United States

Introduction: Glenohumeral instability has been shown to be common in sporting activities, with the highest rates particularly within contact sports such as wrestling. While operative management of shoulder instability has been published in the literature, few studies highlight outcomes and return to wrestling (RTW) in this subset of athletes. As such, the purpose of this study was to systematically review the current literature to identify reports of wrestlers with glenohumeral shoulder instability injuries to better understand the current state of treatment, outcomes, and RTW rate. 

Methods: We performed a systematic review examining treatments and RTW rates in competitive wrestlers. Studies published in PubMed, EMBASE, and the Cochrane Library reporting on competitive wrestlers who experienced shoulder instability from inception to July 2024 were identified. Human subjects, articles published in English, and studies reporting treatment (operative versus nonoperative), outcomes, RTW rates, and any complications were included. 

Results: 8 studies, consisting of 134 wrestlers presenting with shoulder instability with a weighted mean follow-up of 58.3 months, were identified. Weighted mean patient age was 18.8 years (range, 17-22 years), with 99% of patients included in this study being male. The most frequently reported instability was anterior shoulder instability, with 73.9% (n = 99/134) of athletes experiencing this shoulder instability. Instability events were reported in 132 athletes, with first time instability events occurring in 50.7% (n = 68/134) of athletes. Anterior labral tears were the most reported pathologic finding on imaging (n = 69/373), with anteroinferior labral tears representing 89.9% (n = 62/69) of these tears. Operative management was performed in 96.3% (n = 129/134) of athletes, and arthroscopic Bankart procedures were the most frequent surgical procedure at 76% (n = 98/129). Complications following treatment were reported in 17.9% (n = 24/134) of patients, with recurrent instability comprising 87.5% (n = 21/24) of noted complications. Eligibility for RTW was reported in 65% (n = 87/134) of wrestlers, with 62% (n = 54/87) RTW, while 60% (n = 52/87) returned to their previous level of activity. 

Conclusion: In competitive wrestlers, anterior instability represents the most common direction of shoulder instability. Operative management was the most preferred treatment option, being reported in 96.3% of cases. Given the low RTW rate and relatively high rate of recurrent instability, alternative procedures such as laterjet or open bankart repair may serve as more beneficial treatments in shoulder instability. Future studies should build on the present literature for wrestlers, to include increased detail regarding reoperation rates and time to RTW for various surgical revision procedures, as well as identifying when to perform adjunct procedures when treating these competitive athletes to gauge optimal management strategies. 


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Shoulder Instability Treatment and Outcomes in Competitive Wrestlers: A Systematic Review​

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Objective: The purpose of this study is to investigate the connection between the prevalence of metabolic syndrome and circadian misalignment in night shift workers. Understanding the impact of circadian rhythm disturbance on metabolic health is essential, especially in light of the growing incidence of night shift employment and its possible health consequences.
Methods: We searched Pubmed, Google Scholar, Cochrane Library and PLOS Medicine using relevant keywords such as “circadian misalignment, circadian rhythm disorders, circadian rhythm, metabolic syndrome, night-shift workers, insulin resistance”. We used “AND” and “OR” boolean operators for these keywords. We included peer-reviewed studies in humans that were published in the last 10 years (i.e., 2014–2024). The reference list of selected articles was also screened for relevant studies. Outcomes of interest were cardiometabolic outcomes, including obesity/body mass index (BMI), cardiovascular disease, diabetes, high blood pressure, fatty liver disease, and insulin resistance. This review focused on clinical trials, randomized clinical trials and meta-analysis. However, relevant observational studies were also included. There were no limitations on sample size or study location; however, only studies published in English and with adult participants over the age of 19 were considered in this review.
Results: A total of 37 articles met inclusion criteria and were added to the review. The key findings from these results show that compared to day workers, night shift workers have a higher chance of acquiring metabolic syndrome. Among night shift workers who experienced circadian misalignment, key metabolic syndrome components such as obesity, insulin resistance, dyslipidemia, and hypertension were common. The suggested pathophysiological processes include interrupted sleep patterns, modified eating behaviors, hormone abnormalities, and impaired glucose metabolism.
Conclusion: This review provides significant evidence that circadian misalignment in night shift workers contributes to the development of metabolic syndrome. The disruption of natural sleep-wake cycles contributes to metabolic syndrome, emphasizing the importance of tailored therapies to reduce its effects. Interventions targeting the reduction of circadian disturbance, such as the implementation of regulated lighting conditions, optimizing work schedules, and lifestyle adjustments, are crucial for minimizing the metabolic health hazards linked to night shift work. Additionally, implementing interventions that promote circadian alignment, such as improving sleep hygiene, and educating people about the benefits of regular sleep patterns, may help minimize the incidence of metabolic syndrome in this sensitive population. Future research should prioritize conducting longitudinal studies and intervention trials in order to demonstrate a causal relationship and develop efficacious preventive interventions.
Keywords: circadian misalignment, circadian rhythm disorders, circadian rhythm, night shift workers, insulin resistance, cardiovascular diseases, metabolic syndrome.


