Assessing the Oxidative Potential of Outdoor PM2.5 in Wintertime Fairbanks, Alaska.

The oxidative potential (OP) of outdoor PM2.5 in wintertime Fairbanks, Alaska, is investigated and compared to those in wintertime Atlanta and Los Angeles. Approximately 40 filter samples collected in January-February 2022 at a Fairbanks residential site were analyzed for OP utilizing dithiothreitol-depletion (OPDTT) and hydroxyl-generation (OPOH) assays. The study-average PM2.5 mass concentration was 12.8 µg/m3, with a 1 h average maximum of 89.0 µg/m3. Regression analysis, correlations with source tracers, and contrast between cold and warmer events indicated that OPDTT was mainly sensitive to copper, elemental carbon, and organic aerosol from residential wood burning, and OPOH to iron and organic aerosol from vehicles. Despite low photochemically-driven oxidation rates, the water-soluble fraction of OPDTT was unusually high at 77%, mainly from wood burning emissions. In contrast to other locations, the Fairbanks average PM2.5 mass concentration was higher than Atlanta and Los Angeles, whereas OPDTT in Fairbanks and Atlanta were similar, and Los Angeles had the highest OPDTT and OPOH. Site differences were observed in OP when normalized by both the volume of air sampled and the particle mass concentration, corresponding to exposure and the intrinsic health-related properties of PM2.5, respectively. The sensitivity of OP assays to specific aerosol components and sources can provide insights beyond the PM2.5 mass concentration when assessing air quality.

Indoor-Outdoor Oxidative Potential of PM2.5 in Wintertime Fairbanks, Alaska: Impact of Air Infiltration and Indoor Activities.

The indoor air quality of a residential home during winter in Fairbanks, Alaska, was investigated and contrasted with outdoor levels. Twenty-four-hour average indoor and outdoor filter samples were collected from January 17 to February 25, 2022, in a residential area with high outdoor PM2.5 concentrations. The oxidative potential of PM2.5 was determined using the dithiothreitol-depletion assay (OPDTT). For the unoccupied house, the background indoor-to-outdoor (I/O) ratio of mass-normalized OP (OPmDTT), a measure of the intrinsic health-relevant properties of the aerosol, was less than 1 (0.53 ± 0.37), implying a loss of aerosol toxicity as air was transported indoors. This may result from transport and volatility losses driven by the large gradients in temperature (average outdoor temperature of -19°C/average indoor temperature of 21 °C) or relative humidity (average outdoor RH of 78%/average indoor RH of 11%), or both. Various indoor activities, including pellet stove use, simple cooking experiments, incense burning, and mixtures of these activities, were conducted. The experiments produced PM2.5 with a highly variable OPmDTT. PM2.5 from cooking emissions had the lowest OP values, while pellet stove PM2.5 had the highest. Correlations between volume-normalized OPDTT (OPvDTT), relevant to exposure, and indoor PM2.5 mass concentration during experiments were much lower compared to those in outdoor environments. This suggests that mass concentration alone can be a poor indicator of possible adverse effects of various indoor emissions. These findings highlight the importance of considering both the quantity of particles and sources (chemical composition), as health metrics for indoor air quality.

Overview of the Alaskan Layered Pollution and Chemical Analysis (ALPACA) Field Experiment.

The Alaskan Layered Pollution And Chemical Analysis (ALPACA) field experiment was a collaborative study designed to improve understanding of pollution sources and chemical processes during winter (cold climate and low-photochemical activity), to investigate indoor pollution, and to study dispersion of pollution as affected by frequent temperature inversions. A number of the research goals were motivated by questions raised by residents of Fairbanks, Alaska, where the study was held. This paper describes the measurement strategies and the conditions encountered during the January and February 2022 field experiment, and reports early examples of how the measurements addressed research goals, particularly those of interest to the residents. Outdoor air measurements showed high concentrations of particulate matter and pollutant gases including volatile organic carbon species. During pollution events, low winds and extremely stable atmospheric conditions trapped pollution below 73 m, an extremely shallow vertical scale. Tethered-balloon-based measurements intercepted plumes aloft, which were associated with power plant point sources through transport modeling. Because cold climate residents spend much of their time indoors, the study included an indoor air quality component, where measurements were made inside and outside a house to study infiltration and indoor sources. In the absence of indoor activities such as cooking and/or heating with a pellet stove, indoor particulate matter concentrations were lower than outdoors; however, cooking and pellet stove burns often caused higher indoor particulate matter concentrations than outdoors. The mass-normalized particulate matter oxidative potential, a health-relevant property measured here by the reactivity with dithiothreiol, of indoor particles varied by source, with cooking particles having less oxidative potential per mass than pellet stove particles.

Ets1 and IL17RA cooperate to regulate autoimmune responses and skin immunity to Staphylococcus aureus.

