Structure and Binding Properties to Blood Co-Factors of the Least Sulfated Galactan Found in the Cell Wall of the Red Alga Botryocladia occidentalis.

Three different populations of sulfated polysaccharides can be found in the cell wall of the red alga Botryocladia occidentalis. In a previous work, the structures of the two more sulfated polysaccharides were revised. In this work, NMR-based structural analysis was performed on the least sulfated polysaccharide and its chemically modified derivatives. Results have revealed the presence of both 4-linked α- and 3-linked ß-galactose units having the following chemical features: more than half of the total galactose units are not sulfated, the α-units occur primarily as 3,6-anhydrogalactose units either 2-O-methylated or 2-O-sulfated, and the ß-galactose units can be 4-O-sulfated or 2,4-O-disulfated. SPR-based results indicated weaker binding of the least sulfated galactan to thrombin, factor Xa, and antithrombin, but stronger binding to heparin cofactor II than unfractionated heparin. This report together with our previous publication completes the structural characterization of the three polysaccharides found in the cell wall of the red alga B. occidentalis and correlates the impact of their composing chemical groups with the levels of interaction with the blood co-factors.

Dimethylthiourea as a Quencher in Hydroxyl Radical Protein Footprinting Experiments.

Hydroxyl radical protein footprinting (HRPF) is a mass-spectrometry-based method for studying protein structures, interactions, conformations, and folding. This method is based on the irreversible labeling of solvent-exposed amino acid side chains by hydroxyl radicals. While catalase is commonly used as a quencher after the labeling of a protein by the hydroxyl radicals to efficiently remove the remaining hydrogen peroxide, it has some disadvantages. Catalase quenching adds a relatively high amount of protein to the sample, limiting the sensitivity of the method due to dynamic range issues and causing significant issues when dealing with more complex samples. We evaluated dimethylthiourea (DMTU) as a replacement for catalase in the quenching HRPF reactions. We observed that DMTU is highly effective at quenching HRPF oxidation. DMTU does not cause the background protein issues that catalase does, resulting in an increased number of protein identifications from complex mixtures. We recommend the replacement of catalase quenching with DMTU for all HRPF experiments.

The Sea Cucumber Thyonella gemmata Contains a Low Anticoagulant Sulfated Fucan with High Anti-SARS-CoV-2 Actions against Wild-Type and Delta Variants.

In this work, we isolated two new sulfated glycans from the body wall of the sea cucumber Thyonella gemmata: one fucosylated chondroitin sulfate (TgFucCS) (17.5 ± 3.5% kDa) and one sulfated fucan (TgSF) (383.3 ± 2.1% kDa). NMR results showed the TgFucCS backbone composed of [→3)-ß-N-acetylgalactosamine-(1→4)-ß-glucuronic acid-(1→] with 70% 4-sulfated and 30% 4,6-disulfated GalNAc units and one-third of the GlcA units decorated at the C3 position with branching α-fucose (Fuc) units either 4-sulfated (65%) or 2,4-disulfated (35%) and the TgSF structure composed of a tetrasaccharide repeating unit of [→3)-α-Fuc2,4S-(1→2)-α-Fuc4S-(1→3)-α-Fuc2S-(1→3)-α-Fuc2S-(1→]n. Inhibitory properties of TgFucCS and TgSF were investigated using SARS-CoV-2 pseudovirus coated with S-proteins of the wild-type (Wuhan-Hu-1) or the delta (B.1.617.2) strains and in four different anticoagulant assays, comparatively with unfractionated heparin. Molecular binding to coagulation (co)-factors and S-proteins was investigated by competitive surface plasmon resonance spectroscopy. Among the two sulfated glycans tested, TgSF showed significant anti-SARS-CoV-2 activity against both strains together with low anticoagulant properties, indicating a good candidate for future studies in drug development.

Abnormal in-plane epitaxy and formation mechanism of vertically aligned Au nanopillars in self-assembled CeO2-Au metamaterial systems.