Relationship between Circadian Misalignment in Nightshift Workers and Metabolic Syndrome

Although the clinical results of infection with infectious prion proteins (PrPSc) have been well-studied, the physiological function of the cellular conformation (PrPc) has not been identified. One of the most common hypotheses is based around the assumption that the function of PrPc is one of protection primarily through anti-apoptosis. Using structural biology techniques to analyze sequence and structure, we compared the cellular prion protein to other known anti-apoptotic proteins in order to narrow down their true function. Our results showed that there was no significant similarity between the anti-apoptotic proteins and PrPc at either the active site or the N-terminus. These results emphasized that further research should be done to elucidate the physiological function of prion proteins in order to hopefully discover more effective treatments for prion diseases.

Narrowing Down the Physiologcal Function of the Cellular Prion Protein

Background: Type 1 Diabetes affects over 2.1 million patients in the United States and cost the healthcare system $14.4B in 2016. The current clinical standard for Type 1 Diabetes is daily glucose monitoring and exogenous insulin administration, which is medically and financially intensive. Islet cell transplantation could provide a curative solution but requires intense immunosuppression to avoid graft rejection.
Rapamycin, one part of this immunosuppressive protocol, delivered directly to antigen-presenting cells (APCs) maintains them in an immature state that leads to “co-stimulation blockade”, leading to anergy of T-cells. Polyethylene glycol- b-polypropylene sulfide polymers self-assemble into nanovesicles (PS) that can be loaded with hydrophobic drugs such as rapamycin (rPS). When injected subcutaneously, rPS is preferentially uptaken by macrophages, leading to targeted costimulation blockade4.
Burke et al. (2022) demonstrate that rPS induces extended survival of MHC- mismatched islet allografts and normoglycemia in a drug-induced diabetic mouse model4. We seek to validate these results in a non-obese diabetic (NOD) mouse model that replicates the inflammatory and autoimmune environment of Type 1 Diabetes pathology. Studies (Table 1) show that certain gut microbiome bacteria have increased populations in the states of immune tolerance.

Methods: NOD mice (age = 12 weeks) were injected with varying concentrations of rPS (0 mg/kg [PBS], 0.5 mg/kg, 1 mg/kg, 2 mg/kg, n =5 for each group) every 3 days for 18 days (total 6 doses). After the final dosing, mice were euthanized and their brachial/pancreatic lymph nodes, spleen, and cecal content were harvested. Cecal content was sent to Zymo Research for microbiological sequencing while lymph node and spleen samples were processed for flow cytometry.

Results: rPS exhibits a significant and positive dose dependent effect on the prevalence of the Blautia genus associated with induction of regulatory T cells and allograft survival. In the Lactobacillus genus, a statistically non-significant increase in prevalence is seen in the rPS 2 mg/kg group. Genus Alistipes was significantly decreased in prevalence in the 0.5 mg/kg rPS group.
Many rejection associated bacteria were not prevalent at all in the microbiota of both the controls and treatments.

Conclusions: The significant and dose associated effect of rPS on the Blautia genus shows that one mechanism of rPS’s tolerogenic effects may be through change of the gut microbiome. These results agree with previous pharmacologic characterization of rPS in significantly changing the immune population of CD80/86+ APCs and regulatory T cells.
The mechanism by which rPS affects the gut microbiome still needs to be elucidated. It is unclear whether rPS modulates the microbiome directly or if rPS’s previously established effects on the immune system allow for bacterial species associated with tolerance to flourish. In addition, each experimental group was not adequately powered to find significant associations in species outside of the Blautia genus. A larger study is required to confirm these results and establish the mechanism of causality.

