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1.
J Hazard Mater ; 421: 126704, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34325292

RESUMO

Cadmium (Cd) is a toxic environmental pollutant and induces toxic effects to organism. Nevertheless, the mechanism of Cd-induced toxicity in swine remains obscure. To explore this, 10 healthy 6-week-old weaned swine were placed into two groups stochastically, the Cd group was treated with a commercial diet containing 20 mg/kg Cd for 40 days. The results of histopathological and ultrastructural observations showed typical necrosis features and inflammatory cell infiltration in Cd group. Excessive Cd suppressed T-AOC and SOD activities, increased MDA content and ROS levels. Cd diet elevated the expression of RIPK1, RIPK3, and MLKL to activate the RIPK3-dependent necroptosis pathway. Results of Th1 and Th2 cytokines indicated that the levels of IL-4, IL-6 and IL10 was increased, while the level of IFN-γ was decreased, illustrating Th1/Th2 immune imbalance leads to aggravate inflammatory responses. Cd activated the TNF-α/NF-κB pathway and induced inflammatory responses via increasing the expression of HO-1, IL-1ß, iNOS, COX2. Heat shock proteins were notably elevated in response to inflammatory reactions. And these effects were inhibited by necrostatin-1 (Nec-1) and N-acetyl-cysteine (NAC). Altogether, these data demonstrated that Cd induced necroptosis and inflammation to aggravate small intestine injury in swine by increasing the excessive accumulation of ROS and imbalanced Th1/Th2, respectively.


Assuntos
NF-kappa B , Necroptose , Animais , Cádmio/toxicidade , Inflamação/induzido quimicamente , Intestino Delgado/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Estresse Oxidativo , Suínos , Fator de Necrose Tumoral alfa
2.
Chem Commun (Camb) ; 57(95): 12764-12767, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34730142

RESUMO

Here, we report an improved tandem catalytic mechanism for electroreduction of CO2 to C2H4. Cu(111) nanoparticles with an average size of 5.5 ± 0.9 nm were anchored on a conductive Cu-based metal-organic framework (Cu-THQ) by in situ electrochemical synthesis. Compared to Cu(111) nanoparticles, the C2H4 faradaic efficiency of the tandem catalyst Cu(111)@Cu-THQ was increased doubly.

4.
Hepatobiliary Surg Nutr ; 10(5): 631-645, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34760967

RESUMO

Background: To compare the treatment effectiveness and safety among transarterial infusion chemotherapy (TAI) with FOLFOX regimen, transarterial chemoembolization (TACE), and sorafenib in patients with BCLC stage C hepatocellular carcinoma (HCC). Methods: The data of consecutive patients with BCLC stage C HCC treated with TAI, TACE, or sorafenib from January 2015 to December 2018 at three centers were retrospectively analyzed. Propensity-score matched (PSM) analysis was pairwise performed to reduce selection bias. Treatment effectiveness and safety were evaluated and compared using the Kaplan-Meier method, log-rank test, Cox regression models, and χ2 test. Results: The median overall survival (OS) in the matched TAI cohort was significantly longer than the sorafenib cohort (19.6 vs. 7.5 months, P=0.009), and the TACE cohort (estimated 27.8 vs. 6.6 months, P<0.001). The difference in median progression-free survival (PFS) between the matched TAI and sorafenib cohorts was not significant (5.8 vs. 2.3 months, P=0.219). The median PFS in the matched TAI cohort was significantly longer than the TACE cohort (6.5 vs. 2.8 months, P<0.001). The objective response rate (ORR) in the matched TAI cohort was significantly higher than the sorafenib cohort (36.4% vs. 0.0%, P<0.001) and the TACE cohort (48.7% vs. 4.7%, P<0.001). The incidences of adverse events (AEs) were similar among these three cohorts. Conclusions: TAI with FOLFOX regimen was an effective and safe therapy that improved survival of patients with BCLC stage C HCC.

