Biomedical subjects

F Tanabe

Publications and source records attributed to F Tanabe.

At least 19 recordsLinked to original sources

PubMed2006

Diffusion tensor feature in vasogenic brain edema in cats.

We investigated the correlation between the changes in diffusion tensor magnetic resonance imaging, regional water content, and tissue ultrastructure after vasogenic brain edema induced by cortical cold lesioning. In this cat model, E3 in the white matter was dominantly increased while fractional anisotropy (FA) was significantly decreased 8 hours after cortical cold lesioning. This finding indicates that water diffusion in the cortical white matter mainly increased perpendicularly rather than parallel to the direction of the nerve fibers. Additionally, in the area where edema is mild or moderate (tissues with water content of 65% to 75%), FA in the chronic phase was significantly lower than that in the acute phase. Histological examination demonstrated disordered arrangement of nerve fibers, highly dissociated neuronal fibers due to extracellular accumulation of protein rich-fluid, and enlarged interfiber spaces in the acute phase.

Animals↗

PubMed2004

Increased CCR4 expression on circulating CD4(+) T cells in ankylosing spondylitis, rheumatoid arthritis and systemic lupus erythematosus.

Previous studies have suggested that CCR4 is particularly important in the selective recruitment of various subsets of leucocytes in rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). In this study, we examined the percentage of CD4(+)/CCR4(+) T cells within circulating lymphocytes in active ankylosing spondylitis (AS), RA and SLE patients. The clinical significance of CCR4 expression as well as possible associations between the expression and serum levels of tumour necrosis factor (TNF)-alpha, interferon (IFN)-gamma and interleukin (IL)-10 were also examined. Our results showed that the percentage of CD4(+)/CCR4(+) T cells was significantly elevated in AS and RA patients as compared with normal controls. The percentage was also significantly higher in SLE patients who had received no treatment with glucocorticoids or cytotoxic drugs (untreated SLE) than that in controls. In addition, the percentage of CD4(+)/CCR4(+) T cells showed significant positive correlations with the Bath ankylosing spondylitis disease activity index (BASDAI) in AS and with the SLE disease activity index (SLEDAI) in untreated SLE. Of all the cytokines examined, the elevated serum IL-10 level was closely correlated with the percentage of CD4(+)/CCR4(+) T cells in AS, RA and untreated SLE. These results suggest that CCR4 may be crucial in the pathogenesis of AS, RA and SLE. The percentage of CD4(+)/CCR4(+) T cells can serve as a useful marker for the activity of AS and untreated SLE.

Adult↗

PubMed2003

Recovery of apparent diffusion coefficient after embolic stroke does not signify complete salvage of post-ischemic neuronal tissue.

BACKGROUND AND PURPOSE: It has been shown in previous studies that recovery of apparent diffusion coefficient (ADC) of water is not necessarily associated with a reversal of tissue damage. We examined the relationships between temporal ADC change and histological outcome after embolic stroke in rat using an experimental MRI scanner. SUBJECTS AND METHODS: Male Wistar rats underwent embolization of the right middle cerebral artery with autologous clot. ADC and relative cerebral blood flow (rCBF) were measured consecutively for 3 hours after embolization. The brains were prepared for histological examination. RESULTS: Transient decline of ADC was observed during the initial 2 hours after embolization. In these areas, serial rCBF measurement revealed incomplete recovery. In some other areas, ADC decrease without rCBF recovery was observed during 3 hours postischemia. Histological examination revealed infarction in areas with persistent ADC decrease. Scattered neuronal death was noticeable in areas with a transient--in some areas less than 0.5 hour--ADC decrease. CONCLUSION: Consecutive MRI analysis demonstrated postischemic transient ADC decrease in an embolic stroke model of rat. The normalization of ADC does not signify normalization of postischemic tissue, since the areas often evolve postischemic neuronal death at a later time.

