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1.
Acta Neurochir Suppl ; 127: 43-46, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31407061

RESUMO

Early brain injury is now considered as an important cause of delayed neurological deterioration after aneurysmal subarachnoid hemorrhage (SAH), and neuronal apoptosis is one of the constituents of early brain injury. Caspase family is popular proteases in apoptotic pathways, but there also exist caspase-independent cell death pathways in many pathologic states. In this study, we investigated the ratio of caspase-related and caspase-unrelated neuronal deaths in a mice endovascular perforation SAH model. At 24 h after SAH, about half of neurons in the perforation-side cortex showed increased cleaved caspase-3 immunoreactivity. On the other hand, about half of cleaved caspase-3-immunonegative neurons showed abnormal morphology, suggesting that they were in the process of some sort of cell death in the absence of caspase-3 activity. These findings suggest that both caspase-dependent and caspase-independent signaling pathways may cause neuronal death after SAH.

2.
Acta Neurochir Suppl ; 127: 55-58, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31407063

RESUMO

Vasospasm after subarachnoid hemorrhage (SAH) has been studied, but the mechanisms remain to be unveiled. Tenascin-C (TNC), which is a matricellular protein and reported to increase in spastic cerebral artery wall after SAH, is a ligand for both Toll-like receptor 4 (TLR4) and epidermal growth factor receptor (EGFR). Our previous studies suggested the involvement of TNC and these receptors in vasoconstriction or vasospasm after SAH. In this study, we investigated whether upregulation of TNC and TLR4 is observed and if an EGFR inhibitor has suppressive effects against them in a mice endovascular perforation SAH model. At 24 h after SAH, TNC and TLR4 expressions were widely observed in spastic cerebral arteries, and these expressions were suppressed by the administration of an EGFR inhibitor. From these results, EGFR inhibitors possibly suppress the expression of not only EGFR but also TLR4 at least partly through regulating TNC upregulation. More studies are needed to clarify the precise mechanisms linking these receptors.

3.
Acta Neurochir Suppl ; 127: 65-68, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31407065

RESUMO

Despite advances in diagnosis and treatment of subarachnoid hemorrhage (SAH), combined morbidity and mortality rate in SAH patients accounted for greater than 50%. Many prognostic factors have been reported including delayed cerebral ischemia, cerebral vasospasm-induced infarction, and shunt-dependent hydrocephalus as potentially preventable or treatable causes. Recent experimental studies emphasize that early brain injury, a concept to explain acute pathophysiological events that occur in brain before onset of cerebral vasospasm within the first 72 h of SAH, may be more important than cerebral vasospasm, a classically important determinant of poor outcome, in post-SAH outcome. Galectin-3 is known for one of matricellular proteins and a mediator of inflammation in the central nervous system. Galectin-3 was also reported to contribute to poor outcomes in SAH patients, but the role of galectin-3 after SAH has not been determined. We produced experimental SAH mice, of which the top of the internal carotid artery was perforated by 4-0 monofilament, and evaluated effects of a galectin-3 inhibitor. We assessed neurological scores and brain water content at 24 h. The administration of a galectin-3 inhibitor significantly ameliorated brain edema and neuronal score in experimental SAH mice.

4.
Acta Neurochir Suppl ; 127: 91-96, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31407069

RESUMO

Toll-like receptor 4 (TLR4) is expressed in various cell types in the central nervous system and exerts maximal inflammatory responses among the TLR family members. TLR4 can be activated by many endogenous ligands having damage-associated molecular patterns including heme and fibrinogen at the rupture of a cerebral aneurysm, and therefore its activation is reasonable as an initial step of cascades to brain injuries after aneurysmal subarachnoid hemorrhage (SAH). TLR4 activation induces tenascin-C (TNC), a representative of matricellular proteins that are a class of inducible, nonstructural, secreted, and multifunctional extracellular matrix glycoproteins. TNC is also an endogenous activator and inducer of TLR4, forming positive feedback mechanisms leading to more activation of the signaling transduction. Our studies have demonstrated that TLR4 as well as TNC are involved in inflammatory reactions, blood-brain barrier disruption, neuronal apoptosis, and cerebral vasospasm after experimental SAH. This article reviews recent understanding of TLR4 and TNC in SAH to suggest that the TLR4-TNC signaling may be an important therapeutic target for post-SAH brain injuries.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31486173

