Tilt test에 依한 循環器機能變化에 關한 硏究

朴舜昌,徐舜圭 고려대학교 의과대학 1984 고려대 의대 잡지 Vol.21 No.1

The Cardiovascular functions are regulated by autonomic nervous system and many physical and hormonal or chemical tests for evaluation of this function have been used. Auther considered that the head-up tilt test may be simple and easy appropriate method to evaluate the function of baroreflex control of cardiovascular functions. Since there is no report on normal and diseases by this method in Korea, auther studied the changes of cardiovascular function by 70 degree Head-up Tilt test using tilting table in 41 cases of normal adult(age 20-39 year group, 25 cases, age 60-75 year group, 16 cases), 16 cases of untreated mild essential hypertension, 9 cases of treated hypertension with pindolol and clonidine and 4 cases of diabetes mellitus with peripheral neuropathy. The cardiovascular functions studied were heart rate, blood pressure and systolic time interval (PEP, ET, PEP/ET, QS_(2)) at 1,5,12 minutes after the head-up tilt. The results were as follows; 1. In normal adult, after 70 degree head-up tilt, the cardiovascular functions were changed since 1 minute and the heart rate increased (average 13/min. after 5 minutes), systolic blood pressure decreased slightly (average 2 ㎜Hg after 5 minutes), diastolic blood pressure increased (average 6 ㎜Hg after 5 minutes), pre-ejection period(PEP) prolonged (average 18 msc increase after 5 minutes), PEP/ET increased (average 0.148 after 5 minutes), ET was shortend (average 52 msc decrease after 5 minutes) and QS_(2) was shortend (average 32 msc decrease after 5 minutes). The systolic blood pressure change was least noticeable up to 12 minutes after the tilt and the heart rate corrected systolic time intervals showed also similar changes. 2. Comparing the change of above cardiovascular functions in young adult and old adult, the changes of the functions were less marked in old adult than in young adult and the systolic blood pressure was rather slightly increased at 1 and 5 minute in old adult and decreased at 12 minute after tilt than control value. 3. In untreated mild essential hypertension, the changes of cardiovascular functions after head-up tilt were less than normal adult which was indicative of reduced baroreflex sensitivity. 4. In treated hypertension and diabetic patients, the changes were less marked than those of untreated hypertension. 5. The test of change of heart rate, blood pressure and systolic time interval by 70 degree head-up tilt test is considered to be a simple appropriate test for the evaluation of sensitivity of the baroreflex.

Vegetation change and emerging research feedback for Korean National Long Term Ecological Research (KNLTER)

Cho, Yong-Chan,Lee, Chang-Seok,Cho, Hyun-Je,Lee, Kyu-Song,Park, Pil-Sun The Ecological Society of Korea 2011 Journal of Ecology and Environment Vol.34 No.1

Various responses of forest ecosystems to climate change underscore the need to improve our understanding of the environmentally-driven changes in forests, most effectively by long-term monitoring protocols. We have explored vegetation dynamics based on changes in community structure, species composition, diversity and demographics in four Korean National Long Term Ecological Research (KNLTER) sites--Mt. Nam, Mt. Jeombong, Mt. Worak, and Mt. Jiri--between 2004 and 2009. Most of the sites and forests studied exhibited increments in total basal area, but this was not observed in Quercus mongolica forests in Mt. Nam and Mt. Worak. Stem density exhibited various changes. Altitude gradient was the representative factor in differences in species composition. Two patterns of compositional change--convergence and divergence--were detected. The vegetation of Mt. Nam and Q. mongolica community of Mt. Work showed relatively larger changes in composition. However, in the other sites, few changes were observed. Changes of species richness were not notable except for Mt. Nam, where three species were added in the pine forest, whereas one species disappeared in the oak forest. In the oak forests, mortality rate was as follows (in descending order): Mt. Nam (25.5%), Mt. Jeombong (24.3%), Mt. Worak (16.4%) and Mt. Jiri (0.8%). In the pine forest, the recruitment rate was as follows (in descending order): Mt. Nam (63.7%), Mt. Worak (12.9%), Mt. Jeombong (7.6%) and Mt. Jiri (7.3%). The mortality rate and change rate of basal area were strongly negatively correlated (r = -0.9, P = 0.002), and the recruitment rate and change rate of density were positively correlated (r = 0.77, P = 0.026). In the KNLTER sites, larger vegetation changes were attributed to anthropogenic activities such as salvage logging. Suppression or competition for resources would also affect these changes. Research suggestions such as monitoring to clarify the causes of species mortality were discussed.

