Loss of O-GlcNAc glycosylation in forebrain excitatory neurons induces neurodegeneration.

O-GlcNAc glycosylation (or O-GlcNAcylation) is a dynamic, inducible posttranslational modification found on proteins associated with neurodegenerative diseases such as α-synuclein, amyloid precursor protein, and tau. Deletion of the O-GlcNAc transferase (ogt) gene responsible for the modification causes early postnatal lethality in mice, complicating efforts to study O-GlcNAcylation in mature neurons and to understand its roles in disease. Here, we report that forebrain-specific loss of OGT in adult mice leads to progressive neurodegeneration, including widespread neuronal cell death, neuroinflammation, increased production of hyperphosphorylated tau and amyloidogenic Aß-peptides, and memory deficits. Furthermore, we show that human cortical brain tissue from Alzheimer's disease patients has significantly reduced levels of OGT protein expression compared with cortical tissue from control individuals. Together, these studies indicate that O-GlcNAcylation regulates pathways critical for the maintenance of neuronal health and suggest that dysfunctional O-GlcNAc signaling may be an important contributor to neurodegenerative diseases.

Prevalence of the metabolic syndrome in children with psoriatic disease.

Adults with psoriasis have a greater risk of developing metabolic syndrome (MetS) and cardiovascular disease (CVD), but few studies have investigated the prevalence of MetS and other risk factors for CVD in children with psoriasis. In an assessor-blinded study, 20 children ages 9-17 years with a current or previously documented history of psoriasis involving 5% or more of their body surface area or psoriatic arthritis were compared with a cohort of age- and sex-matched controls with benign nevi, warts, or acne. MetS, our primary endpoint, was defined by the presence of abnormal values in at least three of the following measures: triglycerides, high-density lipoprotein cholesterol (HDL-C), fasting blood glucose (FBG), waist circumference, and blood pressure. Secondary endpoints included high-sensitivity C-reactive protein (hs-CRP), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C). Thirty percent (6/20) of children with psoriasis met the criteria for MetS, compared with 5% (1/20) of the control group (p < 0.05). Subjects with psoriasis had higher mean FBG (91.1 mg/dL) than the control group (82.9 mg/dL) (p = 0.01). There were no statistically significant differences in the other four components of MetS, BMI, BMI percentile, hs-CRP, TC, or LDL-C. The results of this trial demonstrate that children with psoriasis have higher rates of MetS than age- and sex-matched controls. It may therefore be important to evaluate children with psoriasis for components of MetS to prevent future CVD morbidity and mortality.

Acute Multidisciplinary Management of Aneurysmal Subarachnoid Hemorrhage (aSAH).

Aneurysmal subarachnoid hemorrhage is a life-threatening, neurological emergency characterized by accumulation of blood in the subarachnoid space due to a ruptured aneurysm. Over the past several decades, improvements in the clinical management of aneurysmal subarachnoid hemorrhage have led to better patient outcomes. However, aneurysmal subarachnoid hemorrhage is still associated with high morbidity and mortality. During the acute phase of aneurysmal subarachnoid hemorrhage and prior to the definitive management of the aneurysm, numerous medical emergencies, such as elevated intracranial pressure and cerebral vasospasm, must be effectively managed to ensure the best possible neurological outcome. Early and rapid open communication between the clinical specialties caring for the aneurysmal subarachnoid hemorrhage patient is vital for rapid data collection, decision-making, and definitive treatment. In this narrative review, we aim to present the current guidelines for the multidisciplinary acute management of aneurysmal subarachnoid hemorrhage.

Dendritic cell IL-23 and IL-1 production in response to schistosome eggs induces Th17 cells in a mouse strain prone to severe immunopathology.

