A Modified Cell-Penetrating Peptide Enhances Insulin and Oxytocin Delivery across an RPMI 2650 Nasal Epithelial Cell Barrier In Vitro.

Background/Objectives: Peptide-based treatments represent an expanding area and require innovative approaches to enhance bioavailability. Combination with cell-penetrating peptides (CPPs) is an attractive strategy to improve non-invasive delivery across nasal epithelial barriers for systemic and direct nose-to-brain transport. We previously developed a modified CPP system termed Glycosaminoglycan-binding Enhanced Transduction (GET) that improves insulin delivery across gastrointestinal epithelium. It contains a membrane docking sequence to promote cellular interactions (P21), a cationic polyarginine domain to stimulate uptake (8R) and an endosomal escaping sequence to maximize availability for onward distribution (LK15). It is synthesized as a single 44-residue peptide (P21-LK15-8R; PLR). METHODS: The current research used in vitro assays for a novel exploration of PLR's ability to improve the transport of two contrasting peptides, insulin (51 residues, net negative charge) and oxytocin (9 residues, weak positive charge) across an RPMI 2650 human nasal epithelial cell barrier cultured at the air-liquid interface. RESULTS: PLR enhanced insulin transcytosis over a 6 h period by 7.8-fold when used at a 2:1 molar ratio of insulin/PLR (p < 0.0001 versus insulin alone). Enhanced oxytocin transcytosis (5-fold) occurred with a 1:10 ratio of oytocin/PLR (p < 0.01). Importantly, these were independent of any impact on transepithelial electrical resistance (TEER) or cell viability (p > 0.05). CONCLUSIONS: We advocate the continued evaluation of insulin-PLR and oxytocin-PLR formulations, including longer-term assessments of ciliotoxicity and cytotoxicity in vitro followed by in vivo assessments of systemic and nose-to-brain delivery.

Synthesis and reduction of [(C5H4SiMe3)2Ln(µ-OR)]2 (Ln = La, Ce) complexes: structural effects of bridging alkoxides.

Alcoholysis of Cp'3Ln (Ln = La, Ce; Cp' = C5H4SiMe3) generate high-yielding (72-97%) bimetallic LnIII complexes of [Cp'2Ln(µ-OR)]2 [R = Et, iPr, or C6H4-4-tBu]. Single-crystal X-ray diffraction of these complexes reveal unexpected decreases in Ln⋯Ln distances, increasing Cpcent-Ln-Cpcent angles, and increasing intermolecular C⋯C contacts with bulkier bridging alkoxides, in line with structural control driven by significant dispersion forces. 1H NMR spectroscopy of [Cp'2Ce(µ-OEt)]2 and [Cp'2Ce(µ-OiPr)]2 revealed significantly upfield resonances assigned as methylene and methine moieties of -43.74 and -70.85 ppm, respectively. 2D 1H DOSY NMR experiments of [Cp'2Ce(µ-OiPr)]2 in C6D6 supported a dimeric structure in solution, including in the presence of a Lewis base (i.e., THF). Reduction of [Cp'2La(µ-OiPr)]2 using KC8 in the presence of 2.2.2-cryptand at -78 °C generated a purple solution and X-band EPR spectroscopy revealed an eight-line hyperfine pattern indicative of a LaII species.

MHC heterozygosity limits T cell receptor variability in CD4 T cells.

αß T cell receptor (TCR) V(D)J genes code for billions of TCR combinations. However, only some appear on peripheral T cells in any individual because, to mature, thymocytes must react with low affinity but not high affinity with thymus expressed major histocompatibility (MHC)/peptides. MHC proteins are very polymorphic. Different alleles bind different peptides. Therefore, any individual might express many different MHC alleles to ensure that some peptides from an invader are bound to MHC and activate T cells. However, most individuals express limited numbers of MHC alleles. To explore this, we compared the TCR repertoires of naïve CD4 T cells in mice expressing one or two MHC alleles. Unexpectedly, the TCRs in heterozygotes were less diverse that those in the sum of their MHC homozygous relatives. Our results suggest that thymus negative selection cancels out the advantages of increased thymic positive selection in the MHC heterozygotes.

