356 research outputs found

    Cyclic dipeptides produced by marine sponge-associated bacteria as quorum sensing signals.

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    Four bacterial strains belonging to the genera Vibrio, Pseudoalteromonas and Photobacterium were isolated from the marine sponges Dysidea avara and Geodia cynodium. A Bacillus strain was isolated from Ircinia variabilis. A screening of molecules involved in quorum sensing (QS) was carried out by TLC-overlay and a new "plate T-streak" test. To analyze quorum quenching (QQ), a plate T-streak was performed with Chromobacterium violaceum. Strains of Vibrio isolated from both marine sponges and a strain of Photobacterium isolated from G. cynodium, activated QS bioreporters. A strain of Pseudoalteromonas isolated from D. avara showed QQ activity. Finally, it is reported that cyclic dipeptides isolated from strains of Vibrio sp. and Bacillus sp. (isolated from D. avara and I. variabilis, respectively) were involved in the QS mechanism. The simultaneous presence of bacteria that showed contrasting responses in bioassays for QS signal molecule synthesis in marine sponges could add an interesting dimension to the signalling interactions which may be happening in sponges

    Further in vitro biological activity evaluation of amino-, thio- and ester-derivatives of avarol

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    The acetylcholinesterase inhibitory and/or antitumour activities of amino-, thio-and ester-derivatives of avarol selected were evaluated for the first time at in vitro conditions. Avarol-3',4'-dithioglycol (1) and avarol-4'-(3) mercaptopropionic acid (3) were shown to be the best inhibitors of the enzyme tested (0.50 mu g and IC50 0.05mM and 0.50 mg and IC50 0.12 mM, respectively), while 4'-tryptamine-avarone (9) and avarol-3'-(3) mercaptopropionic acid (2) exhibited the highest cytotoxicity against the human breast T-47D cancer cell line (IC50 0.66 mu g/mL and 1.25 mu g/mL, respectively). According to experimental data obtained, the sesquiterpenoid hydroquinone structure of bioactive avarol derivatives may inspire development of new pharmacologically useful substances to be used in the treatment of Alzheimer's disease and/or human breast tumour

    A New Lichen Depsidone from L Obaria Pulmonaria

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    The continuation of our phytochemical survey of Lobaria pulmonaria (L.) Hoffm. (Lobariaceae), has led to the isolation and identification of a new lichen depsidone (1) characterised by the normal analytical and spectroscopic techniques. Unlike previously isolated depsidone (2) from the same species, the compound 1 has not showed activity in the acetylcholinesterase inhibition test on Thin-layer chromatography plate

    Clinical relevance of intrahepatic hepatitis B virus DNA in HBsAg-negative HBcAb-positive patients undergoing hematopoietic stem cell transplantation for hematological malignancies.

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    Hepatitis flare-up due to hepatitis B virus (HBV) is a well-recognized complication associated with chemotherapy. Data on the clinical impact of HBV DNA in liver tissue of HB-surface antigen (sAg)-negative patients undergoing immunosuppression are scanty

    CD34 Expression in the Stromal Cells of Alveolar Adenoma

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    The alveolar adenoma of the lung is a rare benign tumor characterized by a proliferation of both the alveolar epithelial cells and the mesenchymal septal cells. Immunohistochemically, the epithelial cells stain for cytokeratin (CK) AE1AE3, CK7, thyroid transcription factor 1 (TTF1), and surfactant apoprotein confirming the derivation by the type 2 pneumocytes. The stromal cells are negative for these markers but they show focally smooth muscle and muscle-specific actin positivity. We describe two cases that showed immunohistochemically a CD34 positivity of the mesenchymal septal cells. This aspect has been previously described in a two cases report, but not emphasized by the authors as a distinctive feature of the lesion. We consider this CD34 positivity as a marker of immaturity or stemness of the lesional septal spindle cells, that could be responsible of the different phenotypic and morphological profile of the interstitial cells, that could be, therefore, considered neoplastic and not reactive

    Mineralogical and Geochemical Characterization of Asbestiform Todorokite, Birnessite, and Ranciéite, and Their host Mn-Rich Deposits from Serra D'Aiello (Southern Italy)

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    Manganese ores, especially the oxyhydroxides in their different forms, are the dominant Mn-bearing minerals that occur in marine and terrestrial environments, where they are typically found as poorly crystalline and intermixed phases. Mn oxyhydroxides have a huge range of industrial applications and are able to exert a strong control on the mobility of trace metals. This paper reports the results of a detailed study on the Mn oxyhydroxides occurring in the manganiferous deposit outcropping in the Messinian sediments from Serra D'Aiello (Southern Italy). Nine Mn samples were characterized in detail using X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC), thermogravimetry (TG), transmission electron microscopy combined with energy dispersive spectrometry (TEM/EDS), and X-ray fluorescence (XRF). The results indicated that the Mn deposit included the oxyhydroxide mineral species birnessite, todorokite, and rancièite. The size, morphology, and chemical composition of Mn oxyhydroxide samples were investigated in order to define their impact on the environment and human health. Todorokite displayed asbestiform shapes and could disperse fibers of breathable size in the air. Furthermore, since in-depth characterization of minerals within Mn deposits may be the first step toward understanding the genetic processes of manganese deposits, hypotheses about the genesis of the Mn oxyhydroxide deposits were discussed

    Transscrotal orchidopexy for palpable cryptorchid testis: follow-up and outcomes.

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    We retrospectively reviewed the results of transscrotal orchidopexy in the surgical management of palpable testis. From January 2014 to June 2017, 130 male children with a total of 140 palpable undescended testes (UDT) underwent transscrotal orchidopexy. The charts were retrospectively reviewed for demographic data, preoperative position and mobility of the testis, patency of the peritoneal vaginal duct (PVD), and post-operative complications. The resting position of the testis and its traction towards the scrotum were assessed before surgery and under anaesthesia. The mean age of the patients was 4.6 years. The position of the testis assessed at surgery was in most cases at the external inguinal ring (62.8%), at the neck of the scrotum (15.7%), in the inguinal canal (12.8%), or in an ectopic position (8,5%). A PVD was found in 66 testes (47.1%). Two surgical cases required an inguinal incision. In each patient, the postoperative course was unremarkable. The testicle at 1-year follow-up was in a scrotal position in 134 cases, but 6 patients required a second surgical intervention for re-ascent of the testis. No testicular atrophy or inguinal hernias were observed. Transscrotal orchidopexy is a simple and effective procedure for the treatment of palpable UDT. The incidence of complications is low and manageable, with rapid postoperative recovery and early resumption of normal activities

    Plasmatic microRNA levels by ddPCR as peripheral biomarkers for IDH-wild type glioblastomas: a pilot study

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    BACKGROUND: Glioblastoma (GBM) is the most frequent malignant brain tumour in adults with a dismal prognosis and peripheral biomarkers may be useful and effective in managing patients with GBM. The main aim of our study was the use of ddPCR to assess the absolute quantification of the plasmatic levels of three miRNAs as possible GBM-specific biomarkers. We focused on: miR-21-5p, an onco-miR overexpressed in blood, tumour tissue and cell cultures derived from patients affected by GBM, miR-23b-3p and miR-34a-5p, tumour suppressor miRs dysregulated in GMB. MATERIALS AND METHODS: Eight patients presenting with firstly-diagnosed IDH-wild type GBM and 10 age- and gender-matched healthy control donors (hC) have been enrolled in the study. Peripheral blood samples were collected at diagnosis and one month after surgery. Total RNA was isolated from plasma by means of miRNeasy Serum/Plasma Kit (Qiagen), according to the manufacturer’s instructions. Digital droplet PCR (ddPCR) was performed to assess the absolute quantification of each miRNA level according to the QX200 ddPCR protocol. RESULTS: The expression analysis revealed: i) different levels of each miRNA in hC: 98.74 copies/L (±123.60), 2.56 copies/L (±5.57), 0.73 copies/L (±0.85) for miR-21-5p, miR-23b-3p and miR-34a-5p, respectively; ii) a trend of downregulation of miR-21-5p and miR-23b-3p in GMB patients at diagnosis compared to hC; iii) a trend of upregulation of each miRNA in GMB patients one month after surgery compared with the levels measured at diagnosis, in particular 3.02, 6.2 and 1.7 fold increase for miR-21-5p, miR-23b-3p and miR-34a-5p, respectively. CONCLUSIONS: In this pilot study we reported higher amounts of circulating miR-21-5p, miR-23b-3p and miR-34a-5p in plasma of patients affected by IDH-wild type GBM one month after surgery compared to the levels at diagnosis

    Determination of plasmatic microRNA levels by ddPCR as peripheral biomarkers for IDH-wild type glioblastomas: a pilot study

