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1.
Proc Natl Acad Sci U S A ; 120(17): e2302448120, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37068250

RESUMO

The tropane alkaloids (TAs) cocaine and hyoscyamine have been used medicinally for thousands of years. To understand the evolutionary origins and trajectories of serial biosynthetic enzymes of TAs and especially the characteristic tropane skeletons, we generated the chromosome-level genome assemblies of cocaine-producing Erythroxylum novogranatense (Erythroxylaceae, rosids clade) and hyoscyamine-producing Anisodus acutangulus (Solanaceae, asterids clade). Comparative genomic and phylogenetic analysis suggested that the lack of spermidine synthase/N-methyltransferase (EnSPMT1) in ancestral asterids species contributed to the divergence of polyamine (spermidine or putrescine) methylation in cocaine and hyoscyamine biosynthesis. Molecular docking analysis and key site mutation experiments suggested that ecgonone synthases CYP81AN15 and CYP82M3 adopt different active-site architectures to biosynthesize the same product ecgonone from the same substrate in Erythroxylaceae and Solanaceae. Further synteny analysis showed different evolutionary origins and trajectories of CYP81AN15 and CYP82M3, particularly the emergence of CYP81AN15 through the neofunctionalization of ancient tandem duplication genes. The combination of structural biology and comparative genomic analysis revealed that ecgonone methyltransferase, which is responsible for the biosynthesis of characteristic 2-substituted carboxymethyl group in cocaine, evolved from the tandem copies of salicylic acid methyltransferase by the mutations of critical E216 and S153 residues. Overall, we provided strong evidence for the independent origins of serial TA biosynthetic enzymes on the genomic and structural level, underlying the chemotypic convergence of TAs in phylogenetically distant species.


Assuntos
Cocaína , Hiosciamina , Solanaceae , Filogenia , Simulação de Acoplamento Molecular , Tropanos , Solanaceae/genética , Genômica , Metiltransferases/genética
2.
N Engl J Med ; 386(16): 1495-1504, 2022 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-35443107

RESUMO

BACKGROUND: The long-term efficacy and safety of time-restricted eating for weight loss are not clear. METHODS: We randomly assigned 139 patients with obesity to time-restricted eating (eating only between 8:00 a.m. and 4:00 p.m.) with calorie restriction or daily calorie restriction alone. For 12 months, all the participants were instructed to follow a calorie-restricted diet that consisted of 1500 to 1800 kcal per day for men and 1200 to 1500 kcal per day for women. The primary outcome was the difference between the two groups in the change from baseline in body weight; secondary outcomes included changes in waist circumference, body-mass index (BMI), amount of body fat, and measures of metabolic risk factors. RESULTS: Of the total 139 participants who underwent randomization, 118 (84.9%) completed the 12-month follow-up visit. The mean weight loss from baseline at 12 months was -8.0 kg (95% confidence interval [CI], -9.6 to -6.4) in the time-restriction group and -6.3 kg (95% CI, -7.8 to -4.7) in the daily-calorie-restriction group. Changes in weight were not significantly different in the two groups at the 12-month assessment (net difference, -1.8 kg; 95% CI, -4.0 to 0.4; P = 0.11). Results of analyses of waist circumferences, BMI, body fat, body lean mass, blood pressure, and metabolic risk factors were consistent with the results of the primary outcome. In addition, there were no substantial differences between the groups in the numbers of adverse events. CONCLUSIONS: Among patients with obesity, a regimen of time-restricted eating was not more beneficial with regard to reduction in body weight, body fat, or metabolic risk factors than daily calorie restriction. (Funded by the National Key Research and Development Project [No. 2018YFA0800404] and others; ClinicalTrials.gov number, NCT03745612.).


Assuntos
Restrição Calórica , Jejum , Obesidade , Redução de Peso , Composição Corporal , Índice de Massa Corporal , Restrição Calórica/métodos , Feminino , Humanos , Masculino , Obesidade/dietoterapia , Fatores de Tempo
3.
Neuroendocrinology ; 114(2): 170-178, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37725912

