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1.
J Sci Food Agric ; 104(12): 7281-7290, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38655901

RESUMO

BACKGROUND: Whey protein isolate (WPI) generally represents poor functional properties such as thermal stability, emulsifying activity and antioxidant activity near its isoelectric point or high temperatures, which limit its application in the food industry. The preparation of WPI-polysaccharide covalent conjugates based on Maillard reaction is a promising method to improve the physical and chemical stability and functional properties of WPI. In this research, WPI-inulin conjugates were prepared through wet heating method and ultrasound method and their structural and functional properties were examined. RESULTS: In conjugates, the free amino acid content was reduced, the high molecular bands were emerged at sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), new C-N bonds were formed in Fourier-transform infrared (FTIR) spectroscopy, and fluorescence intensity was reduced compared with WPI. Furthermore, the result of circular dichroism (CD) spectroscopy also showed that the secondary structure of conjugates was changed. Conjugates with ultrasound treatment had better structural properties compared with those prepared by wet heating treatment. The functional properties such as thermal stability, emulsifying activity index (EAI), emulsion stability (ES) and antioxidant activity of conjugates with wet heating treatment were significantly improved compared with WPI. The EAI and ES of conjugates with ultrasound treatment were the highest, but the thermal stability and antioxidant activity were only close to that of the conjugates with wet heating treatment for 2 h. CONCLUSION: This study revealed that WPI-inulin conjugates prepared with ultrasound or wet heating method not only changed the structural characteristics of WPI but also could promote its functional properties including thermal stability, EAI, ES and antioxidant activity. © 2024 Society of Chemical Industry.


Assuntos
Antioxidantes , Emulsões , Temperatura Alta , Proteínas do Soro do Leite , Proteínas do Soro do Leite/química , Antioxidantes/química , Emulsões/química , Reação de Maillard , Calefação
2.
Opt Express ; 30(4): 6003-6015, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35209548

RESUMO

All-day passive radiative cooling has recently attracted broader attention for its potential as a viable energy technology. Although tremendous progress has been achieved, the design and fabrication of low-cost high-efficiency radiators for all-day passive radiative cooling remains a challenge. Herein, we report a new type of flexible composite radiator film with built-in artificial opal-like structures for all-day passive radiative cooling. Using artificial opal structure concepts, the proposed polydimethylsiloxane (PDMS) radiator film with embedded polystyrene (PS) microsphere photonic crystals exhibits a sufficiently high solar reflectance of ∼92.7% when in a direct sunlight region, and a thermal emittance of ∼93.6% within the atmospheric window. Without the need for traditional reflectors like silver or aluminum foils, this composite film realizes subambient temperature reduction of ∼4.8 °C in direct sunlight and ∼8.5 °C during the night. This work provides a new fabrication approach for the low-cost production of structural polymer films for high performance and potential real word applications.

3.
Eur Radiol ; 31(7): 5434-5441, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33475772

RESUMO

OBJECTIVE: To develop machine learning (ML) models capable of predicting ICU admission and extended length of stay (LOS) after torso (chest, abdomen, or pelvis) trauma, by using clinical and/or imaging data. MATERIALS AND METHODS: This was a retrospective study of 840 adult patients admitted to a level 1 trauma center after injury to the torso over the course of 1 year. Clinical parameters included age, sex, vital signs, clinical scores, and laboratory values. Imaging data consisted of any injury present on CT. The two outcomes of interest were ICU admission and extended LOS, defined as more than the median LOS in the dataset. We developed and tested artificial neural network (ANN) and support vector machine (SVM) models, and predictive performance was evaluated by area under the receiver operating characteristic (ROC) curve (AUC). RESULTS: The AUCs of SVM and ANN models to predict ICU admission were up to 0.87 ± 0.03 and 0.78 ± 0.02, respectively. The AUCs of SVM and ANN models to predict extended LOS were up to 0.80 ± 0.04 and 0.81 ± 0.05, respectively. Predictions based on imaging alone or imaging with clinical parameters were consistently more accurate than those based solely on clinical parameters. CONCLUSIONS: The best performing models incorporated imaging findings and outperformed those with clinical findings alone. ML models have the potential to help predict outcomes in trauma by integrating clinical and imaging findings, although further research may be needed to optimize their performance. KEY POINTS: • Artificial neural network and support vector machine-based models were used to predict the intensive care unit admission and extended length of stay after trauma to the torso. • Our input data consisted of clinical parameters and CT imaging findings derived from radiology reports, and we found that combining the two significantly enhanced the prediction of both outcomes with either model. • The highest accuracy (83%) and highest area under the receiver operating characteristic curve (0.87) were obtained for artificial neural networks and support vector machines, respectively, by combining clinical and imaging features in the prediction of intensive care unit admission.


