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Introduction Generative artificial intelligence (AI) chatbots, like ChatGPT, have become more competent and prevalent, making their role in patient education more salient. This study aimed to compare the educational utility of six AI chatbots by quantifying the readability and quality of their answers to common patient questions about clavicle fracture management. Methods ChatGPT 4, ChatGPT 4o, Gemini 1.0, Gemini 1.5 Pro, Microsoft Copilot, and Perplexity were used with no prior training. Ten representative patient questions about clavicle fractures were posed to each model. The readability of AI responses was measured using Flesch-Kincaid Reading Grade Level, Gunning Fog, and Simple Measure of Gobbledygook (SMOG). Six orthopedists blindly graded the response quality of each model using the DISCERN criteria. Both metrics were analyzed via the Kruskal-Wallis test. Results No statistically significant difference was found among the readability of the six models. Microsoft Copilot (70.33±7.74) and Perplexity (71.83±7.57) demonstrated statistically significant higher DISCERN scores than ChatGPT 4 (56.67±7.15) and Gemini 1.5 Pro (51.00±8.94) with similar findings seen between Gemini 1.0 (68.00±6.42) and Gemini 1.5 Pro. The mean overall quality (question 16, DISCERN) of each model was rated at or above average (range, 3-4.4). Conclusion The findings suggest generative AI models have the capability to serve as supplementary patient education materials. With equal readability and overall high quality, Microsoft Copilot and Perplexity may be implicated as chatbots with the most educational utility regarding surgical intervention for clavicle fractures., Competing Interests: Human subjects: All authors have confirmed that this study did not involve human participants or tissue. Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: Joseph G. Elsissy (JGE), MD is a consultant for Johnson and Johnson. JGE is a consultant for Arbutus Medical. Brian A. Schneiderman, MD is a consultant for Globus Medical., (Copyright © 2025, Giammanco et al.)

Objectives: Does marijuana smoking increase the risk of surgical site infection (SSI) after open reduction and internal fixation of fractures?, Design: Retrospective., Setting: Single academic level 1 trauma center in Southern California., Patient Selection Criteria: Adult patients who underwent open treatment for closed fractures between January 2009 and December 2021, had hardware placed, and had at least 6 months of postoperative follow-up., Outcome Measures and Comparisons: Risk factors associated with the development of SSI were compared between current inhalational marijuana users and nonmarijuana users., Results: Complete data were available on 4802 patients after exclusion of 82 who did not have a complete variable set. At the time of surgery, 24% (1133 patients) were current users of marijuana. At the final follow-up (minimum 6 months), there was a 1.6% infection rate (75 patients). The average age of the infection-free group was 46.1 ± 23.1 years, and the average age of the SSI group was 47.0 ± 20.3 (P = 0.73) years. In total, 2703 patients (57%) in the infection-free group were male compared with 48 (64%) in the SSI group (P = 0.49). On multivariate analysis, longer operative times (OR 1.002 [95% CI, 1.001-1.004]), diabetic status (OR 2.084 [95% CI, 1.225-3.547]), and current tobacco use (OR 2.493 [95% CI, 1.514-4.106]) (P < 0.01 for all) were associated with an increased risk of SSI; however, current marijuana use was not (OR 0.678 [95% CI, 0.228-2.013], P = 0.48)., Conclusions: Tobacco use, diabetes, and longer operative times were associated with the development of SSI after open reduction and internal fixation of fractures; however, marijuana smoking was not shown to be associated with the development of SSI., Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence., Competing Interests: The authors report no conflict of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Case: We present a case of a 39-year-old woman at 23 weeks gestation who sustained traumatic both-column acetabular fracture and protrusio acetabuli, managed with initial traction and delayed total hip arthroplasty (THA) until after cesarean section delivery., Conclusion: Initial skeletal traction with subsequent delayed THA may be a viable treatment option in select pregnant female patients who sustain both-column acetabular fractures. Interdisciplinary collaboration is necessary to optimize maternal-fetal health and provide patient education of procedural risk to enable informed decision making., Competing Interests: Disclosure: The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article (http://links.lww.com/JBJSCC/C408)., (Copyright © 2024 by The Journal of Bone and Joint Surgery, Incorporated.)

Introduction: Hip fractures are life-changing injuries with associated one-year mortality up to 30%. Five locations in the world have been termed "blue zones," where the longevity of the population is markedly higher than that of surrounding areas and there are 10 times more centenarians. The United States has one blue zone (Loma Linda, California), which is believed to be because of the lifestyle of the Seventh-day Adventist population living there. We hypothesized that patients from the blue zone experience low-energy, frailty-driven, osteoporotic hip fractures later in life and an increased postinjury longevity relative to non-blue zone control subjects., Methods: A review of patients treated for hip fracture between January 2010 and August 2020 from a single institution was conducted. Demographic data were collected, and the end point of mortality was assessed using death registry information, queried in April 2024. Groups were divided into blue zone and non-blue zone. Statistical analysis was conducted with P < 0.05 considered significant., Results: Complete data were available for 1,032 patients. The blue zone cohort sustained low-energy hip fractures 12 years later in life (83.2 versus 71.1, P < 0.01). Propensity score matching was used to account for this difference. After propensity score matching, age, body mass index, American Society of Anesthesiologists score, surgery performed, sex, mechanism, ethnicity, diabetes, chronic obstructive pulmonary disease, CHF, chronic kidney disease grade, dementia, surgical time, and drug/tobacco/marijuana use were similar between groups. Blue zone patients had lower mortality at both 1 and 2 years postoperatively (12% versus 24%, P = 0.03 and 20% versus 33%, P = 0.03, respectively), had more hypertension (76% versus 62%, P = 0.03), reported lower alcohol use (7% versus 20%, P < 0.01), and included more Seventh-day Adventists (64% versus 15%, P < 0.01)., Conclusion: The blue zone lifestyle affected the onset of frailty and delayed osteoporotic hip fracture by 12 years in this propensity-matched cohort study. Postoperative mortality was also markedly lower in the blue zone cohort., (Copyright © 2024 by the American Academy of Orthopaedic Surgeons.)

