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1.
J Comput Chem ; 45(31): 2678-2689, 2024 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-39135268

RESUMO

The two-dimensional (2D) monolayer material MoSi2N4 was successfully synthesized in 2020[Hong et al., Science 369, 670, (2020)], exhibiting a plethora of new phenomena and unusual properties, with good stability at room temperature. However, MA2Z4 family monolayer materials involve primarily transition metal substitutions for M atoms. In order to address the research gap on lanthanide and actinide MA2Z4 materials, this work conducts electronic structure calculations on novel 2D MSi2N4 (M = La, Eu) monolayer materials by employing first-principles methods and CASTEP. High carrier mobility is discovered in the indirect bandgap semiconductor 2D LaSi2N4 monolayer (~5400 cm2 V-1 s-1) and in the spin (spin-down channel) carrier mobility of the half-metallic ferromagnetic EuSi2N4 monolayer (~2800 cm2 V-1 s-1). EuSi2N4 monolayer supplements research on spin carrier mobility in half-metallic ferromagnetic monolayer materials at room temperature and possesses a magnetic moment of 5 µB, which should not be underestimated. Furthermore, due to the unique electronic band structure of EuSi2N4 monolayer (with the spin-up channel exhibiting metallic properties and the spin-down channel exhibiting semiconductor properties), it demonstrates a 100% spin polarization rate, presenting significant potential applications in fields such as magnetic storage, magnetic sensing, and spintronics.

2.
J Comput Chem ; 45(14): 1087-1097, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38243618

RESUMO

A series of pentagonal bipyramidal anionic germanium clusters doped with heavy rare earth elements, REGe 6 - (RE = Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu), have been identified at the PBE0/def2-TZVP level using density functional theory (DFT). Our findings reveal that the centrally doped pentagonal ring structure demonstrates enhanced stability and heightened aromaticity due to its uniform bonding characteristics and a larger charge transfer region. Through natural population analysis and spin density diagrams, we observed a monotonic decrease in the magnetic moment from Gd to Yb. This is attributed to the decreasing number of unpaired electrons in the 4f orbitals of the heavy rare earth atoms. Interestingly, the system doped with Er atoms showed lower stability and anti-aromaticity, likely due to the involvement of the 4f orbitals in bonding. Conversely, the systems doped with Gd and Tb atoms stood out for their high magnetism and stability, making them potential building blocks for rare earth-doped semiconductor materials.

3.
Phys Chem Chem Phys ; 26(42): 27106-27115, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39431706

RESUMO

Numerous boron-based molecular fluxional models, such as the Wankel motor, tank treads B11- and B10C, and the Earth-Moon system Be6B11-, have been widely recognized for their potential to develop molecular machines. From a series of tin-doped boron clusters SnBn- (n = 5-14), the half-sandwich structure SnB7- is found to possess high relative energy stability, and a HOMO-LUMO gap of 4.33 eV. This structure exhibits valence electron orbitals reminiscent of σ-π double aromatic compounds. The incorporation of tin effectively fills the doubly vacant π orbitals of its parent triplet B7-, thereby enhancing both magnetic shielding capabilities and range. Thermal bath tests demonstrate its significant dynamic stability, as the kinetic energy provided by thermal baths below 3800 K remains insufficient to disrupt its inherent elasticity. Additionally, transition state searches and intrinsic reaction coordinate analyses confirm that the tin atom migrates from the centre to the edge of the boron ligand surface, a phenomenon that can be observed in high-temperature thermal bath simulations. This fluxional behaviour provides insights for constructing novel molecular machine models.

