Biomedical subjects

T H Kim

Publications and source records attributed to T H Kim.

At least 73 records · Page 4Linked to original sources

PubMed2001

A role for mitochondrial Bak in apoptotic response to anticancer drugs.

In the present study a clonal Jurkat cell line deficient in expression of Bak was used to analyze the role of Bak in cytochrome c release from mitochondria. The Bak-deficient T leukemic cells were resistant to apoptosis induced by UV, staurosporin, VP-16, bleomycin, or cisplatin. In contrast to wild type Jurkat cells, these Bak-deficient cells did not respond to UV or treatment with these anticancer drugs by membranous phosphatidylserine exposure, DNA breaks, activation of caspases, or release of mitochondrial cytochrome c. The block in the apoptotic cascade was in the mitochondrial mechanism for cytochrome c release because purified mitochondria from Bak-deficient cells failed to release cytochrome c or apoptosis-inducing factor in response to recombinant Bax or truncated Bid. The resistance of Bak-deficient cells to VP-16 was reversed by transduction of the Bak gene into these cells. Also, the cytochrome c releasing capability of the Bak-deficient mitochondria was restored by insertion of recombinant Bak protein into purified mitochondria. Following mitochondrial localization, low dose recombinant Bak restored the mitochondrial release of cytochrome c in response to Bax; at increased doses it induced cytochrome c release itself. The function of Bak is independent of Bid and Bax because recombinant Bak induced cytochrome c release from mitochondria purified from Bax(-/-), Bid(-/-), or Bid(-/-) Bax(-/-) mice. Together, our findings suggest that Bak plays a key role in the apoptotic machinery of cytochrome c release and thus in the chemoresistance of human T leukemic cells.

Adenoviridae↗

PubMed2001

Sodium nitroprusside enhances TRAIL-induced apoptosis via a mitochondria-dependent pathway in human colorectal carcinoma CX-1 cells.

The tumor necrosis factor-related apoptosis-inducing ligand (TRAIL, Apo-2L) is a recently characterized member of the family of programmed cell death-inducing ligands that includes TNF-alpha and CD95L (FasL). It is well known that TRAIL binds to the death signaling receptors, DR4 and DR5, and initiates the TRAIL death pathway. Activation of this pathway, mediated through a caspase cascade, causes apoptosis. In this study, we hypothesized that oxidative stress facilitates TRAIL-induced apoptosis by promoting caspase activity through cytochrome c release from mitochondria. Human colorectal carcinoma CX-1 cells were treated with various concentrations of TRAIL (12.5-200 ng/ml) and/or sodium nitroprusside (SNP; 0.03-1 mM) for 12 h. SNP, a nitric oxide donor, which had little toxic effect by itself, enhanced TRAIL-induced cytotoxicity. For example, TRAIL-induced apoptosis (200 ng/ml) was increased by a factor of 2.5-fold in the presence of 1 mM SNP. The combined treatment also caused an increase in cytochrome c release, caspase-3 activity, and PARP cleavage. Overexpression of Bcl-2 completely blocked the SNP-promoting effects, but only moderately inhibited TRAIL-induced apoptosis. Similar results were observed in the presence of hydrogen peroxide or peroxynitrite. Taken together, the present studies suggest that SNP enhances TRAIL-induced cytotoxicity by facilitating the mitochondria-mediated caspase signal transduction pathway.

Apoptosis↗

PubMed2001

Mitochondrial dysfunction by gamma-irradiation accompanies the induction of cytochrome P450 2E1 (CYP2E1) in rat liver.

