Biofilm formation among methicillin-resistant Staphylococcus aureus isolates from patients with urinary tract infection.

Staphylococci have been confirmed to form biofilms on various biomaterials. The purpose of this study was to investigate biofilm formation among methicillin-resistant Staphylococcus aureus (MRSA) isolates from patients with urinary tract infection (UTI) and to assess the relationship between biofilm-forming capacities and virulence determinants/clinical background. Over a 12-year period from 1990 through 2001, a total of 109 MRSA isolates were collected from patients (one isolate per patient) with UTI at the urology ward of Okayama University Hospital. We used the in vitro microtiter plate assay to quantify biofilm formation. We then investigated the presence of several virulence determinants by polymerase chain reaction assay and found eight determinants (tst, sec, hla, hlb, fnbA, clfA, icaA, and agrII) to be predominant among these isolates. Enhanced biofilm formation was confirmed in hla-, hlb-, and fnbA-positive MRSA isolates, both individually and in combination. Upon review of the associated medical records, we concluded that the biofilm-forming capacities of MRSA isolates from catheter-related cases were significantly greater than those from catheter-unrelated cases. The percentage of hla-, hlb-, and fnbA-positive isolates was higher among MRSA isolates from catheter-related cases than those from catheter-unrelated cases. Our studies suggest that MRSA colonization and infection of the urinary tract may be promoted by hla, hlb, and fnbA gene products.</p

Detection of the Viruses Occurring in Oriental Cymbidium in Japan

A survey of virus diseases occurring in Oriental Cymbidium collected from a commerical nursery and home garden in Japan was conducted in 1991-1994. Identification of the vurus was based on partcle morphology, symptomatology in indicator plants, ultrastructure of infected cells and serology. Four viruses, odontoglossum ringspot tabamovirus(ORSV), cymbidium mosaic potexvirus(CyMV), orchid fleck virus (ORV) and a previously underscribed spherical virus, were found in 27 out of 37 Cymbidium plants tested. ORSV was detected from 11 plants belinging to Cym. ensifolium, Cym. forrestii, Cym. goeringii, Cym. kanran, Cym. sinense and Cymbidium spp. showing chlorotic streaks and/or mild mosaic. CyMV was isolated from only one plant of Cymbidium sp. showing mosaic and necrotic spots on leaves. In negatibvely stained dip preparations from plants infected with ORSV and CyMV, rod shaped particles of ca. 310 nm and flexuous rod-shaped ca. 475 nm in length were observed, respectively. The viruses were reacted strongly with respective antiserum to each virus in immunosorbent electron microcopy and inderect ELISA. OFV was isolated from four plants of Cym. formosanum, Cym. kanran, Cym. sinense and Cymbidium sp. showing mosaic and necrotic flecks. The virus had non-enveloped, bullet-shaped particles about 40×120～150 nm in dip preparation. The undescribed spherical virus, ca. 28 nm diameter, was isolated from 11 plants of Cym. forrestii, Cym. goeringii and Cymbidium spp. showing stunting and chlorotic streaks on newly developed leaves. The virus was mechanically transmitted only to Cymbidium orchids. Previously, we designated it as cymbidium chlorotic mosaic sobemovirus(CyCMV)(Kondo et al,1994),as the virus was considered to be a new member of the genus Sobemovirsu.1991～1994年にかけ山口県ならびに岡山県下を中心に東洋ラン（シンビジウム属）のウイルス病の発生調査を行った。ウイルス病様の症状を示していた37株の東洋ランを採集し、これらから病原ウイルスの分離、同定を試みた結果、オドントグロッサムリングスポットウイルス（ORSV）、シンビジウムモザイクウイルス（CyMV）、ランえそ斑紋ウイルス（OFV）ならびにソベモウイルス属の新ウイルスであるシュンラン退緑ウイルス（CyCMV）の発生が認められた。ORSVは退緑条斑や軽いモザイク症状を示すスルガラン、カンラン、コラン、ホウサイランなどから分離された。CyMVは明瞭なえそ斑を伴うモザイクを呈した東洋ラン（品種不祥、赤芽素心）から分離された。ORSVならびにCyMVに感染した植物のDN法試料中には電顕観察でそれぞれ長さ約310nmの棒状粒子と約475nmのひも状粒子が観察され、免疫電顕法と間接ELISA法では、これらのウイルスはそれぞれのウイルスに対する抗血清とよく反応した。OFVは退緑斑あるいはえそ斑点を生じているイトラン、カンラン、ホウサイランなどから検出された。その粒子形態は長さ約120～150nm、幅約40nmの被膜のない弾丸状あるいは桿菌状であった。CyCMVは新芽に明瞭な退緑斑や退緑状斑症状を示すシナシュンラン、シュンランなどから分離された。この球状ウイルスは直径約28nmで、シンビジウム属以外の植物には感染が認められなかった。今回の発生調査では、東洋ランからはORSVならびに新ウイルスのCyCMVがもっとも多く分離され、OFVは4株から、CyMVは1株から検出された。またこれらのウイルスによる重複感染は認められなかった

Clinical implications of biofilm formation by Enterococcus faecalis in the urinary tract.