Interaction of Ribose - binding Protein with Trg Chemosensory Transducer in Escherichia coli

Park, Chang Kyu,Jung, Kwang Hwan 한국유전학회 1990 Genes & Genomics Vol.12 No.4

The Trg transducer of E. coli, located in cytoplasmic membrane mediates attractant response to ribose. The periplasmic ribose-binding protein (RBP) is encoded by rbsB gene and is thought to interact with Trg transducer. Ligand-occupied ribose-binding protein is supposed to exert chemotatic response by binding to the Trg transducer and to transport ribose into the cytoplasm. To study the interaction of RBP with Trg, we used trg-8 mutation (Arg85His) that has specific defects in chemotactic response to ribose. We have mutagenized pA112 plasmid containing rbsB gene with hydroxylamine. The mutagenized rbsB plasmids were introduced into the strain that has trg-8 mutation and then ribose taxis positive transformants were screened on ribose swarm plate. Four suppressors that restore ribose taxis have been isolated. Two of the mutations were sequenced by DNA sequencing to find their mutational changes. One has Glu191Lys change and the other Pro65Ser. These results suggest that the residues of 65 and 191 of RBP are important for the interaction with Trg transducer. The structural role and significance of these residues in receptor interaction are discussed based on their locations in three dimensional structure of RBP generated by computer modelling.

젊은층의 성인남자에서 비만 및 체지방의 분포가 인슐린 대사율 및 인슐린 감수성에 미치는 효과

박경수,이병두,박용수,홍성관,장학철,박도준,박중열,이홍규,고창순,민헌기 대한의학협회 1990 대한의학협회지 Vol.33 No.7

Post mortem insect colonization and body weight loss in rabbit carcasses

Park Jun‐Kyu,Kim Chang‐Jun,Do Yuno 한국곤충학회 2020 Entomological Research Vol.50 No.12

This study considers the impact of various treatments of rabbit carcasses on post mortem insect colonization and weight loss. A statistically accurate time for the change in carcass weight and insect access time was determined using time series analysis depending on different carcass treatments that determined insect access. The decomposition stage was relatively short. Fifteen freshly killed white rabbits (Oryctolagus cuniculus) weighing between 2.5 kg and 4.5 kg were used as animal models in this study. Three carcasses were treated in each of five ways: normal, burnt, wrapped, hung, and immersed. A total of thirteen insect species were attracted to normal, burnt, and hung carcasses. Insects were not collected from sealed and immersed carcasses. The normal and burnt carcasses had a higher number of species and abundance compared to hung carcasses. The present study found no difference in insect colonization in normal and burnt carcasses. The determination of the weight of remaining carcass was clearly divided into the insect‐accessible (i.e., normal, burnt, and hung carcasses) and insect‐inaccessible carcasses (i.e., sealed and immersed carcasses), although no difference was found in the decrease in the rate of the remaining carcass in insect‐inaccessible carcasses.

Stable p-type properties of single walled carbon nanotubes by electrochemical doping

Park, Chang-Soo,Lee, Cheol Jin,Kim, Eun Kyu The Royal Society of Chemistry 2015 Physical Chemistry Chemical Physics Vol.17 No.25

<P>We report a highly stable p-type doping for single walled carbon nanotubes using an electrochemical method. The Raman spectroscopy showed the upshift of the G-band when the applied potential increased. Furthermore, the carbon core level shifted as much as 0.14 eV in binding energy of XPS measurement, which is an evidence of p-type doping with a Fermi level change. The highly doped SWCNTs at an applied potential of 1.5 V during the electrochemical doping process showed long time stability, as long as 28 days.</P> <P>Graphic Abstract</P><P>We report a highly stable p-type doping for single walled carbon nanotubes using an electrochemical method. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c5cp01667c'> </P>

