Function of abscisic acid in maintenance of maize primary root growth under water deficit

The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file plus two media files.Title from title screen of research.pdf file (viewed on May 1, 2009)Vita.Thesis (Ph.D.) University of Missouri-Columbia 2006.Previous studies suggested that ABA accumulation is required to maintain maize primary root elongation under water deficit and that one of the functions of ABA is to restrict ethylene evolution. These studies were conducted by using carotenoid deficient seedlings to induce ABA deficiency. Using the recently available ABA-deficient mutant vp14, it was confirmed that endogenous ABA accumulation maintains root growth under water stress by restricting ethylene synthesis. Gene expression studies confirmed that the Vp14 is an important regulator of the ABA synthesis required for root growth maintenance under water deficit. Staining for intracellular ROS in vp14 roots indicated that ABA deficiency under water deficit caused excess ROS levels. Moreover, the increase in ROS levels preceded and caused loss of plasma membrane integrity in vp14 roots under water deficits. The results provide conclusive evidence that the maintenance of elongation in the maize primary root requires the accumulation of ABA both to restrict ethylene synthesis and to prevent excess levels of intracellular ROS. A supplemental objective was to develop a method for imaging apoplastic ROS. Increased apoplastic ROS levels occurred specifically in the region of growth maintenance in roots under water deficits. Further work is needed to determine the mechanism by which ABA regulates ROS balance in water-stressed roots.Includes bibliographical reference

Angiotensin receptor-neprilysin inhibitor in patients with heart failure and chronic kidney disease

Despite significant advances in the management of heart failure with reduced ejection fraction (HFrEF), there remains an enormous health problem with high morbidity and mortality over the last few decades. The neprilysin inhibitor enhances the activity of natriuretic peptides, producing vasodilation, natriuresis, and diuresis. Angiotensin receptor blockers inhibit the renin-angiotensin-aldosterone system. Sacubitril/valsartan, a first-in-class angiotensin receptor-neprilysin inhibitor (ARNI), has been shown to improve cardiovascular outcomes in HFrEF and delay the progression of chronic kidney disease (CKD) in patients with HFrEF. The PARADIGM-HF study showed a reduction in diuretic need in the ARNI group. While the use of diuretics is effective in volume control in patients with HFrEF, their use has the potential to adversely affect renal function. Therefore, ARNI therapy could benefit patients with heart failure and CKD by reducing cardiovascular morbidity and mortality and possibly retarding the progression of CKD, although more clinical evidence is required in patients with severe CKD and end-stage renal disease

Refining Historical earthquake Data Through Modeling and Scale Model Tests

This study was performed for the reevaluation of historical earthquake records which occurred in Korea through tests and numerical analyses. For the scale model tests, static and cyclic lateral load tests on wooden frames that constitute a Korean ancient commoner’s house were conducted. Full-scale models of two types of frames were used for testing. Two 1:4 scale models were tested for rock and soil foundation conditions. Scaled real earthquake time histories were inputted for the tests. The peak ground acceleration (PGA) at the collapse of the house at the soil site was 0.25g, whereas PGA for moderate damage at the rock site was 0.6g. The intensity of major historical earthquake records related with house collapses was reevaluated based on the results of these scale mode1 tests. The magnitudes of historical earthquake records related with house collapses were estimated considering the magnitude, epicentral distance, soil condition and aging of the house. Eighteen artificial time histories for magnitudes 6-8, epicentral distances 5 km - 350 km and hard and soft soil condition were generated. The aging effects of the house was modeled as the lateral loading capacity of wooden frames represented by hysteretic stiffness decreased linearly with time

Superparamagnetic Iron Oxide Nanoparticles Coated with Galactose-Carrying Polymer for Hepatocyte Targeting

Our goal is to develop the functionalized superparamagnetic iron oxide nanoparticles (SPIONs) demonstrating the capacities to be delivered in liver specifically and to be dispersed in physiological environment stably. For this purpose, SPIONs were coated with polyvinylbenzyl-O-β-D-galactopyranosyl-D-gluconamide (PVLA) having galactose moieties to be recognized by asialoglycoprotein receptors (ASGP-R) on hepatocytes. For use as a control, we also prepared SPIONs coordinated with 2-pyrrolidone. The sizes, size distribution, structure, and coating of the nanoparticles were characterized by transmission electron microscopy (TEM), electrophoretic light scattering spectrophotometer (ELS), X-ray diffractometer (XRD), and Fourier transform infrared (FT-IR), respectively. Intracellular uptake of the PVLA-coated SPIONs was visualized by confocal laser scanning microscopy, and their hepatocyte-specific delivery was also investigated through magnetic resonance (MR) images of rat liver. MRI experimental results indicated that the PVLA-coated SPIONs possess the more specific accumulation property in liver compared with control, which suggests their potential utility as liver-targeting MRI contrast agent

