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1.
Artigo em Inglês | MEDLINE | ID: mdl-32401477

RESUMO

A high-quality precursor solution is essential for the fabrication of hybrid perovskite solar cells. This article reports a simple and efficient method for preparing a high-quality concentrated solution of methylammonium triiodoplumbate (MAPbI3) in N,N-dimethylformamide (DMF) by using MAPbI3 crystals instead of conventional lead iodine and methylammonium iodine blend. The MAPbI3 concentration of the precursor solution is easily and accurately adjusted from 0 up to 1.64 M. An investigation of the dissolution process of the MAPbI3 crystals reveals that the concentrated solution of MAPbI3 in DMF is metastable, and the transition from the concentrated solution to solvated intermediate MAPbI3·DMF determines the solubility of MAPbI3 in DMF. The high purity and precise stoichiometric ratio of the crystals eliminate the possible impurities that initialize the transition to MAPbI3·DMF and consequently suppress the transition and increase the stability of the concentrated solution. MAPbI3 films with different thicknesses up to 800 nm are prepared with the conventional film fabrication technique, and the highest power conversion efficiency of 20.7% is achieved on corresponding solar cells. This newly developed method for preparing a concentrated precursor solution can be easily combined with other fabrication techniques for further development of industrial-scale manufacture of solar cells.

2.
Medicine (Baltimore) ; 99(18): e20102, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32358399

RESUMO

This study aimed to improve the diagnostic accuracy of abdominal unicentric Castleman's disease (UCD) by retrospectively summarizes the relatively specific imaging features of UCD.This study retrospectively collected fifteen patients with abdominal UCD confirmed by pathology. All patients were underwent ultrasound (US), computed tomography (CT), or magnetic resonance imaging (MRI) examination. The imaging findings of UCDs were analyzed by senior radiologists.Fifteen patients included 7 males and 8 females, aged 30 to 68 years old, with an average age of 51.73 ±â€Š13.57. In the 15 cases, 7 were located around the mesentery, 4 were located in the retroperitoneal space, and 4 in the liver. Fifteen cases contained solid masses, of which 13 had clear margins and 2 had blurred margins. The size of the mass ranged from 1.5 to 14.2 cm, with an average of 6.49 ±â€Š4.16 cm. US showed that 9 lesions were presented with hypo-echogenicity while 5 lesions presented with hyper-echogenicity spots. Unenhanced CT showed that the lesions were comprised of soft tissue while calcified lesions were found in 10 of the cases (66.67%, 10/15). T1-weighted imaging (T1WI) suggested the lesions as iso/hypo-signal, and mildly hyper-signal on T2-weighted imaging (T2WI). Diffusion-weighted imaging (DWI) showed different degrees of hyper-signal. Contrast-enhanced US and CT/MRI showed obvious enhancement at the arterial phase in 12 cases (85.71%, 12/14), most of which (50%, 7/14) showed continuous enhancement at the delayed phase. Feeding vessel could be seen within, or around the lesion in 5 cases (35.71%, 5/14).The study suggests that abdominal UCD commonly manifests as well-defined, homogeneous, solid, and hypervascular masses. Calcification and the presence of feeding vessel in the tumors are relatively specific features of abdominal UCD.


Assuntos
Abdome/diagnóstico por imagem , Abdome/patologia , Hiperplasia do Linfonodo Gigante/diagnóstico por imagem , Hiperplasia do Linfonodo Gigante/patologia , Adulto , Idoso , Hiperplasia do Linfonodo Gigante/diagnóstico , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Ultrassonografia
3.
Cell Mol Biol (Noisy-le-grand) ; 66(2): 87-92, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32415932