Infection with schistosomes results in a CD4 T cell-mediated inflammatory reaction against parasite eggs that varies greatly in magnitude both in humans as well as in mice. In the murine disease, the severe form of immunopathology correlates with high levels of IL-17. We now report that live schistosome eggs stimulate dendritic cells from high pathology-prone CBA mice to produce IL-12p40, IL-6, and TGF-beta, whereas those from low pathology-prone BL/6 mice only make TGF-beta. Moreover, egg-stimulated dendritic cells plus naive CD4 T cells from CBA mice resulted in increased levels of IL-6, IL-23, IL-1beta, as well as IL-17 and the chemokines CXCL1, CXCL2, and CCL2, whereas similarly treated BL/6 cell cocultures instead expressed higher IL-4, IL-5, IL-10, and the transcription factor Foxp3. Neutralization of IL-23 and IL-1, but not of IL-6 or IL-21, profoundly inhibited egg-induced IL-17 production in the CBA cocultures. Conversely, stimulation with schistosome eggs in the presence of exogenous IL-23 and IL-1beta induced BL/6 cells to make IL-17. These findings identify IL-23 and IL-1 as critical host factors that drive IL-17 production, and suggest that parasite recognition followed by a genetically determined innate proinflammatory response induces the development of Th17 cells and thus controls the outcome of immunopathology in schistosomiasis.

Previously Uncharacterized Vacuolar-type ATPase Binding Site Discovered from Structurally Similar Compounds with Distinct Mechanisms of Action.

Using a comprehensive chemical genetics approach, we identified a member of the lignan natural product family, HTP-013, which exhibited significant cytotoxicity across various cancer cell lines. Correlation of compound activity across a panel of reporter gene assays suggested the vacuolar-type ATPase (v-ATPase) as a potential target for this compound. Additional cellular studies and a yeast haploinsufficiency screen strongly supported this finding. Competitive photoaffinity labeling experiments demonstrated that the ATP6V0A2 subunit of the v-ATPase complex binds directly to HTP-013, and further mutagenesis library screening identified resistance-conferring mutations in ATP6V0A2. The positions of these mutations suggest the molecule binds a novel pocket within the domain of the v-ATPase complex responsible for proton translocation. While other mechanisms of v-ATPase regulation have been described, such as dissociation of the complex or inhibition by natural products including bafilomycin A1 and concanamycin, this work provides detailed insight into a distinct binding pocket within the v-ATPase complex.

CCL20 and IL22 Messenger RNA Expression After Adalimumab vs Methotrexate Treatment of Psoriasis: A Randomized Clinical Trial.

