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1.
Anal Chim Acta ; 1093: 150-159, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31735208

RESUMO

As a powerful tool for medical diagnosis and bioanalysis, conventional optical spectrometers are generally expensive, bulky and always require an accompanying data processing device. In this work, we developed a novel smartphone-based CD-spectrometer (SCDS) for high sensitive and ultra-portable colorimetric analysis, with the advantage of cost-effective and simplicity. The distance between the light source and slit, the structure of SCDS and the parameters of camera in the smartphone were all optimized to ensure the best analytical performance. Besides, the SCDS employed HSV color model and utilized the overall intensity calculated by summing V-value of adjacent position for the absorbance measurement. In this way the errors caused by the low resolution of CD-grating can effectively be eliminated to promote the sensitivity of the SCDS. The performance of the SCDS was first validated for colorimetric detection of BSA with a detection limit of 0.0073 mg/mL, which is superior compared to that of the microtiter plate reader (MTPR). Moreover, by combining with 3,3',5,5'-tetramethylbenzidine-manganese dioxide (TMB-MnO2) nanosheets reaction, a high sensitive and specific system for ascorbic acid detection was established. The SCDS gives a detection range from 0.6250 µM to 40 µM with a detection limit of 0.4946 µM for AA detection. Compared to other studies, the SCDS features wide detection range and very low detection limit with low cost instrument. Therefore, the SCDS will be an ideal and promising colorimetric system for point-of-care (POC) application in food security, disease diagnosis and environmental monitoring.

2.
Carbohydr Polym ; 228: 115389, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31635730

RESUMO

The modified rice starches by octenyl succinic anhydride (OS-RSs) with the same degree of substitution of 0.033 were prepared in aqueous solution using 3% or 20% (w/w) NaOH as a catalyst (OS-RS 3 or OS-RS 20). The results indicated that 20% of NaOH could destroy the structure of starch more seriously and led to more OS groups travelling to interior of starch granules. Furthermore, the storage stability and rheological properties of Pickering emulsions formulated by RS, OS-RS 3 and OS-RS 20 were investigated. Emulsion index of OS-RS 20 were always lower than OS-RS 3 during the storage time, while G', G" and viscosity of O/W Pickering emulsion formulated by OS-RS 20 particles were greater than those of OS-RS 3. OS-RS 3 with more hydrophobic groups in the granule surface could form more compact oil/water layers which contributed greater to the storage stability of Pickering emulsion due to the formation of more compact oil/water layers. However, OS-RS 20 with homogeneous distribution of OS groups in the whole particles resulted in the formation of a tighter droplet network structure that was more resistant to external impacts, which showed OS-RS 20 could improve the shear stability of Pickering emulsion.

3.
Sci Rep ; 9(1): 18057, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31792242

RESUMO

Arbuscular mycorrhizal (AM) fungi play an important role in plant-fungi communities. It remains a central question of how the AM fungal community changes as plants grow. To establish an understanding of AM fungal community dynamics associated with Chinese fir, Chinese fir with five different growth stages were studied and 60 root samples were collected at the Jiangle National Forestry Farm, Fujian Province. A total of 76 AM fungal operational taxonomic units (OTUs) were identified by high-throughput sequencing on an Illumina Miseq platform. The genera covered by OTUs were Glomus, Archaeospora, Acaulospora, Gigaspora and Diversispora. Glomus dominated the community in the whole stage. The number and composition of OTUs varied along with the host plant growth. The number of OTUs showed an inverted V-shaped change with the host plant age, and the maximum occurred in 23-year. Overall, the basic species diversity and richness in this study were stable. Non-metric multi-dimensional scaling (NMDS) analysis based on bray-curtis distance revealed that there were remarkable differentiations between the 9-year and other stages. Besides, AM fungal community in 32-year had a significant difference with that of 23-year, while no significant difference with that of 45-year, suggesting that 32-year may be a steady stage for AM fungi associated with Chinese fir. The cutting age in 32-year may be the most favorable for microbial community. The pH, total N, total P, total K, available N, available P, available K, organic matter and Mg varied as the Chinese fir grows. According to Mantel test and redundancy analysis, available N, available P, K and Mg could exert significant influence on AM fungal communities, and these variables explained 31% of variance in the composition of AM fungal communities.

