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1.
Food Chem ; 304: 125425, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31476549

RESUMO

Ceramide 2-aminoethylphosphonate (CAEP) is a type of phosphonosphingolipids with potential trophic activity. In this work, complicated CAEP species from different aquatic products were comprehensively identified and semi-quantified by utilizing normal phase liquid chromatography/Q-Exactive mass spectrometry (NPLC/Q-Exactive-MS). We elucidated the fragment schemes of CAEP molecules and found the presence of methylated CAEP (Me-CAEP) species. Remarkably, quantitative results revealed that Loligo chinensis had the highest CAEP content of 4.9 ±â€¯0.4 mg/g dry weight and the most complex molecular species composition, whereas Asterias amurenis had the lowest CAEP content of 1.9 ±â€¯0.6 mg/g dry weight. The most common molecule was CAEP (d19:3-16:0). Additionally, statistical analysis revealed that five aquatic products can be effectively distinguished from their CAEP species; thus, CAEP molecules can play an important role in identifying processed products from aquatic products.

2.
Talanta ; 207: 120261, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31594567

RESUMO

Significant progress on circulating tumor cells (CTCs) has profound impact for noninvasive tumor profiling including early diagnosis, treatment monitoring, and metastasis recognition. Therefore, CTCs based liquid biopsy technology is taking a rapid growth in the field of precision oncology. The label-free approaches relied on microfluidic chip stand out from a crowd of methods that suffer from time consuming, extensive blood samples, lost target cells and labor-intensive operation. In this paper, a label-free separation microfluidic device was developed using multistage channel, which took full advantage of inertial lift force. Our strategy demonstrated CTCs were efficiently isolated from untreated human blood samples including antibody conjugation and erythrocyte lysis. This device was applied for isolating human brain malignant glioma cells that were spiked in human peripheral blood samples. The experimental condition was optimized and exhibited an average separation efficiency of ≥ 90% across cell morphological analysis, up to 84.96% purity of collected CTCs and the viability of all cells is >95%, which was better than other one-step CTCs separation methods. Furthermore, the CTCs were successfully separated from untreated clinical blood sample of cancer patient on the proposed microfluidic device. The entire experimental procedures are extremely low-cost and easy manipulation. It is believed that the proposed multistage microfluidic chip can become a promising tool for CTCs separation and early diagnosis of cancer.

3.
Talanta ; 207: 120292, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31594617

RESUMO

12CaO·7Al2O3 (C12A7) single crystal had extraordinary application in optical field, owing to its special structure. Here, Yb3+ and Er3+ co-doped C12A7 single crystal (Er3+/Yb3+/C12A7) were prepared by Czochralski method. XRD patterns of C12A7 single crystal performed a single diffraction peak, indicating that pure single structure was achieved. With over-stoichiometric ratio, infrared absorption spectrum had two peaks between 600 cm-1 and 850 cm-1, which belonged to the frame structure of C12A7 single crystal. The band gap of Er3+/Yb3+/C12A7 single crystal was 4.25 eV, which reduced the temperature quenching of Ln3+ ions. Raman scattering spectra showed that the highest phonon energy of C12A7 single crystal was about 880 cm-1, which was beneficial for upconversion emission. The temperature sensitivity coefficient of Er3+/Yb3+/C12A7 polycrystal and single-crystal were 1124.81 and 1122.69 range from 373 K to 573 K, respectively. Compared with polycrystal, sensitivity coefficient of Er3+/Yb3+/C12A7 single crystal increased. Moreover, absolute sensitivity (SA) of single crystal of Er3+/Yb3+/C12A7 increased with the increasing of temperature, suggesting single crystal was suitable for detecting high temperature.