RESUMO

Herein, we report a new D-A-D' type pure organic molecule, named as ODFRCZ with unique triple-emission character covering fluorescence, phosphorescence and delayed fluorescence (DF). It is found that the phosphorescence of ODFRCZ has a rather long lifetime of ~350 ms at room temperature. One dimer of ODFRCZ with enhanced parallel molecular packing acts more effectively to prompt ISC processes which further generates RTP, due to the larger transition dipole moment and closer energy level between S1 and Tn. To the best of our knowledge, ODFRCZ is a rarely reported organic RTP molecule that shows dual-stimuli responsiveness of dual-mode mechanochromism (fluorescence redshift and RTP/DF on-off switch) and reversible crystal-state photochromism. This work may broaden our knowledge for stimuli-responsive RTP organic molecules and lay the foundation for their wide applications.

6.
J Cell Biochem ; 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31478224

RESUMO

Studies investigating the relationships between the polymorphisms in the X-ray repair cross complementing 1 (XRCC1) gene and the susceptibility of hepatocellular carcinoma (HCC) remained controversial, therefore, we assessed this associations by metaanalysis and trial sequential analysis (TSA). PubMed, Embase, Google Scholar, Chinese National Knowledge Infrastructure and Baidu Scholar were comprehensively screened to retrieve relevant studies up to May 20, 2019. A total of 32 studies was included. Significant associations were discovered in the overall and subgroup analysis in these three polymorphisms. Interestingly, the decreased risk of HCC was detected in the Indians for the rs24587 polymorphism. TSA indicated the required information size for the rs25487 polymorphism were reached, but for the rs25489 and rs1799782 polymorphisms, more well-designed trials were required. Sensitivity analysis implied our results were stable; no publication bias was observed in the rs25487 and rs1799782 polymorphisms. The bioinformatic analysis indicate that the rs1799782 polymorphism is probably damaging and has an influence on the XRCC1 protein function. Our study indicated that the XRCC1 rs25487 was a risk factor for the susceptibility of HCC, which was verified by the TSA. In addition, the rs25489 and rs1799782 polymorphisms were associated with increased risk of HCC. In the subgroup analysis, increased risks were detected in some subgroups (in accordance with Hardy-Weinberg equilibrium, Chinese groups, Mongoloid subgroup, polymerase chain reaction-restriction fragment length polymorphisms and more than 300 subgroups), moreover, decreased HCC risk of the rs25487 polymorphism was firstly observed, which required further studies to verify.

7.
IEEE Trans Cybern ; 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31478886

RESUMO

This article presents an adaptive output feedback approach of nonlinear multi-input-multi-output (MIMO) systems with time-varying state constraints and unmeasured states. An adaptive approximator is designed to approximate the unknown nonlinear functions existing in the state-constrained systems with immeasurable states. To deal with the tracking problem of such systems, a state observer with time-varying barrier Lyapunov functions (BLFs) is introduced in the controller design procedure. The backstepping design with time-varying BLFs is utilized to guarantee that all system states remain within the time-varying-constrained interval. The constant constraint is only the special case of the time-varying constraint which is more general in the real systems. The proposed control approach guarantees that all signals in the closed-loop systems are bounded and the tracking errors converge to a bounded compact set, and time-varying full-state constraints are never violated. A simulation example is given to confirm the feasibility of the presented control approach in this article.

8.
Int J Mol Sci ; 20(17)2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31480391

RESUMO

Salinity is one of the most decisive environmental factors threatening the productivity of crop plants. Understanding the mechanisms of plant salt tolerance is critical to be able to maintain or improve crop yield under these adverse environmental conditions. Plant membranes act as biological barriers, protecting the contents of cells and organelles from biotic and abiotic stress, including salt stress. Alterations in membrane lipids in response to salinity have been observed in a number of plant species including both halophytes and glycophytes. Changes in membrane lipids can directly affect the properties of membrane proteins and activity of signaling molecules, adjusting the fluidity and permeability of membranes, and activating signal transduction pathways. In this review, we compile evidence on the salt stress responses of the major membrane lipids from different plant tissues, varieties, and species. The role of membrane lipids as signaling molecules in response to salinity is also discussed. Advances in mass spectrometry (MS)-based techniques have largely expanded our knowledge of salt-induced changes in lipids, however only a handful studies have investigated the underlying mechanisms of membrane lipidome regulation. This review provides a comprehensive overview of the recent works that have been carried out on lipid remodeling of plant membranes under salt treatment. Challenges and future perspectives in understanding the mechanisms of salt-induced changes to lipid metabolisms are proposed.

