Regenerative inflammation: When immune cells help to re-build tissues

Inflammation is an essential immune response critical for responding to infection, injury and maintenance of tissue homeostasis. Upon injury, regenerative inflammation promotes tissue repair by a timed and coordinated infiltration of diverse cell types and the secretion of growth factors, cytokines and lipids mediators. Remarkably, throughout evolution as well as mammalian development, this type of physiological inflammation is highly associated with immunosuppression. For instance, regenerative inflammation is the consequence of an in situ macrophage polarization resulting in a transition from pro-inflammatory to anti-inflammatory/pro-regenerative response. Immune cells are the first responders upon injury, infiltrating the damaged tissue and initiating a pro-inflammatory response depleting cell debris and necrotic cells. After phagocytosis, macrophages undergo multiple coordinated metabolic and transcriptional changes allowing the transition and dictating the initiation of the regenerative phase. Differences between a highly efficient, complete ad integrum tissue repair, such as, acute skeletal muscle injury, and insufficient regenerative inflammation, as the one developing in Duchenne Muscular Dystrophy (DMD), highlight the importance of a coordinated response orchestrated by immune cells. During regenerative inflammation, these cells interact with others and alter the niche, affecting the character of inflammation itself and, therefore, the progression of tissue repair. Comparing acute muscle injury and chronic inflammation in DMD, we review how the same cells and molecules in different numbers, concentration and timing contribute to very different outcomes. Thus, it is important to understand and identify the distinct functions and secreted molecules of macrophages, and potentially other immune cells, during tissue repair, and the contributors to the macrophage switch leveraging this knowledge in treating diseases.

Post Cholecystectomy Bile Duct Injury in an Acute Setting: Categorization, Triaging, and Management Algorithm

Background Postcholecystectomy bile duct injury (BDI) is a management challenge with significant morbidity, mortality, and effects on long-term quality of life. Early referral to a specialized hepatobiliary center and appropriate early management are crucial to improving outcomes and overall quality of life. In this retrospective analysis, we examined patients who were managed at our center over the past 10 years and proposed a triage and management algorithm for BDI in acute settings. Methods Patients referred to our center with BDI from January 2011 to December 2020 were reviewed retrospectively. The primary objective of initial management is to control sepsis and minimize BDI-related morbidity and mortality. All the patients were resuscitated with intravenous fluid, antibiotics (preferably culture-based), correction of electrolyte deficiencies, and organ support if required. A triage module and management algorithm were framed based on our experience. All the patients were triaged based on the presence or absence of bile leaks. Each group was further subdivided into red, yellow, and green zones (depending on the presence of sepsis, organ failure, and associated injuries), and the results were analyzed as per the proposed algorithm. Results One hundred twenty-eight patients with acute BDI were referred to us during the study period, and 116 patients had BDI with a bile leak and 12 patients were without a bile leak. Out of bile leak patients, 106 patients (91.38%) had sepsis with or without organ failure (red and yellow zone) and required invasive intervention in the form of PCD insertion (n=99, 85.34%) and/or laparotomy, lavage, and drainage (n=7, 6.03%). Another 10 patients (8.62%) had controlled external biliary fistula (green zone), of which four were managed with antibiotics, four underwent endoscopic retrograde cholangiopancreatography stenting, and only two (1.7%) patients could undergo Roux-en-Y hepaticojejunostomy upfront due to late referral. Among patients with BDI without bile leaks, nine (75%) had cholangitis (red and yellow zones). Out of these, five required PTBD along with antibiotics and four were managed with antibiotics alone. Only three (25%) patients in this group could undergo definitive repair without any restriction on the timing of referral and were sepsis-free at presentation (green zone). A total of nine patients had a vascular injury, and four of them required digital subtraction angiography and coil embolization. There were three (2.34%) mortalities; all were in the red zone of rest and had successful initial management. In total, five patients were managed with early repair in the acute setting, and the rest underwent definitive intervention at subsequent admissions after being converted to green zone patients with initial management. Conclusion The presented categorization, triaging, and management algorithm provides optimum insight to understand the severity, simplify these complex scenarios, expedite the decision-making process, and thus enhance patient outcomes in early acute settings following BDI.

Urinary biomarkers as indicators of acute kidney injury in critically ill children exposed to vancomycin

STUDY OBJECTIVE

The standard of care for detecting acute kidney injury (AKI) is change in serum creatinine (SCr) and urine output, which are limited. This study aimed to compare urinary biomarkers neutrophil gelatinase-associated lipocalin (uNGAL) with kidney injury molecule-1 (uKIM-1) in critically ill children exposed to vancomycin who did and did not develop AKI as defined by changes in SCr.

DESIGN

Single-center, prospective, clinical, observational cohort study.

SETTING

Tertiary care children's hospital in an urban setting.

PATIENTS

Children aged 0 (corrected gestational age 42 weeks) to 18 years admitted to the intensive care unit who received vancomycin were included.

INTERVENTION

None.

MEASUREMENTS

The primary outcome was mean change in uNGAL and uKIM-1 between AKI and no-AKI groups. AKI was defined as a minimum 50% increase in SCr from baseline over a 48 h period, within 7 days of first vancomycin exposure. Three urine samples were collected: baseline (between 0 and 6 h of first vancomycin dose), second (18-24 h after the "baseline"), and third (18-24 h after the second sample). Concentrations of uKIM-1 and uNGAL were measured in each sample.

MAIN RESULTS

Forty-eight children (52% male; median age 6 years) were included. Eight (16.7%) children developed AKI. Mean changes in uNGAL (713.196 ± 1,216,474 vs. 16.101 ± 37.812 pg/mL; p = 0.0004) and uKIM-1 (6060 ± 11.165 vs. 340 ± 542 pg/mL; p = 0.0015) were greater in children with AKI versus no-AKI, respectively.

CONCLUSIONS

uNGAL and uKIM-1 concentrations increased significantly more in critically ill children with AKI compared with those with no-AKI during the first 48-72 h of vancomycin exposure and may be useful as prospective biomarkers of AKI.

