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991.
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993.
Quan Yuan Liu-Wei Song Daniela Cavallone Francesco Moriconi Beatrice Cherubini Piero Colombatto Filippo Oliveri Barbara Agata Coco Gabriele Ricco Ferruccio Bonino James Wai Kuo Shih Ning-Shao Xia Maurizia Rossana Brunetto 《PloS one》2015,10(6)
Non invasive immunologic markers of virus-induced liver disease are unmet needs. We tested the clinical significance of quantitative total and IgM-anti-HBc in well characterized chronic-HBsAg-carriers. Sera (212) were obtained from 111 HBsAg-carriers followed-up for 52 months (28-216) during different phases of chronic-HBV-genotype-D-infection: 10 HBeAg-positive, 25 inactive-carriers (HBV-DNA≤2000IU/ml, ALT<30U/L), 66 HBeAg-negative-CHB-patients and 10 with HDV-super-infection. In 35 patients treated with Peg-IFN±nucleos(t)ide-analogues (NUCs) sera were obtained at baseline, end-of-therapy and week-24-off-therapy and in 22 treated with NUCs (for 60 months, 42-134m) at baseline and end-of-follow-up. HBsAg and IgM-anti-HBc were measured by Architect-assays (Abbott, USA); total-anti-HBc by double-antigen-sandwich-immune-assay (Wantai, China); HBV-DNA by COBAS-TaqMan (Roche, Germany). Total-anti-HBc were detectable in all sera with lower levels in HBsAg-carriers without CHB (immune-tolerant, inactive and HDV-superinfected, median 3.26, range 2.26-4.49 Log10 IU/ml) versus untreated-CHB (median 4.68, range 2.76-5.54 Log10 IU/ml), p<0.0001. IgM-anti-HBc positive using the chronic-hepatitis-cut-off" (0.130-S/CO) were positive in 102 of 212 sera (48.1%). Overall total-anti-HBc and IgM-anti-HBc correlated significantly (p<0.001, r=0.417). Total-anti-HBc declined significantly in CHB patients with response to Peg-IFN (p<0.001) and in NUC-treated patients (p<0.001); the lowest levels (median 2.68, range 2.12-3.08 Log10 IU/ml) were found in long-term responders who cleared HBsAg subsequently. During spontaneous and therapy-induced fluctuations of CHB (remissions and reactivations) total- and IgM-anti-HBc correlated with ALT (p<0.001, r=0.351 and p=0.008, r=0.185 respectively). Total-anti-HBc qualifies as a useful marker of HBV-induced-liver-disease that might help to discriminate major phases of chronic HBV infection and to predict sustained response to antivirals. 相似文献
994.
Michela Sali Danilo Buonsenso Delia Goletti Pamela D’Alfonso Antonella Zumbo Giovanni Fadda Maurizio Sanguinetti Giovanni Delogu Piero Valentini 《PloS one》2015,10(10)
ObjectivesTo evaluate the accuracy of the QuantiFERON-TB Gold assay (QFT-IT) in children with suspected active or latent TB infection (LTBI).MethodsA retrospective study was conducted on 621 children (0–14 years old) evaluated for TB infection or disease. Following clinical assessment, children were tested with the QFT-IT assay.ResultsAmong the 140 active TB suspects, we identified 19 cases of active disease. The overall sensitivity for active TB was 87.5%, ranging from 62.5% in children 25–36 months old to 100% in children older than 49 months. The overall specificity for active TB was 93.6%. Among the 481 children tested for LTBI screening, 38 scored positive and all but 2 had at least one risk factor for TB infection. Among the 26 children with indeterminate results, bacterial, viral or fungal pneumonia were later diagnosed in 11 (42.3%) cases and non-TB related extra-pulmonary infections in 12 (46.1%).ConclusionsOur results indicate that the children''s response to QFT-IT associates to active TB and risk factors for LTBI. Moreover, we show that mitogen response is also found in children of 1 year of age, providing support for QFT-IT use also in young children. 相似文献
995.
