Deoxyribonucleic Acid Copy Number Aberrations in Vasospastic Angina Patients Using an Array Comparative Genomic Hybridization

BACKGROUND AND OBJECTIVES: Vasospastic angina (VA) is a specific type of coronary artery disease and develops as a result of coronary artery spasm. Recently, a few studies have revealed that VA caused by coronary artery spasm is related to genetic traits. The objective of this study was to use the recently developed technique of array comparative genomic hybridization (CGH) to screen the genetic aberrations of VA. SUBJECTS AND METHODS: To identify candidate genes that might be causally involved in the pathogenesis of VA, genomic deoxyribonucleic acids were extracted from whole blood of 28 patients with VA who presented at Department of Cardiology at Seoul St. Mary's Hospital, Seoul, Korea. The copy number profiles of these patients was then analyzed using array CGH and reverse transcriptase (RT) quantitative polymerase chain reaction (PCR). RESULTS: Array CGH revealed gains in 31 different regions, with losses in the 4q35.2, 7q22.1, 10q26.3, 15q11.2, 16p13.11, 17p11.2 and 19q13.3 regions (more than 32% aberration in these regions). Several loci were found to be frequently including gains of 5p and 11q (50% of samples). The most common losses were found in 7q (54% of samples). Copy number aberrations in chromosomal regions were detected and corresponding genes were confirmed by RT quantitative PCR. The fold change levels were highest in the CTDP1 (18q23), HDAC10 (22q13.33), KCNQ1 (11p15.5-p15.4), NINJ2 (12p13.33), NOTCH2 (1p12-p11.2), PCSK6 (15q26.3), SDHA (5p15.33), and MUC17 (7q22.1) genes. CONCLUSION: Many candidate chromosomal regions that might be related to the pathogenesis of VA were detected by array CGH and should be systematically investigated to establish the causative and specific genes for VA.

Interleukin-1beta Promoter Polymorphisms in Febrile Seizures and GEFS+ / 대한소아신경학회지

PURPOSE: Studies gave conflicting results as to the association between febrile seizures(FSs) and IL1B promoter polymorphisms. In the present study, to determine whether or not the function-related two single nucleotide base C/T biallelic polymorphisms in the promoter region at positions -31 and -511 of the IL1B gene are associated with susceptibility to FSs, the frequencies of the polymorphisms were investigated in children with FSs and GEFS+, and normal control subjects. METHODS: 72 FSs, 23 GEFS+ and 174 healthy control subjects were selected throughout a collaborative study of Catholic Child Neurology Research Group. IL1B promoter -31 C/T and -511 C/T genotyping was performed by means of PCR-restriction fragment length polymorphism. RESULTS: The distribution of IL1B -31 genotypes and the frequencies of allele in children with FSs and GEFS+, and healthy control subjects were not significantly different. The distributions of IL1B -31 genotypes(CC, CT, TT) are 22.2%, 50%, and 27.8% in children with FSs, 21.7%, 43.5% and 34.8% in children with GEFS+, and 27.6%, 49.3% and 24.1% in healthy control subjects. The distribution of IL1B -511 genotypes and the frequencies of allele in children with FSs and GEFS+, and healthy control subjects were not significantly different. The distributions of IL1B -511 genotypes(CC, CT, TT) are 23.6%, 47.2%, and 29.2% in children with FSs, 26.1%, 39.1% and 34.8% in children with GEFS+, and 27.6%, 49.3% and 24.1% in healthy control subjects. CONCLUSION: Theses data suggest that genomic variations of IL1B promoter might not be one of the susceptibility factors for FSs in the Korean population.

Natural Killer T Cells in Acute and Unmedicated Patients with Major Depressive Disorder / 신경정신의학

