Biomedical subjects

J T Kim

Publications and source records attributed to J T Kim.

At least 19 recordsLinked to original sources

PubMed2004

Dissociation energies of molecular hydrogen and the hydrogen molecular ion.

We have obtained improved values for the dissociation energies of molecular hydrogen and its ion by using a high-resolution pulse-amplified laser to probe the second dissociation limit. The onset of the vibrational continuum is observed by state-selective detection of the atomic products of dissociation, and several auxiliary measurements link the results to the ground state. The dissociation energies are accurate to 0.010-0.026 cm(-1), improving previous measurements by a factor of 3-7. Agreement with ab initio calculations is good for H2, D2, and their ions, but not for HD and HD+.

Journal Article↗

PubMed2004

Domestic wastewater reclamation by submerged membrane bioreactor with high concentration powdered activated carbon for stream restoration.

This study focuses on the practical application of high concentration powdered activated carbon coupled membrane bio-reactor to domestic wastewater reclamation. The study was conducted in three parts, such as analysis of secondary domestic wastewater effluent, design and operation parameter evaluation and reclaimed water quality estimation for stream restoration. The organic concentration was 25.2-80.2 mgCOD(Cr)/L for the effluent of three domestic wastewater treatment plants. Around 50-75% of the COD was low molecular substances less than 1,000 which were quite biodegradable. The sawdust PAC was estimated to be proper adsorbent for the organics in the secondary effluents. Its Freundlich constant, K value was 5.847 and 1/n, 0.36. Using a system consists of single reactor with high concentration PAC (80 g/L) and submerged hollow fiber MF membrane module with nominal pore size of 0.1 microm, design and operation parameters were obtained, such as HRT of the bioreactor (2.5 hr), PAC concentration (80 g/L), the initial flux (less than 0.5 m/day) and intermittent suction cycle (12 min. suction and 3 min. idling). Organic removal by the system was high enough to produce reclaimed water for urban stream restoration The effluent organic concentration was at the level of 2 mg/L in terms of TOC (around 5 mg/L as COD(Cr)). Substances with molecular weight cut off < 1,000 were removed mostly by adsorption and biodegradation. Those above 1,000 were rejected at PAC cake layer on the membrane and gradually degraded by microorganisms during extended contact.

Bioreactors↗

PubMed2004

Organic and detergent degradation in combined O3/UF for domestic laundry wastewater reclamation.

This paper focuses on the evaluation of organic and detergent degradation in a combined Ozone/UF system for domestic laundry wastewater reclamation. Formation of by-product was investigated by GC/MS for the reclaimed water. Ozone was injected into the raw wastewater in a 10 L contact tank and the wastewater was circulated through the membrane module for inner pressurized cross-flow filtration. The concentrate was returned back to the contact tank. The membrane used in this experiment was hollow fiber polysulfone UF membrane with MWCO 10,000. It has an effective filtration area of 0.06 m2. The experiment was carried out with intermittent ozone injection, 5 min injection and 10 min idling. Ozone was dosed at the concentration of 1.5 mg/L. The flux of the UF could be maintained at 0.24 m/d under filtration pressure 40-45 kPa and water temperature, 20-22 degrees C. The organic removal efficiency by the system was 90% in terms of COD. Ozone was considerably effective to degrade organics in the wastewater. Molecular weight of organics in the raw waste was mostly greater than 10,000 (72% of 950 mgCOD/L). However 86% of effluent COD (94-100 mg/L) was composed of organics smaller than MWCO 500 by ozone injection. No harmful by-products by ozone contact were detected from the analysis of treated water using GC/MS. It was identified that residual organics in the treated water were 1,1'-Oxybisbenzene, Octadecanoic acid, Squalene and Benzenmethanol, etc., which were additives contained originally in the detergent. Consequently the reclaimed water quality could be estimated safe enough to recycle for the rinsing cycle in a washing machine.

