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1.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(10): 965-969, 2019 Oct 10.
Artigo em Chinês | MEDLINE | ID: mdl-31598937

RESUMO

OBJECTIVE: To explore the genetic basis for a family with non-syndromic autosomal recessive deafness. METHODS: The proband and her parents were subjected to physical and audiological examinations. With genomic DNA extracted from peripheral blood samples, next-generation sequencing was carried out using a panel for deafness genes. Suspected mutation was validated by Sanger sequencing and qPCR analysis of her parents. RESULTS: The proband presented bilateral severe sensorineural hearing loss at three days after birth. Her auditory threshold was 110-120 dBnHL but with absence of vestibular and retinal symptoms. Her brother also had deafness but her parents were normal. No abnormality was found upon physical examination of her family members, while audiological examination showed no middle ear or retrocochlear diseases. Next-generation sequencing identified compound heterozygous mutations of the MYO7A gene, including a previously known c.462C>A (p. Cys154Ter) and a novel EX43_46 Del, which were respectively derived from her mother and father. CONCLUSION: The compound heterozygous mutations of the MYO7A gene probably underlie the disease in this family. Our findings has enriched the mutation spectrum for non-syndromic autosomal recessive deafness 2.

2.
Chemosphere ; 236: 124841, 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31545182

RESUMO

Hydrochars derived from municipal sewage sludge was analyzed for its feasibility for value-added recycling. Results of carbon content and elemental composition suggested that the hydrochars might not be comparable with pyrochars regarding to the carbon sequestration, long-term stability and fuel quality. Application as soil amendment would be a better approach for hydrochar utilization. To examine the potential benefits and risks of that, the total and available content of nutrients (i.e. N, P, and K) were measured, and the potentially toxic elements (PTEs, i.e. Zn, Cu, Pb, Ni and Cd) were analyzed for the total content, speciation, and leaching potential. Compared with pyrochars derived from the same feedstock, hydrochars had lower pH and higher cation exchange capacity. The available content of N (1.58-6.87 g/kg), P (0.270-0.901 g/kg), and K (0-0.873 g/kg) in the chars was less than the feedstock sludge (3.33 g/kg N, 3.02 g/kg P, 2.07 g/kg K), but still far higher than that of the agricultural soil (i.e. 0.014-0.488 g/kg N, 0.02 g/kg P, <0.1-0.272 g/kg). Remarkably, hydrochars showed better nutritional balance than pyrochars for its higher available K content. Risk of potentially toxic elements contamination by the sludge was efficiently reduced in either hydrochars or pyrochars, except the high leaching potential of Zn in pyrochars. Overall, in addition to the advantages of the hydrothermal carbonization process as energy saving and value-added liquid by-products, the hydrochars derived from sludge, with sufficient and balanced nutrients and limited PTEs pollution risk, can be a feasible and value-added material as soil amendment.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31550122

RESUMO

Based on arrays of Au seeds fabricated with atomic force microscopy (AFM) nanoxerography, the seeded growth of gold nanoparticles (Au NPs) on surface is achieved. The size evolution of Au NPs in each spot is tracked by in situ AFM and SEM images because each spot can be easily localized in the array system. The extinction microspectra extracted in real time with enhanced signals and red-shift can further monitor the increasing size of Au NPs. As a powerful platform, AFM nanoxerography makes it easy to tune the spot size and the intervals among spots in the Au NP arrays without preparing a template. It also allows for fabricating arbitrary patterns including various symbols and graphs. More interestingly, the in situ growth of Au NPs offers an approach to decreasing the interparticle distance, and thus forming closely interconnected Au nanowire assembly, exhibiting immense potential in the nanoelectronic system.

