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1.
Nanoscale ; 16(12): 5988-5998, 2024 Mar 21.
Article En | MEDLINE | ID: mdl-38465745

In this study, we demonstrate that palladium-platinum bimetallic nanoparticles (Pd@Pt NPs) as the nanozyme, combined with a multi-layer paper-based analytical device and DNA hybridization, can successfully detect Mycobacterium tuberculosis. This nanozyme has peroxidase-like properties, which can increase the oxidation rate of the substrate. Compared with horseradish peroxidase, which is widely used in traditional detection, the Michaelis constants of Pd@Pt NPs are fourteen and seventeen times lower than those for 3,3',5,5'-tetramethylbenzidine and H2O2, respectively. To verify the catalytic efficiency of Pd@Pt NPs, this study will execute molecular diagnosis of Mycobacterium tuberculosis. We chose the IS6110 fragment as the target DNA and divided the complementary sequences into the capture DNA and reporter DNA. They were modified on paper and Pd@Pt NPs, respectively, to detect Mycobacterium tuberculosis on a paper-based analytical device. With the above-mentioned method, we can detect target DNA within 15 minutes with a linear range between 0.75 and 10 nM, and a detection limit of 0.216 nM. These results demonstrate that the proposed platform (a DNA-nanozyme integrated paper-based analytical device, dnPAD) can provide sensitive and on-site infection prognosis in areas with insufficient medical resources.


Metal Nanoparticles , Mycobacterium tuberculosis , Hydrogen Peroxide/chemistry , Platinum/chemistry , Palladium/chemistry , Metal Nanoparticles/chemistry , DNA , Colorimetry
2.
Biosens Bioelectron ; 254: 116188, 2024 Jun 15.
Article En | MEDLINE | ID: mdl-38484412

Prussian blue analogues (PBAs) are promising materials due to their rich active sites and straightforward synthesis. However, their limited conductivity and electron transfer inefficiency hinder practical applications. This study utilizes a simple one-pot synthesis approach to produce a tungsten-disulfide (WS2) and iron-cobalt Prussian blue analogue composite (WS2-PBA), enhancing conductivity and electron transfer rate performance. Through the inclusion of sodium citrate into the solution, the S-edge site concentration of WS2 increases. This augmentation introduces additional active sites and defects into the catalyst, enhancing its catalytic activity. The effectiveness of the WS2-PBA 3D-Origami paper device for lactate detection in sweat is also evaluated for biomedical applications. The device demonstrated a robust relationship between the lactate concentration and current intensity (R2 = 0.997), with a detection limit of 1.83 mM. Additionally, this platform has successfully detected lactate in clinical sweat, correlating with the high-performance liquid chromatography test results, suggesting promising prospects for clinical diagnosis. In the future, the excellent catalytic and Rct performance of the WS2-PBA will enable its use in biomedical applications.


Biosensing Techniques , Sweat , Ferrocyanides , Lactic Acid
3.
Mikrochim Acta ; 187(4): 200, 2020 03 04.
Article En | MEDLINE | ID: mdl-32130538

In present study, we discovered unusual solvent-mediated aggregation-enhanced emission (AEE) character of 11-mercaptoundecanoic acid capped gold nanoclusters (MUA-Au NCs). When aggregated in aqueous media, the MUA-Au NCs showed strong emission, which was weakened by adding ethanol. Interestingly, the suppressed emission was selectively enhanced in the presence of hydrogen sulfide (H2S) because H2S was absorbed onto Au NCs through the strong sulfur-gold bonding affinity. The hydrolyzed H2S, namely, HS-, made the Au NCs negatively charged, which aggregated again due to decreased solubility. The H2S-mediated fluorescence enhancement can be further amplified by introducing a hydrophilic thiolate (glutathione, GSH) onto the surface of Au NCs (GSH/MUA-Au NCs), which enabled sensitive determination of H2S. Under the optimized condition, a detection limit of 35 nM was achieved. The determination was not interfered by other anions such as F-, Cl-, Br-, I-, OAc-, N3-, NO3-, HCO3-, SCN-, SO32-, and SO42-. This excellent sensing performance allowed practical application of the GSH/MUA-Au NC-based sensing platform to accurate determination of H2S in human serum samples. Graphical abstractUnusual aggregation-enhanced emission character of 11-mercaptoundecanoic acid capped gold nanoclusters is discovered and has been applied for fluorometric hydrogen sulfide detection.

