Analysis of common antigen of flagella in Bacillus cereus and Bacillus thuringiensis

Abstract Flagellar antigen of Bacillus cereus H.1 was purified and tested for serodiagnostic antigen by ELISA. The antibody against the flagellar antigen of B. cereus H.1 reacted not only with the homologous specific antigen but also reacted with the flagellar antigens of 23 strains of B. cereus . This common flagellar antigen of B. cereus was found to be due to 61-kDa protein by SDS-PAGE and immunoblot assay. Monoclonal antibody H15A5 against common antigenic epitope of B. cereus also reacted with flagellar antigens of 21 strains of Bacillus thuringiensis by ELISA. This monoclonal antibody reacted with the 61-kDa protein of the flagella of B. cereus H.1 and H.2 and B. thuringiensis Kurstaki HD1, Alesti and Aizawai juroi by immunoblot analysis. These results indicated that the common antigenic epitope of the 61-kDa protein existed in the flagella both of B. cereus and B. thuringiensis .     

A recombinant foot-and-mouth disease virus antigen inhibits DNA replication and triggers the SOS response in Escherichia coli

Abstract The 3D gene of foot-and-mouth disease virus encodes the viral RNA dependent RNA polymerase, also called virus infection associated (VIA) antigen, which is the most important serological marker of virus infection. This 3D gene from a serotype Cl virus has been cloned and overexpressed in Escherichia coli under the control of the strong lambda lytic promoters. The resulting 51 kDa recombinant protein has been shown to be immunoreactive with sera from infected animals. After induction of gene expression, an immediate and dramatic arrest of cell DNA synthesis occurs, similar to that produced by genotoxic doses of the drug mitomycin C. This effect does not occur during the production of either a truncated VIA antigen or other related and non-related viral proteins. The inhibition of DNA replication results in a subsequent induction of the host SOS DNA-repair response and in an increase of the mutation frequency in the surviving cells.     

Ensembles of endothelial and mural cells promote angiogenesis in prenatal human brain

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Anatomically-based skeletal coordinate systems for use with impact biomechanics data intended for anthropomorphic test device development

Post-mortem human subjects (PMHS) are frequently used to characterize biomechanical response and injury tolerance of humans to various types of loading by means of instrumentation installed directly on the skeleton. Data extracted from such tests are often used to develop and validate anthropomorphic test devices (ATDs), which function as human surrogates in tests for injury assessment. Given that the location and orientation of installed instrumentation differs between subjects, nominally similar measurements made on different PMHS must be transformed to standardized, skeletal-based local coordinate systems (LCS) before appropriate data comparisons can be made. Standardized PMHS LCS that correspond to ATD instrumentation locations and orientations have not previously been published. This paper introduces anatomically-defined PMHS LCS for body regions in which kinematic measurements are made using ATDs. These LCS include the head, sternum, single vertebrae, pelvis, femurs (distal and proximal), and tibiae (distal and proximal) based upon skeletal landmarks extracted from whole body CT scans. The proposed LCS provide a means to standardize the reporting of PMHS data, and facilitate both the comparison of PMHS impact data across institutions and the application of PMHS data to the development and validation of ATDs.     

The monoclonal antibody 22/18 recognizes a conformational change in an intermediate filament of the newt,Notophthalmus viridescens,during limb regeneration

Summary Previous work has shown that the monoclonal antibody 22/18 identifies progenitor cells (blastemal cells) which depend on the nerve for their division in the early stages of limb regeneration in the newt,Notophthalmus viridescens. This antibody also reacts with cultured cells derived from the newt limb, and the intensity of immunoreactivity appears related to cell density and differentiation into myotubes. We report here that the monoclonal antibody 22/18 recognizes a polypeptide (22/18 antigen) which is intracellular and filamentous. Double staining of cells with 22/18 monoclonal antibody and antibodies against various cytoskeletal components indicates that the epitope is expressed on an intermediate filament component. Although this antibody is specific for blastemal cells in cryostat sections of the regenerating limb, its reactivity on immunoblots is not confined to this tissue. The 22/18 antigen is differentially affected by aldehyde fixatives distinguished by the spacing of their reactive groups. While formaldehyde fixation impairs detection of the antigen, ethylene glycol-bis[succinic acid n-hydroxysuccinimide ester] reveals the antigen in sections of normal and regenerating limbs in a distribution that is consistent with the one obtained from immunoblots. We suggest that the 22/18 monoclonal antibody detects a change in protein conformation, probably related to changes in the physiological state of the cell, that occurs transiently during regeneration and possibly during development.     