4.
J Invest Surg ; : 1-10, 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31438740

RESUMO

Polyethylene glycol (PEG) has previously been reported to improve outcomes of peripheral nerve microsuturing. However, recent studies have challenged this finding. Given its clinical importance, we investigated the potential of PEG as a facilitator of peripheral nerve restoration. The sciatic nerve of 144 rats was transected and submitted either to simple suturing (Group A), PEG-enhanced suturing (Group B), and insertion in an arterial sleeve conduit without PEG (Group C), or with PEG (Group D) in equal numbers. Behavioral recovery was assessed with the sciatic function index (SFI). Nerve impulse conduction was assessed with compound muscle action potentials (CMAPs). Histology comprised standard hematoxylin/eosin staining, electron microscopy and glial cell line-derived neurotrophic factor (GDNF) immunohistochemistry. Expression of GDNF was also assessed with western blotting. Results were evaluated at weeks 1, 4, and 8. PEG treatment significantly improved behavioral recovery and morphology of nerve restoration, particularly in the sleeve conduit group, relative to that of controls. In conclusion, PEG may improve outcomes of peripheral nerve reconstruction.

5.
Med Sci Monit ; 25: 4583-4589, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31257361

RESUMO

BACKGROUND The apoptosis of corneal epithelial cells participates in the pathological processes of dry eye, which is expected to be a treatment target for dry eye. The aim of this study was to investigate the effects of vitamin A (VA) on apoptosis of corneal epithelial cells in a mouse model with dry eye induced by benzalkonium chloride (BAC). MATERIAL AND METHODS We randomly divided 60 male BALB/c mice aged 8-10 weeks into 3 groups: the blank control group, the dry eye + vehicle group, and the dry eye + drug group. On the 7th day after the dry eye model successfully induced, the mouse eyeballs removed, and the mouse corneal tissues were isolated. The expression levels of Bax and Bcl-2 in corneal tissues were detected via reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting. The apoptotic corneal epithelial cells were quantified using terminal deoxynucleotidyl transferase (TdT) deoxyuridine triphosphate (dUTP) nick-end labeling (TUNEL) staining technique. RESULTS VA suppressed the upregulation of the Bax gene at the mRNA and protein levels, and upregulated the expression of the Bcl-2 gene (P<0.05). TUNEL results revealed that the number of apoptotic epithelial cells in the dry eye group was 40 times larger as that in the blank control group. After the intervention of VA at an appropriate concentration, the number of apoptotic corneal epithelial cells was remarkably reduced to about 10 times that in the blank control group (P<0.05). CONCLUSIONS VA can inhibit upregulation of the expressions of Bax and Bcl-2 in the epithelial cells of mice with dry eye induced by BAC, so as to suppress the apoptosis of epithelial cells in mice with dry eye.

6.
Int J Mol Med ; 44(3): 1117-1126, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31257458

RESUMO

Endoplasmic reticulum (ER) stress can be activated by ischemia/reperfusion (I/R) injury in cardiomyocytes. Persistent ER stress, with an increase in intracellular Ca2+ ([Ca2+]i) concentration, leads to apoptosis. Protein kinase C (PKC) has a key role in myocardial damage by elevation of [Ca2+]i. The calcium­sensing receptor (CaSR), a G protein­coupled receptor, can increase the release of [Ca2+]i from the ER through the inositol triphosphate receptor (IP3R). Intracellular calcium overload has been demonstrated to cause cardiac myocyte apoptosis during I/R. However, the associations between PKC, CaSR and ER stress are not clear. The present study examined the hypothesis that activation of PKCδ by CaSR participates in ER stress­associated apoptotic pathways within myocardial I/R. Rat hearts were subjected to 30 min of ischemia in vivo, followed by reperfusion for 120 min. GdCl3 (a CaSR activator) was used to elevate the intracellular Ca2+ concentration, but the Ca2+ concentration in the ER was significantly decreased during I/R. Following exposure to GdCl3, expression levels of CaSR, glucose­regulated protein 78 (GRP78), Caspase­12, phosphorylated JNK and Caspase­3 were increased, and the ratios of apoptotic myocardial cells were significantly increased. By contrast, following exposure to rottlerin, a PKCδ inhibitor, the expression levels of these proteins and the ratio of apoptotic myocardial cells were significantly reduced. The present study also demonstrated that PKCδ translocated into the ER to induce an ER stress response and participate in the ER stress­related apoptosis pathway. These results confirmed that CaSR activated PKCδ to induce cardiomyocyte apoptosis through ER stress­associated apoptotic pathways during I/R in vivo.