4.
RSC Adv ; 10(21): 12619-12625, 2020 Mar 24.
Article En | MEDLINE | ID: mdl-35497578

Gold nanorods (GNRs) with desired longitudinal localized surface plasmon resonance (LLSPR) and strong scattering intensity are important for extending their practical applications in bioimaging and sensing. Herein, a simple additive (HCl and Na2S)-regulated overgrowth approach has been proposed for preparing GNRs with tunable LLSPR. In this approach, HCl is used to slow down the growth reaction rate by changing chemical equilibrium, while Na2S is utilized to halt the reaction when LLSPR is reaching the expected wavelength under monitoring by a UV-Vis spectrometer. Under optimal conditions, GNRs with an LLSPR range from 850 to 650 nm could be facilely prepared with a high precision of 3 nm deviation. The TEM images reveal that GNRs have high monodispersity, displaying an increase in both length and diameter but a decrease in the aspect ratio. With the increase in size, the produced GNRs show enhanced scattering intensity and are applicable for single nanoparticle imaging due to the enlarged absorption and scattering cross-section and improved matching efficiency toward the CCD response.

5.
Phytomedicine ; 56: 118-125, 2019 Mar 15.
Article En | MEDLINE | ID: mdl-30668332

BACKGROUND: The main symptoms of gastroesophageal reflux disease GERD are heartburn and acid regurgitation. Proton-pump inhibitors (PPI) are considered to be safe and effective for the treatment of GERD. In traditional Chinese medicine, wu chu yu tang (WCYT) is used to treat nausea after eating, vomiting, and diarrhea. PURPOSE: We designed a randomized, double-blind, placebo-controlled clinical trial to evaluate the therapeutic effect of WCYT on GERD using omeprazole as a PPI for the positive control. METHODS: Ninety patients with GERD were randomly assigned to the 1) control group (CG), who received an oral administration of omeprazole (20 mg) once per day and given WCYT placebo (3.0 g) three times per day for 4 weeks continuously; or the 2) treatment group (TG), who received oral administration of omeprazole (20 mg) placebo once per day and WCYT (3.0 g) three times per day for 4 weeks continuously. RESULTS: Seventy-seven patients (37 in CG, 40 in TG) completed the trial. Both Reflux Disease Questionnaire (RDQ) and Gastroesophageal Reflux Disease Questionnaire (GERDQ) scores was less in the second assessment (V2) and in the third assessment (V3) than those in V1 (first assessment; baseline) in the CG and TG groups (all p < 0.001); the score difference of both RDQ and GERDQ between V2 and V1 was similar between CG and TG (p = 1.00, p = 0.54, respectively). The score difference of both RDQ and GERD between V3 and V1 was less in the CG group than those of the TG group (both p = 0.004). CONCLUSION: WCYT has an effect similar to omeprazole for GERD treatment. Furthermore, this effect resulting from WCYT appeared to be maintained for a longer period of time than did that of omeprazole. A study with a larger sample size and longer study period is needed to corroborate our findings.


Alkaloids/therapeutic use , Gastroesophageal Reflux/drug therapy , Plant Extracts/therapeutic use , Quinolines/therapeutic use , Administration, Oral , Adult , Aged , Alkaloids/administration & dosage , Double-Blind Method , Evodia , Female , Humans , Male , Middle Aged , Omeprazole/administration & dosage , Omeprazole/pharmacology , Omeprazole/therapeutic use , Placebos , Plant Extracts/administration & dosage , Proton Pump Inhibitors/administration & dosage , Proton Pump Inhibitors/therapeutic use , Quinolines/administration & dosage , Treatment Outcome
6.
Article En | MEDLINE | ID: mdl-30445261

Citrate-capped gold nanoparticles (AuNPs) modified with thrombin-binding aptamer are often implemented for colorimetric, fluorescent, and electrochemical detection of thrombin in an aqueous solution. However, researchers have rarely explored the application of fibrinogen-modified AuNPs (F-AuNPs) for thrombin sensing. We present a simple, inexpensive, sensitive, and selective probe for colorimetric assay of thrombin through combining thrombin-induced inclusion of F-AuNPs into Fibrin and F-AuNPs-catalyzed reduction of 4-nitrophenol with an excess amount of NaBH4. Considering that fibrinogen stabilized citrate-capped AuNPs against a high-ionic-strength buffer, F-AuNPs efficiently catalyzed the NaBH4-mediated decrease of yellow 4-nitrophenol to colorless 4-aminophenol. The presence of thrombin converted fibrinogen into fibrin on the nanoparticle surface, leading to the inclusion of nanoparticles into fibrin. The formation of fibrin inhibited that the AuNPs catalyzed the NaBH4-mediated reduction of 4-nitrophenol. Consequently, the color of the solution gradually varied from colorless to yellow with increasing thrombin concentration. The proposed system was shown to be accurate in the quantification of small differences in the concentration of human thrombin over the range of 4-60 pM. The lowest detectable concentration of human thrombin by the naked eye was as low as 16 pM. We demonstrated the practical application of the proposed system in quantifying 1-15 nM human thrombin in human plasma.


