Ring hulls and applications

AbstractOur goal is to develop methods that enable one to select a class K of rings and then to describe all right essential overrings or all right rings of quotients of a given ring R which lie in K. Our major method of attack is to determine the existence and/or uniqueness of right ring hulls of R in K and to use these to characterize the right essential overrings of R which are in K. Some applications are: (1) a characterization of the right rings of quotients of the 2-by-2 upper triangular matrix ring over a PID which are either Baer or right extending; (2) a characterization of a continuous ring hull for a commutative ring whose singular ideal has finite uniform dimension; (3) a characterization of the right extending rings which have the 2-by-2 matrix ring over a given division ring for their maximal right ring of quotients; (4) a characterization of the intermediate right extending rings between the 2-by-2 upper triangular matrix ring and the 2-by-2 matrix ring over a large class of local right finitely Σ-extending rings; (5) a characterization of the classical right ring of quotients as a ring hull from a certain class of rings

Skills in Handling Turbuhaler, Diskus, and Pressurized Metered-Dose Inhaler in Korean Asthmatic Patients

Purpose: The objective of this study was to evaluate skills in handling inhalers and factors associated with these skills among patients with asthma who had undergone treatment at special asthma and allergy clinics in Korea. Methods: We enrolled 78 subjects who used Turbuhaler and 145 who used Diskus for asthma control at special clinics in 10 university hospitals and visually assessed their skills in handling these inhalers. We also evaluated skills in 137 subjects who had used pressurized metered-dose inhalers (pMDIs) for symptom relief. Age, sex, duration of asthma and inhaler use, smoking status, monthly income, highest grade completed in school and previous instruction for handling inhalers were also measured to evaluate their association with overall inhaler skills. Results: Performance grade was inadequate for 12.8% of participants using Turbuhaler, 6.2% for Diskus, and 23.4% for pMDIs. The success rates for each step in handling the inhalers were relatively high except for the "exhale slowly to residual volume" step, in which success rates ranged from 24.2% to 28.5%. Older age, male sex, lower educational grade, and absence of previous instruction for handling inhalers were associated with inadequate inhaler technique in univariate analysis; however, only older age and absence of previous instruction remained significant independent risk factors in multivariate analysis. Conclusions: Among Korean asthmatic patients in special asthma and allergy clinics, skills in handling their inhalers were mostly excellent; meanwhile, older age and absence of previous instruction for handling inhalers were associated with inadequate techniques

Protective Effect of Ginseng Polysaccharides on Influenza Viral Infection

Ginseng polysaccharide has been known to have multiple immunomodulatory effects. In this study, we investigated whether Panax ginseng polysaccharide (GP) would have a preventive effect on influenza infection. Administration of mice with GP prior to infection was found to confer a survival benefit against infection with H1N1 (A/PR/8/34) and H3N2 (A/Philippines/82) influenza viruses. Mice infected with the 2009 H1N1 virus suspended in GP solution showed moderately enhanced survival rates and lower levels of lung viral titers and the inflammatory cytokine (IL-6). Daily treatment of vaccinated mice with GP improved their survival against heterosubtypic lethal challenge. This study demonstrates the first evidence that GP can be used as a remedy against influenza viral infection

Pyruvate Dehydrogenase Kinase Is a Metabolic Checkpoint for Polarization of Macrophages to the M1 Phenotype

Metabolic reprogramming during macrophage polarization supports the effector functions of these cells in health and disease. Here, we demonstrate that pyruvate dehydrogenase kinase (PDK), which inhibits the pyruvate dehydrogenase-mediated conversion of cytosolic pyruvate to mitochondrial acetyl-CoA, functions as a metabolic checkpoint in M1 macrophages. Polarization was not prevented by PDK2 or PDK4 deletion but was fully prevented by the combined deletion of PDK2 and PDK4; this lack of polarization was correlated with improved mitochondrial respiration and rewiring of metabolic breaks that are characterized by increased glycolytic intermediates and reduced metabolites in the TCA cycle. Genetic deletion or pharmacological inhibition of PDK2/4 prevents polarization of macrophages to the M1 phenotype in response to inflammatory stimuli (lipopolysaccharide plus IFN-γ). Transplantation of PDK2/4-deficient bone marrow into irradiated wild-type mice to produce mice with PDK2/4-deficient myeloid cells prevented M1 polarization, reduced obesity-associated insulin resistance, and ameliorated adipose tissue inflammation. A novel, pharmacological PDK inhibitor, KPLH1130, improved high-fat diet-induced insulin resistance; this was correlated with a reduction in the levels of pro-inflammatory markers and improved mitochondrial function. These studies identify PDK2/4 as a metabolic checkpoint for M1 phenotype polarization of macrophages, which could potentially be exploited as a novel therapeutic target for obesity-associated metabolic disorders and other inflammatory conditions