138 research outputs found
Leader Election in Anonymous Rings: Franklin Goes Probabilistic
We present a probabilistic leader election algorithm for anonymous, bidirectional, asynchronous rings. It is based on an algorithm from Franklin, augmented with random identity selection, hop counters to detect identity clashes, and round numbers modulo 2. As a result, the algorithm is finite-state, so that various model checking techniques can be employed to verify its correctness, that is, eventually a unique leader is elected with probability one. We also sketch a formal correctness proof of the algorithm for rings with arbitrary size
Management Reality of Female Patients with COPD: A Multicenter Cross-Sectional CAP Study in Japan
Tasuku Yamamoto,1,2 Keiji Oishi,1 Syuichiro Ohata,1 Yoriyuki Murata,1 Yoshikazu Yamaji,1 Maki Asami-Noyama,1 Nobutaka Edakuni,1 Tomoyuki Kakugawa,3 Tsunahiko Hirano,1 Kazuto Matsunaga1 1Department of Respiratory Medicine and Infectious Disease, Graduate School of Medicine, Yamaguchi University, Ube, Yamaguchi, Japan; 2Department of Respiratory Medicine, National Hospital Organization Yamaguchi-Ube Medical Center, Ube, Yamaguchi, Japan; 3Department of Pulmonology and Gerontology, Graduate School of Medicine, Yamaguchi University, Ube, Yamaguchi, JapanCorrespondence: Keiji Oishi, Department of Respiratory Medicine and Infectious Disease, Graduate School of Medicine, Yamaguchi University, 1-1-1 Minami-kogushi, Ube, Yamaguchi, 755-8505, Japan, Tel +81 836 85 3123, Fax +81 836 85 3124, Email [email protected]: Reports from Europe and North America suggest that female chronic obstructive pulmonary disease (COPD) patients have a higher symptom burden and mortality than male patients. However, little is known about the management reality of female patients with COPD in Japan.Patients and Methods: We compared the clinical characteristics of female COPD patients with those of male using the cohort of the COPD Assessment in Practice study, which is a cross-sectional multicenter observational study.Results: Of the 1168 patients, 133 (11.4%) were female. A history of never smoking was higher in females than males (p< 0.01). Although there was no difference in age or forced expiratory volume in one second (FEV1) % predicted between the groups, modified medical research council dyspnea scale (mMRC) and number of frequent exacerbators were higher in females (mMRC≥ 2: p< 0.01; number of exacerbations≥ 2: p=0.011). The mean forced vital capacity and FEV1 values in females were lower than those in males (p< 0.0001 and p< 0.0001, respectively). Females were more likely to use long-term oxygen therapy and inhaled corticosteroids than males (p=0.016 and p< 0.01, respectively). The prevalence of the Global Initiative for Chronic Obstructive Lung Disease (GOLD) groups B, C, D (ABCD GOLD 2017 classification), and E (ABE GOLD 2023 classification) was higher in females than in males.Conclusion: The disease burden of female patients with COPD is higher than that of male patients in Japan, suggesting the importance of interventions considering female-dominant features such as lower absolute FVC and FEV1, respiratory failure, and asthma-like conditions.Keywords: chronic obstructive pulmonary disease, exacerbation, subjective symptoms, gender difference, observational stud
Expression of HSP47 in Usual Interstitial Pneumonia and Nonspecific Interstitial Pneumonia
BACKGROUND: Heat shock protein (HSP) 47, a collagen-specific molecular chaperone, is involved in the processing and/or secretion of procollagens, and its expression is increased in various fibrotic diseases. The aim of this study was to determine whether quantitative immunohistochemical evaluation of the expression levels of HSP47, type I procollagen and α-smooth muscle actin (SMA) allows the differentiation of idiopathic usual interstitial pneumonia (UIP) from UIP associated with collagen vascular disease (CVD) and idiopathic nonspecific interstitial pneumonia (NSIP). METHODS: We reviewed surgical lung biopsy specimens of 19 patients with idiopathic UIP, 7 with CVD-associated UIP and 16 with idiopathic NSIP and assigned a score for the expression of HSP47, type I procollagen and α-SMA in type II pneumocytes and/or lung fibroblasts (score 0 = no; 1 = weak; 2 = moderate; 3 = strong staining). RESULTS: The expression level of HSP47 in type II pneumocytes of idiopathic UIP was significantly higher than in CVD-associated UIP and idiopathic NSIP. The expression of HSP47 in fibroblasts was significantly higher in idiopathic UIP and idiopathic NSIP than in CVD-associated UIP. The expression of type I procollagen in type II pneumocytes was significantly higher in idiopathic UIP than in idiopathic NSIP. The expression of type I procollagen in fibroblasts was not different in the three groups, while the expression of α-SMA in fibroblasts was significantly higher in idiopathic UIP than in idiopathic NSIP. CONCLUSION: Our results suggest the existence of different fibrotic pathways among these groups involved in the expression of HSP47 and type I procollagen
Evaluation of 18F-2-deoxy-2-fluoro-glucose positron emission tomography for gastric cancer screening in asymptomatic individuals undergoing endoscopy