Chronic stress and alcohol (ethanol) use are highly interrelated and can change an individual's behavior through molecular adaptations that do not change the DNA sequence, but instead change gene expression. A recent wealth of research has found that these nongenomic changes can be transmitted across generations, which could partially account for the "missing heritability" observed in genome-wide association studies of alcohol use disorder and other stress-related neuropsychiatric disorders. In this review, we summarize the molecular and behavioral outcomes of nongenomic inheritance of chronic stress and ethanol exposure and the germline mechanisms that could give rise to this heritability. In doing so, we outline the need for further research to: (1) Investigate individual germline mechanisms of paternal, maternal, and biparental nongenomic chronic stress- and ethanol-related inheritance; (2) Synthesize and dissect cross-generational chronic stress and ethanol exposure; (3) Determine cross-generational molecular outcomes of preconception ethanol exposure that contribute to alcohol-related disease risk, using cancer as an example. A detailed understanding of the cross-generational nongenomic effects of stress and/or ethanol will yield novel insight into the impact of ancestral perturbations on disease risk across generations and uncover actionable targets to improve human health., Competing Interests: None., (© 2023 The Authors.)

Introduction: Little is known about the perioperative management of Pediculus capitis (lice) infestations, including risk of contamination to the sterile field, whether to delay surgery, and optimal time to treat and/or operate., Case Report: Two identical twin patients presented for elective in situ percutaneous pinning of chronic slipped capital femoral epiphyses. Active pediculosis capitis was noted intraoperatively by the anesthesia team during the first patient's surgery. Meticulous examination of the sterile field at that time demonstrated no organisms or other sources of contamination. The second patient's surgery was delayed to discuss her case with the infectious disease team. Scant literature exists to guide recommendations. Ultimately, a single permethrin treatment immediately before surgery was recommended and followed by our team. After careful prepping and draping, a louse was observed on the sterile field near the planned pin insertion site. The case was immediately canceled and delayed indefinitely. After two additional treatments over the next 4 days, only eggs (but no active insects) were observed in the patient's hair. We elected to proceed to surgery at that time, which concluded without issue., Conclusion: The surgical implications of an active lice infestation are numerous. Administration of antiparasitic medication in the immediate pre-operative period causes increased movement in pediculosis capitis, which may increase risk of sterile field contamination. Elective procedures should be postponed to complete multiple rounds of permethrin. In cases of urgent/emergent surgery, or in which treatment delay is unfeasible, foregoing delousing treatment in the immediate pre-operative period may be recommended., Competing Interests: Conflict of Interest: Nil, (Copyright: © Indian Orthopaedic Research Group.)

Background: Riding off-road vehicles is associated with the risk of injury to the extremities. There are two main types of four-wheel recreational off-road vehicles: quads or all-terrain vehicles (ATVs), which are essentially four-wheel off-road motorcycles, and recreational off-highway vehicles (ROVs), also colloquially referred to as utility terrain vehicles, which have side-by-side seating, higher maximum speeds, and a roll cage. There are multiple orthopaedic society position statements on ATVs, but none on ROVs. Perhaps this is because the injury patterns and differences between the two vehicles have not been elucidated., Questions/purposes: (1) What patient, vehicle (ROVs versus ATVs), and injury factors are associated with amputation? (2) What are the anatomic location distributions of fractures and amputations by vehicle type?, Methods: Records of all patients in our hospital's billing system who had both a diagnostic code indicating an accident related to an off-road vehicle and one indicating an extremity or pelvic fracture between February 2014 and January 2020 were screened; this resulted in the identification of 328 patients with fractures resulting from off-road vehicle collisions. A total of 16% (51 of 328) of patients were excluded from the analysis because their injury did not involve either an ATV or an ROV; 277 patients were included in the final analysis. The following variables were collected: age at time of the injury, gender, BMI, vehicle type, Gustilo-Anderson type if applicable, amputation level if applicable, anatomic locations of injuries, ethanol level, and drug screen. ATV crashes accounted for 52% (145 of 277) of patients, and ROV crashes accounted for 48% (132 of 277). Patients from ATV crashes did not differ from those in ROV crashes in terms of mean age (24 ± 16 years versus 24 ± 13 years; p = 0.82), BMI (25 ± 7 kg/m 2 versus 26 ± 6 kg/m 2 ; p = 0.18), or gender (79% [114 of 145] men/boys versus 77% [102 of 132]; p = 0.79). Among patients who had a drug or ethanol screen, there was a higher percent of ATV riders who used marijuana (39% [19 of 49] versus 17% [7 of 42]; p = 0.04), but there were no differences in abnormal blood alcohol screen or abnormal nonmarijuana drug screen; however, these results were available in only about one-third of patients (99 of 277 for ethanol and 91 of 277 for drug screen). Statistical analysis was performed using logistic regression analysis for factors associated with amputation, with p values < 0.05 considered significant., Results: After controlling for differences in demographic factors, the stepwise increase in Gustilo-Anderson grade of open fracture (OR 9.8 [95% CI 3.6 to 27.0]; p < 0.001) and ROV vehicle type (OR 15.7 [95% CI 3.6 to 68.5]; p < 0.001) were both associated with amputation. There was no increase in the odds of amputation associated with age (OR 1.0 [95% CI 0.9 to 1.1]; p = 0.81), gender (OR 1.4 [95% CI 0.3 to 5.8]; p = 0.68), or BMI (OR 1.1 [95% CI 0.9 to 1.2]; p = 0.37). The most frequent ATV fractures occurred in the forearm and wrist (22% [45 of 203]), whereas most ROV injuries occurred through the metacarpals (41% [107 of 262] of fractures and 58% [18 of 31] of amputations)., Conclusion: ROV crashes are associated with a higher odds of amputation when compared with ATV crashes. Because most ROV injuries were in the forearm and below, this likely occurs when upper extremities are crushed and mangled under the roll cage in rollover ROV crashes. Because of this danger, we urge our orthopaedic societies to either update current ATV position statements to include ROVs or release separate statements on ROVs., Level of Evidence: Level III, prognostic study., Competing Interests: Each author certifies that there are no funding or commercial associations (consultancies, stock ownership, equity interest, patent/licensing arrangements, etc.) that might pose a conflict of interest in connection with the submitted article related to the author or any immediate family members. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research® editors and board members are on file with the publication and can be viewed on request., (Copyright © 2022 by the Association of Bone and Joint Surgeons.)

