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Arakawa Y, Kang S, Watanabe J, Konishi GI. Assembly of thioether-containing rod-like liquid crystalline materials assisted by hydrogen-bonding terminal carboxyl groups. RSC Adv 2015. [DOI: 10.1039/c4ra15300f] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
A hydrogen-bonding-tolane-based liquid crystalline material with an alkylsulfanyl group was synthesized, which exhibited a long-range correlated mesophase compared with analogs with alkyl and alkoxy groups.
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Kido N, Ohta M, Iida K, Hasegawa T, Ito H, Arakawa Y, Komatsu T, Kato N. Partial deletion of the cloned rfb gene of Escherichia coli O9 results in synthesis of a new O-antigenic lipopolysaccharide. J Bacteriol 1989; 171:3629-33. [PMID: 2472376 PMCID: PMC210104 DOI: 10.1128/jb.171.7.3629-3633.1989] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The rfb gene, involved in the synthesis of the O-specific polysaccharide (a mannose homopolymer) of Escherichia coli O9 lipopolysaccharide (LPS), was cloned in E. coli K-12 strains. The O9-specific polysaccharide covalently linked to the R core of K-12 was extracted from the K-12 strains harboring the O9 rfb gene. All the other genes required for the synthesis of rfe-dependent LPS are therefore considered to be present in the K-12 strains. It was found that bacteria harboring some clones with deletions of the ca. 20-kilobase-pair (kbp) BglII-StuI fragment no longer synthesized the O9-specific polysaccharide. However, bacteria harboring clones del 21, del 22, and del 25, which carry deletions of the 10-kbp PstI-StuI fragment, synthesized an O-specific polysaccharide antigenically distinct from E. coli O9 LPS. Although this new O-specific polysaccharide consisted solely of mannose and the mannose residues were combined only through alpha-1,2 linkage, it was still composed of a repeating oligosaccharide unit, possibly a trisaccharide unit,----2)alpha Man-(1----2)alpha Man-(1----2)alpha Man-(1----. It is therefore likely that this new O-specific polysaccharide was derived from a part of the O9-specific polysaccharide----3)alpha Man-(1----3)alpha Man-(1----2)alpha Man-(1----2)alpha Man-(1----2)alpha Man-(1----and that the deleted part of the clones was responsible for the synthesis of alpha-1,3 linkages of the O9-specific polysaccharide.
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Tanaka T, Horii T, Shibayama K, Sato K, Ohsuka S, Arakawa Y, Yamaki K, Takagi K, Ohta M. RobA-induced multiple antibiotic resistance largely depends on the activation of the AcrAB efflux. Microbiol Immunol 1997; 41:697-702. [PMID: 9343820 DOI: 10.1111/j.1348-0421.1997.tb01913.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
RobA is a member of the XylS/AraC subfamily of DNA binding proteins, and when overexpressed, it induces multiple antibiotic resistance in Escherichia coli. In this study, we introduced a multicopy robA plasmid (pMEP1) and its derivative into OmpF mutants and an AcrAB-deficient mutant. We found that a decrease in susceptibility to multiple antibiotics in these OmpF mutants when pMEP1 was introduced did not depend on OmpF porin expression. Interestingly, a delta ompF mutant (TK007) became more sensitive when pMEP1 was introduced. Moreover, no effect of RobA on the induction of multiple antibiotic resistance in an acrA1- mutant was observed. Therefore, we conclude that the multiple antibiotic resistance induced by the overexpression of RobA largely depends on the activation of the AcrAB efflux, as well as the activation of micF.
