Biomedical subjects

D S Han

Publications and source records attributed to D S Han.

At least 55 records · Page 3Linked to original sources

PubMed1998

Interleukin-1 beta, -6 and interferon-gamma productions in patients undergoing continuous ambulatory peritoneal dialysis.

In order to investigate cytokine productions in patients undergoing continuous ambulatory peritoneal dialysis (CAPD), we studied the production of interleukin (IL)-1 beta, -6 and interferon (IFN)-gamma by cultured peripheral blood mononuclear cells (PBMC) in peritonitis-free CAPD patients. The correlation of cytokine production with plasma parathyroid hormone (PTH) and albumin levels was also evaluated. While the release of IL-1 beta was not markedly different from controls release of IL-6 from 24-hour cultured PBMCs was significantly greater than that of controls, (Mean +/- S.D., IL-6: 2186.8 +/- 1217.9 pg/ml, vs 1516.3 +/- 767.9, p < 0.05). The addition of lipopolysaccharide (LPS, 10 micrograms/ml, significantly stimulated IL-1 beta and -6 production of PBMCs in CAPD patients and controls, compared to an unstimulated condition. The LPS-induced IL-1 beta production was also not markedly different from controls, whereas LPS-induced IL-6 production was significantly higher than controls (IL-6: 13,220.7 +/- 7177.4 vs 7411.4 +/- 1236.9, p < 0.05). However, the percentage increases of IL-6 production stimulated with LPS in CAPD patients were not significantly different from controls (p > 0.05). No difference of baseline IFN-gamma was detected between CAPD patients controls, but phytohemagglutinin (PHA, 10 micrograms/ml)-stimulated IFN-gamma release was significantly higher in CAPD patients than controls (2425.9 +/- 1565.0 pg/ml vs 1364.0 +/- 755.1, p < 0.05). There was no significant correlation between PTH and, IL-1 beta, serum albumin level and LPS-stimulated IL-6 production (r = 0.54, p < 0.05). In conclusion, CAPD seems to partly induce activation of PBMCs with an enhanced release of IL-6 and IFN-gamma, and CAPD patients with higher serum albumin levels tend to show higher IL-6 production in immune response.

Adult↗

PubMed1998

A case of Behçet's syndrome with supeior vena cava syndrome.

Behçet's syndrome is a multi-systemic and chronic disorder that affects many organs. It has been suggested that the diagnosis was based on the presence of the 'major' and 'minor' clinical criteria. When thromobophlebitis, arthritis, central nervous system or gastrointestinal lesions are also present. Behçet's syndrome will be thought to be present in the appropriate geographic area. We report a case of superior vena cava syndrome caused by Behçet's disease in a 40-year-old man with recurrent oral aphthous ulcers and skin rashes on the anterior chest wall. There were multiple thrombosis of the superior vena cava, innominate and subclavian veins. This patient also had a solitary cecal ulcer with an ileocecal fistula and downhill varix. The chest CT, veno-cavography, pulmonary angiography and colon study were taken and follow-up was performed.

Adult↗

PubMed1998

Is kidney graft biopsy indicated in recipients with newly developed, microscopic hematuria?

We actively performed renal allograft biopsies on 87 living donor renal transplant recipients presenting with stable serum creatinine but showing newly developed recurrent microscopic hematuria with a small amount of proteinuria during the maintenance phase of immunosuppression and found definite pathological lesions in 56 cases (64%). Chronic rejection of a mild grade (n = 27) and various kinds of glomerulonephritis (n = 27) were the major pathological diagnoses, and from 14 cases singular or complicated cyclosporine (CsA) toxicity was found. Twenty-four out of the 27 glomerulonephritis cases were IgA nephropathy, which is the most common glomerulonephritis in Korea. Through this study, the authors found chronic rejection or glomerulonephritis even in grafts which are generally considered to be normal. CsA nephrotoxicity, which was not expected clinically, could be found. In summary, renal allograft biopsy on patients, even with stable graft function when they start to show microscopic hematuria with or without a small amount of proteinuria, should be performed to document the early intragraft events if there are no medical contraindications.

Adult↗

PubMed1997

Post-transplantation diabetes is better controlled after conversion from prednisone to deflazacort: a prospective trial in renal transplants.

