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1.
Biomaterials ; 228: 119569, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31678845

RESUMO

The current conventional photo-therapeutic agents often show low therapy efficacy because of their single treatment model, the limited penetration depth of excitation light and hypoxia in the tumor microenvironment (TME). Herein, a new type of phthalocyanine manganese (MnPcE4) photosensitizer with strong NIR absorption was designed and fabricated for the first time, and was used to modify pure Bi nanomaterials to obtain an intelligent multifunctional Bi/MnPcE4 nanocomposites. The Mn2+ in the Bi/MnPcE4 nanocomposite could catalyze H2O2 to generate O2, thus helping to overcome TME hypoxia and enhancing the photodynamic therapy (PDT) efficacy. Further, the nanocomposites showed excellent T1-weighted MRI performance. Our novel use of a pure metal Bi core, offers lower toxicity, higher CT imaging performance, and a photothermal therapy (PTT) effect triggered by 808 nm near infrared (NIR) laser. Moreover, in vivo fluorescence imaging (in vivo FL) vividly showed that the nanocomposite rapidly accumulates in tumor sites due to the enhanced permeability and retention (EPR) effect and metabolized in the organs. The presence of Bi enables the use of these nanocomposites as a CT contrast agent, and the Mn content enables them to be used in MRI. This triple imaging ability implies that our nanocomposites have a high potential for use in imaging directed tumor therapy.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31773487

RESUMO

Sogatella furcifera (Horváth), a prominent rice pest in Asia, is a typical R-strategic and highly adaptable insect. Heat shock proteins (Hsps) are highly conserved molecular chaperones regulating responses to various abiotic stresses; however, limited information is available regarding their role in responding to abiotic stress in S. furcifera. This study aimed to investigate the effect of abiotic stresses on the expression of Hsp70 genes in the S. furcifera. Five Hsp70 genes were isolated from S. furcifera, and the expression patterns at different developmental stages and temperatures, upon treatment with different insecticides and ultraviolet A (UV-A) stress, were analyzed. Hsp70 genes were expressed at different developmental stages. Hsp70-2, Hsp70-5, and Hsp70-6 were significantly upregulated upon heat shock at 40 °C for 30 min. Hsp70-3 and Hsp70-4 were significantly upregulated upon heat shock at 30 °C for 30 min. Under UV-A stress, Hsp70-3, Hsp70-4, Hsp70-5, and Hsp70-6 were significantly upregulated. Conversely, Hsp70-2 was significantly downregulated under UV-A stress. The five Hsp70 genes were significantly downregulated in 3rd-instar nymphs on exposure to thiamethoxam, buprofezin, and avermectin at LC10 and LC25 concentrations. Hence, Hsp70 genes significantly contribute to the tolerance of S. furcifera to temperature and UV-A stress; however, they are not involved in the response to insecticides.

3.
Cytokine ; 126: 154878, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31739215

RESUMO

Due to the variable overlap of multiple symptoms, accurate early diagnosis of NK/T-cell lymphoma-associated hemophagocytic syndrome (NK/T-LAHS) is difficult, making the prognosis extremely poor. Hemophagocytic syndrome (HPS) is now diagnosed primarily based on the hemophagocytic lymphohistiocytosis (HLH)-2004 diagnostic criteria, and platelet count is one of the baseline evaluations. However, in our study, the data showed that decreased platelets were not only a clinical feature of HPS but also the key cells that regulate inflammation by releasing α-granules containing upregulated platelet factor 4 (PF4) and downregulated platelet-derived growth factors (PDGFs). Furthermore, we found that angiopoietin-4 (ANG-4), which has significant differential expression, has been less reported, that may affect hematopoiesis and proinflammatory responses and can be used as diagnostic biomarkers together with PF4 and PDGFs.