A new role for PGRP-S (Tag7) in immune defense: lymphocyte migration is induced by a chemoattractant complex of Tag7 with Mts1

PGRP-S (Tag7) is an innate immunity protein involved in the antimicrobial defense systems, both in insects and in mammals. We have previously shown that Tag7 specifically interacts with several proteins, including Hsp70 and the calcium binding protein S100A4 (Mts1), providing a number of novel cellular functions. Here we show that Tag7–Mts1 complex causes chemotactic migration of lymphocytes, with NK cells being a preferred target. Cells of either innate immunity (neutrophils and monocytes) or acquired immunity (CD4⁺ and CD8⁺ lymphocytes) can produce this complex, which confirms the close connection between components of the 2 branches of immune response.     

The Invisibility of Disability: Using Dance to Shake from Bioethics the Idea of ‘Broken Bodies’

Complex social and ethical problems are often most effectively solved by engaging them at the messy and uncomfortable intersections of disciplines and practices, a notion that grounds the InVisible Difference project, which seeks to extend thinking and alter practice around the making, status, ownership, and value of work by contemporary dance choreographers by examining choreographic work through the lenses of law, bioethics, dance scholarship, and the practice of dance by differently‐abled dancers. This article offers a critical thesis on how bioethics has come to occupy a marginal and marginalizing role in questions about the differently‐abled body. In doing so, it has rendered the disabled community largely invisible to and in bioethics. It then defends the claim that bioethics – as a social undertaking pursued collaboratively by individuals from different disciplines – must take much better notice of the body and the embodied individual if it is to better achieve its ends, which include constructing a moral and just society. Finally, this article considers how the arts, and specifically dance (and here dance by differently‐abled dancers), provides us with rich evidence about the body and our ability to respond positively to normally ‘othered’ bodies. It concludes that greater attention to empirical evidence like that being generated in InVisible Difference will help to expand the reach and significance of bioethics, and thereby its relevance to (and consciousness of) important questions about the status of bodies and bodily differences, which must be considered as central to its ambitions.     

The congenital cataract-causing mutations P20R and A171T are associated with important changes in the amyloidogenic feature,structure and chaperone-like activity of human αB-crystallin

Cataract is the major reason for human blindness worldwide. α-Crystallin, as a key chaperone of eye lenses, keeps the lenticular tissues in its transparent state over time. In this study, cataract-causing familial mutations, P20R and A171T, were introduced in CRYАB gene. After successful expression in Escherichia coli and subsequent purification, the recombinant proteins were subjected to extensive structural and functional analyses using various spectroscopic techniques, gel electrophoresis, and electron microscopy. The results of fluorescence and Raman assessments suggest important but discreet conformational changes in human αB-Cry upon these cataractogenic mutations. Furthermore, the mutant proteins exhibited significant secondary structural alteration as revealed by FTIR and Raman spectroscopy. An increase in conformational stability was seen in the human αB-Cry bearing these congenital cataractogenic mutations. The oligomeric size distribution and chaperone-like activity of human αB-Cry were significantly altered by these mutations. The P20R mutant protein was observed to loose most of the chaperone-like activity. Finally, these cataractogenic mutant proteins exhibited an increased propensity to form the amyloid fibrils when incubated under environmental stress. Overall, the structural and functional changes in mutated human αB-Cry proteins can shed light on the pathogenic development of congenital cataracts.     

A method for the harvest,culture, and characterization of human adult atrial myocardial cells: Correlation with age of donor

Summary Myocardial cell culture methods are now well established for animal and fetal human tissue. We present here a method for harvesting and culturing adult human atrial myocardiocytes. Cells are obtained from fresh atrial tissue normally discarded after being removed to cannulate the right atrium during open heart surgery. The atrial tissue is minced and then digested using collagenase. The single cell suspension is initially cultured in serum-containing growth medium, then transferred to defined medium, selective for myocardial cell growth. The cells are characterized by immunoperoxidase stains and transmission electron microscopy. The cultured cells stain positive for myoglobin, whereas control cultured fibroblasts and endothelial cells do not. Electron microscopy shows the presence of numerous myofibrils, Z-bodies, pleomorphic mitochondria, and secretory granules. The chronological age of the donor was an important factor in culturing the adult tissue, the younger tissue correlated with a higher success rate. This method provides a means for in vitro study of human adult myocardial cells and provides guidelines for appropriate atrial tissue to use.