The development of convenient methods for sulfur dioxide and its derivatives analysis is critically important because SO2 causes worldwide serious environmental problems and human diseases. In this ...work, we show an unprecedented example of an energy-transfer-based fluorescence nanoprobe for selective and quantitative detection of SO2, through molecular engineering of the fluorescent carbon nanodots by a cyanine dye which have a unique reactivity to bisulfite, achieving a detection limit of 1.8 μM with a linear relationship (R 2 = 0.9987). The specific detection was not interfered with other potential coexisted species. In addition, the probe is demonstrated for the determination of SO2 gas in aqueous solution as well as for visually monitoring of SO2 gas in air. This nanomaterial based probe is easily prepared, fast responding, and thus potentially attractive for extensive application for the determination of SO2 and other similar air pollutants.
A drug delivery system with near-infrared emissions response to drug delivery and release is essential as marking or targeting drug delivery system. For this reason, the Er
3+
-doped ZnAl-LDH with ...near-infrared emissions was used for the first time for controlled release of the ibuprofen (IBU) that is a non-steroidal antiinflammatory drug. The drug release was controlled in simulated intestinal medium (pH 7.4 phosphate buffer solutions at 37 °C). The release kinetics showed an initial burst release followed by a slow release of IBU. The most important thing is that the intercalation of IBU into the Er
3+
-doped ZnAl-LDH greatly reduced the near-infrared emissions of the Er
3+
-doped ZnAl-LDH, whereas the near-infrared emissions were recovered after the IBU was released from the Er
3+
-doped ZnAl-LDH delivery system. This change of near-infrared emissions would provide a useful technique for in situ monitoring of the delivery and release of IBU. The Er
3+
-doped ZnAl-LDH with near-infrared emissions is inexpensive, biocompatible, nontoxic, and little damage to biological tissue, which would be potential application as drug delivery system with marking or targeting performance.
ZnAl-Er-LDH drug delivery system exhibits great changes in the intensity of infrared emissions before drug delivery, during drug delivery, and after drug release. This change of infrared emissions would provide a useful technique for in situ monitoring of the delivery and release of ibuprofen at target sites.
Highlights
An infrared emission carrier for the delivery system of ibuprofen based on Er
3+
-doped ZnAl-LDH was reported for the first time.
The release kinetics of ibuprofen from the Er
3+
-doped ZnAl-LDH delivery system has been investigated.
The near infrared emissions of Er
3+
-doped LDH drug delivery system obviously response to the delivery and release of ibuprofen.
A drug delivery system with identification function is attractive and important. For this reason, the red fluorescence of Eu
3+
-doped ZnAl-LDH response to intercalation and release of ibuprofen ...(IBU) has been studied. X-ray diffraction(XRD) results showed that the basal spacing of the Eu
3+
-doped ZnAl-LDH varied from 8.85 to 12.04 Å after the intercalation of IBU. The release of the IBU from the Eu
3+
-doped ZnAl-LDH was carried out in simulated intestinal medium (phosphate buffer solutions with pH 7.4 and 37 °C), and the releasing behavior of IBU exhibited an initial rapid release followed by a slow release. Moreover, the present delivery system has slower release of drug than those of other LDH-based delivery systems. Interestingly, the intercalation of IBU into the Eu
3+
-doped ZnAl-LDH obviously reduced the red fluorescence of the Eu
3+
-doped ZnAl-LDH, whereas the red fluorescence was recovered after the release of IBU. This fluorescent responsiveness may be a favorable signal for detecting the delivery and release of IBU. Therefore, the Eu
3+
-doped ZnAl-LDH with red fluorescence would be potential application as drug delivery system with identification function because of its cheapness, non-toxicity, good biocompatibility, and little damage to biological tissue.
In this work, a flame retardant curing agent (DOPO-MAC) composed of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide DOPO and methyl acrylamide (MAC) was synthesized successfully, and the structure ...of the compound was characterized by FT-IR and
H-NMR. The non-isothermal kinetics of the epoxy resin/DOPO-MAC system with 1% phosphorus was studied by non-isothermal DSC method. The activation energy of the reaction (Ea), about 46 kJ/mol, was calculated by Kissinger and Ozawa method, indicating that the curing reaction was easy to carry out. The flame retardancy of the epoxy resin system was analyzed by vertical combustion test (UL94) and limiting oxygen index (LOI) test. The results showed that epoxy resin (EP) with 1% phosphorus successfully passed a UL-94 V-0 rating, and the LOI value increased along with the increasing of phosphorus content. It confirmed that DOPO-MAC possessed excellent flame retardance and higher curing reactivity. Moreover, the thermal stability of EP materials was also investigated by TGA. With the DOPO-MAC added, the residual mass of EP materials increased remarkably although the initial decomposition temperature decreased slightly.