OBJECTIVES: To evaluate an association between depression and altered immunity, we examined peripheral T lymphocyte or natural killer (NK) cell measures plasma ACTH and cortisol using the flow cytometry in acute and unmedicated patients with major depressive disorder (MDD). METHODS: Forty-two patients with MDD from the outpatient clinic and forty normal controls from the hospital staff were recruited. We applied Hamilton Rating Scale for Depression (HAM-D) and Hamilton Rating Scale for Anxiety (HAM-A) for depressed subjects. Peripheral T lymphocyte or NK cell measures (CD3, CD4, CD8, or CD56) and plasma hormones (ACTH and cortisol) were obtained from all subjects. RESULTS: There were no statistical differences in CD3, CD4, CD8, or CD56 between the two subjects. The number of CD56 cells negatively correlated with HAM-D scores (r=-0.42, p<0.01), but did not correlate with HAM-A scores in patients with MDD. The number of CD56 cells showed strong negative correlation with CD4/CD8 (r=-0.47, p<0.01) in the control group, but not in the depressed group. Patients with MDD had higher cortisol level than controls within the normal range. CONCLUSION: The trait of immunological imbalance and HPA axis abnormality were shown in patients with MDD. Especially, the severity of depression, but not the anxiety, could be reflected as decreased number of CD56 (NK T) cells in acute and unmedicated state.

Single Nucleotide Polymorphisms of GABRG2 in Febrile Seizures and GEFS+ / 대한소아신경학회지

PURPOSE: Febrile seizures are characterized by a heterogenous phenotype segregating as an autosomal dominant trait with incomplete penetrance. Mutations in GABRG2 gene were identified in two families with generalized epilepsy and febrile seizures plus (GEFS+) and with absence epilepsy and febrile seizures(FSs). The present study assessed the role of GABRG2 gene in FSs and GEFS+ of the Korean population. METHODS: 66 FSs, 20 GEFS+ and 94 healthy control subjects were selected throughout a collaborative study of Catholic Child Neurology Research Group. The SNP211037 of GABRG2 was screened by DHPLC. DNA fragments showing variant chromatograms were subsequently sequenced. Genotypes and allelic frequencies for GABRG2 gene polymorphism in three groups were compared. RESULTS: The number of individuals with the GABRG2(SNP211037)-C/C genotype in patients with FSs was significantly greater compared with that in healthy control subjects and the GABRG2(SNP211037)-C allele frequency in patients with FSs was significantly higher than that in healthy control subjects. The odds ratio for developing FSs in individuals with the GABRG2(SNP211037)-CC genotype was 5.96 compard with individuals with the GABRG2(SNP211037)-T/T genotype. In contrast, the GABRG2 (SNP211037) gene in GEFS+ and control groups was not significantly different. CONCLUSION: Theses data suggest that genomic variations of GABRG2 might be one of the susceptibility factors for FSs in the Korean population.

Increased Reactive Oxygen Species Production by Peripheral Blood Mononuclear Leukocytes, not by Polymorphonuclear Leukocytes, in Atopic Dermatitis / 소아알레르기및호흡기학회지

PURPOSE: Reactive oxygen species (ROS) are known as a potential mediators that sustain chronic inflammation in atopic dermatitis (AD). To determine the role of peripheral blood mononuclear leukocytes (MO) and polymorphonuclear leukocytes (PMN) in prolonged inflammation, ROS generation of those cells in AD was examined. METHODS: Seventeen AD patients and 10 healthy controls were enrolled. MO and PMN were stimulated with the reagents: phobol ester (PMA), adenosine triphosphate (ATP), and chemotactic peptide (f-MLP). ROS levels were measured using chemiluminescence assay. RESULTS: In AD, chemiluminescence response of unstimulated MO was higher than that of normal controls. MO from AD patients produced 1.58-1.80 higher ROS for up to 30 minutes than the controls. When the cells were treated with the reagents (PMA, ATP, f-MLP), all the stimuli enhanced chemiluminescence activity of MO. When MO were treated with PMA, the ratio of ROS produced by MO of patients to that of the controls decreased. When the cells were treated with either ATP or f-MLP, the quantity of ROS generated by MO from the controls was greater than the controls. PMN from both AD patients and the controls generated ROS for 30 min similarly. As treated with the reagents, PMN from AD patients produced a smaller ROS than the controls. CONCLUSION: These results indicate MO but not PMN from AD patients were primed and ready for activation in vivo, and a reduced function of PMN from AD patients was observed. In conclusion, enhanced respiratory burst activity of MO is implicated in the prolonged inflammation of AD.