Assuntos
Unidades de Terapia Intensiva , Aprendizado de Máquina , Adulto , Humanos , Tempo de Internação , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Tronco
4.
Anal Chem ; 92(10): 7146-7153, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32297736

RESUMO

Metallic nanoclusters (NCs) have molecular-like structures and unique physical and chemical properties, making them an interesting new class of luminescent nanomaterials with various applications in chemical sensing, bioimaging, optoelectronics, light-emitting diodes (LEDs), etc. However, weak photoluminescence (PL) limits the practical applications of NCs. Herein, an effective and facile strategy of enhancing the PL of NCs was developed using Ag shell-isolated nanoparticle (Ag SHIN)-enhanced luminescence platforms with tuned SHINs shell thicknesses. 3D-FDTD theoretical calculations along with femtosecond transient absorption and fluorescence decay measurements were performed to elucidate the enhancement mechanisms. Maximum enhancements of up to 231-fold for the [Au7Ag8(C≡CtBu)12]+ cluster and 126-fold for DNA-templated Ag NCs (DNA-Ag NCs) were achieved. We evidenced a novel and versatile method of achieving large PL enhancements with NCs with potential for practical biosensing applications for identifying target DNA in ultrasensitive surface analysis.

5.
Ecotoxicol Environ Saf ; 195: 110459, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32182533

RESUMO

This work was conducted to study the effect of soil pH (4.0, 6.0, and 8.0) on the transport, fractionation, and oxidation of trivalent chromium [Cr(III)]. Variation in pH altered soil chemical and mineralogical properties such as zeta potential, cation exchange capacity and redox potential of natural soil. Breakthrough curves and batch sorption experiments coupled with fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analyses demonstrated that the easy mobility of Cr(III) in pH 4.0 soil was dominated by the limited coordination effect. The high retention of Cr(III) in pH 8.0 soil was mainly ascribed to the hydrolysis. Incubation experiments indicated that the proportions of Cr in exchangeable fraction decreased with increasing of soil pH and incubation time, and kinetics analysis revealed that the time dependent transformation was controlled by mass transfer and chemical processes (e.g., hydrolysis, ion association). The XPS confirmed the oxidation of Cr(III) in pH 8.0 soil during the incubation period. Furthermore, the content of toxic hexavalent chromium [Cr(VI)] was positively associated with time and initial concentration of Cr(III) released. These results revealed the hazardousness of Cr(III) in soil contaminated simultaneously by inorganic acid and alkali.


Assuntos
Cromo/análise , Poluentes do Solo/análise , Solo/química , Adsorção , Cromo/química , Concentração de Íons de Hidrogênio , Cinética , Oxirredução , Espectroscopia Fotoeletrônica , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Eur Spine J ; 27(10): 2550-2564, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29923019

