The toxic action of benzene on erythropoiesis and myelopciesis, has been recognized since the early years of the present century. With the advance in high civilization and modern covenience, benzene as a kind of aromatic compound has been used for industrial solvent and its longstanding use has committed a public nuisance to be overcome by medical approach. Chromosomal breakage and rearrangement may be produced by radiation, radiomimetics, virus infection and various chemicals, especially, antibiotics and antitumor agent, causing chroimosomal rearrangement in vitro, whose teratogenic action in rats was previously demonstrated. Several works hsve been published on the chromosome damage as a consequence of benzene intoxication. Recently, it was shown by certain workers that individuals who had been exposed to atmospheric benzene, even without haematological disorders, might have an elevated percentage of structural chromosome aberrations in the lymphocytes cultured from their peripheral blood. Moreover, structural and numerical chromosome aberrations were demons trated in patients with blood disorders which were believed to be due to exposure to beuzene vapors. Accordingly, much interest has been paid to its cytologic effect on the hematopoietic tissues in man and experimental animals. A high incidence of chromosomal aberrations has also been found in rabbits exposed to benzene during a period of peripheral pancytopenia and after hematologic recovery. The significance of these findings was discussed in relation to leukemic transition and to their diagnostic value in human benzene intoxication. Chromosomal anomalies can also be induced by benzene given subcutaneously to rata. A pronounced individual variation of the degree of chromosome damage was shown. The purpose of this investigation was to determine whether benzene could a direct effect on the chromosome complement of mammalian bone marrow cells in vivo and whether characteristic banding patterns might be demonstrated in rat chomosomes by a modified trypsin-Giemsa method. Four-week old Sprague-Dawley strain rats of both sexes(each weighing about 50gm) were used for this experimental study. Three groups of animals were treated-with subcutaneous infections of pure benzene. Group I received benzene, 2.0ml per kg body weight, 24 hours before sacrifice; Group II, 48 and 24 hours and Group III, 72, 48 and 24 hours. A control group was given no treatment. The animais were sacrificed in ether anesthesia. Femur and iliac bone marrow cells were suspended in medium 199 within 30 minutes and transferred to warm Hanks-distilled water(1:3) for hypotonic treatment(10 minutes). A freshly prepared solution of methanol glacial acetic acid (3:1) was used as fixative. Finally, a few drops of the cell suspension were placed on moistened, pre-cleaned slides being dried by rapid-drying technique. The slides were stained with either simple Giemsa or trypsin Giemsa banding technique. From the data obtained, this report was summarized as follows: 1. For the benzene-treated groups, chromosomal aberration rate was 13.4% in group II and 38.6% in group III, while in the controls the rate was 6.4 percent. 2. Numerical aberrations included aneuploidy, polyploidy and monoploidy. The most frequent type was hypodiploidy (5.8–9.4%) in all the treated groups. 3. Structural aberrations could be divided in gaps, ring chromosomes, breaks, deletions, exchanges and dicentrics. Among those, the majority of abnormal metaphases was gaps; 2.4%, 2.2% and 10.8% in group I, II and III respectively, and 1. 6% in control group. 4. The translocations and dicentrics were not demonstated in group I and II. 5. The normal chromosome set of the Sprague-Dawley rat was comprised of 42 chromosomes: 20 pairs of autosomes, and one pair of sex chromosomes, xx or XY chromosomes. The total number of major bands in s chromosome complement was about 40 and minor bands, 13, 6. Sucessful demonstration of banding patterns was available by proper adjustment of the concentration, temperature and duration of trypsin solution.
Acetic Acid ; Anesthesia ; Aneuploidy ; Animals ; Anti-Bacterial Agents ; Benzene ; Body Weight ; Bone Marrow Cells ; Bone Marrow ; Chromosome Aberrations ; Chromosome Breakage ; Civilization ; Complement System Proteins ; Erythropoiesis ; Ether ; Femur ; Humans ; In Vitro Techniques ; Incidence ; Lymphocytes ; Methanol ; Methods ; Pancytopenia ; Polyploidy ; Rabbits ; Rats ; Rats, Sprague-Dawley ; Ring Chromosomes ; Sex Chromosomes ; Trypsin

