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Background Complications after open reduction internal fixation (ORIF) for distal radius fractures (DRFs) are well documented, but the impact of trainee involvement on postoperative outcomes has not been studied.Questions Does trainee involvement affect postoperative complication rates and length of hospital stay?Methods The American College of Surgeons National Surgical Quality Improvement Program was queried from 2006 to 2012 for patients undergoing DRF ORIF. A 1:1 propensity score-matched resident/fellow involved cases to attending-only cases. Demographics, length of stay, and postoperative complications were compared between the two groups. Logistic regression was used to evaluate independent predictors of adverse events and to evaluate cases with and without trainee involvement.Results Overall, 3,003 patients underwent DRF ORIF from 2006 to 2012. After matching, 1,150 cases (50% with resident/fellow involvement) were included. The overall rate of adverse events was 4.4% (46/1,050). There were no significant differences in the short-term complication rate in trainee-involved (2.3%) versus attending-only cases (3.9%) (p = 0.461). For ORIF of DRF, there were no significant differences, between attending-only cases and resident/fellow-involved cases, with regards to short-term major complications (p = 0.720) or minor complications (p = 0.374). Length of hospital stay was similar between cohorts (1.22 vs. 0.98 days) (p = 0.723). On multivariate analysis, trainee involvement was not an independent predictor of minor, major, or any complication after DRF fixation after controlling for multiple independent factors (all p > 0.364).Discussion Trainee participation in DRF ORIF is not associated with increased risk for short-term (30-day) medical or surgical postoperative complications.Level of Evidence IV case–control study.

Introduction The effects of preoperative dehydration on outcomes following total ankle arthroplasty (TAA) remain unknown. Therefore, the purpose of this study is to evaluate the association between dehydration and postoperative complications for patients undergoing TAA. Methods Patients undergoing TAA from 2007 to 2019 were identified in the National Surgical Quality Improvement Program (NSQIP) database. A preoperative serum blood urea nitrogen/creatinine (BUN/Cr) greater than 20 was used to define preoperative dehydration. Patients were stratified into 2 cohorts: patients who were dehydrated (BUN/Cr > 20) and patients without dehydration (BUN/Cr ≤ 20). In this analysis, various postoperative outcomes were assessed with bivariate and multivariate analyses. Results In total, 1033 patients underwent TAA and had their serum BUN and Cr values recorded. For both BUN and Cr, the patients in this study had their serum values recorded a mean of 15 days before their surgery. A total of 588 patients (56.9%) did not have dehydration preoperatively and 445 patients (43.1%) were dehydrated. Following adjustment on multivariate analysis, an increased risk of extended length of hospital stay (odds ratio [OR] = 1.457; p = 0.024) was seen in the dehydrated group compared with those who were noted to be well hydrated. Conclusion As fluid intake is one modifiable preoperative variable that can be easily monitored during elective procedures, it is important for physicians to be aware of patients who are dehydrated and adjust their fluids appropriately to optimize postoperative outcomes. Levels of Evidence: Level III: Retrospective cohort study

Total shoulder arthroplasty (TSA) is one of the fastest growing procedures in terms of volume performed in hospitals in the United States. In 2020, elective surgery was suspended nationwide as a result of the SARS-CoV-2 (COVID-19) pandemic, and the use trends in the wake of the pandemic have yet to be evaluated substantially. Nationwide case volume reduction for TSA is unknown; therefore, the aim of this study is to compare patient demographics, complications, and temporal trends in case volume of elective TSA in the calendar year 2019 (prepandemic) to 2020 in the United States.Using a multicenter, nationwide representative sample from 2019 to 2020, a retrospective query was conducted for all patients undergoing elective TSA. Patients undergoing surgery pre-COVID (2019 and 2020 Q1) were compared to those during COVID (2020 Q2-Q4). Temporal trends in case volumes were compared between time frames. TSA use, patient demographics, complications, and length of stay were compared between years. Linear regression was used to evaluate for changes in the case volume over the study period. A statistical significance threshold of P .05 was used.In total, 9667 patients underwent elective TSA in 2019 (n = 5342) and 2020 (n = 4325). The proportion of patients who underwent outpatient TSA in 2020 was significantly greater than the year prior (20.6% vs. 13.9%; P .001). Overall, elective TSA case volume declined by 19.0% from 2019 to 2020. There was no significant difference in the volume of cases in 2019 Q1 (n = 1401) through 2020 Q1 (n = 1296) (P = .216). However, elective TSA volumes declined by 54.6% in 2020 Q2. Elective TSA case volumes recovered to prepandemic baseline in 2020 Q3 and 2020 Q4. The average length of stay was comparable in 2020 vs. 2019 (1.29 vs. 1.32 days; P = .371), with the proportion of same-day discharge increasing per quarter from 2019 to 2020 (from 11.8% to 26.8% of annual cases). There was no significant difference in the total complication rates in 2019 (4.6%) vs. 2020 (4.9%) (P = .441).Using a nationwide sample, elective TSA precipitously declined during the second quarter of 2020. Patient demographics of those undergoing elective TSA in 2020 were similar in comorbidity burden. A large proportion of surgeries were transitioned to the outpatient setting, with rates of same-day discharge doubling over the study period despite no change in overall complication rates.