5.
Liver Cancer ; 10(5): 500-509, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34721511

RESUMO

Introduction: In a multicenter, open-label, parallel-group, randomized, phase 2 study for pretreated advanced hepatocellular carcinoma (HCC), camrelizumab showed potent antitumor activity and acceptable safety profile. The aim of this report was to provide long-term data and evaluate potential benefit of treatment with camrelizumab beyond progression. Methods: From November 15, 2016, to November 16, 2017, 217 patients received camrelizumab 3 mg/kg intravenously every 2 or 3 weeks. Treatment beyond first Response Evaluation Criteria in Solid Tumors (RECIST)-defined progression (TBP) with camrelizumab was allowed. Results: At data cutoff of December 16, 2019 (>2 years after the last patient enrollment; median duration of follow-up, 13.2 months [IQR 5.7-25.8]), 14 (43.8%) of the 32 responses per blinded independent central review were ongoing. The median duration of response was not reached (range 2.5-30.5 + months). The ongoing response rates at 12, 18, and 24 months were 68.3% (95% confidence interval [CI] 47.7-82.2), 59.8% (95% CI 38.8-75.6), and 53.1% (95% CI 31.0-71.0), respectively. The median overall survival (OS) was 14.2 months (95% CI 11.5-16.3). The 18- and 24-month OS rates were 41.3% (95% CI 34.6-47.9) and 33.7% (95% CI 27.3-40.2), respectively. Of the 172 patients who experienced RECIST-defined progression per investigator, 102 received TBP, while 70 did not (non-TBP). The median OS was 16.9 months (95% CI 13.3-22.6) in the TBP group versus 9.4 months (95% CI 5.8-14.8) in the non-TBP group, and the 18- and 24-month OS rates were 47.5% (95% CI 37.3-56.9) versus 33.1% (95% CI 22.3-44.3) and 38.8% (95% CI 29.2-48.4) versus 23.2% (95% CI 13.8-34.1), respectively. No new safety signals of camrelizumab were observed. Conclusions: With prolonged follow-up, camrelizumab continues to demonstrate the durable response and long survival in pretreated advanced HCC patients with manageable toxicities, especially in those who continued the treatment beyond first RECIST-defined progression.

6.
Artigo em Inglês | MEDLINE | ID: mdl-34653302

RESUMO

Switching materials in channels of nonlinear optics (NLOs) are of particular interest in NLO material science. Numerous crystalline NLO switches based on structural phase transition have emerged, but most of them reveal a single-step switch between two different second-harmonic-generation (SHG) states, and only very rare cases involve three or more SHG states. Herein, we report a new organic-inorganic hybrid salt, (Me3 NNH2 )2 [CdI4 ], which is an unprecedented case of a reversible three-step NLO switch between SHG-silent, -medium, -low, and -high states, with high contrasts of 25.5/4.3/9.2 in a temperature range of 213-303 K. By using the combined techniques of variable-temperature X-ray single-crystal structural analyses, dielectric constants, solid-state 13 C nuclear magnetic resonance spectroscopy, and Hirshfeld surface analyses, we disclose that this four-state switchable SHG behavior is highly associated with the stepwise-changed molecular dynamics of the polar organic cations. This finding demonstrates well the complexity of molecular dynamics in simple hybrid salts and their potential in designing new advanced multistep switching materials.

7.
J Am Chem Soc ; 143(42): 17424-17430, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34637290

RESUMO

Reducing CO2 into fuels via photochemical reactions relies on highly efficient photocatalytic systems. Herein, we report a new and efficient photocatalytic system for CO2 reduction. Driven by electrostatic attraction, an anionic metal-organic framework Cu-HHTP (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene) as host and a cationic photosensitizer [Ru(phen)3]2+ (phen = 1,10-phenanthroline) as guest were self-assembled into a photocatalytic system Ru@Cu-HHTP, which showed high activity for photocatalytic CO2 reduction under laboratory light source (CO production rate of 130(5) mmol g-1 h-1, selectivity of 92.9%) or natural sunlight (CO production rate of 69.5 mmol g-1 h-1, selectivity of 91.3%), representing the remarkable photocatalytic CO2 reduction performance. More importantly, the photosensitizer [Ru(phen)3]2+ in Ru@Cu-HHTP is only about 1/500 in quantity reported in the literature. Theoretical calculations and control experiments suggested that the assembly of the catalysts and photosensitizers via electrostatic attraction interactions can provide a better charge transfer efficiency, resulting in high performance for photocatalytic CO2 reduction.

