Algebraic charge liquids

High temperature superconductivity emerges in the cuprate compounds upon changing the electron density of an insulator in which the electron spins are antiferromagnetically ordered. A key characteristic of the superconductor is that electrons can be extracted from them at zero energy only if their momenta take one of four specific values (the `nodal points'). A central enigma has been the evolution of the zero energy electrons in the metallic state between the antiferromagnet and the superconductor, and recent experiments yield apparently contradictory results. The oscillation of the resistance in this metal as a function of magnetic field indicate that the zero energy electrons carry momenta which lie on elliptical `Fermi pockets', while ejection of electrons by high intensity light indicates that the zero energy electrons have momenta only along arc-like regions. We present a theory of new states of matter, which we call `algebraic charge liquids', which arise naturally between the antiferromagnet and the superconductor, and reconcile these observations. Our theory also explains a puzzling dependence of the density of superconducting electrons on the total electron density, and makes a number of unique predictions for future experiments.Comment: 6+8 pages, 2 figures; (v2) Rewritten for broader accessibility; (v3) corrected numerical error in Eq. (5

Distinct Properties of Hexameric but Functionally Conserved Mycobacterium tuberculosis Transcription-Repair Coupling Factor

Transcription coupled nucleotide excision repair (TC-NER) is involved in correcting UV-induced damage and other road-blocks encountered in the transcribed strand. Mutation frequency decline (Mfd) is a transcription repair coupling factor, involved in repair of template strand during transcription. Mfd from M. tuberculosis (MtbMfd) is 1234 amino-acids long harboring characteristic modules for different activities. Mtbmfd complemented Escherichia coli mfd (Ecomfd) deficient strain, enhanced survival of UV irradiated cells and increased the road-block repression in vivo. The protein exhibited ATPase activity, which was stimulated ∼1.5-fold in the presence of DNA. While the C-terminal domain (CTD) comprising amino acids 630 to 1234 showed ∼2-fold elevated ATPase activity than MtbMfd, the N-terminal domain (NTD) containing the first 433 amino acid residues was able to bind ATP but deficient in hydrolysis. Overexpression of NTD of MtbMfd led to growth defect and hypersensitivity to UV light. Deletion of 184 amino acids from the C-terminal end of MtbMfd (MfdΔC) increased the ATPase activity by ∼10-fold and correspondingly exhibited efficient translocation along DNA as compared to the MtbMfd and CTD. Surprisingly, MtbMfd was found to be distributed in monomer and hexamer forms both in vivo and in vitro and the monomer showed increased susceptibility to proteases compared to the hexamer. MfdΔC, on the other hand, was predominantly monomeric in solution implicating the extreme C-terminal region in oligomerization of the protein. Thus, although the MtbMfd resembles EcoMfd in many of its reaction characteristics, some of its hitherto unknown distinct properties hint at its species specific role in mycobacteria during transcription-coupled repair

"Closing-in" phenomenon in Alzheimer's disease and subcortical vascular dementia

BACKGROUND: The 'closing-in' phenomenon is defined as a tendency to close in on a model while copying it. This is one of several constructional apraxia observed in dementia, particularly in Alzheimer's disease (AD). The aim of this study was to investigate the usefulness of it in the differential diagnosis of AD and subcortical vascular dementia (SVD) and to clarify the factors associated with it. METHODS: We operationally defined and classified it into three types, namely overlap, adherent, and near type. We analyzed the incidence of it in patients with AD (n = 98) and SVD (n = 48). RESULTS: AD patients exhibited a significantly higher occurrence of it as compared to SVD patients. Among the different types of it, the overlap and adherent types occurred almost exclusively in AD patients. A discriminant analysis in AD subjects revealed that the scores obtained from the MMSE, CDR, Barthel index, and the Rey-Osterrieth complex figure test were correlated significantly with the occurrence of it. There was no statistical difference between the Q-EEG parameters of patients that exhibited the closing-in phenomenon and those that did not. CONCLUSIONS: This study suggests that the closing-in phenomenon is phase- and AD-specific and might be a useful tool for the differential diagnosis of AD and SVD

Prognostic Biomarkers for Esophageal Adenocarcinoma Identified by Analysis of Tumor Transcriptome

Despite many attempts to establish pre-treatment prognostic markers to understand the clinical biology of esophageal adenocarcinoma (EAC), validated clinical biomarkers or parameters remain elusive. We generated and analyzed tumor transcriptome to develop a practical biomarker prognostic signature in EAC.Untreated esophageal endoscopic biopsy specimens were obtained from 64 patients undergoing surgery and chemoradiation. Using DNA microarray technology, genome-wide gene expression profiling was performed on 75 untreated cancer specimens from 64 EAC patients. By applying various statistical and informatical methods to gene expression data, we discovered distinct subgroups of EAC with differences in overall gene expression patterns and identified potential biomarkers significantly associated with prognosis. The candidate marker genes were further explored in formalin-fixed, paraffin-embedded tissues from an independent cohort (52 patients) using quantitative RT-PCR to measure gene expression. We identified two genes whose expression was associated with overall survival in 52 EAC patients and the combined 2-gene expression signature was independently associated with poor outcome (P<0.024) in the multivariate Cox hazard regression analysis.Our findings suggest that the molecular gene expression signatures are associated with prognosis of EAC patients and can be assessed prior to any therapy. This signature could provide important improvement for the management of EAC patients

