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1.
Talanta ; 207: 120285, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31594625

RESUMO

Detection of microRNAs (miRNAs) in cells improves our understanding of their physiological functions and facilitates exploration of their roles diseases. The toehold-mediated strand displacement reaction initiates rolling circle amplification (RCA) to achieve signal amplification of the specific miRNA; This process is named as toehold-initiated RCA (TIRCA). The product of TIRCA was ligated to two DNA probes, which were modified with 6-carboxyfluorescein and carboxytetramethylrhodamine, respectively. Qualitative detection of miRNAs was successfully achieved by combining the fluorescence aggregation enhancement effect with fluorescence resonance energy transfer generated by the proximity of the two fluorescent dyes. Thus, this approach helps us analyze the roles of miRNAs in human disease more accurately.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31689551

RESUMO

In this study, we identified a fish-specific Toll-like receptor (TLR) in Pelteobagrus fulvidraco, an economically important freshwater fish in China. This TLR, PfTLR26, was shown to be encoded by a 3084 bp open reading frame (ORF), producing a polypeptide 1027 amino acids in length. The PfTLR26 protein contains a signal peptide, eight leucine-rich repeat (LRR) domains, two LRR_TYP domains in the extracellular region, and a Toll/interleukin (IL)-1 receptor (TIR) domain in the cytoplasmic region, consistent with the characteristic TLR domain architecture. This predicted 117.1 kDa protein was highly homologous to those of other fish, with phylogenetic analysis revealing the closest relation to TLR26 of Ictalurus punctatus. Real-time quantitative reverse transcription-PCR (qRT-PCR) analysis showed that the PfTLR26 gene was expressed in all tissues tested, with the highest expression levels seen in the head kidney and blood, and the lowest seen in muscle. PfTLR26 exhibited significant upregulation in liver, spleen, head kidney, and blood at different time points following challenge with the common TLR agonists lipopolysaccharide (LPS) and polyriboinosinic polyribocytidylic acid (Poly I:C). Taken together, these results suggest that PfTLR26 may be an important component of the P. fulvidraco innate immune system, participating in the transduction of TLR signaling under pathogen stimulation.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31714050

RESUMO

High recurrence and metastasis rates are the major causes of the high mortality of hepatocellular carcinoma (HCC). Circulating tumor cells (CTCs) disseminating into the bloodstream plays an essential role in cancer metastasis. However, since HCC-CTCs are extremely rare, limitations of current detection methods impede accurate discerning HCC-CTCs under complicate biological context. Here, a dual-targeting functionalized rGO film (DTFGF) for specific identifying HCC-CTCs was created via coinstantaneous targeting epithelial cell adhesion molecule (EpCAM) and HCC cell-specific asialoglycoprotein receptor (ASGPR). Anti-EpCAM antibodies and galactose-rhodamine-polyacrylamide nanoparticles (Gal-Rh-PAA NPs) specifically recognizing ASGPR are modified on the surface of a graphene film that quench the rhodamine fluorescence. HCC-CTCs can be captured by anti-EpCAM antibody and endocytose Gal-Rh-PAA NPs, recovering the rhodamine fluorescence. Profiting from accuracy of dual-targeting, less handling steps and high resolution of fluorescence imaging, a simple, rapid and low-cost HCC-CTC enumeration method is established with excellent sensitivity and selectivity than conventional methods. Using DTFGFs, as low as 5 HCC-CTCs were detected in a 1 mL blood sample. Further results revealed that larger HCC-CTCs quantities indicate more advanced stages of HCC in patients. Overall, this work holds great promise for the early diagnosis, prognosis and therapeutic evaluation of HCC.