Single Nucleotide Polymorphisms of SCN1A-exon 9 in GEFS+ / 대한소아신경학회지

PURPOSE: Febrile seizures affect 2-5% of all children younger than 6 years old. A small proportion of children with febrile seizures later develop epilepsy. Muations in the voltage-gated sodium channel subunit gene SCN1A have been associated with febrile seizures(FSs) in autosomal dominant generalized epilepsy with febrile seizures plus (GEFS+) families and severe myoclonic epilepsy of infancy. The present study assessed the role of SCN1A in familial typical FSs. METHODS: 22 GEFS+ and 62 FSs were selected throughout a collaborative study of Catholic Child Neurology Research Group. The exon 9 region of SCN1A was screened by DHPLC. DNA fragments showing variant chromatograms were subsequently sequenced. RESULTS: A total 84 individuals(22 GEFS+ and 62 FSs) was screened for mutations. Among 22 GEFS+ and 62 FSs patients, five and forty nine showed simple FSs, and seventeen and thirteen had complex FSs. 0% and 8.3% were younger than 12 months old, 22.7% and 46.8% were between 12 and 35 months old, 18.2% and 41.9% were between 36 and 83 months old, and 59.1% and 0% were older than 84 months old. The ratios of male to female were 1.75:1 and 1.82:1. Mutational analysis detected no mutation of SCN1A. Mutational analysis detected eleven silent exonic polymorphisms at G1212A in exon 9 and forty two polymorphisms on intron 9, and 23 intron A/As in 73 homozygote samples. There were no significant differences in allelic frequencies(G/G intron A/A or G/G, G/G intron G/A, G/A intron G/A, reported G/A) of G1212A in SCN1A-exon 9 between the patients with GEFS+ and FSs(31.8% vs. 32.3%, 54.5% vs. 54.8%, 9% vs. 6.5%, 4.5% vs. 6.5%). CONCLUSION: Although our study demonstrated that SCN1A is not frequently involved in GEFS+ and FSs, further systemic research would be necessary.

Single Nucleotide Polymorphisms of SCN1A-exon 9 in GEFS+ / 대한소아신경학회지

PURPOSE: Febrile seizures affect 2-5% of all children younger than 6 years old. A small proportion of children with febrile seizures later develop epilepsy. Muations in the voltage-gated sodium channel subunit gene SCN1A have been associated with febrile seizures(FSs) in autosomal dominant generalized epilepsy with febrile seizures plus (GEFS+) families and severe myoclonic epilepsy of infancy. The present study assessed the role of SCN1A in familial typical FSs. METHODS: 22 GEFS+ and 62 FSs were selected throughout a collaborative study of Catholic Child Neurology Research Group. The exon 9 region of SCN1A was screened by DHPLC. DNA fragments showing variant chromatograms were subsequently sequenced. RESULTS: A total 84 individuals(22 GEFS+ and 62 FSs) was screened for mutations. Among 22 GEFS+ and 62 FSs patients, five and forty nine showed simple FSs, and seventeen and thirteen had complex FSs. 0% and 8.3% were younger than 12 months old, 22.7% and 46.8% were between 12 and 35 months old, 18.2% and 41.9% were between 36 and 83 months old, and 59.1% and 0% were older than 84 months old. The ratios of male to female were 1.75:1 and 1.82:1. Mutational analysis detected no mutation of SCN1A. Mutational analysis detected eleven silent exonic polymorphisms at G1212A in exon 9 and forty two polymorphisms on intron 9, and 23 intron A/As in 73 homozygote samples. There were no significant differences in allelic frequencies(G/G intron A/A or G/G, G/G intron G/A, G/A intron G/A, reported G/A) of G1212A in SCN1A-exon 9 between the patients with GEFS+ and FSs(31.8% vs. 32.3%, 54.5% vs. 54.8%, 9% vs. 6.5%, 4.5% vs. 6.5%). CONCLUSION: Although our study demonstrated that SCN1A is not frequently involved in GEFS+ and FSs, further systemic research would be necessary.