IMPORTANCE: Methotrexate is a first-line systemic agent for treating of psoriasis, although its onset of effects is slower and overall it is less effective than tumor necrosis factor blockers. OBJECTIVE: To differentiate the response of psoriatic disease to adalimumab and methotrexate sodium. DESIGN, SETTING, AND PARTICIPANTS: Single-center, randomized, assessor-blind, 2-arm clinical trial of 30 patients from the outpatient dermatology center of Tufts Medical Center, enrolled from August 18, 2009, to October 11, 2011. Patients aged 18 to 85 years with chronic plaque-type psoriasis, a minimum Physician Global Assessment score of 3 (higher scores indicate more severe disease), and a psoriatic plaque of at least 2 cm were randomized in a 1:1 fashion to receive subcutaneous adalimumab or oral methotrexate. Skin biopsy specimens obtained at baseline and weeks 1, 2, 4, and 16 were given a histologic grade by blinded assessors to evaluate treatment response. Analyses were conducted from April 16, 2013, to January 5, 2015. INTERVENTIONS: A 16-week course of subcutaneous adalimumab (40 mg every 2 weeks after a loading dose) or low-dosage oral methotrexate sodium (7.5-25 mg/wk). MAIN OUTCOMES AND MEASURES: Changes in genomic, immunohistochemical, and messenger RNA (mRNA) profiles. RESULTS: Methotrexate responders experienced significant downregulation of helper T-cell-related (T(H)1, T(H)17, and T(H)22) mRNA expression compared with methotrexate nonresponders. Comparisons among adalimumab-treated patients were limited by the number of nonresponders (n = 1). Between adalimumab and methotrexate responders, we found no significant differences in gene expression at any study point or in the expression of T-cell-related mRNA at week 16. Adalimumab responders demonstrated early downregulation of chemokine (C-C motif) ligand 20 (CCL20) mRNA (mean [SE] at week 2, -1.83 [0.52], P < .001; week 16, -3.55 [0.54], P < .001) compared with late downregulation for methotrexate responders (week 2, 0.02 [0.51], P = .96; week 16, -2.96 [0.51], P < .001). Similar differences were observed with interleukin 22 (IL22) mRNA showing early downregulation for adalimumab responders (week 2, -3.17 [1.00], P < .001; week 16, -3.58 [1.00], P < .001) compared with late downregulation for methotrexate responders (week 2, -0.44 [0.68], P = .64; week 16, -5.14 [0.68], P < .001). Analysis of variance findings for key mRNA and immunohistochemical marker expression over the study course were significant only for CCL20 (P = .03) and IL22 (P = .006) mRNA comparing adalimumab and methotrexate responders. CONCLUSIONS AND RELEVANCE: Methotrexate is an immunomodulator with effects on helper T-cell signaling in psoriasis. Similar genomic and immunohistochemical response signatures and levels of mRNA downregulation at study completion among adalimumab and methotrexate responders suggest a disease-driven instead of therapeutic-driven pathway regulation. Adalimumab and methotrexate responses are differentiated by patterns of normalization of CCL20 and IL22 mRNA expression and may explain the varied onset and degree of clinical responses by each treatment. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00932113.

Use of diagnostic testing in the emergency department for patients presenting with non-traumatic abdominal pain.

The objective of the study was to measure the utilization and diagnostic value of tests used in the Emergency Department (ED) on patients with undifferentiated non-traumatic abdominal or flank pain. Specific goals were to measure how often these tests led to changes in diagnosis or disposition, which tests were most commonly used, and which tests providers considered most helpful. We conducted a pilot single-center, prospective descriptive study, enrolling all eligible adult patients who presented to our ED with non-traumatic abdominal or flank pain during defined hours of our intake period. Based on serial provider interviews pre- and post-testing, we measured the frequency of change of most likely diagnosis and disposition, which tests were performed, and the provider-perceived value of tests. We enrolled 124 subjects with a mean age of 44 years; 27% were admitted. Testing led to a change in most likely diagnosis in 37% of subjects, and in disposition in 41%. Frequency of diagnostic test use varied from a high of 93% for CBC to 6% for a blood or urine culture. Overall, 65% of patients had at least one imaging study performed, and 39% had an abdominal/pelvic computed tomography (CT) scan. Over all subjects, providers identified the most useful tests as the CT scan (31%) and urinalysis (17%). In conclusion, among ED patients who presented with non-traumatic abdominal or flank pain to one academic center, the pre-test most likely diagnosis and disposition were changed based on the ED evaluation in over one-third of subjects. Almost all received blood tests and two-thirds received one or more imaging studies. Based on providers' subjective opinions, the most valuable tests were the abdomino/pelvic CT scan and the urinalysis.

Structural mechanism of GAF-regulated σ(54) activators from Aquifex aeolicus.

