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71.
Ilaria Ferrarotti Beata Poplawska-Wisniewska Maria Teresa Trevisan Janine Koepke Marc Dresel Rembert Koczulla Stefania Ottaviani Raffaele Baldo Marina Gorrini Giorgia Sala Luana Cavallon Tobias Welte Joanna Chorostowska-Wynimko Maurizio Luisetti Sabina Janciauskiene 《PloS one》2015,10(8)
The Z deficiency in α1-antitrypsin (A1ATD) is an under-recognized condition. Alpha1-antitrypsin (A1AT) is the main protein in the α1-globulin fraction of serum protein electrophoresis (SPE); however, evaluation of the α1-globulin protein fraction has received very little attention. Serum Z-type A1AT manifests in polymeric forms, but their interference with quantitative immunoassays has not been reported. Here, 214 894 samples were evaluated by SPE at the G. Fracastoro Hospital of Verona, Italy. Patients with an A1AT level ≤ 0.92 g/L were recalled to complete A1ATD diagnosis. In parallel, to qualitatively and quantitatively characterize A1AT, sera samples from 10 PiZZ and 10 PiMM subjects obtained at the National Institute of Tuberculosis and Lung Diseases in Warsaw, Poland, were subjected to non-denaturing 7.5% PAGE and 7.5% SDS-PAGE followed by Western blot. Moreover, purified A1AT was heated at 60°C and analyzed by a non-denaturing PAGE and 4–15% gradient SDS-PAGE followed by Western blot as well as by isolelectrofocusing and nephelometry. A total of 966 samples manifested percentages ≤ 2.8 or a double band in the alpha1-zone. According to the nephelometry data, 23 samples were classified as severe (A1AT ≤ 0.49 g/L) and 462 as intermediate (A1AT >0.49≤ 1.0 g/L) A1ATD. Twenty subjects agreed to complete the diagnosis and an additional 21 subjects agreed to family screening. We detected 9 cases with severe and 26 with intermediate A1ATD. Parallel experiments revealed that polymerization of M-type A1AT, when measured by nephelometry or isolelectrofocusing, yields inaccurate results, leading to the erroneous impression that it was Z type and not M-type A1AT. We illustrate the need for confirmation of Z A1AT values by “state of the art” method. Clinicians should consider a more in-depth investigation of A1ATD in patients when they exhibit serum polymers and low α1-globulin protein levels by SPE. 相似文献
72.
Raffaele Antonelli Incalzi Filippo Aucella Dario Leosco Giuliano Brunori Michela Dalmartello Giuseppe Paolisso 《PloS one》2015,10(11)
Chronic kidney disease (CKD) is highly prevalent in the elderly and negatively impacts survival and health status. Thus, nephrological competence is mandatory for a skilled geriatrician. The present study aimed to assess nephrological competence in a sample of geriatricians recruited through a web survey. To this aim, a 12-items questionnaire was produced by an expert panel of nephrologists and geriatricians and was available online for members of the Italian Society of Gerontology and Geriatrics (SIGG). Two-hundred-eighty-seven geriatricians volunteered to fill in the questionnaire. The majority of them indirectly estimated the glomerular filtration rate (GFR) using mainly the Cockroft-Gault (C-G) formula. Selected nephrological exams, such as urinary Na and serum D-vitamin measurements, did not qualify as routine exams although the majority of geriatricians supplemented their patients with fat-soluble secosteroids. Ten percent of geriatricians asked for nephrological consultation only for stage 5 CKD patients and 30,9% only for stage 4 or 5. Erythropoietin supplementation was common practice for the majority of geriatricians, while only one third of them systematically used a procedure intended to prevent the contrast induced nephropathy (CIN). Finally, an alleged 50% adherence to the international guidelines for the management of CKD patients emerged from the questionnaire. Overall, results from this survey strongly recommend promoting nephrological education among geriatricians. Didactic standards for in training geriatricians need to be updated and the cooperation between geriatrics and nephrological societies promoted. 相似文献
73.
Emanuela Zannin Riccardo Pellegrino Alessandro Di Toro Andrea Antonelli Raffaele L. Dellacà Luciano Bernardi 《PloS one》2015,10(6)
Background
It is not known whether parasympathetic outflow simultaneously acts on bronchial tone and cardiovascular system waxing and waning both systems in parallel, or, alternatively, whether the regulation is more dependent on local factors and therefore independent on each system. The aim of this study was to evaluate the simultaneous effect of different kinds of stimulations, all associated with parasympathetic activation, on bronchomotor tone and cardiovascular autonomic regulation.Methods
Respiratory system resistance (Rrs, forced oscillation technique) and cardio-vascular activity (heart rate, oxygen saturation, tissue oxygenation index, blood pressure) were assessed in 13 volunteers at baseline and during a series of parasympathetic stimuli: O2 inhalation, stimulation of the carotid sinus baroreceptors by neck suction, slow breathing, and inhalation of methacholine.Results
Pure cholinergic stimuli, like O2 inhalation and baroreceptors stimulation, caused an increase in Rrs and a reduction in heart rate and blood pressure. Slow breathing led to bradycardia and hypotension, without significant changes in Rrs. However slow breathing was associated with deep inhalations, and Rrs evaluated at the baseline lung volumes was significantly increased, suggesting that the large tidal volumes reversed the airways narrowing effect of parasympathetic activation. Finally inhaled methacholine caused marked airway narrowing, while the cardiovascular variables were unaffected, presumably because of the sympathetic activity triggered in response to hypoxemia.Conclusions
All parasympathetic stimuli affected bronchial tone and moderately affected also the cardiovascular system. However the response differed depending on the nature of the stimulus. Slow breathing was associated with large tidal volumes that reversed the airways narrowing effect of parasympathetic activation. 相似文献74.