Metamaterials present great potential in the applications of solar cells and nanophotonics, such as super lenses and other meta devices, owing to their superior optical properties. In particular, hyperbolic metamaterials (HMMs) with exceptional optical anisotropy offer improved manipulation of light-matter interactions as well as a divergence in the density of states and thus show enhanced performances in related fields. Recently, the emerging field of oxide-metal vertically aligned nanocomposites (VANs) suggests a new approach to realize HMMs with flexible microstructural modulations. In this work, a new oxide-metal metamaterial system, CeO2-Au, has been demonstrated with variable Au phase morphologies from nanoparticle-in-matrix (PIM), nanoantenna-in-matrix, to VAN. The effective morphology tuning through deposition background pressure, and the corresponding highly tunable optical performance of three distinctive morphologies, were systematically explored and analyzed. A hyperbolic dispersion at high wavelength has been confirmed in the nano-antenna CeO2-Au thin film, proving this system as a promising candidate for HMM applications. More interestingly, a new and abnormal in-plane epitaxy of Au nanopillars following the large mismatched CeO2 matrix instead of the well-matched SrTiO3 substrate, was discovered. Additionally, the tilting angle of Au nanopillars, α, has been found to be a quantitative measure of the balance between kinetics and thermodynamics during the depositions of VANs. All these findings provide valuable information in the understanding of the VAN formation mechanisms and related morphology tuning.

Structure, anti-SARS-CoV-2, and anticoagulant effects of two sulfated galactans from the red alga Botryocladia occidentalis.

The structure of the sulfated galactan from the red alga Botryocladia occidentalis (BoSG) was originally proposed as a simple repeating disaccharide of alternating 4-linked α-galactopyranose (Galp) and 3-linked ß-Galp units with variable sulfation pattern. Abundance was estimated only for the α-Galp units: one-third of 2,3-disulfation and one-third of 2-monosulfation. Here, we isolated again the same BoSG fractions from the anion-exchange chromatography, obtaining the same NMR profile of the first report. More careful NMR analysis led us to revise the structure. A more complex sulfation pattern was noted along with the occurrence of 4-linked α-3,6-anhydro-Galp (AnGalp) units. Interestingly, the more sulfated BoSG fraction showed slightly reduced in vitro anti-SARS-CoV-2 activities against both wild-type and delta variants, and significantly reduced anticoagulant activity. The BoSG fractions showed no cytotoxic effects. The reduction in both bioactivities is attributed to the presence of the AnGalp unit. Docking scores from computational simulations using BoSG disaccharide constructs on wild-type and delta S-proteins, and binding analysis through competitive SPR assays using blood (co)-factors (antithrombin, heparin cofactor II and thrombin) and four S-proteins (wild-type, delta, gamma, and omicron) strongly support the conclusion about the deleterious impact of the AnGalp unit.

Structural characterization and biological activity of an α-glucan from the mollusk Marcia hiantina (Lamarck, 1818).

Marcia hiantina (Mollusca, Bivalvia) (Lamarck, 1818), is an edible clam mainly distributed along the tropical coastal regions. Recent researches have demonstrated that clams can possess compounds, including polysaccharides, with a wide range of biological actions including antioxidant, immunomodulatory and antitumor activities. Here an α-glucan was isolated from M. hiantina by hot water, purified by anion exchange chromatography, and its structure was characterized by a combination of multiple nuclear magnetic resonance (NMR) methods (1D 1H, 1H-1H COSY, 1H-1H TOCSY, 1H-1H NOESY, 1H-13C HSQC and 1H-13C HSQC-NOESY spectra), gas chromatography-mass spectrometry, and high performance size exclusion chromatography (HPSEC). The analysis from NMR, monosaccharide composition, methylation analyses and HPSEC combined with multi-angle light scattering (MALS) of M. hiantina-derived α-glycan confirmed a branched polysaccharide exclusively composed of glucose (Glc), mostly 4-linked in its backbone, branched occasionally at 6-positions, and having a molecular weight of ~ 570 kDa. The mollusk α-glucan was subjected to four cell-based assays: (i) viability of three cell lines (RAW264.7, HaCaT, and HT-29), (ii) activity on lipopolysaccharide (LPS)-induced prostaglandin production in RAW264.7 cells, (iii) inhibitory activities of in H2O2- and LPS-induced reactive oxygen species (ROS) production in HMC3 cells, and (iv) HaCaT cell proliferation. Results have indicated no cytotoxicity, potent inhibition of both H2O2- and LPS-induced ROS, and potent cell proliferative activity.