BACKGROUND: Endocrine pancreas tumor is a rare disease which incidence is less than 2% of all pancreatic tumors. But it comprises various types of tumor and usually secretes several hormones from one type of tumor although the patient with this tumor complains of sole symptom associated with only one hormone. The mechanism and clinical significance of multiple hormone secretion in the endocrine pancreas tumom are not yet clearly defined. METHODS: We analyzed retrospectively the clinicopathologic features of 20 cases which were operated at Seoul National University Hospital during the period between February 1989 and May 1998. RESULTS: The most common tumor was insulinoma (13 cases) and the second most common tumor was nonfunctioning tumor (6 cases). There was one case of somatostatinoma. Most of the patients with insulinoma complained of neuroglycopenic symptoms. There were 9 cases (45.0%) in which the tumors secreted more than two kinds of hormones, 7 cases in insulinoma, 2 cases in nonfunctioning tumors. Whether the tumor secreted multiple hormones was detected by the method of immunohistochemical staining. Though the tumors secreted more than two kinds of hormones, the patients with the tumors complained of symptoms which were associated with the cell type most strongly stained by immunohistochemical method. Whether or not the tumors secreted multiple hormones was not associated with the pathologic features such as tumor size, histologic patterns of the tumor, status of tumor cell differentiation and malignancy. CONCLUSION: From this results, we suggest that endocrine tumors of the pancreas secreted multiple hormones not by the mechanism of dedifferentiation from already differentiated endocrine cells but by the mechanism of neogenesis of multipotent islet stem cells. Since the relationship between the function of multiple hormone secretion in the endocrine pancreas tumors and islet stem cell would be significant, further study should be needed to find out the function of stem cells and application of stem cells to clinical use.
Cell Differentiation ; Endocrine Cells ; Humans ; Incidence ; Insulinoma ; Islets of Langerhans ; Pancreas* ; Rare Diseases ; Retrospective Studies ; Seoul ; Somatostatinoma ; Stem Cells

There is an increasing interest in the epidemiology of children's fractures particullary to the patterns of children's fractures but there is a few available articles about them. We reviewed 398 children under the 15 years of age who were affected by fractures during 4 years and analysed the patterns of children's fractures concerning with the sex, age, seasons of a year, etiology, fracture sites and the types of fractures. The results were as follows : 1. Boys were affected about 2.5 times than girls. Fractures were predominant in between 5 and 9 years of age group. 2. The three highest monthly incidences of the fractures were showed in July, September and October. 3. The major causes of fractures were fall from a height or slipdown, pedestrian traffic accidents and sports injury in decreasing orders. 4. The traffic accidents were occured frequently in children of five to seven year old, and it is occured predominantly in June, July and August(37.8%). 5. The frequent sites of children's fractures were humerus(33.5%), tibia(21.0%), forearm (17.3%) and femur(13.6%). 6. The sports injuries were affected evenly in all age groups except below 3 years old children and the frequent causes were bicycling, exercising on the horizontal bar, Korean wrestling and during football game in decreasing orders.
Accidents, Traffic ; Athletic Injuries ; Bicycling ; Child ; Clinical Study ; Epidemiology ; Female ; Football ; Forearm ; Humans ; Incidence ; Seasons ; Wrestling

Arrhythmogenic right ventricular dysplasia is a rare heart muscle disorder of unknown cause that primarily involves the right ventricle. It is characterized pathologically by fibrofatty replacement of the right ventricular myocardium. Clinical manifestations include structural and functional abnormalities of the right ventricle, electrocardiographic depolarization/repolarization changes, and presentation with sudden death or ventricular arrhythmias of right ventricular origin. It is one of the important causes of the ventricular arrhythmia or sudden death among apparently healthy young people. We report a case of arrhythmogenic right ventricular dysplasia with the review of the literature.
Arrhythmias, Cardiac ; Arrhythmogenic Right Ventricular Dysplasia* ; Death, Sudden ; Electrocardiography ; Heart Ventricles ; Myocardium

BACKGROUND: Multidrug-resistant (MDR) Acinetobacter spp. acquire antimicrobial agent-resistance genes via class 1 integrons. In this study, integrons were characterized to investigate the antimicrobial resistance mechanisms of MDR Acinetobacter isolates. In addition, the relationship between the integron type and integron-harboring bacterial species was analyzed by using epidemiological typing methods. METHODS: Fifty-six MDR Acinetobacter spp.-A. baumannii (N=30), A. bereziniae (N=4), A. nosocomialis (N=5), and A. pittii (N=17)-were isolated. The minimum inhibitory concentrations (MICs) were determined on the basis of the results of the Epsilometer test (Etest). PCR and DNA sequencing was performed to characterize the gene cassette arrays of class 1 integrons. Multilocus sequence typing (MLST) and repetitive extragenic palindromic sequence (REP)-PCR were performed for epidemiological typing. RESULTS: Class 1 integrons were detected in 50 (89.3%) of the 56 isolates, but no class 2 or 3 integron was found within the cohorts. The class 1 integrons were classified into 4 types: 2.3-kb type A (aacA4-catB8-aadA1), 3.0-kb type B (aacA4-blaI(MP-1)-bla(OXA-2)), 3.0-kb type C (bla(VIM-2)-aacA7-aadA1), and 1.8-kb type D (aac3-1-bla(OXA-2)-orfD). Type A was most prevalent and was detected only in A. baumannii isolates, except for one A. bereziniae isolate; however, type B was amplified in all Acinetobacter isolates except for A. baumannii isolates, regardless of clone and separation time of the bacteria. CONCLUSIONS: Although class 1 integron can be transferred horizontally between unrelated isolates belonging to different species, certain types of class 1 integrons tend to transfer horizontally and vertically among A. baumannii or non-baumannii Acinetobacter isolates.
Acinetobacter/drug effects/isolation & purification/*metabolism ; Acinetobacter Infections/epidemiology/microbiology ; Acinetobacter baumannii/drug effects/isolation & purification/metabolism ; Anti-Bacterial Agents/pharmacology ; DNA, Bacterial/chemistry/metabolism ; Drug Resistance, Multiple, Bacterial ; Humans ; Integrons/*genetics ; Microbial Sensitivity Tests ; Multilocus Sequence Typing ; Polymerase Chain Reaction ; Republic of Korea