It is well known that long-term use of steroids plays a decisive role in the development of glucose intolerance and diabetes mellitus (DM). Deflazacort, an oxazoline derivative of prednisolone, has been introduced as a potential substitute for conventional steroids in order to ameliorate glucose intolerance. We initiated a randomized study of conversion from prednisone to deflazacort in kidney transplantation (Tx) recipients presenting with pre-Tx or post-Tx DM to ascertain whether or not the switch to deflazacort would ameliorate the diabetic state. Forty-two recipients in the conversion group were compared with 40 patients on prednisone (the control group) in a prospective manner. The dose reduction of insulin or oral blood glucose-lowering agents, the adequacy of glucose control, and the development of side effects were the criteria for evaluating outcome. In the conversion group, patients were switched to a deflazacort at a dose ratio of 6 mg deflazacort to 5 mg prednisone. During the mean follow-up period of 13.2 months, neither graft dysfunction nor acute rejection developed in the conversion group. Improvement in blood glucose control in the conversion group was noted. When the conversion group was stratified into pre- or post-Tx DM, promising effects were clearly evident in the post-Tx DM patients. More than 50% dose reduction of blood glucose-lowering agents was possible in 42.3% of post-Tx DM patients. In conclusion, it was readily possible to control blood glucose better in post-Tx DM recipients without seriously affecting the immunosuppressive activity after conversion to deflazacort.

Adult↗

PubMed1997

Extrarenal manifestations of autosomal dominant polycystic kidney disease.

Recently, with the widespread use of new imaging techniques, the diagnosis of autosomal dominant polycystic kidney disease (ADPKD) is increasing. To analyze the extrarenal manifestations of ADPKD in Korean patients, we retrospectively studied the clinical characteristics of 30 patients with ADPKD. Thirty Patients with ADPKD who had been diagnosed at Yongdong Severance Hospital from 1988 through 1994 were recruited for this study. All patients' past and family histories were re-evaluated, and charts and radiologic images were reviewed retrospectively. The male to female ratio was 9:21, and the age of initial diagnosis was 39.2 +/- 13.8 (mean +/- SD) years. In 15 cases (50%), ADPKD had been diagnosed by renal symptoms; in 8 cases (26.7%), by chance during evaluation of extrarenal diseases; in 5 cases (16.7%), by family screening; and in 2 cases (6.7%), by uremic symptoms. Extrarenal involvement included hepatic cysts (70%), pancreatic cysts (16.7%), splenic cysts (6.7%), thyroid cysts (6.7%), inguinal hernia (3.3%), and colonic diverticula (3.3%). In 5 cases (16.7%), cardiac valvular abnormalities were noted by echocardiography. Seven patients underwent hemodialysis, and the duration from the initial diagnosis to initiation of dialysis was 9.9 +/- 8.5 (mean +/- SD) years. We investigated the extrarenal manifestations of 30 cases of ADPKD in Koreans, which were also common and clinically important as renal manifestations. Renal cysts are only one of a myriad of renal and extrarenal manifestations of ADPKD. ADPKD should be managed systematically since this disorder is a systemic disease with clinically important involvement of the cardiovascular system, the gastrointestinal tract, the genitourinary system, and the musculoskeletal system.

Adolescent↗

PubMed1997

The effect of anti-hypertensive drugs on DNA synthesis and proliferation of cultured rat aortic smooth muscle cells.

The aim of this study was to elucidate the effects of anti-hypertensive drugs, nifedipine, furosemide, hydrochlorothiazide, captopril, and atenolol on DNA synthesis and proliferation of cultured rat aortic smooth muscle cells induced by fetal calf serum. Aortic smooth muscle cells from Sprague-Dawley rats were isolated, cultured, and seeded in multi-well plates. When confluent, cells were cultured in a conditioned medium without fetal calf serum. After 72 hours, cells were cultured in the medium retaining 10% fetal calf serum with or without anti-hypertensive drugs by increasing the concentration between 10(-8) and 10(-4) M. DNA synthesis was assessed by [3H]-thymidine uptake and proliferation by cell numbers using a hemocytometer. Nifedipine at a concentration of 10(-5) M and 5 x 10(-5) M inhibited serum-induced DNA synthesis significantly by 50.8% and 86.6%, respectively (p < 0.05). The results of cell numbers paralleled those of 3H-thymidine incorporation. Serum-induced DNA synthesis was also reduced by 32.6% at the highest dose of furosemide (10(-4) M), but there was no statistical significance. Hydrochlorothiazide, captopril, and atenolol did not show anti-proliferative effect throughout any of the doses. In conclusion, among the various anti-hypertensive drugs, nifedipine seems to be most beneficial in view of its direct inhibitory effect on DNA synthesis and proliferation of smooth muscle cells, as well as for its anti-hypertensive effect.