4.
Phys Chem Chem Phys ; 26(4): 2986-2994, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38163990

RESUMO

Rare earth elements have high chemical reactivity, and doping them into semiconductor clusters can induce novel physicochemical properties. The study of the physicochemical mechanisms of interactions between rare earth and tin atoms will enhance our understanding of rare earth functional materials from a microscopic perspective. Hence, the structure, electronic characteristics, stability, and aromaticity of endohedral cages MSn16- (M = Sc, Y, La) have been investigated using a combination of the hybrid PBE0 functional, stochastic kicking, and artificial bee colony global search technology. By comparing the simulated results with experimental photoelectron spectra, it is determined that the most stable structure of these clusters is the Frank-Kasper polyhedron. The doping of atoms has a minimal influence on density of states of the pure tin system, except for causing a widening of the energy gap. Various methods such as ab initio molecular dynamics simulations, the spherical jellium model, adaptive natural density partitioning, localized orbital locator, and electron density difference are employed to analyze the stability of these clusters. The aromaticity of the clusters is examined using iso-chemical shielding surfaces and the gauge-including magnetically induced currents. This study demonstrates that the stability and aromaticity of a tin cage can be systematically adjusted through doping.

5.
J Phys Chem A ; 128(28): 5459-5472, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-38973649

RESUMO

In this study, we employ density functional theory along with the artificial bee colony algorithm for cluster global optimization to explore the low-lying structures of TeBnq (n = 3-16, q = 0, -1). The primary focus is on reporting the structural properties of these clusters. The results reveal a consistent doping pattern of the tellurium atom onto the in-plane edges of planar or quasi-planar boron clusters in the most energetically stable isomers. Additionally, we simulate the photoelectron spectra of the cluster anions. Through relative stability analysis, we identify three clusters with magic numbers -TeB7-, TeB10, and TeB12. The aromaticity of these clusters is elucidated using adaptive natural density partitioning (AdNDP) and magnetic properties analysis. Notably, TeB7- exhibits a perfect σ-π doubly aromatic structure, while TeB12 demonstrates strong island aromaticity. These findings significantly contribute to our understanding of the structural and electronic properties of these clusters.

6.
Ethn Health ; 29(4-5): 435-446, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38682471

RESUMO

OBJECTIVES: This study aimed to examine ethnic disparities in the prevalence of diabetes and its association with sleep disorders among the older adults Han and ethnic minority (Bai, Ha Ni, and Dai) population in rural southwest China. METHODS: A cross-sectional survey of 5,642 was conducted among the rural southwest population aged ≥60 years, consisting of a structured interview and measurement of fasting blood glucose, height, weight, and waist circumference. The Pittsburgh Sleep Quality Index (PSQI) was used to assess sleep quality. RESULTS: The overall prevalence of diabetes and sleep disorder was 10.2% and 40.1%, respectively. Bai participants had the highest prevalence of diabetes (15.9%) and obesity (9.9%)(P < 0.01), while Ha Ni participants had the lowest prevalence of diabetes (5.1%) and obesity (3.4%)(P < 0.01). The highest prevalence of sleep disorder (48.4%) was recorded in Bai participants, while Dai participants had the lowest prevalence of sleep disorder (25.6%)(P < 0.01). In all four studied ethnicities, females had a higher prevalence of sleep disorder than males (P < 0.01), and the prevalence of sleep disorder increased with age (P < 0.01). The results of multivariate logistic regression analysis indicated older adults with sleep disorder had a risk of developing diabetes (P < 0.05). Moreover, the higher educational level, family history of diabetes, and obesity were the main risk factors for diabetes in participants (P < 0.01). CONCLUSION: There are stark ethnic disparities in the prevalence of diabetes and sleep disorders in southwest China. Future diabetes prevention and control strategies should be tailored to address ethnicity, and improving sleep quality may reduce the prevalence of diabetes.


Assuntos
Diabetes Mellitus , População Rural , Transtornos do Sono-Vigília , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , China/epidemiologia , China/etnologia , Estudos Transversais , Diabetes Mellitus/etnologia , Diabetes Mellitus/epidemiologia , Etnicidade/estatística & dados numéricos , Disparidades nos Níveis de Saúde , Obesidade/etnologia , Obesidade/epidemiologia , Prevalência , População Rural/estatística & dados numéricos , Transtornos do Sono-Vigília/etnologia , Transtornos do Sono-Vigília/epidemiologia , População do Leste Asiático
7.
Molecules ; 29(13)2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38999190