RESUMO

INTRODUCTION: The association of serum sex hormone-binding globulin (SHBG) concentrations with dementia risk remains uncertain in middle-aged to older women. We examined associations of serum SHBG levels with incidence of all-cause dementia and its subtypes in middle-aged to older women from the large population-based UK Biobank cohort study. METHODS: Serum total SHBG levels were measured by immunoassay. The incidence of all-cause dementia and its subtypes was recorded. Cox proportional hazards models were used to calculate hazard ratios (HR) for main outcomes. RESULTS: Among 171,482 community-dwelling women (mean [SD] age was 59.9 [5.4] years, median follow-up of 11.8 years), 2,368 developed dementia, including 1,088 from Alzheimer's disease (AD), 451 from vascular dementia (VAD), and 1,609 from other dementia. After multivariable adjustments, higher serum SHBG levels were significantly associated with higher risks of all-cause dementia, AD, and other dementia (all p < 0.05). Compared to those in the lowest quartile of SHBG levels, participants in the highest quartile of SHBG levels had a higher risk of all-cause dementia (HR: 1.34; 95% confidence interval [CI]: 1.16-1.53), AD (HR: 1.32; 95% CI: 1.07-1.62), and other dementia (HR: 1.44; 95% CI: 1.21-1.70). However, this relationship was not significant for VAD (HR: 1.16; 95% CI: 0.86-1.56). CONCLUSION: These findings indicated that higher serum SHBG concentrations were independently associated with higher risks of incident all-cause dementia, as well as AD and other dementia among middle-aged to older women. No association was found for VAD.


Assuntos
Doença de Alzheimer , Globulina de Ligação a Hormônio Sexual , Idoso , Pré-Escolar , Feminino , Humanos , Pessoa de Meia-Idade , Bancos de Espécimes Biológicos , Estudos de Coortes , Estudos Prospectivos , Fatores de Risco , Biobanco do Reino Unido
4.
J Integr Plant Biol ; 66(6): 1158-1169, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38517054

RESUMO

Camptothecin is a complex monoterpenoid indole alkaloid with remarkable antitumor activity. Given that two C-10 modified camptothecin derivatives, topotecan and irinotecan, have been approved as potent anticancer agents, there is a critical need for methods to access other aromatic ring-functionalized congeners (e.g., C-9, C-10, etc.). However, contemporary methods for chemical oxidation are generally harsh and low-yielding when applied to the camptothecin scaffold, thereby limiting the development of modified derivatives. Reported herein, we have identified four tailoring enzymes responsible for C-9 modifications of camptothecin from Nothapodytes tomentosa, via metabolomic and transcriptomic analysis. These consist of a cytochrome P450 (NtCPT9H) which catalyzes the regioselective oxidation of camptothecin to 9-hydroxycamptothecin, as well as two methyltransferases (NtOMT1/2, converting 9-hydroxycamptothecin to 9-methoxycamptothecin), and a uridine diphosphate-glycosyltransferase (NtUGT5, decorating 9-hydroxycamptothecin to 9-ß-D-glucosyloxycamptothecin). Importantly, the critical residues that contribute to the specific catalytic activity of NtCPT9H have been elucidated through molecular docking and mutagenesis experiments. This work provides a genetic basis for producing camptothecin derivatives through metabolic engineering. This will hasten the discovery of novel C-9 modified camptothecin derivatives, with profound implications for pharmaceutical manufacture.


Assuntos
Camptotecina , Camptotecina/farmacologia , Sistema Enzimático do Citocromo P-450/metabolismo
5.
J Am Chem Soc ; 145(51): 28010-28021, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38095915

RESUMO

Phase regulation of noble metal-based nanomaterials provides a promising strategy for boosting the catalytic performance. However, realizing the continuous phase modulation in two-dimensional structures and unveiling the relevant structure-performance relationship remain significant challenges. In this work, we present the first example of continuous phase modulation in a library of Pd-Te hexagonal nanoplates (HNPs) from cubic-phase Pd4Te, rhombohedral-phase Pd20Te7, rhombohedral-phase Pd8Te3, and hexagonal-phase PdTe to hexagonal-phase PdTe2. Notably, the continuous phase regulation of the well-defined Pd-Te HNPs enables the successful modulation of the distance between adjacent Pd active sites, triggering an exciting way for tuning the relevant catalytic reactions intrinsically. The proof-of-concept oxygen reduction reaction (ORR) experiment shows a Pd-Pd distance-dependent ORR performance, where the hexagonal-phase PdTe HNPs present the best electrochemical performance in ORR (mass activity and specific activity of 1.02 A mg-1Pd and 1.83 mA cm-2Pd at 0.9 V vs RHE). Theoretical investigation reveals that the increased Pd-Pd distance relates to the weak *OH adsorption over Pd-Te HNPs, thus contributing to the remarkable ORR activity of PdTe HNPs. This work advances the phase-controlled synthesis of noble metal-based nanostructures, which gives huge impetus to the design of high-efficiency nanomaterials for diverse applications.