4.
Nanotechnology ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31751972

RESUMO

By exploiting the storage performance of supercapacitors, iron has the potential to be used as a new anode material. However, unsatisfactory electrical conductivity and poor cycling stability limit the development of energy and power density. Consequently it is the foundation of improving the electrical conductivity and cycling stability of iron materials to obtain the good storage performance. In this work, Ag-modified Fe2O3 nanoparticles on carbon cloth were synthesized as an anode material for supercapacitors. The specific capacitance of the composite material reaches 10.39 F cm-2 (2734.2 F g-1) at a current density of 1 mA cm-2 and remains at 83% of this value after 12000 cycles. The energy density is 379.8 Wh kg-1 at a power density of 131.6 W kg-1 and remains at 123.9 Wh kg-1 at a power density of 2631.6 W kg-1. The electrical conductivity and interfacial effect created between Ag@Fe2O3 is performed by density functional theory calculations. The packaged asymmetric supercapacitor devices have flexibility and can light up ten light-emitting diodes for 2 min 30 s, and an energy density of 60.3 Wh kg-1 can be reached at a power density of 1063.8 W kg-1 and can remain at 16 Wh kg-1 even at a power density of 4255.3 W kg-1.

5.
Biosci Rep ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31746323

RESUMO

AIMS: In this work, we explored the role of corosolic acid (CRA) during pressure overload-induced cardiac hypertrophy. METHODS AND RESULTS: Cardiac hypertrophy was induced in mice by aortic banding. 4 weeks post-surgery, CRA-treated mice developed blunted cardiac hypertrophy, fibrosis, and dysfunction, and showed increased LC3 II and p-AMPK expression. In line with the in vivo studies, CRA also inhibited the hypertrophic response induced by PE stimulation accompanying with increased LC3 II and p-AMPK expression. It was also found that CRA blunted cardiomyocyte hypertrophy and promoted autophagy in Angiotensin II (Ang II)-treated H9c2 cells. Moreover, to further verify whether CRA inhibits cardiac hypertrophy by the activation of autophagy, blockade of autophagy was achieved by CQ (an inhibitor of the fusion between autophagosomes and lysosomes) or 3-MA (an inhibitor of autophagosome formation). It was found that autophagy inhibition counteracts the protective effect of CRA on cardiac hypertrophy. Interestingly, AMPK knockdown with AMPKα2 siRNA counteracted LC3 II expression increase and the hypertrophic response inhibition caused by CRA in PE-treated H9c2 cells. CONCLUSION: These results suggest that CRA may protect against cardiac hypertrophy through regulating AMPK-dependent autophagy.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31729696

RESUMO

L-DOPA (L-dihydroxyphenylalanine) is a promising drug for Parkinson's disease and thereby has a growing annual demand. Tyrosine phenol-lyase (TPL)-based catalysis is considered to be a low-cost yet efficient route for biosynthesis of L-DOPA. TPL is a tetrameric enzyme that catalyzes the synthesis of L-DOPA from pyrocatechol, sodium pyruvate, and ammonium acetate. The implementation of TPL for L-DOPA production has been hampered and the need for the most efficient TPL source with higher L-DOPA production and substrate conversion rate is prevailing. This study involves identifying a novel TPL from Kluyvera intermedia (Ki-TPL) and displayed a robust expression in Escherichia coli. The recombinant strain YW000 carrying Ki-TPL proved strong catalytic activity with a highest L-DOPA yield compared with 16 other TPLs from different organisms. With a further aim to improve this efficiency, random mutagenesis of Ki-TPL was performed and a mutant namely YW021 was obtained. The whole cells of YW021 as biocatalyst yielded 150.4 g L-1 of L-DOPA with a 99.99 % of pyrocatechol conversion at the optimum condition of pH 8.0 at 25 °C, which is the highest level reported to date. Further, the homology modeling and structural analysis revealed the mutant residues responsible for the extensive L-DOPA biosynthesis.

