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1.
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
2.
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
3.
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.

4.
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
5.
Front Neurosci ; 16: 910977, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36161159

RESUMO

Background: Although numerous studies have investigated the association of dietary intake of omega-3 fatty acids with cognitive function and the risks of dementia, the relationship between fish oil supplementation and incident dementia in a large population-based cohort study has not yet well studied. Materials and methods: A total of 211,094 community-dwelling older persons over 60 years from the UK Biobank cohorts enrolled between 2006 and 2010 that reported regularly taking fish oil and had no dementia at baseline, was included in the present study. All participants completed an electronic questionnaire regarding habitual use of supplements including fish oil. Results: Overall, 83,283 (39.5%) participants reported regularly taking fish oil at baseline. Of 211,094 participants with the median age was 64.1 years, 5,274 participants developed dementia events during a median follow-up of 11.7 years, with 3,290 individuals derived from fish oil non-users. In the multivariable adjusted models, the adjusted hazard ratios (HRs) associated with fish oil supplementation for all-cause dementia, vascular dementia, frontotemporal dementia, and other dementia were 0.91 [CI = 0.84-0.97], 0.83 [CI = 0.71-0.97], 0.43 [CI = 0.26-0.72], 0.90 [CI = 0.82-0.98], respectively (all P < 0.05). However, no significant association between fish oil supplementation and Alzheimer's disease was found (HR = 1.00 [CI = 0.89-1.12], P = 0.977). In the subgroup analyses, the associations between use of fish oil and the risk of all-cause dementia (P for interaction = 0.007) and vascular dementia were stronger among men (P for interaction = 0.026). Conclusion: Among older adults, regular fish oil supplementation was significantly associated with a lower risks of incident all-cause dementia, as well as vascular dementia, frontotemporal dementia and other dementia but not Alzheimer's disease. These findings support that habitual use of fish oils may be beneficial for the prevention of dementia in clinical practice.

6.
Diabetes Care ; 45(5): 1219-1229, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35226734

RESUMO

OBJECTIVE: To examine the associations of circulating 25-hydroxyvitamin D (25[OH]D) concentrations with cardiovascular disease (CVD) and all-cause mortality in individuals with prediabetes and diabetes from the large population-based UK Biobank cohort study. RESEARCH DESIGN AND METHODS: A total of 67,789 individuals diagnosed with prediabetes and 24,311 with diabetes who had no CVD or cancer at baseline were included in the current study. Serum 25(OH)D concentrations were measured at baseline. Cox proportional hazard models were used to calculate hazard ratios (HRs) and 95% CIs for cardiovascular outcomes and mortality after 10-14 years. RESULTS: After multivariable adjustment, higher serum 25(OH)D levels were significantly and nonlinearly associated with lower risk of cardiovascular outcomes and all-cause mortality among participants with prediabetes and diabetes (all P nonlinearity < 0.05). Compared with those in the lowest category of 25(OH)D levels (<25 nmol/L), participants with prediabetes in the highest category of 25(OH)D levels (≥75 nmol/L) had a significant association with lower risk of cardiovascular events (HR 0.78; 95% CI 0.71-0.86), coronary heart disease (CHD) (HR 0.79; 95% CI 0.71-0.89), heart failure (HR 0.66; 95% CI 0.54-0.81), stroke (HR 0.75; 95% CI 0.61-0.93), CVD mortality (HR 0.43; 95% CI 0.32-0.59), and all-cause mortality (HR 0.66; 95% CI 0.58-0.75). Likewise, these associations with cardiovascular events, CHD, heart failure, CVD mortality, and all-cause mortality were observed among participants with diabetes, except for stroke. CONCLUSIONS: These findings highlight the importance of monitoring and correcting vitamin D deficiency in the prevention of CVD and mortality among adults with prediabetes and diabetes.


