2,326 research outputs found

    Involvement of suppressive B-lymphocytes in the mechanism of tolerogenic dendritic cell reversal of type 1 diabetes in NOD mice

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    The objective of the study was to identify immune cell populations, in addition to Foxp3+ T-regulatory cells, that participate in the mechanisms of action of tolerogenic dendritic cells shown to prevent and reverse type 1 diabetes in the Non-Obese Diabetic (NOD) mouse strain. Co-culture experiments using tolerogenic dendritic cells and B-cells from NOD as well as transgenic interleukin-10 promoter-reporter mice along with transfer of tolerogenic dendritic cells and CD19+ B-cells into NOD and transgenic mice, showed that these dendritic cells increased the frequency and numbers of interleukin-10-expressing B-cells in vitro and in vivo. The expansion of these cells was a consequence of both the proliferation of preexisting interleukin-10-expressing B-lymphocytes and the conversion of CD19+ B-lymphcytes into interleukin-10-expressing cells. The tolerogenic dendritic cells did not affect the suppressive activity of these B-cells. Furthermore, we discovered that the suppressive murine B-lymphocytes expressed receptors for retinoic acid which is produced by the tolerogenic dendritic cells. These data assist in identifying the nature of the B-cell population increased in response to the tolerogenic dendritic cells in a clinical trial and also validate very recent findings demonstrating a mechanistic link between human tolerogenic dendritic cells and immunosuppressive regulatory B-cells. © 2014 Di Caro et al

    Phosphatidylinositol-3-kinase activity during in vitro dendritic cell generation determines suppressive or stimulatory capacity.

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    Modulating PI3K at different stages of dendritic cells (DC) generation could be a novel means to balance the generation of immunosuppressive versus immunostimulatory DC. We show that PI3K inhibition during mouse DC generation in vitro results in cells that are potently immunosuppressive and characteristic of CD8alpha- CD11c+ CD11b+ DC. These DC exhibited low surface class I and class II MHC, CD40, and CD86 and did not produce TNF-alpha. In allogeneic MLR, these DC were suppressive. Although in these mixed cultures, there was no increase in the frequency of CD4+ CD25+ Foxp3+ cells, the Foxp3 content on a per cell basis was significantly increased. Sustained TLR9 signaling in the presence of PI3K inhibition during DC generation overrode the cells' suppressive phenotype

    Improvement of resveratrol permeation through sublingual mucosa: Chemical permeation enhancers versus spray drying technique to obtain fast-disintegrating sublingual mini-tablets

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    Resveratrol (RSV) is a natural polyphenol with several interesting broad-spectrum pharmacological properties. However, it is characterized by poor oral bioavailability, extensive first-pass effect metabolism and low stability. Indeed, RSV could benefit from the advantage of the sublingual route of administration. In this view, RSV attitudes to crossing the porcine sublingual mucosa were evaluated and promoted both by six different chemical permeation enhancers (CPEs) as well as by preparing four innovative fast-disintegrating sublingual mini-tablets by spray drying followed by direct compression. Since RSV by itself exhibits a low permeation aptitude, this could be significantly enhanced by the use of CPEs as well as by embedding RSV in a spray-dried powder to be compressed in order to prepare fast-disintegrating mini-tablets. The most promising observed CPEs (menthol, lysine and urea) were then inserted into the most promising spray-dried excipients’ compositions (RSV-B and RSV-C), thus preparing CPE-loaded mini-tablets. However, this procedure leads to unsatisfactory results which preclude the possibility of merging the two proposed approaches. Finally, the best spray-dried composition (RSV-B) was further evaluated by SEM, FTIR, XRD and disintegration as well as dissolution behavior to prove its effectiveness as a sublingual fast-disintegrating formulation

    p53-Mediated downregulation of H ferritin promoter transcriptional efficiency via NF-Y

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    The tumor suppressor protein p53 triggers many of the cellular responses to DNA damage by regulating the transcription of a series of downstream target genes. p53 acts on the promoter of the target genes by interacting with the trimeric transcription factor NF-Y. H ferritin promoter activity is tightly dependent on a multiprotein complex called Bbf; on this complex NF-Y plays a major role. The aim of this work was to study the modulation of H ferritin expression levels by p53. CAT reporter assays indicate that: (i) p53 overexpression strongly downregulates the transcriptional efficiency driven by an H ferritin promoter construct containing only the NF-Y recognition sequence and that the phenomenon is reverted by p53 siRNA; (ii) the p53 C-terminal region is sufficient to elicitate this regulation and that a correct C-terminal acetylation is also required. The H ferritin promoter displays no p53-binding sites; chromatin immunoprecipitation assays indicate that p53 is recruited on this promoter by NF-Y. The p53–NF-Y interaction does not alter the NF-Y DNA-binding ability as indicated by electrophoretic mobility shift assay (EMSA) analysis. These results demonstrate that the gene coding for the H ferritin protein belongs to the family of p53-regulated genes, therefore adding a new level of complexity to the regulation of the H ferritin transcription and delineate a role for this protein in a series of cellular events triggered by p53 activation

    Phylogenetic analysis of West Nile virus isolates, Italy, 2008-2009.

