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1.
Proc Natl Acad Sci U S A ; 119(15): e2117004119, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35394864

RESUMO

GPR126 is a member of the adhesion G protein-coupled receptors (aGPCRs) that is essential for the normal development of diverse tissues, and its mutations are implicated in various pathological processes. Here, through screening 34 steroid hormones and their derivatives for cAMP production, we found that progesterone (P4) and 17-hydroxyprogesterone (17OHP) could specifically activate GPR126 and trigger its downstream Gi signaling by binding to the ligand pocket in the seven-transmembrane domain of the C-terminal fragment of GPR126. A detailed mutagenesis screening according to a computational simulated structure model indicated that K1001ECL2 and F1012ECL2 are key residues that specifically recognize 17OHP but not progesterone. Finally, functional analysis revealed that progesterone-triggered GPR126 activation promoted cell growth in vitro and tumorigenesis in vivo, which involved Gi-SRC pathways in a triple-negative breast cancer model. Collectively, our work identified a membrane receptor for progesterone/17OHP and delineated the mechanisms by which GPR126 participated in potential tumor progression in triple-negative breast cancer, which will enrich our understanding of the functions and working mechanisms of both the aGPCR member GPR126 and the steroid hormone progesterone.


Assuntos
Progesterona , Receptores Acoplados a Proteínas G , Receptores de Progesterona , Neoplasias de Mama Triplo Negativas , 17-alfa-Hidroxiprogesterona/metabolismo , Linhagem Celular Tumoral , Humanos , Progesterona/metabolismo , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Transdução de Sinais , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo
2.
Nano Lett ; 24(11): 3448-3455, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38452056

RESUMO

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.

3.
Gastroenterology ; 164(7): 1165-1179.e13, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36813208

RESUMO

BACKGROUND & AIMS: Aberrant epigenetic events mediated by histone methyltransferases and demethylases contribute to malignant progression of colorectal cancer (CRC). However, the role of the histone demethylase ubiquitously transcribed tetratricopeptide repeat on chromosome X (UTX) in CRC remains poorly understood. METHODS: UTX conditional knockout mice and UTX-silenced MC38 cells were used to investigate UTX function in tumorigenesis and development of CRC. We performed time of flight mass cytometry to clarify the functional role of UTX in remodeling immune microenvironment of CRC. To investigate metabolic interaction between myeloid-derived suppressor cells (MDSCs) and CRC, we analyzed metabolomics data to identify metabolites secreted by UTX-deficient cancer cells and taken up by MDSCs. RESULTS: We unraveled a tyrosine-mediated metabolic symbiosis between MDSC and UTX-deficient CRC. Loss of UTX in CRC resulted in methylation of phenylalanine hydroxylase, preventing its degradation and subsequently increasing tyrosine synthesis and secretion. Tyrosine taken up by MDSCs was metabolized to homogentisic acid by hydroxyphenylpyruvate dioxygenase. Homogentisic acid modified protein inhibitor of activated STAT3 via carbonylation of Cys 176, and relieved the inhibitory effect of protein inhibitor of activated STAT3 on signal transducer and activator of transcription 5 transcriptional activity. This in turn, promoted MDSC survival and accumulation, enabling CRC cells to acquire invasive and metastatic traits. CONCLUSIONS: Collectively, these findings highlight hydroxyphenylpyruvate dioxygenase as a metabolic checkpoint to restrict immunosuppressive MDSCs and to counteract malignant progression of UTX-deficient CRC.


Assuntos
Neoplasias Colorretais , Dioxigenases , Animais , Camundongos , Dioxigenases/metabolismo , Ácido Homogentísico , Histona Desmetilases/genética , Histona Desmetilases/metabolismo , Metilação , Microambiente Tumoral
4.
Chemistry ; 30(34): e202400714, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38622057

RESUMO

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.

