Biomedical subjects

S Y Hong

Publications and source records attributed to S Y Hong.

At least 73 records · Page 4Linked to original sources

PubMed1995

Paraquat poisoning of the lung: thin-section CT findings.

PURPOSE: To describe thin-section computed tomographic (CT) findings in paraquat poisoning of the lung. MATERIALS AND METHODS: Thin-section CT scans of the lungs in 16 patients with paraquat poisoning were reviewed. The patients were nine male and seven female persons whose ages ranged from 16 to 74 years (mean, 29 years). Follow-up CT scans were available for seven patients. RESULTS: The most common pattern on initial scans was ground-glass attenuation, present alone or as part of a mixed pattern in 13 patients. It was bilateral and diffuse in distribution. Consolidation was present in six patients, irregular lines in three, and nodules in two patients. On follow-up scans, the ground-glass attenuation had changed to consolidation with bronchiectasis. Additional irregular lines and traction bronchiectasis also were observed. CONCLUSION: CT findings in paraquat poisoning of the lung begin with ground-glass attenuation, which leads to consolidation with bronchiectasis or irregular lines.

Adult↗

PubMed1995

Lipoprotein(a) levels and fibrinolytic activity in patients with nephrotic syndrome.

Recently there has been a renewed interest in the possibility that lipoprotein(a)--Lp(a)--may be important in the pathogenesis of thrombosis-related disease. In nephrotic syndrome, hyperlipidemia is a common finding, and thrombosis is a major complication. With this regard, if Lp(a) levels increase concomitantly with low-density lipoprotein and/or very-low-density lipoprotein levels in nephrotic syndrome, this may be considered a thrombogenic factor. To probe this possibility and to corroborate the relationship between Lp(a) and fibrinolytic profiles, we measured the Lp(a) levels in patients with nephrotic syndrome (n = 43), in patients with chronic glomerulonephritis with less proteinuria than in nephrotic syndrome (n = 28), and in healthy controls (n = 50) and observed the relation between Lp(a) levels and tissue-type plasminogen activator (t-PA) activity, euglobulin fibrinolytic activity, and t-PA antigen. The Lp(a) levels were significantly higher in the patients with nephrotic syndrome as compared with both patients with chronic glomerulonephritis and healthy controls (p < 0.001). There was a direct correlation with serum cholesterol level (r = 0.780; p = 0.0001), triglyceride level (r = 0.445; p = 0.0001), and urine protein level (r = 0.675; p = 0.0001) and a reverse correlation with serum albumin levels (r = 0.566; p = 0.0001). The Lp(a) levels showed a reverse correlation with t-pA activity (r = 0.627; p = 0.0001), total fibrinolytic activity in euglobulin fraction (r = 0.458; p = 0.0001), and t-PA activity divided by the t-PA antigen (r = 0.567; p = 0.0001), but no correlation with t-PA antigen.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1994

Plasma t-PA and PAI-1 antigen concentrations in non-insulin dependent diabetic patients: implication for diabetic retinopathy.

Parameters of fibrinolysis, including basal plasma tissue type plasminogen activator (t-PA) and plasminogen activator inhibitor type 1 (PAI-1) antigen levels were studied in 49 non-insulin dependent diabetic patients (23 men, 26 women: ages 51.3 +/- 14.9 years) and 16 age matched non-diabetic subjects (9 men, 7 women ages 49.8 +/- 12.2 years) as a control group. Compared to a control group, the diabetic patients had a significantly higher mean plasma t-PA antigen (4.94 +/- 2.68 vs 3.20 +/- 2.30 ng/ml) and PAI-1 antigen (34.86 +/- 16.71 vs. 17.60 +/- 15.36 ng/ml) levels (P < 0.05). Significant univariate correlations were observed between t-PA and body mass index (BMI) (P = 0.0009, r = 0.7217), and PAI-1 were positively correlated with BMI and FBS (fasting blood sugar) in the total diabetic patients (P = 0.0003, r = 0.7217; P = 0.0477, r = 0.2858, respectively). In diabetic patients with proliferative diabetic retinopathy, both PAI-1 and t-PA antigen levels were significantly lower than those of diabetic patients with negative or background retinopathy (P = < 0.05). There were no significant differences of the plasma t-PA and PAI-1 levels between diabetic patients with micro- and macroproteinuria. This study conducted on non-insulin dependent diabetic patients suggests that they have significantly higher t-PA and PAI-1 antigen levels than do control subjects, and these findings appear to correlate negatively with proliferative retinopathy observed among the patients studied.

