BACKGROUND: This study was designed to provide logical backgrounds for the revision of biological exposure indices (BEIs) for styrene exposure in Korea. In order to investigate the correlation between airborne styrene and biological exposure indices, we measured urinary mandelic acid (MA) and phenylglyoxylic acid (PGA) in workers exposed to styrene occupationally, as well as airborne styrene at workplaces. METHODS: Surveys were conducted for 56 subjects. The concentrations of airborne styrene and urinary metabolites of styrene were measured in 36 workers who were occupationally exposed to styrene, and in 20 controls. Air samples were collected using personal air samplers and analyzed by gas chromatography. Urine samples were collected at the end of the shift and analyzed by high performance liquid chromatography. RESULTS: The geometric mean concentration of airborne styrene was 9.6 ppm. The concentrations of urinary MA, PGA, and MA+PGA in the exposure group were 267.7, 143.3, and 416.8 mg/g creatinine, respectively. The correlation coefficients for correlation between airborne styrene and MA, PGA, and MA+PGA were 0.714, 0.604, and 0.769, respectively. The sum of urinary MA and PGA corresponding to an exposure of 20 ppm styrene was 603 mg/g creatinine. CONCLUSION: The correlation of the sum of urinary MA and PGA with airborne styrene was better than the correlation of each individual urinary determinant. It is considered appropriate to amend the concentration of urinary MA+PGA to 600 mg/g creatinine as a BEI, which corresponds to an airborne styrene concentration of 20 ppm in Korea.
Chromatography, Gas ; Chromatography, Liquid ; Creatinine ; Humans ; Korea ; Logic ; Occupations ; Styrene

The authors of the present study report the prenatal detection of a chromosomal abnormality with additional satellites on the distal short arm of chromosome 8. A 35-year-old woman was referred for amniocentesis because of her advanced maternal age and positive result for maternal serum screening test. Cytogenetic analysis of cultured amniocytes showed a satellite 8p chromosome. The satellite 8p chromosome was positive for nucleolus organizer region (NOR) staining. The parents' karyotypes were normal. Fluorescence in situ hybridization (FISH) study for metaphases of fetal amniocytes revealed a cryptic translocation of chromosomes 8p and 22p. The fetal karyotype was described as 46,XY,8ps.ish t(8;22)(p23.3;p11.2) (D8S504-;D8S504+)dn. The parents decided to continue the pregnancy and a phenotypically normal boy was born at 38 weeks of gestation. In case of de novo terminal NORs detected prenatally, more accurate cytogenetic and molecular analysis should be performed in order to rule out cryptic chromosomal rearrangement among other chromosomes.
Adult ; Amniocentesis ; Arm ; Chromosome Aberrations ; Chromosomes, Human, Pair 8 ; Cytogenetic Analysis ; Cytogenetics ; Female ; Fluorescence ; Humans ; In Situ Hybridization ; Karyotype ; Mass Screening ; Maternal Age ; Metaphase ; Nucleolus Organizer Region ; Parents ; Pregnancy ; Prenatal Diagnosis

OBJECTIVES: Treating olfactory dysfunction is a challenge for physicians. One of the therapeutic options could be transplantation of stem cells. In this study, neural stem cells were transplanted into anosmic mice. METHODS: Neural stem cells were generated from the olfactory bulb of green fluorescent protein (GFP)-transgenic C57BL6 mice. Anosmia were induced by injection of intraperitoneal 3-methylindole. The neural stem cells were transplanted transnasally on the next day. The olfactory function was evaluated by a food-finding test once a week. The olfactory neuroepithelium was harvested for histologic examination and protein analysis at 4 weeks. RESULTS: Twenty-five percent (6/24) of the control mice that were not transplanted with neural stem cells survived at 4 weeks while 67% (8/12) of the transplanted mice survived (P=0.029). The food finding test showed that the transplanted mice resumed finding food at 3 weeks while the control mice resumed finding food at 4 weeks. GFP-positive cells were observed in the olfactory neuroepithelium of the transplanted mice. Western blotting revealed that the olfactory marker protein expression was significantly lower in the control mice than that in the transplanted mice. CONCLUSION: This study demonstrated that improvement of mouse survival was achieved and recovery of olfactory function was promoted by transnasal transplantation of neural stem cells in the anosmic mouse model. These results indicate that stem cells might be one of the future modalities for treating olfactory impairment.
Animals ; Blotting, Western ; Mice ; Neural Stem Cells ; Olfaction Disorders ; Olfactory Bulb ; Olfactory Marker Protein ; Skatole ; Smell ; Stem Cells ; Transplants

