A novel bacterium that infects laboratory rats was isolated from wild Rattus norvegicus rats in Japan. Transmission electron microscopy of the spleen tissue revealed small cocci surrounded by an inner membrane and a thin, rippled outer membrane in a membrane-bound inclusion within the cytoplasm of endothelial cells. Phylogenetic analysis of the 16S rRNA gene sequence of the bacterium found in R. norvegicus rats and Ixodes ovatus ticks in Japan revealed that the organism represents a novel clade in the family Anaplasmataceae, which includes the Schotti variant found in Ixodes ricinus ticks in the Netherlands and the Ehrlichia-like Rattus strain found in R. norvegicus rats from China. The novel clade was confirmed by phylogenetic analysis of groESL sequences found in R. norvegicus rats and Ixodes ovatus ticks in Japan. No serological cross-reactivity was detected between this bacterium and members of the genera Anaplasma, Ehrlichia or Neorickettsia in the family Anaplasmataceae. It is proposed that this new cluster of bacteria should be designated 'Candidatus Neoehrlichia mikurensis'.The family Anaplasmataceae currently includes five genera: Ehrlichia, Anaplasma, Neorickettsia, Aegyptianella and Wolbachia (Dumler et al., 2001;Rikihisa et al., 2003). These are all obligately intracellular bacteria that are capable of infecting invertebrates and/or vertebrates. Species of the genera Ehrlichia and Anaplasma include the emerging tick-borne human pathogens, such as Ehrlichia chaffeensis and Anaplasma phagocytophilum. As it is difficult to isolate and culture this group of bacteria, the ultrastructure and sequences of conserved genes, such as 16S rRNA, groEL and gltA (citrate synthase gene), are primarily used to identify and classify this group of bacteria. The present study describes a novel bacterium in the family Anaplasmataceae that was isolated from wild Rattus norvegicus rats by using laboratory rats. The bacteria were found in R. norvegicus rats and Ixodes ovatus ticks in Japan and represent a novel genetic cluster, based on phylogenetic analysis of 16S rRNA gene sequences that included the bacteria found in R. norvegicus rats in China (Pan et al., 2003) and in Ixodes ricinus ticks in the Netherlands (Schouls et al., 1999). Of note, infection of I. ricinus ticks with similar bacteria in Baltic regions of Russia was reported by Alekseev et al. (2001). A similar 16S

Wild deer are one of the important natural reservoir hosts of several species of Ehrlichia and Anaplasma that cause human ehrlichiosis or anaplasmosis in the United States and Europe. The primary aim of the present study was to determine whether and what species of Ehrlichia and Anaplasma naturally infect deer in Japan. Blood samples obtained from wild deer on two major Japanese islands, Hokkaido and Honshu, were tested for the presence of Ehrlichia and Anaplasma by PCR assays and sequencing of the 16S rRNA genes, major outer membrane protein p44 genes, and groESL. DNA representing four species and two genera of Ehrlichia and Anaplasma was identified in 33 of 126 wild deer (26%). DNA sequence analysis revealed novel strains of Anaplasma phagocytophilum, a novel Ehrlichia sp., Anaplasma centrale, and Anaplasma bovis in the blood samples from deer. None of these have been found previously in deer. The new Ehrlichia sp., A. bovis, and A. centrale were also detected in Hemaphysalis longicornis ticks from Honshu Island. These results suggest that enzootic cycles of Ehrlichia and Anaplasma species distinct from those found in the United States or Europe have been established in wild deer and ticks in Japan.

The lack of consistent definitions and nomenclature across clinical trials of novel devices, drugs, or biologics poses a significant barrier to accrual of knowledge in and across peripheral artery disease therapies and technologies. Recognizing this problem, the Peripheral Academic Research Consortium, together with the U.S. Food and Drug Administration and the Japanese Pharmaceuticals and Medical Devices Agency, has developed a series of pragmatic consensus definitions for patients being treated for peripheral artery disease affecting the lower extremities. These consensus definitions include the clinical presentation, anatomic depiction, interventional outcomes, surrogate imaging and physiological follow-up, and clinical outcomes of patients with lower-extremity peripheral artery disease. Consistent application of these definitions in clinical trials evaluating novel revascularization technologies should result in more efficient regulatory evaluation and best practice guidelines to inform clinical decisions in patients with lower extremity peripheral artery disease.

