Characterization of styrene/methyl methacrylate/n-butyl acrylate terpolymer with Kendrick mass defect analysis in electrospray ionization-ion mobility spectrometry-mass spectrometry.

RATIONALE: Synthesis of copolymer is one of the major approaches to establish sophisticated polymers. In copolymer analysis in mass spectrometry (MS), an increase in the number of monomer unit species and/or the polymer molecular weight results in complex mass spectra, and a method is required to solve this problem. METHODS: In this study, electrospray ionization-ion mobility spectrometry-mass spectrometry was employed to analyze styrene/methyl methacrylate/n-butyl acrylate (St/MMA/nBA) terpolymers via Kendrick mass defect (KMD) analysis. An expanded Fourier transform-based noise reduction method for the copolymer was developed to improve the decrease in the signal/noise ratio observed in the higher m/z region. RESULTS: Low-mass terpolymers (0.7 kDa) were identified by comparing the observed and theoretical results using a two-dimensional KMD plot. For the 1.5 kDa terpolymer, the signal overlap, of which KMD value was not matched with the theoretical one, was interpreted by the shift from the theoretical value in the KMD plot. For the 3.0 kDa terpolymers, the compositional candidates were determined by the prediction based on the compositional information of low-mass terpolymers previously analyzed. The 4.5 kDa terpolymer was interpreted after the expanded noise filtering. CONCLUSIONS: The terpolymers, whose molecular weight was up to 4.5 kDa, were successfully characterized at a molecular level. The dependency of the St/MMA/nBA composition on molecular weight was observed; that is, the nBA content decreased with an increase in the molecular weight.

A case of successful treatment with antiretroviral therapy for HIV in a patient with marked liver dysfunction.

Background: Human immunodeficiency virus (HIV) infection is often complicated with hepatitis virus infection. Antiretroviral therapy (ART) should be initiated with caution for patients with severe virus- or drug-induced acute hepatitis while considering factors that might interfere with the initiation of therapy. Case report: Herein, we present a case of a 67-year-old woman who presented with symptoms of severe liver injury of unknown cause. Laboratory examinations revealed HIV infection. The HIV viral load was high, and treatment with ART was considered. However, a liver biopsy could not be performed because of hyperbilirubinemia and the risk of severe hepatic damage. After assessing the risk of further liver damage, ART was safely administered despite hyperbilirubinemia. Treatment with ART could successfully reduce the viral load and bilirubin levels. Conclusion: ART treatment could be safely used for patients with HIV to reduce the viral load and bilirubin levels while avoiding the risk of liver failure.

Does castration status affect docetaxel-related adverse events? :Identification of risk factors for docetaxel-related adverse events in metastatic prostate cancer.

BACKGROUND: Docetaxel-related adverse events (AEs) such as neutropenia and febrile neutropenia (FN) can be life-threatening. A previous in vivo study raised the hypothesis that the castration status affects the rate of hematologic AEs. We aimed to investigate the impact of castration status on the incidence of docetaxel-related AE in metastatic prostate cancer (mPCa) patients. METHODS: We retrospectively analyzed the records of 265 mPCa patients treated with docetaxel, comprising 92 patients with metastatic hormone-sensitive prostate cancer (mHSPC) and 173 patients with metastatic castration-resistant prostate cancer (mCRPC) between January 2015 and December 2021. Common terminology Criteria for Adverse Events (CTCAE) was applied to evaluate AEs. We analyzed the differential incidences between mHSPC and mCRPC, and risk factors of hematologic and nonhematologic AEs using a logistic regression model. RESULTS: The rate of patients who received primary prophylaxis against neutropenia was higher in those with the mHSPC compared with those with the mCRPC (7.5% vs. 33%, p < 0.001). Among the patients without primary prophylaxis, incidence rates of severe neutropenia (CTCAE ≥ Grade3) and FN were 89% and 16% in patients with mCRPC compared to 81% and 18% in those with mHSPC. Logistic regression analysis revealed that age ≥ 75 years and failure to provide primary prophylaxis were independent risk factors of severe neutropenia (odds ratio [OR]: 2.39, 95% confidential interval [CI]: 1.10-5.18 and OR: 15.8, 95% CI: 7.23-34.6, respectively). Eastern Cooperative Oncology Group Performance Status (ECOG-PS) ≧ 1 was an independent risk factor of FN (OR: 2.26, 95% CI: 1.13-4.54). Castration status (mHSPC vs. mCRPC) was not associated with the risks of severe neutropenia and FN. CONCLUSIONS: Castration status did not affect the risk of severe neutropenia or FN in mPCa patients treated with docetaxel regardless of the disease state. Failure to provide primary prophylaxis and advanced patient age are independent risk factors of severe neutropenia; while patients with poor PS are more likely to develop FN. These findings may help guide the clinical decision-making for proper candidate selection of docetaxel treatment.

