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Background: A six-minute walk test (6MWT) is a reproducible, easily performed test, and is widely used to determine functional exercise capacity in patients with idiopathic pulmonary fibrosis (IPF). However, there is currently a paucity of data on the clinical significance of baseline and serial 6-minute walk tests in patients with IPF, especially in Asian patients. Objectives: We aimed to investigate the clinical significance of serial 6MWT in patients with IPF, especially in Asian patients. Design: This is a single-center retrospective cohort study. Methods: Clinical data of patients diagnosed with IPF at a tertiary center in Korea were retrospectively analyzed. IPF diagnosis was defined according to the clinical guidelines of the American Thoracic Society (ATS)/European Respiratory Society (ERS)/Japanese Respiratory Society/Latin American Thoracic Association. Results: There were 216 patients diagnosed with IPF from December 2012 to January 2022, of whom 198 had a baseline of 6MWT data. The mean age of the cohort was 66.9 ± 8.6, and 89% were male. The non-survivors showed significantly lower six-minute walk distance (6MWD), minimum saturation of peripheral oxygen (SpO2) during 6MWT, forced vital capacity, and diffusing capacity of the lung for carbon monoxide than survivors at baseline. A multivariate Cox analysis demonstrated that lower minimum SpO2 was independently associated with increased mortality rates (Hazard ratio (HR): 1.081, 95% confidence interval (CI): 1.024–1.142, p = 0.005). Higher mortality rates were also associated with echocardiographic-determined pulmonary hypertension (HR: 2.466, 95% CI: 1.149–5.296, p = 0.021) at diagnosis. Among 144 patients with 6MWT results at 12 months, patients with a decline of 50 m or more in the 6MWD showed poorer overall survival than others (median survival: 45.0 months vs 58.0 months, p < 0.001). Conclusions: Baseline lower minimum SpO2 during 6MWT was an independent prognostic factor in patients with IPF, and a decline in 6MWD in serial follow-up was also associated with a poorer prognosis. These findings suggest that both baseline 6MWT and follow-up data are important in the prognostication of patients with IPF. [ABSTRACT FROM AUTHOR]

Background: The risk of serious infection and active tuberculosis in patients with inflammatory bowel disease (IBD) has not been concurrently evaluated based on the use of anti-tumor necrosis factor (TNF)-α agents versus non-anti-TNF biologics (vedolizumab/ustekinumab) in the Korean population. Objectives: We compared the risk of serious infection and active tuberculosis in Korean patients with IBD treated with non-anti-TNF biologics (vedolizumab/ustekinumab) or anti-TNF-α agents. Design: This study was a population-based cohort analysis of nationwide administrative claims data. Methods: Health Insurance Review and Assessment Service claims data (representing 97% of the South Korean population) from between January 2007 and February 2021 were reviewed, and adults with IBD who initiated vedolizumab/ustekinumab or anti-TNF-α treatment (n = 6123) between 2017 and 2020 were enrolled. Intergroup differences in the risk of serious infection requiring hospitalization/emergency department visits or active tuberculosis during the follow-up period were analyzed. Results: In the patients treated with anti-TNF-α agents or vedolizumab/ustekinumab during a mean follow-up of 1.55 ± 1.05 and 0.84 ± 0.69 years, the incidence rates of serious infection were 9.43/100 and 6.87/100 person-years, respectively. Multivariable analysis showed no significant intergroup difference in the risk of serious infection with vedolizumab/ustekinumab or anti-TNF-α treatment; the adjusted relative risk of vedolizumab/ustekinumab compared with anti-TNF-α agents was 0.81 (95% confidence interval 0.46–1.44, p = 0.478). Among patients treated with anti-TNF-α agents and vedolizumab/ustekinumab, the incidence rates of active tuberculosis were 0.87 and 0.37 per 100 person-years, respectively. The relative risk of vedolizumab/ustekinumab compared with anti-TNF-α agents was 0.31 (95% confidence interval 0.07–1.26, p = 0.101). In a subset analysis comparing vedolizumab and ustekinumab with anti-TNF-α agents, similar results were observed. Conclusion: In Korean patients with IBD, non-anti-TNF biologics (vedolizumab/ustekinumab) tended to be associated with a lower risk of serious infection or active tuberculosis than anti-TNF-α agents. [ABSTRACT FROM AUTHOR]

Citrus fruits were sorted based on external qualities, such as size, weight, and color, and internal qualities, such as soluble solid content (SSC), acidity, and firmness. Visible and near-infrared (VNIR) hyperspectral imaging techniques were used as rapid and nondestructive techniques for determining the internal quality of fruits. The applicability of the VNIR hyperspectral imaging technique for predicting the SSC in citrus fruits was evaluated in this study. A VNIR hyperspectral imaging system with a wavelength range of 400–1000 nm and 100 W light source was used to acquire hyperspectral images from citrus fruits in two orientations (i.e., stem and calyx ends). The SSC prediction model was developed using partial least-squares regression (PLSR). Spectrum preprocessing, effective wavelength selection through competitive adaptive reweighted sampling (CARS), and outlier detection were used to improve the model performance. The performance of each model was evaluated using the coefficient of determination (R2) and root mean square error (RMSE). In the present study, the PLSR model was developed using only a citrus cultivar. The SSC prediction CARS-PLSR model with outliers removed exhibited R2 and RMSE values of approximatively 0.75 and 0.56 °Brix, respectively. The results of this study are expected to be useful in similar fields such as agricultural and food post-harvest management, as well as in the development of an online system for determining the SSC of citrus fruits. [ABSTRACT FROM AUTHOR]

The pear pest, Cacopsylla jukyungi (Hemiptera: Psyllidae), is the most damaging insect to commercial pears in South Korea. An assessment of the population genetic characteristics of the species will raise the potential of effective control. In the present study, we developed eight microsatellite markers specific to C. jukyungi and genotyped 132 individuals collected from 11 localities throughout South Korea. Populations showed lower observed heterozygosity than expected heterozygosity and slightly or highly positive values of inbreeding coefficients, suggesting that C. jukyungi is subjected to inbreeding. A strong dependence on commercial pear trees throughout the whole life cycle, even during overwintering, and a nationwide targeting of the overwintered adults are likely contributors to such heterozygosity deficiency. On the other hand, population analyses consistently indicated strong gene flow among populations, implying the presence of persistent factors that have facilitated this process. The nationwide expansion of pear orchards and the replacement with a popular new cultivar during the last 50 years, which may have accompanied the spread of C. jukyungi-bearing pear grafts and scions, are likely causes of such facilitated dispersal. Thus, a management strategy against unintended anthropogenic dispersal of the pear psyllid will be required for better control of C. jukyungi. [ABSTRACT FROM AUTHOR]