Analysis of Variance↗

PubMed1994

Insulin levels and fibrinolytic activity in patients with end-stage renal disease.

Considering that PAI-1 is an important factor modulating the systemic fibrinolytic activity, the abnormal insulin metabolism frequently seen in end-stage renal disease (ESRD) may cause decreased fibrinolytic activity in concert with PAI-1. To study this possibility, we measured insulin levels and compared it with the fibrinolytic profiles in ESRD patients. Fasting blood sugar, insulin, and C peptide levels were higher in ESRD patients than in the control group. In the ESRD patients, the insulin levels showed a positive correlation with C peptide (r = 0.612, p = 0.0001), fasting blood sugar (r = 0.334, p = 0.044), and PAI-1 antigen (r = 0.474, p = 0.0001) and a reverse correlation with euglobulin fibrinolytic activity (r = 0.5, p = 0.005), but no correlation with t-PA antigen. The euglobulin fibrinolytic activity showed a reverse correlation with PAI-1 antigen (r = 0.289, p = 0.0144), but no correlation with t-PA antigen. Our results suggest that abnormal insulin metabolism and/or insulin resistance, which occur frequently in ESRD, may play an important role in the decrease in systemic fibrinolytic activity by the regulation of the PAI-1 concentration.

Blood Glucose↗

PubMed1994

[Pathological study on placenta from pregnancies with systemic lupus erythematosus].

Pathological study on the placenta of 18 cases of pregnancy complicated with systemic lupus erythematosus (SLE) and 23 cases of normal pregnancy was done. The average weight and placenta-villi area ratio of the placenta from pregnancy with SLE were significantly lower than those of the normal (P < 0.05). Scanning under electron microscope showed the placental villi of the SLE group slender and branching little, with their ends bean-sprout looking and the surface covered with pin-point holes, even slitted masses. Immunohistologic examination indicated deposition of IgG, IgA, IgM, C3 on the villi capillary wall surface, which suggested damage of the placental function of the SLE gravidae by the immunologic compounds.

Adult↗

PubMed1994

Increasing prevalence of antimicrobial resistance among organisms isolated from blood culture in a Singapore hospital.

The blood culture isolates obtained over the period 1985-1990 in a general teaching hospital were reviewed to determine trends in the prevalence of resistance to antimicrobial drugs. The percentages of Staphylococcus aureus isolates resistant to methicillin increased each year. Resistance among coagulase negative staphylococci also increased in prevalence: by 1990 approximately 50% of such isolates were resistant to methicillin, erythromycin, co-trimoxazole and gentamicin, 24% were resistant to clindamycin, 20% to fucidic acid but only 0.5% to vancomycin. Isolates of Enterobacteriaceae, excluding community-acquired salmonellae, showed increasing prevalence of resistance to beta-lactams, as did Acinetobacter spp isolates to gentamicin, co-trimoxazole and ceftriaxone. The isolates of Pseudomonas aeruginosa were exceptional, having no evident increase in the prevalence of resistance during the period. The rapid increases observed in relation to the other pathogens indicate the need for an antibiotic policy based on continuous surveillance of susceptibility patterns in the hospital.

Anti-Bacterial Agents↗

PubMed1994

[Correlation between outcome of pregnancy and condition of disease at conception in systemic lupus erythematosus women].