RESUMO

This paper systematically investigates the structure, stability, and electronic properties of niobium carbide clusters, NbmCn (m = 5, 6; n = 1-7), using density functional theory. Nb5C2 and Nb5C6 possess higher dissociation energies and second-order difference energies, indicating that they have higher thermodynamic stability. Moreover, ab initio molecular dynamics (AIMD) simulations are used to demonstrate the thermal stability of these structures. The analysis of the density of states indicates that the molecular orbitals of NbmCn (m = 5, 6; n = 1-7) are primarily contributed by niobium atoms, with carbon atoms having a smaller contribution. The composition of the frontier molecular orbitals reveals that niobium atoms contribute approximately 73.1% to 99.8% to NbmCn clusters, while carbon atoms contribute about 0.2% to 26.9%.

8.
Molecules ; 29(8)2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38675512

RESUMO

The geometrical structures, relative stabilities, and electronic and magnetic properties of niobium carbon clusters, Nb7Cn (n = 1-7), are investigated in this study. Density functional theory (DFT) calculations, coupled with the Saunders Kick global search, are conducted to explore the structural properties of Nb7Cn (n = 1-7). The results regarding the average binding energy, second-order difference energy, dissociation energy, HOMO-LUMO gap, and chemical hardness highlight the robust stability of Nb7C3. Analysis of the density of states suggests that the molecular orbitals of Nb7Cn primarily consist of orbitals from the transition metal Nb, with minimal involvement of C atoms. Spin density and natural population analysis reveal that the total magnetic moment of Nb7Cn predominantly resides on the Nb atoms. The contribution of Nb atoms to the total magnetic moment stems mainly from the 4d orbital, followed by the 5p, 5s, and 6s orbitals.

9.
Med Sci Monit ; 29: e939482, 2023 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-37421131

RESUMO

BACKGROUND Patients with insulin-resistant diabetes have the highest risk of kidney disease. The triglyceride glucose (TyG) index is considered a reliable and simple marker of insulin resistance. We studied the relationship between the TyG index, diabetic kidney disease (DKD), and related metabolic disorders in patients with type 2 diabetes. MATERIAL AND METHODS This retrospective study included a consecutive case series from January 2021 to October 2022 in the Department of Endocrinology at Hebei Yiling Hospital. In total, 673 patients with type 2 diabetes met the inclusion criteria. The TyG index was calculated by napierian logarithmic (ln) (fasting triglyceride×fasting glucose /2). Patient demographic and clinical indicators were obtained from medical records, and statistical analysis was conducted using SPSS version 23. RESULTS The TyG index was significantly related to metabolic indicators (low-density lipoprotein, high-density lipoprotein, alanine aminotransferase, plasma albumin, serum uric acid, triglyceride, and fasting glucose) and urine albumin (P<0.01) but not with serum creatinine and estimated glomerular filtration rate. In multiple regression analysis, an increase in the TyG index was revealed to be an independent risk factor for DKD (OR: 1.699, P<0.001). CONCLUSIONS The TyG index was independently related to DKD and related metabolic disorders; therefore, the TyG index can be used as an early sensitive target for clinical guidance in the treatment of DKD with insulin resistance.


Assuntos
Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Resistência à Insulina , Humanos , Diabetes Mellitus Tipo 2/complicações , Glucose , Estudos Retrospectivos , Triglicerídeos , Ácido Úrico , Glicemia/metabolismo , Biomarcadores , Fatores de Risco
10.
BMC Public Health ; 23(1): 603, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36997910

