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The article investigates the association between exposure to occupational dust and poor idiopathic pulmonary fibrosis (IPF) prognosis. Topics discussed include the occupational and environmental agents that contribute to IPF etiology, respiratory failure as the most common cause of death among IPF patients and the evidence that occupational dust is an aggravating factor for poor IPF prognosis.

Purpose: A recent study demonstrated that exertional desaturation is a predictor of rapid decline in lung function in patients with chronic obstructive pulmonary disease (COPD); however, the study was limited by its method used to detect exertional desaturation. The main purpose of this study was to explore whether exertional desaturation assessed using nadir oxygen saturation (SpO2) during the 6-minute walk test (6MWT) can predict rapid lung function decline in patients with COPD. Materials and Methods: A retrospective analysis was performed on 57 patients with moderate to very severe COPD who underwent the 6MWT. Exertional desaturation was defined as a nadir SpO2 of <90% during the 6MWT. Rapid decline was defined as an annual rate of decline in forced expiratory volume in 1 second (FEV1) =50 mL. Patients were divided into rapid decliner (n=26) and non-rapid decliner (n=31) groups. Results: A statistically significant difference in exertional desaturation was observed between rapid decliners and non-rapid decliners (17 vs. 8, p=0.003). No differences were found between the groups for age, smoking status, BODE index, and FEV1. Multivariate analysis showed that exertional desaturation was a significant independent predictor of rapid decline in patients with COPD (relative risk, 6.8; 95% CI, 1.8 to 25.4; p=0.004). Conclusion: This study supports that exertional desaturation is a predictor of rapid lung function decline in male patients with COPD. [ABSTRACT FROM AUTHOR]

Sum frequency generation (SFG) vibration spectroscopy can selectively detect crystalline cellulose without spectral interference from cell wall matrix components. Here, we show that the cellulose SFG spectrum is sensitive to cellulose microfibril alignment and packing within the cell wall. SFG intensity at 2,944 cm-1 correlated well with crystalline cellulose contents of various regions of the Arabidopsis (Arabidopsis thaliana) inflorescence, while changes in the 3,320/2,944 cm-1 intensity ratio suggest subtle changes in cellulose ordering as tissues mature. SFG analysis of two cellulose synthase mutants (irx1/cesa8 and irx3/cesa7) indicates a reduction in cellulose content without evidence of altered cellulose structure. In primary cell walls of Arabidopsis, cellulose exhibited a characteristic SFG peak at 2,920 and 3,320 cm-1, whereas in secondary cell walls, it had peaks at 2,944 and 3,320 cm-1. Starch (amylose) gave an SFG peak at 2,904 cm-1 (CH methine) whose intensity increased with light exposure prior to harvest. Selective removal of matrix polysaccharides from primary cell walls by acid hydrolysis resulted in an SFG spectrum resembling that of secondary wall cellulose. Our results show that SFG spectroscopy is sensitive to the ordering of cellulose microfibrils in plant cell walls at the meso scale (nm to µm) that is important for cell wall architecture but cannot be probed by other spectroscopic or diffraction techniques. [ABSTRACT FROM AUTHOR]

Background: Gastroesophageal reflux disease (GERD) is one of the most common causes of chronic cough and a potential risk factor for exacerbation of chronic obstructive pulmonary disease (COPD). The aim of this study was to investigate the prevalence and risk factors of GERD in patients with COPD and association between GERD and COPD exacerbation. Methods: Data were collected from the National Health Insurance Database of Korea. The subjects were 40 years old and older, who had COPD as primary or secondary diagnosis codes and utilized health care resource to receive prescriptions of COPD medication at least twice in 2009. Univariate logistic regression was performed to understand the relationship between COPD and GERD, and multiple logistic regression analysis was performed with adjustment for several confounding factors. Results: The prevalence of GERD in COPD patients was 28% (39,987/141,057). Old age, female gender, medical aid insurance type, hospitalization, and emergency room (ER) visit were associated with GERD. Most of COPD medications except inhaled muscarinic antagonists were associated with GERD. The logistic regression analysis showed that the presence of GERD was associated with increased risk of hospitalization (OR 1.54, CI 1.50 to 1.58, p<0.001) and frequent ER visits (OR 1.55, CI 1.48 to 1.62, p<0.001). Conclusions: The prevalence of GERD in patients with COPD was high. Old age, female gender, medical aid insurance type, and many COPD medications except inhaled muscarinic antagonists were associated with GERD. The presence of GERD was associated with COPD exacerbation. [ABSTRACT FROM AUTHOR]