The Effects of Unitizing Nail-Plate Constructs in Distal Femur Fractures: A Biomechanical Study.

OBJECTIVES: To assess the biomechanical differences between linked and unlinked constructs in young and osteoporotic cadavers in addition to osteoporotic sawbones. METHODS: Intraarticular distal femur fractures with comminuted metaphyseal regions were created in three young matched pair cadavers, three osteoporotic matched pair cadavers, and six osteoporotic sawbones. Precontoured distal femur locking plates were placed in addition to a standardized retrograde nail, with unitized constructs having one 4.5 mm locking screw placed distally through the nail. Nonunitized constructs had seven 4.5 mm locking screws placed through the plate around the nail, with one 5 mm distal interlock placed through the nail alone. Cadaveric specimens were subjected to axial fatigue loads between 150 and 1500 N (R Ratio = 10) with 1 Hx frequency for 10,000 cycles. Sawbones were axially loaded at 50% of the ultimate load for fatigue testing to achieve runout, with testing performed with 30 and 300 N (R Ratio = 10) loads with 1 Hz frequency for 10,000 cycles. RESULTS: In young cadavers, there was no difference in the mean cyclic displacement of the unitized constructs (1.51 ± 0.62mm) compared to the non-unitized constructs (1.34 ± 0.47mm) (Figure 4A), (p = 0.722). In osteoporotic cadavers, there was no difference in the mean cyclic displacement of the unitized constructs (2.46 ± 0.47mm) compared to the non-unitized constructs (2.91 ± 1.49mm) (p =0.639). There was statistically no significant difference in cyclic displacement between the unitized and non-unitized groups in osteoporotic sawbones(p = 0.181). CONCLUSIONS: Linked constructs did not demonstrate increased axial stiffness or decreased cyclical displacement in comparison to unlinked constructs in young cadaveric specimens, osteoporotic cadaveric specimens, or osteoporotic sawbones.

Impacts of Deicer Salt on Water Quality Performance of Stormwater Bioretention Systems with Varied Vegetation and Hydrology.

Sodium chloride (NaCl) deicers contaminate bioretention and influence effluent water quality, the effects of which are not yet fully understood. We tested this by constructing 48 mesocosms in a greenhouse, each having Panicum virgatum, Eutrochium purpureum, or no vegetation; having an internal water storage (IWS) zone or not; and being exposed to high or low NaCl doses in the late winters of 2022 and 2023. Synthetic stormwater was applied and effluent was monitored through May 2023 with an end-of-experiment analysis of soil and plant biomass for nitrogen, phosphorus, copper, zinc, and total suspended solids (TSS). Average effluent loads increased in spring, after NaCl application, for total phosphorus (+61%), copper (+61%), zinc (+88%), and TSS (+66%). These four analytes recovered by summer, with average annual percent removals >85%. Vegetation and IWS reduced annual phosphorus (by -33 and -70%, respectively) and copper (by -24 and -40%) loads, while higher NaCl concentrations increased annual phosphorus (+107%), copper (+22%), and TSS (+51%) loads. Nitrogen removal was not linked with NaCl but was dependent upon the presence of IWS or vegetation. Post-NaCl effluent spikes pose seasonal risks to aquatic ecosystems, emphasizing the need for active maintenance, redundant removal mechanisms, and minimized exposure to NaCl.

Fracture Lines and Patterns in Intra-articular Distal Femur Fractures.

