[en] Lyoluminescence is the light emitted when irradiated solid substances are dissolved. A large range of organic materials exhibit lyoluminescence, among the more sensitive of which are monosaccharides and amino acids. A dose response curve for mannose (C₆H₁₂O₆) and an example of lyoluminescence apparatus are illustrated. The principle advantage of lyoluminescence dosimetry is that lyoluminescent phosphors may be used which closely approximate the chemical composition of tissue. Therefore all radiation fields KERMA in the phosphor approximates KERMA in tissue, and by design of dosimeter there will be a similar correspondence for absorbed dose. There are indications that the light conversion efficiency of lyoluminescent phosphors is not as dependent on LET as observed for thermoluminescent phosphors, and the possibility exists therefore, of an approximate tissue equivalent response in neutron and mixed radiation fields

[en] Highlights: • M6P glycosylation is a key factor for lysosomal enzyme targeting and efficacy of ERT. • M6P glycosylation on rhGAA, the only ERT for Pompe disease, was not fully reported. • This study investigated M6P glycosylation on rhGAA using LC-ESI-HCD-MS/MS. • All M6P glycans constitute 1.0% of the 78 glycans of rhGAA. • Four types of ten M6P glycans and their three attachment sites are newly identified. Myozyme is a recombinant human acid alpha-glucosidase (rhGAA) that is currently the only drug approved for treating Pompe disease, and its low efficacy means that a high dose is required. Mannose-6-phosphate (M6P) glycosylation on rhGAA is a key factor influencing lysosomal enzyme targeting and the efficacy of enzyme replacement therapy (ERT); however, its complex structure and relatively small quantity still remain to be characterized. This study investigated M6P glycosylation on rhGAA using liquid chromatography (LC)–electrospray ionization (ESI)–high-energy collisional dissociation (HCD) tandem mass spectrometry (MS/MS). The glycans released from rhGAA were labeled with procainamide to improve mass ionization efficiency and the sensitivity of MS/MS. The relative quantities (%) of 78 glycans were obtained, and 1.0% of them were glycans containing M6P (M6P glycans). These were categorized according to their structure into 4 types: 3 newly found ones, comprising high-mannose-type M6P glycans capped with N-acetylglucosamine (GlcNAc) (2 variants, 17.5%), hybrid-type M6P glycans (2 variants, 11.2%), and hybrid-type M6P glycans capped with GlcNAc (3 variants, 6.9%), as well as high-mannose-type M6P glycans (3 variants, 64.4%). HCD-MS/MS spectra identified six distinctive M6P-derived oxonium ions. The glycopeptides obtained from protease-digested rhGAA were analyzed using nano-LC-ESI-HCD-MS/MS, and the extracted-ion chromatograms of M6P-derived oxonium ions confirmed three M6P glycosylation sites comprising Asn 140, Asn 233 (newly found), and Asn 470 attached heterogeneously to nine M6P glycans (two types), eight M6P glycans (four types), and seven M6P glycans (two types), respectively. This is the first study of rhGAA to differentiate M6P glycans and identify their attachment sites, despite rhGAA already being an approved drug for Pompe disease.

[en] Full text: Lymphoscintigraphy using ^99mTc labeled nanocolloids has been effectively used for determining the status of the sentinel lymph node (SLN) which helps in the further management of primary cancers such as melanoma and breast. The uptake of such nanocolloids at the SLN is entirely due to their particle size and is associated with a number of limitations. Hence, efforts are on for development of radiolabeled receptor-specific agents for SLN detection. Since mannose based macromolecules have been shown to have receptor-mediated uptake in the sentinel node, the aim of the present work is to radiolabel dextran-cysteine-mannose derivative (DCM20) and carry out its biological evaluation for its suitability for use in SLN detection. Materials and Methods: DCM20 conjugate was radiolabeled with ^99mTc using ^99mTc carbonyl precursor. The radiolabeled complex was characterized by HPLC using a gradient system with acetonitrile/water as solvents as well as by TLC (Methanol: Conc. HCl 95:5). In vivo biological evaluation was carried out in Wistar rat model by injecting ∼ 50-100 μL (∼ 200-1000kBq) of the preparation in the footpad. Scintigraphic imaging and biodistribution experiments were performed. Results: The product could be obtained in ∼ 85-90% yield with good in vitro stability. The radiolabeled DCM20 conjugate showed specific and high retention in the SLN (7.56 ± 0.68% Injected dose at 1 h p.i.). The washout from the site of injection was also very high thereby reducing the background and improving the sensitivity of SLN detection. Conclusion: ^99mTc labeling and biological evaluation of a mannose based ligand was performed in animal model, which showed very high retention in the SLN with good sensitivity

