Biomedical subjects

J Y Han

Publications and source records attributed to J Y Han.

At least 37 records · Page 2Linked to original sources

PubMed2001

Detection of fetal erythroid cells from maternal blood using fluorescence in situ hybridization and liquid culture.

Fetal nucleated erythrocytes circulating in maternal blood are a potential source of fetal DNA for noninvasive prenatal genetic diagnosis. However, the estimated ratio of fetal to maternal cells is extremely small. In order to enrich these cells, we performed direct culture using a two-phase liquid system. Mononuclear cells were obtained from maternal blood samples at 8-10(+3) weeks of gestation and cultured in the first phase. After 4-5 days, the nonadherent cells were harvested and recultured with erythropoietin in the second phase for another 3-5 days. We examined cellular morphology, and counted the number of benzidine- positive cells and the percentage of glycophorin A/CD71 positive erythroid cells. We also did Kleihauer-Betke stain for Hb F, polymerase chain reaction (PCR) for SRY/DYZ1, chromosome analysis, and fluorescence in situ hybridization (FISH). The number of total erythroid cells reached about 0.1 x 10(6)-1.0 x 10(6)/mL with a purity of 84.0-97.3%. Hb F stain showed total erythroid cells of approximately 0.4 x 10(4)-9.8 x 10(4)/mL. Male DNA was detected in one case by PCR. In this case, the XY karyotype was confirmed by FISH and amniocentesis. This approach provides enriched source of fetal cells for further prenatal genetic analysis without complicated separation or sorting procedures.

Cell Culture Techniques↗

PubMed2001

Frequencies of fetal chromosomal abnormalities at prenatal diagnosis: 10 years experiences in a single institution.

We present frequencies of fetal chromosomal abnormalities in 4,907 prenatal cytogenetic examinations at Samsung Cheil Hospital from 1988 to 1997 for 10 yr duration. Prenatal karyotypes were undertaken in 3,913 amniotic fluid samples, 800 chorionic villi samples, and 194 percutaneous umbilical blood samples. The frequency of fetal abnormal karyotypes was 3.1% (150 cases). Numerical chromosome abnormalities were 87 cases (1.8%) and structural aberrations of chromosomes were 63 cases (1.3%). In the numerical chromosomal abnormalities, the frequency of trisomy 21 was by far the highest (36 cases), followed by trisomy 18 in 22 cases and sex chromosome aneuploidies in 19 cases. In the structural chromosomal aberrations, 5 cases had the inversions in chromosome 2, 7, 17, and Y. Chromosomal deletions in 6 cases and additions in 4 cases were analysed. Of the remaining 47 translocation in abnormal fetuses, reciprocal translocation was in 26 cases and Robertsonian translocation in 21 cases. Among them, 41 cases were balanced translocation and 6 were unbalanced. Thirty five cases of translocation were inherited from one of the parents. Four had de novo chromosome rearrangements, and 8 cases were unknown.

Chromosome Aberrations↗

PubMed2001

The relationship of histologic activity to serum ALT, HCV genotype and HCV RNA titers in chronic hepatitis C.

It is unclear whether serum ALT levels or virological characteristics of hepatitis C virus(HCV) including HCV genotypes and HCV RNA titers, can reflect the degree of histological injury in chronic hepatitis C. The aim of this study was to investigate the relationships between the levels of histological damage and serum ALT levels, HCV genotypes or circulating HCV RNA titers in chronic hepatitis C. A total of 56 patients underwent liver biopsy and the histological activity index (HAI) was evaluated by Knodell's scoring system. HCV genotype by RT-nested PCR and HCV RNA quantitation by competitive RT-PCR were performed. Thirty-four patients were infected with HCV genotype 1b, 20 patients with genotype 2a, and 2 patients with undetermined type. Serum ALT levels were not positively correlated with total HAI score or HCV RNA titers, but showed a linear correlation with scores of piecemeal necrosis (r=0.32, p<0.05) and portal inflammation (r=0.27, p<0.05). HCV genotype had no significant correlation with RNA titers, HAI score or with serum ALT levels. Also, no statistical relationship was seen between HCV RNA titer and HAI score. These results suggest that liver histology is essential to evaluate the severity of chronic hepatitis C precisely.