4.
Hematol Oncol ; 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31701557

RESUMO

Immortalized cell lines are useful for deciphering the pathogenesis of acute leukemia and developing novel therapeutic agents against this malignancy. In this study, a new human myeloid leukemia cell line YBT-5 was established. After more than 1-year cultivation from the bone marrow of a patient with acute monocytic leukemia, YBT cell line was established. Then a subclone, YBT-5, was isolated from YBT using single cell sorting. Morphological and cytogenetical characterizations of the YBT-5 cell line were determined by cytochemical staining, flow cytometry analysis, and karyotype analysis. Molecular features were identified by transcriptomic analysis and reverse transcription-polymerase chain reaction. To establish a tumor model, 5 × 106 YBT-5 cells were injected subcutaneously in nonobese diabetic/severe combined immune-deficiency (NOD/SCID) mice. DOT1L has been proposed as a potential therapeutic target for KMT2A-related leukemia; therefore, to explore the potential application of this new cell line, its sensitivity to a specific DOT1L inhibitor, EPZ004777 was measured ex vivo. The growth of YBT-5 does not depend on granulocyte-macrophage colony-stimulating factor. Cytochemical staining showed that α-naphthyl acetate esterase staining was positive and partially inhibited by sodium fluoride, while peroxidase staining was negative. Flow cytometry analysis of YBT-5 cells showed positive myeloid and monocytic markers. Karyotype analysis of YBT-5 showed 48,XY,+8,+8. The breakpoints between KMT2A exon 10 and exon 11 (KMT2A exon 10/11) and MLLT3 exon 5 and exon 6 (MLLT3 exon 5/6) were identified, which was different from all known breakpoint locations, and a novel fusion transcript KMT2A exon 10/MLLT3 exon 6 was formed. A tumor model was established successfully in NOD/SCID mice. EPZ004777 could inhibit the proliferation and induce the differentiation of YBT-5 cells. Therefore, a new acute monocytic leukemia cell line with clear biological and molecular features was established and may be used in the research and development of new agents targeting KMT2A-associated leukemia.

5.
J Vis Exp ; (152)2019 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-31710030

RESUMO

Manual vascular reconstruction training is essential for a beginner surgeon. However, an optimal training system for vascular reconstruction in vitro has yet to be developed. In this study, we introduce an in vitro training and testing system using a magnetic anchoring technique with which a trainee can practice manual vascular reconstruction individually. Additionally, this system can also be used to test the quality of the reconstruction. The described system includes a vascular reconstruction training machine, magnetic tractors, and a magnetic suture puller. In this manuscript, we detail an end-to-end vein anastomosis using porcine right and left iliac veins. To identify the potential damage caused by a magnetic suture puller on the suture, we created three groups with six segments of 4-0 polypropylene sutures each: a control group with no intervention on the polypropylene suture, a group in which the polypropylene suture is manually pulled with sterile gloves 20x, and a magnetic puller group in which the magnetic puller pulled the polypropylene suture 20x. These groups were tested by light microscopy and breaking strength tests, and the effect of reconstruction was assessed. In the light microscopy test, the control group was less likely to be damaged (p < 0.05) and the number of damaged points of the manual group and magnetic puller group were similar (p > 0.05). The results of the breaking strength test were compared across groups and no significant difference was observed (p > 0.05). The end-to-end anastomosis of the porcine iliac veins was successfully performed using this training system, and the reconstructed veins could undergo 2.0 kPa perfusion pressure. Using this training and testing system the trainee can practice manual vascular reconstruction in vitro individually with the aid of magnetic tractors and a magnetic suture puller, and the quality of the reconstruction can be tested.

6.
Brain Behav ; : e01438, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31638334

RESUMO

AIM: The effectiveness of neuroprotective agents is still unclear. Here we analyzed the clinical outcomes of acute ischemic stroke (AIS) patients treated with human urinary kallidinogenase (HUK) or edaravone (Eda) combined with butylphthalide (NBP). METHODS: From January 2016 to December 2017, a total of 165 AIS patients were enrolled in this open-label, randomized controlled clinical study. Patients were randomly allocated into HUK group and Eda group in a ratio of 2:1. All the patients received basic treatments and NBP (200 mg p.o. qid) while HUK group received 0.15 PNA unit of HUK injection (ivgtt. qd) and Eda group received 30 mg Eda (ivgtt. bid) for 14 consecutive days. Independency rate [12-month modified Rankin Scale (mRS) score ≤ 1] and related factors were compared between the two groups. RESULTS: Twelve-month mRS score of the HUK group (1, IQR 0~1) was significantly lower compared with Eda group (2, IQR 1~3, p < .0001). The HUK treatment achieved an independency rate of 79.1% while the Eda treatment only had 45.3% (p < .0001). Further binary logistic regression showed that recurrent stroke (RR: 0.1, 95% CI: 0.0~0.1, p = .038) and HUK treatment (RR: 4.2, 95% CI: 1.1~16.5, p = .041) could significantly affect patients' 12-month outcomes. CONCLUSION: Human urinary kallidinogenase combined with NBP can enhance AIS patients' long-term independency rate, and the effectiveness of HUK combined therapy is better than Eda.