RESUMO

BACKGROUND: Diabetes has become a major public health problem in China. A better understanding of diabetes determinants and urban-rural differences is essential to crafting targeted diabetes prevention measures for the elderly living in both urban and rural areas. This study aimed to compare rural-urban differentials in prevalence and lifestyle determinants of pre-diabetes and diabetes among the elderly in southwest China. METHODS: A cross-sectional health interview and examination survey was conducted among individuals aged ≥ 60 years in both a rural and urban area of China. Anthropometric measurements, including height, weight, and waist circumference, as well as blood pressure and fasting blood glucose measurements were taken. Associated risk factors for pre-diabetes and diabetes were evaluated using multivariate logistic regression analysis. RESULTS: In total, 1,624 urban residents and 1,601 rural residents consented to participate in the study. The urban prevalence of pre-diabetes and diabetes (46.8% and 24.7%, respectively), was higher than the rural prevalence (23.4% and 11.0%, respectively, P<0.01). Urban elderly participants had markedly higher prevalence of obesity, central obesity, and physical inactivity than their rural counterparts (15.3%, 76.0%, and 9.2% vs. 4.6%, 45.6%, and 6.1%, P<0.01). In contrast, rural elderly adults had higher prevalence of smoking than urban ones (23.2% vs. 17.2%, P<0.01). Obese (OR 1.71, 95% CI 1.27-2.30 vs. OR 1.73, 95% CI 1.30-3.28) and centrally obese participants (OR 1.59, 95% CI 1.18-2.15 vs. OR 1.83, 95% CI 1.32-2.54) were more likely to suffer from diabetes in both urban and rural regions. Furthermore, urban current smokers had a higher probability of suffering from diabetes (OR 1.58, 95% CI 1.11-2.25), while hypertension was positively associated with the prevalence of diabetes in the rural area (OR 2.13, 95% CI 1.54-2.95). Obese participants in the rural area were more likely to suffer from pre-diabetes (OR 2.50, 95% CI 1.53-4.08), while physical inactivity was positively associated with prevalence of pre-diabetes in the urban area (OR 1.95, 95% CI 1.37-2.80). CONCLUSION: Pre-diabetes and diabetes are more prevalent among urban older adults than their rural counterparts in southwest China. The identified rural-urban differentials of lifestyle factors have significant impacts on prevalence of pre-diabetes and diabetes. Thus, tailored lifestyle interventions are needed to improve diabetes prevention and management among the elderly in southwest China.


Assuntos
Diabetes Mellitus , Hipertensão , Estado Pré-Diabético , Idoso , Humanos , Estado Pré-Diabético/epidemiologia , Estado Pré-Diabético/complicações , Prevalência , Estudos Transversais , Diabetes Mellitus/epidemiologia , Fatores de Risco , Hipertensão/epidemiologia , Hipertensão/etiologia , Obesidade/epidemiologia , Obesidade/complicações , Estilo de Vida , China/epidemiologia , População Rural , População Urbana
11.
Molecules ; 28(13)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37446733

RESUMO

The growth behavior, stability, electronic and magnetic properties of the Gd2Sin- (n = 3-12) clusters are reported, which are investigated using density functional theory calculations combined with the Saunders 'Kick' and the Artificial Bee Colony algorithm. The lowest-lying structures of Gd2Sin- (n = 3-12) are all exohedral structures with two Gd atoms face-capping the Sin frameworks. Results show that the pentagonal bipyramid (PB) shape is the basic framework for the nascent growth process of the present clusters, and forming the PB structure begins with n = 5. The Gd2Si5- is the potential magic cluster due to significantly higher average binding energies and second order difference energies, which can also be further verified by localized orbital locator and adaptive natural density partitioning methods. Moreover, the localized f-electron can be observed by natural atomic orbital analysis, implying that these electrons are not affected by the pure silicon atoms and scarcely participate in bonding. Hence, the implantation of these elements into a silicon substrate could present a potential alternative strategy for designing and synthesizing rare earth magnetic silicon-based materials.


