Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 30
Filtrar
1.
Kidney Blood Press Res ; 48(1): 277-286, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36996765

RESUMO

INTRODUCTION: Renal function has an important bearing on plasma homocysteine levels. Plasma homocysteine is related to left ventricular hypertrophy (LVH). However, it remains unclear whether the association between plasma homocysteine levels and LVH is influenced by renal function. This study aimed to investigate relationships among left ventricular mass index (LVMI), plasma homocysteine levels, and renal function in a population from southern China. METHODS: A cross-sectional study was performed in 2,464 patients from June 2016 to July 2021. Patients were divided into three groups based on gender-specific tertiles of homocysteine levels. LVMI ≥115 g/m2 for man or ≥95 g/m2 for woman was defined as LVH. RESULTS: LVMI and the percentage of LVH were increased, while estimated glomerular filtration rate (eGFR) was decreased with the increase in homocysteine levels, both significantly. Multivariate stepwise regression analysis showed that eGFR and homocysteine were independently associated with LVMI in patients with hypertension. No correlation was observed between homocysteine and LVMI in patients without hypertension. Stratified by eGFR, further analysis confirmed homocysteine was independently associated with LVMI (ß = 0.126, t = 4.333, p < 0.001) only in hypertensive patients with eGFR ≥90 mL/(min·1.73 m2), not with 60≤ eGFR <90 mL/(min·1.73 m2). Multivariate logistic regression indicated that in hypertensive patients with eGFR ≥90 mL/(min·1.73 m2), the patients in high tertile of homocysteine levels had a nearly twofold increased risk of occurring LVH compared with those in low tertile (high tertile: OR = 2.780, 95% CI: 1.945-3.975, p < 0.001). CONCLUSION: Plasma homocysteine levels were independently associated with LVMI in hypertensive patients with normal eGFR.


Assuntos
Hipertensão , Hipertrofia Ventricular Esquerda , Masculino , Feminino , Humanos , Estudos Transversais , Hipertensão/complicações , Análise de Regressão , Rim
2.
Sens Actuators B Chem ; 379: 133223, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36573100

RESUMO

Severe acute respiratory syndrome coronavirus (SARS-CoV-2) is rampant all over the world, and rapid and effective virus detection is the best auxiliary to curb the spread of the epidemic. A diagnosis can only be made if two or more different nucleic acid sequences are confirmed at the same time, and in most of traditional detection technologies, these target sequences have been detected separately. In this work, an electrochemiluminescent (ECL) biosensor employing a single ECL probe as signal output and responding to dual-target simultaneously is proposed for the first time. Taking the two sequences located in ORF 1ab region and N region of SARS-CoV-2 gene sequence as the model target and nitrogen doped carbon quantum dots (CDs) as ECL beacon, supplemented with catalytic hairpin assembly (CHA) reaction for signal amplification, the presented strategy has been successfully applied to the rapid detection of SARS-CoV-2. The developed SARS-CoV-2 biosensor based on the series CHA systems can realize the quantitative determination of SARS-CoV-2 in the range of 50 fM to 200 pM within 40 min. Moreover, the clinical validity of this method has been verified by the high consistency between the detection results of using this method and those using RT-qPCR for seven clinical pharyngeal swab samples.

3.
Sensors (Basel) ; 22(14)2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35890868

RESUMO

Because of its unique characteristics of small specific gravity, high strength, and corrosion resistance, the carbon fiber sucker rod has been widely used in petroleum production. However, there is still a lack of corresponding online testing methods to detect its integrity during the process of manufacturing. Ultrasonic nondestructive testing has become one of the most accepted methods for inspection of homogeneous and fixed-thickness composites, or layered and fixed-interface-shape composites, but a carbon fiber sucker rod with multi-layered structures and irregular interlayer interfaces increases the difficulty of testing. In this paper, a novel defect detection method based on multi-sensor information fusion and a deep belief network (DBN) model was proposed to identify online its defects. A water-immersed ultrasonic array with 32 ultrasonic probes was designed to realize the online and full-coverage scanning of carbon fiber rods in radial and axial positions. Then, a multi-sensor information fusion method was proposed to integrate amplitudes and times-of-flight of the received ultrasonic pulse-echo signals with the spatial angle information of each probe into defect images with obvious defects including small cracks, transverse cracks, holes, and chapped cracks. Three geometric features and two texture features from the defect images characterizing the four types of defects were extracted. Finally, a DBN-based defect identification model was constructed and trained to identify the four types of defects of the carbon fiber rods. The testing results showed that the defect identification accuracy of the proposed method was 95.11%.

