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1.
World J Clin Oncol ; 15(9): 1117-1121, 2024 Sep 24.
Article de Anglais | MEDLINE | ID: mdl-39351465

RÉSUMÉ

In this editorial, we delve into the article and offer valuable insights into a crucial aspect of gastric cancer aetiology. Gastric cancer is a malignancy emanating from the epithelial lining of the gastric mucosa and one of the most prevalent forms of cancer worldwide. The development of gastric cancer is associated with multiple risk factors, including Helicobacter pylori infection, advanced age, a diet rich in salt, and suboptimal eating patterns. Despite notable reductions in morbidity and mortality rates, gastric cancer remains a formidable public health concern, impacting patients' lives. Advanced glycation end products (AGEs) are complex compounds arising from nonenzymatic reactions within living organisms, the accumulation of which is implicated in cellular and tissue damage; thus, the levels are AGEs are correlated with the risk of diverse diseases. The investigation of AGEs is of paramount importance for the treatment of gastric cancer and can provide pivotal insights into disease pathogenesis and preventive and therapeutic strategies. The reduction of AGEs levels and suppression of their accumulation are promising avenues for mitigating the risk of gastric cancer. This approach underscores the need for further research aimed at identifying innovative interventions that can effectively lower the incidence and mortality rates of this malignancy.

2.
Nano Lett ; 24(38): 11831-11838, 2024 Sep 25.
Article de Anglais | MEDLINE | ID: mdl-39283029

RÉSUMÉ

Topological superconductors (TSCs) offer a promising avenue for delving into exotic states of matter and fundamental physics. We propose a strategy for realizing high transition temperatures (high-Tc) in TSCs by leveraging nontrivial topology alongside a high carrier density near the Fermi level in metal-doped borophenes. We identified 39 candidates with exceptional thermodynamic stability from thousands of Be-intercalated borophenes (Be1-xBx) via extensive structural searches. Seven candidates exhibit high carrier densities, with B7Be2B7 emerging as a particularly promising candidate. This nanosheet displays both type-I and type-II Dirac fermions, indicative of Z2 topological metals, thereby positioning it as an ideal platform for high-Tc TSCs. The high-density π electrons of B7Be2B7 originating from type-II Dirac fermions, coupled with the out-of-plane vibrations of B and Be atoms, significantly enhance the electron-phonon coupling (λ = 1.42), resulting in a substantially high-Tc of 31.5 K. These findings underscore the potential of metal-doped borophenes as a cutting-edge material platform for achieving high-Tc TSCs.

3.
Chemistry ; 30(34): e202400714, 2024 Jun 17.
Article de Anglais | MEDLINE | ID: mdl-38622057

RÉSUMÉ

Quantum chemical calculations using ab initio methods at the MRCI+Q(8,9)/def2-QZVPPD and CCSD(T)/def2-QZVPPD levels as well as using density functional theory are reported for the diatomic molecules AeN- (Ae=Ca, Sr, Ba). The anions CaN- and SrN- have electronic triplet (3Π) ground states with nearly identical bond dissociation energies De ~57 kcal/mol calculated at the MRCI+Q(8,9)/def2-QZVPPD level. In contrast, the heavier homologue BaN- has a singlet (1Σ+) ground state, which is only 1.1 kcal/mol below the triplet (3Σ-) state. The computed bond dissociation energy of (1Σ+) BaN- is 68.4 kcal/mol. The calculations at the CCSD(T)-full/def2-QZVPPD and BP86-D3(BJ)/def2-QZVPPD levels are in reasonable agreement with the MRCI+Q(8,9)/def2-QZVPPD data, except for the singlet (1Σ+) state, which has a large multireference character. The calculated atomic partial charges given by the CM5, Voronoi and Hirshfeld methods suggest small to medium-sized Ae←N- charge donation for most electronic states. In contrast, the NBO method predicts for all species medium to large Ae→N- electronic charge donation, which is due to the neglect of the (n)p AOs of Ae atoms as genuine valence orbitals. Neither the bond orders nor the bond lengths correlate with the bond dissociation energies. The EDA-NOCV calculations show that the heavier alkaline earth atoms Ca, Sr, Ba use their (n)s and (n-1)d orbitals for covalent bonding.