Assuntos
Doenças Cardiovasculares , Doença das Coronárias , Diabetes Mellitus , Insuficiência Cardíaca , Estado Pré-Diabético , Acidente Vascular Cerebral , Adulto , Bancos de Espécimes Biológicos , Estudos de Coortes , Humanos , Estudos Prospectivos , Fatores de Risco , Reino Unido/epidemiologia , Vitamina D/análogos & derivados
7.
Front Endocrinol (Lausanne) ; 11: 580097, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33117292

RESUMO

Background: Tsukushi (TSK) is a secreted hepatokine recently identified as playing an important role in modulating glucose and lipid metabolism, and systemic energy homeostasis. However, information is not available regarding the association between circulating TSK and hyperthyroidism in humans. Methods: We measured serum TSK levels in 180 patients with hyperthyroidism and 82 healthy controls recruited from the clinic. Of them, 46 hyperthyroid patients received thionamide treatment for 3 months. Results: Hyperthyroid patients had higher levels of circulating TSK than healthy controls [186.67 (133.63-280.59) ng/ml vs. 97.27 (77.87-146.96) ng/ml, P < 0.001]. Subjects with higher level of serum free triiodothyronine (T3) and free thyroxine (T4) had higher levels of circulating TSK. In addition, serum TSK levels markedly declined with the improvement of thyroid function after thionamide treatment. In multivariable linear regression analyses, circulating TSK concentrations were significantly associated with serum free T3, free T4, thyroid stimulating hormone, thyrotropin receptor antibody, total cholesterol, low-density lipoprotein cholesterol (LDL-cholesterol), high-density lipoprotein cholesterol (HDL-cholesterol), and basal metabolic rate (all P < 0.01), adjusting for age, gender, smoking, and body mass index (BMI). Importantly, circulating TSK was significantly associated with risks of hyperthyroidism in multivariable logistic regression analyses, adjusting for age, gender, smoking, BMI, fasting glucose, LDL-cholesterol, and insulin resistance (HOMA-IR) [OR (95% CI), 1.012(1.005-1.019), P = 0.001]. Conclusion: These findings indicate that circulating TSK concentrations are independently associated with hyperthyroidism, suggesting that circulating TSK may be a predictive factor of hyperthyroidism and can be used for therapeutic monitoring.


Assuntos
Biomarcadores/sangue , Colesterol/sangue , Hipertireoidismo/diagnóstico , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Proteoglicanas/sangue , Hormônios Tireóideos/sangue , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Hipertireoidismo/sangue , Masculino , Testes de Função Tireóidea
8.
Endocr Connect ; 9(8): 783-792, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32688342

RESUMO

BACKGROUND: Glycoprotein non-metastatic protein B (Gpnmb) has been identified as a new cytokine secreted by hepatocyte that plays an important role in balancing lipid homeostasis and development of obesity and metabolic disorders. However, information is not available regarding the association between circulating Gpnmb and hyperthyroid in humans. METHODS: We measured serum Gpnmb in 180 hyperthyroid patients and 82 healthy subjects that were recruited from the clinic. Of them, 46 hyperthyroid patients received thionamide treatment for 3 months. RESULTS: Hyperthyroid subjects had higher levels of circulating Gpnmb than healthy controls (47.8 ± 10.1 ng/mL vs 31.0 ± 4.9 ng/mL, P < 0.001). Subjects with higher levels of serum free triiodothyronine (T3) and free thyroxine (T4) had higher levels of circulating Gpnmb. After thionamide treatment, levels of circulating Gpnmb in hyperthyroid subjects remarkably declined with significant improvement of thyroid function (P < 0.001). Furthermore, the change of circulating Gpnmb levels was significantly associated with basal metabolic rate (BMR) and thyroid hormones, including free T3 and free T4, adjusting for age, gender, smoking and BMI before thionamide treatment. In multivariable logistic regression analyses, circulating Gpnmb was significantly associated with risks of hyperthyroidism (OR (95% CI): 1.44 (1.20-1.74), P < 0.001), adjusted for age, gender, BMI, fasting glucose, HOMA-IR, LDL-cholesterol, ALT and AST. CONCLUSIONS: These findings indicate that circulating Gpnmb concentrations are independently associated with hyperthyroid, suggesting that circulating Gpnmb may be a predictor of risk for hyperthyroidism and can be used for therapeutic monitoring.

9.
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.

10.
Zhongguo Zhong Yao Za Zhi ; 43(6): 1221-1227, 2018 Mar.
Artigo em Chinês | 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
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