4.
J Colloid Interface Sci ; 558: 211-219, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31586740

RESUMO

Porous interconnected carbon nanosheets (PICNs) with high electrochemical performance were prepared by doping urea and a co-hydrothermal precursor derived from soybean stalk (SS) and nickel nitrate. The specific surface area and average pore diameter of the as-synthesized PICNs are 2226.29 m2 g-1 and 1.89 nm, and their N and O contents are 5.08% and 9.4%, respectively, which is beneficial for increasing pseudocapacitance. Furthermore, the doping of the metal Ni increases the graphitization degree of the PICNs and promotes the conversion of pyridine-N to graphitized-N. Therefore, the PICNs possess a high specific capacitance of 407 F g-1 at a current density of 0.5 A g-1, a high capacitance retention of 78.62% even at 20 A g-1, and an outstanding cycling stability (over 93% retention rate after 10,000 charge/discharge cycles). Moreover, an energy density of 36.11 W h kg-1 is achieved at a power density of 517.8 W kg-1 during a two-electrode system test, and a retention rate of 87.5% is obtained after 10,000 cycles. This co-hydrothermal treatment as well as nitrogen-doping approach for preparing porous interconnected carbon from SS not only represents an alternative strategy for carbon-based supercapacitor materials but also provides a new option for the utilization of waste SS.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31679689

RESUMO

Ischemic stroke is a leading cause of mortality and disability worldwide. Nevertheless, its molecular mechanisms have not yet been adequately illustrated. Progranulin (PGRN) is a secreted glycoprotein with pleiotropic functions. In the present study, we found that PGRN expression was markedly reduced in mice after stroke onset through middle cerebral artery occlusion (MCAO). We also showed that necroptosis was a mechanism underlying cerebral I/R injury. Importantly, PGRN knockdown in vivo significantly promoted the infarction volume and neurological deficits scores in mice after MCAO surgery. Necroptosis induced by MCAO was further accelerated by PGRN knockdown, as evidenced by the promoted expression of phosphorylated receptor-interacting protein (RIP) 1 kinase (RIPK1), RIPK3 and mixed lineage kinase domain-like (MLKL), which was accompanied with increased expression of cleaved Caspase-8 and Caspase-3. However, PGRN over-expression was neuroprotective. Additionally, PGRN-regulated ischemic stroke was related to ROS accumulation that MCAO-mice with PGRN knockdown exhibited severe oxidative stress, as proved by the aggravated malondialdehyde (MDA) and lipid peroxidation (LPO) contents, and the decreased superoxide dismutase (SOD) activity. However, PGRN over-expression in mice with cerebral ischemia showed anti-oxidative effects. Finally, PGRN was found to attenuate oxidative damage partly via its regulatory effects on necroptosis. Therefore, promoting PGRN expression could reduced cerebral I/R-induced brain injury by suppressing neroptosis and associated reactive oxygen species (ROS) production. These data elucidated that PGRN might provide an effective therapeutic treatment for ischemic stroke.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31682264
7.
Nano Lett ; 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31671946

RESUMO

Despite rapid advancements in antitumor drug delivery, insufficient intracellular transport and subcellular drug accumulation are still issues to be addressed. Cancer cell membrane (CCM)-camouflaged nanoparticles (NPs) have shown promising potential in tumor therapy due to their immune escape and homotypic binding capacities. However, their efficacy is still limited due to inefficient tumor penetration and compromised intracellular transportation. Herein, a yolk-shell NP with a mesoporous silica nanoparticle (MSN)-supported PEGylated liposome yolk and CCM coating, CCM@LM, was developed for chemotherapy and exhibited a homologous tumor-targeting effect. The yolk-shell structure endowed CCM@LM with moderate rigidity, which might contribute to the frequent transformation into an ellipsoidal shape during infiltration, leading to facilitated penetration throughout multicellular spheroids in vitro (up to a 23.3-fold increase compared to the penetration of membrane vesicles). CCM@LM also exhibited a cellular invasion profile mimicking an enveloped virus invasion profile. CCM@LM was directly internalized by membrane fusion, and the PEGylated yolk (LM) was subsequently released into the cytosol, indicating the execution of an internalization pathway similar to that of an enveloped virus. The incoming PEGylated LM further underwent efficient trafficking throughout the cytoskeletal filament network, leading to enhanced perinuclear aggregation. Ultimately, CCM@LM, which co-encapsulated low-dose doxorubicin and the poly(ADP-ribose) polymerase inhibitor, mefuparib hydrochloride, exhibited a significantly stronger antitumor effect than the first-line chemotherapeutic drug Doxil. Our findings highlight that NPs that can undergo facilitated tumor penetration and robust intracellular trafficking have a promising future in cancer chemotherapy.

