Publications by authors named "John Robinson"

FcRn, a nonclassical MHC-I protein bound to beta 2-microglobulin (beta 2m), diverts IgG and albumin from an intracellular degradative fate, prolonging the half-lives of both. While knockout mouse strains lacking either FcRn-alpha-chain (AK) or beta 2m (BK) show much shorter half-lives of IgG and albumin than normal mice, the plasma IgG half-life in the BK and AK strains is different, being shorter in the BK strain. Since beta 2m does not affect the IgG production rate, we tested whether an additional beta 2m-associated mechanism protects IgG from catabolism.

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Objective: To assess the ability of regression tree boosting to risk-adjust health care cost predictions, using diagnostic groups and demographic variables as inputs. Systems for risk-adjusting health care cost, described in the literature, have consistently employed deterministic models to account for interactions among diagnostic groups, simplifying their statistical representation, but sacrificing potentially useful information. An alternative is to use a statistical learning algorithm such as regression tree boosting that systematically searches the data for consequential interactions, which it automatically incorporates into a risk-adjustment model that is customized to the population under study.

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Receiving a diagnosis of and treatment for prostate cancer often results in significant physical side-effects and associated psychosocial stressors that can interfere with the experience of sexual intimacy for couples. Despite the fact that prostate cancer affects mainly older men, the maintenance of sexual intimacy is an important issue to consider, as the majority of older adults continue to value, engage in, and enjoy sexual activity throughout their lives. While the current research identifies the challenges that many men face, little is known about the strategies that couples use to successfully maintain sexual intimacy after prostate cancer treatment.

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Of 4,268 wild ducks sampled in Canada in 2005, real-time reverse transcriptase-PCR detected influenza A matrix protein (M1) gene sequence in 37% and H5 gene sequence in 5%. Mallards accounted for 61% of samples, 73% of M1-positive ducks, and 90% of H5-positive ducks. Ducks hatched in 2005 accounted for 80% of the sample.

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The arbitrary division between antiphospholipid antibody syndrome and secondary antiphospholipid antibody syndrome has not proven useful. Antiphospholipid antibodies in the absence of antiphospholipid antibody syndrome often occur as epiphenomena in many autoimmune diseases. They are very common in systemic lupus erythematosus.

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OxyB catalyzes the first oxidative phenol coupling reaction in vancomycin biosynthesis. OxyB is a P450 hemoprotein whose activity is strictly dependent upon the presence of molecular oxygen. Here, it was shown that label from (18)O(2) is not incorporated into the monocyclic product during catalysis by OxyB.

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Current toxicogenomic approaches generate transcriptional profiles that can identify functional gene expression signatures of environmental toxicants. However, the intricate processes governing transcription are overlaid with a complex set of molecular instructions involving epigenetic modifications. These commands regulate both gene expression and chromatin organization through coordinated sets of histone modifications and heritable DNA methylation patterns.

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Objectives: Peptides delivered on the surface of influenza virosomes have been shown to induce solid humoral immune responses in experimental animals. High titers of peptide-specific antibodies were also induced in a phase 1a clinical trial in volunteers immunized with virosomal formulations of two peptides derived from the circumsporozoite protein (CSP) and the apical membrane antigen 1 (AMA-1) of Plasmodium falciparum. The main objective of this study was to perform a detailed immunological and functional analysis of the CSP-specific antibodies elicited in this phase 1a trial.

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The bone marrow microenvironment provides a unique opportunity in vivo to assess the role of genes in bone remodeling. The objective of this study was to determine whether Runx2 expression is regulated by rhBMP-2 in vivo and to examine the effect of Runx2 overexpression on bone in vivo. In the in vivo calvaria model we used, rhBMP-2 induced Runx2 protein expression in periosteal cells while in vitro, adenovirus-mediated Runx2 overexpression induced mineralization in mesenchymal stem cells.

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The human amnion is a major intrauterine source of prostaglandin (PG) E(2), a potent mediator of uterine contractions and cervical ripening. During parturition, inflammatory cytokines promote PGE(2) production through increased prostaglandin-endoperoxide synthase-2 (PTGS2, also known as cyclooxygenase-2) expression. This is mediated, in part, through activation of the transcription factor nuclear factor kappa B (NFkappaB).

