• Korean Journal of Biological Psychiatry
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• v.7 no.2
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• pp.115-122
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• 2000

The development of molecular biology has brought many changes in psychiatry. Molecular biology makes us possible to know the cause of mental disorders that provide the way to prevent the disorders, and to develop various accurate diagnostic and treatment methods for mental disorders. The author discusses the concept, cause, and treatment of mental disorders in the aspect of molecular biology. Importing the methods of molecular biology into psychiatry, we can anticipate to get a number of the goals of psychiatric genetics, including identification of specific susceptibility genes, clarification of the pathophysiological processes whereby these genes lead to symptoms, establishment of epigenetic factors that interact with these genes to produce disease, validation of nosological boundaries that more closely reflect the actions of these genes, and development of effective preventive and therapeutic interventions based on genetic counseling, gene therapy, and modification of permissive or protective environmental influences. In addition to their capacity to accelerate the discovery of new molecules participating in the nervous system's response to disease or to self-administered drugs, molecular biological strategies can also be used to determine how critical a particular gene product may be in mediating a cellular event with behavioral importance. Molecular biology probably enables us discover the environmental factors of mental disorders and allow rational drug design and gene therapies for mental disorders, by isolation of gene products that facilitate a basic understanding of the pathogenesis of these disorders. A specific genetic linkage may suggest a novel class of drugs that has not yet been tried. With respect to gene therapy, the hypothetical method would use a gene delivery system, most likely a modified virus, to insert a functional copy of a mutant gene into those brain cells that require the gene for normal function.

• Investigative Magnetic Resonance Imaging
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• v.15 no.2
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• pp.91-101
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• 2011

Perfusion magnetic resonance imaging (pMRI) is a special technique for evaluation of blood flow. Exogenous pMRI methods which are dynamic susceptibility contrast (DSC) and dynamic contrast-enhanced (DCE) use an intravenous bolus injection of paramagnetic contrast agent. In contrast, an endogenous pMRM method which is arterial spin labeling (ASL) use diffusible blood in body. In order to scan pMRI in human, technical optimizations are very important according to disease conditions. For examples, DSC is popularly used in patients with acute stroke due to its short scan time, while DSC or DCE provides the various perfusion indices for patients with tumor. ASL is useful for children, women who are expected to be pregnant, and in patients with kidney diseases which are problematic in nephrogenic systemic fibrosis (NSF). Perfusion MRI does not require any injection of radioisotopes. We expect that demand for perfusion MRI will be higher in evaluating drug efficacy and other treatment effects.

• Pediatric Infection and Vaccine
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• v.18 no.1
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• pp.1-14
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• 2011

Tuberculosis is a disease with high morbidity and mortality in children worldwide. Despite the decrease in the incidence of tuberculosis in Korea, more than 30,000 new patients are diagnosed each year. Active tuberculosis is less frequent in children compared to adults but the risk of miliary tuberculosis and CNS tuberculosis is much higher. The diagnosis of tuberculosis in children and adolescents is difficult due to the nonspecific symptoms upon presentation. Diagnostic work up is based on the confirmation of tuberculosis infection by tuberculin skin test, abnormal radiologic findings, and contact with an adult with active tuberculosis. Anti-tuberculosis medications are prescribed according to the drug susceptibility of the index patient. Latent tuberculosis infection plays an important role in adult tuberculosis by reactivation. Thus, it is critical to accurately diagnose latent tuberculosis in children to prevent reactivation in adulthood. Korean guidelines for diagnosis and treatment of tuberculosis in children and adolescents provide evidence based recommendations in the optimal diagnosis and treatment for active and latent tuberculosis in children and adolescents based on the current Korean situation.

• Journal of Microbiology and Biotechnology
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• v.30 no.7
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• pp.974-981
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• 2020

Sequence type 410 (ST410) of Escherichia coli is an extraintestinal pathogen associated with multi drug resistance. In this study, we aimed to investigate the horizontal propagation pathway of a high-risk clone of E. coli ST410 that produces Klebsiella pneumoniae carbapenemase (KPC). blaKPC-encoding E. coli and K. pneumoniae isolates were evaluated, and complete sequencing and comparative analysis of blaKPC-encoding plasmids from E. coli and K. pneumoniae, antimicrobial susceptibility tests, polymerase chain reaction, multilocus sequence typing, and conjugal transfer of plasmids were performed. Whole-genome sequencing was performed for plasmids mediating KPC-2 production in E. coli and K. pneumoniae clinical isolates. Strains E. coli CPEc171209 and K. pneumoniae CPKp171210 were identified as ST410 and ST307, respectively. CPEc171209 harbored five plasmids belonging to serotype O8:H21, which is in the antimicrobial-resistant clade C4/H24. The CPKp171210 isolate harbored three plasmids. Both strains harbored various additional antimicrobial resistance genes. The IncX3 plasmid pECBHS_9_5 harbored blaKPC-2 within a truncated Tn4401a transposon, which also contains blaSHV-182 with duplicated conjugative elements. This plasmid displayed 100% identity with the IncX3 plasmid pKPBHS_10_3 from the K. pneumoniae CPKp171210 ST307 strain. The genes responsible for the conjugal transfer of the IncX3 plasmid included tra/trb clusters and pil genes coding the type IV pilus. ST410 can be transmitted between patients, posing an elevated risk in clinical settings. The emergence of a KPC-producing E. coli strain (ST410) is concerning because the blaKPC-2-bearing plasmids may carry treatment resistance across species barriers. Transgenic translocation occurs among carbapenem-resistant bacteria, which may spread rapidly via horizontal migration.