Multiple biological effects are induced by ionizing radiation through dysfunction of cellular organelles, direct interaction with nucleic acids and production of free radical species. The expression of cytochrome P450s was assessed in the livers of 60Co gamma-irradiated rats. Three gray (G) of gamma-irradiation caused CYP2E1 induction with a 3.6-fold increase in the mRNA at 24 h, whereas the expression of CYP1A2 and CYP3A was not changed. Pharmacokinetics of chlorzoxazone, a specific substrate of CYP2E1, was studied in 3 G-irradiated rats. The area under the plasma concentration-time curve from time zero to infinity of 6-hydroxychlorzoxazone and the amount of 6-hydroxychlorzoxazone excreted in 8 h urine were both significantly greater than those in control rats. Hepatic CYP2E1 was not induced in rats exposed to 0.5-1 G of gamma-rays. Rats irradiated at 6-9 G accumulated doses of gamma-rays exhibited smaller increases in the mRNA due to liver injury than those irradiated at a single dose of 3 G gamma-rays. The plasma glucose and insulin levels were not altered in rats with 3 G of gamma-irradiation. As the exposure level of gamma-irradiation increased, the activity of hepatic aconitase, a key enzyme in energy metabolism in mitochondria, was 30-90% decreased. The amount of mitochondrial DNA per gram of wet liver was 50% decreased in rats exposed to 3 G of gamma-rays. These results demonstrated that gamma-ray irradiation at the exposure level inducing organelle dysfunction induced CYP2E1 in the liver, which might be associated with mitochondrial damage, but not with alterations in glucose or insulin levels.

Aconitate Hydratase↗

PubMed2001

Results on preemptive or prophylactic treatment of lamivudine in HBsAg (+) renal allograft recipients: comparison with salvage treatment after hepatic dysfunction with HBV recurrence.

BACKGROUND: Lamivudine has been reported to be able to stabilize liver enzyme and hepatitis B virus (HBV) replication with recurrent hepatitis that has been regarded as a frequent and major risk factor for hepatic dysfunction and chronic liver disease in renal transplant recipients. Because large number of hepatitis antigenemia patients among renal transplant patients experience recurrent hepatic dysfunction with HBV recurrence and permanent histological deterioration, preemptive or primary prophylactic use of lamivudine before transplantation may be more beneficial than a trial for the treatment of advanced hepatic dysfunction. METHODS: We conducted a double arm study to compare the efficacy of lamivudine between the preemptive (HBV DNA positive) or prophylactic (HBV DNA negative) trial for the maintenance of stable liver function (n=10) and the trial for the salvage of advanced hepatic dysfunction developed after renal transplantation (n=6) in hepatitis B viremia carrier renal transplant recipients. RESULTS: Hepatic dysfunction with recurrent HBV antigenemia developed in 11 of 36 (30.6%) hepatitis antigenemia patients with a mean duration of 8.4 months (range 5-19.4 months). In six patients treated with lamivudine after hepatic dysfunction from recurrent hepatitis B viremia, serum AST and ALT level normalized within 1 month and HBV-DNA disappeared in all cases. HBV-DNA, however, reappeared in three (50%) without any discontinuation of lamivudine. Liver biopsy revealed recurrent chronic active hepatitis with severe activity of fibrosis in four cases, cholestatic fibrosing hepatitis in one, and permanent cirrhotic change in one. In seven patients who had preemptive lamivudine treatment at 9, 6, 2, 2, 1, 0, 0 month before the transplantation, HBV-DNA had converted to negative with a mean follow up of 1.2 months (range 1-2 month) in all case. Three patients who had prophylactic trials with lamivudine have all remained HBV-DNA negative. The recurrence rate of HBV viremia in the preemptive or prophylactic lamivudine treated group is 10.0% (1/10), which is significantly lower than that (42.3%, 11/25) in the nonlamivudine-treated group. The re-recurrence rate of HBV viremia was significantly higher (3/6, 50.0%) in the reactive lamivudine treated group than in prophylactic or preemptive group (1/10, 10%). CONCLUSION: Although lamivudine treatment after hepatic dysfunction can be a sound conventional treatment modality, this preliminary study may suggest that preemptive or prophylactic trial of lamivudine before hepatic dysfunction might be a more effective strategy for prevention of permanent histological deterioration and recurrence of hepatitis B viremia.

DNA, Viral↗

PubMed2001

Arabidopsis eIF3e (INT-6) associates with both eIF3c and the COP9 signalosome subunit CSN7.