7.
Phys Chem Chem Phys ; 21(45): 25047-25053, 2019 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-31690901

RESUMO

As an important pathway for energy storage and a key reaction in the carbon cycle, the CO2 electrochemical reduction reaction has recently gained significant interest. A variety of catalysts have been used to approach this topic experimentally and theoretically; however, the molecular level insight into the reaction mechanism is lacking due to the complexity of the surface processes and the challenges in probing the intermediate species. In this study, CO2 reduction reactions on polycrystalline Cu and Au electrodes were investigated in 0.1 M CO2-saturated NaHCO3 solution. In situ sum frequency generation (SFG) spectroscopy has been adopted to access the intermediates and products on the metal electrodes. On the Au electrode, only linearly adsorbed CO could be detected, and the reduction produced no hydrocarbon species. On the Cu electrode, C-H stretching vibrations corresponding to surface-adsorbed ethoxy species were observed, but no CO vibrations can be detected with SFG. The results revealed that the CO randomly adsorbed on the Cu surface, and the multiple orientations of the adsorbed species may be the reason for the formation of C-C bonding. These results demonstrate direct molecular level evidence for different reaction pathways on the Cu and Au electrodes.

8.
J Phys Condens Matter ; 32(9): 095402, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31689692

RESUMO

The changes of methane hydrate lattice with the decrease of cage occupancy were calculated by first-principles methods. The calculation results show that the decrease of the cages occupancy in sII and sH hydrate does not lead to large deformation in the lattice. Even if all the methane molecules are removed so that the hydrates have become new types of ice, the sII and sH lattices remain stable. The same conclusion is also true when the occupancy of the small cages in sI hydrate is reduced. However, the sI hydrate lattice will deform and almost collapse as the large cage occupancy decreases. These calculation results suggest that sI hydrate cannot exist with empty cages. Since the van der Waals-Platteeuw theory is based on the assumption that the stability of host lattice is independent of the occupancy of guest molecule, it would be applicable to sII and sH lattices, but not to sI hydrates. We propose a modification to the van der Waals-Platteeuw hypothesis so that the theory seems more reasonable.

9.
BMC Ophthalmol ; 19(1): 234, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31752875

RESUMO

BACKGROUND: To report a modified surgical technique for intrascleral intraocular lens (IOL) fixation with fewer anterior segment manipulations in eyes lacking sufficient capsular support. METHODS: Eyes from 14 patients who underwent 27-gauge needle-guided intrascleral IOL fixation with built-in 8-0 absorbable sutures were studied. The 8-0 absorbable sutures were inserted into 27-gauge round needles and used to create sclerotomies at the 4 o'clock and 10 o'clock positions under the scleral flap. The sutures were used to tie knots at the end of each haptic and guide haptic externalization through the sclerotomy. After externalization, a sufficient flange was created at the end of each haptic and fixed under the scleral flaps. The best corrected visual acuity (BCVA), corneal endothelial cell density (ECD), IOL tilt and decentration, previous surgery history, and complications were determined. RESULTS: Fourteen cases were analyzed. The majority of eyes exhibited an improvement in the BCVA after surgery. When comparing the last follow-up to preoperative visual acuity, the mean change in BCVA was + 26.32 letters (p = 0.011). Postoperative complications included postoperative hypotony in 3 eyes, ocular hypertension in 2 eyes. No cases of postoperative cystoid macular edema (CME), vitreous hemorrhage (VH), IOL dislocation, or endophthalmitis were observed. CONCLUSIONS: The 27-gauge needle-guided intrascleral IOL fixation technique with built-in 8-0 absorbable sutures is easy to perform with fewer anterior chamber manipulations and achieves both anatomical and optical stability.

