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941.
Francesco Guerrera Federico Femia Paraskevas Lyberis Pier Luigi Filosso Paolo Olivo Lausi Enrico Ruffini 《Reports of Practical Oncology and Radiotherapy》2022,27(1):176
Precise diagnosis in intrathoracic malignancies is paramount for adequate treatment planning. Standard approach is histologic analysis from targeted biopsy obtained with different invasive procedures. Rarely, in difficult clinical scenarios, even gold standard diagnostic procedures can be ineffective in obtaining a satisfying result. Procedural developments and technological improvements applied to the chosen technique can be helpful to deal with such situation. We present two clinical cases of suspected intrathoracic malignancy in which repeated unsuccessful diagnostic procedures had already been attempted. We adopted a protocol based on intraoperative fluorescence during diagnostic thoracoscopy to increase diagnostic efficacy. In both cases we obtained a precise pathological diagnosis. 相似文献
942.
Petraccone L Duro I Erra E Randazzo A Virno A Giancola C 《Nucleosides, nucleotides & nucleic acids》2007,26(6-7):675-679
Differential scanning calorimetry (DSC) and circular dichroism (CD) techniques were used to investigate the physico-chemical properties of the quadruplexes formed by the two different truncations of human telomeric sequence d(TAGGGT) and d(AGGGT), where the adenines were substituted by 2'-deoxy-8-(hydroxyl)adenosine (A --> A OH). CD spectra show that the modified sequences are able to form parallel-stranded quadruplex structure. Analysis of the thermodynamic parameters reveals that the introduction of the modified adenine affects in different way the thermal stability of the [d(TAGGGT)]4 and [d(AGGGT)]4 quadruplexes. 相似文献
943.
Alessia Ruggiero Flavia Squeglia Maria Romano Luigi Vitagliano Alfonso De Simone 《Journal of biomolecular structure & dynamics》2017,35(6):1322-1330
RpfB is multidomain protein that is crucial for Mycobacterium tuberculosis resuscitation from dormancy. This protein cleaves cell wall peptidoglycan, an essential bacterial cell wall polymer formed by glycan chains of β-(1-4)-linked-N-acetylglucosamine (GlcNAc) and N-acetylmuramic acid (MurNAc) cross-linked by short peptide stems. RpfB is structurally complex being composed of five distinct domains, namely a catalytic, a G5 and three DUF348 domains. Here, we have undertaken a combined experimental and computation structural investigations on the entire protein to gain insights into its structure–function relationships. CD spectroscopy and light scattering experiments have provided insights into the protein fold stability and into its oligomeric state. Using the available structure information, we modeled the entire protein structure, which includes the two DUF348 domains whose structure is experimentally unknown, and we analyzed the dynamic behavior of RpfB using molecular dynamics simulations. Present results highlight an intricate mutual influence of the dynamics of the different protein domains. These data provide interesting clues on the functional role of non-catalytic domains of RpfB and on the mechanism of peptidoglycan degradation necessary to resuscitation of M. tuberculosis. 相似文献
944.
Torta F Dyuysekina AE Cavazzini D Fantuzzi A Bychkova VE Rossi GL 《Biochimica et biophysica acta》2004,1703(1):21-29
Cellular Retinol-Binding Protein type I (CRBP) exhibits very high affinity for its ligand, bound within a buried cavity completely shielded from the outside medium. Three-dimensional structure and backbone dynamics in aqueous solution at neutral pH, either in the absence or in the presence of retinol, fail to represent the protein in a state capable of ligand uptake and release. The question was asked whether changes in the composition of the outside medium might facilitate ligand dissociation. Acidic aqueous solutions and water-alcohol mixtures were selected, among the best described denaturing solvents, to investigate their effects on the stability of the carrier-ligand complex and the conformational state of the protein upon ligand release. Circular dichroism (CD) and fluorescence spectroscopy were used to probe protein secondary and tertiary structure, compactness and retinol dissociation. While in purely aqueous media retinol dissociation parallels the acid-induced denaturation of the carrier, in water-alcohol mixtures it occurs in a range of co-solvent content lower than that required for protein denaturation. In light of these results, it is suggested that local solvent properties in vivo might modulate protein conformation and flexibility and thus play a fundamental role in the control of retinol exchange between carrier and membrane-bound donors and acceptors. 相似文献
945.