The Arabidopsis COP9 signalosome is a multisubunit repressor of photomorphogenesis that is conserved among eukaryotes. This complex may have a general role in development. As a step in dissecting the biochemical mode of action of the COP9 signalosome, we determined the sequence of proteins that copurify with this complex. Here we describe the association between components of the COP9 signalosome (CSN1, CSN7, and CSN8) and two subunits of eukaryotic translation initiation factor 3 (eIF3), eIF3e (p48, known also as INT-6) and eIF3c (p105). To obtain a biochemical marker for Arabidopsis eIF3, we cloned the Arabidopsis ortholog of the eIF3 subunit eIF3b (PRT1). eIF3e coimmunoprecipitated with CSN7, and eIF3c coimmunoprecipitated with eIF3e, eIF3b, CSN8, and CSN1. eIF3e directly interacted with CSN7 and eIF3c. However, eIF3e and eIF3b cofractionated by gel filtration chromatography in a complex that was larger than the COP9 signalosome. Whereas eIF3, as detected through eIF3b, localized solely to the cytoplasm, eIF3e, like CSN7, was also found in the nucleus. This suggests that eIF3e and eIF3c are probably components of multiple complexes and that eIF3e and eIF3c associate with subunits of the COP9 signalosome, even though they are not components of the COP9 signalosome core complex. This interaction may allow for translational control by the COP9 signalosome.

Animals↗

PubMed2001

Experimental evaluation of a modified Amplatzer duct occluder.

The purpose of this study was to evaluate a new device specifically designed for patent ductus arteriosus (PDA) occlusion based on PDA anatomy. Percutaneous closure of aortopulmonary shunts was attempted in 10 dogs. Shunts were surgically created in the location and orientation of PDA. The occlusion prosthesis consisted of a cylindrical frame filled with polyester and a 32 degree angled retention disk. The delivery system of the device included a 6 Fr thin-walled Teflon introducing sheath, an antirotating delivery catheter, and cable. Complete occlusion of the shunt was obtained in nine animals. One animal died before device placement. Temporary hemolysis occurred in one dog after device placement. The disk of device was completely covered by smooth glistening neoendothelium at 1-3 months postmortem examination. None of the devices protruded into the lumen of the aorta. The device is an improvement over the standard Amplatzer duct occluder. The angled retention disk lies flatly against the aortic wall, avoiding turbulence or an aortic pressure gradient.

Animals↗

PubMed2001

Effects of peroxisome proliferator-activated receptor-gamma (PPAR-gamma) on the expression of inflammatory cytokines and apoptosis induction in rheumatoid synovial fibroblasts and monocytes.

This study was performed to investigate whether peroxisome proliterator-activated receptor-gamma (PPAR-gamma) exerted an anti-inflammatory effect on rheumatoid synovial cells and inhibited dysregulated proliferation. The expression of PPAR-gamma mRNA in cultured human synoviocytes and THP-1 cells was analysed by RT-PCR. PPAR-gamma was expressed in normal, osteoarthritis (OA), rheumatoid arthritis (RA) synovial cells as well as a human monocytic cell line, THP-1. In RA and OA synoviocytes, the induction of inflammatory cytokine mRNA expression such as TNF-alpha and IL-1beta was significantly inhibited by the natural PPAR-gamma agonist, 15 deoxy-Delta(12,14)prostaglandin J(2)(15d-PGJ(2)). The effect of PPAR-gamma on the nuclear factor (NF)-kappaB activity was tested by electrophoretic mobility shift assay (EMSA). Both troglitazone and 15d-PGJ(2)markedly inhibited TNF-alpha-induced NF-kappaB activation at 30 microM. However, PPAR-gamma agonist neither reduced proliferation nor induced apoptosis in RA synoviocytes when measured by XTT assay and fluorescence activated cell sorter (FACS) analysis. In contrast, it induced apoptosis in a dose-dependent manner in THP-1 cells and augmented TNF-related apoptosis-inducing ligand (TRAIL)-induced apoptosis as well. In conclusion, these data demonstrate that PPAR-gamma is expressed in human synoviocytes and THP-1 cells, and the PPAR-gamma activation inhibits expression of inflammatory cytokines in RA synoviocytes. Furthermore, PPAR-gamma activation induces apoptosis by itself and augments TRAIL/Apo2L-induced apoptosis in THP-1 cells. These results suggest that PPAR-gamma agonists may provide a new therapeutic approach for RA.