Novel nanomedicine increases tolerance-associated species in the gut microbiota of non-obese diabetic mice

Biosafety of Intramuscular Autoinjection of Sulfanegen, a New Cyanide Antidote, in a Porcine Model
Deepali Shrivastava, Arreh Jain, Steven E. Patterson, Walt Tollison, John Carney, David Beebe, Kumar G. Belani
Background: Sulfanegen is a potent antidote to severe cyanide toxicity and can be administered intramuscularly. A proprietary intramuscular autoinjector has been developed for rapid administration during emergencies. This study investigated the safety of sulfanegen administered via the autoinjector in a porcine model, focusing on its systemic biochemical and metabolic toxicity and local tissue reaction.
Methods: After IACUC approval, eight healthy juvenile Yorkshire pigs (16-20 kg) were sedated with Tiletemine/Zolazepam (2-7 mg/kg) and Xylazine (0.2-1 mg/kg). Monitoring in these spontaneously breathing pigs included continuous EKG, pulse oximetry, respiratory rate, blood pressure, and temperature. Surface warming ensured normothermia. Blood samples were collected via peripheral venous blood before sulfanegen injection with a novel automatic injection system. The calculated body weight dose of Sulfanegen (75 mg/kg) was divided between two injectors and injected simultaneously into each of the hind thigh muscles. Hemodynamic parameters such as heart rate, respiratory rate, oxygen saturation, and core temperature were monitored throughout the procedure. Pre- and post-injection blood samples were collected for biochemical evaluation. After the Sulfanegen injection, the pigs recovered and observed for 7 days. They were then sedated again with the tiletamine/zolazepam and Xylazine mixture to collect metabolic blood samples and humanely euthanized for a necropsy. The muscle injection sites were grossly examined. Hemodynamic and biochemical data were analyzed using SPSS v27.
Results: All the pigs survived the Sulfanegen injection. Hemodynamics and biochemical parameters remained stable during and immediately following the injection without significant changes. Following emergence from anesthesia, all pigs were active and feeding appropriately. At necropsy, the local muscle tissue at the injection sites showed only minimal inflammation and no necrosis. Liver function, hematological, and metabolic tests at necropsy were within normal range.
Conclusion: In this porcine model, the intramuscular injection of Sulfanegen using the proprietary autoinjector device did not exert any adverse biochemical, hematological, or hemodynamic effects. There was only minimal local irritation at the injection sites. The next steps would be to examine the effects of increased doses of sulfanegen on muscle tissue in this model.


Biosafety of Intramuscular Autoinjection of Sulfanegen, a New Cyanide Antidote, in a Porcine Model

Background
Electroconvulsive therapy (ECT) is a procedure involving controlled seizures induced by electrical currents through the brain, all while a patient is under anesthesia and muscle paralysis. It is used to treat mental health conditions, including major depressive disorder, bipolar disorder, schizophrenia, and catatonia. Despite its effectiveness, ECT is underutilized, with only about 0.25% of mood disorder patients receiving it due to cost and stigma. Common anesthetics for ECT include etomidate and propofol. This research aims to further compare etomidate and propofol, and to find adequate evidence to support that etomidate is the better choice.

Methods
The narrative review employed a systematic search strategy to identify relevant studies on the use of Etomidate and Propofol as anesthetic agents in ECT. The search, conducted on January 21, 2024, utilized PubMed and Web of Science databases with key terms derived from MeSH and combined using Boolean operators. Inclusion criteria encompassed studies published until January 2024, accessed through PubMed, Scopus, and Web of Science, with reference lists of selected studies reviewed for additional relevant articles. Inclusion and exclusion criteria are outlined in this section. The review adheres to reporting standards outlined in the Scale for the Assessment of Narrative Review Articles.

