The impact of post-operative enteral nutrition on duodenal injury outcomes: A post hoc analysis of an EAST multicenter trial.

BACKGROUND: Leak following surgical repair of traumatic duodenal injuries results in prolonged hospitalization and oftentimes nil per os(NPO) treatment. Parenteral nutrition(PN) has known morbidity; however, duodenal leak(DL) patients often have complex injuries and hospital courses resulting in barriers to enteral nutrition(EN). We hypothesized EN alone would be associated with 1)shorter duration until leak closure and 2)less infectious complications and shorter hospital length of stay(HLOS) compared to PN. METHODS: This was a post-hoc analysis of a retrospective, multicenter study from 35 Level-1 trauma centers, including patients >14 years-old who underwent surgery for duodenal injuries(1/2010-12/2020) and endured post-operative DL. The study compared nutrition strategies: EN vs PN vs EN + PN using Chi-Square and Kruskal-Wallis tests; if significance was found pairwise comparison or Dunn's test were performed. RESULTS: There were 113 patients with DL: 43 EN, 22 PN, and 48 EN + PN. Patients were young(median age 28 years-old) males(83.2%) with penetrating injuries(81.4%). There was no difference in injury severity or critical illness among the groups, however there were more pancreatic injuries among PN groups. EN patients had less days NPO compared to both PN groups(12 days[IQR23] vs 40[54] vs 33[32],p = <0.001). Time until leak closure was less in EN patients when comparing the three groups(7 days[IQR14.5] vs 15[20.5] vs 25.5[55.8],p = 0.008). EN patients had less intra-abdominal abscesses, bacteremia, and days with drains than the PN groups(all p < 0.05). HLOS was shorter among EN patients vs both PN groups(27 days[24] vs 44[62] vs 45[31],p = 0.001). When controlling for predictors of leak, regression analysis demonstrated EN was associated with shorter HLOS(ß -24.9, 95%CI -39.0 to -10.7,p < 0.001). CONCLUSION: EN was associated with a shorter duration until leak closure, less infectious complications, and shorter length of stay. Contrary to some conventional thought, PN was not associated with decreased time until leak closure. We therefore suggest EN should be the preferred choice of nutrition in patients with duodenal leaks whenever feasible. LEVEL OF EVIDENCE: IV.

Bone Anchor Fixation in the Repair of Blunt Traumatic Abdominal Wall Hernias: A Western Trauma Association Multicenter Study.

BACKGROUND: Blunt traumatic abdominal wall hernias (TAWHs) are rare but require a variety of operative techniques to repair including bone anchor fixation (BAF) when tissue tears off bony structures. This study aimed to provide a descriptive analysis of BAF technique for blunt TAWH repair. Bone anchor fixation and no BAF repairs were compared, hypothesizing increased hernia recurrence with BAF repair. METHODS: A secondary analysis of the WTA blunt TAWH multicenter study was performed including all patients who underwent repair of their TAWH. Patients with BAF were compared to those with no BAF with bivariate analyses. RESULTS: 176 patients underwent repair of their TAWH with 41 (23.3%) undergoing BAF. 26 (63.4%) patients had tissue fixed to bone, with 7 of those reinforced with mesh. The remaining 15 (36.6%) patients had bridging mesh anchored to bone. The BAF group had a similar age, sex, body mass index, and injury severity score compared to the no BAF group. The time to repair (1 vs 1 days, P = .158), rate of hernia recurrence (9.8% vs 12.7%, P = .786), and surgical site infection (SSI) (12.5% vs 15.6%, P = .823) were all similar between cohorts. CONCLUSIONS: This largest series to date found nearly one-quarter of TAWH repairs required BAF. Bone anchor fixation repairs had a similar rate of hernia recurrence and SSI compared to no BAF repairs, suggesting this is a reasonable option for repair of TAWH. However, future prospective studies are needed to compare specific BAF techniques and evaluate long-term outcomes including patient-centered outcomes such as pain and quality of life.

Warfarin, not direct oral anticoagulants nor antiplatelet therapy, is associated with increased bleeding risk in emergency general surgery patients: implications in this new era of novel anticoagulants: An EAST Multicenter study.

