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1.
Dev Comp Immunol ; 102: 103468, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31430488

RESUMO

Insects, which lack the adaptive immune system, have developed sophisticated innate immune system consisting of humoral and cellular immune responses to defend against invading microorganisms. Non-self recognition of microbes is the front line of the innate immune system. Repertoires of pattern recognition receptors (PRRs) recognize the conserved pathogen-associated molecular patterns (PAMPs) present in microbes, such as lipopolysaccharide (LPS), peptidoglycan (PGN), lipoteichoic acid (LTA) and ß-1, 3-glucans, and induce innate immune responses. In this review, we summarize current knowledge of the structure, classification and roles of PRRs in innate immunity of the model organism Drosophila melanogaster, focusing mainly on the peptidoglycan recognition proteins (PGRPs), Gram-negative bacteria-binding proteins (GNBPs), scavenger receptors (SRs), thioester-containing proteins (TEPs), and lectins.

2.
J Alzheimers Dis ; 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31594221

RESUMO

Apolipoproteins (APOs) have been implicated in the pathogenesis of Alzheimer's disease (AD). In the present study, we aimed to investigate if patterns of cerebrospinal fluid (CSF) APOs (APOA-I, APOC-III, APOD, APOE, APOH, and APOJ) levels are associated with changes over time in cognition, memory performance, neuroimaging markers, and AD-related pathologies (CSF Aß42, t-tau, and p-tau) in non-demented older adults. At baseline, a total of 241 non-demented older adults with CSF APOs data was included in the present analysis. Hierarchical agglomerative cluster analysis including the six CSF APOs was carried out. Among non-demented older adults, we identified two clusters. Compare with the first cluster, the second cluster had higher levels of APOs in CSF. Additionally, the second cluster showed a more benign disease course, including slower cognitive decline and slower p-tau accumulation in CSF. Our data highlight the importance of APOs in the pathogenesis of AD.

3.
J Chem Phys ; 151(13): 134307, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31594345

RESUMO

We report experimental observations of aniline (A) cations and He2 + when aniline is doped into ionized helium droplets. Large droplets containing 108 atoms are bombarded by energetic electrons, resulting in more than one positive charge in one droplet. When aniline encounters the charged droplets, some are ionized via charge transfer, while others can remain neutral in the presence of He2 + when the mass-to-charge ratio (m/z) of the droplet is sufficiently large. Upon resonant excitation of the dopant An or An + (n ≥ 1), He2 + can be ejected. The excitation spectrum of He2 + becomes a juxtaposition of the spectra of An and An +. Moreover, an anticorrelation between the yields of He2 + and A+ is observed with increasing energies of the ionizing electrons. We attribute this result to the combined effect of reduction in m/z of the droplets and the different locations of He2 + and neutral An. Limited by the penetration depths of the ionizing electrons and further assisted by the Coulomb repulsion of coexisting cations, He2 + is located within 20 nm of the surface, while neutral An has an average position inside a large droplet. Upon resonant excitation of the interior An, He2 + is preferentially ejected. With increasing energies of the colliding electrons, the m/z of the droplets are reduced, leading to less effective charge shielding and more effective charge transfer, until ultimately, all He2 + can be neutralized to form A+.

5.
Chem Commun (Camb) ; 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31595892

RESUMO

Surface modification based on a photo-induced electron transfer (PET) reaction in a pyridinium-decorated MOF material was found to be effective in regulating adsorption capacity. The current system enables the adsorption behavior to be manipulated based on variable affinity toward guest molecules through the redistribution of charge population with the preservation of the original pore structure, which is different from the prevalent approaches depending on photoinduced changes in molecular configurations of the pore backbone.

6.
Am J Public Health ; 109(11): 1533-1534, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31577505
7.
J Org Chem ; 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31580081

RESUMO

Herein, an operationally simple and mild strategy to construct sulfenation of oxindoles with a series of thiols in the absence of transition metals was developed. This methodology provides an efficient way to directly form C-S bond at C-3 position of oxindoles under mild reaction conditions with a cheap and common solvent and base in moderate to good yields.