6.
Nanotechnology ; 34(18)2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36716479

RESUMO

Lanthanide (Ln) rare Earth (RE) elements are often used to incorporate and regulate the local coordination environment and electronic configuration of transition metal based electrocatalysts for acquiring improved electrocatalytic performance. But for a given pristine electrode, is a Ln element concentrated more on promoting the apparent activity of original electrode or on enhancing its specific activity? To address this issue, Ln (La, Ce and Nd) decorated ZIF-67 derivative electrodes (Ln/Co/NC) were fabricated following with the detailed experimental testing of apparent activity and specific activity of assembled electrodes. X-ray photoelectron spectroscopy data confirmed that Ce, Nd and La have played their own role in regulating the coordination electronic structure of the surface atoms of the derived Co/NC by forming different types of chemical bonds. Electrochemical (EC) results confirmed that Ce is concentrated more on the apparent activity of derived Co/NC electrode with the smallest overpotential at 50 mA cm-2(η50), while Nd contributes more to its reaction kinetic property with the smallest value of Tafel slope in alkaline hydrogen evolution reaction process. But for oxygen evolution reaction, all of La, Ce and Nd deteriorate the apparent activity of the pristine Co/NC electrode. Comparatively, La shows a greater ability to modulate the specific activity of Co/NC with a larger electrochemical active surface area normalized current density, while Nd exhibits the best ability to re-establish the properties of reaction centers. This work illustrates the difference influence of La, Ce and Nd on the apparent activity and specific activity of the ZIF-67 derivative Co/NC electrode. It will do some favors in engineering RE elements modified composite electrodes for EC applications.

7.
Small ; 16(2): e1904252, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31821688

RESUMO

Increasing active sites is an effective method to enhance the catalytic activity of catalysts. Amorphous materials have attracted considerable attention in catalysis because of their abundant catalytic active sites. Herein, a series of derivatives is prepared via the low-temperature heat treatment of ZIF-67 hollow sphere at different temperatures. An intermediate product with an amorphous structure is formed during transformation from ZIF-67 to Co3 O4 nanocrystallines when ZIF-67 hollow sphere is heat treated at 260 °C for 3 h. The chemical composition of the amorphous derivative is similar to that of ZIF-67, and the carbon and nitrogen contents of the amorphous derivative are obviously higher than those of crystalline samples obtained at 270 °C or higher. As electrocatalysts for the oxygen evolution reaction (OER) and nonenzymatic glucose sensing, the amorphous derivative exhibits significantly better catalytic activity than crystalline Co3 O4 samples. The amorphous sample as an OER catalyst has a low overpotential of 352 mV at 10 mA cm-2 . The amorphous sample as an enzyme-free glucose sensing catalyst can provide a low detection limit of 3.9 × 10-6 m and a high sensitivity of 1074.22 µA mM-1 cm-2 .

8.
Nanotechnology ; 30(20): 204002, 2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-30669138

RESUMO

As highly efficient and clean electrochemical energy storage devices, supercapacitors (SCs) have drawn widespread attention as promising alternatives to batteries in recent years. Among various electrode materials, iron oxide materials have been widely studied as negative SC electrode materials due to their broad working window in negative potential, ideal theoretical specific capacitance, good redox activity, abundant availability, and eco-friendliness. However, iron oxides still suffer from the problems of low stability and poor conductivity. In this review, recent progress in iron oxide-based nanomaterials, including Fe2O3, Fe3O4, FexOy, and FeOOH, as electrode materials of SCs, is discussed. The nanostructure design and various synergistic effects of nanocomposites for improving the electrochemical performance of iron oxides are emphasized. Research on iron oxide-based symmetric/asymmetric SCs is also discussed. Future outlooks regarding iron oxides for SCs are likewise proposed.