Post-transplant diarrhea is a common complication after solid organ transplantation and is frequently attributed to the widely prescribed immunosuppressant mycophenolate mofetil (MMF). Given recent work identifying the relationship between MMF toxicity and gut bacterial β-glucuronidase activity, we evaluated the relationship between gut microbiota composition, fecal β-glucuronidase activity, and post-transplant diarrhea. We recruited 97 kidney transplant recipients and profiled the gut microbiota in 273 fecal specimens using 16S rRNA gene sequencing. We further characterized fecal β-glucuronidase activity in a subset of this cohort. Kidney transplant recipients with post-transplant diarrhea had decreased gut microbial diversity and decreased relative gut abundances of 12 genera when compared to those without post-transplant diarrhea (adjusted p value < .15, Wilcoxon rank sum test). Among the kidney transplant recipients with post-transplant diarrhea, those with higher fecal β-glucuronidase activity had a more prolonged course of diarrhea (≥7 days) compared to patients with lower fecal β-glucuronidase activity (91% vs 40%, p = .02, Fisher's exact test). Our data reveal post-transplant diarrhea as a complex phenomenon with decreased gut microbial diversity and commensal gut organisms. This study further links commensal bacterial metabolism with an important clinical outcome measure, suggesting fecal β-glucuronidase activity could be a novel biomarker for gastrointestinal-related MMF toxicity.

Background: Antiplatelet therapies are often withheld before and after platelet-rich plasma product (PRPP) administration due to theoretical concerns that therapies that inhibit the function of platelets would inhibit the effects of PRPP. Purpose/Hypothesis: The purpose of this study was to evaluate the effect that antiplatelet therapies have on the ability of PRPP to stimulate wound healing and tissue regeneration. Our hypothesis was that antiplatelet therapies would have highly heterogeneous effects on the biological activity of PRPP. Study Design: Narrative review. Methods: The Medline database was searched via PubMed to identify all studies related to PRPP and antiplatelet therapies, yielding 1417 publications. After the search was confined to articles published after 1995, there were 901 articles remaining. All abstracts were then screened to identify animal or human clinical studies that focused on growth factor or inflammatory cytokine production or treatment outcomes. We limited our analysis to studies reporting on orthopaedic pathologies and in vitro studies of antiplatelet therapies. Ultimately, 12 articles fit the search criteria. Results: The majority of studies reported on the use of nonsteroidal anti-inflammatory drugs as antiplatelet therapy. The majority of studies were in vitro analyses of growth factors, inflammatory cytokines, or cell viability, whereas 1 study examined clinical outcomes in an animal model. None of the studies investigated clinical outcomes in humans. All of the studies showed no effect or mixed effects of antiplatelet therapies on PRPP efficacy. One study showed PRPP recovery to baseline function after a 1-week washout period. Conclusion: The literature did not provide support for the common clinical practice of withholding antiplatelet therapies in patients being treated with PRPP.

Urinary tract infection (UTI) is a common complication in kidney transplant recipients and can lead to significant morbidity and mortality. Recent evidence supports a role for the gut as a source for UTIs but little is known about the relationship between gut commensal bacteria and UTI development. We hypothesized that the abundance of gut commensal bacteria is associated with a lower risk of developing bacteriuria and UTIs. We performed gut microbiome profiling using 16S rRNA gene sequencing of the V4-V5 hypervariable region on 510 fecal specimens in 168 kidney transplant recipients. Fifty-one kidney transplant recipients (30%) developed Enterobacteriaceae bacteriuria within the first 6 months after transplantation (Enterobacteriaceae Bacteriuria Group) and 117 did not (No Enterobacteriaceae Bacteriuria Group). The relative abundances of Faecalibacterium and Romboutsia were significantly higher in the fecal specimens from the No Enterobacteriaceae Bacteriuria Group than those from the Enterobacteriaceae Bacteriuria Group (Adjusted P value