INTRODUCTION: To assess perioperative bleeding complications & in-hospital mortality in patients requiring emergency general surgery (EGS) presenting with a history of antiplatelet (AP) vs. direct oral anticoagulant (DOAC) vs warfarin use. METHODS: Prospective observational study across 21 centers between 2019-2022. Inclusion criteria were age ≥ 18 years, & DOAC, warfarin or AP use within 24 hours of an EGSP. Outcomes included perioperative bleeding and in-hospital mortality. The study was conducted using ANOVA, Chi-square, and multivariable regression models. RESULTS: Of the 413 patients, 221 (53.5%) reported AP use, 152 (36.8%) DOAC use, & 40 (9.7%) warfarin use. Most common indications for surgery were obstruction (23% (AP), 45% (DOAC), 28% (warfarin)), intestinal ischemia (13%, 17%, 23%), & diverticulitis/peptic ulcers (7%, 7%, 15%). Compared to DOAC use, warfarin use was associated with significantly higher perioperative bleeding complication (OR 4.4 [2.0, 9.9]). There was no significant difference in perioperative bleeding complication between DOAC & AP use (OR 0.7 [0.4, 1.1]). Compared to DOAC use, there was no significant difference in mortality between warfarin use (0.7 [0.2, 2.5]) or AP use (OR 0.5 [0.2, 1.2]). After adjusting for confounders, warfarin use (OR 6.3 [2.8, 13.9]), medical history and operative indication were associated with an increase in perioperative bleeding complications. However, warfarin was not independently associated with risk of mortality (OR 1.3 [0.39, 4.7]), whereas intraoperative vasopressor use (OR 4.7 [1.7, 12.8)), medical history & postoperative bleeding (OR 5.5 [2.4, 12.8]) were. CONCLUSIONS: Despite ongoing concerns about the increase in DOAC use & lack of readily available reversal agents, this study suggests that warfarin, rather than DOACs, is associated with higher perioperative bleeding complications. However, that risk does not result in an increase in mortality, suggesting that perioperative decisions should be dictated by patient disease & comorbidities rather than type of antiplatelet or anticoagulant use.

CHRFAM7A diversifies human immune adaption through Ca2+ signalling and actin cytoskeleton reorganization.

BACKGROUND: Human restricted genes contribute to human specific traits in the immune system. CHRFAM7A, a uniquely human fusion gene, is a negative regulator of the α7 nicotinic acetylcholine receptor (α7 nAChR), the highest Ca2+ conductor of the ACh receptors implicated in innate immunity. Understanding the mechanism of how CHRFAM7A affects the immune system remains unexplored. METHODS: Two model systems are used, human induced pluripotent stem cells (iPSC) and human primary monocytes, to characterize α7 nAChR function, Ca2+ dynamics and decoders to elucidate the pathway from receptor to phenotype. FINDINGS: CHRFAM7A/α7 nAChR is identified as a hypomorphic receptor with mitigated Ca2+ influx and prolonged channel closed state. This shifts the Ca2+ reservoir from the extracellular space to the endoplasmic reticulum (ER) leading to Ca2+ dynamic changes. Ca2+ decoder small GTPase Rac1 is then activated, reorganizing the actin cytoskeleton. Observed actin mediated phenotypes include cellular adhesion, motility, phagocytosis and tissue mechanosensation. INTERPRETATION: CHRFAM7A introduces an additional, human specific, layer to Ca2+ regulation leading to an innate immune gain of function. Through the actin cytoskeleton it drives adaptation to the mechanical properties of the tissue environment leading to an ability to invade previously immune restricted niches. Human genetic diversity predicts profound translational significance as its understanding builds the foundation for successful treatments for infectious diseases, sepsis, and cancer metastasis. FUNDING: This work is supported in part by the Community Foundation for Greater Buffalo (Kinga Szigeti) and in part by NIH grant R01HL163168 (Yongho Bae).

Failure rates of nonoperative management of low-grade splenic injuries with active extravasation: an Eastern Association for the Surgery of Trauma multicenter study.

