Cigarette smoke-induced skeletal muscle atrophy is associated with up-regulation of USP-19 via p38 and ERK MAPKs.

Ubiquitin-specific proteases (USPs) deubiquitinate ubiquitin-protein conjugates in the ubiquitin-proteasome system. Previous research shows that ubiquitin-specific protease-19 (USP-19) is up-regulated in mammalian skeletal muscle in some degradative conditions, such as including fasting, diabetes, dexamethasone treatment, and cancer, and its function is associated with muscle atrophy. However, it is still unclear whether USP-19 is involved in muscle atrophy induced by chronic obstructive pulmonary disease. Rats exposed to chronic cigarette smoke and L6 myotubes incubated with cigarette smoke extract (CSE) were studied here. Using western blot analysis and quantitative real-time polymerase chain reaction (qPCR), we observed over-expression of USP-19 and down-regulation of myosin heavy chain (MHC) in both models. Moreover, CSE exposure inhibited myogenic differentiation and myotube formation in L6 myotubes. To explore the mechanism underlying these effects, we investigated the levels of phosphorylated mitogen-activated protein kinases (MAPKs) and total MAPKs. Exposing myotubes to CSE resulted in the general activation of MAPKs such as p38, JNK, and ERK1/2. The ERK inhibitor PD98059 and the p38 inhibitor SB203580 significantly blocked the increase in USP-19 gene expression induced by CSE. Our findings suggest that USP-19 is associated with muscle atrophy in response to cigarette smoke and is a potential therapeutic target. CSE promotes myotube wasting in culture partly by inhibiting myogenic differentiation and acts via p38 and ERK MAPK to stimulate expression of USP-19 in vitro.

Genetic diversity of Haemonchus contortus isolated from sympatric wild blue sheep (Pseudois nayaur) and sheep in Helan Mountains, China.

BACKGROUND: Haemonchus contortus is known among parasitic nematodes as one of the major veterinary pathogens of small ruminants and results in great economic losses worldwide. Human activities, such as the sympatric grazing of wild with domestic animals, may place susceptible wildlife hosts at risk of increased prevalence and infection intensity with this common small ruminant parasite. Studies on phylogenetic factors of H. contortus should assist in defining the amount of the impact of anthropogenic factors on the extent of sharing of agents such as this nematode between domestic animals and wildlife. METHODS: H. contortus specimens (n = 57) were isolated from wild blue sheep (Pseudois nayaur) inhabiting Helan Mountains (HM), China and additional H. contortus specimens (n = 20) were isolated from domestic sheep that were grazed near the natural habitat of the blue sheep. Complete ITS2 (second internal transcribed spacer) sequences and partial sequences of the nad4 (nicotinamide dehydrogenase subunit 4 gene) gene were amplified to determine the sequence variations and population genetic diversities between these two populations. Also, 142 nad4 haplotype sequences of H. contortus from seven other geographical regions of China were retrieved from database to further examine the H. contortus population structure. RESULTS: Sequence analysis revealed 10 genotypes (ITS2) and 73 haplotypes (nad4) among the 77 specimens, with nucleotide diversities of 0.007 and 0.021, respectively, similar to previous studies in other countries, such as Pakistan, Malaysia and Yemen. Phylogenetic analyses (BI, MP, NJ) of nad4 sequences showed that there were no noticeable boundaries among H. contortus populations from different geographical origin and population genetic analyses revealed that most of the variation (94.21%) occurred within H. contortus populations. All phylogenetic analyses indicated that there was little genetic differentiation but a high degree of gene flow among the H. contortus populations among wild blue sheep and domestic ruminants in China. CONCLUSIONS: The current work is the first genetic characterization of H. contortus isolated from wild blue sheep in the Helan Mountains region. The results revealed a low genetic differentiation and high degree of gene flow between the H. contortus populations from sympatric wild blue sheep and domestic sheep, indicating regular cross-infection between the sympatrically reared ruminants.

Differences in airway remodeling and airway inflammation among moderate-severe asthma clinical phenotypes.

BACKGROUND: To identify asthma clinical phenotypes using cluster analysis and improve our understanding of heterogeneity in asthma. METHODS: Clustering approaches were applied to 203 patients who were diagnosed with asthma in XinHua Hospital (January 2012 to December 2015). One hundred and twenty patients underwent multi-slice spiral computed tomography (MSCT) examination and 30 underwent bronchial mucosal biopsy for evaluation of airway remodeling and airway inflammation among the phenotypes. RESULTS: Four groups were identified. Patients in cluster 1 (n=52) had early onset atopic asthma and patients in cluster 2 (n=65) had small airway obstruction and atopic asthma. Cluster 3 (n=52) was a unique group of patients with late-onset and non-atopic asthma. Patients in cluster 4 (n=34) had severe airflow obstruction and obvious airway remodeling as observed on MSCT (P<0.05). According to the immunohistochemistry of IL-5 and IL-17 (P<0.05), the results of clusters 1 and 2 may be attributable to the Th2 immune response, whereas those of clusters 3 and 4 to the Th17 immune response. CONCLUSIONS: Four distinct clinical phenotypes of asthma were identified by cluster analysis. The results of the MSCT and pathological examinations may suggest specific pathogeneses among the phenotypes.

Clinical and pathological features and imaging manifestations of bronchial anthracofibrosis: the findings in 15 patients.

BACKGROUND: Bronchial anthracofibrosis (BAF) has been defined as a luminal narrowing associated with anthracotic pigmentation on bronchoscopy without a relevant history of pneumoconiosis or smoking. The aim of the study is to study the clinical features and imaging manifestations of BAF, and to promote the awareness of this disease. METHOD: Between October 2006 and January 2012, 15 patients were diagnosed at our department as BAF that showed a narrowing or obliteration of lobar or segmental bronchi with anthracotic pigmentation in the overlying mucosa on bronchoscopy. The medical records including clinical features, imaging manifestations, electronic bronchoscopic findings, and pathological features were analysed, and the literature was reviewed. RESULTS: A total of 15 patients were analyzed; 13 were female (86.7%) and two were male (13.3%) and the age range was from 62 to 86 years with a mean age of 74.5 years. Three cases (20.0%) had a history of tuberculosis. The most common clinical symptoms of BAF were cough (100%), expectoration (73.3%), dyspnea (60.0%), and fever (46.7%). Twelve cases displayed mild to moderate obstructive ventilatory dysfunction. In the electronic bronchoscopic evaluation, the most common findings were black bronchial mucosal pigmentation, bronchial stenosis, bronchial occlusion, and bronchial mucosal folds. Pathological evaluation revealed chronic inflammation of the bronchial mucosa, submucosal carbon particle deposition, and mucosal or submucosal fibrosis. Chest CT scans showed that 15 patients had bronchial stenosis or obstruction (direct signs) with the right middle lobe being the most common site (11 cases, 73.3%). The indirect sign was mainly the presence of bronchial obstructive diseases (including secondary infection), represented by 11 cases of pulmonary consolidation (73.3%), seven cases of atelectasis (46.7%), and five cases of nodules (33.3%). The CT mediastinal window showed bronchial lymph node lesions, mediastinal lymph node calcification (12 cases, 80.0%), and enlargement of multiple mediastinal lymph nodes. CONCLUSIONS: The diagnosis of BAF was mainly based on bronchoscopic evaluation. Its pathogenesis is currently unclear, although it may be related to tuberculosis or bio-fuel inhalation. The diagnosis of BAF has important clinical significance, and improved awareness of this disease will contribute to prevention of unnecessary thoracotomies.