Apoptosis↗

PubMed2001

Reconstruction of basement membrane in skin equivalent; role of laminin-1.

To reconstruct the basement membrane in a skin equivalent, the epidermodermal interface was coated with porcine type IV collagen and mouse laminin-1 at various ratios before keratinocyte seeding. Laminin-1, a component of the basement membrane, induced massive infiltration of keratinocytes into the dermal equivalent, while type IV collagen induced discrete demarcation between dermal and epidermal compartments without any infiltrating cells. Immunohistochemical staining indicated that the laminin-induced infiltrating cells expressed endogenous type IV collagens at the cell periphery, which were not incorporated into the basement membrane structure. The infiltrating cells did not express fibronectin receptor alpha5beta1 integrin but showed MMP-9 secretion and cell surface associated MMP-2. However, when laminin-1 was preincubated with type IV collagen, laminin-1-induced keratinocyte infiltration as well as MMP-9 induction were almost completely suppressed to basal levels. Therefore, replenishment of the type IV collagen lattice seemed to cause laminin-stimulated cells to anchor to the lattice, in a similar manner to the basal cells on the basement membrane of normal skin. Our study suggests that the molar ratio of basement membrane components may determine the behavior of basal cells within the wound healing microenvironment, which is probably regulated either by extracellular matrix deposition or degradation.

3T3 Cells↗

PubMed2001

Radiologic changes of cervical spine in ankylosing spondylitis.

Ankylosing spondylitis (AS) is characterised by its effects on the axial skeleton. The cervical spine is also vulnerable to the disease process. Our aim was to determine the frequency of radiologic changes to the cervical spine and their correlation with clinical variables. We also used the Bath Ankylosing Spondylitis Radiology Index (BASRI) system, which is one of the reliable scoring systems of radiography, to score the global radiologic changes to the cervical and lumbar spine and the hip joints in our AS cohort. There were 181 patients with anteroposterior and lateral full-flexion views on radiography of the cervical spine here included in the study. A radiologist examined the radiologic changes to all anatomical compartments of the cervical spine in detail and graded them according to the BASRI system. We used the clinical and demographic data of our AS cohort to determine their relation to the radiographic changes. Eighty-eight patients (48.6%) showed radiological changes to the cervical spine; to the discovertebral joint 35.9%; the apophyseal joint 26.0%; atlantoaxial articulation 22.1% (atlantoaxial subluxation 13.8%); the costovertebral joint 18.2%; and to the posterior ligamentous attachment 11.6%. Using the BASRI system, 73 patients (40.3%) showed radiologic changes to the cervical spine and were graded as score 1 (1.7%), 2 (22.7%), 3 (6.6%) or 4 (9.4%). Among those graded as normal by the BASRI system, 17 showed some changes the cervical spine, such as atlantoaxial joint subluxation or narrowing, and severe osteoporosis with no other radiographic changes. Current age, disease duration, inflammatory back pain and cervical symptoms were associated with the radiographic changes to the cervical spine. The BASRI-cervical spine score correlated with the BASRI-lumbar spine and hip joint score, sacroiliitis, disease duration, and duration of inflammatory back pain and cervical symptoms. Our data suggest that radiographic changes to the cervical spine are frequent in AS, and can be predicted in the patients with old age, long duration of disease and inflammatory back pain, and cervical symptoms. Also, the BASRI scoring system showed similar results as a detailed assessment of the cervical spine in our study.

Adolescent↗

PubMed2001

Induction of remission with intravenous immunoglobulin and cyclophosphamide in steroid-resistant Evans' syndrome associated with dermatomyositis.