The function of SARS-CoV-2 spike protein is impaired by disulfide-bond disruption with mutation at cysteine-488 and by thiol-reactive N-acetyl-cysteine and glutathione.

Viral spike proteins play important roles in the viral entry process, facilitating attachment to cellular receptors and fusion of the viral envelope with the cell membrane. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein binds to the cellular receptor angiotensin converting enzyme-2 (ACE2) via its receptor-binding domain (RBD). The cysteine residue at position 488, consisting of a disulfide bridge with cysteine 480 is located in an important structural loop at ACE2-binding surface of RBD, and is highly conserved among SARS-related coronaviruses. We showed that the substitution of Cys-488 with alanine impaired pseudotyped SARS-CoV-2 infection, syncytium formation, and cell-cell fusion triggered by SARS-CoV-2 spike expression. Consistently, in vitro binding of RBD and ACE2, spike-mediated cell-cell fusion, and pseudotyped viral infection of VeroE6/TMPRSS2 cells were inhibited by the thiol-reactive compounds N-acetylcysteine (NAC) and a reduced form of glutathione (GSH). Furthermore, we demonstrated that the activity of variant spikes from the SARS-CoV-2 alpha and delta strains were also suppressed by NAC and GSH. Taken together, these data indicate that Cys-488 in spike RBD is required for SARS-CoV-2 spike functions and infectivity, and could be a target of anti-SARS-CoV-2 therapeutics.

Exposure of the cryptic de-adhesive site FNIII14 in fibronectin molecule and its binding to membrane-type eEF1A induce migration and invasion of cancer cells via ß1-integrin inactivation.

Cell migration is a highly coordinated process that involves not only integrin-mediated adhesion but also de-adhesion. We previously found that a cryptic de-adhesive site within fibronectin molecule, termed FNIII14, weakens cell adhesion to the extracellular matrix by inactivating ß1-integrins. Surprisingly, eukaryotic translation elongation factor-1A (eEF1A), an essential factor during protein biosynthesis, was identified as a membrane receptor that mediates the de-adhesive effect of FNIII14. Here, we demonstrate that FNIII14-mediated de-adhesion causes enhanced migration and invasion in two types of highly invasive/metastatic cancer cells, resulting in the initiation of metastasis. Both in vitro migration and invasion of highly invasive human melanoma cell line, Mum2B, were inhibited by a matrix metalloproteinase (MMP)-2/9 inhibitor or a function-blocking antibody against FNIII14 (anti-FNIII14 Ab), suggesting that MMP-mediated exposure of the cryptic de-adhesive site FNIII14 was responsible for Mum2B cell migration and invasion. The MMP-induced FNIII14 exposure was also shown to be functional in the migration and invasion of highly metastatic mouse breast cancer cell line 4T1. Overexpression and knockdown experiments of eEF1A in Mum2B cells revealed that the migration and invasion were dependent on the membrane levels of eEF1A. In vivo experiments using tumor xenograft mouse models derived from Mum2B and 4T1 cell lines showed that the anti-FNIII14 Ab has a significant anti-metastatic effect. Thus, these results provide novel insights into the regulation of cancer cell migration and invasion and suggest promising targets for anti-metastasis strategies.

