Unmodified Version Research Articles

Microcin E492 Amyloid Formation Is Retarded by Posttranslational Modification

Microcin E492, a channel-forming bacteriocin with the ability to form amyloid fibers, is exported as a mixture of two forms: unmodified (inactive) and posttranslationally modified at the C terminus with a salmochelin-like molecule, which is an essential modification for conferring antibacterial activity. During the stationary phase, the unmodified form accumulates because expression of the maturation genes mceIJ is turned off, and microcin E492 is rapidly inactivated. The aim of this work was to demonstrate that the increase in the proportion of unmodified microcin E492 augments the ability of this bacteriocin to form amyloid fibers, which in turn decreases antibacterial activity. To this end, strains with altered proportions of the two forms were constructed. The increase in the expression of the maturation genes augmented the antibacterial activity during all growth phases and delayed the loss of activity in the stationary phase, while the ability to form amyloid fibers was markedly reduced. Conversely, a higher expression of microcin E492 protein produced concomitant decreases in the levels of the modified form and in antibacterial activity and a substantial increase in the ability to form amyloid fibers. The same morphology for these fibers, including those formed by only the unmodified version, was observed. Moreover, seeds formed using exclusively the nonmodified form were remarkably more efficient in amyloid formation with a shorter lag phase, indicating that the nucleation process is probably improved. Unmodified microcin E492 incorporation into amyloid fibers was kinetically more efficient than the modified form, probably due to the existence of a conformation that favors this process.

Enhanced sialylation and in vivo efficacy of recombinant human α-galactosidase through in vitro glycosylation

Human α-galactosidase A (GLA) has been used in enzyme replacement therapy for patients with Fabry disease. We expressed recombinant GLA from Chinese hamster ovary cells with very high productivity. When compared to an approved GLA (agalsidase beta), its size and charge were found to be smaller and more neutral. These differences resulted from the lack of terminal sialic acids playing essential roles in the serum half-life and proper tissue targeting. Because a simple sialylation reaction was not enough to increase the sialic acid content, a combined reaction using galactosyltransferase, sialyltransferase, and their sugar substrates at the same time was developed and optimized to reduce the incubation time. The product generated by this reaction had nearly the same size, isoelectric points, and sialic acid content as agalsidase beta. Furthermore, it had better in vivo efficacy to degrade the accumulated globotriaosylceramide in target organs of Fabry mice compared to an unmodified version. [BMB Reports 2013; 46(3): 157-162]

Initial Validity and Reliability Data on the Columbia–Suicide Severity Rating Scale