4.
Proc Natl Acad Sci U S A ; 115(51): 12985-12990, 2018 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-30509977

RESUMO

Membrane proteins function in native cell membranes, but extraction into isolated particles is needed for many biochemical and structural analyses. Commonly used detergent-extraction methods destroy naturally associated lipid bilayers. Here, we devised a detergent-free method for preparing cell-membrane nanoparticles to study the multidrug exporter AcrB, by cryo-EM at 3.2-Å resolution. We discovered a remarkably well-organized lipid-bilayer structure associated with transmembrane domains of the AcrB trimer. This bilayer patch comprises 24 lipid molecules; inner leaflet chains are packed in a hexagonal array, whereas the outer leaflet has highly irregular but ordered packing. Protein side chains interact with both leaflets and participate in the hexagonal pattern. We suggest that the lipid bilayer supports and harmonizes peristaltic motions through AcrB trimers. In AcrB D407A, a putative proton-relay mutant, lipid bilayer buttresses protein interactions lost in crystal structures after detergent-solubilization. Our detergent-free system preserves lipid-protein interactions for visualization and should be broadly applicable.


Assuntos
Membrana Celular/metabolismo , Detergentes/metabolismo , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/química , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Membrana Celular/química , Cristalografia por Raios X , Detergentes/química , Escherichia coli/crescimento & desenvolvimento , Nanopartículas/química , Nanopartículas/metabolismo , Conformação Proteica
5.
Mol Pharm ; 14(10): 3499-3511, 2017 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-28858508

RESUMO

Candidate drugs to counter intracellular polymerization of deoxygenated sickle hemoglobin (Hb S) continue to represent a promising approach to mitigating the primary cause of the pathophysiology associated with sickle cell disease (SCD). One such compound is the naturally occurring antisickling agent, 5-hydroxymethyl-2-furfural (5-HMF), which has been studied in the clinic for the treatment of SCD. As part of our efforts to develop novel efficacious drugs with improved pharmacologic properties, we structurally modified 5-HMF into 12 ether and ester derivatives. The choice of 5-HMF as a pharmacophore was influenced by a combination of its demonstrated attractive hemoglobin modifying and antisickling properties, well-known safety profiles, and its reported nontoxic major metabolites. The derivatives were investigated for their time- and/or dose-dependent effects on important antisickling parameters, such as modification of hemoglobin, corresponding changes in oxygen affinity, and inhibition of red blood cell sickling. The novel test compounds bound and modified Hb and concomitantly increased the protein affinity for oxygen. Five of the derivatives exhibited 1.5- to 4.0-fold higher antisickling effects than 5-HMF. The binding mode of the compounds with Hb was confirmed by X-ray crystallography and, in part, helps explain their observed biochemical properties. Our findings, in addition to the potential therapeutic application, provide valuable insights and potential guidance for further modifications of these (and similar) compounds to enhance their pharmacologic properties.


Assuntos
Anemia Falciforme/tratamento farmacológico , Antidrepanocíticos/farmacologia , Desenho de Fármacos , Furaldeído/análogos & derivados , Hemoglobina Falciforme/metabolismo , Anemia Falciforme/sangue , Antidrepanocíticos/síntese química , Antidrepanocíticos/uso terapêutico , Química Farmacêutica , Cristalização , Cristalografia por Raios X , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Ésteres/química , Éteres/química , Furaldeído/química , Furaldeído/farmacologia , Furaldeído/uso terapêutico , Voluntários Saudáveis , Humanos , Modelos Moleculares , Oxigênio/metabolismo , Ligação Proteica , Relação Estrutura-Atividade , Fatores de Tempo , Resultado do Tratamento
6.
Biochemistry ; 54(49): 7178-92, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26582149