Colorimetry/methods , Fibrin/chemistry , Fibrinogen/chemistry , Metal Nanoparticles/chemistry , Thrombin/analysis , Colorimetry/instrumentation , Female , Fibrin/metabolism , Fibrinogen/metabolism , Gold/chemistry , Humans , Nitrophenols/chemistry , Nitrophenols/metabolism , Sensitivity and Specificity , Young Adult
7.
Medicine (Baltimore) ; 97(40): e12552, 2018 Oct.
Article En | MEDLINE | ID: mdl-30290613

RATIONAL: Lymphangiomatosis is rare and benign, and slowly proliferating lymphatic vessels of unknown etiology and visceral lymphangiomatosis involving the spleen is rare. Since lymphangiomatosis may be asymptomatic or present as a sense of fullness, splenic cystic lymphangiomatosis is a disease of little concern. PATIENT CONCERNS: A 34-year-old woman suffering from progressive epigastric fullness after oral intake for two weeks. DIAGNOSES: Physical examination showed a palpable mass which was more than 10 cm in size over the left hypochondrium. An abdominal computed tomography disclosed marked splenomegaly with multiple cystic lesions in the spleen, causing external compression with right-sided deviation of the adjacent organs and varices in the upper abdomen. Esophagogastroduodenoscopy revealed portal hypertensive gastropathy. INTERVENTIONS: Conventional total splenectomy was performed in this patient because of an enlarged spleen and unknown etiology, preoperatively. Upon surgery, splenomegaly with polycystic content and varicose vessels over the omentum were noted. Autologous spleen transplantation was not performed because of limited orthotopic and vascularized spleen. OUTCOMES: The patient is doing well 18 months after splenectomy. LESSONS: This was a rare case presenting with splenic cystic lymphangiomatosis in association with omental varices and portal hypertension. Splenic cystic lymphangiomatosis should be considered in the differential diagnosis of patients with a palpable painless mass over the left hypochondrium.


Hypertension, Portal/complications , Lymphangioma/complications , Omentum/blood supply , Splenic Diseases/complications , Varicose Veins/complications , Adult , Female , Humans , Lymphangioma/classification , Lymphangioma/surgery , Omentum/pathology , Splenectomy/methods , Splenic Diseases/surgery
8.
J Microbiol Immunol Infect ; 50(3): 286-296, 2017 Jun.
Article En | MEDLINE | ID: mdl-25899133

BACKGROUND/PURPOSE: Effective mediators activate downstream transducers regulating inflammation and angiogenesis. Correlation among mediators IL-6, IL-27, TNF-α, and VEGF with STAT proteins at diverse clinical-pathologic stages of cirrhotic patients remains limited. METHODS: Plasma mediators were assayed from 158 naïve liver cirrhosis (LC-total group) and 144 non-LC individuals. The LC-total group included 69 hepatitis B virus-infected (LC-HBV) patients, 40 hepatitis C virus-infected (LC-HCV) patients, and 49 patients without HBV-/HCV- infection (LC-NBNC). Another 144 non-LC individuals comprised 54 healthy persons (HG) and 90 chronic hepatitis patients (CH-total) as the control group. To correlate with plasma mediators, 52 paired liver tissues (CH: 41 and LC: 11 cases) served for p-STAT1 and p-STAT3 immunostaining. RESULTS: Although IL-6, IL-27, TNF-α, and VEGF were expressed significantly in CH-total versus HG (p = 0.011, p < 0.001, p = 0.007, p = 0.004, respectively) and overall viral hepatitis patients versus HG (p < 0.001, p < 0.001, p < 0.001, p < 0.001, respectively), only IL-6 presented the strongest correlation in cirrhotic patients than noncirrhotic patients (LC-HBV vs. HG, p < 0.001, vs. CH-HBV, p = 0.001; LC-HCV vs. HG, p = 0.001, vs. CH-HCV, p = 0.031; LC-NBNC vs. HG, p < 0.001). Over-expressed IL-6 linked with poorer liver function (albumin: r = -0.346, p < 0.001; bilirubin: r = 0.271, p = 0.001; INR: r = 0.308, p < 0.001; Child-Turcotte-Pugh Classification C vs. A or B, p = 0.001, p = 0.007, respectively), variceal severity (p = 0.045), and bleeding (p = 0.047), as well as patients' mortality (p = 0.005). Furthermore, plasma IL-6 significantly correlated with tissues p-STAT3 expression (r = 0.737, p = 0.010) (IL-27: r = 0.078, p = 0.820; TNF-α: r = -0.145, p = 0.670; VEGF: r = 0.142, p = 0.678) in cirrhotic patients than noncirrhotic patients. CONCLUSION: Over-expression of IL-6 reflects hepatic dysfunction and varices bleeding with mortality, as well as correlates p-STAT3 expression in cirrhotic patients.


