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The COVID-19 pandemic has exerted a global impact on both physical and mental health, and clinical populations have been disproportionally affected. To date, however, the mechanisms underlying the deleterious effects of the pandemic on pre-existing clinical conditions remain unclear. Here we investigated whether the onset of the pandemic was associated with an increase in brain/blood levels of inflammatory markers and MRI-estimated brain age in patients with chronic low back pain (cLBP), irrespective of their infection history. A retrospective cohort study was conducted on 56 adult participants with cLBP (28 'Pre-Pandemic', 28 'Pandemic') using integrated Positron Emission Tomography/ Magnetic Resonance Imaging (PET/MRI) and the radioligand [ 11 C]PBR28, which binds to the neuroinflammatory marker 18 kDa Translocator Protein (TSPO). Image data were collected between November 2017 and January 2020 ('Pre-Pandemic' cLBP) or between August 2020 and May 2022 ('Pandemic' cLBP). Compared to the Pre-Pandemic group, the Pandemic patients demonstrated widespread and statistically significant elevations in brain TSPO levels (P =.05, cluster corrected). PET signal elevations in the Pandemic group were also observed when 1) excluding 3 Pandemic subjects with a known history of COVID infection, or 2) using secondary outcome measures (volume of distribution -V T - and V T ratio - DVR) in a smaller subset of participants. Pandemic subjects also exhibited elevated serum levels of inflammatory markers (IL-16; P <.05) and estimated BA (P <.0001), which were positively correlated with [ 11 C]PBR28 SUVR (r's ≥ 0.35; P's < 0.05). The pain interference scores, which were elevated in the Pandemic group (P <.05), were negatively correlated with [ 11 C]PBR28 SUVR in the amygdala (r = -0.46; P<.05). This work suggests that the pandemic outbreak may have been accompanied by neuroinflammation and increased brain age in cLBP patients, as measured by multimodal imaging and serum testing. This study underscores the broad impact of the pandemic on human health, which extends beyond the morbidity solely mediated by the virus itself., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Detection of microstructural white matter injury in traumatic brain injury (TBI) requires specialised imaging methods, of which diffusion tensor imaging (DTI) has been extensively studied. Newer fibre alignment estimation methods, such as constrained spherical deconvolution (CSD), are better than DTI in resolving crossing fibres that are ubiquitous in the brain and may improve the ability to detect microstructural injuries. Furthermore, automatic tract segmentation has the potential to improve tractography reliability and accelerate workflow compared to the manual segmentation commonly used. In this study, we compared the results of deterministic DTI based tractography and manual tract segmentation with CSD based probabilistic tractography and automatic tract segmentation using TractSeg. 37 participants with a history of TBI (with Glasgow Coma Scale 13-15) and persistent symptoms, and 41 healthy controls underwent deterministic DTI-based tractography with manual tract segmentation and probabilistic CSD-based tractography with TractSeg automatic segmentation.Fractional anisotropy (FA) and mean diffusivity of corpus callosum and three bilateral association tracts were measured. FA and MD values derived from both tractography methods were generally moderately to strongly correlated. CSD with TractSeg differentiated the groups based on FA, while DTI did not. CSD and TractSeg-based tractography may be more sensitive in detecting microstructural changes associated with TBI than deterministic DTI tractography. Additionally, CSD with TractSeg was found to be applicable at lower b-value and number of diffusion-encoding gradients data than previously reported., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Type 1 diabetes (T1D) is an autoimmune disease resulting from the demolition of β-cells that are responsible for producing insulin in the pancreas. Treatment with insulin (lifelong applying) and islet transplantation (in rare cases and severe diseases), are standards of care for T1D. Pancreas or islet transplantation have some limitations, such as lack of sufficient donors and longtime immune suppression for preventing allograft rejection. Recent studies demonstrate that autologous hematopoietic stem cells (HSC) can regenerate immune tolerance against auto-antigens. Taking advantage of this feature, autologous HSC transplantation (auto-HSCT) is likely the only treatment for T1D that is associated with lasting and complete remission. None of the other evaluated immunotherapies worldwide had the clinical efficacy of auto-HSCT. Therapy with auto-HSCT is insulin-independent rather than reducing insulin needs or delaying loss of insulin production. This review provided the latest findings in auto-HSCT for treatment of T1D., Competing Interests: Declaration of Competing Interest The authors declare no conflicts of interest., (Copyright © 2022. Published by Elsevier B.V.)