RESUMO

We have developed novel nitric oxide (NO)-releasing prodrugs of efaproxiral (RSR13) for their potential therapeutic applications in a variety of diseases with underlying ischemia. RSR13 is an allosteric effector of hemoglobin (Hb) that decreases the protein's affinity for oxygen, thereby increasing tissue oxygenation. NO, because of its vasodilatory property, in the form of ester prodrugs has been found to be useful in managing several cardiovascular diseases by increasing blood flow and oxygenation in ischemic tissues. We synthesized three NO-donor ester derivatives of RSR13 (DD-1, DD-2, and DD-3) by attaching the NO-releasing moieties nitrooxyethyl, nitrooxypropyl, and 1-(pyrrolidin-1-yl)diazen-1-ium-1,2-diolate, respectively, to the carboxylate of RSR13. In vitro studies demonstrated that the compounds released NO in a time-dependent manner upon being incubated with l-cysteine (1.8-9.3%) or human serum (2.3-52.5%) and also reduced the affinity of Hb for oxygen in whole blood (ΔP50 of 4.9-21.7 mmHg vs ΔP50 of 25.4-32.1 mmHg for RSR13). Crystallographic studies showed RSR13, the hydrolysis product of the reaction between DD-1 and deoxygenated Hb, bound to the central water cavity of Hb. Also, the hydrolysis product, NO, was observed exclusively bound to the two α hemes, the first such HbNO structure to be reported, capturing the previously proposed physiological bis-ligated nitrosylHb species. Finally, nitrate was observed bound to ßHis97. Ultraperformance liquid chromatography-mass spectrometry analysis of the compounds incubated with matrices used for the various studies demonstrated the presence of the predicted reaction products. Our findings, beyond the potential therapeutic application, provide valuable insights into the biotransformation of NO-releasing prodrugs and their mechanism of action and into hemoglobin-NO biochemistry at the molecular level.


Assuntos
Compostos de Anilina , Hemoglobinas/metabolismo , Óxido Nítrico , Pró-Fármacos , Propionatos , Vasodilatadores , Compostos de Anilina/síntese química , Compostos de Anilina/química , Compostos de Anilina/farmacocinética , Biotransformação , Feminino , Hemoglobinas/química , Humanos , Hidrólise , Masculino , Óxido Nítrico/química , Óxido Nítrico/farmacocinética , Pró-Fármacos/síntese química , Pró-Fármacos/química , Pró-Fármacos/farmacocinética , Propionatos/síntese química , Propionatos/química , Propionatos/farmacocinética , Vasodilatadores/síntese química , Vasodilatadores/química , Vasodilatadores/farmacocinética
7.
Bioorg Med Chem Lett ; 25(17): 3721-5, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26096680

RESUMO

Prostate cancer is one of the leading causes of death among males in the world. Prostate cancer cells have been shown to express upregulated chemokine receptor CCR5, a G protein-coupled receptor (GPCR) that relates to the inflammation process. Anibamine, a natural product containing a pyridine ring and two aliphatic side chains, was shown to carry a binding affinity of 1 µM at CCR5 as an antagonist with potential anti-cancer activity. However, it is not drug-like according to the Lipinski's rule of five mainly due to its two long aliphatic side chains. In our effort to improve its drug-like property, a series of anibamine derivatives were designed and synthesized by placement of aromatic side chains through an amide linkage to the pyridine ring. The newly synthesized compounds were tested for their CCR5 affinity and antagonism, and potential anti-proliferation activity against prostate cancer cell lines. Basal cytotoxicity was finally studied for compounds showing potent anti-proliferation activity. It was found that compounds with hydrophobic substitutions on the aromatic systems seemed to carry more promising CCR5 binding and prostate cancer cell proliferation inhibition activities.


Assuntos
Antineoplásicos/farmacologia , Antagonistas dos Receptores CCR5/química , Antagonistas dos Receptores CCR5/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Piridinas/química , Animais , Antineoplásicos/química , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Técnicas de Química Sintética , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Humanos , Masculino , Camundongos , Simulação de Acoplamento Molecular , Células NIH 3T3/efeitos dos fármacos , Neoplasias da Próstata/patologia , Receptores CCR5/química , Receptores CCR5/metabolismo , Relação Estrutura-Atividade
8.
Sensors (Basel) ; 14(5): 8513-27, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24834907

