Pathogenicity of Treponema denticola Wild-Type and Mutant Strain Tested by an Active Mode of Periodontal Infection Using Microinjection

The available passive mode of periodontal infections in mice requires high efficiency of bacterial attachment and invasiveness and is not always suitable to test the pathogenicity of genetically engineered mutant strains. We developed an active mode of oral infection, using microinjection in the marginal gingiva of mice, to test the pathogenicity of a genetically engineered Treponema denticola mutant strain deficient in intermediate-like filaments, compared to the wild-type strain. This targeted mode of infection inoculates the bacterial strain to be tested directly at a lesion site (needle entry point) located at the future periodontal lesion site. The efficiency of T. denticola wild-type strain to elicit bone loss contrasted with the lack of pathogenicity of the intermediate-like filament deficient mutant strain in comparison to the sham infection. The periodontal microinjection oral model in mice can be used for a variety of applications complementary to the passive mode of periodontal infection in context of pathogenicity testing

Identifying Emerging Research Related to Solar Cells Field using a Machine Learning Approach

The number of research papers related to solar cells field is increasing rapidly. It is hard to grasp research trends and to identify emerging research issues because of exponential growth of publications, and the field’s subdivided knowledge structure. Machine learning techniques can be applied to the enormous amounts of data and subdivided research fields to identify emerging researches. This paper proposed a prediction model using a machine learning approach to identify emerging solar cells related academic research, i.e. papers that might be cited very frequently within three years. The proposed model performed well and stable. The model highlighted some articles published in 2015 that will be emerging in the future. Research related to vegetable-based dye-sensitized solar cells was identified as the one of the promising researches by the model. The proposed prediction model is useful to gain foresight into research trends in science and technology, facilitating decision-making processes

(14)C ages of Quaternary deposits in Kojima Lake area, Tamano City, Okayama Prefecture

Two 14C ages are obtained from drilled core samples in Kojima Lake area. One is 7920±250 y.B.P. from peat which is just below silty clay of bay sediments (-14.30-14.61 m) The other is 24900+3450,-2450 y.B.P. from pale milky gray clay of fluvial sediments (-24.15-24.45 m)

Fluorescence and Electron Microscopic Studies of the Cytoskeletal Organi­zation of Normal, Established and Transformed Chick Embryo Cells

The cytoskeletons of two established chick embryo cell (CEC) lines were examined by fluorescence and electron microscopy and compared with those of control cells and cells transformed by Rous sarcoma virus (RSV). In normal CEC, many stress fibers were observed. On the other hand, stress fibers were disorganized in nontransformed spontaneously established CEC, non-tumorigenic CEC partially transformed with a chemical carcinogen, and tumorigenic RSV-transformed CEC. In the normal CEC, actin filaments formed several bundles along the processes of the cell. Stereo-images of the peripheral region revealed bundles of filaments which were located along the attached side to the substrate. A fine well preserved network of filaments was also observed. On the other hand, in spontaneously established, partially transformed and RSV-transformed CEC, a fine network of filaments, but no actin cables, was found. These results support previous evidence that the cytoskeletal changes themselves are not directly related to the transformation or tumorigenicity of cells. </p