Citations

Destabilized heme proteins release heme, and free heme is toxic. Heme is now recognized as an agonist for the Toll-like receptor-4 (TLR4) receptor. This study examined whether the TLR4 receptor mediates the nephrotoxicity of heme, specifically, the effects of heme on renal blood flow and inflammatory responses. We blocked TLR4 signaling by the specific antagonist TAK-242. Intravenous administration of heme to mice promptly reduced renal blood flow, an effect attenuated by TAK-242. In vitro, TAK-242 reduced heme-elicited activation of NF-κB and its downstream gene monocyte chemoattractant protein-1(MCP-1); in contrast, TAK-242 failed to reduce heme-induced activation of the anti-inflammatory transcription factor Nrf2 and its downstream gene heme oxygenase-1 (HO-1). TAK-242 did not reduce heme-induced renal MCP-1 upregulation in vivo. TAK-242 did not reduce dysfunction and histological injury in the glycerol model of heme protein-induced acute kidney injury (AKI), findings corroborated by studies in TLR4+/+ and TLR4−/− mice. We conclude that 1) acute heme-mediated renal vasoconstriction occurs through TLR4 signaling; 2) proinflammatory effects of heme in renal epithelial cells involve TLR4 signaling, whereas the anti-inflammatory effects of heme do not; 3) TLR4 signaling does not mediate the proinflammatory effects of heme in the kidney; and 4) major mechanisms underlying glycerol-induced, heme protein-mediated AKI do not involve TLR4 signaling. These findings in the glycerol model are in stark contrast with findings in virtually all other AKI models studied to date and emphasize the importance of TLR4-independent pathways of heme protein-mediated injury in this model. Finally, these studies urge caution when using observations derived in vitro to predict what occurs in vivo.

OBJECTIVEIn this analysis the authors compare the characteristics of smokers to nonsmokers using demographic, socioeconomic, and comorbidity variables. They also investigate which of these characteristics are most strongly associated with smoking status. Finally, the authors investigate whether the association between known patient risk factors and disability outcome is differentially modified by patient smoking status for those who have undergone surgery for lumbar degeneration.METHODSA total of 7547 patients undergoing degenerative lumbar surgery were entered into a prospective multicenter registry (Quality Outcomes Database [QOD]). A retrospective analysis of the prospectively collected data was conducted. Patients were dichotomized as smokers (current smokers) and nonsmokers. Multivariable logistic regression analysis fitted for patient smoking status and subsequent measurement of variable importance was performed to identify the strongest patient characteristics associated with smoking status. Multivariable linear regression models fitted for 12-month Oswestry Disability Index (ODI) scores in subsets of smokers and nonsmokers was performed to investigate whether differential effects of risk factors by smoking status might be present.RESULTSIn total, 18% (n = 1365) of patients were smokers and 82% (n = 6182) were nonsmokers. In a multivariable logistic regression analysis, the factors significantly associated with patients’ smoking status were sex (p < 0.0001), age (p < 0.0001), body mass index (p < 0.0001), educational status (p < 0.0001), insurance status (p < 0.001), and employment/occupation (p = 0.0024). Patients with diabetes had lowers odds of being a smoker (p = 0.0008), while patients with coronary artery disease had greater odds of being a smoker (p = 0.044). Patients’ propensity for smoking was also significantly associated with higher American Society of Anesthesiologists (ASA) class (p < 0.0001), anterior-alone surgical approach (p = 0.018), greater number of levels (p = 0.0246), decompression only (p = 0.0001), and higher baseline ODI score (p < 0.0001). In a multivariable proportional odds logistic regression model, the adjusted odds ratio of risk factors and direction of improvement in 12-month ODI scores remained similar between the subsets of smokers and nonsmokers.CONCLUSIONSUsing a large, national, multiinstitutional registry, the authors described the profile of patients who undergo lumbar spine surgery and its association with their smoking status. Compared with nonsmokers, smokers were younger, male, nondiabetic, nonobese patients presenting with leg pain more so than back pain, with higher ASA classes, higher disability, less education, more likely to be unemployed, and with Medicaid/uninsured insurance status. Smoking status did not affect the association between these risk factors and 12-month ODI outcome, suggesting that interventions for modifiable risk factors are equally efficacious between smokers and nonsmokers.

Necrotizing fasciitis is a fulminant soft tissue infection characterized by rapid progression and high mortality. Rituximab is a generally well-tolerated immunosuppresive medication used for B-cell malignancies and some rheumatological disorders. We report a case of a 69-year-old male with chronic lymphocytic leukemia who suffered necrotizing fasciitis of his left lower extremity secondary to Clostridium septicum 7 weeks after treatment with rituximab. Despite immediate intravenous antimicrobial therapy and emergent fasciotomy with extensive debridement, his hospital course was complicated by septic shock and he required an above-the-knee amputation. Physicians need to be aware of the possibility of necrotizing fasciitis in patients presenting with skin infections after rituximab therapy.