8.
Open Med (Wars) ; 16(1): 1482-1485, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34703900

RESUMO

Trauma-induced complete lead fracture is a rare complication of pacemaker implantation. Only a few cases have been previously reported. Common treatment included replacement of pacemaker and/or extraction of fractured lead. In this report, however, we describe this unique case of complete traumatic pacemaker lead fracture. The patient had her right-ventricular lead fractured after a bicycle accident and had lived with the fractured lead for 8 months prior to her hospitalization. After examinations, she was treated with a relatively conservative strategy. The pacemaker and fractured lead were left for further observation and follow-up.

9.
Front Pharmacol ; 12: 753599, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34658894

RESUMO

Achyranthes bidentata Blume, a traditional Chinese medicine, is widely acknowledged for its function of invigorating the liver and kidneys and as a stranguria-relieving diuretic and used in the treatment of edema, gonorrhea, and other diseases. Polysaccharide (ABPS), isolated from Achyranthes bidentata Blume, has been demonstrated to have multiple biological activities including immunomodulatory effects. However, the mechanisms underlying the effects of ABPS have not been fully investigated. The present study is conducted to explore the underlying mechanism of immunomodulatory activities of ABPS. Results showed that ABPS significantly increased the secretion of IL-1ß and TNF-α in J744 A.1 cells. Nitric oxide (NO) also significantly increased after ABPS treatment. The special antibodies (Toll-like receptor 4 (TLR4) antibody and CD14/TLR4 antibody) significantly decreased the activation, while the Toll-like receptor 2 (TLR2) antibody could not abolish this activation. Meanwhile, pyrrolidine dithiocarbamate (PDTC), a specific inhibitor of NF-κB, remarkably inhibited the secretion of IL-1ß and TNF-α induced by ABPS in J744 A.1 cells. Western blotting (WB) and confocal laser scanning microscopy (CLSM) showed that ABPS promoted NF-κB translocation into the nucleus. Furthermore, the mRNA and protein expression of TLR4 and MyD88 were significantly increased after ABPS treatment. Taken together, these findings suggested that the immunomodulatory mechanism of ABPS was associated with the secretion of cytokines by stimulating the NF-κB pathway through TLR4/MyD88 signaling.

10.
BMC Ophthalmol ; 21(1): 343, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34551740

RESUMO

BACKGROUND: Existing evidence suggests that visual field defect in eyes with glaucoma significantly varies between individuals. The following study compared the central visual field defects with the peripheral visual field defects in patients with suspect glaucoma and primary open-angle glaucoma (POAG) and investigated whether using the central visual field test alone could result in loss of clinically valuable information. METHODS: In this prospective observational study, 167 eyes from 89 patients with suspect glaucoma or POAG were first examined with static automated perimetry (SAP), followed by a peripheral visual field test on Octopus 900 perimeter (Haag-Streit, Koeniz, Switzerland). The peripheral visual field test was performed by "Auto Kinetic Perimetry" program, in which Goldmann III4e stimuli randomly moved along 16 vectors at a constant angular velocity of 5 deg/s. RESULTS: Glaucomatous peripheral visual field defects were seen in 18% of the eyes with a normal central visual field. In addition, 86% of glaucoma patients with moderate-to-severe central visual field defects had corresponding peripheral visual field defects in the form of localized or diffuse depression of the isopters. Furthermore, a moderate correlation was found between the central and peripheral visual fields. The median test duration was 71 s for the peripheral test and 803 s for the central test (p < 0.001). CONCLUSIONS: Our study demonstrated the diversity of glaucomatous visual field defects, as well as the possibility of losing the clinically valuable information due to focusing on the central visual field test alone. The peripheral kinetic perimetry is clinically feasible to complement the central static perimetry for a comprehensive assessment of visual function in glaucoma patients.