RESUMO

INTRODUCTION: Kyphoplasty has been widely used to treat vertebral compression fractures (VCFs). In standard procedure of kyphoplasty, two balloons were inserted into the vertebral body through bipedicular and inflated simultaneously, while using a single balloon two times is also a common method in clinic to lessen the financial burden of patients. However, the effect and safety of single balloon versus double balloon bipedicular kyphoplasty are still controversy. METHODS: In this systematic review and meta-analysis, eligible studies were identified through a comprehensive literature search of PubMed, Cochrane library EMBASE, Web of Science, Wanfang, CNKI, VIP and CBM until January 1, 2018. Results from individual studies were pooled using a random or fixed effects model. RESULTS: Seven articles were included in the systematic review and five studies were consisted in meta-analysis. We observed no significant difference between single balloon and double balloon bipedicular kyphoplasty in visual analog scale (VAS), angle (kyphotic angle and Cobb angle), consumption (operation time, cement volume and volume of bleeding), vertebral height (anterior height, medium height and posterior height) and complications (cement leakage and new VCFs), while the cost of single balloon bipedicular kyphoplasty is lower than that of double balloon bipedicular kyphoplasty. The results of our meta-analysis also demonstrated that single balloon can significantly improve the VAS, angle and vertebral height of patients suffering from VCFs. CONCLUSION: This systematic review and meta-analysis collectively concludes that single balloon bipedicular kyphoplasty is as effective as double balloon bipedicular kyphoplasty in improving clinical symptoms, deformity and complications of VCFs but not so expensive. These slides can be retrieved under Electronic Supplementary Material.


Assuntos
Fraturas por Compressão/cirurgia , Cifoplastia , Fraturas da Coluna Vertebral/cirurgia , Coluna Vertebral/cirurgia , Humanos , Cifoplastia/efeitos adversos , Cifoplastia/métodos , Cifoplastia/estatística & dados numéricos
7.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 49(2): 285-289, 2018 Mar.
Artigo em Zh | MEDLINE | ID: mdl-29737077

RESUMO

OBJECTIVE: To establish a method for the determination of 5-hydroxy tryptamine (5-HT),adrenalin (AD) and noradrenalin (NA) in human plasma using pre-column derivatization HPLC-MS/MS. Methods Derivatives of the plasma samples were produced with dansyl chloride under pH 10.5,and then extracted and enriched with ethyl acetate. The detected chemicals were separated using Ultimate C18 (50 mm×4.6 mm,5 µm) with acetonitrile-water-formic acid=95∶5∶0.05 (V∶V∶V) at 0.2 mL/min. The HPLC-MS//MS system was operated under a multiple reaction monitoring mode (MRM) using the electrospray ionization technique in positive mode. RESULTS: Linear range of the calibration curve appeared in 250-2.5 ng/mL. The method had a less than 9% intra- and inter-assay relative standard deviation (RSD),95.44%-109.71% recoveries,and 4.86%-12.81% matrix effects. CONCLUSION: This method is simple,accurate,and suitable for detection of 5-HT,AD and NA in human plasma.


Assuntos
Cromatografia Líquida de Alta Pressão , Epinefrina/sangue , Norepinefrina/sangue , Serotonina/sangue , Espectrometria de Massas em Tandem , Humanos , Reprodutibilidade dos Testes
8.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 49(1): 102-106, 2018 Jan.
Artigo em Zh | MEDLINE | ID: mdl-29737099

RESUMO

OBJECTIVE: To develop a high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method for the determination of voriconazole in human plasma and its bioequivalence. METHODS: 48 healthy male volunteers received a single dose of 200 mg voriconazole tablets in a two period (with two preparations) and randomized crossover bioequivalence study. Their plasma voriconazole was determined using HPLC-MS/MS. The pharmacokinetic parameters and bioequivalence of the two preparations were calculated with WinNonlin®6.1. RESULTS: The calibration curve of voriconazole ranged from 1 to 5 000 ng/mL. The HPLC-MS/MS method had less than 11% intra- and inter-day relative standard deviation (RSD),with 100.00% to 109.73% accuracies. The RSD of the matrix effect of voriconazole adjusted with internal standard was less than 15%. The extract recoveries exceeded 50% with good stability. The 90% confidence intervals for the peak concentration (Cmax) and the area under the curve (AUC0-t and AUC0-∞)of voriconazole fell into the bioequivalence range of 80.00%-125.00%. There was no significant difference in peak time (Tmax) between the two preparations. CONCLUSION: HPLC-MS/MS can be used for determination of voriconazole in human plasma. The two tested preparations of voriconazole are bioequivalent.