Back to table of contents Previous article Next article Communications and UpdatesFull AccessInitial Validity and Reliability Data on the Columbia–Suicide Severity Rating ScalePhillip Chappell, M.D., Douglas E. Feltner, M.D., Clare Makumi, Pharm.D., and Michelle Stewart, Ph.D.Phillip ChappellMembers of the International Society for CNS Clinical Trials and Methodology Suicide Ideation and Behavior Working GroupSearch for more papers by this author, M.D., Douglas E. FeltnerMembers of the International Society for CNS Clinical Trials and Methodology Suicide Ideation and Behavior Working GroupSearch for more papers by this author, M.D., Clare MakumiMembers of the International Society for CNS Clinical Trials and Methodology Suicide Ideation and Behavior Working GroupSearch for more papers by this author, Pharm.D., and Michelle StewartMembers of the International Society for CNS Clinical Trials and Methodology Suicide Ideation and Behavior Working GroupSearch for more papers by this author, Ph.D.Published Online:1 Jun 2012https://doi.org/10.1176/appi.ajp.2012.12010123AboutSectionsPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InEmail To the Editor: We welcome the article by Posner et al. (1) in the December 2011 issue that provides initial psychometric data on the Columbia–Suicide Severity Rating Scale (C-SSRS). Analyses of data on the psychometric properties of the C-SSRS have lagged behind its widespread adoption in clinical trials and other settings. Although retrospective in nature and limited in generalizability, the results presented by Posner et al. support the validity of the C-SSRS and provide evidence for the internal consistency of the ideation intensity subscale. However, published data on interrater reliability of the severity of ideation and behavior subscales of the C-SSRS are limited, inconsistent, and based on different versions of the instrument (2, 3). Additional prospective studies of the interrater reliability of the current instrument are needed.There is also an urgent need to examine the performance of the C-SSRS in special populations, such as children and patients with dementia. The C-SSRS is widely utilized in clinical trials to assess suicide risk in children as young as 6 years old. Despite significant developmental differences in language and understanding of concepts such as death, an unmodified version of the instrument is often used for children from 6 to 17 years old. Moreover, the pediatric experience of the individuals administering the instrument to young children varies widely, and related operational challenges, such as the inclusion of caregiver input, have not been fully addressed. A pediatric version of the C-SSRS is available but has found only limited use, and no separate validity and reliability data are available on the use of any version of the C-SSRS for children younger than 12.Similarly, studies of patients with mild cognitive impairment or Alzheimer's disease frequently include assessment with the C-SSRS. Here again, there are no established objective guidelines on using the C-SSRS with patients at different stages of cognitive decline. As in the case of young children, no separate validity and reliability data are available on the use of the C-SSRS in cognitively impaired patients despite its widespread adoption.The study by Posner et al. is an important first step toward establishing the validity and reliability of an assessment tool that has rapidly found widespread use in academic and industry-sponsored clinical trials spanning multiple indications in diverse patient populations. Extensive data sets based on the C-SSRS have accumulated and will be analyzed for signal detection of suicidal ideation and behavior. The results of these analyses will be valid and reliable only to the extent that the C-SSRS itself is demonstrated to be valid and reliable in the diverse patient populations to which its use has been extended.Members of the International Society for CNS Clinical Trials and Methodology Suicide Ideation and Behavior Working GroupDr. Chappell and Dr. Stewart are full-time employees of Pfizer. Dr. Feltner has received consulting fees from Astellas, Ironwood, Merck, National Institute of Neurological Disorders and Stroke, Novartis, Ono, Takeda, and Toyama; he is consulting chief medical officer at and holds stock options in Embera Neurotherapeutics; he has equity interest in Eli Lilly and Pfizer; and he is a former employee of Pfizer. Dr. Makumi is a full-time employee of GlaxoSmithKline.Accepted for publication in March 2012.

Real‐Time Fluid Effects on Surfaces using the Closest Point Method

AbstractThe Closest Point Method (CPM) is a method for numerically solving partial differential equations (PDEs) on arbitrary surfaces, independent of the existence of a surface parametrization. The CPM uses a closest point representation of the surface, to solve the unmodified Cartesian version of a surface PDE in a 3D volume embedding, using simple and well‐understood techniques. In this paper, we present the numerical solution of the wave equation and the incompressible Navier‐Stokes equations on surfaces via the CPM, and we demonstrate surface appearance and shape variations in real‐time using this method. To fully exploit the potential of the CPM, we present a novel GPU realization of the entire CPM pipeline. We propose a surface‐embedding adaptive 3D spatial grid for efficient representation of the surface, and present a high‐performance approach using CUDA for converting surfaces given by triangulations into this representation. For real‐time performance, CUDA is also used for the numerical procedures of the CPM. For rendering the surface (and the PDE solution) directly from the closest point representation without the need to reconstruct a triangulated surface, we present a GPU ray‐casting method that works on the adaptive 3D grid.