[en] A continuous flow procedure for the synthesis of methyl glycosides (Fischer glycosylation) of various monosaccharides using a heterogenous catalyst has been developed. In-depth analysis of the isomeric composition was undertaken and high consistency with corresponding results observed under microwave heating was obtained. Even in cases where addition of water was needed to achieve homogeneity—a prerequisite for the flow experiments—no detrimental effect on the conversion was found. The scalability was demonstrated on a model case (mannose) and as part of the target-oriented synthesis of D-glycero-D-manno heptose, both performed on multigram scale. Graphical abstract:

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[en] The lyoluminescence (LL) spectra emitted when irradiated carbohydrates were dissolved in pure water can be interpreted as the superposition of emission from singlet oxygen 'collisional pairs'. The amino acid spectra in pure water are consistent with excited carbonyl emissions. The results therefore provide further evidence that the self-reaction of peroxy radicals is the underlying mechanism of organic LL in pure water. In the presence of sensitisers, the spectra became characteristic of the sensitiser. The factors affecting the accuracy and precision of glutamine lyoluminescence dosimetry (LLD) were investigated. The dependence of the LL yield on the mass of glutamine dissolved, dosemeter irradiation temperature, solvent temperature, and on the storage time both before and after heat treatment (HT) was investigated. The participation of glutamine LLD in two IAEA intercomparisons of various high-dose measuring techniques is described and its performance assessed. The application of mannose LLD to clinical dosimetry and glutamine LLD to industrial radiation processing is discussed. Finally, a preliminary investigation was performed into the LL properties of halogenated nucleosides. (author)

[en] Highlights: • Expression of MCFD2 was up-regulated in human oral squamous cell carcinoma (OSCC). • MCFD2 expression is associated with regional lymph node metastasis. • MCFD2 induced cellular invasion and migration and decreased cellular adhesion. • MCFD2 regulated secretion of galectin 3 binding protein via MCFD2-LMAN1 interaction. • MCFD2 might be a novel therapeutic target for patients with metastatic OSCCs. Multiple coagulation factor deficiency protein 2 (MCFD2), a binding partner of lectin mannose binding 1 (LMAN1), causes combined deficiencies of coagulation factors V and VIII. MCFD2 function in inherited hematologic disorders is well elucidated; however, little is known about its role in human tumorigenesis. The aim of the current study was to investigate the states of MCFD2 in oral squamous cell carcinoma (OSCC). The expression of MCFD2 was up-regulated significantly in all cell lines examined. Evaluation of the cellular functions associated with tumoral metastasis showed that MCFD2 knockdown (shMCFD2) cells exhibited significantly lower cellular invasiveness and migration and higher cellular adhesion compared with shControl cells. Of note, shMCFD2 cells also showed weak immunoreactivity of LMAN1 and a lower secretion level of galactoside-binding soluble 3 binding protein (LGALS3BP). In addition to in vitro validation, clinical data on 70 patients with OSCC indicated that state of MCFD2 expression level is associated with regional lymph node metastasis. Altogether, we have demonstrated that MCFD2 promotes cancer metastasis by regulating LMAN1 and LGALS3BP expression levels. Hence, MCFD2 may represent a promising candidate for a novel therapeutic target for patients with metastatic OSCCs.