Free-choice paradigms such as two-bottle choice (2BC) are commonly used to characterize ethanol consumption and preference of rodent models used to study alcohol use disorder (AUD). However, these assays are limited by low temporal resolution that misses finer patterns of drinking behavior, including circadian drinking patterns that are known to vary with age and sex and are affected in AUD pathogenesis. Modern, cost-effective tools are becoming widely available that could elucidate these patterns, including open-source, Arduino-based home-cage sipper devices. We hypothesized that adaptation of these home-cage sipper devices would uncover distinct age- and sex-related differences in temporal drinking patterns. To test this hypothesis, we used the sipper devices in a continuous 2BC paradigm using water and ethanol (10%; v/v) for 14 days to measure drinking patterns of male and female adolescent (3-week), young adult (6-week), and mature adult (18-week) C57BL/6J mice. Daily grams of fluid consumption were manually recorded at the beginning of the dark cycle, while home-cage sipper devices continuously recorded the number of sips. Consistent with prior studies, females consumed more ethanol than males, and adolescent mice consumed the most out of any age group. Correlation analyses of manually recorded fluid consumption versus home-cage sipper activity revealed a statistically significant prediction of fluid consumption across all experimental groups. Sipper activity was able to capture subtle circadian differences between experimental groups, as well as distinct individual variation in drinking behavior among animals. Blood ethanol concentrations were significantly correlated with sipper data, suggesting that home-cage sipper devices can accurately determine individual timing of ethanol consumption. Overall, our studies show that augmenting the 2BC drinking paradigm with automated home-cage sipper devices can accurately measure ethanol consumption across sexes and age groups, revealing individual differences and temporal patterns of ethanol drinking behavior. Future studies utilizing these home-cage sipper devices will further dissect circadian patterns for age and sex relevant to the pathogenesis of AUD, as well as underlying molecular mechanisms for patterns in ethanol consumption., Highlights: Female mice consume more ethanol than males in a continuous access paradigmAdolescent male and female mice consume more ethanol than young or mature adult miceAutomated home-cage sipper devices accurately measure ethanol consumptionDevices reveal sex- and age-dependent differences in circadian drinking patternsDevices reveal distinct individual variation in circadian drinking patterns.

Objectives: Spin is a reporting bias that presents the beneficial effect of an experimental treatment as greater than what is found in the results of the study. This bias can result in patient care recommendations that are more subjective than objective. The purpose of this study is to identify the prevalence of spin in meta-analysis and systematic review abstracts regarding treatment of midshaft clavicle fractures., Methods: Electronic libraries (MEDLINE, Embase, Web of Science, Google Scholar) were systematically searched. Meta-analyses and systematic reviews regarding treatment of midshaft clavicular fractures were analyzed. The nine most severe types of spin commonly found in abstracts were used as an evaluation tool to assess the articles. Other variables analyzed include year of publication, journal impact factor, number of citations, and methodologic quality according to A Measurement Tool to Assess Systematic Reviews (AMSTAR-2)., Results: The database search resulted in 401 articles, of which 53 met inclusion criteria. After review, it was found that 52.8% (28/53) of the included articles contained spin within the abstract. Of the nine most severe types of spin found in abstracts, type 3 spin ("selective reporting of or overemphasis on efficacy outcomes or analysis favoring the beneficial effect of the experimental intervention") was found to be the most prevalent 28.3% (15/53)., Conclusion: This study demonstrated the presence of spin in the majority of meta-analyses and systematic review abstracts pertaining to midshaft clavicular fractures. Orthopedic surgeons should be aware and recognize spin as they review articles when deciding the treatment course for such injuries., Level of Evidence: Level 3. See Instructions for Authors for a complete description of levels of evidence., Competing Interests: Conflicts of Interest: Dr. Wesley P Phipatanakul is a paid consultant (presenter) for Arthrex, Inc and a Board or Committee Member for American Shoulder and Elbow Surgeons. Dr. Joseph N Liu is a Board or Committee Member for American Shoulder and Elbow Surgeons, Arthroscopy Association of North American, and the American Academy of Orthopaedic Surgeons., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Psychiatric and neurological disorders are influenced by an undetermined number of genes and molecular pathways that may differ among afflicted individuals. Functionally testing and characterizing biological systems is essential to discovering the interrelationship among candidate genes and understanding the neurobiology of behavior. Recent advancements in genetic, genomic, and behavioral approaches are revolutionizing modern neuroscience. Although these tools are often used separately for independent experiments, combining these areas of research will provide a viable avenue for multidimensional studies on the brain. Herein we will briefly review some of the available tools that have been developed for characterizing novel cellular and animal models of human disease. A major challenge will be openly sharing resources and datasets to effectively integrate seemingly disparate types of information and how these systems impact human disorders. However, as these emerging technologies continue to be developed and adopted by the scientific community, they will bring about unprecedented opportunities in our understanding of molecular neuroscience and behavior., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Baratta, Brandner, Plasil, Rice and Farris.)

