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1.
Inflammation ; 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31912281

RESUMO

The original version of this article was published with incorrect Fig. 1B. The correct Fig. 1B is now presented in Fig. 1 shown at the next page.

2.
J Forensic Sci ; 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31923319

RESUMO

Methyl nitrite is suggested to cause methemoglobinemia by generating methemoglobin, which may be lethal when the methemoglobin concentration exceeds 70%. However, intoxication with methyl nitrite is seldom reported compared with that with other nitrites. Here, we present an industrial accident involving methyl nitrite inhalation during its synthesis process that resulted in three fatalities and one survivor. The autopsy revealed conspicuous blue-gray discoloration in various parts of the body, including the skin, airway mucosa, vessels, brain, heart, and among other areas. The toxicological tests on the deceased showed methemoglobin concentrations in the blood over the lethal level and increased nitrite ion levels in the blood, gastric contents, liver, and lung tissue compared with those in control samples. The cause of death was determined to be methemoglobinemia-induced hypoxia due to methyl nitrite inhalation. This report provides evidence that in methyl nitrite intoxication, exposure duration has a significant influence on the postmortem changes and likelihood of a fatal outcome may be related to the age of the victim. More attention is required regarding the industrial hazards of this substance.

4.
Int J Mol Sci ; 21(2)2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31936000

RESUMO

Fermentable sugars are important intermediate products in the conversion of lignocellulosic biomass to biofuels and other value-added bio-products. The main bottlenecks limiting the production of fermentable sugars from lignocellulosic biomass are the high cost and the low saccharification efficiency of degradation enzymes. Herein, we report the secretome of Trichoderma harzianum EM0925 under induction of lignocellulose. Numerously and quantitatively balanced cellulases and hemicellulases, especially high levels of glycosidases, could be secreted by T. harzianum EM0925. Compared with the commercial enzyme preparations, the T. harzianum EM0925 enzyme cocktail presented significantly higher lignocellulolytic enzyme activities and hydrolysis efficiency against lignocellulosic biomass. Moreover, 100% yields of glucose and xylose were obtained simultaneously from ultrafine grinding and alkali pretreated corn stover. These findings demonstrate a natural cellulases and hemicellulases mixture for complete conversion of biomass polysaccharide, suggesting T. harzianum EM0925 enzymes have great potential for industrial applications.

5.
Fitoterapia ; : 104481, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31954179

RESUMO

In this study, seven previously undescribed steroidal glycoalkaloids, compounds 1-7, were isolated from Solanum lyratum, along with two known ones (8 and 9). Comprehensive spectroscopy techniques were used to determine their structures. Although 1-8 only showed a weak inhibitory effect on the proliferation of the tumor-derived vascular endothelial cells, however, in a former study we found both total steroidal glycoalkaloids from Solanum lyratum (TSGS) and 9 significantly inhibited tumor angiogenesis and its mechanism was linked to its ability to interfere with cell membrane lipid rafts. Lipid rafts are closely related to the functions of tumor-derived exosomes, a vital factor in cancer progression. Thus, we investigated the impacts of TSGS and 9 on the functions of A549-derived exosomes. Our results indicated that A549-derived exosomes can significantly enhance the angiogenesis abilities of human umbilical vein endothelial cells, whereas the intervention of TSGS or 9 significantly inhibited this activity of A549-derived exosomes. These findings suggest that TSGS and 9 exert anti-tumor angiogenesis by inhibiting the pro-angiogenic activity of A549-derived exosomes.

6.
J Mater Chem B ; 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31930242

RESUMO

Localized administration of anti-inflammatory agents benefits patients after myocardial infarction (MI) by repressing/modulating inflammatory response of the MI region and thus accelerating repair of the impaired tissues. Colchicine (Col), an ancient natural drug, has excellent anti-inflammatory effects; however, its utilization is strictly limited due to its severe systemic toxicity and narrow therapeutic window. In this study, we developed an intramyocardial delivery system of Col using an injectable, thermosensitive poly(lactide-co-glycolide)-poly(ethylene glycol)-poly(lactide-co-glycolide) (PLGA-PEG-PLGA) polymer hydrogel as the vehicle for the treatment of MI while minimizing its systemic toxicity. The aqueous PLGA-PEG-PLGA solution loaded with Col (Col@Gel) underwent a sol-gel transition at 35 °C and maintained a gel state at body temperature. Col was released from the Col@Gel in an initial burst followed by a sustained release manner for over 8 days. The in vitro cell tests showed that the Col@Gel system significantly inhibited macrophage proliferation and migration. In a mouse model of MI, a single intramyocardial administration of the Col@Gel effectively alleviated cardiac inflammation, inhibited myocardial apoptosis and fibrosis, improved cardiac function and structure, and increased mouse survival without inducing severe systemic toxicity, which was observed following intraperitoneal administration of Col solution. These results suggested that the Col@Gel system is a reliable drug delivery system for the sustained local release of Col and has great potential as an anti-inflammatory therapy for the treat of MI.

