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1.
Physiol Biochem Zool ; 93(1): 49-61, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31742477

RESUMO

The freeze-tolerant wood frog, Rana sylvatica, is one of few vertebrate organisms that can tolerate freezing, with up to 70% of its total body water being converted into extracellular ice. Physiologically, wood frogs show no signs of muscle movement, breathing, heartbeat, or brain activity for several weeks or months at a time but emerge unharmed upon thawing. Given that wood frogs rely mainly on carbohydrate metabolism during freezing, the involvement of the carbohydrate-responsive element-binding protein (ChREBP) in response to freezing is of interest. In liver tissue, protein and transcript levels of ChREBP increased by 1.4±0.09-fold and 1.9±0.26-fold, respectively, and nuclear distribution and DNA-binding activity rose by 2.0±0.08-fold and 1.5±0.08-fold, respectively. This enhanced transcriptional activity of ChREBP was corroborated by increased transcript expression of select downstream genes of fatty acid synthase, pyruvate kinase, and stearoyl-CoA desaturase in liver tissue. While liver tissue displayed ChREBP activation, in muscle tissue, ChREBP protein levels, DNA-binding activity, and downstream gene targets were generally found to decrease or to remain unchanged during freezing. Overall, our results demonstrate that ChREBP regulates metabolism in a tissue-dependent manner during freezing, when its activity is required for liver tissue but not for skeletal muscle tissue in wood frogs.

2.
Water Res ; 168: 115181, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31630018

RESUMO

In this study, zwitterionic polymer brushes with controlled architecture were grafted on the surface of gravity-driven membrane (GDM) via surface-initiated reaction to impart antifouling property. A variety of membrane characterization techniques were conducted to demonstrate the successful functionalization of zwitterionic polymers on PVDF hollow fiber membrane. The membrane underwent 90 min of reaction time possessing strong hydrophilicity and high permeability was determined as the optimal modified membrane. Long-term GDM dynamic fouling experiments operated for 30 days using sewage wastewater as feed solution indicated zwitterionic polymer modified membrane exhibit excellent membrane fouling resistance thus enhanced stable flux. Confocal laser scanning microscopy (CLSM) imaging implied that zwitterionic polymer modification significantly inhibit the adsorption of extracellular polymeric substances (EPS) which dominates fouling propensity, resulting in the formation of a thin biofilm with high porosity under synthetic functions of foulants deposition and microbial activities. Interfacial free energy prediction affirmed the presence of zwitterionic functional layer on membrane surface could substantially decrease the interactions (e.g., electrostatic attractions and hydrophobic effects) between membrane and foulants, thereby reduced flux decline and high stable flux. Our study suggests surface hydrophilic functionalization shows promising potential for improving the performance of ultra-low pressure filtration.


Assuntos
Membranas Artificiais , Polímeros , Biofilmes , Filtração , Esgotos
3.
Biomed Pharmacother ; 121: 109310, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31710895

RESUMO

Currently, there is no effective method to prevent renal interstitial fibrosis after acute kidney injury (AKI). In this study, we established and screened a new renal interstitial fibrosis rat model after cisplatin-induced AKI. Our results indicated that rats injected with 4 mg/kg cisplatin once a week for two weeks after firstly administrated with 6.5 mg/kg loading dose of cisplatin could set up a more accurate model reflecting AKI progression to renal interstitial fibrosis. Then, we investigated the effects and possible mechanisms of human umbilical cord blood mononuclear cells (hUCBMNCs) on renal tubular interstitial fibrosis after cisplatin-induced AKI. In rats injected with hUCBMNCs for four times, level of matrix metalloproteinase 7(MMP-7)in serum and urine, urinary albumin/creatinine ratio, tubular pathological scores, the relative collagen area of the tubulointerstitial region, endoplasmic reticulum dilation and the mitochondrial ultrastructural damage were significantly improved. The level of reactive oxygen species, α-smooth muscle actin (α-SMA), [NOD]-like pyrin domain containing protein 3 and cleaved-Caspase 3 in renal tissue decreased significantly. However, in rats injected with hUCBMNCs for two times, no significant difference was discovered in MMP-7 levels and urinary albumin/creatinine ratio. Although expression of α-SMA and the percentage areas of collagen staining in tubulointerstitial tissues were ameliorated in rats injected with hUCBMNCs for two times, the effects were significantly weaker than those in rats injected with hUCBMNCs for four times. Taken together, our study constructed a highly efficient, duplicable novel rat model of renal fibrosis after cisplatin-induced AKI. Multiple injections of hUCBMNCs may prevent renal interstitial fibrosis after cisplatin-induced AKI.