Merlin Represses Ras-Induced Cyclin D1 Transcription through the Cyclic AMP-Responsive Element

Mutations in the NF2 tumor suppressor gene cause neurofibromatosis type 2, an autosomal dominant inherited syndrome predisposed to the multiple tumors of the nervous system. Merlin, the NF2 gene product was reported to block Ras-mediated cell transformation and represses Ras-induced expression of cyclin D1. However, the potential mechanism underlying the anti-Ras function of merlin on the cyclin D1 is still unclear. In this study, we investigated whether merlin decreases Ha-ras-induced accumulation of cyclin D1 at the transcriptional level, and demonstrated that merlin suppressed Ras-induced cyclin D1 promoter activity mediated by the cyclic AMP-responsive element (CRE) in SK-N-BE (2) C neuroblastoma cells. Furthermore, we found that merlin attenuated active Ras and forskolin-induced CRE-driven promoter activity. These results suggest that the transcriptional repression of the cyclin D1 expression by merlin may contribute to the inhibition of Ras-induced cell proliferation

ATP and Adenosine Induce Growth Inhibition and Apoptosis in Human Trophoblast-like (TL) Cell Line / 대한산부인과학회잡지

BACKGROUND: Although nucleotides -like Adenosine Triphosphate (ATP) and its derivatives Adenosine, were known to induce growth inhibition and apoptosis in diverse cell lines, little is known about their effects on trophoblast. OBJECTIVE: To elucidate the effects of extracellular ATP and adenosine on trophoblast cell growth and to delineate if apoptosis is involved in this mechanism. MATERIALS AND METHODS: We used TL cell line, derived from human term placenta. The cells were cultured for 24, 48, and 72 hours after being treated with ATP and adenosine, each. Also, cell growth according to different concentrations of ATP and adenosine was evaluated. To test whether apoptosis was induced by each nucleotide, DNA fragmentation and nuclear condensation by Hoechst 33258 stain and P53 protein expression were evaluated. RESULTS: Cell growth was inhibited by ATP and adenosine in time and dose-dependent manner. Furthermore, the growth inhibitory effect of adenosine was stronger than ATP, whereas signs of DNA fragmentation and nuclear condensation were observed in ATP treated cells, but not in adenosine treated ones. CONCLUSION: Our results shows that ATP and adenosine exert inhibitory effect on growth in TL cell line. These findings suggest that pathological production of ATP or its metabolites, adenosine, may lead to a pathologic status such as preeclampsia or intrauterine growth restriction.

Anti-apoptotic role of phospholipase D isozymes in the glutamate-induced cell death

Abstract Phospholipase D (PLD) plays an important role as an effector in a variety of physiological processes that reveal it to be a member of the signal transducing phospholipases. Recently, PLD2 was reported as a necessary intermediate in preventing apoptosis induced by hydrogen peroxide or hypoxia in rat pheochromocytoma (PC12) cells. The data presented here show that both PLD isozymes, PLD1 and PLD2 are also required in attenuating glutamate-induced cell death in PC12 cells. Treatment of PC12 cells with glutamate resulted in induction of apoptosis in these cells, which is accompanied by decreased PLD activity and increased ceramide concentration. Incubation of PC12 cells with exogenous C6-ceramide showed a time-dependent decrease of PLD activity. When cDNAs of PLD1 and PLD2 were transfected into PC12 cells respectively, overexpression of PLD1 or PLD2 resulted in inhibition of glutamate-induced apoptotic cell death. These data indicate that both PLD1 and PLD2 play a protective role against glutamate-induced cell death in PC12 cells.

Expression of Genetic Polymorphism of Interleukin-10 (IL-10) and Tumor Necrosis Factor-beta (TNF-beta) in Patients with Atopic Dermatitis / 대한피부과학회지

BACKGROUND: Atopic dermatitis (AD) is a common inflammatory skin disease. Atopic dermatitis is associated with increased IL-4, IL-5, IL-10 and IL-13 but decreased INF-gamma and TNF production. IL-10 production has been implicated in autoimmunity because of its effect on B-cell proliferation and antibody production. The study of IL-10 gene polymorphism is of interest because of the pivotal role of IL-10 in the regulation of inflammatory and immune responses. TNF-beta significantly upregulates INF-gamma but downregulates IL-5, IL-13 and IgE, which suggests a potential role of TNF-beta in the pathogenesis of atopic dermatitis. OBJECTIVES: We have investigated polymorphism of IL-10 promoter gene and TNF-beta gene. METHODS: Seventy one patients with atopic dermatitis and one hundred and sixty six normal subjects participated in this study with analysis of polymorphism of IL-10 promoter (-1082), (-819) gene and seventy one patients with atopic dermatitis and one hundred and forty one normal subjects participated in the analysis of polymorphism of TNF-beta gene. The patients in this study were recently diagnosed with atopic dermatitis. RESULTS: The frequency of IL-10 promoter (-1082) genotypes (A/A, A/G, G/G), genes (A, G), IL-10 promoter (-819) genotypes (T/T, T/C, C/C) and genes (T, C) did not show any significant difference between atopic dermatitis patients and normal controls. There was no significant difference in the frequency of TNFB genotypes (TNFB*1/TNFB*1, TNFB*1/TNFB*2, TNFB*2/TNFB*2) and genes (TNFB*1, TNFB*2) in patients of atopic dermatitis and normal controls. CONCLUSION: The results of this study suggest that the other regions of the IL-10 promoter gene and TNFB gene should be investigated for polymorphism of atopic dermatitis. And the difference of IL-10 promoter and TNFB gene polymorphism between caucasian and Korean needs to be evaluated.