Tracing the evolving dynamics and research hotspots of microbiota and immune microenvironment from the past to the new era

Gut microbiota can regulate many physiological processes within gastrointestinal tract and other distal sites. Dysbiosis may not only influence chronic diseases like the inflammatory bowel disease (IBD), metabolic disease, tumor and its therapeutic efficacy, but also deteriorate acute injuries. This article aims to review the documents in this field and summarize the research hotspots as well as developing processes. Gut microbiota and immune microenvironment-related documents from 1976 to 2022 were obtained from the Web of Science Core Collection database. Bibliometrics was used to assess the core authors and journals, most contributive countries and affiliations together with hotspots in this field and keyword co-occurrence analysis. Data were visualized to help comprehension. Nine hundred and twelve documents about gut microbiota and immune microenvironment were retrieved, and the annual publications increased gradually. The most productive author, country, and affiliation were "Zitvogel L," USA and "UNIV TEXAS MD ANDERSON CANC CTR," respectively. FRONTIERS IN IMMUNOLOGY, CANCERS, and INTERNATIONAL JOURNAL OF MOLECULAR SCIENCE were the periodicals with most publications. Keyword co-occurrence analysis identified three clusters, including gut microbiota, inflammation, and IBD. Combined with the visualized analysis of documents and keyword co-occurrence as well as literature reading, we recognized three key topics of gut microbiota: cancer and therapy; immunity, inflammation and IBD; acute injuries and metabolic diseases. This article revealed researches on gut microbiota and immune microenvironment were growing. More attention should be given to the latest hotspots like gut microbiota, inflammation, IBD, cancer and immunotherapy, acute traumas, and metabolic diseases.IMPORTANCEGut microbiota can regulate many physiological processes within gastrointestinal tract and other distal sites. Dysbiosis may not only influence chronic diseases like inflammatory bowel disease (IBD), metabolic disease, tumor and its therapeutic efficacy, but also deteriorate acute injuries. While the application of bibliometrics in the field of gut microbiota and immune microenvironment still remains blank, which focused more on the regulation of the gut microbiota on the immune microenvironment of different kinds of diseases. Here, we intended to review and summarize the presented documents in gut microbiota and immune microenvironment field by bibliometrics. And we revealed researches on gut microbiota and immune microenvironment were growing. More attention should be given to the latest hotspots like gut microbiota, inflammation, IBD, cancer and immunotherapy, acute traumas, and metabolic diseases.

The multifaceted role of macrophages during acute liver injury

The liver is situated at the interface of the gut and circulation where it acts as a filter for blood-borne and gut-derived microbes and biological molecules, promoting tolerance of non-invasive antigens while driving immune responses against pathogenic ones. Liver resident immune cells such as Kupffer cells (KCs), a subset of macrophages, maintain homeostasis under physiological conditions. However, upon liver injury, these cells and others recruited from circulation participate in the response to injury and the repair of tissue damage. Such response is thus spatially and temporally regulated and implicates interconnected cells of immune and non-immune nature. This review will describe the hepatic immune environment during acute liver injury and the subsequent wound healing process. In its early stages, the wound healing immune response involves a necroinflammatory process characterized by partial depletion of resident KCs and lymphocytes and a significant infiltration of myeloid cells including monocyte-derived macrophages (MoMFs) complemented by a wave of pro-inflammatory mediators. The subsequent repair stage includes restoring KCs, initiating angiogenesis, renewing extracellular matrix and enhancing proliferation/activation of resident parenchymal and mesenchymal cells. This review will focus on the multifaceted role of hepatic macrophages, including KCs and MoMFs, and their spatial distribution and roles during acute liver injury.

Insights into the pharmacodynamics and pharmacokinetics of meldonium after exposure to acute high altitude

Objective: Meldonium, a well-known cardioprotective drug, has been reported to be protective against pulmonary injury at high altitudes; however, the pharmacodynamics of meldonium in other vital organs under acute high-altitude injury are less investigated and the related pharmacokinetics have not been fully elucidated. Methods and Results: The present study examined the basic pharmacodynamics and pharmacokinetics (PK) in rat exposure to acute high-altitude hypoxia after intragastrical and intravenous pre-administration of meldonium. The results indicate that meldonium can improve acute hypoxia-induced pathological damage in brain and lung tissues, and restore blood biochemistry and routine blood index of heart, liver and kidney tissues under a simulated acute high-altitude environment. Furthermore, compared to the normoxia group, rats exposed to simulated high-altitude hypoxia and premedicated with intragastrical meldonium showed linear kinetics in the dose range of 25-100 mg/kg, with a significantly increase in the area under curve (AUC) and reduced clearance rate. No significant differences in these meldonium of PK parameters were observed with intravenous administration. Additionally, meldonium was involved in the regulation of succinic acid and 3-hydroxypropionic acid. Conclusion: These results will contribute to our understanding of the preclinical PK properties of meldonium and its acute high-altitude protective effects.

The Effectiveness of Trunk and Balance Warm-up Exercises in Prevention, Severity, and Length of Limitation From Overuse and Acute Lower Limb Injuries in Male Volleyball Players

Background

Injuries in volleyball players are most common in the ankles and knees. Many volleyball players suffer from overuse injuries because of the strain placed on the lower extremities from repeated jumping. A characteristic of players who are most at risk for lower extremity injuries is the tendency to display trunk instability during landing, such as lateral flexion and rotation. Research has shown the effectiveness of exercise-based warm-up interventions for acute volleyball injuries. However, comprehensive analyses on the use of lower extremity, trunk, and balance programs to prevent overuse injuries are lacking.

Purpose

To examine the effects of trunk and balance warm-up exercises on the prevention, severity, and length of limitation of overuse and acute lower limb injuries in male volleyball players.

Study Design

Prospective, single-cohort study.

Methods

This study involved the 2019 (control group) and 2021 (intervention group) male volleyball teams. The control and intervention groups were on the same team; however, seven players joined in 2021 through a sports referral program through which different players are recruited. Measurements included injury incidence rate, injury severity, and injury burden. The intervention involved the addition of trunk and balance exercises during the 2021 season.

Results

There was no significant difference in injury incidence rates between groups. Injury severity decreased by 3.7 days for overuse injuries (p=0.04). Injury burden decreased by 11.8 (days/1000 player hours) overall and by 7.1 (days/1000 player hours) for overuse injuries.

Conclusion

The results show that an exercise-based warm-up aimed at improving trunk posture during landing did not reduce the incidence rate of injury in men's volleyball. However, the addition of this warm-up did significantly reduce the severity of overuse injury.

Level of Evidence

Level 3B.

