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Isolation, cultivation, and characterization of the intestinal microorganisms are important for understanding the comprehensive physiology of the human gastrointestinal (GI) tract microbiota. Here, we isolated two novel bacterial strains, YIT 12067 T and YIT 12068, from the feces of healthy human adults. Phylogenetic analysis indicated that they belonged to the same species and were most closely related to Phascolarctobacterium faecium ACM 3679 T , with 91.4% to 91.5% 16S rRNA gene sequence similarities, respectively. Substrate availability tests revealed that the isolates used only succinate; they did not ferment any other short-chain fatty acids or carbohydrates tested. When these strains were cocultured with the xylan-utilizing and succinate-producing bacterium Paraprevotella xylaniphila YIT 11841 T , in medium supplemented with xylan but not succinate, their cell numbers became 2 to 3 orders of magnitude higher than those of the monoculture; succinate became undetectable, and propionate was formed. Database analysis revealed that over 200 uncultured bacterial clones from the feces of humans and other mammals showed high sequence identity (>98.7%) to YIT 12067 T . Real-time PCR analysis also revealed that YIT 12067 T -like bacteria were present in 21% of human fecal samples, at an average level of 3.34 × 10 8 cells/g feces. These results indicate that YIT 12067 T -like bacteria are distributed broadly in the GI tract as subdominant members that may adapt to the intestinal environment by specializing to utilize the succinate generated by other bacterial species. The phylogenetic and physiological properties of YIT 12067 T and YIT 12068 suggest that these strains represent a novel species, which we have designated Phascolarctobacterium succinatutens sp. nov.

In this paper, we propose a velocity control method for leg/wheel type robots by using tire side slip angle and tire slip ratio. Side slip angle and slip ratio is measured by caster type odometers which are comprised of directional sensors and travel distance sensors. The odometer system has redundant four encoders to measure three dimensional velocities: planar two dimensional and rotational movements. We reduce the error between target velocity and actual velocity by feedback control based on both tire slip angle and slip ratio. This method can improve stability and accuracy of movement of vehicles. The experimental vehicle is an omnidirectional vehicle which has legs comprised of three joints. Experimental results of circular trajectory running show effectiveness of the proposed control method.

Highly pathogenic avian influenza A virus subtype H5N1 can potentially generate novel variants during replication of infected hosts. To determine which H5N1 variants predominate in wild birds, we determined the sequences of RT-PCR amplified viral genes from several organs of infected chickens and ducks from Egypt, where H5N1 outbreaks in birds are endemic. Comparison of the sequences in viruses from trachea, lung, brain and liver revealed diversification with different amino acid substitutions in different ducks, but no diversification in chickens. These specific amino acid substitutions were rare among viruses currently circulating in Egypt. In addition, the H5N1 variants showed distinct growth kinetics in duck, canine and human cells. Our findings suggested that ducks can generate H5N1 variants with novel amino acid substitutions that might serve as aetiological agents for new influenza virus outbreaks and epidemics.

Highly pathogenic avian influenza A virus subtype H5N1 is currently widespread in Asia, Europe, and Africa, with 60% mortality in humans. In particular, since 2009 Egypt has unexpectedly had the highest number of human cases of H5N1 virus infection, with more than 50% of the cases worldwide, but the basis for this high incidence has not been elucidated. A change in receptor binding affinity of the viral hemagglutinin (HA) from α2,3- to α2,6-linked sialic acid (SA) is thought to be necessary for H5N1 virus to become pandemic. In this study, we conducted a phylogenetic analysis of H5N1 viruses isolated between 2006 and 2009 in Egypt. The phylogenetic results showed that recent human isolates clustered disproportionally into several new H5 sublineages suggesting that their HAs have changed their receptor specificity. Using reverse genetics, we found that these H5 sublineages have acquired an enhanced binding affinity for α2,6 SA in combination with residual affinity for α2,3 SA, and identified the amino acid mutations that produced this new receptor specificity. Recombinant H5N1 viruses with a single mutation at HA residue 192 or a double mutation at HA residues 129 and 151 had increased attachment to and infectivity in the human lower respiratory tract but not in the larynx. These findings correlated with enhanced virulence of the mutant viruses in mice. Interestingly, these H5 viruses, with increased affinity to α2,6 SA, emerged during viral diversification in bird populations and subsequently spread to humans. Our findings suggested that emergence of new H5 sublineages with α2,6 SA specificity caused a subsequent increase in human H5N1 influenza virus infections in Egypt, and provided data for understanding the virus's pandemic potential., Author Summary Even though highly pathogenic avian H5N1 influenza viruses lack an efficient mechanism for human-human transmission, these viruses are endemic in birds in China, Indonesia, Viet Nam and Egypt. Hotspots for bird-human transmission are indicated in areas where human cases are more than 80% of total H5N1 influenza cases. Circulation among hosts may allow H5N1 virus to acquire amino acid changes enabling efficient bird-human transmission and eventually human-human transmission. The receptor specificity of viral hemagglutinin (HA) is considered a main factor affecting efficient transmissibility. Several amino acid substitutions in H5 virus HAs that increase their human-type receptor specificity have been described in virus isolates from patients, but their prevalence has been limited. In contrast, we show here that new H5 sublineages in Egypt have acquired a change in receptor specificity during their diversification in birds. We found that viruses in those sublineages exhibited increased attachment and infectivity in the human lower respiratory tract, but not in the larynx. Our findings may not allow a conclusion on the high pandemic potential of H5N1 virus in Egypt, but helps explain why Egypt has recently had the highest number of human H5 cases worldwide.

