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The distribution of counterions inside urchinlike charged copolymer micelles is investigated using Monte Carlo simulation. Each highly charged arm of the micelle is fixed in a rodlike geometry. Three different categories can be distinguished in the counterion population: ions locally condensed in the vicinity of the stretched branches, ions trapped inside the globular micelle and free ions localized outside the micelle which monitor the osmotic pressure and the long range electrostatic repulsion between micelles. Comparisons with simple Poisson–Boltzmann theories in various geometries and with small-angle x-ray scattering confirm this picture. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Purpose: The diagnosis of cytomegalovirus (CMV) anterior uveitis in immunocompetent patients requires confirmation by polymerase chain reaction (PCR) analysis and/or intraocular antibody index (AI) assay. In this study, we analyzed the different contributions of PCR and AI to CMV diagnosis by performing one single aqueous tap.Methods: A retrospective chart review was conducted of HIV-negative patients attending the Ocular Immunology Unit of Azienda Unità Sanitaria Locale - IRCCS, Reggio Emilia, Italy, from March 2015 to April 2018 with a diagnosis of hypertensive anterior granulomatous uveitis compatible with suspected CMV etiology. Diagnosis was confirmed by real-time PCR (RT-PCR) and intraocular antibody production against CMV on aqueous humor samples. Clinical features were compared to antibody titer and diagnostic delay.Results: Twenty-three patients with suspected CMV uveitis (13 males, 10 females, mean age 48 ± 16 years) were included in the analysis. AI was positive in 20/23 (87%) samples, and PCR tested positive in 9/23 (39%). By combining both tests, the sensitivity was 100%. Median diagnostic delay was 29 months (IQR 9-107). Diagnostic delay and antibody titer were significantly associated with glaucoma (r = 0.714, p < 0.0001; r = 0.476, p = 0.02, respectively).Conclusions: Our data suggest that to improve the diagnostic accuracy of CMV anterior uveitis, PCR and AI are both useful and complimentary. In our series, AI was the most sensitive diagnostic tool. One single aqueous tap is sufficient to achieve 100% sensitivity in CMV diagnosis. Early diagnosis is necessary to prevent the development of glaucoma. [ABSTRACT FROM AUTHOR]

Solutions of highly charged polyelectrolyte chains are described by a model that introduces ion condensation as a random charge along the polymer. The degree of condensation is obtained by solving the Poisson–Boltzmann equation with cylindrical geometry. Short range electrostatic attractions between the monomers via the condensed counterions of high enough valency lead to reversible chain precipitation. The range of polymer concentration over which salt-free solutions are unstable is determined, as well as the miscibility of the chains when salt is added. Redissolution at high salt concentration is due to a screening of the short range electrostatic attractions. Precipitation of chains in mixtures of movalent and multivalent salts is also studied. We find the range of salt concentration where chains precipitate. The model explains the experimental results on the precipitation of sodium and lanthanum polystyrene sulfonate solutions in presence of multivalent salts [LaCl3 and Th(NO3)4]. © 1995 American Institute of Physics. [ABSTRACT FROM AUTHOR]

HBV infection remains a leading cause of death worldwide. IFN-α inhibits viral replication in vitro and in vivo, and pegylated IFN-α is a commonly administered treatment for individuals infected with HBV. The HBV genome contains a typical IFN-stimulated response element (ISRE), but the molecular mechanisms by which IFN-α suppresses HBV replication have not been established in relevant experimental systems. Here, we show that IFN-α inhibits HBV replication by decreasing the transcription of pregenomic RNA (pgRNA) and subgenomic RNA from the HBV covalently closed circular DNA (cccDNA) minichromosome, both in cultured cells in which HBV is replicating and in mice whose livers have been repopulated with human hepatocytes and infected with HBV. Administration of IFN-α resulted in cccDNA-bound histone hypoacetylation as well as active recruitment to the cccDNA of transcriptional corepressors. IFN-α treatment also reduced binding of the STAT1 and STAT2 transcription factors to active cccDNA. The inhibitory activity of IFN-α was linked to the IRSE, as IRSE-mutant HBV transcribed less pgRNA and could not be repressed by IFN-α treatment. Our results identify a molecular mechanism whereby IFN-α mediates epigenetic repression of HBV cccDNA transcriptional activity, which may assist in the development of novel effective therapeutics. [ABSTRACT FROM AUTHOR]

The P73 gene is transcribed from two promoters, P1 and P2, that direct the expression of multiple transactivation competent (TA) and dominant negative (DN) isoforms. TAp73 transcription factors mediate cell cycle arrest and/or apoptosis in response to DNA damage and are involved in developmental processes. P73 mRNA levels increase and the P1p73 promoter is upregulated during myogenic differentiation of C2C12 skeletal muscle satellite cells. The DNp73 proteins act as trans-repressors of p53- and p73-dependent transcription, and possess both antiapoptotic and pro-proliferative potential. Here, we show that DNp73α is expressed in proliferating C2C12 myoblasts, rapidly accumulates in differentiating myocytes and remains elevated in C2C12 myotubes. By combining transactivation assays and chromatin immunoprecipitation analysis, we could show that the upregulation of the P2p73 promoter during myogenic differentiation is mediated by the coordinated recruitment and activity of MyoD and p53/p73. Abrogation of DNp73 expression by specific siRNA led to a strong potentiation of the spontaneous apoptosis of C2C12 myoblasts induced to differentiate. Finally, unlike TAp73 that contributes to DNA damage-induced apoptosis of myotubes, endogenous DNp73 mediates the relative resistance of differentiated myotubes to DNA damage. Altogether, our findings identify DNp73α as an important target in designing strategies aimed at the potentiation of the regenerative potential of skeletal satellite cells.Oncogene (2006) 25, 3606–3612. doi:10.1038/sj.onc.1209321; published online 1 May 2006 [ABSTRACT FROM AUTHOR]