The role of interleukin-33 in organ fibrosis

Interleukin (IL)-33 is highly expressed in the nucleus of cells present at barrier sites and signals via the ST2 receptor. IL-33 signalling via ST2 is essential for return to tissue homeostasis after acute inflammation, promoting fibrinogenesis and wound healing at injury sites. However, this wound-healing response becomes aberrant during chronic or sustained inflammation, leading to transforming growth factor beta (TGF-β) release, excessive extracellular matrix deposition, and fibrosis. This review addresses the role of the IL-33 pathway in fibrotic diseases of the lung, liver, gastrointestinal tract, skin, kidney and heart. In the lung and liver, IL-33 release leads to the activation of pro-fibrotic TGF-β, and in these sites, IL-33 has clear pro-fibrotic roles. In the gastrointestinal tract, skin, and kidney, the role of IL-33 is more complex, being both pro-fibrotic and tissue protective. Finally, in the heart, IL-33 serves cardioprotective functions by favouring tissue healing and preventing cardiomyocyte death. Altogether, this review indicates the presence of an unclear and delicate balance between resolving and pro-fibrotic capabilities of IL-33, which has a central role in the modulation of type 2 inflammation and fibrosis in response to tissue injury.

Therapeutic Potential of Mesenchymal Stromal Cell-Derived Extracellular Vesicles in the Prevention of Organ Injuries Induced by Traumatic Hemorrhagic Shock

Severe trauma is the principal cause of death among young people worldwide. Hemorrhagic shock is the leading cause of death after severe trauma. Traumatic hemorrhagic shock (THS) is a complex phenomenon associating an absolute hypovolemia secondary to a sudden and significant extravascular blood loss, tissue injury, and, eventually, hypoxemia. These phenomena are responsible of secondary injuries such as coagulopathy, endotheliopathy, microcirculation failure, inflammation, and immune activation. Collectively, these dysfunctions lead to secondary organ failures and multi-organ failure (MOF). The development of MOF after severe trauma is one of the leading causes of morbidity and mortality, where immunological dysfunction plays a central role. Damage-associated molecular patterns induce an early and exaggerated activation of innate immunity and a suppression of adaptive immunity. Severe complications are associated with a prolonged and dysregulated immune–inflammatory state. The current challenge in the management of THS patients is preventing organ injury, which currently has no etiological treatment available. Modulating the immune response is a potential therapeutic strategy for preventing the complications of THS. Mesenchymal stromal cells (MSCs) are multipotent cells found in a large number of adult tissues and used in clinical practice as therapeutic agents for immunomodulation and tissue repair. There is growing evidence that their efficiency is mainly attributed to the secretion of a wide range of bioactive molecules and extracellular vesicles (EVs). Indeed, different experimental studies revealed that MSC-derived EVs (MSC-EVs) could modulate local and systemic deleterious immune response. Therefore, these new cell-free therapeutic products, easily stored and available immediately, represent a tremendous opportunity in the emergency context of shock. In this review, the pathophysiological environment of THS and, in particular, the crosstalk between the immune system and organ function are described. The potential therapeutic benefits of MSCs or their EVs in treating THS are discussed based on the current knowledge. Understanding the key mechanisms of immune deregulation leading to organ damage is a crucial element in order to optimize the preparation of EVs and potentiate their therapeutic effect.

Age Is More Predictive of Safe Movement Patterns Than Are Physical Activity or Sports Specialization: A Prospective Motion Analysis Study of Young Athletes

BACKGROUND

Movement quality and neuromuscular balance are noted predictors of acute injury. Early sports specialization and extremely high activity levels have been linked to elevated risk of injury.

PURPOSE

To investigate for any relationships among quality of physical movement, quantity of physical activity, and degree of sports specialization in a healthy cohort of active children and adolescents.

STUDY DESIGN

Cross-sectional study with prospectively collected data.

METHODS

Healthy children between the ages of 10 and 18 years were recruited and completed the Hospital for Special Surgery Pediatric Functional Activity Brief Scale to assess quantity of physical activity and the Jayanthi scale to assess degree of sports specialization (high, score of 2 or 3; low, score of 0 or 1). Movement quality was assessed using motion analysis sensors during 5 repetitions of 4 different jumping and squatting motions, with a maximum score of 100 per participant. Independent-samples t tests were used to compare participants with high versus low specialization on physical activity and movement quality. A Spearman correlation was used to determine the relationship between quantity of physical activity and movement quality, and linear regression was used to assess for the effect of participant age on relevant covariables.

RESULTS

Final analyses included 147 participants (72% male) with a mean ± SD age of 13.4 ± 2.2 years. Participants who were highly specialized displayed better movement quality than did participants with low sports specialization (27.6 ± 14.0 vs 19.8 ± 10.1; P < .01). Participants who were highly specialized had significantly higher activity levels (24.6 ± 5.9 vs 18.1 ± 6.9; P < .001). Movement quality was moderately correlated with physical activity level (r = 0.335; P < .001). Physical activity; hours of organized sports activity; hours of free, unorganized physical activity; and specialization level were not significant predictors of movement quality when controlling for age. Age alone predicted 24.2% of the variance in the overall movement quality score (R² = 0.242; B = 3.0; P < .001).

CONCLUSION

This study found that sports specialization and physical activity levels were not associated with movement quality when controlling for age, which was the most important variable predicting athletic movement quality. Although all participants displayed movement patterns that were associated with high risk for injury, overall movement quality improved with advancing chronological age.

CLINICAL RELEVANCE

All young athletes should ensure that neuromuscular training accompanies sport-specific training to reduce risk of injury.