7.
Health Phys ; 117(3): 291-299, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31349355

RESUMO

This paper presents the count rate enhancement observed across Canada's Fixed Point Surveillance network during the solar event on 20 January 2005 and explores the feasibility and value of applying the Fixed Point Surveillance network's long-term and continuous observations for space weather monitoring. The count rate, recorded in the high-energy channel of RS250 sodium iodide detectors, reflects the detector's response to muonic and electromagnetic components of the cosmic ray shower. During the event peak time, simultaneous count rate increases have been observed across many Fixed Point Surveillance network stations at enhancements varying from 10% to 18%, 12- to 15-fold less than relative increases in neutron detector observations.

8.
Environ Sci Pollut Res Int ; 26(26): 26517-26528, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31292866

RESUMO

Lotus seed shell was employed using one-step method combining carbonization with ZnCl2 activation to synthesize activated carbons because of its inexpensiveness and local accessibility. The lotus seed shell-activated carbons (LSSACs) with the highest surface area (2450.8 m2/g) and mesoporosity (98.6%) and the largest pore volume (1.514 cm3/g) were tailored under optimum conditions as follows: impregnation ratio = 2:1, carbonization temperature = 600 °C, and time = 1.0 h. The surface Zn(II), abundant hydroxyl, and carboxyl functional groups from the activation process could result in rapid Pb(II) adsorption onto the LSSAC surface through surface complexation, ion exchange, or precipitation. The maximum monolayer adsorption capacity (qm) for Pb(II) of 247.7 mg/g at 25 °C could be fitted from the Langmuir isotherm. The Gibbs free energy (△G) and positive enthalpy (△H) indicated that the adsorption process was spontaneous and endothermic, and to some extent, it was explained by the intra-particle diffusion mechanism. Our results may provide a promising way to produce activated carbons with high adsorption capacity using solid waste, which will eventually promote the environmental sustainability.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31251366

RESUMO

A tissue-equivalent proportional counter (TEPC) is a reference detector to measure microdosimetric quantities. A conventional spherical TEPC and a novel TEPC based on a ceramic thick gas electron multiplier (THGEM) foil were developed to carry out microdosimetric measurements of lineal energy spectra in monoenergetic and 252Cf/241Am-Be neutron radiation fields, and the absorbed dose values had been derived. In order to go further in radiobiology and therapy, the fluence to absorbed dose conversion coefficients in neutron fields were also determined. According to the dose distribution in lineal energy, the neutron relative biological effect (RBE) values were also calculated using an empirical procedure applying biological weighting functions.

10.
Org Lett ; 21(13): 5096-5100, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31194561

RESUMO

A novel metal-free tandem Csp3-H bond functionalization of ketones and 1,3-dipolar cycloaddition has been developed. An efficient approach to a variety of oxazole and isoxazoline derivatives is demonstrated using the 1,3-dipolar cycloaddition of alkynes and alkenes to nitrile oxides generated by reactions of methyl ketones with tert-butyl nitrite. This new protocol provides access to a variety of isoxazolines with diverse functionalities. An isoxazole generated in this way was found to have significant antifungal activity.

