Chemical composition and antioxidant activity of essential oil, various organic extracts of Cistus ladanifer and Cistus libanotis growing in Eastern Morocco

In the present work, we studied the chemical composition of the essential oil of Cistus ladanifer and Cistus libanotis growing in Eastern Morocco. The essential oils were obtained by hydrodistillation and their chemical composition was analysed using gas chromatography- mass spectrometry (GC–MS). Camphene, borneol, cyclohexanol-2, 2, 6 tremethyl, terpineol-4 and α-pinene were the main constituents of the essential oil of C. ladanifer, while in the essential oil of C. libanotis we obtained terpineol-4, γ-terpinene, camphene, sabinene, α-terpinene and α-pinene. The antioxidant potential of various extracts (water, ethanol, ethanol: water (50:50), methanol, methanol: water (50:50), acetonitrile) and essential oils of C. ladanifer and C. libanotis were carried out by the method of 1,1-diphenyl-1-picrylhydrazylhydrate (DPPH) free radical scavenging. Total phenolic and flavonoid contents were determined. The result show that C. ladanifer of the leaves of methanol: water (50:50) extract had the highest value of total phenolic content and the lowest was present in ethanol: water (50:50) extract of the stem and acetonitrile extract of the flowers of C. libanotis. From our experimental results, the extract of flowers, fruit, stem and leaves of those plants showed highest potential as free radical scavengers.Keywords: Antioxidant, phenolics, flavonoids, essential oil, extracts, gas chromatography- mass spectrometry (GC–MS).African Journal of Biotechnology Vol. 12(34), pp. 5314-532

High-throughput sequencing of the T-cell receptor repertoire: pitfalls and opportunities.

T-cell specificity is determined by the T-cell receptor, a heterodimeric protein coded for by an extremely diverse set of genes produced by imprecise somatic gene recombination. Massively parallel high-throughput sequencing allows millions of different T-cell receptor genes to be characterized from a single sample of blood or tissue. However, the extraordinary heterogeneity of the immune repertoire poses significant challenges for subsequent analysis of the data. We outline the major steps in processing of repertoire data, considering low-level processing of raw sequence files and high-level algorithms, which seek to extract biological or pathological information. The latest generation of bioinformatics tools allows millions of DNA sequences to be accurately and rapidly assigned to their respective variable V and J gene segments, and to reconstruct an almost error-free representation of the non-templated additions and deletions that occur. High-level processing can measure the diversity of the repertoire in different samples, quantify V and J usage and identify private and public T-cell receptors. Finally, we discuss the major challenge of linking T-cell receptor sequence to function, and specifically to antigen recognition. Sophisticated machine learning algorithms are being developed that can combine the paradoxical degeneracy and cross-reactivity of individual T-cell receptors with the specificity of the overall T-cell immune response. Computational analysis will provide the key to unlock the potential of the T-cell receptor repertoire to give insight into the fundamental biology of the adaptive immune system and to provide powerful biomarkers of disease

Single-cell sequencing reveals clonal expansions of pro-inflammatory synovial CD8 T cells expressing tissue-homing receptors in psoriatic arthritis.

Psoriatic arthritis (PsA) is a debilitating immune-mediated inflammatory arthritis of unknown pathogenesis commonly affecting patients with skin psoriasis. Here we use complementary single-cell approaches to study leukocytes from PsA joints. Mass cytometry demonstrates a 3-fold expansion of memory CD8 T cells in the joints of PsA patients compared to peripheral blood. Meanwhile, droplet-based and plate-based single-cell RNA sequencing of paired T cell receptor alpha and beta chain sequences show pronounced CD8 T cell clonal expansions within the joints. Transcriptome analyses find these expanded synovial CD8 T cells to express cycling, activation, tissue-homing and tissue residency markers. T cell receptor sequence comparison between patients identifies clonal convergence. Finally, chemokine receptor CXCR3 is upregulated in the expanded synovial CD8 T cells, while two CXCR3 ligands, CXCL9 and CXCL10, are elevated in PsA synovial fluid. Our data thus provide a quantitative molecular insight into the cellular immune landscape of psoriatic arthritis