Epigallocatechin Gallate Can Protect Mice From Acute Stress Induced by LPS While Stabilizing Gut Microbes and Serum Metabolites Levels

Epigallocatechin gallate (EGCG) has potent biological activity as well as strong antioxidant and anti-inflammatory effects. This study aims to explore the protective effect of EGCG on LPS-induced acute injury. We randomly divided 18 mice into three groups: CON, LPS, and EGCG-LPS. We gave the EGCG-LPS group gavage treatment with EGCG on day 8–15 and an intraperitoneal injection of LPS on day 16 to induce acute injury. The results showed that, compared with the LPS group, the bodyweight of the mice in the EGCG-LPS group increased significantly and effectively inhibited the morphological damage of the jejunum and liver. We measured liver tissue and found that the EGCG gavage treatment significantly inhibited the pro-inflammatory factors (TNF-α, IL-1β, IL-6, MCP-1, MIP-2, IFN-γ) and oxidation indicators (MPO, NO, ALT, and AST) levels increase. The microbiological results showed that the EGCG gavage treatment reshaped the disturbance done to the intestinal microbial community in the mice by LPS, reversed the changes in the abundance ratio of Firmicutes/Bacteroidetes, and significantly reduced the abundance of Enterobacteriales. Finally, the serum metabolomics results showed that, when compared with the LPS group, the gavage treatment of EGCG significantly increased the concentration of sphingomyelin (d17:1/17:0), sphingomyelin (d16:1/20:0), and significantly reduced the content of trans-Hexadec-2-enoyl carnitine, and so on. Therefore, we believe that EGCG can protect mice from acute stress induced by LPS while stabilizing gut microbes in general, improving the metabolism of sphingolipids, and inhibiting the content of harmful metabolites.

Prevalence and Site of Medial Patellofemoral Ligament Injuries in Patients With Acute Lateral Patellar Dislocations: A Systematic Review and Meta-analysis

Background

Medial patellofemoral ligament (MPFL) injuries are common in patients with acute lateral patellar dislocations, but the pattern of MPFL injuries is unclear, especially with respect to patient age.

Purpose

The primary aim was to determine the prevalence of MPFL injuries according to the site of injury in patients with acute lateral patellar dislocations. The secondary aim was to compare the site of MPFL injuries in patients aged ≤16 versus >16 years.

Study Design

Systematic review; Level of evidence, 4.

Methods

A systematic literature search was performed with PubMed, Embase, and CINAHL to identify articles published from January 1, 1999, to May 31, 2019, that examined the site of MPFL injuries in patients with acute patellar dislocations. The study design, sample size, age at injury, technique used for diagnosing MPFL injuries (magnetic resonance imaging, ultrasound, and/or surgery), and prevalence and site of MPFL injuries were extracted from each study. The pooled estimate of the proportion of MPFL injuries at each site was calculated (femur, patella, midsubstance, and combined sites of injury) as well as proportions stratified by age group (≤16 and >16 years).

Results

The literature search yielded 420 unique articles, of which 52 were screened for eligibility; of these, 17 were excluded. Thus, a total of 35 articles (2558 patients) were included in the final analysis. The overall prevalence of MPFL injuries was 94.7% (95% CI, 91.2%-96.8%). Most MPFL injuries occurred at the patella (37.1% [95% CI, 30.8%-43.9%]), followed by the femur (36.8% [95% CI, 31.0%-43.0%]), combined sites (25.1% [95% CI, 20.7%-30.1%]), and the midsubstance (15.6% [95% CI, 13.2%-18.4%]). In patients aged ≤16 years, most MPFL injuries occurred at the patella (39.3% [95% CI, 27.9%-51.9%]), and in patients aged >16 years, most MPFL injuries occurred at the femur (47.2% [95% CI, 40.6%-54.0%]).

Conclusion

The prevalence of MPFL injuries in patients with acute patellar dislocations varied by site of injury and by age. MPFL injuries at the patella were most prevalent overall and in children and adolescents, and MPFL injuries at the femur were more prevalent in adults.

Acromioclavicular Joint Injuries in Professional Ice Hockey Players: Epidemiologic and MRI Findings and Association With Return to Play

Background:

Acromioclavicular joint (ACJ) injuries are common in ice hockey players and are traditionally evaluated with conventional radiography, which has recognized limitations in the accurate characterization of the spectrum of soft tissue injuries and severity/grade of injury sustained.

Purpose:

To evaluate the epidemiologic, clinical, and magnetic resonance imaging (MRI) findings in professional ice hockey players who have sustained acute ACJ injuries.

Study Design:

Case series; Level of evidence, 4.

Methods:

A retrospective review was performed of professional National Hockey League (NHL) players referred for MRI evaluation of acute ACJ injuries. All MRI scans were assessed for status of the ACJ, ligamentous stabilizers, and surrounding musculature. MRI-based overall grade of ACJ injury (modified Rockwood grade 1-6) was assigned to each case. Data regarding mechanism of injury, player handedness, clinical features, and return to play were evaluated.

Results:

Overall, 24 MRI examinations of acute ACJ injuries (23 patients; mean age, 24 years) were reviewed. We found that 50% of injuries were sustained during the first period of play, and in 75% of cases, injuries involved the same side as player shooting handedness. Analysis of MRI scans revealed 29% (7/24) grade 1 ACJ injuries, 46% (11/24) grade 2 injuries, 21% (5/24) grade 3 injuries, and 4% (1/24) grade 5 injuries. Trapezius muscle strains were seen in 79% and deltoid muscle strain in 50% of cases. Nonoperative management was used for 23 injuries; 1 patient (grade 5 injury) underwent acute reconstructive surgery. All players successfully returned to professional NHL competition. Excluding cases with additional injuries or surgery (n = 3) or convalescence extending into the offseason (n = 3), we found that the mean return to play was 21.4 days (7.2 games missed). No statistically significant difference was observed in return to play between nonoperatively treated grade 3 injuries (mean, 28.3 days) and grade 1 or 2 injuries (mean, 20.1 days). However, grade 3 injuries were associated with a greater number of NHL scheduled games missed (mean, 12.7) compared with lower grade injuries (mean, 6.1) (P = .027).

Conclusion:

The spectrum of pathology and grading of acute ACJ injuries sustained in professional ice hockey can be accurately assessed with MRI; the majority of injuries observed in this study were low grade (grades 1 and 2). Although grade 3 injuries were associated with a greater number of games missed, similar return-to-play results were observed between nonoperatively treated grade 3 and grade 1 or 2 ACJ injuries.