11.
Anal Chem ; 91(15): 10295-10301, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31246423

RESUMO

The discrimination of glycosaminoglycans (GAGs) is a challenging task but of great importance to ensure their safe use in clinics. Herein, four supramolecular AIE nanoassemblies denoted as PDDA-TPE100, PDDA-TPE75, PDDA-TPE50, and PDDA-TPE25 were synthesized by loading different amounts of the negatively charged AIEgen TPE onto the surface of the positively charged polymer PDDA. These AIE nanoassemblies were utilized for the construction of a fluorescent sensor array, which was able to discriminate various GAGs on the basis of a compaction to displacement reaction mechanism. LDA and HCA results revealed that GAGs including Hep, Chs, HA, CTS, DS, and OSCS can be discriminated with 100% accuracy. The four-sensor array was then simplified to a three-sensor array using PDDA-TPE100, PDDA-TPE75, and PDDA-TPE50 as the sensors, which was determined to be still powerful in discrimination of various GAGs, accurate identification of unknown GAG samples, sensitive detection of trace OSCS contaminant in Hep, and identification of Hep and other biologically abundant anions. Moreover, the three-sensor array was even successfully applied for differentiating GAGs in serum media.

12.
Nanoscale ; 11(26): 12471-12476, 2019 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-31219124

RESUMO

Smartphone-compatible biosensors are believed to be one of the key techniques for improving the quality of diagnosis in remote areas. However, to date, few smartphone-compatible biosensors can reach the specifications of their conventional counterparts due to the limitations of consumer-grade detectors carried by phones. To circumvent this issue, we reported a metasurface-inspired bio-sensor, patterned plasmonic gradient (PPG), which transduces local index information into 2D patterns. By harnessing the powerful imaging and computational capability of modern smartphones, the PPG is sensitive enough to detect tiny refractive index changes induced by a submonolayer of molecules with high precision (Δn < 0.001) in a large dynamic range. It allows us to monitor the conjugation process between biotin and a trace amount of streptavidin (15 nM, 20 µL) in real-time. With high sensitivity and accuracy, the PPG provides a high performance bio-sensing solution for the places where professional equipment is inaccessible.

13.
Dalton Trans ; 48(25): 9181-9186, 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-31149684

RESUMO

The reaction mechanism of the Ru(ii)-catalyzed regioselective C-H allylation of indoles with allyl alcohols has been studied by density functional theory (DFT) calculations. This reaction mechanism involves five major steps: deprotonation of amide-NH, arene C-H activation, allyl alcohol insertion, ß-OH elimination and protonation. Our calculation results indicate that C2-H bond allylation is better than C7-H bond allylation, which can be attributed to the stronger nucleophilicity of C2 compared to C7 in the C-Ru bond insertion of indole substrates. Furthermore, we also suggest that C-Ru bond insertion is more favorable than N-Ru bond insertion, which can be attributed to the different hybridization states of the relevant carbon and nitrogen atoms. Meanwhile, we also illustrate that the substrate cinnamyl alcohol cannot give the desired product due to the steric hindrance of the phenyl ring in cinnamyl alcohol with the indole skeleton.

14.
Am J Physiol Endocrinol Metab ; 317(2): E284-E297, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31184932

RESUMO

Hydrogen sulfide (H2S), a gaseous molecule, is involved in modulating multiple physiological functions, such as antioxidant, antihypertension, and the production of polysulfide cysteine. H2S may inhibit reactive oxygen species generation and ATP production through modulating respiratory chain enzyme activities; however, the mechanism of this effect remains unclear. In this study, db/db mice, neonatal rat cardiomyocytes, and H9c2 cells treated with high glucose, oleate, and palmitate were used as animal and cellular models of type 2 diabetes. The mitochondrial respiratory rate, respiratory chain complex activities, and ATP production were decreased in db/db mice compared with those in db/db mice treated with exogenous H2S. Liquid chromatography with tandem mass spectrometry analysis showed that the acetylation level of proteins involved in the mitochondrial respiratory chain were increased in the db/db mice hearts compared with those with sodium hydrosulfide (NaHS) treatment. Exogenous H2S restored the ratio of NAD+/NADH, enhanced the expression and activity of sirtuin 3 (SIRT3) and decreased mitochondrial acetylation level in cardiomyocytes under hyperglycemia and hyperlipidemia. As a result of SIRT3 activation, acetylation of the respiratory complexe enzymes NADH dehydrogenase 1 (ND1), ubiquinol cytochrome c reductase core protein 1, and ATP synthase mitochondrial F1 complex assembly factor 1 was reduced, which enhanced the activities of the mitochondrial respiratory chain activity and ATP production. We conclude that exogenous H2S plays a critical role in improving cardiac mitochondrial function in diabetes by upregulating SIRT3.