New scale-down methodology from commercial to lab scale to optimize plant-derived soft gel capsule formulations on a commercial scale.

A new scale-down methodology from commercial rotary die scale to laboratory scale was developed to optimize a plant-derived soft gel capsule formulation and eventually manufacture superior soft gel capsules on a commercial scale, in order to reduce the time and cost for formulation development. Animal-derived and plant-derived soft gel film sheets were prepared using an applicator on a laboratory scale and their physicochemical properties, such as tensile strength, Young's modulus, and adhesive strength, were evaluated. The tensile strength of the animal-derived and plant-derived soft gel film sheets was 11.7 MPa and 4.41 MPa, respectively. The Young's modulus of the animal-derived and plant-derived soft gel film sheets was 169 MPa and 17.8 MPa, respectively, and both sheets showed a similar adhesion strength of approximately 4.5-10 MPa. Using a D-optimal mixture design, plant-derived soft gel film sheets were prepared and optimized by varying their composition, including variations in the mass of κ-carrageenan, ι-carrageenan, oxidized starch and heat-treated starch. The physicochemical properties of the sheets were evaluated to determine the optimal formulation. Finally, plant-derived soft gel capsules were manufactured using the rotary die method and the prepared soft gel capsules showed equivalent or superior physical properties compared with pre-existing soft gel capsules. Therefore, we successfully developed a new scale-down methodology to optimize the formulation of plant-derived soft gel capsules on a commercial scale.

Identification of the interaction region between hemagglutinin components of the botulinum toxin complex.

The large toxin complex (L-TC) produced by Clostridium botulinum is formed from the M-TC (BoNT/NTNHA complex) by conjugation of M-TC with HA-33/HA-17 trimer consists of two HA-33 proteins and a single HA-17 protein. This association is mediated by HA-70, which interacts with HA-17. The current study aims to identify the regions of the HA-70 molecule that adhere to the HA-33/HA-17 complex. Products from limited proteolysis of HA-70 were resolved by SDS-PAGE and transferred onto PVDF membranes, where they were probed with HA-33/HA-17 in a far-western blot. Among the HA-70 fragments, HA-33/HA-17 bound to those containing at least the C-terminal half of the HA-70 molecule, but not those carrying the N-terminal half. Additional docking simulation analysis indicated that the HA-70 region Gln420-Tyr575 is responsible for binding to HA-17, which is consistent with the far-western blot data. The findings here reveal additional details concerning the three-dimensional structure of the functional HA sub-complex in the botulinum toxin complex.

Size-controlled synthesis of anisotropic TiO2 single nanocrystals using microwave irradiation and their application for dye-sensitized solar cells.

A microwave hydrothermal reaction of colloidal titanates is presented as a cost-effective synthesis to produce TiO(2) single nanocrystals. The photoelectrode consisting of anisotropic nanorods and V-shaped twins has a significant advantage for achieving an appreciable incident photon-to-current conversion efficiency of 85.6% for the dye-sensitized solar cell.

Characterization of cross-linking structures in UV-cured acrylic ester resin by MALDI-MS combined with supercritical methanolysis.

The cross-linking structure of the ultra violet (UV)-cured resin prepared from dipentaerithritol hexacrylate (DPHA) was characterized by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) combined with supercritical methanolysis. The MALDI-mass spectrum of the decomposition products obtained by supercritical methanolysis contained a series of peaks of sodium-cationized methyl acrylate (MA) oligomers up to around m/z = 4000 formed through selective cleavage and methylation occurred at ester linkages in UV-cured DPHA. Furthermore, in order to observe widely distributed sequence lengths in the cross-linking junctions, the decomposed products of the cured resin were then fractionated using size exclusion chromatography followed by the MALDI-MS measurements of the individual fractions. The MALDI-mass spectra of the lower molar mass fractions mainly consisted of a series of peaks of MA oligomers around m/z values of several thousands, whereas those of higher molecular weight showed a broad peak up to m/z ca. 180000. The observed distributions of the supercritical methanolysis products suggested that the network junctions in the given UV-cured resin were composed of up to around 2000 acrylate units.