The protective effect of decoction of Rehmanniae via PI3K/Akt/mTOR pathway in MPP+-induced Parkinson's disease model cells

This research aims to explore the function of DOR in 1-methyl-4-phenylpyridinium (MPP⁺)-induced Parkinson's disease model cell SH-SY5Y. SH-SY5Y cells were exposed with various doses of MPP + or DOR. Cell counting Kit-8 (CCK-8) assay and flow cytometry (FCM) were used to detect the cell viability, apoptosis and reactive oxygen species (ROS) levels in MPP⁺ Parkinson's disease model cells SH-SY5Y. The oxidative stress markers were measured by Enzyme-linked immunosorbent assay (ELISA), Western blot and quantitative real-time reverse transcription PCR (qRT-PCR) assays. To further determine the protective effect of DOR on acute injury via PI3K/Akt/mTOR pathway, cells were treated with LY294002 (LY), a PI3K/Akt/mTOR pathway inhibitor, with MMP + or DOR or not. MPP⁺ at various doses caused cell injury with decrease of viability, increase of apoptosis and ROS level, while DOR partly prevented the cell against injury induced by MPP⁺. Bax, Cyt-c and cleaved-Caspase-12, 9 and 3 were increased, and meanwhile Bcl-2 was decreased in MPP⁺ stimulated cells, while those changes could be partly inhibited by DOR incubation. Furthermore, the phosphorylation level of PI3K, AKT and mTOR was suppressed by MPP⁺, while DOR treatment could enhanced the level of phosphorylated-PI3K (p-PI3K), AKT (P-AKT) and mTOR. LY aggravated the injury of SH-SY5Y cells treated with MPP⁺, and DOR could partly alleviate those effects. DOR had a protective effect against MPP⁺ induced injury of Parkinson's disease model cell through activating the PI3K/Akt/mTOR pathway. It suggests that DOR should be further explored in Parkinson's disease.

Dupuytren's Contracture: Incidence of Injury-Induced Cases and Specific Clinical Expression

Background and objectives: Dupuytren’s contracture is a chronic fibroproliferative hand disorder with a varying pattern of genetic predisposition across different regions and populations. Traumatic events have been found to have influence on the development of this illness and are likely to trigger different clinical forms of this disease. The aim of this study was to evaluate the phenomenon of development of Dupuytren’s contracture (DC) following an acute injury to the hand, and to observe the incidence and clinical diversity of such cases in daily clinical practice. Materials and Methods: We collected data of patients presenting with primary Dupuytren’s contracture in the Lithuanian population and evaluated the occurrence and clinical manifestation of this specific type of DC, arising following acute hand trauma. The diagnosis of DC was based on clinical signs and physical examination. Digit contractures were measured by goniometry, and the staging was done according to Tubiana classification. Injury-induced (injury-related) cases were identified using the “Criteria for recognition of Dupuytren’s contracture after acute injury” (established by Elliot and Ragoowansi). Results: 29 (22%) of a total of 132 cases were injury-induced DCs. Twenty-six of 29 patients in this group presented with stage I–II contractures. Duration of symptoms was 6 (SD 2.2) and 3.8 (SD 2.2) years in the injury-related and injury-unrelated DC groups, respectively. Mean age on the onset of symptoms in the injury-induced and non-injury-induced groups was 52 (SD 10.7) and 56 (SD 10.9), respectively. Patients from both groups expressed strong predisposition towards development of DC. Conclusions: Around one-fifth of patients seeking treatment for primary Dupuytren’s contracture seemed to suffer from injury-induced Dupuytren’s contracture. We noted that injury to the wrist and hand seems to trigger the development of less progressive Dupuytren’s contracture in younger age. Prospective randomized studies are required to confirm our findings.

Relationship Between Spinal-Pelvic Sagittal Balance and Pelvic-Femoral Injuries in Professional Soccer Players

Background

Pelvic-femoral injuries are a common problem in football (soccer) players. However, the risk factors for these injuries are unclear. Our knowledge of spinal-pelvic sagittal balance has increased considerably over the past few years, notably as a result of new radiographic techniques such the EOS radiographic imaging system.

Purpose

To investigate the link between spinal-pelvic sagittal balance on EOS imaging and the incidence of pelvic-femoral injuries.

Study Design

Cohort study; Level of evidence, 2.

Methods

Players in a League 1 professional soccer team were observed for 5 consecutive seasons. All players included in the study underwent EOS radiographic imaging. All acute and microtraumatic injuries to the pelvic-femoral complex were recorded prospectively: hamstrings, psoas, quadriceps, adductors, obturators, and pubic symphysis. We analyzed the relationship between injury incidence and key radiographic parameters involved in pelvic balance.

Results

A total of 61 players were included (mean age, 24.5 years; n = 149 injuries; mean pelvic tilt, 9.08° ± 5.6°). A significant link was observed between the incidence of pelvic-femoral injuries and pelvic tilt (P = .02). A significant link was also observed between the incidence of acute pelvic-femoral injuries and pelvic tilt (P = .05). In both cases, a high pelvic tilt was associated with a low incidence of injuries.

Conclusion

In professional soccer players, a low pelvic tilt was associated with a high incidence of all pelvic-femoral injuries as well as acute pelvic-femoral injuries. These results could lead to new preventive methods for these musculotendinous injuries through physical therapy.

[Effectiveness of open reduction and internal fixation for acute and delayed occult Lisfranc injuries]

Objective

To evaluate the effectiveness of open reduction and internal fixation (ORIF) in treatment of acute and delayed occult Lisfranc injuries.

Methods

A retrospective review of 26 patients with occult Lisfranc injuries who were treated with ORIF between July 2010 and July 2015 was applied. Fourteen patients were treated within 6 weeks after injury (acute group) and 12 patients were treated after 6 weeks of injury (delayed group). There was no significant difference between the two groups in gender, age, affected sides, and preoperative visual analogue scale (VAS) score, American Orthopedic Foot and Ankle Society (AOFAS) score, and physical and mental scores of Study Short Form 12 Health Survey (SF-12) ( P<0.05). The joint reduction, internal fixator, and traumatic osteoarthritis were observed by X-ray films. The pain degree, midfoot function, and quality of life were evaluated with VAS score, AOFAS score, and physical and mental scores of SF-12.

Results

All incisions healed by first intention with no complications. All patients were followed up with the mean follow-up time of 15 months (range, 12-24 months) in acute group and 15 months (range, 12-23 months) in delayed group. At last follow-up, the VAS score, AOFAS score, and physical and mental scores of SF-12 were superior to those before operation in the two groups ( P<0.05). And there was no significant difference in all indicators between the two groups ( P>0.05). The satisfaction rates were 100% and 83.3% (10/12) in acute group and delayed group, respectively. The internal fixators were removed in 20 patients (11 cases in acute group and 9 cases in delayed group) at 9-24 months after operation (mean, 14.5 months). The results of X-ray films showed no traumatic osteoarthritis, midfoot collapse, internal fixation failure, or reduction loss during follow-up period.