BACKGROUND: Pseudomonas aeruginosa is a clinically important pathogen that causes opportunistic infections and nosocomial outbreaks. Recently, the type III secretion system (TTSS) has been shown to play an important role in the virulence of P. aeruginosa. ExoU, in particular, has the greatest impact on disease severity. We examined the relationship among the TTSS effector genotype (exoS and exoU), fluoroquinolone resistance, and target site mutations in 66 carbapenem-resistant P. aeruginosa strains. METHODS: Sixty-six carbapenem-resistant P. aeruginosa strains were collected from patients in a university hospital in Daejeon, Korea, from January 2008 to May 2012. Minimum inhibitory concentrations (MICs) of fluoroquinolones (ciprofloxacin and levofloxacin) were determined by using the agar dilution method. We used PCR and sequencing to determine the TTSS effector genotype and quinolone resistance-determining regions (QRDRs) of the respective target genes gyrA, gyrB, parC, and parE. RESULTS: A higher proportion of exoU+ strains were fluoroquinolone-resistant than exoS+ strains (93.2%, 41/44 vs. 45.0%, 9/20; P< or =0.0001). Additionally, exoU+ strains were more likely to carry combined mutations than exoS+ strains (97.6%, 40/41 vs. 70%, 7/10; P=0.021), and MIC increased as the number of active mutations increased. CONCLUSIONS: The recent overuse of fluoroquinolone has led to both increased resistance and enhanced virulence of carbapenem-resistant P. aeruginosa. These data indicate a specific relationship among exoU genotype, fluoroquinolone resistance, and resistance-conferring mutations.
ADP Ribose Transferases/genetics ; Anti-Bacterial Agents/*pharmacology ; Bacterial Proteins/genetics ; Bacterial Toxins/genetics ; Carbapenems/pharmacology ; Drug Resistance, Bacterial/*drug effects ; Fluoroquinolones/*pharmacology ; Genotype ; Humans ; Microbial Sensitivity Tests ; Multilocus Sequence Typing ; Mutation ; Pseudomonas aeruginosa/*genetics/isolation & purification/pathogenicity ; Sputum/microbiology ; Virulence

BACKGROUND: Hepcidin plays a central role in the regulation of iron metabolism, and hepatic iron production is stimulated by iron load and inflammation. Recent animal studies have shown that hepcidin levels increase when hematopoiesis is blocked. We aimed to monitor pre- and post-stem cell transplantation hepcidin levels and evaluate its association with hematologic recovery. METHODS: The study group comprised 12 patients with hematologic malignancies (7 with AML, 4 with ALL, and 1 with refractory anemia with excess blasts-2) undergoing allogeneic peripheral blood stem cell transplantation (PBSCT). One day before and 3 days, 1 week, 2 weeks, 4 weeks, and 8 weeks after PBSCT, reticulocyte count and levels of Hb, ferritin, and C-reactive protein were monitored; serum hepcidin-25 was measured by ELISA. RESULTS: The median serum hepcidin-25 levels (ng/mL) were significantly higher until 1 week after PBSCT (103.6, 103.3, and 96.5) than those at 2, 4, and 8 weeks after PBSCT (63.9, 53.9, and 56.6, respectively). The reticulocyte count also significantly increased from 2 weeks after PBSCT. The hepcidin level showed an inverse correlation with reticulocyte count (r=-0.56, P<0.001) and a weak positive correlation with ferritin (r=0.27, P=0.02). At 2 weeks, patients with high hepcidin levels (> or =63.9) tended to demonstrate lower Hb recovery at 8 weeks than patients with low hepcidin levels did (P=0.15), but without any differences in the incidence of complications. CONCLUSIONS: These findings indicate that hepcidin production is associated with erythropoietic activity and that hepcidin level may be used as an early marker of hematopoietic recovery in PBSCT.
Anemia, Refractory ; Animals ; Antimicrobial Cationic Peptides ; C-Reactive Protein ; Cell Transplantation ; Ferritins ; Hematologic Neoplasms ; Hematopoiesis ; Humans ; Incidence ; Inflammation ; Iron ; Organothiophosphorus Compounds ; Peripheral Blood Stem Cell Transplantation ; Reticulocyte Count ; Stem Cell Transplantation ; Transplants

