The adsorption of HIV-1 capsid p24 protein bearing six histidine residues (named RH24) onto well-characterized thermosensitive and cationic poly(styrene)−poly(N-isopropylacrylamide) core−shell ...particles was investigated as a function of temperature, pH, incubation time, and salinity. The maximum amount of adsorbed RH24 was observed when the temperature was above the lower critical solution temperature (LCST) of the hydrogel, whereas a negligible adsorbed amount occurred below the LCST. Adsorption isotherms were then determined above the LCST and exhibited well-defined plateaus, which were pH and ionic strength dependent. Isotherm data were tentatively discussed using the Freundlich power law, from which the standard free enthalpy of protein adsorption was estimated. The adsorption behavior of protein was mainly governed by hydrophobic interactions above the LCST; however, differences between the two latexes gave evidence that electrostatic forces also played a significant role.
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IJS, KILJ, NUK, PNG, UL, UM
Gut immune system homeostasis is crucial to overall host health. Immune disturbance at the gut level may lead to systemic and distant sites' immune dysfunction. Probiotics and prebiotics consumption ...have been shown to improve gut microbiota composition and function and enhance gut immunity. In the current study, the immunomodulatory and anti-inflammatory effects of viable and heat-inactivated forms of the novel probiotic bacterium
subsp.
(Canan SV-53), as well as the prebiotic protocatechuic acid (PCA) derived from the fermentation of blueberry juice by SV-53, were examined. To this end, female Balb/c mice received probiotic (viable or heat-inactivated), prebiotic, or a mixture of viable probiotic and prebiotic in drinking water for three weeks. To better decipher the immunomodulatory effects of biotics intake, gut microbiota, gut mucosal immunity, T helper-17 (Th17) cell-related cytokines, and epigenetic modulation of Th17 cells were studied. In mice receiving viable SV-53 and PCA, a significant increase was noted in serum IgA levels and the number of IgA-producing B cells in the ileum. A significant reduction was observed in the concentrations of proinflammatory cytokines, including interleukin (IL)-17A, IL-6, and IL-23, and expression of two proinflammatory miRNAs, miR-223 and miR425, in treated groups. In addition, heat-inactivated SV-53 exerted immunomodulatory properties by elevating the IgA concentration in the serum and reducing IL-6 and IL-23 levels in the ileum. DNA methylation analysis revealed the role of heat-inactivated SV-53 in the epigenetic regulation of genes related to Th17 and IL-17 production and function, including
,
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,
, and
. Taken together, these findings may reflect the potential role of the novel probiotic bacterium SV-53 and prebiotic PCA in improving gut immunity and homeostasis. Further studies are required to ascertain the beneficial effects of this novel bacterium in the inflammatory state.
The PacBio whole-genome sequencing of the potential probiotic strain Canan SV-53T recovered from lowbush blueberries demonstrates high homology to Rouxiella badensis but with distinct enough clusters ...to propose the name Rouxiella badensis subsp.
. The sequencing also detected the presence of two native plasmids.
Human endogenous retroviruses (HERVs) can be divided into distinct families of tens to thousands of paralogous loci. The expression of HERV elements has been detected in all tissues tested to date, ...particularly germ cells, embryonic tissues and neoplastic tissues. Hence, the study of HERV expression could represent added value in cancer diagnosis. We developed a quantitative assay combining a multiplex degenerate PCR (MD-PCR) amplification, based on the relative conservation of the pol genes, and a colorimetric Oligo Sorbent Array (OLISA®). Nine HERV families were selected and amplification primers and capture probes were designed for each family. The features required to achieve efficient amplification of most of the elements of each HERV family and balanced co-amplification of all HERV families were analyzed. We found that MD-PCR reliability, i.e. equivalence of amplification and dose-effect relationship, relied on the adjustment of three critical parameters: the primer degeneracy, the relative concentration of each primer and the total amount of primers in the amplification mixture. The analysis of tumoral versus normal tissues suggests that this assay could prove useful in tumor phenotyping.
We report on magnetoconductance measurements of metallic networks of various sizes ranging from 10 to 10(6) plaquettes, with an anisotropic aspect ratio. Both Altshuler-Aronov-Spivak h/2e periodic ...oscillations and Aharonov-Bohm h/e periodic oscillations are observed for all networks. For large samples, the amplitude of both oscillations results from the incoherent superposition of contributions of phase coherent regions. When the transverse size becomes smaller than the phase coherent length Lphi, one enters a new regime which is phase coherent (mesoscopic) along one direction and macroscopic along the other, leading to a new size dependence of the quantum oscillations.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
The human endogenous retrovirus HERV-W multicopy family includes a unique proviral locus, termed ERVWE1, which contains gag and pol pseudogenes and has retained a full-length envelope open reading ...frame (ORF). This Env protein (syncytin) is a highly fusogenic membrane glycoprotein and has been proposed to be involved in hominoid placental physiology. To track the hallmarks of natural selection acting on the ERVWE1 env gene, the pattern of substitutions and indels was analyzed within all human HERV-W elements and along the ERVWE1 orthologous loci in chimpanzee, gorilla, orangutan, and gibbon. The comparison of ERVWE1 and paralogous HERV-W copies revealed an ERVWE1-specific signature consisting of a four amino acid deletion in the intracytoplasmic tail of the glycoprotein. We show that this deletion is crucial for the envelope fusogenic activity. The comparison of the human ERVWE1 locus with its orthologs demonstrates the existence of a selective pressure to maintain the env reading frame open. Notably, the 3' part of the env gene, encoding regions required for the fusion process, is under purifying selection. The identification of selective constraints on env ERVWE1 confirms that this retroviral locus has been recruited in the hominoid lineage to become a bona fide gene.
