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G protein-coupled receptors (GPCRs) convert extracellular stimuli to intracellular responses that regulate numerous physiological processes. Crystallographic and biophysical advances in GPCR structural analysis have aided investigations of structure-function relationships that clarify our understanding of these dynamic receptors, but the molecular mechanisms associated with activation and signaling for individual GPCRs may be more complex than was previously appreciated. Here, we investigated the proposed water-mediated, hydrogen-bonded activation switch between the conserved NPxxY motif on transmembrane helix 7 (TMH7) and a conserved tyrosine in TMH5, which contributes to α 1B -adrenoceptor (α 1B -AR) and β 2 -AR activation. Disrupting this bond by mutagenesis stabilized the α 1B -AR and the β 2 -AR in inactive-state conformations, which displayed decreased agonist potency for stimulating downstream IP 1 and cAMP signaling, respectively. Compared to that for wild-type receptors, agonist-mediated β-arrestin recruitment was substantially reduced or abolished for all α 1B -AR and β 2 -AR inactive-state mutants. However, the inactive-state β 2 -ARs exhibited decreased agonist affinity, whereas the inactive-state α 1B -ARs had enhanced agonist affinity. Conversely, antagonist affinity was unchanged for inactive-state conformations of both α 1B -AR and β 2 -AR. Removing the influence of agonist affinity on agonist potency gave a measure of signaling efficacy, which was markedly decreased for the α 1B -AR mutants but little altered for the β 2 -AR mutants. These findings highlight the pharmacological heterogeneity of inactive-state GPCR conformations, which may facilitate the rational design of drugs that target distinct conformational states of GPCRs., (Copyright © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Background: Development of autoimmune diseases is the result of a complex interplay between hereditary and environmental factors, with multiple genes contributing to the pathogenesis in human disease and in experimental models for disease. The T-box protein 3 is a transcriptional repressor essential during early embryonic development, in the formation of bone and additional organ systems, and in tumorigenesis., Methods: With the aim to find novel genes important for autoimmune inflammation, we have performed genetic studies of collagen-induced arthritis (CIA), a mouse experimental model for rheumatoid arthritis., Results: We showed that a small genetic fragment on mouse chromosome 5, including Tbx3 and three additional protein-coding genes, is linked to severe arthritis and high titers of anti-collagen antibodies. Gene expression studies have revealed differential expression of Tbx3 in B cells, where low expression was accompanied by a higher B cell response upon B cell receptor stimulation in vitro. Furthermore, we showed that serum TBX3 levels rise concomitantly with increasing severity of CIA., Conclusions: From these results, we suggest that TBX3 is a novel factor important for the regulation of gene transcription in the immune system and that genetic polymorphisms, resulting in lower expression of Tbx3, are contributing to a more severe form of CIA and high titers of autoantibodies. We also propose TBX3 as a putative diagnostic biomarker for rheumatoid arthritis.

The Mediator complex subunit 13-like (MED13L) protein is part of the multi-protein mediator complex and plays an important role in gene transcription. Polymorphisms in the MED13L gene have been linked to congenital heart anomalies and intellectual disabilities. Despite recent evidence of indirect links of MED13L to cytokine release and inflammation, impact of genetic variations in MED13L on immune cells remains unexplored. The B10.RIII and RIIIS/J mouse strains vary in susceptibility to induced experimental autoimmune disease models. From sequencing data of the two mouse strains, we identified six polymorphisms in the coding regions of Med13L. Using congenic mice, we studied the effect of these polymorphisms on immune cell development and function along with susceptibility to collagen-induced arthritis, an animal model for rheumatoid arthritis. Combining in vivo disease data, in vitro functional data, and computational analysis of the reported non-synonymous polymorphisms, we report that genetic polymorphisms in Med13L do not affect the immune phenotype in these mice and are predicted to be non-disease associated.

Multiple sclerosis is a neuroinflammatory degenerative disease, caused by activated immune cells infiltrating the CNS. The disease etiology involves both genetic and environmental factors. The mouse genetic locus, Eae27, linked to disease development in the experimental autoimmune encephalomyelitis (EAE) model for multiple sclerosis, was studied in order to identify contributing disease susceptibility factors and potential drug targets for multiple sclerosis. Studies of an Eae27 congenic mouse strain, revealed that genetic variation within Eae27 influences EAE development. The Abl2 gene, encoding the non-receptor tyrosine kinase Arg, is located in the 4,1 megabase pair long Eae27 region. The Arg protein plays an important role in cellular regulation and is, in addition, involved in signaling through the B- and T-cell receptors, important for the autoimmune response. The presence of a single nucleotide polymorphism causing an amino acid change in a near actin-interacting domain of Arg, in addition to altered lymphocyte activation in the congenic mice upon immunization with myelin antigen, makes Abl2/Arg a candidate gene for EAE. Here we demonstrate that the non-synonymous SNP does not change Arg's binding affinity for F-actin but suggest a role for Abl kinases in CNS inflammation pathogenesis by showing that pharmacological inhibition of Abl kinases ameliorates EAE, but not experimental arthritis.