Adolescent↗

PubMed2001

A case of hemorrhagic gallbladder paraganglioma causing acute cholecystitis.

Gallbladder paraganglioma is a very rare tumor and so far only a few cases have been reported. Most of these were asymptomatic and were found incidentally during operation. Recently, we experienced a gallbladder paraganglioma that gave rise to hemorrhage, which in turn caused acute cholecystitis. Our case involved a 45 year-old female patient complaining of an intermittent right upper abdominal pain. After a preoperative evaluation, cholecystectomy and lymphadenectomy were performed under the impression of gallbladder cancer with acute cholecystitis. Postoperative pathologic examination revealed a hemorrhagic gallbladder paraganglioma accompanied by acute cholecystitis. Immunohistochemical staining of the chief cells for neuron specific enolase, chromogranin and synaptophysin were positive. Sustentacular cells also stained positively for S100 protein.

Acute Disease↗

PubMed2001

Fatal pulmonary-renal syndrome manifested with immune complex crescentic glomerulonephritis in a patient with MPO-ANCA seropositivity.

Recent reports have indicated that a significant number of immune complex glomerulonephritis (GN) cases are associated with antineutrophilic cytoplasmic antibody (ANCA). However, most of the reported cases were associated with underlying primary glomerular diseases. When primary glomerular diseases were not found, immune deposits tended to be non-specific and the level of ANCA is usually borderline. We report here upon a case of life-threatening pulmonary-renal syndrome manifested simultaneously with immune complex GN and myeloperoxidase (MPO)-ANCA seropositivity. A 29- year-old man was admitted with pulmonary hemorrhage and rapidly progressing renal dysfunction. On admission, ANCA revealed perinuclear staining with a titer of 1:160. The MPO-ANCA level was 59 IU by ELISA. Other serologic markers including ANA, anti-DS-DNA and anti-GBM Ab were negative. Renal biopsy showed cellular crescents in eight of 18 glomeruli. Immunofluorescence staining showed strong granular deposits of C3, C1q, IgG and IgM in the capillary loop and the mesangium. Electron microscopy showed multifocal electron dense deposits scattered in the mesangium, paramesangium, and the subendothelial and subepithelial areas. The patient initially responded to steroid and cyclophosphamide. MPO-ANCA decreased to less than 10 IU. Twenty three days after hospital discharge, the patient was re-admitted urgently with fever, generalized papulonodular skin lesions, and a recurrence of massive pulmonary hemorrhage and renal dysfunction. He died from uncontrolled pulmonary hemorrhage and respiratory insufficiency. P-ANCA titer and MPO-ANCA level at the second admission were 1:320 and 82 U/ml respectively. Interestingly, relapse was shown to be triggered by varicella zoster infection.

Adult↗

PubMed2001

Enrichment and detection of fetal erythroid cells from maternal peripheral blood using liquid culture.

Isolating fetal cells from maternal blood for prenatal genetic analysis is the least invasive method currently being investigated. In order to enrich these fetal erythroid cells we employed a two-phase liquid culture system that supports the growth and differentiation of erythroid progenitor cells. Mononuclear cells were separated from ten maternal blood samples at 8-14(+3) weeks of gestation and cultured in the first phase. After 4-5 days, the non-adherent cells were harvested and recultured with erythropoietin for another 3-4 days. The mean number of total erythroid cells reached approximately 0.77x10(6)/ml with an average purity of 90.5%. Hb F stain disclosed fetal erythroid cells averaging approximately 5.7%, therefore the mean number of fetal erythroid cells isolated was 0.49x10(5)/ml. Female karyotypes were only observed while counting 5-66 metaphases. However, male DNA (SRY or DYZ1) was detected by PCR in 7/10 cases; in four of these cases and in one SRY-negative pregnancy the 46,XY karyotype was found by amniocentesis performed during the second trimester. This liquid culture system provided an enriched source of fetal cells without the need for more complicated separation or sorting procedures.