• Clinical and Experimental Pediatrics
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• v.60 no.5
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• pp.151-157
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• 2017

Purpose: Macrolide resistance rate of Mycoplasma pneumoniae has rapidly increased in children. Studies on the clinical features between macrolide susceptible-M. pneumoniae (MSMP) and macrolide resistant-M. pneumoniae (MRMP) are lacking. The aim of this study was to identify the macrolide resistance rate of M. pneumoniae in Korean children with M. pneumoniae penupmonia in 2015 and compare manifestations between MSMP and MRMP. Methods: Among 122 children (0-18 years old) diagnosed with M. pneumoniae pneumonia, 95 children with the results of macrolide sensitivity test were included in this study. Clinical manifestations were acquired using retrospective medical records. Results: The macrolide resistant rate of M. pneumoniae was 87.2% (82 of 94 patients) in children with M. pneumoniae pneumonia. One patient showed a mixed type of wild type and A2063G mutation in 23S rRNA of M. pneumoniae. There were no significant differences in clinical, laboratory, and radiologic findings between the MSMP and MRMP groups at the first visit to our hospital. The time interval between initiation of macrolide and defervescence was significantly longer in the MRMP group ($4.9{\pm}3.3$ vs. $2.8{\pm}3.1days$, P=0.039). Conclusion: The macrolide resistant rate of M. pneumoniae is very high in children with M. pneumoniae pneumonia in Korea. The clinical manifestations of MRMP are similar to MSMP except for the defervescence period after administration of macrolide. Continuous monitoring of the occurrence and antimicrobial susceptibility of MRMP is required to control its spread and establish strategies for treating second-line antibiotic resistant M. pneumoniae infection.

• Tuberculosis and Respiratory Diseases
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• v.78 no.3
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• pp.253-257
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• 2015

Background: Tuberculosis (TB) is the leading cause of mortality among human immunodeficiency virus (HIV) patients and the majority of them occur in developing countries. The aims of the present study were to determine the frequency of HIV/TB co-infection and other probable associated factors. Methods: This 10 year retrospective study was conducted on 824 HIV patients in the south-west of Iran. HIV infection was diagnosed by the enzyme linked immunosorbent assay and confirmed by Western blot. TB diagnosis was based on consistency of the clinical manifestations, chest X-ray, and microscopic examination. Drug susceptibility testing was done by the proportional method on $L{\ddot{o}}wenstein$-Jensen media. Results: Of 824 HIV patients, 59 (7.2%) were identified as TB co-infected and the majority (86.4%) of them were male. Of the overall TB infected patients, 6 cases (10.2%) showed multidrug-resistant with the mean CD4+ lymphocyte count of $163{\pm}166cells/mm^3$. The main clinical forms of TB were pulmonary (73%). There was a significant (p<0.05) correlation between TB infection and CD4+ lymphocyte counts ${\leq}200cells/mm^3$, gender, prison history, addiction history, and highly active anti-retroviral therapy. Conclusion: We reported novel information on frequency of HIV/TB co-infection and multidrug resistant-TB outcome among co-infected patients that could facilitate better management of such infections on a global scale.

• Journal of Genetic Medicine
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• v.5 no.2
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• pp.89-93
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• 2008

"Personalized medicine," the goal of which is to provide better clinical care by applying patient's own genomic information to their health care is a global challenge for the $21^{st}$ century "genomic era." This is especially true in Korea, where provisions for clinical genetic services are inadequate for the existing demand, let alone future demands. Genomics-based knowledge and tools make it possible to approach each patient as a unique biological individual, which has led to a paradigm-shift in medical practice, giving it more of a predictive focus as compared with current treatment oriented approach. With recent advancements in genomics, many genetic tests, such as susceptibility genetic tests, have been developed for both rare single gene diseases and more common multifactorial diseases. Indeed, genetic tests for presymtomatic individuals and genetic tests for drug response have become widely available, and personalized medicine will face the challenge of assisting patients who use such tests to make appropriate and wise use of genetic risk assessment. A major challenge of genomic medicine lies in understanding and communicating disease risk in order to facilitate and support patients and their families in making informed decisions. Establishment of a health care system with provisions for genetic counseling as an integral part of health care service, in addition to genomic literacy of health care providers, is vital to meet this growing challenge. Realization of the promise of personalized medicine in the era of genomics for improvement of health care is dependent on further development of next generation sequencing technology and affordable sequencing test costs. Also necessary will be policy development concerning the ethical, legal and social issues of genomic medicine and an educated and ready medical community with clinical practice guidelines for genetic counseling and genetic testing.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.2
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• pp.494-498
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• 2009