In the current study, the impact of microbial transglutaminase (MTGase)-mediated crosslinking on the thermally denatured egg white protein (TD-EWP) made in alkaline pH in relation to their gelling properties of in gel and emulsion gel systems was investigated. Unlike native EWP that was not a good substrate for MTGase due to its compact structure, SDS-PAGE and gel solubility data showed the TD-EWP was sufficiently cross-linked by MTGase. The MTGase significantly (p < 0.05) increased the gel strength, fracture stress, fracture strain, and TPA parameters and decreased the frequency dependence of elastic modulus and stress dependence of creep compliance of TD-EWP gel and emulsion gel samples. The enhanced mechanical properties of the TE-EWP gelled samples treated with MTGase may be suitable for delivering sensitive compounds as well as in fabricating tailored scaffolds in tissue engineering and biomedical products., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The kinetics, equilibrium and thermodynamics studies of adsorptive desulfurization and denitrogenation to eliminate the refractory sulfur and nitrogen compounds like BT, DBT, quinoline and carbazole of model fuel by mesoporous material (MSU-S) and cobalt modified mesoporous material (CoO-MSU-S) adsorbents were carried out. The adsorption performance, capacity and selectivity of the adsorbent toward sulfur and nitrogen compounds were examined. Equilibrium and kinetics experiments confirmed that Co +2 impregnation would enhance the adsorption capacity of MSU-S. The results demonstrated that CoO-MSU-S led to a considerable improvement in the adsorption performance. The adsorption amounts reached 18.41, 21.20, 39.65 and 24.60 mg.g -1 for BT, DBT, quinoline and carbazole, respectively. The Langmuir isotherm model showed good fittings with the experimental equilibrium data for benzothiophene, dibenzothiophene and carbazole, and the data for quinoline was expressed well by the Freundlich for CoO-MSU-S adsorbent. Negative Gibbs free energy showed that all sulfur and nitrogen compounds were adsorbed spontaneously. The experimental data revealed that the pseudo-second-order model can describe the kinetics of adsorption of compounds on the adsorbent. The data obtained from the breakthrough curves indicated that DBT < BT < carbazole < quinoline order for the selectivity of modified adsorbent towards the adsorbates., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Gellan gum was employed to modulate the technological functionality and in vitro degradation properties of egg white heat-induced hydrogels at different pH values (4.0 and 7.0). The results showed that the enrichment with gellan gum at pH value of 7.0 did not drastically modify the firmness of egg white gel, but at pH 4.0 the addition of gellan significantly improved the hardness and the compressive stress required for the rupturing of the egg white hydrogels. The enrichment with gellan also modulated the swelling behavior of egg white hydrogels as well as significantly improved their water holding capacity. The scanning electron microscopy (SEM) indicated that the composite gellan/egg white hydrogels formed at pH 4.0 and 7.0 had denser microstructures than the corresponding single-component egg white protein hydrogels. The Fourier transform infra-red (FT-IR) spectroscopy also was used to characterize the interactions between egg white proteins and gellan gum. Furthermore, the results revealed that the enrichment of egg white gels with gellan gum drastically increased their stability against in vitro gastrointestinal degradation which can enhance their applications in the site-specific bioactive delivery., (Copyright © 2019 Elsevier B.V. All rights reserved.)

This work addresses the fabrication and characterization of gels from emulsions stabilized by heat-denatured and nanofibrillated whey protein isolate (WPI) using citric acid and CaCl 2 as cold-gelling agents. Nano-thick fibrils and wormlike aggregates were produced by heating of WPI at pH 2.0 and 8.0, respectively. Fibrillated WPI, heat-denatured WPI, and their mixture at a concentration of 65 mg mL -1 and pH 8.0 were used to stabilize oil-in-water emulsions. Emulsions stabilized by fibrillated WPI showed a higher creaming stability than samples stabilized by heat-denatured and mixed fibrillated/heat-denatured WPI. However, they were more polydisperse and had larger droplets. Gelation of emulsions by citric acid through the generation of covalent bonds was confirmed by OPA colorimetric method and FT-IR spectroscopy. Emulsion gels prepared by citric acid-mediated cross-linking were firmer than those formed by CaCl 2 and also showed a higher ability to hold water and retain oil. Scanning electron microscopy also demonstrated a more open and porous structure for ion-induced emulsion gels compared to citric acid-induced counterparts. Generally, the results indicated that the citric acid as a new gelling agent and different forms of WPI aggregates can be used in the formulation of edible emulsion gels with modifiable functional properties., (Copyright © 2018 Elsevier B.V. All rights reserved.)