7.
Nat Immunol ; 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31932812

RESUMO

Cancer cells subvert immune surveillance through inhibition of T cell effector function. Elucidation of the mechanism of T cell dysfunction is therefore central to cancer immunotherapy. Here, we report that dual specificity phosphatase 2 (DUSP2; also known as phosphatase of activated cells 1, PAC1) acts as an immune checkpoint in T cell antitumor immunity. PAC1 is selectively upregulated in exhausted tumor-infiltrating lymphocytes and is associated with poor prognosis of patients with cancer. PAC1hi effector T cells lose their proliferative and effector capacities and convert into exhausted T cells. Deletion of PAC1 enhances immune responses and reduces cancer susceptibility in mice. Through activation of EGR1, excessive reactive oxygen species in the tumor microenvironment induce expression of PAC1, which recruits the Mi-2ß nucleosome-remodeling and histone-deacetylase complex, eventually leading to chromatin remodeling of effector T cells. Our study demonstrates that PAC1 is an epigenetic immune regulator and highlights the importance of targeting PAC1 in cancer immunotherapy.

8.
Food Chem ; 308: 125674, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31669944

RESUMO

Cadmium-contaminated rice has been a serious food safety issue in China. In this research, carboxymethyl rice starch (CMS) from cadmium-contaminated rice and native rice was prepared to remove the cadmium in rice. The preparation of native rice starch (NRS) and starch from cadmium-contaminated rice (Cd-CRS) was similar, and carboxymethyl starch was prepared following the same steps. A single factor experiment was performed to obtain the carboxymethyl starch prepared under the optimal conditions. Cadmium content was reduced from 0.38 mg/kg to 0.04 mg/kg after alkalization. The physical properties, including particle size, degree of crystallinity, water absorption and freeze-thaw stability, of NRS and Cd-CRS and their carboxymethyl starches were studied. The results showed that the cadmium was significantly removed after extracting starch from cadmium-contaminated rice by alkalization and carboxymethylation. Then, starch samples and carboxymethyl starch samples were characterized. All results showed no obvious difference between Cd-CMS and NCMS, indicating that carboxymethyl starch from cadmium-contaminated rice could be widely used in both food and nonfood industries.


Assuntos
Cádmio/análise , Oryza/química , Amido/análogos & derivados , Contaminação de Alimentos , Inocuidade dos Alimentos , Tamanho da Partícula , Amido/química , Água
9.
Environ Int ; 135: 105348, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31884131

RESUMO

A total of 41 play mats made from different raw materials, such as polyethylene (PE), ethylene-vinyl acetate copolymer (EVA), chemical crosslinked polyethylene (XPE), and polyvinyl chloride (PVC), were obtained from Chinese markets and analyzed for flame retardants. Polybrominated diphenyl ethers (PBDEs) and their replacements, organophosphate esters (OPEs), were measured and the associated exposure risks for children were evaluated. The levels (range; median) of OPEs (6.6-7400; 200 ng g-1) were generally 1-2 orders of magnitude higher than those of PBDEs (0.13-72; 13 ng g-1), consistent with the production and usage trends of flame retardants. The concentrations of both PBDEs and OPEs were the lowest in XPE mats (0.13-5.6; 3.3 ng g-1 for PBDEs and 6.6-320; 47 ng g-1 for OPEs) compared to the other three types. Concentration comparison and compositional analysis suggested that PBDEs and OPEs in play mats were most probably from leaching of raw materials, during production, storage, and/or transport. Children's exposure to PBDEs and OPEs from play mats was estimated for three pathways, i.e., dermal contact, inhalation, and hand-to-mouth ingestion. The combined exposure was 5-6 orders of magnitude lower than the established reference dose values, suggesting no obvious health concern regarding the occurrence of PBDEs and OPEs in play mats. Nevertheless, selection of less contaminated, i.e., XPE mats among those under investigation, by consumers is strongly recommended to minimize any potential exposure risk.