Objectives: There is little evidence guiding the management of grade I-II traumatic splenic injuries with contrast blush (CB). We aimed to analyze the failure rate of nonoperative management (NOM) of grade I-II splenic injuries with CB in hemodynamically stable patients. Methods: A multicenter, retrospective cohort study examining all grade I-II splenic injuries with CB was performed at 21 institutions from January 1, 2014, to October 31, 2019. Patients >18 years old with grade I or II splenic injury due to blunt trauma with CB on CT were included. The primary outcome was the failure of NOM requiring angioembolization/operation. We determined the failure rate of NOM for grade I versus grade II splenic injuries. We then performed bivariate comparisons of patients who failed NOM with those who did not. Results: A total of 145 patients were included. Median Injury Severity Score was 17. The combined rate of failure for grade I-II injuries was 20.0%. There was no statistical difference in failure of NOM between grade I and II injuries with CB (18.2% vs 21.1%, p>0.05). Patients who failed NOM had an increased median hospital length of stay (p=0.024) and increased need for blood transfusion (p=0.004) and massive transfusion (p=0.030). Five patients (3.4%) died and 96 (66.2%) were discharged home, with no differences between those who failed and those who did not fail NOM (both p>0.05). Conclusion: NOM of grade I-II splenic injuries with CB fails in 20% of patients. Level of evidence: IV.

Advancing health equity in improving breast cancer screening with the use of a mobile mammography bus in marginalised population: quality improvement project.

BACKGROUND: Breast cancer, the second leading cause of cancer-related deaths in women in the USA, is effectively treated through early detection and screening. This quality improvement (QI) project aimed to improve mammography screening rates from the baseline of 50% to 60% within 12 months for patients aged 50-74 years at an Internal Medicine Clinic. METHODS: We used the Plan, Do, Study, Act (PDSA) model. A multidisciplinary team used a fishbone diagram to identify barriers to suboptimal screening. The QI team created a driver diagram and process flow map. The mammogram screening rate was the outcome measure. Mammogram order and completion rates were the process measures. We implemented six PDSA cycles. Major interventions included the use of a nurse navigator, enhancements in health information technology, and education to patients, providers, and nursing staff. Mammograms were offered in a mobile bus, located in the hospital campus and in under-resourced inner-city neighbourhoods to improve the access. Data analysis was performed using monthly statistical process control charts. RESULTS: The project exceeded its initial goal, achieving a breast cancer screening rate of 66% (n=490 of 744) during the study period and was sustainable at 69%, 3 months post-project. The mammogram order rate was 58% (n=432 of 744) and completion rate was 53% (n=231 of 432) within 12 months. CONCLUSIONS: We attributed the success of this QI project to the education of patients, nurses and physicians, the use of a nurse navigator and engagement of a multidisciplinary team. Access to mobile mammography bus addressed the social determinants of health barriers in a marginalised population.

A western trauma association multicenter comparison of mesh versus non-mesh repair of blunt traumatic abdominal wall hernias.

BACKGROUND: Blunt traumatic abdominal wall hernias (TAWH) occur in <1 % of trauma patients. Optimal repair techniques, such as mesh reinforcement, have not been studied in detail. We hypothesize that mesh use will be associated with increased surgical site infections (SSI) and not improve hernia recurrence. MATERIALS AND METHODS: A secondary analysis of the Western Trauma Association blunt TAWH multicenter study was performed. Patients who underwent TAWH repair during initial hospitalization (1/2012-12/2018) were included. Mesh repair patients were compared to primary repair patients (non-mesh). A logistic regression was conducted to assess risk factors for SSI. RESULTS: 157 patients underwent TAWH repair during index hospitalization with 51 (32.5 %) having mesh repair: 24 (45.3 %) synthetic and 29 (54.7 %) biologic. Mesh patients were more commonly smokers (43.1 % vs. 22.9 %, p = 0.016) and had a larger defect size (10 vs. 6 cm, p = 0.003). Mesh patients had a higher rate of SSI (25.5 % vs. 9.5 %, p = 0.016) compared to non-mesh patients, but a similar rate of recurrence (13.7 % vs. 10.5%, p = 0.742), hospital length of stay (LOS), and mortality. Mesh use (OR 3.66) and higher ISS (OR 1.06) were significant risk factors for SSI in a multivariable model. CONCLUSION: Mesh was used more frequently in flank TAWH and those with a larger defect size. Mesh use was associated with a higher incidence and risk of SSI but did not reduce the risk of hernia recurrence. When repairing TAWH mesh should be employed judiciously, and prospective randomized studies are needed to identify clear indications for mesh use in TAWH.