Posttransplant diarrhea is associated with kidney allograft failure and death, but its etiology remains unknown in the majority of cases. Because altered gut microbial ecology is a potential basis for diarrhea, we investigated whether posttransplant diarrhea is associated with gut dysbiosis. We enrolled 71 kidney allograft recipients for serial fecal specimen collections in the first 3 months of transplantation and profiled the gut microbiota using 16S ribosomal RNA (rRNA) gene V4-V5 deep sequencing. The Shannon diversity index was significantly lower in 28 diarrheal fecal specimens from 25 recipients with posttransplant diarrhea than in 112 fecal specimens from 46 recipients without posttransplant diarrhea. We found a lower relative abundance of 13 commensal genera (Benjamini-Hochberg adjusted P ≤ .15) in the diarrheal fecal specimens including the same 4 genera identified in our prior study. The 28 diarrheal fecal specimens were also evaluated by a multiplexed polymerase chain reaction (PCR) assay for 22 bacterial, viral, and protozoan gastrointestinal pathogens, and 26 specimens were negative for infectious etiologies. Using PICRUSt (Phylogenetic Investigation of Communities by Reconstruction of Unobserved States) to predict metagenomic functions, we found that diarrheal fecal specimens had a lower abundance of metabolic genes. Our findings suggest that posttransplant diarrhea is not associated with common infectious diarrheal pathogens but with a gut dysbiosis.

Background The gut microbiome is being associated increasingly with development of infections besides Clostridium difficile infection. A recent study found an association between butyrate‐producing gut (BPG) bacteria and less frequent development of lower respiratory viral infections in allogeneic hematopoietic stem cell transplant recipients (Haak et al, Blood 131(26): 2978, 2018). In this investigation, we examine the relationship between the abundance of BPG bacteria and the development of viral infections in a cohort of kidney transplant recipients. Methods We recruited 168 kidney transplant recipients who provided 510 fecal specimens in the first 3 months after transplantation and profiled the gut microbiota using 16S rRNA gene sequencing of the V4‐V5 hypervariable region. We classified the kidney transplant recipients into higher BPG Bacteria Group and lower BPG Bacteria Group using the same criteria of 1% relative gut abundance of BPG bacteria as the Haak et al study. Results Administration of antibiotics against anaerobes was associated with a significant decrease in the relative gut abundance of BPG bacteria. The higher BPG Bacteria Group was associated with less development of respiratory viral infections (Hazard Ratio [HR]: 0.28, P = .01) but not with less development of CMV viremia (HR: 0.38, P = .13) or BK viremia (HR: 1.02, P = .98) at 2 years post transplantation. Conclusion Our pilot investigation supports future validation of the relationship between high relative gut abundance of BPG bacteria and decreased risk for development of respiratory viral infections.

BACKGROUND. In kidney transplant recipients, gastrointestinal (GI) pathogens in feces are only evaluated during diarrheal episodes. Little is known about the prevalence of GI pathogens in asymptomatic individuals in this population. METHODS. We recruited 142 kidney transplant recipients who provided a non-diarrheal fecal sample within the first 10 days after transplantation. The specimens were evaluated for GI pathogens using the BioFire® FilmArray® GI Panel (BioFire® Diagnostics, LLC; Salt Lake City, UT), which tests for 22 pathogens. The fecal microbiome was also characterized using 16S rRNA gene sequencing of the V4-V5 hypervariable region. We evaluated whether detection of Clostridioides difficile and other GI pathogens was associated with post-transplant diarrhea within the first 3 months after transplantation. RESULTS. Among the 142 subjects, a potential pathogen was detected in 43 (30%) using the GI Panel. The most common organisms detected were C. difficile (n=24, 17%), enteropathogenic Escherichia coli (n=8, 6%), and norovirus (n=5, 4%). Detection of a pathogen on the GI panel or detection of C. difficile alone was not associated with future post-transplant diarrhea (P > 0.05). The estimated number of gut bacterial species was significantly lower in subjects colonized with C. difficile than those not colonized with a GI pathogen (P = 0.01) CONCLUSION. Colonization with GI pathogens, particularly C. difficile, is common at the time of kidney transplantation but does not predict subsequent diarrhea. Detection of C. difficile carriage was associated with decreased microbial diversity and may be a biomarker of gut dysbiosis.