Animals↗

PubMed2001

A thiol proteinase inhibitor, E-64-d, corrects the abnormalities in concanavalin A cap formation and the lysosomal enzyme activity in leucocytes from patients with Chediak-Higashi syndrome by reversing the down-regulated protein kinase C activity.

We have reported previously that the abnormally down-regulated protein kinase C (PKC) causes cellular dysfunction observed in natural killer (NK) cells, polymorphonuclear leucocytes (PMNs) and fibroblasts from beige mouse, an animal model of Chediak-Higashi syndrome (CHS). Here we show that the abnormal down-regulation of PKC activity also occurs in Epstein-Barr (EB) virus-transformed cell lines from CHS patients. When CHS cell lines were stimulated with concanavalin A (Con A) for 20 min, the membrane-bound PKC activity declined markedly, whereas that in control cell lines increased. We found that E-64-d, which protects PKC from calpain-mediated proteolysis, reversed the declined PKC activity and corrected the increased Con A cap formation to almost normal levels in CHS cell lines. We confirmed that the dysregulation of PKC activity also occurred in peripheral blood mononuclear leucocytes (PBMC) from CHS patients and that E-64-d corrected both the declined PKC activity and increased Con A cap formation. E-64-d also corrected the reduced lysosomal elastase and cathepsin G activity in CHS cell lines. In contrast, chelerythrin, a specific inhibitor of PKC, and C2-ceramide, which promotes PKC breakdown induced by calpain, increased Con A cap formation and inhibited both elastase and cathepsin G activity in normal cell lines. Moreover, we found that ceramide production in CHS cell lines increased significantly after Con A stimulation, which coincides with our previous observation in fibroblasts from CHS mice. These results suggest an association between ceramide-induced PKC down-regulation and the cellular dysfunctions in CHS.

Calpain↗

PubMed2000

Interleukin 18 and interleukin 1beta production is decreased in HIV type 1-seropositive hemophiliacs but not in HIV type 1-seropositive nonhemophiliacs.

In Japan, the proportion of hemophiliacs infected with human immunodeficiency virus type 1 (HIV-1) is 40%, whereas more than 90% are infected with hepatitis C virus (HCV). To evaluate the immunological status of hemophiliacs infected with HIV-1, we investigated the pattern of cytokine production in peripheral blood mononuclear cells (PBMCs) of HIV-1-seropositive and -seronegative hemophiliacs, HIV-1-seropositive non-hemophiliacs, and healthy individuals. The production of IL-18 and IL-1beta from PBMCs stimulated with Staphylococcus aureus Cowan strain 1 (SAC) in the HIV-1-seropositive hemophiliacs was significantly decreased in comparison with the other groups. On the other hand, IL-12 production in both HIV-1-seropositive groups was significantly lower than in HIV-1-seronegative groups. TNF-alpha and IL-6 production was similar among the four groups. In contrast, plasma levels of TGF-beta1 were increased in HIV-1-seropositive hemophiliacs, HIV-1-seropositive nonhemophiliacs, and HIV-1-seronegative hemophiliacs, with the highest levels being in HIV-1-seropositive hemophiliacs, suggesting that coinfection with HIV-1 and HCV increases the level of plasma TGF-beta in HIV-1-seropositive hemophiliacs. Treatment of PBMCs from healthy individuals with TGF-beta1 inhibited IL-18 and IL-1beta production without affecting IL-6, IL-10, or TNF-alpha production. Suppression of the expression of caspase 1 mRNA, which is known to be an IL-1beta-converting enzyme and which also cleaves the precursor of IL-18, was observed in the SAC-stimulated PBMCs from healthy individuals after treatment with TGF-beta1 and in the SAC-stimulated PBMCs from HIV-1-seropositive hemophiliacs, suggesting that the decreased production of IL-18 and IL-1beta in HIV-1-seropositive hemophiliacs may be related to the downregulation of caspase 1 mRNA induced by high levels of TGF-beta1 in plasma.