[en] Quality control of proteins is an essential process for maintaining normal cell activity. It ensures that only correctly folded proteins are produced and terminally misfolded proteins are eliminated by degradation. ER-associated degradation (ERAD) of misfolded proteins is an important aspect of protein quality control system. Recent studies have revealed that glycoprotein glycans play significant roles in this process. It includes polyubiquitination, deglycosylation, and proteasomal degradation. In the present study, a systematic analysis of these steps was carried out using chemically synthesized glycopeptides. We revealed that N-linked glycopeptides are degraded by 20S proteasome, but with drastically reduced rate compared to non-glycosylated peptide. This result strongly suggests that deglycosylating activity of peptide:N-glycanase (PNGase) is important for the facile degradation of glycoproteins. Our study showed, for the first time, that PNGase cleaves truncated glycans as short as chitobiose from peptide. However, this cleavage required the presence of hydrophobic region nearby N-glycosylation site. Furthermore, analysis of interactions with F-box protein Fbs1 was conducted with fluorescent correlation spectroscopy (FCS). It was shown that the presence of Fbs1 perturb the activity of PNGase toward high-mannose-type glycopeptides

[en] In mannose, grain-size and grain-size band width have been shown to have considerable effect on lyoluminescence (LL) yield and fading characteristics. The effects of these on sensitivity and reproducibility of dose interpretation are reported in this work. Dose reproducibility of better than 0.3% is recorded among narrow grain-size band samples while dose coefficient of 5.31 change in LL yield per Gy is obtained for the more uniform grain-sized samples. ((orig.))

[en] Highlights: • S-layer protein of L. kefiri CIDCA 8348 (SLP8348) is recognized by ConA. • Uptake of SLP8348 by murine macrophages is inhibited by glucose, mannose and EGTA. • SLP8348 significantly increased LPS-induced response of macrophages. • SLP8348-LPS synergism is abrogated by EGTA, indicating a role of Ca⁺² in the effect. • Results suggest the potentiality of SLP8348 for development of new adjuvants. The S-layer is a (glyco)-proteinaceous envelope constituted by self-assembled subunits that form a two-dimensional lattice covering the surface of different species of Bacteria and Archaea. It could be considered as one of the most abundant biopolymers in our planet. Because of their unique self-assembly features, exhibiting repetitive identical physicochemical properties down to the subnanometer scale, as well as their involvement in specific interactions with host cells, the S-layer proteins (SLPs) show a high potential application in different areas of biotechnology, including the development of antigen carriers or new adjuvants. The presence of a glycosylated SLP on potentially probiotic Lactobacillus kefiri strains was previously described by our research group. In this study, we aim to investigate the role of carbohydrates present in the SLP from L. kefiri CIDCA 8348 (SLP-8348) in their internalization by murine macrophages, as well as to analyze their immunomodulatory capacity and their effect on LPS-stimulated macrophages. RAW 264.7 cells internalized the SLP-8348 in a process that was mediated by carbohydrate-receptor interactions since it was inhibited by glucose, mannose or EGTA, a Ca⁺² chelating agent. These results correlated with the recognition of SLP-8348 by ConA lectin. We further show that while SLP-8348 was not able to induce the activation of macrophages by itself, it favored the LPS-induced response, since there was a significant increase in the expression of surface cell markers MHC-II, CD86 and CD40, as well as in IL-6 and IL-10 expression at both transcript and protein levels, in comparison with LPS-stimulated cells. The presence of EGTA completely abrogated this synergistic effect. Taken together, these results strongly suggest the involvement of both glycosidic residues and Ca⁺² ions in the recognition of SLP-8348 by cellular receptors on murine macrophages. Moreover, these results suggest the potentiality of the SLP-8348 for the development of new adjuvants capable of stimulating antigen presenting cells by interaction with glycan receptors.

No abstract available