4.
Nano Lett ; 24(11): 3448-3455, 2024 Mar 20.
Article de Anglais | MEDLINE | ID: mdl-38452056

RÉSUMÉ

Unlike graphene derived from graphite, borophenes represent a distinct class of synthetic two-dimensional materials devoid of analogous bulk-layered allotropes, leading to covalent bonding within borophenes instead of van der Waals (vdW) stacking. Our investigation focuses on 665 vdW-stacking boron bilayers to uncover potential bulk-layered boron allotropes through vdW stacking. Systematic high-throughput screening and stability analysis reveal a prevailing inclination toward covalently bonded layers in the majority of boron bilayers. However, an intriguing outlier emerges in δ5 borophene, demonstrating potential as a vdW-stacking candidate. We delve into electronic and topological structural similarities between δ5 borophene and graphene, shedding light on the structural integrity and stability of vdW-stacked boron structures across bilayers, multilayers, and bulk-layered allotropes. The δ5 borophene analogues exhibit metallic properties and characteristics of phonon-mediated superconductors, boasting a critical temperature near 22 K. This study paves the way for the concept of "borophite", a long-awaited boron analogue of graphite.

5.
Chem Sci ; 14(33): 8785-8791, 2023 Aug 23.
Article de Anglais | MEDLINE | ID: mdl-37621437

RÉSUMÉ

The presence of a delocalized π-bond is often considered an essential criterion for achieving planar hypercoordination. Herein, we show that σ-delocalization could be sufficient to make the planar configuration the most stable isomer in a series of planar pentacoordinate s-block metals. High-level ab initio computations reveal that the global minimum of a series of interalkali and interalkali-alkaline earth clusters (LiNa5, Li5Mg+, Na5Mg+, K5Ca+, CaRb5+, Rb5Sr+, and SrCs5+) adopts a singlet D5h structure with a planar pentacoordinate lithium or alkaline earth metal (AE = Mg, Ca, Sr). These clusters are unusual combinations to stabilize a planar pentacoordinate atom, as all their constituents are electropositive. Despite the absence of π-electrons, Hückel's rule is fulfilled by the six σ-electrons. Furthermore, the systems exhibit a diatropic ring current in response to an external magnetic field and a strong magnetic shielding, so they might be classified as σ-aromatic. Therefore, multicenter σ-bonds and the resulting σ-delocalization stabilize these clusters, even though they lack π-aromaticity.

6.
J Chem Phys ; 159(5)2023 Aug 07.
Article de Anglais | MEDLINE | ID: mdl-37526162

RÉSUMÉ

Planar hexacoordination (ph) is only rarely reported in the literature. So far, only a few neutral and cationic molecules possessing phE (E = C, Si, B, Al, Ga) in the most stable isomer are predicted theoretically. Present electronic structure calculations report hitherto unknown anionic planar hexcoordinate beryllium and magnesium, phBe/Mg, as the most stable isomer. Global minimum searches show that the lowest energy structure of BeC6M3- (M = Al, Ga) and MgC6M3- (M = Ga, In, Tl) is the D3h symmetric phBe/Mg clusters, where beryllium/magnesium is covalently bonded with six carbon centers and M is located in a bridging position between two carbon centers. These global minimum phBe/Mg clusters are highly kinetically stable against isomerization, facilitating the experimental confirmation by photoelectron spectroscopy. Noteworthy is the fact that the phBe/Mg center is linked with carbon centers through three 7c-2e delocalized σ bonds and three 7c-2e π bonds, making the cluster double aromatic (σ + π) in nature. The bonding between the Be/Mg and outer ring moiety can be best expressed as an electron-sharing σ-bond between the s orbital of Be+/Mg+ and C6M32- followed by three dative interactions involving empty pπ and two in-plane p orbitals of Be/Mg. Furthermore, Lewis basic M centers of the title clusters can be passivated through the complexation with bulky Lewis acid, 9-boratriptycene, lowering the overall reactivity of the cluster, which can eventually open up the possibility of their large-scale syntheses.

7.
Phys Chem Chem Phys ; 25(30): 20759, 2023 Aug 02.
Article de Anglais | MEDLINE | ID: mdl-37489011

RÉSUMÉ

Correction for 'Structure and bonding of molecular stirrers with formula B7M2- and B8M2 (M = Zn, Cd, Hg)' by Rui Yu et al., Phys. Chem. Chem. Phys., 2020, 22, 12312-12320, https://doi.org/10.1039/D0CP01603A.