Background: Patellar dislocation can lead to instability, pain, limited function, and recurrent dislocations. Medial patellofemoral ligament (MPFL) reconstruction leads to favorable patient reported outcomes, but many patients fail to return to previous activity levels. The purpose of this study is to determine how well patients do after MPFL reconstruction and to determine the most important factors for evaluation of patellar instability following MPFL reconstruction., Methods: After IRB approval, a retrospective chart review was performed on all patients who underwent MPFL reconstruction from January 2006 to January 2014 by two board-certified sports orthopaedic surgeons. Patients were then contacted to complete a follow-up questionnaire about satisfaction, functional status, pain, and patellar stability. Patients with at least one-year of follow-up data, a complete data set, and a completed questionnaire were included in the final analysis. Charts of 100 patients were reviewed and 54 patients met all criteria for inclusion in the study. Chi-square analysis, t-tests, and multivariate and univariate logistic regression models were used to estimate the effects of multiple variables on return to activity, satisfaction, and function while controlling for covariates with p<0.05 considered significant., Results: When asked about subluxation, 20% (11/54) reported recurrent patellar subluxation (without re-dislocation). Of the 11 patients who reported re-subluxation, 54% (6/11) reported being highly satisfied (rating of 9-10/10) with the outcome of their knee. Of the 54 patients, 54% (29/54) did not return to previous levels of activity, nevertheless, 31% (9/29) of these 29 patients reported being highly satisfied with the outcome of their knee., Conclusion: Patients report high levels of satisfaction even if they have recurrent instability or are unable to return to prior activity levels. Current scoring systems do not accurately depict patients' post-operative outcomes after MPFL Reconstruction. Level of Evidence: III ., (Copyright © The Iowa Orthopaedic Journal 2022.)

CACNA1 C, which codes for the Ca v 1.2 isoform of L-type Ca 2+ channels (LTCCs), is a prominent risk gene in neuropsychiatric and neurodegenerative conditions. A role forLTCCs, and Ca v 1.2 in particular, in transcription-dependent late long-term potentiation (LTP) has long been known. Here, we report that elimination of Ca v 1.2 channels in glutamatergic neurons also impairs theta burst stimulation (TBS)-induced LTP in the hippocampus, known to be transcription-independent and dependent on N-methyl D-aspartate receptors (NMDARs) and local protein synthesis at synapses. Our expansion of the established role of Ca v 1.2channels in LTP broadens understanding of synaptic plasticity and identifies a new cellular phenotype for exploring treatment strategies for cognitive dysfunction.

JC virus (JCV) can cause a lytic infection of oligodendrocytes and astrocytes in the central nervous system (CNS) leading to progressive multifocal leukoencephalopathy (PML). JCV can also infect meningeal and choroid plexus cells causing JCV meningitis (JCVM). Whether JCV also infects meningeal and choroid plexus cells in PML patients and other immunosuppressed individuals with no overt symptoms of meningitis remains unknown. We therefore analyzed archival formalin-fixed, paraffin-embedded brain samples from PML patients, and HIV-seropositive and seronegative control subjects by immunohistochemistry for the presence of JCV early regulatory T Ag and JCV VP1 late capsid protein. In meninges, we detected JCV T Ag in 11/48 (22.9%) and JCV VP1 protein in 8/48 (16.7%) PML patients. In choroid plexi, we detected JCV T Ag in 1/7 (14.2%) and JCV VP1 protein in 1/8 (12.5%) PML patients. Neither JCV T Ag nor VP1 protein could be detected in meninges or choroid plexus of HIV-seropositive and HIV-seronegative control subjects without PML. In addition, examination of underlying cerebellar cortex of PML patients revealed JCV-infected cells in the molecular layer, including GAD 67+ interneurons, but not in HIV-seropositive and HIV-seronegative control subjects without PML. Our findings suggest that productive JCV infection of meningeal cells and choroid plexus cells also occurs in PML patients without signs or symptoms of meningitis. The phenotypic characterization of JCV-infected neurons in the molecular layer deserves further study. This data provides new insight into JCV pathogenesis in the CNS.