4.
J Org Chem ; 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31793779

RESUMO

Here, we describe a convergent synthesis of human granulocyte-macrophage colony-stimulating factor (hGM-CSF) harboring both O- and N-glycosylation sites using a Se-auxiliary-mediated ligation protocol together with native chemical ligation methodology. The robust and rapid Se-mediated ligation enables assembly of the N-terminus of hGM-CSF in just 4 h, which is significantly faster than the traditional ligation/desulfurization method. Therefore, this new methodology could help to produce hGM-CSF glycoform libraries more efficiently for future elucidation of the importance of glycosylation.

5.
Alzheimers Dement ; 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31784375

RESUMO

INTRODUCTION: The Advancing Research and Treatment in Frontotemporal Lobar Degeneration and Longitudinal Evaluation of Familial Frontotemporal Dementia Subjects longitudinal studies were designed to describe the natural history of familial-frontotemporal lobar degeneration due to autosomal dominant mutations. METHODS: We examined cognitive performance, behavioral ratings, and brain volumes from the first time point in 320 MAPT, GRN, and C9orf72 family members, including 102 non-mutation carriers, 103 asymptomatic carriers, 43 mildly/questionably symptomatic carriers, and 72 carriers with dementia. RESULTS: Asymptomatic carriers showed similar scores on all clinical measures compared with noncarriers but reduced frontal and temporal volumes. Those with mild/questionable impairment showed decreased verbal recall, fluency, and Trail Making Test performance and impaired mood and self-monitoring. Dementia was associated with impairment in all measures. All MAPT carriers with dementia showed temporal atrophy, but otherwise, there was no single cognitive test or brain region that was abnormal in all subjects. DISCUSSION: Imaging changes appear to precede clinical changes in familial-frontotemporal lobar degeneration, but specific early clinical and imaging changes vary across individuals.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31790575

RESUMO

Red phosphorus (RP) as the anode material for sodium-ion battery (SIB) owns a high energy density, but the poor electronic conductivity and huge volume change during Na+ insertion/extraction restrict its application. In this work, the edible fungus slag-derived porous carbon (PC) is adopted as a carbon matrix to combine with RP to form PC@RP composites through a facile vaporization-condensation approach. The nano-sized RP particles are uniformly distributed in the PC matrix. The conductive porous carbon architecture improves the transfer of electron and Na+ in the composite. The robust carbon framework together with the chemical bonding between PC and RP effectively buffer the huge volumetric change of RP. As a result, the PC@RP composite material delivers a specific capacity of 670 mA h g-1 at 0.1 A g-1 with a capacity retention of 87% after 100 charging/discharging cycles. In particular, the full SIB assembled with P2-Na2/3Ni1/3Mn1/3Ti1/3O2 as the cathode material and PC@RP as the anode material exhibits a specific capacity of 77.3 mA h g-1 (based on the mass of the composite cathode material) at 0.5 C, and 85% capacity is retained after 100 charging/discharging cycles.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31786739

