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1.
J Nanosci Nanotechnol ; 20(3): 1873-1877, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492355

RESUMO

The structure and anisotropic magnetization of One-dimensional (1D) Nd/Co/PA66 coaxial nanocables prepared by a low cost physical infiltration and electrodeposition methods are investigated. The preparation of Co nanotubes, Co/PA66 two-layer nanotubes and Nd/Co/PA66 three-layer nanocales is described, respectively. The structure, chemical composition and magnetic properties of various nanomaterials were investigated. The results show that the magnetic properties were affected by the rare earth metal Nd and the structural properties. The residual magnetization ratio of Nd/Co/PA66 nanocables is the biggest due to the synergistic effect of Nd and Co. In addition, the magnetization processes of the nanostructure were discussed in detail. We believe that these methods may provide an idea for ferromagnetic alloys and permanent magnet material and suitable for future applications in perpendicular recording media.

3.
Microbiol Res ; 231: 126370, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31739261

RESUMO

The role of the gut microbiome in animal health has become increasingly evident. Although the structure of the gut microbiome of A. mellifera is well known, little is known about the dynamic change across different developmental stages. In this study, we explored the dynamic changes of the gut microbiota of A. mellifera at different developmental stages covering the whole life cycle using high-throughput 16S rRNA gene sequencing. The results indicated that the core (shared) gut microbiota changes significantly among different developmental stages. The diversity of the bacterial community in workers among different ages was significantly different. In addition, by comparing the core gut microbiota among different-aged workers, we found that newly emerged workers had fewer core microbiota. Three genera, Gilliamella, Frischella, and Snodgrassella, were significantly colonized at 1 day poste mergence (dpe); Lactobacillus, Bifidobacterium, Commensalibacter were significantly colonized at 3 dpe and significantly reduced with Gilliamella. Lactobacillus kunkeei and Bartonella were significantly colonized at 12 dpe and were significantly decreased with Lactobacillus helsingborgensis. Commensalibacter and Bifidobacterium were significantly decreased at 25 dpe, and Bacteroides, Escherichia-Shigella, and Porphyromonadaceae were significantly decreased between 19 and 25 dpe. Our results reveal the succession of the gut microbiota of workers from birth to senescence, which provides a theoretical basis for further exploring the roles of gut microbiota during different developmental stages.

5.
World J Surg Oncol ; 17(1): 192, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31718654

RESUMO

PURPOSE: This study aimed to explore the value of preoperative ultrasonography (US) in evaluating the peritoneal cancer index (PCI) of pseudomyxoma peritonei (PMP). METHODS: An ultrasound examination was performed on 59 patients with PMP before surgery, and the ultrasound PCI was evaluated. The accuracy of ultrasound PCI score was evaluated with the surgical PCI score as the gold standard. RESULTS: The preoperative ultrasound PCI was compared with the surgical PCI. The Spearman correlation coefficient of the total PCI score was 0.608 (P < 0.05). The difference in the Spearman correlation coefficient between the preoperative ultrasound PCI and the surgical PCI in areas 0-7 was statistically significant. (1) Among them, the total score and the correlation between 0-3 and 6 were higher. (2) Compared with the surgical PCI, overestimation (> 20%) was concentrated mainly in areas 2 and 4-8 for 2 points, and underestimation (< 20%) was concentrated mainly in areas 1, 3, 4, and 8 for 3 points. (3) The sensitivity and specificity of preoperative ultrasound for predicting the presence or absence of lesions were 85.7% and 50.0%, respectively. The sensitivity of LS 1, LS 2, and LS 3 was 31.7%, 48.2%, and 71.0%, respectively, and the specificity was 44.8%, 55.3%, and 58.8%, respectively. CONCLUSION: The ultrasound examination can be used to score the preoperative PCI, judge the severity, and predict the prognosis in patients with PMP.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31753507

RESUMO

The development of high-performance catalysts is of great importance in direct alcohol fuel cells. One dimensional nanorods catalysts are hopeful candidates as efficient alcohol electrocatalysis. However, it is desirable to precisely modulate the surface morphology of one dimensional nanorods nanocrystals to acquire better catalytic property. We effectively integrate properties of robust one dimensional nanorods, core@shell structure, and ternary nanoalloy into a new PtNiPd@Pt core@shell nanorods with high density bumps on the surface for potential better catalytic behaviors. Notably, those unique structures make the PtNiPd@Pt nanocrystals display favorable electrocatalytic performance towards methanol oxidation reaction. Specifically, the composition-optimized PtNi0.20Pd0.52 nanorods exhibit the highest methanol oxidation reaction specific activity of 18.01 mA cm-2 among PtNiPd@Pt catalysts in alkaline condition. The specific activity is 8.5 times higher than that of Pt/C catalysts. Moreover, electrochemical stability measurements also confirm the better reaction endurance of PtNi0.20Pd0.52 nanorods. Our work provides a reference to well tune the fine surface structure on one dimensional nanorods catalysts in the direction of superior electrocatalytic behaviors.

