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OBJECTIVE: The class I major histocompatibility complex (MHC) molecule HLA-B27 exhibits a strong association with the autoimmune inflammatory arthritis disorder ankylosing spondylitis (AS) and with other related spondylarthropathies. In the absence of both a defined autoimmune response and a target autoantigen(s), the propensity of HLA-B27 to misfold has been hypothesized to be a major parameter in disease pathogenesis. We undertook this study to test the hypothesis that HLA-B27 misfolding is due to exposure of cysteine residues within the heavy chain to the oxidizing environment of the endoplasmic reticulum. METHODS: A rapid acidification and alkylation modification method was used to examine cysteine residue exposure and accessibility within AS-associated and non-AS-associated HLA-B27 subtypes. RESULTS: This novel approach to probing in vivo class I MHC structure revealed that the HLA-B27 heavy chain adopts conformations not previously described. Furthermore, amino acid residues specific to subtypes HLA-B*2706, B*2709, and B*2704 can have an impact on these novel conformations and on cysteine residue exposure. CONCLUSION: HLA-B27 can adopt novel conformations, resulting in differential accessibility of cysteine residues, which can explain the propensity to misfold. Cysteine exposure in the HLA-B27 heavy chain is also affected by residues within the 114 and 116 regions, thereby providing a potential biochemical basis for the association of HLA-B27 subtypes with AS. [ABSTRACT FROM AUTHOR]

Objective: Recombinant monoclonal therapeutic antibodies like lecanemab, which target amyloid beta in Alzheimer's disease, offer a promising approach for modifying the disease progression. Due to its relatively short half-life, lecanemab administered as a bi-monthly infusion (typically 10 mg/kg) has a relatively brief half-life. Interaction with abundant plasma proteins binder in the bloodstream can affect pharmacokinetics of drugs, including their half-life. In this study, we investigated potential plasma protein binding (PPB) interaction to lecanemab using lecanemab biosimilar., Methods: Lecanemab biosimilar used in this study was based on publicly available sequences. ELISA and western blotting were used to assess lecanemab biosimilar immunoreactivity in the fractions of human plasma obtained through size exclusion chromatography. The binding of lecanemab biosimilar to candidate plasma binders was confirmed by western blotting, ELISA, and surface plasmon resonance analysis., Results: Using a combination of equilibrium dialysis, ELISA, and western blotting in human plasma, we first describe the presence of likely PPB partners to lecanemab biosimilar and then identify fibrinogen as one of them. Utilizing surface plasmon resonance, we confirmed that lecanemab biosimilar does bind to fibrinogen, although with lower affinity than to monomeric amyloid beta., Interpretation: In the context of lecanemab therapy, these results imply that fibrinogen levels could impact the levels of free antibodies in the bloodstream and that fibrinogen might serve as a reservoir for lecanemab. More broadly, these results indicate that PPB may be an important consideration when clinically utilizing therapeutic antibodies in neurodegenerative disease., (© 2024 The Author(s). Annals of Clinical and Translational Neurology published by Wiley Periodicals LLC on behalf of American Neurological Association.)

Lanthanide ions have ideal chemical properties for catalysis, such as hard Lewis acidity, fast ligand-exchange kinetics, high coordination-number preferences and low geometric requirements for coordination. As a result, many small-molecule lanthanide catalysts have been described in the literature. Yet, despite the ability of enzymes to catalyse highly stereoselective reactions under gentle conditions, very few lanthanoenzymes have been investigated. In this work, the mononuclear binding of europium(III) and gadolinium(III) to the active site of a mutant of the model enzyme phosphotriesterase are described using X-ray crystallography at 1.78 and 1.61 Å resolution, respectively. It is also shown that despite coordinating a single non-natural metal cation, the PTE-R18 mutant is still able to maintain esterase activity., (open access.)

Cytochrome P450 (CYP) enzymes are heme-thiolate monooxygenases which catalyze the oxidation of aliphatic and aromatic C-H bonds and other reactions. The oxidation of halogens by cytochrome P450 enzymes has also been reported. Here we use CYP199A4, from the bacterium Rhodopseudomonas palustris strain HaA2, with a range of para-substituted benzoic acid ligands, which contain halogens, to assess if this enzyme can oxidize these species or if the presence of these electronegative atoms can alter the outcome of P450-catalyzed reactions. Despite binding to the enzyme, there was no detectable oxidation of any of the 4-halobenzoic acids. CYP199A4 was, however, able to efficiently catalyze the oxidation of both 4-chloromethyl- and 4-bromomethyl-benzoic acid to 4-formylbenzoic acid via hydroxylation of the α‑carbon. The 4-chloromethyl substrate bound in the enzyme active site in a similar manner to 4-ethylbenzoic acid. This places the benzylic α‑carbon hydrogens in an unfavorable position for abstraction indicating a degree of substrate mobility must be possible within the active site. CYP199A4 catalyzed oxidations of 4-(2'-haloethyl)benzoic acids yielding α-hydroxylation and desaturation metabolites. The α-hydroxylation product was the major metabolite. The desaturation pathway is significantly disfavored compared to 4-ethylbenzoic acid. This may be due to the electron-withdrawing halogen atom or a different positioning of the substrate within the active site. The latter was demonstrated by the X-ray crystal structures of CYP199A4 with these substrates. Overall, the presence of a halogen atom positioned close to the heme iron can alter the binding orientation and outcomes of enzyme-catalyzed oxidation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

We review 50 years of use of 2',3'-O-trinitrophenyl (TNP)-ATP, a fluorescently tagged ATP analog. It has been extensively used to detect binding interactions of ATP to proteins and to measure parameters of those interactions such as the dissociation constant, K d , or inhibitor dissociation constant, K i . TNP-ATP has also found use in other applications, for example, as a fluorescence marker in microscopy, as a FRET pair, or as an antagonist (e.g., of P2X receptors). However, its use in protein binding studies has limitations because the TNP moiety often enhances binding affinity, and the fluorescence changes that occur with binding can be masked or mimicked in unexpected ways. The goal of this review is to provide a clear perspective of the pros and cons of using TNP-ATP to allow for better experimental design and less ambiguous data in future experiments using TNP-ATP and other TNP nucleotides., Competing Interests: All authors declare they have no conflict of interest., (© 2021 The Author(s).)