Evans' syndrome is characterised by the simultaneous or sequential occurrence of Coombs'-positive haemolytic anaemia (AIHA) and immune thrombocytopenia without underlying aetiology. It has been found to be associated with collagen vascular diseases, especially systemic lupus erythematosus (SLE) and scleroderma. However, Evans' syndrome with dermatomyositis is very rare. A 59-year-old woman, who had been taking high-dose prednisolone for a month and cyclosporin for 10 days for dermatomyositis, developed purpura on the left popliteal fossa. The platelet and haemoglobin levels decreased to 77,000/mm3 and 9.8 g/dl, respectively. Antiplatelet antibody was positive. Thrombocytopenia responded to intravenous immunoglobulin (IVIG) for a short time, but further decreased in a week. Her blood film showed features of haemolytic anaemia. Laboratory findings showed reticulocytosis and a positive direct Coombs' test. Bone marrow examination showed a mild hyperplasia of erythroid precursors and megakaryocytes. The patient was successfully treated with cyclophosphamide in addition to oral prednisolone. AIHA in connective tissue disease may develop gradually and show a benign clinical course in most patients. Therefore, we suggest that patients with dermatomyositis and anaemia should always be checked for haemolysis if there is no other explanation.

Anemia, Hemolytic, Autoimmune↗

PubMed2001

Isolation of neuronal precursors from differentiating P19 embryonal carcinoma cells by neuronal T alpha 1-promoter-driven GFP.

The induction of pluripotent P19 embryonal carcinoma (EC) cells with retinoic acid results in their differentiation into cells that resemble neurons, glia, and fibroblasts. To isolate and enrich the developing neurons from heterogeneously differentiating P19 EC cells, we used a recently introduced protocol combining the expression of green fluorescent protein (GFP) driven by a tissue-specific promoter and fluorescence-activated cell sorting. Cells were transfected with the gene for GFP, which is under the control of the neuronal T alpha 1 tubulin promoter. After four days of retinoic acid treatment, GFP was specifically detected in cells undergoing neuronal differentiation. Sorting of fluorescent differentiating P19 EC transfectants yielded populations highly enriched in neuronal precursors and neurons. Immunoreactivity for nestin and neurofilament was observed in 80 and 25% of the sorted cell population, respectively. These results demonstrate that differentiated neuronal precursor cells can be efficiently isolated from differentiating pluripotent embryonic cells in vitro, suggesting that this method can reproducibly provide homogeneous materials for further studies on neurogenesis.

Antineoplastic Agents↗

PubMed2001

Covered retrievable tracheobronchial hinged stent: an experimental study in dogs.

PURPOSE: To evaluate the safety and technical feasibility of the use of a covered retrievable tracheobronchial hinged stent and investigate the histopathologic airway changes after placement and removal of the stent in dogs. MATERIALS AND METHODS: The experimental stent was composed of tracheal and bronchial stents that were connected together at their ends. Each stent was woven from a single thread of 0.2-mm-diameter nitinol wire filament in a tubular configuration and covered with polyurethane solution by a dipping method. Drawstrings were attached at the upper end of the tracheal stent for stent removal. Under fluoroscopic guidance, 20 stents were placed at the lower trachea and left main bronchus in 20 dogs and were electively removed 4 weeks (n = 10) or 8 weeks (n = 10) after placement. Ten dogs were killed just after stent removal and the remaining 10 were killed 2 weeks after stent removal. RESULT: Stents were successfully placed in all dogs. Pneumonia was observed in three dogs. Stent migration occurred in seven dogs (35%). Except for two cases of stent expectoration, 18 stents were easily removed within a few minutes. There was considerable granulation tissue proliferation and inflammatory reaction in the airways of the dogs that were killed just after stent removal. The pathologic changes of the airways returned to almost-normal conditions 2 weeks after stent removal. CONCLUSION: Placement and removal of a covered retrievable tracheobronchial hinged stent seems to be feasible, and histopathologic changes of the airway related to the stents returned to normal 2 weeks after stent removal.

Animals↗

PubMed2001

Pefloxacin and ciprofloxacin increase UVA-induced edema and immune suppression.