Aims and Objectives: To identify the most common serious adverse events that occurred in nursing homes and their most frequent contributing factors to the improvement of safe nursing care., Background: There is a need to improve safe nursing care in nursing homes. Residents are often frail and vulnerable with extensive needs for nursing care. A relatively minor adverse event in nursing care can cause serious injury that could have been preventable., Design: This was a retrospective study, with a total sample of data regarding adverse events (n = 173) in nursing homes, concerning nursing care reported by healthcare providers in Sweden to the Health and Social Care Inspectorate. The reports were analysed with content analysis, and the frequencies of the adverse events, and their contributing factors, were described with descriptive statistics., Results: Medication errors, falls, delayed or inappropriate intervention and missed nursing care contributed to the vast majority (89%) of the serious adverse events. A total of 693 possible contributing factors were identified. The most common contributing factors were (i) lack of competence, (ii) incomplete or lack of documentation, (iii) teamwork failure and (iv) inadequate communication., Conclusions: The contributing factors frequently interacted yet they varied between different groups of serious adverse events. The resident's safety depends on the availability of staff's competence as well as adequate documentation about the resident's condition. Lack of competence was underestimated by healthcare providers., Relevance to Clinical Practice: Registered nurses and assistant nurses need to have awareness of contributing factors to adverse events in nursing care. A holistic approach to improve patient safety in nursing homes requires competence of the staff, safe environments as well as resident's and relative's participation., (© 2017 John Wiley & Sons Ltd.)

Background: Inhibition of Abl kinases has an ameliorating effect on the rodent model for multiple sclerosis, experimental autoimmune encephalomyelitis, and arrests lymphocyte activation. The family of Abl kinases consists of the Abl1/Abl and Abl2/Arg tyrosine kinases. While the Abl kinase has been extensively studied in immune activation, roles for Arg are incompletely characterized. To investigate the role for Arg in experimental autoimmune encephalomyelitis, we studied disease development in Arg -/- mice., Methods: Arg -/- and Arg +/+ mice were generated from breeding of Arg +/- mice on the C57BL/6 background. Mice were immunized with the myelin oligodendrocyte glycoprotein (MOG)35-55 peptide and disease development recorded. Lymphocyte phenotypes of wild type Arg +/+ and Arg -/- mice were studied by in vitro stimulation assays and flow cytometry., Results: The breeding of Arg +/+ and Arg -/- mice showed skewing in the frequency of born Arg -/- mice. Loss of Arg function did not affect development of experimental autoimmune encephalomyelitis, but reduced the number of splenic B-cells in Arg -/- mice following immunization with MOG peptide., Conclusions: Development of MOG-induced experimental autoimmune encephalomyelitis is not dependent on Arg, but Arg plays a role for the number of B cells in immunized mice. This might suggest a novel role for the Arg kinase in B-cell trafficking or regulation. Furthermore, the results suggest that Arg is important for normal embryonic development.

Purpose: Myeloproliferative neoplasms (MPNs) are associated with a shortened life expectancy. We assessed causes of death in patients with MPN and matched controls using both relative risks and absolute probabilities in the presence of competing risks., Patients and Methods: From Swedish registries, we identified 9,285 patients with MPN and 35,769 matched controls. A flexible parametric model was used to estimate cause-specific hazard ratios (HRs) of death and cumulative incidence functions, each with 95% CIs., Results: In patients with MPN, the HRs of death from hematologic malignancies and infections were 92.8 (95% CI, 70.0 to 123.1) and 2.7 (95% CI, 2.4 to 3.1), respectively. In patients age 70 to 79 years at diagnosis (the largest patient group), the HRs of death from cardiovascular and cerebrovascular disease were 1.5 (95% CI, 1.4 to 1.7) and 1.5 (95% CI, 1.3 to 1.8), respectively; all were statistically significantly elevated compared with those of controls. In the same age group, no difference was observed in the 10-year probability of death resulting from cardiovascular disease in patients with MPN versus controls (16.8% v 15.2%) or cerebrovascular disease (5.6% v 5.2%). In patients age 50 to 59 years at diagnosis, the 10-year probability of death resulting from cardiovascular and cerebrovascular disease was elevated, 4.2% versus 2.1% and 1.9% versus 0.4%, respectively. Survival in patients with MPN increased over time, mainly because of decreased probabilities of dying as a result of hematologic malignancies, infections, and, in young patients, cardiovascular disease., Conclusion: Patients with MPN had an overall higher mortality rate than that of matched controls, primarily because of hematologic malignancy, infections, and vascular events in younger patients. Evidently, there is still a need for effective disease-modifying agents to improve patient outcomes., (© 2015 by American Society of Clinical Oncology.)