Thirty four pregnant patients with systemic lupus erythematosus (SLE) were divided into 3 groups: (1) primigravida, (2) previous history of spontaneous abortion, and (3) previous history of induced abortion. Outcomes of these pregnancies showed that the average birth weight in primigravida group was significantly higher than that in the other 2 groups (P < 0.05). Grouping by clinical status of SLE at conception, there were 4 kinds of situation: (1) remission, (2) controlled, (3) active, and (4) first onset. Patients with SLE of active stage had the lowest birth weight and gestational age babies (P < 0.05). The best time for conception in SLE women was at the time of remission or controlled stage, i.e. patients treated with prednisone in a dose of 5-15 mg/day for more than 6 months or without any medication for at least 1 year.

Adult↗

PubMed1993

Fibrinolytic activity in end-stage renal disease.

Recently, we described that in the physiologic state, urokinase concentration is higher in the renal vein than in the renal artery which suggests that the kidney is the essential organ providing urokinase to the systemic circulation. In end-stage renal disease (ESRD) patients, urokinase provided by the kidney may be decreased, and this might be the cause of decreased systemic fibrinolytic activity seen in ESRD. To study this possibility, we measured fibrinolytic profiles including urokinase, tissue plasminogen activator (t-PA) and fibrinolytic activity in the euglobulin fraction of ESRD patients and compared the results with those of two control groups consisting of renal transplantation patients and age- and sex-matched healthy controls. The euglobulin fibrinolytic activity was 92.2 +/- 14.8 BAU in the ESRD group, 108.7 +/- 13.5 BAU in the kidney transplantation (KT) group and 101.5 +/- 8.0 BAU in the healthy control group. Although it was lower in the ESRD than in the KT (p < 0.005) and the healthy control group (p < 0.005), there was no difference between the KT and the healthy control group. t-PA antigen was 1.2 +/- 1.3 ng/ml in the ESRD group, 3.5 +/- 1.7 ng/ml in the KT group and 3.1 +/- 2.1 ng/ml in the healthy control group. It was lower in the ESRD compared to the KT (p < 0.001) and the healthy control group (p < 0.001) but there was no difference between the KT and the healthy control group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1992

Urokinase concentration in the renal artery and vein.

To compare the fibrinolytic activity between the renal artery and vein and the systemic circulation, we measured tissue-type plasminogen activator (t-PA), urokinase and total fibrinolytic activity in the blood samples from both the left and right renal artery and vein and the anterior cubital vein of 7 kidney donors. Englobulin fibrinolytic activity was significantly higher in the renal vein [106.6 +/- 5.6 blood activator units (BAU)] than in the renal artery (90.6 +/- 4.1 BAU; p less than 0.001) and cubital vein (94.3 +/- 6.3 BAU, p less than 0.005), but there was no difference between renal artery and cubital vein. t-PA Ag was 2.9 +/- 1.1 ng/ml in the renal vein, 2.6 +/- 1.0 ng/ml in the renal artery and 2.6 +/- 1.1 ng/ml in the cubital vein. There was no difference between renal artery, renal vein and cubital vein. Urokinase was significantly higher in the renal vein (3.3 +/- 0.4 ng/ml) than in the renal artery (2.4 +/- 0.4 ng/ml; p less than 0.001) and cubital vein (2.6 +/- 0.4; p less than 0.005), but there was no difference between the renal artery and cubital vein. In all cases, there was no difference in the fibrin(ogen) degradation product concentration between the renal artery and vein and the cubital vein. These findings suggest that the kidney may be an essential organ for providing urokinase to the systemic circulation.

Feedback↗

PubMed1992

Effect of periodic transfusion on erythropoietin concentration in end stage renal disease.