RESUMO

PROPOSE: Poly (ADP-ribose) polymerase 1 inhibitors were originally investigated as anti-cancer therapeutics with BRCA1/2 genes mutation. Here, we investigate the effectiveness of a novel PARP1 inhibitor fluzoparib, for enhancing the radiation sensitivity of NSCLC cells lacking BRCA1/2 mutation. METHODS: We used MTS assays, western blotting, colony formation assays, immunofluorescence staining, and flow cytometry to evaluate the radiosensitization of NSCLC cells to fluzoparib and explore the underlying mechanisms in vitro. Through BRCA1 and RAD50 genes knockdown, we established dysfunctional homologous recombination (HR) DNA repair pathway models in NSCLC cells. We next investigated the radiosensitization effect of fluzoparib in vivo using human NSCLC xenograft models in mice. The expression of PARP1 and BRCA1 in human NSCLC tumor samples was measured by immunohistochemistry. Furthermore, we sequenced HR-related gene mutations and analyzed their frequencies in advanced NSCLC. RESULTS: In vitro experiments in NSCLC cell lines along with in vivo experiments using an NSCLC xenograft mouse model demonstrated the radiosensitization effect of fluzoparib. The underlying mechanisms involved increased apoptosis, cell-cycle arrest, enhanced irradiation-induced DNA damage, and delayed DNA-damage repair. Immunohistochemical staining showed no correlation between the expression of PARP1 and BRCA1. Moreover, our sequencing results revealed high mutation frequencies for the BRCA1/2, CHEK2, ATR, and RAD50 genes. CONCLUSION: The potential therapeutic value of fluzoparib for increasing the radiation sensitivity of NSCLC is well confirmed. Moreover, our findings of high mutation frequencies among HR genes suggest that PARP1 inhibition may be an effective treatment strategy for advanced non-small cell lung cancer patients.

8.
BMC Public Health ; 19(1): 1599, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31783746

RESUMO

BACKGROUND: Higher dietary acid load (DAL) was considered to be associated with an elevated risk of hypertension, while related data from mainland China remains scarce and incomplete. We aim to evaluate the association between DAL and the risk of hypertension among adults from South China. METHODS: We conducted a nutrition and health survey in Guangdong Province located in southern China from 2015 to 2017. A four-stage probability sampling method was utilized to select representative samples of citizens aged ≥18 years old. DAL was assessed by potential renal acid load (PRAL) and net endogenous acid production (NEAP). Participants were divided to 4 groups (Q1-Q4) according to the quartile points of PRAL or NEAP distributions. Generalized linear mixed effects models were applied to evaluate the association between DAL and the risk of hypertension. RESULTS: A total of 3501 individuals were eligible for this study and 45.9% was male participants. Hypertension rate was 30.7%. A higher PRAL was associated with higher prevalence rate of hypertension among the male (P-trend = 0.03). OR for Q2 was 1.34 (95%CI, 0.94-1.91), Q3 was 1.53 (95%CI = 1.08, 2.16) and Q4 was 1.51 (95%CI, 1.08-2.16) among the male. However, as for total participants, the female, the participants with ≤55 years or participants with > 55 years, the associations were lack of significance. With respect to association between NEAP and hypertension, non-significant results were identified. CONCLUSIONS: The current study indicated male hypertension was associated with higher PRAL, while given to this study was cross-sectional design, further studies are warranted to verify the association.

9.
J Clin Pathol ; 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31796635

RESUMO

AIM: Tissue microarray (TMA) is a powerful and effective tool for in situ tissue analysis. However, manual TMA construction methods showed varied qualities. This study aimed to raise a standardised TMA preparation technique that can be easily operated and is economical. METHODS: A sampling needle was used to punch the tissue rods from the donor block and holes in the recipient block. To indicate the dots' positions and ensure vertical punching, a novel auxiliary device made using commercial three-dimensional printing technology was attached. The TMA block was made up of tissue rods and a recipient block. RESULTS: A 77-rod (7×11) TMA block was constructed. The rows and columns were fixed in straight lines. There was no specimen loss during the process of embedding. CONCLUSIONS: An alternative method for the construction of TMA blocks that met the basic requirement of many laboratories and can be effortlessly performed was presented.