Raffaele Liuzzi Federica Savino Vittoria D’Avino Mariagabriella Pugliese Laura Cella 《PloS one》2015,10(10)
Background
Purpose of the present work was to investigate thermoluminescent dosimeters (TLDs) response to intraoperative electron radiation therapy (IOERT) beams. In an IOERT treatment, a large single radiation dose is delivered with a high dose-per-pulse electron beam (2–12 cGy/pulse) during surgery. To verify and to record the delivered dose, in vivo dosimetry is a mandatory procedure for quality assurance. The TLDs feature many advantages such as a small detector size and close tissue equivalence that make them attractive for IOERT as in vivo dosimeters.Methods
LiF:Mg,Ti dosimeters (TLD-100) were irradiated with different IOERT electron beam energies (5, 7 and 9 MeV) and with a 6 MV conventional photon beam. For each energy, the TLDs were irradiated in the dose range of 0–10 Gy in step of 2Gy. Regression analysis was performed to establish the response variation of thermoluminescent signals with dose and energy.Results
The TLD-100 dose-response curves were obtained. In the dose range of 0–10 Gy, the calibration curve was confirmed to be linear for the conventional photon beam. In the same dose region, the quadratic model performs better than the linear model when high dose-per-pulse electron beams were used (F test; p<0.05).Conclusions
This study demonstrates that the TLD dose response, for doses ≤10Gy, has a parabolic behavior in high dose-per-pulse electron beams. TLD-100 can be useful detectors for IOERT patient dosimetry if a proper calibration is provided. 相似文献75.
Many analyses published in the last decade suggest that enzymes isolated from cold-adapted organisms are characterized by a higher flexibility of their molecular structure. Recently, it has been argued that all cold-adapted enzymes with catalytic efficiency greater than that of their mesophilic counterparts display local flexibility or rigidity that are likely to cooperate, each acting on specific areas of the enzyme structure. Here we report an analysis of the normalized thermal B-factor distributions in psychrophilic proteins compared with those of their mesophilic and thermophilic counterparts with the aim to detect statistically significant local variations of relative backbone flexibility possibly linked to cold adaptation. We utilized a strategy based mainly on intra-family comparison of local distribution of normalized B-factors. After careful statistical treatment of data, the picture emerging from our results suggests that the distribution of the flexibility in psychrophilic enzymes is locally more heterogeneous than in their respective mesophilic homologues. 相似文献
76.
Antonio Placido Fran?ois Sieber Anthony Gobert Raffaele Gallerani Philippe Giegé Laurence Maréchal-Drouard 《Nucleic acids research》2010,38(21):7711-7717
All tRNAHis possess an essential extra G–1 guanosine residue at their 5′ end. In eukaryotes after standard processing by RNase P, G–1 is added by a tRNAHis guanylyl transferase. In prokaryotes, G–1 is genome-encoded and retained during maturation. In plant mitochondria, although trnH genes possess a G–1 we find here that both maturation pathways can be used. Indeed, tRNAHis with or without a G–1 are found in a plant mitochondrial tRNA fraction. Furthermore, a recombinant Arabidopsis mitochondrial RNase P can cleave tRNAHis precursors at both positions G+1 and G–1. The G–1 is essential for recognition by plant mitochondrial histidyl-tRNA synthetase. Whether, as shown in prokaryotes and eukaryotes, the presence of uncharged tRNAHis without G–1 has a function or not in plant mitochondrial gene regulation is an open question. We find that when a mutated version of a plant mitochondrial trnH gene containing no encoded extra G is introduced and expressed into isolated potato mitochondria, mature tRNAHis with a G–1 are recovered. This shows that a previously unreported tRNAHis guanylyltransferase activity is present in plant mitochondria. 相似文献
77.
