Disturbance-induced bird diversity in early successional habitats in the humid temperate region of northern Japan

The positive role of moderate natural disturbance is less known for a mobile organism such as birds, compared to sessile organisms. In the face of recent declines of grassland birds, it is necessary to identify the mechanism to maintain avian diversity in early successional open habitats in different regions. In the humid temperate region, the predominant habitat type is woody vegetation. Therefore, bird communities were studied along vegetational succession using a chronosequence method. TWINSPAN identified three distinctive habitat types (barren, grass-fen and shrubland) and four habitat guilds of birds (pioneer, grassland, ubiquitous and shrub) in the study sites. Path analysis determined the direct and indirect effects of disturbance on the habitat guilds of birds. Short and intermediate intervals of the water disturbance are important to pioneer guilds and grass-fen habitat, respectively. The frequent occurrence of large animals had a negative impact on grassland guild. It suggests that grassland birds less tolerate cattle grazing or human activities in a region with intensive land use. The chronosequence study revealed the dynamic nature of the bird community. Birds occupy habitats following the successional sere of vegetation, responding to animal occurrence and human activities in various manners.     

The dominant bacteria shifted from the order “ Lactobacillales ” to Bacillales and Actinomycetales during a start-up period of large-scale, completely-mixed composting reactor using plastic bottle flakes as bulking agent

Bacterial community succession in the start-up of a large-scale, completely-mixed composting reactor was analyzed by 16S rRNA gene (16S rDNA) clone analysis and denaturing gradient gel electrophoresis (DGGE) combined with measurements of temperature, pH, moisture contents, and decomposing rate. DGGE analysis and physicochemical parameters showed that bacterial community succession occurred in four phases; (1) at the start of operation and pH decreasing period (day 0–3), (2) pH decreased and increased period (day 4–11), (3) middle term, moisture content decreasing and maximum temperature increased period (day 12–16) and (4) latter term, temperature decreasing period (day 17–24). Lactobacillus spp. and Bacillus coagulans were detected from the initial phase and middle term, respectively. 16S rDNA clone analysis showed that the dominant bacteria shifted from the order “Lactobacillales” to Bacillales and Actinomycetales. The order “Lactobacillales” was unique which may be caused by using the plastic bottle flakes (polyethylene terephthalate, PET) as bulking agent.     

Human immunodeficiency virus type 1 Vpr interacts with spliceosomal protein SAP145 to mediate cellular pre-mRNA splicing inhibition

Vpr, an accessory gene product of human immunodeficiency virus type 1 (HIV-1), affects both viral and cellular proliferation by mediating long terminal repeat activation, cell cycle arrest at the G2 phase, and apoptosis. We previously found that Vpr plays a novel role as a regulator of pre-mRNA splicing both in vivo and in vitro. However, the cellular target of Vpr, as well as the mechanism of cellular pre-mRNA splicing inhibition by Vpr, is unknown. Here, we show clearly that Vpr inhibits the splicing of cellular pre-mRNA, such as beta-globin pre-mRNA and immunoglobulin (Ig) M pre-mRNA and that the third alpha-helical domain and arginine-rich region are important its ability to inhibit splicing. Additionally, using mutants with specific substitutions in two domains of Vpr, we demonstrated that the interaction between Vpr and SAP145, an essential splicing factor, was indispensable for splicing inhibition. Finally, co-immunoprecipitation and in vitro competitive binding assays indicated that Vpr associates with SAP145 and interferes with SAP145-SAP49 complex formation. Thus, these results suggest that cellular expression of Vpr may block spliceosome assembly by interfering with the function of the SAP145-SAP49 complex in host cells.     

Novel phenotype in beagle dogs characterized by skin response to compound 48/80 focusing on skin mast cell degranulation

Beagle dogs have long been employed in toxicology studies and as skin disease models. Compared with other experimental animal species, they are known to be susceptible to skin responses, such as rashes, from exposure to various chemical compounds. Here, a unique dog phenotype was identified that showed no skin response to compound 48/80, a mast cell degranulating agent. Although the skin responses to intradermal injection of polyoxyethylene castor oil derivative (HCO-60, a nonionic detergent), histamine dihydrochloride, concanavalin A (IgE receptor-mediated stimuli), or calcium ionophore {"type":"entrez-nucleotide","attrs":{"text":"A23187","term_id":"833253","term_text":"A23187"}}A23187 were comparable in wild-type (WT) dogs and these nonresponder (NR) dogs, only the response to compound 48/80 was entirely absent from NR dogs. The skin mast cell density and histamine content per mast cell were histologically comparable between WT and NR dogs. By checking for skin responses to compound 48/80, NR dogs were found to exist at the proportion of 17–20% among four animal breeders. From retrospective analysis of in-house breeding histories, the NR phenotype appears to conform to the Mendelian pattern of recessive inheritance. The standard skin response in WT dogs developed at 2–4 months of age. In conclusion, this unique phenotype, typified by insensitivity in the compound 48/80-induced degranulation pathway in mast cells, has been widely retained by recessive inheritance in beagle dogs among general experimental animal breeders. The knowledge concerning this phenotype could lead to better utilization of dogs in studies and aid in model development.     

