• Clinical and Experimental Pediatrics
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• v.48 no.12
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• pp.1317-1323
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• 2005

Purpose : This study was performed to evaluate the recent frequency of karyotypes in different sex chromosome abnormalities and to evaluate the age and clinical manifestations at diagnosis. Methods : Peripheral blood leukocytes were obtained from subjects who were clinically suspected to have sex chromosome abnormalities and referred to the cytogenetic laboratory in the Department of Pediatrics, Kyungpook National University Hospital from February 1981 to August 2001. Results : The relative frequencies of different sex chromosome abnormalities were Klinefelter(52 percent), Turner(42 percent), XXX syndrome(3 percent) and mixed gonadal dysgenesis(3 percent). The populations of different karyotypes in Klinefelter syndrome were 47,XXY(97 percent) and 46,XY/47,XYY(3 percent). The populations of different karyotypes in Turner syndrome were 45,X(67 percent,), mosaicism(23 percent), and structural aberrations(10 percent). The populations of different karyotypes in XXX syndrome were 47,XXX(67 percent,) and 46,XX/47,XXX(33 percent). All mixed gonadal dysgenesis were 45,X/46,XY. Eighty one percent of sex chromosome abnormalities was diagnosed after puberty. Patients diagnosed with Klinefelter and Turner syndrome in infancy showed nearly normal phenotypes or had minor congenital malformations. Conclusion : Early diagnoses of sex chromosome abnormalities is required to prevent associated morbidities and to maximize growth and development. We have to pay careful attention in diagnoses of Turner syndrome because of the high proportion of mosaicism and structural aberrations.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.9
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• pp.3907-3909
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• 2014

Background: Cytogenetic abnormalities have important implications in diagnosis and prognosis of acute leukemia and are now considered an important part of the diagnostic workup at presentation. Karyotype, if known at the time of diagnosis, guides physicians to plan appropriate management strategies for their patients. Aim and Objectives: To determine the cytogenetic profile of acute lymphoblastic leukemia (ALL) in Pakistani children in order to have insights regarding behavior of the disease. Materials and Methods: A retrospective analysis of all the cases of ALL (<15years old) diagnosed at Aga Khan University from January 2006 to June 2011 was performed. Cytogenetic analysis was made for all cases using the trypsin-Giemsa banding technique. Karyotypes were interpreted using the International System for Human Cytogenetic Nomenclature (ISCN) criteria. Results: A total of 153 patients were diagnosed as ALL during the study period, of which 127 samples successfully yielded metaphase chromosomes. The male to female ratio was 1.8:1. A normal karyotype was present in 51.2% (n=65) of the cases whereas 48.8% (n=62) had an abnormal karyotype. Most of the abnormal cases showed hyperdiploidy(13.4%) followed by t(9;22)(q34;q11.2) (7.08%). Conclusions: This study revealed a relative lack of good prognostic cytogenetic aberrations in Pakistani children with ALL.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.4
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• pp.449-454
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• 1996

Cytogenetic effects of malathion and parathion, the organophosphorus pesticides were studied on goat lymphocytes in culture. The mitotic indices (% of blast cells + cells at metaphase) of goat lymphocytes showed corresponding decrease with the increase in dose of pesticides. Malathion had significant effect only at $150{\mu}g/ml$ or higher dosages while, parathion caused antimitotic effects even at the lowest dose ($5{\mu}g/ml$) tested. The clastogenic effects of malathion were significant ($p{\leq}0.05$) at $100{\mu}g/ml$. In higher doses, the effects were highly significant ($p{\leq}0.01$). The frequency of metaphase plates with chromosomal abnormalities were highest (22.0%) at $200{\mu}g/ml$. The incidences of chromosomal abnormalities were significant ($p{\leq}0.05$) in parathion treated series even at $5{\mu}g/ml$ dose level. At $10{\mu}g/ml$ or higher dose levels the difference between treatment groups and controls were more pronounced ($p{\leq}0.01$). Various types of chromosomal abnormalities were encountered in goat lymphocytes treated by malathion and parathion. However, the incidence of gaps, breaks, acentric fragments, dicentric chromosomes were higher than other types of structural and numerical abnormalities.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5333-5338
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• 2012