Mutate and Conjugate: A Method to Enable Rapid In-Cell Target Validation.

Target validation remains a challenge in drug discovery, which leads to a high attrition rate in the drug discovery process, particularly in Phase II clinical trials. Consequently, new approaches to enhance target validation are valuable tools to improve the drug discovery process. Here, we report the combination of site-directed mutagenesis and electrophilic fragments to enable the rapid identification of small molecules that selectively inhibit the mutant protein. Using the bromodomain-containing protein BRD4 as an example, we employed a structure-based approach to identify the L94C mutation in the first bromodomain of BRD4 [BRD4(1)] as having a minimal effect on BRD4(1) function. We then screened a focused, KAc mimic-containing fragment set and a diverse fragment library against the mutant and wild-type proteins and identified a series of fragments that showed high selectivity for the mutant protein. These compounds were elaborated to include an alkyne click tag to enable the attachment of a fluorescent dye. These clickable compounds were then assessed in HEK293T cells, transiently expressing BRD4(1)WT or BRD4(1)L94C, to determine their selectivity for BRD4(1)L94C over other possible cellular targets. One compound was identified that shows very high selectivity for BRD4(1)L94C over all other proteins. This work provides a proof-of-concept that the combination of site-directed mutagenesis and electrophilic fragments, in a mutate and conjugate approach, can enable rapid identification of small molecule inhibitors for an appropriately mutated protein of interest. This technology can be used to assess the cellular phenotype of inhibiting the protein of interest, and the electrophilic ligand provides a starting point for noncovalent ligand development.

Model discovery approach enables non-invasive measurement of intra-tumoral fluid transport in dynamic MRI.

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is a routine method to non-invasively quantify perfusion dynamics in tissues. The standard practice for analyzing DCE-MRI data is to fit an ordinary differential equation to each voxel. Recent advances in data science provide an opportunity to move beyond existing methods to obtain more accurate measurements of fluid properties. Here, we developed a localized convolutional function regression that enables simultaneous measurement of interstitial fluid velocity, diffusion, and perfusion in 3D. We validated the method computationally and experimentally, demonstrating accurate measurement of fluid dynamics in situ and in vivo. Applying the method to human MRIs, we observed tissue-specific differences in fluid dynamics, with an increased fluid velocity in breast cancer as compared to brain cancer. Overall, our method represents an improved strategy for studying interstitial flows and interstitial transport in tumors and patients. We expect that it will contribute to the better understanding of cancer progression and therapeutic response.

Does lower extremity fracture fixation technique influence neurologic outcomes in patients with traumatic brain injury? The EAST Brain vs. Bone multicenter trial.