Liberal Multiculturalism as Political Philosophy

The fact that certain versions of multiculturalism conflict with basic democratic and liberal principles should no longer come as surprise. Rather, it may be taken to define multiculturalism in contradistinction to soft multiculturalism - such as Jens-Martin Eriksen and myself argue in the forthcoming The Democratic Contradictions of Multiculturalism} As an example, Charles Taylor seems willing to go some way in the direction of renouncing general liberal principles and may thus count as multiculturalist (even if one with scruples). A philosopher who has, to greater degree, attempted to involve core liberal ideas of individual rights and tolerance is the leading theoretician of multiculturalism in philosophy, the Canadian Will Kymlicka. With Multicultural Citizenship (1985) he produced new classic in the field, recently continued in Multicultural Odysseys (2007). Kymlicka is especially interesting because he directly addresses the question about the relation between multicultural norms and general principles of liberal democracy - such as is indicated by the subtitle of his chef-d'oeuvre: a liberal theory for multiculturalism. His explicit idea is that it is possible to articulate multiculturalism which constitutes further development of basic liberal ideas of democracy, human rights etc. and thus is not only compatible with liberalism but may even be seen as higher stage of liberalism. It might be expressed more problematically in way with which he may not himself be satisfied: Kymlicka seeks middle road between culturalism and liberalism.His project rests on an attempt to reconcile some of the ontological presuppositions of culturalism, according to which individuals are thoroughly determined by their and may only lead satisfying life within the confines of that culture,2 with basically liberal philosophy - by trying to develop the former out of the latter. His concept of is obviously culturalist: he delimits it from the broad and more indistinct use of the notion of comprising gay culture or Western culture (18) by focusing upon what he calls culture specifically: a which provides its members with meaningful ways of life across the full range of human activities, including social, educational, religious, recreational, and economic Ufe, encompassing both public and private spheres.3This forms relatively unmodified version of the all-embracing concept of in culturalism - even if we notice the conspicuous absence of adjectives like juridical and political in his list of the full range of human activities in such He emphasizes that such full necessarily exists in institutional incarnations. If should be able to survive and develop in the modern world, it must necessarily be such culture, he claims (80), and the intimate connection of such with the concept of liberty forms the basis of the central argument axis in the book. This goes as follows: freedom involves making choices amongst various options, and our societal not only provides these options, but also makes them meaningful to us ... . And to have belief about the value of practice is, in the first instance, matter of understanding the meanings attached to it by our culture. (83) As is evident, this is variant of basic culturalist ideas: the claim that thought and value systems originate exhaustively from Kymlicka even goes so far as to quote Margalit and Raz wim acclamation for their claim that familiarity with determines the boundaries of the imaginable (89) - the Wittgenstein-like idea that the limits of my form the limit of fantasy. This is really hard and conservative version of culturalism.To the same complex of ideas also belongs the radical idea that the self-esteem of persons is determined by what dignity their is ascribed. …

An interactive tool for the stock market research using recursive neural networks

The focus of this paper is to describe an application of a specific type of recurrent neural networks (RNN) in the domain of the technical analysis of the stock market. Said RNN is used as a tool that provides statistical information based on the historical time series processed in the training stage. In order to address certain questions of interest from the field of technical analysis of the financial markets, we introduce a set of constraints on the convergence of the state vector during the process of retrieval. Such approach retains its high computational efficiency notable in the unmodified version of the network, while it also provides an intuitive visualisation of the process of training and retrieval and thus facilitates an in-depth analysis of the system. We also present the pilot applications of exploiting information extracted from given time series to support an informed decision in an environment of real-time application.