Objective: Although evidence implicates striatal cholinergic impairment as a mechanism underlying tardive dyskinesia, trials of nonspecific cholinergic agents have been inconclusive. As a partial agonist at specific nicotinic receptor subtypes, varenicline reduces drug-induced dyskinesias in animal models suggesting promise as a treatment for tardive dyskinesia., Methods: Three schizophrenia patients with tardive dyskinesia who were smokers underwent an open trial of varenicline. After a 2-week baseline, subjects received varenicline 1 mg twice daily. Changes from baseline on the Abnormal Involuntary Movement Scale were measured after a 4-week varenicline stabilization period, and 6 weeks after the smoking quit date in one patient., Results: Varenicline had no effect on mean Abnormal Involuntary Movement Scale scores after 4 weeks. Although smoking decreased after 4 weeks on varenicline and diminished further in one patient after 10 weeks, this also appeared to have no effect on ratings of tardive dyskinesia., Conclusion: In contrast to animal models, no significant change in tardive dyskinesia occurred in response to varenicline replacement in three schizophrenia patients. Further investigations of cholinergic mechanisms in tardive dyskinesia are worthwhile as agents for specific cholinergic targets become available for treatment. In addition, treatment trials of tardive dyskinesia should control for smoking status, while patients on antipsychotics receiving nicotine replacement therapies for smoking should be studied further for changes in movement.

Purpose/background: To add to limited evidence on the Abnormal Involuntary Movement Scale (AIMS) as a measure of tardive dyskinesia (TD) in clinical practice settings, the characteristics and correlates of AIMS scores were assessed., Methods/procedures: Veterans with schizophrenia/schizoaffective, bipolar, or major depressive disorders receiving antipsychotics and at least 1 AIMS score during October 1, 2014, to September 30, 2015, were identified. Tardive dyskinesia was determined by the International Classification of Diseases, Ninth Revision, Clinical Modification, codes. Correlates of AIMS scores were examined using χ or t tests. Odds ratios and β parameters with 95% confidence intervals for categorical and continuous variables associated with AIMS scores were derived from a multivariate logistic and linear regression, respectively., Findings/results: Among 7985 veterans receiving antipsychotics, only 4706 (58.9%) had at least 1 AIMS examination. Of these, 229 (4.9%) were diagnosed with possible TD. The mean total AIMS scores and AIMS awareness/incapacitation scores were significantly higher for patients with TD (both P < 0.0001). Comparing diagnostic threshold criteria of AIMS ratings, only 17.5% to 37.1% of veterans with TD were successfully identified. Among TD patients, 21.4% had a total score of moderate-severe and 15.3% had ratings of at least mild movements in 2 or more body regions. In the regression analyses, being older, African-American, having schizophrenia/schizoaffective disorder, and receiving antipsychotics or benztropine significantly increased the severity of AIMS scores. Higher AIMS scores were not predictive of outcomes other than marital status in socioeconomic or healthcare domains., Implications/conclusions: Although the AIMS is essential for TD research, its value in clinical practice without training and oversight remains unclear. Efforts to adapt screening procedures to clinical needs may be worthwhile.

Purpose/background: To inform cost-benefit decisions for veterans, the risk of tardive dyskinesia (TD) and its impact on comorbidities and outcomes were assessed., Methods/procedures: In a retrospective study, veterans with schizophrenia/schizoaffective, and bipolar and major depressive disorders receiving antipsychotics during the period October 1, 2014, to September 30, 2015, were identified. Tardive dyskinesia was determined by International Classification of Diseases, Ninth Revision, Clinical Modification codes. Correlates of TD were examined using χ or t tests. Odds ratios (ORs) and β parameters with 95% confidence intervals (CIs) for categorical and continuous variables associated with TD were derived from a multivariate logistic and linear regression, respectively., Findings/results: Among 7985 veterans, 332 (4.2%) were diagnosed as having possible TD. The odds of having TD were higher for older veterans (OR, 1.04; 95% CI, 1.03-1.05; P < 0.0001) and veterans with schizophrenia/schizoaffective disorder (OR, 1.54; 95% CI, 1.23-1.91; P < 0.0001) or diabetes (OR, 1.64; 95% CI, 1.30-2.06; P < 0.0001). Veterans with TD received more antipsychotic prescriptions (mean ± SD, 18.4 ± 30.3 vs 13.3 ± 26.4; P = 0.003) and days of supply (233.9 ± 95.4 vs 211.4 ± 102.0; P < 0.0001). They were more likely to have received 2 or more antipsychotics (27.1% vs 19.7%, P = 0.0009) and benztropine (OR, 2.25: 95% CI 1.73-2.91; P < 0.0001). Veterans with TD had a higher Charlson Comorbidity Index score (β = 0.32; SE, 0.09; 95% CI, 0.14-0.49; P = 0.0003) and higher odds of any medical hospitalization (OR, 1.45; 95% CI, 1.07-1.95; P = 0.001)., Implications/conclusions: The diagnosis of possible TD was associated with older age, schizophrenia/schizoaffective disorder, medical comorbidity, and hospitalization. Tardive dyskinesia may be a marker for patients at risk of adverse health care outcomes and diminished quality of life.

Offshore Antarctic polynyas-large openings in the winter sea ice cover-are thought to be maintained by a rapid ventilation of deep-ocean heat through convective mixing. These rare phenomena may alter abyssal properties and circulation, yet their formation mechanisms are not well understood. Here we demonstrate that concurrent upper-ocean preconditioning and meteorological perturbations are responsible for the appearance of polynyas in the Weddell Sea region of the Southern Ocean. Autonomous profiling float observations-collected in 2016 and 2017 during the largest polynyas to form near the Maud Rise seamount since 1976-reveal that the polynyas were initiated and modulated by the passage of severe storms, and that intense heat loss drove deep overturning within them. Wind-driven upwelling of record strength weakened haline stratification in the upper ocean, thus favouring destabilization in 2016 and 2017. We show that previous Weddell polynyas probably developed under similarly anomalous conditions, which are associated with a mode of Southern Hemisphere climate variability that is predicted to strengthen as a result of anthropogenic climate change.