10.
Sci Rep ; 9(1): 18248, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31796756

RESUMO

Vascular dementia (VaD) is a complex disorder caused by reduced blood flow in the brain. However, there is no effective pharmacological treatment option available until now. Here, we reported that low-dose levamlodipine besylate could reverse the cognitive impairment in VaD mice model of right unilateral common carotid arteries occlusion (rUCCAO). Oral administration of levamlodipine besylate (0.1 mg/kg) could reduce the latency to find the hidden platform in the MWM test as compared to the vehicle group. Furthermore, vehicle-treated mice revealed reduced phospho-CaMKII (Thr286) levels in the hippocampus, which can be partially restored by levamlodipine besylate (0.1 mg/kg and 0.5 mg/kg) treatment. No significant outcome on microglia and astrocytes were observed following levamlodipine besylate treatment. This data reveal novel findings of the therapeutic potential of low-dose levamlodipine besylate that could considerably enhance the cognitive function in VaD mice.

12.
Medicine (Baltimore) ; 98(49): e18038, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31804310

RESUMO

In the absence of liver biopsy and transient elastography (TE), aspartate aminotransferase to platelet ratio (APRI), fibrosis-4 score (FIB-4), and gammaglutamyl transpeptidase to platelet ratio (GPR) are simple and inexpensive methods for the detection of liver fibrosis. AIMS: We compared the performance of APRI, FIB-4, and GPR scores against TE in predicting the presence of liver fibrosis and cirrhosis, determined the optimal cut-off values for fibrosis and cirrhosis prediction, and reviewed the need for further TE assessment in resource-limited areas in China. METHODS: TE and basic laboratory tests were performed in 2014 consecutive patients with chronic hepatitis B (CHB), and then compared to APRI, FIB-4, and GPR. RESULTS: For the detection of significant fibrosis, the areas under the receiver operating characteristic (AUROC) curves for APRI, FIB-4, and GPR were 0.83, 0.75, and 0.77, respectively. For the detection of cirrhosis, the AUROC curves for APRI, FIB-4, and GPR were 0.90, 0.84, and 0.84, respectively. The cutoff of APRI was 0.35, with 78% sensitivity and 63% negative predictive value (NPV), to exclude significant fibrosis (F ≥ 2). At an APRI of 0.6, results showed a 94% specificity, 100% positive predictive value (PPV) and 7.9 positive likelihood ratio (PLR) in detecting significant fibrosis. Thus, patients with an APRI of <0.35 or >0.6 demonstrated correct prediction of liver fibrosis. These results translated to 1250 out of the 2014 patients avoiding the need for TE with a diagnostic accuracy of >80%. CONCLUSIONS: The APRI score accurately assessed fibrosis and reduced the need for TE in almost two-thirds of Chinese patients with CHB.

13.
Toxicol Sci ; 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31804693

RESUMO

Although studies have shown toxic effects of zinc oxide (ZnO) particles following inhalation, additional effects on injured lungs, which are characterized by dysfunction of the alveolar-capillary barriers, remain uncharacterized. To explore these additional effects, nano-sized ZnO (nZnO) and bulk-sized ZnO (bZnO) were applied to lipopolysaccharide (LPS)-challenged mouse lungs, which were used as a disease model of acute lung inflammation. An elevated Zn2+ concentration was detected in lung tissue after LPS plus nZnO exposure. Exposure to nZnO in LPS-challenged mice resulted in higher total cell number, proportion of neutrophils, and total protein level in bronchoalveolar lavage fluid. Intratracheal instillation of nZnO intensively aggravated LPS-induced lung inflammation that was accompanied by enhanced expression of interleukin-1ß, interleukin-6, monocyte chemotactic protein-1αand granulocyte-macrophage colony stimulating factor. Catalase, glutathione, and total superoxide dismutase levels were significantly decreased, and the malondialdehyde level was obviously increased in the LPS plus nZnO group. 8-Hydroxyguanosine, a marker for DNA damage, was highly concentrated in the lungs from the LPS plus nZnO group. Furthermore, nZnO increased lung apoptosis in an acute lung inflammation model. Taken together, this evidence indicates that nZnO aggravates lung inflammation related to LPS. This enhancement effect may be mediated via oxidative stress, which can lead to DNA damage and apoptosis. This work is important because of the ever-increasing exposure of people to ZnO nanoparticles in industry. The identification of the toxic effects of nZnO and possible mechanisms revealed in this study provide valuable information for future studies.