OBJECTIVE: This study aimed to determine whether lower extremity fracture fixation technique and timing (≤24 vs. >24 hours) impact neurologic outcomes in TBI patients. METHODS: A prospective observational study was conducted across 30 trauma centers. Inclusion criteria were age 18 years and older, head Abbreviated Injury Scale (AIS) score of >2, and a diaphyseal femur or tibia fracture requiring external fixation (Ex-Fix), intramedullary nailing (IMN), or open reduction and internal fixation (ORIF). The analysis was conducted using analysis of variamce, Kruskal-Wallis, and multivariable regression models. Neurologic outcomes were measured by discharge Ranchos Los Amigos Revised Scale (RLAS-R). RESULTS: Of the 520 patients enrolled, 358 underwent Ex-Fix, IMN, or ORIF as definitive management. Head AIS was similar among cohorts. The Ex-Fix group experienced more severe lower extremity injuries (AIS score, 4-5) compared with the IMN group (16% vs. 3%, p = 0.01) but not the ORIF group (16% vs. 6%, p = 0.1). Time to operative intervention varied between the cohorts with the longest time to intervention for the IMN group (median hours: Ex-Fix, 15 [8-24] vs. ORIF, 26 [12-85] vs. IMN, 31 [12-70]; p < 0.001). The discharge RLAS-R score distribution was similar across the groups. After adjusting for confounders, neither method nor timing of lower extremity fixation influenced the discharge RLAS-R. Instead, increasing age and head AIS score were associated with a lower discharge RLAS-R score (odds ratio [OR], 1.02; 95% confidence interval [CI], 1.002-1.03 and OR, 2.37; 95% CI, 1.75-3.22), and a higher Glasgow Coma Scale motor score on admission (OR, 0.84; 95% CI, 0.73-0.97) was associated with higher RLAS-R score at discharge. CONCLUSION: Neurologic outcomes in TBI are impacted by severity of the head injury and not the fracture fixation technique or timing. Therefore, the strategy of definitive fixation of lower extremity fractures should be dictated by patient physiology and the anatomy of the injured extremity and not by the concern for worsening neurologic outcomes in TBI patients. LEVEL OF EVIDENCE: Prognostic and Epidemiological; Level III.

An immunoregulator nanomedicine approach for the treatment of tuberculosis.

Introduction: A nanoparticle composed of a poly (lactic-co-glycolic acid) (PLGA) core and a chitosan (CS) shell with surface-adsorbed 1,3 ß-glucan (ß-glucan) was synthesized. The exposure response of CS-PLGA nanoparticles (0.1 mg/mL) with surface-bound ß-glucan at 0, 5, 10, 15, 20, or 25 ng or free ß-glucan at 5, 10, 15, 20, or 25 ng/mL in macrophage in vitro and in vivo was investigated. Results: In vitro studies demonstrate that gene expression for IL-1ß, IL-6, and TNFα increased at 10 and 15 ng surface-bound ß-glucan on CS-PLGA nanoparticles (0.1 mg/mL) and at 20 and 25 ng/mL of free ß-glucan both at 24 h and 48 h. Secretion of TNFα protein and ROS production increased at 5, 10, 15, and 20 ng surface-bound ß-glucan on CS-PLGA nanoparticles and at 20 and 25 ng/mL of free ß-glucan at 24 h. Laminarin, a Dectin-1 antagonist, prevented the increase in cytokine gene expression induced by CS-PLGA nanoparticles with surface-bound ß-glucan at 10 and 15 ng, indicating a Dectin-1 receptor mechanism. Efficacy studies showed a significant reduction in intracellular accumulation of mycobacterium tuberculosis (Mtb) in monocyte-derived macrophages (MDM) incubated with on CS-PLGA (0.1 mg/ml) nanoparticles with 5, 10, and 15 ng surface-bound ß-glucan or with 10 and 15 ng/mL of free ß-glucan. ß-glucan-CS-PLGA nanoparticles inhibited intracellular Mtb growth more than free ß-glucan alone supporting the role of ß-glucan-CS-PLGA nanoparticles as stronger adjuvants than free ß-glucan. In vivo studies demonstrate that oropharyngeal aspiration (OPA) of CS-PLGA nanoparticles with nanogram concentrations of surface-bound ß-glucan or free ß-glucan increased TNFα gene expression in alveolar macrophages and TNFα protein secretion in bronchoalveolar lavage supernatants. Discussion: Data also demonstrate no damage to the alveolar epithelium or changes in the murine sepsis score following exposure to ß-glucan-CS-PLGA nanoparticles only, indicating safety and feasibility of this nanoparticle adjuvant platform to mice by OPA.

Anticoagulation in emergency general surgery: Who bleeds more? The EAST multicenter trials ACES study.