The emergence and spread of drug-resistant malaria parasites is a serious public health problem in the tropical world. Useful antimalarial drugs such as chloroquine have resistance in the world now. Moreover, other antimalarialdrugs such as mefloquine, halofantrine, atovaquone, proguanil, artemether and lumefantrine retain efficacy but have limitations, one of which is their high cost. New antimalarial drugs are clearly needed now. Cytotoxicity assay and susceptibility assay were performed for the selectivity of herb extracts in vitro. On the basis of high selectivity, 4-day suppressive test and survival test were progressed in Plasmodium berghei-infected mice. The selectivity of Areca catechu L. (ACL) and butanol extract of ACL (ACL-BuOH extract) were 3.4 and 3.0 in vitro, respectively. Moreover in vivo, 4-day suppressive test showed 39.1 % inhibition effect after treated with 150 mg/kg/day ACL-BuOH to P. berghei-infected mice. Survival test also showed 60% survival rate with ACL-BuOH-treated group while all other group mice died. In this study, ACL and ACL-BuOH were investigated for antimalarial activity in vitro and in vivo and they showed a potent antimalarial activity. In particular,ACL-BuOH could specifically lead higher survival rate of mice in vivo. Therefore ACL-BuOH would be a candidate of antimalarial drugs.

• Archives of Pharmacal Research
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• v.25 no.3
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• pp.375-380
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• 2002

Cytochrome P4501A2 (CYP1A2) is a member of the cytochrome P450 family of isozymes involved in the phase I drug metabolism of vertebrates. CYP1A2 is responsible for the activation of a number of aromatic amines to mutagenic and carcinogenic forms. Thus, the level of CYP1A2, which varies among different populations, may determine an individual's susceptibility to these chemicals. We have previously reported on the importance of a cis element named PRB (protected region B) in the regulation of human Cytochrome P4501A2 (CYP1A2) gene, which appeared to act as a positive regulatory element. Closer examination of the PRB sequence (-2218 to -2187 bp) revealed a putative AP-1 binding site, TGACTAA, at -2212 bp (Chung and Bresnick, 1997). To elucidate the role of AP-1 in CYP1A2 regulation, we transiently overexpressed c-Jun and c-Fos transcription factors in human hepatoma HepG2 cells, and examined their influence on the CYP1A2 promoter activity by reporter gene assays. Cotransfection of the c-Jun and the c-Fos expression vectors increased the induced transactivation by five to six fold from the CYP1A2 promoter constructs. However, deletion of the PRB element did not affect the degree of activation by the c-Jun and the c-Fos. Therefore, it is unlikely that the c-Jun and the c-Fos activate the CYP1A2 promoter through this AP-1 consensus-like sequence in the PRB region.

• Molecules and Cells
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• v.39 no.2
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• pp.129-135
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• 2016

Eukaryotic translation initiation factor 2 alpha ($eIF2{\alpha}$), which is a component of the eukaryotic translation initiation complex, functions in cell death and survival under various stress conditions. In this study, we investigated the roles of $eIF2{\alpha}$ phosphorylation in cell death using the breast cancer cell lines MCF-7 and MCF-7/ADR. MCF-7/ADR cells are MCF-7-driven cells that have acquired resistance to doxorubicin (ADR). Treatment of doxorubicin reduced the viability and induced apoptosis in both cell lines, although susceptibility to the drug was very different. Treatment with doxorubicin induced phosphorylation of $eIF2{\alpha}$ in MCF-7 cells but not in MCF-7/ADR cells. Basal expression levels of Growth Arrest and DNA Damage 34 (GADD34), a regulator of $eIF2{\alpha}$, were higher in MCF-7/ADR cells compared to MCF-7 cells. Indeed, treatment with salubrinal, an inhibitor of GADD34, resulted in the upregulation of $eIF2{\alpha}$ phosphorylation and enhanced doxorubicin-mediated apoptosis in MCF-7/ADR cells. However, MCF-7 cells did not show such synergic effects. These results suggest that dephosphorylation of $eIF2{\alpha}$ by GADD34 plays an important role in doxorubicin resistance in MCF-7/ADR cells.