Kyungpook National University

About: Kyungpook National University is a education organization based out in Daegu, South Korea. It is known for research contribution in the topics: Population & Catalysis. The organization has 20497 authors who have published 42107 publications receiving 834608 citations.

Identification of about 30 000 Chemical Components in Shale Oils by Electrospray Ionization (ESI) and Atmospheric Pressure Photoionization (APPI) Coupled with 15 T Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR MS) and a Comparison to Conventional Oil

Abstract: The molecular composition of two shale oils (from U.S. Western and Russian Slanet mines) was studied using 15 T Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) coupled with electrospray ionization (ESI) and atmospheric pressure photoionization (APPI). Together, these techniques allowed for the identification of ∼30 000 chemical components. The class and double-bond equivalence (DBE) distributions of the shale oils were compared to those of conventional oil. Nx classes were abundant in U.S. Western shale oil, and Ox and NOx class compounds were in the Russian Slanet shale oil. The observed class distribution matched well with the high nitrogen content of U.S. Western shale oil and the high oxygen content of Russian Slanet shale oil. Aromatic hydrocarbon was significantly less abundant in the shale oils than in conventional oil. Following studies of the major components, structures were suggested in accordance with the DBE distribution of each class. The DBE distributions of the N1 a...

Physiology and pathophysiology of cyclooxygenase-2 and prostaglandin E2 in the kidney.

Abstract: The cyclooxygenase (COX) enzyme system is the major pathway catalyzing the conversion of arachidonic acid into prostaglandins (PGs). PGs are lipid mediators implicated in a variety of physiological and pathophysiological processes in the kidney, including renal hemodynamics, body water and sodium balance, and the inflammatory injury characteristic in multiple renal diseases. Since the beginning of 1990s, it has been confirmed that COX exists in 2 isoforms, referred to as COX-1 and COX-2. Even though the 2 enzymes are similar in size and structure, COX-1 and COX-2 are regulated by different systems and have different functional roles. This review summarizes the current data on renal expression of the 2 COX isoforms and highlights mainly the role of COX-2 and PGE2 in several physiological and pathophysiological processes in the kidney.

AtGSNOR1 function is required for multiple developmental programs in Arabidopsis.

Abstract: Nitric oxide (NO) has been proposed to regulate a diverse array of activities during plant growth, development and immune function. S-nitrosylation, the addition of an NO moiety to a reactive cysteine thiol, to form an S-nitrosothiol (SNO), is emerging as a prototypic redox-based post-translational modification. An ARABIDOPSIS THALIANAS-NITROSOGLUTATHIONE (GSNO) REDUCTASE (AtGSNOR1) is thought to be the major regulator of total cellular SNO levels in this plant species. Here, we report on the impact of loss- and gain-of-function mutations in AtGSNOR1 upon plant growth and development. Loss of AtGSNOR1 function in atgsnor1-3 plants increased the number of initiated higher order axillary shoots that remain active, resulting in a loss of apical dominance relative to wild type. In addition atgsnor1-3 affected leaf shape, germination, 2,4-D sensitivity and reduced hypocotyl elongation in both light and dark grown seedlings. Silique size and seed production were also decreased in atgsnor1-3 plants and the latter was reduced in atgsnor1-1 plants, which overexpress AtGSNOR1. Overexpression of AtGSNOR1 slightly delayed flowering time in both long and short days, whereas atgsnor1-3 showed early flowering compared to wild type. In the atgsnor1-3 line, FLOWERING LOCUS C (FLC) expression was reduced, whereas transcription of CONSTANS (CO) was enhanced. Therefore, AtGSNOR1 may negatively regulate the autonomous and photoperiod flowering time pathways. Both overexpression and loss of AtGSNOR1 function also reduced primary root growth, while root hair development was increased in atgsnor1-1 and reduced in atgsnor1-3 plants. Collectively, our findings imply that AtGSNOR1 controls multiple genetic networks integral to plant growth and development.