5.
BMC Public Health ; 24(1): 57, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166928

RESUMO

BACKGROUND: Gastric cancer has attracted widespread attention on social media due to its high incidence and severity. The Bilibili, TikTok, and YouTube video-sharing platforms have received considerable interest among general health consumers. Nevertheless, it remains unclear whether the information in videos on these platforms is of satisfactory content and quality. METHODS: A total of 300 eligible videos related to gastric cancer were screened from three video-sharing platforms, Bilibili, TikTok, and YouTube, for assessment and analysis. First, the basic information presented in the videos was recorded. Next, we identified the source and content type of each video. Then, the Global Quality Scale (GQS), Journal of the American Medical Association (JAMA), and Modified DISCERN were used to assess the educational content and quality of each video. A comparative analysis was undertaken of the videos procured from these three sources. RESULTS: We identified six categories of uploaders of the 300 videos: 159 videos (53%) were uploaded by health professionals, 21 videos (7%) by users in science communications, 29 videos (9.67%) by general users, 27 videos (9%) from news agencies, 63 videos (12%) by nonprofit organizations, and one video (0.33%) by a for-profit organization. In terms of the content types of the 300 videos, we identified five distinct categories. There were 48 videos (16%) on early signals, 12 videos (4%) on late symptoms, 40 videos (13.33%) on etiologies and causations, 160 videos (53.33%) on scientific introductions, and 40 videos (13.33%) on treatment methods. The overall quality of the videos was evaluated by the GQS, JAMA, and Modified DISCERN and was found to be medium, with scores of 2.6/5, 2.41/4, and 2.71/5 points, respectively. CONCLUSIONS: This innovative study demonstrates that videos on social media platforms can help the public learn about early signals, late symptoms, treatment methods, etiologies and causations, and scientific introductions of gastric cancer. However, both the content and quality of uploaded recordings are inadequate currently. More efforts should be made to enhance the content and quality of videos on gastric cancer and to increase public awareness.


Assuntos
Mídias Sociais , Neoplasias Gástricas , Estados Unidos , Humanos , Neoplasias Gástricas/diagnóstico , Comunicação , Escolaridade , Pessoal de Saúde , Reprodutibilidade dos Testes , Gravação em Vídeo , Disseminação de Informação
6.
Arch Gynecol Obstet ; 309(5): 1815-1823, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38421424

RESUMO

PURPOSE: Preeclampsia is a major cause of health problems for both pregnant women and unborn babies worldwide. However, the underlying causes of preeclampsia are not fully understood, leading to limited effective treatments. The goal of this study is to enhance our knowledge of its causes, devise prevention strategies, and develop treatments. METHODS: We performed a systematic literature search. Six models regarding the pathogenesis of preeclampsia are discussed in this review. RESULTS: This review focuses on the latest advancements in understanding preeclampsia's origins. Preeclampsia is a complex condition caused by various factors, processes, and pathways. Reduced blood flow and oxygen to the uterus and placenta, heightened inflammatory reactions, immune imbalances, altered genetic changes, imbalanced blood vessel growth factors, and disrupted gut bacteria may contribute to its development. CONCLUSION: Preeclampsia is thought to result from the interplay of these factors.


Assuntos
Pré-Eclâmpsia , Gravidez , Feminino , Humanos , Placenta/metabolismo , Útero/irrigação sanguínea
7.
Drug Dev Res ; 85(2): e22169, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38477422

RESUMO

Neutrophils are a crucial component of the innate immune system and play a pivotal role in various physiological processes. From a physical perspective, hitchhiking is considered a phenomenon of efficient transportation. The combination of neutrophils and hitchhikers has given rise to effective delivery systems both in vivo and in vitro, thus neutrophils hitchhiking become a novel approach to disease treatment. This article provides an overview of the innovative and feasible application of neutrophils as drug carriers. It explores the mechanisms underlying neutrophil function, elucidates the mechanism of drug delivery mediated by neutrophil-hitchhiking, and discusses the potential applications of this strategy in the treatment of cancer, immune diseases, inflammatory diseases, and other medical conditions.


Assuntos
Nanopartículas , Neoplasias , Humanos , Neutrófilos , Sistemas de Liberação de Medicamentos , Portadores de Fármacos , Nanopartículas/uso terapêutico
8.
Opt Express ; 31(26): 43362-43371, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38178431

RESUMO

To break through the limitations of the classical sine condition, a multi-field cosine condition (MCC) is proposed in this paper. Building on this condition, a design method for wide field-of-view (FOV) freeform aplanatic systems is also proposed. This design method ensures that the optical system meets the MCC by correcting the mapping relationships of rays that originate from different apertures on both the object and image sides of the optical system. Using this method, we have successfully designed a chromatic-aberration-free and unobstructed freeform off-axis reflective microscope objective that is characterized by a wide FOV, an extensive spectral working range, and an extended working distance. The objective, which comprises only three freeform mirrors, has a numerical aperture (NA) of 0.4, magnification of 20×, an FOV of 2 mm × 2 mm, and an extended working distance of up to 60 mm. The objective demonstrates imaging quality close to the diffraction limit across the visible band to the short-wave infrared band (0.4-3 µm). When compared with a transmission-type wide-field microscope objective with identical NA and magnification properties, the reflective microscope objective nearly triples the FOV.