Adolescent↗

PubMed2000

Abnormal down-regulation of PKC is responsible for giant granule formation in fibroblasts from CHS (beige) mice--a thiol proteinase inhibitor, E-64-d, prevents giant granule formation in beige fibroblasts.

We have previously reported that the abnormally rapid down-regulation of protein kinase C (PKC) activity is responsible for the cellular dysfunction in natural killer (NK) cells and polymorphonuclear leukocytes (PMNs) from Chediak-Higashi syndrome (beige) mice. In this report, we examined whether the down-regulation of PKC is associated with giant granule formation in fibroblasts from beige mice. In cultured beige fibroblasts, the membrane-bound PKC activity declined significantly after phorbol ester stimulation. We found that E-64-d, which is a thiol proteinase inhibitor and protects PKC from calpain-mediated proteolysis, reversed the declined PKC activity and prevented giant granule formation in beige fibroblasts. Moreover, E-64-d corrected the reduced lysosomal elastase and cathepsin G activity in beige fibroblasts. In contrast, specific PKC inhibitors, chelerythrin and calphostin C, promoted giant granule formation in normal fibroblasts. We also demonstrate that ceramide production is enhanced in beige fibroblasts and is involved in the rapid down-regulation of PKC. These results suggest that the accelerated breakdown of PKC observed in beige fibroblasts is caused by enhanced ceramide production and is also responsible for giant granule formation.

Animals↗

PubMed2000

Protein kinase C is involved in cardioprotective effects of ischemic preconditioning on infarct size and ventricular arrhythmia in rats in vivo.

Protein kinase C (PKC) has been known to play an important role in ischemic preconditioning (IP). This study was designed to examine whether the translocation of PKC is associated with the cardioprotective effects of IP in vivo on infarct size and ventricular arrhythmias in a rat model. Using anesthetized rats, heart rate, systolic blood pressure, infarct size and ventricular arrhythmias during 45 min of coronary occlusion were measured. PKC activity was assayed in both the cytosolic and cell membrane fraction. Brief 3-min periods ofischemia followed by 10 min ofreperfusion were used to precondition the myocardium. Calphostin C was used to inhibit PKC. Infarct size was significantly reduced by IP (68.1 (2.5)%, mean (S.E.) vs. 45.2 (3.4)%, p < 0.01). The reduction in infarct size by IP was abolished by pretreatment with calphostin C. The total number of ventricular premature complex (VPC) during 45 min of coronary occlusion was reduced by IP (1474 (169) beats/45 min vs. 256 (82) beats/45 min, p < 0.05). The reduction the total number of VPC induced by IP was abolished by the administration of calphostin C before the episode of brief ischemia. The same tendency was observed in the duration of ventricular tachycardia and the incidence of ventricular fibrillation. PKC activity in the cell membrane fraction transiently increased immediately after IP (100 vs. 142%, p < 0.01) and returned to baseline 15 min after IP. Pretreatment with calphostin C prevented the translocation of PKC. The translocation of PKC plays an important role in the cardioprotective effect of IP on infarct size and ventricular arrhythmias in anesthetized rats.

Animals↗

PubMed1999

Reverse transcriptase (RT)-independent as well as RT-dependent HIV-1 replication exists in syncytia following cell fusion.

We studied the role of reverse transcriptase (RT) in human immunodeficiency virus (HIV)-1 replication in syncytia following cell fusion. A chronically HIV-1-infected MOLT-4 (MOLT-4/IIIB) cells allow HIV-1 replication and induce syncytium formation between uninfected MOLT-4 cells. AZT (3'-azido-3'-deoxythymidine, 1 microM) inhibited neither HIV-1 replication in MOLT-4/IIIB cells nor the syncytium formation induced by concultivation of MOLT-4/IIIB cells with uninfected MOLT-4 cells. In the supernatant of the syncytium containing culture a remarkably higher titer of p24 antigen was produced than in that of MOLT/IIIB cell culture. AZT inhibited p24 antigen production by HIV-1 in the syncytia to levels to comparable to that in MOLT-4/IIIB cells which were treated with AZT. In addition, p24 production by HIV-1 in the syncytia formed by cocultivation of CL-2 cells, which are chronically infected with HIV-1 but lack functional RT, with uninfected MOLT-4 cells was not different from that in CL-2 cells alone. The results suggest that HIV-1 RT plays an important role in HIV-1 replication within the syncytia but an RT-independent replication process which is essential for syncytium formation also exists in the syncytia. These results indicate that not only RT inhibitors but also inhibitors of syncytium formation are essential for anti-HIV therapy.