BACKGROUND: Quinolone antibiotics are popularly prescribed antibiotics because of their wide antibacterial spectrum and lowered bacterial resistance. Quinolone antibiotics are one of the well-known photosensitizers that induce phototoxicity. Their role in photocarcinogenesis has been suggested in some studies. MATERIAL AND METHODS: Mice were treated with two quinolone antibiotics (ciprofloxacin, which is less phototoxic, and pefloxacin, which is more phototoxic) to study the effect of the antibiotics on sunburn and immune suppression by ultraviolet A (UVA) irradiation. The effects of a combined treatment with UVA and these quinolone antibiotics were measured on back skin swellings, sunburn cell formations, depletion of epidermal Langerhans cells, and local and systemic suppression of contact hypersensitivity. RESULTS: Mice treated with both UVA and quinolone showed significantly increased back skin swellings and decreased epidermal Langerhans cells than mice treated with UVA only. Sunburn cells were increased significantly in mice treated with pefloxacin and 50 J/cm2 of UVA. Combination of pefloxacin and UVA suppressed local contact hypersensitivity significantly, but not systemic contact hypersensitivity. CONCLUSION: Phototoxic quinolones augmented the effect of UVA by increasing sunburn and apoptosis, depleting Langerhans cells and suppressing local immune response. By affecting apoptosis and immune suppression, they may facilitate photocarcinogenesis caused by UVA.

Animals↗

PubMed2001

The effects of topical alpha-hydroxyacids on the normal skin barrier of hairless mice.

BACKGROUND: alpha-hydroxyacids (AHA), such as glycolic acid and lactic acid, have recently been used in cosmetic and dermatological formulations. However, the mechanisms of action of these substances have not been well documented. OBJECTIVES: This study was done to investigate the effects of AHA on the skin barrier of hairless mice and to clarify the contribution of AHA to the formation and secretion of the lamellar bodies (LB), which are known to be the critical structure for barrier function in the epidermis. METHODS: 5% Lactic acid and 5% glycolic acid were applied to normal skin of the mice daily for 14 days. RESULTS: Changes in transepidermal water loss (TEWL), capacitance and electron microscopic findings of the epidermis of hairless mice were compared with those in which only the vehicle was applied. CONCLUSIONS: There were no significant differences in TEWL, capacitance or epidermal thickness between the epidermis of the mice to which AHA or vehicle only had been applied. On electron micrographs, the normal epidermis to which AHA had been applied showed an increase in the number and secretion of LB and a decrease in the number of stratum corneum (SC) layers in comparison with the epidermis to which the vehicle only had been applied. The lipid layers of the SC intercellular spaces and calcium gradient in both the epidermis with application of AHA and that with vehicle only were normal. These results suggest that AHA, in low concentration (5%), may improve the skin barrier in hairless mice by inducing enhanced desquamation, and by increasing the number and secretion of LB without increasing TEWL.

Animals↗

PubMed2001

Epidermal grafting after chemical epilation in the treatment of vitiligo.

BACKGROUND: Vitiligo on hairy areas like the scalp and eyebrows is frequently associated with leukotrichia and repigmentation by photochemotherapy is usually difficult because of a deficient melanocyte reservoir. Although epidermal grafting to supply melanocytes is very effective for stable vitiligo, hair growth inhibits successful transfer of melanocytes from grafted epidermis in dense hair-bearing regions. OBJECTIVE: To investigate the effectiveness of preoperative chemical epilation to improve the results of epidermal graft by suction blister on hairy areas. METHODS: Two patients who had vitiligo with leukotrichia on the face and scalp were treated with epidermal grafting using suction blister after chemical epilation. Two weeks after the graft they were treated with topical psolaren plus ultraviolet A (PUVA) therapy. RESULTS: Epidermal grafting was performed successfully, and successful repigmentation of the skin with significant improvement of leukotrichia was observed in each of two patients. CONCLUSION: Chemical epilation followed by epidermal grafting is a safe, easy, and effective treatment for vitiligo affecting hairy regions.

Adult↗

PubMed2001

Cross-cultural adaptation and validation of Korean Western Ontario and McMaster Universities (WOMAC) and Lequesne osteoarthritis indices for clinical research.