Background: Resveratrol (RSV) and resveratrol analogs have a potential use in prostate cancer chemoprevention due to effects on for example, cell growth, apoptosis, angiogenesis, and metastasis. However, inhibition of CYP17A1, a key enzyme in the androgen biosynthesis and a target for prostate cancer therapy, has not been explored as a possible mechanism behind the effects on prostate cancer., Methods: Human adrenocortical carcinoma cells, H295R, were treated with RSV, piceatannol (PIC), 3,5,4'-triacetylresveratrol (RSVTA), 3,5-diacetylresveratrol (RSVDA), and 3,5,4'-trimethylresveratrol (RSVTM) for 24 hr at concentrations of 1, 5, 10, 25, and 50 µM. Steroid secretion, enzyme activities, and gene expression of key steps in steroidogenesis were investigated., Results: Secretion of dihydroepiandrosterone (DHEA), testosterone, and cortisol were drastically decreased by all test compounds at concentrations that did not affect cell viability. Progesterone and aldosterone secretion were increased. This steroid secretion pattern can be explained by the demonstrated inhibition of CYP17A1 enzyme activity. The most efficient CYP17A1 inhibitors were the synthetic analogs RSVTA, RSVDA, and RSVTM. Inhibition by RSVTM was more selective on the 17,20-lyase activity than hydroxylase activity of CYP17A1. Treatment of cells with all compounds, except RSVTM, caused increased estradiol levels, which could be explained by the demonstrated inhibition of estrogen sulfate conjugation, catalyzed by SULT1E1., Conclusions: Our results on CYP17A1 inhibition of RSV and RSV analogs suggest a novel mechanism for chemoprevention of prostate cancer by resveratrol and the analogs. Especially RSVTM, which has a preferential inhibition on the 17,20-lyase activity of CYP17A1, may be a promising candidate for prostate cancer chemoprevention., (© 2014 Wiley Periodicals, Inc.)

Many tumors, including lung cancers, promote immune tolerance to escape host immune surveillance and facilitate tumor growth. Tumors utilize numerous pathways to inhibit immune responses, including the elaboration of immune-suppressive mediators such as PGE2, TGF-β, IL-10, VEGF, GM-CSF, IL-6, S100A8/A9 and SCF, which recruit and/or activate myeloid-derived suppressor cells (MDSCs). MDSCs, a subset of heterogeneous bone marrow-derived hematopoietic cells, are found in the peripheral blood of cancer patients and positively correlate to malignancy. Solid tumors contain MDSCs that maintain an immune-suppressive network in the tumor microenvironment. This review will focus on the interaction of tumors with MDSCs that lead to dysregulation of antigen presentation and T-cell activities in murine tumor models. Specific genetic signatures in lung cancer modulate the activities of MDSCs and impact tumor progression. Targeting MDSCs may have a long-term antitumor benefit and is at the forefront of anticancer therapeutic strategies.

Background: A genome-wide association study (GWAS) using metabolite concentrations as proxies for enzymatic activity, suggested that two variants: rs2014355 in the gene encoding short-chain acyl-coenzyme A dehydrogenase (ACADS) and rs11161510 in the gene encoding medium-chain acyl-coenzyme A dehydrogenase (ACADM) impair fatty acid β-oxidation. Chronic exposure to fatty acids due to an impaired β-oxidation may down-regulate the glucose-stimulated insulin release and result in an increased risk of type 2 diabetes (T2D). We aimed to investigate whether the two variants associate with altered insulin release following an oral glucose load or with T2D., Methods: The variants were genotyped using KASPar® PCR SNP genotyping system and investigated for associations with estimates of insulin release and insulin sensitivity following an oral glucose tolerance test (OGTT) in a random sample of middle-aged Danish individuals (nACADS = 4,324; nACADM = 4,337). The T2D-case-control study involved a total of ~8,300 Danish individuals (nACADS = 8,313; nACADM = 8,344)., Results: In glucose-tolerant individuals the minor C-allele of rs2014355 of ACADS associated with reduced measures of serum insulin at 30 min following an oral glucose load (per allele effect (β) = -3.8% (-6.3%;-1.3%), P = 0.003), reduced incremental area under the insulin curve (β = -3.6% (-6.3%;-0.9%), P = 0.009), reduced acute insulin response (β = -2.2% (-4.2%;0.2%), P = 0.03), and with increased insulin sensitivity ISIMatsuda (β = 2.9% (0.5%;5.2%), P = 0.02). The C-allele did not associate with two other measures of insulin sensitivity or with a derived disposition index. The C-allele was not associated with T2D in the case-control analysis (OR 1.07, 95% CI 0.96-1.18, P = 0.21). rs11161510 of ACADM did not associate with any indices of glucose-stimulated insulin release or with T2D., Conclusions: In glucose-tolerant individuals the minor C-allele of rs2014355 of ACADS was associated with reduced measures of glucose-stimulated insulin release during an OGTT, a finding which in part may be mediated through an impaired β-oxidation of fatty acids.