Biodegradation, Environmental↗

PubMed2003

Sputum eosinophilia in cough-variant asthma as a predictor of the subsequent development of classic asthma.

BACKGROUND: A significant proportion of patients diagnosed with cough-variant asthma eventually manifest classic asthma signs, such as wheezing and dyspnoea. The aim of this study was to investigate whether the percentage of eosinophils and/or concentration of eosinophilic cationic protein (ECP) in sputum induced from patients with cough-variant asthma can predict the development of classic asthma. METHODS: Sixty-two children with cough-variant asthma were prospectively studied for 4 years. At the initiation of the study, sputum was induced with hypertonic saline, and the sputum samples were analysed for total and differential cell counts, and for ECP. Each subject was checked clinically at least every 3 months, and details of classic asthma signs experienced during the intervening periods were taken. RESULTS: Twenty-four (47.1%) of the 51 subjects available for follow-up developed signs of classic asthma, while 27 did not. The only significant difference in the sputum parameters between these two groups was a higher percentage of sputum eosinophils in subjects who developed classic asthma. A significant association was found between sputum eosinophil percentage and classic asthma development, but not between the concentration of sputum ECP and classic asthma development. CONCLUSION: Sputum eosinophilia in cough-variant asthma may be a correlate of the later development of classic asthma. This suggests that sputum differential cell counts may be useful in the clinical management of patients with cough-variant asthma, as they may enable the prediction of the subsequent classic asthma development.

Adolescent↗

PubMed2001

Total synthesis of microtubule-stabilizing agent (-)-laulimalide.

An enantioselective first total synthesis of laulimalide (1) is described. Laulimalide, a remarkably potent antitumor macrolide, has been isolated from the Indonesian sponge Hyattella sp. and the Okinawan sponge Fasciospongia rimosa. Laulimalide represents a new class of antitumor agents with significant clinical potential. The synthesis is convergent and involved the assembly of C(3)-C(16) segment 4 and C(17)-C(28) segment 5 by Julia olefination. The sensitive C(2)-C(3) cis-olefin functionality was installed by Yamaguchi macrolactonization of a hydroxy alkynic acid followed by hydrogenation of the resulting alkynoic lactone over Lindlar's catalyst. Initial attempts of intramolecular Still's variant of Horner-Emmons olefination between the C(19)-phosphonocetate and C(3)-aldehyde provided a 1:2 mixture of cis- and trans-macrolactones. The trans-isomer was photoisomerized to a mixture of cis- and trans-isomers. The other key steps involved ring-closing olefin metathesis to construct both dihydropyran units, stereoselective anomeric alkylation to functionalize the dihydropyran ring, stereoselective reduction of the resulting alkynyl ketone to set the C(20)-hydroxyl stereochemistry, and a novel Julia olefination protocol for the installation of the C(13)-exo-methylene unit. The sensitive epoxide at C(16)-C(17) was introduced in a highly stereoselective manner by Sharpless epoxidation at the final stage of the synthesis.

Animals↗

PubMed2001

Cloning and characterization of tissue inhibitor of metalloproteinase-3 (TIMP-3) from shark, Scyliorhinus torazame.

We cloned the full-length cDNA encoding TIMP-3 from the cartilage of cloudy dogfish, Scyliorhinus torazame. The entire open reading frame was composed of 645 nucleotides and 214 residues including 12 conserved cysteines and asparagine-184, a putative site for N-linked sugars. It showed about 72% identity to those of other species based on the deduced amino acid sequence. The mRNA of shark TIMP-3 were expressed abundantly in brain and cartilage tissues. To investigate the roles of shark TIMP-3, an expression vector was constructed and transfected into HT1080 human fibrosarcoma cells. Overexpression of shark TIMP-3 reduced the activity of MMP-2 in gelatin zymography. Through human Alu PCR based CAM assay, we also confirmed that shark TIMP-3 transfected HT1080 cells had less intravasation effects.