Esophageal and Gastric Varices/complications , Hemorrhage/epidemiology , Hemorrhage/mortality , Interleukin-6/blood , Liver Cirrhosis/complications , STAT3 Transcription Factor/blood , Adult , Aged , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Plasma/chemistry , Survival Analysis , Young Adult
9.
Biosens Bioelectron ; 92: 442-448, 2017 Jun 15.
Article En | MEDLINE | ID: mdl-27836604

We report citrate-capped platinum nanoparticles (Pt NPs) as oxidase mimetics for effectively catalyzing the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB), 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid), dopamine, and methylene blue in the presence of O2. To confirm oxidase-like activity of citrate-capped Pt NPs, their activity toward oxygen reduction reaction was studied using cyclic voltammetry and rotating ring-disk electrode method. The results obtained showed that Pt NP NPs can catalyze the oxidation of organic substrates to the colored product and the reduction of oxygen to water through a four-electron exchange process. Because the aggregation of Pt NPs can inhibit their oxidase-like activity and protamine can recognize heparin, we prepared the protamine-modified Pt NPs through direct adsorption on the surface of citrate-capped Pt NPs. The electrostatic attraction between heparin and protamine-stabilized Pt NPs induced nanoparticle aggregation, inhibiting their catalytic activity. Therefore, the lowest detectable heparin concentrations through UV-vis absorption and by the naked eye were estimated to be 0.3 and 60nM, respectively. Moreover, the proposed system enabled the determination of the therapeutic heparin concentration in a single drop of blood.


Anticoagulants/blood , Citric Acid/chemistry , Colorimetry/methods , Heparin/blood , Metal Nanoparticles/chemistry , Platinum/chemistry , Adult , Benzidines/chemistry , Biomimetic Materials/chemistry , Biosensing Techniques/methods , Catalysis , Humans , Limit of Detection , Male , Metal Nanoparticles/ultrastructure , Oxidation-Reduction , Oxidoreductases/chemistry , Oxygen/chemistry , Protamines/chemistry , Young Adult
10.
J Hazard Mater ; 324(Pt B): 420-427, 2017 Feb 15.
Article En | MEDLINE | ID: mdl-27856049

Most of the previously reported studies have focused on the change in the size, morphology, and composition of metal nanocatalysts for improving their catalytic activity. Herein, we report poly(diallyldimethylammonium chloride) [PDDA]-stabilized nanoparticles (NPs) of platinum (Pt) and palladium (Pd) as highly active and efficient catalysts for hydrogenation of 4-nitrophenol (4-NP) in the presence of NaBH4. PDDA-stabilized Pt and Pd NPs possessed similar particle size and same facet with citrate-capped Pt and Pd NPs, making this study to investigate the inter-relationship between catalytic activity and surface ligand without the consideration of the effects of particle size and facet. Compared to citrate-capped Pt and Pd NPs, PDDA-stabilized Pt and Pd NPs exhibited excellent pH and salt stability. PDDA could serve as an electron acceptor for metal NPs to produce the net positive charges on the metal surface, which provide strong electrostatic attraction with negatively charged nitrophenolate and borohydride ions. The activity parameter and rate constant of PDDA-stabilized metal NPs were higher than those of citrate-capped metal NPs. Compared to the previously reported Pd nanomaterials for the catalysis of NaBH4-mediated reduction of 4-NP, PDDA-stabilized Pd NPs exhibited the extremely high activity parameter (195s-1g-1) and provided excellent scalability and reusability.

11.
BMC Gastroenterol ; 16: 50, 2016 Apr 27.
Article En | MEDLINE | ID: mdl-27117280

BACKGROUND: Transarterial chemoembolization (TACE) and sorafenib are the therapeutic standard for intermediate and advanced stage hepatocellular carcinoma (HCC) patients respectively. High costs with adverse events (AE) of sorafenib might limit sorafenib dosage, further affecting therapeutic response. To attain greatest benefit, we evaluated the efficacy of different doses and effect of TACE during and after sorafenib discontinuation in patients representing Child-Pugh Classification Class A with venous or extra-hepatic invasion. METHODS: A total 156 patients met the criteria and were divided into Groups I (n = 52) accepting 800 mg/day; II (n = 58) accepting 800 mg/day and reduced to 400 mg/day owing to AE; and III (n = 46) accepting 400 mg/day. TACE was performed during and after sorafenib discontinuation and therapeutic response bimonthly to four-monthly was rated thereafter. RESULTS: Median duration of sorafenib treatment and patients' survival were 4.00 ± 0.45 and 7.50 ± 1.44 months in all cases; 2.50 ± 0.90 and 5.00 ± 1.10 months in Group I; 5.50 ± 1.27 and 16.50 ± 1.86 months in Group II; 4.00 ± 0.94 and 6.50 ± 2.49 months in Group III. Group II presented the best response and survival benefit (p = 0.010 and p = 0.011 respectively). Child-Pugh Classification score 5 (Hazard Ratio = 0.492, p = 0.049), absent AE (3.423, p = 0.015), tumor numbers ≤ 3 (0.313, p = 0.009), sorafenib duration ≤ 1 cycle (3.694, p = 0.004), and absent TACE (3.197, p = 0.008) significantly correlated with patient survival. TACE benefit appeared in separate and total cases during (p = 0.002, p = 0.595, p = 0.074, p = 0.002 respectively) and after discontinuation of sorafenib administration (p = 0.001, p = 0.034, p = 0.647, p = 0.001 respectively). CONCLUSIONS: Low-dosage sorafenib not only appeared tolerable and lowered economic pressure but also provided satisfactory results. TACE benefited patient's survival during and after sorafenib discontinuation.