10.
Horm Behav ; : 104640, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31765661

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disease that severely affects the health and lifespan of the elderly worldwide. Recently, the correlation between AD and type 2 diabetes mellitus (T2DM) has received intensive attention, and a promising new anti-AD strategy is the use of anti-diabetic drugs. Oxyntomodulin (Oxm) is a peptide hormone and growth factor that acts on neurons in the hypothalamus. OXM activates glucagon-like peptide 1 (GLP-1) and glucagon (Gcg) receptors, facilitates insulin signaling and has neuroprotective effects against Aß1-42-induced cytotoxicity in primary hippocampal neurons. Here, we tested the effects of the protease-resistant analogue (D-Ser2)Oxm on spatial memory and synaptic plasticity and the underlying molecular mechanisms in the APP/PS1 transgenic mouse model of AD. The results showed that (D-Ser2)Oxm not only alleviated the impairments of working memory and long-term spatial memory, but also reduced the number of Aß plaques in the hippocampus, and reversed the suppression of hippocampal synaptic long-term potentiation (LTP). Moreover, (D-Ser2)Oxm administration significantly increased p-PI3K/p-AKT1 expression and decreased p-GSK3ß levels in the hippocampus. These results are the first to show an in vivo neuroprotective role of (D-Ser2)Oxm in APP/PS1 mice, and this role involves the improvement of synaptic plasticity, clearance of Aß and normalization of PI3K/AKT/GSK3ß cell signaling in the hippocampus. This study suggests that (D-Ser2)Oxm holds promise for the prevention and treatment of AD.

11.
Biotechnol Lett ; 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31768672

RESUMO

A novel enzyme immobilization method employing metal-organic framework (MOF) encapsulation and macroporous resin adsorption was developed in this study. Candida antarctica lipase B (CALB) was firstly encapsulated onto metal-organic frame structures (Zeolitic imidazole framework-8, ZIF-8) and further bonded to macroporous resin by physical adsorption. Under optimized immobilization conditions, the activity of the prepared immobilized lipase (CALB-ZIF-8@D101) determined via the methyl esterification of oleic acid was 38.4 U/mg. Compared with free lipase, the immobilized lipase exhibited improved thermal and operational stability and organic solvent tolerance. These results demonstrate that the immobilization method of ZIF-8 encapsulation and macroporous resin adsorption enhanced enzyme properties at a superior level.

12.
Biomacromolecules ; 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31696706

RESUMO

Eumelanin is a ubiquitous natural pigment that has a broad absorption across ultraviolet (UV, 100-400 nm) and visible wavelengths (400-700 nm) and can protect against radiation. Synthetic eumelanin with properties similar to natural eumelanin has been made using dopamine or dihydroxyindole. Here, we use solid-state nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy to elucidate the chemical structure of synthetic eumelanins (made from dopamine and l-3,4-dihydroxyphenylalanine precursors) and investigate how their structures change after intensive UVA (315-400 nm) exposure. We first confirm that polydopamine has indole units. Upon UV exposure, the pyrrole ring in this indole unit remains intact, and a fraction of the six-membered benzyl ring is broken and the indole potentially converted to furo[3,4-b]pyrrole. This change in the chemical structure is accompanied by a release of carbon dioxide. In addition, the sepia (natural) eumelanin used for comparison is more stable than the synthetic eumelanin. Understanding the UVA degradation mechanism of eumelanin will help reveal the role of eumelanin in skin cancer and in the design of more efficient UV stabilizers.

13.
Biomed Pharmacother ; 121: 109552, 2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31715370

RESUMO

Rhodiola rosea L., a worldwide botanical adaptogen, has been confirmed to possess protective effects of inflammatory injury for many diseases, including cardiovascular diseases, neurodegenerative diseases, diabetes, sepsis, and cancer. This paper is to review the recent clinical and experimental researches about the anti-inflammatory effects and the related mechanisms of Rhodiola rosea L. extracts, preparations, and the active compounds. From the collected information reviewed, this paper will provide the theoretical basis for its clinical application, and provide the evidences or guidance for future studies and medicinal exploitations of Rhodiola rosea L.