Amino Acid Sequence↗

PubMed2001

Cephalometric markers to consider in the treatment of Class II Division 1 malocclusion with the bionator.

The principal aims of this study were to find the cephalometric predictors for good treatment results of bionator therapy and to justify bionator therapy as an early phase I treatment for patients with Class II Division 1 malocclusion. Forty subjects who had Class II Division 1 malocclusion and who were treated with the bionator were selected for this study. They were classified into a good treatment result group and a poor treatment result group in reference to the posttreatment molar relationship, posttreatment overbite and overjet, posttreatment profile, and existence of relapse. Thirty-one cephalometric variables were analyzed on the pretreatment lateral cephalograms by t-test to evaluate differences between the 2 groups. The variables that differed significantly were analyzed by discriminant analysis to assess their predictability. The study showed that horizontal growth pattern, close to normal anteroposterior relationship between the maxilla and mandible, upright mandibular incisor, and retrusive lower lip were important predictors for good results. In particular, protrusion of the lower lip was the most important factor for the determination of the treatment results. In addition, the treatment times were much shorter for patients with these good predictors. The present study supports the premise that bionator therapy can produce clinically stable and favorable results if the patients are appropriately selected with the use of these diagnostic criteria.

Activator Appliances↗

PubMed2001

Expression of vascular endothelial growth factor and inducible nitric oxide synthase in pterygia.

PURPOSE: To evaluate the expression of vascular endothelial growth factor (VEGF) in pterygium and investigate the interrelationships between VEGF and nitric oxide (NO) in the development of pterygia. METHODS: Specimens of normal conjunctiva acquired incidentally to conjunctival transplantation during pterygium and strabismus surgery and the excised pterygium were used in this study. Cryopreserved tissue specimens consisting of normal conjunctiva and pterygium were used to study the expression of VEGF and inducible NO synthetase (iNOS), using immunohistochemistry. For confirmation of NOS activity, reduced nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase staining was done. Enzyme-linked immunosorbent assay (ELISA) for detection and quantification of VEGF was performed. RESULTS: Expression of VEGF and iNOS was strongly revealed mainly in the epithelium of the head portions of pterygial specimens, although not in the epithelium of conjunctival ones. Pterygial epithelium was stained with NADPH diaphorase, confirming NOS activity. ELISA showed a greater amount of VEGF in pterygium (11.7 +/- 2.1 pg/mg) compared with normal conjunctiva (4 +/- 0.47 pg/mg) ( p < 0.05). CONCLUSION: These data are the first to demonstrate that VEGF and NO may play an important role in the development of pterygium and to identify VEGF and NO in the epithelium of pterygium. We hypothesize that environmental stress, such as ultraviolet irradiation and local inflammation stimulate the elaboration of NO and VEGF, resulting in the conjunctival fibrovascular ingrowth characteristic of pterygium.

Adult↗

PubMed2001

The thin latissimus dorsi perforator-based free flap for resurfacing.

The authors present their experience with "thin" latissimus dorsi perforator-based free flaps for resurfacing defects. Perforator-based free flaps have been used for various kinds of reconstruction by presenting important donor structures. The thin latissimus dorsi perforatorbased free flap included only the skin and superficial adipose layer to reduce its bulkiness by dissection through the superficial fascial plane. This flap was used in 12 clinical cases, without flap necrosis or other serious postoperative complications. All of the patients were examined by preoperative power Doppler ultrasound in the spectral Doppler mode to search for the most reliable perforator. This noninvasive ultrasound technique determines the exact location and course of and ensures the reliable flow of the perforators; therefore, it greatly assists microsurgeons in saving operation time and in selecting the most suitable design for perforator flap reconstruction. We used perforators that were identified several centimeters from the lateral border of the latissimus dorsi muscle. The thin flap dimensions could be safely designed for flaps measuring up to 20 cm in length and 8 cm in width for primary closure of the donor site. Generally, a long pedicle is not required for resurfacing reconstructions, where small recipient arteries in the bed are acceptable for anastomosis with pedicles. However, pedicle dissection to the proximal vessels through the latissimus dorsi muscle was required when it was necessary to match the recipient vein for anastomosis. The authors conclude that this thin latissimus dorsi perforator-based free flap has great potential for resurfacing because of its constant thickness, easy elevation with the help of power Doppler ultrasound information, and proper flap size for moderate defects caused by scar contracture release, superficial tumor ablation, and so on.