Bridging integrator 1 (BIN1) is the most significant late-onset Alzheimer's disease (AD) susceptibility locus identified via genome-wide association studies. BIN1 is an adaptor protein that regulates membrane dynamics in the context of endocytosis and membrane remodeling. An increase in BIN1 expression and changes in the relative levels of alternatively spliced BIN1 isoforms have been reported in the brains of patients with AD. BIN1 can bind to Tau, and an increase in BIN1 expression correlates with Tau pathology. In contrast, the loss of BIN1 expression in cultured cells elevates Aβ production and Tau propagation by insfluencing endocytosis and recycling. Here, we show that BIN1 accumulates adjacent to amyloid deposits in vivo. We found an increase in insoluble BIN1 and a striking accrual of BIN1 within and near amyloid deposits in the brains of multiple transgenic models of AD. The peri-deposit aberrant BIN1 localization was conspicuously different from the accumulation of APP and BACE1 within dystrophic neurites. Although BIN1 is highly expressed in mature oligodendrocytes, BIN1 association with amyloid deposits occurred in the absence of the accretion of other oligodendrocyte or myelin proteins. Finally, super-resolution microscopy and immunogold electron microscopy analyses highlight the presence of BIN1 in proximity to amyloid fibrils at the edges of amyloid deposits. These results reveal the aberrant accumulation of BIN1 is a feature associated with AD amyloid pathology. Our findings suggest a potential role for BIN1 in extracellular Aβ deposition in vivo that is distinct from its well-characterized function as an adaptor protein in endocytosis and membrane remodeling., (© 2018 International Society of Neuropathology.)

Alzheimer's disease (AD) is pathologically characterized by the deposition of the β-amyloid (Aβ) peptide in senile plaques in the brain, leading to neuronal dysfunction and eventual decline in cognitive function. Genome-wide association studies have identified the bridging integrator 1 ( BIN1 ) gene within the second most significant susceptibility locus for late-onset AD. BIN1 is a member of the amphiphysin family of proteins and has reported roles in the generation of membrane curvature and endocytosis. Endocytic dysfunction is a pathological feature of AD, and endocytosis of the amyloid precursor protein is an important step in its subsequent cleavage by β-secretase (BACE1). In vitro evidence implicates BIN1 in endosomal sorting of BACE1 and Aβ generation in neurons, but a role for BIN1 in this process in vivo is yet to be described. Here, using biochemical and immunohistochemistry analyses we report that a 50% global reduction of BIN1 protein levels resulting from a single Bin1 allele deletion in mice does not change BACE1 levels or localization in vivo , nor does this reduction alter the production of endogenous murine Aβ in nontransgenic mice. Furthermore, we found that reduction of BIN1 levels in the 5XFAD mouse model of amyloidosis does not alter Aβ deposition nor behavioral deficits associated with cerebral amyloid burden. Finally, a conditional BIN1 knockout in excitatory neurons did not alter BACE1, APP, C-terminal fragments derived from BACE1 cleavage of APP, or endogenous Aβ levels. These results indicate that BIN1 function does not regulate Aβ generation in vivo .

A homozygous nonsense mutation in the cereblon ( CRBN ) gene results in autosomal recessive, nonsyndromic intellectual disability that is devoid of other phenotypic features, suggesting a critical role of CRBN in mediating learning and memory. In this study, we demonstrate that adult male Crbn knock-out ( Crbn KO ) mice exhibit deficits in hippocampal-dependent learning and memory tasks that are recapitulated by focal knock-out of Crbn in the adult dorsal hippocampus, with no changes in social or repetitive behavior. Cellular studies identify deficits in long-term potentiation at Schaffer collateral CA1 synapses. We further show that Crbn is robustly expressed in the mouse hippocampus and Crbn KO mice exhibit hyperphosphorylated levels of AMPKα (Thr172). Examination of processes downstream of AMP-activated protein kinase (AMPK) finds that Crbn KO mice have a selective impairment in mediators of the mTORC1 translation initiation pathway in parallel with lower protein levels of postsynaptic density glutamatergic proteins and higher levels of excitatory presynaptic markers in the hippocampus with no change in markers of the unfolded protein response or autophagy pathways. Acute pharmacological inhibition of AMPK activity in adult Crbn KO mice rescues learning and memory deficits and normalizes hippocampal mTORC1 activity and postsynaptic glutamatergic proteins without altering excitatory presynaptic markers. Thus, this study identifies that loss of Crbn results in learning, memory, and synaptic defects as a consequence of exaggerated AMPK activity, inhibition of mTORC1 signaling, and decreased glutamatergic synaptic proteins. Thus, Crbn KO mice serve as an ideal model of intellectual disability to further explore molecular mechanisms of learning and memory. SIGNIFICANCE STATEMENT Intellectual disability (ID) is one of the most common neurodevelopmental disorders. The cereblon ( CRBN ) gene has been linked to autosomal recessive, nonsyndromic ID, characterized by an intelligence quotient between 50 and 70 but devoid of other phenotypic features, making cereblon an ideal protein for the study of the fundamental aspects of learning and memory. Here, using the cereblon knock-out mouse model, we show that cereblon deficiency disrupts learning, memory, and synaptic function via AMP-activated protein kinase hyperactivity, downregulation of mTORC1, and dysregulation of excitatory synapses, with no changes in social or repetitive behaviors, consistent with findings in the human population. This establishes the cereblon knock-out mouse as a model of pure ID without the confounding behavioral phenotypes associated with other current models of ID., (Copyright © 2018 the authors 0270-6474/18/382781-16$15.00/0.)