RESUMO

Cerebral infarction is an acute cerebrovascular disease caused by abnormal blood circulation in the brain. In the present study, we investigate the effect of astragaloside IV on cognitive dysfunction in cerebrally infarcted rats via transforming growth factor-ß (TGF-ß) / Smad signaling pathway. For this purpose, 45 rats were divided into three groups including astragaloside, model, and control. 30 of 45 healthy adult male SD rats were randomly selected to establish an acute cerebral infarction model. 15 modeled rats were enrolled as a model and astragaloside group, and another 15 rats as a blank control group. The rats in the astragaloside group were fed with astragaloside IV according to 1.08 g/kg body weight, and those in the blank group and model group were given matching normal saline. The levels of TGF-ß, Smad1, Smad3 and Smad7 of TGF-ß/Smad signaling transduction pathway at T0 (week 0), T1 (week 3) and T2 (week 6) were determined by enzyme-linked immunosorbent assay (ELISA). The modified neurological severity score (mNSS) was used to evaluate the improvement of cognitive dysfunction in rats. The mNSS of rats with cerebral infarction in the astragaloside group was lower than that in the control group and model group (P< 0.05). While the levels of TGF-ß, Smad1, Smad3 and Smad7 in the astragaloside group were higher than those in the control group and model group (P< 0.05). Astragaloside IV plays an important role in improving cognitive dysfunction in rats with cerebral infarction while affecting the levels of TGF-ß, Smad1, Smad3 and Smad7 and activating TGF-ß / Smad signaling pathway.

4.
Sci Total Environ ; 724: 138375, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32408470

RESUMO

Microplastic pollution in global marine environments has attracted significant concerns; however, the environmental factors that influence the distribution and characteristics of microplastics are still unclear. In this study, 100 L of surface seawater samples collected from 16 different stations of the South Yellow Sea in January, April, and August 2018 were analyzed to investigate the relationship between spatio-temporal distribution of microplastics and environment variables. Results showed that the abundance of microplastics in January (6.5 ± 2.1 items/L) was higher than that in April (4.9 ± 2.1 items/L) and August (4.5 ± 1.8 items/L). On the whole, 78% of the total microplastics were <500 µm, ~90% were fibers, 73.2%-81.7% were transparent, and the two most abundant polymer types were polyethylene and polypropylene. The highest variability of microplastic characteristics (colour, size, and shape) and composition were observed in August, thereby showing the apparent features of terrestrial sources of microplastic pollution. Principal components analysis distinguished the spatio-temporal distribution of the microplastics, and significant difference in plastic sizes was found between microplastics in January and those in the other two months, which could be attributed to the Yellow Sea Warm Current and/or winter monsoon. Additionally, the abundance of microplastics, especially small-sized microplastics (<500 µm), was positively correlated with seawater salinity. These results suggest that microplastic pollution in surface waters of the South Yellow Sea varies with seasons owing to differences in the terrestrial sources and marine hydrological dynamics.

5.
Org Biomol Chem ; 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32441285

RESUMO

An efficient sulfide-catalyzed [2 + 1] annulation of para-quinone methides (p-QMs) with diverse bromides has been achieved. This catalytic strategy provides an efficient and straightforward protocol for accessing a variety of spiro-cyclopropanyl-cyclohexadienone compounds in good to excellent yields (64% to 96% yields) with outstanding diastereoselectivities (>20 : 1 dr), displaying good functional group tolerance as well as gram-scale capacity.

6.
Eur J Pharmacol ; : 173213, 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32450176

RESUMO

Galectins are carbohydrate-binding proteins, and their importance in renal diseases of diverse etiology has been documented. Amongst different galectins, the role of galectin-3 in the pathophysiology of renal diseases has been well documented. There is an increase in galectin-3 in the circulation as well as on the kidneys in chronic kidney disease patients. The increase in galectin-3 is negatively correlated with a decrease in renal function and overall survival rate. The preclinical studies also correlate the increase in galectin-3 levels with renal dysfunction. Accordingly, scientists have exploited galectin-3 as a potential pharmacological target to improve renal functions in different preclinical models of renal injury. Apart from galectin-3, there have been few studies documenting the role of galectin-1, 8, and 9 in renal diseases. The role of galectin-1 is not clearly identified, and there have been conflicting reports regarding its role in renal diseases. Galectin-8 and 9 impart renoprotective effects as per clinical and preclinical studies, respectively. The present review discusses the role of different galectins in renal diseases of diverse etiology.