9.
Zhongguo Zhong Yao Za Zhi ; 43(6): 1221-1227, 2018 Mar.
Artigo em Zh | MEDLINE | ID: mdl-29676132

RESUMO

To study the effect of aqueous extracts of Yiqi Jiedu formula (YQ) on the proliferation of CNE2 cells in human nasopharyngeal carcinoma, and investigate its mechanism to provide a new theoretical basis for the clinical application of YQ. CNE2 cells were treated with different concentrations (0.125, 0.25, 0.5, 0.25 g·L⁻¹) of YQ, positive control medicine (cisplatin 4.0 mg·L⁻¹), inhibitor PD98059 (50 µmol·L⁻¹), activator isoproterenol hydrochloride (20 µmol·L⁻¹), activator isoproterenol hydrochloride (ISO)+YQ 0.5 g·L⁻¹. Then cell labeling by using real-time analyzer (RTCA) and CCK 8 method were used to detect cell proliferation activity, and the half inhibitory concentration (IC50) was calculated. The cell cycle distribution was detected by fluorescence double dye flow cytometry PI staining, and Western blot method was used to detect the expression levels of related protein and MAPK/ERK signaling pathway. The results of RTCA and CCK-8 test showed that as compared with the control group, YQ group could effectively inhibit the proliferation of CNE2 cells (P<0.01), with a dose and time dependence, and 48 h IC50 value was 0.5 g·L⁻¹. The results of cell cycle showed that after 48 h of water extract treatment, the cell cycle was significantly changed, the proportion of G0/G1 was reduced, the ratio of G2/M increased, and the cell cycle was in G2/M period (P<0.01). Western blot results showed that after 48 h treatment with different concentrations of aqueous extract, cell cycle-related proteins cyclinD1, cyclinD3 and CDK2 expression levels were down-regulated; MAPK/ERK signaling pathway related protein p-c-Raf, p-MEK, p-ERK1/2 expression level significantly lower as compared with the control group (P<0.05). After adding activator and inhibitor in MAPK/ERK signaling pathway on this basis, the results showed that after adding activator ISO, cell proliferation was significantly higher than that in the Control group; the cycle related proteins cyclinD1, cyclinD3, and CDK2 expression levels were increased; at the same time, key protein p-c-Raf, p-MEK, p-ERK1/2 expression levels in the signal pathways were relatively increased. While after the addition of inhibitor PD98059, the cell proliferation was significantly lower than that in the Control group, and the expression level of corresponding protein was decreased, which was significantly different from the Control group (P<0.05). So YQ could block cell cycle and inhibit the proliferation of CNE2 cells mainly by reducing the expression of MAPK/ERK signaling pathway key protein p-c-Raf, p-MEK and p-ERK1/2.


Assuntos
Proliferação de Células/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Carcinoma Nasofaríngeo/patologia , Linhagem Celular Tumoral , Humanos
10.
J Clin Endocrinol Metab ; 109(2): e745-e756, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-37665960

RESUMO

CONTEXT: Sex hormones have been identified as cardiovascular risk factors, whereas the relationship between sex hormones and the risk of arrhythmias in men has not yet been well studied in the prospective cohort study. OBJECTIVE: To analyze associations of serum testosterone and SHBG concentrations and calculate free testosterone (cFT) with arrhythmias in men. METHODS: Sex hormones were measured at baseline from UK Biobank. Main outcomes were incidence of atrial fibrillation/flutter (AF), ventricular arrhythmia (VA), and bradyarrhythmia (BA). RESULTS: Of 173 498 men (aged 37-73 years, followed for 11 years), 11 368 had incident AF, 1646 had incident VA, and 4788 had incident BA. Compared with the third quartiles, the lowest category of serum testosterone was associated with increased risks of AF (hazard ratio [HR], 1.06; 95% CI, 1.00-1.12) and BA (HR, 1.11; 95% CI, 1.02-1.20) after multivariable adjustment, but no VA. Likewise, similar associations were found between cFT values and AF and BA events. Furthermore, higher levels of cFT were associated with increased risks of AF (HR, 1.07; 95% CI, 1.02-1.13) and VA (HR, 1.18; 95% CI, 1.01-1.37). Higher SHBG concentrations were associated with increased risks of AF (HR, 1.44; 95% CI, 1.34-1.54), VA (HR, 1.27; 95% CI, 1.07-1.52), and BA (HR, 1.17; 95% CI ,1.05-1.29). CONCLUSIONS: Lower levels of testosterone and cFT were associated with increased risk of AF and BA. Higher cFT levels were associated with increased risk of AF and VA. Higher SHBG levels were associated with increased risk of AF, VA, and BA.