RESUMO

A Highway Intelligent Space System (HISS) is proposed to study vehicle environment perception in this paper. The nature of HISS is that a space sensors system using laser, ultrasonic or radar sensors are installed in a highway environment and communication technology is used to realize the information exchange between the HISS server and vehicles, which provides vehicles with the surrounding road information. Considering the high-speed feature of vehicles on highways, when vehicles will be passing a road ahead that is prone to accidents, the vehicle driving state should be predicted to ensure drivers have road environment perception information in advance, thereby ensuring vehicle driving safety and stability. In order to verify the accuracy and feasibility of the HISS, a traditional vehicle-mounted sensor system for environment perception is used to obtain the relative driving state. Furthermore, an inter-vehicle dynamics model is built and model predictive control approach is used to predict the driving state in the following period. Finally, the simulation results shows that using the HISS for environment perception can arrive at the same results detected by a traditional vehicle-mounted sensors system. Meanwhile, we can further draw the conclusion that using HISS to realize vehicle environment perception can ensure system stability, thereby demonstrating the method's feasibility.


Assuntos
Redes de Comunicação de Computadores/instrumentação , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Veículos Automotores , Processamento de Sinais Assistido por Computador/instrumentação , Transdutores , Tecnologia sem Fio/instrumentação , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Armazenamento e Recuperação da Informação/métodos , Modelos Teóricos
9.
Biochemistry ; 52(44): 7707-13, 2013 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-24116866

RESUMO

The Pin1 peptidyl-prolyl isomerase catalyzes isomerization of pSer/pThr-Pro motifs in regulating the cell cycle. Peptide substrates, Ac-Phe-Phe-phosphoSer-Pro-Arg-p-nitroaniline, were synthesized in unlabeled form, and with deuterium-labeled Ser-d3 and Pro-d7 amino acids. Kinetic data were collected as a function of Pin1 concentration to measure kinetic isotope effects (KIEs) on catalytic efficiency (kcat/Km). The normal secondary (2°) KIE value measured for the Ser-d3 substrate (kH/kD = 1.6 ± 0.2) indicates that the serine carbonyl does not rehybridize from sp(2) to sp(3) in the rate-determining step, ruling out a nucleophilic addition mechanism. The normal 2° KIE can be explained by hyperconjugation between Ser α-C-H/D and C═O and release of steric strain upon rotation of the amide bond from cis to syn-exo. The inverse 2° KIE value (kH/kD = 0.86 ± 0.08) measured for the Pro-d7 substrate indicates rehybridization of the prolyl nitrogen from sp(2) to sp(3) during the rate-limiting step of isomerization. No solvent kinetic isotope was measured by NMR exchange spectroscopy (kH2O/kD2O = 0.92 ± 0.12), indicating little or no involvement of exchangeable protons in the mechanism. These results support the formation of a simple twisted amide transition state as the mechanism for peptidyl prolyl isomerization catalyzed by Pin1. A model of the reaction mechanism is presented using crystal structures of Pin1 with ground state analogues and an inhibitor that resembles a twisted amide transition state.


Assuntos
Amidas/química , Dineínas do Citoplasma/química , Deutério/química , Isomerismo , Marcação por Isótopo , Cinética , Peptídeos/química , Especificidade por Substrato
10.
J Hum Hypertens ; 37(3): 227-234, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35277588

RESUMO

Information on the association between homocysteine (HCY) levels and carotid atherosclerosis (CAS) in hypertension (HTN) is limited. A cross-sectional study was performed to examine the relationship of plasma HCY concentration with CAS in 1700 hypertensives (61.62 ± 12.16 year). The prevalence of CAS and carotid intima-media thickness (CIMT) progressively increased across quartiles of HCY levels (P < 0.001). Correlation analysis showed significantly positive correlation between HCY and CAS (r = 0.261, P < 0.001). In a logistic regression, HCY independently predicted the presence of CAS (OR 1.284, 95% CI 1.163-1.418). Further investigation revealed that interaction effect of HCY was substantial for gender (P for interaction 0.023), age (P for interaction <0.001) and smoking (P for interaction 0.025) on CAS. Thus, in hypertensives, those of male, aged ≥55 year and current smokers, in which HCY ≥ 13.49 µmol/L were more likely to suffer CAS, suggesting a role of HCY in the development and progression of CAS in these patients, and HCY determination should be recommended to better stratify the cardiovascular risk.