8.
Medicine (Baltimore) ; 98(39): e17365, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31574884

RESUMO

RATIONALE: Periorbital cellulitis or an orbital abscess caused by acute sinusitis is a serious acute infectious disease. If not treated in time, serious complications may occur. PATIENT CONCERNS: A 16-year-old girl with a history of right-sided proptosis, periorbital swelling, chemosis, hypophasis, restricted ocular movement in the upward direction, and diminution of vision was referred to our institution. The clinic, computed tomography (CT) and magnetic resonance imaging (MRI) examination indicate right orbital abscess in the upper quadrant and sinusitis. DIAGNOSES: She was diagnosed with orbital abscess, acute sinusitis. INTERVENTIONS: She underwent medical management, transnasal endoscopic surgery and then ultrasound-guided fine needle aspiration (FNA) and catheter drainage. OUTCOMES: She was completely cured without any complications or sequelae. LESSONS: Performance of surgical drainage in a timely manner and administration of effective antibiotic treatment according to bacterial culture can reduce the complications of orbital abscesses. Ultrasound-guided FNA and catheter drainage is a safe, simple, and effective method for the treatment of orbital abscess.


Assuntos
Abscesso/cirurgia , Drenagem/métodos , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Doenças Orbitárias/cirurgia , Sinusite/cirurgia , Abscesso/microbiologia , Doença Aguda , Adolescente , Cateteres , Drenagem/instrumentação , Feminino , Humanos , Doenças Orbitárias/microbiologia , Sinusite/microbiologia
9.
ISA Trans ; 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31570163

RESUMO

With the rapid development of micro-spacecraft, miniaturization has become a key problem in attitude control. As an angular momentum exchange actuator, a single reaction sphere can generate multi-DOF output torques and satisfy the requirement of three-axis attitude control. This enables it to be a potential alternative for micro-spacecraft attitude control system. Categorized by the driving principles, the various design techniques of reaction spheres are firstly reviewed, including the spherical motor based and the multi-driving-wheels based. Their advantages and disadvantages are summarized. In order to realize the closed-loop control of the reaction sphere, the techniques of measuring the speed and orientation of the reaction spheres are subsequently reviewed. These include rotary encoders or gyroscope with gimbal guideway, photoelectric encoding ring, machine vision, Hall sensor, color sensor and piezoelectric sensor. By promoting the popularization of the concept of reaction spheres, it is expected to provide new ideas for the miniaturization design and attitude control of micro-spacecraft.

10.
Inorg Chem ; 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31573192

RESUMO

The rational design of binuclear Au(I)-Au(I), Au(II)-Au(II), and Au(I)-Au(III) complexes requires an understanding of how the redox states interconvert. Herein, the electrochemical interconversion of the three oxidation states I, II, and III is reported on the voltammetric (cyclic and rotating disk electrode) time scales for binuclear gold complexes containing C6F4PPh2 as a ligand, to demonstrate for the first time formation of a binuclear Au(II)-Au(II) from a Au(I)-Au(III) complex. Results are supported by bulk electrolysis and coulometry with reaction products being identified by 31P NMR and UV-vis spectroscopy. All electrochemical processes involve an overall two-electron charge-transfer process with no one-electron intermediate being detected. Importantly, the kinetically rather than thermodynamically favored isomer [Au2IIX2(µ-2-C6F4PPh2)2] is formed on redox cycling of [XAuI(µ-2-C6F4PPh2)(κ2-2-C6F4PPh2)AuIIIX] (X = Cl, ONO2). Finally, a mechanism is proposed to explain the simultaneous change of coordination of the chelating carbanionic ligand to bridging mode and interconversion of oxidation states in binuclear gold complexes.

11.
Dalton Trans ; 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31591633

RESUMO

B/N anionic aminoborane linear or branched chain complexes, [BH3(NH2BH2)nH]- (n = 1, 2, and 3) and [BH(NH2BH3)3]-, have been synthesized through the controlled reactions of ammonia borane (NH3BH3) with NaH by adjusting the reactant ratios and reaction temperatures. The possible reaction mechanisms were elucidated based on experimental and theoretical studies.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31592630