Results
The tables present various study characteristics and results related to the use of different anesthetic agents in ECT. Table 1 outlines study details such as including medication dosages, exclusions, and patient populations across different countries and years. Table 2 provides population characteristics, including sample sizes and age ranges, mean ages, and gender distributions. Table 3 summarizes the results and conclusions of each study, highlighting findings such as induction times, seizure durations, hemodynamic stability, and incidence of myoclonus with different anesthetic agents. These tables collectively demonstrate the comparative effectiveness and safety profiles of Propofol, Etomidate, Thiopentone, and other anesthetic agents in ECT induction.

Conclusion
The narrative review examined the effects of Propofol and Etomidate on ECT. Propofol showed superiority over Etomidate in terms of shorter induction time, decreased seizure duration, and improved recovery times. Additionally, Propofol was associated with stable hemodynamics, shorter induction times, decreased seizure durations, and improved recovery times, along with stable hemodynamics. However, Etomidate was found to be more suitable for elderly patients due to quicker cognitive function recovery. Despite these findings’ differences, both drugs showed similar overall efficacy, indicating a need for further research, particularly exploring combined drug approaches for optimized treatment outcomes in ECT.


Comparison of Propofol or Etomidate in Electroconvulsive Therapy: A Narrative of Randomized Control Trials

Propofol in a Cardiac Setting: Recent Findings in Clinical Applicability and Protective Mechanisms

Researchers: Nizam Ali Karim B.S. Justin Viet Quang Le B.S.A. Zahir Malik Amin B.S. Harmandeep Singh B.S. Winston Tawiah B.S.
The University of Texas Medical Branch (UTMB) John Sealy School of Medicine, Galveston, TX

Background: Propofol is a widely used intravenous anesthetic agent known for its rapid onset and short duration of action. Beyond its primary anesthetic role, propofol has been found to possess cardioprotective properties. This study aims to investigate the mechanisms underlying these cardioprotective effects and evaluate their clinical applicability in cardiac medicine.

Methods: A systematic review was conducted using PubMed to ascertain published studies in the English language over the period of 2021-2024 using the appropriate search terms. The primary papers of interest were those that examined the cardioprotective effect of the intravenous anesthetic propofol. The search criteria yielded a total of 26 articles, which were then examined by three researchers for inclusion in the study. A total of 15 articles met the inclusion criteria and were included.

Results: The systematic review evaluated the cardioprotective effects of propofol in various preclinical and clinical settings. The studies reviewed included experiments on H9c2 rat-derived cardiac cells subjected to hypoxia/reoxygenation conditions, animal models of myocardial ischemia/reperfusion (I/R) injury, and clinical trials involving cardiac surgery patients. Propofol postconditioning (P-PostC) significantly reduced hypoxia/reoxygenation-induced apoptosis and autophagy in H9c2 cells. This effect was mediated by the upregulation of forkhead transcription factors FoxO1 and FoxO3a. Silencing these transcription factors reversed the cardioprotective effects, indicating their critical role in propofol's mechanism. Additionally, propofol alleviated oxidative stress, as evidenced by decreased reactive oxygen species (ROS) levels. In rat models, propofol pretreatment reduced myocardial infarct size, improved cardiac function, and decreased markers of myocardial injury such as lactate dehydrogenase (LDH) and creatine kinase (CK). Propofol also inhibited mast cell degranulation by reducing calcium influx through store-operated Ca2+ channels (SOCs) and activated the PI3K/AKT/Bcl-2 pathway, enhancing cell survival. Furthermore, in patients undergoing off-pump coronary artery bypass grafting (OPCABG), both volatile anesthetics and propofol demonstrated cardioprotective effects. However, volatile anesthetics slightly outperformed propofol in reducing myocardial injury markers such as troponin. Despite this, no significant difference in overall mortality or major morbidity was observed between these anesthetics.

Conclusion: Propofol exhibits significant cardioprotective effects through multiple mechanisms, including modulation of molecular pathways, inhibition of mast cell degranulation, activation of survival pathways, antioxidant activity, modulation of calcium homeostasis, and reduction of ischemia-reperfusion injury. Utilizing these effects, propofol can improve the quality of care in patients with cardiovascular conditions. Although its benefits in cardiac surgery are well-documented, further clinical research is warranted to optimize its use in non-surgical cardiac interventions.