An Exploratory Study of Primary Care Physician Decision Making Regarding Total Joint Arthroplasty

BACKGROUND: For patients to experience the benefits of total joint arthroplasty (TJA), primary care physicians (PCPs) ought to know when to refer a patient for TJA and/or optimize nonsurgical treatment options for osteoarthritis (OA). OBJECTIVE: To evaluate the ability of physicians to make clinical treatment decisions. DESIGN AND PARTICIPANTS: A survey, using ten clinical vignettes, of PCPs in Indiana. MEASUREMENTS: A test score (range 0 to 10) was computed based on the number of correct answers consistent with published explicit appropriateness criteria for TJA. We also collected demographic characteristics and physicians’ perceived success rate of TJA in terms of pain relief and functional improvement. RESULTS: There were 149 PCPs (response rate = 61%) who participated. The mean test score was 6.5 ± 1.5. Only 17% correctly identified the published success rate of TJA (i.e., ≥90%). In multivariate analysis, the only physician-related variables associated with test score were ethnicity, board status, and perceived success rate of TJA. Physicians who were white (P = .001), board-certified (P = .04), and perceived a higher success rate of TJA (P = .004) had higher test scores. CONCLUSIONS: PCP knowledge with respect to guideline-concordant care for OA could be improved, specifically in deciding when to consider TJA versus optimizing nonsurgical options. Moreover, the perception of the success rate of TJA may influence a clinician’s decision making

Carbonic anhydrase 9 is a predictive marker of survival benefit from lower dose of bevacizumab in patients with previously treated metastatic colorectal cancer

<p>Abstract</p> <p>Background</p> <p>Carbonic anhydrase 9 (CA9) is a marker for hypoxia and acidosis, which is linked to a poor prognosis in human tumors. The purpose of this comparative analysis was to evaluate whether CA9 and VEGF expression are associated with survival outcomes in patients with metastatic colorectal cancer (mCRC) after treatment with bevacizumab as second or later line treatment.</p> <p>Methods</p> <p>Thirty-one mCRC patients who were treated with bevacizumab-containing chemotherapy as second or later line treatment and who had analyzable tumor paraffin blocks were selected for this study. The planned dose of bevacizumab was 5 mg/kg/2-week. Immunohistochemical (IHC) staining of CA9 and VEGF was performed and their expression was scored by the intensity multiplied by percentage of stained area.</p> <p>Results</p> <p>The overall response rate was 19.4% and the disease control rate (DCR) was 61.3% with 6 partial responses and 13 cases of stable disease. The DCR was significantly higher in patients with a lower CA9 expression score compared to those with a higher score (80.0% vs. 27.3%, respectively, P = 0.004). The patients with a low CA9 expression score also showed better outcomes with regard to the median progression-free survival (P = 0.028) and overall survival (P = 0.026). However, VEGF expression was not associated with the DCR and survival.</p> <p>Conclusion</p> <p>Lower degree of CA9 expression was associated with better clinical outcomes in patients with mCRC treated with lower dose bevacizumab-based chemotherapy. Prospective studies are now needed to determine the correlation between CA9 expression and clinical outcomes after bevacizumab treatment, at different doses and in varied settings.</p

Clinical outcomes and prognostic factors in patients with breast diffuse large B cell lymphoma; Consortium for Improving Survival of Lymphoma (CISL) study

<p>Abstract</p> <p>Background</p> <p>The breast is a rare extranodal site of non-Hodgkin lymphoma, and primary breast lymphoma (PBL) has been arbitrarily defined as disease localized to one or both breasts with or without regional lymph nodes involvement. The aim of this study was to evaluate the clinical outcomes in patients with diffuse large B cell lymphoma (DLBCL) and breast involvement, and to find the criteria of PBL reflecting the outcome and prognosis.</p> <p>Methods</p> <p>We retrospectively analyzed data from 68 patients, newly diagnosed with DLBCL and breast involvement at 16 Korean institutions between January 1994 and June 2009.</p> <p>Results</p> <p>Median age at diagnosis was 48 years (range, 20-83 years). Forty-three (63.2%) patients were PBL according to previous arbitrary criteria, sixteen (23.5%) patients were high-intermediate to high risk of international prognostic index. The patients with one extranodal disease in the breast (OED) with or without nodal disease were 49 (72.1%), and those with multiple extranodal disease (MED) were 19 (27.9%). During median follow-up of 41.5 months (range, 2.4-186.0 months), estimated 5-year progression-free survival (PFS) was 53.7 ± 7.6%, and overall survival (OS) was 60.3 ± 7.2%. The 5-year PFS and OS was significantly higher for patients with the OED group than those with the MED group (5-year PFS, 64.9 ± 8.9% vs. 27.5 ± 11.4%, p = 0.001; 5-year OS, 74.3 ± 7.6% vs. 24.5 ± 13.0%, p < 0.001). In multivariate analysis, MED (hazard ratio [HR], 3.61; 95% confidence interval [CI], 1.07-12.2) and fewer than four cycles of systemic chemotherapy with or without local treatments (HR, 4.47; 95% CI, 1.54-12.96) were independent prognostic factors for worse OS. Twenty-five (36.8%) patients experienced progression, and the cumulative incidence of progression in multiple extranodal sites or other than breasts and central nervous system was significantly different between the OED group and the MED group (5-year cumulative incidence, 9.7 ± 5.4% vs. 49.0 ± 15.1%, p = 0.001).</p> <p>Conclusions</p> <p>Our results show that the patients included in OED group, reflecting different treatment outcome, prognosis and pattern of progression, should be considered as PBL in the future trial. Further studies are warranted to validate our suggested criteria.</p