Socioeconomic disparities were assessed in predicting metabolic risk among veterans with serious mental illness. Veterans with schizophrenia, schizoaffective, or bipolar disorders were identified in VISN 4 facilities from 10/1/2010 to 9/30/2012. Differences between patients with and without metabolic syndrome were compared using t-tests, Chi square tests and multivariate logistic regressions. Among 10,132 veterans with mental illness, 48.8% had metabolic syndrome. Multivariate logistic regression analysis confirmed that patients with metabolic syndrome were significantly more likely to be older, male, African-American, married, and receiving disability pensions but less likely to be homeless. They were more likely to receive antipsychotics, antidepressants, or anticonvulsants. Bivariate cross-sectional analysis revealed that patients with metabolic syndrome had higher rates of coronary artery disease, cerebrovascular disease, and mortality, and that metabolic syndrome was more often associated with emergency visits and psychiatric or medical hospitalizations. Demographics, socioeconomic status and medications are independent predictors of metabolic syndrome and should be considered in broader screening of risk factors in order to provide preventive interventions for metabolic syndrome.

This review focuses on recent work that has begun to establish specific functional roles for protein conformational dynamics, specifically how the conformational landscapes that proteins can sample can evolve under laboratory based evolutionary selection. We discuss recent technical advances in computational and biophysical chemistry, which have provided us with new ways to dissect evolutionary processes. Finally, we offer some perspectives on the emerging view of conformational dynamics and evolution, and the challenges that we face in rationally engineering conformational dynamics., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Background: Recent randomized evidence has demonstrated benefit with complete revascularization during the index hospitalization for multivessel coronary artery disease ST-segment elevation myocardial infarction (STEMI) patients; however, this benefit likely depends on the risk of future major adverse cardiovascular events (MACE)., Methods: Using data from Duke University Medical Center (2003-2012), we identified those at high risk for 1-year MACE among 664 STEMI patients with conservatively managed non-infarct-related artery (non-IRA) lesions. Using multivariable logistic regression, we identified clinical and angiographic characteristics associated with MACE (death, myocardial infarction, urgent revascularization) to 1 year and developed an integer-based risk prediction model for clinical use., Results: In this cohort (median age 60 years, 30% female), the unadjusted Kaplan-Meier rates for MACE at 30 days and 1 year were 10% and 28%, respectively. Characteristics associated with MACE at 1 year included reduced left ventricular ejection fraction, hypertension, heart failure, higher-risk non-IRA vessels (left main), renal insufficiency, and greater % stenosis of non-IRA lesions. A 15-point risk score including these variables had modest discrimination (C-index 0.67) across a spectrum of subsequent risk (4%-88%) for 1-year MACE., Conclusions: There is a wide spectrum of risk following primary percutaneous coronary intervention for STEMI patients with multivessel disease. Using readily available clinical characteristics, the expected incidence of MACE by 1 year can be calculated with a simplified risk score, facilitating a tailored approach to clinical care., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Triclosan (TCS), a broad-spectrum antimicrobial, is used in commercial toothpastes with reported dental benefits. Our studies on 22 popular manual toothbrushes in the U.S. showed that common toothbrush head components can accumulate substantial amounts of TCS after brushing with TCS-formulated toothpastes (TCS-TPs). After simulated 3-month brushing with a commercial best-selling TCS-TP, over one third of the adults' toothbrushes showed a cumulative TCS uptake of 21-37.5 mg, equivalent to 7-12.5 doses of the TCS used per brushing. Similar results were observed on children's toothbrushes with small pea-size heads. Elastomer components were found to be the main contributor while both nylon bristles and elastomers could act as absorptive sinks for TCS during brushing. Studies on six different TCS-TPs containing 0.3 wt% TCS showed similar profiles of TCS accumulation. The absorbed TCS was gradually released into toothpaste slurries after switching to TCS-free alternatives. Release of TCS, which typically measured at a fraction (<75%) of the standard dose using the TCS-TPs, continued for over 2 weeks and occurred most rapidly in peroxide-containing "whitening" toothpastes, followed by alkaline and surfactant-rich toothpastes. The accumulating effect was not exclusive to TCS but was commonly observed on several chemicals identified in TCS-TPs and a range of regular toothpastes.

Introduction: Tardive dyskinesia (TD) occurs in patients receiving antipsychotic treatment with dopamine receptor antagonists. Despite the prevalence of TD and its negative impact on patients' lives, there has been a lack of approved treatments and limited evidence from controlled trials of pharmacological treatment. Areas covered: PubMed was searched for English-language papers published during 2007-2016 using terms 'tardive dyskinesia' or 'drug-induced movement disorder', and 'treatment'. Studies evaluating pharmacological agents for the treatment of TD were selected. A total of 26 studies (five meta-analyses, twelve randomized controlled trials, and nine open-label observational studies) are reviewed. Expert commentary: Treatment of TD necessitates a stepwise approach. Optimization of antipsychotic therapy should be considered before initiation of antidyskinetic therapies. Data from some recent studies indicate possible improvements in TD after switching antipsychotics or with the use of amantadine, levetiracetam, piracetam, zonisamide, propranolol, vitamin B 6 , or certain unregulated herbal medicines; although significance of these improvements is unclear and require further investigation in randomized controlled trials. By contrast, recent evidence from Phase III trials of novel vesicular monoamine transporter-2 inhibitors demonstrates they could have a significant effect on TD symptom severity and suggests these agents may have the potential to transform treatment of TD in coming years.

Objective: HLA-B27 is associated with the inflammatory spondyloarthritides (SpA), although subtypes HLA-B*27:06 and HLA-B*27:09 are not. These subtypes differ from the HLA-B*27:05 disease-associated allele primarily at residues 114 and 116 of the heavy chain, part of the F pocket of the antigen-binding groove. Dimerization of HLA-B27 during assembly has been implicated in disease onset. The purpose of this study was to investigate the factors that influence differences in dimerization between disease-associated and non-disease-associated HLA-B27 alleles., Methods: HLA-B*27:05 and mutants resembling the HLA-B*27:06 and 09 subtypes were expressed in the rat C58 T cell line, the human CEM T cell line and its calnexin-deficient variant CEM.NKR. Immunoprecipitation, pulse-chase experiments, flow cytometry, and immunoblotting were performed to study the assembly kinetics, heavy-chain dimerization, and chaperone associations., Results: By expressing HLA-B*27:05, 06-like, and 09 alleles on a restrictive rat transporter associated with antigen processing background, we demonstrate that a tyrosine expressed at p116, either alone or together with an aspartic acid residue at p114, inhibited HLA-B27 dimerization and increased the assembly rate. F-pocket residues altered the associations with chaperones of the early major histocompatibility complex class I folding pathway. Calnexin was demonstrated to participate in endoplasmic reticulum (ER) stress-mediated degradation of dimers, whereas the oxidoreductase ERp57 does not appear to influence dimerization., Conclusion: Residues within the F pocket of the peptide-binding groove, which differ between disease-associated and non-disease-associated HLA-B27 subtypes, can influence the assembly process and heavy-chain dimerization, events which have been linked to the initiation of disease pathogenesis., (© 2016, American College of Rheumatology.)