Xyloglucan (XyG) is the dominant hemicellulose present in the primary cell walls of dicotyledonous plants. Unlike Arabidopsis (Arabidopsis thaliana) XyG, which contains galactosyl and fucosyl substituents, tomato (Solarium lycopersicum) XyG contains arabinofuranosyl residues. To investigate the biological function of these differing substituents, we used a functional complementation approach. Candidate glycosyltransferases were identified from tomato by using comparative genomics with known XyG galactosyltransferase genes from Arabidopsis. These candidate genes were expressed in an Arabidopsis mutant lacking XyG galactosylation, and two of them resulted in the production of arabinosylated XyG, a structure not previously found in this plant species. These genes may therefore encode XyG arabinofuranosyltransferases. Moreover, the addition of arabinofuranosyl residues to the XyG of this Arabidopsis mutant rescued a growth and cell wall biomechanics phenotype, demonstrating that the function of XyG in plant growth, development, and mechanics has considerable flexibility in terms of the specific residues in the side chains. These experiments also highlight the potential of reengineering the sugar substituents on plant wall polysaccharides without compromising growth or viability. [ABSTRACT FROM AUTHOR]

Purpose: A new spirometric reference equation was recently developed from the first national chronic obstructive pulmonary disease (COPD) survey in Korea. However, Morris' equation has been preferred for evaluating spirometric values instead. The objective of this study was to evaluate changes in severity staging in Korean COPD patients by adopting the newly developed Korean equation. Materials and Methods: We evaluated the spirometric data of 441 COPD patients. The presence of airflow limitation was defined as an observed post-bronchodilator forced expiratory volume in one second/forced vital capacity (FEV1/FVC) less than 0.7, and the severity of airflow limitation was assessed according to GOLD stages. Spirometric values were reassessed using the new Korean equation, Morris' equation and other reference equations. Results: The severity of airflow limitation was differently graded in 143 (32.4%) patients after application of the new Korean equation when compared with Morris' equation. All 143 patients were reallocated into more severe stages (49 at mild stage, 65 at moderate stage, and 29 at severe stage were changed to moderate, severe and very severe stages, respectively). Stages according to other reference equations were changed in 18.6-49.4% of the patients. Conclusion: These results indicate that equations from different ethnic groups do not sufficiently reflect the airflow limitation of Korean COPD patients. The Korean reference equation should be used for Korean COPD patients in order to administer proper treatment. [ABSTRACT FROM AUTHOR]

The main load-bearing network in the primary cell wall of most land plants is commonly depicted as a scaffold of cellulose microfibrils tethered by xyloglucans. However, a xyloglucan-deficient mutant (xylosyltransferase/xylosyltransferase2 [xx1/xxt2]) was recently developed that was smaller than the wild type but otherwise nearly normal in its development, casting doubt on xyloglucan's role in wall structure. To assess xyloglucan function in the Arabidopsis (Arabidopsis thaliana) wall, we compared the behavior of petiole cell walls from xxt1/xxt2 and wild-type plants using creep, stress relaxation, and stress/strain as says, in combination with reagents that cut or solubilize specific components of the wall matrix. Stress/strain assays showed xxt1/xxt2 walls to be more extensible than wild-type walls (supporting a reinforcing role for xyloglucan) but less extensible in creep and stress relaxation processes mediated by α-expansion. Fusicoccin-induced "acid growth" was likewise reduced in xxt1/xxt2 petioles. The results show that xyloglucan is important for wall loosening by α-expansion, and the smaller size of the xxt1/xxt2 mutant may stem from the reduced effectiveness of α-expansions in the absence of xyloglucan. Loosening agents that act on xylans and pectins elicited greater extension in creep assays of xxt1/xxt2 cell walls compared with wild-type walls, consistent with a larger mechanical role for these matrix polymers in the absence of xyloglucan. Our results illustrate the need for multiple biomechanical assays to evaluate wall properties and indicate that the common depiction of a cellulose-xyloglucan network as the major load-bearing structure is in need of revision. [ABSTRACT FROM AUTHOR]