A series of Er
3+
-doped hydrocalumite with strong infrared emissions have been synthesized by colloid precipitate method using CaCl
2
, AlCl
3
·6H
2
O, and ErCl
3
solid as reagents in ethanol/water ...medium. Compositional and structural analyses reveal that the Er
3+
-doped hydrocalumite can be kept the layered structure as the Ca
2+
/(Al
3+
+Er
3+
) molar ratio is of 1.10 – 2.31. All the Er
3+
-doped hydrocalumite are monoclinic symmetry despite their cell parameters are different. SEM images suggest that the Er
3+
doping does not damage the morphology of the hydrocalumite. Photoluminescent spectra show strong emissions at 720, 780, and 850 nm for all the Er
3+
-doped hydrocalumite, and the origins of these emissions have been discussed. The Er
3+
-doped hydrocalumite with strong red and infrared emissions may be potential application in biological detector or therapy in consideration of the biocompatibility of Ca
2+
ions.
Endometriosis has a high recurrence rate after treatment, and there are no effective recurrence predictors. LncRNA H19 has been found to be a predictor of the poor prognosis of multiple diseases. ...Here, we aimed to investigate the expression and clinical implications of lncRNAH19 in endometriosis and explore the clinical application value of lncRNAH19 for recurrence prediction. LncRNA H19 expression was evaluated in 104 ectopic and eutopic endometrial samples from patients with endometriosis and 50 control endometrial samples from patients without endometriosis. The association between lncRNA H19 expression and the clinical characteristics of endometriosis as well as its value as a potential predictor of recurrence were analyzed. LncRNA H19 expression in the ectopic and eutopic endometria of endometriosis patients was significantly higher than that in the normal endometrium. LncRNA H19 expression in the ectopic endometrium was associated with infertility, recurrence, bilateral ovarian lesions, an increased CA125 level, and revised American Fertility Society (rAFS) stage. Multivariate logistic regression analysis showed that age less than 40 years and lncRNA H19 overexpression in the ectopic endometrium were independent prognostic factors of endometriosis recurrence, and the receiver operating characteristic (ROC) curve showed that the sensitivity and specificity for predicting recurrence were 90.9% and 61.0%, respectively, when the lncRNA H19 expression level in the ectopic endometrium was higher than 0.0277. LncRNA H19 may be involved in the pathogenesis of endometriosis especially in the mechanism of recurrence and is a novel potential predictor of the recurrence of endometriosis.
Hydroformylation of olefins is widely used in the chemical industry due to its versatility and the ability to produce valuable aldehydes with 100% atom economy. Herein, a hybrid phosphate promoter ...was found to efficiently promote rhodium-catalyzed hydroformylation of styrenes under remarkably mild conditions with high regioselectivities. Preliminary mechanistic studies revealed that the weak coordination between the Rhodium and the P=O double bond of this pentavalent phosphate likely induced exceptional reactivity and high ratios of branched aldehydes to linear products.