"Alcohol detox" is a common presentation to acute medical services and is usually managed via standardised guidelines and protocols. We present a case of chlordiazepoxide toxicity, requiring repeated bolus doses and subsequently 24 hours of an intravenous infusion of flumazenil in response to guideline directed management of an alcohol withdrawal state. The use of prolonged flumazenil infusions to treat benzodiazepine toxicity is infrequently described. Chlordiazepoxide is metabolised in the hepatic microsomal pathway and hepatic impairment can lead to accumulation of toxic metabolites, which may have been the explanation for toxicity in this case. In patients at risk of liver dysfunction we advise the use of benzodiazepines not requiring phase 1 oxidative metabolism, such as lorazepam or oxazepam.

Purpose: Problem drug-related behavior (PDB) among patients on chronic opioid therapy may reflect an opioid use disorder. This study assessed PDB prevalence and the relationship between PDB and ongoing prescription of opioids at a primary care clinic that implemented a multifaceted opioid management program., Methods: A chart review of patients in a chronic opioid registry assessed prevalence of different types of PDB over 2 years, and whether opioids were prescribed during the last 3 months of the 2-year study period among patients with different levels of PDB., Results: Among 233 registry patients, 84.1% exhibited PDB; 45.5% exhibited ≥3 types of PDB. At the end of 2 years, most registry patients were still prescribed opioids, though patients with ≥3 types of PDB were less likely than those without PDB to be prescribed opioids (62.3% vs. 78.4%, P = 0.016)., Conclusions: PDB was pervasive in this population of patients on chronic opioid therapy. Those with the most PDB, and thus with the greatest likelihood of opioid use disorder and its social and medical consequences, were the least likely to be prescribed opioids by the clinic after 2 years. Given the rising rates of illicit opioid use in the U.S., it is important that clinics work closely with their patients who display PDB, systematically assess them for opioid use disorder, and offer evidence-based treatment., (© Copyright 2016 by the American Board of Family Medicine.)

The development of drugs to treat psychosis is a fascinating nexus for understanding mechanisms underlying disorders of mind and movement. Although the risk of drug-induced extrapyramidal syndromes has been mitigated by the acceptance of less potent dopamine antagonists, expansive marketing and off-label use has increased the number of susceptible people who may be at risk for these neurologic effects. Clinicians need to be familiar with advances in diagnosis and management, which are reviewed herein. A better understanding of drug-induced effects on the motor circuit may improve patient safety, enhance antipsychotic effectiveness, and provide insights into mechanisms underlying antipsychotic activity in parallel brain circuits., (Published by Elsevier Inc.)

A detailed microscopic analysis of renal podocyte substructure is essential to understand and diagnose nephrotic kidney disease. Currently only time consuming electron microscopy (EM) can resolve this substructure. We used structured illumination microscopy (SIM) to examine frozen sections of renal biopsies stained with an immunofluorescence marker for podocin, a protein localized to the perimeter of the podocyte foot processes and compared them with EM in both normal and nephrotic disease biopsies. SIM images of normal glomeruli revealed curvilinear patterns of podocin densely covering capillary walls similar to podocyte foot processes seen by EM. Podocin staining of all nephrotic disease biopsies were significantly different than normal, corresponding to and better visualizing effaced foot processes seen by EM. The findings support the first potential use of SIM in the diagnosis of nephrotic disease.

We describe a case of recurrent, life-threatening, catatonic stupor, without evidence of any associated medical, toxic or mental disorder. This case provides support for the inclusion of a separate category of "unspecified catatonia" in the Diagnostic and Statistical Manual of Mental Disorders 5th edition (DSM-5) to be used to classify idiopathic cases, which appears to be consistent with Kahlbaum's concept of catatonia as a distinct disease state. But beyond the limited, cross-sectional, syndromal approach adopted in DSM-5, this case more importantly illustrates the prognostic and therapeutic significance of the longitudinal course of illness in differentiating cases of catatonia, which is better defined in the Wernicke-Kleist-Leonhard classification system. The importance of differentiating cases of catatonia is further supported by the efficacy of antipsychotics in treatment of this case, contrary to conventional guidelines.

Understanding the extent to which enzyme evolution is reversible can shed light on the fundamental relationship between protein sequence, structure, and function. Here, we perform an experimental test of evolutionary reversibility using directed evolution from a phosphotriesterase to an arylesterase, and back, and examine the underlying molecular basis. We find that wild-type phosphotriesterase function could be restored (&gt;10(4)-fold activity increase), but via an alternative set of mutations. The enzyme active site converged towards its original state, indicating evolutionary constraints imposed by catalytic requirements. We reveal that extensive epistasis prevents reversions and necessitates fixation of new mutations, leading to a functionally identical sequence. Many amino acid exchanges between the new and original enzyme are not tolerated, implying sequence incompatibility. Therefore, the evolution was phenotypically reversible but genotypically irreversible. Our study illustrates that the enzyme's adaptive landscape is highly rugged, and different functional sequences may constitute separate fitness peaks.

We report on a laser that is fully embedded within a single live cell. By harnessing natural endocytosis of the cell, we introduce a fluorescent whispering gallery mode (WGM) microresonator into the cell cytoplasm. On pumping with nanojoule light pulses, green laser emission is generated inside the cells. Our approach can be applied to different cell types, and cells with microresonators remain viable for weeks under standard conditions. The characteristics of the lasing spectrum provide each cell with a barcode-type label which enables uniquely identifying and tracking individual migrating cells. Self-sustained lasing from cells paves the way to new forms of cell tracking, intracellular sensing, and adaptive imaging.

