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1.
Huan Jing Ke Xue ; 41(6): 2688-2697, 2020 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608784

RESUMO

Enrofloxacin (ENR), a fluoroquinolones antibiotic, is widely used in the medical and aquaculture fields. Its residues in surface waters in China are high. However, few studies have evaluated both its toxicity to phytoplankton and the degradation or removal by microalgae. In this study, the growth, photosynthetic activity, and exopolysaccharides (EPS) of freshwater micro-green algae Dictyosphaerium sp. and the dynamics of ENR concentrations (0, 5, 25, 50, and 100 mg·L-1) were studied through an exposure experiment for 12 days. Results showed that the biomass and photosynthetic pigment content of Dictyosphaerium sp. increased with increasing exposure time in each treatment; however, it showed a significant inhibitory effect on the growth and pigment accumulation of Dictyosphaerium sp. compared with the control group (P<0.01). The LC50 of ENR to Dictyosphaerium sp. was (241.29±7.33) mg·L-1 after 96-h exposure, indicating that Dictyosphaerium sp. could adapt to the stress conditions of high concentration ENR. Meanwhile, when the concentration of enrofloxacin was<5 mg·L-1, it was found to promote the maximum photosynthetic rate (Fv/Fm) of Dictyosphaerium sp. On the contrary, when the concentration of enrofloxacin was>5 mg·L-1, photosynthetic inhibition was observed (P<0.01). The actual photosynthetic rate (Yield) and the maximum electron transfer rate (ETRmax) showed a trend of initially decreasing and then increasing in 12 days. It can gradually adapt to the stress conditions and recover certain photosynthetic activity after 6 days' exposure. In addition, ENR can also stimulate the EPS (RPS and CPS) release. At the end of the experiment, the removal rates of ENR in the four control groups (no algae addition groups) (5, 25, 50, and 100 mg·L-1ENR) were 7.27%, 5.56%, 5.30%, and 4.88%, respectively, while the removal rates of the treatment groups were 3.21, 3.01, 2.69, and 2.83 times of the no algae groups, indicating that Dictyosphaerium sp. had a significant promoting effect on the removal of ENR (P<0.01). Overall, our results can provide new insights for the understanding of the ecological toxicity of fluoroquinolone antibiotics to primary producers in the aquatic system and also provide new ideas for the ecological removal of antibiotic residues in water bodies and the biological resource utilization of freshwater microalgae.

2.
Lipids Health Dis ; 19(1): 150, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32580730

RESUMO

BACKGROUND: Inflammation and oxidative stress play predominant roles in the initiation and progression of ischaemia/reperfusion (I/R) injury, with nuclear factor kappa B (NF-κB) serving as a crucial mediator. Overexpression of the inhibitor of κB alpha (IκBα) gene is hypothesized to have protective effects against apoptosis and autophagy in cardiomyocytes subjected to hydrogen peroxide (H2O2) by inhibiting the NF-κB pathway. METHODS: The IκBαS32A, S36A gene was transfected via adeno-associated virus serotype 9 (AAV9) delivery into neonatal rat ventricular cardiomyocytes (NRVMs) prior to H2O2 treatment. NRVMs were divided into control, H2O2, GFP + H2O2, IκBα+H2O2, and pyrrolidine dithiocarbamate (PDTC) + H2O2 groups. Nuclear translocation of the NF-κB p65 subunit was evaluated by immunofluorescence and Western blotting. Cell viability was assessed by Cell Counting Kit-8 assay. Supernatant lactate dehydrogenase (LDH) and intracellular malondialdehyde (MDA) were measured to identify H2O2-stimulated cytotoxicity. Apoptosis was determined by Annexin V-PE/7-AAD staining, and the mitochondrial membrane potential (ΔΨm) was detected by JC-1 staining. Western blotting was used to detect apoptosis- and autophagy-related proteins. RESULTS: IκBα transfection significantly increased cell viability and ΔΨm but decreased the supernatant LDH and cellular MDA levels in cardiomyocytes exposed to H2O2. Meanwhile, IκBα overexpression decreased H2O2-induced apoptosis by upregulating the Bcl-2/Bax ratio and reduced autophagy by downregulating the expression of Beclin-1 and the LC3-II/LC3-I ratio. These effects partly accounted for the ability of IκBα to inhibit the NF-κB signalling pathway, as evidenced by decreases in p65 phosphorylation and nuclear translocation. Indeed, the effects of inactivation of NF-κB signalling with the specific inhibitor PDTC resembled the cardioprotective effects of IκBα during H2O2 stimulation. CONCLUSION: IκBα overexpression can ameliorate H2O2-induced apoptosis, autophagy, oxidative injury, and ΔΨm loss through inhibition of the NF-κB signalling pathway. These findings suggest that IκBα transfection can result in successful resistance to oxidative stress-induced damage by inhibiting NF-κB activation, which may provide a potential therapeutic target for the prevention of myocardial I/R injury.