INTRODUCTION: Distal femur fractures are complex injuries that often present with multiple fragments, posing notable challenges to fixation. This study aimed to (1) use preoperative CT scans to graphically display fracture lines in intra-articular distal femur fractures and (2) identify common fracture patterns in these injuries. METHODS: All skeletally mature patients that underwent surgical fixation of Orthopaedic Trauma Association type 33C distal femur fractures between 2012 and 2022 were identified across two level 1 trauma centers (n = 63). Preoperative axial, sagittal, and coronal computed tomography scans were obtained. Fracture lines in each plane were traced out and superimposed on standardized distal femur cross-sections, generating a fracture map for each plane. Injury and fracture characteristics were summarized and compared between fracture patterns. RESULTS: On axial scans, 59 of 63 fractures contained a central intercondylar split from the intercondylar notch to the trochlea. On coronal scans, fracture lines originated at the notch and exited laterally and medially in the supracondylar region, creating a Y-shape. One-third of all fractures contained coronal fracture lines, with most involving the lateral condyle. Based on fracture line orientation and location, fractures were divided into four main fracture pattern types. Type 4 fractures (central split and medial coronal fracture line) were associated with lower average medial fracture height and a lower rate of medial metaphyseal comminution. DISCUSSION: We found that C-type distal femur fractures can present with four main fracture patterns. Most fractures contain a central sagittal intercondylar split, and a high proportion of fractures contain either medial or lateral coronal fracture lines. Fracture pattern was associated with mechanism of injury, presence of medial comminution, and medial fracture line height. Future studies should focus on clinical outcomes and surgical management of these distinct fracture patterns. LEVEL OF EVIDENCE: IV.

Chitosan-fulvic acid nanoparticles enhance drought tolerance in maize via antioxidant defense and transcriptional reprogramming.

Nanoparticles are promising alternatives to synthetic fertilizers in the context of climate change and sustainable agriculture. Maize plants were grown under gradient concentrations (50 µM, 100 µM, 200 µM, 500 µM, and 1 mM) of chitosan (Ch), fulvic acid (FA) or chitosan-fulvic acid nanoparticles (Ch-FANPs). Based on the overall phenotypic assessment, 100 µM was selected for downstream experiments. Maize plants grown under this optimized concentration were thereafter subjected to drought stress by water withholding for 14 days. Compared to the individual performances, the combined treatment of Ch-FANPs supported the best plant growth over chitosan, fulvic acid, or sole watered plants and alleviated the adverse effects of drought by enhancing root and shoot growth, and biomass by an average 20%. In addition, Ch-FANPs-treated plants exhibited a significant reduction in hydrogen peroxide (H2O2) content (~10%), with a concomitant increase in ascorbate peroxidase (APX) activity (>100%) while showing a reduced lipid peroxidation level observed by the decrease in malondialdehyde (MDA) content (~100%) and low electrolyte leakage level. Furthermore, chlorophyll content increased significantly (>100%) in maize plants treated with Ch-FANPs compared to Ch or FA and control in response to drought. The expression of drought-induced transcription factors, ZmDREB1A, ZmbZIP1, and ZmNAC28, and the ABA-dependent ZmCIPK3 was upregulated by Ch-FANPs. Owing to the above, Ch-FANPs are proposed as a growth-promoting agent and elicitor of drought tolerance in maize via activation of antioxidant machinery and transcriptional reprogramming of drought-related genes.

Dapagliflozin, inflammation and left ventricular remodelling in patients with type 2 diabetes and left ventricular hypertrophy.

BACKGROUND AND AIMS: Sodium-glucose co-transporter 2 (SGLT2) inhibitors have beneficial effects in heart failure (HF), including reverse remodelling, but the mechanisms by which these benefits are conferred are unclear. Inflammation is implicated in the pathophysiology of heart failure (HF) and there are some pre-clinical data suggesting that SGLT2 inhibitors may reduce inflammation. There is however a lack of clinical data. The aim of our study was to investigate whether improvements in cardiac remodelling caused by dapagliflozin in individuals with type 2 diabetes (T2D) and left ventricular hypertrophy (LVH) were associated with its effects on inflammation. METHODS: We measured C-reactive protein (CRP), tumor necrosis factor alpha (TNF-α), interleukin-1ß (IL-1ß), interleukin 6 (IL-6), and interleukin 10 (IL-10) and neutrophil-to-lymphocyte ratio (NLR) in plasma samples of 60 patients with T2D and left ventricular hypertrophy (LVH) but without symptomatic HF from the DAPA-LVH trial in which participants were randomised dapagliflozin 10 mg daily or placebo for 12 months and underwent cardiac magnetic resonance imaging (CMR) at baseline and end of treatment. The primary analysis was to investigate the effect of dapagliflozin on inflammation and to assess the relationships between changes in inflammatory markers and LV mass and global longitudinal strain (GLS) and whether the effect of dapagliflozin on LV mass and GLS was modulated by baseline levels of inflammation. RESULTS: Following 12 months of treatment dapagliflozin significantly reduced CRP compared to placebo (mean difference of -1.96; 95% CI -3.68 to -0.24, p = 0.026). There were no significant statistical changes in other inflammatory markers. There were modest correlations between improvements in GLS and reduced inflammation (NLR (r = 0.311), IL-1ß (r = 0.246), TNF-α (r = 0.230)) at 12 months. CONCLUSIONS: Dapagliflozin caused a significant reduction in CRP compared to placebo. There were correlations between reductions in inflammatory markers including IL-1ß and improvements in global longitudinal strain (but not reduced LV mass). Reductions in systemic inflammation might play a contributory role in the cardiovascular benefits of dapagliflozin. TRIAL REGISTRATION: Clinicaltrials.gov NCT02956811 (06/11/2016).

