32 research outputs found

    Anisotropic Charge Distribution and Anisotropic van der Waals Radius Leading to Intriguing Anisotropic Noncovalent Interactions

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    Although group (IV-VII) nonmetallic elements do not favor interacting with anionic species, there are counterexamples including the halogen bond. Such binding is known to be related to the charge deficiency because of the adjacent atom's electron withdrawing effect, which creates s/p-holes at the bond-ends. However, a completely opposite behavior is exhibited by N-2 and O-2, which have electrostatically positive/negative character around cylindrical-bond-surface/bond-ends. Inspired by this, here we elucidate the unusual features and origin of the anisotropic noncovalent interactions in the ground and excited states of the 2nd and 3rd row elements belonging to groups IV-VII. The anisotropy in charge distributions and van der Waals radii of atoms in such molecular systems are scrutinized. This provides an understanding of their unusual molecular configuration, binding and recognition modes involved in new types of molecular assembling and engineering. This work would lead to the design of intriguing molecular systems exploiting anisotropic noncovalent interactions.open

    Factors influencing the quality of life among women with cancer in Vietnam

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    BackgroundCancer and its treatments significantly affect the quality of life (QoL) of patients. This remains understudied among Vietnamese women with cancer.ObjectivesThis study explored the QoL of Vietnamese women with cancer and identified key influencing factors.MethodIn 2022, this study analyzed 214 Vietnamese women with cancer from four hospitals, assessing pain levels (Visualized Pain Scale), functional capacity (Karnofsky Performance Status Scale), and QoL (SF12). Analyses used SPSS 26.0, including t-tests, ANOVA, and hierarchical linear regression models.ResultsSF12-PCS and SF12-MCS scores were 46.61 ± 9.70 and 46.96 ± 9.06. Pain score (β = −0.304, p β = −0.311, p β = 0.259, p β = −0.311, p r = −0.165, p = 0.016), number of symptoms (r = −0.220, p = 0.001), and pain (r = −0.444, p r = −0.156, p = 0.036) and the number of symptoms (r = −0.362, p r = 0.222, p = 0.001) and (r = 0.281, p ConclusionCulturally sensitive care, pain management, and tailored support programs addressing physical, psychological, spiritual, and social aspects can enhance QoL for these women.</jats:sec

    15-deoxy-Delta(12,14)-Prostaglandin J(2) inhibits human soluble epoxide hydrolase by a dual orthosteric and allosteric mechanism

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    Human soluble epoxide hydrolase (hsEH) is an enzyme responsible for the inactivation of bioactive epoxy fatty acids, and its inhibition is emerging as a promising therapeutical strategy to target hypertension, cardiovascular disease, pain and insulin sensitivity. Here, we uncover the molecular bases of hsEH inhibition mediated by the endogenous 15-deoxy-Δ 12,14-Prostaglandin J 2 (15d-PGJ 2). Our data reveal a dual inhibitory mechanism, whereby hsEH can be inhibited by reversible docking of 15d-PGJ 2 in the catalytic pocket, as well as by covalent locking of the same compound onto cysteine residues C423 and C522, remote to the active site. Biophysical characterisations allied with in silico investigations indicate that the covalent modification of the reactive cysteines may be part of a hitherto undiscovered allosteric regulatory mechanism of the enzyme. This study provides insights into the molecular modes of inhibition of hsEH epoxy-hydrolytic activity and paves the way for the development of new allosteric inhibitors. </p

    15-deoxy-Δ12,14-Prostaglandin J2 inhibits human soluble epoxide hydrolase by a dual orthosteric and allosteric mechanism

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    Human soluble epoxide hydrolase (hsEH) is an enzyme responsible for the inactivation of bioactive epoxy fatty acids, and its inhibition is emerging as a promising therapeutical strategy to target hypertension, cardiovascular disease, pain and insulin sensitivity. Here, we uncover the molecular bases of hsEH inhibition mediated by the endogenous 15-deoxy-Δ12,14- Prostaglandin J2 (15d-PGJ2). Our data reveal a dual inhibitory mechanism, whereby hsEH can be inhibited by reversible docking of 15d-PGJ2 in the catalytic pocket, as well as by covalent locking of the same compound onto cysteine residues C423 and C522, remote to the active site. Biophysical characterisations allied with in silico investigations indicate that the covalent modification of the reactive cysteines may be part of a hitherto undiscovered allosteric regulatory mechanism of the enzyme. This study provides insights into the molecular modes of inhibition of hsEH epoxy-hydrolytic activity and paves the way for the development of new allosteric inhibitors