14.
Chemistry ; 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31804733

RESUMO

Electro-induced reduction of redox active esters and Nphthalimidoyl oxalates derived from naturally abundant carboxylic acids and alcohols provides a sustainable and inexpensive approach to radical formation via undivided electrochemical cells. The resulting radicals are trapped by an electron-poor olefin or hydrogen atom source to furnish the Giese reaction or reductive decarboxylation products, respectively. A broad range of carboxylic acid (1°, 2°, and 3°) and alcohol (2° and 3°) derivatives are applicable in this catalystfree reaction, which tolerated a diverse range of functional groups. This method features simple operation, sustainable platform and broad applications.

15.
J Clin Invest ; 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31689244

RESUMO

Hereditary hemorrhagic telangiectasia (HHT), a genetic bleeding disorder leading to systemic arteriovenous malformations (AVMs), is caused by loss-of-function mutations in the ALK1-ENG-Smad1/5/8 pathway. Evidence suggests that HHT pathogenesis strongly relies on overactivated PI3K-Akt-mTOR and VEGFR2 pathways in endothelial cells (ECs). In the BMP9/10-immunoblocked (BMP9/10ib) neonatal mouse model of HHT, we report here that the mTOR inhibitor, sirolimus, and the receptor tyrosine-kinase inhibitor, nintedanib, could synergistically fully block, but also reversed, retinal AVMs to avert retinal bleeding and anemia. Sirolimus plus nintedanib prevented vascular pathology in the oral mucosa, lungs, and liver of the BMP9/10ib mice, as well as significantly reduced gastrointestinal bleeding and anemia in inducible ALK1-deficient adult mice. Mechanistically, in vivo in BMP9/10ib mouse ECs, sirolimus and nintedanib blocked the overactivation of mTOR and VEGFR2, respectively. Furthermore, we found that sirolimus activated ALK2-mediated Smad1/5/8 signaling in primary ECs-including in HHT patient blood outgrowth ECs-and partially rescued Smad1/5/8 activity in vivo in BMP9/10ib mouse ECs. These data demonstrate that the combined correction of endothelial Smad1/5/8, mTOR, and VEGFR2 pathways opposes HHT pathogenesis. Repurposing of sirolimus plus nintedanib might provide therapeutic benefit in HHT patients.

16.
Biosens Bioelectron ; 149: 111842, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31726273

RESUMO

Effective detection of cancer biomarkers plays a crucial role in the prevention of early cancer. Here, a sandwich-type electrochemical immunosensor was successfully constructed for sensitive detection of carcinoembryonic antigen (CEA) using MoS2/CuS-Au as sensing platform and mulberry-like Au@PtPd porous nanorods (Au@PtPd MPs) as signal amplifiers. The large surface area and good biocompatibility of MoS2/CuS-Au increased the loading of primary antibody. And the good conductivity of MoS2/CuS-Au accelerated the electron transport rate of the electrode surface. Au@PtPd MPs with large specific surface area and a large number of catalytically active sites showed excellent electrocatalytic performance for hydrogen peroxide reduction. The sandwich-type immunosensor prepared by the signal amplification strategy exhibited a wide linear detection range (50 fg/mL to 100 ng/mL) and a low detection limit of 16.7 fg/mL (S/N = 3), featuring good selectivity, stability and reproducibility. Moreover, the satisfactory results in analysis of human serum samples indicated that it possessed a potential application promising in early clinical diagnoses.