Mesocorticolimbic system reactivity to alcohol use-related visual cues as a function of alcohol sensitivity phenotype: A pilot fMRI study.

Low sensitivity (LS) to alcohol is a risk factor for alcohol use disorder (AUD). Compared to peers with high sensitivity (HS), LS individuals drink more, report more problems, and exhibit potentiated alcohol cue reactivity (ACR). Heightened ACR suggests LS confers AUD risk via incentive sensitization, which is thought to take place in the mesocorticolimbic system. This study examined neural ACR in LS and HS individuals. Young adults (N = 32, M age=20.3) were recruited based on the Alcohol Sensitivity Questionnaire (HS: n = 16; LS: n = 16; 9 females/group). Participants completed an event-related fMRI ACR task. Group LS had higher ACR in left ventrolateral prefrontal cortex than group HS. In group LS, ACR in left caudomedial orbitofrontal cortex or left putamen was low at low alcohol use levels and high at heavier or more problematic alcohol use levels, whereas the opposite was true in group HS. Alcohol use level also was associated with the level of ACR in left substantia nigra among males in group LS. Taken together, results suggest elevated mesocorticolimbic ACR among LS individuals, especially those using alcohol at hazardous levels. Future studies with larger samples are warranted to determine the neurobiological loci underlying LS-based amplified ACR and AUD risk.

Does obesity and varying body mass index affect the clinical outcomes and safety of biportal endoscopic lumbar decompression? A comparative cohort study.

BACKGROUND: Endoscopic spine surgery has recently grown in popularity due to the potential benefits of reduced pain and faster recovery time as compared to open surgery. Biportal spinal endoscopy has been successfully applied to lumbar disc herniations and lumbar spinal stenosis. Obesity is associated with increased risk of complications in spine surgery. Few prior studies have investigated the impact of obesity and associated medical comorbidities with biportal spinal endoscopy. METHODS: This study was a prospectively collected, retrospectively analyzed comparative cohort design. Patients were divided into cohorts of normal body weight (Bone Mass Index (BMI)18.0-24.9), overweight (BMI 25.0-29.9) and obese (BMI > 30.0) as defined by the World Health Organization (WHO). Patients underwent biportal spinal endoscopy by a single surgeon at a single institution for treatment of lumbar disc herniations and lumbar spinal stenosis. Demographic data, surgical complications, and patient-reported outcomes were analyzed. Statistics were calculated amongst treatment groups using analysis of variance and chi square where appropriate. Statistical significance was determined as p < 0.05. RESULTS: Eighty-four patients were followed. 26 (30.1%) were normal BMI, 35 (41.7%) were overweight and 23 (27.4%) were obese. Patients with increasing BMI had correspondingly greater American Society of Anesthesiologist (ASA) scores. There were no significant differences in VAS Back, VAS Leg, and ODI scores, or postoperative complications among the cohorts. There were no cases of surgical site infections in the cohort. All cohorts demonstrated significant improvement up to 1 year postoperatively. CONCLUSIONS: This study demonstrates that obesity is not a risk factor for increased perioperative complications with biportal spinal endoscopy and has similar clinical outcomes and safety profile as compared to patients with normal BMI. Biportal spinal endoscopy is a promising alternative to traditional techniques to treat common lumbar pathology.