The main load-bearing network in the primary cell wall of most land plants is commonly depicted as a scaffold of cellulose microfibrils tethered by xyloglucans. However, a xyloglucan-deficient mutant (xylosyltransferase/xylosyltransferase2 [xx1/xxt2]) was recently developed that was smaller than the wild type but otherwise nearly normal in its development, casting doubt on xyloglucan's role in wall structure. To assess xyloglucan function in the Arabidopsis (Arabidopsis thaliana) wall, we compared the behavior of petiole cell walls from xxt1/xxt2 and wild-type plants using creep, stress relaxation, and stress/strain as says, in combination with reagents that cut or solubilize specific components of the wall matrix. Stress/strain assays showed xxt1/xxt2 walls to be more extensible than wild-type walls (supporting a reinforcing role for xyloglucan) but less extensible in creep and stress relaxation processes mediated by α-expansion. Fusicoccin-induced "acid growth" was likewise reduced in xxt1/xxt2 petioles. The results show that xyloglucan is important for wall loosening by α-expansion, and the smaller size of the xxt1/xxt2 mutant may stem from the reduced effectiveness of α-expansions in the absence of xyloglucan. Loosening agents that act on xylans and pectins elicited greater extension in creep assays of xxt1/xxt2 cell walls compared with wild-type walls, consistent with a larger mechanical role for these matrix polymers in the absence of xyloglucan. Our results illustrate the need for multiple biomechanical assays to evaluate wall properties and indicate that the common depiction of a cellulose-xyloglucan network as the major load-bearing structure is in need of revision. [ABSTRACT FROM AUTHOR]

A superhydrophobic property was demonstrated on a cylindrical poly crystalline silicon nanoshell array due to its geometrical properties, even without a hydrophobic coating. The proposed structure showed superior water-repellency compared to a conventional pillar structure with an identical structural dimension. This superhydrophobic property is attributed to an air pillar that exists in the nanoshell. Through the calculation of capillary pressure, the stability of the air pillar was confirmed. Furthermore, a droplet impinging test was conducted on the fabricated cylindrical nanoshell array to verify the robust Cassie state of the proposed structure under a dynamic condition. [ABSTRACT FROM AUTHOR]

The article presents a study on the efficacy of direct DNA sequencing analysis for detecting drug-resistant tuberculosis (TB) on sputum specimens. The study uses 113 sputum samples from 111 patients, allegedly having drug-resistant TB, for DNA sequencing and compares its results. It also analyzes anti-TB drugs optimization based on DNA sequencing and patient treatment results. It concludes that direct DNA sequencing analysis of sputum specimens is useful to detect and treat drug-resistant TB.

Patients with thrombocytopenia caused by various neoplastic and primary bone marrow diseases are susceptible to major hemorrhage. There are few reports addressing the incidence and outcome of gastrointestinal (GI) bleeding in patients with aplastic anemia characterized by long-standing thrombocytopenia. We sought to retrospectively determine the incidence, etiology, clinical outcomes, and risk factors associated with overt GI bleeding in patients with aplastic anemia. We analyzed the medical records of 508 patients with aplastic anemia after excluding patients below 15 years of age or those who underwent stem cell transplantation between January 1, 2002, and December 31, 2007. A total of 32 patients developed overt GI bleeding during this period. We evaluated the site, etiology, outcomes, and major risk factors in these patients who developed GI bleeding episodes. The incidence of GI bleeding was 6.3% (32 of 508 patients) in adult patients with aplastic anemia. The incidence increased to 12.6% (28 of 222 patients) in patients with severe disease. One patient died from massive GI bleeding. Bleeding sites included the esophagus (two patients, 6.3%), stomach (five, 16.3%), duodenum (two, 6.3%), small intestine (five, 15.6%), large intestine (seven, 21.6%), and unknown site (11, 34.4%). Lower GI bleeds mainly caused by neutropenic enterocolitis (NEC) and solitary ulcer developed more frequently than upper GI bleeds. The major risk factors for GI bleeding included old age (P = 0.004, odds ratio (OR) = 1.039), severe aplastic anemia (P < 0.001, OR = 11.934), non-response to therapy (P = 0.001, OR = 5.652), and major bleeding history in another organ (P < 0.001, OR = 6.677). Overt GI bleeding in patients with aplastic anemia more frequently develops in the lower tract than in the upper tract. The risk of GI bleeding is higher in patients with the following risk factors: older age, severe disease, poor response to treatment, and major bleeding history in another organ. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 82-year-old woman who has history of exertional dyspnea, without a history of smoking or other medical conditions. Topics include examines that physical examination and chest computed tomography revealed diffused expiratory wheezing and a large polypoid mass in the distal trachea.