SiRNA-optimized Modifications for Enhanced In Vivo Activity

Current modifications used in small interfering RNAs (siRNAs), such as 2'-methoxy (2'-OMe) and 2'-fluoro (2'-F), improve stability, specificity or immunogenic properties but do not improve potency. These modifications were previously designed for use in antisense and not siRNA. We show, for the first time, that the siRNA-optimized novel 2'-O modifications, 2'-O-benzyl, and 2'-O-methyl-4-pyridine (2'-O-CH2Py(4)), are tolerated at multiple positions on the guide strand of siRNA sequences in vivo. 2'-O-benzyl and 2'-O-CH2Py(4) modifications were tested at each position individually along the guide strand in five sequences to determine positions that tolerated the modifications. The positions were combined together and found to increase potency and duration of siRNAs in vivo compared to their unmodified counterparts when delivered using lipid nanoparticles. For 2'-O-benzyl, four incorporations were tolerated with similar activity to the unmodified siRNA in vivo, while for 2'-O-CH2Py(4) six incorporations were tolerated. Increased in vivo activity was observed when the modifications were combined at positions 8 and 15 on the guide strand. Understanding the optimal placement of siRNA-optimized modifications needed for maximal in vivo activity is necessary for development of RNA-based therapeutics.

Lost in Translation? Some Issues Encountered in Transferring Village Design Statements from England to Ireland

The erosion of the distinctive character of smaller rural settlements in England has been addressed with some success through the preparation of Village Design Statements (VDS) by local communities. Adopting a more or less unmodified version of the English VDS model, the Heritage Council introduced a VDS programme in Ireland in 2000. This paper reports on an evaluation of that programme and indicates that VDSs in Ireland have had very limited success to date in terms of their stated objectives. The paper reflects on some of the difficulties experienced in transferring an established community-led initiative from one cultural, political and institutional context to another, and concludes that aspects of that context need to be addressed before VDSs are likely to redress the loss of distinctiveness in villages in Ireland or elsewhere. Further, it concludes that in many situations a community-led instrument embracing broader social, economic and environmental matters might be more appropriate than a VDS.

Modification of citrulline residues with 2,3‐butanedione facilitates their detection by liquid chromatography/mass spectrometry

Citrullination is a post-translational modification (PTM) that results from the deimination of the amino acid arginine into citrulline by Peptidyl Arginine Deiminase enzymes and occurs in a wide range of proteins in health and disease. This modification causes a 1 Da mass shift, which can be used to identify citrullination sites in proteins by the use of mass spectrometry. However, other PTMs, such as deamidation from asparagine to aspartic acid or from glutamine to glutamic acid, can also cause a 1 Da mass shift, making correct interpretation of the data more difficult. We developed a chemical tagging strategy which, combined with an open source search application, allowed us to selectively pinpoint citrullinated peptides in a complex mixture after liquid chromatography/mass spectrometry (LC/MS) analysis. After incubation of a peptide mixture with 2,3 butanedione, citrulline residues were covalently modified which resulted in a 50 Da shift in singly charged mass. By comparison of the peptide mass fingerprint from a modified and an unmodified version of the same sample, our in-house search application was able to identify the citrullinated peptides in the mixture. This strategy was optimized on synthetic peptides and validated on a digest of in vitro citrullinated fibrinogen, where different proteolytic enzymes were used to augment the protein coverage. This new method results in easy detection of citrullinated residues, without the need for complex mass spectrometry equipment.

Endocytosis of EphA receptors is essential for the proper development of the retinocollicular topographic map

Endocytosis of Eph-ephrin complexes may be an important mechanism for converting cell-cell adhesion to a repulsive interaction. Here, we show that an endocytosis-defective EphA8 mutant forms a complex with EphAs and blocks their endocytosis in cultured cells. Further, we used bacterial artificial chromosome transgenic (Tg) mice to recapitulate the anterior>posterior gradient of EphA in the superior colliculus (SC). In mice expressing the endocytosis-defective EphA8 mutant, the nasal axons were aberrantly shifted to the anterior SC. In contrast, in Tg mice expressing wild-type EphA8, the nasal axons were shifted to the posterior SC, as predicted for the enhanced repellent effect of ephrinA reverse signalling. Importantly, Rac signalling was shown to be essential for EphA-ephrinA internalization and the subsequent nasal axonal repulsion in the SC. These results indicate that endocytosis of the Eph-ephrin complex is a key mechanism by which axonal repulsion is generated for proper guidance and topographic mapping.