High concentrations of polycyclic aromatic hydrocarbons (PAHs) in streams can be a significant stressor to aquatic organisms. To understand the likely sources and toxicity of PAHs in Milwaukee-area streams, streambed sediment samples from 40 sites and parking lot dust samples from 6 sites were analyzed for 38 parent PAHs and 25 alkylated PAHs. Diagnostic ratios, profile correlations, principal components analysis, source-receptor modeling, and mass fractions analysis were used to identify potential PAH sources to streambed sediment samples, and land-use analysis was used to relate streambed sediment PAH concentrations to different urban-related land uses. On the basis of this multiple lines-of-evidence approach, coal-tar pavement sealant was indicated as the primary source of PAHs in a majority of streambed sediment samples, contributing an estimated 77% of total PAHs to samples, on average. Comparison with the probable effect concentrations and (or) the equilibrium partitioning sediment benchmark indicates that 78% of stream sediment samples are likely to cause adverse effects to benthic organisms. Laboratory toxicity tests on a 16-sample subset of the streambed sites using the amphipod Hyalella azteca (28-d) and the midge Chironomus dilutus (10-d) measured significant reductions in 1 or more biological endpoints, including survival, in 75% of samples, with H. azteca more responsive than C. dilutus. Environ Toxicol Chem 2017;36:1622–1635. © 2016 The Authors. Environmental Toxicology and Chemistry Published by Wiley Periodicals, Inc. on behalf of SETAC.

Contamination of surface and drinking water due to the presence of Escherichia coli bacteria is a major cause of water-borne disease outbreak. To address unmet challenges for practical pathogen detection in contaminated samples, we report fabrication of thermally reduced graphene oxide-based field-effect transistor (rGO FET) passivated with an ultrathin layer of Al2O3 for real-time detection of E. coli bacteria. The sensor could detect a single E. coli cell within 50 s in a 1 µL sample volume. The ultrathin layer of Al2O3 acted as a barrier between rGO and potential interferents present in the sample. E. coli specific antibodies anchored on gold nanoparticles acted as probes for selective capture of E. coli. The high density of negative charge on the surface of E. coli cells strongly modulates the concentration of majority charge carriers in the rGO monolayer, thereby allowing real-time monitoring of E. coli concentration in a given sample. With a low detection limit of single cell, the FET sensor had a linear range of 1–100 CFU in 1 µL volume of sample (i.e., 103 to 105 CFU/ mL). The biosensor with good selectivity and rapid detection was further successfully demonstrated for E. coli sensing in river water. The rGO-based FET sensor provides a low cost and label-free approach, and can be mass produced for detection of a broad spectrum of pathogens in water or other liquid media.

Forest management techniques such as intermediate stand-tending practices (e.g., thinning) can promote climatic resiliency in forest stands by moderating tree competition. Residual trees gain increased access to environmental resources (i.e., soil moisture, light), which in turn has the potential to buffer trees from stressful climatic conditions. The influences of climate (temperature and precipitation) and forest management (thinning method and intensity) on the productivity of red pine (Pinus resinosa Ait.) in Michigan were examined to assess whether repeated thinning treatments were able to increase climatic resiliency (i.e., maintaining productivity and reduced sensitivity to climatic stress). The cumulative productivity of each thinning treatment was determined, and it was found that thinning from below to a residual basal area of 14 m2·ha−1 produced the largest average tree size but also the second lowest overall biomass per acre. On the other hand, the uncut control and the thinning from above to a residual basal area of 28 m2·ha−1 produced the smallest average tree size but also the greatest overall biomass per acre. Dendrochronological methods were used to quantify sensitivity of annual radial growth to monthly and seasonal climatic factors for each thinning treatment type. Climatic sensitivity was influenced by thinning method (i.e., thinning from below decreased sensitivity to climatic stress more than thinning from above) and by thinning intensity (i.e., more intense thinning led to a lower climatic sensitivity). Overall, thinning from below to a residual basal area of 21 m2·ha−1 represented a potentially beneficial compromise to maximize tree size, biomass per acre, and reduced sensitivity to climatic stress, and, thus, the highest level of climatic resilience.