Assuntos
Fibrilação Atrial , Globulina de Ligação a Hormônio Sexual , Masculino , Humanos , Estudos Prospectivos , Biobanco do Reino Unido , Bancos de Espécimes Biológicos , Testosterona , Hormônios Esteroides Gonadais , Fibrilação Atrial/epidemiologia
11.
Nat Nanotechnol ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38918614

RESUMO

Constructing regioselective architectures in heterostructures is important for many applications; however, the targeted design of regioselective architectures is challenging due to the sophisticated processes, impurity pollution and an unclear growth mechanism. Here we successfully realized a one-pot kinetically controlled synthetic framework for constructing regioselective architectures in metallic heterostructures. The key objective was to simultaneously consider the reduction rates of metal precursors and the lattice matching relationship at heterogeneous interfaces. More importantly, this synthetic method also provided phase- and morphology-independent behaviours as foundations for choosing substrate materials, including phase regulation from Pd20Sb7 hexagonal nanoplates (HPs) to Pd8Sb3 HPs, and morphology regulation from Pd20Sb7 HPs to Pd20Sb7 rhombohedra and Pd20Sb7 nanoparticles. Consequently, the activity of regioselective epitaxially grown Pt on Pd20Sb7 HPs was greatly enhanced towards the ethanol oxidation reaction; its activity was 57 times greater than that of commercial Pt/C, and the catalyst showed increased stability (decreasing by 16.3% after 2,000 cycles) and selectivity (72.4%) compared with those of commercial Pt/C (56.0%, 18.2%). This work paves the way for the design of unconventional well-defined heterostructures for use in various applications.

12.
Anal Chim Acta ; 1274: 341580, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37455088

RESUMO

Traditional immunoassay methods often face challenges due to the labeling procedure of protein enzymes, the use of multiple antibodies, and severe conditions. To address these limitations, we propose the concept of incorporating branchedzyme-powered nanodevices into immunoassays. In this strategy, multiple DNAzymes are localized onto gold nanoparticles (AuNPs) along with substrates. The localization format facilitates intramolecular reactions between DNAzymes and substrates, leading to accelerated kinetics of the nanodevice. Upon the formation of an immunocomplex with an antibody on a 96-well plate, the branchedzyme-powered nanodevice catalytically releases multiple fluorescent signals under ambient temperature, eliminating the need for secondary antibodies. The branched DNAzymes exhibit catalytic properties similar to those of protein enzymes, thus simplifying the assay procedure and achieving isothermal detection. Furthermore, the detection process can be controlled by the addition or deletion of cofactors. Additionally, the affinity ligand can be easily modified to construct nanodevices specific to different targets without requiring extensive redesign. This strategy has demonstrated successful quantification of tumor biomarkers such as alpha-fetoprotein (AFP) and prostate-specific antigen (PSA) at subpicomolar concentrations, showcasing its suitability for clinical applications. Consequently, the branchedzyme-powered nanodevice represents a valuable addition to the immunoassay toolbox, opening new possibilities for clinical diagnostics.


Assuntos
Técnicas Biossensoriais , DNA Catalítico , Nanopartículas Metálicas , Humanos , Masculino , Biomarcadores Tumorais , DNA Catalítico/química , Ouro/química , Nanopartículas Metálicas/química , Imunoensaio/métodos , Anticorpos
13.
Nanomaterials (Basel) ; 13(4)2023 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-36838992

RESUMO

A novel engineered carbon cloth (CC)-based self-cleaning membrane containing a Cu:TiO2 and Ag coating has been created via hydrothermal and light deposition methods. The engineered membrane with chrysanthemum morphology has superhydrophilic and underwater superoleophilic performance. The cooperativity strategy of Cu doping and Ag coating to the TiO2 is found to be critical for engineering the separation efficiency and self-cleaning skill of the CC-based membrane under visible light due to the modulated bandgap structure and surface plasmon resonance. The CC-based membrane has excellent oil-water separation performance when Cu is fixed at 2.5 wt% and the Ag coating reaches a certain amount of 0.003 mol/L AgNO3. The contact angle of underwater oil and the separation efficiency are 156° and 99.76%, respectively. Furthermore, the membrane has such an outstanding self-cleaning ability that the above performance can be nearly completely restored after 30 min of visible light irradiation, and the separation efficiency can still reach 99.65% after 100 cycles. Notably, the membrane with exceptional wear resistance and durability can work in various oil-water mixtures and harsh environments, indicating its potential as a new platform of the industrial-level available membrane in dealing with oily wastewater.