Assuntos
Equivalência Terapêutica , Voriconazol/sangue , Área Sob a Curva , Cromatografia Líquida de Alta Pressão , Estudos Cross-Over , Humanos , Masculino , Comprimidos , Espectrometria de Massas em Tandem , Voriconazol/farmacocinética
9.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 49(1): 107-112, 2018 Jan.
Artigo em Zh | MEDLINE | ID: mdl-29737100

RESUMO

OBJECTIVE: To develop a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for detecting tenofovir in human plasma. METHODS: Twenty four healthy male volunteers received a single oral dose of 300 mg tenofovir disoproxil fumarate tablets under fasting and high-fat diet conditions in a randomized four-way crossover bioequivalence study with two preparations of tablets. Plasma samples were taken and analyzed using the LC-MS/MS method. The pharmacokinetic parameters of the two preparations were calculated and compared statistically to evaluate their bioequivalence using Phoenix Winnonlin6.3. RESULTS: Linear detection responses were obtained for tenofovir at the range from 3.13 to 500 ng/mL. The intra- and inter-day precisions were high,with lower than 5.43% [relative standard deviation (RSD)%],high recovery and good stability. The 90% confidence intervals of peak concentration (Cmax) of tenofovir and its area under the curve (AUC0-t and AUC0-∞ ) all fell within the bioequivalence limit 80.00%-125.00% under both fasting and high-fat diet conditions. No significant difference in peak time (Tmax) was demonstrated between the two preparations (P>0.05) . CONCLUSION: The LC-MS/MS method can be used for simultaneous determination of tenofovir in human plasma. The two preparations of tablets are bioequivalent.


Assuntos
Tenofovir/sangue , Equivalência Terapêutica , Área Sob a Curva , Cromatografia Líquida , Estudos Cross-Over , Humanos , Masculino , Comprimidos , Espectrometria de Massas em Tandem , Tenofovir/farmacocinética
10.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 49(6): 929-933, 2018 Nov.
Artigo em Zh | MEDLINE | ID: mdl-32677407

RESUMO

OBJECTIVE: To study the pharmacokinetic profile of phentolamine mesylate injection in healthy Chinese volunteers. METHODS: A total of 16 healthy volunteers were randomly divided into two groups, each receiving anterior teeth submucosal infiltration anesthesia and inferior alveolar nerve block anesthesia, respectively. The participants were injected with 0.9 mL, 1.8 mL, and 3.6 mL of 2% lidocaine HCl with 1∶100 000 epinephrine over three periods sequentially, followed by corresponding sequential injection of 0.2 mg, 0.4 mg, 0.8 mg of phentolamine mesylate at the same sites 30 min later.Blood samples were drawn from 5 min before injection to 15 h post the injection of phentolamine mesylate (16 time points). Adverse events were closely observed all the time. Plasma phentolamine mesylate was detected using UPLC-MS/MS with isotope as internal standard. WinNolin 6.1 software was used to calculate the pharmacokinetic parameters. RESULTS: Time to peak concerntration (Tmax) ranged from 12 to 13 min. Half-time of elimination (t1/2) ranged from 3.84 to 4.07 h, with a clearance (CL) of 190 L/h. Peak concentration (Cmax), area under concentration-time curves from 0 to t hour and from 0 to infinite time (AUC0-t and AUC0-∞) increased proportionally in the dose range of 0.2 mg to 0.8 mg. The results of confidence interval analysis showed nearly linear dynamic characteristics for the injection of phentolamine mesylate. All participants experienced mild adverse events, including pain at the injection point, dizziness, and palpitations. These adverse events disappeared without treatments. CONCLUSIONS: Phentolamine mesylate injection is effective for reversing oral local anesthetic effects.