PURPOSE: This study was designed to confirm whether the paracentric inversions of fetuses and parents may be harmless. MATERIALS AND METHODS: We report 10 cases (0.14%) with paracentric inversions among 7,181 prenatal cases observed during prenatal diagnosis performed at Cheil General Hospital between January 2009 and June 2013. We used cytogenetic GTL- and RBG-banding techniques. RESULTS: Of the 10 cases, nine cases were transmitted from each of the parents, and one case was de novo. Nine cases were phenotypically normal up to one month of age after birth. One case was lost to follow-up. We present prenatal diagnosis and follow-up examination of the fetuses with paracentric inversion. CONCLUSION: Based on our cases, most paracentric inversions are considered to be harmless. The precise identification of paracentric inversions might be clinically important and helpful for genetic counseling.
Amniocentesis ; Chorionic Villi Sampling ; Cytogenetics ; Female ; Fetus ; Follow-Up Studies ; Genetic Counseling ; Hospitals, General ; Humans ; Lost to Follow-Up ; Parents ; Parturition ; Pregnancy ; Prenatal Diagnosis*

Objectives: Although it is difficult to define the quality of stroke care, acute ischemic stroke (AIS) patients with moderate-to-severe neurological deficits may benefit from thrombectomy-capable hospitals (TCHs) that have a stroke unit, stroke specialists, and a substantial endovascular thrombectomy (EVT) case volume. Methods: From national audit data collected between 2013 and 2016, potential EVT candidates arriving within 24 hours with a baseline National Institutes of Health Stroke Scale score ≥6 were identified. Hospitals were classified as TCHs (≥15 EVT case/y, stroke unit, and stroke specialists), primary stroke hospitals (PSHs) without EVT (PSHs-without-EVT, 0 case/y), and PSHs-with-EVT. Thirty-day and 1-year case-fatality rates (CFRs) were analyzed using random intercept multilevel logistic regression. Results: Out of 35 004 AIS patients, 7954 (22.7%) EVT candidates were included in this study. The average 30-day CFR was 16.3% in PSHs-without-EVT, 14.8% in PSHs-with-EVT, and 11.0% in TCHs. The average 1-year CFR was 37.5% in PSHs-without-EVT, 31.3% in PSHs-with-EVT, and 26.2% in TCHs. In TCHs, a significant reduction was not found in the 30-day CFR (odds ratio [OR], 0.92; 95% confidence interval [CI], 0.76 to 1.12), but was found in the 1-year CFR (OR, 0.84; 95% CI, 0.73 to 0.96). Conclusions The 1-year CFR was significantly reduced when EVT candidates were treated at TCHs. TCHs are not defined based solely on the number of EVTs, but also based on the presence of a stroke unit and stroke specialists. This supports the need for TCH certification in Korea and suggests that annual EVT case volume could be used to qualify TCHs.

Prenatal diagnosis of rare autosome mosaicism involvingchromosomes other than chromosome 13, 18, 21 or the sex chromosome is encountered prognostic dilemma during genetic counseling. We report four cases of level III uncommon mosaicism of trisomy 5, 16 and 20,diagnosed prenatally. In case 1 with mosaic trisomy 20, there was a higher mosaic ratio of trisomy 20 in the repeat amniocentesis (62.1%) than in the first (36.6%) with normal fetal ultrasound finding except for a relatively small aorta on a 3-vessel view of the fetal heart. Case 2 showed a low rate of mosaic trisomy 20 (5.25%) in cultured amniocytes but normal karyotype in the repeat amniocentesis, who delivered a normal healthy baby. Case 3 showed a 13.6% of trisomy 16 mosaicism in the 30 cells of cultured amniocytes. Sixty cells from a fetal blood sample at termination showed non-mosaic 46,XX normal karyotype, while skin fibroblasts had 22.5% trisomy 16 in 40 metaphases. The autopsy showed ventricular septal defect (VSD). Case 4 with low grade mosaicism (10.5%) of trisomy 5 resulted in elective termination, though the ultrasoumd showed growsly normal fetus. Although level III mosaicism is regarded as true mosaicism, it is difficult to predict the outcome of the fetus with rare mosaic autosome trisomy. Therefore mosaic autosome trisomy of fetus should be carefully interpreted with more various approaches including repeat sampling and targeted fetal ultrasound.
Amniocentesis ; Aorta ; Autopsy ; Chromosomes, Human, Pair 13 ; Chromosomes, Human, Pair 16 ; Chromosomes, Human, Pair 20 ; Fetal Blood ; Fetal Heart ; Fetus ; Fibroblasts ; Genetic Counseling ; Heart Septal Defects, Ventricular ; Karyotype ; Metaphase ; Mosaicism ; Prenatal Diagnosis ; Sex Chromosomes ; Skin ; Trisomy