7.
Int J Biol Macromol ; 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32450325

RESUMO

Magnesium phosphate cement (MPC) can be injected to form an in situ scaffold to repair bone defects. Here we synthesized novel injectable bioactive cements (CMPCs) by incorporating different ratios of carboxymethyl chitosan (CMC, 0-10%) into MPC. The physiochemical properties, compositions, and microstructures of CMPCs were evaluated. The in vitro cellular responses of pre-osteoblast MC3T3-E1 cells to CMPCs including adhesion, proliferation, and differentiation were quantified and the underlying cellular mechanisms investigated. CMPCs had longer setting times and lower setting temperatures. CMPC injectability was enhanced by the addition of CMC. The CMPC containing 5% CMC had the highest compressive strength and washout resistance. CMPCs had a more neutral pH compared to MPC at four weeks. Furthermore, CMPC samples showed similar degradability and Mg2+ release to MPC in Tris-HCl buffer. Osteoblasts (MC3T3-E1) showed significantly greater adherence, proliferation, and differentiation on CMPC specimens than on MPC. Finally, CMPCs effectively increased the adsorption of fibronectin and activated integrin signaling as indicated by enhanced FAK and ERK phosphorylation. Our novel CMPC composites have improved physicochemical properties and cellular responses and represent a promising material for bone regeneration.

8.
Geriatr Gerontol Int ; 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32432835

RESUMO

AIMS: This study examined the effects of the starting position, distance and ending point on walking speed in older adults with both the usual and maximum walking speeds. METHODS: In total, 101 older community-dwellers aged between 60 and 74 years were included in this cross-sectional study. Participants were instructed to walk two distances (i.e., 10 and 25 m) at usual and maximum speeds twice. The paired t-test was used to examine the effects of starting positions (static start vs. dynamic start) and ending points (known vs. unknown ending point) on walking speed. Analysis of variance was used to explore walking speed differences among 4, 6, 8, 10, 15, 20 and 25 m walking tests. RESULTS: Differences in walking speed between static start and dynamic start became larger with a decrease in the walking distance (Cohen's d: 4 m > 6 m > 10 m), and differences were larger in tests at the maximum walking speed (Cohen's d = 0.28-0.85) compared with those at usual walking speed (Cohen's d = 0.21-0.67). The walking speed increased with distance, but no significant changes were found among 10, 15, 20 and 25 m tests at the usual speed. Trivial speed differences were observed in walking speed between known (mean = 1.23-1.82 m/s) and unknown ending points (mean = 1.27-1.86 m/s; Cohen's d < 0.20). CONCLUSIONS: Test parameters, particularly the starting position and walk distance, do influence walking speed measured in the short-distance walking speed test among older adults. Geriatr Gerontol Int ••; ••: ••-•• Geriatr Gerontol Int 2020; ••: ••-••.

9.
Sci Rep ; 10(1): 6913, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32313123

RESUMO

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

10.
Environ Int ; 139: 105724, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32305744

RESUMO

Crude oil could affect certain critical microbial processes of nitrogen cycling (N-cycling) in coastal sediments, and disturb the nitrogen balance. However, the understanding of the effects of crude oil on coastal sediments N-cycling under human disturbance was still limited. In this study, two sediments (named SY and HB with heavy and slight pollution, respectively) were sampled from Hangzhou Bay, China. After an incubation with exposure to different amounts of crude oil in above two sediments for 30 days, we found that crude oil affected microbial N-cycling in multiple levels. Potential rate measurements revealed that crude oil stimulated potential denitrification and N2O emissions in both sediments, which showed a higher influence on denitrification rates in higher concentration of oil. Quantitative PCR revealed that crude oil greatly increased abundances of bacterial and archaeal 16S rRNA genes and N-cycling genes (nirS, nosZ, nrfA, part of AOA and AOB amoA). On the other hand, only a few genes (16S rRNA and nrfA) showed higher transcriptional activities in oil-addition treatments. Results about relative changes of N-cycling genes revealed that the variations of N-cycling genes in oil-addition treatments were related to sediment types but not crude oil concentrations, and the genes in HB were more sensitive to crude oil than SY. Network analysis of N-cycling genes found that crude oil decreased the complexity of N-cycling gene networks in SY, while increased complexity in HB, and led to more competition among N-cycling microbes. Our findings help to look into the effects of crude oil on key N-cycling processes, and improve the understanding of the interactions among N-cycling under crude oil contamination.

