Biomedical subjects

Young Han Kim

Publications and source records attributed to Young Han Kim.

7 recordsLinked to original sources

PubMed2006

Neonatal outcome after preterm delivery in HELLP syndrome.

The present study compares neonatal outcome after preterm delivery of infants in pregnancies complicated by the HELLP syndrome or severe preeclampsia (PS). The maternal and neonatal charts of 71 out of a total of 409 pregnancies that were complicated by hypertensive disorders at Severance hospital between January 1995 and December 2004 were reviewed. Twenty-one pregnancies were complicated by HELLP syndrome and 50 pregnancies were complicated by PS. Fifty normotensive (NT) patients who delivered because of preterm labor comprised the control group. Results were analyzed by the chi-square test and ANOVA. Gestational age and maternal age at delivery were matched among the three groups. The neonatal outcomes of the HELLP syndrome group were compared with the PS and NT groups. There were significant differences between the HELLP syndrome group and the PS group in the incidence of intraventricular hemorrhage (IVH) (61.9% vs. 26%, p=0.006), sepsis (85.7% vs. 44%, p =0.003) and mechanical ventilation (MV) rate (81% vs. 54%, p=0.039). There were significant differences between the HELLP syndrome group and the NT group in the incidence of neonatal death (ND) (19.5% vs. 2.0%, p=0.034), respiratory distress syndrome (RDS) (38.1% vs. 8%, p=0.0045), IVH (61.9% vs. 4%, p < 0.0001), sepsis (85.7% vs. 14%, p < 0.0001), intensive care (IC) (85.7% vs. 24%, p < 0.0001) and MV rate (80.1% vs. 14%, p < 0.0001). There were also significant differences between the PS and NT groups in the incidence of ND (20% vs. 2%, p=0.0192), RDS (30% vs. 8%, p=0.0085), IVH (26% vs. 4%, p=0.0070), sepsis (44% vs. 14%, p=0.0015), IC (78% vs. 24%, p < 0.0001), MV rate (54% vs. 14%, p < 0.0001) and low 5-min APGAR score (50% vs. 16%, p=0.0005). This study shows increased morbidity in newborns of mothers complicated with HELLP syndrome and indicates that early, regular and high quality management of these patients is essential to improve both maternal and neonatal outcome.

Adult↗

PubMed2006

Clinical experiences of fetal ovarian cyst: diagnosis and consequence.

Ovarian cysts are the most frequent, prenatally diagnosed intra-abdominal cysts. Fetal ovarian cyst often presents complication such as torsion and seems to be an indication for surgical intervention. In this study, we reviewed pre- and post-natal medical records and ultrasonography of 17 fetuses that were diagnosed with ovarian cysts. In a total of 17 cases, postnatal surgery was performed in 7 infants. Of these cases, four cases of ovarian cyst torsion were confirmed. In the remaining 10 fetuses, one case regressed completely during pregnancy, and the other nine cases including two complex cysts resolve spontaneously after birth. Postnatal symptomatic cysts or cysts with a diameter greater than 5 cm that do not regress or enlarge should be treated, but uncomplicated asymptomatic cysts less than 5 cm in diameter should only be observed and reassessed by serial ultrasonography. If they regress spontaneously, no surgical intervention is necessary independent of their sonographic findings.

Female↗

PubMed2005

CLAGen: a tool for clustering and annotating gene sequences using a suffix tree algorithm.

Most multiple gene sequence alignment methods rely on conventions regarding the score of a multiple alignment in pairwise fashion. Therefore, as the number of sequences increases, the runtime of sequencing expands exponentially. In order to solve the problem, this paper presents a multiple sequence alignment method using a linear-time suffix tree algorithm to cluster similar sequences at one time without pairwise alignment. After searching for common subsequences, cross-matching common subsequences were generated, and sometimes inexact matching was found. So, a procedure aimed at masking the inexact cross-matching pairs was suggested here. In addition, BLAST was combined with a clustering tool in order to annotate the clusters generated by suffix tree clustering. The proposed method for clustering and annotating genes consists of the following steps: (1) construction of a suffix tree; (2) searching and overlapping common subsequences; (3) grouping subsequence pairs; (4) masking cross-matching pairs; (5) clustering gene sequences; (6) annotating gene clusters by the BLAST search. The performance of the proposed system, CLAGen, was successfully evaluated with 42 gene sequences in a TCA cycle (a citrate cycle) of bacteria. The system generated 11 clusters and found the longest subsequences of each cluster, which are biologically significant.

Algorithms↗

PubMed2005

Uterine artery Doppler velocimetry during mid-second trimester to predict complications of pregnancy based on unilateral or bilateral abnormalities.

We performed this study to evaluate uterine artery Doppler velocimetry (UADV) measurement of unilateral or bilateral abnormalities as a predictor of complications in pregnancy during the mid-second trimester (20-24 weeks). We enrolled 1,090 pregnant women who had undergone UADV twice: once between the 20th and 24th week (1st stage) and again between the 28th and 32nd week (2nd stage) of pregnancy, and then delivered at Yonsei Medical Center. UADV was performed bilaterally. Follow-up UADV was performed between the 28th and 32nd week, and the frequencies of pregnancy-induced hypertension (PIH), fetal growth restriction (FGR), and preterm delivery (before 34 weeks of gestation) were determined. Chi-squared and t-tests were used where appropriate, with p < .05 considered significant. According to the results of UADV performed between 20-24 weeks of gestation, 825 women (75.7%) were included in the normal group, 196 (18.0%) in the unilateral abnormality group, and 69 (6.3%) in the bilateral abnormality group. The incidences of FGR were 8.0%, 10.2%, and 26.1%, and the incidences of PIH were 0.1%, 3.6%, and 14.5%, respectively. The incidence of PIH was significantly lower in the normal group. The incidences of preterm delivery were 2.2%, 5.6%, and 8.7%, respectively. PIH developed in 46.7% of patients with bilateral abnormal findings in both the 1st and 2nd stage tests, and developed in none of the patients with normal findings in both tests. Abnormal results found by UADV performed between the 20-24th weeks of pregnancy, such as high S/D ratios regardless of placental location and the presence of an early diastolic notch, were associated with significant increases in the incidences of intrauterine growth restriction (IUGR) and PIH. This was true for both bilateral and unilateral abnormalities. Abnormal findings in bilateral UADV during the second trimester especially warrant close follow up for the detection of subsequent development of pregnancy complications.