8.
Environ Toxicol ; 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31691492

RESUMO

Microcystin-leucine arginine (MC-LR) is a cyclic heptapeptide, produced by aquatic cyanobacteria such as microcystis, with strong reproductive toxicity which poses greater threat to the reproductive abilities of humans and animals. By exploring the role of trimethylation of histone H3 at lysine 4 (H3K4me3) and the role of oxidative stress in MC-LR-induced apoptosis in testicular Sertoli cells in Sprague-Dawley (SD) rats, this study indicated that MC-LR increased the expression levels of apoptosis-related genes by raising the levels of H3K4me3. 5'-Deoxy-5'-methylthioadenosine (MTA), the inhibitor of H3K4me3, reduced apoptosis, indicating for the first time that epigenetic modification is closely related to the testicular reproductive toxicity induced by MC-LR. MC-LR also induced oxidative stress by stimulating the generation of reactive oxygen species (ROS), and subsequently triggering mitochondria-mediated apoptotic pathway by decreasing mitochondrial membrane potential and increasing the levels of Bax, Bcl-2, Caspase-3, and so on. MC-LR-induced apoptosis of testicular cells could be decreased after pretreatment with oxidative stress inhibitor N-acetyl-cysteine (NAC). Furthermore, the pathological damage to mitochondria and testes were observed in SD rats. These results show that MC-LR can induce apoptosis by raising the levels of H3K4me3, and pretreatment with MTA can ameliorate the MC-LR-induced apoptosis of cocultured cells by lowering the levels of H3K4me3. Furthermore, NAC has a protective effect on MC-LR-induced apoptosis of testicular cells in SD rats by inhibiting the oxidative stress.

9.
Bioinformatics ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31693067

RESUMO

A critical aspect for exploring the biological function of a microRNA (miRNA) lies on exact detection and validation of its target mRNAs. However, no convenient and efficient web-based server is available for plant biologists to identify the experimentally verified target mRNAs of miRNAs. In this work, we built a comprehensive web-based platform for miRNA-target analysis, named as Whole-degradome-based Plant MiRNA-target Interaction Analysis Server (WPMIAS), for validation of predicted interactions of miRNAs and their target mRNAs (MTIs) by user-submitted data or all available pre-loaded degradome data. Besides, the server can construct degradome-based miRNA regulatory networks (MRNs) based on the validated MTIs to help study the functions and relations among miRNAs and target mRNAs. WPMIAS is also suitable for other small RNAs (sRNAs), such as 21-nt phased siRNAs (phasiRNAs) and natural antisense siRNAs (nat-siRNAs), which direct cleavage of target mRNAs. Currently, WPMIAS supports 64 plant species with ∼200 cDNA libraries and 274 pre-loaded plant degradome datasets. The user can identify all validated MTIs by analyzing all degradome data at a time and understand when and where MTIs take place and their cleavage levels. With the data obtained from WPMIAS, the user can build a plant miRNA-target map, where it is convenient to find interesting research ideas on miRNAs. In summary, WPMIAS is able to support a comprehensive web-based plant miRNA-target analysis and expected to greatly promote future research on plant miRNAs. AVAILABILITY: It can be freely accessed at https://cbi.njau.edu.cn/WPMIAS/. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

10.
Appl Opt ; 58(30): 8302-8308, 2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31674505

RESUMO

A volume grating-based holographic pressure sensor in acrylamide photopolymer has been studied. The pressure sensing response is analyzed using a diffraction spectrum in two kinds of sensor construction methods, i.e., transmission and reflection. In a transmission sensor, the maximum of peak wavelength shifts up to 25 nm under ${1.58} \times {{10}^5}\,\,{\rm Pa}$1.58×105Pa pressure. The linear pressure response range exceeds ${2.0} \times {{10}^5}\,\,{\rm Pa}$2.0×105Pa and the optimized sensitivity is ${4.9} \times {{10}^3}\,\,{\rm Pa}/{\rm nm}$4.9×103Pa/nm. Compared to the reflection sensor, the transmission sensor with large slanted angle can provide a more excellent sensing performance. The linear and reversible peak wavelength shifts confirm the applicability of the holographic pressure sensor. A photopolymer-based holographic pressure sensor is expected to apply in a cheap and visual pressure sensing field. The transmission grating is a significant candidate for developing the holographic sensor. These experimental results can accelerate the development and practicality of holographic optical elements.