Adolescent↗

PubMed2001

Endoscopically assisted, intraorally approached corrective rhinoplasty.

In the field of facial surgery, operations that require guesswork can result in unexpected complications. One example of such "blind" facial surgery is the lateral osteotomy procedure in corrective rhinoplasty. In most conventional corrective rhinoplasties, the postoperative results of a lateral osteotomy can be controlled by the surgeon's visual perception or manual dexterity; therefore, an experienced surgeon is indispensable in such elaborate operations. Until now, reports have focused on the endoscopic approach through the nasal dorsum or septum through the nostril. However, because of the difficulty in handling the endoscope with osteotomy instruments, it is considered difficult to perform a precise lateral osteotomy procedure using that approach. The authors think the intraoral endoscopic approach should be considered a viable alternative in corrective rhinoplasty. Through small, bilateral gingivobuccal incisions, both the piriform apertures and nasal bones can be easily exposed, and the exact level of the lateral osteotomy can be confirmed directly under the endoscope. The lateral osteotomy is made simply with a reciprocating saw, and symmetrical cutting can be ascertained during the operation. Sometimes, a particular osteotomy level or the proper repositioning of osteotomed segments can be readily evaluated with assistance from the endoscope during the operation. Eleven cases using this procedure were performed over the past 3 years. These endoscopic repairs for a deviated nose were quite helpful for visual confirmation and accurate correction. No complications occurred when using the endoscope with this procedure.

Adult↗

PubMed2001

Cecal rupture by Anoplocephala perfoliata infection in a thoroughbred horse in Seoul Race Park, South Korea.

A 7-year-old Thoroughbred horse was admitted to the Equine Hospital, Korea Racing Association with signs of colic. Based on the size of impactions, the clinical signs, the results of abdominal paracentesis and medical treatment, the prognosis was poor. The horse died 3 hours later following hopeless discharge. At necropsy, the caecum and large colon were fully filled with fecal contents and there was a rupture (10 cm in dia) in the latero- ventral caecum. The mucosa of the ileo-caecal and caeco- colic valves appeared to the hyperemic, edematous and ulcerous. There were many tapeworms in the affected mucosa. Histopathologically, lesions included hyperaemia, a deep necrotic inflammatory lesion and ulcers in the mucosa and submucosa of ileo-caecal and caeco-colic valves. One hundred thirty four faecal samples were obtained from 16 stables and submitted to parasitic examination. A total of 4 genera of eggs were recovered: Stongylus spp (82.1%), Anoplocephala perfoliata (10.5%), Bovicola equi (0.7%) and Parascaris equorum (1.5%). The major findings in this study are the presence of A perfoliata and its suspected association with the colic which led into an eventual caecal rupture. This study indicates the needs for an epidemiological survey of colic that is associated with Anoplocephala.

Animals↗

PubMed2001

Identification of Acanthocephala discovered in changran-pickles and myungran-pickles.