Angiogenin-induced tRNA-derived Stress-induced RNAs Promote Stress-induced Stress Granule Assembly

Angiogenin (ANG) is a secreted ribonuclease that cleaves tRNA to initiate a stress-response program in mammalian cells. Here we show that ANG inhibits protein synthesis and promotes arsenite- and pateamine A-induced assembly of stress granules (SGs). These effects are abrogated in cells transfected with the ANG inhibitor RNH1. Transfection of natural or synthetic 5'- but not 3'-tRNA fragments (tRNA-derived stress-induced RNAs; tiRNAs) induces the phospho-eukaryotic translation initiation factor 2alpha-independent assembly of SGs. Natural 5'-tiRNAs but not 3'-tiRNAs are capped with a 5'-monophosphate that is required for optimal SG assembly. These findings reveal that SG assembly is a component of the ANG- and tiRNA-induced stress response program.

Glycoengineered Acid α-Glucosidase With Improved Efficacy at Correcting the Metabolic Aberrations and Motor Function Deficits in a Mouse Model of Pompe Disease

Improving the delivery of therapeutics to disease-affected tissues can increase their efficacy and safety. Here, we show that chemical conjugation of a synthetic oligosaccharide harboring mannose 6-phosphate (M6P) residues onto recombinant human acid alpha-glucosidase (rhGAA) via oxime chemistry significantly improved its affinity for the cation-independent mannose 6-phosphate receptor (CI-MPR) and subsequent uptake by muscle cells. Administration of the carbohydrate-remodeled enzyme (oxime-neo-rhGAA) into Pompe mice resulted in an approximately fivefold higher clearance of lysosomal glycogen in muscles when compared to the unmodified counterpart. Importantly, treatment of immunotolerized Pompe mice with oxime-neo-rhGAA translated to greater improvements in muscle function and strength. Treating older, symptomatic Pompe mice also reduced tissue glycogen levels but provided only modest improvements in motor function. Examination of the muscle pathology suggested that the poor response in the older animals might have been due to a reduced regenerative capacity of the skeletal muscles. These findings lend support to early therapeutic intervention with a targeted enzyme as important considerations in the management of Pompe disease.

Identification of Two SET Domain Proteins Required for Methylation of Lysine Residues in Yeast Ribosomal Protein Rpl42ab

We show that the Saccharomyces cerevisiae ribosomal protein Rpl42ab (the identical product of the RPL42A and RPL42B genes) is monomethylated at Lys-40 and Lys-55. The methylation of Lys-40 is dependent upon the Ybr030w gene product; the methylation of Lys-55 is dependent upon the Set7 gene product. Ybr030w and SET7 genes both encode SET domain containing proteins homologous to known protein lysine methyltransferases, suggesting that their products are the specific enzymes responsible for the monomethylation of the two sites in Rpl42ab. We thus designate Ybr030w as Rkm3 and Set7 as Rkm4. Yeast strains with deletions in both the Ybr030w and SET7 genes produce unmethylated Rpl42ab. A slow growth phenotype was seen for the SET7 deletion strain and the double knock-out when grown in low concentrations of the eukaryotic protein synthesis inhibitor, cycloheximide. These results suggest that modification of Rpl42ab at Lys-55 can fine-tune its structure to avoid inhibition. An intact mass fragmentation approach ("top down mass spectrometry") was used to quantitate the extent of methylation of Rpl42ab. In wild-type strains, it was found that 78% was monomethylated at both Lys-40 and Lys-55 and that 22% was a mixture of species with either Lys-40 or Lys-55 monomethylated. The top down approach was also used to reevaluate the methylation sites of Rpl12ab. We found that the yeast Rpl12ab protein is dimethylated at the N-terminal proline residue, trimethylated at Lys-3 by Rkm2, and monomethylated at Arg-66.

DOES THE ENHANCEMENT OF CHEMOSENSORY STIMULI IMPROVE THE ENJOYMENT OF FOOD IN INSTITUTIONALIZED ELDERLY PEOPLE?