7.
Chem Asian J ; 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31651104

RESUMO

The efficient chemical conversion of carbon dioxide (CO 2 ) into value-added fine chemicals is an intriguing but challenging route in sustainable chemistry. Herein, hollow structured bimetallic zeolitic imidazole framework composed of Zn and Co as metal centers (H-ZnCo-ZIF) has been successfully prepared via a post-synthetic strategy based on controllable chemical-etching of the preformed solid ZnCo-ZIF in tannic acid. The creation of hollow cavities inside each monocrystalline ZIFs could be achieved without destroying the intrinsic frameworks, as characterized by field-emission scanning electron microscopy, transmission electron microscope, and X-ray diffraction technologies. The as-synthesized H-ZnCo-ZIF exhibited remarkable catalytic activity in the cycloaddition of CO 2 with epoxides to the corresponding cyclic carbonates, outperforming the solid ZnCo-ZIF analogue due to the improved mass transfer originated from the hollow structure. More importantly, due to stabilization of metal centers in ZIF framework by tannic acid shell, H-ZnCo-ZIF exhibited good recyclability and no activity loss could be observed in six runs. The present study provides a simple and effective strategy to enhance the catalytic performance of ZIFs by creating hollow structure via chemical-etching.

8.
Org Lett ; 21(22): 8934-8937, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31664838

RESUMO

A highly efficient rongalite-mediated three-component radical annulation reaction to furnish fully substituted pyrazoles from aryldiazonium salts and α,ß-unsaturated aldehydes or ketones under metal- and oxidant-free conditions at room temperature has been developed. In this transformation, aryldiazonium salts served as the precursor of both the aryl and aryl hydrazine units. Mechanistic investigations indicated that rongalite could act as a radical initiator and reducing reagent simultaneously in the reaction.

9.
Anal Chem ; 91(21): 14133-14140, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31566968

RESUMO

Circulating tumor cell (CTC) analysis has been approved for cancer diagnosis and monitoring. However, efficient sorting and high-through phenotypic counting of CTCs from peripheral blood is still a challenge. In this manuscript, we propose an optofluidic flow cytometer (OFCM), which integrates a multistage microfluidic chip and a four-color fluorescence detection system. The OFCM can automatically complete CTC separation, 3D focusing in the microchannel, single-cell phenotypic analysis, and counting at 1.2 mL of whole blood/hour. A high recovery greater than 95% was obtained. Using the OFCM, we analyzed the epithelial-to-mesenchymal transition (EMT) phenotype of CTCs in patients with breast cancer and patients with nonsmall cell lung cancer, which proved that the OFCM is adaptable for phenotypic counting of various CTCs based on the fluorescence labeling of varied biomarkers. We believe that this OFCM will provide a convenient and efficient device for clinical liquid biopsy of tumors.

10.
J Mater Chem B ; 7(43): 6822-6827, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31608921

RESUMO

Identifying cancer at the cellular level during an early stage offers the hope of greatly improved outcomes for cancer patients. As potential cancer biomarkers, nitroreductase (NTR) and human quinine oxidoreductase 1 (hNQO1) are overexpressed in many type of cancer cells. Simultaneous detection of these two biomarkers would benefit diagnostic precision in related cancers without yielding false positive results. Herein, based on a dye generated in situ strategy, a dual-enzyme-responsive probe, CNN, was rationally designed and synthesized by installing p-nitrobenzene and trimethyl-locked quinone propionic acid groups, which are specific for NTR and hNQO1, respectively, into a single fluorophore. This probe is only activated in the presence of both NTR and hNQO1 and produces a large fluorescence response, enabling the detection of both endogenous NTR and hNQO1 activity in living cells. The imaging results indicate that the CNN probe differentiates cancer cells (HeLa, MDA-MB-231 and HepG2 cells) from normal liver HL-7702 cells owing to the existence of relatively high endogenous levels of both biomarkers in these cancer cells.