To identify acanthocephala found in 'Changran-pickles' and 'Myungran-pickles' each organ was measured in permanent slides. In the present report, the results obtained were as follows: 1. Morphology of male worms: Worms possessed 18-19 longitudinal rows, with 4 hooks per row, which became smaller towards the base of proboscis. Each worm contained two testis and six cement glands arranged linearly. Body 22.0 by 0.8-0.6 mm and 15.0 by 0.6-0.4 mm, proboscis 284.8 by 227.6 micro m and 524.9 by 151.4 micro m, proboscis sheath 1570.7 by 72.7 micro m and 751.9 by 280.4 micro m, lemnisci length 2566.7 and 1085.6, testis 2202.9-1860.5 by 737.0-575.7 micro m and 1033.8-981.1 by 463.1-351.6 micro m, cement glands 940.2 by 441.2 micro m and 610.0 by 369.1 micro m. 2. Morphology of female worms: Worms possessed 14-18 longitudinal rows, with 6-10 hooks per row and become smaller toward the base of proboscis. Each worm contained an uterine bell and uterus in the posterior portion and the eggs filled the body cavity. Body, approximately 14.0 - 51.0 mm by 0.7-0.5 - 2.2-1.4 mm, proboscis 466.1-268.9 micro m by 259.9-252.0 micro m, proboscis sheath 1550.7-506.0 by 298.8-231.1 micro m, lemnisci length 1325.7-473.1 micro m, eggs approximately 112.4 by 28.5 micro m - 51.7 by 14.0 micro m. In this present study, the acanthocephala collected in 'Changran-pickles' and 'Myungran-pickles' were identified as Echinorhynchus gadi by morphological features.

Acanthocephala↗

PubMed2000

Myositis ossificans of the chest wall simulating malignant neoplasm.

Myositis ossificans originating from the chest wall is extremely rare. We report a case of myositis ossificans occurring in a young woman with progressive painful swelling in the chest wall. Preoperative examination suggested a malignant neoplasm originating from soft tissue. Although rare, myositis ossificans is one of the potential causes of painful swelling in the chest wall, and can be mistaken for a malignant neoplasm.

Adolescent↗

PubMed2000

Different frequencies of electroacupuncture modified the cellular activity of serotonergic neurons in brainstem.

In this study, we evaluated whether different frequencies of electroacupuncture (EA) modified the activities of serotonergic neurons in the dorsal raphe (DR) and raphe magnus (RMg) using double labeling immunohistochemistry for Fos and serotonin. The results demonstrated that both high and low frequency EA increased the colocalization between Fos and serotonin in the DR, not in RMg as compared with anesthesia control. In addition, high frequency EA more potently increased the serotonergic activity in the DR rather than low frequency EA, suggesting that serotonergic pathway from the DR plays an important role in the high frequency EA analgesia.

Animals↗

PubMed2000

Management of persistent or recurrent pneumothorax with a two millimeter mini-videothoracoscope.

The aim of this study was to assess whether a 2 mm mini-videothoracoscope could be used as a conventional videothoracoscope in the management of pneumothorax. Thirty patients of ages from 15 to 35 years with recurrent or persistent pneumothorax were involved in this study. The subjects consisted of 27 males and three females. The indications for videothoracoscopic surgery were ipsilateral recurrent pneumothorax in 12 (40%), persistent air leakage in 15 (50%), visible bullae in 2 (6%), and 1 bilateral pneumothorax (3%). The mean operation time was 42.9+/-12.9 min. The average number of uses for Endo-GIA was 1.9+/-1.3 times and chest tube indwelling time was 3.8+/-2.7 days. The average amount of keptoprofen (100 mg/2 mL/ampule) used on the first postoperative day was 1.2+/-1.1 ampules. No parenteral opioids were given to the patients for pain control after the procedures. After a follow up of 8 to 20 months, there was only one recurrence among the patients. In conclusion, a 2 mm videothoracoscope, in selective cases, can be successfully used as conventional videothoracoscope to manage persistent or recurrent pneumothorax with cosmetically excellent results.

Adolescent↗

PubMed2000

A short history of MADS-box genes in plants.