3.
Biochem Pharmacol ; 178: 114064, 2020 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-32492449

RESUMO

Osteosarcoma (OS) is the most common solid tumor of the bone that most often affects adolescents. The introduction of chemotherapy for the treatment of OS has largely improved the survival rates of patients with localized tumors. However, the 5-year survival rate of OS patients with relapsed or metastatic disease is only 10 to 20%. In this study, the antimicrobial peptide tilapia piscidin 3 (TP3), isolated from Nile tilapia (Oreochromis niloticus), was treated to OS MG63 cells. Our findings showed that TP3 concentration as low as 1 µM induced significant inhibition of cell viability and increased DNA fragmentation, as determined by the MTT and TUNEL assays, respectively. The protein expression levels of cleaved caspases 3/9 were increased. An in situ live-cell time-lapse video and cell tomographic microscopy images showed cellular blebbing, shrinkage, nuclear fragmentation, and chromatin condensation, with the formation of beaded apoptopodia. Moreover, there were significant increase in the production of TP3-induced mitochondrial and cellular reactive oxygen species (ROS), as well as down-regulated mitochondrial oxygen consumption and extracellular acidification rates. Additionally, TP3 enhanced mitochondrial fission, whereas fusion was attenuated. Furthermore, after administration of the mitochondria targeted antioxidant mitoTempo, TP3-induced ROS oxidant levels and alterations in cleaved caspases 3/9 expression were rescued. TP3 promoted mitochondria-modulated intrinsic apoptosis through the induction of ROS production, activation of caspases 3/9, and the down-regulation of mitochondrial oxygen consumption and extracellular acidification rates, suggesting that TP3 has potential as an innovative alternative for OS treatment.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32496449

RESUMO

BACKGROUND: Percutaneous compression of the trigeminal ganglion (PCTG) can induce significant hemodynamic perturbations secondary to the trigeminocardiac reflex (TCR). The aim of this study was to investigate the effect of atropine pretreatment on hemodynamic responses during PCTG for trigeminal neuralgia. MATERIALS AND METHODS: A total of 120 patients who received PCTG were randomly assigned to control and atropine groups that were pretreated with saline (n=60) and atropine 0.004 mg/kg intravenously (n=60), respectively. Heart rate (HR) and mean arterial pressure (MAP) were measured at 9 timepoints from before induction of anesthesia until the end of the PCTG procedure; the incidence of TCR was also observed. RESULTS: HR was higher in the atropine compared with control group from the time of skin puncture with the PCTG needle until after the procedure was completed (P<0.05). MAP was also higher in the atropine compared with control group, but only at entry of the needle into the foramen ovale until 1 minute after trigeminal ganglion compression (P<0.05). HR was reduced in both groups during entry of the needle into the foramen ovale and during ganglion compression, but less so in the atropine compared with the control group (P<0.05). MAP increased during PCTG compared with baseline in both groups, but with a larger increase in the atropine group (P<0.05). Two and 52 cases in the control group, and 6 and 1 cases in the atropine group, exhibited a TCR during entry of the needle into the foramen ovale and at ganglion compression, respectively (P<0.05). CONCLUSION: Pretreatment with atropine was effective in most patients at minimizing abrupt reduction in HR during PCTG.

