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Kwang-Soo Kim

Publications and source records attributed to Kwang-Soo Kim.

62 records · Page 4Linked to original sources

A case of brief psychosis associated with an arachnoid cyst.

Little is known about the arachnoid cyst and there have been few reports of it accompanying psychiatric disturbances. A 57-year-old patient was admitted due to sudden headache, auditory hallucination, and delusion of persecution. An arachnoid cyst was found in the anteromedial aspect of middle cranial fossa on his magnetic resonance image. This was his first psychotic episode and he was also negative to other clinical evaluations including endocrine system. His psychotic symptoms were suspected to be induced by the arachnoid cyst and it was well controlled by low-dose risperidone administration. He left hospital free from psychotic symptoms on 14th hospital day.

Antipsychotic Agents↗

Genetic engineering of mouse embryonic stem cells by Nurr1 enhances differentiation and maturation into dopaminergic neurons.

Nurr1 is a transcription factor critical for the development of midbrain dopaminergic (DA) neurons. This study modified mouse embryonic stem (ES) cells to constitutively express Nurr1 under the elongation factor-1alpha promoter. The Nurr1-expression in ES cells lead to up-regulation of all DA neuronal markers tested, resulting in about a 4- to 5-fold increase in the proportion of DA neurons. In contrast, other neuronal and glial markers were not significantly changed by Nurr1 expression. It was also observed that there was an additional 4-fold increase in the number of DA neurons in Nurr1-expressing clones following treatment with Shh, FGF8 and ascorbic acid. Several lines of evidence suggest that these neurons may represent midbrain DA neuronal phenotypes; firstly, they coexpress midbrain DA markers such as aromatic L-amino acid decarboxylase, calretinin, and dopamine transporter, in addition to tyrosine hydroxylase and secondly, they do not coexpress other neurotransmitters such as GABA or serotonin. Finally, consistent with an increased number of DA neurons, the Nurr1 transduction enhanced the ability of these neurons to produce and release DA in response to membrane depolarization. This study demonstrates an efficient genetic manipulation of ES cells that facilitates differentiation to midbrain DA neurons, and it will serve as a framework of genetic engineering of ES cells by key transcription factor to regulate their cell fate.

Animals↗

Effects of desipramine treatment on norepinephrine transporter gene expression in the cultured SK-N-BE(2)M17 cells and rat brain tissue.

The antidepressant desipramine (DMI) is a selective inhibitor of norepinephrine (NE) transport that down-regulates the norepinephrine transporter (NET) protein in a concentration- and time-dependent manner in vitro. In this study, possible regulatory effects of DMI on NET mRNA and protein levels were investigated with the NET-expressing SK-N-BE(2)M17 cell line and rat brain tissue. Northern blot analysis showed that incubation of the cultured cells with DMI (5-500 nm) for 3 days reduced levels of NET mRNA in both its 5.8-kb (by up to 58%) and 3.6-kb forms (to 68%), whereas incubation for 14 days increased both levels (to 40% and 100%) in a concentration-dependent manner. In contrast, NET protein levels decreased after 3-14 days of exposure of the cells to DMI, as determined by western blotting. The in vitro findings were supported by in vivo treatment of rats with DMI. Thus, in situ hybridization demonstrated initially decreased, and later increased, NET mRNA levels in locus coeruleus (LC) tissue of rats treated with DMI; whereas NET protein levels in the LC were reduced after 14 days, but unchanged after three daily DMI treatments. Thus, DMI had similar effects on NET expression in vitro and in vivo, with opposite changes in NET mRNA and protein levels, suggesting that the regulatory mechanisms involved are complex and non-congruent.

Animals↗

Genetic basis of clinical catecholamine disorders.