Blood Cells↗

PubMed2001

Involvement of p38 kinase in hydroxyurea-induced differentiation of K562 cells.

Hydroxyurea is a differentiation-inducing agent of human erythroleukemia K562 cells. However, the cellular mechanisms by which hydroxyurea exerts its effects on tumor cells, leading to the inhibition of cell growth and the induction of differentiation markers, are largely unknown. This study examined the role of different mitogen-activated protein kinase signal transduction pathways in hydroxyurea-induced erythroid differentiation of K562 cells. Using a panel of anti-extracellular signal-related kinase (ERK), c-Jun NH2-terminal kinase (JNK), and p38 phosphospecific antibodies, we demonstrated that phosphorylation of ERK and JNK is decreased after the treatment of cells with hydroxyurea, whereas phosphorylation of p38 is increased. Moreover, inhibition of ERK activity by PD98059 induced erythroid differentiation, and it acted synergistically with hydroxyurea on hemoglobin synthesis, whereas inhibition of p38 activity by SB203580 inhibited induction of hemoglobin production by hydroxyurea. These findings suggest that the activation of p38 kinase may play important roles in the signal transduction mechanisms of hydroxyurea leading to erythroid differentiation.

Cell Differentiation↗

PubMed2000

A DNA vaccine encoding a conserved Eimeria protein induces protective immunity against live Eimeria acervulina challenge.

Coccidiosis is caused by several distinct intestinal protozoa of Eimeria sp., and is responsible for intestinal lesions and severe body weight loss in chickens. To develop a DNA vaccination strategy for coccidiosis, an expression vector pMP13 encoding a conserved antigen of Eimeria was constructed by subcloning 3-1E cDNA into pBK-CMV and used to elicit protective immunity against E. acervulina. One-day-old chickens were immunized intramuscularly (IM) or subcutaneously (SC) with various doses of pMP13 expression vector ranging from 5 to 100 ug two weeks apart and were challenged with 5x10(3) E. acervulina. Chickens immunized with 5, 10, 50 or 100 ug of pMP13 plasmid, but not control plasmid, pBK-CMV, showed significantly reduced oocysts following challenge infection with E. acervulina. Two injections were in general more effective than one injection with higher dose of DNA eliciting better protection. At 10 days post challenge infection, maximum levels of circulating antibodies were detected regardless of the routes of injection, although IM injection provided higher levels of serum antibodies compared to SC injection. Serum antibody levels demonstrated a dose-dependent response showing higher antibody production at higher DNA dose. DNA immunization with pMP13 also induced significant changes in T-cell subpopulations in the spleen and duodenum intraepithelial lymphocytes. At 4 days post DNA immunization, pMP13-immunized chickens showed lower CD8, and higher CD4(+) and gammadelta T(+) cells in the duodenum compared to the pBK-CMV-immunized chickens. Following challenge infection with E. acervulina, pMP13-immunized chickens showed lower CD8(+) and alphabeta T(+) cells, and higher CD4(+) cells than pBK-CMV-immunized chickens in the duodenum. These findings demonstrate that DNA immunization with pMP13 induce local and systemic host immune responses against Eimeria.

Animals↗

PubMed2000

Detection of cryptic Y chromosome mosaicism by coamplification PCR with archived cytogenetic slides of suspected Turner syndrome.

