Kwangchul Lee

Clinical and hematologic manifestations in patients with Diamond Blackfan anemia in Korea.

Background Diamond Blackfan anemia (DBA), characterized by impaired red cell production, is a rare condition that is usually symptomatic in early infancy. The purpose of this study was to assess nationwide experiences of DBA encountered over a period of 20 years. Methods The medical records of 56 patients diagnosed with DBA were retrospectively reviewed from November 1984 to July 2010. Fifteen institutions, including 13 university hospitals, participated in this study. Results The male-to-female ratio of patients with DBA was 1.67:1. The median age of diagnosis was 4 months, and 74.1% were diagnosed before 1 year of age. From 2000 to 2009, annual incidence was 6.6 cases per million. Excluding growth retardation, 38.2% showed congenital defects: thumb deformities, ptosis, coarctation of aorta, ventricular septal defect, strabismus, etc. The mean hemoglobin concentration was 5.1±1.9 g/dL, mean corpuscular volume was 93.4±11.6 fL, and mean number of reticulocytes was 19,700/mm3. The mean cellularity of bone marrow was 75%, with myeloid:erythroid ratio of 20.4:1. After remission, 48.9% of patients did not need further steroids. Five patients with DBA who received hematopoietic transplantation have survived. Cancer developed in 2 cases (3.6%). Conclusion The incidence of DBA is similar to data already published, but our study had a male predilection. Although all patients responded to initial treatment with steroids, about half needed further steroids after remission. It is necessary to collect further data, including information regarding management pathways, from nationwide DBA registries, along with data on molecular analyses.

Plastic limit loads for thick-walled branch junctions

This technical note extends the validity of limit load solutions for thin-walled branch junctions, previously proposed by the current author, to thick-walled cases. It is achieved simply by re-normalizing the thin-wall expressions by the limit loads of thick-walled tubes instead of those of thin-walled tubes. Comparison with finite element results shows overall good agreement.

Effect of local wall thinning on limit loads for piping branch junctions. Part 2: In-plane bending

This paper presents plastic limit loads of piping branch junctions with local wall thinning under in-plane bending, based on systematic three-dimensional finite element (FE) limit analyses using elastic—perfectly plastic materials. As in Part 1, an ideal branch junction without weld or reinforcement around the intersection is considered with two locations of wall thinning; one in the run pipe (opposite to the intersection), and the other in the branch pipe (next to the intersection). Based on FE results, effects of thinning geometries on plastic limit moments are quantified and simple approximations of plastic limit loads for piping branch junctions with local wall thinning under in-plane bending are proposed.

Effect of local wall thinning on limit loads for piping branch junctions. Part 1: Internal pressure:

This paper presents plastic limit pressures of piping branch junctions with local wall thinning, based on systematic three-dimensional finite element (FE) limit analyses using elastic—perfectly plastic materials. An ideal branch junction is considered, where no weld or reinforcement around the intersection is considered. Two locations of wall thinning are considered: one is in the run pipe (opposite to the intersection) and the other is in the branch pipe (next to the intersection). Based on the assumption of possible plastic collapse modes, approximate plastic limit pressure solutions for piping branch junctions with local wall thinning are proposed using two limit pressure solutions: plastic limit loads for straight pipes with local wall thinning and those for branch junctions without wall thinning. Comparison with FE results shows overall good agreement.

50 Utility of Rapid B-Type Natriuretic Peptide Assay for Diagnosis of Symptomatic Patent Ductus Arteriosus in Preterm Infants

50 Utility of Rapid B-Type Natriuretic Peptide Assay for Diagnosis of Symptomatic Patent Ductus Arteriosus in Preterm Infants

Overall Outcome of Kawasaki Disease

To assess the overall outcome of Kawasaki disease, patients with a discharge diagnosis of Kawasaki disease at Korea University Medical Center from 1999 to 2001 were retrospectively evaluated. A total of 99 patients were diagnosed. The American Heart Association (AHA) criteria were met in 65 patients (66%) and 63 of them received intravenous immune globulin (IVIG, 2g/kg). Fifty patients responded afebrile within 5 days (IVIG-responsive) and 13 patients did not (IVIG-non-responsive). Within 2 months, 2 patients in the IVIG-responsive group developed coronary abnormalities compared to 3 patients in the IVIG-non-responsive group (4% vs 23%). None of whom met AHA criteria and did not received IVIG were febrile more than 5 days nor developed coronary abnormalities. In 34 patients who did not meet complete AHA criteria, 28 patients received IVIG and 25 patients were IVIG-responsive. Coronary abnormalities were developed in 4 in the IVIG-responsive group compared to none in the IVIG-non-responsive group (16% vs 0%). All 6 patients who did not meet complete AHA criteria and did not received IVIG were febrile more than 5 days and 2 of them developed coronary abnormalities. Taken together, coronary abnormalities were developed in 9 patients of 91 who were treated with IVIG compared to 2 patients of 8 who were not treated with IVIG (10% vs 25%). In conclusion coronary abnormalities were developed in 11 of 99 patients with Kawasaki disease (11%).