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B H Yoon

Publications and source records attributed to B H Yoon.

79 records · Page 5Linked to original sources
PubMed1983

Pulmonary scar carcinoma. A clinicopathologic analysis.

To delineate differences between scar and non-scar pulmonary carcinoma, the charts, autopsy protocols and chest roentgenograms of 80 male patients (autopsied) between 1975 and 1980, were reviewed. Nineteen patients (24%) had documented scar carcinomas. The comparison revealed scar carcinomas to possess certain distinctive features: A higher histologic distribution of adenocarcinoma (58% versus 15% in non-scars) and the frequent presentation (53%) with only nonpulmonary symptoms and signs related to metastasis. In scar carcinomas both bronchoscopy and sputum cytology were ineffective as initial diagnostic tools since chest findings were absent or minimal. Chest x-ray was negative in 9 of the 19 patients with scar cancer and remained negative until death in seven. In 10 of 19 instances, pulmonary scar carcinomas presented with only nonpulmonary symptoms and showed a tendency to metastasize while clinically undetectable. The differences noted between scar and non-scar carcinomas of the lung appear to depend on the peripheral location of these tumors and not on the adenocarcinoma histology.

Adenocarcinoma↗
PubMed1982

Aortic aneurysm producing back pain, bone destruction, and paraplegia.

Back pain and paraplegia are uncommon presenting symptoms/signs of aortic aneurysms. Extensive destructive changes were noted in the lower lumbar vertebrae in a 79-year-old man with an aneurysm that had eroded into the spine. The association of back pain with vertebral body erosion requires evaluation for vertebral or paravertebral abscess, neoplasia, and aortic aneurysm. Arteriography is usually required to demonstrate continuity with the vertebral body and to exclude the coincidental association of an aortic aneurysm with another pathology, i.e., neoplasm. Aggressive surgical treatment is recommended for any rapidly expanding aneurysm. The natural history of the untreated lesion is one of rapid demise.

Aged↗
PubMedDate not supplied

Matrix metalloproteinases-9 in preterm and term human parturition.

OBJECTIVE: Spontaneous rupture of the fetal membranes occurs after the commencement of labor in 90% of cases. Recent evidence indicates that the process of parturition requires not only an increase in myometrial contractility and cervical ripening, but also degradation of extracellular matrix in fetal membranes (i.e., leakage of fibronectin into cervico-vaginal secretions). This study was undertaken to determine if parturition is associated with in vivo evidence of increased bioavailability of matrix metalloproteinases-9 (MMP-9) and its inhibitor, tissue inhibitor of metalloproteinases-1(TIMP-1). METHODS: A cross-sectional study was conducted with women in the following categories: 1) midtrimester (n = 25); 2) preterm labor and intact membranes in the absence of intraamniotic infection (n = 78); 3) term not in labor (n = 25); and 4) term with intact membranes in labor (n = 25). MMP-9, and TIMP-1 were measured using sensitive and specific immunoassays. RESULTS: 1) Spontaneous labor at term was associated with a significant increase in MMP-9 but not in TIMP-1.2) Women with preterm labor who delivered prematurely had significantly higher concentrations of MMP-9 but not TIMP-1 in amniotic fluid than those with preterm labor who delivered at term. 3) The concentrations of TIMP-1 decreased with advancing gestational age. In contrast, MMP-9 concentrations did not change with advancing gestational age. CONCLUSIONS: Spontaneous human parturition is associated with specific changes in the enzymatic machinery responsible for extracellular matrix degradation.

Amniotic Fluid↗
PubMedDate not supplied

Amniotic fluid interleukin-6 determinations are of diagnostic and prognostic value in preterm labor.

