Growth response of Pinus densiflora seedlings to different fertilizer compound ratios in a recently burned area in the eastern coast of Korea

This study was conducted to determine fertilizer compound ratios suitable for soil conditions and tree seedling growth in recently burned areas in Korean forests. Currently, the conventional fertilizer ratio applied to undisturbed forests in Korea is N:P:K 3:4:1. In this study, Japanese red pine (Pinus densiflora S. et Z.) seedlings planted in the burned area were fertilized over four growing seasons with the following NPK compound ratios: unfertilized (CON), 3:4:1, 6:4:1, 3:8:1, and 3:4:2. Fertilization generally increased current-year needle nutrient concentrations of the seedlings, and the chlorophyll a:b ratio in CON was significantly lower than in all fertilized plots. Fertilization significantly affected the growth of the pine seedlings, which had 71–87 % more height growth and 29–67 % increased root collar diameter (RCD) compared to CON. The increases in height and RCD were significantly higher with the 6:4:1 and 3:8:1 ratios than with the 3:4:1 ratio. The 3:4:2 and 3:4:1 fertilizer ratios had no effect on the RCD growth of seedlings. This suggests that the early growth of pine seedlings could be improved by providing high N and P supplies to areas affected by forest fires rather than the conventional fertilizer ratio of 3:4:1 in Korean forest soils. Therefore, application of the suitable fertilization ratio may be a very effective way to reduce reforestation cost as well as to shorten restoration period.     

Design of a description language for generating wrapper to collect biological data

The biological data are scattered in various areas with various formats and they are changing continuously. Therefore, data integration becomes an important issue to provide researcher a dynamic access of data. In the data integration process, the method of extracting heterogeneous data dynamically from the data source is an essential part. Data extraction method using wrapper can provide flexibility and extensibility to an integration system.     

Comparative studies between covalently immobilized and coated chiral stationary phases based on polysaccharide derivatives for enantiomer separation of N‐protected α‐amino acids and their ester derivatives

Liquid chromatographic enantiomer separation of several N‐benzyloxycarbonyl (CBZ) and N‐tert‐butoxycarbonyl (BOC) α‐amino acids and their corresponding ethyl esters was performed on covalently immobilized chiral stationary phases (CSPs) (Chiralpak IA and Chiralpak IB) and coated‐type CSPs (Chiralpak AD and Chiralcel OD) based on polysaccharide derivatives. The solvent versatility of the covalently immobilized CSPs in enantiomer separation of N‐CBZ and BOC‐α‐amino acids and their ester derivatives was shown and the chromatographic parameters of their enantioselectivities and resolution factors were greatly influenced by the nature of the mobile phase. In general, standard mobile phases using 2‐propanol and hexane on Chiralpak IA showed fairly good enantioselectivities for resolution of N‐CBZ and BOC‐α‐amino acids and their esters. However, 50% MTBE/hexane (v/v) for resolution of N‐CBZ‐α‐amino acids ethyl esters and 20% THF/hexane (v/v) for resolution of N‐BOC‐α‐amino acids ethyl esters afforded the greatest enantioselectivities on Chiralpak IA. Also, liquid chromatographic comparisons of the enantiomer resolution of these analytes were made on amylose tris(3,5‐dimethylphenylcarbamate)‐derived CSPs (Chiralpak IA and Chiralpak AD) and cellulose tris(3,5‐dimethylphenylcarbamate)‐derived CSPs (Chiralpak IB and Chiralcel OD). Chiralpak AD and/or Chiralcel OD showed the highest enantioselectivities for resolution of N‐CBZ‐α‐amino acids and esters, while Chiralpak AD or Chiralpak IA showed the highest resolution of N‐BOC‐α‐amino acids and esters. Chirality 2009. © 2008 Wiley‐Liss, Inc.     

Influence of stand density on soil CO2 efflux for a Pinus densiflora forest in Korea

We investigated the influence of stand density [938 tree ha⁻¹ for high stand density (HD), 600 tree ha⁻¹ for medium stand density (MD), and 375 tree ha⁻¹ for low stand density (LD)] on soil CO₂ efflux (R _S) in a 70-year-old natural Pinus densiflora S. et Z. forest in central Korea. Concurrent with R _S measurements, we measured litterfall, total belowground carbon allocation (TBCA), leaf area index (LAI), soil temperature (ST), soil water content (SWC), and soil nitrogen (N) concentration over a 2-year period. The R _S (t C ha⁻¹ year⁻¹) and leaf litterfall (t C ha⁻¹ year⁻¹) values varied with stand density: 6.21 and 2.03 for HD, 7.45 and 2.37 for MD, and 6.96 and 2.23 for LD, respectively. In addition, R _S was correlated with ST (R ² = 0.77–0.80, P < 0.001) and SWC (R ² = 0.31–0.35, P < 0.001). It appeared that stand density influenced R _S via changes in leaf litterfall, LAI and SWC. Leaf litterfall (R ² = 0.71), TBCA (R ² = 0.64–0.87), and total soil N contents in 2007 (R ² = 0.94) explained a significant amount of the variance in R _S (P < 0.01). The current study showed that stand density is one of the key factors influencing R _S due to the changing biophysical and environmental factors in P. densiflora.     