We sought to investigate white matter abnormalities in mild traumatic brain injury (mTBI) using diffusion-weighted magnetic resonance imaging (DW-MRI). We applied a global approach based on tract-based spatial statistics skeleton as well as constrained spherical deconvolution tractography. DW-MRI was performed on 102 patients with mTBI within two months post-injury and 30 control subjects. A robust global approach considering only the voxels with a single-fiber configuration was used in addition to global analysis of the tract skeleton and probabilistic whole-brain tractography. In addition, we assessed whether the microstructural parameters correlated with age, time from injury, patient's outcome and white matter MRI hyperintensities. We found that whole-brain global approach restricted to single-fiber voxels showed significantly decreased fractional anisotropy (FA) (p = 0.002) and increased radial diffusivity (p = 0.011) in patients with mTBI compared with controls. The results restricted to single-fiber voxels were more significant and reproducible than those with the complete tract skeleton or the whole-brain tractography. FA correlated with patient outcomes, white matter hyperintensities and age. No correlation was observed between FA and time of scan post-injury. In conclusion, the global approach could be a promising imaging biomarker to detect white matter abnormalities following traumatic brain injury.

Whey protein nanofibrils are gaining interest to fabricate cold-set hydrogels due to their ability to gel at lower concentrations than parent proteins. In the present research, fibrillated protein solution was gelled with three different divalent cation salts including CaCl2, MnCl2 and ZnCl2 and the textural and functional characteristics of the resulting hydrogel samples were studied. Atomic force microscopy indicated that the flexible micron-scaled fibrils with nanometric thickness (up to 8.0nm) that formed at pH 2.0 underwent breaking in length upon post-formation pH rise to 7.5. Whilst heat-denatured protein solution failed to form self-supporting gel at pH 7.5, fibrillated protein solution gelled by all three types of cations. Fibrillation increased the protein solution consistency coefficient (K) much more than heat denaturation. It was suggested based on Fourier-transform infra-red (FT-IR) spectra that some hydrogen bonds were disrupted by fibrillation. Zn(2+)-induced gel was firmer, had a higher water holding capacity and a more compact microstructure, as well, required a higher compressive stress to fracture than its counterparts. Nonetheless, the Mn(2+)- and Ca(2+)-induced gels disintegrated to a much lesser extent in both pepsin-free and pepsin-present simulated gastric juice than Zn(2+)-induced sample. Chitosan coating approximately halved the simulated degradability of all gel samples., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Structure-function relationships underlying laccases properties are very limited that makes these enzymes interesting for protein engineering approaches. Therefore in the current study, a thermostable laccase that was isolated from Bacillus sp. HR03 with the ability of bilirubin oxidation besides its laccase and tyrosinase activity is used. The extensive application of this enzyme is limited by its low expression level in Escherichia coli. Based on sequence alignments and structural studies, three single amino acid substitutions, D500G, D500E, D500S and a glycine insertion, are introduced using site-directed mutagenesis to evaluate the role of Asp(500) located in the C-terminal segment close to the T1 copper center. Substitution of aspartic acid with less sterically hindered, conserved residue such as glycine increase kcat (2.3 fold) and total activity (7.3 fold) which is accompanied by a significant increase in the expression level up to 3 fold. Biochemical characterization and structural studies using far-UV CD and fluorescence spectroscopy reveal the importance of C-terminal copper-binding loop in the laccase functional expression and catalytic efficiency. Kinetic characterization of the purified mutants toward 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), syringaldazine (SGZ) and bilirubin, shows that substrate specificity is left unchanged., (Copyright © 2013 Elsevier B.V. All rights reserved.)