We herein report an analysis of a female baby with a de novo dup(10p)/del(10q) chromosomal aberration. A prenatal cytogenetic analysis was performed owing to abnormal ultrasound findings including a choroid plexus cyst, prominent cisterna magna, and a slightly medially displaced stomach. The fetal karyotype showed additional material attached to the terminal region of chromosome 10q. Parental karyotypes were both normal. At birth, the baby showed hypotonia, upslanting palpebral fissures, a nodular back mass, respiratory distress, neonatal jaundice and a suspicious polycystic kidney. We ascertained that the karyotype of the baby was 46,XX,der(10)(pter-->q26.3::p11.2-->pter) by cytogenetic and molecular cytogenetic analyses including high resolution GTG- and RBG-banding, fluorescence in situ hybridization, comparative genomic hybridization, and short tandem repeat marker analyses. While almost all reported cases of 10p duplication originated from one of the parents with a pericentric inversion, our case is extraordinarily rare as the de novo dup(10p)/del(10q) presumably originated from a rearrangement at the premeiotic stage of the parental germ cell or from parental germline mosaicism.
Choroid Plexus ; Chromosome Aberrations ; Chromosomes, Human, Pair 10 ; Cisterna Magna ; Comparative Genomic Hybridization ; Cytogenetic Analysis ; Cytogenetics ; Female ; Fluorescence ; Germ Cells ; Humans ; In Situ Hybridization ; Infant, Newborn ; Jaundice, Neonatal ; Karyotype ; Korea ; Microsatellite Repeats ; Mosaicism ; Muscle Hypotonia ; Parents ; Parturition ; Polycystic Kidney Diseases ; Stomach ; Ultrasonography

A 35-year-old man with infertility was referred for chromosomal analysis. In routine cytogenetic analysis, the patient was seen to have additional material of unknown origin on the terminal region of the short arm of chromosome 4. To determine the origin of the unknown material, we carried out high-resolution banding, comparative genomic hybridization (CGH), and FISH. CGH showed a gain of signal on the region of 4q32-->q35. FISH using whole chromosome painting and subtelomeric region probes for chromosome 4 confirmed the aberrant chromosome as an intrachromosomal insertion duplication of 4q32-->q35. Duplication often leads to some phenotypic abnormalities; however, our patient showed an almost normal phenotype except for congenital dysfunction in spermatogenesis.
Adult ; Arm ; Chromosome Painting ; Chromosomes, Human, Pair 4 ; Comparative Genomic Hybridization ; Cytogenetic Analysis ; Humans ; In Situ Hybridization, Fluorescence ; Infertility ; Phenotype ; Spermatogenesis ; Trisomy

The 22q11.2 duplication syndrome is an extremely variable disorder with a phenotype ranging from normal to congenital defects and learning disabilities. Recently, the detection rate of 22q11.2 duplication has been increased by molecular techniques, such as array CGH. In this study, we report a familial case of 22q11.2 duplication detected prenatally. Her first pregnancy was terminated because of 22q11.2 duplication detected incidentally by BAC array CGH. The case was referred due to second pregnancy with same 22q11.2 duplication. We perfomed repeat amniocentesis for karyotype and FISH analysis. Karyotype analysis from amniocytes and parental lymphocytes were normal, while FISH analysis of interphase cells presented a duplication of 22q11.2 in the fetus and phenotypically normal mother. The fetal ultrasound showed grossly normal finding. After genetic counseling about variable phenotype with intrafamilial variability with 50% recurrence rate, the couple decided to continue the pregnancy. The newborn had no apparent congenital abnormalities until 2 weeks after birth. We recommend that family members of patients with a 22q11.2 duplication be tested by the interphase FISH analysis. Also, we point out the importance of genetic counseling and an evaluation of the clinical relevance of diagnostic test results.
Amniocentesis ; Congenital Abnormalities ; Diagnostic Tests, Routine ; Fetus ; Genetic Counseling ; Humans ; Infant, Newborn ; Interphase ; Karyotype ; Learning Disorders ; Lymphocytes ; Mothers ; Parents ; Phenotype ; Pregnancy ; Prenatal Diagnosis ; Recurrence

Structural abnormalities of the Y chromosome affect normal testicular differentiation and spermatogenesis. The present case showed a rare monocentric derivative Y chromosome with partial duplication of Yp including the SRY gene and deletion of Yq12 heterochromatin. The karyotype was 46,X,der(Y) (pter-->q11.23::p11.2-->pter).ish der(Y)(DYZ3+,DYZ1-,SRY++), confirmed through a FISH study. Even though the patient possessed an abnormal Y chromosome, testicular biopsy showed normal testicular volumes in the proband, with gonadal hormonal levels in the normal range but bilateral varicocele and hypospermatogenesis. We speculate that the abnormal Y chromosome arose from sister chromatids during Y chromosome recombination or intra chromosomal NAHR (non-allelic homologous recombination) during meiosis in the patient's father or in the very early stages of embryogenesis. The derivative Y chromosome might interfere in the meiotic stage of spermatogenesis, leading to the developmental arrest of germ cells. The present case illustrates that the infertility phenotype can have various causes. Also, it emphasizes the importance of accurate and various genetic analyses and could aid in male infertility treatment.
Azoospermia ; Biopsy ; Chromatids ; Embryonic Development ; Fathers ; Female ; Genes, sry ; Germ Cells ; Gonads ; Heterochromatin ; Humans ; Infertility ; Infertility, Male ; Karyotype ; Male ; Meiosis ; Oligospermia ; Phenotype ; Pregnancy ; Recombination, Genetic ; Reference Values ; Siblings ; Spermatogenesis ; Varicocele ; Y Chromosome