9.
FASEB J ; : fj201900483RR, 2019 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-31480859

RESUMO

Chemotherapy resistance is one of the most common causes of death among patients with ovarian cancer, and identifying novel antitumor agents is a priority. Here, we report that the novel molecule 2-(anaphthoyl)ethyltrimethylammonium iodide (α-NETA) induces epithelial ovarian cancer (EOC) cell pyroptosis through the gesdermin-d (GSDMD)/caspase-4 pathway. Furthermore, Cell Counting Kit-8 fluorescence-activated cell sorting analysis showed that α-NETA treatment led to cell death in different ovarian cancer cell lines, including Ho8910, Ho8910PM, and A2780. Morphologic examination by electron microscopy indicated that cells treated with α-NETA produced multiple microbubbles, typical of cells undergoing pyroptosis. α-NETA also significantly increased expression of pyroptosis-associated molecules including caspase-4 and GSDMD in EOC cells. Knockdown of either caspase-4 or GSDMD in ovarian cancer cells strongly interfered with α-NETA cell-killing activity, indicating that α-NETA acts through the pyroptosis pathway. In vivo, α-NETA treatment dramatically decreased the size of EOC tumors in mice. Our findings suggest that α-NETA represents a potential new antitumor molecule or lead compound for EOC chemotherapy.-Qiao, L., Wu, X., Zhang, J., Liu, L., Sui, X., Zhang, R., Liu, W., Shen, F., Sun, Y., Xi, X. α-NETA induces pyroptosis of epithelial ovarian cancer cells through the GSDMD/caspase-4 pathway.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31482718

RESUMO

We reported a novel HIV-1 circulating recombinant form among three epidemiologically unlinked patients through men having sex with men (MSM) in Hebei Province, China. It was named CRF103_01B (this is temporary as we have not received the CRF number from HIV databases). A near full-length genome (NFLG) phylogenetic tree showed that CRF103_01B was generated by three B (Western origin) segments and CRF01_AE that was described as cluster 5 lineage of CRF01_AE (CRF01-5). The emergence of CRF103_01B increased the complexity of the HIV-1 epidemic in China.

11.
Mol Neurobiol ; 2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31494826

RESUMO

Recently, dimethyl fumarate (DMF) and Korean red ginseng (ginseng), based on their purported antioxidative and anti-inflammatory properties, have exhibited protective potential in various neurological conditions. Their effects on cerebral ischemia and underlying mechanisms remain inconclusive; however, increasing evidence indicates the involvement of the transcriptional factor Nrf2. This study evaluated the preventive effects of DMF and ginseng on hippocampal neuronal damage following hypoxia-ischemia (HI) and assessed the contributions of reactive gliosis and the Nrf2 pathway. Adult wild type (WT) and Nrf2-/- mice were pretreated with DMF or ginseng for 7 days prior to HI. At 24 h after HI, DMF or ginseng significantly reduced infarct volume (52.5 ± 12.3% and 47.8 ± 10.7%), brain edema (61.5 ± 17.4% and 39.3 ± 12.8%), and hippocampal CA1 neuronal degeneration, and induced expressions of Nrf2 target proteins in WT, but not Nrf2-/-, mice. Such hippocampal neuroprotective benefits were also observed at 6 h and 7 days after HI. The dynamic attenuation of reactive gliosis in microglia and astrocytes correlated well with this sustained neuroprotection in an Nrf2-dependent manner. In both early and late stages of HI, astrocytic dysfunctions in extracellular glutamate clearance and water transport, as indicated by glutamine synthetase and aquaporin 4, were also attenuated after HI in WT, but not Nrf2-/-, mice treated with DMF or ginseng. Together, DMF and ginseng confer robust and prolonged Nrf2-dependent neuroprotection against ischemic hippocampal damage. The salutary Nrf2-dependent attenuation of reactive gliosis may contribute to this neuroprotection, offering new insight into the cellular basis of an Nrf2-targeting strategy for stroke prevention or treatment.