Three Gram-positive, strictly anaerobic, non-spore-forming, rod-shaped organisms (strains YIT 12062T, YIT 12063T and YIT 12064) were isolated from human faeces. Strain YIT 12062T was asaccharolytic and possessed a DNA G+C content of 58.3 mol%. Cells of strain YIT 12062T were negative for catalase, oxidase, urease, hydrolysis of aesculin and gelatin, nitrate reduction and indole production. Based on 16S rRNA gene sequence analysis, strain YIT 12062T was assigned to the genus Slackia (91.7–96.0 % sequence similarities to type strains of Slackia species). Biochemical data showed that the isolate was phenotypically distinct from all recognized species of the genus Slackia. Strain YIT 12062T therefore represents a novel species in the genus Slackia, for which the name Slackia piriformis sp. nov. is proposed. The type strain is YIT 12062T (=DSM 22477T=JCM 16070T). Following 16S rRNA gene sequence analysis, strains YIT 12063T and YIT 12064, which were isolated from different subjects, were shown to be most closely related to species of the genus Collinsella (93.8–95.1 % similarities to type strains). Although their phenotypic characteristics were very similar and they shared >99 % 16S rRNA gene sequence similarity and >97±1.8 % DNA–DNA relatedness, the two isolates could be discriminated by RAPD fingerprints. The DNA G+C contents of strains YIT 12063T and YIT 12064 were 60.8 and 61.0 mol%, respectively. They were saccharolytic in API test systems, positive for aesculin hydrolysis and negative for catalase, oxidase, urease, indole production, nitrate reduction and gelatin hydrolysis. The major end products of glucose fermentation of these strains were lactate, acetate and formate. Biochemical data supported the affiliation of strains YIT 12063T and YIT 12064 to the genus Collinsella and showed that they were phenotypically distinct from all recognized species of the genus Collinsella. Strains YIT 12063T and YIT 12064 therefore represent a novel species of the genus Collinsella, for which the name Collinsella tanakaei sp. nov. is proposed. The type strain is YIT 12063T (=DSM 22478T=JCM 16071T).

A novel strictly anaerobic, non-spore-forming, non-motile, non-flagellated, rod-shaped, Gram-negative bacterium (YIT 12066T) was isolated from human faeces. The isolate was negative for catalase, oxidase, urease, hydrolysis of aesculin and gelatin, nitrate reduction and indole production. The major end products of glucose metabolism were succinate and acetate. The major cellular fatty acids (>10 %) were C14 : 0, C18 : 1 ω7c, C18 : 1 ω9c, C16 : 1 ω7c and C16 : 0. The G+C content of the DNA was 40.3 mol%. 16S rRNA gene sequence analysis showed that strain YIT 12066T was most closely related to members of the family Succinivibrionaceae, with sequence similarity of 92–87 %. However, some phenotypic characteristics such as cellular morphology and the major fatty acid profile of strain YIT 12066T were markedly different from those of other members of the family Succinivibrionaceae. On the basis of both phylogenetic and phenotypic evidence, it is suggested that strain YIT 12066T represents a novel species in a new genus, for which the name Succinatimonas hippei gen. nov., sp. nov. is proposed; the type strain of Succinatimonas hippei is YIT 12066T (=DSM 22608T =JCM 16073T).