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Nakai K, Win KM, Oo SS, Arakawa Y, Abe K. Molecular characteristic-based epidemiology of hepatitis B, C, and E viruses and GB virus C/hepatitis G virus in Myanmar. J Clin Microbiol 2001; 39:1536-9. [PMID: 11283083 PMCID: PMC87966 DOI: 10.1128/jcm.39.4.1536-1539.2001] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
We carried out a molecular characteristic-based epidemiological survey of various hepatitis viruses, including hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis E virus (HEV), and GB virus C (GBV-C)/hepatitis G virus (HGV), in Myanmar. The study population of 403 subjects consisted of 213 healthy individuals residing in the city of Yangon, Myanmar, and the surrounding suburbs and 190 liver disease patients (155 virus-related liver disease patients and 35 nonviral disease patients). The infection rates of the viruses among the 213 healthy subjects were as follows: 8% for HBV (16 patients), 2% for HCV (4 patients), and 8% for GBV-C/HGV (17 patients). In contrast, for 155 patients with acute hepatitis, chronic hepatitis, liver cirrhosis, or hepatocellular carcinoma, the infection rates were 30% for HBV (46 patients), 27% for HCV (41 patients), and 11% for GBV-C/HGV (17 patients). In the nonviral liver disease group of 35 patients with alcoholic liver disease, fatty liver, liver abscess, and biliary disease, the infection rates were 6% for HBV (2 patients), 20% for HCV (7 patients), and 26% for GBV-C/HGV (9 patients). The most common viral genotypes were type C of HBV (77%), type 3b of HCV (67%), and type 2 of GBV-C/HGV (67%). Moreover, testing for HEV among 371 subjects resulted in the detection of anti-HEV immunoglobulin G (IgG) in 117 patients (32%). The age prevalence of anti-HEV IgG was 3% for patients younger than 20 years and 30% or more for patients 20 years of age or older. Furthermore, a high prevalence of anti-HEV IgG (24%) was also found in swine living together with humans in Yangon. These results suggest that these hepatitis virus infections are widespread in Myanmar and have led to a high incidence of acute and chronic liver disease patients in the region.
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Arakawa Y, Wada O, Yu TH, Iwai H. Simultaneous determination of trialkyltin homologues in biological materials. J Chromatogr A 1981; 216:209-17. [PMID: 7320105 DOI: 10.1016/s0021-9673(00)82349-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Taking advantage of the high sensitivity of an electron capture detector to alkyltin halides, an analytical method has been developed for the simultaneous determination of trialkyltin homologues in biological materials. Trialkyltins were purified as chlorides from tissues by simultaneous extraction with hydrochloric acid and ethyl acetate, replacement of the extraction solution with n-hexane and stepwise elution with n-hexane-ethyl acetate on a silica gel column. Alternatively, gas chromatographic analysis was carried out on 20% DEGS-HG at temperatures from 100 to 120 degrees C. Detection limits reached 1 x 10(-12) g for trialkyltin chlorides. The recoveries of trialkyltins added to various tissues at the 50-pmole level ranged from 97 to 106%. By in vivo studies, it was confirmed that this method is rapid, sensitive and applicable to biomaterials containing more than 1 ng trialkyltins per gram of tissue.
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Arakawa Y, Kikuta K, Hojo M, Goto Y, Ishii A, Yamagata S. Milrinone for the treatment of cerebral vasospasm after subarachnoid hemorrhage: report of seven cases. Neurosurgery 2001; 48:723-8; discussion 728-30. [PMID: 11322432 DOI: 10.1097/00006123-200104000-00004] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVE The intra-arterial infusion of papaverine has been used for dilation of spastic cerebral vessels after aneurysmal subarachnoid hemorrhage, although its efficacy is controversial. Milrinone is an inotropic drug that dilates vessels by phosphodiesterase inhibition in a mechanism similar to that of papaverine. We examined the effects of intra-arterial and subsequent intravenous administration of milrinone on patients with symptomatic cerebral vasospasm. METHODS Seven patients with cerebral vasospasm were enrolled in this study. Milrinone was delivered intra-arterially via catheter at a rate of 0.25 mg/min. The total delivered dose was between 2.5 and 15 mg. Radiological measurement of the middle cerebral artery diameter and cerebral blood flow was carried out before and after arterial infusion. Intravenous treatment followed at 0.50 or 0.75 microg/kg/min for up to 2 weeks from the onset of subarachnoid hemorrhage. RESULTS Dilation of the vasospastic vessels occurred in all patients. The rate of cerebral blood flow was calculated in six patients and was increased in all. Subsequent intravenous infusion was effective in preventing a recurrence of symptomatic vasospasm in four of the seven patients. CONCLUSION It is suggested that milrinone was effective and safe for the treatment of cerebral vasospasm after subarachnoid hemorrhage in the patients in this series. Intra-arterial infusion with adjunctive intravenous infusion holds promise as a clinically advantageous treatment regimen.