A Case of Duplication 9p Syndrome: Partial Trisomy 9p

Trisomy 9p syndrome was first described by Rethore, et al in 1970 and about 150 cases have been reported. Trisomy 9p has been reported as either partial or complete. The term "duplication 9p syndrome" instead of "trisomy 9p syndrome" is used since most of the reported patients had only partial duplication rather than the whole arm duplication of 9p. Duplication of 9p syndrome is characterized by growth and developmental retardation, microbrachycephaly, deep and wide set eyes with down-slanting palpebral fissures, "globular" nose, down-turned corners of the mouth, prominent apparently low-set ears, and short fingers and toes with small nails. A 10- month-old male was referred to our department of pediatrics because of hypotonia and delayed development. Karyotype revealed 46, XY, dup(9)(p12p24) by GTC-Banding. We report a case of a duplication 9p syndrome diagnosed by GTC-banding.

Mutations of SCN1B in Generalized Epilepsy with Febrile Seizures Plus(GEFS+) / 대한소아신경학회지

PURPOSE: Febrile seizures affect 2-5% of all children younger than 6 years old. A small proportion of children with febrile seizures later develop epilepsy. Generalized epilepsy with febrile seizures plus(GEFS+) is an important childhood genetic epilepsy syndrome with heterogeneous phenotypes, including febrile seizures(FS) and generalized epilepsies of variable severity. It was reported that the gene locus for GEFS+ exists in the chromosome 19q13.1, and has relationship with a 387 C->G mutation in the voltage- gated sodium channel beta1 subunit(SCN1B) gene. This study is to determine whether there are mutations in children with GEFS+ and FS. METHODS: Eighteen GEFS+ and thirteen FS patients were screened for mutations in the sodium channel beta-subunits SCN1B. The primer pairs used to amplify the exons of SCN1B are given in the supplementary data on the Neurology web site. All exons were amplified by PCR and PCR products were subsequently sequenced. Single-stranded conformation polymorphism(SSCP) was carried out using 8% polyacrylamide gel. RESULTS: Twenty four patients(77%) were younger than 10 years old, three(10%) were between 10 and 14 years old, and four(13%) older than 14 years old. The ratio of female to male was 0.55:1.0. In phenotypes of GEFS+, fourteen patients(88%) had generalized tonic-clonic seizures, one patient(6%) myoclonic seizures and one patient(6%) atonic seizures. In EEG findings of GEFS+, eleven(78%) patients had normal findings, five(28%) patients generalized spike waves and two patients(11%) diffuse slowings. In sequencing and SSCP of PCR products, we could observe added C mutations between 224G and 225C of exon 3 in two unrelated patients with GEFS+. CONCLUSION: We proved the existence of a new mutation of SCN1B in two unrelated patients with GEFS+.