11.
Artigo em Inglês | MEDLINE | ID: mdl-31676397

RESUMO

OBJECTIVE: We performed a systematic review and meta-analysis with the aim to answer whether operative laparoscopy is an effective treatment in a woman with demonstrated endometriosis as compared to alternative treatments. We also aimed to assess the risks of operative laparoscopy as compared to alternatives. In addition, we aimed to systematically review the literature on the impact of patient preference on decision-making around surgery. DATA SOURCES: We searched MEDLINE, EMBASE, PsycINFO, ClinicalTrials.gov, CINAHL, Scopus, OpenGrey and Web of Science from inception through May 2019. Additionally, a manual search of reference lists of relevant studies was also conducted. METHODS OF STUDY SELECTION: Published and unpublished randomized controlled trials (RCT) in any language describing a comparison between surgery and any other intervention were included, with particular reference to timing and its impact on pain and fertility. Studies reporting on keywords including, but not limited to, endometriosis, laparoscopy, pelvic pain, infertility were included. In the anticipated absence of RCTs on patient preference, all original research on this topic was considered eligible. TABULATION, INTEGRATION, AND RESULTS: In total, 1990 studies were reviewed. Twelve studies were identified as being eligible for inclusion to assess outcomes of pain (n = 6), fertility (n = 7), quality of life (n = 1), and disease progression (n = 3). Seven studies were identified as being of interest to evaluate patient preferences. There is evidence that operative laparoscopy may improve overall pain levels at six months compared to diagnostic laparoscopy (relative risk (RR), 2.65; 95% confidence interval (CI), 1.61-4.34; p < .001; 2 RCTs, 102 participants; low quality evidence). Since the quality of the evidence was very low, it is uncertain if operative laparoscopy improves live birth rates. Operative laparoscopy probably yields little or no difference on clinical pregnancy rates compared to diagnostic laparoscopy (RR, 1.29; 95% CI, 0.99-1.92; p = .06; 4 RCTs, 624 participants; moderate quality evidence). It is uncertain if operative laparoscopy yields a difference in adverse outcomes when compared to diagnostic laparoscopy (RR, 1.98; 95% CI, 0.84-4.65; p = .12; 5 RCTs, 554 participants; very low quality evidence). No studies reported on progression of endometriosis to a symptomatic state or progression of extent of disease in terms of volume of lesions and/or locations in asymptomatic women with endometriosis. We found no studies that reported on the timing of surgery. No quantitative or qualitative studies specifically aimed at elucidating the factors informing a woman's choice for surgery were identified. CONCLUSION: Operative laparoscopy may improve overall pain levels, but may have little or no difference for fertility-related or adverse outcomes when compared to diagnostic laparoscopy. Additional high quality RCTs, including comparing surgery to medical management, are needed and these should also report adverse events as an outcome. Studies on patient preference in surgical decision-making are needed.