Antineoplastic Agents/administration & dosage , Carcinoma, Hepatocellular/therapy , Chemoembolization, Therapeutic/methods , Liver Neoplasms/therapy , Niacinamide/analogs & derivatives , Phenylurea Compounds/administration & dosage , Adult , Aged , Aged, 80 and over , Dose-Response Relationship, Drug , Female , Humans , Male , Middle Aged , Niacinamide/administration & dosage , Proportional Hazards Models , Retrospective Studies , Sorafenib , Treatment Outcome
12.
BMC Gastroenterol ; 15: 50, 2015 Apr 25.
Article En | MEDLINE | ID: mdl-25908103

BACKGROUND: Biologic activities of functional mediators activate downstream transducers regulating inflammation and carcinogenesis. Correlation among mediators (IL-6, IL-27, TNF-α, and VEGF) with STAT proteins at diverse clinical-pathologic stages of hepatocellular carcinoma (HCC) remains limited. METHODS: Serum mediators assayed from 147 untreated HCC cases (HCC-total group) included 70 HBV-infected (HCC-HBV group), 64 HCV-infected (HCC-HCV group), and 13 without HBV-/HCV-infection (HCC-NBNC group). Another 156 non-HCC individuals comprised 54 healthy individuals (HG) and 102 chronic hepatitis patients (CH-total group) as control group. To correlate with serum mediators, 86-paired liver tissues (CH: 52 and HCC: 34 cases) served for p-STATs proteins immunostain. RESULTS: Although four mediators (IL-6, IL-27, TNF-α, and VEGF) significantly over-expressed, IL-6 presented the strongest correlation in HCC-total versus CH-total or HG groups (HCC-total versus CH-total: P < 0.001; HCC-total versus HG: P < 0.001). Over-expressed IL-6 concentration linked with poor liver function (Albumin: r = -0.383, P < 0.001; Bilirubin: r = 0.280, P = 0.001; INR: r = 0.299, P < 0.001; AST: 0.212, P = 0.016), tumor progression (TNM system: r = 0.370; P < 0.001), clinical condition severity (BCLC system: r = 0.471; P < 0.001; terminal- versus early-stage HCC, P = 0.001; advanced- versus early-stage HCC, P = 0.007; terminal- versus intermediate- stage HCC P = 0.003; advanced- versus intermediate-stage HCC P = 0.019), and 6-month mortality (P = 0.024). Likewise, serum IL-6 (r = 0.501, P = 0.003) as compared to IL-27 (r = 0.052, P = 0.770), TNF-α (r = 0.019, P = 0.917), and VEGF (r = 0.096, P = 0.595) expression reflected positive correlation with activation of tissues p-STAT3 rather than p-STAT1. CONCLUSIONS: Serum IL-6, through p-STAT3 rather than p-STAT1 signal pathway, affected hepatic function, tumor progression, and determine HCC patient survival.


Carcinogenesis/metabolism , Carcinoma, Hepatocellular , Interleukin-6/blood , Liver Neoplasms , Adult , Aged , Carcinogenesis/pathology , Carcinoma, Hepatocellular/blood , Carcinoma, Hepatocellular/chemistry , Carcinoma, Hepatocellular/mortality , Carcinoma, Hepatocellular/pathology , Cohort Studies , Female , Hepatitis B, Chronic/blood , Hepatitis B, Chronic/complications , Hepatitis C, Chronic/blood , Hepatitis C, Chronic/complications , Humans , Interleukin-27/blood , Liver Neoplasms/blood , Liver Neoplasms/chemistry , Liver Neoplasms/mortality , Liver Neoplasms/pathology , Male , Middle Aged , Phosphorylation , STAT1 Transcription Factor/analysis , STAT3 Transcription Factor/analysis , Signal Transduction , Tumor Necrosis Factor-alpha/blood , Vascular Endothelial Growth Factor A/blood
13.
Phys Chem Chem Phys ; 17(23): 15124-30, 2015 Jun 21.
Article En | MEDLINE | ID: mdl-25820836