Assuntos
Doenças das Artérias Carótidas , Hipertensão , Humanos , Masculino , Espessura Intima-Media Carotídea , Estudos Transversais , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Hipertensão/complicações , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/epidemiologia , Homocisteína , Fatores de Risco
11.
J Clin Hypertens (Greenwich) ; 25(10): 923-931, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37667509

RESUMO

Even though as a gold standard for noninvasive measurement of arterial stiffness, carotid-femoral pulse wave velocity (cfPWV) is not widely used in primary healthcare institutions due to time-consuming and unavailable equipment. The aim of this study was to develop a convenient and low-cost nomogram model for arterial stiffness screening. A cross-sectional study was undertaken in the department of general practice, the First Affiliated Hospital of Fujian Medical University. Arterial stiffness was defined as cfPWV ≥ 10 m/s. A total of 2717 participants were recruited to construct the nomogram using the least absolute shrinkage and selection operator and logistic regressions. Receiver operating characteristic (ROC) curve, calibration curve, decision curve analysis, clinical impact curve were used to evaluate the performance of the model. The model was validated internally and externally (399 participants) by bootstrap method. Arterial stiffness was identified in 913 participants (33.60%). Age, sex, waist to hip ratio, systolic blood pressure, duration of diabetes, heart rate were selected to construct the nomogram model. Good discrimination and accuracy were exhibited with area under curve of 0.820 (95% CI 0.803-0.837) in ROC curve and mean absolute error = 0.005 in calibration curve. A positive net benefit was shown in decision curve analysis and clinical impact curve. A satisfactory agreement was displayed in internal validation and external validation. The low cost and user-friendly nomogram is suitable for arterial stiffness screening in primary healthcare institutions.

12.
Blood Press Monit ; 27(4): 239-246, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35383582

RESUMO

OBJECTIVE: Although orthostatic hypotension (OH) and orthostatic hypertension (OHT) can independently predict cardiovascular events, the underlying mechanisms remain controversial. Our study aimed to examine the relationships between orthostatic blood pressure (BP) changes and arterial stiffness. METHODS: In this cross-sectional analysis, 1820 participants were divided into three groups according to BP changes within 3 min of orthostatism: the OH group had a decrease of >20 mmHg in SBP or >10 mmHg in DBP, the OHT group had an increase of ≥20 mmHg in SBP, and the orthostatic normotensive (ONT) group had normal changes. Arterial stiffness was assessed by measuring the carotid-femoral pulse wave velocity (cfPWV). RESULTS: OH and OHT were observed in 257 (14.1%) and 62 (3.4%) participants, respectively. Subjects in the OH group were significantly older, were more likely to have hypertension and diabetes, and had higher cfPWV than those in the ONT group ( P < 0.05); however, no differences were found between the ONT and OHT groups. Stepwise multiple regression analysis of the subgroups stratified by hypertension and diabetes revealed that age was related to increased cfPWV in all stratifications, and the change in SBP was significantly positively correlated with cfPWV in hypertensive subjects; however, this association was not observed in nonhypertensive subjects. CONCLUSION: We found that arterial stiffness was closely related to OH but not to OHT. In addition to expanding current knowledge of the relationship between orthostatic BP changes and arterial stiffness, our study underlines the importance of age, SBP changes, and hypertension in evaluating arterial stiffness.


Assuntos
Hipertensão , Hipotensão Ortostática , Rigidez Vascular , Pressão Sanguínea/fisiologia , Estudos Transversais , Humanos , Análise de Onda de Pulso , Rigidez Vascular/fisiologia
13.
Biochemistry ; 50(44): 9545-50, 2011 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-21980916

RESUMO

The mechanism of the cell cycle regulatory peptidyl prolyl isomerase (PPIase), Pin1, was investigated using reduced-amide inhibitors designed to mimic the twisted-amide transition state. Inhibitors, R-pSer-Ψ[CH(2)N]-Pro-2-(indol-3-yl)ethylamine, 1 [R = fluorenylmethoxycarbonyl (Fmoc)] and 2 (R = Ac), of Pin1 were synthesized and bioassayed. Inhibitor 1 had an IC(50) value of 6.3 µM, which is 4.5-fold better for Pin1 than our comparable ground-state analogue, a cis-amide alkene isostere-containing inhibitor. The change of Fmoc to Ac in 2 improved aqueous solubility for structural determination and resulted in an IC(50) value of 12 µM. The X-ray structure of the complex of 2 bound to Pin1 was determined to 1.76 Å resolution. The structure revealed that the reduced amide adopted a conformation similar to the proposed twisted-amide transition state of Pin1, with a trans-pyrrolidine conformation of the prolyl ring. A similar conformation of substrate would be destabilized relative to the planar amide conformation. Three additional reduced amides, with Thr replacing Ser and l- or d-pipecolate (Pip) replacing Pro, were slightly weaker inhibitors of Pin1.