Assuntos
Algoritmos , Silício , Proliferação de Células , Ciclo Celular , Elétrons
12.
Mol Med ; 28(1): 135, 2022 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-36401167

RESUMO

BACKGROUND: Rheumatoid arthritis (RA) is a complex autoimmune disease with multiple etiological factors, among which aberrant memory CD4 T cells activation plays a key role in the initiation and perpetuation of the disease. SIGIRR (single immunoglobulin IL-1R-related receptor), a member of the IL-1 receptor (ILR) family, acts as a negative regulator of ILR and Toll-like receptor (TLR) downstream signaling pathways and inflammation. The aim of this study was to investigate the potential roles of SIGIRR on memory CD4 T cells in RA and the underlying cellular and molecular mechanisms. METHODS: Single-cell transcriptomics and bulk RNA sequencing data were integrated to predict SIGIRR gene distribution on different immune cell types of human PBMCs. Flow cytometry was employed to determine the differential expression of SIGIRR on memory CD4 T cells between the healthy and RA cohorts. A Spearman correlation study was used to determine the relationship between the percentage of SIGIRR+ memory CD4 T cells and RA disease activity. An AIA mouse model (antigen-induced arthritis) and CD4 T cells transfer experiments were performed to investigate the effect of SIGIRR deficiency on the development of arthritis in vivo. Overexpression of SIGIRR in memory CD4 T cells derived from human PBMCs or mouse spleens was utilized to confirm the roles of SIGIRR in the intracellular cytokine production of memory CD4 T cells. Immunoblots and RNA interference were employed to understand the molecular mechanism by which SIGIRR regulates TNF-α production in CD4 T cells. RESULTS: SIGIRR was preferentially distributed by human memory CD4 T cells, as revealed by single-cell RNA sequencing. SIGIRR expression was substantially reduced in RA patient-derived memory CD4 T cells, which was inversely associated with RA disease activity and related to enhanced TNF-α production. SIGIRR-deficient mice were more susceptible to antigen-induced arthritis (AIA), which was attributed to unleashed TNF-α production in memory CD4 T cells, confirmed by decreased TNF-α production resulting from ectopic expression of SIGIRR. Mechanistically, SIGIRR regulates the IL-1/C/EBPß/TNF-α signaling axis, as established by experimental evidence and cis-acting factor bioinformatics analysis. CONCLUSION: Taken together, SIGIRR deficiency in memory CD4 T cells in RA raises the possibility that receptor induction can target key abnormalities in T cells and represents a potentially novel strategy for immunomodulatory therapy.


Assuntos
Artrite Reumatoide , Fator de Necrose Tumoral alfa , Humanos , Camundongos , Animais , Linfócitos T CD4-Positivos/metabolismo , Receptores de Interleucina-1/genética , Receptores de Interleucina-1/metabolismo , Transdução de Sinais/fisiologia , Artrite Reumatoide/genética
13.
Appl Microbiol Biotechnol ; 106(4): 1615-1631, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35129656

RESUMO

Rhubarb, a traditional herb, has been used in clinical practice for hundreds of years to cure constipation, but its mechanism is still not clear enough. Currently, growing evidence suggests that intestinal flora might be a potential target for the treatment of constipation. Thus, the aim of this study was to clarify the laxative effect of rhubarb via systematically analyzing the metagenome and metabolome of the gut microbiota. In this study, the laxative effects of rhubarb were investigated by loperamide-induced constipation in rats. The gut microbiota was determined by high-throughput sequencing of 16S rRNA gene. Ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry was used for fecal metabolomics analysis. The data showed that rhubarb could significantly shorten gastrointestinal transit time, increase fecal water content and defecation frequency, improve gastrointestinal hormone disruption, and protect the colon mucus layer. Analysis of 16S rRNA gene sequencing indicated that rhubarb could improve the disorder of intestinal microbiota in constipated rats. For example, beneficial bacteria such as Ligilactobacillus, Limosilalactobacillus, and Prevotellaceae UCG-001 were remarkably increased, and pathogens such as Escherichia-Shigella were significantly decreased after rhubarb treatment. Additionally, the fecal metabolic profiles of constipated rats were improved by rhubarb. After rhubarb treatment, metabolites such as chenodeoxycholic acid, cholic acid, prostaglandin F2α, and α-linolenic acid were markedly increased in constipation rats; in contrast, the metabolites such as lithocholic acid, calcidiol, and 10-hydroxystearic acid were notably reduced in constipation rats. Moreover, correlation analysis indicated a close relationship between intestinal flora, fecal metabolites, and biochemical indices associated with constipation. In conclusion, the amelioration of rhubarb in constipation might modulate the intestinal microflora and its metabolism. Moreover, the application of fecal metabolomics could provide a new strategy to uncover the mechanism of herbal medicines.Key points• Rhubarb could significantly improve gut microbiota disorder in constipation rats.• Rhubarb could markedly modulate the fecal metabolite profile of constipated rats.