12.
Semin Radiat Oncol ; 29(4): 348-353, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31472737

RESUMO

Administrative claims data are big data generated from healthcare encounters. Claims data contain information on insurance payment as well as clinical diagnoses and procedure codes to ascertain medical conditions and treatments, making them valuable sources for economic evaluation research. This paper offers an introductory overview of the use of claims data for oncology-related cost-of-illness, cost comparison, and cost-effectiveness analyses. We reviewed analytical methods commonly employed in these analyses, such as the phase of care approach and net costing method for cost-of-illness studies, propensity score matching methods for cost comparison studies, and net benefit regression models for cost-effectiveness studies. We used published studies to explain each method and to discuss methodological challenges of conducting economic studies using claims data.

14.
Artigo em Inglês | MEDLINE | ID: mdl-31507170

RESUMO

The synthesis of large-area and high-quality 2D MoS2 is undoubtedly a significant challenge till now. In this work, an effective strategy for achieving 2D MoS2 with enlarged grain size by Ni-foam-based trickle-flow ALD was suggested, by which MoS2 grain sizes up to 420 nm (monolayer sample) and 400 nm (five-layer sample) were obtained under the covering of 1 mm thick of Ni foam with 2 mm gap from the substrate at 460 °C. In terms of specific ALD experiments, Ni foam with certain thickness placed on top of substrate made the original precursor flow into a trickle-fluidization source flow, which decreased the nucleation density effectively. Thus, MoS2 with enlarged grain size were obtained based on the typical ALD mechanism of large-scale vertical growth under the action of steric hindrance after planar parallel growth around crystal nucleus. In addition, Ni foam also founded a stable temperature field by enhancing the heat transfer around the substrate and thus improved its crystallinity.

15.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(9): 914-917, 2019 Sep 10.
Artigo em Chinês | MEDLINE | ID: mdl-31515789

RESUMO

OBJECTIVE: To explore the genetic basis of a child with chronic kidney disease featuring renal shrinkage and creatinine increase. METHODS: Peripheral venous blood samples were taken from the child, his brother and two parents and subjected to whole exome sequencing. Suspected mutations were verified by Sanger sequencing. Bioinformatic analysis was carried out to predict the influence of mutations on the structure and function of the protein product. RESULTS: High-throughput and Sanger sequencing revealed that the child has carried compound heterozygous mutations of the COL4A4 gene, namely c.4550T>G in exon 47 (inherited from his mother) and c.199C>T in exon 5 (inherited from his father). Neither mutation was reported previously. Bioinformatic analysis showed that both mutations have located in highly conserved regions. The same mutations were not found in his brother. CONCLUSION: The compound heterozygous c.4550T>G and c.199C>T mutations probably underlie the disease in this child. The findings have enriched the mutation spectrum of the COL4A4 gene.

16.
Spectrochim Acta A Mol Biomol Spectrosc ; 225: 117508, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31499393

RESUMO

By taking advantage of the intramolecular charge transfer (ICT) process, we presented a novel fluorescent probe IPY-SO2 based on imidazo[1,5-α]pyridine derivative for detecting SO32- with a low detection limit (70 nM). Combining its favorable turn-on fluorescence feature (75-fold), rapid response (5 min), high selectivity, large Stokes shift (174 nm) and low cytotoxicity, IPY-SO2 was successfully applied to imaging SO32 in living MCF-7 cells and zebrafish.

17.
Biosens Bioelectron ; 144: 111660, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31505404

RESUMO

MicroRNA-155 (miRNA-155) is a typical cancer-related biomarker, which often exists at ultralow concentrations in the plasma or body fluids of early patients. In this work, a novel label-free platform for ultrasensitive miRNA-155 detection was designed based on the precise fabrication of molybdenum disulfide (MoS2) by atomic layer deposition (ALD). Au nanoparticles (AuNPs)@MoS2 nanostructures were the core parts for the detection electrode, and the measurement precision of the sensing platform was modulated and optimized by ALD-based thickness and shape control of ultrathin MoS2 nanoflakes (thickness: ~14 nm, about 20 layers, uniform continuous distribution). In the detection experiment, MoS2 nanoflakes served as a conductive skeleton to support more AuNPs, and the results showed that the effective control of their morphology and thickness was of vital importance for ultrasensitive acquisition of detection signals. With using toluidine blue (TB) as a hybridization indicator, ultrasensitive detection record ranging from 1 fM to 10 nM with a detection limit of 0.32 fM can be achieved.