11.
Biosens Bioelectron ; 147: 111755, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31630032

RESUMO

In cell signal transduction pathways, a series of biochemical reactions and interactions between proteins guarantee physiological responses indicating cell functionality. However, there are a variety of upstream and downstream signal molecules in these pathways with multiple levels of cross-regulation, making it difficult to sequential visualize their relationships in living organisms in complex environments. To investigate the interrelationships among intracellular signaling pathways, a Au-Se bonded nanoprobe with extraordinary stability and strong anti-interference ability was designed and prepared to monitor the evolution of two kinds of apoptosis biomarkers in real time. Two different peptide chains decorated with two dyes were functionalized on the surface of Au nanoparticles (NPs) via Au-Se bonds. These peptide chains can be respectively cleaved by upstream cathepsin B proteins and downstream caspase-3 proteins to trigger fluorescence recovery. Moreover, when the living cells were stimulated to induce the apoptotic pathway, cathepsin B and caspase-3 were activated in turn with signals sequentially recovered at 2 and 4 h, respectively. This fluorescent nanoprobe can be used in complicated biological systems to achieve real-time in situ monitoring of the sequential activation of signal molecules in intracellular pathways and provides a novel approach for the future investigation of protein interactions in vivo.

12.
Fish Shellfish Immunol ; 95: 140-150, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31629063

RESUMO

To learn more about red swamp crayfish related genes in response to bacterial infections, we investigated immune-related genes induced by lipopolysaccharide (LPS) in the hepatopancreas using high-throughput sequencing method. In present the study, a total of 55,107 unigenes were identified, with an average length of 678 bp. A total of 2215 differentially expressed genes (DEGs) were found, including 669 up-regulated genes and 1546 down-regulated genes. The result of Gene ontology (GO) analysis revealed that 3017 DEGs were enriched in 19 biological process subcategories, 17 cellular component subcategories and 15 molecular function subcategories. The top 20 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways showed that "ribosome" was the most abundant group, which had 34 DEGs. KEGG enrichment analysis identified several immune response pathways. Real-time quantitative reverse transcription-PCR (qRT-PCR) results exhibited that several immune responsive genes were greatly up-regulated following LPS stimulation as observed in the results of high-throughput sequencing. Overall, this study provides new insight into the immune defense mechanisms of P. clarkii against LPS infection.

13.
Biomaterials ; 225: 119499, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31561087

RESUMO

Hepatic ischemia-reperfusion (IR) injury is dynamically regulated by intertwined superoxide anion (O2-)-peroxynitrite (ONOO-) cascaded molecules. Arginase 1 involves in O2-/ONOO- fluctuations and is strongly connected to IR injury. A few probes have been innovated to measure intracellular O2- or ONOO- by fluorescent imaging separately, but revealing the definite link of O2-, ONOO- and arginase 1 in situ remains unidentified in hepatic IR. Thus, a well-designed dual-color two-photon fluorescence probe (CyCA) was created for the in situ real-time detection of O2--ONOO-. Surprisingly, CyCA exhibited a suitable combination of high specificity, preeminent sensitivity, exclusive mitochondria-targeting and fast-response. On the basis of remarkable advantages, we successfully applied CyCA to visualize endogenous O2- and ONOO- in living cells and mice. The synergistic elevation of mitochondrial O2--ONOO- in IR mice was observed for the first time. Furthermore, three tyrosine nitration-sites in arginase 1 caused by ONOO- were identified in proteomic analysis, which was never reported previously. Attractively, nitro-modified arginase 1 could further promote ONOO- formation, ultimately exacerbating the intracellular redox imbalance and IR injury. These new findings decipher direct molecular links of O2--ONOO--arginase 1, and suggest effective strategies for the prevention and treatment of IR injury.

14.
Nanoscale ; 11(39): 18021-18025, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31560009

RESUMO

A self-assembly of an active tumor-cell-targeted photothermal agent, functionalized with a cyclic Arg-Gly-Asp peptide and ibuprofen, for killing cancer cells and eliciting anti-inflammatory responses was developed. In vitro and in vivo experiments also demonstrated that the photothermal material exhibited low cytotoxicity, good biological compatibility and excellent tumor inhibitory effects.

15.
Org Lett ; 21(18): 7324-7328, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31508967

RESUMO

A novel and efficient aldol reaction of readily available vinyl azides with trifluoromethyl ketones by copper catalysis is developed. The reaction is proposed to go through a nucleophilic trapping of vinyl azides with trifluoromethyl ketones as a trifluoromethyl source, leading to the assembly of diverse trifluoromethylated compounds under mild conditions in satisfactory yield.