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Arakawa Y, Yoshimura M, Kobayashi S, Ichihashi K, Miyao M, Momoi MY, Yanagisawa M. The use of intravenous immunoglobulin in Miller Fisher syndrome. Brain Dev 1993; 15:231-3. [PMID: 8214351 DOI: 10.1016/0387-7604(93)90071-f] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We report a patient with Miller Fisher syndrome who was treated with an intravenous high-dose of immunoglobulin. This syndrome is considered to be a benign variety of acute inflammatory demyelinating polyneuropathy (Guillain-Barré syndrome). However, there have been several reports of the need for ventilatory support and a few cases have had a fatal outcome. We observed a case of progressive Miller Fisher syndrome in a 3-year-old boy. Following 2 episodes of apnea lasting about 50 s each, he was treated with intravenous immunoglobulin (400 mg/kg/day) for 5 consecutive days. His respiratory state, general muscle strength, truncal ataxia and emotional state improved remarkably after this therapy.
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Ohsuka S, Ohta M, Masuda K, Arakawa Y, Kaneda T, Kato N. Lidocaine hydrochloride and acetylsalicylate kill bacteria by disrupting the bacterial membrane potential in different ways. Microbiol Immunol 1994; 38:429-34. [PMID: 7968672 DOI: 10.1111/j.1348-0421.1994.tb01803.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Lidocaine hydrochloride (LH), a local anesthetic, and acetylsalicylate (AcSAL), show antibacterial activity for both gram-negative and gram-positive bacteria. Kinetic studies indicated that antibacterial activity of LH was different from that of AcSAL. A subinhibitory concentration of LH and AcSAL enhanced the sensitivity of Escherichia coli, Salmonella typhimurium, and Pseudomonas aeruginosa to novobiocin and nalidixic acid. The synergistic effect of AcSAL with novobiocin and nalidixic acid was higher than that of LH. The effect of both drugs on the membrane potential of inner membrane was also studied using inverted membrane vesicles of bacteria. Both LH and AcSAL depolarized the membrane potential after the vesicles were energized with nicotinamide adenine dinucleotide. However, unlike AcSAL, pre-treatment of vesicles with LH had no effect on the generation of membrane potential. These results suggest that depolarization of the cytoplasmic membrane, preceded by the permeabilization of the outer membrane for gram-negative bacteria, is associated with antibacterial activity of LH and AcSAL. The difference in actions of LH and AcSAL was discussed.
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Nirei K, Kaneko M, Moriyama M, Arakawa Y. The clinical features of chronic hepatitis C are not affected by the coexistence of hepatitis B virus DNA in patients negative for hepatitis B surface antigen. Intervirology 2001; 43:95-101. [PMID: 10971127 DOI: 10.1159/000025030] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Hepatitis B virus (HBV) DNA has been detected in the sera of hepatitis patients who are negative for hepatitis B surface antigen (HBsAg) by polymerase chain reaction (PCR). The purpose of the present study was to clarify the clinical characteristics of patients with chronic hepatitis C who are negative for serum HBsAg and positive for HBV DNA. The subjects included 49 patients with chronic hepatitis C who were negative for serum HBsAg and 119 blood donors who served as healthy controls. Serum samples were tested for the presence of HBV DNA by the nested PCR method. Serum HBV DNA was detected in 18 (37.7%) of the 49 chronic hepatitis C patients and in none (0%) of the 119 blood donors. Among the hepatitis C patients, HBV DNA was detected in 20.7% of those who were negative for all HBV-associated markers and in 57.1% of those who were positive for one or more HBV-associated marker. The HBV DNA-positive rate among those in each F stage did not significantly differ. The liver function parameters of the HBV DNA-positive and the HBV DNA-negative chronic hepatitis C patients did not significantly differ. These results suggest that hepatitis C virus is frequently coinfected with serum HBsAg-negative HBV, and that the incidence of HBV infection in blood donors is low. However, it is considered that HBsAg-negative HBV infection does not modify the blood biochemical features of chronic hepatitis C.