David Q.‐H. Wang Maria Svelto Piero Portincasa 《Journal of cellular and molecular medicine》2015,19(2):265-282
Statins competitively inhibit hepatic 3‐hydroxy‐3‐methylglutaryl‐coenzyme A reductase, resulting in reduced plasma total and low‐density lipoprotein cholesterol levels. Recently, it has been shown that statins exert additional ‘pleiotropic’ effects by increasing expression levels of the membrane water channels aquaporin 2 (AQP2). AQP2 is localized mainly in the kidney and plays a critical role in determining cellular water content. This additional effect is independent of cholesterol homoeostasis, and depends on depletion of mevalonate‐derived intermediates of sterol synthetic pathways, i.e. farnesylpyrophosphate and geranylgeranylpyrophosphate. By up‐regulating the expression levels of AQP2, statins increase water reabsorption by the kidney, thus opening up a new avenue in treating patients with nephrogenic diabetes insipidus (NDI), a hereditary disease that yet lacks high‐powered and limited side effects therapy. Aspects related to water balance determined by AQP2 in the kidney, as well as standard and novel therapeutic strategies of NDI are discussed. 相似文献
996.
Franz Essl Bernd Lenzner Sven Bacher Sarah Bailey Cesar Capinha Curtis Daehler Stefan Dullinger Piero Genovesi Cang Hui Philip E. Hulme Jonathan M. Jeschke Stelios Katsanevakis Ingolf Kühn Brian Leung Andrew Liebhold Chunlong Liu Hugh J. MacIsaac Laura A. Meyerson Martin A. Nuez Aníbal Pauchard Petr Pyek Wolfgang Rabitsch David M. Richardson Helen E. Roy Gregory M. Ruiz James C. Russell Nathan J. Sanders Dov F. Sax Riccardo Scalera Hanno Seebens Michael Springborn Anna Turbelin Mark van Kleunen Betsy von Holle Marten Winter Rafael D. Zenni Brady J. Mattsson Nuria Roura‐Pascual 《Global Change Biology》2020,26(9):4880-4893
Understanding the likely future impacts of biological invasions is crucial yet highly challenging given the multiple relevant environmental, socio‐economic and societal contexts and drivers. In the absence of quantitative models, methods based on expert knowledge are the best option for assessing future invasion trajectories. Here, we present an expert assessment of the drivers of potential alien species impacts under contrasting scenarios and socioecological contexts through the mid‐21st century. Based on responses from 36 experts in biological invasions, moderate (20%–30%) increases in invasions, compared to the current conditions, are expected to cause major impacts on biodiversity in most socioecological contexts. Three main drivers of biological invasions—transport, climate change and socio‐economic change—were predicted to significantly affect future impacts of alien species on biodiversity even under a best‐case scenario. Other drivers (e.g. human demography and migration in tropical and subtropical regions) were also of high importance in specific global contexts (e.g. for individual taxonomic groups or biomes). We show that some best‐case scenarios can substantially reduce potential future impacts of biological invasions. However, rapid and comprehensive actions are necessary to use this potential and achieve the goals of the Post‐2020 Framework of the Convention on Biological Diversity. 相似文献
997.