The potential relationships between biofilm formation and pathogenicity of Enterococcus faecalis in urinary tract infections (UTI) were investigated. Over a 12-year period from 1991 through 2002, a total of 352 E.faecalis isolates were collected from patients with complicated UTI (one isolate per patient) at the urology ward of Okayama University Hospital. We analyzed the prevalence and transferability of genes encoding virulence factors(asa1, esp, cylA, gelE /sprE )and antimicrobial resistance(aac(6') /aph(2'')). The production of biofilm, hemolysin and gelatinase by these isolates was also examined and the associated medical records of patients were retrospectively reviewed. Of 352 E. faecalis isolates, 315 possessed and/or genes. Of the 63 hemolysin- and 167 gelatinase-producing isolates, 59 and 94 isolates, respectively, possessed both asa1 and esp genes. E. faecalis isolates with both asa1 and esp genes formed biofilms at significantly higher rates than those with neither gene (P=0.038). The genes encoding asa1, cylA , and aac(6') /(aph(2'') were transferable and appeared to have accumulated in these isolates. The E. faecalis isolates possessing asa1 and/or esp genes were found from both catheter-related or -unrelated UTI. Our study indicates that E. faecalis isolates that have accumulated virulence genes are apt to form persistent biofilms in the urinary tracts.</p

A new adrenal computer imaging technique using dual-radioisotopes.

Computer processed adrenal imaging using dual-radioisotopes, 6 beta-iodomethyl-19-nor-cholest-5(10)-en-3 beta-ol-131I and 99mTc-phytate was performed in 12 patients with primary aldosteronism and 4 with Cushing's syndrome due to adrenocortical tumor. Adreno-photoscanning and hepato-photoscanning were performed in the same position 2-4 days following intravenous administration of radiocholesterol. The scintigraphic information was stored on cassettes and scan subtraction and a digital-computer method for data smoothing were performed on an oscilloscope. The tumor site could be determined in all cases until day 4 by this computer processed image.</p

Close Relationship between Serotype and Pathogenicity of Cucumber Mosaic Virus

Sixty-eight isolates of cucumber mosaic virus (CMV) belonging to the Y serotype (serogroup) or P serotype (serotype Ⅱ)　in Japan were inoculated to Nicotiana tabacum cv. White Burley and the symptoms were observed up to three months after inoculation. These isolates were divided into four goups accoding to symptomatology on tabacco plant. None of the isoletes obtained from lilies infected tobacco plants systemically. The plants inoculated with isolates of the P serotype showed systemic mosaic, but only occasional mild symptoms were observed on newly developed leaves. On the other hand, all isolates of Y serotype showed symptoms consisting of mosaic, distortion and/or necrosis throughout the experimental period. In another experiment, reactions of some selected test plants to 30 isolates belonging to the Y or P serotype were examined. Lily isolates may be unique strain of CMV as they did not cause systemic infections on Lycopersicon esculentum, Solanum melongena or Cucumis sativus. Host range tests using 16 isolates originally obtained from plants other than lilies demonstrated a close relationship between serotype and pathogenicity to some test plants including N.tabacum, N. clevelandii, L.esculentum, Pisum sativum, phaseolus angularis and Zea mays.日本で分離されたキュウリモザイクウイルス（CMV）のY血清型あるいはP血清型に属する68分離株をタバコに汁液接種した結果、それらは病徴から4つのタイプに類別することができた。それらのうち、ユリからの14分離株はタバコには全身感染しなかった。タバコに全身感染する分離株のうち、Y血清型のすべての分離株は接種後長期間経過しても、新葉にモザイク、えそ、奇形などの病徴が常に認められたが、P型では接種後の日数が経過すると新しく展開した葉には病徴が認められないことが多かった。また、CMVのそれぞれの血清型の分離株を各種植物に接種し、宿主範囲および病徴を調べた結果、ユリからの分離株はタバコ、トマトなどのナス科植物やキュウリなどに全身感染しない点で、これまでに報告されている多くの系統とは異なっていた。また、ユリ以外の植物から得られた分離株では、数種のナス科植物、エンドウ、アズキ、トウモロコシなどにおいて、血清型と病原性との間に明確な関連が認められた