Evolutionary developmental genetics (evodevotics) is a novel scientific endeavor which assumes that changes in developmental control genes are a major aspect of evolutionary changes in morphology. Understanding the phylogeny of developmental control genes may thus help us to understand the evolution of plant and animal form. The principles of evodevotics are exemplified by outlining the role of MADS-box genes in the evolution of plant reproductive structures. In extant eudicotyledonous flowering plants, MADS-box genes act as homeotic selector genes determining floral organ identity and as floral meristem identity genes. By reviewing current knowledge about MADS-box genes in ferns, gymnosperms and different types of angiosperms, we demonstrate that the phylogeny of MADS-box genes was strongly correlated with the origin and evolution of plant reproductive structures such as ovules and flowers. It seems likely, therefore, that changes in MADS-box gene structure, expression and function have been a major cause for innovations in reproductive development during land plant evolution, such as seed, flower and fruit formation.

Animals↗

PubMed1999

MADS-box genes reveal that gnetophytes are more closely related to conifers than to flowering plants.

The evolutionary origin of the angiosperms (flowering plants sensu stricto) is still enigmatic. Answers to the question of angiosperm origins are intimately connected to the identification of their sister group among extinct and extant taxa. Most phylogenetic analyses based on morphological data agree that among the groups of extant seed plants, the gnetophytes are the sister group of the angiosperms. According to this view, angiosperms and gnetophytes are the only extant members of a clade called "anthophytes" to emphasize their shared possession of flower-like reproductive structures. However, most phylogeny reconstructions based on molecular data so far did not support an anthophyte clade, but also could not clarify the case because support for alternative groupings has been weak or controversial. We have isolated 13 different homologs of MADS-type floral homeotic genes from the gnetophyte Gnetum gnemon. Five of these genes fall into monophyletic gene clades also comprising putatively orthologous genes from flowering plants and conifers, among them orthologs of floral homeotic B and C function genes. Within these clades the Gnetum genes always form distinct subclades together with the respective conifer genes, to the exclusion of the angiosperm genes. This provides strong molecular evidence for a sister-group relationship between gnetophytes and conifers, which is in contradiction to widely accepted interpretations of morphological data for almost a century. Our phylogeny reconstructions and the outcome of expression studies suggest that complex features such as flower-like reproductive structures and double-fertilization arose independently in gnetophytes and angiosperms.

DNA-Binding Proteins↗

PubMed1999

Ligation of Fc gamma RII (CD32) pivotally regulates survival of human eosinophils.

The low-affinity IgG Fc receptor, FcgammaRII (CD32), mediates various effector functions of lymphoid and myeloid cells and is the major IgG Fc receptor expressed by human eosinophils. We investigated whether FcgammaRII regulates both cell survival and death of human eosinophils. When cultured in vitro without growth factors, most eosinophils undergo apoptosis within 96 h. Ligation of FcgammaRII by anti-CD32 mAb in solution inhibited eosinophil apoptosis and prolonged survival in the absence of growth factors. Cross-linking of human IgG bound to FcgammaRII by anti-human IgG Ab or of unoccupied FcgammaRII by aggregated human IgG also prolonged eosinophil survival. The enhanced survival with anti-CD32 mAb was inhibited by anti-granulocyte-macrophage-CSF (GM-CSF) mAb, suggesting that autocrine production of GM-CSF by eosinophils mediated survival. In fact, mRNA for GM-CSF was detected in eosinophils cultured with anti-CD32 mAb. In contrast to mAb or ligands in solution, anti-CD32 mAb or human IgG, when immobilized onto tissue culture plates, facilitated eosinophil cell death even in the presence of IL-5. Cell death induced by these immobilized ligands was accompanied by DNA fragmentation and was inhibited when eosinophil beta2 integrin was blocked by anti-CD18 mAb, suggesting that beta2 integrins play a key role in initiating eosinophil apoptosis. Thus, FcgammaRII may pivotally regulate both survival and death of eosinophils, depending on the manner of receptor ligation and beta2 integrin involvement. Moreover, the FcgammaRII could provide a novel mechanism to control the number of eosinophils at inflammation sites in human diseases.

Antibodies, Monoclonal↗