Identification of a novel zinc metalloprotease through a global analysis of clostridium difficile extracellular proteins

Clostridium difficile is a major cause of infectious diarrhea worldwide. Although the cell surface proteins are recognized to be important in clostridial pathogenesis, biological functions of only a few are known. Also, apart from the toxins, proteins exported by C. difficile into the extracellular milieu have been poorly studied. In order to identify novel extracellular factors of C. difficile, we analyzed bacterial culture supernatants prepared from clinical isolates, 630 and R20291, using liquid chromatography-tandem mass spectrometry. The majority of the proteins identified were non-canonical extracellular proteins. These could be largely classified into proteins associated to the cell wall (including CWPs and extracellular hydrolases), transporters and flagellar proteins. Seven unknown hypothetical proteins were also identified. One of these proteins, CD630_28300, shared sequence similarity with the anthrax lethal factor, a known zinc metallopeptidase. We demonstrated that CD630_28300 (named Zmp1) binds zinc and is able to cleave fibronectin and fibrinogen in vitro in a zinc-dependent manner. Using site-directed mutagenesis, we identified residues important in zinc binding and enzymatic activity. Furthermore, we demonstrated that Zmp1 destabilizes the fibronectin network produced by human fibroblasts. Thus, by analyzing the exoproteome of C. difficile, we identified a novel extracellular metalloprotease that may be important in key steps of clostridial pathogenesis

Upper limits from the LIGO and TAMA detectors on the rate of gravitational-wave bursts

We report on the first joint search for gravitational waves by the TAMA and LIGO collaborations. We looked for millisecond-duration unmodelled gravitational-wave bursts in 473 hr of coincident data collected during early 2003. No candidate signals were found. We set an upper limit of 0.12 events per day on the rate of detectable gravitational-wave bursts, at 90% confidence level. From simulations, we estimate that our detector network was sensitive to bursts with root-sum-square strain amplitude above approximately 1-3×10 in the frequency band 700-2000 Hz. We describe the details of this collaborative search, with particular emphasis on its advantages and disadvantages compared to searches by LIGO and TAMA separately using the same data. Benefits include a lower background and longer observation time, at some cost in sensitivity and bandwidth. We also demonstrate techniques for performing coincidence searches with a heterogeneous network of detectors with different noise spectra and orientations. These techniques include using coordinated signal injections to estimate the network sensitivity, and tuning the analysis to maximize the sensitivity and the livetime, subject to constraints on the background

Papilloma and sebaceous gland hyperplasia of the lacrimal caruncle: a case report

Maria Miura-Karasawa,1 Hiroshi Toshida,1 Toshihiko Ohta,1 Akira Murakami2 1Department of Ophthalmology, Juntendo University Shizuoka Hospital, Izunokuni, Shizuoka, Japan; 2Department of Ophthalmology, Juntendo University School of Medicine, Tokyo, Japan Objective: To report a case of coincidence of sebaceous gland hyperplasia and papilloma with detection of human papillomavirus-51 in the apical portion by in situ hybridization.Case presentation: A 75-year-old man noted discomfort at the inner canthus of his left eye when he blinked. A tumor of the lacrimal caruncle was identified and resected. The base of the tumor had a smooth surface and was whitish. In addition, a “navel-like structure” was seen, and the findings strongly suggested sebaceous gland hyperplasia of the lacrimal caruncle. The apical portion of the tumor was a papillomatous lesion. Histological examination of the resected tumor led to a diagnosis of sebaceous gland hyperplasia. Human papillomavirus-51 was detected in the apical portion by in situ hybridization. Based on these results, the final diagnosis was sebaceous gland hyperplasia with papilloma. No recurrence of either tumor has been observed up to 3 years postoperatively.Conclusion: This might be the first report of a case of coincidence of sebaceous gland hyperplasia and papilloma, even though the association between these two lesions was unclear, including which developed first. Keywords: lacrimal caruncle, sebaceous gland hyperplasia, papilloma, human papilloma virus, HPV-5

Endoscopic and clinical evaluation of treatment and prognosis of Cronkhite–Canada syndrome: a Japanese nationwide survey

BACKGROUND: First reported in 1955, Cronkhite–Canada syndrome (CCS), a rare syndrome characterized by ectodermal abnormalities and inflammatory changes of the gastrointestinal tract mucosa, has been associated with a poor prognosis and life-threatening malignant complications. In a large population survey, we endeavored to characterize the course and treatment outcome of CCS through clinical and endoscopic assessment, and to explore its optimal treatment and surveillance strategy. METHODS: A retrospective analysis of 210 patients with CCS was conducted via a questionnaire-based nationwide survey of 983 teaching hospitals located throughout Japan. We assessed clinical features, endoscopic findings, treatments used, and short- and long-term outcomes. RESULTS: The average age at diagnosis was 63.5 years. In all cases, upper or lower gastrointestinal tract polyposis was confirmed, accompanied by characteristic ectodermal abnormalities. Of the treatments used, oral corticosteroids (30–49 mg/day) were the most effective treatment for active disease, with adjunctive nutritional support considered beneficial. With corticosteroid treatment, abdominal symptoms were relieved within a few months, whereas polyp regression often required more than 6 months. Maintenance of endoscopic remission with or without steroids for 3 years significantly lowered the development of CCS-related cancer, compared with relapsers or nonresponders, underscoring the importance of sustained endoscopic remission for cancer prevention. CONCLUSIONS: The prognosis of CCS has greatly improved through the use of improved medical treatment. Although CCS continues to be relentlessly progressive, carrying a high cancer risk, a sufficient dose and duration of corticosteroid therapy accompanied by nutritional support and periodic endoscopic surveillance appears to improve its natural history. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00535-015-1107-7) contains supplementary material, which is available to authorized users