An antioxidant system required for host protection against gut infection in Drosophila

A fundamental question that applies to all organisms is how barrier epithelia efficiently manage continuous contact with microorganisms. Here, we show that in Drosophila an extracellular immune-regulated catalase (IRC) mediates a key host defense system that is needed during host-microbe interaction in the gastrointestinal tract. Strikingly, adult flies with severely reduced IRC expression show high mortality rates even after simple ingestion of microbe-contaminated foods. However, despite the central role that the NF-kappaB pathway plays in eliciting antimicrobial responses, NF-kappaB pathway mutant flies are totally resistant to such infections. These results imply that homeostasis of redox balance by IRC is one of the most critical factors affecting host survival during continuous host-microbe interaction in the gastrointestinal tract.     

Nuclear Translocation of hARD1 Contributes to Proper Cell Cycle Progression

Arrest defective 1 (ARD1) is an acetyltransferase that is highly conserved across organisms, from yeasts to humans. The high homology and widespread expression of ARD1 across multiple species and tissues signify that it serves a fundamental role in cells. Human ARD1 (hARD1) has been suggested to be involved in diverse biological processes, and its role in cell proliferation and cancer development has been recently drawing attention. However, the subcellular localization of ARD1 and its relevance to cellular function remain largely unknown. Here, we have demonstrated that hARD1 is imported to the nuclei of proliferating cells, especially during S phase. Nuclear localization signal (NLS)-deleted hARD1 (hARD1ΔN), which can no longer access the nucleus, resulted in cell morphology changes and cellular growth impairment. Notably, hARD1ΔN-expressing cells showed alterations in the cell cycle and the expression levels of cell cycle regulators compared to hARD1 wild-type cells. Furthermore, these effects were rescued when the nuclear import of hARD1 was restored by exogenous NLS. Our results show that hARD1 nuclear translocation mediated by NLS is required for cell cycle progression, thereby contributing to proper cell proliferation.     

Non–Laboratory-Based Self-Assessment Screening Score for Non-Alcoholic Fatty Liver Disease: Development,Validation and Comparison with Other Scores

Background

Non-alcoholic fatty liver disease (NAFLD) is a prevalent and rapidly increasing disease worldwide; however, no widely accepted screening models to assess the risk of NAFLD are available. Therefore, we aimed to develop and validate a self-assessment score for NAFLD in the general population using two independent cohorts.

Methods

The development cohort comprised 15676 subjects (8313 males and 7363 females) who visited the National Health Insurance Service Ilsan Hospital in Korea in 2008–2010. Anthropometric, clinical, and laboratory data were examined during regular health check-ups and fatty liver diagnosed by abdominal ultrasound. Logistic regression analysis was conducted to determine predictors of prevalent NAFLD and to derive risk scores/models. We validated our models and compared them with other existing methods using an external cohort (N = 66868).

Results

The simple self-assessment score consists of age, sex, waist circumference, body mass index, history of diabetes and dyslipidemia, alcohol intake, physical activity and menopause status, which are independently associated with NAFLD, and has a value of 0–15. A cut-off point of ≥8 defined 58% of males and 36% of females as being at high-risk of NAFLD, and yielded a sensitivity of 80% in men (77% in women), a specificity of 67% (81%), a positive predictive value of 72% (63%), a negative predictive value of 76% (89%) and an AUC of 0.82 (0.88). Comparable results were obtained using the validation dataset. The comprehensive NAFLD score, which includes additional laboratory parameters, has enhanced discrimination ability, with an AUC of 0.86 for males and 0.91 for females. Both simple and comprehensive NAFLD scores were significantly increased in subjects with higher fatty liver grades or severity of liver conditions (e.g., simple steatosis, steatohepatitis).

Conclusions

The new non–laboratory-based self-assessment score may be useful for identifying individuals at high-risk of NAFLD. Further studies are warranted to evaluate the utility and feasibility of the scores in various settings.     

Two enzymes in one; two yeast peroxiredoxins display oxidative stress-dependent switching from a peroxidase to a molecular chaperone function

Although a great deal is known biochemically about peroxiredoxins (Prxs), little is known about their real physiological function. We show here that two cytosolic yeast Prxs, cPrxI and II, which display diversity in structure and apparent molecular weights (MW), can act alternatively as peroxidases and molecular chaperones. The peroxidase function predominates in the lower MW forms, whereas the chaperone function predominates in the higher MW complexes. Oxidative stress and heat shock exposure of yeasts causes the protein structures of cPrxI and II to shift from low MW species to high MW complexes. This triggers a peroxidase-to-chaperone functional switch. These in vivo changes are primarily guided by the active peroxidase site residue, Cys(47), which serves as an efficient "H(2)O(2)-sensor" in the cells. The chaperone function of these proteins enhances yeast resistance to heat shock.     

Genome sequence of strain TW25, a novel member of the genus Ornithinibacillus in the family Bacillaceae

Ornithinibacillus sp. strain TW25, belonging to the family Bacillaceae, was isolated from a dead ark clam during a mass mortality event. Here, the draft genome sequence of strain TW25 (3,843,870 bp, with a G+C content of 36.7%) is reported. This is the first Ornithinibacillus genome to be sequenced.