The three main currently proposed approaches for understanding specific ion effects are briefly described. In some experimentally well defined and simplified situations, one can decouple ion specificity effects from all others. Small globular micelles in water/salt mixtures are one of the simple situations where specific ion effects can be distinguished: ‘hydrophobic ions’ introduced by Hofmeister in the late 19th century, also called ‘structure breaking’ or ‘salting in’ ions, which are similar to ‘soft ions’ in the classification introduced by Pearson, are more strongly adsorbed on the micellar surface than predicted by electrostatics alone. Hence, lateral repulsions between surfactants are increased, resulting in a measurable and calculable decrease of micelle size when adsorbing anions such as bromide replace non-adsorbing anions such as chloride. [Copyright &y& Elsevier]

Purpose: To analyze the referral patterns and the clinical and therapeutic features of patients diagnosed with uveitis in an Italian tertiary referral center to provide a comparison with previously published series from the same center. Methods: Retrospective retrieval of data on all new referrals to the Ocular Immunology Unit in Reggio Emilia (Italy) between November 2015 and April 2022 and comparison with previously published series from the same center. Results: Among the 1557 patients, the male-to-female ratio was 1:1.27. Anterior uveitis was the most common diagnosis (53.7%), followed by posterior (21.6%), pan- (18.5%), and intermediate (6.2%) uveitis. The most identifiable specific diagnoses were anterior herpetic uveitis (18.4%), Fuchs uveitis (12.8%), and tuberculosis (6.1%). Infectious etiologies were the most frequent (34.1%) and were more diffuse among non-Caucasian patients (p < 0.001), followed by systemic disease-associated uveitis (26.5%), and ocular-specific conditions (20%). Idiopathic uveitis accounted for 19.4% of cases. Fuchs uveitis presented the longest median diagnostic delay (21 months). Immunosuppressants were administered to 25.2% of patients. Antimetabolites, calcineurin inhibitors, and biologicals were prescribed to 18.4%, 3%, and 11.4% of cases, respectively. Compared to our previous reports, we observed a significant increase in foreign-born patients and in infectious uveitis, a decrease in idiopathic conditions, and an increasing use of non-biological and biological steroid-sparing drugs. Conclusions: The patterns of uveitis in Italy have been changing over the last 20 years, very likely due to migration flows. Diagnostic improvements and a more widespread interdisciplinary approach could reduce the incidence of idiopathic uveitis as well as diagnostic delay. [ABSTRACT FROM AUTHOR]

Imogolite and allophane are two strongly curved nanominerals. Indeed, imogolite has a tubular shape with a diameter of only 2.5 nm. Allophane is often presented as a spherical nanostructure with a diameter of about 5 nm. The mechanism explaining the strong curvature of these two nanominerals has been extensively discussed. However, whether or not these two nanomaterials are related to each other is not clear and the mechanism responsible for the selection between the two different shapes is not well established. In this article, we propose that imogolite and allophane are nanopolymorphs of the imogolite local structure and that the transition from spherical to tubular shape occurs at an early stage of the precipitation because of edge stress in proto-imogolite. This hypothesis for the shape selection is supported by the use of a nanomechanical model tuned to mimic the main characteristics of imogolite-like nanomaterials. [ABSTRACT FROM AUTHOR]

The charge structure factor of a 1-1 electrolyte solution has been measured by means of small angle neutron scattering. To this end the system was chosen so as to achieve a zero average contrast for the salt. The data are used to test the Stillinger and Lovett sum rules, and also to test the modelization of the solution structure including short range as well as Coulombic interactions. This modelization is based on the hypernetted chain integral equation and on suitable solvent-averaged pair potentials. At small values of wave number transfer, the experimental results are compared to a new approximation for the charge structure factor. [ABSTRACT FROM AUTHOR]

ApoJ/Clusterin (CLU) is a heterodimeric protein localized in the nucleus, cytoplasm or secretory organelles and involved in cell survival and neoplastic transformation. Its function in human cancer is still highly controversial. In this study, we examined the prostate of mice in which CLU has been genetically inactivated. Surprisingly, we observed transformation of the prostate epithelium in the majority of CLU knockout mice. Either PIN (prostate intraepithelial neoplasia) or differentiated carcinoma was observed in 100 and 87% of mice with homozygous or heterozygous deletion of CLU, respectively. Crossing CLU knockout with TRAMP (prostate cancer prone) mice results in a strong enhancement of metastatic spread. Finally, CLU depletion causes tumourigenesis in female TRAMP mice, which are normally cancer free. Mechanistically, deletion of CLU induces activation of nuclear factor-kB, a potentially oncogenic transcription factor important for the proliferation and survival of prostate cells. [ABSTRACT FROM AUTHOR]

Presents a correction to the article 'The Charge Structure Factor of 1-1 Electrolyte in Solution,' which appeared in the 1992 issue of the 'Journal of Chemical Physics.'