11.
Small ; 13(16)2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28181404

RESUMO

BiFeO3 (BFO)-based ferroelectrics have been proved to be visible-light-driven photoelectrodes for O2 production. However, the hitherto reported photoelectrochemical performances remain inferior to meet the requirements for any applications. Besides, expensive noble metals (Ag, Au) are commonly required to achieve high photoelectric conversion efficiency. Here, the significant enhancements of photoelectrochemical performance is reported by fabricating a noble-metal-free reduced graphene oxide (RGO)/BFO composite film via a simple and cost-effective solution process. The optimized RGO/BFO composite film exhibits a 600% improvement of the short-circuit photocurrent density compared to that of the pristine BFO, and also outperforms the noble-metal/BFO cells under the same reaction conditions. Furthermore, the incident photon-to-current efficiency of the optimized RGO/BFO sample shows threefold enhancement. This study delivers a facile and low-cost approach to preparing 2D materials/ferroelectric heterostructures and offers a promising pathway to boost the performance of semiconducting ferroelectric photoelectrodes.

12.
Med Sci Monit ; 23: 5907-5915, 2017 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-29236682

RESUMO

BACKGROUND Percutaneous kyphoplasty (PKP) has been widely used to treat vertebral compression fractures (VCFs). Bilateral percutaneous punctures are always performed to access the fractured vertebrae. However, the procedure has expensive clinical costs, especially the cost for the device, which creates a heavy financial burden for patients. MATERIAL AND METHODS Data from 49 patients who have single-level non-neoplastic vertebral compression fracture (VCF) were collected for 12 months after treated by PKP, including 21 cases that used bilateral puncture with single balloon (S group) and 28 cases that used bilateral puncture with double balloon (D group). We assessed the clinical (visual analogue scale, VAS) and radiological (vertebral height and kyphotic angle, KA) outcomes. Cost data (gross medical cost, cost for the device and cost for drugs) were obtained from the medical bill of each patient. RESULTS Baseline patient variables were similar between the two groups except the compensation (S group

Assuntos
Fraturas por Compressão/cirurgia , Cifoplastia/métodos , Idoso , Povo Asiático , Cimentos Ósseos/uso terapêutico , China , Feminino , Humanos , Cifoplastia/economia , Cifose/cirurgia , Masculino , Pessoa de Meia-Idade , Medição da Dor , Fraturas da Coluna Vertebral/cirurgia , Traumatismos da Coluna Vertebral/cirurgia , Coluna Vertebral/cirurgia , Resultado do Tratamento , Vertebroplastia/métodos
13.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 47(1): 106-10, 2016 Jan.
Artigo em Zh | MEDLINE | ID: mdl-27062794

RESUMO

OBJECTIVE: To establish a high performance liquid chromatography-mass spectrometry/mass spectrometry (HPLC-MS/MS) method for determination of warfarin enantiomers in human plasma. METHODS: Warfarin enantiomers were extracted with ethyl acetate. The HPLC-MS/MS method used naproxen as internal standard, with methanol : water : formic acid = 85 : 15 : 0.05 as mobile phase, at a flow rate of 0.18 mL/min. R-warfain, S-warfarin and internal standard (IS) were separated on column MS Chiral MS-OD (50 x 2.1 mm, 3 µm). Warfarin enantiomers were protonated with electroapry ionization (ESI) in negative electron ionization mode. The ion pairs being detected were (m/z) 307.2-160.9 (R-warfain and S-warafrin) and (m/z) 228.9 --> 185.1 (IS). RESULTS: The within-run precision relative standard deviations (RSD) and between-run precision RSD of R-warfarin were 3.2%-5.8% and 2.5%-5.1%, respectively. The method recoveries and extraction recoveries of R-warfarin were (96.1 ± 5. 6)%-(105.4 ± 4.7)% and 80.7%-84.4%, respectively. The matrix effect RSD was less than 10%. The within-run precision RSD and between-run precision RSD of S-warfarin were 3.7%-5.2% and 3.2%-4.8%, respectively. The method recoveries and extraction recoveries of 5-warfarin were (98.3 ± 5.1)%-(103.7 ± 3.8)% and 81.3%-84.6%, respectively. The limit of quantification was 0.1 µg/mL for both analytes. CONCLUSION: This new method is fully validated with satisfactory accuracy and adequate reproducibility. Therefore, it can be applied for separating and detecting plasma warfarin enantiomers.