10.
J Cell Physiol ; 235(3): 2937-2946, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31535380

RESUMO

Numerous studies have reported that long noncoding RNA (lncRNA) dysregulation is involved in the progression of many malignant tumors, including glioma. The lncRNA ZNFX1 antisense RNA 1 (ZFAS1) plays an oncogenic role in various malignant tumors, such as gastric cancer and hepatocellular carcinoma. However, the underlying molecular mechanism of ZFAS1 in glioma has not been fully clarified. In this study, we found that the expression of ZFAS1 was upregulated in both glioma tissues and cell lines. Functional experiments revealed that ZFAS1 promoted glioma proliferation, migration and invasion, and increased resistance to temozolomide in vitro. By using online databases, RNA pull-down assays and luciferase reporter assays, ZFAS1 was demonstrated to act as a sponge of miR-150-5p. Furthermore, proteolipid protein 2 (PLP2) was shown to be the functional target of miR-150-5p. Rescue experiments revealed that ZFAS1 regulated the expression of PLP2 by sponging miR-150-5p. Finally, a xenograft tumor assay demonstrated that ZFAS1 promoted glioma growth in vivo. Our results showed that ZFAS1 promoted glioma malignant progression by regulating the miR-150-5p/PLP2 axis, which may provide a potential therapeutic target for the treatment of glioma.

11.
Bioresour Technol ; : 122487, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31812598

RESUMO

Liberating high value-added compounds ferulic acid (FA) and xylo-oligosaccharides (XOSs) from agricultural residues is a promising strategy for the utilization of lignocellulose. In this study, a bifunctional xylanase/feruloyl esterase from bacterial consortium EMSD5 was heterogeneously expressed in Escherichia coli. Depending on the inter-domain synergism of the recombinant enzyme rXyn10A/Fae1A, high yields of FA (2.78, 1.82, 1.15 and 7.31 mg/g substrate, respectively) were obtained from 20 mg in-soluble wheat arabinoxylan, de-starched wheat bran, ultrafine-grinding corn stover and steam-exploded corncob. Meanwhile, 3.210, 1.235, 1.215 and 0.823 mg xylose/XOSs were also released. For cost-saving enzyme production, we firstly constructed a recombinant E. coli, which could secrete the bifunctional xylanase/feruloyl esterase out of cells. When the recombinant E. coli was cultured in medium containing 200 mg de-starched wheat bran, 474 µg FA and 18.2 mg xylose/XOSs were also detected. Hence, rXyn10A/Fae1A and the recombinant strain showed great applied potential for FA and XOSs production.

12.
Stem Cells Int ; 2019: 3621314, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31814832

RESUMO

Background: Tbx18 is a vital transcription factor involved in embryonic sinoatrial node (SAN) formation process but is gradually vanished after birth. Myocardial injection of lentiviral Tbx18 converts cardiomyocytes into pacemaker-like cells morphologically and functionally. In this in vitro and in vivo study, genetical modification of porcine bone mesenchymal stem cells (BMSCs) by recapturing the Tbx18 expression creates a biological pacemaker which was examined. Methods: The isolated porcine BMSCs were transfected with lentiviral Tbx18, and the induced pacemaker-like cells were analyzed using real-time polymerase chain reaction and western blotting to investigate the efficiency of transformation. Then, the induced pacemaker-like cells were implanted into the right ventricle of the SAN dysfunction porcine model after the differentiation process. Biological pacemaker activity and ectopic pacing region were tested by an electrocardiograph (ECG) monitor. Results: The isolated porcine BMSCs expressed specific surface markers of stem cells; meanwhile, the expression of myocardial markers was upregulated significantly after lentiviral Tbx18 transfection. The porcine SAN dysfunction model was constructed by electrocoagulation using a surgical electrotome. The results showed that the mean heart beat (HR) of BMSCs-Tbx18 was significantly higher than that of BMSCs-GFP. An ectopic pacing region was affirmed into the right ventricle by ECG after implantation of BMSCs-Tbx18. Conclusion: It was verified that Lenti-Tbx18 is capable of transducing porcine BMSCs into pacemaker-like cells. Genetically modified porcine BMSCs by lentiviral Tbx18 could create a biological pacemaker. However, further researches in large-scale animals are required to rule out unexpected complications prior to application in clinical practice.