Assuntos
Glaucoma de Ângulo Aberto , Glaucoma , Glaucoma de Ângulo Aberto/diagnóstico , Humanos , Transtornos da Visão/diagnóstico , Testes de Campo Visual , Campos Visuais
12.
Biomark Med ; 15(14): 1277-1288, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34486883

RESUMO

Aim: The potential of long noncoding RNA in hepatocellular carcinoma (HCC) has led to promising insights into therapeutic intervention. The clinical significance of LINC02518 in HCC is unclear. This study aimed to evaluate the predictive value of a novel long noncoding RNA, LINC02518, for the prognosis of patients with HCC. Methods: Between December 2005 and November 2011, 125 and 75 HCC patients in the training and validation groups, respectively, who underwent liver surgery were included in our study. The LINC02518 expression of HCC and corresponding nontumor liver tissues was detected using microarray and reverse transcription quantitative polymerase chain reaction (RT-qPCR). These HCC patients were assigned into high and low LINC02518 expression groups based on the threshold of the receiver operating characteristic curve. Kaplan-Meier analysis was performed to determine the prognosis of HCC patients. Results: LINC02518 expression was upregulated in paired tumor samples compared with corresponding nontumor samples in the two groups. The area under the receiver operating characteristic curve for the levels of LINC02518 in the diagnosis of HCC was 0.66, 95% CI: 0.59-0.73. HCC patients with high LINC02518 expression had significantly worse tumor recurrence-free, metastasis-free, disease-free and overall survival than those with low LINC02518 expression. Conclusion: LINC02518 is negatively correlated with the prognosis of HCC and provides a promising strategy for the treatment and prognosis of HCC.

13.
Biofactors ; 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34570919

RESUMO

Trimethyltin chloride (TMT) is a stabilizer for polyvinyl chloride plastics that causes serious health hazards in nontarget organisms. Melatonin (MT) exhibits powerful protective effects in cardiac diseases. As a new environmental pollutant, TMT-induced cardiotoxicity and the protective effects of MT remain unclear. To explore this, the mice were treated with TMT (2.8 mg/kg) and/or MT (10 mg/kg) for 7 days. Firstly, the histopathological and ultrastructural evaluation showed that TMT induced cardiac damage, tumescent rupture and nuclear pyknosis. Moreover, TMT elevated the expressions of pyroptosis genes NLRP3, ASC and Cas1 and inflammation factors IL-6, IL-17 and TNFα. Secondly, TMT reduced antioxidant enzymes (GSH, CAT and T-AOC) via decreasing the expression of genes associated with the Keap1-Nrf2/ARE pathway to increase oxidative stress. Thirdly, TMT decreased the expression of genes associated with the ARE-driven drug metabolizing enzymes (DMEs), including Akr7a3, Akr1b8, and Akr1b10. Besides, TMT upregulated the mRNA expression of nuclear Xenobiotic metabolism on cytochrome P450s enzymes via increasing the expression of CAR, PXP, and AHR genes. Furthermore, MT treatment mitigated the aforementioned adverse changes induced by TMT. Overall, these results demonstrated that TMT caused pyroptosis and inflammation to aggravate cardiac damage via inducing excessive oxidative stress, imbalance of DMEs homeostasis, and nuclear Xenobiotic metabolism disorder, which could be alleviated by MT.

