Plasma biomarker profile and clinical correlations in adult patients with tuberous sclerosis complex

Background and objectives: Different pathophysiological mechanisms, especially involving astrocytes, could contribute to Tuberous Sclerosis Complex (TSC). We assessed neurodegeneration and astrocytopathy plasma biomarkers in TSC adult patients to define TSC biomarker profile and investigate clinical-radiological correlations. Methods: TSC patients≥15 years followed at Policlinico "Umberto I" of Rome were consecutively enrolled (July 2021-June 2022). The plasma levels of the following biomarkers were compared between patients and age/sex-matched healthy controls (HC): tTau, pTau181, Abeta40, Abeta42, Neurofilament Light Chain, Glial Fibrillary Acid Protein (GFAP). Results: Thirty-one patients (20 females/11 males; median age 30 years, IQR 24-47) and 38 HC were enrolled. Only GFAP was significantly higher in the whole TSC population than in HC [132.71 (86.14-231.06) vs 44.80 (32.87-66.76) pg/mL, p<0.001], regardless of genotype. GFAP correlated with the disease clinical (ρ=0.498, p=0.005) and radiological severity (ρ=0.417, p=0.001). It was significantly higher in patients with epileptic spasms [254.50 (137.54-432.96) vs 86.92 (47.09-112.76) pg/mL, p<0.0001], moderate-severe intellectual disability [200.80 (78.40-427.6) vs 105.08 (46.80-152.58) pg/mL, p=0.040] and autism spectrum disorder [306.26 (159.07-584.47) vs 109.34 (72.56-152.08) pg/mL, p=0.021]. Discussion: Our exploratory study documented a significant increase of GFAP plasma concentration in TSC adult patients, correlated with their neurological severity, supporting the central role of astrocytopathy in TSC pathophysiology

Synthesis of a Dibromoperylene Phosphoramidite Building Block and Its Incorporation at the 5' End of a G-Quadruplex Forming Oligonucleotide: Spectroscopic Properties and StructuralStudies of the Resulting Dibromoperylene Conjugate

Previous studies indicate that some perylene bisimide derivatives can drive the assembly of DNA G-quad- ruplexes, thus suggesting the possible advantage in the adoption of perylene-conjugated G-rich oligonucleotides in biological and biotechnological applications. Nevertheless, the typical poor solubility of perylene bisimides strongly limits the number of suitable chemical strategies to prepare perylene-conjugated oligonucleotides. In order to overcome these difficulties, we employed the earlier described core twisted perylene derivatives possessing unique optical and electronic properties, besides good solubility in common solvents. As a first result, the large-scale synthesis of a new dibromoperylene derivative (PEOEBr) phosphoramidite building block is herein reported. Furthermore, the structural behavior of the conjugated PEOEBr-GGGTTAGGG (HTRp2) human telomeric repeat was investigated by using CD, UV, fluorescence, and gel electrophoresis techniques in desalted water and in K+- and Na+-containing buffers. We observed that the peculiar property of PEOEBr moieties to form dimers instead of extended aggregates drives the HTRp2 strands toward dimerization and mainly promotes the formation of quadruplex species having both the 50-ends located at the same side of the structures. However, the counterions present in solutions (K+ or Na+) as well as the strand concentration, also contribute to influence the topology and the stoichiometry of formed structures. Furthermore, unlike the unmodified sequence GGGTTAGGG (HTR2), HTRp2 strands quickly associate into G-quadruplexes even in desalted water, as assessed by CD experiments

A Contribution to the Harmonization of Non-targeted NMR Methods for Data-Driven Food Authenticity Assessment