Catamenial haemoptysis is a rare condition caused by thoracic endometriosis that presents as tracheobronchial or pulmonary endometriosis. The authors report a 31-year-old woman with a 1-year history of catamenial haemoptysis, which was diagnosed by chest CT scan during menses and treated successfully by means of video-assisted thoracoscopic surgery of the solitary pulmonary lesion. There was no evidence of recurrence 6 months after the operation. The authors suggest that video-assisted thoracoscopic surgery is an effective therapy for catamenial haemoptysis caused by localized peripheral pulmonary endometriosis. [ABSTRACT FROM AUTHOR]

In this study, we attempted to clarify the roles of fluctuation effects in grain growth. To capture the persistent nature in both space and time of fluctuations due to variations in the local surroundings of individual grains, we developed a local mean-field model. The fluctuation strength in this model is arbitrarily controlled by employing an artificial number, , of nearest neighbor grains. Large-scale numerical computations of the model for various values and initial GSDs were carried out to follow transient behaviors and determine the steady states. This study reveals that, in the classical mean-field model with no fluctuation effects, the steady state is not unique but is strongly dependent upon the initial GSD. However, a small fluctuation drives the mean-field model to reach the Hillert solution, independent of the fluctuation strength and initial GSD, as long as the fluctuation strength is sufficiently small. On the other hand, when the fluctuation is sufficiently strong, the fluctuation pushes the steady state of the mean-field model out of the Hillert solution, and its strength determines a unique steady state independent of the initial GSD. The strong fluctuation makes the GSD more symmetric than the Hillert distribution. Computations designed to mimic actual 2 and 3D grain growth were carried out by taking the number of nearest neighbors of each grain as a function of the scaled grain size. The resultant GSDs in two and three dimensions were compared with the direct simulations of ideal grain growth. [ABSTRACT FROM AUTHOR]

Background: The effects of corticosteroid-based therapy in patients with idiopathic nonspecific interstitial pneumonia (iNSIP), and factors affecting treatment outcome, are not fully understood. We aimed to investigate the long-term treatment response and factors affecting the treatment outcome in iNSIP patients from a multi-center study in Korea.Methods: The Korean interstitial lung disease (ILD) Study Group surveyed ILD patients from 2003 to 2007. Patients were divided into two groups to compare the treatment response: response group (forced vital capacity (FVC) improves ≥10% after 1 year) and non-response group (FVC <10%). Factors affecting treatment response were evaluated by multivariate logistic regression analysis.Results: A total of 261 patients with iNSIP were enrolled, and 95 patients were followed-up for more than 1 year. Corticosteroid treatment was performed in 86 patients. The treatment group showed a significant improvement in lung function after 1-year: FVC, 10.0%; forced expiratory volume (FEV1), 9.8%; diffusing capacity of the lung for carbon monoxide (DLco), 8.4% (p < 0.001). Sero-negative anti-nuclear antibody (ANA) was significantly related with lung function improvement. Sero-positivity ANA was significantly lower in the response group (p = 0.013), compared to that in the non-response group. A shorter duration of respiratory symptoms at diagnosis was significantly associated with a good response to treatment (p = 0.018).Conclusion: Treatment with corticosteroids and/or immunosuppressants improved lung function in iNSIP patients, which was more pronounced in sero-negative ANA and shorter symptom duration patients. These findings suggest that early treatment should be considered in iNSIP patients, even in an early disease stage. [ABSTRACT FROM AUTHOR]