Genetic factors significantly influence susceptibility for substance abuse and mood disorders. Rodent studies have begun to elucidate a role of Ca v 1.3 L-type Ca 2+ channels in neuropsychiatric-related behaviors, such as addictive and depressive-like behaviors. Human studies have also linked the CACNA1D gene, which codes for the Ca v 1.3 protein, with bipolar disorder. However, the neurocircuitry and the molecular mechanisms underlying the role of Ca v 1.3 in neuropsychiatric phenotypes are not well established. In the present study, we directly manipulated Ca v 1.3 channels in Ca v 1.2 dihydropyridine insensitive mutant mice and found that ventral tegmental area (VTA) Ca v 1.3 channels mediate cocaine-related and depressive-like behavior through a common nucleus accumbens (NAc) shell calcium-permeable α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (CP-AMPAR) mechanism that requires GluA1 phosphorylation at S831. Selective activation of VTA Ca v 1.3 with (±)-BayK-8644 (BayK) enhanced cocaine conditioned place preference and cocaine psychomotor activity while inducing depressive-like behavior, an effect not observed in S831A phospho-mutant mice. Infusion of the CP-AMPAR-specific blocker Naspm into the NAc shell reversed the cocaine and depressive-like phenotypes. In addition, activation of VTA Ca v 1.3 channels resulted in social behavioral deficits. In contrast to the cocaine- and depression-related phenotypes, GluA1/A2 AMPARs in the NAc core mediated social deficits, independent of S831-GluA1 phosphorylation. Using a candidate gene analysis approach, we also identified single-nucleotide polymorphisms in the CACNA1D gene associated with cocaine dependence in human subjects. Together, our findings reveal novel, overlapping mechanisms through which VTA Ca v 1.3 mediates cocaine-related, depressive-like and social phenotypes, suggesting that Ca v 1.3 may serve as a target for the treatment of neuropsychiatric symptoms.

Alzheimer's disease (AD) is a devastating neurodegenerative disorder characterized by pathological brain lesions and a decline in cognitive function. β-Amyloid peptides (Aβ), derived from proteolytic processing of amyloid precursor protein (APP), play a central role in AD pathogenesis. β-Site APP cleaving enzyme 1 (BACE1), the transmembrane aspartyl protease which initiates Aβ production, is axonally transported in neurons and accumulates in dystrophic neurites near cerebral amyloid deposits in AD. BACE1 is modified by S-palmitoylation at four juxtamembrane cysteine residues. S-palmitoylation is a dynamic posttranslational modification that is important for trafficking and function of several synaptic proteins. Here, we investigated the in vivo significance of BACE1 S-palmitoylation through the analysis of knock-in mice with cysteine-to-alanine substitution at the palmitoylated residues (4CA mice). BACE1 expression, as well as processing of APP and other neuronal substrates, was unaltered in 4CA mice despite the lack of BACE1 S-palmitoylation and reduced lipid raft association. Whereas steady-state Aβ levels were similar, synaptic activity-induced endogenous Aβ production was not observed in 4CA mice. Furthermore, we report a significant reduction of cerebral amyloid burden and BACE1 accumulation in dystrophic neurites in the absence of BACE1 S-palmitoylation in mouse models of AD amyloidosis. Studies in cultured neurons suggest that S-palmitoylation is required for dendritic spine localization and axonal targeting of BACE1. Finally, the lack of BACE1 S-palmitoylation mitigates cognitive deficits in 5XFAD mice. Using transgenic mouse models, these results demonstrate that intrinsic posttranslational S-palmitoylation of BACE1 has a significant impact on amyloid pathogenesis and the consequent cognitive decline., Competing Interests: Conflict of interest statement: D.M.H. is cofounder of C2N Diagnostics, LLC, serves on the scientific advisory board of C2N Diagnostics, and consults for Eli Lilly, AbbVie, GlaxoSmithKline, Genentech, Proclara Biosciences, and Denali., (Published under the PNAS license.)

The CACNA1C gene that encodes the L-type Ca 2+ channel (LTCC) Ca v 1.2 subunit has emerged as a candidate risk gene for multiple neuropsychiatric disorders including bipolar disorder, major depressive disorder, and schizophrenia, all marked with depression-related symptoms. Although cacna1c heterozygous (HET) mice have been previously reported to exhibit an antidepressant-like phenotype, the molecular and circuit-level dysfunction remains unknown. Here we report that viral vector-mediated deletion of cacna1c in the adult prefrontal cortex (PFC) of mice recapitulates the antidepressant-like effect observed in cacna1c HET mice using the sucrose preference test (SPT), forced swim test (FST), and tail suspension test (TST). Molecular studies identified lower levels of REDD1, a protein previously linked to depression, in the PFC of HET mice, and viral-mediated REDD1 overexpression in the PFC of these HET mice reversed the antidepressant-like effect in SPT and TST. Examination of downstream REDD1 targets found lower levels of active/phosphorylated Akt (S473) with no change in mTORC1 phosphorylation. Examination of the transcription factor FoxO3a, previously linked to depression-related behavior and shown to be regulated in other systems by Akt, revealed higher nuclear levels in the PFC of cacna1c HET mice that was further increased following REDD1-mediated reversal of the antidepressant-like phenotype. Collectively, these findings suggest that REDD1 in cacna1c HET mice may influence depression-related behavior via regulation of the FoxO3a pathway. Cacna1c HET mice thus serve as a useful mouse model to further study cacna1c-associated molecular signaling and depression-related behaviors relevant to human CACNA1C genetic variants.

