Germline mutations of the dpc4 gene in Korean juvenile polyposis patients

Juvenile polyposis is an uncommon condition characterized by the development of multiple (usually more than 5) juvenile polyps in the gastrointestinal tract, especially in the colon. This disease usually occurs during childhood, and is inherited in an autosomal dominant fashion. It has been suggested that the dpc4 (deleted in pancreatic carcinoma, locus 4) gene, which is located on chromosome 18q21.1, might cause juvenile polyposis. The dpc4 (smad4) gene is a candidate tumor-suppressor gene and may play a role in the TGF-beta-signaling pathway. To confirm the idea that alterations of the dpc4 gene may result in juvenile polyposis, we screened 5 Korean juvenile-polyposis patients by PCR-SSCP (single-strand conformation polymorphism) analysis and bi-directional sequencing. There were germline mutations of the dpc4 gene in 3 out of the 5 patients: 2 had a genetic alteration in exon 9 and the third had a mutation in exon 8. These germline mutations occurred in the C-terminus of the dpc4 gene, similar to most published mutations. One patient exhibited a non-sense mutation (codon 388), which changed a glutamine codon (CAG) to a stop codon (TAG). The second patient harbored a mis-sense mutation (codon 390), causing a non-conservative amino-acid change . The third patient had a mis-sense mutation in exon 8 (codon 361), which altered an arginine codon (CGC) into a histidine codon (CAC).     

Size assessment of adenoid and nasopharyngeal airway by acoustic rhinometry in children

Adenoid hypertrophy is known as the most common cause of nasal obstruction in children; thus, adenoidectomy with, or without, tonsillectomy is one of the most commonly performed surgical procedures in the paediatric population. Although many methods have been suggested, few studies have reported on how to assess adenoid size, pre-operatively. Acoustic rhinometry is an objective technique as well as a non-invasive method, which can be easily used in young children. This study confirmed that acoustic rhinometry is a non-invasive and objective technique for assessing the geometry of the nasal cavity and nasopharynx. Forty children were evaluated using symptomology, two different radiological measurements and acoustic rhinometry; the results were compared with endoscopic findings. Clinical symptoms and A/N ratio measured with Fujioka's method significantly correlated with the endoscopic assessment findings (r = 0.769 and 0.604 respectively). Significant increases in the cross-sectional area and volume of the nasopharynx were observed at the adenoid notch after adenoidectomy (p < 0.005 and p < 0.005, respectively). Acoustic rhinometry showed a high degree of correlation of which adenoid occupied the nasopharyngeal airway under endoscopic examination (r = 0.771). Thus, the study concluded that acoustic rhinometry can be as good an objective method for measuring adenoid sizes as endoscopy and can be used as one of the pre-operative examination tools for adenoidectomy.     

Enhanced Hatching Rate of Bovine IVM/IVF/IVC Blastocysts Using a 1.48-μm Diode Laser Beam

Purpose: Our purpose was to test whether zona pellucida (ZP) drilling using a 1.48-m diode laser beam on bovine IVM/IVF/IVC blastocysts is effective for embryo hatching. Methods: Blastocysts produced in vitro at day 7 after IVF were divided into control and laser-drilled groups, respectively. Results: When the rates of in vitro development of bovine embryos were examined, the average cleavage rate (>two-cell) was 82.3% and the blastocyst rate at day 7 after IVF was 32.5%. Using these blastocysts, when the laser drilling effect was investigated at 48 hr after treatment, the total hatching rate in the laser-drilled group (98.0%) was significantly higher than that in the control group (60.0%)(P < 0.001). Especially, the hatched rate of the laser-drilled group (68.0%) was significantly enhanced compared with that of the control group (30.0%) (P < 0.001). Conclusions: These results demonstrated that laser ZP drilling on bovine IVM/IVF/IVC blastocysts can significantly increase the hatching rate.     