BACKGROUND: While direct oral anticoagulant (DOAC) use is increasing in the Emergency General Surgery (EGS) patient population, our understanding of their bleeding risk in the acute setting remains limited. Therefore, the objective of this study was to determine the prevalence of perioperative bleeding complications in patients using DOACs versus warfarin and AP therapy requiring urgent/emergent EGS procedures (EGSPs). METHODS: This was a prospective observational trial, conducted between 2019 and 2022, across 21 centers. Inclusion criteria were 18 years or older, DOAC, warfarin/AP use within 24 hours of requiring an urgent/emergent EGSP. Demographics, preoperative, intraoperative, and postoperative data were collected. ANOVA, χ 2 , and multivariable regression models were used to conduct the analysis. RESULTS: Of the 413 patients enrolled in the study, 261 (63%) reported warfarin/AP use and 152 (37%) reported DOAC use. Appendicitis and cholecystitis were the most frequent indication for operative intervention in the warfarin/AP group (43.4% vs. 25%, p = 0.001). Small bowel obstruction/abdominal wall hernias were the main indication for operative intervention in the DOAC group (44.7% vs. 23.8%, p = 0.001). Intraoperative, postoperative, and perioperative bleeding complications and in-hospital mortality were similar between the two groups. After adjusting for confounders, a history of chemotherapy (odds ratio [OR], 4.3; p = 0.015) and indication for operative intervention including occlusive mesenteric ischemia (OR, 4.27; p = 0.016), nonocclusive mesenteric ischemia (OR, 3.13; p = 0.001), and diverticulitis (OR, 3.72; p = 0.019) were associated with increased perioperative bleeding complications. The need for an intraoperative transfusion (OR, 4.87; p < 0.001), and intraoperative vasopressors (OR, 4.35; p = 0.003) were associated with increased in-hospital mortality. CONCLUSION: Perioperative bleeding complications and mortality are impacted by the indication for EGSPs and patient's severity of illness rather than a history of DOAC or warfarin/AP use. Therefore, perioperative management should be guided by patient physiology and indication for surgery rather than the concern for recent antiplatelet or anticoagulant use. LEVEL OF EVIDENCE: Prognostic and Epidemiologic; Level III.

Outcomes among trauma patients with duodenal leak following primary versus complex repair of duodenal injuries: An Eastern Association for the Surgery of Trauma multicenter trial.

BACKGROUND: Duodenal leak is a feared complication of repair, and innovative complex repairs with adjunctive measures (CRAM) were developed to decrease both leak occurrence and severity when leaks occur. Data on the association of CRAM and duodenal leak are sparse, and its impact on duodenal leak outcomes is nonexistent. We hypothesized that primary repair alone (PRA) would be associated with decreased duodenal leak rates; however, CRAM would be associated with improved recovery and outcomes when leaks do occur. METHODS: A retrospective, multicenter analysis from 35 Level 1 trauma centers included patients older than 14 years with operative, traumatic duodenal injuries (January 2010 to December 2020). The study sample compared duodenal operative repair strategy: PRA versus CRAM (any repair plus pyloric exclusion, gastrojejunostomy, triple tube drainage, duodenectomy). RESULTS: The sample (N = 861) was primarily young (33 years) men (84%) with penetrating injuries (77%); 523 underwent PRA and 338 underwent CRAM. Complex repairs with adjunctive measures were more critically injured than PRA and had higher leak rates (CRAM 21% vs. PRA 8%, p < 0.001). Adverse outcomes were more common after CRAM with more interventional radiology drains, prolonged nothing by mouth and length of stay, greater mortality, and more readmissions than PRA (all p < 0.05). Importantly, CRAM had no positive impact on leak recovery; there was no difference in number of operations, drain duration, nothing by mouth duration, need for interventional radiology drainage, hospital length of stay, or mortality between PRA leak versus CRAM leak patients (all p > 0.05). Furthermore, CRAM leaks had longer antibiotic duration, more gastrointestinal complications, and longer duration until leak resolution (all p < 0.05). Primary repair alone was associated with 60% lower odds of leak, whereas injury grades II to IV, damage control, and body mass index had higher odds of leak (all p < 0.05). There were no leaks among patients with grades IV and V injuries repaired by PRA. CONCLUSION: Complex repairs with adjunctive measures did not prevent duodenal leaks and, moreover, did not reduce adverse sequelae when leaks did occur. Our results suggest that CRAM is not a protective operative duodenal repair strategy, and PRA should be pursued for all injury grades when feasible. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level IV.