A Comprehensive Workflow for the Analysis of Bio-Macromolecular Supplements: Case Study of 20 Whey Protein Products.

The presence of bio-macromolecules as major ingredients is a primary factor in marketing many biologically derived macromolecular supplements. Workflows for analyzing these supplements for quality assurance, adulteration, and other supply-chain difficulties must include a qualitative assessment of small-molecule and macromolecular components; however, no such integrated protocol has been reported for these bio-macromolecular supplements. Twenty whey protein supplements were analyzed using an integrated workflow to identify protein content, protein adulteration, inorganic elemental content, and macromolecular and small-molecule profiles. Orthogonal analytical methods were employed, including NMR profiling, LC-DAD-QToF analysis of small-molecule components, ICP-MS analysis of inorganic elements, determination of total protein content by a Bradford assay, SDS-PAGE protein profiling, and bottom-up shotgun proteomic analysis using LC-MS-MS. All 20 supplements showed a reduced protein content compared to the claimed content but no evidence of adulteration with protein from an unclaimed source. Many supplements included unlabeled small-molecule additives (but nontoxic) and significant deviations in metal content, highlighting the importance of both macromolecular and small-molecule analysis in the comprehensive profiling of macromolecular supplements. An orthogonal, integrated workflow allowed the detection of crucial product characteristics that would have remained unidentified using traditional workflows involving either analysis of small-molecule nutritional supplements or protein analysis.

Sequential docetaxel as adjuvant chemotherapy for node-positive or/and T3 or T4 breast cancer: clinical outcome (Mansoura University).

This trial compared 6 cycles of fluorouracil, epirubicin, and cyclophosphamide (FEC) with a sequential regimen of 3 cycles of FEC followed by 3 cycles of docetaxel (FEC-D) as adjuvant treatment for women with node-positive or/and T3 or T4 breast cancer. Between January 2006 and January 2010, 657 patients with operable breast cancer were randomly assigned to either FEC every 21 days for 6 cycles, or 3 cycles of FEC followed by 3 cycles of docetaxel, both given every 21 days. Radiotherapy was mandatory for all patients who had undergone breast conserving surgery. Radiation to the chest wall, supraclavicular area, was recommended following mastectomy. Hormone-receptor-positive patients received tamoxifen for 5 years after chemotherapy. The primary end point was 5-year disease-free survival (DFS). Median follow-up was 61 months. Five-year DFS rates were 74 % with FEC and 78 % with FEC-D (P = 0.013). Multivariate analysis adjusted for prognostic factors showed a 17 % reduction in the relative risk of relapse with FEC-D. Five-year overall survival rates were 85 % with FEC and 89.4 % with FEC-D, demonstrating a 27 % reduction in the relative risk of death (P = 0.014). The incidence of grade 3-4 neutropenia, the need for hematopoietic growth factor, and incidence of nausea/vomiting were higher with FEC. Docetaxel was associated with more febrile neutropenia, stomatitis, edema, and nail disorders. Though rare overall, there were fewer cardiac events after FEC-D, attributable mainly to the lower anthracycline cumulative dose. Sequential adjuvant chemotherapy with FEC followed by docetaxel significantly improves disease-free and overall survival in node-positive or/and T3 or T4 breast cancer patients. Although the magnitude of the benefit observed with FEC-D, differences in the toxicity profiles of FEC and FEC-D may influence the choice of treatment for patients.