Turner syndrome is one of the most common cytogenetic abnormalities. It is known that the Y chromosome or Y derived material is present in 6-9% of TS patient and it may develop a high risk of gonadoblastoma in 15-25%. So it is crucial to carry out cyto genetic analysis and Y-specific probe studies for all persons with gonadal dysgenesis to rule out mosaicism with Y-bearing cell line; eg 45,X/46,XY. In this study, 26 archival slides previously analyzed cytogenetically as 45,X, 45,X/46,X,i(X), 45,X/46,X,r(X), and 45,X/46,XX were examined. Coamplification PCR, having the advantage of providing rapid result and confirming PCR failure, was performed with the slide samples in the regions of dystrophin gene in Xp21and DYZ3 in the Y centromeric region. All of archived slides were positive for X-specific gene and one slide of 45,X was found to have the cryptic Y chromosome material. Our result suggests that the archived cytogenetic slides could be applied for the detection of Y chromosome rapidly and efficiently in TS patients.

Biopsy↗

PubMed2000

Derivation and characterization of pluripotent embryonic germ cells in chicken.

Embryonic germ (EG) cell lines established from primordial germ cells (PGCs) are undifferentiated and pluripotent stem cells. To date, EG cells with proven germ-line transmission have been completely established only in the mouse with embryonic stem (ES) cells. We isolated PGCs from 5.5-day-old (stage 28) chicken embryonic gonads and established a putative chicken EG cell line with EG culture medium supplemented with stem cell factor (SCF), leukemia inhibitory factor (LIF), basic fibroblast growth factor (bFGF), interleukin-11 (IL-11), and insulin-like growth factor-I (IGF-I). These cells grew continuously for ten passages (4 months) on a feeder layer of mitotically active chicken embryonic fibroblasts. After several passages, these cells were characterized by screening with the periodic acid-Schiff reaction, anti-SSEA-1 antibody, and a proliferation assay. The chicken EG cells maintained characteristics of gonadal PGCs and undifferentiated stem cells. When cultured in suspension, the chicken EG cells successfully formed an embryoid body and differentiated into a variety of cell types. The chicken EG cells were injected into stage X blastodermal layer and produced chimeric chickens with various differentiated tissues derived from the EG cells. Chicken EG cells will be useful for the production of transgenic chickens and for studies of germ cell differentiation and genomic imprinting.

Alkaline Phosphatase↗

PubMed2000

Myositis ossificans of the chest wall simulating malignant neoplasm.

Myositis ossificans originating from the chest wall is extremely rare. We report a case of myositis ossificans occurring in a young woman with progressive painful swelling in the chest wall. Preoperative examination suggested a malignant neoplasm originating from soft tissue. Although rare, myositis ossificans is one of the potential causes of painful swelling in the chest wall, and can be mistaken for a malignant neoplasm.

Adolescent↗

PubMed2000

Overexpression of c-H-ras p21 is correlated with vascular endothelial growth factor expression and neovascularization in advanced gastric carcinoma.

BACKGROUND AND AIMS: ras Gene and its product (p21) have been reported to be associated with vascular endothelial growth factor (VEGF), which is one of the most important angiogenic factors, and tumor-associated angiogenesis. We tried to evaluate the correlation between the expression of c-H-ras gene product p21 and angiogenesis in advanced gastric carcinoma. METHODS: Immunohistochemical expression of c-H-ras p21 and VEGF was examined in 49 advanced gastric adenocarcinomas. In addition, double immunohistochemical staining was performed using anti-CD34 and anti-Ki-67 antibodies, and the intratumoral microvessel densities and their endothelial proliferative labeling indices were then counted to evaluate the degree of angiogenesis. RESULTS: The expression of c-H-ras p21 was demonstrated in 43 out of 49 gastric adenocarcinomas (87.8%). It did not correlate with histologic type, depth of invasion or metastasis. However, the degree of c-H-ras p21 expression was correlated with VEGF. In addition, the degree of c-H-ras p21 expression was correlated with increased intratumoral microvascular density and endothelial proliferative activity. CONCLUSIONS: We suggest that c-H-ras oncogene product p21 contributes to the upregulation of tumor-associated angiogenesis by the increased production of VEGF in advanced gastric carcinomas. Therefore, treatment involving the targeting of ras oncogene could inhibit solid tumor growth by suppressing tumor-associated angiogenesis.