946.
F Patti A Nicoletti C Leone S Messina E D'Amico S Lo Fermo V Paradisi E Bruno G Quattrocchi P Veroux L Di Pino L Costanzo M Zappia 《PloS one》2012,7(8):e41227
Background
Chronic cerebrospinal venous insufficiency (CCSVI) has been associated to multiple sclerosis (MS).Objective
To evaluate the possible association between CCSVI and MS, using a population-based control design.Methods
A random cohort of 148 incident MS patients were enrolled in the study. We have also studied 20 patients with clinically isolated syndrome (CIS), 40 patients with other neurological diseases (OND), and 172 healthy controls. Transcranial (TCC) and Echo Color Doppler (ECD) were carried out in 380 subjects. A subject was considered CCSVI positive if ≥2 venous hemodynamic criteria were fulfilled.Results
CCSVI was present in 28 (18.9%) of the MS patients, in 2 (10%) of CIS patients, in 11 (6.4%) of the controls, and in 2 (5%) of the OND patients. A significant association between MS and CCSVI was found with an odds ratio of 3.41 (95% confidence interval 1.63–7.13; p = 0.001). CCSVI was significantly more frequent among MS subjects with a disease duration longer than 144 months (26.1% versus 12.6% of patients with duration shorter than 144 months; p = 0.03) and among patients with secondary progressive (SP) and primary progressive (PP) forms (30.2% and 29.4, respectively) than in patients with relapsing remitting (RR) MS (14.3%). A stronger association was found considering SP and PP forms (age adjusted OR = 4.7; 95% CI 1.83–12.0, p = 0.001); the association was weaker with the RR patients (age adjusted OR = 2.58; 95%CI 1.12–5.92; p = 0.02) or not significant in CIS group (age adjusted OR = 2.04; 95%CI 0.40–10.3; p = 0.4).Conclusions
A higher frequency of CCSVI has been found in MS patients; it was more evident in patients with advanced MS, suggesting that CCSVI could be related to MS disability. 相似文献947.
948.
Gianni Bedini Angelino Carta Giovanni Zecca Fabrizio Grassi Gabriele Casazza Luigi Minuto 《Plant Systematics and Evolution》2011,294(3-4):273-280
Rhamnus glaucophylla Sommier is an endemic small tree or shrub belonging to sect. Eurhamnus. It grows on cliffs of the Apuan Alps and of the Lucca Apennine in Tuscany (Italy). ISSRs were used to detect the genetic diversity within and among five populations representative of the species distribution range. Moderate levels of genetic diversity were revealed as percentage of polymorphic band (PPB) both at the population (PPB?=?22.63%, H S?=?0.0801, Sh?=?0.1193) and species level (PPB?=?48.68%, H T?=?0.1155, Sh?=?0.1837). The correlation between genetic and geographic distances was not significant (Mantel test, r?=?0.17; P?<?0.26). The information on the pattern of genetic variation obtained in this work bears important implications for conservation management, and in particular for ex situ conservation programmes involving long-term seed storage in seed banks. 相似文献
949.
The marking behaviour of the European badger (Meles meles L., 1758) in a low-density population of NW Italy was investigated by examining the distribution and pattern of use of latrines in relation to space-use by a badger social group, as assessed by radiotracking. Latrines were mostly placed close to linear features and marked the core area of the group. The winter-spring peak in latrine use suggested that marking behaviour was correlated to reproductive cycle and involved in sexual advertisement. 相似文献
950.
Ida Autiero Menotti Ruvo Roberto Improta Luigi Vitagliano 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(4):1006-1016