Adult↗

PubMed2003

Early assessment of the therapeutic response to radio frequency ablation for hepatocellular carcinoma: utility of gray scale harmonic ultrasonography with a microbubble contrast agent.

OBJECTIVE: To evaluate the utility of gray scale harmonic ultrasonography with a microbubble contrast agent in the early assessment of the therapeutic response to radio frequency ablation for hepatocellular carcinoma. METHODS: Seventy-five patients with 81 nodular hepatocellular carcinomas (1.3-4.8 cm) treated with percutaneous radio frequency ablation were evaluated with contrast-enhanced gray scale harmonic ultrasonography after intravenous bolus injection of a galactose-based microbubble contrast agent. The vascularity within the ablation zones was evaluated with a continuous scan for 3 to 5 seconds between 15 and 30 seconds after initiation of contrast agent injection. To evaluate the perfusion of the ablation zones, intermittent stimulated acoustic emission imaging was performed with a rapid sweeping technique from the end of the continuous scan. All patients underwent follow-up 3-phase helical computed tomography at 1 month after radio frequency ablation and were followed for at least 1 year. The results of contrast-enhanced ultrasonography were compared with those of follow-up computed tomography in terms of the presence or absence of residual unablated tumors. RESULTS: In 10 (12%) of the 81 treated hepatocellular carcinomas, contrast-enhanced ultrasonography showed either nodular or crescentic enhancing foci at the margins of ablation zones, suggesting residual unablated tumors. Contrast-enhanced computed tomography obtained 1 month after radio frequency ablation confirmed the residual unablated tumors in the same 10 lesions. Diagnostic agreement between 1-month follow-up computed tomography and contrast-enhanced ultrasonography was achieved in all 81 cases (100%). CONCLUSIONS: Contrast-enhanced gray scale harmonic ultrasonography can be a reliable alternative to contrast-enhanced computed tomography in the early assessment of the therapeutic response to radio frequency ablation for hepatocellular carcinoma.

Adult↗

PubMed2002

Small pulmonary nodules on CT accompanying surgically resectable lung cancer: likelihood of malignancy.

SUMMARY: The aim of this study was to determine the likelihood of malignancy in small nodules in the nonprimary lobe in patients with resectable bronchogenic carcinoma. In 141 patients who underwent curative resection of bronchogenic carcinoma and had adequate follow-up CT examinations, the presence of small nodules in the nonprimary lobe preoperatively and change of preexisting nodules, if any, was assessed. The criteria used to determine benignity of a nodule was stability or decrease in size for 24 months on CT. Histopathology of the nodules was reviewed for an additional 10 patients who underwent surgical biopsy for an accompanying nodule before curative surgery. Sixty-two (44%) of 141 patients had a total of 138 small (< or = 10 mm) nodules in the nonprimary lobes (< 5 mm in 113, 5-10 mm in 25). Of these 138 nodules, 132 were benign with only six nodules malignant (with histopathologic confirmation for the enlarging nodules). The 132 benign nodules showed no change (n = 120), decrease in size (n = 11), or increase in size (n = 1) on follow-up studies, with the single enlarging nodule proved benign on biopsy. In 10 patients who had a preoperative biopsy of a single preexisting nodule in the nonprimary lobe (< 5 mm = 1; 5-10 mm = 5; > 10 mm = 4) two proved to be malignant (both > 10 mm) and eight were benign. Most small (< 10 mm) nodules associated with resectable bronchogenic carcinoma are benign, consistent with published results of other studies. However, a small number of nodules are malignant and CT does not reliably distinguish between benign and malignant nodules.

Adult↗

PubMedDate not supplied

Hepatocellular carcinoma treated with radio-frequency ablation: spectrum of imaging findings.

Contrast material-enhanced Doppler or gray-scale harmonic ultrasonography (US) may help determine the completeness or long-term therapeutic efficacy of radio-frequency (RF) ablation of hepatocellular carcinoma (HCC). Successfully treated HCC is devoid of vascularity at color or power Doppler US. When the tumor is not completely treated, residual viable tumor can be detected. These contrast-enhanced US techniques may also help identify residual tumor when performed during repeat RF ablation, when accurate localization of viable tumor is needed. To date, contrast-enhanced computed tomography (CT) has been the most widely used imaging modality in the evaluation of therapeutic response after RF ablation of HCC. At follow-up CT, successfully ablated lesions appear as low-attenuation areas with no foci of contrast enhancement either within or at the periphery of the treated lesion, whereas any foci of enhancement indicate residual or recurrent tumor. Reactive hyperemia in tissue surrounding the ablated lesion, iatrogenic arterioportal shunting, and small intralesional air pockets are frequently seen at immediate follow-up CT. Gadolinium-enhanced dynamic magnetic resonance imaging is also useful in assessing therapeutic response following RF ablation of HCC, particularly when CT findings are inconclusive. Familiarity with these imaging findings is helpful in this setting.

Adult↗