8.
Helicobacter ; 28(5): e13007, 2023 Oct.
Article de Anglais | MEDLINE | ID: mdl-37452727

RÉSUMÉ

BACKGROUND: Helicobacter pylori (H. pylori) is closely associated with gastric diseases and has a high prevalence in China. Public platforms are considered common and important tools to publicize H. pylori-related information. This study aimed to assess and compare the content and quality of H. pylori-related videos on TikTok and Bilibili. MATERIALS AND METHODS: A search was performed on the TikTok and Bilibili platforms using the keyword "H. pylori". The source of upload was categorized as for-profit organizations, general users, health professionals, news agencies, nonprofit organizations, and science communicators. The Journal of American Medical Association (JAMA), Global Quality Scale (GQS), and modified DISCERN scores were used to evaluate the quality of the included videos. RESULTS: A total of 93 TikTok videos and 79 Bilibili videos were included and analyzed. TikTok videos had a significantly shorter duration than Bilibili videos (64 vs. 149 s, respectively; p < 0.001). The duration of the video showed a positive correlation with the modified DISCERN and GQS scores (p < 0.001, r = 0.388 and r = 0.437, respectively). The JAMA and modified DISCERN scores of the TikTok video were significantly higher in health professionals and nonprofit organizations than in other sources (p < 0.05). For Bilibili, science communicators had a significantly higher JAMA score than the other video sources (p < 0.001). The videos uploaded by news agencies received more views, comments, shares, and favorites than any other organization or individual (p < 0.001). CONCLUSIONS: In China, H. pylori-related videos from TikTok and Bilibili tended to provide the information regarding the transmission and eradication of H. pylori. However, many videos scored an average rating in content and quality and need to be improved. We recommend that the public obtain H. pylori-related information through videos uploaded by health professionals, nonprofit organizations, and science communicators.


Sujet(s)
Infections à Helicobacter , Helicobacter pylori , Médias sociaux , Humains , Helicobacter pylori/génétique , Sources d'information , Chine , Reproductibilité des résultats
9.
World J Clin Cases ; 11(18): 4267-4276, 2023 Jun 26.
Article de Anglais | MEDLINE | ID: mdl-37449233

RÉSUMÉ

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) is one of the most common disorders in child and adolescent psychiatry, with a prevalence of more than 5%. Despite extensive research on ADHD in the last 10 to 20 years, effective treat-ments are still lacking. Instead, the concept of ADHD seems to have become broader and more heterogeneous. Therefore, the diagnosis and treatment of ADHD remains challenging for clinicians. AIM: To investigate the effects of a multimodal integrated intervention for children with ADHD. METHODS: Between March 2019 and September 2020, a total of 100 children with ADHD who were diagnosed and treated at our hospital were assessed for eligibility, two of whom revoked their consent. A case-control study was conducted in which the children were equally assigned, using a randomized number table, to either a medication group (methylphenidate hydrochloride extended-release tablets and atomoxetine hydrochloride tablets) or a multimodal integrated intervention group (medication + parent training + behavior modification + sensory integration therapy + sand tray therapy), with 49 patients in each group. The clinical endpoint was the efficacy of the different intervention modalities. RESULTS: The two groups of children with ADHD had comparable patient characteristics (P > 0.05). Multimodal integrated intervention resulted in a significantly higher treatment efficacy (91.84%) than medication alone (75.51%) (P < 0.05). Children who received the multimodal integrated intervention showed lower scores in the Conners Parent Symptom Questionnaire and the Weiss Functional Impairment Rating Scale than those treated with medication alone (P < 0.05). The Sensory Integration Scale scores of children in the multimodal integrated intervention group were higher than those of children in the medication group (P < 0.05). Children who received the multimodal integrated intervention had higher compliance and family satisfaction and a lower incidence of adverse events than those treated with medication alone (P < 0.05). CONCLUSION: Multimodal integrated intervention effectively alleviated symptoms associated with ADHD in children. It enhanced their memory and attention with high safety and parental satisfaction, demonstrating good potential for clinical promotion.

10.
Chemphyschem ; 24(15): e202300257, 2023 Aug 01.
Article de Anglais | MEDLINE | ID: mdl-37309297

RÉSUMÉ

The achievement of the rule-breaking planar hypercoordinate motifs (carbon and other elements) is mainly attributed to a practical electronic stabilization mechanism, where the bonding of the central atom pz π electrons is a crucial issue. We have demonstrated that strong multiple bonds between the central atom and partial ligands can be an effective approach to explore stable planar hypercoordinate species. A set of planar tetra-, penta- and hexa-coordinate silicon clusters were herein found to be the lowest-energy structure, which can be viewed as decorating SiO3 by alkali metals in the MSiO3 - , M2 SiO3 and M3 SiO3 + (M=Li, Na) clusters. The strong charge transfer from M atoms to SiO3 effectively results in [M]+ SiO3 2- , [M2 ]2+ SiO3 2- and [M3 ]3+ SiO3 2- salt complexes, where the Si-O multiple bonding and structural integrity of the Benz-like SiO3 framework is maintained better than the corresponding SiO3 2- motifs. The bonding between M atoms and SiO3 motif is best described as M+ forming a few dative interactions by employing its vacant s, p, and high-lying d orbitals. These considerable M←SiO3 interactions and Si-O multiple bonding give rise to the highly stable planar hypercoordinate silicon clusters.

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