무증상 갑상선기능저하증 환자에서 Thyroxine 치료에 따른 혈청 지질 및 아포지단백의 변화

조보연,신찬수,김원배,고창순,김성연,박혜영,박건상,이홍규,박형규,김숙경 대한내분비학회 1996 Endocrinology and metabolism Vol.11 No.1

Background: Subclinical hypothyroidism(SCH) is a common biochemical abnormality which can be found in routine screening tests of thyroid function. We are increasingly faced with the question of whether its an indication for thyroxine replacement therapy. The effect of thyroxine replacement on lipid profile in SCH has aroused a great interest because of an association of overt hypothyroidism(OVH) with hyperlipidemia and increased risk of coronary artery disease. Method: We prospectively evaluated the changes in lipids and apoproteins before and after thyroxine replacement therapy in 23 patients with SCH and in 37 patients with OVH. We measured serum total cholesterol and triglyceride using autoanalyzer, high density lipoprotein(HDL) chole-sterol by dextran sulfate method, Apo A1 and Apo B by immunonephelometric assay. Results: Thyroxine replacement therapy significantly decreased total cholesterol, low density lipoprotein(LDL) cholesterol and apo B levels, but did not affect the level of triglyceride, HDL cholesterol or apo AI in patients with OVH. In SCH, thyroxine replacement therapy with the doses to normalize serum TSH concentrations also decreased significantly the level of cholesterol and LDL cholesterol albeit apo B levels did not change. Moreover, in most of patients with OVH (11 of 12) and in all of patients with SCH(5 of 5) who had had hyperchlesterolemia before treatment, thyroxine replament normalized their cholesterol and LDL cholesterol levels. Conclusion: In regard to the beneficial changes in blood lipid levels, patients with SCH should be treated, especially in cases who have other risk factors for the development of atherosclerosis. If thyroxine replacement only will reduce the incidence of coronary artery disease in SCH remains to be elucidated by long-term prospective studies(J Kor Soc Endocrinol 11:41-51, 1996).

Original Article : Morphologic Characteristics of the Outer Retina in Cone Dystrophy on Spectral-domain Optical Coherence Tomography

( Soo Chang Cho ),( Se Joon Woo ),( Kyu Hyung Park ),( Jeong Min Hwang ) 대한안과학회 2013 Korean Journal of Ophthalmology Vol.27 No.1

Purpose: To investigate the morphologic changes in the outer retina of patients with cone dystrophy, using spectral-domain optical coherence tomography (SD-OCT). Methods: The medical records of 15 cone dystrophy patients examined from January 2007 to January 2012 were reviewed retrospectively. All patients underwent ophthalmic evaluation including best-corrected visual acuity (BCVA), color vision testing, fundus examination, full-field standard electroretinography (ERG), multifocal (mf) ERG, and SD-OCT. Qualitative and quantitative SD-OCT data and ERG responses were analyzed and compared among the patient categories and the normal control group. Results: There were 4 major categories of SD-OCT findings, based on the status of the ellipsoid portion of the photoreceptor inner segment (ISe), outer segment (OS) contact cylinder, and retinal pigment epithelium (RPE) layer. Category 0 showed no structural abnormalities. Category 1 showed foveal ISe loss and obscurity of the border between the ISe band and the external limiting membrane (ELM). Category 2 showed foveal thinning and focal foveal ISe disruption with an intact ELM. Category 3 showed foveal thickening and perifoveal disruption of the ISe layer. Category 1 to 3 showed OS contact cylinder layer absence and RPE thickening. The patients in category 0 tended to be younger (mean, 10.0 years) than those in categories 1 to 3 (mean, 17.6 years), although this difference was not statistically significant. Category 1 to 3 patients exhibited statistically significant thinning of the central retina and outer nuclear layer and thickening of the RPE layer relative to the category 0 and normal control group. There was a significant correlation between the central foveal thickness and BCVA in the patients with cone dystrophy. ERG and mfERG responses did not differ significantly among the different cone dystrophy categories. Conclusions: The morphologic features of cone dystrophy as revealed by SD-OCT, could be categorized as either normal or 1 of 3 different types of outer retinal changes. The presence of normal retinal structures in young cone dystrophy patients with functional impairment (category 0) indicates that electrophysiologic studies are superior to current imaging modalities for the early diagnosis of cone dystrophy. The characteristic SDOCT findings in cone dystrophy patients may aid in differential diagnosis and be useful for future research on the pathology of cone dystrophy.