4.
J Ethnopharmacol ; 246: 112246, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31539577

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Kan-Lu-Hsiao-Tu-Tan (KLHTT) is a popular traditional Chinese medicine for treating various inflammatory diseases. AIM OF THE STUDY: The aim of the present study was to investigate the anti-inflammatory effects of KLHTT on human neutrophils and its therapeutic potential in treating imiquimod (IMQ)-induced psoriasis-like skin inflammation. MATERIALS AND METHODS: Spectrophotometry, flow cytometry, and microscopy with immunohistochemical staining were used to evaluate superoxide anion generation, elastase release, CD11b expression, adhesion, and neutrophil extracellular trap (NET) formation in activated human neutrophils. Reactive oxygen species (ROS) and reactive nitrogen species in cell-free systems were measured using a multi-well fluorometer or a spectrophotometer. A psoriasis-like skin inflammation was induced in mice using the IMQ cream. RESULTS: KLHTT suppressed superoxide anion generation, ROS production, CD11b expression, and adhesion in activated human neutrophils. In contrast, KLHTT failed to alter elastase release in activated human neutrophils. Additionally, KLHTT had an ROS-scavenging effect in the AAPH assay, but it did not scavenge superoxide anions directly in the xanthine/xanthine oxidase assay. Protein kinase C (PKC)-induced NET formation most commonly occurs through ROS-dependent mechanisms. KLHTT significantly inhibited phorbol 12-myristate 13-acetate, a PKC activator, inducing NET formation. Furthermore, topical KLHTT treatment reduced the area affected by psoriasis area and severity index (PASI) score and ameliorated neutrophil infiltration in IMQ-induced psoriasis-like skin inflammation in mice. CONCLUSIONS: Our data show that KLHTT has anti-neutrophilic inflammatory effects in inhibiting ROS generation and cell adhesion. KLHTT also mitigated NET formation, mainly via an ROS-dependent pathway. In addition, KLHTT reduced neutrophil infiltration and improved the severity of IMQ-induced psoriasis-like skin inflammation in mice. Therefore, KLHTT may prove to be a safe and effective psoriasis therapy in the future.

5.
ACS Nano ; 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31790192

RESUMO

When a microlens array is aligned and overlaid on an array of patterns with similar periodicity, a highly magnified image of the patterns is observed. This effect, known as moiré magnification, is used to reveal micropatterns that are unresolvable by the naked eye. These patterns are typically limited by print resolution to single color patterns. Here, we demonstrate the potential to selectively reveal more than one set of color patterns. By rotating a microlens array relative to a print containing three overlapping arrays of structural color patterns in 10° steps, each pattern array can be distinctly revealed with minimal crosstalk. This rotation-selective effect of moiré magnification is not seen in conventional microscopy. An advantage is that the moiré images are observable by the naked eye under incoherent illumination. We leverage nanoscale three-dimensional printing by using the two-photon lithography process to produce structural color pattern arrays in a single lithographic step with precisely aligned color pixels. We believe that this work can have applications in precise rotational-alignment tools, covert security documents, and information multiplexing devices.

6.
Pharmacol Res ; : 104581, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31794869

RESUMO

Interruption of the Warburg effect - the observation that un-stimulated macrophages reprogram their core metabolism from oxidative phosphorylation toward aerobic glycolysis to become pro-inflammatory M1 macrophages upon stimulation - is an emerging strategy for the treatment of cancer and anti-inflammatory diseases such as rheumatoid arthritis. We studied this process with view to the discovery of novel therapeutics, and found that tylophorine-based compounds targeted a ribonucleoprotein complex containing caprin-1 and mRNAs of c-Myc and HIF-1α in LPS/IFN-γ stimulated Raw264.7 cells, diminished the protein levels of c-Myc and HIF-1α, and consequently downregulated their targeted genes that are associated with the Warburg effect, as well as the pro-inflammatory iNOS and COX2. The tylophorine-based compound DBQ 33b significantly meliorated the severity and incidence of type II collagen-monoclonal antibody-induced rheumatoid arthritis and diminished gene expressions of c-Myc, HIF-1α, iNOS, COX2, TNFα, and IL-17A in vivo. Moreover, pharmacological inhibition of either c-Myc or HIF-1α exhibited similar effects as the tylophorine-based compound DBQ 33b, even though inhibition of c-Myc reversed the induction of iNOS and COX2 in LPS/IFN-γ stimulated Raw264.7 cells to a lesser degree. Therefore, simultaneous inhibition of both c-Myc and HIF-1α is efficacious for anti-inflammation in vitro and in vivo and merits further study.