14.
Environ Sci Pollut Res Int ; 30(44): 99412-99426, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37612561

RESUMO

The construction of novel efficient catalysts for the treatment of organic pollutants in the aqueous environment is essential. The lamellar-like Cu-Al layered double hydroxides (CuAl-LDHs) with various mole ratios were synthesized by a simple route of co-precipitation, and the corresponding degradation characteristic was tested for the removal of tetracycline (TC) using PMS activation. The degradation efficiency of TC over CuAl-LDHs increased up to 93% within 10 min for the Cu/Al mole ratio of 3:1 and almost not changed at a higher mole ratio. For further calcining the optimal catalyst at 300 ℃, the degradation efficiency of TC was found to be increased to 96%. Sulfuric radicals and singlet oxygen were analyzed to be the main reason for the change in degradation characteristics, which was proved by radical quenching experiments and electron paramagnetic resonance technique. The parameters including PMS concentration, catalyst dosage, and reaction temperature on the TC degradation as well as the degradation mechanism for PMS activation were elaborated. The best proportion of CuAl-LDHs owned splendid stability and catalytic activity after reusing, which showed enormous potential in practical application.


Assuntos
Hidróxidos , Tetraciclina , Antibacterianos , Água , Catálise , Peróxidos
15.
J Clin Endocrinol Metab ; 108(9): e850-e860, 2023 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-36810801

RESUMO

CONTEXT: Relationships between insulin-like growth factor 1 (IGF-1) levels and cardiovascular disease (CVD) in the general population remain unclear. OBJECTIVE: This study aims to investigate the association of circulating IGF-1 concentrations with CVD from a population-based cohort study. METHODS: A total of 394 082 participants without CVD and cancer at baseline from UK Biobank were included with measurements of serum IGF-1 at baseline. Main outcomes were incidence of CVD, including CVD mortality, coronary heart disease (CHD), myocardial infarction (MI), heart failure (HF), and stroke. RESULTS: Over a median 11.6 years of follow-up, UK Biobank documented 35 803 incident CVD cases, including 4231 from CVD-related death, 27 051 from CHD, 10 014 from MI, 7661 from HF, and 6802 from stroke. Dose-response analysis showed a U-shaped relationship between IGF-1 levels and cardiovascular events. Compared with the third quintile of IGF-1, the lowest category of IGF-1 was associated with increased risk of CVD (hazard ratio 1.128; 95% CI, 1.093 to 1.164), CVD mortality (1.294; 1.181 to 1.418), CHD (1.118; 1.078 to 1.159), MI (1.071; 1.008 to 1.139), HF (1.185; 1.107 to 1.268), and stroke (1.149, 1.070 to 1.235); also, the highest category was associated with increased risk of CVD (1.056; 1.020 to 1.094), CVD mortality (1.111; 1.000 to 1.236), CHD (1.070; 1.028 to 1.114), MI (1.111; 1.041 to 1.187) and HF (1.098; 1.015 to 1.188) after multivariable adjustment. CONCLUSION: This study indicates that both low and high levels of circulating IGF-1 are associated with increased risk of CVD in general population. These results highlight the importance of monitoring IGF-1 status on cardiovascular health.


Assuntos
Doenças Cardiovasculares , Doença das Coronárias , Insuficiência Cardíaca , Infarto do Miocárdio , Acidente Vascular Cerebral , Humanos , Doenças Cardiovasculares/etiologia , Estudos de Coortes , Fator de Crescimento Insulin-Like I/metabolismo , Bancos de Espécimes Biológicos , Fatores de Risco , Infarto do Miocárdio/complicações , Insuficiência Cardíaca/epidemiologia , Doença das Coronárias/epidemiologia , Acidente Vascular Cerebral/complicações , Reino Unido/epidemiologia
16.
J Am Heart Assoc ; 12(16): e030105, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37581386

RESUMO

Background The associations of oral contraceptive (OC) use with cardiovascular disease (CVD) and all-cause death remains unclear. We aimed to determine the associations of OC use with incident CVD and all-cause death. Methods and Results This cohort study included 161 017 women who had no CVD at baseline and reported their OC use. We divided OC use into ever use and never use. Cox proportional hazard models were used to calculate hazard ratios and 95% CIs for cardiovascular outcomes and death. Overall, 131 131 (81.4%) of 161 017 participants reported OC use at baseline. The multivariable-adjusted hazard ratios for OC ever users versus never users were 0.92 (95% CI, 0.86-0.99) for all-cause death, 0.91 (95% CI, 0.87-0.96) for incident CVD events, 0.88 (95% CI, 0.81-0.95) for coronary heart disease, 0.87 (95% CI, 0.76-0.99) for heart failure, and 0.92 (95% CI, 0.84-0.99) for atrial fibrillation. However, no significant associations of OC use with CVD death, myocardial infarction, or stroke were observed. Furthermore, the associations of OC use with CVD events were stronger among participants with longer durations of use (P for trend<0.001). Conclusions OC use was not associated with an increased risk of CVD events and all-cause death in women and may even produce an apparent net benefit. In addition, the beneficial effects appeared to be more apparent in participants with longer durations of use.