16.
Theranostics ; 9(20): 5828-5838, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31534522

RESUMO

Goals: Hepatocellular carcinoma (HCC) has been reported to be the third most common malignant tumor and has the highest rate of mortality. To increase the chemotherapy efficacy of HCC, a drug delivery system featured with desirable active targeting ability, delivery efficiency and immune evasion is in high demand. Methods: We have developed a drug nanocarrier by utilizing a homotypic cancer cell membrane for targeted chemotherapy of HCC. Structurally, the homotypic HepG2 cell membrane was used as the cloak, and a poly (lactic-co-glycolic acid) (PLGA) nanoparticle as the core, resulting in the nanocarrier HepM-PLGA. Results: The HepM-PLGA nanoparticles exhibit excellent targeting ability toward HepG2 cells. Doxorubicin (Dox) carried by HepM-PLGA possesses high delivery efficiency and a remarkable in vitro therapeutic effect. In in vivo experiments, HepM-PLGA delivers Dox directly to the tumor lesion of nude mice, and tumor volume decreases by approximately 90% after treatment. Conclusion: We have developed a drug nanocarrier by utilizing a homotypic cancer cell membrane for targeted chemotherapy of HCC with excellent active targeting ability. This biomimetic platform not only effectively treats HCC but also provides a sound strategy for the treatment of other cancers via changes in the corresponding homotypic cancer cell membrane.

17.
Chem Commun (Camb) ; 55(76): 11426-11429, 2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31482870

RESUMO

Highly regioselective Markovnikov hydrofunctionalization of alkenes was successfully realized via photoredox catalysis by introducing a urea group and fine tuning the hydrogen atom transfer catalysts. The anti-Markovnikov hydroamination of alkenes was also achieved with high yields and stereoselectivities in this work.

18.
Anal Chem ; 91(20): 12874-12881, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31518111

RESUMO

To achieve personalized healthcare, a quick, accurate, and high-throughput method to detect disease biomarkers is essential. In the traditional practice, mass spectrometry is one of the most powerful tools and is widely studied. However, the test of human serum usually requires complicated sample pretreatment, tedious operations, and precise condition control, especially for the detection of enzymes as biomarkers. As butyrylcholinesterase (BuChE) has an indicative significance in detecting degenerative disease, liver injury, and organophosphate poisoning, the quick quantification of BuChE is of vital importance to the clinic. In this paper, we report the design and fabrication of a portable 3D-printed enzyme reactor paper spray cartridge (3D ER-PS) with integrated functions: temperature control, enzyme reaction, analyte transfer, and paper spray ionization. Coupled with mass spectrometry, quantitative testing of BuChE activity in human serum was realized conveniently and accurately. While it only requires very simple sample preparation, the results from current 3D ER-PS approach are well consistent with those obtained using Ellman's method. This 3D ER-PS platform not only provides a novel solution for the liquid biopsy of BuChE in clinics but also contributes to the development of quick and targeted medical approaches for analyzing other types of serum biomarker molecules in the field of disease diagnosis.

20.
Mar Drugs ; 17(9)2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31470583

RESUMO

Penicillum citreonigrum XT20-134 (MCCC 3A00956) is a fungus with cytotoxic activity, derived from deep-sea sediment. Five new compounds, adeninylpyrenocine (1), 2-hydroxyl-3-pyrenocine-thio propanoic acid (2), ozazino-cyclo-(2,3-dihydroxyl-trp-tyr) (3), 5,5-dichloro-1-(3,5-dimethoxyphenyl)-1,4-dihydroxypentan-2-one (4), and 2,3,4-trihydroxybutyl cinnamate (5), together with 19 known compounds (6-24), were isolated from an ethyl acetate (EtOAc) extract of its fermentation. The structures of the new compounds were comprehensively characterized by high-resolution electrospray ionization-mass spectrometry (HR-ESI-MS), 1D and 2D nuclear magnetic resonance (NMR). All isolates were evaluated for their cytotoxic activities. The heteroatom-containing new compounds 2 and 4 showed potent cytotoxicity to the human hepatoma tumor cell Bel7402 with IC50 values of 7.63 ± 1.46, 13.14 ± 1.41 µM and the human fibrosarcoma tumor cell HT1080 with IC50 values of 10.22 ± 1.32, 16.53 ± 1.67 µM, respectively.

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