Cancer-related Fatigue in Patients with Advanced Cancer Treated with Autonomic Nerve Pharmacopuncture

AbstractThe purpose of this study was to observe the effects of autonomic nerve pharmacopuncture (ANP) treatment on cancer-related fatigue (CRF) in patients with advanced cancer. This observational case study was conducted at the East West Cancer Center of Daejeon University's Dunsan Korean Medical Hospital. Two patients were observed. One patient was diagnosed with left thymic cancer metastatic to the left pleura. The other patient had terminal-stage cervical cancer with iliac bone and lumbar 5 metastases. We injected mountain ginseng pharmacopuncture (MGP) into acupoints alongside the spine (Hua-Tuo-Jia-Ji-Xue, EX B2). We examined the patients for CRF using the Korean version of the Revised Piper Fatigue Scale (RPFS-K), which is a self-assessment tool. The scores on the RPFS-K for both patients tended to decrease during the treatment. Laboratory findings, including hematological changes, were also checked. Liver and renal function tests showed that the treatment was safe. Although further large-population studies are necessary, this case study suggests that ANP has a favorable effect on CRF in patients with advanced cancer

Effects of Berberine and Hwangryunhaedok-Tang on Oral Bioavailability and Pharmacokinetics of Ciprofloxacin in Rats

Hwangryunhaedok-Tang (HR) and berberine-containing single herbs are used to treat bacterial infection and inflammatory diseases in eastern Asia. The combination of berberine-containing herbal medicines and ciprofloxacin can be an excellent antibacterial chemotherapy against multidrug resistance bacteria. To evaluate the pretreatment effect of berberine and HR, vehicle, berberine (25 and 50 mg/kg/day), and HR (1.4 g/kg/day) were daily administered to rats for five consecutive days. On day 6, ciprofloxacin was administered (10 mg/kg, i.v. and 20 mg/kg, p.o.) to rats. To assess cotreatment effect of berberine and ciprofloxacin, berberine (50 mg/kg) and ciprofloxacin (20 mg/kg) were coadministered by single oral gavage. Pharmacokinetic data were estimated by noncompartmental model. Compared with ciprofloxacin alone (control group), coadministration of berberine (50 mg/kg) and ciprofloxacin significantly decreased Cmax of ciprofloxacin (P<0.05). In addition, the pretreatment of berberine (50 mg/kg/day) and HR (1.4 g/kg/day) significantly decreased Cmax and AUC0→∞, compared with control group (P<0.05). The oral bioavailability of ciprofloxacin was reduced by cotreatment of berberine and pretreatment of berberine and HR. Our results suggest that the expression of P-glycoprotein and organic anion and/or organic cation transporters (OAT/OCT) could take a role in reduced oral bioavailability of ciprofloxacin by berberine and HR

Deficiency of peroxiredoxin 2 exacerbates angiotensin II-induced abdominal aortic aneurysm

Abdominal aortic aneurysm: Potential enzyme biomarker identified An enzyme with antioxidant properties may provide a biomarker and therapeutic agent to help treat abdominal aortic aneurysm (AAA). AAA involves the structural deterioration of the aorta through chronic inflammation and oxidative stress, and can trigger life-threatening artery rupture. An antioxidant enzyme called peroxiredoxin 2 (PRDX2) is increased in patients with ruptures, but whether its role in AAA is beneficial or detrimental is unclear. Goo Taeg Oh at the Ewha Womans University in Seoul, Jong-Gil Park at the Korea Research Institute of Bioscience and Biotechnology, Daejeon, South Korea, and co-workers examined the effect of PRDX2 on AAA progression. PRDX2 suppressed structural damage in mice, limiting artery dilation and protein degradation. Loss of PRDX2 accelerated AAA development. Measuring levels of PRDX2 may indicate AAA severity in patients, while boosting the enzyme could repair aortic damage