BACKGROUND: It has been reported that a feedback circuit exists between erythropoietin (EPO) concentration and the degree of anemia even in end stage renal disease (ESRD), and growing experience with subcutaneous EPO administration confirms that only slight increases in EPO levels are required to correct renal anemia. Keeping in mind these findings, if a small portion of reserved EPO production could be reactivated in ESRD, it might be biologically significant and vice-versa. From this viewpoint, it is conceivable that periodic long term transfusion might suppress EPO production in ESRD. METHODS: In order to see whether periodic transfusion influences the EPO concentration in ESRD, a cross-sectional retrospective study was undertaken by reviewing medical records of 28 non-transfusion patients and 22 transfusion patients with ESRD undergoing hemodialysis. RESULTS: The EPO concentration of the ESRD group (29.1 +/- 8.0 mU/ml) but only about one twentieth of the control group (578.8 +/- 69.1 mU/ml). In ESRD group, It was 27.9 +/- 8.0 mU/ml in transfusion group and 30.6 +/- 7.9 mU/ml in non-transfusion group. EPO concentration at varying hematocrit (Hct) levels did not differ between the non-transfusion group and transfusion group. There was an inverse relationship seen in the non-transfusion group (p < 0.05) but no relationship was seen between the EPO concentrations and varying Hct levels in the transfusion group. The EPO concentration at equal levels of Hct did not differ between the non-transfusion group and transfusion group. The relationship between EPO concentration and the changes in Hct during the observation period did not differ between the non-transfusion group and transfusion group. Both the total amount of transfusion and the frequency of transfusions did not influence EPO concentration. CONCLUSION: periodic long term transfusion does not seem to decrease the sensitivity of the EPO producing cell to the degree of anemia in ESRD.

Adult↗

PubMed1992

The effect of dilution, pH and ionic strength of plasma on t-PA precipitation in euglobulin fraction.

In order to evaluate the influence of dilution, pH and ionic strength on the precipitation of t-PA and PAI-1 during euglobulin precipitation, we measured t-PA Ag, PAI-1 Ag and fibrinolytic activity in the euglobulin fraction made of pooled plasma from liver cirrhosis patients, under various conditions by changing pH, ionic strength and degree of dilution. The precipitation of t-PA Ag in the euglobulin fraction was enhanced by decreasing the ionic strength and greatest at pH 6.0. The fibrinolytic activity in the euglobulin fraction showed consistent changes with t-PA Ag under varying pH and ionic strength. The precipitation of t-PA Ag was not influenced by the dilution factor but the larger the dilution factor, the greater the PAI-1 and the smaller the fibrinolytic activity in the euglobulin fraction. PAI Ag in euglobulin fraction showed consistent changes with t-PA Ag in the euglobulin fraction regardless of the changes in ionic strength and pH. The amount of precipitation of t-PA and PAI-1 was increased by the presence of dextran sulfate, under varying pH, ionic strength and dilution conditions. Our results show that the currently used conditions for standard euglobulin precipitation are the most favorable for t-PA precipitation into the euglobulin fraction. The fibrinolytic activity exerted in the euglobulin fraction seems to depend on the amount of t-PA-PAI-1 complex rather than minimized protease inhibitor in the euglobulin fraction.

Fibrinolysis↗

PubMed1992

Plasma t-PA and PAl-1 antigen concentrations in non-insulin dependent diabetic patients: effects of treatment modality on fibrinolysis.

Basal plasma tissue type plasminogen activator (t-PA) and plasminogen activator inhibitor type 1 (PAl-1) antigen levels were studied in 49 non-insulin dependent diabetic patients (23 men, 26 women: ages 51.3 +/- 14.9 years) and 16 age matched non-diabetic subjects (9 men, 7 women: ages 49.8 +/- 12.2 years) as a control group. Compared to a control group, the diabetic patients had a significantly higher mean t-PA antigen (5.15 +/- 3.02 vs 3.20 +/- 2.30 ng/ml) and PAl-1 antigen (35.89 +/- 18.59 vs 17.60 +/- 15.36 ng/ml) levels (p < 0.05). Plasma t-PA antigen level was not influenced by each treatment modality. There was a significant decrease of plasma PAl-1 antigen level after Metformin administration compared to that of before Metformin administration (39.74 +/- 19.39 vs 25.14 +/- 16.18 ng/ml) (p < 0.05), and the insulin-treated group showed a tendency for a decrease of plasma PAl-1 antigen levels after insulin administration but this did not reach statistical significance (29.93 +/- 15.37 vs 17.32 +/- 10.60 ng/ml). Sulfonylurea did not change both plasma t-PA and PAl-1 antigen levels. In conclusion, diabetic patients have high t-PA and PAl-1 antigen levels. Biguanide reduced plasma PAl-1 antigen levels, which might play some helpful role in the improvement of chronic complications in NIDDM.