Identification of phosphoproteins associated with maintenance of transformed state in temperature-sensitive Rous sarcoma-virus infected cells by proteomic analysis

To identify phosphotyrosine-containing proteins essential for maintaining the transformed state, we studied the tyrosine phosphorylation profile of temperature-sensitive mutant of Rous sarcoma virus, tsNY68, infected cells (68N7). Shifting the temperature from 39 degrees C (nonpermissive) to 32 degrees C (permissive) markedly increased the expression of phosphotyrosine-containing cell membrane proteins of approximately 40kDa, as assessed by SDS-PAGE. Membrane and nuclear proteins were separated by two-dimensional gel electrophoresis and immunoblotted with anti-phosphotyrosine antibody. Proteins showing temperature-dependent changes in phosphorylation profile were subjected to in-gel digestion with trypsin and analyzed by mass spectrometry. Five proteins were identified: heterogeneous nuclear ribonucleoprotein (hnRNP) A3, hnRNP A2, annexin II, phosphoglycerate mutase 1, and triosephosphate isomerase 1. hnRNP A3 was phosphorylated at serine residues and had both serine and tyrosine phosphorylated sites. These results suggest an important complementary role for proteomics in identifying molecular abnormalities associated with tumor progression that may be attractive candidates for tumor diagnosis.     

rAAV-mediated shRNA ameliorated neuropathology in Huntington disease model mouse

Huntington disease (HD) is a fatal progressive neurodegenerative disorder associated with expansion of a CAG repeat in the first exon of the gene coding the protein huntingtin (htt). Although the feasibility of RNA interference (RNAi)-mediated reduction of htt expression to attenuate HD-associated symptoms is suggested, the effects of post-symptomatic RNAi treatment in the HD model mice have not yet been certified. Here we show the effects of recombinant adeno-associated virus (rAAV)-mediated delivery of RNAi into the HD model mouse striatum after the onset of disease. Neuropathological abnormalities associated with HD, such as insoluble protein accumulation and down-regulation of DARPP-32 expression, were successfully ameliorated by the RNAi transduction. Importantly, neuronal aggregates in the striatum were reduced after RNAi transduction in the animals comparing to those at the time point of RNAi transduction. These results suggest that the direct inhibition of mutant gene expression by rAVV would be promising for post-symptomatic HD therapy.     

Quartz crystal microbalance immunosensors for environmental monitoring

This paper presents discussion of quartz crystal microbalance (QCM) immunosensors for environmental monitoring. Factors limiting the practical application of antibodies to analytical problems are also presented. Among several candidates for the QCM immunosensor device, selected QCM devices and oscillating circuits were tested thoroughly and developed to obtain highly stable and sensitive frequency signals. The biointerface of QCM immunosensor was designed and controlled to immobilize antibody on the QCM surface, to reduce non-specific binding and to suppress denaturation of immobilizing antibody by self-assembled monolayer technique and artificial phospholipid (2-methacryloyloxyethyl phosphorylcholine (MPC)) polymer. MPC polymer as a antibody-stabilizing reagent was added to reduce non-specific binding of the antigen solution and stabilize the immunologic activity of the antibody-immobilized QCM. In addition, it provides examples for detection and quantitation of environmental samples using QCM immunosensors. The analytical results for fly ash extracted samples of dioxins using the QCM immunosensor indicated a good relationship with GC/MS methods. The integrating protocols of the competitive immunoassay and signal-enhancing step are for detecting low molecular analytes with extremely low detection limits using an QCM immunosensor. Furthermore, its detect limitation was extended from 0.1 to 0.01 ng/ml by the signal-enhancing step when the anti-bisphenol-A antibody conjugated MPC polymeric nanoparticles was used. The QCM immunosensor method has demonstrated its effectiveness as an alternative screening method for environmental monitoring because these results were compared with results obtained through environmental monitoring methods such as ELISA and GC/MS.     

Dioxin immunosensor using anti-2,3,7,8-TCDD antibody which was produced with mono 6-(2,3,6,7-tetrachloroxanthene-9-ylidene) hexyl succinate as a hapten

To detect dioxin using a quartz crystal microbalance (QCM) immunosensor, anti-2,3,7,8-tetrachloro-p-dibenzodioxin (TCDD) monoclonal antibodies (MAbs) were produced as types of IgG1 and IgM, with mono 6-(2,3,6,7-tetrachloroxanthene-9-ylidene) hexyl succinate (as a hapten) conjugated with bovine serum albumin (dioxin-BSA). Furthermore, ScFv was generated from hybridoma-producing IgG1 MAb. Among these antibodies, ScFv showed excellent capability for dioxin detection using QCM immunosensors.     

Characterization of Neutralizing Epitopes of Varicella-Zoster Virus Glycoprotein H

Varicella-zoster virus (VZV) glycoprotein H (gH) is the major neutralization target of VZV, and its neutralizing epitope is conformational. Ten neutralizing human monoclonal antibodies to gH were used to map the epitopes by immunohistochemical analysis and were categorized into seven epitope groups. The combinational neutralization efficacy of two epitope groups was not synergistic. Each epitope was partially or completely resistant to concanavalin A blocking of the glycomoiety of gH, and their antibodies inhibited the cell-to-cell spread of infection. The neutralization epitope comprised at least seven independent protein portions of gH that served as the target to inhibit cell-to-cell spread.     

Topoisomerase IIα inhibition following DNA transfection greatly enhances random integration in a human pre-B lymphocyte cell line

DNA transfection can be too inefficient to establish a desired number of stable transfectants, particularly in lymphocytes; however, this could be circumvented by increasing the absolute frequency of random integration. In this paper, we show that treating cells with topoisomerase II inhibitor following electroporation greatly (∼10- to 20-fold) enhances random integration of input DNA in a human pre-B lymphocyte cell line, Nalm-6. With the use of various kinds of topoisomerase II-targeting agents, we also present evidence that topoisomerase IIα inhibition is critical for the enhancement of random integration, while the contribution of topoisomerase IIβ may be negligible. As topoisomerase IIα is highly expressed in vigorously growing cells, our results show that topoisomerase IIα inhibition provides a promising way of enhancing random integration in virtually all cultured cell lines.