Assuntos
Amidas/química , Inibidores Enzimáticos/química , Peptidilprolil Isomerase/antagonistas & inibidores , Amidas/síntese química , Amidas/metabolismo , Cristalografia por Raios X , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/metabolismo , Humanos , Peptidilprolil Isomerase de Interação com NIMA , Oxirredução , Peptidilprolil Isomerase/química , Peptidilprolil Isomerase/metabolismo , Ligação Proteica , Conformação Proteica , Pirrolidinas/química , Estereoisomerismo
14.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 28(4): 768-73, 2011 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-21936378

RESUMO

In this study we synthesized a micro- and mesoporous material, SBA-16. And later on we functionalized it with octyltrimethoxysilane and octadecyltrimethoxysilane, respectively. The materials of SBA-16 and its functionalized form were characterized by nitrogen adsorption isotherms at 77K, small angle X-ray scattering (SAXS), Fourier-transform infrared (FT-IR), thermal gravimetric analysis (TGA), and adsorption isotherms of single component n-heptane, toluene and water vapour. The data of FT-IR and TGA demonstrated the successful chemical modification of surface and porous wall of SBA-16 with different hydrocarbon chains. The results of SAXS, nitrogen adsorption at 77K, and adsorption isotherms of probe molecules revealed that the functionalized SBA-16 materials possessed relatively less regularity, smaller BET surface area and pore volumes, and lower adsorption capacities for the probe molecules compared to the original SBA-16. However, the functionalized SBA-16 materials showed much less affinity to polar molecules such as water. This work provides useful fundamental information for future study of novel mesoporous silica materials as potential drug delivery carriers.


Assuntos
Portadores de Fármacos , Dióxido de Silício/química , Adsorção , Portadores de Fármacos/química , Porosidade , Propriedades de Superfície
15.
J Clin Hypertens (Greenwich) ; 23(1): 128-136, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33283950

RESUMO

Lactate dehydrogenase (LDH) has been reported to be positively correlated with albuminuria assessed by urinary albumin-to-creatinine ratio (UACR) in patients with sickle cell disease; both LDH and albuminuria are positively associated with the severity of hypertension (HTN). Here, a cross-sectional study was performed to investigate the association between LDH and albuminuria in Chinese hypertensives. A total of 1169 Chinese individuals (aged 58.0 ± 11.5 years, 60.4% male), who were admitted to our hospital, were included in this study. Based on the level of LDH, all hypertensives (n = 802) were divided into three groups: HTN1 (lowest tertile of LDH, n = 264), HTN2 (mediate tertile of LDH, n = 268), and HTN3 (highest tertile of LDH, n = 270). Hypertensives with hyperhomocysteinemia were defined as hypertensives with homocysteine ≥15µmol/L. Meanwhile, 367 normotensives served as controls. Compared with normotensives, the levels of LDH and UACR were significantly higher in hypertensives (p < .05). There was an increasing trend of albuminuria (UACR ≥30 mg/g) from control, HTN1, HTN2 to HTN3 group (4% vs. 12.1% vs. 14.9% vs. 19.6%, χ2  = 38.886, p < .001). Stepwise multiple regression analysis showed an independent association between LDH and UACR in patients with HTN (ß = 0.085, p < .05), but not in normotensives. After further stratification in hypertensive patients, this correlation remained in the male (ß = 0.161, p < .001), elderly (age ≥65 years, ß = 0.174, p < .001) and especially hypertensives with hyperhomocysteinemia (ß = 0.402, p < .001). LDH combined with white blood cell (WBC) counts was observed to have better discrimination for albuminuria than creatinine united with cystatin C in hypertensives according to receiver operation characteristic curves (area under curve: 0.637 vs. 0.535, z = 2.563, p = .0104). In conclusion, the level of LDH was associated with albuminuria in Chinese patients with HTN, particularly in hypertensives with hyperhomocysteinemia. LDH combined with WBC provided better prediction of albuminuria than routine renal function assessment in hypertensives. Further studies are needed to confirm LDH as an early marker for the risk of kidney involvement among hypertensives.


