Comparative Reactivity of 2 TU and 5 TU PPD Skin Tests

PURPOSE: These days 5 TU purified protein derivative (PPD) is substituted with 2 TU PPD for the tuberculin skin test, a test essential in the diagnosis of tuberculosis in pediatric population. However, there had been no adequate criteria for the positivity of 2 TU PPD skin test. This study was performed to clarify the criteria of positive reactivity of 2 TU PPD skin test. The reactivity of 2 TU PPD was compared to that of 5 TU PPD. METHODS: One hundred and six medical students were tested with Mantoux method. Diameters of induration were measured 72 hours after the intradermal injections of 2 TU and 5 TU PPDs. Past history and family history of tuberculosis, history of BCG administration and the presence of BCG scar were recorded. RESULTS: One hundred and three subjects completed the study. Mean diameter of 2 TU tuberculin test was 10.3 mm and that of 5 TU test was 14.4mm, which was significantly different (P<0.001). The diameters were 0-24mm in the 2 TU test and 0-25mm in the 5 TU test. The diameter of induration in 2 TU test was positively correlated to that in 5 TU test (r2=0.63). Eighty-six subjects (83.5%) in the 2 TU test and 92 subjects (89.3%) in the 5 TU test had diameters of induration of 5mm or more; 59 (57.3%) subjects in the 2 TU test and 83 (80.6%) subjects in the 5 TU test had diameters of induration of 10 mm or more; 27 (26.2%) in the 2 TU test and 64 (62.1%) in the 5 TU test had diameters of induration of 15mm or more. Seventy-six of 103 subjects (73.7%) had greater diameters of induration in 5 TU test than in 2 TU, 22 (21.4%) had the same diameters, and 5 (4.9%) had greater diameters of induration in 2 TU test than in 5 TU test, and the last 5 subjects had indurations of more than 10mm diameter in both 2 TU and 5 TU tests. CONCLUSION: The criterion of positivity in 2 TU PPD skin test, essential for the diagnosis of tuberculosis, is different from that in 5 TU test. In this study, 6 mm or more was adequate for the criterion of positivity and 10mm or more for the criterion of strong positivity. Further studies should be done to establish a criterion for the pediatric population.

Inhibition of Overexpression of c-myb Protooncogene in K562 Cells Using c-myb Antisense Oligodeoxynucleotides / 대한소아혈액종양학회지

PURPOSE: The c-myb protooncogene encodes MYB protein that is critical for normal and leukemic hematopoietic cell proliferation and development. It is known that c-myb plays an important role in leukemogenesis as well. Aberrant expression of c-myb is seen in acute myeloid leukemia (AML), acute lymphoid leukemia (ALL), and chronic myeloid leukemia (CML). We reasoned that down regulation of c-myb expression using synthetic antisense oligomers targeted to c-myb mRNA might prove useful antileukemic agents if leukemia cells were more dependent on c-myb function for proliferation than their normal counterparts. To investigate the applying possibility of c-myb antisense oligodeoxynucleotides as the useful antileukemic agents, we examined the cell viability, cloning efficiency and the expression of c-myb mRNA and MYB protein after the exposure of c-myb oligomers on normal bone marrow cells and leukemia cells. MATERIALS AND METHODS: We maintained in short-term suspension culture for 4 days to analyze the effect of c-myb oligomers on normal bone marrow cells and chronic myelocytic leukemia cell line K562. During suspension culture, cell counts and viability were periodically determined, and immediately seeded into duplicate methylcellulose cultures containing recombinanat human interleukin 3 and GM-CSF. Cells placed in semisolid cultures were allowed to grow for an additional 10~12 days. We counted the colonies, and then RNA and protein was extracted from cells cloned in liquified methyl- cellulose cultures. We detected the c-myb mRNA expression by RT-PCR and Southern hybridization analysis and MYB expression by Western hybridization analysis. RESULTS: c-myb sense oligomers had negligible effects on K562 cells growth in short- term suspension culture, while exposure to c-myb antisense oligomers resulted in a daily decline in cell number. In contrast, normal bone marow cell viability and numbers were unaffected by c-myb sense or antisense oligomers exposure. c-myb antisense oligodeoxy nucleotides strongly inhibited or completely abolished growth and colony formation of K562 cells. In contrast, c-myb sense oligomers did not affect. At antisense dose that inhibited leukemic cell growth, normal bone marrow cells survived. Thus, normal and leukemic cells showed the differential sensitivity to the toxic effect of c-myb antisense oligomers. RT-PCR, Southern hybridization analysis and Western hybridization analysis of c-myb antisense-treated K562 cells revealed a complete absence of c-myb mRNA expression and MYB expression. CONCLUSION: Results obtained from these studies suggest that inhibition of c-myb function with antisense oligodeoxynucleotides might eventually form the basis for a molecular biologic approach to leukemia therapy, perhaps most immediately as ex vivo bone marrow purging agent.

A Case of Lipoblastoma Presented with Respiratory Symptom / 소아알레르기및호흡기학회지

Lipoblastoma is a variant of lipoma and lipomatosis occuring almost exclusively during the years of infancy and early childhood. These lesions differ from lipoma and lipomatosis by their cellular immaturity and their close resemblance to the myxoid form of liposarcoma. We experienced one case of lipoblastoma in 21 months old boy who suffered from respiratory tract symptoms such as cough, sputum production, and mild fever. At first he was misdiagnosed pneumonia and treated with antibiotics and conservative management for pneumonia. Later he was rediagnosed as tumor in the left upper lung. For removal of tumor he had operative excision and the biopsies were showed compatible to lipoblastoma. A brief review of related literatures is also presented.

A Case of Congenital Megacalyces

Congenital megacalyces is a congenital renal disease characterized by hypoplasia of the medulla and a non-obstructive dilatation of the calyces. More than 100 cases have been reported in the literature after first described by Puigvert in 1963, but it has been reported only three cases (two cases of adults and one case of child) in the literatures in Korea. The etiology of the congenital megacalyces is unknown. Renal pelvis and ureter are mostly normal in size and there is no urinary obstruction or reflux. Renal medulla of congenital megacalyces is thinner than that of normal kidney but renal cortex retains its normal thickness and function. This is features that help to distinguish megacalyces from obstructive atropy. The calyces are polygonal in shape and the majority of kidney with megacalyces have increased number of calyces. Since congenital megacalyces is a non-progressive lesion, it is important to recognize the clinical entity and avoid unnecessary surgery. We report one case of congenital megacalyces without urinary obstruction or reflux with a brief review of related literatures.