Introduction The objective of this investigation was to examine the factors influencing the long-term prognosis of autotransplanted teeth with complete root formation. Methods Thirty-eight teeth, autotransplanted in 32 patients, were examined more than 6 years after transplantation. Periodontal health, condition of restoration, mobility, occlusal contact, level of gingival margin, and course of orthodontic movement were investigated clinically and with radiographs. Results More than 6 years after autotransplanation, 33 teeth survived in 27 patients. The survival rate was 86.8% (mean observation time, 9.2 years). Abnormal findings were observed in 9 teeth, so the success rate was 63.1%. An inadequate root filling tended to give rise to abnormal findings. Conclusions The success of autotransplantation of a tooth with complete root formation is affected by the quality of root filling. When possible, clinicians should consider autotransplantation before root formation is complete.

The effects of isotocin (IT) and vasotocin (VT), which are fish analogues of mammalian oxytocin and vasopressin respectively, were examined in the isolated upper esophageal sphincter (UES) muscle. IT relaxed and VT constricted the UES muscle in a concentration-dependent manner. The relaxation by IT and the contraction by VT were completely blocked by H-9405 (an oxytocin receptor antagonist) and by H-5350 (a V(1)-receptor antagonist), respectively, suggesting that the eel UES possesses both IT and VT receptors. Truncated fragments of VT did not show any significant effects, indicating that all nine residues are essential for the VT and IT actions. IT may relax the UES muscle through enhancing cAMP production, since similar relaxation was also observed after treatment with 3-isobutyl-1-methylxantine, forskolin and 8-bromoadenosine, 3', 5'-cyclic mono-phosphate (8BrcAMP). Although 8-bromoguanosine, 3', 5'-cyclic monophosphate also relaxed the UES, its effect was less than 1/3 of that 8BrcAMP, suggesting minor contribution of nitric oxide (NO) in the relaxation of the UES muscle. Both peptides seem to act directly on the UES muscle, not through release of other substances from the epithelial cells, since similar relaxation and contraction were observed even in the scraped UES preparations. When IT and VT were intravenously administrated (in vivo experiments), the drinking rate of the seawater eel was enhanced by IT and was inhibited by VT. These effects correspond to the in vitro results described above, relaxation by IT and contraction by VT in the UES muscle. The significance of the relaxing effect by IT is discussed with respect to controlling the drinking behavior of the eel.

Borna disease virus (BDV) is a neurotropic virus that causes a persistent infection in the central nervous system (CNS) of many vertebrate species. Although a severe reactive gliosis is observed in experimentally BDV-infected rat brains, little is known about the glial reactions contributing to the viral persistence and immune modulation in the CNS. In this regard, we examined the expression of an astrocyte-derived factor, S100B, in the brains of Lewis rats persistently infected with BDV. S100B is a Ca 2+ -binding protein produced mainly by astrocytes. A prominent role of this protein appears to be the promotion of vascular inflammatory responses through interaction with the receptor for advanced glycation end products (RAGE). Here we show that the expression of S100B is significantly reduced in BDV-infected brains despite severe astrocytosis with increased glial fibrillary acidic protein immunoreactivity. Interestingly, no upregulation of the expression of S100B, or RAGE, was observed in the persistently infected brains even when incited with several inflammatory stimuli, including lipopolysaccharide. In addition, expression of the vascular cell adhesion molecule 1 (VCAM-1), as well as the infiltration of encephalitogenic T cells, was significantly reduced in persistently infected brains in which an experimental autoimmune encephalomyelitis was induced by immunization with myelin-basic protein. Furthermore, we demonstrated that the continuous activation of S100B in the brain may be necessary for the progression of vascular immune responses in neonatally infected rat brains. Our results suggested that BDV infection may impair astrocyte functions via a downregulation of S100B expression, leading to the maintenance of a persistent infection.

Borna disease virus (BDV) is a nonsegmented, negative-strand RNA virus that replicates and transcribes in the nucleus of infected cells. Recently, we have demonstrated that BDV phosphoprotein (P) can modulate its subcellular localization through binding to the protein X, which is encoded in the overlapping open reading frame (T. Kobayashi et al., J. Virol. 77: 8099-8107, 2003). This observation suggested a unique strategy of intracellular trafficking of a viral protein that is essential for the formation of a functional BDV ribonucleoprotein (RNP). However, neither the mechanism nor the consequences of the cytoplasmic retention or nuclear export of BDV X-P complex have been elucidated. In this study, we show that BDV P contains a bona fide nuclear export signal (NES) and can actively shuttle between the nucleus and cytoplasm. A transient transfection analysis of cDNA clones that mimic the BDV bicistronic X/P mRNA revealed that the methionine-rich (MetR) domain of P is responsible for the X-dependent cytoplasmic localization of the protein complex. Mutational and functional analysis revealed that the methionine residues within the MetR domain are critical for the activity of the NES of P. Furthermore, leptomycin B or small interfering RNA for inhibition of CRM1 strongly suggested that a CRM1-dependent pathway mediates nuclear export of P. Fluorescence loss in photobleaching analysis confirmed the nucleocytoplasmic shuttling of P. Moreover, we revealed that the nuclear export of P is not involved in the inhibition of the polymerase activity by X in the BDV minireplicon system. Our results may provide a unique strategy for the nucleocytoplasmic transport of viral RNP, which could be critical for the formation of not only infectious virions in the cytoplasm but also a persistent viral state in the nucleus.