5.
Ying Yong Sheng Tai Xue Bao ; 31(2): 449-458, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32476337

RESUMO

Improper fertilization style is one of the main reasons for low water and fertilizer use efficiency of double-ridge-furrow sowing with the whole plastic film mulching in maize production in the semi-arid area. Understanding the effects of reduction, postponing, and organic fertilizer substitution of nitrogen fertilizer on water and fertilizer use efficiency and yield of maize can provide theore-tical basis for effective management of water and fertilizer in maize production. Based on a 4-year field experiment with three treatments: all fertilizers as base fertilizer under double-ridge-furrow sowing with the whole plastic film mulching (CK), nitrogen fertilizer reduced by 15% and topdres-sing in tasseling stage (RN), 30% of the chemical fertilizer replaced by organic fertilizer and topdressing in tasseling stage (RNM), we measured water consumption characteristics, growth and development, water and fertilizer utilization efficiency of maize. The results showed that fertilization pattern significantly affected water and fertilizer utilization efficiency and yield of maize, which was dependent on annual rainfall. In dry and normal rainfall year, water consumption in pre-flowering stage of RN was decreased by 16.1%-18.8% and that in post-flowering stage was increased by 18.0%-22.2%, while water consumption in pre-flowering and post-flowering stages of RNM did not differ from that in CK. In wet year, water consumption in pre-flowering stage of RN and RNM was decreased by 16.7% and 6.3%, while that in post-flowering stage was increased by 11.4% and 29.7%, respectively. Compared with CK, RN significantly increased the relative content of chlorophyll (SPAD) of maize leaves after topdressing, the biomass in post-flowering stage was increased by 15.6%-44.9%, the ear length, the number and weight of grains per spike and the 100-grain weight were increased significantly, yield was increased by 9.8%-17.0%, and water use efficiency (WUE) was increased by 6.3%-21.4%, with the partial productivities of fertilizer (PEPT), N (PEPTN), P (PEPTP) and K (PEPTK) were all increased significantly. In conclusion, RN could improve water consumption and the SPAD value in post-flowering stage of maize in different precipitation years, increase post-flowering biomass, and optimize the ear character, obviously improve yield, water and fertilizer use efficiency. It was a effective fertilizer management mode with high-efficiency utilization of water and fertilizer under double-ridge-furrow sowing with the whole plastic film mulching in maize in the semi-arid area.


Assuntos
Fertilizantes , Zea mays , Agricultura , China , Nitrogênio , Plásticos , Solo , Água
6.
Clin Appl Thromb Hemost ; 26: 1076029620933008, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32598182

RESUMO

Coronary artery disease (CAD) is a systemic chronic inflammatory disease, and serum fibrinogen and albumin are 2 important factors in systemic inflammation. We aimed to investigate the relationship between the fibrinogen-albumin ratio (FAR) and outcomes in patients with CAD who underwent percutaneous coronary intervention (PCI). All patients were from the Clinical Outcomes and Risk Factors of Patients with Coronary Heart Disease after PCI (CORFCHD-PCI) study, which is a retrospective cohort study (Identifier: ChiCTR-ORC-16010153) that includes a total of 6050 patients with CAD after PCI from January 2008 to December 2016. A total of 5829 patients with CAD after PCI were recruited in the present study. They were divided into 2 groups according to the FAR cutoff value, which was calculated using a receiver operating characteristic curve, a low group (FAR < 0.095, n = 3811), and a high group (FAR ≥ 0.095, n = 2018). The average follow-up time was 35.9 ± 22.6 months. The multivariate Cox proportional hazards model showed that FAR was independently correlated with all-cause mortality (adjusted hazard ratio [HR] = 1.432 [1.134-1.808], P = .003), cardiac mortality (adjusted HR = 1.579 [1.218-2.047], P = .001), major adverse cardiac and cerebrovascular events (adjusted HR = 1.296 [1.125-1.494], P < .001), major adverse cardiac events (adjusted HR = 1.357 [1.170-1.572], P < .001), and heart failure (adjusted HR = 1.540 [1.135-2.091], P = .006). The present study indicated that the FAR was associated with adverse outcomes in patients with CAD who underwent PCI.

7.
J Mol Neurosci ; 2020 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-32529537

RESUMO

The original version of this article unfortunately contained an error in Fig. 3. The image shown for "C57S" was incorrect.