We examined the effects of climate (i.e. temperature, precipitation, moisture index, river discharge) on the radial growth of eastern white pine (Pinus strobus) in two contrasting microhabitats (floodway versus terrace) in relation to an elevational and moisture gradient along the banks of the Red Cedar River, Michigan. We hypothesized that trees growing on the terrace sites would have a greater sensitivity to climatic factors than trees growing in the floodway. Increment cores were sampled and crossdated from dominant and co-dominant trees in the floodway and terrace sites and standardized growth chronologies were developed. Mean sensitivity, standard deviation, percentage of absent rings, and intertree correlation were generally greater for eastern white pine on the terrace compared to the floodway forests. Dendroclimatic relationships were examined with bootstrapped correlation analysis, which indicated that radial growth of eastern white pine in both floodway and terrace sites was negatively associated with summer temperature (i.e. June and July) of the current growing season. Radial growth in both floodway and terrace sites were positively related to current May precipitation, moisture index, and river discharge. Dendroclimatic response of eastern white pine in floodway and terrace sites differed in that the effect of summer moisture stress was more persistent in the terrace sites into later summer (i.e. current July ) whereas floodway sites showed a negative response to prior-year May precipitation and moisture index. Although precipitation and hydrological conditions of the river were generally favorable during the summer months, which appeared to have promoted soil moisture recharge, flooding in early winter (i.e. prior November) had a negative impact on growth in both microhabitats. The effect of winter river discharge was significantly negative in January (t) in the floodway sites compared to the terrace sites.

High concentrations of polycyclic aromatic hydrocarbons (PAHs) in streams can be a significant stressor to aquatic organisms. To understand the likely sources and toxicity of PAHs in Milwaukee-area streams, streambed sediment samples from 40 sites and parking lot dust samples from 6 sites were analyzed for 38 parent PAHs and 25 alkylated PAHs. Diagnostic ratios, profile correlations, principal components analysis, source-receptor modeling, and mass fractions analysis were used to identify potential PAH sources to streambed sediment samples, and land-use analysis was used to relate streambed sediment PAH concentrations to different urban-related land uses. On the basis of this multiple lines-of-evidence approach, coal-tar pavement sealant was indicated as the primary source of PAHs in a majority of streambed sediment samples, contributing an estimated 77% of total PAHs to samples, on average. Comparison with the probable effect concentrations and (or) the equilibrium partitioning sediment benchmark indicates that 78% of stream sediment samples are likely to cause adverse effects to benthic organisms. Laboratory toxicity tests on a 16-sample subset of the streambed sites using the amphipod Hyalella azteca (28-d) and the midge Chironomus dilutus (10-d) measured significant reductions in 1 or more biological endpoints, including survival, in 75% of samples, with H. azteca more responsive than C. dilutus. Environ Toxicol Chem 2017;36:1622-1635. © 2016 The Authors. Environmental Toxicology and Chemistry Published by Wiley Periodicals, Inc. on behalf of SETAC.

Changes in climate are predicted to significantly affect the productivity of trees in the Great Lakes region over the next century. Forest management decisions, such as initial stand density, can promote climatic resiliency and moderate decreased productivity through the reduction of tree competition. The influences of climate (temperature and precipitation) and forest management (initial stand density) on the productivity of red pine (Pinus resinosa) across multiple sites within Huron National Forest, Michigan, were examined using dendrochronological methods. Two common planting regimes were compared in this analysis; low initial density (1977 trees per hectare). Low initial density stands were found to have a higher climatic resilience by combining equal or greater measures of productivity, while having a reduced sensitivity to monthly and seasonal climate, particularly to summer drought.

Objective This study was conducted to stimulate respiratory muscles by functional magnetic stimulation (FMS) of the spinal nerves (T1-L5) to obtain maximum expiratory function. Design A prospective before and after trial. Setting Functional Magnetic Stimulation Laboratory, Spinal Cord Injury Service, VA Palo Alto Health Care System, Palo Alto, CA. Participants Twelve normal able-bodied subjects. Intervention A commercially available magnetic stimulator with a round magnetic coil (MC) was used. Respiratory muscle activation was achieved by placing the MC at each spinous process ranging from T1 to L5 vertebral levels. Main outcome measure The planned major outcome was to determine the optimal MC placement for producing maximal expiratory pressure (MEP) and expiratory reserve volume (ERV) by FMS. These measurements were compared with the subjects' voluntary maximal efforts. A profile with varying stimulation intensities was also obtained in select individuals for determining the highest expiratory pressure. Results Stimulation at the T9 spinal level resulted in the highest mean MEP and ERV. Stimulation between T8 and L5 produced similar MEP and ERV as obtained from the T9 MC placement. The mean maximum MEP and ERV produced by FMS were 76.8 +/- 6.4 cm H2O (7.52 +/- 0.62 kPa) and 1.28 +/- 0.15 L, which were 67% and 79% of the subjects' voluntary maximal efforts, respectively. A stimulation intensity of 80% resulted in the highest expiratory pressure. Conclusion FMS of lower thoracic and lumbar regions produced significant expiratory pressures and volumes. FMS of the expiratory muscles may prove to be a valuable technique for restoring cough in patients with spinal cord injury or other neurologic diseases, and in critical care or perioperative settings.