Cell Line↗

PubMed1998

HIV type 1 Tat protein inhibits interleukin 12 production by human peripheral blood mononuclear cells.

HIV-1 Tat protein, which trans-activates HIV-1 expression, exerts many effects on host immune function. Meanwhile, PBMCs and pulmonary macrophages from HIV-1-infected patients produce only a small amount of IL-12, which plays an essential role in the development of helper T type 1 (Th1) cells, and in the generation of cytotoxic T lymphocytes. We examined the possibility that Tat suppresses IL-12 production by PBMCs from healthy donors. Tat significantly inhibited IL-12 production by human PBMCs stimulated with Staphylococcus aureus Cowan 1 strain (SAC) at concentrations between 5 and 40 ng/ml. Immunoabsorption by using polyclonal antibody to Tat abolished the suppression of the IL-12 production by Tat. Tat at the same concentrations did not affect IL-10, IL-6, or TNF-alpha production. Other HIV-1 proteins (Nef and gp120) did not influence IL-12 production. Tat also suppressed the expression of mRNA encoding the p40 chain of IL-12, whereas it did not affect the expression of mRNA encoding IL-10 and beta-actin. IL-12 production by monocytes, separated from PBMCs by the adhesion method, was also inhibited by Tat. These results suggest that Tat protein is one of the main causes of decreased IL-12 production by PBMCs (mostly by monocytes) from HIV-1-infected individuals.

Amino Acid Sequence↗

PubMed1998

Ceramide promotes calpain-mediated proteolysis of protein kinase C beta in murine polymorphonuclear leukocytes.

Ceramide has been recognized as an important second messenger in intracellular signaling. We demonstrate here that ceramide promotes the down-regulation of protein kinase C (PKC) activity in phorbol ester-stimulated murine polymorphonuclear leukocytes (PMNs). As reported previously, treatment of PMNs with phorbol ester caused a translocation of PKC from the cytosolic to the membrane fractions. When PMNs were pretreated with cell-permeable ceramide analogue, C2-ceramide, the membrane-associated PKC activity was rapidly down-regulated by phorbol ester stimulation. E64-d, a potent inhibitor of calpain which proteolyzes PKC, eliminated the rapid down-regulation of PKC activity. By hydroxyapatite column chromatography and Western blotting, the predominant PKC isoform was PKC beta with a small amount of PKC alpha in murine PMNs. We found that ceramide strikingly promoted calpain-mediated proteolysis of PKC beta in vitro. Ceramide was also shown to inhibit [3H]phorbol 12,13-dibutyrate(PDBu) binding to PKC beta. Moreover, we show that ceramide stimulates PKC beta autophosphorylation. These results suggest that ceramide directly activates PKC beta and promotes calpain-mediated proteolysis in murine PMNs.

Animals↗

PubMed1997

A simple and sensitive bioassay for the detection of human interleukin-18/interferon-gamma-inducing factor using human myelomonocytic KG-1 cells.