Evaluating a Novel AI Tool for Automated Measurement of the Aortic Root and Valve in Cardiac Magnetic Resonance Imaging.

Objective Evaluating an artificial intelligence (AI) tool (AIATELLA, version 1.0; AIATELLA Oy, Helsinki, Finland) in interpreting cardiac magnetic resonance (CMR) imaging to produce measurements of the aortic root and valve by comparison of accuracy and efficiency with that of three National Health Service (NHS) cardiologists. Methods AI-derived aortic root and valve measurements were recorded alongside manual measurements from three experienced NHS consultant cardiologists (CCs) over three separate sites in the northeast part of the United Kingdom. The study utilised a comprehensive dataset of CMR images, with the intraclass correlation coefficient (ICC) being the primary measure of concordance between the AI and the cardiologist assessments. Patient imaging was anonymised and blinded at the point of transfer to a secure data server.  Results The study demonstrates a high level of concordance between AI assessment of the aortic root and valve with NHS cardiologists (ICC of 0.98). Notably, the AI delivered results in 2.6 seconds (+/- 0.532) compared to a mean of 334.5 seconds (+/- 61.9) by the cardiologists, a statistically significant improvement in efficiency without compromising accuracy. Conclusion AI's accuracy and speed of analysis suggest that it could be a valuable tool in cardiac diagnostics, addressing the challenges of time-consuming and variable clinician-based assessments. This research reinforces AI's role in optimising the patient journey and improving the efficiency of the diagnostic pathway.

Storylines of family medicine IX: people and places-diverse populations and locations of care.

Storylines of Family Medicine is a 12-part series of thematically linked mini-essays with accompanying illustrations that explore the many dimensions of family medicine as interpreted by individual family physicians and medical educators in the USA and elsewhere around the world. In 'IX: people and places-diverse populations and locations of care', authors address the following themes: 'LGBTQIA+health in family medicine', 'A family medicine approach to substance use disorders', 'Shameless medicine for people experiencing homelessness', '''Difficult" encounters-finding the person behind the patient', 'Attending to patients with medically unexplained symptoms', 'Making house calls and home visits', 'Family physicians in the procedure room', 'Robust rural family medicine' and 'Full-spectrum family medicine'. May readers appreciate the breadth of family medicine in these essays.

Does the use of tranexamic acid intraoperatively reduce postoperative blood loss and complications following biportal endoscopic lumbosacral decompression?

Background: Biportal endoscopic spine surgery is an effective minimally invasive technique for treating common lumbar pathologies. We aim to evaluate the impact of intraoperative tranexamic acid (TXA) use on postoperative blood loss in biportal endoscopic decompression surgery. Methods: Patients undergoing biportal endoscopic lumbar discectomies and decompressions either by same day surgery or overnight stay at a single institution beginning in October 2021 were prospectively enrolled. This study was non-randomized, non-blinded with the first cohort of consecutive patients receiving 1 g of intravenous TXA intra-operatively before closure and the second cohort of consecutive patients receiving no TXA. Exclusion criteria included any revision surgery, any surgery for the diagnosis of spinal instability, infection, tumor, or trauma, any contraindication for TXA. Results: Eighty-four patients were included in the study, with 45 (54%) receiving TXA and 39 (46%) not receiving TXA. Median follow-up was 168 days [interquartile range (IQR), 85-368 days]. There were no differences in patient or surgical characteristics between cohorts. Estimated blood loss (EBL) was similar (P=0.20), while post-operative drain output was significantly lower in the TXA cohort (P=0.0028). Single level discectomies had significantly less drain output as compared to 2 level unilateral laminotomy, bilateral decompression (ULBD) cases (P<0.005). Post-operative complications were similar, with low rates of wound complication (1.2%) and transient postoperative weakness (2.4%, P>0.99 for both). Oswestry disability index (ODI), visual analog scale (VAS) back and VAS leg scores decreased significantly; the absolute decrease in scores did not differ between groups (P=0.71, 0.22, 0.86, respectively). Conclusions: Systemic intraoperative TXA administration is associated with a significant decrease in post-operative blood loss in biportal spinal endoscopy, with no impact on the improvement in patient-reported outcomes (PROs) or rate of post-operative complications. Single level biportal discectomies had significantly less postoperative drainage with TXA and may not need drains postoperatively. Larger, randomized studies are necessary to evaluate the cost-effectiveness of TXA use in biportal spinal endoscopy.