Animals↗

PubMed1997

Acute pyelonephritis focusing on perfusion defects on contrast enhanced computerized tomography(CT) scans and its clinical outcome.

OBJECTIVES: Many cases of acute pyelonephritis show renal perfusion defects on contrast enhanced computerized tomography (CT) imaging studies. The purpose of this study is to show the frequency of renal perfusion defects in uncomplicated acute pyelonephritis and to compare the clinical responses of patients who had perfusion defects or not. METHODS: We studied patients who had symptoms and signs of acute pyelonephritis through CT examinations with contrast enhancement. We identified 21 cases who had perfusion defects among 35 patients who had undergone CT imaging studies and compared the clinical data in the two groups of patients who had perfusion defects on CT (group 1) and who had not (group 2). RESULTS: Nearly all patients had typical symptoms and signs of acute pyelonephritis such as high fever and chill, flank pain and costovertebral angle tenderness. Combined clinical problems were septic shock (one case, 4.8%) and disseminated intravascular coagulation (DIC) (one case, 4.8%) in group 1. Laboratory findings were not different between the two groups. All patients were treated with antibiotics and had successful recoveries. The duration of recovery of pyuria in group 1 (5.2 +/- 9.6 days) was not longer than that in group 2 (3.1 +/- 2.9 days) (p > 0.05). The length of defeverscence in group 1 (7.0 +/- 4.6 days) was longer than in group 2 (3.5 +/- 2.7 days) (p < 0.05). There were no differences between group 1 and group 2 in the rate of predisposing factors. Thirteen of 21 cases (61.9%) in group 1 and five of 14 cases (35.7%) in group 2 had positive urine culture results which are relatively low probably due to the administration of antibiotics prior to our emergency room visit. Perfusion defects on CT were very frequent findings (60.0% of the clinical acute pyelonephritis patients). We classified CT findings of group 1 as focal unilateral (2 cases, 9.5%), multifocal unilateral (14 cases, 66.7%) and multifocal bilateral (5 cases, 23.8%), and there were no differences between the subgroups of group 1 in the duration of defeverscence. CONCLUSION: Those patients who had perfusion defects on CT showed relatively severe clinical courses but responses to early antibiotics were very good. Contrast enhanced CT scans may be very sensitive for the detection of acute renal parenchymal inflammatory disease and for defining the extent of disease, but it is clinically not essential to perform in the early uncomplicated acute pyelonephritis because CT diagnosis does not change management. Clinical use of contrast enhanced CT scan may be appropriate in case of persistence of fever and leukocytosis for more than seven days despite antibiotic treatment.

Acute Disease↗

PubMed1997

Impact of metabolic acidosis on serum albumin and other nutritional parameters in long-term CAPD patients.