Interleukin-18 (IL-18)/interferon-gamma-inducing factor (IGIF) is a novel cytokine which plays an important role in Th1 responses. Here we describe a simple, sensitive bioassay for human IL-18 using the human myelomonocytic cell line, KG-1, which produces IFN-gamma in response to human IL-18. IFN-gamma production induced by human IL-18 was completely blocked by an antibody against human IL-18. Human IL-18 could be measured in a concentration range from approximately 100 to 10,000 pg/ml, and intra- and inter-assay coefficient variations were both below 15%. It was possible to measure human IL-18 in human serum, cell lysate or culture supernatant by this bioassay. Thus, the human IL-18 bioassay can be expected to be useful in the investigation of the relationship between human IL-18 and various diseases or in analyzing the mechanisms of human IL-18 secretion from IL-18 producing cells.

Animals↗

PubMed1997

Cloning and expression of five myb-related genes from rice seed.

Three elements in the promoter of rice glutelin genes are important for their endosperm specific expression. One of these, an AACA motif, has been shown to be a negative regulator in non-seed tissues and has a similarity to the barley gibberellin responsive element recognized by MYB-like DNA binding proteins. A cDNA library constructed from immature rice seed was screened using two types of myb gene probes to isolate cDNA clones representing genes encoding MYB-like DNA binding proteins that may recognize the AACA motif in rice glutelin gene promoter. We obtained four cDNA clones encoding MYB-related proteins, Oryza sativa MYB (OSMYB) 1-4, using the maize C1 probe. Another myb-like clone, Osmyb5, was obtained by screening a rice seed cDNA library with probes designed to recognize the AACA-like binding domain in GAMYB and PHMYB3. RT-PCR was used to analyze Osmyb expression during rice seed development and their presence in other rice tissues, as it was not possible to detect these mRNAs by conventional Northern analysis. RT-PCR analysis showed that Osmyb2, Osmyb3 and Osmyb5 genes were expressed in all tissues examined. In seed, the mRNA levels of Osmyb1 and Osmyb4 genes reached a maximum at 14 days after flowering (DAF), suggesting that these genes may play a role in seed maturation. As Osmyb5 exhibits a high similarity to the regions in both GAMYB and PHMYB3, which can bind to the AACA motif, there is a possibility that the OSMYB5 protein may bind to the AACA motif of glutelin genes.

Amino Acid Sequence↗

PubMed1996

Cloning of the cDNA for human IFN-gamma-inducing factor, expression in Escherichia coli, and studies on the biologic activities of the protein.

We have recently reported that a novel molecule, murine IFN-gamma-inducing factor (IGIF) produced by mouse liver cells, possesses potent biologic activities, including the induction of IFN-gamma production by spleen cells and the enhancement of NK cell cytotoxicity. In this paper, we report on the isolation of human IGIF cDNA clones from normal human liver cDNA libraries using murine IGIF cDNA as a probe. The amino acid sequence deduced from the human cDNA clones indicated a 193-amino acid precursor peptide and revealed 65% homology with that of murine IGIF. The amino acid sequence of IGIF also included an IL-1 signature-like sequence. Subsequently, the cloned cDNA was expressed in Escherichia coli, and preliminary studies on the biologic activities of the recombinant protein were performed. The recombinant human IGIF induced IFN-gamma production by mitogen-stimulated PBMC and enhanced NK cell cytotoxicity, in a manner similar to murine IGIF. In addition, recombinant human IGIF also augmented granulocyte-macrophage-CSF production and decreased IL-10 production, but had no effect on IL-4 production by Con A-stimulated PBMC. Based on these pleiotropic effects of IGIF, we propose that this novel cytokine be designated as IL-18.

Adult↗

PubMed1996

Interferon-gamma-inducing factor enhances T helper 1 cytokine production by stimulated human T cells: synergism with interleukin-12 for interferon-gamma production.