This study describes the synthesis of fluorescent polydopamine dots (PDs) through hydroxyl radical-induced degradation of polydopamine nanoparticles. The decomposition of polydopamine nanoparticles to fluorescent PDs was confirmed using transmission electron microscopy and dark-field microscopy. The analysis of PDs by using laser desorption/ionization time-of-flight mass spectrometry revealed that the PDs consisted of dopamine, 5,6-dihydroxyindole, and trihydroxyindole units. Oligomerization and self-assembly of these units produced a broad adsorption band, resulting in an excitation-wavelength-dependent emission behavior. The maximal fluorescence of PDs appeared at 440 nm with a quantum yield of 1.2%. The coordination between the catechol groups of PDs and ferric ions (Fe(3+)) quenched the fluorescence of PDs; the limit of detection at a signal-to-noise ratio of 3 for Fe(3+) was determined to be 0.3 µM. The presence of pyrophosphate switched on the fluorescence of the PD-Fe(3+) complexes. Compared to the other reported methods for sensing Fe(3+), PDs provided simple, low-cost, and reusable detection of Fe(3+).


Hydroxyl Radical/chemistry , Indoles/chemistry , Nanoparticles/chemistry , Polymers/chemistry , Electron Transport , Ferric Compounds/chemistry , Nanoparticles/metabolism , Nanoparticles/ultrastructure , Quantum Theory , Spectrometry, Fluorescence
14.
ACS Appl Mater Interfaces ; 6(20): 17437-45, 2014 Oct 22.
Article En | MEDLINE | ID: mdl-25238563

This study describes a simple method for removing mercuric ions (Hg(2+)) from a high-salt matrix based on the use of Tween-20-stabilized gold nanoparticles (Tween 20-Au NPs) as Hg(2+) adsorbents and composites of reduced graphite oxide and Fe3O4 NPs as NP collectors. Citrate ions adsorbed on the surface of the Tween 20-Au NPs reduced Hg(2+) to Hg(0), resulting in the deposition of Hg(0) on the surface of the NPs. To circumvent time-consuming centrifugation and transfer steps, the Hg(0)-containing gold NPs were collected using reduced graphite oxide-Fe3O4 NP composites. Compared with the reported NP-based methods for removing Hg(2+), Tween 20-Au NPs offered the rapid (within 30 min), efficient (>99% elimination efficiency), durable (>10 cycles), and selective removal of Hg(2+), CH3Hg(+), and C2H5Hg(+) in a high-salt matrix without the interference of other metal ions. This was attributed to the fact that the dispersed Tween 20-Au NPs exhibited large surface-area-to-volume ratio to bind Hg(2+) through Hg(2+)-Au(+) metallophilic interactions in a high-salt matrix. The formation of graphite oxide sheets and reduced graphite oxide-Fe3O4 NP composites was demonstrated using X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy, Fourier transform infrared spectrometry, and transmission electron microscopy. The mechanism of interaction between Tween 20-Au NPs and Hg(2+) was studied using visible spectroscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy.

15.
Nanoscale ; 6(16): 9618-24, 2014 Aug 21.
Article En | MEDLINE | ID: mdl-24897557

We present a simple, one-pot approach for synthesizing ultrafine platinum (Pt) nanoclusters (NCs) under alkaline conditions using lysozyme (Lys) as a template. From the analysis of the nanoclusters by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, Lys VI-stabilized Pt NCs majorly consisted of Pt4 clusters. The formation of Pt NCs was confirmed using X-ray photoelectron spectroscopy and Fourier-transformed infrared spectroscopy. The maximal fluorescence of Pt NCs appears at 434 nm with a quantum yield of 0.08, a fluorescence lifetime of 3.0 ns, and excitation-dependent emission wavelength behavior. Pt NCs exhibit an intrinsic oxidase-like activity because Pt NCs can catalyze O2 oxidation of organic substrates through a four-electron reduction process. Compared with larger Pt nanoparticles, the Pt NCs produce substantially greater catalytic activity in the O2-mediated oxidation of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), 3,3',5,5'-tetramethylbenzidine, and dopamine.


Metal Nanoparticles/chemistry , Muramidase/chemistry , Oxidoreductases/metabolism , Platinum/chemistry , Hydrogen-Ion Concentration , Nanotechnology/methods , Oxidoreductases/chemistry
16.
Nanoscale ; 6(3): 1347-53, 2014.
Article En | MEDLINE | ID: mdl-24288017

Core etching of gold nanoparticles (AuNPs) into smaller-sized clusters is a classic method for fabricating gold nanoclusters (AuNCs). The top down-based synthesis of AuNCs includes two steps: (i) reducing the Au(3+) precursor solution to generate AuNPs in the presence of protecting ligands and (ii) core etching of the formed AuNPs into the AuNCs via ligand exchange. For the first time, this paper describes a one-step approach for preparing AuNCs using a top down approach. The sinapinic acid (SA)-induced formation of the AuNCs involved a three-step reaction process. First, large AuNPs (>200 nm) were quickly formed after mixing SA and the Au(3+) precursor solution. Second, excess SA molecules self-assembled on the NP surface, and large AuNPs were etched to small AuNPs via electrostatic repulsion between the neighboring SA molecules. Finally, SA-induced core etching of the AuNPs resulted in the formation of the AuNCs within 70 min. Furthermore, we showed that the presence of the AuNCs in SA was capable of suppressing crystal growth and eliminating the coffee-ring effect. Thus, proteins can be successfully quantified using the SA-AuNCs as matrices for matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Compared with using SA as matrices, the SA-AuNCs offered substantial advantages for improving shot-to-shot reproducibility and enhancing the ionization efficiency of proteins.