Assuntos
Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem , Varfarina/sangue , Humanos , Reprodutibilidade dos Testes , Estereoisomerismo
14.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 47(1): 85-9, 92, 2016 Jan.
Artigo em Zh | MEDLINE | ID: mdl-27062789

RESUMO

OBJECTIVE: To evaluate bioequivalence of two specifications of ubenimex capsules in comparison with the Japanese branded product (R). METHODS: The study adopted a 3-way crossover design in twenty-four healthy male volunteers, whose plasma concentrations of ubenimex were determined by UPLC-MS/MS after administration a single oral dose of 30 mg of domestic ubenimex T1 (10 mg/capsule), T2 (30 mg/capsule) and branded ubenimex R (30 mg/capsule) sequentially. The bioequivalence was evaluated using WinNonlin6. 1 statistical analysis software. RESULTS: One volunteer was excluded because of failure to follow medication instructions. The main pharmacokinetic parameters of ubenimex of T1, T2 and R were as follows: C(max) (2 646.73 ± 454.09) ng/mL, (2 675.91 ± 474.32) ng/mL and (2 432.79 ± 544.32) ng/mL, respectively; T(max) (0.68 ± 0.23) h, (0.76 ± 0.19) h and (0.77 ± 0.26) h, respectively; AUC(0-t) (3 925.23 ± 478.34)(ng x h)/mL, (3 804.62 ± 448.84)(ng x h)/mL and (3 789.30 ± 443.15)(ng x h)/mL, respectively; AUC(0-∞)(3 938.31 ± 479.54)(ng x h)/mL, (3 817.26 ± 450.90) (ng x h)/mL and (3 800.90 ± 444.77) (ng x h)/mL, respectively; CL/F (7.72 ± 0.92) L/h, (7.97 ± 0.98) L/h and (7.99 ± 0.90) L/h, respectively; Vd (26.08 ± 9.20 )L, (25.65 ± 10.22) L and (26.03 ± 10.05) L, respectively. The relative bioavailability F(0-t) and F(0-∞) of T1 and T2 against the branded preparation R were (103.90 ± 9.19)% and (100.77± 9.36)%, and (103.93 ± 9.20)% and (100.79 ± 9.33)%, respectively. CONCLUSION: Both ubenimex capsules T1 and T2 are bioequivalent to the Japanese branded products.


Assuntos
Leucina/análogos & derivados , Equivalência Terapêutica , Disponibilidade Biológica , Cápsulas , Estudos Cross-Over , Voluntários Saudáveis , Humanos , Leucina/administração & dosagem , Leucina/sangue , Masculino , Espectrometria de Massas em Tandem
15.
J Sep Sci ; 37(20): 2947-54, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25082716

RESUMO

A high-throughput, rapid, and efficient modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) method with a simple cleanup procedure has been developed for simultaneously determining 227 pesticides in pepper samples by liquid chromatography with tandem mass spectrometry (running time: 10 min). Pesticide residues were extracted/partitioned with an acetonitrile/DisQuE QuEChERS pouch, and the resulting samples were cleaned up with different methods: dispersive solid-phase extraction with primary secondary amines or multiwalled carbon nanotubes and graphitized carbon solid mini cartridge column. The results indicated that multiwalled carbon nanotubes dispersive sorbents achieved the best recoveries and had less matrix interference. The numbers of pesticides with a recovery in the range of 70-120% were 199 at a spiked level of 40 µg/kg. The correlation coefficients (r(2)) for 227 pesticides were above 0.99, while the limits of quantitation of pesticides in pepper samples ranged from 0.13 to 13.51 µg/kg (S/N = 10), and the limits of detection ranged from 0.04 to 4.05 µg/kg (S/N = 3). The relative standard deviations of approximately 197 pesticides were below 20% at spiked levels of 40 µg/kg. Based on these results, the proposed method was chosen as the most suitable cleanup procedure for the determination of multiresidue pesticides in pepper samples.