The novel cytokine interferon-gamma-inducing factor (IGIF) augments natural killer (NK) cell activity in cultures of human peripheral blood mononuclear cells (PBMC), similarly to the structurally unrelated cytokine interleukin (IL)-12. IGIF has been found to enhance the production of interferon-gamma (IFN-gamma) and granulocyte/macrophage colony-stimulating factor (GM-CSF) while inhibiting the production of IL-10 in concanavalin A (Con A)-stimulated PBMC. In this study, when anti-CD3 monoclonal antibody (mAb)-stimulated human enriched T cells were exposed to IGIF, the cytokine dose-dependently enhanced the proliferation of the cells and this could be completely inhibited by a neutralizing antibody against IL-2 at lower concentrations of IGIF. Neutralizing antibody against IFN-gamma had only insignificant inhibitory effects on T cell proliferation at higher concentrations of IGIF. Enzyme-linked immunosorbent assays (ELISA) revealed that, like PBMC, T cells exposed to IGIF produced large amounts of IFN-gamma; however, changes in the production of IL-4 and IL-10 were minimal. IGIF, but not IL-12, significantly enhanced IL-2 and GM-CSF production in T cell cultures, as determined by CTLL-2 bioassay and ELISA, respectively; however, both IGIF and IL-12 enhanced IFN-gamma production by the T cells. When T cells were exposed to a combination of IGIF and IL-12, a synergistic effect was observed on the production of IFN-gamma, but not on production of IL-2 and GM-CSF. In conclusion, IGIF enhances T cell proliferation apparently through an IL-2-dependent pathway and enhances Th1 cytokine production in vitro and exhibits synergism when combined with IL-12 in terms of enhanced IFN-gamma production but not IL-2 and GM-CSF production. Based on structural and functional differences from any known cytokines, it was recently proposed that this cytokine be designated interleukin-18.

Adult↗

PubMed1996

Characterization of common cis-regulatory elements responsible for the endosperm-specific expression of members of the rice glutelin multigene family.

Glutelin is the most abundant storage protein in rice, which is expressed specifically in the endosperm of maturing seed. Glutelin is encoded by about 10 genes per haploid genome, which are clearly divided into two subfamilies (GluA and GluB). Most of them are coordinately expressed during seed maturation in spite of the remarkable divergence in the 5'-flanking regions between members of two subfamilies. In order to identify the common regulatory mechanisms responsible for the endosperm-specific expression, various cis-regulatory elements in the 5'-flanking region of the glutelin GluB-1 gene were characterized by studying the expression of chimeric genes that consisted of the sequentially deleted or mutagenized promoter and a beta-glucuronidase (GUS) reporter gene in transgenic tobacco seeds. The essential cis-regulatory elements governing the spatially and temporally specific expression of the glutelin gene expression were located within the first 245 bp of the promoter region of the GluB-1 gene from the site of initiation of transcription. The AACA motif between positions -73 and -61 common to all the six genes for glutelin sequenced to date and is repeated between positions -212 and -200 is implicated in the seed-specific expression. The GCN4 motif between positions -165 and -158 and between positions -96 and -92 that is conserved at homologous sites in all the members of glutelin gene family is also involved in the seed-specific regulation. However, both are required for the high level of seed-specific expression, because deletion of the region containing one set of both elements or substitution mutation of the AACA or GCN4 motif substantially reduced the activity. As a whole, our results suggest the combinatorial interaction of the elements in regulation of the glutelin gene expression.

Base Sequence↗

PubMed1996

[The influence of pregnancy and delivery on the climacteric symptoms].

This study was undertaken to investigate the influence of past pregnancy and delivery on the perimenopausal status in 144 women (48-52 years of age). Individual interviews to ascertain the personal profile, medical history, events at pregnancy, delivery and puerperium, and the kind and severity of climacteric symptoms were held. The subjects were divided into two groups by means of a simplified menopausal index (SMI): group A had climacteric symptoms (SMI > 50) and those in group B had mild symptoms (SMI < or = 50). The analysis of the principal components, and the correlation among the variables revealed that three factors--the impression and events at past pregnancies and deliveries, reproductive functions, and the psycho-character properties--had a significant influence on the status at the perimenopause, but the social-environmental factors appeared to have no significant influence on the severity of climacteric symptoms.