Assuntos
Doenças Cardiovasculares , Humanos , Feminino , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/induzido quimicamente , Estudos de Coortes , Fatores de Risco , Bancos de Espécimes Biológicos , Anticoncepcionais Orais/efeitos adversos , Reino Unido/epidemiologia
17.
JAMA Netw Open ; 6(3): e233513, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36930148

RESUMO

Importance: The efficacy and safety of time-restricted eating (TRE) on nonalcoholic fatty liver disease (NAFLD) remain uncertain. Objective: To compare the effects of TRE vs daily calorie restriction (DCR) on intrahepatic triglyceride (IHTG) content and metabolic risk factors among patients with obesity and NAFLD. Design, Setting, and Participants: This 12-month randomized clinical trial including participants with obesity and NAFLD was conducted at the Nanfang Hospital in Guangzhou, China, between April 9, 2019, and August 28, 2021. Interventions: Participants with obesity and NAFLD were randomly assigned to TRE (eating only between 8:00 am and 4:00 pm) or DCR (habitual meal timing). All participants were instructed to maintain a diet of 1500 to 1800 kcal/d for men and 1200 to 1500 kcal/d for women for 12 months. Main Outcomes and Measures: The primary outcome was change in IHTG content measured by magnetic resonance imaging; secondary outcomes were changes in body weight, waist circumference, body fat, and metabolic risk factors. Intention-to-treat analysis was used. Results: A total of 88 eligible patients with obesity and NAFLD (mean [SD] age, 32.0 [9.5] years; 49 men [56%]; and mean [SD] body mass index, 32.2 [3.3]) were randomly assigned to the TRE (n = 45) or DCR (n = 43) group. The IHTG content was reduced by 8.3% (95% CI, -10.0% to -6.6%) in the TRE group and 8.1% (95% CI, -9.8% to -6.4%) in the DCR group at the 6-month assessment. The IHTG content was reduced by 6.9% (95% CI, -8.8% to -5.1%) in the TRE group and 7.9% (95% CI, -9.7% to -6.2%) in the DCR group at the 12-month assessment. Changes in IHTG content were comparable between the 2 groups at 6 months (percentage point difference: -0.2; 95% CI, -2.7 to 2.2; P = .86) and 12 months (percentage point difference: 1.0; 95% CI, -1.6 to 3.5; P = .45). In addition, liver stiffness, body weight, and metabolic risk factors were significantly and comparably reduced in both groups. Conclusions and Relevance: Among adults with obesity and NAFLD, TRE did not produce additional benefits for reducing IHTG content, body fat, and metabolic risk factors compared with DCR. These findings support the importance of caloric intake restriction when adhering to a regimen of TRE for the management of NAFLD. Trial Registration: ClinicalTrials.gov Identifiers: NCT03786523 and NCT04988230.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Adulto , Masculino , Humanos , Feminino , Hepatopatia Gordurosa não Alcoólica/complicações , Obesidade/complicações , Obesidade/metabolismo , Fatores de Risco , Triglicerídeos/metabolismo , Tecido Adiposo
18.
J Am Heart Assoc ; 12(11): e029020, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37222132