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    BACKGROUND: Glioblastoma (GBM) is the most frequent malignant brain tumour in adults with a dismal prognosis. Peripheral biomarkers may be useful and effective in managing patients affected by GBM. The aim of our study was to analyse the plasmatic levels of three miRNAs as possible GBM-specific biomarkers. We focused on miR-21-5p – an onco-miR overexpressed in blood, tumour tissue and cell cultures derived from patients affected by GBM – miR-23b-3p – overexpressed in GBM, especially under hypoxic conditions – and miR-34a-5p – a tumour suppressor miR downregulated in tumour tissue and serum of patients with GBM. MATERIALS AND METHODS: Eight patients presenting with firstly-diagnosed IDH-wild type GBM and 10 age- and gender-matched healthy volunteers (hV) have been enrolled in the study. Peripheral blood samples were collected at diagnosis and one month after surgery. Total RNA was isolated from plasma by means of miRNeasy Serum/Plasma Kit (Qiagen), according to the manufacturer’s instructions. Digital droplet PCR (ddPCR) was performed for each miRNA according to the QX200 EvaGreen ddPCR protocol. RESULTS: The circulating concentrations of miR-21-5p were in mean 24.00 (28.44) and 72.40 (147.88) copies/L in patients with GBM at diagnosis and one month after surgery (p=0.38), respectively, compared with 98.74 copies/L ( 123.60) quantified in hV (p=0.09; p=0.69). The mean peripheral levels of miR-23b-3p were 0.49 copies/L (0.49) at diagnosis and 3.02 copies/L (6.88) one month after surgery (p=0.32) in patients with GBM, and 2.56 copies/L (5.57) in hV (p=0.31; p=0.88). Analysing plasmatic expression of miR-34a-5p, 1.11 (1.55) and 1.85 copies/L (1.87) were measured on average at diagnosis and one month after surgery in patients with GBM (p=0.41), while 0.73 copies/L (0.85) in hV (p=0.52; p=0.11). CONCLUSIONS: We preliminarily reported higher concentrations of circulating miR-21-5p, miR-23b-3p and miR-34a-5p in plasma of patients affected by IDH-wild type GBM one month after surgery compared to the levels at diagnosis

    Brain Networks and Cognitive Impairment in Parkinson's Disease

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    : Aim: The aim of the present study is to investigate the relationship between both functional connectivity and brain networks with cognitive decline, in patients with Parkinson's disease (PD). Introduction: PD phenotype is not limited to motor impairment but, rather, a wide range of non-motor disturbances can occur, with cognitive impairment being one of the most common. However, how the large-scale organization of brain activity differs in cognitively impaired patients, as opposed to cognitively preserved ones, remains poorly understood. Methods: Starting from source-reconstructed resting-state magnetoencephalography data, we applied the phase linearity measurement (PLM) to estimate functional connectivity, globally and between brain areas, in PD patients with and without cognitive impairment (respectively PD-CI and PD-NC), as compared with healthy subjects (HS). Further, using graph analysis, we characterized the alterations in brain network topology and related these, as well as the functional connectivity, to cognitive performance. Results: We found reduced global and nodal PLM in several temporal (fusiform gyrus, Heschl's gyrus, and inferior temporal gyrus), parietal (postcentral gyrus), and occipital (lingual gyrus) areas within the left hemisphere, in the gamma band, in PD-CI patients, as compared with PD-NC and HS. With regard to the global topological features, PD-CI patients, as compared with HS and PD-NC patients, showed differences in multi-frequencies bands (delta, alpha, gamma) in the Leaf fraction, Tree hierarchy (Th) (both higher in PD-CI), and Diameter (lower in PD-CI). Finally, we found statistically significant correlations between the Montreal Cognitive Assessment test and both the Diameter in delta band and the Th in the alpha band. Conclusion: Our work points to specific large-scale rearrangements that occur selectively in cognitively compromised PD patients and are correlated to cognitive impairment. Impact statement In this article, we want to test the hypothesis that the cognitive decline observed in Parkinson's disease (PD) patients may be related to specific changes of both functional connectivity and brain network topology. Specifically, starting from magnetoencephalography signals and by applying the phase linearity measurement (PLM), a connectivity metric that measures the synchronization between brain regions, we were able to highlight differences in the global and nodal PLM values in PD patients with cognitive impairment as compared with both cognitively unimpaired patients and healthy subjects. Further, using graph analysis, we analyzed alterations in brain network topology that were related to cognitive functioning
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