7.
Sci Total Environ ; : 135224, 2019 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-31796275

RESUMO

Microbial remediation is a promising technique to remediate heavy metals contaminated soils. In this study, the cadmium (Cd)- resistant Citrobacter sp. XT1-2-2, isolated from heavy metals contaminated paddy soils, was investigated to evaluate the effect of this strain on soil Cd speciation, cellular Cd distribution, tissue Cd accumulation and rice biomass. The percentage of Cd2+ removal by Citrobacter sp. XT1-2-2 was up to 82.3 ± 2.1% within 240 min in the solution. The average content of soil soluble plus exchangeable and carbonate-bound fractions of Cd decreased, whereas Fe/Mn oxide-bound, organic matter-bound and residual fractions increased with bacteria inoculation. For the paddy soil inoculated with the XT1-2-2 strain, Cd concentrations of roots, culms, leaves and grains were significantly reduced by 24.1%, 46.9%, 41.5% and 66.7%, respectively. In addition, inoculation bacteria significantly increased the biomass of the roots, above-ground tissues and the rice grains. All results indicated that the XT1-2-2 strain had the ability to immobilize soil Cd and decrease Cd accumulation in rice grains. Therefore, the XT1-2-2 strain has potential for application to remediate Cd-contaminated paddy soils. It is possible to exploit a new bacterial-assisted technique for the remediation in Cd-contaminated paddy soils.

8.
Sci Rep ; 9(1): 18321, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31797961

RESUMO

The novel methods for efficient plant regeneration via direct somatic embryogenesis (SE) and SE-mediated transformation system under high concentration of NAA in Ranunculus sceleratus were established. On MS media containing a high concentration of NAA (10.0 mg/L) in the dark, all inoculated explants (root, stem and leaf) formed somatic embryos at high frequencies, respectively, 66.03, 126.47 and 213.63 embryoids per explant, and 100% of the embryoids developed into plantlets on 1/2 MS rooting media. Morphological and histological analyses revealed that SE in R. sceleratus followed a classical pattern. All inoculated explants can be used as receptors for genetic transformation in R. sceleratus, through direct SE-mediated method after Agrobacterium infection. RcLEC1-B, as a marker gene, changed the number and morphology of flower organs and the development of cuticle in R. sceleratus, which indicated that the efficient transgenic system of R. sceleratus was established. To our knowledge, this is the first observation that both direct SE and transgenic transformation system, via induction of a single plant growth regulator, have been successfully constructed in R. sceleratus.

9.
BMJ ; 367: l6373, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31801749

RESUMO

OBJECTIVE: To determine associations between important pre-arrest and intra-arrest prognostic factors and survival after in-hospital cardiac arrest. DESIGN: Systematic review and meta-analysis. DATA SOURCES: Medline, PubMed, Embase, Scopus, Web of Science, and the Cochrane Database of Systematic Reviews from inception to 4 February 2019. Primary, unpublished data from the United Kingdom National Cardiac Arrest Audit database. STUDY SELECTION CRITERIA: English language studies that investigated pre-arrest and intra-arrest prognostic factors and survival after in-hospital cardiac arrest. DATA EXTRACTION: PROGRESS (prognosis research strategy group) recommendations and the CHARMS (critical appraisal and data extraction for systematic reviews of prediction modelling studies) checklist were followed. Risk of bias was assessed by using the QUIPS tool (quality in prognosis studies). The primary analysis pooled associations only if they were adjusted for relevant confounders. The GRADE approach (grading of recommendations assessment, development, and evaluation) was used to rate certainty in the evidence. RESULTS: The primary analysis included 23 cohort studies. Of the pre-arrest factors, male sex (odds ratio 0.84, 95% confidence interval 0.73 to 0.95, moderate certainty), age 60 or older (0.50, 0.40 to 0.62, low certainty), active malignancy (0.57, 0.45 to 0.71, high certainty), and history of chronic kidney disease (0.56, 0.40 to 0.78, high certainty) were associated with reduced odds of survival after in-hospital cardiac arrest. Of the intra-arrest factors, witnessed arrest (2.71, 2.17 to 3.38, high certainty), monitored arrest (2.23, 1.41 to 3.52, high certainty), arrest during daytime hours (1.41, 1.20 to 1.66, high certainty), and initial shockable rhythm (5.28, 3.78 to 7.39, high certainty) were associated with increased odds of survival. Intubation during arrest (0.54, 0.42 to 0.70, moderate certainty) and duration of resuscitation of at least 15 minutes (0.12, 0.07 to 0.19, high certainty) were associated with reduced odds of survival. CONCLUSION: Moderate to high certainty evidence was found for associations of pre-arrest and intra-arrest prognostic factors with survival after in-hospital cardiac arrest. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42018104795.