8.
J Transl Med ; 17(1): 358, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31690320

RESUMO

Following publication of the original article [1], the authors reported errors in Figures 2, 3 and Figure 3 'continued'.

9.
Adv Immunol ; 144: 65-85, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31699220

RESUMO

Adaptive lymphocytes express a panel of immunoreceptors on the cell surface. Phospholipids are the major components of cell membranes, but they have functional roles beyond forming lipid bilayers. In particular, acidic phospholipids forming microdomains in the plasma membrane can ionically interact with proteins via polybasic sequences, which can have functional consequences for the protein. We have shown that negatively charged acidic phospholipids can interact with positively charged juxtamembrane polybasic regions of immunoreceptors, such as TCR-CD3, CD28 and IgG-BCR, to regulate protein structure and function. Furthermore, we pay our attention to protein transmembrane domains. We show that a membrane-snorkeling Lys residue in integrin αLß2 regulates transmembrane heterodimer formation and integrin adhesion through ionic interplay with acidic phospholipids and calcium ions (Ca2+) in T cells, thus providing a new mechanism of integrin activation. Here, we review our recent progress showcasing the importance of both juxtamembrane and intramembrane ionic protein-lipid interactions.

10.
BMC Cancer ; 19(1): 1116, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31729963

RESUMO

OBJECT: Glioma is a common malignant tumours in the central nervous system (CNS), that exhibits high morbidity, a low cure rate, and a high recurrence rate. Currently, immune cells are increasingly known to play roles in the suppression of tumourigenesis, progression and tumour growth in many tumours. Therefore, given this increasing evidence, we explored the levels of some immune cell genes for predicting the prognosis of patients with glioma. METHODS: We extracted glioma data from The Cancer Genome Atlas (TCGA). Using the Cell-type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT) algorithm, the relative proportions of 22 types of infiltrating immune cells were determined. In addition, the relationships between the scales of some immune cells and sex/age were also calculated by a series of analyses. A P-value was derived for the deconvolution of each sample, providing credibility for the data analysis (P < 0.05). All analyses were conducted using R version 3.5.2. Five-year overall survival (OS) also showed the effectiveness and prognostic value of each proportion of immune cells in glioma; a bar plot, correlation-based heatmap (corheatmap), and heatmap were used to represent the proportions of immune cells in each glioma sample. RESULTS: In total, 703 transcriptomes from a clinical dataset of glioma patients were drawn from the TCGA database. The relative proportions of 22 types of infiltrating immune cells are presented in a bar plot and heatmap. In addition, we identified the levels of immune cells related to prognosis in patients with glioma. Activated dendritic cells (DCs), eosinophils, activated mast cells, monocytes and activated natural killer (NK) cells were positively related to prognosis in the patients with glioma; however, resting NK cells, CD8+ T cells, T follicular helper cells, gamma delta T cells and M0 macrophages were negatively related to prognosis in the patients with glioma. Specifically, the proportions of several immune cells were significantly related to patient age and sex. Furthermore, the level of M0 macrophages was significant in regard to interactions with other immune cells, including monocytes and gamma delta T cells, in glioma tissues through sample data analysis. CONCLUSION: We performed a novel gene expression-based study of the levels of immune cell subtypes and prognosis in glioma, which has potential clinical prognostic value for patients with glioma.