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Aoki H, Kajino K, Arakawa Y, Hino O. Molecular cloning of a rat chromosome putative recombinogenic sequence homologous to the hepatitis B virus encapsidation signal. Proc Natl Acad Sci U S A 1996; 93:7300-4. [PMID: 8692987 PMCID: PMC38978 DOI: 10.1073/pnas.93.14.7300] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Previously, we reported that a 61-bp subgenomic HBV DNA sequence (designated as 15AB, nt 1855-1915) is a hot spot for genomic recombination and that a cellular protein binding to 15AB may be the putative recombinogenic protein. In the present study, we established the existence of a 15AB-like sequence in human and rat chromosomal DNA by Southern blot analysis. The 15AB-like sequence isolated from the rat chromosome demonstrated a 80.9% identity with 5'-CCAAGCTGTGCCTTGGGTGGC-3', at 1872-1892 of the hepatitis B virus genome, thought to be the essential region for recombination. Interestingly, this 15AB-like sequence also contained the pentanucleotide motifs GCTGG and CCAGC as an inverted repeat, part of the chi known hot spot for recombination in Escherichia coli. Importantly, a portion of the 15AB-like sequence is homologous (82.1%, 23/28 bp) to break point clusters of the human promyelocytic leukemia (PML) gene, characterized by a translocation [t(15;17)], and to rearranged mouse DNA for the immunoglobulin kappa light chain. Moreover, 15AB and 15AB-like sequences have striking homologies (12/15 = 80.0% and 13/15 = 86.7%, respectively) to the consensus sequence for topoisomerase II. Our present results suggest that this 15AB-like sequence in the rat genome might be a recombinogenic candidate triggering genomic instability in carcinogenesis.
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Nishinarita R, Niwano S, Niwano H, Nakamura H, Saito D, Sato T, Matsuura G, Arakawa Y, Kobayashi S, Shirakawa Y, Horiguchi A, Ishizue N, Igarashi T, Yoshizawa T, Oikawa J, Hara Y, Katsumura T, Kishihara J, Satoh A, Fukaya H, Sakagami H, Ako J. Canagliflozin Suppresses Atrial Remodeling in a Canine Atrial Fibrillation Model. J Am Heart Assoc 2021; 10:e017483. [PMID: 33399004 PMCID: PMC7955321 DOI: 10.1161/jaha.119.017483] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Background Recent clinical trials have demonstrated the possible pleiotropic effects of SGLT2 (sodium–glucose cotransporter 2) inhibitors in clinical cardiovascular diseases. Atrial electrical and structural remodeling is important as an atrial fibrillation (AF) substrate. Methods and Results The present study assessed the effect of canagliflozin (CAN), an SGLT2 inhibitor, on atrial remodeling in a canine AF model. The study included 12 beagle dogs, with 10 receiving continuous rapid atrial pacing and 2 acting as the nonpacing group. The 10 dogs that received continuous rapid atrial pacing for 3 weeks were subdivided as follows: pacing control group (n=5) and pacing+CAN (3 mg/kg per day) group (n=5). The atrial effective refractory period, conduction velocity, and AF inducibility were evaluated weekly through atrial epicardial wires. After the protocol, atrial tissues were sampled for histological examination. The degree of reactive oxygen species expression was evaluated by dihydroethidium staining. The atrial effective refractory period reduction was smaller (P=0.06) and the degree of conduction velocity decrease was smaller in the pacing+CAN group compared with the pacing control group (P=0.009). The AF inducibility gradually increased in the pacing control group, but such an increase was suppressed in the pacing+CAN group (P=0.011). The pacing control group exhibited interstitial fibrosis and enhanced oxidative stress, which were suppressed in the pacing+CAN group. Conclusions CAN and possibly other SGLT2 inhibitors might be useful for preventing AF and suppressing the promotion of atrial remodeling as an AF substrate.