Risk factors for recurrence in blunt traumatic abdominal wall hernias: A secondary analysis of a Western Trauma association multicenter study.

BACKGROUND: Few studies have investigated risk factors for recurrence of blunt traumatic abdominal wall hernias (TAWH). METHODS: Twenty trauma centers identified repaired TAWH from January 2012 to December 2018. Logistic regression was used to investigate risk factors for recurrence. RESULTS: TAWH were repaired in 175 patients with 21 (12.0%) known recurrences. No difference was found in location, defect size, or median time to repair between the recurrence and non-recurrence groups. Mesh use was not protective of recurrence. Female sex, injury severity score (ISS), emergency laparotomy (EL), and bowel resection were associated with hernia recurrence. Bowel resection remained significant in a multivariable model. CONCLUSION: Female sex, ISS, EL, and bowel resection were identified as risk factors for hernia recurrence. Mesh use and time to repair were not associated with recurrence. Surgeons should be mindful of these risk factors but could attempt acute repair in the setting of appropriate physiologic parameters.

Identification of Histone Peptide Binding Specificity and Small-Molecule Ligands for the TRIM33α and TRIM33ß Bromodomains.

TRIM33 is a member of the tripartite motif (TRIM) family of proteins, some of which possess E3 ligase activity and are involved in the ubiquitin-dependent degradation of proteins. Four of the TRIM family proteins, TRIM24 (TIF1α), TRIM28 (TIF1ß), TRIM33 (TIF1γ) and TRIM66, contain C-terminal plant homeodomain (PHD) and bromodomain (BRD) modules, which bind to methylated lysine (KMen) and acetylated lysine (KAc), respectively. Here we investigate the differences between the two isoforms of TRIM33, TRIM33α and TRIM33ß, using structural and biophysical approaches. We show that the N1039 residue, which is equivalent to N140 in BRD4(1) and which is conserved in most BRDs, has a different orientation in each isoform. In TRIM33ß, this residue coordinates KAc, but this is not the case in TRIM33α. Despite these differences, both isoforms show similar affinities for H31-27K18Ac, and bind preferentially to H31-27K9Me3K18Ac. We used this information to develop an AlphaScreen assay, with which we have identified four new ligands for the TRIM33 PHD-BRD cassette. These findings provide fundamental new information regarding which histone marks are recognized by both isoforms of TRIM33 and suggest starting points for the development of chemical probes to investigate the cellular function of TRIM33.

Emergent and urgent ventral hernia repair: comparing recurrence rates amongst procedures utilizing mesh versus no mesh.

BACKGROUND: The decision for emergent and urgent ventral hernia repair (VHR) is driven by acute symptomatology, concern for incarceration and strangulation, and perforation. Although mesh has been established to reduce hernia recurrences, the potential for mesh complications may impact the decision for utilization in emergent repairs. This study evaluates hernia repair outcomes in the emergent setting with/without mesh. METHODS: An IRB-approved review of NSQIP and retrospective chart review data of emergent/urgent VHRs performed between 2013 and 2017 was conducted at a single academic institution. Six-month postoperative emergency department and surgery clinic visits, hospital readmissions, and hernia recurrences were recorded. Patients were grouped based on mesh utilization. Perioperative and outcome variables were compared using Chi-square, Fisher's exact, and t-tests. RESULTS: Among 94 patients, 41 (44%) received mesh; 53 (56%) did not. Synthetic mesh was used in 27 cases (65.9%); bioresorbable or biologic mesh was used in 14 cases (34.1%). ASA class (p = 0.016) was higher in the no-mesh group, as were emergent vs. urgent cases (p ≤ 0.001). Preoperative SIRS/Sepsis, COPD, and diabetes were increased in the no-mesh group. Hernia recurrence was significantly higher in the no-mesh group vs. the mesh group (24.5% vs. 7.3%, p = 0.03). No difference was found in wound complications between groups. ED visits occurred almost twice as often in the mesh group (42% vs. 23%, p = 0.071). Postoperative surgery clinic visits were more frequent among the mesh group (> 1 visit 61% vs. 24%, p = 0.004). CONCLUSIONS: Mesh-based hernia repairs in the urgent/emergent patient population are performed in fewer than half of patients in our tertiary care referral center. Repairs without mesh were associated with over a three-fold increase in recurrence without a difference in the risk of infectious complications. Efforts to understand the rationale for suture-based repair compared to mesh repair are needed to reduce hernia recurrences in the emergent population.