Assuntos
Albuminúria , Hipertensão , Idoso , Albuminúria/diagnóstico , Albuminúria/epidemiologia , China/epidemiologia , Creatinina , Estudos Transversais , Feminino , Humanos , L-Lactato Desidrogenase , Masculino
16.
Biosens Bioelectron ; 147: 111789, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31655383

RESUMO

A novel electrochemiluminescence (ECL) biosensor was developed for high sensitive and selective detection of miRNA-21 based on the efficient and specific toehold-mediated strand displacement (TMSD) amplification with Ru(phen)32+ loaded DNA nanoclews (NCs-Ru(phen)32+) as signal tags. The stable DNA nanoclews, synthesized by a simple rolling circle amplification reaction, were employed to load with Ru(phen)32+ efficiently as ECL signal tags to amplify the signals. As for TMSD, the substrate strand (Sub) was initially hybridized with P1 and P2 to form DNA duplex structures with a toehold 1. miRNA-21 could hybridize with the toehold 1 and trigger the TMSD amplification with the help of assist strand, releasing lots of P1 stands from DNA duplex structures. The TMSD technique realized the converting and amplification of the single miRNA-21 input to lots of output DNA (namely P1) with good selectivity, simultaneously. Output P1 were designed to expand the stem-locked region of HP, which were immobilized on the Au electrodes firstly. Subsequently, the opened HP could hybridize with the Ru(phen)32+, capturing the ECL signal tags closed to the sensing surface. The ECL intensity of the system had a linear relationship with the logarithm of the miRNA-21 concentration in the range of 1.0 fM to 100 pM with a limit of detection of 0.65 fM. The strategy was further applied to detect miRNA-21 in complex samples, and the result was consistent with the qRT-PCR.


Assuntos
Técnicas Biossensoriais , DNA/química , Técnicas Eletroquímicas , MicroRNAs/isolamento & purificação , Aptâmeros de Nucleotídeos/química , Humanos , Medições Luminescentes , Nanopartículas Metálicas/química , MicroRNAs/química , Técnicas de Amplificação de Ácido Nucleico , Fotometria
17.
Biosci Rep ; 40(1)2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-31840737

RESUMO

The overall survival rate of patients with hepatocellular carcinoma (HCC) has remained unchanged over the last several decades. Therefore, novel drugs and therapies are required for HCC treatment. Isoliquiritigenin (ISL), a natural flavonoid predominantly isolated from the traditional Chinese medicine Glycyrrhizae Radix (Licorice), has a high anticancer potential and broad application value in various cancers. Here, we aimed to investigate the anticancer role of ISL in the HCC cell line Hep3B. Functional analysis revealed that ISL inhibited the proliferation of Hep3B cells by causing G1/S cell cycle arrest in vitro. Meanwhile, the inhibitory effect of ISL on proliferation was also observed in vivo. Further analysis revealed that ISL could suppress the migration and metastasis of Hep3B cells in vitro and in vivo. Mechanistic analysis revealed that ISL inhibited cyclin D1 and up-regulated the proteins P21, P27 that negatively regulate the cell cycle. Furthermore, ISL induced apoptosis while inhibiting cell cycle transition. In addition, phosphatidylinositol 3'-kinase/protein kinase B (PI3K/AKT) signal pathway was suppressed by ISL treatment, and the epithelial marker E-cadherin was up-regulated when the mesenchymal markers Vimentin and N-cadherin were down-regulated. In brief, our findings suggest that ISL could be a promising agent for preventing HCC tumorigenesis and metastasis.


Assuntos
Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Chalconas/farmacologia , Ciclina D1/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Feminino , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus
18.
Sci Rep ; 10(1): 20277, 2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-33219275