11.
Acta Neurol Scand ; 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31715011

RESUMO

OBJECTIVE: Increased permeability and changes in gut microbiota contributed to the pathogenesis of Alzheimer's disease (AD). Zonulin is a key modulator that regulates intestinal barrier function. Peripheral platelet alterations have been involved in AD pathology. C-type lectin-like receptor 2 (CLEC-2) is a receptor on the platelet surface for activation. The purpose of this study was to determine zonulin and CLEC-2 levels in mild cognitive impairment (MCI) and AD, and investigate the relationship between zonulin and CLEC-2. METHODS: In this study, CLEC-2 and zonulin levels were measured using ELISA assay in 110 AD patients, 110 MCI patients, and 110 non-demented control subjects. RESULTS: Increased CLEC-2 and zonulin levels were observed in MCI and AD patients. Furthermore, AD patients had higher CLEC-2 and zonulin levels compared with MCI patients. In addition, CLEC-2 levels were positively correlated with zonulin levels, after adjusting confounding factors (r = .592, P < .001). Multivariate analysis revealed that increased CLEC-2 and zonulin levels were significantly associated with reduced Mini-Mental State Examination (MMSE) score. CONCLUSIONS: C-type lectin-like receptor 2 is correlated with zonulin after adjusting confounding covariates. Moreover, increased CLEC-2 and zonulin are the significant factors for reduced MMSE score in MCI and AD. Further studies are needed.

12.
Mol Carcinog ; 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31763724

RESUMO

It is reported that black raspberry (BRB) anthocyanins could act as a potential chemopreventive agent for colorectal cancer (CRC). However, the underlying mechanism by which BRB anthocyanins inhibits the carcinogenesis of CRC cells has not been elucidated. The abnormal expression of microRNAs (miRNAs) that target important tumor suppressor genes is usually associated with CRC development. In this study, we explored whether BRB anthocyanins could affect the expression of certain miRNAs in an azoxymethane (AOM)/dextran sulphate sodium (DSS)-induced CRC mouse model and human CRC cell lines. miRNA microarray analysis was used to determine the differences in miRNA expression between AOM/DSS-induced mice fed with a diet supplemented without or with BRB anthocyanins. The expression of one particular miRNA, miR-483-3p, was found to decrease dramatically in AOM/DSS-induced mice that were fed with a diet supplemented with BRB anthocyanins. Subsequent quantitative real-time polymerase chain reaction and Western blot analyses showed that the reduced expression of miR-483-3p was accompanied by an increased expression of Dickkopf 3 (DKK3), a potential target of miR-483-3p as predicted by bioinformatic analysis. The protein and messenger RNA levels of DKK3 were significantly upregulated when the miR-483-3p level was reduced by a miR-483-3p-specific inhibitor, suggesting that DKK3 might be the target gene of miR-483-3p. In addition, the downstream factors of the DKK3 signaling pathway, which included Wnt/ß-catenin, also played a role in the miR-483-3p-mediated anticancer effect of BRB anthocyanins. Thus, miR-483-3p might be a potential target in BRB anthocyanin-mediated prevention of CRC.

13.
Medicine (Baltimore) ; 98(47): e17970, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31764802

RESUMO

Alzheimer disease (AD) is the most common neurodegenerative disease in the world. The relationship between AD and homocysteine (Hcy) is contradictory.A community-based investigation was conducted to find patients with AD in a vitamin B deficient population (≥55 years old) in Lüliang area in China. Venous blood samples were collected. Serum Hcy, folate, and vitamin B12 were measured. For each case, 4 controls were selected matched with age to evaluate the relationship between Hcy and AD.The crude prevalence of AD among people ages 55 years or older in this area was 8.60%. There were significant differences in serum Hcy and B12 between the case and control groups. We found that the higher level of serum Hcy was associated with a high risk of AD, and higher education level, higher folate and B12 concentration were protective factors to AD.Adjustment of diet structure and supplementation of folate and B12 may offer potential therapeutic measures in this area.

14.
Exp Mol Med ; 51(11): 142, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31757938

RESUMO

Hepatocellular carcinoma (HCC) is a major cause of cancer-related deaths, but its molecular mechanisms are not yet well characterized. Long noncoding RNAs (lncRNAs) play crucial roles in tumorigenesis, including that of HCC. However, the role of homeobox A11 antisense (HOXA11-AS) in determining HCC stem cell characteristics remains to be explained; hence, this study aimed to investigate the effects of HOXA11-AS on HCC stem cell characteristics. Initially, the expression patterns of HOXA11-AS and HOXA11 in HCC tissues, cells, and stem cells were determined. HCC stem cells, successfully sorted from Hep3B and Huh7 cells, were transfected with short hairpin or overexpression plasmids for HOXA11-AS or HOXA11 overexpression and depletion, with an aim to study the influences of these mediators on the self-renewal, proliferation, migration, and tumorigenicity of HCC stem cells in vivo. Additionally, the potential relationship and the regulatory mechanisms that link HOXA11-AS, HOXA11, and the Wnt signaling pathway were explored through treatment with Dickkopf-1 (a Wnt signaling pathway inhibitor). HCC stem cells showed high expression of HOXA11-AS and low expression of HOXA11. Both HOXA11-AS silencing and HOXA11 overexpression suppressed the self-renewal, proliferation, migration, and tumorigenicity of HCC stem cells in vivo, as evidenced by the decreased expression of cancer stem cell surface markers (CD133 and CD44) and stemness-related transcription factors (Nanog, Sox2, and Oct4). Moreover, silencing HOXA11-AS inactivated the Wnt signaling pathway by decreasing the methylation level of the HOXA11 promoter, thereby inhibiting HCC stem cell characteristics. Collectively, this study suggested that HOXA11-AS silencing exerts an antitumor effect, suppressing HCC development via Wnt signaling pathway inactivation by decreasing the methylation level of the HOXA11 promoter.