Coumaric Acids/chemistry , Gold/chemistry , Metal Nanoparticles/chemistry , Proteins/chemistry , Absorption , Acetonitriles/chemistry , Albumins/chemistry , Animals , Cattle , Chlorides/chemistry , Ethanol/chemistry , Gold Compounds/chemistry , Horses , Insulin/chemistry , Ions , Ligands , Myoglobin/chemistry , Nanotechnology/methods , Rabbits , Reproducibility of Results , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Static Electricity
17.
Hepatogastroenterology ; 61(131): 587-9, 2014 May.
Article En | MEDLINE | ID: mdl-26176040

BACKGROUND/AIMS: The incidence of gastric remnant carcinoma does not decrease after partial gastrectomy The aim of this study was to evaluate the clinical features and prognosis of gastric remnant carcinoma after treatment. METHODOLOGY: Among 412 gastric carcinoma patients who were admitted to our hospital 21 were found to have gastric remnant carcinoma. We analyzed their clinicopathological features and prognosis. RESULTS: Prognosis did not differ significantly in terms of gender, age, tumor-lymph node-metastasis stage, tumor location, and time interval between first and subsequent operations. However, it was influenced by intensive curative gastrectomy with or without resection of local lymph nodes. CONCLUSION: Long-term follow-up after gastrectomy, appropriate curative resection, as well as prevention and management of hypertensive disease co-mobility are important to improve survival rate of gastric remnant carcinoma operation.


Carcinoma/surgery , Gastrectomy , Gastric Stump/surgery , Stomach Neoplasms/surgery , Stomach Ulcer/surgery , Aged , Aged, 80 and over , Carcinoma/mortality , Carcinoma/pathology , Chemotherapy, Adjuvant , Comorbidity , Female , Gastrectomy/adverse effects , Gastrectomy/mortality , Gastric Stump/pathology , Humans , Hypertension/epidemiology , Hypertension/therapy , Lymph Node Excision , Male , Middle Aged , Neoplasm Staging , Reoperation , Risk Factors , Stomach Neoplasms/mortality , Stomach Neoplasms/pathology , Survival Analysis , Time Factors , Treatment Outcome
18.
Anal Chem ; 85(18): 8559-65, 2013 Sep 17.
Article En | MEDLINE | ID: mdl-23919280

We report that magnetite nanoparticles (Fe3O4 NPs) act as an efficient quencher for boron dipyrromethene-conjugated adenosine 5'-triphosphate (BODIPY-ATP) that is highly fluorescent in bulk solution. BODIPY-ATP molecules attached to the surface of Fe3O4 NPs through the coordination between the triphosphate group of BODIPY-ATP and Fe(3+)/Fe(2+) on the NP surface. The formed complexes induced an apparent reduction in the BODIPY-ATP fluorescence resulting from an oxidative-photoinduced electron transfer (PET) from the BODIPY-ATP excited state to an unfilled d shell of Fe(3+)/Fe(2+) on the NP surface. A comparison of the Stern-Volmer quenching constant between Fe(3+) and Fe(2+) suggests that Fe(3+) on the NP surface dominantly controls this quenching process. The efficiency for Fe3O4 NP-induced fluorescence quenching of the BODIPY-ATP was enhanced by increasing the concentration of Fe3O4 NPs and lowering the pH of the solution to below 6.0. We found that pyrophosphate and ATP compete with BODIPY-ATP for binding to Fe3O4 NPs. Thus, we amplified BODIPY-ATP fluorescence in the presence of increasing the pyrophosphate and ATP concentration; the detection limits at a signal-to-noise ratio of 3 for pyrophosphate and ATP were determined to be 7 and 30 nM, respectively. The Fe3O4 NP-based competitive binding assay detected ATP and pyrophosphate in only 5 min. The selectivity of this assay for ATP over metal ions, amino acids, and adenosine analogues is particularly high. The practicality of using the developed method to determine ATP in a single drop of blood is also validated.


