• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.2
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• pp.124-133
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• 2011

Bacterial blight (BB), cuased by the vascular pathogen Xanthomonas oryzae pv. oryzae, is one of the major threats in rice fields worldwide. In Korea, two resistance genes against BB, Xa1 and Xa3 had been intensively used for developing high quality japonica rice cultivars. Those traditional resistance sources have being rapidly ified by the adopting of BB pathogen through mutations of the corresponding avr-genes, such as K3a exhibiting high compatibility to both Xa1 and Xa3. To expanding genetic resource against BB in Korea, the Suweon506, an introgression line between a Korean japonica cultivar, Hwaseong and a wild relative, Oryza minuta, was be subjected for genetic analysis owing to the BB resistance. Through association analyses between the pathotyping and genotyping results for each $F_2$ progenies, derived from a cross between Suweon506 and a Tongil type cultivar, Milyang23, a major resistant dominant gene is localized on the subterminal region of rice chromosome 4, where at least three BB resistancde genes, Xa1, Xa2, and Xa22, were reported previously.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.3
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• pp.399-407
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• 2012

To evaluate age and gender differences in the relation of cardiovascular risk factors, cognitive impairment, and subclinical carotid atherosclerosis from aged people using by a cross sectional method. Sixty-nine healthy elders living in the community who had not previously undergone carotid ultrasonography were included. We conducted life style surveys, and cognitive function tests including Korean-mini-mental state examination (K-MMSE) and clinical dementia rating-Korean. Various biomarkers from blood were assessed; fasting insulin-like growth factor-1, lipid-profile, high sensitivity C-reactive protein, total homocysteine, glucose, insulin, Homeostasis model assessment (HOMA) for insulin resistance index, vitamin B12, and folate level. Carotid intima-media thickness (C-IMT), and plaques were measured using carotid ultrasonography and aortic ultrasonography, a valid index of atherosclerosis. For the elderly subjects (aged 65-82 years), cognition impairment was more prevalent in females while subclinical atherosclerosis was more prevalentin males. Increased C-IMT has been kept in males, and C-IMT shows increasing trend and the peak at about 80 year-old in females with increasing age. The significant correlations between C-IMT and many vascular risk factors including age, triglyceride, abnormal homocysteinein male, and K-MMSE, insulin, HOMA index and abnormal aortic ultrasonography in female were different in each gender, with the exception of homocysteine (p<0.05). This data suggests that there were differences of age and gender characteristics in terms of subclinical atherosclerosis, cognitive impairment and vascular risk factors in community-living elders. Further larger and longitudinal studies across entire age are required to better understand the effects of risk factors on subclinical atherosclerosis.

• Journal of Biomedical Engineering Research
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• v.20 no.2
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• pp.221-230
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• 1999

A new technique for the preparation of porous polyurethane vascular prostheses was investigated. Synthetic vascular grafts with porous wall have been widely proposed, claiming that strength, suture retention, kink resistance, and other handling properties are improved over those with nonporous solid wall. Related to these facts, the control of pores and compliance match have been very important and interesting issues. Two kinds of polymer sheets were compared. One was the porous PU-sheet made at room temerature by the solvent/non-solvent exchange. And the other was the porous PU-sheet fabricated by thermal phase transition and solvent/non-solvent exchange in the thermal controlled bath. According to the result of the above experiments, polyurethane solution was injected into a mold designed for U-type graft. After freezing at low temperature, solvent was dissolved out with alcohol at < $0^{\circ}C$ and water at room temperature to form porous vessels. The average pore size and pore occupation were easily changed by changing polyurethane concentration and freezing rate. This technique can give a proper pore size for tissue ingrowth, and suitable compliances for matching with arteries and veins. In addition, the fabrication of more complicated shaped vessels such as the U-type vascular grafts is easily controlled by using a mold. This method might give a desired compliact graft for artificial implantaion with the commercially available medical polymers.

• Korean Circulation Journal
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• v.53 no.7
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• pp.425-451
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• 2023

Most patients with heart failure (HF) have multiple comorbidities, which impact their quality of life, aggravate HF, and increase mortality. Cardiovascular comorbidities include systemic and pulmonary hypertension, ischemic and valvular heart diseases, and atrial fibrillation. Non-cardiovascular comorbidities include diabetes mellitus (DM), chronic kidney and pulmonary diseases, iron deficiency and anemia, and sleep apnea. In patients with HF with hypertension and left ventricular hypertrophy, renin-angiotensin system inhibitors combined with calcium channel blockers and/or diuretics is an effective treatment regimen. Measurement of pulmonary vascular resistance via right heart catheterization is recommended for patients with HF considered suitable for implantation of mechanical circulatory support devices or as heart transplantation candidates. Coronary angiography remains the gold standard for the diagnosis and reperfusion in patients with HF and angina pectoris refractory to antianginal medications. In patients with HF and atrial fibrillation, longterm anticoagulants are recommended according to the CHA₂DS₂-VASc scores. Valvular heart diseases should be treated medically and/or surgically. In patients with HF and DM, metformin is relatively safer; thiazolidinediones cause fluid retention and should be avoided in patients with HF and dyspnea. In renal insufficiency, both volume status and cardiac performance are important for therapy guidance. In patients with HF and pulmonary disease, beta-blockers are underused, which may be related to increased mortality. In patients with HF and anemia, iron supplementation can help improve symptoms. In obstructive sleep apnea, continuous positive airway pressure therapy helps avoid severe nocturnal hypoxia. Appropriate management of comorbidities is important for improving clinical outcomes in patients with HF.