Determining the identity of cells of the immune system usually involves destructive fixation and chemical staining, or labeling with fluorescently labeled antibodies recognising specific cell surface markers. Completely label-free identification would be a significant advantage in conditions where untouched cells are a priority. We demonstrate here the use of Wavelength Modulated Raman Spectroscopy, to achieve label-free identification of purified, unfixed and untouched populations of major immune cell subsets isolated from healthy human donors. Using this technique we have been able to distinguish between CD4(+) T lymphocytes, CD8(+) T lymphocytes and CD56(+) Natural Killer cells at specificities of up to 96%. Additionally, we have been able to distinguish between CD303(+) plasmacytoid and CD1c(+) myeloid dendritic cell subsets, the key initiator and regulatory cells of many immune responses. This demonstrates the ability to identify unperturbed cells of the immune system, and opens novel opportunities to analyse immunological systems and to develop fully label-free diagnostic technologies.

We demonstrate a miniaturized single beam fiber optical trapping probe based on a high numerical aperture graded index (GRIN) micro-objective lens. This enables optical trapping at a distance of 200μm from the probe tip. The fiber trapping probe is characterized experimentally using power spectral density analysis and an original approach based on principal component analysis for accurate particle tracking. Its use for biomedical microscopy is demonstrated through optically mediated immunological synapse formation.

Objective: HLA-B27 forms misfolded heavy chain dimers, which may predispose individuals to inflammatory arthritis by inducing endoplasmic reticulum (ER) stress and the unfolded protein response (UPR). This study was undertaken to define the role of the UPR-induced ER-associated degradation (ERAD) pathway in the disposal of HLA-B27 dimeric conformers., Methods: HeLa cell lines expressing only 2 copies of a carboxy-terminally Sv5-tagged HLA-B27 were generated. The ER stress-induced protein ER degradation-enhancing α-mannosidase-like protein 1 (EDEM1) was overexpressed by transfection, and dimer levels were monitored by immunoblotting. EDEM1, the UPR-associated transcription factor X-box binding protein 1 (XBP-1), the E3 ubiquitin ligase hydroxymethylglutaryl-coenzyme A reductase degradation 1 (HRD1), and the degradation-associated proteins derlin 1 and derlin 2 were inhibited using either short hairpin RNA or dominant-negative mutants. The UPR-associated ERAD of HLA-B27 was confirmed using ER stress-inducing pharamacologic agents in kinetic and pulse chase assays., Results: We demonstrated that UPR-induced machinery can target HLA-B27 dimers and that dimer formation can be controlled by alterations to expression levels of components of the UPR-induced ERAD pathway. HLA-B27 dimers and misfolded major histocompatibility complex class I monomeric molecules bound to EDEM1 were detected, and overexpression of EDEM1 led to inhibition of HLA-B27 dimer formation. EDEM1 inhibition resulted in up-regulation of HLA-B27 dimers, while UPR-induced ERAD of dimers was prevented in the absence of EDEM1. HLA-B27 dimer formation was also enhanced in the absence of XBP-1, HRD1, and derlins 1 and 2., Conclusion: The present findings indicate that the UPR ERAD pathway can dispose of HLA-B27 dimers, thus presenting a potential novel therapeutic target for modulation of HLA-B27-associated inflammatory disease., (Copyright © 2014 by the American College of Rheumatology.)

Exosomes are secreted by many cell types and display multiple biological functions. The ability to both rapidly detect and quantify exosomes in biological samples would assist in the screening of agents that interfere with their release, and which may therefore be of clinical relevance. Nanoparticle tracking analysis, which detects the size and concentration of exosomes, was used to monitor the inhibition of exosome secretion from MDA-MB-231 breast cancer cells expressing inhibitory RNA targeted for Rab27a, a known component of the exosome pathway. Inhibition of both Rab27a and Rab27b was observed, resulting in alterations to intracellular CD63+ compartments and the release of fewer exosomes into the culture medium, as determined by nanoparticle tracking analysis and confirmed by immunoblotting and protein quantification. These data show that nanoparticle tracking analysis can be used effectively and rapidly to monitor the disruption of exosome secretion., (Copyright © 2012 Elsevier Inc. All rights reserved.)

The canonical role of major histocompatibility complex class I (MHCI) molecules in antigen presentation involves the recognition of a short peptide of intracellular origin, bound to the upper surface of the class I molecule, by CD8(+) T lymphocytes. Assembly and loading of the MHCI is a highly regulated, chaperone-mediated process and only when the fully folded MHCI molecule is correctly loaded with peptide is it released from the endoplasmic reticulum for trafficking to the cell surface. Current models of the interactions of MHCI molecules with their cognate receptors visualize them functioning as monomeric entities. However, in recent years, new data have revealed MHCI molecules with the ability to form disulphide-linked dimeric structures, with several distinct dimer entities being elucidated. We describe here three types of MHCI dimers; HLA-B27 dimers formed predominantly through the possession of an unpaired cysteine within the peptide-binding groove; HLA-G dimers, which form through a cysteine on its external surface; and a novel population we term redox-induced dimers, which can form between cysteine residues in the cytoplasmic tail domains. The characteristics of these dimeric MHCI molecules and their role in both normal immune responses and in disease pathogenesis are reviewed in this article., (© 2012 The Authors. Immunology © 2012 Blackwell Publishing Ltd.)

Nanoparticle tracking analysis permits the determination of both the size distribution and relative concentration of microvesicles, including exosomes, in the supernatants of cultured cells and biological fluids. We have studied the release of microvesicles from the human lymphoblastoid T-cell lines Jurkat and CEM. Unstimulated, both cell lines release microvesicles in the size range 70-90 nm, which can be depleted from the supernatant by ultracentrifugation at 100 000 g, and by anti-CD45 magnetic beads, and which by immunoblotting also contain the exosome-associated proteins Alix and Tsg101. Incubation with known potentiators of exosome release, the ionophores monensin and A23187, resulted in a significant increase in microvesicle release that was both time and concentration dependent. Mass spectrometric analysis of proteins isolated from ultracentrifuged supernatants of A23187-treated cells revealed the presence of exosome-associated proteins including heat-shock protein 90, tubulin, elongation factor α1, actin and glyceraldehyde 3-phosphate dehydrogenase. Additionally, treatment of peripheral blood monocyte-derived dendritic cells with bacterial lipopolysaccharide displayed an increase in secreted microvesicles. Consequently, nanoparticle tracking analysis can be effectively applied to monitor microvesicle release from cells of the immune system., (© 2012 The Authors. Immunology © 2012 Blackwell Publishing Ltd.)