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Shibayama K, Ohsuka S, Tanaka T, Arakawa Y, Ohta M. Conserved structural regions involved in the catalytic mechanism of Escherichia coli K-12 WaaO (RfaI). J Bacteriol 1998; 180:5313-8. [PMID: 9765561 PMCID: PMC107578 DOI: 10.1128/jb.180.20.5313-5318.1998] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Escherichia coli K-12 WaaO (formerly known as RfaI) is a nonprocessive alpha-1,3 glucosyltransferase, involved in the synthesis of the R core of lipopolysaccharide. By comparing the amino acid sequence of WaaO with those of 11 homologous alpha-glycosyltransferases, four strictly conserved regions, I, II, III, and IV, were identified. Since functionally related transferases are predicted to have a similar architecture in the catalytic sites, it is assumed that these four regions are directly involved in the formation of alpha-glycosidic linkage from alpha-linked nucleotide diphospho-sugar donor. Hydrophobic cluster analysis revealed a conserved domain at the N termini of these alpha-glycosyltransferases. This domain was similar to that previously reported for beta-glycosyltransferases. Thus, this domain is likely to be involved in the formation of beta-glycosidic linkage between the donor sugar and the enzyme at the first step of the reaction. Site-directed mutagenesis analysis of E. coli K-12 WaaO revealed four critical amino acid residues.
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Hashimoto N, Ichikawa D, Arakawa Y, Date K, Ueda S, Nakagawa Y, Horii A, Nakamura Y, Abe T, Inazawa J. Frequent deletions of material from chromosome arm 1p in oligodendroglial tumors revealed by double-target fluorescence in situ hybridization and microsatellite analysis. Genes Chromosomes Cancer 1995; 14:295-300. [PMID: 8605118 DOI: 10.1002/gcc.2870140408] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
We undertook a cytogenetic analysis of 29 human brain tumors using double-target fluorescence in situ hybridization (FISH) and focusing on chromosome arm 1p. One or more tumor suppressor genes in this arm have been suggested to be important in a variety of neuroectodermal tumors. The series included 9 oligodendrogliomas, 4 mixed gliomas, 10 astrocytomas, 4 glioblastomas, and 2 central neurocytomas. We hybridized pericentromeric (1q12) and subtelomeric (1p36) DNA probes to cell nuclei prepared from paraffin-embedded tissues and observed a strikingly high incidence of deletion of at least part of 1p in oligodendrogliomas (100%) and mixed gliomas (75%). The results of the FISH analyses were confirmed by demonstration of loss of heterozygosity for a microsatellite polymorphism in 10 of the 29 tumors. As well as supporting the feasibility of FISH for detecting allelic deletions in chromosomes from paraffin-embedded tumor samples, the alteration of 1p reported here will contribute to an understanding of the molecular genetic events in oligodendroglial tumor development.
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Arakawa Y, Sasaki Y, Igawa K, Tsuji H. Hydrogen bonding liquid crystalline benzoic acids with alkylthio groups: phase transition behavior and insights into the cybotactic nematic phase. NEW J CHEM 2017. [DOI: 10.1039/c7nj00282c] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel class of hydrogen bonding liquid crystalline benzoic acids with alkylthio groups was established and their phase transition behavior was investigated in detail.