11.
Zhongguo Zhong Yao Za Zhi ; 45(2): 267-273, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-32237308

RESUMO

In this study, the texture analyzer acupuncture pressure sensor was used to objectively characterize the "herb soaking with exact amount of water" for moistening process of ginseng. The single factor rotation experiment was used to investigate the effects of puncture speed, puncture depth and puncture site on puncture force and work. According to ginseng processing method in Chinese Pharmacopoeia, ginseng medicinal materials with diameters of about 1 cm and 2 cm were selected, and puncture experiments were carried out at the set measurement time to determine the hardness, work and water absorption of the ginseng moistening process. The endpoint threshold for the ginseng softening process was determined and verified. To reflect the actual internal conditions of the ginseng softening process, the puncture depth was preferably 70%, and the puncture speed was 30 mm·min~(-1). In the ginseng moistening process, the softening hardness and the puncture work were in accordance with the first-order kinetic equation y=a×exp(-k×x). The 0 h initial hardness a of 1 cm and 2 cm ginseng herbs were 289.8 N and 1 227 N, and the rate constants K were 0.149 4 N·h~(-1) and 0.100 7 N·h~(-1), respectively. After the ginseng was completely softened, the force required for puncture was 10 N, which can be used as the standard for "drug penetration". At this time, the water absorption rate of ginseng was 70%-100%. The softening time of ginseng with a diameter of 1 cm was about 20-22 h, and the softening time of ginseng with a diameter of 2 cm was about 40-46 h. A needle-type pressure sensor was used to accurately determine the end point of the softening process of ginseng and reduce the loss of active ingredients. The study results provide reference for the softening process kinetics and the process intelligent monitoring of other dried roots and rhizomes.

12.
Zhongguo Zhong Yao Za Zhi ; 45(4): 923-931, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32237495

RESUMO

With the widespread use of traditional Chinese medicine(TCM) and the integration of TCM and western medicine, drug-drug interaction(DDI) is considered as a major cause of therapeutic failures and side effects. Cytochrome P450 enzymes(CYPs) are responsible for large number of drug metabolism. CYP3 A4 and CYP2 D6, two important CYP isoforms, are responsible for about 80% drug metabolism of CYPs super family. The inhibition of CYPs is likely to be the most common factor leading to adverse DDI. Therefore, it is of great significance to predict potential CYP3 A4 and CYP2 D6 inhibitors to prevent the DDI. A fast and low-cost me-thod for calculating and predicting CYP inhibiting components was established in this paper, namely support vector machine(SVM) and molecular docking technology which are used to predict and screen drugs. Firstly, 12 qualitative models of two targets were established by using SVM, and the optimal model was selected to predict the compounds in traditional Chinese medicine database(TCMD). Then, molecular docking technology was used to establish docking model. By analyzing the key amino acids involved in drug-target interactions and combining with SVM model, potential inhibitors of CYP3 A4 and CYP2 D6 were found. From the computational results, astin D and epiberberine exhibited inhibition effect on CYP3 A4 and CYP2 D6, respectively. Astin D was only found in astins family from Aster tataricus, while epiberberine was considered to be the active constituent of Coptidis Rhizoma. Therefore, for the risk of DDI, extra attention should be paid to the source of these potential inhibitors, Asteris Radix et Rhizoma and Coptidis Rhizoma. This computational method provides technical support for discovering potential natural inhibitors of CYPs from Chinese herbs by using SVM and molecular docking model, and it is also helpful to recognize the CYPs-mediated DDI existing in TCM, providing research ideas for further pharmacovigilance of integrated therapy.

13.
J Neural Eng ; 2020 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-32340001

RESUMO

Repair and regeneration of peripheral nerve defect by engineered conduits has greatly advanced in the past decades while still facing great challenges. In this work, we fabricated a new highly oriented poly(L-lactic acid) (PLLA)/soy protein isolate (SPI) nanofibrous conduit (HO-PSNC) for nerve regeneration. Firstly, we observed that SPI could efficiently modify PLLA for the electrospinning of PLLA/SPI nanofibers with enhanced physical and biological properties. Incorporation of SPI decreased the fiber diameter and ductility of PLLA/SPI nanofibrous films (PSNFs), improved the tensile strength and surface wettability of PSNFs and increased the in vivo degradability of the PSNFs. When the hybrid ratio of SPI was 20 and 40%, PSNFs could efficiently promote neural cell extension and differentiation in vitro. Based on these data, 20% SPI (PSNF-20) was chosen for further investigation. Next, PSNF-20 with different fiber orientations (random/low orientation, medium, and high orientation, respectively) were developed and used for evaluating neural cell behaviors on the materials. Results revealed that the PSNF-20 with highly oriented nanofibers (HO-PSNF-20) or mediumly oriented nanofibers (MO-PSNF-20) showed a better performance in directing cell extension and enhancing neurite outgrowth. Finally, the highly oriented nanofibers conduits (HO-PSNC-20) were used to bridge sciatic nerve defect in rats with highly oriented PLLA and autografts as controls. HO-PSNC-20 exhibited a significant promotion in nerve regeneration and functional reconstruction compari.