• Journal of Chest Surgery
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• v.33 no.5
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• pp.377-384
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• 2000

Background: Numerous studies of safe, long term preservation for lung transplantation have been performed using ex vivo models or in vivo single lung transplantation models. However, a safe preservation time which is applicable for clinical use is difficult to determine. We prepared LPDG solution for lung preservation study. In this study we examined the efficacy of LPDG(low potassium dextran glucose) solution in 24-hour lung preservation by using a sequential bilateral canine lung allotransplant model. Material and Method: Seven bilateral lung transplant procedures were performed using weight-matched pairs(24 to 25kg) of adult mongrel dogs. The donor lungs were flushed with LPDG solution and maintained hyperinflated with 100% oxygen at 1$0^{\circ}C$ for a planned ischemic time of 24 hours for the lung implanted first. After sequential bilateral lung transplantation, dogs were maintained on ventilators for 3 hours: arterial resistance were determined if the recipients hourly after bilateral reperfusion and compared with pretransplant-recipient values, which were used as controls. After 2hours of reperfusion, the chest X-ray, computed tomogram and lung perfusion scan were performed for assessmint of early graft lung function. Pathological examinations for ultrastructural findings of alveolar structure and endothelial structure of pulmonary artery were performed. Result: Five of seven experiments successfully finished the whole assessments after bilateral reperfusion for three hours. Arterial oxygen tension in the recipients was markedly decrased in immediate reperfusion period but gradually recovered after reperfusion for three hours. The pulmonary artery and pulmonary vascular resistance showed singificant elevation(p<0.05 versus control values) but also recovered after reperfusion for three hours(p<0.05 versus immediate period value). The ultrastructural findings of alveolar structure and endothelial structure of pulmonary artery showed reversible mild injury in 24 hours of lung perservation and reperfusion. Conclusion : This study suggests that LPDG solution provides excellent preservation in a canine model in which the dog is completely dependent on the function of the transplanted lung.

• Korean Journal of Pharmacognosy
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• v.45 no.1
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• pp.1-10
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• 2014

Ginsenoside Rg3 (G-Rg3) is one of protopanaxadiol ginsenosides characteristic of red ginseng, steamed and dried ginseng (Panax ginseng), which has recently attracted much attention for its antitumor properties in vitro and in vivo animal models. Experimental studies have demonstrated that it could promote cancer cell apoptosis, inhibit cancer cell growth, the apoptosis of cancer cells, adhesion, invasion and metastasis, and also prevent an angiogenetic formation in prostate, breast, ovarian, colorectal, gastric, liver and lung cancer etc. It has shown the antitumor activities by modulation of diverse signaling pathways, including regulation of cell proliferation mediators (CDKs and cyclins), growth factors (vascular endothelial growth factor), tumor suppressors (p53 and p21), cell death mediators (caspases, Bcl-2, Bax), inflammatory response molecules ($NF-{\kappa}B$ and COX-2), protein kinases (JNK, Akt, and AMP-activated protein kinase) and Wnt/${\beta}$-catenin signaling. In addition, the combination of Rg3 and chemotherapeutic agents have synergistically enhanced therapeutic efficacy and reduced antagonistically side effects. Furthermore, it can reverse the multidrug resistance of cancer cells, prolong the survival duration and improve life quality of cancer patients. Taken together, accumulating evidences could provide the potential of G-Rg3 in the treatment of cancers and the feasibility of further randomized placebo controlled clinical trials.

• Journal of Biomedical Engineering Research
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• v.36 no.5
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• pp.183-190
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• 2015

Invasive blood pressure (IBP) is measured for the patient's real time arterial pressure (ABP) to monitor the critical abrupt disorders of the cardiovascular system. It can be used for the estimation of cardiac output and the opening and closing time detection of the aortic valve. Although the unexplained inflections on ABP make it difficult to find the mathematical relations with other cardiovascular parameters, the estimations based on ABP for other data have been accepted as useful methods as they had been verified with the statistical results among vast patient data. Previous windkessel models were composed with systemic resistance and vascular compliance and they were successful at explaining the average systolic and diastolic values of ABP simply. Although it is well-known that the blood pressure reflection from peripheral arteries causes complex inflection on ABP, previous models do not contain any elements of the reflections because of the complexity of peripheral arteries' shapes. In this study, to simulate a reflection wave of blood pressure, a new mathematical model was designed with four elements that were the impedance of aorta, the compliance of aortic arch, the peripheral resistance, and the compliance of peripheral arteries. The parameters of the new model were adjusted to have three types of arterial blood pressure waveform that were measured from a patient. It was used to find the relations between the inflections and other cardiovascular parameters such as the opening-closing time of aortic valve and the cardiac output. It showed that the blood pressure reflection can bring wide range errors to the closing time of aortic valve and cardiac output with the conventional estimation based on ABP and that the changes of one-stroke volumes can be easily detected with previous estimation while the changes of heart rate can bring some error caused by unexpected reflections.