Assuntos
Medicamentos de Ervas Chinesas , Microbioma Gastrointestinal , Rheum , Animais , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Fezes/microbiologia , Laxantes/análise , Laxantes/farmacologia , Laxantes/uso terapêutico , RNA Ribossômico 16S/genética , Ratos , Rheum/química
14.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 53(1): 127-132, 2022 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-35048612

RESUMO

OBJECTIVE: To establish a 14-color flow cytometry protocol for the examination of leukocyte subsets in human peripheral blood. METHODS: We used cell membrane surface antibodies CD45, CD3, CD4, CD8, CD19, CD56, CD16, CD14, CD25, CD127, HLA-DR, CD123, CD11c and nucleus staining dye DAPI to establish a 14-color flow cytometry assay to determine the major cell subsets in human peripheral blood. We collected peripheral blood specimens from healthy volunteers to test for antibody titers and optimal photomultiplier tube (PMT) voltage, and to conduct single-color staining and fluorescence minus one control staining. After determining the test method and test conditions, the peripheral blood samples of 18 healthy volunteers were analyzed. RESULTS: According to the cell classification and staining index, optimal antibody mass concentrations selected were as follows: CD25 and CD127 at 8.0 µg/mL, CD45, CD3, CD14 and CD123 at 4.0 µg/mL, CD8, CD19, CD56, CD16, HLA-DR and CD11c at 2.0 µg/mL, CD4 at 1.0 µg/mL and DAPI at 0.1 µg/mL. The detection voltages for CD45, CD3, CD4, CD8, CD19, CD56, CD16, CD14, CD25, CD127, HLA-DR, CD123, CD11c and DAPI were 450 V, 410 V, 400 V, 550 V, 405 V, 500 V, 520 V, 550 V, 550 V, 400 V, 450 V, 400 V, 580 V, and 300 V, respectively. The appropriate fluorescence compensation was determined by single-color staining and fluorescence minus one controls. The 14-color flow cytometry panel was established to analyze the main subsets of leukocytes in human peripheral blood, and peripheral blood samples from 18 healthy adults were examined, obtaining the percentages of each subset of peripheral blood leukocytes and the immunophenotypes of the main subsets. CONCLUSION: We established a 14-color panel for determining leukocyte subsets in human peripheral blood by flow cytometry, which produced stable and reliable results and was easy to operate.


Assuntos
Leucócitos , Subpopulações de Linfócitos , Contagem de Células , Citometria de Fluxo , Humanos , Imunofenotipagem
15.
J Chem Phys ; 154(20): 204302, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34241172

RESUMO

A systematic structure and property investigation of MnGen - (n = 3-14) was conducted by means of density functional theory coupled with mass-selected anion photoelectron spectroscopy. This combined theoretical and experimental study allows global minimum and coexistence structures to be identified. It is found that the pentagonal bipyramid shape is the basic framework for the nascent growth process of MnGen - (n = 3-10), and from n = 10, the endohedral structures can be found. For n = 12, the anion MnGe12 - cluster probably includes two isomers: a major isomer with a puckered hexagonal prism geometry and a minor isomer with a distorted icosahedron geometry. Specifically, the puckered hexagonal prism isomer follows the Wade-Mingos rules and can be suggested as a new kind of superatom with the magnetic property. Furthermore, the results of adaptive natural density partitioning and deformation density analyses suggest a polar covalent interaction between Ge and Mn for endohedral clusters of MnGe12 -. The spin density and natural population analysis indicate that MnGen - clusters have high magnetic moments localized on Mn. The density of states diagram visually shows the significant spin polarization for endohedral structures and reveals the weak interaction between the Ge 4p orbital and the 4s, 3d orbitals of Mn.

