A new class of chiral C2‐symmetrical diamino‐oligothiophenes is described to be effective in catalyzing Pd‐mediated asymmetric allylic alkylations in a highly enantioselective manner. The combination ...of experimental as well as crystallographic evidence revealed the key role played by sulfur‐based heteroaromatic rings in the stereodiscriminating step of the procedure. In particular, unprecedented non‐covalent secondary interactions between the inner thiophene and the metal center proved to be essential to create the stereochemical environment necessary in order to guarantee excellent levels of chemical and optical yields.
The synthesis, characterization, and structure‐guided application of a new class of highly versatile chiral C2‐symmetric diamine‐oligothiophene ligands in Pd‐catalyzed asymmetric transformations are ...presented. Experimental investigations of the intimate role of pendant π‐conjugate oligothiophenes in determining the catalytic activity of the corresponding chiral Pd complexes are described. Their unusual behavior opens up new routes toward the logical design of finely tuned organometallic catalysts by remote structural functionalizations.
Molecular remote control has great potential for the design of fine‐tuned organometallic catalysts for stereoselective transformations when the title ligands are incorporated in chiral palladium catalysts as illustrated.
Gene expression profiling (GEP) studies recognized a prognostic role for tumor microenvironment (TME) in diffuse large B-cell lymphoma (DLBCL), but the routinely adoption of prognostic stromal ...signatures remains limited.
Here, we applied the computational method CIBERSORT to generate a 1028-gene matrix incorporating signatures of 17 immune and stromal cytotypes. Then, we carried out a deconvolution on publicly available GEP data of 482 untreated DLBCLs to reveal associations between clinical outcomes and proportions of putative tumor-infiltrating cell types. Forty-five genes related to peculiar prognostic cytotypes were selected and their expression digitally quantified by NanoString technology on a validation set of 175 formalin-fixed, paraffin-embedded DLBCLs from two randomized trials. Data from an unsupervised clustering analysis were used to build a model of clustering assignment, whose prognostic value was also assessed on an independent cohort of 40 cases. All tissue samples consisted of pretreatment biopsies of advanced-stage DLBCLs treated by comparable R-CHOP/R-CHOP-like regimens.
In silico analysis demonstrated that higher proportion of myofibroblasts (MFs), dendritic cells, and CD4+ T cells correlated with better outcomes and the expression of genes in our panel is associated with a risk of overall and progression-free survival. In a multivariate Cox model, the microenvironment genes retained high prognostic performance independently of the cell-of-origin (COO), and integration of the two prognosticators (COO + TME) improved survival prediction in both validation set and independent cohort. Moreover, the major contribution of MF-related genes to the panel and Gene Set Enrichment Analysis suggested a strong influence of extracellular matrix determinants in DLBCL biology.
Our study identified new prognostic categories of DLBCL, providing an easy-to-apply gene panel that powerfully predicts patients’ survival. Moreover, owing to its relationship with specific stromal and immune components, the panel may acquire a predictive relevance in clinical trials exploring new drugs with known impact on TME.
To study the pyramidal tract side effects (PTSEs) induced by the spread of current from the subthalamic nucleus (STN) to the pyramidal tract (PT), in patients with parkinsonism undergoing STN ...stimulation.
14 patients bilaterally implanted with tetrapolar electrodes were assessed. For each side separately, the threshold of adverse effects induced by monopolar stimulation delivered by the chronically used contact was detected. The voltage was progressively increased until the patient experienced discomfort. All the PTSEs induced at 130 Hz (high-frequency stimulation (HFS)) and 2 or 3 Hz (low-frequency stimulation (LFS)) were videotaped. By superimposing the preoperative and postoperative MR images, the minimum distance (R) from the centre of the used contact to the medial border of the PT were measured.
The progressive increase in voltage at HFS induced tonic motor contractions, mainly located in the face, in 27/28 electrodes. LFS induced synchronous rhythmic myoclonus in the same territory. PTSEs induced at threshold voltage by HFS were observed in the upper face at 13/28 electrodes (bilaterally in six cases) and in the contralateral lower face at five electrodes. A positive correlation was found between the stimulus intensity capable of eliciting motor contractions at HFS and R.
HFS of the STN preferentially activates the corticobulbar tract over the corticospinal tract. Therefore, cranial motor contractions need to be looked for during electrical parameter setting. The positive correlation between the electrical intensity threshold for PTSEs and R reflects the need for millimetre accuracy in electrode positioning.
The methanolic extracts (MeOH) obtained from de-stemmed grape pomace samples of five Sicilian red grape cultivars (Nero d′Avola-NA, Nerello Mascalese-NM, Nerello Cappuccio-NC, Frappato-FR and ...Cabernet Sauvignon-CS) were evaluated for their DPPH
and ABTS
− radical scavenging capacity, and submitted to HPLC–UV–DAD and HPLC–MS–ESI analysis to determine the main polyphenolic constituents, namely anthocyanins and flavonols. All the MeOH extracts showed significant antioxidant activity, with some differences between the two methods employed. The NM sample was the most active in both tests. A large variability in the total anthocyanin (TA) and flavonol (TF) contents of the MeOH extracts, as well as in the quantitative distribution of the single anthocyanins and flavonols was observed. Statistically insignificant correlations between the TA
+
TF content and antioxidant activity, as measured by DPPH
and ABTS
− model systems (
r
2
=
0.0607,
P
>
0.05;
r
2
=
0.3471,
P
>
0.05), were established, but the most active sample, NM, showed the highest content of anthocyanins including a free catechol moiety in their structure.
► We measured NH3 fluxes by eddy covariance method using a QC-TILDAS fast analyser. ► High frequency losses were corrected by different spectral methodologies. ► We use theoretical transfer ...functions, ogive and inductance methods. ► We measured NH3 fluxes on irrigated crop fertilized by urea in semi-arid climate. ► The corrections range between −23% and −43% of the measured fluxes.
Several methods are available for evaluating and correcting the underestimation of trace gas fluxes measured by eddy covariance (EC) method and due to the design and the setup of the employed equipment. Different frequency correction factors (CF) to apply to the measured EC ammonia (NH3) fluxes have been applied using the following approaches: (i) the spectral theoretical transfer function (CFTheor) with and without phase shift; (ii) the in situ ogive method (CFO); and (iii) the inductance correction method (CFL). The NH3 fluxes were measured in an experimental field located in south Italy, above a sorghum crop submitted to Mediterranean semi-arid climate and fertilized with urea. A fast analyser based on Tunable Infrared Laser Differential Absorption Spectroscopy (TILDAS) coupled with a quantum cascade (QC) laser was used to measure NH3 concentration at high frequency. The results showed that correction of the values of NH3 EC fluxes over natural surfaces are necessary for taking into account the dumping of high frequency contribution due to the coupling of ammonia fast analyser by QC-TILDAS and sonic anemometer. In particular, the calculated flux losses ranged between −23% (inductance method, with the CF threshold selected to 2.5) and −43% (experimental-ogive method); while the two theoretical transfer function approaches gave comparable loss estimates, i.e. −30 and −31% for the methods with time lag and phase shift, respectively.
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