Leukemic cell line, KG-1 has a functional loss of hOGG1 enzyme due to a point mutation and 8-hydroxydeoxyguanosine can kill KG-1

We tested the cytotoxic action of 8-hydroxyguanine (8ohG) by observing the viability of several leukemic cell lines (KG-1, U937, Jurkat and K 562) in the presence of 8-hydroxydeoxyguanosine (8ohdG), a nucleoside of 8ohG. It was found that 8ohdG showed cytotoxic action only to KG-1 and that only KG-1 showed a homozygous arginine 209 to glutamine mutation in the hOGG1 gene with an almost negligible hOGG1 enzyme activity. Possibly, the selective cytotoxicity in 8ohdG to KG-1 may be due to its low capacity to cope with an increase in the 8ohG level in DNA resulting from the incorporation of 8ohdG present in the culture media. The mutational impairment of hOGG1 in KG-1 is the first report in leukemic cell lines. Using KG-1 with impaired hOGG1, we demonstrated cytotoxicity of 8ohdG probably due to its incorporation into cellular DNA. This new property of KG-1 may allow it to serve as an useful tool for studies of OGG1, oxidative DNA damage and the cytotoxic action of 8ohG. Oncogene (2000) 19, 4476 - 4479.     

The expression of MHC class I, TAP1/2, and LMP2/7 gene in human gastric cancer cell lines

Intracellular antigens are presented to CD8+ T cells through major histocompatibility complex (MHC) class I molecule. For stable MHC class I expression, several molecules as well as the MHC molecule itself have to express simultaneously and function well. To determine a gene associated with MHC class I surface expression, the expressions of LMP2/7 and TAP1/2 including MHC I gene were analyzed in ten human gastric cancer cell lines, using RT-PCR and Northern blot analysis. Although LMP2, TAP1/2, and MHC class I gene expression were reduced in some cells, this was not significantly associated with MHC class I surface expression. By comparison, the expression of LMP7 was significantly reduced in three of ten cell lines, which also showed low levels of MHC class I surface expression, and increased in four of ten cell lines, which also showed high levels of MHC class I surface expression. These results suggest that the level of MHC class I surface expression is associated, in most cases, with the expression of the LMP7 gene regardless of the LMP2, TAP1, TAP2, or MHC class I genes.     

The Protective Effects of Lactoferrin Feeding against Endotoxin Lethal Shock in Germfree Piglets

The unique germfree, colostrum-deprived, immunologically “virgin” piglet model was used to evaluate the ability of lactoferrin (LF) to protect against lethal shock induced by intravenously administered endotoxin. Piglets were fed LF or bovine serum albumin (BSA) prior to challenge with intravenous Escherichia coli lipopolysaccharide (LPS), and temperature, clinical symptoms, and mortality were tracked for 48 h following LPS administration. Prefeeding with LF resulted in a significant decrease in piglet mortality compared to feeding with BSA (16.7 versus 73.7% mortality, P < 0.001). Protection against the LPS challenge by LF was also correlated with both resistance to induction of hypothermia by endotoxin and an overall increase in wellness, as quantified by a toxicity score developed for these studies. In vitro studies using a flow cytometric assay system demonstrated that LPS binding to porcine monocytes was inhibited by LF in a dose-dependent fashion, suggesting that the mechanism of LF action in vivo may be inhibition of LPS binding to monocytes/macrophages and, in turn, prevention of induction of monocyte/macrophage-derived inflammatory-toxic cytokines.     

Sonographic findings of intestinal tuberculosis

Sonograms in 41 patients with intestinal tuberculosis were analyzed. The sonographic findings of intestinal tuberculosis were thickening of the wall in the ileum, cecum, or ascending colon (or in more than one of these). We detected the wall thickening in 38 cases by sonography (detection rate, 93%). The ileum was the most frequent site of involvement. The patterns of bowel wall thickening were diffuse in 30 cases and focal in eight cases and were concentric in 28 cases and eccentric in six cases. The associated findings were ascites, lymphadenopathy, omental cake, and cecal spasm in order of decreasing frequency. The sonographic findings are not specific for the diagnosis of intestinal tuberculosis, but when noted in the appropriate clinical situation would be of great help in the diagnosis of intestinal tuberculosis.