BACKGROUND: From January 2014 to December 2015, 69 clones of Enterobacter cloacae showing multidrug resistance to six classes of antimicrobial agents were collected from two medical centers in Korea. METHODS: Minimum inhibitory concentrations were determined using the E-test method, and 17 genes were detected using polymerase chain reaction (PCR). The epidemiological relatedness of the strains was identified using repetitive element sequence-based PCR and multilocus sequence typing. RESULTS: The 69 E. cloacae clones produced extended spectrum β lactamase (ESBL) and AmpC and showed multidrug resistance to cefotaxime, ceftazidime, and aztreonam. We identified the following sequence types: ST56 of type VI for ESBL SHV (N=12, 17.4%); ST53, ST114, ST113, and ST550 of types I, IV, VI, and VII, respectively, for CTX-M (N=11, 15.9%); and ST668 of type III for the carbapenemase NDM gene (N=1, 1.5%). The AmpC DHA gene (N=2, 2.89%) was confirmed as ST134, although its type was not identified, whereas EBC (MIR/ACT; N=18, 26.1%) was identified as ST53, ST24, ST41, ST114, ST442, ST446, ST484, and ST550 of types V, I, III, IV, VII, and VI, respectively. The formed subclasses were bla CTX-M-3 and bla CTX-M-22 by CTX-M-1, bla CTX-M-9 and bla CTX-M-125 by CTX-M-9, bla DHA-1 by DHA, and bla MIR-7 and bla ACT-15,17,18,25,27,28 by EBC (MIR/ACT). CONCLUSIONS: There were no epidemiological relationships between the gene products and the occurrence of resistance among the strains.
Anti-Infective Agents ; Aztreonam ; Cefotaxime ; Ceftazidime ; Cloaca ; Clone Cells ; Drug Resistance, Multiple* ; Enterobacter cloacae* ; Enterobacter* ; Korea ; Methods ; Microbial Sensitivity Tests ; Multilocus Sequence Typing ; Polymerase Chain Reaction

PURPOSE: Bone morphogenetic proteins (BMPs) are members of the transforming growth factor-beta family and play an important role in cellular growth. Recent reports suggest that exogenous bone morphogenetic protein-2 (BMP-2) acts as an antiproliferative agent in a variety of cell lines. We will study whether BMP-2 is altered in human colorectal cancer. METHODS: We analyzed 40 colorectal cancer cases and 6 colorectal cancer cell lines by using reverse transcription-polymerase chain reaction (RT-PCR) to determine the expression of BMP-2. RESULTS: Thirteen of 40 colorectal cancers (33%) and 3 of 6 colorectal cancer cell lines (50%) revealed decreased expression of BMP-2. The rates of decreased expression were 0% (0/7), 42.1% (8/19), 28.6% (2/7), 33.3% (2/6), and 100% (1/1) in stages I, II, III, and IV, respectively. Histologically, the rates were 33.3% (2/6), 32.2% (10/21), 50% (1/2), and 0% (0/1) in well-differentiated, moderately-differentiated, poorly-differentiated and mucinous cancers, respectively. As for location, the rates for colon and rectal cancers were 27.8% (5/18) and 36.4% (8/22), respectively. We identified methylation in the CpG island of the BMP-2 gene in 60% of colorectal cancer cells and in 50% of colorectal cancer cell lines. The 13 cases without BMP-2 gene expression showed no significant correlation with clinicopathological factors. Epigenetic silencing through DNA methylation is one of the key steps during carcinogenesis. CONCLUSION: We found, through an analysis using the methylation-specific polymerase chain reaction technique, CpG island methylation of the BMP-2 promoter region in colorectal cancer. Thus, aberrant BMP-2 methylation and the resultant loss of BMP-2 expression may be related to colorectal carcinogenesis.
Bone Morphogenetic Proteins ; Cell Line ; Colon ; Colorectal Neoplasms ; CpG Islands ; DNA Methylation ; Epigenomics ; Gene Expression ; Humans ; Methylation ; Mucins ; Polymerase Chain Reaction ; Promoter Regions, Genetic ; Rectal Neoplasms

No abstract available.
Adrenocortical Adenoma* ; Lipomatosis* ; Paraplegia*