10.
Nucleic Acids Res ; 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31701128

RESUMO

An integrative multi-omics database is needed urgently, because focusing only on analysis of one-dimensional data falls far short of providing an understanding of cancer. Previously, we presented DriverDB, a cancer driver gene database that applies published bioinformatics algorithms to identify driver genes/mutations. The updated DriverDBv3 database (http://ngs.ym.edu.tw/driverdb) is designed to interpret cancer omics' sophisticated information with concise data visualization. To offer diverse insights into molecular dysregulation/dysfunction events, we incorporated computational tools to define CNV and methylation drivers. Further, four new features, CNV, Methylation, Survival, and miRNA, allow users to explore the relations from two perspectives in the 'Cancer' and 'Gene' sections. The 'Survival' panel offers not only significant survival genes, but gene pairs synergistic effects determine. A fresh function, 'Survival Analysis' in 'Customized-analysis,' allows users to investigate the co-occurring events in user-defined gene(s) by mutation status or by expression in a specific patient group. Moreover, we redesigned the web interface and provided interactive figures to interpret cancer omics' sophisticated information, and also constructed a Summary panel in the 'Cancer' and 'Gene' sections to visualize the features on multi-omics levels concisely. DriverDBv3 seeks to improve the study of integrative cancer omics data by identifying driver genes and contributes to cancer biology.

11.
Eur J Pharmacol ; : 172781, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31706856

RESUMO

Inhibiting glutamate release can reduce neuronal excitability and is recognized as a key mechanism of anti-epileptic drugs. In this study, by using isolated nerve terminal (synaptosome) and slice preparations, we investigated the effect of asiatic acid, a triterpene isolated from Centella asiatica with antiepileptic activity, on glutamate release in the hippocampus of rats. In hippocampal synaptosomes, application of asiatic acid resulted in a concentration-dependent inhibition of 4-aminopyridine-evoked glutamate release. This inhibitory action was dependent on extracellular calcium, blocked by inhibiting the vesicular transporter, but was unaffected by inhibiting the glutamate transporter. In addition, asiatic acid decreased the 4-aminopyridine-induced increase in the intraterminal calcium and failed to alter the synaptosomal potential. Furthermore, the asiatic acid-mediated release inhibition was significantly suppressed by the N- and P/Q-type calcium channel inhibitor ω-conotoxin MVIIC or protein kinase C inhibitor GF109203X. Western blotting data in synaptosomes also revealed that asiatic acid reduced 4-aminopyridine-induced phosphorylation of protein kinase C. In hippocampal slices, asiatic acid decreased the frequencies of spontaneous excitatory postsynaptic currents without changing their amplitudes and glutamate-activated currents in CA3 pyramidal neurons. We also observed that asiatic acid significantly suppressed 4-aminopyridine-induced burst firing. These data suggest that, in rat hippocampal nerve terminals, asiatic acid attenuates the calcium influx via N- and P/Q-type calcium channels, subsequently suppressing protein kinase C activity and decreasing glutamate release.

12.
Adv Mater ; : e1906352, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31746042

RESUMO

Janus monolayers, a class of two-faced 2D materials, have received significant attention in electronics, due to their unusual conduction properties stemming from their inherent out-of-plane asymmetry. Their photonic counterparts recently allowed for the control of hydrogenation/dehydrogenation processes, yielding drastically different responses for opposite light excitation spins. A passive Janus metasurface composed of cascaded subwavelength anisotropic impedance sheets is demonstrated. By introducing a rotational twist in their geometry, asymmetric transmission with the desired phase function is realized. Their broken out-of-plane symmetry realizes different functions for opposite propagation directions, enabling direction-dependent versatile functionalities. A series of passive Janus metasurfaces that enable functionalities including one-way anomalous refraction, one-way focusing, asymmetric focusing, and direction-controlled holograms are experimentally demonstrated.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31746123