Recent rodent studies have demonstrated that parental cocaine exposure can influence offspring behavior, supporting the idea that environmental insults can impact subsequent generations. However, studies on the effects of paternal cocaine exposure are limited and multiple inconsistencies exist. In the current study, we behaviorally characterize the effects of paternal cocaine exposure in a C57BL/6J intergenerational mouse model. Male sires were administered cocaine hydrochloride (20mg/kg) or saline (0.01mL/g) once a day for 75days, and bred with drug naïve females twenty-four hours after the final injection. Offspring, separated by sex, were tested in a battery of behaviors. We found that paternal cocaine exposure altered sensitivity to the rewarding and stimulant effects of psychostimulants and natural reward (sucrose) in female offspring; female cocaine-sired offspring showed blunted cocaine preference using cocaine conditioned place preference (CPP) at a low dose (5mg/kg), but displayed similar preference at a higher dose (10mg/kg) compared to saline-sired controls. Additionally, cocaine-sired female offspring exhibited higher psychomotor sensitivity to cocaine (10mg/kg) and amphetamine (2mg/kg) and consumed more sucrose. Cocaine-sired males exhibited increased psychomotor effects of cocaine and amphetamine. Male offspring also displayed an anxiety-like phenotype. No effect of paternal cocaine exposure was observed on depressive-like, learning and memory or social behavior in male or female offspring. Collectively, our findings show that paternal, chronic cocaine exposure induces intergenerational behavioral effects in male and female offspring with greatest impact on sensitivity to psychostimulants and sucrose in females., (Copyright © 2017 Elsevier B.V. All rights reserved.)

CACNA1C, encoding the Ca v 1.2 subunit of L-type Ca 2+ channels, has emerged as one of the most prominent and highly replicable susceptibility genes for several neuropsychiatric disorders. Ca v 1.2 channels play a crucial role in calcium-mediated processes involved in brain development and neuronal function. Within the CACNA1C gene, disease-associated single-nucleotide polymorphisms have been associated with impaired social and cognitive processing and altered prefrontal cortical (PFC) structure and activity. These findings suggest that aberrant Ca v 1.2 signaling may contribute to neuropsychiatric-related disease symptoms via impaired PFC function. Here, we show that mice harboring loss of cacna1c in excitatory glutamatergic neurons of the forebrain (fbKO) that we have previously reported to exhibit anxiety-like behavior, displayed a social behavioral deficit and impaired learning and memory. Furthermore, focal knockdown of cacna1c in the adult PFC recapitulated the social deficit and elevated anxiety-like behavior, but not the deficits in learning and memory. Electrophysiological and molecular studies in the PFC of cacna1c fbKO mice revealed higher E/I ratio in layer 5 pyramidal neurons and lower general protein synthesis. This was concurrent with reduced activity of mTORC1 and its downstream mRNA translation initiation factors eIF4B and 4EBP1, as well as elevated phosphorylation of eIF2α, an inhibitor of mRNA translation. Remarkably, systemic treatment with ISRIB, a small molecule inhibitor that suppresses the effects of phosphorylated eIF2α on mRNA translation, was sufficient to reverse the social deficit and elevated anxiety-like behavior in adult cacna1c fbKO mice. ISRIB additionally normalized the lower protein synthesis and higher E/I ratio in the PFC. Thus this study identifies a novel Ca v 1.2 mechanism in neuropsychiatric-related endophenotypes and a potential future therapeutic target to explore.

Extensive 3' alternative splicing of the mu opioid receptor gene OPRM1 creates multiple C-terminal splice variants. However, their behavioral relevance remains unknown. The present study generated 3 mutant mouse models with truncated C termini in 2 different mouse strains, C57BL/6J (B6) and 129/SvEv (129). One mouse truncated all C termini downstream of Oprm1 exon 3 (mE3M mice), while the other two selectively truncated C-terminal tails encoded by either exon 4 (mE4M mice) or exon 7 (mE7M mice). Studies of these mice revealed divergent roles for the C termini in morphine-induced behaviors, highlighting the importance of C-terminal variants in complex morphine actions. In mE7M-B6 mice, the exon 7-associated truncation diminished morphine tolerance and reward without altering physical dependence, whereas the exon 4-associated truncation in mE4M-B6 mice facilitated morphine tolerance and reduced morphine dependence without affecting morphine reward. mE7M-B6 mutant mice lost morphine-induced receptor desensitization in the brain stem and hypothalamus, consistent with exon 7 involvement in morphine tolerance. In cell-based studies, exon 7-associated variants shifted the bias of several mu opioids toward β-arrestin 2 over G protein activation compared with the exon 4-associated variant, suggesting an interaction of exon 7-associated C-terminal tails with β-arrestin 2 in morphine-induced desensitization and tolerance. Together, the differential effects of C-terminal truncation illustrate the pharmacological importance of OPRM1 3' alternative splicing.

The amyloid precursor protein (APP), whose mutations cause Alzheimer disease, plays an important in vivo role and facilitates transmitter release. Because the APP cytosolic region (ACR) is essential for these functions, we have characterized its brain interactome. We found that the ACR interacts with proteins that regulate the ubiquitin-proteasome system, predominantly with the E3 ubiquitin-protein ligases Stub1, which binds the NH2 terminus of the ACR, and CRL4(CRBN), which is formed by Cul4a/b, Ddb1, and Crbn, and interacts with the COOH terminus of the ACR via Crbn. APP shares essential functions with APP-like protein-2 (APLP2) but not APP-like protein-1 (APLP1). Noteworthy, APLP2, but not APLP1, interacts with Stub1 and CRL4(CRBN), pointing to a functional pathway shared only by APP and APLP2. In vitro ubiquitination/ubiquitome analysis indicates that these E3 ligases are enzymatically active and ubiquitinate the ACR residues Lys(649/650/651/676/688) Deletion of Crbn reduces ubiquitination of Lys(676) suggesting that Lys(676) is physiologically ubiquitinated by CRL4(CRBN) The ACR facilitated in vitro ubiquitination of presynaptic proteins that regulate exocytosis, suggesting a mechanism by which APP tunes transmitter release. Other dementia-related proteins, namely Tau and apoE, interact with and are ubiquitinated via the ACR in vitro This, and the evidence that CRBN and CUL4B are linked to intellectual disability, prompts us to hypothesize a pathogenic mechanism, in which APP acts as a modulator of E3 ubiquitin-protein ligase(s), shared by distinct neuronal disorders. The well described accumulation of ubiquitinated protein inclusions in neurodegenerative diseases and the link between the ubiquitin-proteasome system and neurodegeneration make this concept plausible., (© 2016 by The American Society for Biochemistry and Molecular Biology, Inc.)