14.
Biol Trace Elem Res ; 2021 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-34365572

RESUMO

Cadmium (Cd), a toxic heavy metal, exists widely in the environment, which can enter organisms through a variety of ways and cause damage to various organs and tissues. However, the mechanism of lung toxicity in swine after Cd exposure is still unclear. To explore the molecular mechanism of swine lung damage caused by Cd exposure, we established the model of Cd exposure, and Cd chloride (20 mg/kg CdCl2) was added to the diet of swine for continuous exposure for 40 days. TUNEL staining showed that the apoptosis of swine lung increased significantly after Cd exposure. Meanwhile, the results of qRT-PCR showed that Cd induced oxidative stress and inhibited the expression of antioxidant enzymes including CAT, GCLM, GST, SOD, and GSH-px in lung tissue. Cd exposure activated mitochondrial apoptosis pathway via the TRAF2/ASK1/JNK signaling pathway. In brief, we considered that Cd exposure causes oxidative stress in lung and induces lung cell apoptosis through the TRAF2/ASK1/JNK pathway and increases the expression of HSPs to resist the toxicity of Cd. Our research enriches the theoretical basis of Cd toxicity and provides reference for comparative medicine.

15.
Artigo em Inglês | MEDLINE | ID: mdl-34453221

RESUMO

PURPOSE: The aim of this retrospective study was to compare the clinical outcomes of pembrolizumab-lenvatinib-transarterial chemoembolization (TACE) versus lenvatinib-TACE sequential therapy in selected populations of Chinese patients with initially unresectable hepatocellular carcinoma (uHCC) harbouring programmed cell death ligand-1 (PD-L1) expression. METHODS: Consecutive patients with initial PD-L1-positive uHCC who received pembrolizumab-lenvatinib-TACE or lenvatinib-TACE sequential therapy were retrospectively identified from three medical institutions during 2016-2020. The primary endpoints included the rate of conversion therapy, defined as converting initially uHCC to hepatectomy, overall survival (OS), and progression-free survival (PFS); secondary endpoint was the frequency of key adverse events (AEs). RESULTS: In total, 220 consecutively recruited patients were retrospectively reviewed, 78 of whom were ineligible according to the current criteria, leaving 142 patients [pembrolizumab-lenvatinib-TACE: n = 70, median age 58 years (range 36-69) and lenvatinib-TACE: n = 72, 57 years (35-68)] who were eligible for the study. The median duration of follow-up was 27 months [95% confidence interval (CI), 26.3-28.7 months]. At the last follow-up, the rate of conversion therapy was 25.7% in the pembrolizumab-lenvatinib-TACE group and 11.1% in the lenvatinib-TACE group (p = 0.025). The median OS was 18.1 months (95% CI 16.5-20.7) in the pembrolizumab-lenvatinib-TACE group versus 14.1 months (95% CI 12.2-16.9) in the lenvatinib-TACE group [hazard ratio (HR) 0.56, 95% CI 0.38-0.83; p = 0.004]. A distinct difference in the median PFS interval between the groups was detected [9.2 months (95% CI 7.1-10.4) in the pembrolizumab-lenvatinib-TACE group vs. 5.5 months (95% CI 3.9-6.6) in the lenvatinib-TACE group (HR 0.60; 95% CI 0.39-0.91; p = 0.006)]. The rates of the key AEs assessed, which were hypertension, nausea, and rash, were higher in the pembrolizumab-lenvatinib-TACE group than in the lenvatinib-TACE group (all p < 0.05). CONCLUSION: Among the selected populations of patients with initial PD-L1-positive uHCC, pembrolizumab-lenvatinib-TACE sequential therapy may have promising antitumour activity, with an acceptable conversion rate and a well-characterized safety profile.