Many MHC class I molecules contain unpaired cysteine residues in their cytoplasmic tail domains, the function of which remains relatively uncharacterized. Recently, it has been shown that in the small secretory vesicles known as exosomes, fully folded MHC class I dimers can form through a disulphide bond between the cytoplasmic tail domain cysteines, induced by the low levels of glutathione in these extracellular vesicles. Here we address whether similar MHC class I dimers form in whole cells by alteration of the redox environment. Treatment of the HLA-B27-expressing Epstein-Barr virus-transformed B-cell line Jesthom, and the leukaemic T-cell line CEM transfected with HLA-B27 with the strong oxidant diamide, and the apoptosis-inducing and glutathione-depleting agents hydrogen peroxide and thimerosal, induced MHC class I dimers. Furthermore, induction of apoptosis by cross-linking FasR/CD95 on CEM cells with monoclonal antibody CH-11 also induced MHC class I dimers. As with exosomal MHC class I dimers, the formation of these structures on cells is controlled by the cysteine at position 325 in the cytoplasmic tail domain of HLA-B27. Therefore, the redox environment of cells intimately controls induction of MHC class I dimers, the formation of which may provide novel structures for recognition by the immune system., (© 2012 The Authors. Immunology © 2012 Blackwell Publishing Ltd.)

Aims: The human leukocyte antigen (HLA)-B27 is strongly associated with a group of inflammatory arthritic disorders known as the spondyloarthropathies (SpAs). The unusual biochemistry of HLA-B27 has been proposed to participate in disease development, especially the enhanced ability of HLA-B27 to form several heavy chain-dimer populations. HLA-B27 possesses three unpaired cysteine (C) residues at position 67, 308, and 325, in addition to the four conserved cysteine residues at p101, 164, 203, and 259. C67 was proposed to participate in dimer formation of recombinant HLA-B27 protein and in vivo heavy chain-dimers. However, the structurally conserved C164 was demonstrated to participate in endoplasmic reticulum (ER) resident heavy chain-dimer formation. We therefore wanted to determine whether these aggregates involve cysteines other than C164 and the basis for the difference between the observed heavy chain-dimer species., Results: We determined that C164 and C101 can form distinct dimer structures and that the heterogenous nature of heavy chain-dimer species is due to differences in both redox status and conformation. Different HLA-B27 dimer populations can be found in physiologically relevant cell types derived from HLA-B27-positive patients with inflammatory arthritis. In addition, HLA-B27 dimer formation can be correlated with cellular stress induction., Innovation: The use of both mutagenesis and manipulating cellular redox environments demonstrates that HLA-B27 dimerization requires both specific cysteine?cysteine interactions and conformations with differing redox states., Conclusion: HLA-B27 heavy chain-dimerization is a complex process and these findings provide an insight into HLA-B27 misfolding and a potential contribution to inflammatory disease development.

It is becoming clear that inflammation plays a significant role in a number of neurological and psychiatric conditions. Post mortem brain samples in Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, multiple sclerosis, schizophrenia and most recently autism spectrum condition, all exhibit neuroglial activation and inflammatory markers within the CSF. Many questions remain about the underlying molecular mechanisms. By adding the pro-inflammatory cytokine, TNF-α, to mouse brain tissue we demonstrated that the frontal lobes and temporal region, areas involved in higher functions such as memory and learning, are most susceptible to cytokine-induced inflammation via the NF-κB signalling pathway. We observed direct correlations between the volumetric increase and molecular expression indicating that therapeutic targets in these lobes may require different approaches when treating conditions with a central neuroinflammatory component.

The human leucocyte antigen HLA-B27 is strongly associated with ankylosing spondylitis, a form of seronegative inflammatory arthritis. In this study aspects related to several hypothesized mechanisms of disease pathogenesis have been investigated. Blood monocyte-derived dendritic cells (DC) from a small patient cohort of 29 patients with ankylosing spondylitis and one with reactive arthritis, were compared with DC from 34 healthy control subjects, of whom four were found to be HLA-B27 positive. The ability of HLA-B27 to form heavy-chain dimers reactive with monoclonal antibody HC10 was tested, along with the induction of endoplasmic reticulum (ER) stress, assessed by splicing xbp1 mRNA and immunoblotting of Immunoglobulin Binding Protein (BiP). Additionally, the protein expression levels of the ER resident aminopeptidase gene ERAP1 in patients with ankylosing spondylitis was also determined, following its recent identification as a novel disease-associated gene. No significant difference was noted in the global levels of HC10-reactive MHC class I dimers formed in either the patient or control DC populations. Stress on the ER, as determined by xbp1 mRNA splicing, was not detected but lower levels of BiP were observed in the DC from patients. Of further potential interest, in this patient cohort the expression of ERAP1 appeared to be higher in a number of patient DC samples when compared with controls, suggesting over-expression of ERAP1 as a mechanism promoting ankylosing spondylitic pathogenesis., (© 2011 The Authors. Immunology © 2011 Blackwell Publishing Ltd.)