Propofol in a Cardiac Setting: Recent Findings in Clinical Applicability and Protective
Mechanisms

Title: A Tale of Two Sexes: Exploring Differences in Right-Sided Heart Failure in a Porcine Model

Introduction: Right-sided heart failure (RHF) exhibits notable sex-based differences, with females generally demonstrating better right ventricular (RV) function compared to males. These disparities have significant prognostic implications, especially in RV-centric diseases like
pulmonary hypertension (PH), where RV dysfunction is linked to poor patient outcomes. Despite these observations, there are no therapies that specifically target the failing RV, and potential sex-based differences are understudied. Therefore, we evaluated the cellular and molecular responses to RHF in male and female pigs to identify potential sex-based differences.

Methods: 4-week-old male and female piglets underwent pulmonary artery banding (PAB) for six weeks to induce right ventricular dysfunction. Cardiac MRI changes in RV structure, function, volume, and mass. Wheat Germ Agglutinin evaluated cardiomyocyte hypertrophy. Super resolution confocal micrographs were analyzed using FIJI. Proteomics and metabolomics quantified RV metabolites and proteins.
Results: Despite having the same right ventricular ejection fraction, PAB-females had greater relative RV hypertrophy and dilation as assessed by cardiac MRI. Histologically, PAB-females had a nearly two-fold increase in RV cardiomyocyte cross sectional area compared to PAB-males. All four experimental groups clustered separately on hierarchical cluster analysis, suggesting significant groupwise differences in metabolomic profiles. Levels of triacylglycerols
and diacylglycerols were reduced in PAB-males and PAB-females compared to their controls. However, PAB-males had increased abundances of acylcarnitines, the mitochondrial form of fatty acids, compared to their controls, suggesting reduced fatty acid metabolism in PAB-males. Proteomics revealed reduced protein abundances in metabolic pathways in PAB-males, but not PAB-females. In addition, proteomics identified proteins in the cardiac muscle contraction
pathway are upregulated in PAB-males, compared to control males, but these proteins are mostly unchanged in PAB-females compared to control females.

Conclusion: Male and female piglets exhibit different cellular and molecular responses to PAB, despite similar levels of RV dysfunction. Females have a greater hypertrophic response, less metabolic/energetic derangements, and less relative sarcomeric protein upregulation compared to male pigs.

A Tale of Two Sexes: Exploring Right Sided Heart Failure in a Porcine Model

Air Pollution Induces Atrial Fibrosis via CARD9-Mediated Immune Response

Background
Exposure to ambient fine particulate matter (PM) triggers systemic inflammation and is associated with atrial fibrosis (AF) and cardiac arrhythmia. The cytosolic adaptor caspase recruitment domain 9 (CARD9) is crucial for macrophage function and innate immune response. This study aimed to investigate the role of CARD9-dependent immune response in PM-induced macrophage-mediated inflammation and the detrimental effects of PM on the heart atrium, exploring the underlying mechanisms.

Methods
Male C57BL/6 wild type (WT) mice (4-6 months old, n=8-12) and age- and sex-matched CARD9 knockout (CARD9-/-) mice (n=8-12) were intranasally exposed to PM for 1, 2, 7, 14, and 28 days. Serum levels of TNF-α, IL-1β, IL-6, and IL-10 were measured using ELISA. Total macrophage populations and M1/M2 subpopulations in bone marrow (BM) and blood were analyzed in mice with and without PM exposure. BM macrophages were cultured for 48 hours in M0, M1, or M2 medium to analyze their populations and cytokine production with or without PM exposure. Phosphorylated Akt (p-Akt), p-Erk, and Ankyrin-B levels were determined in atrial cardiomyocytes using immunoblotting. AF area was measured with Masson’s trichrome staining.

Results
PM exposure significantly elevated serum levels of TNF-α, IL-1β, and IL-6 in WT mice within 24 hours, but not in CARD9-/- mice. In CARD9-/- mice, PM exposure increased the M2 macrophage population and IL-10 levels compared to WT mice, with similar findings observed in vitro using BM cells cultured in M0, M1, and M2 media. PM-induced AF was linked to reduced atrial p-Akt and Ankyrin-B levels, effects that were mitigated in CARD9-/- mice compared to WT mice.

Conclusion
PM exposure-induced AF may be linked to an enhanced macrophage inflammatory response through CARD9-mediated reduction in IL-10 secretion, resulting in a decreased M2 macrophage polarization from M0 macrophage.