Adenosine Triphosphate/analysis , Biosensing Techniques/methods , Boron Compounds/chemistry , Diphosphates/analysis , Fluorescent Dyes/chemistry , Magnetite Nanoparticles/chemistry , Adenosine Triphosphate/blood , Humans , Spectrometry, Fluorescence/methods
19.
Anal Chim Acta ; 745: 143-8, 2012 Oct 01.
Article En | MEDLINE | ID: mdl-22938619

We report a fluorescence approach for the highly selective and sensitive detection of catecholamines using magnetite nanoparticles (Fe(3)O(4) NPs) in the presence of Amplex UltraRed (AUR) and H(2)O(2). Fe(3)O(4) NPs catalyze H(2)O(2)-mediated oxidation of AUR. The resulting product fluoresces (excitation/emission maxima, ca. 568/587nm) more strongly, relative to AUR. When catecholamines bind to Fe(3)O(4), the complexes that are formed induce decreased activity of Fe(3)O(4) NPs, mediated through the coordination between Fe(3+) on the NP surface and the catechol moiety of catecholamines. As a result, Fe(3)O(4) NPs-catalyzed H(2)O(2)-mediated oxidation of AUR is inhibited by catecholamines. The limits of detection for dopamine (DA), L-DOPA, norepinephrine, and epinephrine were 3 nM, 3 nM, 3 nM, and 6 nM, respectively. The Fe(3)O(4) NPs-H(2)O(2)-AUR probe exhibited high selectivity (>1000-fold) toward catecholamines over other tested biomolecules that commonly exist in urine. Four catecholamines had similar sensitivity because the inhibition of the Fe(3)O(4) NPs activity relies on the presence of the catechol moiety. This approach also allowed the determination of tyrosinase activity because tyrosinase catalyzes the conversion of l-tyrosine to L-DOPA. We validated the practicality of the use of the Fe(3)O(4) NPs-H(2)O(2)-AUR probe for the determination of the concentrations of DA in urine samples.


Catecholamines/urine , Catechols/chemistry , Fluorescent Dyes/chemistry , Magnetite Nanoparticles/chemistry , Catalysis , Catecholamines/chemistry , Dopamine/chemistry , Dopamine/urine , Electrochemical Techniques , Epinephrine/chemistry , Epinephrine/urine , Fluorescence , Humans , Hydrogen Peroxide/chemistry , Levodopa/chemistry , Levodopa/urine , Limit of Detection , Magnetite Nanoparticles/ultrastructure , Male , Microscopy, Electron, Transmission , Monophenol Monooxygenase/urine , Norepinephrine/chemistry , Norepinephrine/urine , Oxidation-Reduction , Peroxidase , Reproducibility of Results , Sensitivity and Specificity , Spectrometry, Fluorescence , Surface Properties , Young Adult
20.
Liver Int ; 32(6): 928-36, 2012 Jul.
Article En | MEDLINE | ID: mdl-22230324

AIMS: Effective cytokines can drive the commitment of naive T cells to regulate immune response after antigen-mediated activation. Aims are to elucidate the clinical role of serum IL-27 and IL-6 in the different stages of naïve hepatitis B virus (HBV)-infected patients. METHODS: Samples with well-characterized clinical profiles were assessed from 395 HBV-infected patients including chronic hepatitis B (CHB) group in 291 patients, liver cirrhosis (LC) group in 57 patients, hepatocellular carcinoma (HCC) group in 47 patients. Another 139 non-HBV infected individuals were enrolled as control group (CG) including 104 with normal liver function (NF) and 35 with liver dysfunction (LD). RESULTS: The HBV-infected group and separated groups presented significantly higher IL-27 and IL-6 expression than the CG or subgroups of CG. In contrast to IL-27, IL-6 showed significant differences with deteriorating liver condition compared with LC or HCC with CHB groups. Furthermore, IL-6, rather than IL-27, showed significant statistical differences in patients with advanced liver disease compared with those of mild or moderate to severe liver disease and in patients with terminal stage HCC compared with those of early to intermediate or advanced stage HCC. The data associated with liver function, including Albumin, Bilirubin, INR, Platelet and AFP levels, were significantly correlated to IL-6 expression, but had weak correlation to IL-27 expression in HBV patients. CONCLUSION: Serum IL-27 can trigger immune response to prevent hepatic injury in different clinical-pathologic stages of HBV-infected patients earlier, but IL-6 may play an extremely important role to determine the liver progression.


Hepatitis B, Chronic/immunology , Interleukin-6/blood , Interleukins/blood , Liver/immunology , Adolescent , Adult , Aged , Aged, 80 and over , Biomarkers/blood , Carcinoma, Hepatocellular/immunology , Carcinoma, Hepatocellular/pathology , Case-Control Studies , Disease Progression , Female , Hepatitis B, Chronic/blood , Hepatitis B, Chronic/diagnosis , Hepatitis B, Chronic/pathology , Humans , Liver/pathology , Liver Cirrhosis/immunology , Liver Cirrhosis/pathology , Liver Function Tests , Liver Neoplasms/immunology , Liver Neoplasms/pathology , Male , Middle Aged , Predictive Value of Tests , Severity of Illness Index , Taiwan , Young Adult
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