OBJECTIVE: Our aims were to translate WOMAC and Lequesne osteoarthritis (OA) indices into Korean (KWOMAC, KLequesne) and confirm their reliability, validity, and responsiveness. DESIGN: The WOMAC and Lequesne indices were translated into Korean by three translators and translated back into English by three different translators. Fifty consecutive patients with OA were asked to rate the comprehensibility of the questions on a 4-point scale. The comprehensibility (responding with 'good' and 'very good') ranged from 78% to 99%. Test-retest was performed in another 47 patients with knee OA. The final 53 patients with knee OA, within the context of a clinical trial of two non-steroidal antiinflammatory drugs for 4 weeks, were studied to assess the internal consistency, construct validity, and responsiveness of the Korean versions. RESULTS: The test-retest reliability of the KWOMAC 3 subscales and the KLequesne yielded intraclass correlation coefficients of 0.79-0.89 and 0.87. The Cronbach standardized alphas were 0.81-0.96 and 0.75, respectively. For the construct validity, the correlation coefficients of both the KWOMAC subscales and the KLequesne with patient pain assessment and patient global assessment were between 0.30 and 0.70 and the KWOMAC subscales correlated with the KLequesne (0.41-0.55). For responsiveness, the KWOMAC and KLequesne scores significantly improved by 4-week post-treatment compared with pre-treatment; effect size values were between 0.41 and 0.69 for the KWOMAC subscales and 0.70 for the KLequesne; and the relative efficiency values of the KWOMAC subscales vs the KLequesne were between 0.87 and 0.90. CONCLUSIONS: The reliability, validity, and responsiveness of the KWOMAC and the KLequesne are confirmed.

Adult↗

PubMed2001

Analysis of radiation workers' dose records in the Korean National Dose Registry.

Data are presented on the externally received personal dose equivalent for radiation workers who used the Korea Radioisotope Association's personal monitoring and dose record keeping service since 1984, and provide initial statistics on Korean workers who have been exposed to ionising radiation in different occupations. The total number of workers registered during the period of 1984 to 1999 was 64,518. The number increased steadily and the accumulated dose also increased. The proportion of radiation workers by occupation was 38.4% for nuclear power plants, 20.3% for industrial organisations and 12.4% for non-destructive industry. The annual collective dose of radiation workers was 31.72 man.Sv in 1999. The mean annual dose by sex was 1.49 mSv for males and 0.56 mSv for females and the mean annual dose for a worker was 1.41 mSv with the highest mean dose being received by non-destructive industry (3.53 mSv). Very few workers (0.8%) received more than 20 mSv (2 rem) and only one more than 50 mSv, the legal limit for an annual dose increase. There has been a steady decline in the mean dose since 1984, showing a significant decrease in dose with time (p<0.001). The data showed that radiation protection in Korea was improving, though annual doses were still higher than other countries.

Adolescent↗

PubMed2001

The role of gastrointestinal endoscopy in long-distance runners with gastrointestinal symptoms.

BACKGROUND: Exercise-related gastrointestinal symptoms are not uncommon among athletes. The occurrence of gastrointestinal bleeding has been reported, especially in long-distance runners. We studied gastrointestinal mucosal damage, using gastrointestinal endoscopy, in competitive long-distance runners. Gastrointestinal blood loss and anaemia before and after running were also assessed. METHODS: Sixteen competitive long-distance runners (all men; age range 16-19 years) participated in the study. All runners completed a symptom questionnaire prior to a 20 km race. Stool occult blood and haematological studies (haemoglobin, haematocrit, serum iron, total iron-binding capacity [TIBC] and ferritin) were performed before and immediately after the race. Gastrointestinal endoscopy was performed to assess macroscopic changes. Colonoscopy was also performed on the patients who had positive stool occult blood before or after the race. RESULTS: Gastrointestinal symptoms were frequently experienced by the runners. Gastritis (n = 16), oesophagitis (n = 6) and gastric ulcer (n = 1) were found at gastroscopy. Colonoscopy was performed on four patients who had positive stool occult blood. One had multiple erosions at the splenic flexure and one had a rectal polyp. Five runners had anaemia, and all of these had at least one endoscopic lesion (three gastritis, two oesophagitis and one multiple erosion at the splenic flexure). There were significant changes in the following haematological parameters after the race: iron (decreased, P = 0.02), ferritin (decreased, P = 0.001) and TIBC (increased, P = 0.00005). CONCLUSIONS: Gastrointestinal symptoms and gastrointestinal mucosal damage are prevalent among long-distance runners. Prior to treatment, gastrointestinal endoscopy should be considered in long-distance runners with gastrointestinal symptoms and/or anaemia.

Adolescent↗