13.
Sensors (Basel) ; 19(24)2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31817363

RESUMO

Compared with the previous GPS satellites, the first GPS III satellite adds a new civil signal L1C to the signal components of the L1 frequency in addition to the improvement of positioning accuracy, anti-interference ability, and service life. The selection and combination of signal modulation and multiplexing methods will affect the power ratio and phase relationship in the process of signal transmission. In the distribution of constellation of different modulation modes, the signal amplitudes of different signal constellation points will be affected by the nonlinear amplifiers of satellites. The analysis can assess its impact on navigation performance. The iGMAS monitoring and evaluation center of the 54th Research Institute of China Electronics Technology Group Corporation uses the low-distortion data acquisition and processing platform and refined signal software receiving processing algorithm of the iGMAS monitoring and evaluation center to complete the signal acquisition of the first satellite of GPS III over China, and processes accordingly for its signal modulation mode. Compared with the previous generation GPS of old system signals, it is found that the GPS signal of the new system not only adds the L1C frequency, but also the constant envelope multiplexing mode of the L1 frequency signal, and the power ratio of the internal signal components are also adjusted.

14.
Int J Legal Med ; 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31802193

RESUMO

Custodial deaths refer to the death of an individual who is in prison, a detention center, or a police station. The present study aims to retrospectively analyze cases of custodial deaths examined at Tongji Medico Legal Expertise Center in Hubei (TMECH). A total of 172 out of 5853 cases were screened at TMECH from January 1999 to December 2016. Male preponderance was observed in 172 cases (male-female ratio: 5:1). Natural deaths accounted for the majority (70.93%), followed by suicide (16.28%), accidents (3.49%), homicides (4.65%), and undetermined causes (4.65%). The most common natural cause was cardiovascular disease. Custodial deaths occurred more frequently in prisons and detention houses than in police cells (63%, 63%, and 46%, respectively). Among the 172 cases, 105 deaths occurred after resuscitation failure despite the individual being sent to the hospital. The average age across cases was 36.3 years, and 90% of the deceased were aged under 50 years. Since there is no officially reported data regarding the prevalence of causes and manners of custodial deaths in China, our analysis contributes to enhancing the understanding of such deaths in central China and serves as a reference for law enforcement to develop a prevention program to reduce incidents of mortality in custody.

15.
Sci Prog ; : 36850419878024, 2019 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-31829872

RESUMO

With strong demands of energy-saving and environment-friendly vehicles, hydraulic hybrid powertrain is a suitable solution for urban transportation. This article proposes a novel hydraulic hybrid vehicle with wheel motors to improve vehicle power performance and fuel economy. A forward-looking simulation model of the vehicle is built. System parameters are determined according to the power performance demands. A smaller engine is chosen, the peak power of which is reduced by 11.96%. The simulation model is calibrated and verified by experimental tests on the designed test bench. Parameterized simulation results indicate that the acceleration time 0-100 km/h of the designed vehicle is decreased by 36.3% from 19.63 to 12.5 s compared with the conventional vehicle. The maximum vehicle speed is 140 km/h, and the maximum gradeability is 29%. When the engine works in economy mode, fuel consumption is decreased by 35.59% from 15 to 9.66 L per 100 km on the Urban Dynamometer Driving Schedule cycle compared with the conventional vehicle.

16.
Sci Rep ; 9(1): 20034, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31882989

RESUMO

Resistance of cancer cells to chemotherapy is a significant clinical concern and mechanisms regulating cell death in cancer therapy, including apoptosis, autophagy or necrosis, have been extensively investigated over the last decade. Accordingly, the identification of medicinal compounds against chemoresistant cancer cells via new mechanism of action is highly desired. Autophagy is important in inducing cell death or survival in cancer therapy. Recently, novel autophagy activators isolated from natural products were shown to induce autophagic cell death in apoptosis-resistant cancer cells in a calcium-dependent manner. Therefore, enhancement of autophagy may serve as additional therapeutic strategy against these resistant cancers. By computational docking analysis, biochemical assays, and advanced live-cell imaging, we identified that neferine, a natural alkaloid from Nelumbo nucifera, induces autophagy by activating the ryanodine receptor and calcium release. With well-known apoptotic agents, such as staurosporine, taxol, doxorubicin, cisplatin and etoposide, utilized as controls, neferine was shown to induce autophagic cell death in a panel of cancer cells, including apoptosis-defective and -resistant cancer cells or isogenic cancer cells, via calcium mobilization through the activation of ryanodine receptor and Ulk-1-PERK and AMPK-mTOR signaling cascades. Taken together, this study provides insights into the cytotoxic mechanism of neferine-induced autophagy through ryanodine receptor activation in resistant cancers.