15.
Adv Drug Deliv Rev ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31759123

RESUMO

The CRISPR-Cas system initiated a revolution in genome editing when it was, for the first time, demonstrated success in the mammalian cells. Today, scientists are able to readily edit the genome, regulate gene transcription, engineer posttranscriptional events, and image nucleic acids using CRISPR-Cas-based tools. However, to efficiently transport CRISPR-Cas into target tissues/cells remains challenging due to many extra- and intra-cellular barriers, therefore largely limiting the applications of CRISPR-based therapeutics in vivo. In this review, we summarize the features of plasmid-, RNA- and ribonucleoprotein (RNP)-based CRISPR-Cas therapeutics. Then, we survey the current in vivo delivery systems. Finally, we specify the requirements for efficient in vivo delivery in clinical settings, and highlight both efficiency and safety for different CRISPR-Cas tools.

16.
BMC Med Genet ; 20(1): 182, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31727123

RESUMO

BACKGROUND: Majeed syndrome is a rare, autosomal recessive autoinflammatory disorder first described in 1989. The syndrome starts during infancy with recurrent relapses of osteomyelitis typically associated with fever, congenital dyserythropoietic anemia (CDA), and often neutrophilic dermatosis. Mutations in the LPIN2 gene located on the short arm of chromosome 18 have been identified as being responsible for Majeed syndrome. CASE PRESENTATION: We report an 8-month-old boy, who presented with recurrent fever, mild to moderate anemia, and severe neutropenia. Erythrocyte sedimentation rate and C-reactive protein were elevated. Molecular testing identified a paternal splicing donor site variant c.2327 + 1G > C and a maternal frameshift variant c.1691_1694delGAGA (Arg564Lysfs*3) in LPIN2. CONCLUSIONS: Only a few cases with LPIN2 mutation have been reported, mainly in the Middle East with homozygous variants. Our patient exhibited a mild clinical phenotype and severe neutropenia, different from previous reports.

17.
Artigo em Inglês | MEDLINE | ID: mdl-31727522

RESUMO

In this work, we developed a simple, effective fluorescence method to detect Hg2+ by inhibiting core-satellite assemblies of gold nanorods (AuNRs) and gold nanospheres (AuNPs). The fluorescence of Rhodamine 6G (Rh6G), which was simply mixed with the nanoassemblies, was efficiently quenched by the inner filter effect (IFE). When the heterogenous core-satellite nanostructures were assembled, the corresponding local surface plasmon resonance (LSPR) absorption shifts and broadens which results in the increase of the spectral overlap between the emission peak and the absorption band and more efficient energy transfer from Rh6G to nanoparticles. Fluorescence quenching efficiency is related to the size and number density of satellite nanoparticles. It is interesting that the AuNR-AuNP assemblies with the moderate size and high density of AuNPs have the best fluorescence quenching efficiency. In the presence of Hg2+, p-aminothiophenol (p-ATP) breaks away from the surface of AuNRs and competitively bounds to Hg2+, resulting in a low yield of the AuNR-AuNP assemblies, which further leads to the decrease of fluorescence quenching efficiency. Under the optimum conditions, the limit of detection (LOD) for Hg2+ was 0.18 nM, with an excellent linear response from 0.6 to 800 nM. Interference experiment and real samples detection indicate that these nanosensors endowed with higher sensitivity and selectivity for the detection of Hg2+ in the real samples. Compared with the conventional Hg2+ detection techniques, this method based on Hg2+ induced inhibition of core-satellite AuNR-AuNP assemblies has better performance and is suitable for the detection of Hg2+.