RESUMO

Regenerative stem cell-based therapies for bronchopulmonary dysplasia (BPD), the most common preterm birth complication, demonstrate promise in animals. Failure to objectively appraise available preclinical data and identify knowledge gaps could jeopardize clinical translation. We performed a systematic review and network meta-analysis (NMA) of preclinical studies testing cell-based therapies in experimental neonatal lung injury. Fifty-three studies assessing 15 different cell-based therapies were identified: 35 studied the effects of mesenchymal stromal cells (MSCs) almost exclusively in hyperoxic rodent models of BPD. Exploratory NMAs, for select outcomes, suggest that MSCs are the most effective therapy. Although a broad range of promising cell-based therapies has been assessed, few head-to-head comparisons and unclear risk of bias exists. Successful clinical translation of cell-based therapies demands robust preclinical experimental design with appropriately blinded, randomized, and statistically powered studies, based on biological plausibility for a given cell product, in standardized models and endpoints with transparent reporting. Stem Cells Translational Medicine 2019.

14.
J Neurosurg Sci ; 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31738028

RESUMO

BACKGROUNDS: Glyoxalase I (GLO1), a ubiquitous enzyme involved in the process of detoxification of methylglyoxal in the cellular glycolysis pathway, was reported to be highly expressed in human tumor. It has also been found that GLO1 is associated with tumor cell survival and proliferation in some types of cancer, such as pancreatic cancer, hepatocellular carcinoma and gastric cancer. However, the role of GLO1 in glioma has not been clarified. The purpose of present study is to explore the expression pattern of GLO1 and whether the expression level of GLO1 is associated with the unfavorable clinical outcomes of patients with glioma. METHODS: Quantitative RT-PCR and immunohistochemistry staining were used to investigate the mRNA and protein level of GLO1 in glioma tissues together with normal brain tissues. The prognostic role of GLO1 in glioma patients was assessed using univariate and multivariate analyses. Clinical outcomes were estimated by using the Kaplan-Meier analysis and the log-rank test. The function of GLO1 in glioma cell lines were investigated by in vitro experiments. RESULTS: Expression level of GLO1 was higher in glioma tissues than that in normal brain tissues. High GLO1 expression was significantly correlated with WHO grade and the poor overall survival time in glioma patients. Moreover, GLO1 was also defined as an unfavorable prognosis factor. Overexpression of GLO1 in the glioma cell line U87 can enhance the tumor cell proliferation, migration and invasion. Whereas, knockdown of GLO1 can suppress those abilities. CONCLUSIONS: Our studies demonstrated that GLO1 was highly expressed in glioma tissues and significantly correlated with the poor prognosis of glioma patients. It indicated that GLO1 might serve as a new prognostic predictor and therapeutic target for glioma treatment.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31741254

RESUMO

PURPOSE: To present the first case proposing the use of preimplantation genetic testing for monogeneic disorders for Kallmann syndrome, providing comprehensive care in the genomic era of precision medicine. METHODS: Gonadotropin therapy was used for spermatogenesis, followed by in vitro fertilization by intracytoplasmic sperm injection and embryo transfer. Cross-generational targeted next-generation sequencing was then done for genes known to cause Kallmann syndrome. RESULTS: A heterozygous mutation at codon 102 of the FGFR1 gene was found in the patient, but the father was found to have the same mutation yet is unaffected by Kallmann syndrome. Since no causative mutation was found, a de novo or sporadic mutation was suspected as the cause of Kallmann syndrome in this case. CONCLUSIONS: Comprehensive care must be available for male Kallmann syndrome patients, as treatment should not stop at spermatogenesis, but continue with genetic counseling due to possible inheritance.