Norepinephrine and epinephrine are critical determinants of minute-to-minute regulation of blood pressure. Here we review the characterization of two syndromes associated with a genetic abnormality in the noradrenergic pathway. In 1986, we reported a congenital syndrome of undetectable tissue and circulating levels of norepinephrine and epinephrine, elevated levels of dopamine, and absence of dopamine-beta-hydroxylase (DBH). These patients appeared with ptosis and severe orthostatic hypotension and lacked sympathetic noradrenergic function. In two persons with DBH deficiency, we identified seven novel polymorphisms. Both patients are compound heterozygotes for a variant that affects expression of DBH protein via impairment of splicing. Patient 1 also has a missense mutation in DBH exon 2, and patient 2 carries missense mutations in exons 1 and 6. Orthostatic intolerance is a common syndrome affecting young women, presenting with orthostatic tachycardia and symptoms of cerebral hypoperfusion on standing. We tested the hypothesis that abnormal norepinephrine transporter (NET) function might contribute to its etiology. In our proband, we found an elevated plasma norepinephrine with standing that was disproportionate to the increase in levels of dihydroxphenylglycol, as well as impaired norepinephrine clearance and tyramine resistance. Studies of NET gene structure revealed a coding mutation converting a conserved alanine residue in transmembrane domain 9 to proline. Analysis of the protein produced by the mutant cDNA demonstrated greater than 98% reduction in activity relative to normal. The finding of genetic mutations responsible for DBH deficiency and orthostatic intolerance leads us to believe that genetic causes of other autonomic disorders will be found, enabling us to design more effective therapeutic interventions.

Catecholamines↗

Analysis of different promoter systems for efficient transgene expression in mouse embryonic stem cell lines.

Mouse embryonic stem (ES) cells are derived from the inner cell mass of the preimplantation embryo and have the developmental capacity to generate all cell types of the body. Combined with efficient genetic manipulation and in vitro differentiation procedures, ES cells are a useful system for the molecular analysis of developmental pathways. We analyzed and compared the transcriptional activities of a cellular polypeptide chain elongation factor 1 alpha (EF), a cellular-virus hybrid (cytomegalo-virus [CMV] immediate early enhancer fused to chicken beta-actin [CBA]), and a viral CMV promoter system in two ES cell lines. When transiently transfected, the EF and CBA promoters robustly drove reporter gene expression, while the CMV promoter was inactive. We also demonstrated that the EF and CBA promoters effectively drove gene expression in different stages of cell development: naïve ES cells, embryoid bodies (EBs), and neuronal precursor cells. In contrast, the CMV promoter did not have transcriptional activity in either ES cells or EB but had significant activity once ES cells differentiated into neuronal precursors. Our data show that individual promoters have different abilities to express reporter gene expression in the ES and other cell types tested.

Actins↗

Effects of olanzapine on prolactin levels of female patients with schizophrenia treated with risperidone.

BACKGROUND: This study was conducted to prospectively examine the effect of switching from risperidone to olanzapine on female schizophrenia patients who experienced menstrual disturbances, galactorrhea, and/or sexual dysfunction. METHOD: Twenty female patients with DSM-IV schizophrenia who were taking risperidone and were suffering from menstrual disturbances, galactorrhea, and/or sexual dysfunction were enrolled. Patients were switched from risperidone to olanzapine over a 2-week period, then treated with olanzapine for 8 additional weeks. The serum prolactin concentrations were examined every 2 weeks. The Positive and Negative Syndrome Scale (PANSS), Abnormal Involuntary Movement Scale (AIMS), Simpson-Angus Scale for Extrapyramidal Symptoms (SAS), and questions from the Dickson-Glazer Sexual Functioning Scale were administered to evaluate efficacy, extrapyramidal side effects, and sexual and reproductive functioning at baseline and the endpoint of 10 weeks. RESULTS: Serum prolactin levels decreased significantly (p < .01) following the switch from risperidone to olanzapine. Scores of PANSS, AIMS, and SAS at the endpoint were also significantly decreased (p < .01) compared to those of baseline. Patients experienced improvements in menstrual functioning and perceptions of sexual side effects. CONCLUSION: Olanzapine reversed hyperprolactinemia in risperidone-treated female schizophrenic patients. This was associated with a decrease in amenorrhea, improved cycle regularity, and a decrease in sexual side effects that the women attributed to antipsychotic medication. This study suggests that switching to olanzapine is a safe and effective alternative method for patients with antipsychotic-induced hyperprolactinemia associated sexual and/or reproductive dysfunction. Long-term follow-up studies are warranted, with particular attention to the course of sexual and reproductive dysfunction.

Adolescent↗