12.
Chemosphere ; 241: 125073, 2019 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-31683423

RESUMO

Microcystin-leucine arginine (MC-LR) is a variant of microcystins (MCs), which poses a serious threat to the reproductive system. Histone acetylation modification can regulate the expressions of apoptosis-related genes. However the mechanisms of histone acetylation involving MC-LR-induced apoptosis were not understood. This study investigated the change of histone acetylation and its role in apoptosis and cell cycle arrest induced by MC-LR. MC-LR enhanced the activity of histone deacetylase (HDAC), decreased the activity of histone acetylase (HAT), up-regulated the expression of HDAC1, and down-regulated the expressions of Ac-H3 and Ac-H4 in vitro and vivo. Meanwhile, MC-LR induced testicular tissue injury and increased the expressions of apoptosis-related genes, such as Bax, Caspase3 and Caspase8, ultimately causing cells apoptosis in testicular tissues. Furthermore, MC-LR also induced cell cycle arrest in S phase, increased the expression of P21Wif1/Cip1, and inhibited the expressions of cyclinD1, cyclinE1, CDK2 and E2F1. Importantly, HDAC inhibitor Trichostatin A (TSA) could ameliorate MC-LR-induced apoptosis and cell cycle arrest by reverse-regulating the expressions of these proteins. These results indicated that MC-LR could activate the mitochondrial apoptotic pathway and disorder the cell cycle pathway to induce the cell apoptosis by enhancing HDAC activity and reducing histone acetylation of normal testicular cells in SD rats. Hence, histone acetylation has a vital function in MC-LR-induced apoptosis in SD rat testicular cells, which provides a new insight on the reproductive toxicity of male induced by MC-LR.

13.
Acta Neurol Scand ; 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31715011

RESUMO

OBJECTIVE: Increased permeability and changes in gut microbiota contributed to the pathogenesis of Alzheimer's disease (AD). Zonulin is a key modulator that regulates intestinal barrier function. Peripheral platelet alterations have been involved in AD pathology. C-type lectin-like receptor 2 (CLEC-2) is a receptor on the platelet surface for activation. The purpose of this study was to determine zonulin and CLEC-2 levels in MCI and AD, and investigate the relationship between zonulin and CLEC-2. METHODS: In this study, CLEC-2 and zonulin levels were measured using ELISA assay in 110 AD patients, 110 MCI patients, and 110 non-demented control subjects. RESULTS: Increased CLEC-2 and zonulin levels were observed in MCI and AD patients. Furthermore, AD patients had higher CLEC-2 and zonulin levels compared with MCI patients. In addition, CLEC-2 levels were positively correlated with zonulin levels, after adjusting confounding factors (r = 0.592, p < 0.001). Multivariate analysis revealed that increased CLEC-2 and zonulin levels were significantly associated with reduced mini-mental state examination (MMSE) score. CONCLUSIONS: CLEC-2 is correlated with zonulin after adjusting confounding covariates. Moreover, increased CLEC-2 and zonulin are the significant factors for reduced MMSE score in MCI and AD. Further studies are needed.

14.
Biomed Res Int ; 2019: 4213623, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31687389

RESUMO

Background. To clarify the efficacy of hepatectomy for gastric cancer liver metastasis (GCLM) and to investigate the association between prognostic nutrition index (PNI) or neutrophil-to-lymphocyte ratio (NLR) and prognosis of GCLM undergoing or without hepatectomy. Methods. We retrospectively studied 374 patients with GCLM. The ROC curve was used to determine the optimal cut-off of PNI and NLR. Patients were divided into groups based on whether hepatectomy was performed, and survival analysis was conducted before and after grouping. The overall survival (OS) time and 1, 3, 5-year survival rates were also compared. Results. Multivariate analysis of all GCLM patients revealed that hepatectomy (p = 0.001) was an independent prognosis factor. And there were statistical differences in OS and 1, 3, 5-year survival rates (p = 0.001 of all) between hepatectomy group and nonhepatectomy group. Multivariate analysis of GCLM undergoing hepatectomy showed that PNI was an independent prognosis factor (p = 0.001). And there were statistical differences in OS and 1, 3, 5-year survival rates (p = 0.001p = 0.005, p = 0.001 and p = 0.020, respectively) between high PNI group and low PNI group. Multivariate analysis of GCLM without hepatectomy showed that NLR was an independent prognosis factor (p = 0.001). And there were statistical differences in OS and 1, 3, 5-year survival rates (p = 0.001p = 0.008p = 0.031 and p = 0.026, respectively) between low NLR group and high NLR group. Conclusions. GCLM has a better prognosis with hepatectomy. High preoperative PNI is a benign prognostic predictor for patients undergoing hepatectomy. And high preoperative NLR is an adverse prognostic factor for patients without hepatectomy.