RESUMO

Acidic proton exchange membrane water electrolysis is a prospective energy conversion technology for future hydrogen production. However, its wide application is limited by the excessive dependence of oxygen evolution reaction on precious metals at anode. To address this issue, herein, we report a class of IrM (M = Ni, Co, Fe) catalysts with diluted Ir content fabricated via a eutectic-directed self-templating strategy. Manipulated by the eutectic reaction and dealloying inheritance effect, the IrM catalysts show a unique network structure composed of intertwining nanoporous nanowires. The catalytic activities of IrM nanowires show a transition metal dependent feature, among which IrNi delivers the best activity with an exceptionally low overpotential to drive 10 mA cm-2 (283 mV) and a high mass activity at 1.53 V vs. RHE (0.732 A mg-1). Such performance represents a major leap forward compared to that of commercial IrO2 and most of state-of-the-art Ir-based acidic catalysts towards oxygen evolution reaction. First-principles calculations indicate that the 3d transition metal dependent catalytic activity of IrM electrocatalysts is related to ligand effect, wherein the negative shift of Ir d-band center after alloying can effectively weaken the adsorption of reaction intermediates.

13.
Anal Chem ; 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31592647

RESUMO

Herein, we develop a route to prepare bifunctional plasmonic-fluorescent quantum dot-gold (QD-Au) hybrid nanoprobes by use of enzymatic reactions. Two bio-enzymes, glucose oxidase (GOx) and alkaline phosphatase (ALP) were chosen for the enzymatic preparation of core-satellite or core-shell type CdSe/ZnS@Au hybrid nanostructures. The enzymatic products, H2O2 and L-Ascorbic acid, of the two enzymes were exploited as mild reducing agents for controlled Au deposition on QD surfaces. The polymer multilayers by layer-by-layer assembly were used to adjust the separation between QD core and plasmonic Au, which can effectively reduce the quenching effect of the Au on QDs. The as-prepared QD@Au hybrid nanostructures are excellent dual-modality imaging nanoprobes, and can be used for fluorescence and dark-field scattering dual-imaging of MCF-7 cells. More importantly, the two enzymatic reaction systems can be explored for sensitive and selective detection of glucose and alkaline phosphatase, respectively, by monitoring the fluorescence spectra change of QD@Au hybrid nanoparticles, which is very useful for the glucose- and ALP-related disease diagnosis.

14.
Nat Commun ; 10(1): 4458, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31575867

RESUMO

The use of anion redox reactions is gaining interest for increasing rechargeable capacities in alkaline ion batteries. Although anion redox coupling of S2- and (S2)2- through dimerization of S-S in sulfides have been studied and reported, an anion redox process through electron hole formation has not been investigated to the best of our knowledge. Here, we report an O3-NaCr2/3Ti1/3S2 cathode that delivers a high reversible capacity of ~186 mAh g-1 (0.95 Na) based on the cation and anion redox process. Various charge compensation mechanisms of the sulfur anionic redox process in layered NaCr2/3Ti1/3S2, which occur through the formation of disulfide-like species, the precipitation of elemental sulfur, S-S dimerization, and especially through the formation of electron holes, are investigated. Direct structural evidence for formation of electron holes and (S2)n- species with shortened S-S distances is obtained. These results provide valuable information for the development of materials based on the anionic redox reaction.

15.
Am J Hum Genet ; 105(4): 803-812, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31564438

RESUMO

Concurrent hearing and genetic screening of newborns is expected to play important roles not only in early detection and diagnosis of congenital deafness, which triggers intervention, but also in predicting late-onset and progressive hearing loss and identifying individuals who are at risk of drug-induced HL. Concurrent hearing and genetic screening in the whole newborn population in Beijing was launched in January 2012. This study included 180,469 infants born in Beijing between April 2013 and March 2014, with last follow-up on February 24, 2018. Hearing screening was performed using transiently evoked otoacoustic emission (TEOAE) and automated auditory brainstem response (AABR). For genetic testing, dried blood spots were collected and nine variants in four genes, GJB2, SLC26A4, mtDNA 12S rRNA, and GJB3, were screened using a DNA microarray platform. Of the 180,469 infants, 1,915 (1.061%) were referred bilaterally or unilaterally for hearing screening; 8,136 (4.508%) were positive for genetic screening (heterozygote, homozygote, or compound heterozygote and mtDNA homoplasmy or heteroplasmy), among whom 7,896 (4.375%) passed hearing screening. Forty (0.022%) infants carried two variants in GJB2 or SLC26A4 (homozygote or compound heterozygote) and 10 of those infants passed newborn hearing screening. In total, 409 (0.227%) infants carried the mtDNA 12S rRNA variant (m.1555A>G or m.1494C>T), and 405 of them passed newborn hearing screening. In this cohort study, 25% of infants with pathogenic combinations of GJB2 or SLC26A4 variants and 99% of infants with an m.1555A>G or m.1494C>T variant passed routine newborn hearing screening, indicating that concurrent screening provides a more comprehensive approach for management of congenital deafness and prevention of ototoxicity.