RESUMO

Background The association between menstrual cycle characteristics and cardiovascular outcomes remains unclear. This study was undertaken to evaluate whether menstrual cycle regularity and length throughout the life course are associated with cardiovascular outcomes. Methods and Results This cohort study included 58 056 women who had no cardiovascular disease (CVD) at baseline and reported their menstrual cycle regularity and length. Hazard ratios (HRs) and 95% CIs for CVD events were estimated using Cox proportional hazards models. During the median 11.8 years of follow-up, 1623 incident CVD cases were documented, including 827 incident cases of coronary heart disease, 199 myocardial infarctions, 271 strokes, 174 cases of heart failure, and 393 cases of atrial fibrillations. Compared with women with regular menstrual cycles, the HRs for women with irregular menstrual cycles were 1.19 (95% CI, 1.07-1.31) for CVD events and 1.40 (95% CI, 1.14-1.72) for atrial fibrillation. The multivariable-adjusted HRs for short (≤21 days) or long (35 days) menstrual cycles during follow-up were 1.29 (95% CI, 1.11-1.50) and 1.11 (95% CI, 0.98-1.56) for CVD events, respectively. Similarly, long or short cycle length were more likely to be associated with increased risk of atrial fibrillation (HR, 1.30 [95% CI, 1.01-1.66]; and HR, 1.38 [95% CI, 1.02-1.87]), and short cycle length was more likely to be associated with increased risk of coronary heart disease and myocardial infarction. However, these associations for stroke and heart failure were not significant. Conclusions Long or short menstrual cycle length was associated with increased risks of CVD and atrial fibrillation but not myocardial infarction, heart failure, or stroke. Short cycle length was associated with a greater risk of coronary heart disease and myocardial infarction.


Assuntos
Fibrilação Atrial , Doenças Cardiovasculares , Doença das Coronárias , Insuficiência Cardíaca , Infarto do Miocárdio , Acidente Vascular Cerebral , Humanos , Feminino , Estudos Prospectivos , Estudos de Coortes , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/complicações , Bancos de Espécimes Biológicos , Fatores de Risco , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/complicações , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/complicações , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/complicações , Doença das Coronárias/epidemiologia , Doença das Coronárias/complicações , Acidente Vascular Cerebral/etiologia , Ciclo Menstrual , Reino Unido/epidemiologia
19.
Adv Mater ; 34(31): e2202333, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35676861

RESUMO

Developing high-performance electrocatalysts for the ethanol oxidation reaction (EOR) and the oxygen reduction reaction (ORR) is essential for the commercialization of direct ethanol fuel cells, but it is still formidably challenging. In this work, a novel Pd-Sb hexagonal nanoplate for boosting both cathodic and anodic fuel cell reactions is prepared. Detailed characterizations reveal that the nanoplates have ordered rhombohedral phase of Pd8 Sb3 (denoted as Pd8 Sb3 HPs). The Pd8 Sb3 HPs exhibit much enhanced activity toward the oxidation of various alcohols. Particularly, Pd8 Sb3 HPs/C displays superior specific and mass activities of 29.3 mA cm-2 and 4.5 A mgPd -1 toward the EOR, which are 7.0 and 11.3 times higher than those of commercial Pd/C, and 9.8 and 3.8 times higher than those of commercial Pt/C, respectively, representing one of the best EOR catalysts reported to date. In situ electrochemical attenuated total reflectance surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) measurements reveal that Pd8 Sb3 HPs/C can effectively promote the C2 pathway of the EOR. As revealed by density functional theory calculations, the high EOR activity of the Pd8 Sb3 HPs can be ascribed to the reduced energy barrier of ethanol dehydrogenation. Additionally, Pd8 Sb3 HPs/C also shows superior performance in the ORR. This work advances the controllable synthesis of the Pd-Sb nanostructure, giving huge impetus for the design of high-efficiency electrocatalysts for energy conversion and beyond.

20.
Nat Commun ; 13(1): 4994, 2022 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-36008484

RESUMO

Tropane alkaloids such as hyoscyamine and cocaine are of importance in medicinal uses. Only recently has the hyoscyamine biosynthetic machinery become complete. However, the cocaine biosynthesis pathway remains only partially elucidated. Here we characterize polyketide synthases required for generating 3-oxo-glutaric acid from malonyl-CoA in cocaine biosynthetic route. Structural analysis shows that these two polyketide synthases adopt distinctly different active site architecture to catalyze the same reaction as pyrrolidine ketide synthase in hyoscyamine biosynthesis, revealing an unusual parallel/convergent evolution of biochemical function in homologous enzymes. Further phylogenetic analysis suggests lineage-specific acquisition of polyketide synthases required for tropane alkaloid biosynthesis in Erythroxylaceae and Solanaceae species, respectively. Overall, our work elucidates not only a key unknown step in cocaine biosynthesis pathway but also, more importantly, structural and biochemical basis for independent recruitment of polyketide synthases in tropane alkaloid biosynthesis, thus broadening the understanding of conservation and innovation of biosynthetic catalysts.


Assuntos
Cocaína , Hiosciamina , Filogenia , Policetídeo Sintases/metabolismo , Tropanos/metabolismo
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