Expression of human endogenous retroviruses (HERV) has been recurrently observed during cellular differentiation or transformation processes in both cell culture and in vivo. Quantitative approaches ...that analyze variations in HERV transcription could therefore be valuable for cancer diagnosis. We have developed a quantitative assay combining multiplex degenerate PCR (MD-PCR) and a colorimetric Oligo Sorbent Array (OLISA). Quantification of the expression of these multifamily genes relies on the optimization of the amplification primer mix, that is, the primer degeneracy, the relative concentration of each primer and the total amount of primer. Amplification products of each of the nine studied HERV families are independently and specifically detected and quantified using the OLISA microarray. This method constitutes an improvement over previous pan-retrovirus amplification-based methods, which are mainly qualitative. Furthermore, as MD-PCR/OLISA simultaneously monitors several HERV families, it challenges single-family quantitative RT-PCR. Last, the protocol below provides general rules for the design of MD-PCR applications. Once primers have been designed and optimized, the procedure can be completed in 2 days.
Retroviral envelopes are pathogenic glycoproteins which cause neuroinflammation, neurodegeneration, and endoplasmic reticulum stress responses. The human endogenous retrovirus (HERV-W) envelope ...protein, Syncytin-1, is highly expressed in CNS glia of individuals with multiple sclerosis (MS). In this study, we investigated the mechanisms by which Syncytin-1 mediated neuroimmune activation and oligodendrocytes damage. In brain tissue from individuals with MS, ASCT1, a receptor for Syncytin-1 and a neutral amino acid transporter, was selectively suppressed in astrocytes (p < 0.05). Syncytin-1 induced the expression of the endoplasmic reticulum stress sensor, old astrocyte specifically induced substance (OASIS), in cultured astrocytes, similar to findings in MS brains. Overexpression of OASIS in astrocytes increased inducible NO synthase expression but concurrently down-regulated ASCT1 (p < 0.01). Treatment of astrocytes with a NO donor enhanced expression of early growth response 1, with an ensuing reduction in ASCT1 expression (p < 0.05). Small-interfering RNA molecules targeting Syncytin-1 selectively down-regulated its expression, preventing the suppression of ASCT1 and the release of oligodendrocyte cytotoxins by astrocytes. A Syncytin-1-transgenic mouse expressing Syncytin-1 under the glial fibrillary acidic protein promoter demonstrated neuroinflammation, ASCT1 suppression, and diminished levels of myelin proteins in the corpus callosum, consistent with observations in CNS tissues from MS patients together with neurobehavioral abnormalities compared with wild-type littermates (p < 0.05). Thus, Syncytin-1 initiated an OASIS-mediated suppression of ASCT1 in astrocytes through the induction of inducible NO synthase with ensuing oligodendrocyte injury. These studies provide new insights into the role of HERV-mediated neuroinflammation and its contribution to an autoimmune disease.
The fluorescence of a resonantly driven superconducting qubit is measured in the time domain, providing a weak probe of the qubit dynamics. Prior preparation and final, single-shot measurement of the ...qubit allows us to average fluorescence records conditionally on past and future knowledge. The resulting interferences reveal purely quantum features characteristic of weak values. We demonstrate conditional averages that go beyond classical boundaries and probe directly the jump operator associated with relaxation. The experimental results are remarkably captured by a recent theory, which generalizes quantum mechanics to open quantum systems whose past and future are known.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
STUDY DESIGN.Multicenter retrospective study of 54 children.
OBJECTIVE.To describe the complication rate of the French vertical expandable prosthetic titanium rib (VEPTR) series involving patients ...treated between August 2005 and January 2012.
SUMMARY OF BACKGROUND DATA.Congenital chest wall and spine deformities in children are complex entities. Most of the affected patients have severe scoliosis often associated with a thoracic deformity. Orthopedic treatment is generally ineffective, and surgical treatment is very challenging. These patients are good candidates for VEPTR expansion thoracoplasty. The aim of this study was to evaluate the potential complications of VEPTR surgery.
METHODS.Of the 58 case files, 54 were available for analysis. The series involved 33 girls and 21 boys with a mean age of 7 years (range, 20 mo–14 yr and 2 mo) at primary VEPTR surgery. During the follow-up period, several complications occurred.
RESULTS.Mean follow-up was 22.5 months (range, 6–64 mo). In total, 184 procedures were performed, including 56 VEPTR implantations, 98 expansions, and 30 nonscheduled procedures for different types of complicationsmechanical complications (i.e., fracture, device migration), device-related and infectious complications, neurological disorders, spine statics disturbances. Altogether, there were 74 complications in 54 patientsa complication rate of 137% per patient and 40% per surgery. Comparison of the complications in this series with those reported in the literature led the authors to suggest solutions that should help decrease their incidence.
CONCLUSION.The complication rate is consistent with that reported in the literature. Correct determination of the levels to be instrumented, preoperative improvement of nutritional status, and better evaluation of the preoperative and postoperative respiratory function are important factors in minimizing the potential complications of a technique that is used in weak patients with complex deformities.Level of Evidence4
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