The σ subunits of bacterial RNA polymerase occur in many variant forms and confer promoter specificity to the holopolymerase. Members of the σ(54) family of σ subunits require the action of a 'transcriptional activator' protein to open the promoter and initiate transcription. The activator proteins undergo regulated assembly from inactive dimers to hexamers that are active ATPases. These contact σ(54) directly and, through ATP hydrolysis, drive a conformational change that enables promoter opening. σ(54) activators use several different kinds of regulatory domains to respond to a wide variety of intracellular signals. One common regulatory module, the GAF domain, is used by σ(54) activators to sense small-molecule ligands. The structural basis for GAF domain regulation in σ(54) activators has not previously been reported. Here, we present crystal structures of GAF regulatory domains for Aquifex aeolicus σ(54) activators NifA-like homolog (Nlh)2 and Nlh1 in three functional states-an 'open', ATPase-inactive state; a 'closed', ATPase-inactive state; and a 'closed', ligand-bound, ATPase-active state. We also present small-angle X-ray scattering data for Nlh2-linked GAF-ATPase domains in the inactive state. These GAF domain dimers regulate σ(54) activator proteins by holding the ATPase domains in an inactive dimer conformation. Ligand binding of Nlh1 dramatically remodels the GAF domain dimer interface, disrupting the contacts with the ATPase domains. This mechanism has strong parallels to the response to phosphorylation in some two-component regulated σ(54) activators. We describe a structural mechanism of GAF-mediated enzyme regulation that appears to be conserved among humans, plants, and bacteria.

The accuracy and completeness of data collected by prospective and retrospective methods.

OBJECTIVES: To describe and test a model that compares the accuracy of data gathered prospectively versus retrospectively among adult emergency department patients admitted with chest pain. METHODS: The authors developed a model of information flow from subject to medical record to the clinical study case report form, based on a literature review. To test this model, a bidirectional (prospective and retrospective) study was conducted, enrolling all eligible adult patients who were admitted with a chief complaint of chest pain. The authors interviewed patients in the emergency department to determine their chest pain history and established a prospective database; this was considered the criterion standard. Then, patient medical records were reviewed to determine the accuracy and completeness of the information available through a retrospective medical record review. RESULTS: The model described applies the concepts of reliability and validity to information passed on by the study subject, the clinician, and the medical record abstractor. This study was comprised of 104 subjects, of which 63% were men and the median age was 63 years. Subjects were uncertain of responses for 0-8% of questions and responded differently upon reinterview for subsets of questions 0-30% of the time. The sensitivity of the medical record for risk factors for coronary artery disease was 0.77 to 0.93. Among the 88 subjects (85%) who indicated that their chest pain was substernal or left chest, the medical record described this location in 44%. Timing of the chest pain was the most difficult item to accurately capture from the medical record. CONCLUSIONS: Information obtained retrospectively from the abstraction of medical records is measurably less accurate than information obtained prospectively from research subjects. For certain items, more than half of the information is not available. This loss of information is related to the data types included in the study and by the assumptions that a researcher performing a retrospective study makes about implied versus explicitly stated responses. A model of information flow that incorporates the concepts of reliability and validity can be used to measure some of the loss of information that occurs at each step along the way from subject to clinician to medical record abstractor.

Duration of symptoms and follow-up patterns of patients discharged from the emergency department after presenting with abdominal or flank pain.

BACKGROUND: Little is known about the duration of symptoms and follow-up patterns of patients seen in emergency departments for abdominal or flank pain. OBJECTIVE: We aimed to measure the duration of symptoms and follow-up rate of patients discharged home from the emergency department after presenting with non-traumatic abdominal or flank pain. METHODS: We conducted a single-centre, prospective descriptive study of adult patients who presented to our emergency department with non-traumatic abdominal or flank pain and were discharged from the emergency department. We gathered clinical data during the index emergency department visit and conducted telephone interviews of subjects 2-5 weeks later. RESULTS: We reached 63 of 90 subjects (70%). The median duration of pain was 3 days after the emergency department visit. During the follow-up period, only 41% had followed-up with their family physician or primary care provider, although an additional 21% had planned to. Persistence of symptoms was common in the 37% of subjects who did not follow-up. CONCLUSION: Of subjects discharged from the emergency department after visits for non-traumatic abdominal or flank pain, most improve within several days. Fewer than half follow-up with a family practitioner or a primary care provider. Emergency department revisits are uncommon and often for unrelated problems.