Amongst all toxicological endpoints, carcinogenicity might pose the greatest concern. Genetic damage has been considered an important underlying mechanism for the carcinogenicity of chemical ...substances. The demand for in vitro genotoxic tests as alternative approaches is growing rapidly with the implementation of new regulations for compounds. However, currently available in vitro genotoxicity tests are often limited by relatively high false positive rates. Moreover, few studies have explored carcinogenicity potential by in vitro genotoxicity testing due to the shortage of suitable toxicological biomarkers to link gene damage with cancer risk. γ-H2AX is a recently acknowledged attractive endpoint (biomarker) for evaluating DNA damage and can simultaneously reflect the DNA damage response and repair of cells. We previously reported an ultrasensitive and reliable method, namely stable-isotope dilution-liquid chromatography–tandem mass spectrometry (ID-LC–MS/MS), for detecting cellular γ-H2AX and evaluating genotoxic chemicals. More importantly, our method can dynamically monitor the specific processes of genotoxic compounds affecting DNA damage and repair reflected by the amount of γ-H2AX. To clarify the possibility of using this method to assess the potential carcinogenicity of genotoxic chemicals, we applied it to a set of 69 model compounds recommended by the European Center for the Validation of Alternative Methods (ECVAM), with already-characterized genotoxic potential. Compared to conventional in vitro genotoxicity assays, including the Ames test, the γ-H2AX assay by MS has high accuracy (94–96%) due to high sensitivity and specificity (88% and 100%, respectively). The dynamic profiles of model compounds after exposure in HepG2 cells were explored, and a mathematical approach was employed to simulate and quantitatively model the DNA repair kinetics of genotoxic carcinogens (GCs) based on γ-H2AX time–effect curves up to 8 h. Two crucial parameters, i.e.,
k
(rate of γ-H2AX decay) and
t
50
(time required for γ-H2AX from maximum decrease to half) estimated by the least squares method, were achieved. An open web server to help researchers calculate these two key parameters and profile simulated curves of the tested compound is available online (
http://ccb1.bmi.ac.cn:81/shiny-server/sample-apps/prediction1/
). We detected a positive association between carcinogenic levels and
k
and
t
50
values of γ-H2AX in tested GCs, validating the potential of using this MS-based γ-H2AX in vitro assay to help preliminarily evaluate carcinogenicity and assess genotoxicity. This approach may be used alone or integrated into an existing battery of in vitro genetic toxicity tests.
Erbium-doped zinc-aluminum layered double hydroxide (Er
3+
-doped ZnAl-LDH) with near-infrared emission has been studied as the delivery and release of the 5-fluorouracil (5-Fu) which was an ...anticancer drug. Compositional and structural analyses reveal that the 5-Fu has been successfully intercalated into the interlayer of Er
3+
-doped ZnAl-LDH, and the basal spacing of the Er
3+
-doped LDH varied from 8.78 to 14.32 Å after the intercalation of 5-Fu. The release of 5-Fu was controlled in simulated intestinal medium (phosphate buffer solutions with pH 7.4 and 37 ℃). The releasing behavior of 5-Fu showed an initial quick-release followed by a slow-release. What is more, the intercalation of 5-Fu into the Er
3+
-doped ZnAl-LDH greatly reduced the near-infrared emissions of the Er
3+
-doped ZnAl-LDH, whereas the near-infrared emissions were recovered after the release of 5-Fu. The change of near-infrared emissions may be a useful technique for marking the delivery and release of 5-Fu at specific sites. Therefore, the Er
3+
-doped ZnAl-LDH with cheapness, non-toxicity, bio-compatibility, and little damage to biological tissue, may be a promising drug delivery system with marking or labeling function.
Background To investigate the differences in HPV genotypes and clinical indicators between cervical squamous cell carcinoma and adenocarcinoma and to identify independent predictors for ...differentiating cervical squamous cell carcinoma and adenocarcinoma. Methods A total of 319 patients with cervical cancer, including 238 patients with squamous cell carcinoma and 81 patients with adenocarcinoma, were retrospectively analysed. The clinical characteristics and laboratory indicators, including HPV genotypes, SCCAg, CA125, CA19-9, CYFRA 21-1 and parity, were analysed by univariate and multivariate analyses, and a classification model for cervical squamous cell carcinoma and adenocarcinoma was established. The model was validated in 96 patients with cervical cancer. Results There were significant differences in SCCAg, CA125, CA19-9, CYFRA 21-1, HPV genotypes and clinical symptoms between cervical squamous cell carcinoma and adenocarcinoma (P < 0.05). Logistic regression analysis showed that SCCAg and HPV genotypes (high risk) were independent predictors for differentiating cervical squamous cell carcinoma from adenocarcinoma. The AUC value of the established classification model was 0.854 (95% CI: 0.804-0.904). The accuracy, sensitivity and specificity of the model were 0.846, 0.691 and 0.899, respectively. The classification accuracy was 0.823 when the model was verified. Conclusion The histological type of cervical cancer patients with persistent infection of high-risk HPV subtypes and low serum SCCAg levels was more prone to being adenocarcinoma. When the above independent predictors occur, the occurrence and development of cervical adenocarcinoma should be anticipated, and early active intervention treatment should be used to improve the prognosis and survival of patients. Keywords: Cervical cancer, Adenocarcinoma, Squamous cell carcinoma, Human papilloma virus, Tumour marker
PDF