Conclusion

ORIF is an ideal method for both acute and delayed occult Lisfranc injuries and can obtain the similar effectiveness.

Acute Injuries in Male Elite and Amateur Mountain Bikers: Results of a Survey

Together with the growing popularity of mountain biking, the number of riders at risk for an acute injury has increased. A cross-sectional observational study was performed to describe the prevalence of acute injuries among elite and amateur riders and to determine predictive factors leading to a severe injury. A retrospective questionnaire was created comprising questions aiming on demographics, training volume, injury events and wearing of protective gear items. The survey was conducted during the Swiss Epic Mountain Bike Event in 2017. Complete data sets of male mountain bikers were used to determine prevalence. To evaluate injury related factors, only data sets reporting one or more injuries were included in the final analysis. Ninety-nine questionnaires were included to calculate the injury prevalence of 74% for elites and 69% for amateurs (p = 0.607). For the analysis of injury related factors 56 questionnaires were processed. Elites were significantly younger (p = 0.004) and had a significantly higher exposure time per year as amateurs (p < 0.001). The groups did not differ in number of injuries (p = 0.437) and number of severe injuries (p = 0.225). No predictive factors for a severe injury event were found. Both groups wore an equal amount of protective gear items (p = 0.846). A significant medium, respectively small correlation was found in both groups for mean hours of training per week and number of races per year (elites: r = 0.597, p = 0.023; amateurs: r = 0.428, p = 0.005). An equal prevalence of acute injuries was found in elite and amateur mountain bikers. Elites are at higher risk for an injury event due to their exposure time but do not suffer more or more severe injuries than amateurs.

The Protective Effect of Magnesium Lithospermate B on Hepatic Ischemia/Reperfusion via Inhibiting the Jak2/Stat3 Signaling Pathway

Acute inflammation is an important component of the pathogenesis of hepatic ischemia/reperfusion injury (HIRI). Magnesium lithospermate B (MLB) has strong neuroprotective and cardioprotective effects. The purpose of this study was to determine whether MLB had underlying protective effects against hepatic I/R injury and to reveal the potential mechanisms related to the hepatoprotective effects. In this study, we first examined the protective effect of MLB on HIRI in mice that underwent 1 h ischemia followed by 6 h reperfusion. MLB pretreatment alleviated the abnormal liver function and hepatocyte damage induced by I/R injury. We found that serum inflammatory cytokines, including IL-6, IL-1β, and TNF-α, were significantly decreased by MLB during hepatic ischemia/reperfusion (I/R) injury, suggesting that MLB may alleviate hepatic I/R injury via inhibiting inflammatory signaling pathways. Second, we investigated the protein level of p-Jak2/Jak2 and p-Stat3/Stat3 using Western blotting and found that MLB could significantly inhibit the activation of the Jak2/Stat3 signaling pathway, which was further verified by AG490 in a mouse model. Finally, the effect of MLB on the Jak2/Stat3 pathway was further assessed in an in vitro model of RAW 264.7 cells; 1 µg/ml LPS induced the secretion of inflammatory mediators, including IL-6, TNF-α, and activation of the Jak2/Stat3 signaling pathway. MLB significantly inhibited the abnormal secretion of inflammatory factors and the activation of the Jak2/Stat3 signaling pathway in RAW264.7 cells. In conclusion, MLB was found for the first time to reduce inflammation induced by hepatic I/R via suppressing the Jak2/Stat3 pathway.

Surviving Acute Organ Failure: Cell Polyploidization and Progenitor Proliferation

In acute organ failure, rapid compensation of function loss assures survival. Dedifferentiation and/or proliferation of surviving parenchymal cells could imply a transient (and potentially fatal) impairment of residual functional performance. However, evolution has selected two flexible life-saving mechanisms acting synergistically on organ function recovery. Sustaining residual performance is possible when the remnant differentiated parenchymal cells avoid cell division, but increase function by undergoing hypertrophy via endoreplication, leading to polyploid cells. In addition, tissue progenitors, representing a subset of less-differentiated and/or self-renewing parenchymal cells completing cytokinesis, proliferate and differentiate to regenerate lost parenchymal cells. Here, we review the evolving evidence on polyploidization and progenitor-driven regeneration in acute liver, heart, and kidney failure with evolutionary advantages and trade-offs in organ repair.

Operative Management of Acute Triceps Tendon Ruptures: Review of 184 Cases

BACKGROUND

Distal triceps tendon ruptures are rare. The authors present a series of 184 surgically treated, acute, traumatic triceps tendon avulsions and compare the complications between those treated with anchors (A) versus transosseous (TO) suture repair.

HYPOTHESIS

No difference exists in the retear rate between TO and A repairs. Study Designed: Cohort study; Level of evidence, 3.

METHODS

All patients who underwent an open primary repair of a traumatic triceps tendon avulsion within 90 days of injury, between 2007 and 2015, were retrospectively reviewed. Surgeries were performed within a multisurgeon (75 surgeons), multicenter (14 centers), community-based integrated health care system. Patient demographic information, type of repair, complications, and time from surgery to release from medical care were recorded.

RESULTS

184 triceps tears in 181 patients met the inclusion criteria. The mean age was 49 years (range, 15-83 years). There were 169 males. The most common mechanisms of injury were fall (56.5%) and weight lifting (19%). Mean time from injury to surgery was 19 days (range, 1-90 days); in 74.5% of cases, surgery was performed in 3 weeks or less. There were 105 TO and 73 A repairs. No significant difference was found between the two groups in the mean age ( P = .18), sex ( P = .51), completeness of tears ( P = .74), tourniquet time ( P = .455), and prevalence of smokers ( P = .64). Significant differences were noted between TO and A repairs in terms of reruptures (6.7% vs 0%, respectively; P = .0244), overall reoperation rate (9.5% vs 1.4%; P = .026), and release from medical care (4.3 vs 3.4 months; P = .0014), but no difference was seen in infection rate (3.8% vs 0%; P = .092). No difference was noted in release from medical care in patients who underwent surgery 3 weeks or less after injury compared with those undergoing surgery more than 3 weeks after injury (3.90 vs 4.09 months, respectively; P = .911).