14.
Lab Chip ; 20(9): 1531-1543, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32150176

RESUMO

One major challenge in current brain research is generating an integrative understanding of the brain's functions and disorders from its multiscale neuronal architectures and connectivity. Thus, innovative neurotechnology tools are urgently required for deciphering the multiscale functional and structural organizations of the brain at hierarchical scales from the molecular to the organismal level by multiple brain research initiatives launched by the European Union, United States, Australia, Canada, China, Korea, and Japan. To meet this demand, microfluidic chips (µFCs) have rapidly evolved as a trans-scale neurotechnological toolset to enable multiscale studies of the brain due to their unique advantages in flexible microstructure design, multifunctional integration, accurate microenvironment control, and capacity for automatic sample processing. Here, we review the recent progress in applying innovative µFC-based neuro-technologies to promote multiscale brain research and uniquely focus on representative applications of µFCs to address challenges in brain research at each hierarchical level. We discuss the current trend of combinational applications of µFCs with other neuro- and biotechnologies, including optogenetics, brain organoids, and 3D bioprinting, for better multiscale brain research. In addition, we offer our insights into the existing outstanding questions at each hierarchical level of brain research that could potentially be addressed by advancing microfluidic techniques. This review will serve as a timely guide for bioengineers and neuroscientists to develop and apply µFC-based neuro-technologies for promoting basic and translational brain research.

15.
Oncogene ; 39(17): 3427-3442, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32123313

RESUMO

Gastric cancer (GC) is one of the leading causes of cancer-related death worldwide. The role of the microorganisms in gastric tumorigenesis attracts much attention in recent years. These microorganisms include bacteria, virus, and fungi. Among them, Helicobacter pylori (H. pylori) infection is by far the most important risk factor for GC development, with special reference to the early-onset cases. H. pylori targets multiple cellular components by utilizing various virulence factors to modulate the host proliferation, apoptosis, migration, and inflammatory response. Epstein-Barr virus (EBV) serves as another major risk factor in gastric carcinogenesis. The virus protein, EBER noncoding RNA, and EBV miRNAs contribute to the tumorigenesis by modulating host genome methylation and gene expression. In this review, we summarized the related reports about the colonized microorganism in the stomach and discussed their specific roles in gastric tumorigenesis. Meanwhile, we highlighted the therapeutic significance of eradicating the microorganisms in GC treatment.

16.
Analyst ; 145(8): 3106-3115, 2020 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-32159201

RESUMO

Escherichia coli O157:H7 is a severe foodborne pathogen that causes lots of life-threatening diseases. In the search for a rapid, sensitive, portable and low-cost method to detect this pathogen, we developed a wax-printed paper-based enzyme-linked immunosorbent assay (P-ELISA) based on microfluidic paper-based analytical devices (µPADs), with the whole operation time being less than 3 h and only needing 5 µl samples for detection. The limit of detection (LOD) of E. coli O157:H7 reached 104 CFU ml-1, which is an order of magnitude higher than that of conventional ELISA (C-ELISA). The LOD in artificially contaminated beef samples is 1 CFU per 25 g after enriching the culture for 8 h. This method is superior to the molecular biology method in detection sensitivity and superior to C-ELISA and the national standard method in detection time and cost. Thus, the established P-ELISA method has good sensitivity, specificity and repeatability. It can be suitable for point-of-care testing without expensive and bulky instruments and can also provide a platform for detecting other pathogens, especially in areas that lack advanced clinical equipment.