Similar Medium-Term Revision Rates Following Acute Total Hip Arthroplasty Versus Open Reduction and Internal Fixation for Acetabular Fractures in the Elderly.

BACKGROUND: The management of elderly acetabular fractures is complex, with high rates of conversion total hip arthroplasty (THA) after open reduction and internal fixation (ORIF), but potentially higher rates of complications after acute THA. METHODS: The California Office of Statewide Health Planning and Development database was queried between 2010 and 2017 for all patients aged 60 years or older who sustained a closed, isolated acetabular fracture and underwent ORIF, THA, or a combination. Chi-square tests and Student t tests were used to identify demographic differences between groups. Multivariate regression was used to evaluate predictors of 30-day readmission and 90-day complications. Kaplan-Meier (KM) survival analysis and Cox proportional hazards model were used to estimate the revision surgery-free survival (revision-free survival [RFS]), with revision surgery defined as conversion THA, revision ORIF, or revision THA. RESULTS: A total of 2,184 surgically managed acetabular fractures in elderly patients were identified, with 1,637 (75.0%) undergoing ORIF and 547 (25.0%) undergoing THA with or without ORIF. Median follow-up was 295 days (interquartile range, 13 to 1720 days). 99.4% of revisions following ORIF were for conversion arthroplasty. Unadjusted KM analysis showed no difference in RFS between ORIF and THA (log-rank test P = 0.27). RFS for ORIF patients was 95.1%, 85.8%, 78.3%, and 71.4% at 6, 12, 24 and 60 months, respectively. RFS for THA patients was 91.6%, 88.9%, 87.2%, and 78.8% at 6, 12, 24 and 60 months, respectively. Roughly 50% of revisions occurred within the first year postoperatively (49% for ORIF, 52% for THA). In propensity score-matched analysis, there was no difference between RFS on KM analysis ( P = 0.22). CONCLUSIONS: No difference was observed in medium-term RFS between acute THA and ORIF for elderly acetabular fractures in California. Revision surgeries for either conversion or revision THA were relatively common in both groups, with roughly half of all revisions occurring within the first year postoperatively. LEVEL OF EVIDENCE: III.

Compliant Intramedullary Stems for Joint Reconstruction.

The longevity of current joint replacements is limited by aseptic loosening, which is the primary cause of non-infectious failure for hip, knee, and ankle arthroplasty. Aseptic loosening is typically caused either by osteolysis from particulate wear, or by high shear stresses at the bone-implant interface from over-constraint. Our objective was to demonstrate feasibility of a compliant intramedullary stem that eliminates over-constraint without generating particulate wear. The compliant stem is built around a compliant mechanism that permits rotation about a single axis. We first established several models to understand the relationship between mechanism geometry and implant performance under a given angular displacement and compressive load. We then used a neural network to identify a design space of geometries that would support an expected 100-year fatigue life inside the body. We additively manufactured one representative mechanism for each of three anatomic locations, and evaluated these prototypes on a KR-210 robot. The neural network predicts maximum stress and torsional stiffness with 2.69% and 4.08% error respectively, relative to finite element analysis data. We identified feasible design spaces for all three of the anatomic locations. Simulated peak stresses for the three stem prototypes were below the fatigue limit. Benchtop performance of all three prototypes was within design specifications. Our results demonstrate the feasibility of designing patient- and joint-specific compliant stems that address the root causes of aseptic loosening. Guided by these results, we expect the use of compliant intramedullary stems in joint reconstruction technology to increase implant lifetime.

Postoperative Care and Outcomes in Solid-Organ Transplant Patients Undergoing Lower Extremity Fracture Treatment.