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Ike Y, Arakawa Y, Ma X, Tatewaki K, Nagasawa M, Tomita H, Tanimoto K, Fujimoto S. Nationwide survey shows that methicillin-resistant Staphylococcus aureus strains heterogeneously and intermediately resistant to vancomycin are not disseminated throughout Japanese hospitals. J Clin Microbiol 2001; 39:4445-51. [PMID: 11724859 PMCID: PMC88563 DOI: 10.1128/jcm.39.12.4445-4451.2001] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A total of 6,625 methicillin-resistant Staphylococcus aureus (MRSA) clinical isolates obtained from 278 hospitals throughout Japan were obtained between November and December 1997 and were examined for their sensitivities to vancomycin using Mueller Hinton (MH), brain heart infusion (BHI), agar plates, or the broth microdilution method. A concentrated inoculum of an MRSA strain or the use of highly enriched medium, such as BHI medium, allows an individual cell to grow on agar plates containing a vancomycin concentration greater than the MIC for the parent strain. However, cells of the colonies which grew on BHI agar plates containing the higher vancomycin concentrations did not acquire a level of vancomycin resistance greater than that of the parent strain and were not subpopulations of heterogeneously vancomycin-resistant MRSA. There was no significance in the fact that these colonies grew on the higher concentration of vancomycin: none showed stable resistance to vancomycin at a concentration above the MIC for the parent strain, and no cell from these colonies showed a relationship between the MIC and the ability of these colonies to grow on higher concentrations of vancomycin. The vancomycin MIC was not above 2 microg/ml for any of the cells originating from these colonies. No Mu3-type heterogeneously resistant MRSA strains, which constitutively produce subpopulations from MRSA clinical isolates with intermediate vancomycin resistance at a high frequency, were detected. There was a unipolar distribution of the MICs ranging from 0.25 to 2 microg of vancomycin/ml among the 6,625 MRSA clinical isolates, indicating that there was no Mu50-type intermediately vancomycin-resistant MRSA (MIC, 8 microg/ml by National Committee for Clinical Laboratory Standards criteria) among the clinical isolates, and there was no evidence of dissemination of Mu3-type MRSA heteroresistant to vancomycin.
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Katoh-Semba R, Semba R, Kato H, Ueno M, Arakawa Y, Kato K. Regulation by androgen of levels of the beta subunit of nerve growth factor and its mRNA in selected regions of the mouse brain. J Neurochem 1994; 62:2141-7. [PMID: 8189222 DOI: 10.1046/j.1471-4159.1994.62062141.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Our previous studies showed that the concentration of the beta subunit of nerve growth factor (beta-NGF) in nervous tissues is higher in male than in female mice. To identify the brain regions that are affected by androgens, the amounts of beta-NGF protein and its mRNAs were measured in male, female, and castrated male CD-1 mice and testicular feminization mice at 3-4 months of age. Among tissues examined, the hypophysis of males contained the highest average concentration of beta-NGF protein. In most regions of the brain, individual levels were more variable in males than in females. However, after the castration, such variations in beta-NGF levels disappeared. Average levels of beta-NGF protein in males were higher in the cerebellum (eightfold higher), olfactory bulb (12-fold higher), hypothalamus (sixfold higher), and hypophysis (72-fold higher) than those in corresponding regions of females. No significant differences were observed in levels of beta-NGF protein in the hippocampus, cerebral cortex, striatum, septum, and brainstem. The castration of male mice caused a reduction in levels of beta-NGF protein in the hypothalamus and hypophysis, but not in the cerebellum and olfactory bulb, to the female levels. The concentrations of beta-NGF protein in testicular feminization mice were similar to those in female CD-1 mice in all regions.(ABSTRACT TRUNCATED AT 250 WORDS)
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Sato K, Shidahara M, Watabe H, Watanuki S, Ishikawa Y, Arakawa Y, Nai YH, Furumoto S, Tashiro M, Shoji T, Yanai K, Gonda K. Performance evaluation of the small-animal PET scanner ClairvivoPET using NEMA NU 4-2008 Standards. Phys Med Biol 2015; 61:696-711. [PMID: 26716872 DOI: 10.1088/0031-9155/61/2/696] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The aim of this study was to evaluate the performance of ClairvivoPET using NEMA NU4 standards. The ClairvivoPET incorporates a LYSO dual depth-of-interaction detector system with 151 mm axial field of view (FOV). Spatial resolution, sensitivity, counting rate capabilities, and image quality were evaluated using NEMA NU4-2008 standards. Normal mouse imaging was also performed for 10 min after intravenous injection of (18)F(-)-NaF. Data were compared with 19 other preclinical PET scanners. Spatial resolution measured using full width at half maximum on FBP-ramp reconstructed images was 2.16 mm at radial offset 5 mm of the axial centre FOV. The maximum absolute sensitivity for a point source at the FOV centre was 8.72%. Peak noise equivalent counting rate (NECR) was 415 kcps at 14.6 MBq ml(-1). The uniformity with the image-quality phantom was 4.62%. Spillover ratios in the images of air and water filled chambers were 0.19 and 0.06, respectively. Our results were comparable with the 19 other preclinical PET scanners based on NEMA NU4 standards, with excellent sensitivity because of the large FOV. The ClairvivoPET with iterative reconstruction algorithm also provided sufficient visualization of the mouse spine. The high sensitivity and resolution of the ClairvivoPET scanner provided high quality images for preclinical studies.