Features of tumefactive demyelinating lesion (TDL) on magnetic resonance imaging (MRI)can facilitate the differential diagnosis of TDL and neoplastic lesions, but vary considerably among patients. The larger TDL grows, the more difficult it becomes to differentiate TDL from neoplastic lesions. The purpose of this study was to elucidate typical MRI features in 12 patients with large TDL (>30 mm in diameter). METHODSWe identified 12 patients with large TDL (six men, six women; age range 17-64 years, median age 27 years) and studied the clinical histories and the results of laboratory and various radiological studies in these patients. All cases of clinically definite multiple sclerosis were diagnosed in accordance with McDonald's revised criteria. RESULTS Common MRI features of large TDLs included variable degrees of mass effect (71%) and edema (100%), a T2 hypointense rim (79%), venular enhancement (57%), and peripheral restriction on diffusion-weighted images (50%). Ring enhancement (38%), open-ring enhancement (31%), or decreased N-acetylaspartate ratios on magnetic resonance spectroscopy (22%) were less frequently observed. Brain angiography demonstrated venous dilatations on and around the TDL. CONCLUSIONSThe diagnosis of large TDL is challenging. Our findings suggest that multiple venous dilatations on and around TDLs on angiography can facilitate diagnosis.

The 16s rRNA gene of a new infectious agent, strain AS145T (T = type strain), which was isolated from a wild mouse in Japan, was amplified by using the PCR. The amplimers were directly sequenced by dideoqnucleotide methods with Tuq DNA polymerase. Sequence comparisons with other members of the tribe Ehrlichieue and related species revealed that the infectious agent isolated from the mouse is a new species of the genus Ehrlichiu that is most closely related to Ehrlichiu chaffeensis (level of sequence similarity, 97.9%), an agent of human ehrlichiosis in the United States. This result was consistent with the results of an immunoblot analysis performed with immune sera against different ehrlichiosis agents. On the basis of these findings and other morphological, biological, and serological characteristics of the organism, we propose that ehrlichiae with these properties belong to a new species, Ehrlichiu muris.According to Beigey ' s Manual of Systematic Bacteriology (loa), the genus Ehrlichia includes four species that are the etiological agents of ehrlichiosis in dogs, horses, ruminants, and humans. Recently, several additional Ehrlichia species have been isolated and/or identified la, 7 . In 1983, an infecisolated from the spleen of a wild mouse (Eothenomys kageus) in Japan (5). This organism was identified as a member of the genus Ehrlichia on the basis of the results of morphological and antigenic comparisons (5). Like members of other Ehrlichia spp., strain AS145T is a small, gram-negative, pleomorphic, obligately intracellular bacterium (5). In laboratory mice, strain AS145T causes severe clinical signs similar to those caused by Ehrlichia sennetsu or Ehrlichia risticii, including splenomegaly and lymphadenopathy (5). However, using serological cross-reactivity as determined by the indirect fluorescent-antibody (IFA) test and Western blot (immunoblot) analysis, Kawahara et al. found that strain AS145T is more closely related to Ehrlichia canis (5). In addition, strain AS145T forms tightly packed morulae in host cells, like E. canis does (5).So far, strain AS145T is the only ehrlichial strain that has been isolated from mice. In order to define the phylogenetic relationship between this organism and other ehrlichial species, the 16s rRNA gene of strain AS145T was amplified by PCR and sequenced. In this paper we describe the results of a comparison of 16s rRNA sequences, a Western blot analysis, and tests to determine the susceptibility of dogs to strain AS145T. On the basis of our results, we propose that strain AS145T should be considered a member of a new Ehrlichia species which is most closely related to Ehrlichia chaffeensis, a human ehrlichiosis agent, and somewhat less closely related to Ehrlichia ewingii and E. canis. MATERIALS AND METHODSEhrlichiu spp. and cell culture. Strain AS145T, E. chaffeensis, and E. canis were cultured in dog macrophage cell line DH82 in minimum essential medium (GIBCO, Grand Island, N.Y.) containing 10% fetal bovine serum and 2 mM L-glutamine in a 5% CO,-air atmosphere (10)....