Background: Genome-wide association studies have identified BIN1 within the second most significant susceptibility locus in late-onset Alzheimer's disease (AD). BIN1 undergoes complex alternative splicing to generate multiple isoforms with diverse functions in multiple cellular processes including endocytosis and membrane remodeling. An increase in BIN1 expression in AD and an interaction between BIN1 and Tau have been reported. However, disparate descriptions of BIN1 expression and localization in the brain previously reported in the literature and the lack of clarity on brain BIN1 isoforms present formidable challenges to our understanding of how genetic variants in BIN1 increase the risk for AD., Methods: In this study, we analyzed BIN1 mRNA and protein levels in human brain samples from individuals with or without AD. In addition, we characterized the BIN1 expression and isoform diversity in human and rodent tissue by immunohistochemistry and immunoblotting using a panel of BIN1 antibodies., Results: Here, we report on BIN1 isoform diversity in the human brain and document alterations in the levels of select BIN1 isoforms in individuals with AD. In addition, we report striking BIN1 localization to white matter tracts in rodent and the human brain, and document that the large majority of BIN1 is expressed in mature oligodendrocytes whereas neuronal BIN1 represents a minor fraction. This predominant non-neuronal BIN1 localization contrasts with the strict neuronal expression and presynaptic localization of the BIN1 paralog, Amphiphysin 1. We also observe upregulation of BIN1 at the onset of postnatal myelination in the brain and during differentiation of cultured oligodendrocytes. Finally, we document that the loss of BIN1 significantly correlates with the extent of demyelination in multiple sclerosis lesions., Conclusion: Our study provides new insights into the brain distribution and cellular expression of an important risk factor associated with late-onset AD. We propose that efforts to define how genetic variants in BIN1 elevate the risk for AD would behoove to consider BIN1 function in the context of its main expression in mature oligodendrocytes and the potential for a role of BIN1 in the membrane remodeling that accompanies the process of myelination.

Laparoscopic sleeve gastrectomy (LSG) has been recognized as a primary procedure for the surgical management of morbid obesity. Staple-line leaks and hemorrhage are two associated complications. Staple-line buttressing materials have been suggested to decrease these complications. When used during LSG, few published papers exist that compare the incidence of leak or hemorrhage to that of nonreinforced staple-lines. The purpose of this study was to compare the incidence of leak and hemorrhage in patients who did and did not receive reinforcement with Seamguard (W.L. Gore & Associates, Flagstaff, AZ). This is a retrospective analysis of patients undergoing LSG. All patients met National Institutes of Health criteria and each had an extensive preoperative evaluation. Data was collected from inpatient and outpatient medical records. Fifty-nine patients received reinforcement and 80 patients did not. There was no significant difference in mean body mass index, age, or gender make-up between the two groups. The overall incidence of leak was 3.60 per cent. The incidence was 3.39 per cent in patients who received reinforcement and 3.75 per cent in those who did not. This was not statistically significant. There was no incidence of staple-line hemorrhage in either group. There is no conclusive evidence that Seamguard reduces staple-line leakage or hemorrhage. Studies involving a larger number of patients are necessary before recommending staple-line reinforcement.

The downward migration through soil of seeded poliovirus type 1 and echovirus type 1 and of naturally occurring enteroviruses during infiltration of sewage effluent through rapid-infiltration basins was investigated. After 5 days of flooding, the amount of seeded poliovirus type 1 that had migrated 5 to 10 cm downward through the soil profile was found to be 11% of that remaining at the initial burial depth. The amount of echovirus type 1 determined to have moved an equal distance was at least 100-fold less. Migration of naturally occurring enteroviruses during infiltration of sewage effluent through soil could not be measured with accuracy because of the possibility of virus survival from previous applications of effluent. The rate of inactivation for seeded poliovirus 1 and echovirus 1 buried in the infiltration basins ranged between 0.04 and 0.15 log10 units per day during the time when the basins were flooded. Inactivation of these same seeded virus types and of indigenous enterovirus populations in the infiltration basins during the drying portion of the sewage application cycle ranged between 0.11 and 0.52 log10 units per day. The rate of virus inactivation was dependent upon the rate of soil moisture loss. These results indicate that drying cycles during the land application of wastewater enhance virus inactivation in the soil.

Secondary sewage effluent and renovated water from four wells at the Flushing Meadows Wastewater Renovation Project near Phoenix, Arizona, in operation since 1967, were assayed approximately every 2 months in 1974 for viruses and enteric bacteria during flooding periods. No viruses of Salmonella sp. were detected in any renovated well water samples, and the numbers of fecal coliforms, fecal streptococci, and total bacteria were decreased by about 99.9% in the renovated well waters after the wastewater was filtered through about 9 m of soil.

Secondary sewage effluent and renovated water from four wells at the Flushing Meadows Wastewater Renovation Project near Phoenix, Arizona, in operation since 1967, were assayed approximately every 2 months in 1974 for viruses during flooding periods. Viruses, regularly found in the secondary effluent, were not detected in any renovated water samples. Our results indicated that human viral pathogens do not move through soil into the groundwater, but are apparently absorbed and degraded by the soil and reduced in numbers by a factor of at least 10(4) (99.99 percent removal).