance and carcass characteristics.

The objective of this study was to evaluate potency and timing of trenbolone acetate (TBA) administration on live performance and carcass characteristics of beef × dairy steers. A total of 6,895 beef × dairy steers [initial body weight (BW) = 157 ±â€…5.2 kg] were allotted into 30 pens, with pen as the experimental unit. Each pen was randomly assigned one of three implant treatments: 1) Revalor-IS (IS) at d 0, IS at d 80, and Revalor-XS (XS) at d 160 (IS/IS/XS); 2) Ralgro at d 0, IS at d 80, and XS at d 160 (Ral/IS/XS); or 3) Encore at d 0 and XS at d 160 (Enc/XS). Steers were blocked by arrival date, each pen was terminally sorted in three ways at 257 ±â€…22 days on feed and harvested at 329 ±â€…25 days on feed. For live and carcass outcomes, fixed effect of implant treatment and random effect of block was evaluated. Data are reported on a deads and removals out basis. Removals, morbidity, and mortality were similar (P ≥ 0.45). Steers administered TBA prior to d 160 were 5.8 kg heavier (P = 0.03) than Enc/XS steers at d 160. Final BW was not different (P = 0.78). Early administration of a TBA-containing implant resulted in an increased prevalence of bullers [2.40%, 5.18%, 6.86% (for Enc/XS, Ral/IS/XS, and IS/IS/XS) respectively; P < 0.01]. Dry matter intake (DMI) was 2.3% greater (P < 0.01) in steers administered Enc/XS compared to IS/IS/XS; however, DMI as a percentage of BW, average daily gain, and feed efficiency were not different (P ≥ 0.12). Dressing percentage, hot carcass weight, heavy carcass occurrence, Longissimus muscle area, and 12th rib fat thickness were similar among all steers (P ≥ 0.28). Marbling score tended to be greatest for Enc/XS and Ral/IS/XS (P = 0.09). Enc/XS graded a greater proportion of USDA Prime and fewer USDA Select carcasses than IS/IS/XS (P < 0.05). Enc/XS and Ral/IS/XS tended (P = 0.09) to have more USDA Yield Grade (YG) 1 carcasses. While delayed administration or decreased total potency of TBA-containing implants may decrease buller incidence and improve Quality Grade, few differences were observed in live or carcass outcomes.

Critical Contribution of Imbalanced Charge Loss to Performance Deterioration of Si-Based Lithium-Ion Cells during Calendar Aging.

Increasing the energy density of lithium-ion batteries, and thereby reducing costs, is a major target for industry and academic research. One of the best opportunities is to replace the traditional graphite anode with a high-capacity anode material, such as silicon. However, Si-based lithium-ion batteries have been widely reported to suffer from a limited calendar life for automobile applications. Heretofore, there lacks a fundamental understanding of calendar aging for rationally developing mitigation strategies. Both open-circuit voltage and voltage-hold aging protocols were utilized to characterize the aging behavior of Si-based cells. Particularly, a high-precision leakage current measurement was applied to quantitatively measure the rate of parasitic reactions at the electrode/electrolyte interface. The rate of parasitic reactions at the Si anode was found 5 times and 15 times faster than those of LiNi0.8Mn0.1Co0.1O2 and LiFePO4 cathodes, respectively. The imbalanced charge loss from parasitic reactions plays a critical role in exacerbating performance deterioration. In addition, a linear relationship between capacity loss and charge consumption from parasitic reactions provides fundamental support to assess calendar life through voltage-hold tests. These new findings imply that longer calendar life can be achieved by suppressing parasitic reactions at the Si anode to balance charge consumption during calendar aging.

ECM-Focused Proteomic Analysis of Ear Punch Regeneration in Acomys Cahirinus.

In mammals, significant injury is generally followed by the formation of a fibrotic scar which provides structural integrity but fails to functionally restore damaged tissue. Spiny mice of the genus Acomys represent the first example of full skin autotomy in mammals. Acomys cahirinus has evolved extremely weak skin as a strategy to avoid predation and is able to repeatedly regenerate healthy tissue without scar after severe skin injury or full-thickness ear punches. Extracellular matrix (ECM) composition is a critical regulator of wound repair and scar formation and previous studies have suggested that alterations in its expression may be responsible for the differences in regenerative capacity observed between Mus musculus and A. cahirinus , yet analysis of this critical tissue component has been limited in previous studies by its insolubility and resistance to extraction. Here, we utilize a 2-step ECM-optimized extraction to perform proteomic analysis of tissue composition during wound repair after full-thickness ear punches in A. cahirinus and M. musculus from weeks 1 to 4 post-injury. We observe changes in a wide range of ECM proteins which have been previously implicated in wound regeneration and scar formation, including collagens, coagulation and provisional matrix proteins, and matricryptic signaling peptides. We additionally report differences in crosslinking enzyme activity and ECM protein solubility between Mus and Acomys. Furthermore, we observed rapid and sustained increases in CD206, a marker of pro-regenerative M2 macrophages, in Acomys, whereas little or no increase in CD206 was detected in Mus. Together, these findings contribute to a comprehensive understanding of tissue cues which drive the regenerative capacity of Acomys and identify a number of potential targets for future pro-regenerative therapies.