14.
Artigo em Inglês | MEDLINE | ID: mdl-31763751

RESUMO

An efficient and readily scalable thioetherification between 1,1-diphenylethene (DPE) and sodium arylsulfinate is developed for synthesis of 1,1-diphenylvinylsulfide (DPVS) with the yield up to 99%. The photophysical properties of DPVS show that the introduction of arylsulfenyl groups onto the parent molecule DPE makes DPVS a novel type of aggregation-induced emission (AIE) luminogens (AIEgens) with large Stoke's shift (up to 188 nm). These DPVSs are of AIE characteristic due to the restriction of intramolecular motions (RIM), proved by crystalline structure analysis. Importantly, the AIE performance of DPVS can be applied to sense picric acid, a nitroaromatic explosive in aqueous system by "turn-off" response.

15.
J Virol Methods ; : 113774, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31726113

RESUMO

Porcine Reproductive and Respiratory Syndrome (PRRS), an acute infectious disease caused by the porcine reproductive and respiratory syndrome virus (PRRSV), is one of the most devastating diseases affecting the global swine industry. In order to establish a multiplex real-time PCR method for the simultaneous detection of the classical PRRSV (C-PRRSV) strain, the highly pathogenic PRRSV (HP-PRRSV) strain and NADC30-like PRRSV (NL-PRRSV) strain, we designed specific primers and TaqMan fluorescent probes based on the Nsp2 target gene sequence of these three different PRRSV strains, and designed American-type PRRSV (PRRSV-U) special primers and probes based on the relatively conserved target gene sequence of ORF7. The method established in this study can quickly and accurately detect and differentiate three types of strains of clinical tissue samples, respectively. This method plays a key role in the rapid diagnosis and determination of PRRSV.

16.
BMC Urol ; 19(1): 105, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31666055

RESUMO

BACKGROUND: Benign prostatic hyperplasia (BPH) rarely occurs in children or young males. In this case report, a 29-year-old male patient diagnosed with BPH coexisting with ketamine-associated uropathy was reported to investigate the possible relationship between BPH and ketamine-associated uropathy as well as therapeutic strategies. CASE PRESENTATION: A 29-year-old male patient with a 3-year history of ketamine inhalation, complaining of dysuria with frequency and urgency, was admitted. Hydronephrosis, hydroureters, uneven bladder wall thickening and a tumour located in the outlet of the bladder were detected with computed tomography (CT). The patient agreed to cystoscopy under general anaesthesia. A spherical tumour with a diameter of approximately 2 cm was found to originate from the median lobe of the prostate and follicular lesions were diffusely distributed on the right bladder wall. The tumour and follicular lesions in the bladder were resected successfully, and pathology demonstrated BPH and chronic inflammation of the mucous membranes separately. The patient quit ketamine completely during the one-year follow-up. Dysuria was relieved completely and no tumour or follicular neoplasm recurrence was found. CONTRIBUTION: Inflammation in the urothelium, as a direct or indirect consequence of ketamine, may contribute to the development of BPH. Both surgical interventions to remove obstruction and ketamine cessation are necessary approaches.

17.
J Alzheimers Dis ; 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31683484

RESUMO

Exaggerated Ca2+ signaling might be one of primary causes of neural dysfunction in Alzheimer's disease (AD). And the intracellular Ca2+ overload has been closely associated with amyloid-ß (Aß)-induced endoplasmic reticulum (ER) stress and memory impairments in AD. Here we showed for the first time the neuroprotective effects of Xestospongin C (XeC), a reversible IP3 receptor antagonist, on the cognitive behaviors and pathology of APP/PS1 AD mice. Male APP/PS1-AD mice (n = 20) were injected intracerebroventricularly with XeC (3µmol) via Alzet osmotic pumps for four weeks, followed by cognition tests, Aß plaque examination, and ER stress-related protein measurement. The results showed that XeC pretreatment significantly improved the cognitive behavior of APP/PS1-AD mice, raising the spontaneous alteration accuracy in Y maze, decreasing the escape latency and increasing the target quadrant swimming time in Morris water maze; XeC pretreatment also reduced the number of Aß plaques and the overexpression of ER stress proteins 78 kDa glucose-regulated protein (GRP-78), caspase-12, and CAAT/enhancer-binding protein (C/EBP) homologous protein (CHOP) in the hippocampus of APP/PS1 mice. In addition, in vitro experiments showed that XeC effectively ameliorated Aß1 - 42-induced early neuronal apoptosis and intracellular Ca2+ overload in the primary hippocampal neurons. Taken together, IP3R-mediated Ca2+ disorder plays a key role in the cognitive deficits and pathological damages in AD mice. By targeting the IP3 R, XeC might be considered as a novel therapeutic strategy in AD.