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Research Support, Non-U.S. Gov't |
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Hayakawa S, Nakajima N, Karasaki-Suzuki M, Yoshinaga H, Arakawa Y, Satoh K, Yamamoto T. Frequent presence of Helicobacter pylori genome in the saliva of patients with hyperemesis gravidarum. Am J Perinatol 2001; 17:243-7. [PMID: 11110341 DOI: 10.1055/s-2000-10005] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Recently, possible involvement of Helicobacter pylori (H. pylori) in hyperemesis gravidarum have been reported based on serological studies and the therapeutic effects of antibiotics. In this study, we examined for the presence of H. pylori genome [by (PCR) of saliva] in combination with serological techniques. Thirty-four patients with hyperemesis and 29 normal pregnant subjects were examined for serum anti-H. pylori IgG antibodies and PCR of saliva. By serum antibody test, 16 of 34 hyperemesis patients (47.5%) were positive for anti-H. pylori IgG antibody, while 6 of 29 control subjects (20.6%) were positive (chi2 p < 0.0005). PCR revealed positive H. pylori genome in 21 cases out of 34 hyperemesis (61.8%, 14 of 16 patients positive for H. pylori antibody and 7 of H. pylori-antibody-negative 18 patients) and 8 of 29 control subjects (27.6%) (chi2 p < 0.000001). We suggest chronic infection of H. pylori as one of the important factors on the pathogenesis of hyperemesis gravidarum even though it may not be the single cause of the disorder.
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Arakawa Y, Nakajima S, Kang S, Shigeta M, Konishi GI, Watanabe J. Design of an extremely high birefringence nematic liquid crystal based on a dinaphthyl-diacetylene mesogen. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm32448b] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Abstract
Organotin compounds such as Bu2SnCl2, Bu3SnCl and Ph3SnCl suppressed significantly not only chemotactic response of neutrophils to stimulation by the chemoattractant fMet-Leu-Phe but also phospholipase activity in situ as measured by the release of [1-14C] arachidonic acid previously incorporated into phospholipids. Moreover, these suppressions were dose dependent and a parallelism was found between dose-dependent inhibition of chemotaxis and that of arachidonate release. These results suggest that the chemotactic response is controlled by the activation of phospholipase activity in neutrophils, and that the inhibitory effects of these organotin compounds on chemotactic response reflect the blockage of phospholipase activation system regulated by phosphorylation of lipomodulin.