18F-2-deoxy-2-fluoro-glucose Positron Emission Tomography (FDG-PET) has been recently proposed as a promising cancer-screening test. However, the validity of FDG-PET in cancer screening has not been evaluated. We investigated the sensitivity of FDG-PET compared with upper gastric endoscopy in gastric cancer screening for asymptomatic individuals. A total of 2861 consecutive subjects (1600 men and 1261 women) who were asymptomatic and who underwent both FDG-PET and upper gastrointestinal endoscopy between 1 February 2004 and 31 January 2005 were included in this study. Both endoscopists and a radiologist were unaware of the results of the other diagnostic tests. The FDG-PET images were examined using criteria determined by the pattern of FDG accumulation. Sensitivity and specificity of FDG-PET were calculated compared with endoscopic diagnosis as the gold standard. Among 2861 subjects enrolled in the study, there were 20 subjects with gastric cancer, of whom 18 were T1 in depth of cancer invasion. Positive FDG-PET results were obtained only in 2 of the 20 cancer subjects. The calculated sensitivity and specificity for overall gastric cancers were 10.0% (95% confidence interval (CI): 1.2–31.7%) and 99.2% (95% CI: 98.8–99.5%), respectively. 18F-2-deoxy-2-fluoro-glucose Positron Emission Tomography was poorly sensitive for detection of gastric cancer in the early stages
Characterization of Oseltamivir-Resistant 2009 H1N1 Pandemic Influenza A Viruses
Influenza viruses resistant to antiviral drugs emerge frequently. Not surprisingly, the widespread treatment in many countries of patients infected with 2009 pandemic influenza A (H1N1) viruses with the neuraminidase (NA) inhibitors oseltamivir and zanamivir has led to the emergence of pandemic strains resistant to these drugs. Sporadic cases of pandemic influenza have been associated with mutant viruses possessing a histidine-to-tyrosine substitution at position 274 (H274Y) in the NA, a mutation known to be responsible for oseltamivir resistance. Here, we characterized in vitro and in vivo properties of two pairs of oseltaimivir-sensitive and -resistant (possessing the NA H274Y substitution) 2009 H1N1 pandemic viruses isolated in different parts of the world. An in vitro NA inhibition assay confirmed that the NA H274Y substitution confers oseltamivir resistance to 2009 H1N1 pandemic viruses. In mouse lungs, we found no significant difference in replication between oseltamivir-sensitive and -resistant viruses. In the lungs of mice treated with oseltamivir or even zanamivir, 2009 H1N1 pandemic viruses with the NA H274Y substitution replicated efficiently. Pathological analysis revealed that the pathogenicities of the oseltamivir-resistant viruses were comparable to those of their oseltamivir-sensitive counterparts in ferrets. Further, the oseltamivir-resistant viruses transmitted between ferrets as efficiently as their oseltamivir-sensitive counterparts. Collectively, these data indicate that oseltamivir-resistant 2009 H1N1 pandemic viruses with the NA H274Y substitution were comparable to their oseltamivir-sensitive counterparts in their pathogenicity and transmissibility in animal models. Our findings highlight the possibility that NA H274Y-possessing oseltamivir-resistant 2009 H1N1 pandemic viruses could supersede oseltamivir-sensitive viruses, as occurred with seasonal H1N1 viruses
Effects of doxycycline on production of growth factors and matrix metalloproteinases in pulmonary fibrosis.
Idiopathic pulmonary fibrosis (IPF) is characterized by progressive fibrosis and a poor prognosis. Alveolar epithelial cells (AECs) are considered to play important roles by releasing growth factors and matrix metalloproteinases (MMPs) and by being involved in epithelial mesenchymal transition in IPF. Doxycycline hydrochloride (DOXY), an inhibitor of MMPs, attenuates pulmonary fibrosis in models and in patients with IPF; however, the mechanism of this action remains obscure
In Vitro Effects of Pirfenidone on Cardiac Fibroblasts: Proliferation, Myofibroblast Differentiation, Migration and Cytokine Secretion
Cardiac fibroblasts (CFs) are the primary cell type responsible for cardiac fibrosis during pathological myocardial remodeling. Several studies have illustrated that pirfenidone (5-methyl-1-phenyl-2-[1H]-pyridone) attenuates cardiac fibrosis in different animal models. However, the effects of pirfenidone on cardiac fibroblast behavior have not been examined. In this study, we investigated whether pirfenidone directly modulates cardiac fibroblast behavior that is important in myocardial remodeling such as proliferation, myofibroblast differentiation, migration and cytokine secretion. Fibroblasts were isolated from neonatal rat hearts and bioassays were performed to determine the effects of pirfenidone on fibroblast function. We demonstrated that treatment of CFs with pirfenidone resulted in decreased proliferation, and attenuated fibroblast α-smooth muscle actin expression and collagen contractility. Boyden chamber assay illustrated that pirfenidone inhibited fibroblast migration ability, probably by decreasing the ratio of matrix metalloproteinase-9 to tissue inhibitor of metalloproteinase-1. Furthermore, pirfenidone attenuated the synthesis and secretion of transforming growth factor-β1 but elevated that of interleukin-10. These direct and pleiotropic effects of pirfenidone on cardiac fibroblasts point to its potential use in the treatment of adverse myocardial remodeling
- …