CONCLUSION

Primary repair of triceps ruptures with TO fixation has a significantly higher rerupture rate, higher reoperation rate, and longer release from medical care than does repair with A fixation. Implementation of suture anchors in triceps repairs offers a lower complication rate and earlier release from medical care.

Automated T2-mapping of the Menisci From Magnetic Resonance Images in Patients with Acute Knee Injury

RATIONALE AND OBJECTIVES

This study aimed to evaluate the accuracy of an automated method for segmentation and T2 mapping of the medial meniscus (MM) and lateral meniscus (LM) in clinical magnetic resonance images from patients with acute knee injury.

MATERIALS AND METHODS

Eighty patients scheduled for surgery of an anterior cruciate ligament or meniscal injury underwent magnetic resonance imaging of the knee (multiplanar two-dimensional [2D] turbo spin echo [TSE] or three-dimensional [3D]-TSE examinations, T2 mapping). Each meniscus was automatically segmented from the 2D-TSE (composite volume) or 3D-TSE images, auto-partitioned into anterior, mid, and posterior regions, and co-registered onto the T2 maps. The Dice similarity index (spatial overlap) was calculated between automated and manual segmentations of 2D-TSE (15 patients), 3D-TSE (16 patients), and corresponding T2 maps (31 patients). Pearson and intraclass correlation coefficients (ICC) were calculated between automated and manual T2 values. T2 values were compared (Wilcoxon rank sum tests) between torn and non-torn menisci for the subset of patients with both manual and automated segmentations to compare statistical outcomes of both methods.

RESULTS

The Dice similarity index values for the 2D-TSE, 3D-TSE, and T2 map volumes, respectively, were 76.4%, 84.3%, and 75.2% for the MM and 76.4%, 85.1%, and 76.1% for the LM. There were strong correlations between automated and manual T2 values (r_MM = 0.95, ICC_MM = 0.94; r_LM = 0.97, ICC_LM = 0.97). For both the manual and the automated methods, T2 values were significantly higher in torn than in non-torn MM for the full meniscus and its subregions (P < .05). Non-torn LM had higher T2 values than non-torn MM (P < .05).

CONCLUSIONS

The present automated method offers a promising alternative to manual T2 mapping analyses of the menisci and a considerable advance for integration into clinical workflows.

Global and Regional Brain Non-Gaussian Diffusion Changes in Newly Diagnosed Patients with Obstructive Sleep Apnea

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) patients show brain structural injury and functional deficits in autonomic, affective, and cognitive regulatory sites, as revealed by mean diffusivity (MD) and other imaging procedures. The time course and nature of gray and white matter injury can be revealed in more detail with mean kurtosis (MK) procedures, which can differentiate acute from chronic injury, and better show extent of damage over MD procedures. Our objective was to examine global and regional MK changes in newly diagnosed OSA, relative to control subjects.

METHODS

Two diffusion kurtosis image series were collected from 22 recently-diagnosed, treatment-naïve OSA and 26 control subjects using a 3.0-Tesla MRI scanner. MK maps were generated, normalized to a common space, smoothed, and compared voxel-by-voxel between groups using analysis of covariance (covariates; age, sex).

RESULTS

No age or sex differences appeared, but body mass index, sleep, neuropsychologic, and cognitive scores significantly differed between groups. MK values were significantly increased globally in OSA over controls, and in multiple localized sites, including the basal forebrain, extending to the hypothalamus, hippocampus, thalamus, insular cortices, basal ganglia, limbic regions, cerebellar areas, parietal cortices, ventral temporal lobe, ventrolateral medulla, and midline pons. Multiple sites, including the insular cortices, ventrolateral medulla, and midline pons showed more injury over previously identified damage with MD procedures, with damage often lateralized.

CONCLUSIONS

Global mean kurtosis values are significantly increased in obstructive sleep apnea (OSA), suggesting acute tissue injury, and these changes are principally localized in critical sites mediating deficient functions in the condition. The mechanisms for injury likely include altered perfusion and hypoxemia-induced processes, leading to acute tissue changes in recently diagnosed OSA.

Comparative evaluation of brain neurometabolites and DTI indices following whole body and cranial irradiation: a magnetic resonance imaging and spectroscopy study

Understanding early differential response of brain during whole body radiation or cranial radiation exposure is of significant importance for better injury management during accidental or intentional exposure to ionizing radiation. We investigated the early microstructural and metabolic profiles using in vivo diffusion tensor imaging (DTI) and proton magnetic resonance spectroscopy ((1)H MRS) following whole body and cranial radiation exposure of 8 Gy in mice using a 7.0 T animal MRI system and compared profiles with sham controls at days 1, 3, 5 and 10 post irradiation. A significant decrease in fractional anisotropy (FA) values was found in hippocampus, thalamic and hypothalamic regions (p < 0.05) in both whole body and cranial irradiated groups compared with controls, suggesting radiation induced reactive astrogliosis or neuroinflammatory response. In animals exposed to whole body radiation, FA was significantly decreased in some additional brain regions such as sensory motor cortex and corpus callosum in comparison with cranial irradiation groups and controls. Changes in FA were observed till day 10 post irradiation in both the groups. However, MRS study from hippocampus revealed changes only in the whole body radiation dose group. Significant reduction in the ratios of the metabolites myoinositol (mI, p = 0.02) and taurine (tau, p = 0.03) to total creatine were observed, and these metabolic alterations persisted till day 10 post irradiation. To the best of our knowledge this study has for the first time documented a comparative account of microstructural and metabolic aspects of whole body and cranial radiation induced early brain injury using in vivo MRI. Overall our findings suggest differential response at microstructure and metabolite levels following cranial or whole body radiation exposure.

Cartilage shear dynamics during tibio-femoral articulation: effect of acute joint injury and tribosupplementation on synovial fluid lubrication

OBJECTIVE

To determine the effects of acute injury and tribosupplementation by hyaluronan (HA) on synovial fluid (SF) modulation of cartilage shear during tibio-femoral articulation.

METHODS

Human osteochondral blocks from the lateral femoral condyle (LFC) and tibial plateau (LTP) were apposed, compressed 13%, and subjected to sliding under video microscopy. Tests were conducted with equine SF from normal joints (NL-SF), SF from acutely injured joints (AI-SF), and AI-SF to which HA was added (AI-SF+HA). Local and overall shear strain (E(xz)) and the lateral displacement (Deltax) at which E(xz) reached 50% of peak values (Deltax(1/2)) were determined.