Mitochondrial Dynamics in SARS-COV2 Spike Protein Treated Human Microglia: Implications for Neuro-COVID.

Emerging clinical data from the current COVID-19 pandemic suggests that ~ 40% of COVID-19 patients develop neurological symptoms attributed to viral encephalitis while in COVID long haulers chronic neuro-inflammation and neuronal damage result in a syndrome described as Neuro-COVID. We hypothesize that SAR-COV2 induces mitochondrial dysfunction and activation of the mitochondrial-dependent intrinsic apoptotic pathway, resulting in microglial and neuronal apoptosis. The goal of our study was to determine the effect of SARS-COV2 on mitochondrial biogenesis and to monitor cell apoptosis in human microglia non-invasively in real time using Raman spectroscopy, providing a unique spatio-temporal information on mitochondrial function in live cells. We treated human microglia with SARS-COV2 spike protein and examined the levels of cytokines and reactive oxygen species (ROS) production, determined the effect of SARS-COV2 on mitochondrial biogenesis and examined the changes in molecular composition of phospholipids. Our results show that SARS- COV2 spike protein increases the levels of pro-inflammatory cytokines and ROS production, increases apoptosis and increases the oxygen consumption rate (OCR) in microglial cells. Increases in OCR are indicative of increased ROS production and oxidative stress suggesting that SARS-COV2 induced cell death. Raman spectroscopy yielded significant differences in phospholipids such as Phosphatidylinositol (PI), phosphatidylserine (PS), phosphatidylethanolamine (PE) and phosphatidylcholine (PC), which account for ~ 80% of mitochondrial membrane lipids between SARS-COV2 treated and untreated microglial cells. These data provide important mechanistic insights into SARS-COV2 induced mitochondrial dysfunction which underlies neuropathology associated with Neuro-COVID.

Management of blunt traumatic abdominal wall hernias: A Western Trauma Association multicenter study.

BACKGROUND: Blunt traumatic abdominal wall hernias (TAWH) occur in approximately 15,000 patients per year. Limited data are available to guide the timing of surgical intervention or the feasibility of nonoperative management. METHODS: A retrospective study of patients presenting with blunt TAWH from January 2012 through December 2018 was conducted. Patient demographic, surgical, and outcomes data were collected from 20 institutions through the Western Trauma Association Multicenter Trials Committee. RESULTS: Two hundred and eighty-one patients with TAWH were identified. One hundred and seventy-six (62.6%) patients underwent operative hernia repair, and 105 (37.4%) patients underwent nonoperative management. Of those undergoing surgical intervention, 157 (89.3%) were repaired during the index hospitalization, and 19 (10.7%) underwent delayed repair. Bowel injury was identified in 95 (33.8%) patients with the majority occurring with rectus and flank hernias (82.1%) as compared with lumbar hernias (15.8%). Overall hernia recurrence rate was 12.0% (n = 21). Nonoperative patients had a higher Injury Severity Score (24.4 vs. 19.4, p = 0.010), head Abbreviated Injury Scale score (1.1 vs. 0.6, p = 0.006), and mortality rate (11.4% vs. 4.0%, p = 0.031). Patients who underwent late repair had lower rates of primary fascial repair (46.4% vs. 77.1%, p = 0.012) and higher rates of mesh use (78.9% vs. 32.5%, p < 0.001). Recurrence rate was not statistically different between the late and early repair groups (15.8% vs. 11.5%, p = 0.869). CONCLUSION: This report is the largest series and first multicenter study to investigate TAWHs. Bowel injury was identified in over 30% of TAWH cases indicating a significant need for immediate laparotomy. In other cases, operative management may be deferred in specific patients with other life-threatening injuries, or in stable patients with concern for bowel injury. Hernia recurrence was not different between the late and early repair groups. LEVEL OF EVIDENCE: Therapeutic/care management, Level IV.