17.
Biochem Pharmacol ; 172: 113762, 2019 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-31843541

RESUMO

IKK-ß is indispensable for inflammatory osteolysis, the functional residues of IKK-ß are therapeutic drug targets for developing inhibitors to treat multiple diseases now. Thus it remains appealing to find the new residues of IKK-ß to influence osteoclasts for alleviating bone loss diseases such as rheumatoid arthritis (RA). By employing IKK-ß cysteine 46-A transgenic (IKK-ßC46A) mice, we found that mutation of cysteine 46 to alanine in IKK-ß exacerbated inflammatory bone destruction in vivo, and increased osteoclast differentiation and bone resorption ex vivo and in vitro. Consistent with these, IKK-ß kinase activity as well as c-Fos, NFATc1 were up-regulated in bone marrow macrophages (BMMs) from IKK-ßC46A mice during RANKL-induced osteoclastogenesis. Of interesting, we further identified and demonstrated that the expressions of mPGES-1 and caveolin-1 were heightened in BMMs of IKK-ßC46A mice compared to those in WT mice in RANKL-induced osteoclastogenesis. Together, it revealed that mutating cysteine 46 in IKK-ß could increase caveolin-1 and mPGES-1 expression to facilitate osteoclast differentiation and osteolysis. Cysteine 46 can serve as a novel target in IKK-ß for designing inhibitors to treat osteolysis.

18.
Medicine (Baltimore) ; 98(51): e18273, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31860974

RESUMO

BACKGROUND: Methionine synthase reductase gene (MTRR A66G) polymorphism and methionine synthase gene (MTR A2756G) polymorphism have shown an association with idiopathic male infertility risk in several ethnic populations. However, their small sample sizes and inconsistent outcomes have prevented strong conclusions. We performed a meta-analysis with published studies to evaluate the associations of the 2 single nucleotide polymorphisms (SNPs) and idiopathic male infertility risk. METHODS: A thorough literature search was performed up to Jun 21, 2019 with Medline, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), China Biology Medical literature (CBM), China Science and Technology Journal Database (VIP), and Chinese literature (Wan Fang) databases. Odds ratio (OR) and 95% confidence interval (95% CI) were used to assess the strength of associations. RESULTS: Seventeen studies including 3269 cases and 3192 controls met the inclusion criteria. Our meta-analysis showed that the MTR A2756G mutation may contribute to genetic susceptibility to the risk of idiopathic male infertility in Non-Asians, but not to Asian population, whereas the MTRR A66G polymorphism may be unrelated to idiopathic male infertility in both Non-Asian and Asian populations. In the stratified analysis by infertility type, the MTR A2756G polymorphism was a risk factor for both non-obstructive azoospermia (NOA) and oligoasthenoteratozoospermia (OAT) patients. However, the MTRR A66G polymorphism is associated with risk for OAT in Asian, but not in Non-Asian population. CONCLUSION: This meta-analysis suggested that the MTR A2756G and MTRR A66G polymorphisms were risk factors for idiopathic male infertility. Studies with larger sample sizes and representative population-based cases and well-matched controls are needed to validate our results.


Assuntos
5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/genética , Ferredoxina-NADP Redutase/genética , Infertilidade Masculina/genética , Polimorfismo de Nucleotídeo Único/genética , Predisposição Genética para Doença/genética , Humanos , Masculino , Fatores de Risco
19.
Br J Neurosurg ; : 1-3, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31718304

RESUMO

We report a rare case of a rapidly calcified subdural hematoma (SDH) occurring 15 days after craniotomy in an adolescent. It suggests that calcification of a SDH may occur not only in the chronic stage but also in the subacute stage and may appear in subdural hematomas (SDHs) after craniotomy.

20.
J Healthc Eng ; 2019: 9724589, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31781361

RESUMO

Predicting the outcome after a cancer diagnosis is critical. Advances in high-throughput sequencing technologies provide physicians with vast amounts of data, yet prognostication remains challenging because the data are greatly dimensional and complex. We evaluated Wnt/ß-catenin, carbohydrate metabolism, and PI3K-Akt signaling pathway-related genes as predictive features for classifying tumors and normal samples. Using differentially expressed genes as controls, these pathway-related genes were assessed for accuracy using support-vector machines and three other recommended machine learning models, namely, the random forest, decision tree, and k-nearest neighbor algorithms. The first two outperformed the others. All candidate pathway-related genes yielded areas under the curve exceeding 95.00% for cancer outcomes, and they were most accurate in predicting colorectal cancer. These results suggest that these pathway-related genes are useful and accurate biomarkers for understanding the mechanisms behind cancer development.

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