BACKGROUND: Methicillin-resistant Staphylococcus aureus(MRSA) is an increasingly common cause of nosocomial infections worldwide. Epidemiologic investigation of MRSA outbreaks and identification of pathways of nosocomial MRSA spread require the ability to distinguish individual MRSA strains. We applied molecular tap ing of the methicillin-resistant determinant (mec) and coagulase typing in the investigation of a nosocomial MRSA infections. METHODS: We randomly selected 79 strains of mecA positive MRSA isolated from patients who visited Dong-A university Hospital from Dec. 1995 to Oct. 1996. Molecular typing of MRSA was performed by comparing the size of the mac-associated hypervariable region amplified by the polymerase chain reaction (PCR). Coagulase typing with type I-VIII antisera was also used for classification of MRSA based on its phenotype. Each isolates were classified by the combination of molecular analyses and coagulase type. RESULTS: The 79 MRSA isolates were grouped Into sin hypervariable legion (HVR) genotypes on the basis of the size of the PGR products. In coagulase typing, the most predominant type was II(46.8%) and type V was not found. Nine strains were not typable. The combination of HVR genotypes and coagulase types showed 23 different types in 79 MRSA Isolates. The strains which were repeatedly isolated from the same patients showed the same HYR genotypes and coagulate types. CONCLUSION: The combination of HVR genotypes and coagulase types is thought to be useful in epidemiolgical Investigation of nosocomial infections caused by MRSA ,because of its simplicity and reproducibility.
Classification ; Coagulase* ; Cross Infection* ; Disease Outbreaks ; Genotype ; Humans ; Immune Sera ; Methicillin Resistance* ; Methicillin-Resistant Staphylococcus aureus* ; Molecular Typing* ; Phenotype ; Polymerase Chain Reaction ; Staphylococcus

BACKGROUND: Recent DNA polymorphism analysis using numerous DNA markers has been used to determine the parental origin of the extra chromosome 21 in Down syndrome. In this study we used seven dinucleotide repeat polymorphisms on chromosome 21 to characterize a case of rea(21q21q) and to know whether it is consistent with an isochromosome or a true Robertsonian translocation. METHODS: Cytogenetic investigation was done by conventional G banding DNA was extracted from whole blood of a proband and her parents and was amplified by PCR using seven sets of (GT)n repeat dinucleotide markers located on the long arm of chromosome 21 After electrophoresis of the PCR product in polyacrylamide gel and silver staining the parental origin and number of DNA copy were determined by visual comparison of the band intensities within and between individuals. RESULTS: Conventional cytogenetics showed that the proband had a 46.XX.re(21q21q) chromosome pattern. Parental chromosome studies were normal, therefore, the rearrangement was a de novo event. All seven DNA markers showed one or two alleles, demonstrating rea(21q21q) to be an isochromosome. For D21S215 and D21S156 markers both parents were heterozygous and the proband inherited one copy of paternal allele and two copies of maternal allele which both parents did not share. This finding was consistent with a maternally derided isochromosome. CONCLUSION: Use of dinucleotide repeat DNA polymorphisms after PCR amplification will be very useful to detect the parental origin of additional chromosome 21 or rearrangement of chromosome 21 in Down syndrome. Besides employing siltier staining of a PCR product we will be able to avoid using of radioisotopes and apply to clinical laboratory diagnosis.
Alleles ; Arm ; Chromosomes, Human, Pair 21 ; Clinical Laboratory Techniques ; Cytogenetics ; Dinucleotide Repeats* ; DNA ; Down Syndrome ; Electrophoresis ; Genetic Markers ; Humans ; Isochromosomes ; Parents ; Polymerase Chain Reaction ; Radioisotopes ; Silver Staining

BACKGROUND: Recently, a great deal of interest has been focused on the use of hydroxyurea and hemin that may augment Hb F levels in patients with hemoglobinopathies and thalassemia, although the molecular mechanism of those chemicals remains unclear. In this study, we examined the effects of hydroxyurea and hemin on human adult peripheral and cord blood erythroid cells grown in a two-phase liquid culture system. METHODS: Four adult peripheral and four cord blood cells were cultured in two-phase liquid culture, and were treated with hydroxyurea or hemin. We counted isolated erythroid cells by acid benzidine and glycophorin A stains. To determine whether transcription factor binding to the promoter is critical, we also examined the promoter region of gamma globin gene both under uninduced and hydroxyurea or hemin induced conditions using gel mobility shift assay and southwestern blot analysis. RESULTS: When added together with erythropoietin, hydroxyurea led to significant increase in the percentage of erythroid cells in cord blood. In contrast, hemin greatly accelerated hemoglobin accumulation in adult erythroid progenitor cells. At -230 and -264 regions of gamma globin gene promoter, different protein binding patterns were observed in uninduced and hydroxyurea or hemin induced conditions between adult and cord blood. CONCLUSIONS: These results suggest that hydroxyurea and hemin may act via alteration in DNA-protein interactions to induce gamma globin gene expression. In addition, we can conclude that different transcription factors may be involved in the gamma globin induction process between the adult and cord blood erythroid cells.
Adult ; Blotting, Southwestern ; Coloring Agents ; Electrophoretic Mobility Shift Assay ; Erythroid Cells ; Erythroid Precursor Cells* ; Erythropoietin ; Fetal Blood ; gamma-Globins* ; Gene Expression ; Glycophorin ; Hemin ; Hemoglobinopathies ; Humans ; Hydroxyurea* ; Promoter Regions, Genetic* ; Protein Binding ; Thalassemia ; Transcription Factors