Assuntos
Capsicum/química , Cromatografia Líquida/métodos , Resíduos de Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Resíduos de Praguicidas/classificação , Padrões de Referência , Reprodutibilidade dos Testes
16.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 45(3): 497-501, 2014 May.
Artigo em Zh | MEDLINE | ID: mdl-24941827

RESUMO

OBJECTIVE: To develop a sensitive and reproducible HPLC-MS/MS method for analyzing dimemorfan in human plasma and urine. METHODS: Dimemorfan was extracted from plasma and urine by redistilled ether, with lidocaine serving as the internal standard (IS). The analysis was performed on a column of ultimate C18 (50 mm x 4.6 mm, 5 microm) with the mobile phase consisting of methyl alcohol-water-formic acid = 75:25 : 0.05 at a flow rate of 0. 2 mL/min. Dimemorfan was detected by API 3000 mass spectrometer, with multiple reaction monitoring after protonated with ESI in positive electron ionization mode. The ion pairs being detected were (m/z) 256.4-->155. 3 (dimemorfan) and 235.4-->86.1 (lidocaine), respectively. RESULTS: The regression equation for dimemorfan showed excellent linearity (r = 0.995 7) from 0. 025 to 5.0 ng/mL of plasma with detecting limitation of 0.025 ng/mL and perfect linearity (r = 0.9983) from 0.1 to 20.0 ng/mL of urine with detecting limitation of 0.1 ng/mL. The method recoveries of dimemorfan in plasma and urine were ranging from 103.38% to 106.88% and 90.05% to 101.40%, respectively. The maximum intra-day and inter-day relative standard deviations (RSD) of concentration of dimemorfan were 5.92% and 5. 70% (for plasma), 10.35% and 8.80% (for urine), respectively. CONCLUSION: This new method was validated to be accurate and sensitive to determinate the concentration of dimemorfan in plasma and urine samples, and can be applied for pharmacokinetic studies of dimemorfan.


Assuntos
Cromatografia Líquida de Alta Pressão , Morfinanos/sangue , Morfinanos/urina , Espectrometria de Massas em Tandem , Humanos
17.
RSC Adv ; 14(23): 16411-16420, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38774619

RESUMO

In this work, an attapulgite-graphene nanocomposite was prepared. The tribological properties of the prepared attapulgite-graphene nanocomposite as an additive for 200SN mineral lubricating oil were investigated using an SRV-IV tribometer through ball-on-disk contact mode for the first time. The characterization of the prepared nanocomposite indicated that attapulgite nanofibers are enveloped by the graphene nanosheets and present fine combination. The tribological test results show that the friction-reducing and antiwear properties of 200SN were obviously improved by adding the attapulgite-graphene nanocomposite. Through the characterization and analysis of the worn surface and cross-section, it was found that a tribofilm composed of Fe, Fe3O4, FeO, Fe2O3, FeOOH, graphite, graphene, SiO2 and organic compounds was formed on the worn surface. Furthermore, the bonding between the tribofilm and steel matrix is tight. The tribofilm and lubricating oil achieve a solid-liquid coupling lubrication effect, which is responsible for the improvement of the friction-reducing and antiwear properties.

18.
ACS Appl Mater Interfaces ; 16(30): 40222-40230, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39028921

RESUMO

We present a novel and stable laminated structure to enhance the performance and stability of silicon (Si) photocathode devices for photoelectrochemical (PEC) water splitting. First, by utilizing Cu nanoparticle catalysts to work on a n+p-black Si substrate via the metal-assisted chemical etching, we can achieve the black silicon with a porous pyramid structure. The low depth holes on the surface of the pyramid caused by Cu etching not only help enhance the light capture capability with quite low surface reflectivity (<5%) but also efficiently protect the p-n junction from damage. To improve the charge migration efficiency and mitigate parasitic light absorption from cocatalysts at the same time, we drop casted quantum dots (QDs) MoS2 with the size of nanometer scale as the first layer of catalyst. Hence, we then can safely electrodeposit cocatalyst Co nanoparticles to further enhance interface transfer efficiency. The synergistic effects of cocatalysts and optimized light absorption from the morphology and QDs contributed to the overall enhancement of PEC performance, offering a promising pathway for an efficient, low cost, and stable (over 100 h) hydrogen production photocathode.

