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801.
Jayna Raghwani Rebecca Rose Isabelle Sheridan Philippe Lemey Marc A. Suchard Teresa Santantonio Patrizia Farci Paul Klenerman Oliver G. Pybus 《PLoS pathogens》2016,12(9)
The treatment of HCV infection has seen significant progress, particularly since the approval of new direct-acting antiviral drugs. However these clinical achievements have been made despite an incomplete understanding of HCV replication and within-host evolution, especially compared with HIV-1. Here, we undertake a comprehensive analysis of HCV within-host evolution during chronic infection by investigating over 4000 viral sequences sampled longitudinally from 15 HCV-infected patients. We compare our HCV results to those from a well-studied HIV-1 cohort, revealing key differences in the evolutionary behaviour of these two chronic-infecting pathogens. Notably, we find an exceptional level of heterogeneity in the molecular evolution of HCV, both within and among infected individuals. Furthermore, these patterns are associated with the long-term maintenance of viral lineages within patients, which fluctuate in relative frequency in peripheral blood. Together, our findings demonstrate that HCV replication behavior is complex and likely comprises multiple viral subpopulations with distinct evolutionary dynamics. The presence of a structured viral population can explain apparent paradoxes in chronic HCV infection, such as rapid fluctuations in viral diversity and the reappearance of viral strains years after their initial detection. 相似文献
802.
803.
Morbini Patrizia Manzo Antonio Caporali Roberto Epis Oscar Villa Chiara Tinelli Carmine Solcia Enrico Montecucco Carlomaurizio 《Arthritis research & therapy》2005,7(2):1-6
The recently observed low reproducibility of focus score (FS) assessment at different section depths in a series of single minor salivary gland biopsies highlighted the need for a standardized protocol of extensive histopathological examination of such biopsies in Sjögren's syndrome. For this purpose, a cumulative focus score (cFS) was evaluated on three slides cut at 200-μm intervals from each of a series of 120 salivary biopsies. The cFS was substituted for the baseline FS in the American–European Consensus Group (AECG) criteria set for Sjögren's syndrome classification, and then test specificity and sensitivity were assessed against clinical patient re-evaluation. Test performances of the AECG classification with the original FS and the score obtained after multilevel examination were statistically compared using receiver operating characteristic (ROC) curve analysis. The diagnostic performance of AECG classification significantly improved when the cFS was entered in the AECG classification; the improvement was mostly due to increased specificity in biopsies with a baseline FS ≥ 1 but <2. The assessment of a cFS obtained at three different section levels on minor salivary gland biopsies can be useful especially in biopsies with baseline FSs between 1 and 2. 相似文献
804.
805.
806.
Silvana Galderisi Alessandro Rossi Paola Rocca Alessandro Bertolino Armida Mucci Paola Bucci Paola Rucci Dino Gibertoni Eugenio Aguglia Mario Amore Antonello Bellomo Massimo Biondi Roberto Brugnoli Liliana Dell'Osso Diana De Ronchi Gabriella Di Emidio Massimo Di Giannantonio Andrea Fagiolini Carlo Marchesi Palmiero Monteleone Lucio Oldani Federica Pinna Rita Roncone Emilio Sacchetti Paolo Santonastaso Alberto Siracusano Antonio Vita Patrizia Zeppegno Mario Maj Italian Network For Research on Psychoses 《World psychiatry》2014,13(3):275-287
In people suffering from schizophrenia, major areas of everyday life are impaired, including independent living, productive activities and social relationships. Enhanced understanding of factors that hinder real‐life functioning is vital for treatments to translate into more positive outcomes. The goal of the present study was to identify predictors of real‐life functioning in people with schizophrenia, and to assess their relative contribution. Based on previous literature and clinical experience, several factors were selected and grouped into three categories: illness‐related variables, personal resources and context‐related factors. Some of these variables were never investigated before in relationship with real‐life functioning. In 921 patients with schizophrenia living in the community, we found that variables relevant to the disease, personal resources and social context explain 53.8% of real‐life functioning variance in a structural equation model. Neurocognition exhibited the strongest, though indirect, association with real‐life functioning. Positive symptoms and disorganization, as well as avolition, proved to have significant direct and indirect effects, while depression had no significant association and poor emotional expression was only indirectly and weakly related to real‐life functioning. Availability of a disability pension and access to social and family incentives also showed a significant direct association with functioning. Social cognition, functional capacity, resilience, internalized stigma and engagement with mental health services served as mediators. The observed complex associations among investigated predictors, mediators and real‐life functioning strongly suggest that integrated and personalized programs should be provided as standard treatment to people with schizophrenia. 相似文献
807.
Morbini P Manzo A Caporali R Epis O Villa C Tinelli C Solcia E Montecucco C 《Arthritis research & therapy》2005,7(2):R343-R348
The recently observed low reproducibility of focus score (FS) assessment at different section depths in a series of single minor salivary gland biopsies highlighted the need for a standardized protocol of extensive histopathological examination of such biopsies in Sjogren's syndrome. For this purpose, a cumulative focus score (cFS) was evaluated on three slides cut at 200-mum intervals from each of a series of 120 salivary biopsies. The cFS was substituted for the baseline FS in the American-European Consensus Group (AECG) criteria set for Sjogren's syndrome classification, and then test specificity and sensitivity were assessed against clinical patient re-evaluation. Test performances of the AECG classification with the original FS and the score obtained after multilevel examination were statistically compared using receiver operating characteristic (ROC) curve analysis. The diagnostic performance of AECG classification significantly improved when the cFS was entered in the AECG classification; the improvement was mostly due to increased specificity in biopsies with a baseline FS >or= 1 but <2. The assessment of a cFS obtained at three different section levels on minor salivary gland biopsies can be useful especially in biopsies with baseline FSs between 1 and 2. 相似文献
808.