OBJECTIVES: To determine the postoperative outcomes in solid-organ transplant (SOT) patients undergoing operative treatment of lower extremity fractures. DESIGN: Retrospective comparative study. SETTING: Academic Level 1 trauma center. PATIENT SELECTION CRITERIA: Patients who underwent SOT and operative treatment of lower extremity fracture from 2013 to 2021 were identified, excluding pathologic fractures. OUTCOME MEASURES AND COMPARISONS: Postoperative complications, length of stay, time to death, 90-day and 1-year readmission rates, readmission causes, discharge location, and immunosuppressive regiments. RESULTS: Sixty-one patients with an average age of 67 years (range 29-88) were included. The mortality rate was 37.7%. The average follow-up was 15.2 months (range of 2 weeks-10 years). The majority of patients (32.8%) had received a liver transplant, and femoral neck fractures constituted the largest fracture group. The average length of stay was 10 days, with the shortest being 1 day and the longest being 126 days (SD 18). The majority of patients (57.3%) were not discharged home. Only 2 suffered from a postoperative complication requiring another procedure: hardware removal and liner exchange for periprosthetic joint infection, respectively. There was a 27.9% 90-day readmission rate with 2 deaths within that period with the most common being altered mental status (29.4%), genitourinary infections (17.6%), repeat falls (11.8%), and low hemoglobin requiring transfusion (11.8%). The longest average time to death analyzed by transplant type was found among lung transplant patients (1076 days, 62.5% mortality), followed by liver transplant patients (949 days, 35.0% mortality), and then kidney transplant patients (834 days, 38.9% mortality). The shortest time to death was 71 days from index procedure. CONCLUSIONS: Family members of SOT patients undergoing operative treatment of lower extremity fractures should be made aware of the high risk for 90-day readmission postoperatively (27.9%) and overall mortality (12.5%). Providers should be aware of the need for multidisciplinary involvement for inpatient care, monitoring postoperative complications, and facilitating discharge planning. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

An Open One-Step RT-qPCR for SARS-CoV-2 detection.

The COVID-19 pandemic has resulted in millions of deaths globally, and while several diagnostic systems were proposed, real-time reverse transcription polymerase chain reaction (RT-PCR) remains the gold standard. However, diagnostic reagents, including enzymes used in RT-PCR, are subject to centralized production models and intellectual property restrictions, which present a challenge for less developed countries. With the aim of generating a standardized One-Step open RT-qPCR protocol to detect SARS-CoV-2 RNA in clinical samples, we purified and tested recombinant enzymes and a non-proprietary buffer. The protocol utilized M-MLV RT and Taq DNA pol enzymes to perform a Taqman probe-based assay. Synthetic RNA samples were used to validate the One-Step RT-qPCR components, demonstrating sensitivity comparable to a commercial kit routinely employed in clinical settings for patient diagnosis. Further evaluation on 40 clinical samples (20 positive and 20 negative) confirmed its comparable diagnostic accuracy. This study represents a proof of concept for an open approach to developing diagnostic kits for viral infections and diseases, which could provide a cost-effective and accessible solution for less developed countries.

MELD score predicts short-term outcomes after surgical management of proximal humerus fractures: a matched analysis.

Objective: We aimed to evaluate the difference in 30-day outcomes after surgical management of proximal humerus fractures (PHFs) between patients with and without chronic liver disease as defined by a MELD score greater than 10. Design: This was a retrospective database review. Setting: All centers participating in the American College of Surgeons National Surgical Quality Improvement Program database were included. Patients/Participants: Patients with proximal humerus fractures who (1) underwent ORIF, HA, or SA and (2) had calculable MELD scores were included. Intervention: Open reduction and internal fixation, hemiarthroplasty, or shoulder arthroplasty was used for treatment. Main outcome measurements: Thirty-day complications, mortality, readmission, and reoperation rates were measured. Results: Of the total 1732 PHF patients identified, 300 had a MELD score higher than 10. After propensity matching by significant covariates, MELD score higher than 10 was found to be significantly associated with higher rates of 30-day mortality, 30-day readmission, transfusion within 72 hours, and systemic complications. Among patients with a MELD score higher than 10, treatment with SA or HA instead of ORIF was associated with a higher rate of transfusion and longer operative time. There were no significant differences between treatment cohorts regarding mortality, reoperation, readmission, or complications. Conclusions: A MELD score higher than 10 is associated with higher risk of surgical complications, transfusion, and death in patients undergoing surgery for proximal humerus fractures. Among patients with a MELD score higher than 10, ORIF was associated with a lower transfusion rate and shorter operative time than arthroplasty or hemiarthroplasty. Level of Evidence: Prognostic Level III.