Introduction: Ets1 is a lymphoid-enriched transcription factor that regulates B- and Tcell functions in development and disease. Mice that lack Ets1 (Ets1 KO) develop spontaneous autoimmune disease with high levels of autoantibodies. Naïve CD4 + T cells isolated from Ets1 KO mice differentiate more readily to Th17 cells that secrete IL-17, a cytokine implicated in autoimmune disease pathogenesis. To determine if increased IL-17 production contributes to the development of autoimmunity in Ets1 KO mice, we crossed Ets1 KO mice to mice lacking the IL-17 receptor A subunit (IL17RA KO) to generate double knockout (DKO) mice. Methods: In this study, the status of the immune system of DKO and control mice was assessed utilizing ELISA, ELISpot, immunofluorescent microscopy, and flow cytometric analysis of the spleen, lymph node, skin. The transcriptome of ventral neck skin was analyzed through RNA sequencing. S. aureus clearance kinetics in in exogenously infected mice was conducted using bioluminescent S. aureus and tracked using an IVIS imaging experimental scheme. Results: We found that the absence of IL17RA signaling did not prevent or ameliorate the autoimmune phenotype of Ets1 KO mice but rather that DKO animals exhibited worse symptoms with striking increases in activated B cells and secreted autoantibodies. This was correlated with a prominent increase in the numbers of T follicular helper (Tfh) cells. In addition to the autoimmune phenotype, DKO mice also showed signs of immunodeficiency and developed spontaneous skin lesions colonized by Staphylococcus xylosus. When DKO mice were experimentally infected with Staphylococcus aureus, they were unable to clear the bacteria, suggesting a general immunodeficiency to staphylococcal species. γδ T cells are important for the control of skin staphylococcal infections. We found that mice lacking Ets1 have a complete deficiency of the γδ T-cell subset dendritic epidermal T cells (DETCs), which are involved in skin woundhealing responses, but normal numbers of other skin γδ T cells. To determine if loss of DETC combined with impaired IL-17 signaling might promote susceptibility to staph infection, we depleted DETC from IL17RA KO mice and found that the combined loss of DETC and impaired IL-17 signaling leads to an impaired clearance of the infection. Conclusions: Our studies suggest that loss of IL-17 signaling can result in enhanced autoimmunity in Ets1 deficient autoimmune-prone mice. In addition, defects in wound healing, such as that caused by loss of DETC, can cooperate with impaired IL-17 responses to lead to increased susceptibility to skin staph infections.

Staphylococcus xylosus and Staphylococcus aureus as commensals and pathogens on murine skin.

Skin ulcers, skin dermatitis and skin infections are common phenomena in colonies of laboratory mice and are often found at increased prevalence in certain immunocompromised strains. While in many cases these skin conditions are mild, in other cases they can be severe and lead to animal morbidity. Furthermore, the presence of skin infections and ulcerations can complicate the interpretation of experimental protocols, including those examining immune cell activation. Bacterial species in the genus Staphylococcus are the most common pathogens recovered from skin lesions in mice. In particular, Staphylococcus aureus and Staphylococcus xylosus have both been implicated as pathogens on murine skin. Staphylococcus aureus is a well-known pathogen of human skin, but S. xylosus skin infections in humans have not been described, indicating that there is a species-specific difference in the ability of S. xylosus to serve as a skin pathogen. The aim of this review is to summarize studies that link S. aureus and S. xylosus to skin infections of mice and to describe factors involved in their adherence to tissue and their virulence. We discuss potential differences in mouse and human skin that might underlie the ability of S. xylosus to act as a pathogen on murine skin, but not human skin. Finally, we also describe mouse mutants that have shown increased susceptibility to skin infections with staphylococcal bacteria. These mutants point to pathways that are important in the control of commensal staphylococcal bacteria. The information here may be useful to researchers who are working with mouse strains that are prone to skin infections with staphylococcal bacteria.

Semimembranosus Tendon Findings in Acute Anterior Cruciate Ligament Tears: MRI Evaluation and Associated Lesions.

BACKGROUND: The semimembranosus (SM) tendon acts as a secondary dynamic stabilizer of the knee. It restrains external rotation and anterior translation of the medial compartment. Its role in the mechanism of injury during anterior cruciate ligament (ACL) rupture is unknown. HYPOTHESIS: The bone bruise (BB) often detected at the posteromedial tibia in association with acute ACL tear may be related to the traction force from the SM tendon insertion. Magnetic resonance imaging (MRI) alterations can be detectable at the direct arm of the SM tendon in association with acute ACL injury. STUDY DESIGN: Cross-sectional study: Level of evidence, 3. METHODS: In the first study phase, 36 noninjured patients underwent knee MRI. The anatomic appearance of the SM tendon was evaluated. An imaging score for evaluating the SM tendon was developed for the purpose of the study. The intensity (in the axial or sagittal plane), morphology, and thickness of the distal SM tendon was evaluated and scored (4 total points). In the second study phase, 52 patients undergoing acute ACL reconstruction were included. Preoperative MRI was examined and scored, with documentation of BB at the posteromedial tibial plateau. Finally, arthroscopic diagnosis of a ramp lesion was confirmed. Logistic regression analysis was carried out for correlation between an altered MRI scoring system and the presence of BB at the posteromedial tibial plateau, the presence of a ramp lesion, or both. RESULTS: Interrater agreement of 100% was obtained in the noninjured cohort (ie, no alteration found in any patient). The score validation in the cohort of patients with acute ACL injury showed a Cohen κ of 0.78 (interrater agreement, 82.7%). The direct arm of the SM tendon was altered in 35 of 52 patients (67.3%). A ramp lesion of the medial meniscus was arthroscopically detected in 21 patients (40.4%). The presence of BB at the posteromedial tibial plateau was detected in 33 patients (63.5%) and at the posterior medial femoral condyle in 1 (1.9%). Correlation analysis showed a significant association of a pathologic SM score with the presence of BB at the posteromedial tibial plateau (odds ratio = 2.7; P = .001). Conversely, no correlation was observed between the pathologic score and the presence of a ramp lesion (odds ratio = 0.88; P = .578). CONCLUSION: The prevalence of pathologic findings in the direct arm of the SM tendon insertion was high in the acutely injured cohort with ACL rupture and is correlated with the presence of BB at the posteromedial tibial plateau. The main hypothesis formulated for the study was confirmed.