17.
Ann Palliat Med ; 9(1): 19-29, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32005059

RESUMO

BACKGROUND: Acupuncture is a common alternative therapy for clinical treatment of insomnia. As the underlying mechanism is yet unclear, its efficacy is often considered as placebo effect. To clarify whether acupuncture treatment of insomnia is only due to its placebo effect, a systematic review and a meta-analysis were designed based on the comparison between acupuncture and sham acupuncture. METHODS: Four English (PubMed, Embase, Web of Science, and The Cochrane Library) and three Chinese (CNKI, VIP, and Wanfang) databases were searched, and the validity of the eligible studies was critically appraised. Thirteen eligible randomized controlled trials of moderate-to-high quality that employed polysomnography (PSG), actigraphy, or self-assessment sleep quality tools were included in the present study. A meta-analysis was conducted using a random-effects model with the Pittsburgh Sleep Quality Index (PSQI) as the primary outcome measure (911 adult patients, 13 trials) for trials investigating the effects of acupuncture as compared to the sham acupuncture. Then, a subgroup analysis was performed to detect the sources of heterogeneity, identify the selection of sham acupuncture methods and different crowd characteristics, and explore its contributions to the total score change of PSQI. RESULTS: Compared to the sham groups, acupuncture significantly decreased the PSQI score (P<0.0001). A subgroup analysis showed that the selection of sham acupuncture methods did not affect the results of PSQI. A subgroup of two trials with a total of 141 participants with major depressive disorder did not show any significant reductions in total PSQI scores (P=0.11). In addition, a significant difference was detected in the change of Insomnia Severity Index (ISI) scores (362 adult patients, 4 trials) between acupuncture and sham acupuncture (P<0.0001). The PSG and actigraphy data from acupuncture and the sham did not reveal any significant differences in the sleep structure changes. CONCLUSIONS: Acupuncture treatment of insomnia is efficacious, not because of its placebo effect. For the selection of sham acupuncture, both methods performed similarly in a clinical setting. Moreover, insomnia patients with major depression disorder were not recommended to use only acupuncture treatment.

18.
Org Biomol Chem ; 18(10): 1940-1948, 2020 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-32101246

RESUMO

A visible-light-promoted decarboxylative acyl radical acylation/cyclization cascade reaction of N-methacryloylbenzamides for accessing acylated isoquinoline-1,3(2H,4H)-dione derivatives was described. In this report, α-keto acids were used for generating acyl radicals and inducing radical acylations. This protocol features mild reaction conditions, operational practicality and a broad substrate scope.

19.
iScience ; 23(2): 100880, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32062456

RESUMO

The axon initial segment (AIS) cytoskeleton undergoes rapid and irreversible disruption prior to cell death after injury, and loss of AIS integrity can produce profound neurological effects on the nervous system. Here we described a previously unrecognized mechanism for ischemia-induced alterations in AIS integrity. We show that in hippocampal CA1 pyramidal neurons Nav1.6 mostly preserves at the AIS after disruption of the cytoskeleton in a mouse model of middle cerebral artery occlusion. Genetic removal of neurofascin-186 leads to rapid disruption of Nav1.6 following injury, indicating that neurofascin is required for Nav1.6 maintenance at the AIS after cytoskeleton collapse. Importantly, calcineurin inhibition with FK506 fully protects AIS integrity and sufficiently prevents impairments of spatial learning and memory from injury. This study provides evidence that calcineurin activation is primarily involved in initiating disassembly of the AIS cytoskeleton and that maintaining AIS integrity is crucial for therapeutic strategies to facilitate recovery from injury.

20.
Vet Microbiol ; 240: 108548, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31902494

RESUMO

Based on its causing ever-increasing heavy economic losses, Riemerella anatipestifer has been viewed as an important bacterial pathogen in the duck industry worldwide. However, the molecular mechanisms regarding its pathogenicity are poorly understood. In our previous study, we have built a random mutagenesis library of Riemerella anatipestifer CH3 using transposon Tn4351. In this study, we screened the library by determining bacterial median lethal dose in ducklings. A mutant strain showed about 376-fold attenuated virulence in comparison with the wild-type strain CH3 was obtained. Subsequently, the Tn4351 inserted gene was identified as M949_RS00050, which encodes a putative protein containing an outer membrane protein beta-barrel domain by genome walking and sequence analyses. Southern blot analysis indicated a single Tn4351 insertion in the CH3 chromosomal DNA. Inactivation of M949_RS00050 gene did not affect bacterial metabolic activity and the silver stained lipopolysaccharide pattern. However, the bacterial sensitivity to normal duck sera killing and bacterial hydrophobicity were dramatically enhanced in the M949_RS00050 gene inactivated mutant strain, compared to its wild-type strain CH3. Moreover, bacterial adherence and invasion abilities, bacterial capsular polysaccharide quantity, biofilm formation capacity and the bacterial virulence of the mutant strain were obviously decreased, compared to the wild-type strain CH3. Thus, our finding demonstrates that the M949_RS00050 gene functions on multiple bacterial biological properties and virulence in Riemerella anatipestifer.

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