To evaluate the effects of metabolic acidosis on serum albumin and other nutritional parameters in long-term continuous ambulatory peritoneal dialysis (CAPD) patients, we undertook a retrospective study involving 106 CAPD patients who had monthly biochemical measurements and urea kinetic studies every 6 months for more than 2 years. The patients were divided into three groups according to their mean total CO2 (tCO2) level of the 2-year follow-up (Group I: mean tCO2 < 22 mmol/L; Group II: 22 mmol/L < or = tCO2 < 26 mmol/L; Group III: mean tCO2 > or = 26 mmol/L), and the clinical, biochemical, and urea kinetic data were compared between the three groups. The mean tCO2 in Groups I, II, and III were 20.62 +/- 1.2 mmol/L, 23.91 +/- 1.1 mmol/L, and 27.3 +/- 0.8 mmol/L, respectively. The percentage of body weight (Bwt) to ideal body weight (IBW) was significantly higher in Group I (113.1 +/- 15.3%) compared to Group II (103.5 +/- 11.5%) and Group III (98.7 +/- 8.0%) (p < 0.05), but the percentage of lean body mass (LBM) to Bwt was not different between the three groups. Compared to Group III, Group I had significantly higher blood urea nitrogen (BUN) (61.1 +/- 14.3 vs 46.1 +/- 7.2 mg/dL, p < 0.05), serum albumin (4.04 +/- 0.31 vs 3.75 +/- 0.39 g/dL, p < 0.05), and normalized protein equivalent to nitrogen appearance (NPNA) (1.02 +/- 0.21 vs 0.88 +/- 0.14 g/kg/day, p < 0.05), and more ultrafiltration volume (1.4 +/- 0.4 vs 1.0 +/- 0.3 L/day, p < 0.05), in spite of comparable dialysis dose and albumin loss into the dialysate. No differences were observed in the three groups in the changes of tCO2, Bwt/IBW, LBM/Bwt, BUN, and albumin from the baseline values after the 2-year follow-up. Using stepwise multiple regression analysis, NPNA, Bwt/IBW, and ultrafiltration volume were independent factors affecting mean tCO2 level. In conclusion, low tCO2 levels in long-term CAPD patients may reflect increased protein intake, and the mild to moderate degrees of metabolic acidosis may not affect the nutritional status of well-dialyzed CAPD patients.

Acidosis↗

PubMed1997

Results of kidney transplantation from 1979 to 1997 at Yonsei University.

1. Long-term graft survival markedly improved after the introduction of CsA as the main immunosuppressant in living-donor kidney transplantation at our institution. 2. HLA-identical LRD kidney transplantation provided the best long-term graft survival rate, probably due to a decreased incidence of graft loss from rejection. 3. We could achieve good long-term graft survival in LURD kidney transplantation compared with that of HLA-haploidentical LRD kidney transplantation. 4. Because of the striking discrepancy between organ donation and the increasing demand for transplantation, distant relative donors and LURDs, including swap donors, should be considered as an alternative way to increase the number of available donors when accompanied by a careful evaluation process.

Adolescent↗

PubMed1996

The effects of high glucose concentration on angiotensin II- or transforming growth factor-beta-induced DNA synthesis, hypertrophy and collagen synthesis in cultured rat mesangial cells.

Hyperglycemia is a principal characteristic of diabetes, and has an influence on many cellular functions. In order to investigate whether the intracellular signaling pathways inducing proliferation, hypertrophy and matrix synthesis of mesangial cells are altered in a diabetic environment, we evaluated the effects of a high concentration of extracellular glucose(25 mM; 450 mg/dl) on [3H]thymidine uptake, hypertrophy, and [3H]proline incorporation into a collagenase-sensitive protein, induced by angiotensin II(Ang II) or transforming growth factor(TGF)-beta, in cultured rat mesangial cells. The exposure to a high glucose concentration for 7 days significantly inhibited Ang II(10(-6) M)-induced [3H]thymidine uptake, compared to normal glucose concentration (5 mM)(M +/- SD., 1050 +/- 100 cpm/well vs 550 +/- 97, p < 0.05), and markedly prevented the inhibition of [3H]thymidine uptake by TGF-beta(1 ng/ml)(132 +/- 10 vs 340 +/- 67, p < 0.05). The administration of H-7(50 microM), a protein kinase C(PKC) inhibitor, did not reverse these effects of high glucose on [3H]thymidine uptake. On flow cytometric analysis of cell size, the mean cell size was significantly greater for the cells exposed to high glucose or treated with Ang II or TGF-beta, compared to that for the untreated cells. But the addition of Ang II or TGF-beta to the cells exposed to high glucose did not show further enlargement in size. The exposure to high glucose and the treatment with Ang II or TGF-beta significantly increased collagen synthesis, measured by [3H]proline incorporation. The Ang II -or TGF-beta-induced increase of [3H]proline incorporation did not show changes under high glucose culture condition, compared to normal glucose concentration(Ang II, 27880 +/- 3560 cpm vs 26978 +/- 2284, TGF-beta, 26559 +/- 3700 vs 25800 +/- 1660, p > 0.05). In conclusion, although the signaling pathway for DNA synthesis by Ang II or TGF-beta are influenced, possibly mediated by PKC-independent mechanism(s), the pathway inducing hypertrophy or collagen synthesis by both agents appears to be unchanged under the high extracellular glucose concentration in cultured rat mesangial cells.