• Journal of Korean Academy of Nursing
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• v.23 no.4
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• pp.528-543
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• 1993

Vitamin E, which has its advocates in the treatment of diabetes mellitus. autoimmune disease, cancer and peripheral vascular and thromboembolic disease, has now been alleged to have a powerful antioxident effect and to affect various biological activities such as fertility factor, inhibition of human platelet aggregation and stabilization of biological membranes. The present study was designed to test whether vitamin I(alpha-tocopherol) can : (1) enhance the hemagglutinin response to sheep red blood cells (SRBC), (2) modulate Arthus and delayed type hypersensitivity(DTH) to SRBC and contact hypersensitivity to dinitrofluorobenzene (DNFB). (3) enhance the mitogenic response of murine splenocyte, (4) decrease the recovery of Cryptococcus neoformans from brain, lung, liver, spleen and kidney of infected mice and (5) have an inhibitory or enhancing effect on the induction of active systemic anaphylaxis(ASA) induced by chicken-gamma globulin (CGG) in mice. Mice were given either intramuscular injections of 0.3ml (300mg) of vitamin I before immunization or were infection for 10 consecutive days or were given by vitamin I esophageal intubation, 0.1ml(100mg), for 20 days before sacrifice for the mitogenic response experiments. It was found that vitamin E treated mice showed a significant enhancement in hemagglutinin response, Arthus reaction and DTH to SRBC and contact hypersensitivity to DNFB. There was no significant difference in the mitogenic response to phytohemagglutinin(PHA), but the response to concanavalin A(ConA) or pokeweed mitogem(PWM) was increased in vitamin E-treated mice. Interestingly, the vitamin E administration before C. neoformans infection decreased significantly the recovery of C. neoformans from brain lung, liver, spleen and kidney of the infected mice as compared with that of the control mice, strongly suggesting that vitamin E pretreatment may increase the resistance of mice to the fungal infection. Unexpectedly, vitamin E administration enhanced the production of CGG -induced ASA. Taken together, it can be concluded that vitamin I administration may in-crease the humoral and cellular immune response and resistance. to C. neoformans infection, but enhance the induction of ASA to CGG. Further studies are necessary to clarify the underlying mechanism accounting for these effects.

• Research in Plant Disease
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• v.11 no.1
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• pp.35-38
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• 2005

The occurrence of Fusarium wilt in strawberry fields in Korea was assessed from 2001 to 2003. Fusarium wilt was found from June to August in nursery beds, from September to October after planting in production beds, and from January to March during harvesting period. The symptoms were root rots, discolored vascular tissue in the crown and deformation and yellowing of central leaflets. The disease occurred in up to 30% of plants in 37 of 214 fields surveyed. Fusarium wilt occurred from cvs. ‘Dochiodome’, ‘Maehyang’, ‘Redpearl’, ‘Samaberry ’ and ‘Akihime’ and more severe from cvs. ‘Samaberry’, ‘Maehyang’ and ‘Dochiodome’. Infested soils had high salt concentrations, high nitrogen, phosphate concentrations and low pH. The results of pathogenicity test showed that Fo47 and Fo79 isolated from cvs. ‘Dochiodome’ and ‘Samaberry’ were strong pathogenic to all of four cultivars, and ‘Dochiodome’, ‘Redpearl’, ‘Maehyang’ were relatively susceptible to the all isolates.

• Journal of Korean Society of Forest Science
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• v.82 no.4
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• pp.337-346
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• 1993

Experiments were performed to find out the effects of simulated acid rain(SAR) of pH 4.0 or pH 2.5 for 12 weeks on stomatal resistance, wettability and anatomical changes in Quercus acutissima and Ginkgo biloba seedlings. As a control, distilled water with a pH 6.5 was also sprayed. Stomatal resistance of Q. acutissima and of G. biloba remarkably increased after exposure to SAR. SAR increased the wettability of Q. acutissima leaves measured with water blue solution and of G. biloba leaves measured by leaf contact angle method. Anatomical changes in the leaves of Q. acutissima affected by SAR were the partial damage of epidermis and parenchymatous cells. Scanning electron microscopical observation showed that the number of trichomes in the leaves of Q. acutissima treated with SAR markedly decreased and the erosion of epicuticular wax was significant. No distinct damage was found in the G. biloba leaves at pH 4.0, while epidermis and vascular tissue were collapsed at pH 2.5. No significant alteration of surface structures in this tree species was observed.