Vitamin B6 functions as a coenzyme in >140 enzymatic reactions involved in the metabolism of amino acids, carbohydrates, neurotransmitters, and lipids. It comprises a group of three related 3-hydroxy-2-methyl-pyrimidine derivatives: pyridoxine (PN), pyridoxal (PL), pyridoxamine (PM) and their phosphorylated derivatives [pyridoxal 5'-phosphate (PLP) and pyridoxamine 5'-phosphate (PMP)], In the folate metabolism pathway, PLP is a cofactor for the mitochondrial and cytoplasmic isozymes of serine hydroxymethyltransferase (SHMT2 and SHMT1), the P-protein of the glycine cleavage system, cystathionine ${\beta}$-synthase (CBS) and ${\gamma}$-cystathionase, and betaine hydroxymethyltransferase (BHMT), all of which contribute to homocysteine metabolism either through folate-mediated one-carbon metabolism or the transsulfuration pathway. Folate cofactors carry and chemically activate single carbons for the synthesis of purines, thymidylate and methionine. So the evidence indicates that vitamin B6 plays an important role in maintenance of the genome, epigenetic stability and homocysteine metabolism. This article focuses on studies of strand breaks, micronuclei, or chromosomal aberrations regarding protective effects of vitamin B6, and probes whether it is folate-mediated one-carbon metabolism or the transsulfuration pathway for vitamin B6 which plays critical roles in prevention of cancer and cardiovascular disease.

• Journal of Genetic Medicine
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• v.16 no.2
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• pp.76-80
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• 2019

About 15% to 20% of all clinically recognized pregnancies result in spontaneous abortion or miscarriage, and chromosomal anomalies can be identified in up to 50% of first trimester miscarriages. Chromosomal microarray analysis (CMA) is currently considered first-tier testing for detecting fetal chromosomal abnormalities and is supported by the absence of cell culture failure or erroneous results due to cell contamination in pregnancy loss. Triploidy is a lethal chromosome number abnormality characterized by an extra haploid set of chromosomes. Triploidy is one of the most common chromosomal aberrations in first trimester spontaneous abortions. Here, we report two cases of triploidy abortion that were not detected using array comparative genomic hybridization-based CMA. The aim of this report was to remind clinicians of the limitations of chromosomal testing and the misdiagnosis that can result from biased test selection.

• Environmental Mutagens and Carcinogens
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• v.22 no.3
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• pp.149-156
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• 2002

The detection of many synthetic chemicals used in industry that may pose a genetic hazard in our environment is of great concern at present. Since these substances are not limited to the original products, and enter the environment, they have become widespread environmental pollutants, thus leading to a variety of chemicals that possibly threaten the public health. In this respect, to regulate and to evaluate the chemical hazard will be important to environment and human health. The clastogenicity of 18 synthetic chemicals was evaluated in Chinese hamster lung fibroblast cells in vitro. 4-Chloro-3,5-dimethyl phenol (CAS No. 88-04-0) induced chromosomal aberrations with significance at the concentration of 15.7 $\mu\textrm{g}$/$m\ell$ both in the presence and absence of metabolic activation system. Phenoxybenzene (CAS No. 101-84-8) which is one of the most cytotoxic chemical among 18 chemicals tested revealed no clastogenicity in the range of 0.11-0.43 $\mu\textrm{g}$/$m\ell$ both in the presence and absence of metabolic activation system. From the results of chromosomal aberration assay with 18 synthetic chemicals in Chinese hamster lung cells in vitro, 4-chloro-3,5-dimethyl phenol (CAS No. 88-04-0) revealed weak positive clastogenic results in this study.