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Purpose: To monitor early- and late-stage arterial remodeling following low-level cholesterol (CH) feeding in rabbits using a standardized MRI protocol.

Materials And Methods: New Zealand White rabbits were fed a CH diet (0.25% w/w) (n = 15) or normal chow (n = 6) and imaged either at 0, 2, 6, 8, and 11 months ("early-stage") or 12, 14, 16, 18, and 20 months ("late-stage").

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The turn-forming D-Pro-L-Pro template has been frequently used to promote regular beta-hairpin conformations in cyclic protein epitope mimetics. Here the use of three isomeric biaryl templates has been studied as alternatives to D-Pro-L-Pro in the preparation of beta-hairpin peptidomimetics. The o,o'- o,m'- and m,m'-isomers of carboxymethyl- and aminomethyl-substituted biaryl templates have been incorporated into novel macrocyclic mimics of the naturally occurring cationic antimicrobial peptide protegrin I.

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Histochemical techniques have contributed significantly to advances in placental biology and cell biology. In this mini-review, we describe recent advances in histochemical technologies and show how these technologies can profoundly improve our understanding of placenta morphological function related to health and disease. Fundamental theories and applications of five separate methods discussed here are 1) tissue-based polymerase chain reaction by laser microdissection, 2) a novel antigen retrieval method using citraconic anhydride plus heating, 3) immunohistochemical detection of Lewis-related antigen expression and galectin-1 binding in the human placenta, 4) confocal microscopy analysis of IgG transport in placental trophoblasts, and 5) high-resolution immunofluorescence and correlative microscopy using ultrathin cryosections in placental research.

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Serine repeat antigen-5 (SERA5) is a candidate antigen for inclusion into a malaria subunit vaccine. During merozoite release and reinvasion the 120 kDa SERA5 precursor protein (P120) is processed, and a complex consisting of an N-terminal 47 kDa (P47) and a C-terminal 18kDa (P18) processing product associates with the surface of merozoites. This complex is thought to be involved in merozoite invasion of and/or egress from host erythrocytes.

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We have investigated the biochemical and functional properties of toposome, a major protein component of sea urchin eggs and embryos. Atomic force microscopy was utilized to demonstrate that a Ca(2+)-driven change in secondary structure facilitated toposome binding to a lipid bilayer. Thermal denaturation studies showed that toposome was dependent upon calcium in a manner paralleling the effect of this cation on secondary and tertiary structure.

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The Abbott RealTime HIV-1 assay is an automated test for monitoring HIV-1 viral load in plasma samples. The assay uses reverse transcription polymerase chain reaction (RT-PCR) technology with homogeneous real-time fluorescent detection. Automated sample preparation is performed on the m2000sp instrument where RNA is isolated using magnetic microparticle technology and dispensed to a PCR tray together with the amplification reagents.

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Real-time PCR assays have recently been developed for diagnostic and research purposes. Signal generation in real-time PCR is achieved with probe designs that usually depend on exonuclease activity of DNA polymerase (e.g.

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Here, we investigated if TAR-DNA-binding protein-43 (TDP-43), the disease protein in frontotemporal lobar degeneration and ubiquitin inclusions with or without motor neuron disease as well as amyotrophic lateral sclerosis, also formed inclusions in Lewy body (LB) disorders including Parkinson's disease (PD) without or with dementia (PDD), and dementia with LBs (DLB) alone or in association with Alzheimer's disease (AD). Immunohistochemical analyses of TDP-43 in clinically well characterized and pathologically confirmed cases of DLB + AD, PD and PDD demonstrated TDP-43 pathology in the following percentage of cases: DLB + AD = 25/80 (31.3%); PD = 5/69 (7.

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Quantitative PCR (QPCR) methods targeting the 18S rDNA gene (DNA QPCR) and cathepsin L mRNA (RNA QPCR) from Kudoa thyrsites (Gilchrist) were developed and compared with histology for determination of K. thyrsites infection levels in Atlantic salmon Salmo salar L. Both QPCR tests were specific, reproducible and sensitive down to 3 copies.

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