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Arakawa Y, Takahashi Y, Sebata M. The effect of acid etching on the cervical region of the buccal surface of the human premolar, with special reference to direct bonding techniques. AMERICAN JOURNAL OF ORTHODONTICS 1979; 76:201-8. [PMID: 382862 DOI: 10.1016/0002-9416(79)90121-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Etching action on the cervical enamel compared to the central and incisal enamel of the buccal surfaces of premolars was investigated by using the scanning electron and optical microscopes. In SEM observations, the etched cervical enamel surface showed a pitted feature with no prism delineation, regardless of the prolonged etching time and the removal of enamel surface. The etched central and incisal enamel surface showed the characteristic prism-end structure. In optical microscopic observations, the tags formed at the cervical region were shorter and less numerous than those formed at the central and incisal enamel surfaces.
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Kirikae T, Mizuguchi Y, Arakawa Y. Investigation of isolation rates of Pseudomonas aeruginosa with and without multidrug resistance in medical facilities and clinical laboratories in Japan. J Antimicrob Chemother 2008; 61:612-5. [DOI: 10.1093/jac/dkm537] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Arakawa Y, Tachibana S. A direct and sensitive determination of histamine in acid-deproteinized biological samples by high-performance liquid chromatography. Anal Biochem 1986; 158:20-7. [PMID: 2432802 DOI: 10.1016/0003-2697(86)90582-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A convenient method for the routine measurement of histamine (HA) in biological samples was developed. This method does not require any preliminary purification or concentration of HA, and features high sensitivity, specificity, and reliability. The method consists of the direct application of the acid-deproteinized sample to high-performance liquid chromatography on a sulfonated polystyrene column with detection by means of a postcolumn fluorogenic reaction with o-phthaladehyde. The detection limit was found to be 0.1 pmol (signal-to-noise ratio = 3). The coefficient of variation for measurements of 10 pmol of standard histamine was 1.1%. Each chromatography takes only 10 min and therefore more than 50 samples can be measured in a day. The high sensitivity of the method allows it to be applied even to samples of very low HA concentration such as human plasma without any procedure for concentration of the sample, and further, only 0.1 ml of the sample is necessary for determination. The method was applied to compare the HA levels of the whole blood and plasma of man and various animals. Applications of the method to the supernatant of rat peritoneal mast cell incubates and to extracts of mouse brain and stomach are also described.
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Shiratori Y, Kato N, Yokosuka O, Hashimoto E, Hayashi N, Nakamura A, Asada M, Kuroda H, Ohkubo H, Arakawa Y, Iwama A, Omata M. Quantitative assays for hepatitis C virus in serum as predictors of the long-term response to interferon. J Hepatol 1997; 27:437-44. [PMID: 9314119 DOI: 10.1016/s0168-8278(97)80346-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND/AIMS Interferon therapy has a beneficial effect in patients with chronic hepatitis C who have a low viral load. The aim of this study was to compare the core protein level with HCV RNA levels and to analyze whether virus quantitation predicts the efficacy of interferon therapy. METHODS HCV core protein level assessed by the recently developed assay was compared with HCV RNA levels measured by three different methods (Amplicor-HCV monitor, competitive RT(CRT)-PCR, and bDNA probe assay) in 352 patients with chronic hepatitis C in relation to viral serotype. RESULTS From 91% (320/352) to 93% (299/322) of patients with viremia were detected by Amplicor-monitor and CRT-PCR, in contrast to 60% (187/312) and 74% (191/258) by bDNA and HCV core protein assay, respectively. The HCV core protein level was positively correlated with HCV RNA levels measured by the three assays (r = 0.680 to 0.731). Serum HCV RNA and core protein levels were significantly lower in patients with serotype 2 than in those with serotype 1. Viral eradication after interferon therapy was observed in 60-70% of the patients with < 1 x 10(4) copies/ml of HCV RNA by Amplicor-monitor assay, < 2 x 10(5) copies/ml by CRT-PCR, < 0.5 Meq/ml by bDNA assay, and < 20 pg/ml of core protein by HCV core protein assay. Viral eradication was uncommon (< 11%) among the patients with higher viral loads. Bivariate analysis revealed that the outcome of interferon therapy was more closely associated with both HCV core protein and RNA levels than the HCV serotype. CONCLUSIONS Quantitation of HCV core protein and HCV RNA in useful for prediction of the interferon response.
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