17.
Inorg Chem ; 58(22): 15118-15125, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31702139

RESUMO

Due to the high carcinogenicity and bioaccumulation effects of dichromate ions in the human body, sensitive and rapid detection of Cr2O72- ions is necessary. Herein, two lanthanide coordination polymers based on a linear dicarboxylic acid ligand, named {Ln(cpon)(Hcpon)(H2O)3}n [Ln = Tb, Tbcpon; Eu, Eucpon; H2 cpon = 5-(4-carboxy-phenoxy)-nicotinic acid], have been successfully synthesized. These two isostructural compounds contain one-dimensional zigzag chains that consist of uncoordinated carboxyl groups and pyridine groups in the framework, and the one-dimensional chains can further form a three-dimensional supramolecular stacking structure by intermolecular interaction. Both Tbcpon and Eucpon show good luminescence performance and high stability. Tbcpon exhibits a good ability to sense Cr2O72- ions in aqueous solution. Moreover, the composite film material composed of Tbcpon and poly(methyl methacrylate) (PMMA) exhibits superior luminescence properties compared to those of pure Tbcpon. The Tbcpon-PMMA film exhibits an excellent ability to recognize Cr2O72- ions with high selectivity and a low detection limit of 5.6 ppb, which is much lower than the maximum contamination standard of 100 ppb in drinking water specified by the U.S. Environmental Protection Agency. Furthermore, the Tbcpon-PMMA film shows good recyclability for more than five cycles and anti-interference ability. After the introduction of the slightly soluble polymer poly(vinyl alcohol) (PVA), the Tbcpon-PVA composite film can effectively detect Cr2O72- ions in as little as 1 min. These composite films could be potentially used as test strips for trace detection and rapid detection of Cr2O72- ions in aqueous solution.

18.
Environ Pollut ; : 113306, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31733955

RESUMO

BACKGROUND: Exposure to particulate matters (PM) is recognized as an important risk factor for cardiovascular disease. A change in cardiac autonomic function is one postulated mechanism leading to PM related cardiovascular events. This study therefore evaluated the associations of short-term exposure to PM and heart rate variability (HRV) parameters, which can reflect the cardiac autonomic function. METHODS: Four electronic databases were searched for controlled studies of rodents published prior to December 2018. A systematic review and meta-analysis was conducted. Effect sizes were calculated for five main HRV parameters, including standard deviation of normal-to-normal intervals (SDNN), square root of mean squared differences between successive normal-to-normal intervals (rMSSD), low frequency (LF), high frequency (HF), and the ratio of LF and HF (LF/HF). RESULTS: The review included 23 studies with 401 animals. Short-term exposure to PM by instillation yielded statistically significant effects on SDNN (Standardized Mean Difference [SMD] = -1.11, 95% Confidence Intervals [CI] = -2.22 to -0.01, P = 0.05), LF (SMD = -1.19, 95% CI = -1.99 to -0.40, P = 0.003) and LF/HF (SMD = -1.05, 95% CI = -2.03 to -0.07, P = 0.04). Short-term exposure to PM by inhalation only yielded statistically significant effect on LF/HF (SMD = -0.83, 95% CI = -1.39 to -0.27, P = 0.004). There was no evidence that animal model and exposure frequency influenced the relationship of PM and HRV. CONCLUSIONS: Short-term exposure to PM can decrease HRV of rodents, affecting cardiac autonomic function. Exposure methods can influence the relationships of PM and HRV parameters. Further studies should focus on the effects of long-term PM exposure, on human beings, and potential influential factors of PM-HRV associations.

19.
Zootaxa ; 4619(1): zootaxa.4619.1.10, 2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31716322

RESUMO

Pseudoechthistatus hei Xie W. Wang sp. nov. from Yunnan, China is described and illustrated.


Assuntos
Besouros , Animais , China
20.
Zootaxa ; 4615(3): zootaxa.4615.3.10, 2019 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-31716338

RESUMO

This paper describes two new species of the genus Diestramima from China, i.e. Diestramima arbora sp. nov. and Diestramima lamina sp. nov. The morphological photographs of the two species are provided. All specimens are preserved in the Museum of Hebei University.


Assuntos
Ortópteros , Distribuição Animal , Estruturas Animais , Animais , Tamanho Corporal , China , Tamanho do Órgão
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