Air Pollution Induces Atrial Fibrosis via CARD9-Mediated Immune Response

Background: Excessive fibrosis can alter the electrical conduction in the atrial tissue leading to atrial fibrillation (AFib). However, the underlying mechanisms driving atrial fibrosis and the development of AFib remain incompletely understood. We hypothesized that atrial fibrosis could result due to coronary microvascular vasodilator dysfunction. 

Methods: Right human atrial appendages were collected during cardiac surgeries. Coronary arterioles (~100 µm) were dissected, cannulated, and pressurized (80 mmHg). Using video-microscopy, endothelium-dependent vasodilation was assessed by bradykinin (BK) and smooth muscle-dependent vasodilation was measured using sodium nitroprusside (SNP). Atrial tissue was then paraffin embedded and, via Masson’s Trichrome staining, the collagen content was quantified by ImageJ.

Results: When submitted to cumulative increases of bradykinin, AFib patients showed a significant reduced maximum vasodilation compared to the control patient with sinus rhythm (p=0.021), whereas no significant changes were recorded in SNP-induced vasodilator response. This decrease in BK-induced vasodilatory response was accompanied by a trend in increasing collagen content in the AFib patients, when compared to the control group (p=0.133). 

Conclusion: The collected data shows that patients with AFib have an increased collagen content in association with impaired endothelium-dependent vasodilatory response. Together, these data show that coronary microvascular dysfunction is accompanied by increased fibrosis, which may lead to hypoxia and AFib. 

Relevance for Patient Care: These data show a possible link between coronary microvascular dysfunction and Afib, which allows us to better understand AFib. 

Strengths/limitations: Limitations of this study include small sample size (n=8). The strength of these data is that these are samples taken from patients. 

Ethical Permissions: Ethical Approval was obtained for biological sample use.

Coronary Microvascular Dysfunction is Associated with Atrial Fibrosis in Patients with Atrial Fibrillation

Background: Abdominal aortic aneurysm (AAA) is a potentially lethal vascular disease lacking non-surgical treatments. AAA is associated with decreased expression of estrogen receptor alpha (ERα) in the aorta. The significance of this finding and the mechanisms by which lack of ERα signaling contributes to AAA pathogenesis have not been examined. In this investigation, we test the hypothesis that ERα signaling protects against AAA by decreasing endothelin-1 (ET-1) production and regulating inflammation.

Methods: AAA was induced in endothelial cell-specific ERα knockout (eERαKO) male mice and their littermates (ERαFL2) (n=6-11) by administering β-Aminopropionitrile (BAPN) via drinking water (1 mg/ml, 0.15 g/kg/d) 3 days before angiotensin II (Ang II; 1 µg/kg/day) infusion for 2 weeks. Development of AAA was assessed by in vivo ultrasound measurement of aortic luminal dilation. Relevant molecular mechanisms were examined in abdominal aortic tissues, human aortic endothelial cells (HAECs) and mouse bone marrow-derived macrophages (BMDMs). 

Results: BAPN/Ang II increased abdominal aortic diameter in ERαFL2 and eERαKO mice compared to control. Lack of ERα further augmented the BAPN/Ang II-induced increase in aortic diameter and AAA incidence compared to ERαFL2 mice. Immunohistochemical staining revealed that BAPN/Ang II co-infusion significantly upregulates ET-1 expression and macrophage infiltration of the abdominal aorta in eERαKO mice compared to ERαFL2 mice. In vitro studies in HAECs demonstrated that treatment with ERα agonist, β-estradiol (100 nM, 24 h), decreases TNFα (15 ng/ml)-induced ET-1 production, while treatment with ERα-specific antagonist, methylpiperidinopyrazole (1 µM, 24 h), increases ET-1 production. Additionally, BMDMs obtained from the eERαKO mice exhibited increased production of the pro-inflammatory cytokine monocyte chemoattractant protein-1 compared to macrophages from ERαFL2 mice.

Conclusion: Our findings demonstrate a protective effect of endothelial ERα signaling against AAA in male mice likely through decreased ET-1 production and reduced pro-inflammatory macrophage activation of the aorta. Further studies are needed to delineate the crosstalk between endothelial ET-1 with macrophage phenotype and their impact in AAA pathogenesis.

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