Biportal Endoscopic Approach for Lumbar Degenerative Disease in the Ambulatory Outpatient vs Inpatient Setting: A Comparative Study.

BACKGROUND: Biportal spinal endoscopy is increasingly utilized for lumbar disc herniations and lumbar stenosis. The objective was to investigate the safety and effectiveness of the technique in the outpatient vs inpatient setting. METHODS: This is a comparative study of consecutive patients who underwent biportal spinal endoscopy by a single surgeon at a single institution. Demographics, surgical complications, and patient-reported outcomes were prospectively collected and retrospectively analyzed. Statistics were calculated among treatment groups using unpaired t test and χ 2 analysis where appropriate. Statistical significance was determined as P < 0.05. RESULTS: Eighty-four patients were included, 58 (69.0%) as outpatient, 26 (31.0%) as inpatient. Mean follow-up was 7.5 months. Statistically significant differences in age, American Society of Anesthesiologists classification, and Charleston Comorbidity Index scores were reported between cohorts, with younger and healthier patients undergoing outpatient surgery (P < 0.0001). Outpatients were more likely to have discectomies while inpatients were more likely to have decompressions for stenosis. No significant differences in postoperative complications were found between groups.Both cohorts demonstrated significant improvement in visual analog scale (VAS) back and leg pain scores and Oswestry Disability Index scores (P < 0.001). Outpatients had significantly lower postoperative VAS back pain (P = 0.001) and Oswestry Disability Index scores (P = 0.004) at 5-8 weeks compared with inpatients, but there was no significant difference for VAS leg pain scores at all time points between the cohorts. CONCLUSIONS: Early results demonstrate that biportal spinal endoscopy can safely and effectively be performed in both inpatient and outpatient settings. CLINICAL RELEVANCE: Outpatient biportal spinal endoscopy can be performed successfully in well selected patients, which may reduce the financial burden of spine surgery to the U.S. healthcare system.

Organoid co-culture model of the human endometrium in a fully synthetic extracellular matrix enables the study of epithelial-stromal crosstalk.

BACKGROUND: The human endometrium undergoes recurring cycles of growth, differentiation, and breakdown in response to sex hormones. Dysregulation of epithelial-stromal communication during hormone-mediated signaling may be linked to myriad gynecological disorders for which treatments remain inadequate. Here, we describe a completely defined, synthetic extracellular matrix that enables co-culture of human endometrial epithelial and stromal cells in a manner that captures healthy and disease states across a simulated menstrual cycle. METHODS: We parsed cycle-dependent endometrial integrin expression and matrix composition to define candidate cell-matrix interaction cues for inclusion in a polyethylene glycol (PEG)-based hydrogel crosslinked with matrix metalloproteinase-labile peptides. We semi-empirically screened a parameter space of biophysical and molecular features representative of the endometrium to define compositions suitable for hormone-driven expansion and differentiation of epithelial organoids, stromal cells, and co-cultures of the two cell types. FINDINGS: Each cell type exhibited characteristic morphological and molecular responses to hormone changes when co-encapsulated in hydrogels tuned to a stiffness regime similar to the native tissue and functionalized with a collagen-derived adhesion peptide (GFOGER) and a fibronectin-derived peptide (PHSRN-K-RGD). Analysis of cell-cell crosstalk during interleukin 1B (IL1B)-induced inflammation revealed dysregulation of epithelial proliferation mediated by stromal cells. CONCLUSIONS: Altogether, we demonstrate the development of a fully synthetic matrix to sustain the dynamic changes of the endometrial microenvironment and support its applications to understand menstrual health and endometriotic diseases. FUNDING: This work was supported by The John and Karine Begg Foundation, the Manton Foundation, and NIH U01 (EB029132).