Climacteric↗

PubMed1995

A novel costimulatory factor for gamma interferon induction found in the livers of mice causes endotoxic shock.

Administration of monoclonal anti-CD3 antibody to mice treated with Propionibacterium acnes induced secretion of a high level of gamma interferon (IFN-gamma) into the circulation system, while it induced no significant release in untreated mice. In order to analyze this high-level induction of IFN-gamma in these bacterium-treated mice, we investigated the factors that might be involved. An activity that induces IFN-gamma in T cells was observed in the liver extracts of mice treated with P. acnes and subsequently challenged with lipopolysaccharide. Here, we purified an IFN-gamma-inducing factor from the liver extract to homogeneity and characterized it. Its molecular mass was 18 to 19 kDa, and its pI was 4.9. The amino acid sequence of the NH2-terminal portion was determined and shown to have no similarities to any protein in the EMBL, GenBank, and PIR data bases. The same molecule was also demonstrated in the serum factor that was previously reported to have an IFN-gamma-inducing activity and to have an apparent molecular mass of 75 kDa. Moreover, the activity of this serum factor was recovered in the fraction containing the 18- to 19-kDa protein under reducing conditions and was shown to have the same NH2-terminal amino acid sequence as that of the factor from the liver extract. In addition to the ability to induce IFN-gamma, this protein augmented T-cell proliferation and NK activity in the spleen cells. Thus, several of its biological activities were apparently similar to those of interleukin-12. These results indicated that this novel protein, which exhibited marked costimulatory activity on IFN-gamma production in vitro, was elevated vivo in response to P. acnes treatment. This factor, probably released from the producing cells by lipopolysaccharide stimuli, may be involved in the high-level induction of IFN-gamma in the P. acnes-treated mice.

Amino Acid Sequence↗

PubMed1994

[Method of DNA extraction and mecA, femA and PBP2' in multi-drug resistant bacterial strains].

Recently, it has become more important to establish rapid and reliable methods for identifying bacterial species and their drug resistances because of the high incidence of nosocomial infection caused by multi-drug resistant bacteria. At first, several enzymes were tested to evaluate the efficacy of DNA extraction. N-acetylmuramidase, lysozyme and achromopeptidase were most effective to extract DNA from E. faecalis, E. faecium and S. aureus, respectively. After achromopeptidase extraction, the mecA gene was amplified by polymerase chain reaction (PCR) in clinically isolated MRSA (95 strains), MSSA (66), MRSE (methicillin-resistant S. epidermidis, 37), MSSE (methicillin-sensitive S. epidermidis, 1), S haemolyticus(5), S.hominis(1) and others (Enterococcus, Pseudomonas, and Streptococcus, total 45). PCR products were analyzed by agarose gel electrophoresis. The positive rates were 95% (MRSA), 1.5% (MSSA), and 97% (MRSE). The mecA gene was also positive in 2/2 of methicillin-resistant S.haemolyticus and 2/3 of methicillin-sensitive S.haemolyticus and 1/1 of methicillin-resistant S.hominis. The mecA gene was not detected in 45 non-Staphylococcal strains. MecA and femA gene by PCR and PBP 2' by IRMA were further detected in newly isolated MRSA (20 strains), MSSA(20), MRSE(14), MSSE(1) and S.simulans(2). Complete correlation between MPIPC susceptibility and mecA were found. The femA gene was positive in 39/40 of S. aureus, and 0/14 of S.epidermidis, 2/3 of S.simulans. PBP2' were positive in 20/20 of MRSA, 0/20 of MSSA, 14/14 of MRSE, 0/1 of MSSE, 1/1 of methicillin-resistant S.simulans, and 0/2 of methicillin-sensitive S.simulans. In conclusion, diagnoses of MRSA by simultaneous detection of mecA and femA gene as well as PBP2' are similarly useful because of their specificity and rapidity.

Bacterial Proteins↗