Adenocarcinoma↗

PubMed2000

Odontogenic ghost cell carcinoma: a case report with reference to the relation between apoptosis and ghost cells.

The neoplastic variant of calcifying odontogenic cyst has various designations, and its malignant counterpart has been reported as aggressive epithelial odontogenic ghost cell tumor or odontogenic ghost cell carcinoma. We present a case of odontogenic ghost cell carcinoma with reference to the relation between the ghost cells and apoptosis. A 33-year-old man complained of a mandibular mass. The mass occupied the entire right side of the mandible with destruction of both buccal and lingual bone. The mass also infiltrated into submandibular and sublingual spaces. Histologically, the mass was composed of a solid proliferation of hyperchromatic and pleomorphic epithelial cells with abnormal mitoses. Islands of ghost cells were frequently admixed with nucleated cells, and there were foci of ameloblastic differentiation. Immunohistochemical stains for cytokeratins, involucrin, and apoptosis-related proteins such as Bcl-2, Bcl-X(L), and Bax were done. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) assay was also performed. The nucleated cells adjacent to the ghost cells expressed cytokeratins and involucrin, but the ghost cells had no reaction. Bcl-2 was negative. Both Bcl-X(L) and Bax were demonstrated in the nucleated cells adjacent to the ghost cells. The ghost cells exhibited Bax protein. Some nucleated cells adjacent to the ghost cells were positive with TUNEL assay. The above results indicate that ghost cells undergo abnormal terminal differentiation as an apoptotic process.

Adult↗

PubMed2000

A phase II study of a daily x4 schedule of vinorelbine plus cisplatin for advanced non-small cell lung cancer.

BACKGROUND: Because dose intensity may be important as a determinant response to vinorelbine, we explored the possibility of increasing the dose intensity of vinorelbine on a daily x4 schedule. METHODS: Between February 1998 and March 1999, 31 patients with previously untreated advanced non-small cell lung cancer were enrolled. Vinorelbine 15 mg/m2 and cisplatin 20 mg/ m2 were administered intravenously daily for 4 days and repeated every 21 days. RESULTS: A total 96 cycles were administered (median 3, range 1-6); 42% of vinorelbine and 39% of cisplatin injections were dose-reduced or delayed owing to toxicity. The actual dose intensity (DI) of vinorelbine was 17.7 mg/m2/week and that of cisplatin was 24 mg/m2/week. These figures represent 88 and 90% of the theoretical DI, respectively. The overall response rate was 40% (12/30, one CR). The main toxicity was myelosuppression: granulocytopenia WHO grade 3 and 4 in 24 patients (77%) and thrombocytopenia grade 3 in two patients (6%). The non-hematological toxicity was mild and tolerable. After a median follow-up of 7.5 months (range 3-21 months), the median progression-free survival and overall survival times were 5 months (95% CI, 3.8-6.2) and 8 months (95% CI, 4.5-11.5), respectively. CONCLUSIONS: This regimen has a comparable therapeutic activity in patients with advanced lung cancers. However, despite supportive care there were excessive hematological toxicities. In view of increased toxicity and similar efficacy, this regimen is not indicated outside a clinical trial.

Adult↗

PubMed2000

Activated platelets induce secretion of interleukin-1beta, monocyte chemotactic protein-1, and macrophage inflammatory protein-1alpha and surface expression of intercellular adhesion molecule-1 on cultured endothelial cells.

Atherosclerosis is an inflammatory disease. Platelet-endothelium interaction plays an important role in the pathophysiology of atherogenesis. We investigated the role of activated platelets for secretion of interleukin (IL)-1beta, monocyte chemotactic protein (MCP)-1 and macrophage inflammatory protein (MIP)-1alpha and expression of intercellular adhesion molecule (ICAM)-1 on endothelial cells. Human umbilical vein endothelial cells (HUVEC) were incubated with non-stimulated or ADP-activated platelets for 6 hr. Secretion of interleukin (IL)-1beta, MCP-1 and MIP-1alpha and surface expression of ICAM-1 were measured by ELISA and flow cytometry. In the presence of activated platelets, the secretion of IL-1beta, MCP-1, and MIP-1alpha and surface expression of ICAM-1 were significantly increased compared with non-activated platelets. The present study shows that activated platelets may contribute to expression of various inflammatory mediators on endothelial cells.