16.
J Diabetes Investig ; 2019 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-31587459

RESUMO

We describe here a case of nivolumab-induced type 1 diabetes, which developed within 9 days of treatment. The case highlights the importance of frequent monitoring of glucose after initiation of nivolumab treatment.

17.
Biosci Biotechnol Biochem ; : 1-10, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31483222

RESUMO

Large numbers of miRNAs are found in biofluid exosomes. We isolated ~50-200 nm diameter exosomes from four types of porcine biofluid (urine, plasma, semen, and bile) using serial centrifugation and ultracentrifugation procedures. A total of 42.15 M raw data were generated from four small RNA libraries. This produced 40.17 M map-able sequences, of which we identified 204 conserved miRNAs, and 190 novel candidate miRNAs. Furthermore, we identified 34 miRNAs specifically expressed in only one library, all with well-characterized immune-related functions. A set of five universally abundant miRNAs (miR-148a-3p, miR-21-5p, let-7f-5p, let-7i-5p, and miR-99a-5p) across all four biofluids was also found. Function enrichment analysis revealed that the target genes of the five ubiquitous miRNAs are primarily involved in immune and RNA metabolic processes. In summary, our findings suggest that porcine biofluid exosomes contain a large number of miRNAs, many of which may be crucial regulators of the immune system.

19.
Respiration ; : 1-10, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31509823

RESUMO

Massive hemoptysis is one of emergency and critical diseases of the respiratory system. The definition of massive hemoptysis has always been different in the literature, which often depends on the quantitative estimation of the amount of hemoptysis, such as the amount of hemoptysis being in the range of 300-600 mL within 24 h, or hemoptysis more than 3 times within 1 week. Each amount of hemoptysis that is greater than 100 mL can be considered as massive hemoptysis, but the amount of hemoptysis is difficult to accurately estimate. Therefore, massive hemoptysis can be defined as any life-threatening hemoptysis and any hemoptysis that may cause airway obstruction and asphyxia. Massive hemoptysis accounts for approximately 5% of all hemoptysis cases and usually indicates the presence of a potentially severe respiratory or systemic disease. The mortality rate of massive hemoptysis is about 6.5-38%. The cause of death is generally shock caused by airway obstruction or excessive bleeding, and asphyxia is the main cause of death. At present, due to insufficient understanding of massive hemoptysis, there are limited technical means in the etiological diagnosis and untimely or improper treatment, resulting in high mortality of massive hemoptysis. Therefore, the diagnosis and treatment of massive hemoptysis needs to be standardized.

20.
Colloids Surf B Biointerfaces ; 183: 110452, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31473409

RESUMO

Currently used Gd-based and Mn-based small molecular MRI contrast agents fail to meet the requirements for the long-term monitoring, and the potential safety risk under high administration dose or repeat dosing needs to be considered. In the present study, a biocompatible macromolecular magnetic resonance imaging (MRI) contrast agents based on O-carboxymethyl chitosan (CMCS), CMCS-(Mn-DTPA)n was designed and synthesized. The relaxivity of CMCS-(Mn-DTPA)n is approximately 3.5 and 5.5 times higher than that of Gd-DTPA and Mn-DPDP in aqueous solution, respectively. The MRI signal intensity in the kidney and liver of Sprague Dawley (SD) rats is significantly increased at a dose of 0.03 mM Mn/kg b.w. CMCS-(Mn-DTPA)n accompanied by a long effective imaging window. According to in vitro studies, CMCS-(Mn-DTPA)n exhibits good cellular and blood biocompatibility at the dose necessary for MRI imaging. Based on the results from in vivo studies, manganese (Mn) is completely excreted from SD rats within ten days after administration and does not exert a pathological effect on the liver. CMCS-(Mn-DTPA)n represents a potentially novel MRI contrast agent due to its excellent relaxivity, long effective imaging window and good biocompatibility.

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