9.
Chemistry ; 29(30): e202300446, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-36883663

RESUMO

Quantum chemical calculations using ab initio methods at the MRCI+Q(6,8)/def2-QZVPP and CCSD(T)/def2-QZVPP levels as well as density functional theory are reported for the diatomic molecules AeB- and isoelectronic AeC (Ae=Ca, Sr, Ba). The boride anions AeB- have an electronic triplet (3 Σ- ) ground state. The quintet (5 Σ- ) state is 5.8-12.3 kcal/mol higher in energy and the singlet (1 Δ) state is 13.1-15.3 kcal/mol above the triplet. The isoelectronic AeC molecules are also predicted to have a low-lying triplet (3 Σ- ) state but the quintet (5 Σ- ) state is only 2.2 kcal/mol (SrC) and 2.9 kcal/mol (CaC) above the triplet state. The triplet (3 Σ- ) and quintet (5 Σ- ) states of BaC are nearly isoenergetic. All systems have rather strong bonds. The calculated bond dissociation energies of the triplet (3 Σ- ) state are between De =38.3-41.7 kcal/mol for AeB- and De =49.4-57.5 kcal/mol for AeC. The barium species have always the strongest bonds whereas the calcium and strontium compounds have similar BDEs. The bonding analysis indicates that there is little charge migration in AeB- in the direction Ae→B- where the alkaline earth atoms carry positive charges between 0.09 e-0.22 e. The positive charges at the Ae atoms are much larger in AeC where the charge migration Ae→C is between 0.90 e-0.91 e. A detailed analysis of the interatomic interactions with the EDA-NOCV method shows that all diatomic species AeB- and AeC are built from dative interactions between Ae (1 S, ns2 ) and B- or C (3 P, 2 s2 2pπ 1 2pπ' 1 ). The eventually formed bonds in AeC are better described in terms of interactions between the ions Ae+ (2 S, ns1 )+C- (4 S, 2 s2 2pπ 1 2pπ' 1 2pσ 1 ). Inspection of the orbital interactions suggests that the alkaline earth atoms Ca, Sr, Ba use mainly their (n-1)d AOs besides the (n)s AOs for the covalent bonds. This creates a second energetically low-lying σ-bonding MO in the molecules, which feature valence orbitals with the order ϕ1 (σ-bonding)<ϕ2 (σ-bonding)<ϕ3 (degenerate π-bonding). All four occupied valence MOs of AeB- and AeC are bonding orbitals. Since the degenerate π orbitals ϕ3 are only singly occupied, the formal bond order is three.

10.
Chemphyschem ; 24(15): e202300257, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37309297

RESUMO

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.

11.
Helicobacter ; 28(5): e13007, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37452727

RESUMO

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.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Mídias Sociais , Humanos , Helicobacter pylori/genética , Fonte de Informação , China , Reprodutibilidade dos Testes
12.
Phys Chem Chem Phys ; 25(2): 1105-1113, 2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36514964

RESUMO

Because of the electron deficiency of boron, a triangular network with planar hexacoordination is the most common structural and bonding property for isolated boron clusters and two-dimensional (2D) boron sheets. However, this network is a rule-breaking structure and bonding case for all other main-group elements. Herein, the Be2M (M = Al and Ga) 2D monolayer with P6/mmm space group was found to be the lowest-energy structure with planar hexacoordinate Be/Al/Ga motifs. More interestingly, Be2Al and Be2Ga were observed to be intrinsic phonon-mediated superconductors with a superconducting critical temperature (Tc) of 5.9 and 3.6 K, respectively, where compressive strain could further enhance their Tc. The high thermochemical and kinetic stability of Be2M make a promising candidate for experimental realization, considering its high cohesive energy, absence of soft phonon modes, and good resistance to high temperature. Moreover, the feasibility of directly growing Be2M on the electride Ca2N substrate was further demonstrated, where its intriguing electronic and superconducting properties were well maintained in comparison with the freestanding monolayer. The Be2M monolayer with rule-breaking planar hexacoordinate motifs firmly pushes the ultimate connection of the "anti-van't Hoff/Le Bel" structure with promising physical properties.

13.
Phys Chem Chem Phys ; 25(30): 20759, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37489011

RESUMO

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.