• Genomics & Informatics
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• v.10 no.2
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• pp.69-73
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• 2012

The explosive development of genomics technologies including microarrays and next generation sequencing (NGS) has provided comprehensive maps of cancer genomes, including the expression of mRNAs and microRNAs, DNA copy numbers, sequence variations, and epigenetic changes. These genome-wide profiles of the genetic aberrations could reveal the candidates for diagnostic and/or prognostic biomarkers as well as mechanistic insights into tumor development and progression. Recent efforts to establish the huge cancer genome compendium and integrative omics analyses, so-called "integromics", have extended our understanding on the cancer genome, showing its daunting complexity and heterogeneity. However, the challenges of the structured integration, sharing, and interpretation of the big omics data still remain to be resolved. Here, we review several issues raised in cancer omics data analysis, including NGS, focusing particularly on the study design and analysis strategies. This might be helpful to understand the current trends and strategies of the rapidly evolving cancer genomics research.

• Environmental Mutagens and Carcinogens
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• v.24 no.2
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• pp.79-84
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• 2004

Three synthetic chemicals, benzoyl chloride, 2-propyn-l-ol, and 2-phenoxy ethanol were selected for genotoxicity testing, based on production quantity and available genotoxic data. In our previous report, benzoyl chloride induced chromosomal aberrations in Chinese hamster lung (CHL) fibroblast in vitro with and without metabolic activation, while 2-propyn-l-ol and 2-phenoxy ethanol induced only with metabolic activation. To compare the genotoxicity of chromosome aberration assay, the single cell gel electrophoresis (comet) assay subjected using CHL cells. As a result, statistically significant differences of tail moment values of benzoyl chloride, 2-propyn-1-ol, and 2-phenoxy ethanol were observed compared with control values on almost all concentrations with S9 or without S9 metabolic activation system. This results suggest that genotoxic results of the comet assay and the chromosome aberration assay show correlationship of genotoxicity in the CHL fibroblast. In summary, the positive result of chromosome aberration of benzoyl chloride, 2-propyn-l-ol, and 2-phenoxy ethanol was also induced DNA damages in comet assay with same cell line. Consequently, comet assay will be useful and more accurate tool to detect and to confirm the genotoxicity especially DNA damages in CHL fibroblast.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.6
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• pp.1194-1202
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• 2002

A study on the topology optimization of a multi-spectral camera for space-use is presented. The optimization is carried out under self-weight and polishing pressure loading. A multi-spectral camera for space-use experiences degradation of optical image in the space, which can not be detected on the optical test bench on the earth. An optical surface deformation of a primary mirror, which is a principal component of the camera system, is an important factor affecting the optical performance of the whole camera system. In this study, topology optimization of the primary mirror of the camera is presented. As an objective function, a measure of Strehl ratio is used. Total mass of the primary mirror is given as a constraint to the optimization problem. The sensitivities of the objective function and constraint are calculated by direct differentiation method. Optimization procedure is carried out by an optimality criteria method. For the light-weight primary mirror design, a three dimensional model is treated. As a preliminary example, topology optimization considering a self-weight loading is treated. In the second example, the polishing pressure is also included as a loading in the topology optimization of the mirror. Results of the optimized design topology for the mirror with various mass constraints are presented.

• The Korean Journal of Nuclear Medicine
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• v.23 no.1
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• pp.1-6
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• 1989

The occurrence of thyroid disorders is connected with iodine deficiency, defective synthesis or releasing of thyroid hormone and endemicity. Genetic factors are known as a single gene defects, interaction of multiple genes with environmental factors, as well as chromosomal aberrations. Diofnosis thyroid disorders is enforced by I-131 uptake test, thyroid scanning with I-131 or Tc-99 m and serum radioimmunoassays of T3, T4, free T4 and TSH. They were largely classified as hypothyroidism, hyperthyroidism, simple goiter and normal. The pedigree of 58 families was drawn by propositus, and then the correlation between thyroid disorders and TSH levels was analyzed. The results are as follows: 1) The offsprings and their mothers of 15 families were hypothyroidism, THS level was 5 folds for offsprings and 4 folds for mothers in comparison with control group. 2) 13 families were hyperthyyroidism in siblings but their mothers were normal in thyroid function, TSH level of the siblings was lower than control group. 3) Though the offsprings and their mothers of 10 families were similar to TSH level of control group, they are all simple goiter, familial thyroid disorders, in other thyroid function test. The familial thyroid disorders suggested that these transmitted from mothers to offsprings with X-linked dominant or autosomal dominant inheritance.