BACKGROUND/AIMS: Hepatocytes on the hepatic lobule mipate from portal zone to centrilobular mea as the DNA synthesis within it. And also, the xenobiotic reactions reveal characteristic differences associated with zone specific metabolism in the liver acinus. In this study, the zonal distribution of ethylnitrosourea (ENU)-induced hepatic precancerous lesion was stereologically investigated. METHODS: Nine B6C3F1 mices were given I.p. injection of ENU (60 ug/pn body weight) when the pups were 15 days old prior to sacrifices at 8 weeks of life. All the 150 consecutive sections, 3 p m in thickness, were stained with hematoxylin and eosin and identified the basophilic precancerous lesions with 80-165 p m diameter in equatorial plane by the Zeiss microprojector. And then the distances from the center of selected foci to terminal hepatic vein or portal vein branches were estimated under the microscopic fields. As a control group, the same estimations were performed from the random points by the appointments of random digit table. RESULTS: Mean distance between ENU-induced 52 hepatocellular foci and the nearest terminal hepytic vein was 181.15+112.39 p m (Mean+ SD), but that of randomly selected 104 points was 291.73+157.98pm (Mean+5D) (Students t-test, p<0.0005). Substantially, 52.7% of ENU-induced 52 hepatocellular foci were within 300 p m from the terminal hepatic vein, but randomly selected 104 points were only 50.9% (Shapiro Wilk W test, w=0.819857, p=0.048038). Mean distance from ENU-induced 52 foci to portal vein was 398.85+149.98pm (Mean+SD), but that from the randomly selected 104 points was 315.87+145.79 pm (Mean+SD)(Students t-test, p<0.0005). CONCLUSION: Stereologically, ENU-induced mice liver cell foci distribute non-randomly to Zone III, centrilobular zone of mouse hepatic acini where promote invasion toward terminal hepatic veins.
Animals ; Appointments and Schedules ; Basophils ; Cholestasis ; DNA ; Eosine Yellowish-(YS) ; Ethylnitrosourea ; Fluconazole ; Hematoxylin ; Hepatic Veins ; Hepatocytes ; Liver ; Metabolism ; Mice* ; Portal Vein ; Veins

PURPOSE: This study was aimed at assessing the difference of the prevalence of iron deficiency and iron deficiency anemia among rural and urban middle school students in relation to dietary habit. METHODS: With a questionnaire, blood samples were obtained from 439 apparently healthy rural and urban middle school students residing in Ulsan. Anemia was defined as hemoglobin level of 12.6 g/dL or less for boys and 11.9 g/dL or less for girls. Iron deficiency was defined as serun ferritin level less than 12 micrograms/L or/and transferrin saturation less than 14%. Iron deficiency anemia was defined as iron deficiency plus low hemoglobin. RESULTS: 1) In boys, the prevalence rate of anemia was 17.2%. Among these anemias, 5.4% were found to be iron deficiency anemia. In girls, the prevalence of anemia increased with age. The prevalence of iron deficiency anemia was 6.9%. 2) In girls, the prevalence rate of anemia in rural area was higher than that of anemia in urban area (12.6% in rural, 6.1% in urban, P<0.01). 3) The prevalence of anemia and iron deficiency in the students with menstruation was 10.6% and 33.1%, which was higher than the prevalence of 2.5% and 7.5% in those who did not have the menarche (P<0.001 and P<0.001, respectively). 4) Dietary intake of rural and urban middle school students was estimated lower in energy, iron than the recommeded dietary allowance (RDA). In girls, dietary intake of rural middle school students was estimated lower in iron, niacin, and vitamin C than that of urban middle school students. 5) Nutritional factors such as energy, carbohydrate, protein, and phosphorus showed positive correlation with RBC, hemoglobin (P<0.05). CONCLUSION: It is recommended to enforce the nutritional education to take enough iron in middle school students to reduce the high prevalence rate of anemia among pubertal students.
Anemia* ; Anemia, Iron-Deficiency ; Ascorbic Acid ; Education ; Female ; Ferritins ; Food Habits ; Humans ; Iron* ; Menarche ; Menstruation ; Niacin ; Phosphorus ; Prevalence ; Surveys and Questionnaires ; Transferrin ; Ulsan*