15.
Opt Express ; 27(7): 10370-10382, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31045180

RESUMO

Fast detection and identification of chemicals are of utmost importance for field testing and real-time monitoring in many fields. Raman spectroscopy is the predominant technique in principle, but its wide application is limited on account of weak scattering efficiency. Surface Enhanced Raman Spectroscopy (SERS) technique provides a solution for signal enhancement, but may not good at fast detection due to cross contamination and bulky instruments. Hollow-core fiber-based Raman cell with long interaction length can achieve high detection sensitivity, but it also suffers from low flow rate, bulky high-pressure equipment and light coupling structure, which also restricts its application for fast detection. In order to solve those problems, we proposed a portable Raman cell, by using metal-lined hollow-core fibers (MLHCF) with large bandwidth, good field confinement, extremely large numerical aperture and arbitrary length. With our proposed fiber inserted light coupling and light reflecting method, a Raman cell of 3.1 cm in length provides nearly 50 times of signal enhancement compared with direct detection using bare fiber tip. Furthermore, the sample exchange rate could be as fast as 1 second even under normal pressure without any cross contamination. At last, we also demonstrated the underlying general mechanism of signal enhancement and summarized it as volumetric enhancement of Raman scattering (VERS). Both the experiment results and the theoretical analysis demonstrated that our device has the potential for fast online Raman detection, which also possesses high-sensitivity and high-accuracy.

16.
Diabetes ; 68(8): 1681-1691, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31088856

RESUMO

Liver dysfunction and type 2 diabetes (T2D) are consistently associated. However, it is currently unknown whether liver dysfunction contributes to, results from, or is merely correlated with T2D due to confounding. We used Mendelian randomization to investigate the presence and direction of any causal relation between liver function and T2D risk including up to 64,094 T2D case and 607,012 control subjects. Several biomarkers were used as proxies of liver function (i.e., alanine aminotransferase [ALT], aspartate aminotransferase [AST], alkaline phosphatase [ALP], and γ-glutamyl transferase [GGT]). Genetic variants strongly associated with each liver function marker were used to investigate the effect of liver function on T2D risk. In addition, genetic variants strongly associated with T2D risk and with fasting insulin were used to investigate the effect of predisposition to T2D and insulin resistance, respectively, on liver function. Genetically predicted higher circulating ALT and AST were related to increased risk of T2D. There was a modest negative association of genetically predicted ALP with T2D risk and no evidence of association between GGT and T2D risk. Genetic predisposition to higher fasting insulin, but not to T2D, was related to increased circulating ALT. Since circulating ALT and AST are markers of nonalcoholic fatty liver disease (NAFLD), these findings provide some support for insulin resistance resulting in NAFLD, which in turn increases T2D risk.

17.
J Int Med Res ; 47(6): 2716-2722, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31032675

RESUMO

Solitary fibrous tumours are unusual neoplasms that develop from mesenchymal cells, usually originating from the pleura. A pericardial solitary fibrous tumour is an extremely rare occurrence. We report a 64-year-old woman who presented to the hospital with chief complaints of dyspnoea and abdominal distension. Echocardiography and enhanced computed tomography revealed an intrapericardial tumour with local invasion to the right atrium. Histopathological examination of a biopsy specimen showed a patternless distribution of spindle-shaped cells in a collagen stroma, with a high mitosis rate. Immunohistochemistry was positive for vimentin, CD34, and Bcl-2. The final diagnosis was a pericardial malignant solitary fibrous tumour with right atrial invasion. Surgical resection of the tumour was not performed because of its invasion into the myocardium. We systematically reviewed the literature on cardiac solitary fibrous tumours up to 2019.