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    To determine the lineage of West Nile virus that caused outbreaks in Italy in 2008 and 2009, several West Nile virus strains were isolated from human specimens and sequenced. On the basis of phylogenetic analyses, the strains isolated constitute a distinct group within the western Mediterranean cluster

    Hypophosphataemia after intravenous iron therapy with ferric carboxymaltose—Real world experience from a tertiary centre in the UK

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    Background: Iron deficiency is the most common global cause of anaemia. Intravenous (IV) iron is used to correct iron deficiency anaemia (IDA) where oral iron cannot be used. Despite being effective, certain IV iron formulations cause significant hypophosphataemia. However, current knowledge on the clinical consequences of IV iron‐induced hypophosphataemia is broadly anecdotal or limited to isolated case reports. / Aims: To retrospectively examine the incidence and potential clinical consequences of hypophosphataemia post‐IV ferric carboxymaltose (FCM) in hospitalised patients with IDA (mixed aetiology). / Methods: Data were collected for 162 patients, who received a total of 169 FCM courses during a 2‐year audit period. Outcomes included incidence of moderate/severe hypophosphataemia (serum phosphate <0.65 mmol/L) ≤90 days post‐FCM, changes in alkaline phosphatase, need for phosphate replacement, and length of hospital stay. / Results: The incidence of moderate/severe hypophosphataemia post‐FCM was 33.7%; within this group the rate of severe hypophosphataemia (serum phosphate ≤0.32 mmol/L) was 8.8%. Moderate/severe hypophosphataemia persisted, with 35% of patients having a serum phosphate of <0.65 mmol/L for ≤90 days at the last measurement after IV FCM. Intervention with IV phosphate—an average of 4.4 infusions per person—was required in 29.8% of cases with moderate/severe hypophosphataemia. FCM‐induced moderate/severe hypophosphataemia was associated with a significantly longer hospital stay (P < 0.0035). / Conclusions: Moderate/severe hypophosphataemia is a frequent adverse drug reaction with FCM. In our study, FCM‐induced moderate/severe hypophosphataemia was also persistent, often required treatment, and was associated with longer hospital stay

    Lipid nanocarriers-loaded nanocomposite as a suitable platform to release antibacterial and antioxidant agents for immediate dental implant placement restorative treatment

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    Immediate implant placement is a single-stage restorative approach for missing teeth widely used to overcome the ridge remodeling process occurring after dental extractions. The success of this procedure relies on opportune osseointegration in the surrounding tissues. To support this process, a multifunctional nanocomposite, to be applied in the fresh post-extraction socket, was here designed, prepared, and characterized. This formulation consists of quercetin (QRC)-loaded nanostructured lipid carriers (NLCs) entrapped in a chitosan-based solid matrix containing ciprofloxacin (CPX). QRC-NLCs were prepared by homogenization followed by high-frequency sonication, and thereafter this dispersion was trapped in a chitosan-based CPX-loaded gel, obtaining the nanocomposite powder (BioQ-CPX) by lyophilization. BioQ-CPX displayed desirable properties such as high porosity (94.1 ± 0.5%), drug amounts (2.1% QRC and 3.5% CPX). and low swelling index (100%). Moreover, the mechanism of drug release from BioQ-CPX and their ability to be accumulated in the target tissue were in vitro and ex vivo elucidated, also by applying mathematical models. When trapped into the nanocomposite, QRC stressed under UV light exposure (50 W) was shown to maintain its antioxidant power, and CPX and QRC under natural light were stable over nine months. Finally, both the measured antioxidant power and the antimicrobial and antibiofilm properties on Staphylococcus aureus demonstrated that BioQ-CPX could be a promising platform to support the single-stage dental restorative treatment

    First human case of West Nile virus neuroinvasive infection in Italy, September 2008 - case report.

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    On 20 September 2008, the laboratory of the Regional Reference Centre for Microbiological Emergencies (Centro di Riferimento Regionale per le Emergenze Microbiologiche, CRREM) in Bologna, reported the detection of specific IgM and IgG antibodies against West Nile virus (WNV) in the serum of a female patient in her eighties who lived in a rural area between Ferrara and Bologna, Italy

    Modulation of pain sensitivity by chronic consumption of highly palatable food followed by abstinence: emerging role of fatty acid amide hydrolase

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    There is a strong relationship between palatable diet and pain sensitivity, and the cannabinoid and opioid systems might play an important role in this correlation. The palatable diet used in many animal models of obesity is the cafeteria (CAF) diet, based on human food with high sugar, salt, and fat content. In this study, we investigated whether long-term exposure to a CAF diet could modify pain sensitivity and explored the role of the cannabinergic system in this modification. Male Sprague–Dawley rats were divided into two groups: one fed with standard chow only (CO) and the other with extended access (EA) to a CAF diet. Hot plate and tail flick tests were used to evaluate pain sensitivity. At the end of a 40-day CAF exposure, EA rats showed a significant increase in the pain threshold compared to CO rats, finding probably due to up-regulation of CB1 and mu-opioid receptors. Instead, during abstinence from palatable foods, EA animals showed a significant increase in pain sensibility, which was ameliorated by repeated treatment with a fatty acid amide hydrolase inhibitor, PF-3845 (10 mg/kg, intraperitoneally), every other day for 28 days. Ex vivo analysis of the brains of these rats clearly showed that this effect was mediated by mu-opioid receptors, which were up-regulated following repeated treatment of PF-3845. Our data add to the knowledge about changes in pain perception in obese subjects, revealing a key role of CB1 and mu-opioid receptors and their possible pharmacological crosstalk and reinforcing the need to consider this modulation in planning effective pain management for obese patients
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