Label-free DNA detection with a nanogap embedded complementary metal oxide semiconductor

Kim, Chang-Hoon,Jung, Cheulhee,Lee, Kyung-Bok,Park, Hyun Gyu,Choi, Yang-Kyu IOP Pub 2011 Nanotechnology Vol.22 No.13

<P>A nanogap embedded complementary metal oxide semiconductor (NeCMOS) is demonstrated as a proof-of-concept for label-free detection of DNA sequence. When a partially carved nanogap between a gate and a silicon channel is filled with charged biomolecules, the gate dielectric constant and charges are changed. When the gate oxide thickness reduces, the threshold voltage is significantly affected by a change of the charges, whereas it is scarcely influenced by a change of the dielectric constant. In the case of DNA, those two factors act on the threshold voltage oppositely in an n-channel NeCMOS but collaboratively in a p-channel NeCMOS because of the negative charges of DNA. Hence, a p-channel NeCMOS with a thin gate oxide is more attractive for DNA detection because it enhances the shift of threshold voltage; that is, it improves the sensitivity of DNA detection. In addition, the shift of threshold voltage according to the nanogap length is also investigated and the longer nanogap shows more shift of the threshold voltage.</P>

Rat의 복강내에 투여한 5-fluorouracil-polyglycolic acid 제형이 장기에 미치는 영향에 관한 연구

강대영,송규상,최정목,노승무,정경수,오정연,김진향,양준묵,최선웅,이진호,조준식,민병무,김용백,김창식,박근성,김승영,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

For more effective intraperitoneal chemotherapy, the authers made 5-fluorouracil-polyglycolic acid composite disks(FU-PGA disks) with 5-fluorouracil and polyglycolic acid, a biodegradable polymer. We inserted the FU-PGA disk into the peritoneal cavites of Sprague-Dawley male rats, the control and three experimental groups; one FU-PGA disk insert group(300mg/kg), two FU-PGA disk insert group(600mg/kg), and three FU-PGA disk insert group(900mg/kg). The control group received a similar number of PGA disk inserts. A pharmacokinetic study was performed to measure the 5-fluorouracil concentration in the peritoneal fluid, blood, and tissues(liver, kidney and heart) at 24 hours, 72hours and 168 hours after insertion of the FU-PGA disk. Light and electron microscopic studies were done. The results were as follows: 1) The number of white blood cells and platelets decreased after FU-PGA insertion. The degree was proportional to the duration and amounts inserted. The change in the number of red blood cells varied slightly. 2) Light microscopically, slight changes were noted at 168 hours in the 3 disk insert group (900mg/kg). Mild fatty change and hepatocyte degeneration around the central veins of the liver were noted, with vacuolar degeneration in the proximal convoluted tubules of the kidney. 3) Electron microscopically,the liver showed focal increases of lipid droplets in the hepatocytes, and irregular nuclear membrane with focal nucleolar segregation of the fibrillar and granular elements. Also the double membranous structure of the hepatocytes and Kupffer cells was widened with bleb formation. The kidney showed wide separation of the nuclear double membrane in the proximal convoluted tubular cells and mesangial cells, with vacuolation and myelin figure formation in the mitochondria of the proximal convoluted tubular cells, at 72 hours and 168 hours in the 2 to 3 FU-PGA insert groups. The heart showed focal loss of cristae,vacuolation and myelin figure formation in the mitochondria of the 2 to 3 FU-PGA insert groups. In conclusion, despite the large amont of FU-PGA inserted, the histopathological changes in the liver, kidney and heart were slight, and consonant with the very low amount of 5-fluorouracil concentrations detected in the liver, kidney and heart. The above results suggest that the FU-PGA composite can serve as a new device for releasing drugs in a controlled manner and easily targeted to intraperitoneal organs. This device can improve the efficacy of intraperitoneal chemotherapy for gastric cancer.