15.
J Cardiothorac Surg ; 14(1): 191, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31699143

RESUMO

BACKGROUND: Mild preoperative renal dysfunction (RD) is not rare in patients receiving isolated cardiopulmonary coronary artery bypass grafting (CCABG). However, there are not too many studies about the impact of mild preoperative RD on in-hospital and follow-up outcomes after isolated CCABG. This single-centre, retrospective propensity score matching study designed to study the impact of mild preoperative RD on in-hospital and long-term outcomes after first isolated CCABG. METHODS: After propensity score matching, 1144 patients with preoperative estimated glomerular filtration rate (eGFR) of more than 60 ml/min/1.73 m2 receiving first isolated CCABG surgery from January 2012 to December 2015 entered the study, who were divided into 2 groups: A group (eGFR ≥90 ml/min/1.73 m2, n = 572) and B group (eGFR of 60-89 ml/min/1.73 m2, n = 572). The in-hospital and long-term outcomes were recorded and analyzed. The mean follow-up time was 54.4 ± 10.7 months. Acute kidney injury (AKI) was defined and classified according to the Acute Kidney Injury Network (AKIN) criteria. RESULTS: The 2 propensity score-matched groups had similar baseline and procedure except the baseline eGFR. There were 8 patients died in A group (mortality is 1.4%) and 14 died in B group (mortality is 2.5%) during the in hospital and 30-day postoperatively(χ2 = 1.159, p = 0.282). There were totally 38 patients lost to follow-up, 18 in group A and 20 in group B. 21 patients died in group A and 37 died in group B during the follow-up, and long-term survival in group A was higher than in group B (96.2% vs 93.1%, χ2 = 4.336, p = 0.037). Comparing with group A, group B was associated with an increased rates and severity of AKI postoperatively (total AKI: 62 vs 144. AKIN stageI: 54 vs 113; AKIN stageII: 6 vs 22; AKIN stageIII: 2 vs 9, p<0.0001). During follow-up, group B also had a higher rate of new onset of dialysis (0 vs 6, χ2 = 4.432, p = 0.039). Multivariable logistic regression showed that comparing with A group, the HR for long-term mortality and new onset of dialysis in B group was 1.67 and 1.52 respectively (95%CI 1.09-2.90, p = 0.035; 95%CI 1.14-2.49, p = 0.027). CONCLUSIONS: Comparing with normal preoperative renal function, patients with mild preoperative RD had a similar in-hosptial mortality, but with an increased in-hosptial rates and severity of AKI, and with a decreased long-term survival and increased long-term new onset of dialysis.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31728508

RESUMO

BACKGROUND: There may be a beneficial effect on lipid levels in Shenzhen in recent years. In this study, we aimed to examine trends in serum lipids in population in Shenzhen between 2009 and 2015. METHODS: We enrolled 2210 adults aged 18-70 years from two independent cross-sectional studies conducted in 2009 and 2015. Blood lipid profiles, such as total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C), were measured. Chi-square test, t-test and multivariate logistic regression analysis were applied for data analysis. RESULTS: From 2009 to 2015, mean LDL-C declined from 3.05 ± 0.76 mmol/L in 2009 to 2.27 ± 0.75 mmol/L in 2015 (P < 0.001). Similarly, a significant 7.09% decrease in the prevalence of high LDL-C was observed over the same period (P < 0.001). There was an increasing trend in the prevalence of low HDL-C among adults in Shenzhen (P < 0.001). A no-significant increase in prevalence of dyslipidemia was also observed over this 6-year interval (P = 0.139). The prevalence of dyslipidemia was closely related with increasing age, male gender, current smoker, diabetes, obesity and overweight. CONCLUSION: This study shows a favourable downward trend in LDL-C concentration in Shenzhen. However, more intense strategies are needed to control dyslipidemia.

17.
J Hazard Mater ; : 121509, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31708288

RESUMO

Degradation of brominated flame retardants (BFRs) in waste printed circuit boards (WPCBs) occurred due to mechanical force during the crushing process. In this study, a planetary ball-milling simulation experiment was designed to explore the mechanochemical debromination process of BFRs in WPCBs. The results showed that CaO had a better debromination performance than MgO and the mixture of Fe + SiO2, and high revolution speed and low mass ratio of WPCBs to CaO promoted the degradation of BFRs. After milling for 1 h, the particle size distribution was stable while the debromination efficiency increased with the increase of milling time. Ball milling promoted the migration of bromine from the inside to the new surface of WPCBs powder, and submicron particles adhered to the micron size aggregates. The polybrominated diphenyl ethers (PBDEs) detection showed that the concentrations of most PBDE congeners decreased with the increase of milling time, and a possible degradation pathway was proposed according to the experimental results. All the results provided new data for the mechanism of degradation of BFRs in WPCBs during the mechanical crushing process.

18.
Molecules ; 24(22)2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31703370

RESUMO

As our ongoing research project on Ban Lan Gen (Isatis tinctoria roots), a total of 23 alkaloids were obtained. Compounds 1 and 2 contain an unusual C-C bond between the 2(1H)-quinolinone moiety and the phenol moiety and between the 2(1H)-quinolinone moiety and the 1H-indole moiety, respectively. Compound 3 possesses an unusual carbon skeleton and its putative biosynthetic pathway was discussed, and Compound 23 was deduced as a new indole alkaloid glycoside. Compounds 4-7 were identified as four new natural products by extensive spectroscopic experiments. Additionally, the anti-inflammatory activity was assessed based on nitric oxide (NO) production using Lipopolysaccharide-stimulated RAW264.7 macrophages. Compounds 9, 15, and 17 showed inhibitory effects with IC50 values of 1.2, 5.0, and 74.4 µM.

19.
J Colloid Interface Sci ; 560: 284-292, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31670101

RESUMO

In this work, the chitosan wrapped multiwalled carbon nanotubes (MWCNTs-CS) composited material was prepared by surface deposition and crosslinking method. This mild process can maintain the unique properties of the original carbon nanotubes intact. The morphological character of MWCNTs-CS was examined via Fourier transform infrared spectroscopy and field emission scanning electron microscopy. MWCNTs-CS was used as sensing film to fabricate quartz crystal microbalance (QCM) humidity sensors. The optimized sensor possesses high response sensitivity (46.7 Hz/% RH), negligible humidity hysteresis (around 1.1% RH), quick response and recovery time (75 s/34 s), and remarkable reversibility, repeatability, long-term stability and selectivity. Langmuir adsorption isotherm model was used to study the adsorption process of water molecules on MWCNTs-CS film, and the Gibbs free adsorption energy was calculated as -21.85 kJ/mol. By combining the good mechanic properties of MWCNTs and the high hydrophilia of chitosan, the MWCNTs-CS composites are promising for humidity sensing application.

20.
Mol Med Rep ; 20(5): 4523-4532, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31702044

RESUMO

Betatrophin [also known as lipasin, angiopoietin­like 8 (ANGPTL8), refeeding induced in fat and liver (RIFL), or hepatocellular carcinoma­associated gene TD26], a 22­kDa protein in the angiopoietin­like family, is a liver­derived hormone that promotes pancreatic ß­cell proliferation and lipid metabolism. The aim of the present study was to investigate the effect of recombinant betatrophin on ß­cell regeneration in a neonatal streptozotocin (STZ)­induced diabetic rat model. One­day­old Wistar rats were injected with STZ (100 mg/kg), followed by intraperitoneal administration of betatrophin to the STZ­injected rats for 6 days. Plasma glucose and body weight were monitored. On days 4 and 7, expression levels of pancreatic duodenal homeobox gene­1 (PDX­1), the Bax/B­cell lymphoma­2 (Bcl­2) ratio and plasma insulin were assessed, and the ß­cell proliferation rate was determined. Pancreatic islet area and number were determined at 10 weeks. It was found that betatrophin treatment alleviated STZ­induced hyperglycemia, elevated pancreatic expression levels of Bcl­2, PDX­1, plasma insulin levels and the ß­cell proliferation rate on days 4 and 7. Long­term betatrophin treatment improved glucose tolerance, associated with improved plasma insulin levels and ß­cell mass. These results suggest that early administration of betatrophin promotes ß­cell proliferation in STZ­induced diabetic neonates and prevents the development of diabetes in adults.

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