ABSTRACT Thirty‐six institutionalized elderly people and 45 young adults rated their degree of liking for different foods (first courses and fruit juice) modified in appearance, taste and flavor, as compared with unmodified version of the same foods. Taste and odor sensitivities were also measured in both age cohorts. The aim was to evaluate whether food with enhanced taste and flavor, and modified appearance was preferred by both young and elderly people, and to verify whether sensory performance influenced food preference. The elderly had a lower taste and odor abilities and more varying sensory performances than the young. Age had a significant effect on liking; the elderly scored higher than the young, especially for taste and flavor fortified food. Subdividing the elderly according to their sensory performance showed that performance did not influence liking for fruit juice, whereas it had a small, though nonsignificant, effect on first courses. PRACTICAL APPLICATIONSThe present article deals with the elderly people's food preference, an important, though poorly understood, topic. Although a steady increase in elderly population has been observed in recent years, institutionalized elderly people still represent a neglected part of the consumers. Because of elderly specific requirements, some interest is being paid to developing food formulations and dietary guidelines for institutionalized elderly people. In this study, the degree of liking for first courses and fruit juice commonly consumed in Italian nursing homes has been examined and compared with the young adults’ preferences. Taste and odor sensitivities were also measured and compared both to investigate whether age‐related differences in sensory performance could be observed and to examine, within the elderly group, the effect of taste and odor sensitivities on food preference. Results obtained may contribute to throw some light on elderly people's sensory perception and preference and help to improve food administration in nursing homes.

Estimation of Frequency for AM/FM Models Using the Phase Vocoder Framework

This paper proposes an extension of the applicability of phase-vocoder-based frequency estimators for generalized sinusoidal models, which include phase and amplitude modulations. A first approach, called phase corrected vocoder (PCV), takes into account the modification of the Fourier phases resulting from these modulations. Another approach is based on an adaptation of the principles of the time-frequency reassignment and is referred to as the reassigned vocoder (RV). The robustness of the estimation against noise is studied, both theoretically and experimentally, and the performance is assessed in comparison with two state-of-the-art algorithms: an unmodified version of the reassignment method and a quadratically interpolated fast Fourier transform method (QIFFT).

Simulation of Glazing Behavior in Fires using Computational Fluids Dynamics and Spectral Radiation Modeling

The performance and behavior of glazing systems have significant impact on fire growth and development. In the typical scenario of a glass pane exposed to fire, radiation is the predominant mode of heat transfer. In previous studies, the present authors have developed and validated a spectral radiation heat transfer model based on the Discrete Ordinates Method (SDOM) which accounts for the glass spectral properties (e.g. emissivity, transmissivity) and the diffuse nature of radiation incident on the glazing. In order to model the dynamic interaction between a glass pane and fire, the SDOM has been implemented in the CFD code FDS 5.0 and the new code (FDS-SDOM) is evaluated. The first part of FDS-SDOM validation study reports a comparative analysis between FDS-SDOM, the original (unmodified) version of FDS (OFDS) and the exact solutions for varying absorption coefficients typical of glass. The comparative study, in terms of radiative heat flux, shows that FDS-SDOM provides results closer to the exact solutions in comparison to OFDS when the absorption coefficient is varied from 0.1 to 100 m-1 (maximum error less than 1% for FDSSDOM against 13 % for FDS). This provides further justification for the need to account for varying spectral properties of material such as glass and the diffuse nature of radiation in calculations. In the second part of the validation study, FDS-SDOM is applied to two experimental fire and glass scenarios with the aim of predicting the transient temperature distribution in the glass. Relatively good agreements are found between the code’s predictions and the experimental data. The work demonstrates the good potential of combining the CFD approach with advanced spectral radiation modeling for fire and glazing studies.