Survival in amoeba: a major selection pressure on the presence of bacterial copper and zinc resistance determinants?: identification of a "copper pathogenicity island"

The presence of metal resistance determinants in bacteria usually is attributed to geological or anthropogenic metal contamination in different environments or associated with the use of antimicrobial metals in human healthcare or in agriculture. While this is certainly true, we hypothesize that protozoan predation and macrophage killing are also responsible for selection of copper/zinc resistance genes in bacteria. In this review, we outline evidence supporting this hypothesis, as well as highlight the correlation between metal resistance and pathogenicity in bacteria. In addition, we introduce and characterize the "copper pathogenicity island" identified in Escherichia coli and Salmonella strains isolated from copper- and zinc-fed Danish pigs

Antimalarial drug artemether inhibits neuroinflammation in BV2 microglia through Nrf2-dependent mechanisms

Artemether, a lipid-soluble derivative of artemisinin has been reported to possess anti-inflammatory properties. In this study, we have investigated the molecular mechanisms involved in the inhibition of neuroinflammation by the drug. The effects of artemether on neuroinflammation-mediated HT22 neuronal toxicity were also investigated in a BV2 microglia/HT22 neuron co-culture. To investigate effects on neuroinflammation, we used LPS-stimulated BV2 microglia treated with artemether (5-40µM) for 24 hours. ELISAs and western blotting were used to detect pro inflammatory cytokines, nitric oxide, PGE2, iNOS, COX-2 and mPGES-1. BACE-1 activity and Aβ levels were measured with ELISA kits. Protein levels of targets in NF-kappaB and p38 MAPK signalling, as well as HO-1, NQO1 and Nrf2 were also measured with western blot. NF-kappaB binding to the DNA was investigated using EMSA. MTT, DNA fragmentation and ROS assays in BV2-HT22 neuronal co-culture were used to evaluate the effects of artemether on neuroinflammation-induced neuronal death. The role of Nrf2 in the anti-inflammatory activity of artemether was investigated in BV2 cells transfected with Nrf2 siRNA. Artemether significantly suppressed pro-inflammatory mediators (NO/iNOS, PGE2/COX-2/mPGES-1, TNFα, and IL-6), Aβ and BACE-1 in BV2 cells following LPS stimulation. These effects of artemether were shown to be mediated through inhibition of NF-kappaB and p38MAPK signalling. Artemether produced increased levels of HO-1, NQO1 and GSH in BV2 microglia. The drug activated Nrf2 activity by increasing nuclear translocation of Nrf2 and its binding to antioxidant response elements in BV2 cells. Transfection of BV2 microglia with Nrf2 siRNA resulted in the loss of both anti-inflammatory and neuroprotective activities of artemether. We conclude that artemether induces Nrf2 expression and suggest that Nrf2 mediates the anti-inflammatory effect of artemether in BV2 microglia. Our results suggest that this drug has a therapeutic potential in neurodegenerative disorders

Robust Reproducible Resting State Networks in the Awake Rodent Brain

Resting state networks (RSNs) have been studied extensively with functional MRI in humans in health and disease to reflect brain function in the un-stimulated state as well as reveal how the brain is altered with disease. Rodent models of disease have been used comprehensively to understand the biology of the disease as well as in the development of new therapies. RSN reported studies in rodents, however, are few, and most studies are performed with anesthetized rodents that might alter networks and differ from their non-anesthetized state. Acquiring RSN data in the awake rodent avoids the issues of anesthesia effects on brain function. Using high field fMRI we determined RSNs in awake rats using an independent component analysis (ICA) approach, however, ICA analysis can produce a large number of components, some with biological relevance (networks). We further have applied a novel method to determine networks that are robust and reproducible among all the components found with ICA. This analysis indicates that 7 networks are robust and reproducible in the rat and their putative role is discussed