Antigens↗

PubMed1991

Euglobulin fibrinolytic activity in NIDDM patients.

The euglobulin fibrinolytic activity was measured in 56 non-insulin-dependent diabetics and 118 age-matched healthy controls before and after venous occlusion for 5 min at 100 mmHg of the left antecubital vein. In the basal state, fibrinolytic activity was impaired in diabetics compared with controls (93.1 +/- 6.7 vs 101.6 +/- 0.9 BAU) (P less than 0.05) and plasma fibrinogen level was increased but this did not reach statistical significance (467.3 +/- 264.1 vs 359.2 +/- 200.2 mg/dl). In diabetics, stimulated fibrinolysis following venous occlusion was depressed compared with controls (110.6 +/- 3.9 vs 121.6 +/- 1.9 BAU) (P less than 0.05). No relation of fibrinolytic activity to age, duration of diabetes, obesity, serum triglyceride, HbA1c, or 24 h proteinuria was demonstrated. In the diabetic retinopathy group, the fibrinolytic activity was lower than in the non-retinopathy group. Diabetics with long-standing diabetes (10 years or more) who remained free from retinopathy had significantly increased fibrinolytic activity than the diabetics with short-standing diabetes (less than 10 years) who have developed retinopathy (P less than 0.05). These findings imply a poor fibrinolytic activity, not in all diabetics, but only in those with retinopathy, and this may play a role in the development of diabetic retinopathy.

Age Factors↗

PubMed1991

Immunoregulatory effects of phospholipase A2 (PLA2) on the proliferation of human lymphocytes.

Extracellular phospholipase A2 (PLA2) is a proinflammatory enzyme found especially in the inflammatory exudate to modulate blood flow to areas of antigen stimulation. In this study we found that PLA2 exerted a biphasic effect on the proliferation of phytohemagglutinin (PHA)-stimulated human mononuclear cells (PHA MNC). At low concentrations range from 0.001 to 1 U/ml, PLA2 enhanced the proliferation of PHA MNC (maximal increase was 37.0 +/- 5.67%). Conversely, at concentrations over 10 U/ml, PLA2 markedly suppressed the PHA-induced MNC proliferation (maximal decrease was 88.86 +/- 2.89%). PLA2 was non-toxic to lymphocytes after three days culture, unless the concentration was higher than 100 U/ml. The membrane polarization of PHA-stimulated lymphocytes was also increased by PLA2 at a low concentration. In addition, PLA2 displayed a similar effect on the proliferation of streptokinase-streptodornase (SK/SD) or allogeneic cell stimulated lymphocytes. The change of lymphocyte proliferation by PLA2, was parallel to the change of percentage of helper T cells. Furthermore--a CD4-rich population was proved more susceptible to PLA2 effect than a CD8-rich population. Para-bromophenacyl bromide (pBPB), an irreversible inhibitor of PLA2, abrogated the biphasic effect of PLA2 on PHA MNC proliferation. These results suggest that PLA2 plays a regulatory role on immune reactions by modulating the percentage of helper T cells.

Deoxyribonucleases↗

PubMed1991

Circulating HBsAg/IgG complexes in idiopathic chronic glomerulonephritis.

We measured HBsAg/IgG complexes (CX) quantitatively by ELISA from HBsAg positive serum of 35 liver disease patients, 15 patients with glomerular diseases (8 membranous glomerulonephritis (MGN) 7 membranoproliferative glomerulonephritis (MPGN), and 50 healthy carriers of HBsAg. HbsAg/IgG CX was detected in 26 out of 35 liver disease patients (74.3%), 5 out of 50 healthy carriers (10%), and one of both 8 MGN patients (12.5%) and 7 MPGN patients (14.3%). HBsAg/IgG CX was big in size and wide spread in the liver disease groups but negligible in the healthy carrier group (41 +/- 2.6 ng/ml, n = 5) and MGN (50 ng/ml, n = 1) and MPGN (42 ng/ml, n = 1) group. In the liver disease group, no one suffered from glomerulopathy even with a wide spectrum of HBsAg/IgG CX. These results suggest that HBsAg/IgG CX in plasma is non causative of MGN and MPGN.