Characterization of polypropylene surface treated in a CO2 plasma

The polypropylene modification in CO2 plasma mainly contributes to degradation, functionalization, and cross-linking. The degradation, whose rate is depending on CO2 dissociation and oxygen atom formation, is a quite slow reaction and it is associated with surface topography alteration, especially of the amorphous phase of the polypropylene. The surface roughness increases with the treatment duration and the amorphous phase is more degraded than the crystallized part. The functionalization, corresponding to an increase of the surface energy (57.3 mJ.m(-2) in 30 s), and to an oxidation (23 oxygen at.%) with the appearance of alcohol, ketone, and acid functions is a much faster phenomenon. Cross-linking takes also place during this type of treatment and will reinforce the stability of the modified surface

Chemical composition and antioxidant activity of essentiel oil, various organic extracts of Cistus ladanifer and Cistus libanotis growing in Eastern Morocco

peer reviewedIn the present work, we studied the chemical composition of the essential oil of Cistus ladanifer and Cistus libanotis growing in Eastern Morocco. Camphene, borneol, cyclohexanol-2, 2, 6 tremethyl, terpineol-4 and α-pinene were the main constituents of the essential oil of C. ladanifer, while in the essential oil of C. libanotis we obtained terpineol-4, γ-terpinene, camphene, sabinene, α-terpinene and α-pinene. The result show that C. ladanifer of the leaves of methanol: water (50:50) extract had the highest value of total phenolic content and the lowest was present in ethanol: water (50:50) extract of the stem and acetonitrile extract of the flowers of C. libanotis. From our experimental results, the extract of flowers, fruit, stem and leaves of those plants showed highest potential as free radical scavenger

ToF-SIMS ability to quantify surface chemical groups: Correlation with XPS analysis and spectrochemical titration

High-density polyethylene (HDPE) and polypropylene (PP) films were analysed by time-of-flight secondary ion mass spectrometry (ToF-SIMS) in a quantitative way in order to study chemical modifications produced by CO2 plasma surface treatments. Although there are many works devoted to the study of surface modification by plasma treatments, this contribution aims at proving the SIMS ability to quantify superficial functions. For that purpose, results obtained by spectrochemical titration (fluorescence labelling with thionine acetate), XPS measurement and ToF-SIMS analyses were compared. The results obtained with these three different techniques showed the same behaviour, i.e. a fast carboxylic functionalization of the polymer surface with the plasma treatment time. The good correlation between the spectrochemical titration and ToF-SIMS results brings out clearly the capacity of the ToF-SIMS technique to quantify surface chemical species. But this requires that we should be able to identify the secondary ions originating from the studied functions. Copyright (C) 2001 John Wiley & Sons, Ltd

Is gene panel sequencing more efficient than clinical-based gene sequencing to diagnose autoinflammatory diseases? A randomized study

International audienceThe aim of this study was to compare the effectiveness of the gene-panel next-generation sequencing (NGS) strategy versus the clinical-based gene Sanger sequencing for the genetic diagnosis of autoinflammatory diseases (AIDs). Secondary goals were to describe the gene and mutation distribution in AID patients and to evaluate the impact of the genetic report on the patient's medical care and treatment. Patients with AID symptoms were enrolled prospectively and randomized to two arms, NGS (n = 99) (32–55 genes) and Sanger sequencing (n = 197) (one to four genes). Genotypes were classified as ‘consistent/confirmatory’, ‘uncertain significance’ or ‘non-contributory’. The proportion of patients with pathogenic genotypes concordant with the AID phenotype (consistent/confirmatory) was significantly higher with NGS than Sanger sequencing [10 of 99 (10·1%) versus eight of 197 (4·1%)]. MEFV, ADA2 and MVK were the most represented genes with a consistent/confirmed genotype, whereas MEFV, NLRP3, NOD2 and TNFRSF1A were found in the ‘uncertain significance’ genotypes. Six months after the genetic report was sent, 54 of 128 (42·2%) patients had received effective treatment for their symptoms; 13 of 128 (10·2%) had started treatment after the genetic study. For 59 of 128 (46%) patients, the results had an impact on their overall care, independent of sequencing group and diagnostic conclusion. Targeted NGS improved the diagnosis and global care of patients with AIDs