16.
Zhongguo Zhong Yao Za Zhi ; 46(18): 4721-4729, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34581081

RESUMO

In this study, we studied the solubility and permeability of matrine, oxymatrine, sophoridine, and oxysophocarpine, four alkaloids in the Mongolian herbal medicine Sophorae Flavescentis Radix, and evaluated the absorption mechanism with the Caco-2 cell model, so as to provide a basis for the new drug development and efficacy evaluation of Sophorae Flavescentis Radix. The results showed that all the four alkaloids had high solubility and high permeability and can be well absorbed, belonging to the class-I drugs of Biopharmaceutical Classification System(BCS). The absorption(AP→BL) and excretion(BL→AP) of matrine and oxymatrine were not affected by the concentration while the absorption depended on P-gp protein. The absorption(AP→BL) and excretion(BL→AP) of sophoridine and oxysophocarpine were positively related to the concentration and time, and the absorption process was independent from P-gp protein. The results provide scientific reference and an experimental basis for the development of Mongolian medical prescriptions containing Sophorae Flavescentis Radix.


Assuntos
Alcaloides , Produtos Biológicos , Medicamentos de Ervas Chinesas , Sophora , Células CACO-2 , Medicina Herbária , Humanos
17.
Zhongguo Zhong Yao Za Zhi ; 46(11): 2843-2851, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34296584

RESUMO

The quality control of Epimedii Folium, composed of diverse constituents, is single at present. In view of this, an eva-luation method of 13 chemical constituents based on quantitative analysis of multi-components by single marker(QAMS) was established to further explore the composition differences of raw products and alcohol extracts in different batches and the influence of alcohol extraction on the composition, so as to provide a reference for improving the quality evaluation and control of Epimedii Folium. The fingerprints of different batches of Epimedii Folium were constructed by ultra-high performance liquid chromatography(UPLC) to evaluate the inter-batch consistency. The changes of the flavonoids in Epimedii Folium during alcohol extraction were analyzed based on determined levels and heat map, and the reasons for the changes were preliminarily discussed. With icariin, the quality control component recorded in the Chinese Pharmacopoeia, as the internal reference, the stability of the relative correction factors of chemical components under different conditions was investigated to obtain the relative correction factors. Then the determination results of QAMS and the external standard method were compared to verify the accuracy of QAMS. The results revealed that all batches of Epimedii Folium met the requirements specified in the Chinese Pharmacopoeia, and the fingerprints of Epimedii Folium from the same place of origin exhibited a high similarity. Raw products and alcohol extracts of Epimedii Folium could be clearly distinguished by prenylated flavonoids, which are potential biomarkers for quality control. Additionally, the glycoside hydrolysis in the alcohol extraction was preliminarily explored. The QAMS method has good accuracy, durability, and repeatability in determining 13 chemical components in Epimedii Folium under different experimental conditions. No significant difference in the results obtained by the two methods was observed. This study can provide a reference for comprehensive, rapid and reasonable quality evaluation of Epimedii Folium.


Assuntos
Medicamentos de Ervas Chinesas , Biomarcadores , Cromatografia Líquida de Alta Pressão , Folhas de Planta
18.
Phys Chem Chem Phys ; 22(36): 20545-20552, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32966449

RESUMO

Lanthanide-doped silicon clusters have been extensively studied in the fields of optoelectronics, magnetism and nanomaterials during the last decade. Herein, systematic structure searches for typical neutral clusters of lanthanide-doped silicon clusters LnSin (n = 5, 10; Ln = Sm, Eu, Yb) have been performed by means of density functional theory coupled with the "stochastic kicking" global search technique. It is found that the Ln atom in LnSin prefers to locate on the surface of Sin to form an exohedral structure, and this exohedral configuration may dominate the nascent structure of LnSin. The spin density and Mulliken population analyses indicate that LnSin clusters possess remarkable magnetic moments (except for YbSin), which are mainly supplied by the Ln 4f electrons (except for Yb). Density of states visually shows the significant spin polarization for open-shell structures of SmSin and EuSin. As for the YbSin (n = 5, 10) system, it has a closed-shell electronic structure with a large HOMO-LUMO gap of 2.72 eV. Bonding analysis, including localized orbital locator and electron density difference, shows that the Si-Si covalent interaction and Sm-Si electrostatic interaction are important for the structural stability of LnSin.