Betti M Minelli A Ambrogini P Ciuffoli S Viola V Galli F Canonico B Lattanzi D Colombo E Sestili P Cuppini R 《Free radical research》2011,45(10):1136-1142
Vitamin E (as α-tocopherol, α-T) is proposed to alleviate glia-mediated inflammation in neurological diseases, but such a role in epilepsy is still elusive. This study investigated the effect of α-T supplementation on glial activation, neuronal cell death and oxidative stress of rat brain exposed to kainate-induced seizures. Animals were fed for 2 weeks with a α-T-enriched diet (estimated intake of 750 mg/kg/day) before undergoing status epilepticus. Compliance to supplementation was demonstrated by the remarkable increase in brain α-T. Four days after seizure, brain α-T returned to baseline and lipid peroxidation markers decreased as compared to non-supplemented rats. Status epilepticus induced a lower up-regulation of astrocytic and microglial antigens (GFAP and MHC II, respectively) and production of pro-inflammatory cytokines (IL-1β and TNF-α) in supplemented than in non-supplemented animals. This anti-inflammatory effect was associated with a lower neuronal cell death. In conclusion, α-T dietary supplementation prevents oxidative stress, neuroglial over-activation and cell death occurring after kainate-induced seizures. This evidence paves the way to an anti-inflammatory and neuroprotective role of α-T interventions in epilepsy. 相似文献
998.
999.
Item F Heinzer-Schweizer S Wyss M Fontana P Lehmann R Henning A Weber M Boesiger P Boutellier U Toigo M 《American journal of physiology. Regulatory, integrative and comparative physiology》2011,301(1):R60-R66
In this study, we examined whether glycemic status influences aerobic function in women with type 1 diabetes and whether aerobic function is reduced relative to healthy women. To this end, we compared several factors determining aerobic function of 29 young sedentary asymptomatic women (CON) with 9 women of similar age and activity level with type 1 diabetes [DIA, HbA1c range = 6.9-8.2%]. Calf muscle mitochondrial capacity was estimated by (31)P-magnetic resonance spectroscopy. Capillarization and muscle fiber oxidative enzyme activity were assessed from vastus lateralis and soleus muscle biopsies. Oxygen uptake and cardiac output were evaluated by ergospirometry and N(2)O/SF(6) rebreathing. Calf muscle mitochondrial capacity was not different between CON and DIA, as indicated by the identical calculated maximal rates of oxidative ATP synthesis [0.0307 (0.0070) vs. 0.0309 (0.0058) s(-1), P = 0.930]. Notably, HbA1c was negatively correlated with mitochondrial capacity in DIA (R(2) = 0.475, P = 0.040). Although HbA1c was negatively correlated with cardiac output (R(2) = 0.742, P = 0.013) in DIA, there was no difference between CON and DIA in maximal oxygen consumption [2.17 (0.34) vs. 2.21 (0.32) l/min, P = 0.764], cardiac output [12.1 (1.9) vs. 12.3 (1.8) l/min, P = 0.783], and endurance capacity [532 (212) vs. 471 (119) s, P = 0.475]. There was also no difference between the two groups either in the oxidative enzyme activity or capillary-to-fiber ratio. We conclude that mitochondrial capacity depends on HbA1c in untrained women with type 1 diabetes but is not reduced relative to untrained healthy women. 相似文献
1000.
Giuseppe Olivieri Maria Elena Russo Alberto Di Donato Antonio Marzocchella Piero Salatino 《Journal of biotechnology》2011,156(4):302
Microorganism kinetic growth characterized by substrate inhibition was investigated by means of a continuous stirred tank reactor equipped with a feedback controller of the medium feeding flow rate. The aerobic growth of Pseudomonas sp. OX1 with phenol as carbon/energy source was adopted as a case study to test a new control strategy using dissolved oxygen concentration as a state variable. The controller was successful in steadily operating bioconversion under intrinsically unstable conditions. A simple model of the controlled system was proposed to set the feedback controller.The specific growth rate of Pseudomonas sp. OX1 was successfully described by means of the Haldane model. The regression of the experimental data yielded μM = 0.26 h−1, KPh = 5 × 10−3 g/L and KI = 0.2 g/L. The biomass-to-substrate fractional yield as a function of the specific growth rate did not change moving from substrate-inhibited to substrate-deficient state. The data was modelled according to the Pirt model: m = 1.7 × 10−2 g/(g h), . The specific growth rates calculated for batch and continuous growth were compared. 相似文献