Spectroscopic non-targeted methods are gaining ever-growing importance in quality control and authenticity assessment of food products because of their strong potential for identification of specific features of the products by data-driven classifiers. One of the factors hampering the diffusion of spectroscopic non-targeted methods and data-driven classifiers is the lack of harmonized guidelines for their development and validation. In particular, to date, neither conditions to directly compare spectra recorded by different spectrometers nor studies demonstrating the statistical equivalence of the spectra are available. Among the spectroscopic analytical techniques suitable for the development of non-targeted methods, nuclear magnetic resonance (NMR) offers the unique opportunity to generate statistically equivalent signals. In this paper, the feasibility of NMR spectroscopy to generate statistically equivalent NMR signals from a number of different spectrometers was demonstrated for complex mixtures (aqueous extracts of wheat and flour) by organizing an inter-laboratory comparison involving 36 NMR spectrometers. Univariate statistics along with multivariate analysis were exploited to establish unbiased criteria for assessing the statistical equivalence of the NMR signals. The aspects affecting the signal equivalence were investigated, and possible solutions to reduce the extent of the human error were proposed and applied with satisfactory results. This study furnishes the scientific community with an appropriate and easy procedure to validate non-targeted NMR methods and provides error values to be used as a reference for future studies

Preliminary six-month outcomes of LIMBSAVE (treatment of critical Limb IscheMia with infragenicular Bypass adopting in situ SAphenous VEin technique) registry

Objectives: Guidelines recommend open bypass surgery for long occlusions of infrainguinal arteries. In situ saphenous vein bypass is a standardized technique. The aim of this study was to report preliminary six-month outcomes of a national, multicenter, observational, prospective registry based on the examination of treatment of critical Limb IscheMia with infragenicular Bypass adopting the in situ SAphenous VEin technique (LIMBSAVE). Methods: From January 2018 until October 2019, 428 patients from 41 centers were enrolled in the LIMBSAVE registry. Data were prospectively collected in a dedicated database, including demographics, preoperative risk factors, clinical and diagnostic preoperative assessments, intraoperative measures (including safety and effectiveness of the valvulotome during the surgical procedures), and 30-day follow-up data. Furthermore, estimated six-month outcomes according to Kaplan\u2013Meier curves in terms of primary patency, primary assisted patency, secondary patency, and limb salvage were evaluated. Results: Patients were predominantly male (n = 332, 77.6%) with a mean age of 73.3 years (range 39\u201395). Technical success, defined as bypass pulse after use of the valvulotome, was obtained in all cases. The proximal anastomosis could be reached by the valvulotome in all cases. The mean number of valvulotome uses was 2.5 (range 1\u20135). No vein perforation was reported. In nine cases (2.1%), a vein lesion with intramural hemorrhage occurred. The mean length of hospital stay was 11.1 days (range 1\u201360). At 30-day follow-up, the overall bypass patency rate was 97.4%, and the rate of open or endo reinterventions for failing bypass was 5.4%. At six-month follow-up, the estimated primary patency, primary assisted patency, secondary patency, and limb salvage were 78.1%, 86.2%, 92.1%, and 94.7%, respectively. Conclusions: Preliminary intraprocedural outcomes of the LIMBSAVE registry show that the in situ technique with the valvulotome is safe and effective in disrupting valves and obtaining pulsatility in the saphenous vein. The complication rate related to the use of the valvulotome is low. The six-month preliminary outcomes in terms of overall patency and limb salvage are promising. Further examinations and continuous follow-up are needed to evaluate long-term outcomes

A community-built calibration system: The case study of quantification of metabolites in grape juice by qNMR spectroscopy

Nuclear Magnetic Resonance (NMR) is an analytical technique extensively used in almost every chemical laboratory for structural identification. This technique provides statistically equivalent signals in spite of using spectrometer with different hardware features and is successfully used for the traceability and quantification of analytes in food samples. Nevertheless, to date only a few internationally agreed guidelines have been reported on the use of NMR for quantitative analysis. The main goal of the present study is to provide a methodological pipeline to assess the reproducibility of NMR data produced for a given matrix by spectrometers from different manufacturers, with different magnetic field strengths, age and hardware configurations. The results have been analyzed through a sequence of chemometric tests to generate a community-built calibration system which was used to verify the performance of the spectrometers and the reproducibility of the predicted sample concentrations