PROBLEM: The purpose of this study was to determine if amniotic fluid concentrations of the interleukin-6 (IL-6) are of value in diagnosis of microbial invasion of the amniotic cavity and in the prediction of failure of tocolysis, preterm delivery and perinatal morbidity and mortality. METHOD: Amniotic fluid was obtained by transabdominal amniocentesis from 146 consecutive patients admitted with the diagnosis of preterm labor and intact membranes. Fluid was cultured for aerobic and anaerobic bacteria as well as for mycoplasmas. Amniotic fluid IL-6 levels were measured using a monoclonal antibody-based enzyme-linked immunosorbent assay with a sensitivity of 0.03 ng/ml. Logistic regression and Cox's proportional hazards model were used to examine the effect of several variables on dichotomous outcomes or interval to delivery. RESULTS: Patients with a positive amniotic fluid culture had a significantly higher amniotic fluid IL-6 concentrations than patients with a negative culture (median 91.2 ng/ml, range 0.9 to 437 ng/ml versus median 0.4 ng/ml, range < 0.3 to 195 ng/ml, respectively; P < .0001). An amniotic fluid IL-6 concentration of greater than or equal to 11.3 ng/ml had a sensitivity of 93.3% (14 of 15) and a specificity of 91.6% (120 of 131). All patients with an amniotic fluid IL-6 concentration above 11.3 ng/ml and a negative amniotic fluid culture (N = 11) delivered preterm and all placenta available for examination (N = 7) had histologic evidence of chorioamnionitis. Amniotic fluid concentrations of IL-6 were an independent predictor of preterm delivery, amniocentesis-to-delivery interval and neonatal morbidity and mortality. Moreover, IL-6 concentrations added significant information to the prediction of these outcomes to that provided only by clinical information such as cervical dilatation, gestational age at admission or at delivery. CONCLUSION: IL-6 is a sensitive and rapid test for the detection of microbial invasion of the amniotic cavity and for identifying women at risk for spontaneous preterm delivery and neonates at risk for morbidity and mortality.

Adult↗
PubMedDate not supplied

Treatment with the interleukin-I receptor antagonist and soluble tumor necrosis factor receptor Fc fusion protein does not prevent endotoxin-induced preterm parturition in mice.

OBJECTIVE: To determine whether the administration of anticytokine agents, the interleukin-1 receptor antagonist (IL-1ra) and a soluble tumor necrosis factor receptor Fc fusion protein (sTNFR-Fc), prevents endotoxin-induced preterm delivery in mice. METHODS: C3H/HeN pregnant mice at 15 days of gestation (70% gestation) were randomized to receive phosphate-buffered saline (PBS) or lipopolysaccharide (LPS) (50 micrograms/mouse) intraperitoneally (i.p.). Randomly selected PBS- or LPS-treated mice were additionally treated intravenously (i.v.), i.p., or subcutaneously (s.c.) every 3 hours with IL-1ra (1-50 mg) or every 12 hours with sTNFR-Fc (200-400 micrograms) beginning 1 hour before LPS injection. Animals were observed for vaginal bleeding and preterm delivery. RESULTS: Mice treated i.p. with 50 micrograms LPS (n = 13) had a shorter injection-to-delivery interval than mice treated similarly with PBS (n = 19) (median 13.5 hours, range 10-105 versus median 86.8 hours, range 53-120, respectively; P < .001). Saline-treated mice given 10 mg IL-1ra every 3 hours i.p. (n = 3) or 200 micrograms sTNFR-Fc every 12 hours i.v. (n = 4) had similar injection-to-delivery intervals as PBS-treated control mice (median 70 hours, range 70-76 versus median 58 hours, range 50-120, respectively). Similarly, LPS-treated mice given PBS every 3 hours (n = 20) had injection-to-delivery intervals comparable to LPS-treated mice (n = 13) (median 15.5 hours, range 9.8-92 versus median 13.5 hours, range 10-105, respectively). Lipopolysaccharide-treated mice given i.p. injections of 1 (n = 4), 10 (n = 31), or 50 (n = 15) mg of IL-1ra every 3 hours did not have longer injection-to-delivery intervals compared with LPS-treated mice (n = 13) (medians 11.6, 15, 14.5 and 13.5 hours; ranges 10.8-12, 8-95, 11-92, and 10-105, respectively). Lipopolysaccharide-treated mice given i.v. injections of 200 (n = 4) or 400 (n = 9) micrograms sTNFR-Fc every 12 hours did not have longer injection-to-delivery intervals compared with LPS-treated mice (n = 8) (medians 23.3, 22.5, and 21.9 hours; ranges 14.8-33, 15-95.5, and 15.5-44, respectively). The median injection-to-delivery interval of LPS-treated mice given both IL-1ra (10 mg) every 3 hours i.p. and sTNFR-Fc (200 micrograms) every 12 hours i.v. (n = 5) was not different from that of LPS-treated mice (median 26 hours, range 24.5-72 versus median 13.5 hours, range 10-105, respectively; P > .05). CONCLUSION: The anticytokine agents IL-1ra and sTNFR-Fc did not prevent preterm delivery or prolong pregnancy in endotoxin-induced preterm labor in mice.

Animals↗