Blood Platelets↗

PubMed2000

Management of persistent or recurrent pneumothorax with a two millimeter mini-videothoracoscope.

The aim of this study was to assess whether a 2 mm mini-videothoracoscope could be used as a conventional videothoracoscope in the management of pneumothorax. Thirty patients of ages from 15 to 35 years with recurrent or persistent pneumothorax were involved in this study. The subjects consisted of 27 males and three females. The indications for videothoracoscopic surgery were ipsilateral recurrent pneumothorax in 12 (40%), persistent air leakage in 15 (50%), visible bullae in 2 (6%), and 1 bilateral pneumothorax (3%). The mean operation time was 42.9+/-12.9 min. The average number of uses for Endo-GIA was 1.9+/-1.3 times and chest tube indwelling time was 3.8+/-2.7 days. The average amount of keptoprofen (100 mg/2 mL/ampule) used on the first postoperative day was 1.2+/-1.1 ampules. No parenteral opioids were given to the patients for pain control after the procedures. After a follow up of 8 to 20 months, there was only one recurrence among the patients. In conclusion, a 2 mm videothoracoscope, in selective cases, can be successfully used as conventional videothoracoscope to manage persistent or recurrent pneumothorax with cosmetically excellent results.

Adolescent↗

PubMed2000

Churg-Strauss syndrome with perforating ulcers of the colon.

We report a case of a 72-year-old woman with Churg-Strauss syndrome, who presented with intestinal perforation. She has had bronchial asthma with peripheral blood eosinophilia for 30 years. Gross findings of a resected colon showed multiple ulcers with perforation. Histologic findings demonstrated transmural inflammation infiltrated with large numbers of eosionophils, neutrophils and lymphoplasma cells, and characteristic extravascular granuloma in the subserosa. There were multifocally-distributed transmural vasculitis showing all stages of activity in medium and small-sized arteries and veins located in the submucosa, and proper muscle and subserosal layers of the colon, some of which revealed granulomatous inflammation. Histologic finding of liver showed chronic viral hepatitis B with mild inflammatory activity and macronodular cirrhosis. Immunohistochemical findings, acid fuschin orange G staining and electromicroscope found no evidence of hepatitis B virus infection contributing to the pathogenesis of this lesion.

Aged↗

PubMed2000

Metastatic renal cell carcinoma in a meningioma: a case report.

Tumor-to-tumor metastasis is rare. We report a case of metastatic renal cell carcinoma in meningioma. A 67-year-old woman presented a two-week history of motor dysphagia and decreased short-term memory. She had undergone a left radical nephrectomy for a renal cell carcinoma 7 years ago, and had not received any adjuvant therapy. MRI disclosed a 3.0 x 3.0 x 3.0-cm sized round tentorial-based extraaxial mass with peritumoral edema in the left posterior temporal lobe. During operation, the tumor was found to be an encapsulated mass firmly attached to the tentorium. Histologically, the tumor was a meningotheliomatous meningioma extensively infiltrated by metastatic renal cell carcinoma, accompanying widespread coagulative necrosis. Immunohistochemical staining for cytokeratin revealed strong positivity only in the renal cell carcinoma component. The patient's postoperative course was uneventful. Post-operative radiation therapy was applied to the whole brain. Three months after operation, the patient developed right hemiparesis and dysphagia. Brain MRI at that time did not reveal recurrence or any other causative lesions, although the whole body scan disclosed uptake at the second lumbar vertebra and rib. The patient refused further treatment.

Aged↗