RESULTS

During articulation, LFC and LTP cartilage E(xz) increased with Deltax and peaked when surfaces slid, with peak E(xz) being maintained during sliding. With AI-SF as lubricant, surface and overall Deltax(1/2) were approximately 40% and approximately 20% higher, respectively, than values with NL-SF and AI-SF+HA as lubricant. Also, peak E(xz) was markedly higher with AI-SF as lubricant than with NL-SF as lubricant, both near the surface (approximately 80%) and overall (50-200%). Following HA supplementation to AI-SF, E(xz) was reduced from values with AI-SF alone by 30-50% near the surface and 20-30% overall. Magnitudes of surface and overall E(xz) were markedly (approximately 50 to 80%) higher in LTP cartilage than LFC cartilage for all lubricants.

CONCLUSION

Acute injury impairs SF function, elevating cartilage E(xz) markedly during tibio-femoral articulation; such elevated E(xz) may contribute to post-injury associated cartilage degeneration. Since HA partially restores the function of AI-SF, as indicated by E(xz), tribosupplements may be beneficial in modulating normal cartilage homeostasis.

Gender differences in sport injury risk and types of inju-ries: a retrospective twelve-month study on cross-country skiers, swimmers, long-distance runners and soccer players

This twelve months survey compared injury risk and injury types by genders (312 females, 262 males) in 15- to 35-year-old cross-country skiers, swimmers, long- distance runners and soccer players. More male than female athletes reported at least one acute injury (44% vs. 35%, p < 0.05), and more male than female runners reported at least one overuse injury (69% vs. 51%, p < 0.05). When the incidence of acute and overuse injuries both separately and combined was calculated per 1000 training hours, per 1000 competition hours and all exposure hours combined we found no gender differences in either of these comparisons. After adjustment for sport event males were at increased risk for posterior thigh overuse injuries compared to females (relative risk (RR) 5.8, 95% confidence interval (CI) 1.3 to 26.4, p < 0.05) while females were at increased risk for overuse injuries in the ankle compared to males (RR 3.1, 95% CI 1.0 to 9.3, p < 0.05). After adjustment for exposure time (injuries/1000 exposure hours) significance of the difference between the sexes in overuse injury to the ankle persisted (female 0.11 vs. male 0.02 injuries/1000 exposure hours, p < 0.05). Six athletes had an anterior cruciate ligament (ACL) injury, of whom four were female soccer players. After combining all reported acute and overuse ankle and knee injuries, the proportion of athletes with such injury was higher in the female compared to male soccer players (75% and 54% respectively; p < 0.05), but no difference was found in such injuries when calculated per 1000 exposure hours. In conclusion, we found some gender differences in sport-related injuries, but most of these differences seemed to be explained at least in part by differences in the amount of training. Key pointsOnly a few sport injury studies have compared in-jury rates between the sexesOverall gender-related risk for acute and overuse injuries in top-level athletes between the sexes was smallSome gender differences in the specific anatomical locations of injuries as well as in specific injuries in sports were foundSome of these differences seem to be explained by the differences in the amount of training.

Secondary injury after musculoskeletal trauma: a review and update

OBJECTIVES

To revisit the secondary injury model, to incorporate several current pathophysiologic theories into the model, and to show the need for more direct research examining the model.

DATA SOURCES

I searched MEDLINE and CINAHL from 1976 to 2001 for literature related to acute injury pathology and pathophysiology and selected classic articles and pathology, pathophysiology, and immunology texts.

DATA SYNTHESIS

Acute musculoskeletal injury management is based on a pathophysiologic model, often referred to as the secondary injury model, which was originally developed more than 25 years ago. In this model, acute trauma is referred to as primary injury, whereas secondary injury refers to damage to otherwise uninjured cells that was a direct consequence of the physiologic response to primary injury. In the original model, mechanisms for secondary injury were hypothesized based on then-contemporary understandings of immunology and cellular pathology. These mechanisms were broadly categorized as either enzymatic or hypoxic. Since this time, the pathologic paradigms for cell death from trauma have evolved, and the secondary injury model requires some updating. Some controversy now exists regarding the categorization of injury as primary or secondary, specifically whether posttraumatic damage is actually secondary injury in previously uninjured tissue or delayed death of primary injured cells. Similarly, the postulated mechanisms that lead to secondary injury now appear to be considerably more complex than originally anticipated.

CONCLUSIONS/RECOMMENDATIONS

The secondary injury model has been reconciled with our contemporary understanding of pathophysiology. Specifically, secondary hypoxic injury has been clarified to be secondary ischemic injury, and several specific mechanisms for ischemic injury have been identified. Similarly, secondary injury from mitochondrial failure and other potential mechanisms has been identified, and the role and interaction of these mechanisms in relation to total secondary injury have been expanded.

The role of nonsteroidal anti-inflammatory drugs in the treatment of acute soft tissue injuries

OBJECTIVE

Nonsteroidal anti-inflammatory drugs (NSAIDs) are frequently used to hasten the return of injured athletes to competition after injury. Evidence demonstrates that while NSAIDs may speed recovery after acute soft tissue injuries, long-term healing may be compromised. This review aims to assess the effects of NSAIDs on inflammation and healing associated with acute soft tissue injury.

DATA SOURCES

CINAHL (1982 to 1997), SPORT Discus (1977 to 1997), and MEDLINE (1993 to 1997) were searched using the keywords "NSAIDs," "musculoskeletal," "acute," "sprain," and ";strain."

DATA SYNTHESIS

NSAIDs exhibit anti-inflammatory effects via prostaglandin inhibition, neutrophil migration suppression, and oxygen free-radical inhibition. Retardation of inflammatory processes after acute injury may limit the area of secondary tissue damage but may also retard healing. Animal models have demonstrated short-term benefits with NSAIDs after acute injury, along with long-term adverse effects on tissue structure and function. NSAIDs have exhibited few benefits in the treatment of delayed-onset muscle soreness. Clinical trials of NSAIDs in the treatment of acute soft tissue injuries have shown conflicting results and have been highly criticized.

CONCLUSIONS/RECOMMENDATIONS

Based on the research literature, the short-term benefits of NSAIDs in the treatment of acute soft tissue injuries must be weighed against the potential long-term adverse effects on tissue healing, structure, and function.