18.
Opt Express ; 27(22): 32746-32763, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31684481

RESUMO

We propose a hybrid structure where graphene is inserted to the interface of two one-dimensional photonic crystals (1D PCs). The two PCs are designed to have opposite topological properties, and at the interface, topological edge modes exist. The edge modes exist at both the fundamental frequency (FF) and the third harmonic (TH) frequency. This double resonant structure will enhance the nonlinear responses of graphene greatly, including Kerr nonlinearity and TH generation. We discuss these two kinds of nonlinearities both at terahertz (THz) and near-infrared (NIR) frequencies. The influence of Kerr nonlinearity on the resonant frequencies is considered, when we calculate the TH generation. At THz frequency, low-threshold bistability (about 8MW/cm2) is obtained and the TH generation efficiency of 2.5% is achieved with incident intensity of 10MW/cm2. At NIR frequency, the nonlinear conductivities of graphene are about 7 orders lower. Bistability is unlikely to happen with incident intensity below 1GW/cm2. The TH generation efficiency is only about 5×10-6 with incident intensity of 25MW/cm2. The proposed structure is more suitable to work as a low-threshold saturable absorber at NIR frequency. These results may be helpful both for a better understanding of graphene's nonlinear responses in a double resonant structure and for potential applications in THz nonlinear devices and NIR nanophotonics.

19.
Clin Chim Acta ; 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31678577

RESUMO

BACKGROUND: Nephronophthisis (NPHP) is an autosomal recessive cystic kidney disease that leads to renal failure in childhood or adolescence. NPHP and the related syndromes have been termed 'ciliopathies' because most NPHP gene products localize to the cilium or its associated structures. METHODS: Here, we report a 2-year and 11-month-old Chinese girl with end-stage renal disease (ESRD), severe anemia, thrombocytopenia and myocardial hypertrophy. We performed trio-whole-exome sequencing to identify the causative variant of this patient. RESULTS: We identified an unreported compound heterozygous mutation (c.2420dupT, p.Thr808Aspfs*2 and c.1973-1G > A) in ANKS6 in the proband. The frameshift mutation c.2420dupT of ANKS6 was inherited from the proband's unaffected father and the splicing mutation c.1973-1G > A of ANKS6 was inherited from the proband's unaffected mother. Homozygous mutation in ANKS6 leads to NPHP16 (OMIM#615382) and this is the first case with a compound heterozygous mutation in the NPHP16 gene. CONCLUSION: We have identified a patient with ANKS6 variants in the East-Asian population for the first time. This case report expands the clinical and genetic spectra of NPHP and emphasizes the usefulness of whole-exome sequencing for genetic diagnosis of kidney disease.

20.
J Bone Miner Res ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31693237

RESUMO

Jansen's metaphyseal chondrodysplasia (JMC) is a rare disease of bone and mineral ion physiology that is caused by activating mutations in the PTHR1. Ligand-independent signaling by the mutant receptors in cells of bone and kidney results in abnormal skeletal growth, excessive bone turn-over, and chronic hypercalcemia and hyperphosphaturia. Clinical features further include short-stature, limb deformities, nephrocalcinosis and progressive losses in kidney function. There is no effective treatment option available for JMC. In previous cell-based assays, we found that certain N-terminally truncated PTH and PTHrP antagonist peptides function as inverse agonists and thus can reduce the high rates of basal cAMP signaling exhibited by the mutant PTHR1s of JMC in vitro. Here we explored whether one such inverse agonist ligand, [Leu11 ,dTrp12 ,Trp23 ,Tyr36 ]-PTHrP(7-36)NH2 (IA), can be effective in vivo and thus ameliorate the skeletal abnormalities that occur in transgenic mice expressing the PTHR1-H223R allele of JMC in osteoblastic cells via the collagen-1α1 promoter (C1HR mice). We observed that after two weeks of twice-daily injection and relative to vehicle controls, the IA analog resulted in significant improvements in key skeletal parameters that characterize the C1HR mice, as it reduced the excess trabecular bone mass, the bone marrow fibrosis and the levels of bone turnover markers in blood and urine. The overall findings provide proof-of-concept support for the notion that inverse agonist ligands targeted to the mutant PTHR1 variants of JMC can have efficacy in vivo. Further studies of such PTHR1 ligand analogs could help open paths towards the first treatment option for this debilitating skeletal disorder. This article is protected by copyright. All rights reserved.

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