18.
Sci China Life Sci ; 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-31016536

RESUMO

The lifestyle transition of fungi, defined as switching from taking organic material as nutrients to pathogens, is a fundamental phenomenon in nature. However, the mechanisms of such transition remain largely unknown. Here we show microRNA-like RNAs (milRNAs) play a key role in fungal lifestyle transition for the first time. We identified milRNAs by small RNA sequencing in Arthrobotrys oligospora, a known nematode-trapping fungus. Among them, 7 highly expressed milRNAs were confirmed by northern-blot analysis. Knocking out two milRNAs significantly decreased A. oligospora's ability to switch lifestyles. We further identified that two of these milRNAs were associated with argonaute protein QDE-2 by RNA-immunoprecipitation (RIP) analysis. Three of the predicted target genes of milRNAs were found in immunoprecipitation (IP) products of QDE-2. Disruption of argonaute gene qde-2 also led to serious defects in lifestyle transition. Interestingly, knocking out individual milRNAs or qde-2 lead to diverse responses under different conditions, and qde-2 itself may be targeted by the milRNAs. Collectively, it indicates the lifestyle transition of fungi is mediated by milRNAs through RNA interference (RNAi) machinery, revealing the wide existence of miRNAs in fungi kingdom and providing new insights into understanding the adaptation of fungi from scavengers to predators and the mechanisms underlying fungal infections.

19.
Sci Total Environ ; 673: 245-253, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-30991316

RESUMO

A two-year soil incubation experiment was performed to investigate the long-term impacts of biochars (kenaf core and sewage sludge biochar (KBC and SBC) pyrolyzed at 350 °C and 550 °C) on metal(loid)s immobilization. Both KBC and SBC can immobilize Pb and Cu in contaminated soil, whereas they showed little effects on the immobilization of Zn, Cd and As. Interactions between the biochar and soil during two-year aging changed the metal species on both soil and biochar particles. KB350 formed more biochar-mineral complexes and O-containing functional groups than KB550 and thus transferred more residual metal(loid)s to their reducible species. More metal(loid)s sorbed on the KB350 than KB550 after two-year aging. However, SBC changed the acid-soluble species of metal(loid)s into the residual species during the aging process, probably due to the release of phosphate. Upon aging, SB550 exhibited a more significant increase in the residual metal amount and more sorption of metal(loid)s on the biochar particles than SB350 due to sorption of organic carbon and formation of meta-kaolinite. A key finding of our study was that different biochars have contrasting impacts on metal speciation and lability upon 2-year aging. This should be considered in assessing the actual risk of biochar-amended soils.


Assuntos
Carvão Vegetal/química , Recuperação e Remediação Ambiental/métodos , Metais/análise , Poluentes do Solo/análise , Poluição Ambiental , Solo
20.
Anal Chem ; 91(9): 5817-5823, 2019 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-30935199

RESUMO

The detection of moisture in organic solvents is very important before their use in water-sensitive reactions. Herein, we report that coumarins D1 and D2 were able to generate the corresponding water-sensitive copper complexes D1-Cu and D2-Cu in common organic solvents, which can be used as efficient fluorescent turn-on sensors for water. Single-crystal diffraction analysis of the reaction product indicated that the sensing mechanism is based on the formation of a water-bridged 3D supramolecular hydrogen-bonding network. We demonstrated that a hydroxyl or amine group substituted at the 7-position of the coumarin framework played a key role in the water-sensing performance of D1-Cu and D2-Cu, by acting as a hydrogen bond acceptor in the supramolecular network. This provided a general strategy for designing such coumarin-based copper complexes for fluorescent water sensing. The water-sensing behavior of D1-Cu and D2-Cu were determined to be fast, pH tolerant, and sensitive. As low as 0.0525 wt % of water in methanol can be detected using D1-Cu as the sensor. Moreover, D1-Cu was successfully used for moisture sensing in real commercial products.

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