16.
J Proteome Res ; 20(9): 4346-4356, 2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34342461

RESUMO

Lung cancer (LC) is a widespread cancer that is the cause of the highest mortality rate accounting for 25% of all cancer deaths. To date, most LC patients are diagnosed at the advanced stage owing to the lack of obvious symptoms in the early stage and the limitations of current clinical diagnostic techniques. Therefore, developing a high throughput technique for early screening is of great importance. In this work, we established an effective and rapid salivary metabolic analysis platform for early LC diagnosis and combined metabolomics and transcriptomics to reveal the metabolic fluctuations correlated to LC. Saliva samples were collected from a total of 150 volunteers including 89 patients with early LC, 11 patients with advanced LC, and 50 healthy controls. The metabolic profiling of noninvasive samples was investigated on an ultralow noise TELDI-MS platform. In addition, data normalization methods were screened and assessed to overcome the MS signal variation caused by individual difference for biomarker mining. For untargeted metabolic profiling of saliva samples, around 264 peaks could be reliably detected in each sample. After multivariate analysis, 23 metabolites were sorted out and verified to be related to the dysfunction of the amino acid and nucleotide metabolism in early LC. Notably, transcriptomic data from online TCGA repository were utilized to support findings from the salivary metabolomics experiment, including the disorder of amino acid biosynthesis and amino acid metabolism. Based on the verified differential metabolites, early LC patients could be clearly distinguished from healthy controls with a sensitivity of 97.2% and a specificity of 92%. The ultralow noise TELDI-MS platform displayed satisfactory ability to explore salivary metabolite information and discover potential biomarkers that may help develop a noninvasive screening tool for early LC.


Assuntos
Neoplasias Pulmonares , Saliva , Humanos , Lasers , Neoplasias Pulmonares/diagnóstico , Espectrometria de Massas , Metabolômica
17.
Electrophoresis ; 42(21-22): 2264-2272, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34278592

RESUMO

Biological cells in vivo typically reside in a dynamic flowing microenvironment with extensive biomechanical and biochemical cues varying in time and space. These dynamic biomechanical and biochemical signals together act to regulate cellular behaviors and functions. Microfluidic technology is an important experimental platform for mimicking extracellular flowing microenvironment in vitro. However, most existing microfluidic chips for generating dynamic shear stress and biochemical signals require expensive, large peripheral pumps and external control systems, unsuitable for being placed inside cell incubators to conduct cell biology experiments. This study has developed a microfluidic generator of dynamic shear stress and biochemical signals based on autonomously oscillatory flow. Further, based on the lumped-parameter and distributed-parameter models of multiscale fluid dynamics, the oscillatory flow field and the concentration field of biochemical factors has been simulated at the cell culture region within the designed microfluidic chip. Using the constructed experimental system, the feasibility of the designed microfluidic chip has been validated by simulating biochemical factors with red dye. The simulation results demonstrate that dynamic shear stress and biochemical signals with adjustable period and amplitude can be generated at the cell culture chamber within the microfluidic chip. The amplitudes of dynamic shear stress and biochemical signals is proportional to the pressure difference and inversely proportional to the flow resistance, while their periods are correlated positively with the flow capacity and the flow resistance. The experimental results reveal the feasibility of the designed microfluidic chip. Conclusively, the proposed microfluidic generator based on autonomously oscillatory flow can generate dynamic shear stress and biochemical signals without peripheral pumps and external control systems. In addition to reducing the experimental cost, due to the tiny volume, it is beneficial to be integrated into cell incubators for cell biology experiments. Thus, the proposed microfluidic chip provides a novel experimental platform for cell biology investigations.

18.
Anal Chem ; 93(29): 10220-10228, 2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34261311

RESUMO

Isolation of microalgal cells is as an indispensable part of producing biofuels for energy security and detecting toxic contaminants for marine routine monitoring. Microalgae live together with various microalgae naturally, and abundant samples need to be tackled in practical applications. Therefore, effective separation technologies need to be developed urgently to achieve high-throughput separation of various microalgae. Herein, we develop a reliable device to characterize the dielectric response of microalgae and sequentially separate various microalgae utilizing dielectrophoretic force in a bipolar electrode (BPE) arrayed device. First, by investigating the array width extension (AWE) effect on the electric- and flow-field distributions, we explore consequences of incidental electrohydrodynamic mechanisms and axial flow rate on the separation. Second, based on device performance on sample characterizations, we demonstrate this technology by separating microparticles in three- and five-channel devices. Third, we discriminate dead and live cells to explore its capability using the cell viability test and illustrate the AWE influence on the separation. Fourth, we characterize dielectric responses of different microalgae and separate C. vulgaris and Oocystis sp. Finally, we extended BPEs in length and developed an arrayed device for sequential separation of various microalgae, and this platform is successfully engineered in high-throughput isolation of C. vulgaris from complex samples. This technology presents good potential in addressing depleting fossil fuel and burgeoning environmental concerns due to its performance in the separation of microalgal strains from complex samples.