19.
J Ethnopharmacol ; 324: 117745, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38228231

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Jin-Gui-Shen-Qi Wan (JGSQW) is a traditional Chinese medicine formula that has been traditionally used to alleviate urinary system ailments such as frequent urination and polyuria. Clinical studies have indicated that when combined with hypoglycaemic drugs, JGSQW exhibits a synergistic effect and can improve diabetic nephropathy (DN), yet its underlying mechanism and targets remain unclear. AIM OF THE STUDY: This study aims to investigate the therapeutic efficacy of JGSQW and its underlying mechanisms using a DN db/db mouse model. MATERIALS AND METHODS: Ultrahigh-performance liquid chromatography coupled with mass spectrometry was utilized to analyse the primary active compounds, blood levels, and pharmacokinetics of JGSQW. Additionally, the therapeutic effects of JGSQW and metformin on blood glucose levels, lipid levels, renal function, and renal pathology in diabetic nephropathy mice were investigated using a db/db mouse model. Proteomic analysis was carried out to identify the primary target of JGSQW in treating DN. The mechanism of action was verified by western blotting, immunohistochemistry, and immunofluorescence. Then, molecular docking and molecular dynamics, transfection, drug affinity responsive target stability (DARTS) assay and cell thermal migration assay (CETSA) further validated the targeted binding effect. RESULTS: JGSQW combined with metformin significantly improved the blood glucose levels, blood lipids, renal function, and renal pathology of DN mice. JGSQW mainly exerted its therapeutic effect on DN by targeting major histocompatibility complex class II (MHC class II) molecules. Immunohistochemistry results showed that JGSQW inhibited the expression of collagen I, fibronectin, and alpha smooth muscle actin (α-SMA) expression. Immunofluorescence and Western blot results showed that JGSQW inhibited the expression of H2-Ab1 and H2-Aa, which are MHC class II molecules, thereby suppressing CD4+ T-cell infiltration and improving diabetic kidney fibrosis. The binding ability of paeoniflorin to H2-Aa was predicted and verified by molecular, DARTS, and CETSA assays. Treatment with 80 µM paeoniflorin effectively alleviated high glucose-induced injury in the MPC-5 injury model. H2-Aa was overexpressed at this model concentration, and Western blotting further confirmed that paeoniflorin reduced glomerular podocyte fibrosis by regulating H2-Aa. CONCLUSIONS: JGSQW combined with metformin may have a synergistic effect to alleviates renal fibrosis in diabetic nephropathy by downregulating immune complex MHC class II molecules and attenuating the antigen presentation effect of MHC class II on CD4.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Glucosídeos , Metformina , Monoterpenos , Camundongos , Animais , Nefropatias Diabéticas/patologia , Glicemia , Simulação de Acoplamento Molecular , Proteômica , Transdução de Sinais , Fibrose , Antígenos de Histocompatibilidade Classe II/farmacologia , Antígenos de Histocompatibilidade Classe II/uso terapêutico , Metformina/farmacologia , Metformina/uso terapêutico
20.
Bioanalysis ; : 1-14, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39115055

RESUMO

Aim: We aimed to establish a sensitive LC-MS/MS method to analyze the pharmacokinetics of Ani HBr tablets and injection. Methods: Around 10 mmNH4Ac containing 0.1% formic acid and acetonitrile were used as the mobile phase. Acute lung injury in septic and normal rats, respectively, were administered Ani HBr tablets at doses of 12.5, 25 and 50 mg/kg and injection at doses of 4, 8 and 16 mg/kg, followed by extraction of the drugs from plasma using ethyl acetate for subsequent analysis. Results & conclusion: The method met the requirements for biological analysis. Ani HBr tablets absorbed slowly in rats with disease, tail vein administration was a more promising approach for treating septic acute lung injury.


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