Mountain wetland soil carbon stocks of Huascarán National Park, Peru.

Although wetlands contain a disproportionately high amount of earth's total soil carbon, many regions are still poorly mapped and with unquantified carbon stocks. The tropical Andes contain a high concentration of wetlands consisting mostly of wet meadows and peatlands, yet their total organic carbon stocks are poorly quantified, as well as the carbon fraction that wet meadows store compared to peatlands. Therefore, our goal was to quantify how soil carbon stocks vary between wet meadows and peatlands for a previously mapped Andean region, Huascarán National Park, Peru. Our secondary goal was to test a rapid peat sampling protocol to facilitate field sampling in remote areas. We sampled soil to calculate carbon stocks of four wetland types: cushion peat, graminoid peat, cushion wet meadow, and graminoid wet meadow. Soil sampling was conducted by using a stratified randomized sampling scheme. Wet meadows were sampled to the mineral boundary using a gouge auger, and we used a combination of full peat cores and a rapid peat sampling procedure to estimate peat carbon stocks. In the lab, soils were processed for bulk density and carbon content, and total carbon stock of each core was calculated. We sampled 63 wet meadows and 42 peatlands. On a per hectare basis, carbon stocks varied strongly between peatlands (avg. 1092 MgC ha-1) and wet meadows (avg. 30 MgC ha-1). Overall, wetlands in Huascarán National Park contain 24.4 Tg of carbon with peatlands storing 97% of the total wetland carbon and wet meadows accounting for 3% of the wetland carbon in the park. In addition, our results show that rapid peat sampling can be an effective method for sampling carbon stocks in peatlands. These data are important for countries developing land use and climate change policies as well as providing a rapid assessment method for wetland carbon stock monitoring programs.

B Cell Activation Results in IKK-Dependent, but Not c-Rel- or RelA-Dependent, Decreases in Transcription of the B Cell Tolerance-Inducing Gene Ets1.

Ets1 is a key transcription factor in B cells that is required to prevent premature differentiation into Ab-secreting cells. Previously, we showed that BCR and TLR signaling downregulate Ets1 levels and that the kinases PI3K, Btk, IKK, and JNK are required for this process. PI3K is important in activating Btk by generating the membrane lipid phosphatidylinositol (3,4,5)-trisphosphate, to which Btk binds via its PH domain. Btk in turn is important in activating the IKK kinase pathway, which it does by activating phospholipase Cγ2→protein kinase Cß signaling. In this study, we have further investigated the pathways regulating Ets1 in mouse B cells. Although IKK is well known for its role in activating the canonical NF-κB pathway, IKK-mediated downregulation of Ets1 does not require either RelA or c-Rel. We also examined the potential roles of two other IKK targets that are not part of the NF-κB signaling pathway, Foxo3a and mTORC2, in regulating Ets1. We find that loss of Foxo3a or inhibition of mTORC2 does not block BCR-induced Ets1 downregulation. Therefore, these two pathways are not key IKK targets, implicating other as yet undefined IKK targets to play a role in this process.

Efficacy and utilization of intravascular ultrasound in office-based lower extremity endovascular interventions for peripheral arterial disease.

OBJECTIVES: Intravascular ultrasound (IVUS) is a uniquely objective but underutilized imaging modality in the interventional treatment of peripheral arterial disease treatment. IVUS has been shown to improve device size selection and diagnose occult pathology difficult to see with routine angiography. We hypothesize that the use of IVUS in lower extremity endovascular intervention improves accuracy in stent and balloon size selection and minimizes contrast use. METHODS: This is a retrospective case series performed at a single-institution outpatient center by two vascular surgeons from July 2016 through July 2017. We identified 94 total IVUS-assisted procedures. We collected data regarding demographics, balloon and stent size, IVUS-determined vessel diameter, pre-procedure and post-procedure ABI values, and contrast used during the procedure. An independent core laboratory was further utilized to characterize all IVUS and angiographic size vessel measurements. RESULTS: For the 94 lower extremity IVUS-assisted interventions, the average patient age was 70±9 years old, with an average contrast use of 37.1 mL of Omnipaque 300. There was substantial improvement in pre- and post-procedure ABI (0.7±0.23 to 0.94±0.21). On analysis of average intraluminal IVUS vessel diameter to balloon angioplasty used, we had a correlation in size of 0.96±0.16 in our series. Additionally, in eight instances IVUS allowed for identification of a flow-limiting dissection with subsequent stenting. CONCLUSIONS: Routine use of IVUS offers a powerful diagnostic paradigm that has the potential to significantly decrease contrast use and to improve objectivity in choosing appropriate vascular tools to maximize intra-procedural efficacy. The discovery of adverse findings not initially noticed on angiography further reinforces the value of IVUS utilization.

Source and Chemistry of Hydroxymethanesulfonate (HMS) in Fairbanks, Alaska.

Fairbanks, Alaska, is a subarctic city with fine particle (PM2.5) concentrations that exceed air quality regulations in winter due to weak dispersion caused by strong atmospheric inversions, local emissions, and the unique chemistry occurring under the cold and dark conditions. Here, we report on observations from the winters of 2020 and 2021, motivated by our pilot study that showed exceptionally high concentrations of fine particle hydroxymethanesulfonate (HMS) or related sulfur(IV) species (e.g., sulfite and bisulfite). We deployed online particle-into-liquid sampler-ion chromatography (PILS-IC) in conjunction with a suite of instruments to determine HMS precursors (HCHO, SO2) and aerosol composition in general, with the goal to characterize the sources and sinks of HMS in wintertime Fairbanks. PM2.5 HMS comprised a significant fraction of PM2.5 sulfur (26-41%) and overall PM2.5 mass concentration of 2.8-6.8% during pollution episodes, substantially higher than what has been observed in other regions, likely due to the exceptionally low temperatures. HMS peaked in January, with lower concentrations in December and February, resulting from changes in precursors and meteorological conditions. Strong correlations with inorganic sulfate and organic mass during pollution events suggest that HMS is linked to processes responsible for poor air quality episodes. These findings demonstrate unique aspects of air pollution formation in cold and humid atmospheres.

The post-traumatic meniscal extrusion, sign of meniscotibial ligament injury. A case series.

BACKGROUND: Medial meniscal extrusion (ME) has been found to be associated to anterior cruciate ligament (ACL) injury. Post-traumatic extrusion is mainly attributed to meniscotibial ligament (MTL) tear. The aim of this retrospective study was to assess the incidence of MTL tear associated with meniscal extrusion, evaluate arthroscopic findings and the associated clinical findings. HYPOTHESIS: The medial meniscal extrusion, when associated to ACL injury, is related to a tear of the MTL. PATIENTS AND METHODS: Patients who underwent to primary or revision ACL reconstruction with associated medial meniscal rise and/or meniscotibial tear or insufficiency were retrospectively identified over a 5-year period (from 2015 to 2019). Twenty-four patients were included in this study with preoperative magnetic resonance imaging (MRI) carried out at our institution Each MRI was evaluated by the senior author for the presence of meniscal extrusion and also for the additional pathology of meniscotibial ligament. Patient medical records were reviewed to obtain demographic information, including age, gender, and arthrometric evaluation of anteroposterior laxity. RESULTS: All included patients underwent arthroscopic ACL reconstruction using autograft tissue, (19 primary and in 5 revision ACL reconstruction). The mean age was 31.2 years (range: 15-57; SD: 12.3 years) at the time of surgery. ME was identified at MRI in all cases preoperatively and confirmed arthroscopically. No correlation was found between meniscal extrusion and anteroposterior translation (ρ=-0.270; p=0.202). Neither between having more than 3mm of extrusion and gender (χ2=0.80; p=0.371), acute/chronic lesion (χ2=0.91; p=0.341) and primary/revision reconstructions (χ2=0.83; p=0.364). In the last three patients, arthroscopic treatment of meniscal extrusion was carried out through outside-in repair of medial meniscus at its capsular junction. Reduction of meniscal extrusion has been verified by MRI, performed at 3-month follow-up. DISCUSSION: A high prevalence of ME was found at MRI in patients with ACL injury and MTL tear. Therefore, ME may be associated to acute or chronic ligamentous injury involving the MTL, and its tear can be considered as the main determinant of extrusion. Further research is needed to increase evidence concerning MTL incidence and surgical outcomes. LEVEL OF EVIDENCE: IV, retrospective case series.

The impact of obesity and morbid obesity on urgent/emergency colorectal resections: a regional database analysis.

BACKGROUND: The obesity rate is projected to reach 50% by 2030. Obesity may be modifiable prior to elective colorectal surgery, but there is no opportunity for weight loss when patients present for urgent/emergency operations. The impact of obesity focused on urgent/emergent colorectal operations has not been fully characterized. The study aim was to determine outcomes of obese patients who undergo urgent/emergency colorectal surgery and differences when compared with elective outcomes. METHODS: This is a retrospective cohort study of 30-day outcomes for normal (BMI 18.5-25), obese (BMI 30-39.9), and morbidly obese (BMI > 40) patients in the Michigan Surgical Quality Collaborative between 1/1/2009 and 12/31/2018. Propensity score weighting was used to derive adjusted rates for overall morbidity, mortality, and specific complications. Primary outcome was postoperative complications (any morbidity). RESULTS: The study included 5268 urgent/emergency and 10,414 elective colorectal surgery patients. Postoperative complications were significantly more common in morbidly obese and obese than the normal BMI group for both urgent/emergency (morbidly obese 42.76% vs 33.75%, p = 0.003; obese 36.46% vs 33.75%, p = 0.043) and elective (morbidly obese 18.17% vs 13.36%, p = 0.004; obese 15.45% vs 13.36%, p = 0.011) operations. Surgical site infections are were significantly more common in morbidly obese and obese BMI groups as compared to normal BMI for both urgent/emergency and elective cases. Mortality was significantly higher in the morbidly obese (14.93% vs 11.44%, p = 0.013) but not obese BMI groups as compared to the normal BMI group for urgent/emergency cases. Mortality for all groups undergoing elective operations was < 1% and with no significant differences. CONCLUSIONS: Morbid obesity and obesity are associated with complications that are largely driven by surgical site infections after both urgent/emergency and elective colorectal surgery. Obesity is a risk factor difficult to modify prior to urgent/emergency surgery. Managing complications related to obesity after colorectal surgery will be a continued challenge with projected increasing obesity rates.

A Single Institution Propensity Score Weighted Analysis of Time to Chemotherapy After Minimally Invasive Versus Open Colorectal Surgery.

BACKGROUND: Oncologic outcomes for colon cancer are optimal when chemotherapy is started within 6 to 8 weeks after surgery. The study objective was to investigate the impact of operative modality and urgency on the time interval from surgery to adjuvant chemotherapy. METHODS: This is a retrospective institutional tumor registry cohort study of open and laparoscopic/robotic colorectal resections for stage II-IV cancer between April 2010 and January 2018. Primary outcome was time from surgery to chemotherapy. Predictor variables were adjusted for imbalances by propensity score weighting. RESULTS: A total of 220 patients met inclusion criteria: 171 elective (108 laparoscopic/robotic and 63 open) and 49 urgent colectomies. After propensity score weighting, there was no significant difference in time to chemotherapy between elective minimally invasive and open surgical approaches (48 days vs. 58 days, P = .187). Only 68.9% of minimally invasive and 50.8% of open colectomy patients started chemotherapy within 8 weeks of surgery. There was a significant difference (P = .037) among surgical sites with rectal resections having the longest (55 days), and right colectomies having the shortest (46 days), time to chemotherapy. Patients who had urgent operations had significantly longer hospital length of stay (P < .001) and higher post-discharge emergency department visit rates (P < .001) than the elective operation group. However, there was no significant difference in time to chemotherapy. DISCUSSION: Neither operative modality nor operative urgency resulted in a significant difference in postoperative time to initiating chemotherapy. Future efforts should be focused on identifying postoperative recovery criteria and optimum multidisciplinary communication methods that allow recovered patients to start chemotherapy sooner.

A Single-Institution Analysis of Targeted Colorectal Surgery Enhanced Recovery Pathway Strategies That Decrease Readmissions.

BACKGROUND: Decreasing readmissions is an important quality improvement strategy. Targeted interventions that effectively decrease readmissions have not been fully investigated and standardized. OBJECTIVE: The purpose of this study was to assess the effectiveness of interventions designed to decrease readmissions after colorectal surgery. DESIGN: This was a retrospective comparison of patients before and after the implementation of interventions. SETTING: This study was conducted at a single institution dedicated enhanced recovery pathway colorectal surgery service. PATIENTS: The study group received quality review interventions that were designed to decrease readmissions: preadmission class upgrades, a mobile phone app, a pharmacist-led pain management strategy, and an early postdischarge clinic. The control group was composed of enhanced recovery patients before the interventions. Propensity score weighting was used to adjust patient characteristics and predictors for imbalances. MAIN OUTCOME MEASURE: The primary outcome was 30-day readmissions. Secondary outcomes included emergency department visits. RESULTS: There were 1052 patients in the preintervention group and 668 patients in the postintervention group. After propensity score weighting, the postintervention cohort had a significantly lower readmission rate (9.98% vs 17.82%, p < 0.001) and emergency department visit rate (14.58% vs 23.15%, p < 0.001) than the preintervention group, and surgical site infection type I/II was significantly decreased as a readmission diagnosis (9.46% vs 2.43%, p = 0.043). Median time to readmission was 6 (interquartile 3-11) days in the preintervention group and 8 (3-17) days in the postintervention group (p = 0.21). Ileus, acute kidney injury, and surgical site infection type III were common reasons for readmissions and emergency department visits. LIMITATIONS: A single-institution study may not be generalizable. CONCLUSION: Readmission bundles composed of targeted interventions are associated with a decrease in readmissions and emergency department visits after enhanced recovery colorectal surgery. Bundle composition may be institution dependent. Further study and refinement of bundle components are required as next-step quality metric improvements. See Video Abstract at http://links.lww.com/DCR/B849. ANLISIS EN UNA SOLA INSTITUCIN DE LAS CIRUGAS COLORECTALES CON VAS DE RECUPERACIN DIRIGIDA AUMENTADA QUE REDUCEN LOS REINGRESOS: ANTECEDENTES:La reducción de los reingresos es una importante estrategia de mejora de la calidad. Las intervenciones dirigidas que reducen eficazmente los reingresos no se han investigado ni estandarizado por completo.OBJETIVO:El propósito de este estudio fue evaluar la efectividad de las intervenciones diseñadas para disminuir los reingresos después de la cirugía colorrectal.DISEÑO:Comparación retrospectiva de pacientes antes y después de la implementación de las intervenciones.ESCENARIO:Una sola institución dedicada al Servicio de cirugía colorrectal con vías de recuperación dirigida aumentadaPACIENTES:El grupo de estudio recibió intervenciones de revisión de calidad que fueron diseñadas para disminuir los reingresos: actualizaciones de clases previas a la admisión, una aplicación para teléfono móvil, una estrategia de manejo del dolor dirigida por farmacéuticos y alta temprana de la clínica. El grupo de control estaba compuesto por pacientes con recuperación mejorada antes de las intervenciones. Se utilizó la ponderación del puntaje de propensión para ajustar las características del paciente y los predictores de los desequilibrios.PARÁMETRO DE RESULTADO PRINCIPAL:El resultado primario fueron los reingresos a los 30 días. Los resultados secundarios incluyeron visitas al servicio de urgencias.RESULTADOS:Hubo 1052 pacientes en el grupo de preintervención y 668 pacientes en el grupo de posintervención. Después de la ponderación del puntaje de propensión, la cohorte posterior a la intervención tuvo una tasa de reingreso significativamente menor (9,98% frente a 17,82%, p <0,001) y una tasa de visitas al servicio de urgencias (14,58% frente a 23,15%, p <0,001) que el grupo de preintervención y la infección del sitio quirúrgico tipo I / II se redujo significativamente como diagnóstico de reingreso (9,46% frente a 2,43%, p = 0,043). La mediana de tiempo hasta la readmisión fue de 6 [IQR 3, 11] días en el grupo de preintervención y de 8 [3, 17] días en el grupo de posintervención (p = 0,21). El íleo, la lesión renal aguda y la infección del sitio quirúrgico tipo III fueron motivos frecuentes de reingresos y visitas al servicio de urgencias.LIMITACIONES:El estudio de una sola institución puede no ser generalizable.CONCLUSIÓNES:Los paquetes de readmisión compuestos por intervenciones dirigidas se asocian con una disminución en las readmisiones y las visitas al departamento de emergencias después de una cirugía colorrectal con vías de recuperación dirigida aumentada. La composición del paquete puede depender de la institución. Se requieren más estudios y refinamientos de los componentes del paquete como siguiente paso de mejora de la métrica de calidad. Consulte Video Resumen en http://links.lww.com/DCR/B849. (Traducción-Dr Yolanda Colorado).

Anomalous insertion of anterior and posterior horns of medial meniscus. Case report.

BACKGROUND: Anatomical variations of the attachment of medial meniscus are a common finding. However, anomalies of the posterior horn are extremely rare. Only two cases of posterior root anomaly have been described prior to the routine use of arthroscopy for evaluation and treatment of meniscal pathology. In this report, we present an anomaly of both the anterior and posterior roots of the medial meniscus that posed both a diagnostic and therapeutic dilemma. CASE PRESENTATION: The patient is young male soccer player who is currently 16 years of age and began having the atraumatic onset of pain and symptoms that limited performance starting at age 14 and was referred for failure of response to nonoperative treatment. Diagnostic arthroscopy revealed the presence of an anteromedial meniscofemoral ligament whereas the posterior root showed no bony attachment. The radiographic and arthroscopic findings are described. The clinical decision was made after to proceed with observation, reassurance, and gradual return to full activity with physiotherapy guidance. DISCUSSION AND CONCLUSION: The absence of injury, the mild complaints reported by the patient, his age, skeletal immaturity, and remaining growth led us to adopt a conservative approach to treating this anatomic variant and currently the patient is able to participate fully in sports without symptoms or restrictions.

Postoperative Pain After Enhanced Recovery Pathway Robotic Colon and Rectal Surgery: Does Specimen Extraction Site Matter?

BACKGROUND: The current opioid crisis has motivated surgeons to critically evaluate ways to balance postoperative pain while decreasing opioid use and thereby reducing opioids available for community diversion. The longest incision for robotic colorectal surgery is the specimen extraction site incision. Intracorporeal techniques allow specimen extraction to be at any location. OBJECTIVE: This study was designed to determine whether the Pfannenstiel location is associated with less pain and opioid use than other abdominal wall specimen extraction sites. DESIGN: This was a retrospective cohort study. SETTINGS: The study was conducted with a prospectively maintained colorectal surgery database (July 2018 through October 2019). PATIENTS: Patients with enhanced recovery robotic colorectal resections with specimen extraction were included. MAIN OUTCOME MEASURES: Propensity score weighting was used to derive adjusted rates for numeric pain scores, inpatient opioid use, opioids prescribed at discharge, opioid refills after discharge, and other related outcomes. For comparing outcomes between groups, p values were calculated using weighted χ2, Fisher exact, and t tests. RESULTS: There were 137 cases (70.9%) with Pfannenstiel extraction site incisions and 56 (29.0%) at other locations (7 midline, 49 off-midline). There was no significant difference in transversus abdominis plane blocks and epidural analgesia use between groups. Numeric pain scores, overall benefit of analgesia scores, inpatient postoperative opioid use, opioids prescribed at discharge and taken after discharge, and opioid refills were not significantly different between groups. Nonopioid pain analgesics (acetaminophen, nonsteroidal anti-inflammatory drugs, and gabapentin) prescribed at discharge were significantly less in the Pfannenstiel group (90.19% vs 98.45%; p = 0.006). Postoperative complications and readmissions were not different between groups. LIMITATIONS: This study was conducted at a single institution. CONCLUSIONS: The Pfannenstiel incision as the specimen extraction site choice in minimally invasive surgery is associated with similar postoperative pain and opioid use as extraction sites in other locations for patients having robotic colorectal resections. Specimen extraction sites may be chosen based on patient factors other than pain and opioid use. See Video Abstract at http://links.lww.com/DCR/B495. DOLOR POSTOPERATORIO DESPUS DE VAS DE RECUPERACIN MEJORADA EN CIRUGA ROBTICA DE COLON Y RECTO IMPORTA EL LUGAR DE EXTRACCIN DE LA MUESTRA: ANTECEDENTES:La actual crisis de opioides ha motivado a los cirujanos a evaluar críticamente, formas para equilibrar el dolor postoperatorio, disminuyendo el uso de opioides y por lo tanto, disminuyendo opioides disponibles para el desvío comunitario. La incisión más amplia en cirugía colorrectal robótica, es la incisión del sitio de extracción de la muestra. Las técnicas intracorpóreas permiten que la extracción de la muestra se realice en cualquier sitio.OBJETIVO:El estudio fue diseñado para determinar si la ubicación del Pfannenstiel está asociada con menos dolor y uso de opioides, a otros sitios de extracción de la muestra en la pared abdominal.DISEÑO:Estudio de cohorte retrospectivo.AJUSTES:Estudio de base de datos de cirugía colorrectal mantenida prospectivamente (7/2018 a 10/2019).PACIENTES:Se incluyeron resecciones robóticas colorrectales con recuperación mejorada y extracción de muestras.PRINCIPALES MEDIDAS DE RESULTADO:Se utilizó la ponderación del puntaje de propensión para derivar las tasas ajustadas para los puntajes numéricos de dolor, uso de opioides en pacientes hospitalizados, opioides recetados al alta, recarga de opioides después del alta y otros resultados relacionados. Para comparar los resultados entre los grupos, los valores p se calcularon utilizando chi-cuadrado ponderado, exacto de Fisher y pruebas t.RESULTADOS:Hubo 137 (70,9%) casos con incisiones en el sitio de extracción de Pfannenstiel y 56 (29,0%) en otras localizaciones (7 en la línea media, 49 fuera de la línea media). No hubo diferencias significativas en los bloqueos del plano transverso del abdomen y el uso de analgesia epidural entre los grupos. Las puntuaciones numéricas de dolor, puntuaciones de beneficio general de la analgesia, uso postoperatorio de opioides en pacientes hospitalizados, opioides recetados al alta y tomados después del alta, y las recargas de opioides, no fueron significativamente diferentes entre los grupos. Los analgésicos no opioides (acetaminofén, antiinflamatorios no esteroideos, gabapentina) prescritos al alta, fueron significativamente menores en el grupo de Pfannenstiel (90,19% frente a 98,45%, p = 0,006). Las complicaciones postoperatorias y los reingresos, no fueron diferentes entre los grupos.LIMITACIONES:Una sola institución.CONCLUSIÓN:La incisión de Pfannenstiel como sitio de extracción de la muestra en cirugía mínimamente invasiva, se asocia con dolor postoperatorio y uso de opioides similar, a otros sitios de extracción en pacientes sometidos a resecciones robóticas colorrectales. Sitios de extracción de la muestra, pueden elegirse en función de factores del paciente distintos al dolor y uso de opioides. Consulte Video Resumen en http://links.lww.com/DCR/B495.).

Bacterial infections in lupus: Roles in promoting immune activation and in pathogenesis of the disease.

BACKGROUND: Bacterial infections of the lung, skin, bloodstream and other tissues are common in patients with systemic lupus erythematosus (lupus) and are often more severe and invasive than similar infections in control populations. A variety of studies have explored the changes in bacterial abundance in lupus patients, the rates of infection and the influence of particular bacterial species on disease progression, using both human patient samples and mouse models of lupus. OBJECTIVE: The aim of this review is to summarize human and mouse studies that describe changes in the bacterial microbiome in lupus, the role of a leaky gut in stimulating inflammation, identification of specific bacterial species associated with lupus, and the potential roles of certain common bacterial infections in promoting lupus progression. METHODS: Information was collected using searches of the Pubmed database for articles relevant to bacterial infections in lupus and to microbiome changes associated with lupus. RESULTS: The reviewed studies demonstrate significant changes in the bacterial microbiome of lupus patients as compared to control subjects and in lupus-prone mice compared to control mice. Furthermore, there is evidence supporting the existence of a leaky gut in lupus patients and in lupus-prone mice. This leaky gut may allow live bacteria or bacterial components to enter the circulation and cause inflammation. Invasive bacterial infections are more common and often more severe in lupus patients. These include infections caused by Staphylococcus aureus, Salmonella enterica, Escherichia coli, Streptococcus pneumoniae and mycobacteria. These bacterial infections can trigger increased immune activation and inflammation, potentially stimulating activation of autoreactive lymphocytes and leading to worsening of lupus symptoms. CONCLUSIONS: Together, the evidence suggests that lupus predisposes to infection, while infection may trigger worsening lupus, leading to a feedback loop that may reinforce autoimmune symptoms.

Forest density intensifies the importance of snowpack to growth in water-limited pine forests.

Warming climate and resulting declines in seasonal snowpack have been associated with drought stress and tree mortality in seasonally snow-covered watersheds worldwide. Meanwhile, increasing forest density has further exacerbated drought stress due to intensified tree-tree competition. Using a uniquely detailed data set of population-level forest growth (n = 2,495 sampled trees), we examined how inter-annual variability in growth relates to snow volume across a range of forest densities (e.g., competitive environments) in sites spanning a broad aridity gradient across the United States. Forest growth was positively related to snowpack in water-limited forests located at low latitude, and this relationship was intensified by forest density. However, forest growth was negatively related to snowpack in a higher latitude more energy-limited forest, and this relationship did not interact with forest density. Future reductions in snowpack may have contrasting consequences, as growth may respond positively in energy-limited forests and negatively in water-limited forests; however, these declines may be mitigated by reducing stand density through forest thinning.

Fenestrated repair improves perioperative outcomes but lacks a hospital volume association for complex abdominal aortic aneurysms.

BACKGROUND: Complex abdominal aortic aneurysms (AAAs) have traditionally been treated with an open surgical repair (OSR). During the past decade, fenestrated endovascular aneurysm repair (FEVAR) has emerged as a viable option. Hospital procedural volume to outcome relationship for OSR of complex AAAs has been well established, but the impact of procedural volume on FEVAR outcomes remains undefined. This study investigated the outcomes of OSR and FEVAR for the treatment of complex AAAs and examined the hospital volume-outcome relationship for these procedures. METHODS: A retrospective review of a statewide vascular surgery registry was queried for all patients between 2012 and 2018 who underwent elective repair of a juxtarenal/pararenal AAA with FEVAR or OSR. The primary outcomes were 30-day mortality, myocardial infarction, and new dialysis. Secondary end points included postoperative pneumonia, renal dysfunction (creatine concentration increase of >2 mg/dL from preoperative baseline), major bleeding, early procedural complications, length of stay, and need for reintervention. To evaluate procedural volume-outcomes relationship, hospitals were stratified into low- and high-volume aortic centers based on a FEVAR annual procedural volume. To account for baseline differences, we calculated propensity scores and employed inverse probability of treatment weighting in comparing outcomes between treatment groups. RESULTS: A total of 589 patients underwent FEVAR (n = 186) or OSR (n = 403) for a complex AAA. After adjustment, OSR was associated with higher rates of 30-day mortality (10.7% vs 2.9%; P < .001) and need for dialysis (11.3% vs 1.8; P < .001). Postoperative pneumonia (6.8% vs 0.3%; P < .001) and need for transfusion (39.4% vs 10.4%; P < .001) were also significantly higher in the OSR cohort. The median length of stay for OSR and FEVAR was 9 days and 3 days, respectively. For those who underwent FEVAR, endoleaks were present in 12.1% of patients at 30 days and 6.1% of patients at 1 year, with the majority being type II. With a median follow-up period of 331 days (229-378 days), 1% of FEVAR patients required a secondary procedure, and there were no FEVAR conversions to an open aortic repair. Hospitals were divided into low- and high-volume aortic centers based on their annual FEVAR volume of complex AAAs. After adjustment, hospital FEVAR procedural volume was not associated with 30-day mortality or myocardial infarction. CONCLUSIONS: FEVAR was associated with lower perioperative morbidity and mortality compared with OSR for the management of complex AAAs. Procedural FEVAR volume outcome analysis suggests limited differences in 30-day morbidity, although long-term durability warrants further research.

Recurrence of Acute Right Colon Diverticulitis Following Nonoperative Management: A Systematic Review and Meta-analysis.

BACKGROUND: There are currently no guidelines on the management of right colon diverticulitis. Treatment options have been extrapolated from the management of left-sided diverticulitis. Gaining knowledge of the risk and morbidity of diverticulitis recurrence is integral to weighing the benefit of elective surgery for right-sided diverticulitis. OBJECTIVE: The purpose of this study was to summarize the recurrence rate and the morbidity of recurrence of Hinchey classification I/II, right-sided diverticulitis following nonoperative management. DATA SOURCES: PubMed, EMBASE, and Cochrane Database of Collected Reviews were searched up to June 2019. STUDY SELECTION: Observational cohort studies evaluating outcomes following nonoperative management were reviewed. No randomized controlled trials were available. INTERVENTIONS: Intravenous antibiotics with or without percutaneous drainage of associated abscess were administered. MAIN OUTCOME MEASURES: The primary outcomes measured were the recurrence rate and morbidity associated with recurrence. Two independent investigators extracted data. The rates of recurrence were pooled by using a random-effects model. RESULTS: There were 1584 adult participants from a total of 11 studies (9 retrospective cohort and 2 prospective cohort studies) included in the analysis. Over a median follow-up period of 34.2 months, the pooled recurrence rate was 12% (95% CI, 10%-15%). Twenty of 202 patients (9.9%) required urgent surgery at the time of first recurrence. There was no mortality. Subset analysis excluding 3 studies that included percutaneous drainage as a nonoperative treatment option did not change the recurrence rate (12% (95% CI, 9%-15%)) or heterogeneity. Funnel plot assessment revealed no publication bias. LIMITATIONS: There were no randomized controlled trials available. The statistical heterogeneity was moderate (I = 46%). CONCLUSIONS: Nonoperative management of Hinchey I/II right-sided diverticulitis is safe and feasible. The recurrence rate is relatively low, and complications that require urgent operation are uncommon. PROSPERO: CRD42019131673.