Maria Luisa Balestrieri Alfonso Giovane Lara Milone Francesca Felice Carmela Fiorito Valeria Crudele Annaclaudia Esposito Raffaele Rossiello Pellegrino Biagio Minucci Bartolomeo Farzati Luigi Servillo Claudio Napoli 《Journal of biochemical and molecular toxicology》2010,24(6):351-360
Exposure of human endothelial progenitor cells (EPCs) to tumor necrosis factor‐α (TNF‐α) reduced their number and biological activity. Yet, signal transduction events linked to TNF‐α action are still poorly understood. To address this issue, we examined the possible effect of fasudil and Y27632, two inhibitors of Rho kinase pathway, which is involved in endothelial dysfunction, atherosclerosis, and in‐ flammation. Results demonstrated that incubation with fasudil starting from 50 μM but not Y27632 determined a dose‐dependent improvement of EPC number during exposure to TNF‐α (P < 0.05 vs. TNF‐α alone). Analysis of the signal transduction pathway activated by TNF‐α revealed that the increased expression of p‐p38 was not significantly altered by fasudil. Instead, fasudil blocked the TNF‐α induced phosphorylation of Erk1/2 (P < 0.05 vs. TNF‐α) as well as the inhibitor of Erk1/2‐specific phosphorylated form, i.e., PD98059 (P < 0.05 vs. TNF‐α). These results were confirmed by analysis of these kinases by confocal microscopy. Finally, 2D‐DIGE and MALDI‐TOF/TOF analysis of EPCs treated with fasudil revealed increased expression levels of an actin‐related protein and an adenylyl cyclase associated protein and decreased expression levels of proteins related to radical scavenger and nucleotide metabolism. These findings suggest that fasudil positively affects EPC number and that other major signals might take part to this complex pathway. © 2010 Wiley Periodicals, Inc. J Biochem Mol Toxicol 24:351–360, 2010; View this article online at wileyonlinelibrary.com . DOI 10.1002/jbt.20345 相似文献
78.
Prospero Di Pierro Loredana Mariniello Angela Sorrentino Reynaldo Villalonga Belkis Chico Raffaele Porta 《Amino acids》2010,38(2):669-675
Putrescine (1,4-diaminobutane) was covalently linked to alginate and low-methoxyl pectin to synthesize new aminated polysaccharides.
Both putrescine–pectin and –alginate conjugates, although the latter at higher concentrations, were found to be able to act
as effective acyl acceptor transglutaminase substrates in vitro using both dimethylated casein and soy flour proteins as acyl
donors. Monodansylcadaverine, a well known acyl acceptor transglutaminase substrate, dose-dependently counteracted the covalent
binding of the aminated polysaccharides to the proteins. Putrescine–pectin conjugate was also tested to prepare, in combination
with soy flour proteins, edible films in the presence of purified microbial transglutaminase. Characterization of the enzymatically
crosslinked films showed a significant decreased water vapor permeability, with respect to the ones obtained with non-aminated
pectin in the presence of transglutaminase, as well as improved mechanical properties, such as high extensibility. Possible
biotechnological applications of hydrocolloid films containing putrescine–polysaccharide derivatives enzymatically crosslinked
to proteins were suggested. 相似文献
79.
Raffaele Ingenito Charlotte Burton Annunziata Langella Xun Chen Karolina Zytko Antonello Pessi Jun Wang Elisabetta Bianchi 《Bioorganic & medicinal chemistry letters》2010,20(1):236-239
Reverse cholesterol transport (RCT) is believed to be the primary mechanism by which HDL and its major protein apoA-I protect against atherosclerosis. Starting from the inactive 22-amino acid peptide representing the consensus sequence of the class A amphipathic helical repeats of apoA-I, we designed novel peptides able to mobilize cholesterol from macrophages in vitro, and to stimulate the formation of ‘nascent HDL’ particles, with potency comparable to the entire apoA-I protein. 相似文献
80.
Nina Desai Anastasia Alex Faten AbdelHafez Anthony Calabro James Goldfarb Aaron Fleischman Tommaso Falcone 《Reproductive biology and endocrinology : RB&E》2010,8(1):119
In vitro ovarian follicle culture is a new frontier in assisted reproductive technology with tremendous potential, especially
for fertility preservation. Folliculogenesis within the ovary is a complex process requiring interaction between somatic cell
components and the oocyte. Conventional two-dimensional culture on tissue culture substrata impedes spherical growth and preservation
of the spatial arrangements between oocyte and surrounding granulosa cells. Granulosa cell attachment and migration can leave
the oocyte naked and unable to complete the maturation process. Recognition of the importance of spatial arrangements between
cells has spurred research in to three-dimensional culture system. Such systems may be vital when dealing with human primordial
follicles that may require as long as three months in culture. In the present work we review pertinent aspects of in vitro
follicle maturation, with an emphasis on tissue-engineering solutions for maintaining the follicular unit during the culture
interval. We focus primarily on presenting the various 3-dimensional culture systems that have been applied for in vitro maturation
of follicle:oocyte complexes. We also try to present an overview of outcomes with various biomaterials and animal models and
also the limitations of the existing systems. 相似文献