A randomized trial of brief treatment of early- stage Hodgkin lymphoma: Is it effective?

BACKGROUND AND OBJECTIVES: Whether it is possible to reduce the intensity of treatment in early (stage I or II) Hodgkin lymphoma with a favorable prognosis remains unclear. Therefore, we conducted this randomized trial, comparing two treatment groups consisting of a combination chemotherapy regimen of two different intensities followed by involved-field radiation therapy at two different dose levels. DESIGN AND SETTING: Prospective, randomized, in patients referred to the Department Of Clinical Oncology And Nuclear Medicine. PATIENTS AND METHODS: Ninety-eight patients with histologically proven early-stage Hodgkin lymphoma with a favorable prognosis were enrolled in this study between January 2008 and June 2010. They were randomly assigned in one of two treatment arms: arm I received four cycles of ABVD (adriamycin, belomycin, vinblastine, dacarbazine) followed by 30 Gy of involved-field radiation therapy; arm II received two cycles of ABVD followed by 20 Gy of involved-field radiation therapy. RESULTS: During the follow-up period, the 2-year relapse-free survival rates were 96% and 95% in arm I and arm II, respectively (P=.8), while the 2-year overall survival rates were 98% and 95% in arm I and arm II, respectively (P=.16). acute toxicity affected 54% of patients treated with four cycles of ABVD, who had grade III or IV toxicity, as compared with 30% of those receiving two cycles (P<.02). The rates of acute toxicity (grade III or IV) were also higher among patients treated with 30 Gy of involved-field radiation therapy than among those receiving 20 Gy (16% vs. 2.5%, P<.03) . CONCLUSION: In patients with early-stage Hodgkin lymphoma and a favorable prognosis, treatment with two cycles of aBVD followed by 20 Gy of involved-field radiation therapy was as effective as, and less toxic than, four cycles of ABVD followed by 30 Gy of involved-field radiation therapy.

Peripheral venous pressure is an alternative to central venous pressure in paediatric surgery patients.

BACKGROUND: Peripheral venous pressure (PVP) is easily and safely measured. In adults, PVP correlates closely with central venous pressure (CVP) during major non-cardiac surgery. The objective of this study was to evaluate the agreement between CVP and PVP in children during major surgery and during recovery. METHODS: Fifty patients aged 3-9 years, scheduled for major elective surgery, each underwent simultaneous measurements of CVP and PVP at random points during controlled ventilation intraoperatively (six readings) and during spontaneous ventilation in the post-anaesthesia care unit (three readings). In a subset of four patients, measurements were taken during periods of hypotension and subsequent fluid resuscitation (15 readings from each patient). RESULTS: Peripheral venous pressure was closely correlated to CVP intraoperatively, during controlled ventilation (r=0.93), with a bias of 1.92 (0.47) mmHg (95% confidence interval = 2.16-1.68). In the post-anaesthesia care unit, during spontaneous ventilation, PVP correlated strongly with CVP (r = 0.89), with a bias of 2.45 (0.57) mmHg (95% confidence interval = 2.73-2.17). During periods of intraoperative hypotension and fluid resuscitation, within-patient changes in PVP mirrored changes in CVP (r = 0.92). CONCLUSION: In children undergoing major surgery, PVP showed good agreement with CVP in the perioperative period. As changes in PVP parallel, in direction, changes in CVP, PVP monitoring may offer an alternative to direct CVP measurement for perioperative estimation of volume status and guiding fluid therapy.

Cytotoxic bicyclic diterpene from the brown alga Sargassum crispum.

Study of the brown alga Sargassum crispum collected from Red Sea resulted in the isolation of new diterpene with hydroazulene skeleton, Sargassinone (6), some fatty acids ethyl ester andsome fatty acids. The identification of the isolated metabolites was established mainly by spectral methods and chemical transformation of sargassinone (6) to its acetate (7). The two diterpens (6, 7) exhibited substantial cytotoxic activities, as indicated by their IC50 values at the dose of 10 micrograms/ml or less.