Abstract Androgen receptor (AR) signaling is a key driver of prostate cancer, and androgen-deprivation therapy (ADT) is a standard treatment for patients with advanced and metastatic disease. However, patients receiving ADT eventually develop incurable castration-resistant prostate cancer (CRPC). Here, we report that the chromatin modifier LSD1, an important regulator of AR transcriptional activity, undergoes epigenetic reprogramming in CRPC. LSD1 reprogramming in this setting activated a subset of cell-cycle genes, including CENPE, a centromere binding protein and mitotic kinesin. CENPE was regulated by the co-binding of LSD1 and AR to its promoter, which was associated with loss of RB1 in CRPC. Notably, genetic deletion or pharmacological inhibition of CENPE significantly decreases tumor growth. Our findings show how LSD1-mediated epigenetic reprogramming drives CRPC, and they offer a mechanistic rationale for its therapeutic targeting in this disease. Cancer Res; 77(20); 5479–90. ©2017 AACR.

Objective Measurement of motivation and cognitive load has potential value in health professions education. Our objective was to evaluate the validity of scores from Dweck's Implicit Theories of Intelligence Scale ( ITIS ), Elliot's Achievement Goal Questionnaire‐Revised ( AGQ ‐R) and Leppink's cognitive load index ( CLI ). Methods This was a validity study evaluating internal structure using reliability and factor analysis, and relationships with other variables using the multitrait‐multimethod matrix. Two hundred and thirty‐two secondary school students participated in a medical simulation‐based training activity at an academic medical center. Pre‐activity ITIS (implicit theory [mindset] domains: incremental, entity) and AGQ ‐R (achievement goal domains: mastery‐approach, mastery‐avoidance, performance‐approach, performance‐avoidance), post‐activity CLI (cognitive load domains: intrinsic, extrinsic, germane) and task persistence (self‐directed repetitions on a laparoscopic surgery task) were measured. Results Internal consistency reliability (Cronbach's alpha) was > 0.70 for all domain scores except AGQ ‐R performance‐avoidance (alpha 0.68) and CLI extrinsic load (alpha 0.64). Confirmatory factor analysis of ITIS and CLI scores demonstrated acceptable model fit. Confirmatory factor analysis of AGQ ‐R scores demonstrated borderline fit, and exploratory factor analysis suggested a three‐domain model for achievement goals (mastery‐approach, performance and avoidance). Correlations among scores from conceptually‐related domains generally aligned with expectations, as follows: ITIS incremental and entity, r = −0.52; AGQ ‐R mastery‐avoidance and performance‐avoidance, r = 0.71; mastery‐approach and performance‐approach, r = 0.55; performance‐approach and performance‐avoidance, r = 0.43; mastery‐approach and mastery‐avoidance, r = 0.36; CLI germane and extrinsic, r = −0.35; ITIS incremental and AGQ ‐R mastery‐approach, r = 0.34; ITIS incremental and CLI germane, r = 0.44; AGQ ‐R mastery‐approach and CLI germane, r = 0.48 (all p < 0.001). We found no correlation between the number of task repetitions (i.e. persistence) and mastery‐approach scores, r = −0.01. Conclusions ITIS and CLI scores had appropriate internal structures and relationships with other variables. AGQ ‐R scores fit a three‐factor (not four‐factor) model that collapsed avoidance into one domain, although relationships of other variables with the original four domain scores generally aligned with expectations. Mastery goals are positively correlated with germane cognitive load.

Abstract Since the publication of the Tokyo Guidelines in 2007 and their revision in 2013, appropriate management for acute cholecystitis has been more clearly established. Since the last revision, several manuscripts, especially for alternative endoscopic techniques, have been reported; therefore, additional evaluation and refinement of the 2013 Guidelines is required. We describe a standard drainage method for surgically high‐risk patients with acute cholecystitis and the latest developed endoscopic gallbladder drainage techniques described in the updated Tokyo Guidelines 2018 ( TG 18). Our study confirmed that percutaneous transhepatic gallbladder drainage should be considered the first alternative to surgical intervention in surgically high‐risk patients with acute cholecystitis. Also, endoscopic transpapillary gallbladder drainage or endoscopic ultrasound‐guided gallbladder drainage can be considered in high‐volume institutes by skilled endoscopists. In the endoscopic transpapillary approach, either endoscopic naso‐gallbladder drainage or gallbladder stenting can be considered for gallbladder drainage. We also introduce special techniques and the latest outcomes of endoscopic ultrasound‐guided gallbladder drainage studies. Free full articles and mobile app of TG18 are available at: http://www.jshbps.jp/modules/en/index.php?content_id=47 . Related clinical questions and references are also included.

AbstractThe treatment of peripheral nerve injuries remains a major problem worldwide despite the availability of a number of Food and Drug Administration (FDA) approved devices which fail to match the efficacy of autografts. Different strategies are used to improve regeneration and functional recovery using biomaterial nerve conduits. However, there is little investigation of the transcriptomic and proteomic changes which occur as a result of these interventions, particularly regarding transection injuries. This study explores differences between autograft‐mediated repair and conduit‐material‐mediated repair of peripheral nerve injuries to understand fundamental differences in their repair mechanisms at the proteomics level at the proximal, middle, and distal components in the early stages of repair. Pathway analysis demonstrates that each material selectively activates different regenerative pathways and alters different biological functions spatially throughout the biomaterial conduits. The analysis highlights some of the deficiencies in conduit‐mediated repair in comparison to autograft (e.g., recycling of myelin and cholesterol, reduction in reactive oxygen species, and higher expression of regenerative proteins). These findings thus suggest that by supplementing the expression of these proteins on the biomaterial of choice, this study can potentially attain regeneration equivalent to autograft. This approach paves the way for incorporating future biomaterial‐specific functionalities in nerve guidance conduits.