Objective: We compared the response to antipsychotic treatment between patients with and without tardive dyskinesia (TD) and examined the course of TD., Method: This analysis compared 200 patients with DSM-IV-defined schizophrenia and TD and 997 patients without TD, all of whom were randomly assigned to receive one of 4 second-generation antipsychotics. The primary clinical outcome measure was time to all-cause treatment discontinuation, and the primary measure for evaluating the course of TD was change from baseline in Abnormal Involuntary Movement Scale (AIMS) score. Kaplan-Meier survival analysis and Cox proportional hazards regression models were used to compare treatment discontinuation between groups. Changes in Positive and Negative Syndrome Scale (PANSS) and neurocognitive scores were compared using mixed models and analysis of variance. Treatment differences between drugs in AIMS scores and all-cause discontinuation were examined for those with TD at baseline. Percentages of patients meeting criteria for TD postbaseline or showing changes in AIMS scores were evaluated with χ(2) tests. Data were collected from January 2001 to December 2004., Results: Time to treatment discontinuation for any cause was not significantly different between the TD and non-TD groups (χ(2)(1) = 0.11, P = .743). Changes in PANSS scores were not significantly different (F(1,974) = 0.82, P = .366), but patients with TD showed less improvement in neurocognitive scores (F(1,359) = 6.53, P = .011). Among patients with TD, there were no significant differences between drugs in the decline in AIMS scores (F(3,151) = 0.32, P = .811); 55% met criteria for TD at 2 consecutive visits postbaseline, 76% met criteria for TD at some or all postbaseline visits, 24% did not meet criteria for TD at any subsequent visit, 32% showed a ≥ 50% decrease in AIMS score, and 7% showed a ≥ 50% increase in AIMS score., Conclusions: Schizophrenia patients with and without TD were similar in time to discontinuation of treatment for any cause and improvement in psychopathology, but differed in neurocognitive response. There were no significant differences between treatments in the course of TD, with most patients showing either persistence of or fluctuation in observable symptoms., Trial Registration: clinicaltrials.gov Identifier: NCT00014001., (© Copyright 2011 Physicians Postgraduate Press, Inc.)

Drug-induced movement disorders have dramatically declined with the widespread use of second-generation antipsychotics, but remain important in clinical practice and for understanding antipsychotic pharmacology. The diagnosis and management of dystonia, parkinsonism, akathisia, catatonia, neuroleptic malignant syndrome, and tardive dyskinesia are reviewed in relation to the decreased liability of the second-generation antipsychotics contrasted with evidence from the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) Schizophrenia Trial. Data from the CATIE trial imply that advantages of second-generation antipsychotics in significantly reducing extrapyramidal side effects compared with haloperidol may be diminished when compared with modest doses of lower-potency first-generation drugs., (Published by Elsevier Inc.)

Background: Evidence on antipsychotic prescribing decisions is limited. This pilot study quantified factors considered in choosing an antipsychotic and evaluated the influence of metabolic status on treatment decisions., Methods: Prescribing decisions by 4 psychiatrists were examined based on 80 adult patients initiated on antipsychotic medication diagnosed with schizophrenia, schizoaffective disorder or bipolar disorder by DSM-IV criteria, who were admitted to an acute inpatient psychiatric program of an urban Veterans Affairs Medical Center. The primary analysis examined the association between antipsychotic treatment choice and predictions of symptom control and metabolic risk. Secondary analyses included comparison of the chosen and next best treatments in predicted symptom control and metabolic risk, the frequency of reasons cited for drug choice, and the association between treatment choice and patients' baseline metabolic parameters. Mean differences and odds-ratios (OR) with 95% confidence intervals were used to compare relationships between treatment choice, ratings of risk and metabolic data., Results: Antipsychotic choice correlated significantly with ratings of predicted symptom control (OR = .92, p = 0.02) and metabolic risk (OR = .88, p = 0.01). Mean differences between the chosen and next best drugs were significant but small in predicted symptom control (F = 2.81, df = 3, 76; p<0.05) compared with larger differences in anticipated metabolic risk (F = 14.80, df = 3, 76; p = 0.0001). Nevertheless, among 24 identified reasons influencing drug selection, anticipated metabolic risk of chosen antipsychotics was cited less often than efficacy measures. In contrast to psychiatrists' expectations of metabolic risk with selected treatments, we found that patients' actual baseline BMI, fasting glucose, blood pressure, and Framingham risk levels did not necessarily predict antipsychotic treatment choice independent of other factors., Conclusion: In the context of an acute psychiatric hospitalization, pilot data suggest that predictions of symptom control and metabolic risk correlated significantly with antipsychotic choice, but study psychiatrists were willing to assume relative degrees of metabolic risk in favor of effective symptom control. However, prescribing decisions were influenced by numerous patient and treatment factors. These findings support the potential utility of the ATCQ questionnaire in quantifying antipsychotic prescribing decisions. Further validation studies of the ATCQ questionnaire could enhance translation of research findings and application of treatment guidelines., (Published by Elsevier Inc.)

Exosomes are nanometer-sized vesicles released by a number of cell types including those of the immune system, and often contain numerous immune recognition molecules including MHC molecules. We demonstrate in this study that exosomes can display a significant proportion of their MHC class I (MHC I) content in the form of disulfide-linked MHC I dimers. These MHC I dimers can be detected after release from various cell lines, human monocyte-derived dendritic cells, and can also be found in human plasma. Exosome-associated dimers exhibit novel characteristics which include 1) being composed of folded MHC I, as detected by conformational-dependent Abs, and 2) dimers forming between two different MHC I alleles. We show that dimer formation is mediated through cysteine residues located in the cytoplasmic tail domains of many MHC I molecules, and is associated with a low level of glutathione in exosomes when compared with whole cell lysates. We propose these exosomal MHC I dimers as novel structures for recognition by immune receptors.

Introduction: Ankylosing spondylitis (AS) is a severe, chronic inflammatory arthritis, with a strong association to the human major histocompatibilty complex (MHC) class I allele human leucocyte antigen (HLA) B27. Disulfide-linked HLA-B27 heavy-chain homodimers have been implicated as novel structures involved in the aetiology of AS. We have studied the formation of HLA-B27 heavy-chain homodimers in human dendritic cells, which are key antigen-presenting cells and regulators of mammalian immune responses., Method: Both an in vitro dendritic-like cell line and monocyte-derived dendritic cells from peripheral blood were studied. The KG-1 dendritic-like cell line was transfected with HLA-B27 cDNA constructs, and the cellular distribution, intracellular assembly and ability of HLA-B27 to form heavy-chain homodimers was compared with human monocyte-derived dendritic cells after stimulation with bacterial lipopolysaccharide (LPS)., Results: Immature KG-1 cells expressing HLA-B27 display an intracellular source of MHC class I heavy-chain homodimers partially overlapping with the Golgi bodies, but not the endoplasmic reticulum, which is lost at cell maturation with phorbyl-12-myristate-13-acetate (PMA) and ionomycin. Significantly, the formation of HLA-B27 homodimers in transfected KG-1 cells is induced by maturation, with a transient induction also seen in LPS-stimulated human monocyte-derived dendritic cells expressing HLA-B27. The weak association of wildtype HLA-B*2705 with the transporter associated with antigen processing could also be enhanced by mutation of residues at position 114 and 116 in the peptide-binding groove to those present in the HLA-B*2706 allele., Conclusion: We have demonstrated that HLA-B27 heavy-chain homodimer formation can be induced by dendritic cell activation, implying that these novel structures may not be displayed to the immune system at all times. Our data suggests that the behaviour of HLA-B27 on dendritic cells may be important in the study of inflammatory arthritis.