Workman's compensation as exclusion criteria in rotator cuff repair literature - are we inadvertently excluding race?

OBJECTIVE: Despite an equal willingness to participate in clinical trials, there is evidence that several minority populations are systematically under-represented in studies. One potential cause and frequently used exclusionary criterion in orthopedic trials is patients with active workman's compensation (WC) insurance claims. The purpose of this study is to determine demographic differences in patients undergoing arthroscopic rotator cuff repair with commercial and government insurance vs workers compensation claims. METHODS: This was a retrospective review of patients who underwent primary arthroscopic rotator cuff repair at a single institution in the northeastern United States from 2018 to 2019. Patients undergoing revision cases were excluded. Chart review was used to extract demographic data such as age, gender, insurance, and reported race. RESULTS: A total of 4553 patient records were reviewed and included. There were 742 WC patients and 3811 non-WC patients. Two hundred and forty-four patients did not report their race. Overall, WC patients differed from non-WC with respect to race (P < 0.001). One hundred and eleven (15.0%) of WC and 293 (7.7%) non-WC patients reported being 'Black' or 'African American' (P = 0.002). This compares to 368 (49.6%) WC and 2788 (73.2%) non-WC patients who reported 'White' (P < 0.001). About 16.8% of WC patients were identified as 'Hispanic or Latino,' compared to 5.2% of non-WC (P < 0.001). CONCLUSION: African American and Hispanic/Latino patients are over-represented in workman's compensation patient populations relative to non-workman's compensation. Conversely, white patients are over-represented in non-WC patient populations, which serve as the basis for the majority of clinical study populations. Excluding workman's compensation patients from clinical trials may lead to an underrepresentation of African American and Hispanic/Latino patient populations in orthopedic clinical trials. In doing so, the generalizability of the results of rotator cuff repair clinical outcomes research to all races and ethnicities may be compromised.

From volcanoes to the bench: Advantages of novel hyperthermoacidic archaeal proteases for proteomics workflows.

Here we introduce hyperthermoacidic archaeal proteases (HTA-Proteases©) isolated from organisms that thrive in nearly boiling acidic volcanic springs and investigate their use for bottom-up proteomic experiments. We find that HTA-Proteases have novel cleavage specificities, show no autolysis, function in dilute formic acid, and store at ambient temperature for years. HTA-Proteases function optimally at 70-90 °C and pH of 2-4 with rapid digestion kinetics. The extreme HTA-Protease reaction conditions actively denature sample proteins, obviate the use of chaotropes, are largely independent of reduction and alkylation, and allow for a one-step/five-minute sample preparation protocol without sample manipulation, dilution, or additional cleanup. We find that brief one-step HTA-Protease protocols significantly increase proteome and protein sequence coverage with datasets orthogonal to trypsin. Importantly, HTA-Protease digests markedly increase coverage and identifications for ribonucleoproteins, histones, and mitochondrial membrane proteins as compared to tryptic digests alone. In addition to increased coverage in these classes, HTA-Proteases and simplified one-step protocols are expected to reduce technical variability and advance the fields of clinical and high-throughput proteomics. This work reveals significant utility of heretofore unavailable HTA-Proteases for proteomic workflows. We discuss some of the potential for these remarkable enzymes to empower new proteomics methods, approaches, and biological insights. SIGNIFICANCE: Here we introduce new capabilities for bottom-up proteomics applications with hyperthermoacidic archaeal proteases (HTA-Proteases©). HTA-Proteases have novel cleavage specificity, require no chaotropes, and allow simple one-step/five-minute sample preparations that promise to reduce variability between samples and laboratories. HTA-Proteases generate unique sets of observable peptides that are non-overlapping with tryptic peptides and significantly increase sequence coverage and available peptide targets relative to trypsin alone. HTA-Proteases show some bias for the detection and coverage of nucleic acid-binding proteins and membrane proteins relative to trypsin. These new ultra-stable enzymes function optimally in nearly boiling acidic conditions, show no autolysis, and do not require aliquoting as they are stable for years at ambient temperatures. Used independently or in conjunction with tryptic digests, HTA-Proteases offer increased proteome coverage, unique peptide targets, and brief one-step protocols amenable to automation, rapid turnaround, and high-throughput approaches.