Patrizia Campolongo Patrizia Ratano Maria Teresa Ciotti Fulvio Florenzano Stefania Lucia Nori Roberta Marolda Maura Palmery Anna Maria Rinaldi Cristina Zona Roberta Possenti Pietro Calissano Cinzia Severini 《PloS one》2013,8(11)
Reduced levels of Substance P (SP), an endogenous neuropeptide endowed with neuroprotective and anti-apoptotic properties, have been found in brain and spinal fluid of Alzheimer''s disease (AD) patients. Potassium (K+) channel dysfunction is implicated in AD development and the amyloid-β (Aβ)-induced up-regulation of voltage-gated potassium channel subunits could be considered a significant step in Aβ brain toxicity. The aim of this study was to evaluate whether SP could reduce, in vivo, Aβ-induced overexpression of Kv subunits. Rats were intracerebroventricularly infused with amyloid-β 25–35 (Aβ25–35, 20 µg) peptide. SP (50 µg/Kg, i.p.) was daily administered, for 7 days starting from the day of the surgery. Here we demonstrate that the Aβ infused rats showed impairment in cognitive performances in the Morris water maze task 4 weeks after Aβ25–35 infusion and that this impairing effect was prevented by SP administration.Kv1.4, Kv2.1 and Kv4.2 subunit levels were quantified in hippocampus and in cerebral cortex by Western blot analysis and immunofluorescence. Interestingly, SP reduced Kv1.4 levels overexpressed by Aβ, both in hippocampus and cerebral cortex.Our findings provide in vivo evidence for a neuroprotective activity of systemic administration of SP in a rat model of AD and suggest a possible mechanism underlying this effect. 相似文献
809.
Martin Tauschmann Barbara Prietl Gerlies Treiber Gregor Gorkiewicz Patrizia Kump Christoph H?genauer Thomas R. Pieber 《PloS one》2013,8(11)
The gastrointestinal immune system is involved in the development of several autoimmune-mediated diseases, including inflammatory bowel disease, multiple sclerosis, and type 1 diabetes mellitus. Alterations in T-cell populations, especially regulatory T cells (Tregs), are often evident in patients suffering from these diseases. To be able to detect changes in T-cell populations in diseased tissue, it is crucial to investigate T-cell populations in healthy individuals, and to characterize their variation among different regions of the gastrointestinal (GI) tract. While limited data exist, quantitative data on biopsies systematically drawn from various regions of the GI tract are lacking, particularly in healthy young humans. In this report, we present the first systematic assessment of how T cells—including Tregs—are distributed in the gastrointestinal mucosa throughout the GI tract of healthy young humans by means of multi-parameter FACS analysis. Gastroduodenoscopy and colonoscopy were performed on 16 healthy volunteers aged between 18 and 32. Biopsies were drawn from seven GI regions, and were used to determine the frequencies of CD8+-, CD4+- and Tregs in the gastrointestinal mucosa by means of multi-parameter FACS analysis. Our data show that there is significant variation in the baseline T-cell landscape along the healthy human gastrointestinal tract, and that mucosal T-cell analyses from a single region should not be taken as representative of the entire gastrointestinal tract. We show that certain T-cell subsets in the gastrointestinal mucosa vary significantly among regions; most notably, that Tregs are enriched in the appendiceal orifice region and the ascending colon, and that CD8pos T cells are enriched in the gastric mucosa. 相似文献
810.
Patrizia Vici Simonetta Buglioni Domenico Sergi Laura Pizzuti Luigi Di Lauro Barbara Antoniani Francesca Sperati Irene Terrenato Mariantonia Carosi Teresa Gamucci Rosanna Dattilo Monica Bartucci Cristina Vincenzoni Luciano Mariani Enrico Vizza Giuseppe Sanguineti Angiolo Gadducci Ilio Vitale Maddalena Barba Ruggero De Maria Marcella Mottolese Marcello Maugeri-Saccà 《PloS one》2016,11(3)
Cervical cancer cells commonly harbour a defective G1/S checkpoint owing to the interaction of viral oncoproteins with p53 and retinoblastoma protein. The activation of the G2/M checkpoint may thus become essential for protecting cancer cells from genotoxic insults, such as chemotherapy. In 52 cervical cancer patients treated with neoadjuvant chemotherapy, we investigated whether the levels of phosphorylated Wee1 (pWee1), a key G2/M checkpoint kinase, and γ-H2AX, a marker of DNA double-strand breaks, discriminated between patients with a pathological complete response (pCR) and those with residual disease. We also tested the association between pWee1 and phosphorylated Chk1 (pChk1), a kinase acting upstream Wee1 in the G2/M checkpoint pathway. pWee1, γ-H2AX and pChk1 were retrospectively assessed in diagnostic biopsies by immunohistochemistry. The degrees of pWee1 and pChk1 expression were defined using three different classification methods, i.e., staining intensity, Allred score, and a multiplicative score. γ-H2AX was analyzed both as continuous and categorical variable. Irrespective of the classification used, elevated levels of pWee1 and γ-H2AX were significantly associated with a lower rate of pCR. In univariate and multivariate analyses, pWee1 and γ-H2AX were both associated with reduced pCR. Internal validation conducted through a re-sampling without replacement procedure confirmed the robustness of the multivariate model. Finally, we found a significant association between pWee1 and pChk1. The message conveyed by the present analysis is that biomarkers of DNA damage and repair may predict the efficacy of neoadjuvant chemotherapy in cervical cancer. Further studies are warranted to prospectively validate these encouraging findings. 相似文献