Assuntos
Clorófitas , Microalgas , Separação Celular , Eletrodos
19.
J Proteome Res ; 20(8): 4022-4030, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34279957

RESUMO

More and more evidence has proved that urinary metabolites can instantly reflect disease state. Therefore, ultra-sensitive and reproducible detection of urinary metabolites in a high-throughput way is urgently desirable for clinical diagnosis. Matrix-free laser desorption/ionization mass spectrometry (LDI-MS) is a high-throughput platform for metabolites detection, but it is encountered by severe interference from numerous salts in urine samples, because the crystallized urine salt on dried samples could result in poor reproducibility in LDI-MS detection. The present work proposed a tip-contact extraction (TCE) technique to eliminate interference from the urine salt. Vertical silicon nanowire arrays decorated with the fluorinated ethylene propylene film (FEP@VSiNWs) could effectively extract metabolites from the urine sample dropping on its surface. High salt tolerance was observed in the subsequent LDI-MS detection of the metabolites extracted on the tip of FEP@VSiNWs even in the presence of 1 M urea. Stable and reproducible mass spectra for non-target metabolic analysis were obtained in real urine samples with different dilution folds. Urinary metabolites collected from bladder cancer (BC) patients were reliably profiled by the TCE method coupled with negative LDI-MS. Based on this platform, potential metabolic biomarkers that can distinguish BC patients and normal controls were uncovered.


Assuntos
Lasers , Silício , Humanos , Espectrometria de Massas , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
20.
Molecules ; 26(11)2021 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-34204150

RESUMO

The purpose of this study was to develop mixed polymeric micelles with high drug loading capacity to improve the oral bioavailability of icaritin with Soluplus® and Poloxamer 407 using a creative acid-base shift (ABS) method, which exhibits the advantages of exclusion of organic solvents, high drug loading and ease of scaling-up. The feasibility of the ABS method was successfully demonstrated by studies of icaritin-loaded polymeric micelles (IPMs). The prepared IPMs were characterized to have a spherical shape with a size of 72.74 ± 0.51 nm, and 13.18% drug loading content. In vitro release tests confirmed the faster release of icaritin from IPMs compared to an oil suspension. Furthermore, bioavailability of icaritin in IPMs in beagle dogs displayed a 14.9-fold increase when compared with the oil suspension. Transcellular transport studies of IPMs across Caco-2 cell monolayers confirmed that the IPMs were endocytosed in their intact forms through macropinocytosis, clathrin-, and caveolae-mediated pathways. In conclusion, the results suggested that the mixed micelles of Soluplus® and Poloxamer 407 could be a feasible drug delivery system to enhance oral bioavailability of icaritin, and the ABS method might be a promising technology for the preparation of polymeric micelles to encapsulate poorly water-soluble weakly acidic and alkaline drugs.


Assuntos
Flavonoides/administração & dosagem , Poloxâmero/química , Polietilenoglicóis/química , Polivinil/química , Transdução de Sinais/efeitos dos fármacos , Administração Oral , Animais , Disponibilidade Biológica , Células CACO-2 , Cavéolas/metabolismo , Clatrina/metabolismo , Cães , Estudos de Viabilidade , Flavonoides/síntese química , Flavonoides/farmacocinética , Humanos , Masculino , Micelas , Nanopartículas , Tamanho da Partícula
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