18.
Opt Express ; 27(20): 28293-28312, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31684584

RESUMO

Inter-reflection removal is vital for complex-scene reconstruction. However, most methods assume that the tested surface is a diffuse, and are limited to removal of inter-reflection caused only by diffuse reflections. For all kinds of inter-reflections caused by diffuse and specular reflections, a micro-frequency shifting (MFS) projection technique is presented. Because the modulation variation with frequency in inter-reflection regions is larger than that of other regions, we use the MFS technique to detect inter-reflections, where patterns with specifically designed frequency-shifts and base frequencies are projected. Inter-reflections are detected through large variations in modulation, and removed using a regional-projection technique. Experimental results validate the effectiveness for diffuse and specular inter-reflection removal.

19.
Biomolecules ; 9(11)2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31690058

RESUMO

In the current study, corn steep liquor (CSL) is evaluated as an ideal raw agro-material for efficient lipid and docosahexaenoic acid DHA production by Aurantiochytrium sp. Low CSL level in medium (nitrogen deficiency) stimulated the biosynthesis of lipids and DHA while inhibiting cellular growth. The transcriptomic profiles of the Aurantiochytrium sp. cells are analyzed and compared when cultured under high (H group), normal (N group), and low (L group) levels of CSL in the medium. The discriminated transcriptomic profiles from the three groups indicates that changes in CSL level in medium result in a global change in transcriptome of Aurantiochytrium sp. The overall de novo assembly of cDNA sequence data generated 61,163 unigenes, and 18,129 of them were annotated in at least one database. A total of 5105 differently expressed (DE) genes were found in the N group versus the H group, with 2218 downregulated and 2887 upregulated. A total of 3625 DE genes were found in the N group versus the L group, with 1904 downregulated and 1721 upregulated. The analysis and categorization of the DE genes indicates that the regulation mechanism of CSL involved in the perception and transduction of the limited nitrogen signal, the interactions between the transcription factors (TFs) and multiple downstream genes, and the variations in downstream genes and metabolites, in sequence, are illuminated for the first time in the current study.

20.
Nucleic Acids Res ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31691819

RESUMO

Genome-wide association studies (GWASs) have revolutionized the field of complex trait genetics over the past decade, yet for most of the significant genotype-phenotype associations the true causal variants remain unknown. Identifying and interpreting how causal genetic variants confer disease susceptibility is still a big challenge. Herein we introduce a new database, CAUSALdb, to integrate the most comprehensive GWAS summary statistics to date and identify credible sets of potential causal variants using uniformly processed fine-mapping. The database has six major features: it (i) curates 3052 high-quality, fine-mappable GWAS summary statistics across five human super-populations and 2629 unique traits; (ii) estimates causal probabilities of all genetic variants in GWAS significant loci using three state-of-the-art fine-mapping tools; (iii) maps the reported traits to a powerful ontology MeSH, making it simple for users to browse studies on the trait tree; (iv) incorporates highly interactive Manhattan and LocusZoom-like plots to allow visualization of credible sets in a single web page more efficiently; (v) enables online comparison of causal relations on variant-, gene- and trait-levels among studies with different sample sizes or populations and (vi) offers comprehensive variant annotations by integrating massive base-wise and allele-specific functional annotations. CAUSALdb is freely available at http://mulinlab.org/causaldb.

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