How Explicit Instruction Makes a Difference: Metadiscourse Markers and EFL Learners' Reading Comprehension Skill

This study attempted to determine the effect of explicit instruction of metadiscourse markers on pre-intermediate EFL learners' reading comprehension skill. To this end, 90 students were selected following a pre-test and divided randomly into three groups. Then three versions of the same test, original, modified and unmodified metadiscourse-free texts, were provided. Results revealed that the group receiving the original version outperformed the group with the unmodified version, but their performance was about equal with the group receiving the modified version. In addition, two of the groups answered a questionnaire on how they judged the texts. Next, one of the groups received instruction on metadiscourse. Finally, a posttest was administered. Results revealed the positive influence of form-focused instruction of metadiscourse. It also revealed that metadiscourse markers are primarily responsible for cohesion rather than coherence.

First-Order Classical Modal Logic

The paper focuses on extending to the first order case the semantical program for modalities first introduced by Dana Scott and Richard Montague. We focus on the study of neighborhood frames with constant domains and we offer in the first part of the paper a series of new completeness results for salient classical systems of first order modal logic. Among other results we show that it is possible to prove strong completeness results for normal systems without the Barcan Formula (like FOL + K)in terms of neighborhood frames with constant domains. The first order models we present permit the study of many epistemic modalities recently proposed in computer science as well as the development of adequate models for monadic operators of high probability. Models of this type are either difficult of impossible to build in terms of relational Kripkean semantics [40]. We conclude by introducing general first order neighborhood frames with constant domains and we offer a general completeness result for the entire family of classical first order modal systems in terms of them, circumventing some well-known problems of propositional and first order neighborhood semantics (mainly the fact that many classical modal logics are incomplete with respect to an unmodified version of either neighborhood or relational frames). We argue that the semantical program that thus arises offers the first complete semantic unification of the family of classical first order modal logics.

Unrestricted Hybridization of Oligonucleotides to Structure-Free DNA

The existence of secondary structure in long single-stranded DNA and RNA is a serious obstacle to the practical use of short oligonucleotide probes (<20-mers). Here, we show that replication of a highly structured DNA in the presence of a unique set of dNTP analogues leads to synthesis of daughter DNA with a significantly reduced level of secondary structure. This replicated DNA, composed of 2-aminoadenine, 2-thiothymine, 7-deazaguanine, and cytosine bases, was readily accessible to tiled 8-mer LNA and 15-mer DNA probes, whereas an unmodified version of the same DNA was inaccessible. Importantly, while the base analogues enhanced probe-target stability, they did not significantly reduce the specificity of base pairing. The availability of structure-free DNA targets should facilitate the use of short oligonucleotide probes and promote development of generic oligonucleotide microarrays.

Reduced Incidence of Slowly Progressive Heymann Nephritis in Rats Immunized With a Modified Vaccination Technique

A slowly progressive Heymann nephritis (SPHN) was induced in three groups of rats by weekly injections of a chemically modified renal tubular antigen in an aqueous medium. A control group of rats received the chemically unmodified version of the antigen in an aqueous solution. One group of SPHN rats were pre- and post-treated with weekly injections of IC made up of rKF3 and rarKF3 IgM antibody at antigen excess (MIC) (immune complexes [ICs] containing sonicated ultracentrifuged [u/c] rat kidney fraction 3 [rKF3] antigen and IgM antibodies specific against the antigen, at slight antigen excess). One group of SPHN rats were post-treated with MIC 3 weeks after the induction of the disease and one group of SPHN animals received no treatment. The control group of rats received pre- and post-treatment with sonicated u/c rKF3. The incidence of immune-complex glomerulonephritis (ICGN) in the untreated SPHN rats was 87%, in the pre- and post-treated animals 13%, and in the post-treated-only rats 20%. Rats receiving sonicated ultracentrifuged rKF3 antigen did not develop ICGN. The present experiment demonstrates that the development of SPHN can be not only prevented but also effectively terminated by our newly developed modified vaccination technique.