RESUMO

Sickle cell disease (SCD) results from a hemoglobin (Hb) mutation ßGlu6 → ßVal6 that changes normal Hb (HbA) into sickle Hb (HbS). Under hypoxia, HbS polymerizes into rigid fibers, causing red blood cells (RBCs) to sickle; leading to numerous adverse pathological effects. The RBC sickling is made worse by the low oxygen (O2) affinity of HbS, due to elevated intra-RBC concentrations of the natural Hb effector, 2,3-diphosphoglycerate. This has prompted the development of Hb modifiers, such as aromatic aldehydes, with the intent of increasing Hb affinity for O2 with subsequent prevention of RBC sickling. One such molecule, Voxelotor was recently approved by U.S. FDA to treat SCD. Here we report results of a novel aromatic aldehyde, VZHE-039, that mimics both the O2-dependent and O2-independent antisickling properties of fetal hemoglobin. The latter mechanism of action-as elucidated through crystallographic and biological studies-is likely due to disruption of key intermolecular contacts necessary for stable HbS polymer formation. This dual antisickling mechanism, in addition to VZHE-039 metabolic stability, has translated into significantly enhanced and sustained pharmacologic activities. Finally, VZHE-039 showed no significant inhibition of several CYPs, demonstrated efficient RBC partitioning and high membrane permeability, and is not an efflux transporter (P-gp) substrate.


Assuntos
Anemia Falciforme/tratamento farmacológico , Antidrepanocíticos/farmacologia , Eritrócitos Anormais/efeitos dos fármacos , Hemoglobina Falciforme/metabolismo , Multimerização Proteica/efeitos dos fármacos , Adulto , Anemia Falciforme/sangue , Antidrepanocíticos/uso terapêutico , Células CACO-2 , Hipóxia Celular , Cristalografia por Raios X , Avaliação Pré-Clínica de Medicamentos , Eritrócitos Anormais/metabolismo , Hemoglobina Falciforme/genética , Humanos , Modelos Moleculares , Oxigênio/metabolismo
19.
Drug News Perspect ; 22(7): 399-407, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19890497

RESUMO

Pin1 specifically catalyzes the cis/trans isomerization of phospho-Ser/Thr-Pro bonds and plays an important role in many cellular events through the effects of conformational change on the function of its biological substrates, including cell division cycle 25 C (Cdc25C), c-Jun and p53. Pin1 is overexpressed in many human cancer tissues, including breast, prostate and lung cancer. Its expression correlates with cyclin D1 levels, which contribute to cell transformation. Overexpression of Pin1 promotes tumor growth, while inhibition of Pin1 causes tumor cell apoptosis. Pin1 plays an important role in oncogenesis and therefore may serve as an effective anticancer target. Many inhibitors of Pin1 have been discovered, including several classes of designed inhibitors (alkene isosteres, reduced amides, indanyl ketones) and natural products (juglone, pepticinnamin E analogues, PiB and its derivatives obtained from a library screen). Pin1 inhibitors could be used as a novel type of anticancer drug by blocking cell cycle progression. Therefore, Pin1 represents a new diagnostic and therapeutic anticancer drug target.


Assuntos
Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/genética , Peptidilprolil Isomerase/efeitos dos fármacos , Peptidilprolil Isomerase/genética , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Animais , Ciclo Celular/efeitos dos fármacos , Dano ao DNA , Humanos , Peptidilprolil Isomerase de Interação com NIMA , Neoplasias/diagnóstico , Peptidilprolil Isomerase/metabolismo , Peptidilprolil Isomerase/fisiologia
20.
Aging (Albany NY) ; 11(21): 9709-9718, 2019 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-31711045

RESUMO

This study aimed to investigate whether plasma homocysteine levels were associated with carotid-femoral pulse wave velocity (cfPWV), a golden standard of arterial stiffness, in a population from southern China. A cross-sectional study was conducted on 713 patients admitted to the First Affiliated Hospital of Fujian Medical University from February 2016 to August 2017. They were divided into four groups based on gender-specific quartile of homocysteine levels. Age, cfPWV, uric acid levels, and percentage of hypertension increased with ascending quartiles. The duration of hypertension and systolic blood pressure were higher in the highest quartile than in the lowest quartile. Pearson's correlation analysis and multivariate regression showed a correlation of homocysteine levels with cfPWV. A nearly twofold increased risk of cfPWV ≥10 m/s was observed in the highest quartile compared with the lowest quartile (in the highest quartile: odds ratio = 2.917, 95% confidence interval: 1.635-5.202, P < 0.001). After stratification, this correlation was present in both sexes, in patients aged over 65 years, and those with hypertension. The plasma homocysteine levels were independently associated with cfPWV in the population from southern China, especially in the elderly and those with hypertension.


Assuntos
Velocidade da Onda de Pulso Carótido-Femoral , Homocisteína/sangue , Idoso , Povo Asiático , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA