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1.
PLoS One ; 15(1): e0227242, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31918433

RESUMO

Both microwave (MW) ablation and radiofrequency (RF) ablation are widely used for hepatocellular carcinoma (HCC) treatments in clinic. However, it is still unclear if ablative methods could influence the recurrence-free survival (RFS) and overall survival (OS) of HCC patients. Therefore, we carried out this multi-center retrospective cohort study to investigate the differences of recurrence-free survival (RFS) and overall survival (OS) between MW ablation and RF ablation by survival analysis. From January 2014 to December 2016, patients who received thermal ablation surgery for HCC treatment were screened. Finally, 452 patients met the eligibility criteria and finished the follow-up. Univariable and multivariable regression analyses were used to identify independent predictive factors of the RFS and OS. Also, propensity score matching (PSM) was used to balance the bias between two groups. Finally, we found that before the PSM, the univariable and multivariable regression analyses revealed that there were no significant differences on the RFS between two groups. Same results were obtained for the OS. After PSM, 115 pairs of patients were created, and both the univariable and multivariable regression analyses suggested that there were still no significant differences on the RFS between two groups. Same results were obtained for the OS. In conclusion, our present study showed that there were no significant differences between MW ablation and RF ablation for HCC patients on the RFS or OS.

2.
Huan Jing Ke Xue ; 41(1): 262-272, 2020 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854927

RESUMO

Water is an important pathway for human exposure to heavy metals. Accurate assessment of the health risks that are related to exposure to heavy metals in drinking and household water are required for the preparation of targeted health risk prevention measures. This study explores and identifies the health risks related to exposure to heavy metals via drinking and household water pathways in Xigu District, Lanzhou, northwestern China, using household water samples and survey data obtained during July-September 2015 (wet season) and December 2015-January 2016 (dry season). During each period, drinking water and household water that were available for use by children aged 0-5 and 6-17 years were sampled and a questionnaire on water-related behavior patterns was completed for each household. Cd, Cr, Pb, and As concentrations were analyzed in all water samples, and were used along with water-related exposure factors from the questionnaires to estimate exposure doses and associated health risks using models recommended by the United States Environmental Protection Agency (US EPA). The results showed that the concentrations of Cd, Cr, Pb, and As in both drinking and household water samples did not exceed the relative thresholds defined in China's national water quality standards. The concentrations of heavy metals in household water were more affected by seasonal factors than of those of drinking water. The non-cancer and cancer risks were in the ranges of 2.82×10-8-2.43×10-2 and 7.55×10-9-3.62×10-5, respectively, which are within acceptable levels, although the non-cancer and cancer risks from drinking water were both higher than of those determined for household water. Furthermore, the non-cancer and cancer risks from household water for children aged 0-5 years were lower than of those for children aged 6-17 years in each period. However, the cancer risk from drinking water for children aged 0-5 years was lower than of that for children aged 6-17 years, whereas the reverse was found for non-cancer risks. This study indicates that Cd, Cr, Pb, and As in drinking and household water did not pose significant detrimental effects to human health, and that the refined exposure assessment used could reduce uncertainties in health risk assessments.


Assuntos
Água Potável/química , Monitoramento Ambiental , Metais Pesados/análise , Poluentes Químicos da Água/análise , Adolescente , Criança , Pré-Escolar , China , Humanos , Lactente , Recém-Nascido , Medição de Risco , Estações do Ano
3.
Anal Chim Acta ; 1095: 185-196, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31864621

RESUMO

A multiple turn-on fluorophore (FHCS), combining fluorescein, hydrazone, cyanuric chloride and salicylaldehyde chromone into a molecule, was identified and developed based on density functional theoretical calculation. It was expected that FHCS could express exclusive fluorescent signals and improved Stokes shifts when chelating Al3+ or Zn2+. After it was synthesized and characterized in detail, it was noted that FHCS could turn-on fluorescently discriminate trace Al3+ and Zn2+ under the optimized conditions, i.e., from no-fluorescence to strong blue fluorescence for Al3+ and to green fluorescence for Zn2+ with low detection limits of 5.37 × 10-8 M and 7.90 × 10-8 M respectively. Owing to its low toxicity, FHCS was successfully applied for quantitative determination of Al3+ and Zn2+ in natural aqueous samples and toxicity evaluation of Al3+ and Zn2+ in living cells and bio-tissues with excellent linear relationships. The action mechanisms for FHCS with Al3+ and Zn2+ were confirmed to form stable 5-member-co-6-member condensed rings between Al3+/Zn2+ and N/O atoms in FHCS by both theoretic and experimental methods, which resulted in turn-on fluorescence with different dipolar moments and improved Stokes shifts.

4.
Metabolism ; : 154046, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31837300

RESUMO

BACKGROUND: Hepatic ER stress is a risk factor of insulin resistance and type 2 diabetes. X-box binding protein 1 spliced (XBP1s), a transcription factor, plays a key role in ameliorating insulin resistance and maintaining glucose homeostasis. Unfortunately, the short half-life of the protein dampens its clinical application, and the specific site of lysine residue that could be ubiquitinated and involved in the degradation of XBP1s remains elusive. METHODS AND RESULTS: Here, we identified K60 and K77 on XBP1s as two pivotal ubiquitin sites required for its proteasome-dependent degradation. We also constructed a double mutant form of XBP1s (K60/77R) and found that it showed higher capacity in resisting against ubiquitin-mediated protein degradation, increasing nuclear translocation, enhancing transcriptional activity, suppressing ER stress and promoting Foxo1 degradation, compared to that of wild type XBP1s (WT). Consistently, overexpression of the K60/77R XBP1s mutant in DIO mice increased the ability to reduce ER stress and decrease Foxo1 levels, thus contributed to maintaining glucose homeostasis. CONCLUSION: Our results suggest that delaying the degradation of XBP1s by preventing ubiquitination might provide a strategic approach for reducing ER stress as an anti-diabetes therapy.

5.
Dalton Trans ; 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31830161

RESUMO

Cucurbit[10]uril {Q[10]} has the largest portal size and cavity in the series of Q[n] (n = 5-10) molecules. In contrast to its rich host-guest chemistry, its coordination chemistry is underdeveloped with only limited metal ions being investigated so far. In this work, we initiated the study of Q[10] complexes with Th(iv) and U(vi) ions in HCl solutions via a self-assembly approach. The coordination of Th(iv) ions with Q[10] led to the formation of a compound, {Th4(Cl)16(H2O)20(Q[10])}·nH2O (Q[10]-Th), with a unique nano-tubular structure, while U(vi) ions facilitated the formation of a compound, [(UO2)2(Cl)4(H2O)6]·(Q[10])2·HCl·nH2O (Q[10]-U), with a Q[10]-based supramolecular framework structure via intermolecular outer-surface and second-shell interactions. The structural and spectroscopic aspects of the two compounds together with their optical and thermal properties have been investigated. The successful preparation and characterization of the first two Q[10] compounds with Th(iv)/U(vi) ions highlighted the potential for further exploration of Q[10] coordination chemistry with actinide ions.

6.
Diabetol Metab Syndr ; 11: 96, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31788033

RESUMO

Background: To investigate effects of metformin on the regulation of proteins of white adipose tissue (WAT) and brown adipose tissue (BAT) in obesity and explore the underlying mechanisms on energy metabolism. Methods: C57BL/6J mice were fed with normal diet (ND, n = 6) or high-fat diet (HFD, n = 12) for 22 weeks. HFD-induced obese mice were treated with metformin (MET, n = 6). After treatment for 8 weeks, oral glucose tolerance test (OGTT) and hyperinsulinemic-euglycemic clamp were performed to evaluate the improvement of glucose tolerance and insulin sensitivity. Protein expressions of WAT and BAT in mice among ND, HFD, and MET group were identified and quantified with isobaric tag for relative and absolute quantification (iTRAQ) coupled with 2D LC-MS/MS. The results were analyzed by MASCOT, Scaffold and IPA. Results: The glucose infusion rate in MET group was increased significantly compared with HFD group. We identified 4388 and 3486 proteins in WAT and BAT, respectively. As compared MET to HFD, differential expressed proteins in WAT and BAT were mainly assigned to the pathways of EIF2 signaling and mitochondrial dysfunction, respectively. In the pathways, CPT1a in WAT, CPT1b and CPT2 in BAT were down-regulated by metformin significantly. Conclusions: Metformin improved the body weight and insulin sensitivity of obese mice. Meanwhile, metformin might ameliorate endoplasmic reticulum stress in WAT, and affect fatty acid metabolism in WAT and BAT. CPT1 might be a potential target of metformin in WAT and BAT.

7.
J Virol Methods ; 276: 113793, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31794781

RESUMO

Dengue fever is a highly endemic arthropod-borne viral disease in the tropical and sub-tropical countries and is rapidly becoming a global threaten. Diagnosis has been conducted by either traditional serological methods or molecular biological techniques. However, these methods are either labor-intensive, time-consuming or with multiple steps, which are not suitable for high throughput detection of large quantity of samples. In the current study, a novel, rapid, no-wash one-step amplified luminescent proximity homogenous assay-linked immunosorbent assay (AlphaLISA) was developed and optimized for the diagnosis of dengue fever through the detection of dengue virus non-structural protein 1 (NS1). The linear range of the assay was determined to be 60,000 pg/mL to 200 pg/mL, with a lower detection limit of 127.45 pg/mL for NS1 protein. The precision of the assay was 8.24 % and 4.93 % for the high and low concentration. Clinical evaluation indicated that the sensitivity and specificity of the assay was 91.49 % and 81.54 %, respectively. This novel, rapid, no-wash one-step AlphaLISA assay is convenient and sensitive, which could be a good alternative for the screening of dengue fever in a high throughput format.

8.
Oncol Lett ; 18(6): 6554-6562, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31807174

RESUMO

Epithelial-to-mesenchymal transition (EMT) is an essential phenotypic conversion involved in cancer progression. Epidermal growth factor (EGF) and transforming growth factor (TGF)-ß1 are potent inducers of the EMT. Tanshinone IIA (Tan IIA) is a phenanthrenequinone extracted from the root of Salvia miltiorrhiza Bunge, and its anticancer activity has been demonstrated in numerous studies. However, the mechanisms of action underlying Tan IIA in EGF- and TGF-ß1-induced EMT in HepG2 cells remain unknown. Multiple assays were utilized in the present study, including colony formation, wound healing, Transwell invasion, immunofluorescence staining and western blotting, in order to assess the influence of Tan IIA on HepG2 cells induced by 20 ng/ml EGF and 10 ng/ml TGF-ß1. The present study reported that Tan IIA treatment decreased EGF- and TGF-ß1-enhanced cell colony numbers, migration and invasion, and inhibited EGF- and TGF-ß1-induced decreases in the expression levels of E-cadherin, and increases in the expression levels of matrix metalloproteinase-2, N-cadherin, vimentin and Snail. In addition, it was observed that Tan IIA decreased the expression levels of phosphorylated (p)-Akt and p-ERK1/2 induced by EGF and TGF-ß1. Furthermore, western blot analysis confirmed that blocking the function of PI3K/Akt and ERK with LY294002 and U0126 resulted in upregulation of E-cadherin expression, and downregulation of vimentin and Snail expression in EGF- and TGF-ß1-treated HepG2 cells. In conclusion, to the best of our knowledge, the results of the present study are the first to indicate that Tan IIA may suppress EGF- and TGF-ß1-induced EMT in HepG2 cells by deactivating the PI3K/Akt/ERK pathway.

9.
J Hazard Mater ; : 121831, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31843414

RESUMO

An innovative strategy of adjusting the molecular polarity of organics is applied for multifunctional simultaneous ions detection. It involved the use of 4-bromo-2-hydroxyben Rhodamine B hydrazide (RHBr) as a colorimetric and fluorescent multifunctional chemosensor. Briefly, it was designed and prepared via integrating 4-bromo-2-hydroxybenzaldehyde with Rhodamine B hydrazide, and Rhodamine B as fluorophore group, CO, -CHN and -OH groups as reaction site, Br atom as electro n-withdrawing group. On the basis of theoretical calculation under Gaussian 09 software suit, RHBr could exclusively recognize Cu2+, Al3+ and Ca2+. This was also experimentally confirmed by the different turn-on colorimetric and fluorescent signals. For example the selective detection of Cu2+ ion in DMSO/H2O (1/1 = v/v, 10.0 mM HEPES pH 7.0) with the "naked-eye" when the color changed from colorless to pink, Al3+ with "turn-on" strong orange-red fluorescence and Ca2+ with strong green fluorescence in EtOH/H2O (v/v = 95/5). Under the optimized conditions, all the ions could be detected at a very low concentrations (1.7 × 10-7 M, 1.0 × 10-8 M, 2.8 × 10-7 M for Cu2+, Al3+, and Ca2+, respectively). In addition, the "in situ" formed RHBr-Al3+ was used to recognize l-phenylalanine (LPA) with a "turn-off" fluorescence ranging from 0.03-10.0 µM with the low detection concetration of 3.0 × 10-7 M. The sensing mechanisms of RHBr toward three metal ions and the ensemble RHBr-Al3+ toward the l-phenylalanine (LPA) were further investigated in detail. Practical application experiments further proved that RHBr had good cell permeability and could be utilized to detect Al3+ and Ca2+, and the complexes of RHBr-Al3+ could be applied to detect l-phenylalanine (LPA) in the living cells and zebrafishes, respectively.

10.
Chem Soc Rev ; 48(23): 5564-5595, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31670726

RESUMO

The design and applications of some inorganic two-dimensional (2D) nanomaterials such as graphene, graphyne, and borophene have been widely studied in recent years. Meanwhile, it has been noticed that self-assembling two-dimensional organic biomaterials (2DOBMs) including films, membranes, nanosheets, nanoribbons, grids, arrays, and lattices based on various biomolecules also exhibited promising structures, functions, and applications. The in-depth studies on the self-assembly formation, structural and functional tailoring of 2DOBMs open new avenues for the next generation of novel nanomaterials with adjustable structure and functions, which would further promote the applications of 2DOBMs in materials science, nanodevices, energy and environmental science, biomedicine, tissue engineering, and analytical science. In this review, we summarize important information on the basic principles to fabricate self-assembling 2DOBMs based on peptides, proteins, DNA, RNA, viruses, and other biopolymers. The potential strategies and techniques for tailoring and controlling the structures and functions of 2DOBMs are presented and discussed further. The function-specific biomedical applications of 2DOBMs in biosensors, biomimetic mineralization, cell growth, drug/gene delivery, and bioimaging are also highlighted.


Assuntos
Materiais Biocompatíveis/química , Animais , Técnicas Biossensoriais/métodos , DNA/química , Portadores de Fármacos/química , Nanoestruturas/química , Imagem Óptica , Polímeros/química , Proteínas/química , Engenharia Tecidual
11.
Zootaxa ; 4624(4): zootaxa.4624.4.7, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31716201

RESUMO

A new species of the microhylid frog genus Microhyla is described from the Fanjing Mountain of Guizhou Province, China. Phylogenetic analyses based on DNA sequences of the the mitochondrial 12S rRNA, 16S rRNA and COI genes supported the new species as an independent lineage, closely related to M. beilunensis, M. mixtura and M. okinavensis. The uncorrected genetic distance on 16S rRNA gene between the new species and its closest congeners M. beilunensis, M. mixtura and M. okinavensis are 3.5%, 4.6% and 4.6% respectively. The new species is distinguished from its congeners by a combination of the following morphological characters: (1) body of medium size (SVL 19.0-22.7 mm in males and 22.5-23.0 mm in females); (2) disk and dorsal median longitudinal groove on finger tips absent; (3) toe with rudimentary webbing at base; (4) disk with dorsal median longitudinal groove present at toe tips except for the toe I; (5) two metatarsal tubercles on palm; (6) tibiotarsal articulation reaching the level between eye to nostril when leg stretched forward; (7) a distinct V-shaped white stripe on the upper midsection. The new species is known only from the type locality, and thus the finding of it has contributed to the endemic species diversity of China. It is needed to take strategy to protect the species and habitats due to the increased threats of environmental changes.


Assuntos
Anuros , Animais , Tamanho Corporal , China , Feminino , Masculino , Filogenia , RNA Ribossômico 16S
12.
Biol Pharm Bull ; 42(11): 1789-1798, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31685763

RESUMO

Autophagy plays key roles in the development of acute pancreatitis (AP) and the regulation of impaired autophagy has therapeutic potential. The objective of the present study was to investigate whether pharmacological inhibition of autophagy could ameliorate AP in mice and examine the underlying mechanisms. In current study, by imaging-based high-throughput screening, a novel spautin-1 derivative spautin-A41 was identified as a potent autophagy inhibitor. Mice treated with spautin-A41 were resistant to the cerulein-induced elevation of serum pancreatic enzyme activities and pancreatic apoptosis. Mechanistically, spautin-A41 effectively reduced the expression levels of Class III phosphatidylinositol 3 (PI3) kinase complexes and subsequently ameliorated pancreatitis by inhibiting the formation of autophagosome. Therefore, pharmacological inhibition of autophagy by spautin-A41 may serve as new target for treating or lessening the severity of AP.

13.
Mol Cell ; 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31677973

RESUMO

Interphase chromatin is hierarchically organized into higher-order architectures that are essential for gene functions, yet the biomolecules that regulate these 3D architectures remain poorly understood. Here, we show that scaffold attachment factor B (SAFB), a nuclear matrix (NM)-associated protein with RNA-binding functions, modulates chromatin condensation and stabilizes heterochromatin foci in mouse cells. SAFB interacts via its R/G-rich region with heterochromatin-associated repeat transcripts such as major satellite RNAs, which promote the phase separation driven by SAFB. Depletion of SAFB leads to changes in 3D genome organization, including an increase in interchromosomal interactions adjacent to pericentromeric heterochromatin and a decrease in genomic compartmentalization, which could result from the decondensation of pericentromeric heterochromatin. Collectively, we reveal the integrated roles of NM-associated proteins and repeat RNAs in the 3D organization of heterochromatin, which may shed light on the molecular mechanisms of nuclear architecture organization.

14.
Medicine (Baltimore) ; 98(47): e17894, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31764785

RESUMO

Peripherally inserted central catheter (PICC) is often applied in chemotherapy patients and commonly causes upper extremity venous thrombosis (UEVT), which should be prevented.To assess the preventive effects of the anticoagulants rivaroxaban and low molecular weight heparin (LMWH) on UEVT in patients receiving chemotherapy through PICCs.A total of 423 chemotherapy patients with continuous PICC use between January 2014 and June 2015 at the Oncology Department of Dongying People's Hospital were divided into 3 groups: rivaroxaban (10 mg/day, orally), LMWH (Enoxaparine, 4000 anti-Xa IU/day, subcutaneous injection), and control (no anticoagulant). UEVT incidence and other complications during PICC use were observed and recorded.The rivaroxaban, LMWH, and control groups included 138 (79 males; 54.9 ±â€Š11.0 years), 144 (76 males; 56.0 ±â€Š10.9 years), and 141 (71 males; 53.3 ±â€Š10.9 years) patients, (P = .402 and P = .623 for age and sex respectively). There were no differences in cancer location (P = .628), PICC implantation site (P > .05), body mass index (BMI) (P = .434), blood pressure (all P > .05), blood lipids (5 laboratory parameters included, all P > .5), smoking (P = .138), history of lower limb venous thrombosis (P = .082), and 10 other associated comorbidities (all P > .5). Twenty-nine patients withdrew from the study (5 from the rivaroxaban, 12 from the LMWH, and 12 from the control groups, respectively), and 394 patients were analyzed. There were significant differences in the rivaroxaban group and the LMWH group compared to the control group (P = .010 and P = .009, respectively), but no significant difference was observed between the rivaroxaban group and the LMWH group (P = .743).Anticoagulants such as rivaroxaban and LMWH may reduce the incidence of PICC-related UEVT in patients receiving chemotherapy.

15.
Sci Rep ; 9(1): 15165, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31619726

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

16.
Phytopathology ; : PHYTO07190253FI, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31600117

RESUMO

The genus Dichorhavirus contains viruses with bipartite, negative-sense, single-stranded RNA genomes that are transmitted by flat mites to hosts that include orchids, coffee, the genus Clerodendrum, and citrus. A dichorhavirus infecting citrus in Mexico is classified as a citrus strain of orchid fleck virus (OFV-Cit). We previously used RNA sequencing technologies on OFV-Cit samples from Mexico to develop an OFV-Cit-specific reverse transcription PCR (RT-PCR) assay. During assay validation, OFV-Cit-specific RT-PCR failed to produce an amplicon from some samples with clear symptoms of OFV-Cit. Characterization of this virus revealed that dichorhavirus-like particles were found in the nucleus. High-throughput sequencing of small RNAs from these citrus plants revealed a novel citrus strain of OFV, OFV-Cit2. Sequence comparisons with known orchid and citrus strains of OFV showed variation in the protein products encoded by genome segment 1 (RNA1). Strains of OFV clustered together based on host of origin, whether orchid or citrus, and were clearly separated from other dichorhaviruses described from infected citrus in Brazil. The variation in RNA1 between the original (now OFV-Cit1) and the new (OFV-Cit2) strain was not observed with genome segment 2 (RNA2), but instead, a common RNA2 molecule was shared among strains of OFV-Cit1 and -Cit2, a situation strikingly similar to OFV infecting orchids. We also collected mites at the affected groves, identified them as Brevipalpus californicus sensu stricto, and confirmed that they were infected by OFV-Cit1 or with both OFV-Cit1 and -Cit2. OFV-Cit1 and -Cit2 have coexisted at the same site in Toliman, Queretaro, Mexico since 2012. OFV strain-specific diagnostic tests were developed.

17.
Cell Death Differ ; 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31645676

RESUMO

Microtubule-targeting agents (MTAs) are a class of most widely used chemotherapeutics and their mechanism of action has long been assumed to be mitotic arrest of rapidly dividing tumor cells. In contrast to such notion, here we show-in many cancer cell types-MTAs function by triggering membrane TNF (memTNF)-mediated cancer-cell-to-cancer-cell killing, which differs greatly from other non-MTA cell-cycle-arresting agents. The killing is through programmed cell death (PCD), either in way of necroptosis when RIP3 kinase is expressed, or of apoptosis in its absence. Mechanistically, MTAs induce memTNF transcription via the JNK-cJun signaling pathway. With respect to chemotherapy regimens, our results establish that memTNF-mediated killing is significantly augmented by IAP antagonists (Smac mimetics) in a broad spectrum of cancer types, and with their effects most prominently manifested in patient-derived xenograft (PDX) models in which cell-cell contacts are highly reminiscent of human tumors. Therefore, our finding indicates that memTNF can serve as a marker for patient responsiveness, and Smac mimetics will be effective adjuvants for MTA chemotherapeutics. The present study reframes our fundamental biochemical understanding of how MTAs take advantage of the natural tight contact of tumor cells and utilize memTNF-mediated death signaling to induce the entire tumor regression.

18.
Nanomaterials (Basel) ; 9(10)2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31658682

RESUMO

Hydroxyapatite (HA) has been widely used in fields of materials science, tissue engineering, biomedicine, energy and environmental science, and analytical science due to its simple preparation, low-cost, and high biocompatibility. To overcome the weak mechanical properties of pure HA, various reinforcing materials were incorporated with HA to form high-performance composite materials. Due to the unique structural, biological, electrical, mechanical, thermal, and optical properties, graphene has exhibited great potentials for supporting the biomimetic synthesis of HA. In this review, we present recent advance in the biomimetic synthesis of HA on graphene supports for biomedical applications. More focuses on the biomimetic synthesis methods of HA and HA on graphene supports, as well as the biomedical applications of biomimetic graphene-HA nanohybrids in drug delivery, cell growth, bone regeneration, biosensors, and antibacterial test are performed. We believe that this review is state-of-the-art, and it will be valuable for readers to understand the biomimetic synthesis mechanisms of HA and other bioactive minerals, at the same time it can inspire the design and synthesis of graphene-based novel nanomaterials for advanced applications.

19.
Molecules ; 24(19)2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31581746

RESUMO

A series of fluorescent coumarin derivatives 2a-e were systematically designed, synthesized and studied for their Cu2+ sensing performance in aqueous media. The sensitivities and selectivities of the on-to-off fluorescent Cu2+ sensing signal were in direct correlation with the relative arrangements of the heteroatoms within the coordinating moieties of these coumarins. Probes 2b and 2d exhibited Cu2+ concentration dependent and selective fluorescence quenching, with linear ranges of 0-80 µM and 0-10 µM, and limits of detection of 0.14 µM and 0.38 µM, respectively. Structural changes of 2b upon Cu2+ coordination were followed by fluorescence titration, attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), mass spectrometry, and single crystal X-ray diffraction on the isolated Cu2+-coumarin complex. The results revealed a 1:1 stoichiometry between 2b and Cu2+, and that the essential structural features for Cu2+-selective coordination are the coumarin C=O and a three-bond distance between the amide NH and heterocyclic N. Probe 2b was also used to determine copper (II) levels in aqueous soil extracts, with recovery rates over 80% when compared to the standard soil analysis method: inductively coupled plasma-mass spectrometry (ICP-MS).

20.
Mater Sci Eng C Mater Biol Appl ; 104: 109891, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31500035

RESUMO

Currently, a lot of efforts have been applied to diagnosis and treat tumors through the fabrication of highly-efficient and multi-functional nanomaterials. Superior to other methods, photothermal therapy (PTT) has been demonstrated as a noninvasive, controllable, and targeted strategy to eliminate tumor cells. The use of functional biomedical and bioactive nanomaterials can enhance the photothermal performances and meanwhile integrate with favorable functions, by taking into account their risk assessments. In this review, novel engineered photothermal nanomaterials, such as noble metal-, carbon-, semiconductor-, and organic molecule-based PTT agents, as well as their targeted biomedical applications were summarized and discussed comprehensively. Particularly, the latest advances of not only the conventional nanomaterials, but also the newly-discovered alternatives, like Au-Ag, graphdiyne, and selenides, were introduced. Besides the benefits, the risks and other implications of novel PTT agents were recorded and evaluated. Moreover, the potential applications of nanomaterials in targeted and multi-functional PTT treatments, which served as foundations and directions for future PTT approaches developments, were stated. Depending on the urgency and boosting demands for tumor treatments, novel engineering advancements of techniques, not limited to PTT and nanomaterials, are prerequisites in the history of medical development.

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