    The spin label amino acid TOAC and its uses in studies of peptides: chemical, physicochemical, spectroscopic, and conformational aspects

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    We review work on the paramagnetic amino acid 2,2,6,6-tetramethyl-N-oxyl-4-amino-4-carboxylic acid, TOAC, and its applications in studies of peptides and peptide synthesis. TOAC was the first spin label probe incorporated in peptides by means of a peptide bond. In view of the rigid character of this cyclic molecule and its attachment to the peptide backbone via a peptide bond, TOAC incorporation has been very useful to analyze backbone dynamics and peptide secondary structure. Many of these studies were performed making use of EPR spectroscopy, but other physical techniques, such as X-ray crystallography, CD, fluorescence, NMR, and FT-IR, have been employed. The use of double-labeled synthetic peptides has allowed the investigation of their secondary structure. A large number of studies have focused on the interaction of peptides, both synthetic and biologically active, with membranes. In the latter case, work has been reported on ligands and fragments of GPCR, host defense peptides, phospholamban, and β-amyloid. EPR studies of macroscopically aligned samples have provided information on the orientation of peptides in membranes. More recent studies have focused on peptide–protein and peptide–nucleic acid interactions. Moreover, TOAC has been shown to be a valuable probe for paramagnetic relaxation enhancement NMR studies of the interaction of labeled peptides with proteins. The growth of the number of TOAC-related publications suggests that this unnatural amino acid will find increasing applications in the future

    Genome sequences of a novel Vietnamese bat bunyavirus

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    To document the viral zoonotic risks in Vietnam, fecal samples were systematically collected from a number of mammals in southern Vietnam and subjected to agnostic deep sequencing. We describe here novel Vietnamese bunyavirus sequences detected in bat feces. The complete L and S segments from 14 viruses were determined

    Online learning experiences of secondary school students during COVID-19-Dataset from Vietnam

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    This dataset provides an insight into the reality and experiences of online learning as perceived by secondary school students in Vietnam during COVID-related school closures. The dataset addresses four main aspects of online learning, namely (a) students' access to learning devices, (b) their digital skill readiness, (c) their experience with online learning and assessment activities, and (d) their overall evaluation of the effectiveness of online learning. The survey was administered online via Google Form from September to December 2021 with responses received from 5,327 secondary school students in 5 provinces of Vietnam. The dataset is expected to benefit local educators, administrators, and teachers who are interested in COVID educational practices and pedagogical interventions. The dataset can also benefit international researchers who wish to conduct comparative studies on student online learning or who wish to seek further insight into the responsiveness of an educational system to pandemic situations

    Observation of a Single-Stranded DNA/Pyrrolobenzodiazepine Adduct

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    Pyrrolobenzodiazepine (PBD) antitumor agents have, to date, only been observed to bind to duplex DNA, apparently requiring a minor groove environment for covalent bond formation between their C11-position and the C2-NH2 functionality of a guanine base. Using an HPLC/MS assay we have now observed and isolated for the first time PBD adducts with single-stranded DNA fragments. Surprisingly, these adducts could only be formed through dissociation of duplex DNA adducts and not by direct interaction of PBDs with single-stranded DNA. They were sufficiently stable for characterization by MALDI-TOF-MS and remained intact after storing at −20 °C for at least 20 days, although the PBD became detached from the DNA within 7 days if stored at room temperature. Furthermore, addition of a complementary strand allowed the duplex adduct to reform. The relative stability of single-stranded PBD/DNA adducts despite a complete loss of minor groove structure was further confirmed by CD spectroscopic analysis. The CD signal induced by the presence of a PBD molecule in the single-stranded adducts remained prominent despite heating for 2 h at 50–60 °C, thus indicating their relatively robust nature
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