Adult↗

PubMed1991

The urine urokinase concentration in end stage renal disease with acquired renal cyst.

To see whether there was any difference in the urine urokinase concentration between acquired cystic kidney disease (ACKD) group and control (non cyst) group in end stage renal disease patients (ESRD), we evaluated fifty ESRD patients who had been maintained on chronic hemodialysis for various period. The urine urokinase concentration was higher in the ACKD group (17.5 +/- 14.7 unit/ml, range 13.5-47.0 unit/ml, n = 9) than the control group (4.1 +/- 3.4 unit/ml, range 0.5-12.0 unit/ml, n = 36) (p less than 0.001), and polycyst group (2.6 +/- 1.8 unit/ml, range 1.0-5.1 unit/ml, n = 5) (p less than 0.01). But there was no difference between the control group and polycyst group. In the control group and the ACKD group, there was a direct relation between the dialysis duration and the urokinase concentration and the longer the dialysis duration, the higher the urine urokinase concentration (r squared = 0.424, p = 0.0001). The hemodialysis duration was longer in the ACKD group (42 +/- 17.0 months) than the control group (20.0 +/- 12.5 months) (p less than 0.005). These findings suggest that urokinase may be responsible for cystogenic degeneration in ESRD.

Adult↗

PubMed1991

[Clinical effects and immune regulation of musk-moxa-string therapy in 39 patients with scrofula].

Immunological function and lymphocytic subsets of peripheral blood mononuclear cell (PBWC) from 39 patients with scrofula were investigated before and after treatment with musk-moxa-string therapy. The results showed that the percentage of CD3+, CD4+ cells and the ratio of CD4+/CD8+ cells were markedly decreased in the patients than normal control (P less than 0.001). On the contrary, the numbers of B lymphocytes and DR+ cells were increased. But the response of PBWC to phytohemagglutin in (PHA) stimulation markedly decreased in the patients than the normal control. After treatment with musk-moxa-string therapy, the percentage of CD3+, CD4+ cells and the ratio of CD4/CD8 were increased (P less than 0.001) and blastogenic response to mitogen stimulation with PHA recovered to normal. Meanwhile, the symptoms was improved and swell lymph node disappeared or was reduced markedly in size and the ulcer was healed completely. These findings suggest that the effect of musk-moxa-string therapy is caused by the enhancement of immunological capacity of the patients.

Adolescent↗

PubMed1991

Effect of 1,25-dihydroxyvitamin D3 on mesangial cell proliferation.

We have studied the effect of 1,25-dihydroxyvitamin D3 (1,25, (OH)2D3) on mesangial cell growth. Previous studies have shown that the monocyte-macrophage is the principal effector cell in immune-mediated nephritis; this cell infiltrates the glomerular mesangium, and its products may have important effects on the physiology of the mesangial cell. One of the substances produced by the activated macrophage is 1,25,(OH)2D3. We have investigated the effect of 1,25,(OH)2D3 on mesangial cell growth and found that this vitamin D metabolite suppresses the proliferation of mouse mesangial cells as assessed by mesangial cell tritiated thymidine uptake and by cell counts; this substance also antagonizes the mitogenic effect of epidermal growth factor on mesangial cell growth. By comparison, the vitamin D metabolite 25 hydroxyvitamin D3 has no significant suppressive effect on the proliferation of mesangial cells. It has also been possible to demonstrate that 1,25,(OH)2D3 could suppress the growth of mesangial cells that had been committed to proliferate by the prior addition of epidermal growth factor. The results of these studies are relevant to our understanding of the pathogenesis of the cellular abnormalities that occur in immune-mediated nephritis, and especially in subjects who have concurrent hypertension, because a segment of subjects with hypertension have demonstrable abnormalities in the levels of circulating 1,25,(OH)2D3.

Animals↗