Borna disease virus (BDV) is a highly neurotropic RNA virus that causes neurological disorders in many vertebrate species. Although BDV readily establishes lasting persistence, persistently infected cells maintain an apparently normal cell phenotype in terms of morphology, viability, and proliferation. In this study, to understand the regulation of stress responses in BDV infection, we investigated the expression of heat shock proteins (HSPs) in glial cells persistently infected with BDV. Interestingly, we found that BDV persistence did not upregulate HSP70 expression even in cells treated with heat stress. Furthermore, BDV-infected glial cells exhibited rapid rounding and detachment from the culture plate under various stressful conditions. Immunofluorescence analysis demonstrated that heat stress rapidly disrupts the cell cytoskeleton only in persistently infected cells, suggesting a lack of thermotolerance. Intriguingly, we found that although persistently infected glial cells expressed HSP70 mRNA after heat stress, its expression rapidly disappeared during the recovery period. These observations indicated that persistent BDV infection may affect the stability of HSP70 mRNA. Finally, we found that the double-stranded RNA-dependent protein kinase (PKR) is expressed at a constant level in persistently infected cells with or without heat shock. Considering the interrelationship between HSP70 and PKR production, our data suggest that BDV infection disturbs the cellular stress responses to abolish antiviral activities and maintain persistence.

Optical imaging derived from intrinsic signals such as blood volume and flow has enabled us to characterize the area of brain activation. Multi-spectral imaging of the change in cortical reflectance allows the determination of the change in the oxy-hemoglobin concentration independent of the deoxy-haemoglobin concentration. The changes in blood volume and oxygenation are closely related to the cerebral blood flow, and hence the simultaneous measurement of blood volume and flow in the cortical tissue must be beneficial for investigation of functional brain activation. Laser speckle flowgraphy has also been developed to visualize the blood flow in tissue and has been applied to measure the blood flow in tissue. In this study, a functional imaging system has been designed and assembled for the simultaneous measurement of the change in blood volume and flow in tissue. The optical systems of multi-spectral imaging and laser speckle flowgraphy are attached to the photo ports of the beam-splitter attachment of a stereo-microscope. The data of the multi-spectral image and speckle pattern of phantoms and finger are obtained for the initial experiments with the proposed system.

Laser Doppler flowmetry with a large source-detector spacing has been applied to measure blood perfusion in the deeper regions of tissue. The influence of the depth of perfusion on the Doppler spectrum for the large source-detector spacing is likely to be different from that for the conventional laser Doppler instruments with small source-detector spacing. In this study, the light propagation in a tissue model with a blood perfusion layer is predicted by the Monte Carlo simulation to discuss the influence of the depth of perfusion, blood volume, and source-detector spacing on the spectrum of the Doppler signal detected with large source-detector spacing. The influence of the depth of perfusion on the Doppler spectrum for the large source-detector spacing is different from that for the conventional laser Doppler instruments with small source-detector spacing, although the influence of source-detector spacing and blood volume on the Doppler spectrum for large source-detector spacing is almost the same as that for the conventional laser Doppler instruments. The influence of the depth of the perfusion on the Doppler spectrum depends on the path length that the detected light travels at different depths.

The Doppler power spectrum obtained from a tissue model with blood flow is predicted by Monte Carlo simulation. The depth of the blood flow affects the slope of the Doppler power spectrum. The results suggest that this phenomenon is caused by the effect of the multiple Doppler scattering by blood cells.

Naohiro, Ohtaki; Wataru, Kamitani; Yohei, Watanabe; Yohei, Hayashi; Hideyuki, Yanai; Kazuyoshi, Ikuta; Keizo, Tomonaga. Downregulation of an Astrocyte-Derived Inflammatory Protein, S100B, Reduces Vascular Inflammatory Responses in Brains Persistently Infected with Borna Disease Virus. Journal of Virology. 2007. 81(11), p.5940-5948.