The endoplasmic reticulum-located multimolecular peptide-loading complex functions to load optimal peptides onto major histocompatibility complex (MHC) class I molecules for presentation to CD8(+) T lymphocytes. Two oxidoreductases, ERp57 and protein-disulfide isomerase, are known to be components of the peptide-loading complex. Within the peptide-loading complex ERp57 is normally found disulfide-linked to tapasin, through one of its two thioredoxin-like redox motifs. We describe here a novel trimeric complex that disulfide links together MHC class I heavy chain, ERp57 and tapasin, and that is found in association with the transporter associated with antigen processing peptide transporter. The trimeric complex normally represents a small subset of the total ERp57-tapasin pool but can be significantly increased by altering intracellular oxidizing conditions. Direct mutation of a conserved structural cysteine residue implicates an interaction between ERp57 and the MHC class I peptide-binding groove. Taken together, our studies demonstrate for the first time that ERp57 directly interacts with MHC class I molecules within the peptide-loading complex and suggest that ERp57 and protein-disulfide isomerase act in concert to regulate the redox status of MHC class I during antigen presentation.

The oxidoreductase ERp57 is a component of the major histocompatibility complex (MHC) class I peptide-loading complex. ERp57 can interact directly with MHC class I molecules, however, little is known about which of the cysteine residues within the MHC class I molecule are relevant to this interaction. MHC class I molecules possess conserved disulfide bonds between cysteines 101-164, and 203-259 in the peptide-binding and alpha3 domain, respectively. By studying a series of mutants of these conserved residues, we demonstrate that ERp57 predominantly associates with cysteine residues in the peptide-binding domain, thus indicating ERp57 has direct access to the peptide-binding groove of MHC class I molecules during assembly.

Antipsychotic drugs are widely and increasingly prescribed for neurobehavioral disorders in elderly patients. However, the efficacy of these drugs has not been consistently demonstrated in geriatric populations and there are continuing concerns regarding adverse effects. Among the latter are severe neurological disorders, including neuroleptic malignant syndrome. Although the incidence and mortality of neuroleptic malignant syndrome may have declined with heightened awareness of this disorder and the development of newer drugs, neuroleptic malignant syndrome still occurs in association with the use of antipsychotics. To enhance patient safety and clinical vigilance among practitioners, the authors present a clinical overview of neuroleptic malignant syndrome.

Comorbid cocaine abuse adversely affects clinical outcomes in schizophrenia. Using a prospective, randomized, parallel group design (N = 24), we tested the hypothesis that patients with schizophrenia treated with olanzapine have reduced cocaine craving and abuse compared with those treated with haloperidol. In addition, we examined whether this differential effect correlated with reductions in extrapyramidal symptoms, positive and negative symptoms, and/or depression. There were no significant differences overall in proportions of positive drug screens between treatment groups; no differences in positive, negative, or depressive symptoms; and few differences between treatment conditions in extrapyramidal symptoms. However, craving for cocaine was rated significantly lower by patients treated with haloperidol compared with patients treated with olanzapine. Important study limitations include a small sample size and high attrition rates. Larger controlled studies are necessary to determine optimal antipsychotic therapy for patients with schizophrenia and comorbid cocaine abuse.

Context: Although olanzapine has been widely adopted as a treatment of choice for schizophrenia, its long-term effectiveness and costs have not been evaluated in a controlled trial in comparison with a standard antipsychotic drug., Objective: To evaluate the effectiveness and cost impact of olanzapine compared with haloperidol in the treatment of schizophrenia., Design and Setting: Double-blind, randomized controlled trial with randomization conducted between June 1998 and June 2000 at 17 US Department of Veterans Affairs medical centers., Participants: Three hundred nine patients with a Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition diagnosis of schizophrenia or schizoaffective disorder, serious symptoms, and serious dysfunction for the previous 2 years. Fifty-nine percent fully completed and 36% partially completed follow-up assessments., Interventions: Patients were randomly assigned to receive flexibly dosed olanzapine, 5 to 20 mg/d, with prophylactic benztropine, 1 to 4 mg/d (n = 159); or haloperidol, 5 to 20 mg/d (n = 150), for 12 months., Main Outcome Measures: Standardized measures of symptoms, quality of life, neurocognitive status, and adverse effects of medication. Veterans Affairs administrative data and interviews concerning non-VA service use were used to estimate costs from the perspective of the VA health care system and society as a whole (ie, consumption of all resources on behalf of these patients)., Results: There were no significant differences between groups in study retention; positive, negative, or total symptoms of schizophrenia; quality of life; or extrapyramidal symptoms. Olanzapine was associated with reduced akathisia in the intention-to-treat analysis (P<.001) and with lower symptoms of tardive dyskinesia in a secondary analysis including only observations during blinded treatment with study drug. Small but significant advantages were also observed on measures of memory and motor function. Olanzapine was also associated with more frequent reports of weight gain and significantly greater VA costs, ranging from 3000 dollars to 9000 dollars annually. Differences in societal costs were somewhat smaller and were not significant., Conclusion: Olanzapine does not demonstrate advantages compared with haloperidol (in combination with prophylactic benztropine) in compliance, symptoms, extrapyramidal symptoms, or overall quality of life, and its benefits in reducing akathisia and improving cognition must be balanced with the problems of weight gain and higher cost.

The authors review the literature relevant to the position of Psychiatry Clerkship Director (PCD) and propose standards regarding the expectations for this position. The standards address qualifications, duties, and competencies in the areas of leadership, administration, education, mentoring, and scholarship, as well as the resources of time, administrative assistance, budget, and compensation required to carry out these duties. This paper has been endorsed by the Council of the Association of Directors of Medical Student Education in Psychiatry (ADMSEP), by the American Psychiatric Association's Committee on Medical Student Education, and by the Executive Committee of the American Association of Chairmen of Departments of Psychiatry.