Angiotensin II↗

PubMed1996

Studies on bone markers and bone mineral density in patients with chronic renal failure.

Renal osteodystrophy has become a frequent complication in patients with chronic renal failure (CRF), and various histologic forms such as high turnover, low turnover and mixed bone disease have been demonstrated. The only reliable method for distinguishing patients with high turnover from those with low turnover bone disease is bone histomorphometric study, but its clinical utility is restricted. Because of its invasive nature, efforts have been made to predict indirectly the type and severity of this metabolic bone disease by serum assays. In this cross-sectional study, we measured total and regional (head, arms, trunk, ribs, legs, spine and pelvis) bone mineral densities (BMD) by dual X-ray absorptiometry (DXA) in patients with variable degrees of CRF and correlated them with various bone markers. Decreased BMDs were detected in various skeletal sites (trunk and pelvis) in the patients' group. Total BMD Z score was lower in predialysis CRF patients than in the control subjects. Decreased BMD Z scores on weight-bearing bone were pronounced at L1 lumbar vertebra, femur trochanter, femur neck and Ward's triangle. Positive linear correlations were found between creatinine clearance and trunk, ribs, pelvis, and spine BMDs. There were inverse linear correlations between total BMD and total BMD Z score and alkaline phosphatase (AP), urine deoxypyridinoline (U-DPD) in the patients' group. There were no correlations between regional and total BMD, total BMD Z score and serum calcium, ionized calcium, and serum phosphate. There were inverse linear correlations between BUN, creatinine and bone-specific alkaline phosphatase in the predialysis CRF group. We evaluated the correlations between intact parathyroid hormone (i-PTH) and biochemical and other bone markers. There was statistically significant linear correlation between i-PTH and AP. Other bone markers have no significant correlations with i-PTH. Our results demonstrated that there is significant bone loss in patients with CRF before the start of dialysis and also regional variations of BMDs in predialysis CRF patients. DXA is a useful method for evaluating regional and total BMDs and provides information about diverse regional skeletal changes. AP, i-PTH and U-DPD can predict BMD of predialysis CRF patients.

Alkaline Phosphatase↗

PubMed1996

Clinical features of ulcerative colitis in Korea.

OBJECTIVES: This study was conducted to investigate the clinical features of ulcerative colitis in Korea and to evaluate the clinical course after medical therapy. METHODS: Symptoms, signs and results of the treatment were retrospectively analyzed in 66 patients (male 32, female 34) diagnosed to have ulcerative colitis at the Asan Medical Center. RESULTS: The median age of the beginning of symptoms was 36 years (range, 14-72). Diarrhea and rectal bleeding were observed in 95.1 and 91.4%, respectively, at the time of diagnosis, while extra-colonic manifestations were observed in 24.1%. In 41 patients (62.1%), colitis developed in the rectum and sigmoid colon, while left colitis and extensive colitis developed in 11 (16.7%) and 14 patients (21.2%), respectively. The severity of disease was determined according to the clinical criteria, resulting in 22 (33.3%) mild, 21 (31.8%) moderate and 23 (34.8%) severe diseases. The seventy was also classified as 1, 2 and 3 by sigmoidocolonoscopic findings: 1;17 patients(25.8%), 2;27(40.9%) and 22(33.3%). Among 23 patients with severe disease, 5 patients (7.6%) received total colectomy due to toxic megacolon, intractability to medical therapy, ileocolic fistula and intestinal stenosis. The severity determined by colonoscopic findings was well correlated with that determined clinically and was closely related to the severity of symptoms, levels of albumin, hemoglobin and the count of leukocyte. The median duration of symptoms before treatment was 4 weeks (range, 11-300). All patients were treated with sulfasalazine and prednisolone. All patients with medical therapy, except 2 patients (96.7%), obtained clinical remission. The median days required for remission was 14 (range, 3-70). Relapse rates at 6 months, 1 year and 2 years after the initiation of treatment were 19.7, 34.1 and 49.3%, respectively. The median disease-free interval from the time of remission was 10 months (range, 2-60). After remission, the subsequent relapse rate increased in severe disease, while no difference was observed between the disease extents. CONCLUSIONS: The general characteristics of clinical manifestations and clinical course, after the medical treatment of ulcerative colitis in Korean patients, are not considerably different from those in Western countries.

Adolescent↗

PubMed1996