Effect of BaSO4 in Bone Cement on Rat Osteoblast / 대한정형외과연구학회지

PURPOSE: We hypothesize that the presence of barium sulfate debris plays an influential role to deteriorate the balance of bone remodelling around prosthesis via cytotoxic mechanism to osteoblast. MATERIALS AND METHODS: Osteoblasts were obtained from the neonatal rat calvarium, and SiO2, TiO2 , PMMA and BaSO4 particles were prepared for the evaluation of particle induced cytotoxicity to osteoblast. Osteoblasts were grown in DMEM and then were seeded into 6 well culture plates. 1.0wt% solution of each particle was added to culture medium to generate a final concentration of 0.1wt%, and 0.005wt% of various particles in each well, respectively. The measurement of intracellular calcium was conducted using various agonists of calcium. The cell viability assay for osteoblast was performed with MTT reduction assay and the mineralization of the matrix was checked by Von Kossa staining. ELISA kit was used to quantify the level of osteocalcin in osteoblast. RESULTS: BaSO4 significantly lowered the cell viability. All particles except TiO2 increased [Ca(2+)]i transiently, and the rank of differential cytosolic [Ca(2+)]i was in order as follows; SiO2, BaSO4, and PMMA. The mineralization was significantly prohibited in SiO2 and BaSO4(0.1wt%), however the PMMA showed no definite inhibitory effect on bone mineralization. PMMA(0.1wt%) and BaSO4(0.1wt%) showed significantly inhibitory effect on osteocalcin production. CONCOUSION: In higher concentration, BaSO4 has a cytotoxic effect on osteoblast and inhibitory effect of osteocalcin production as well as mineralization of osteoblast. Also, this study has shown that the concentration of intracellular calcium is strongly influenced by exposure to BaSO4 particles in vitro. The effect of BaSO4 on osteoblast observed in this study could have implications for the role of BaSO4 particles on osteoblast function at aseptic loosening of cemented total joint arthroplasty.

p38 MAPK and NF-kappaB are required for LPS-induced RANTES production in immortalized murine microglia (BV-2)

Using murine immortalized microglial cells (BV-2), we examined the regulation of RANTES production stimulated by lipopolysaccharide (LPS), focusing on the role of mitogen-activated protein kinase (MAPK) and nuclear factor (NF)-kappaB. The result showed that RANTES (regulated upon activation of normal T cell expressed and secreted) was induced at the mRNA and protein levels in a dose- and time-dependent manner in response to LPS. From investigations of second messenger pathways involved in regulating the secretion of RANTES, we found that LPS induced phosphorylation of extracellular signal-regulated kinase (Erk), p38 MAPK and c-Jun-N-terminal kinase (JNK), and activated NF-kappaB. To determine whether this MAPK phosphorylation is involved in LPS-stimulated RANTES production, we used specific inhibitors for p38 MAPK and Erk, SB 203580 and PD 98059, respectively. LPS-induced RANTES production was reduced approximately 80% at 25 micrometer of SB 203580 treatment. But PD 98059 did not affect RANTES production. Pyrrolidine-dithiocarbamate (PDTC), NF-kappaB inhibitor, reduced RANTES secretion. These results suggest that LPS-induced RANTES production in microglial cells (BV-2) is mainly mediated by the coordination of p38 MAPK and NF-kappaB cascade.

Molecular cloning and sequencing of rat Cdc42 GTPase cDNA

Cdc42 is a member of the Rho family of small GTP-ase and plays an important role in intracellular signaling pathways regulating cell morphology, motility and stimulation of DNA synthesis. We have isolated cDNA encoding Cdc42 from a rat brain cDNA library using PCR-cloning strategy. The sequence of isolated gene revealed an open reading frame of 576 nucleotides with the potential to encode a protein of 191 amino acids with a predicted molecular weight of 21 kD. The resulting sequence was incorporated into the GenBank with accession number, AF205635. Sequence analysis revealed that overall cDNA sequence identity is 96% with human G25K and 52% with rat Chp, a homologue of the GTPase human Cdc42Hs, and having one nucleotide difference from the mouse Cdc42. However, putative protein sequence was identical to the mouse and human brain Cdc42Hs. On expression of the cDNA in COS-7 cells, a protein molecular weight of 21 kD was detected in immunoblotting using anti-human Cdc42 antibodies. Therefore, these results suggest that the cDNA we are reporting is most likely the rat homologue of the GTPase human Cdc42.