16.
J Cataract Refract Surg ; 45(11): 1665-1669, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31706519

RESUMO

PURPOSE: To evaluate semiautomated surgical lens extraction procedures using the optical coherence tomography (OCT)-integrated Intraocular Robotic Interventional Surgical System. SETTING: Stein Eye Institute and Department of Mechanical and Aerospace Engineering, University of California, Los Angeles, USA. DESIGN: Experimental study. METHODS: Semiautomated lens extraction was performed on postmortem pig eyes using a robotic platform integrated with an OCT imaging system. Lens extraction was performed using a series of automated steps including robot-to-eye alignment, irrigation/aspiration (I/A) handpiece insertion, anatomic modeling, surgical path planning, and I/A handpiece navigation. Intraoperative surgical supervision and human intervention were enabled by real-time OCT image feedback to the surgeon via a graphical user interface. Manual preparation of the pig-eye models, including the corneal incision and capsulorhexis, was performed by a trained cataract surgeon before the semiautomated lens extraction procedures. A scoring system was used to assess surgical complications in a postoperative evaluation. RESULTS: Complete lens extraction was achieved in 25 of 30 eyes. In the remaining 5 eyes, small lens pieces (≤1.0 mm3) were detected near the lens equator, where transpupillary OCT could not image. No posterior capsule rupture or corneal leakage occurred. The mean surgical duration was 277 seconds ± 42 (SD). Based on a 3-point scale (0 = no damage), damage to the iris was 0.33 ± 0.20, damage to the cornea was 1.47 ± 0.20 (due to tissue dehydration), and stress at the incision was 0.97 ± 0.11. CONCLUSIONS: No posterior capsule rupture was reported. Complete lens removal was achieved in 25 trials without significant surgical complications. Refinements to the procedures are required before fully automated lens extraction can be realized.

18.
Sci Rep ; 9(1): 17781, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31780756

RESUMO

Regardless of the dissimilarity in the crystal symmetry, the two-dimensional GaSe materials grown on GaAs(001) substrates by molecular beam epitaxy reveal a screw-dislocation-driven growth mechanism. The spiral-pyramidal structure of GaSe multi-layers was typically observed with the majority in ε-phase. Comprehensive investigations on temperature-dependent photoluminescence, Raman scattering, and X-ray diffraction indicated that the structure has been suffered an amount of strain, resulted from the screw-dislocation-driven growth mechanism as well as the stacking disorders between monolayer at the boundaries of the GaSe nanoflakes. In addition, Raman spectra under various wavelength laser excitations explored that the common ε-phase of 2D GaSe grown directly on GaAs can be transformed into the ß-phase by introducing a Se-pretreatment period at the initial growth process. This work provides an understanding of molecular beam epitaxy growth of 2D materials on three-dimensional substrates and paves the way to realize future electronic and optoelectronic heterogeneous integrated technology as well as second harmonic generation applications.

19.
Neurotoxicol Teratol ; 77: 106848, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31756371

RESUMO

Acrylamide is a food-borne chemical with well-known neurotoxic properties. To date, the toxicity mechanisms of chronic acrylamide exposure are not fully understood. Using the genetic model Caenorhabditis elegans, we found that chronic acrylamide exposure induces a locomotor defect that is characterized by severe uncoordination of muscle movement that is distinct from an overall reduction in activity. C. elegans exhibiting chronic acrylamide-induced locomotor defects show significant degeneration to the dopaminergic and cholinergic, but not GABAergic motor neurons. Degeneration of the dopaminergic and cholinergic neurons are found in 58% to 67% of C. elegans after chronic acrylamide exposure, with the varying degrees of severity ranging from neuronal blebbing to complete dendrite loss. The observed pattern of neurotoxicity does not have a heritable effect, as parental exposure to chronic acrylamide does not lead to neurodegeneration in the developed offspring. Overall, these finding illustrate that chronic acrylamide exposure cause locomotor defects by inducing degeneration of specific neuron types in C. elegans.

20.
J Cell Mol Med ; 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31774937

RESUMO

TIM-4 plays an important role in ischaemia-reperfusion injury of liver and kidney; however, the effects of TIM-4 on cerebral ischaemia-reperfusion injury (IRI) are unknown. The purpose of the present study was to investigate the potential role of TIM-4 in experimental brain ischaemia-reperfusion injury. In this study, cerebral ischaemia reperfusion was induced by transient middle cerebral artery occlusion (MCAO) for 1 hour in C57/BL6 mice. The TIM-4 expression was detected in vivo or vitro by real-time quantitative polymerase chain reaction, Western blot and flow cytometric analysis. In vivo, the administration of anti-TIM-4 antibodies significantly suppressed apoptosis, inhibited inflammatory cells and enhanced anti-inflammatory responses. In vitro, activated microglia exhibited reduced cellular proliferation and induced IRI injury when co-cultured with neurons; these effects were inhibited by anti-TIM-4 antibody treatment. Similarly, microglia transfected with TIM-4 siRNA and stimulated by LPS + IFN-γ alleviated the TIM-4-mediated damage to neurons. Collectively, our data indicate that the inhibition of TIM-4 can improve the inflammatory response and exerts a protective effect in cerebral ischaemia-reperfusion injury.

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