14.
BMC Cardiovasc Disord ; 23(1): 574, 2023 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-37990168

RESUMO

PURPOSE: The goal of blood pressure (BP) control will be lower when hypertensive patients have comorbidities that can affect the risk of cardiovascular diseases. But, the goal of BP control for hypertensive patients coexistent with obstructive sleep apnea (OSA) is not discussed, which is a special population at high risk of cardiovascular diseases. PATIENTS AND METHODS: Using data from a retrospective study(Urumqi Research on Sleep Apnea and Hypertension (UROSAH) study, we enrolled 3267 participants who were diagnosed with hypertension and performed polysomnography during 2011-2013 to explore the association between BP control and long-term major adverse cardiovascular and cerebrovascular event (MACCE). Outcomes of interest was the levels of BP control, MACCE, cardiac event and cerebrovascular event. Then we calculated the cumulative incidence of MACCE and performed Cox proportional hazards with stepwise models. RESULTS: 379 of 3267 patients experienced MACCE during a median follow-up of 7.0 years. After full risk adjustment, BP control of 120-139/80-89mmHg was associated with the lowest risk of cerebrovascular event (HR: 0.53, 95%CI:0.35-0.82) rather than MACCE and cardiac event in the total cohort. The association did not change much in patients with OSA. When the SBP and DBP were discussed separately, the SBP control of 120-139mmHg or < 120mmHg was associated with the decreased incidence of MACCE and cerebrovascular event. When DBP control < 80 mm Hg, the risk of cerebrovascular event showed 54% decrease [(HR:0.46, 95%CI: 0.25-0.88)] in patients with hypertension and OSA. CONCLUSION: In this retrospective study, antihypertensive-drug-induced office and home BP control at 120-139/80-89mmHg showed possible beneficial effect on incident MACCE. However, current results need to be verified in future studies.


Assuntos
Doenças Cardiovasculares , Hipertensão , Apneia Obstrutiva do Sono , Humanos , Pressão Sanguínea , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/complicações , Estudos Retrospectivos , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/epidemiologia , Fatores de Risco
15.
Bioorg Chem ; 140: 106779, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37579621

RESUMO

Blocking the PI3K pathway has been recognized as a promising strategy for cancer therapy. Herein, we report the discovery of novel PI3K inhibitors utilizing 7-azaindole-based fragment-oriented growth. Among them, compound FD2056 stands out as the most promising candidate, maintaining potent inhibitory activity against PI3K and enhanced CDK2 inhibition, and showing moderate selectivity among 108 kinases. In cellular assays, the inhibitor FD2056 demonstrated superior anti-proliferative profiles over reference compounds against TNBC cells and significantly increased apoptosis of MDA-MB-231 cells in a dose-dependent manner. Moreover, FD2056 showed more efficacious anti-TNBC activity than the corresponding drugs BKM120 and CYC202 at an oral dose of 15 mg/kg in the MDA-MB-231 xenograft model, inhibiting tumor growth by 43% with no observable toxic effects. All these results suggest that FD2056 has potential for further development as a promising anticancr compound, and co-targeting PI3K and CDK2 pathways may provide an alternative therapeutic strategy for the treatment of TNBC.


Assuntos
Fosfatidilinositol 3-Quinases , Neoplasias de Mama Triplo Negativas , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Proliferação de Células , Apoptose , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Linhagem Celular Tumoral , Quinase 2 Dependente de Ciclina
16.
J Chem Phys ; 159(5)2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37526162

RESUMO

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.

17.
Int Heart J ; 64(6): 970-978, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37967976

RESUMO

Hypertensive patients with snoring and elevated plasma homocysteine levels are common. When these factors are combined, the risk of coronary heart disease (CHD) is high. Herein, we developed and validated an easy-to-use nomogram to predict high-risk CHD in snoring hypertensive patients with elevated plasma homocysteine.Snoring patients (n = 1,962) with hyperhomocysteinemia and hypertension were divided into training (n = 1,373, 70%) and validation (n = 589, 30%) sets. We extracted CHD predictors using multivariate Cox regression analysis, then constructed a nomogram model. Internal validation using 1,000 bootstrap resampling was performed to assess the consistency and discrimination of the predictive model using the area under the receiver operating characteristic curve (AUC) and calibration plots.We constructed a nomogram model with the extracted predictors, including age, waist-height ratio, smoking, and low-density lipoprotein cholesterol levels. The AUCs of the training and validation cohorts at 80 months were 0.735 (95% CI: 0.678-0.792) and 0.646 (95% CI: 0.547-0.746), respectively. The consistency between the observed CHD survival and the probability of CHD survival in the training and validation sets was acceptable based on the calibration plots. A total of more than 151 points in the nomogram can be used in the identification of high-risk patients for CHD among snoring hypertensive patients with elevated plasma homocysteine.We developed a CHD risk prediction model for snoring hypertension patients with hyperhomocysteinemia. Our findings provide a useful clinical tool for the rapid identification of high-risk CHD at an early stage.