Reactive Oxygen Species Generation of Refractory Ceramic Fiber and Rock Wool-Induced Alveolar Macrophage and Associated Signal Transduction Pathway / 대한산업의학회지

OBJECTIVES: It is known that the high fibrogenecity of particles is connected with their cytotoxicity for macrophages. Although the molecular mechanism leading to fiber-induced fiber-induced cytotoxicity is still not clear, several mechanism have been suggested. The release of reactive oxygen species (ROS) from activated alveolar macrophages (AM) by dust have been suggested as a possible mechanism of particle-induced cell damage. But the mechanism which man-made vitreous fiber (MMVF) induces the production of ROS in AM is still not clear. In this study, we evaluated the relationship between ROS production and lactate dehydrogenase (LDH) release from alveolar treated with refractory ceramic fiber (RF2) or rock wool (RW1) and signal transduction path-way of ROS production in RF2 or RW1 exposed AM. METHODS: We investigated LDH release from MMVF-stimulated AM for index of cytotoxicity. To determine what kind of signal transduction pathways are involved in MMVF-stimulated ROS generation, we used some drugs which have an effect on the signal transduction pathway. RESULTS: RF2 and RW1 induced increase of LDH release with dose-dependent manner with RF2 having greater effect than RW1. There was a dose-dependent increase in the production of ROS by RF2 or RW1. At all level of concentration,. RF2 induced more ROS production than RW1. Inhibitors of PKC (bisindolylmaleimide), PLC (U73122 and neomycine) and PTK (genistein and erbstatin) suppressed RF2 or RW1-induced ROS production. CONCLUSION: There was significant correlation between LDH release and ROS production from AM treated with RF2 or RW1. RF2 and RW1 induced ROS generation through protein kinase C (PKC), phospholipase C (PLC) and protein tyrosin kinase (PTK) pathways.

Hydroxyl radical-mediated commitment of HL-60 cells to differentiation: Modulation of differentiation process by phosphodiesterase inhibitors

Ms report shows that hydroxyl radical, generated by a Fenton reaction involving adenosine 5'-diphosphate/Fe2+ complex (5-15 micrometer) and H2O2 (2 micrometer), induced differentiation of HL-60 cells in a dose- and time-dependent manner. This is evidenced by the increases in 12-O-tetradecanoylphorbol 13-acetate- and fMLP-stimulated superoxide production capability. The cells exposed to hydroxyl radical for defined periods (24~96 hr) continued to differentiate even after the hydroxyl radical generating system had been removed. The differentiated cells displayed fMLP-stimulated calcium mobilization and increased expression of myeloid-specific antigen CD11b and CD14. The extent of the differentiation was markedly reduced by desferrioxamine (100micrometer), dimethylthiourea (5 mM), N,N'-diphenyl-1,4-phenylenediamine (2 micrometer), and N-acetyl-L-cysteine (5 mM). The induction of differentiation by hydroxyl radical was enhanced by 3-isobutyl-1-methylxanthine (200 micrometer) and Ro-20-1724 (8 micrometer), and inhibited by dipyridamole (2 micrometer). These results suggest that hydroxyl radicals may induce commitment of HL-60 cells to differentiate into more mature cells of myelomonocytic lineage through specific signal-transduction pathway that is modulated by phosphodiesterase inhibitors.

Drug Interaction in Renal Excretion

No abstract available.

Endothelin increases intracellular free calcium in isolated rat nephron

In the freshly isolated rat nephron, the effect of endothelin-1, -2 and -3 (ET-1, -2 and -3) on cytosolic free calcium concentration ((Ca2+)i) was determined using the fluorescent indicator Fura-2/AM. (Ca2+)i increase was investigated in 9 parts of the single nephron including glomerulus (Glm), S1, S2, S3, Cortical and medullary thick ascending limb and cortical (CCT) and outer medullary collecting tubule (OMCT). Endothelins increased (Ca2+)i in Glm (ET-1; 127+/-17%, ET-2; 93+/-5%, ET-3; 169+/-17%), CCT (ET-1; 30+/-6%, ET-2; 38+/- 19%, ET-3; 158+/-18%) and OMCT (ET-1; 197+/- 11%, ET-2; 195+/- 11%, ET-3; 215+ 37%) at 10(-7) M. In OMCT, ET-1 and ET-2 increased (Ca2+)i in a dose-dependent manner (10(-10) ~ 10(-6) M). To the contrary, ET-3-induced (Ca2+)i rise was begun from 10(-12) M. BQ-123Na, an antagonist of ETA receptor, at 10(-4) M inhibited about 30% of (Ca2+)i rise induced by ET-1 and -3. Binding experiments using (125I)ET-3 showed the existence of ETB receptor in OMCT. This binding was replaced by ET-1, ET-2 or ET-3 by the almost same degree but not by angiotensin II or vasopressin.