19.
Clin Exp Pharmacol Physiol ; 47(8): 1333-1341, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32215933

RESUMO

The efficacy of dexmedetomidine in the prevention of postoperative delirium (POD) remains ambiguous, however, it has been used to reduce the incidence of delirium in elderly patients. Here, we conducted a meta-analysis study for assessing the effects of dexmedetomidine on POD among elderly patients following non-cardiac surgery. A systematic literature search was performed against the PubMed, EMBASE, Cochrane Library, and Web of Science databases, and all relevant literature published till November 30, 2019, were considered. Our analysis included 16 randomised controlled trials conducted with 4534 patients for exploring the effects of dexmedetomidine on POD in elderly patients following non-cardiac surgery. It was observed that the overall incidence of POD was significantly lower in the dexmedetomidine group than in the control group (risk ratio [RR] 0.51, 95% confidence interval [CI] 0.43-0.61, P < .01). Similar results were obtained from subgroup analysis upon comparison of the placebo (RR 0.52, 95% CI 0.41-0.66, P < .01, moderate quality of evidence), propofol-treated (RR 0.55, 95% CI 0.38-0.78, P < .01, low quality of evidence), and midazolam-treated (RR 0.38, 95% CI 0.20-0.71, P < .01, low quality of evidence) groups. Trial sequential analysis revealed that the cumulative z-value superseded the monitoring boundary and reached the required information size. However, patients who received dexmedetomidine had a higher incidence of bradycardia and hypotension. In conclusion, the meta-analysis revealed that dexmedetomidine appears to decrease the risk of POD in elderly patients following non-cardiac surgery. However, as some of the studies were heterogeneous and of low quality, high-quality trials are necessary for drawing more definitive conclusions.


Assuntos
Delírio/prevenção & controle , Dexmedetomidina/farmacologia , Complicações Pós-Operatórias/prevenção & controle , Idoso , Humanos
20.
J Public Health (Oxf) ; 42(2): 239-246, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-30860582

RESUMO

BACKGROUND: This study estimates the prevalence of five chronic non-communicable disease (NCDs) (hypertension, diabetes, CHD, COPD and stroke) and its multimorbidity, and examines the relationship between SES and lifestyle factors and multimorbidity among older adults in rural southwest China. METHODS: A cross-sectional survey of 4833 consenting adults aged ≥60 years was conducted in 2017. Data on the demographics, smoking, drinking, height, weight, blood pressure and fasting blood glucose were collected. RESULTS: Among the participants, the overall prevalence of hypertension, diabetes, stroke, COPD and CHD was 50.6, 10.2, 6.4, 5.4 and 5.5%, respectively, and of multimorbidity was 16.1%. Females had a higher prevalence of hypertension, diabetes and multimorbidity of chronic NCDs, but a lower prevalence of COPD than males (P < 0.05). Older adults with good household assets and access to medical services were less likely to experience multimorbidity, whereas obese and centrally obese participants, current smokers, current drinkers and those with a family history of chronic NCDs had a greater probability of multimorbidity. CONCLUSIONS: The findings suggest that effective strategies for prevention and control of chronic NCDs and its multimorbidity are urgently needed, especially for low-income, elderly, ethnic minority adults with poor access to medical services.


Assuntos
Doença das Coronárias/epidemiologia , Diabetes Mellitus/epidemiologia , Hipertensão/epidemiologia , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Doença Crônica/epidemiologia , Estudos Transversais , Feminino , Humanos , Estilo de Vida , Masculino , Multimorbidade , Doenças não Transmissíveis/epidemiologia , Obesidade/epidemiologia , Fatores de Risco , População Rural , Distribuição por Sexo , Fumar/epidemiologia , Fatores Socioeconômicos
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