Assuntos
Doença das Coronárias , Hiper-Homocisteinemia , Hipertensão , Humanos , Hiper-Homocisteinemia/complicações , Hiper-Homocisteinemia/diagnóstico , Hiper-Homocisteinemia/epidemiologia , Ronco/epidemiologia , Doença das Coronárias/complicações , Doença das Coronárias/diagnóstico , Doença das Coronárias/epidemiologia , Hipertensão/complicações , Hipertensão/epidemiologia , Homocisteína , Nomogramas
18.
Chem Res Chin Univ ; 39(1): 42-60, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36687211

RESUMO

The development of stimuli-responsive nanodevices with high efficiency and specificity is very important in biosensing, drug delivery, and so on. DNAzymes are a class of DNA molecules with the specific catalytic activity. Owing to their unique catalytic activity and easy design and synthesis, the construction and application of DNAzymes-based nanodevices have attracted much attention in recent years. In this review, the classification and properties of DNAzyme are first introduced. The construction of several common kinds of DNAzyme-based nanodevices, such as DNA motors, signal amplifiers, and logic gates, is then systematically summarized. We also introduce the application of DNAzyme-based nanodevices in sensing and therapeutic fields. In addition, current limitations and future directions are discussed.

19.
Clin Endocrinol (Oxf) ; 94(1): 3-11, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32810877

RESUMO

OBJECTIVE: Metabolic syndrome (MetS) is a frequent clinical condition in hypertension patients and is more frequently reported in primary aldosteronism (PA). This study is aimed at investigating the prevalence of MetS and its components in the two major types of patients with adrenal venous sampling (AVS)-confirmed unilateral PA and bilateral PA. DESIGN AND PATIENTS: This was a retrospective cross-section study. We analysed metabolic parameters from 169 PA patients subtyped by AVS, including 85 unilateral PA patients and 84 bilateral PA patients, and we also included 169 non-PA patients matched for age and sex. RESULTS: Patients with unilateral PA had higher concentrations of aldosterone and lower serum potassium than patients with bilateral PA. However, patients with bilateral PA had higher prevalence of MetS (79.8% vs 64.7%, P = .029), obesity (40.5% vs 24.7%, P = .029), dyslipidemia (72.6% vs 55.3%, P = .019) and hyperglycaemia (29.8% vs 16.5%, P = .040) than those with unilateral PA. Meanwhile, bilateral PA had higher BMI (27.55 ± 4.58 vs 25.57 ± 3.28 kg/m2 , P = .001), waist circumference (98.54 ± 11.44 vs 93.32 ± 10.64 cm, P = .003) and fasting plasma glucose (4.98 ± 1.16 vs 4.64 ± 0.93 mmol/L, P = .034). The logistic regression analysis also showed that bilateral PA was associated with the presence of MetS after adjustment for age, sex and duration of hypertension. CONCLUSIONS: Patients with bilateral PA have a higher prevalence of MetS than those with unilateral PA, despite unilateral PA patients exhibiting higher concentrations of aldosterone and lower serum potassium, suggesting that unilateral PA and bilateral PA may have differing mechanisms of MetS.


Assuntos
Hiperaldosteronismo , Síndrome Metabólica , Glândulas Suprarrenais , Aldosterona , Humanos , Hiperaldosteronismo/complicações , Hiperaldosteronismo/epidemiologia , Síndrome Metabólica/epidemiologia , Prevalência , Estudos Retrospectivos
20.
Chemphyschem ; 22(19): 1996-2003, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34396650

RESUMO

The triply bonded heavier main-group compounds have a textbook trans-bent geometry, in contrast to a familiar linear form found for the lightest analogues. Strikingly, the unexpected linear group 13 E≡E triple bonds were herein found in the D4h -symmetry E2 Li6 2+ clusters, and they possess a large barrier (>18.0 kcal/mol) towards the dissociation of Li+ . The perfectly surrounded Li4 motifs and two linear coordinated Li atoms strongly suppress the increasing nonbonded electron density of heavier E atoms, making two degenerate π bonds and one multi-center σ bond in linear heavier main-group triple bonds. The surrounding Li6 motifs not only creates an effective electronic structure to form a linear E≡E triple bond, but the resulting electrostatic interactions account for the highly stable global E2 Li6 2+ clusters.

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