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 0.1x10(6)-1.0x10(6)/mL with a purity of 84.0-97.3%. Hb F stain showed total erythroid cells of approximately 0.4x10(4)-9.8x10(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/methods ; Cell Separation/*methods ; Chromosome Abnormalities/diagnosis ; *Erythroblasts ; Female ; Genetic Screening ; Human ; *In Situ Hybridization, Fluorescence ; Karyotyping ; *Maternal-Fetal Exchange ; Pregnancy ; sPrenatal Diagnosis/*methods

Dental clinicians and researchers have recently recommended oral microbial examinations to more accurately diagnose and treat oral diseases, including periodontitis and dental caries. Theoretical and experimental evidence suggests that oral microbiota may also be associated with non-oral diseases, such as gastrointestinal and extra-gastrointestinal diseases. This review highlights studies demonstrating microbial alterations in the oral cavity associated with malignant tumors including gastric, colorectal, esophageal, and lung cancers, implying that these alterations may serve as early indicators for non-invasive diagnosis and risk assessment of cancer development. Furthermore, we addressed the implications of oral microbial co-occurrence with malignant tumors, such as Streptococcus anginosus, Fusobacterium nucleatum, and Veillonella parvula, which are recognized as tumor-enriched oral pathogens involved in the development and progression of cancers in the stomach, colon, and lungs, respectively. Notably, we explored the immune and inflammatory mechanisms underlying reciprocal interactions between oral microbiota and tumors, underscoring that targeting these mechanistic pathways can contribute to preventing cancer development.

Dental clinicians and researchers have recently recommended oral microbial examinations to more accurately diagnose and treat oral diseases, including periodontitis and dental caries. Theoretical and experimental evidence suggests that oral microbiota may also be associated with non-oral diseases, such as gastrointestinal and extra-gastrointestinal diseases. This review highlights studies demonstrating microbial alterations in the oral cavity associated with malignant tumors including gastric, colorectal, esophageal, and lung cancers, implying that these alterations may serve as early indicators for non-invasive diagnosis and risk assessment of cancer development. Furthermore, we addressed the implications of oral microbial co-occurrence with malignant tumors, such as Streptococcus anginosus, Fusobacterium nucleatum, and Veillonella parvula, which are recognized as tumor-enriched oral pathogens involved in the development and progression of cancers in the stomach, colon, and lungs, respectively. Notably, we explored the immune and inflammatory mechanisms underlying reciprocal interactions between oral microbiota and tumors, underscoring that targeting these mechanistic pathways can contribute to preventing cancer development.

Dental clinicians and researchers have recently recommended oral microbial examinations to more accurately diagnose and treat oral diseases, including periodontitis and dental caries. Theoretical and experimental evidence suggests that oral microbiota may also be associated with non-oral diseases, such as gastrointestinal and extra-gastrointestinal diseases. This review highlights studies demonstrating microbial alterations in the oral cavity associated with malignant tumors including gastric, colorectal, esophageal, and lung cancers, implying that these alterations may serve as early indicators for non-invasive diagnosis and risk assessment of cancer development. Furthermore, we addressed the implications of oral microbial co-occurrence with malignant tumors, such as Streptococcus anginosus, Fusobacterium nucleatum, and Veillonella parvula, which are recognized as tumor-enriched oral pathogens involved in the development and progression of cancers in the stomach, colon, and lungs, respectively. Notably, we explored the immune and inflammatory mechanisms underlying reciprocal interactions between oral microbiota and tumors, underscoring that targeting these mechanistic pathways can contribute to preventing cancer development.

Dental clinicians and researchers have recently recommended oral microbial examinations to more accurately diagnose and treat oral diseases, including periodontitis and dental caries. Theoretical and experimental evidence suggests that oral microbiota may also be associated with non-oral diseases, such as gastrointestinal and extra-gastrointestinal diseases. This review highlights studies demonstrating microbial alterations in the oral cavity associated with malignant tumors including gastric, colorectal, esophageal, and lung cancers, implying that these alterations may serve as early indicators for non-invasive diagnosis and risk assessment of cancer development. Furthermore, we addressed the implications of oral microbial co-occurrence with malignant tumors, such as Streptococcus anginosus, Fusobacterium nucleatum, and Veillonella parvula, which are recognized as tumor-enriched oral pathogens involved in the development and progression of cancers in the stomach, colon, and lungs, respectively. Notably, we explored the immune and inflammatory mechanisms underlying reciprocal interactions between oral microbiota and tumors, underscoring that targeting these mechanistic pathways can contribute to preventing cancer development.