18.
Pharmacology ; : 1-10, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31514184

RESUMO

BACKGROUND AND PURPOSE: Intracellular calcium concentration ([Ca2+]i) overload occurs in myocardial ischemia and -reperfusion. The augmentation of the late sodium current (INaL) causes intracellular Na+ accumulation and subsequent [Ca2+]i overload via the reverse mode of the Na+/Ca2+ exchange current (reverse-INCX), which can lead to arrhythmia and cardiac dysfunction. Thus, inhibition of INaL is a potential therapeutic approach for ischemic heart disease. The aim of this study was to investigate the effects of thyroid hormone on augmented INaL, reverse-INCX, altered action potential duration (APD), and [Ca2+]i concentration in hypoxia/reoxygenation (H/R)-induced ventricular myocytes in vitro. METHODS: The transient Na+ current (INaT), INaL, reverse-INCX, and APs were recorded using a whole-cell patch-clamp technique in neonatal mouse ventricular myocytes. [Ca2+]i concentration alteration were, respectively, observed by confocal microscopy and flow cytometry. RESULTS: Triiodothyronine (T3) pretreatment decreased the INaL in a concentration-dependent manner. H/R injury aggravated the INaL, INaT, and reverse-INCX in cardiomyocytes and increased the continuous accumulation of [Ca2+]i (p < 0.05). The application of T3 prior to H/R injury significantly decreased the increased INaL, INaT, and reverse-INCX and blunted the [Ca2+]i increase. Furthermore, T3 pretreatment shortened the APD induced by H/R injury. CONCLUSION: T3 inhibited H/R-increased INaL and reverse INCX augmentation, shortened the APD, and diminished [Ca2+]i overload, indicating a potential therapeutic use of T3 as an INaL inhibitor to maintain Ca2+ homeostasis and protect cardiomyocytes against H/R injury.

19.
Neurobiol Aging ; 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31500908

RESUMO

In the present study, a novel mutation in the presenilin 1 gene was discovered in an Iraq-native patient with early-onset Alzheimer's disease, who presented with speech impairment and memory decline at age 46 years. Magnetic resonance imaging showed a frontotemporal atrophy. Sanger sequencing identified a heterozygous T to A transversion at position 815 (c.815T>A) in the presenilin 1 gene (PSEN1), resulting in a novel missense mutation at codon 272 from valine to aspartate (V272D). We tested this PSEN1 mutation in vitro and found V272D resulted in an altered Aß42/40 ratio.

20.
J Orthop Surg Res ; 14(1): 287, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477182

RESUMO

BACKGROUND: The thumb accounts for 50% of the total hand function. This study reports the functional outcomes and complications of people with traumatic thumb amputations who underwent toe-to-thumb reconstruction. METHODS: From January 2013 to January 2018, 29 patients with second-degree thumb defect underwent thumb reconstruction with distal phalangeal braided toenail flap. The footscan foot pressure gait analysis system was used to measure the index changes of the same foot before and after 1, 3 and 6 months. The contact area, peak pressure, impulse value, contact time of each gait phase, centre of gravity coordinate and foot balance were analysed statistically. RESULTS: Twenty-nine cases of thumb reconstruction recovered well. After following up for 6-15 months, the appearance of the reconstructed thumb was close to normal, and the sensation was restored to S3+. The two-point discrimination was 6-8 mm, and the function of the thumb was good. The function of the donor foot was well restored, and no skin ulceration, pain and claudication were noted during walking. Compared with that before the operation, the biomechanical indices of the donor foot were basically restored to normal 6 months after the operation. Only the stress and impulse values of the third metatarsal head were significantly increased, forming a stress concentration area centred on the third metatarsal head. CONCLUSIONS: This study confirmed that the toenail flap with distal phalangeal bone restored the second-degree thumb defect without destroying the main functional structure of the sole. The biomechanical indices of the donor foot were basically restored to normal 6 months after the operation. Only the stress concentration area centred on the third metatarsal head, and the pain on the forefoot was induced after the operation. Discomfort, callus formation, metatarsal fasciitis, etc., can lead to fatigue fracture of the third metatarsal bone in severe cases, which requires further follow-up and observation. TRIAL REGISTRATION: Clinicaltrials.gov , NCT03879941; registered on 10 March 2019, retrospectively.

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