9.
Ying Yong Sheng Tai Xue Bao ; 31(4): 1146-1154, 2020 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-32530189

RESUMO

Based on a 3-year field experiment (2015-2017) with two treatments, annual whole-film mulching (PM) and uncovered (CK), we analyzed the relationship between soil temperature, moisture, and soil hydrothermal movement in semi-arid area. The results showed that freezing-thawing processes under both PM and CK were one-way freezing and two-way melting. Compared with CK, the freezing period in PM treatment was lagged, freezing rate was slowed down, freezing depth was 20 cm shallower, but melting rate was faster, and melting period was shortened by 6-7 days. In freezing period, soil temperature gradients of PM and CK were positive, with heat being transmitted toward top soil layer, and the conduction strength in PM treatment was greater than CK. During the melting period, soil temperature gradient of PM was also positive, with heat being transmitted toward upper soil layer, and that of CK was conversed. Soil water in PM treatment transported to upper soil layer during freezing-thawing period, but it appeared a "down-up-down" movement mode under CK in freezing period, "up-down" in thawing period. There was positively correlation between temperature and moisture gradient in the freezing period under both PM and CK treatments, with closer correlation in PM than CK. During melting period, soil temperature and moisture gradient was positively correlated in PM treatment with soil heat and moisture moved upward synchronously, while that in CK was negatively correlated with soil heat and moisture simultaneously moved to the lower layer soil. Driven by soil temperature and moisture gradient, soil temperature in 0-10 cm, 10-20 cm and 20-30 cm layers increased by 1.13-1.34 ℃, 0.96-1.24 ℃ and 0.89-1.32 ℃, while average soil water content increased by 3.4%-5.6%, 1.4%-2.2% and 6.7%-7.8%, respectively in PM treatment before sowing. Our results indicated that PM could provide water and heat protection for re-greening of winter crop and sowing, emergence and seedling of spring-sown crops in semi-arid areas.


Assuntos
Solo , Zea mays , Agricultura , China , Congelamento , Temperatura , Água
10.
Microbiologyopen ; : e1092, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32537904

RESUMO

Strain S150 was isolated from the tobacco rhizosphere as a plant growth-promoting rhizobacterium. It increased plant fresh weight significantly and lateral root development, and it antagonized plant pathogenic fungi but not phytobacteria. Further tests showed that strain S150 solubilized organic phosphate and produced ammonia, siderophore, protease, amylase, and cellulase, but it did not produce indole-3-acetic acid. Using morphology, physiological characteristics, and multi-locus sequence analysis, strain S150 was identified as Pseudomonas koreensis. The complete genome of strain S150 was sequenced, and it showed a single circular chromosome of 6,304,843 bp with a 61.09% G + C content. The bacterial genome contained 5,454 predicted genes that occupied 87.7% of the genome. Venn diagrams of the identified orthologous clusters of P. koreensis S150 with the other three sequenced P. koreensis strains revealed up to 4,167 homologous gene clusters that were shared among them, and 21 orthologous clusters were only present in the genome of strain S150. Genome mining of the bacterium P. koreensis S150 showed that the strain possessed 10 biosynthetic gene clusters for secondary metabolites, which included four clusters of non-ribosomal peptide synthetases (NRPSs) involved in the biosynthesis of cyclic lipopeptides (CLPs). One of the NRPSs possibly encoded lokisin, a cyclic lipopeptide produced by fluorescent Pseudomonas. Genomic mutation of the lokA gene, which is one of the three structural NRPS genes for lokisin in strain S150, led to a deficiency in fungal antagonism that could be restored fully by gene complementation. The results suggested that P. koreensis S150 is a novel plant growth-promoting agent with specific cyclic lipopeptides and contains a lokisin-encoding gene cluster that is dominant against plant fungal pathogens.

11.
J Clin Pharm Ther ; 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32542736

RESUMO

WHAT IS KNOWN AND OBJECTIVE: The influence of venovenous extracorporeal membrane oxygenation (VV-ECMO) on the population pharmacokinetics (PPK) of vancomycin in recipients after lung transplantation (LTx) is unknown. We investigated whether VV-ECMO influences vancomycin PPK and determined optimal recommended dosage for patients after LTx. METHODS: We tested vancomycin serum concentration and calculated PPK parameters using NONMEM. To check for any potential influence of ECMO on vancomycin PK, we compared ECMO patients with a non-ECMO patient control group, and patients before and after ECMO weaning as self-control to analysed changes in vancomycin PK. Monte Carlo dosing simulation was conducted to explore vancomycin dosing regimens. RESULTS: Nineteen ECMO and 6 non-ECMO lung transplant recipients were enrolled. Vancomycin serum concentrations did not significantly differ between patients with and without ECMO support. Comparison of separate vancomycin population pharmacokinetic models showed that ECMO patients had smaller peripheral compartment volume of distribution (V2 ) [Estimate (relative standard error, RSE, %) 19.7 (12) vs. 22 (17) L, P = .003] than non-ECMO patients. For treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections with MIC ≤ 0.5 µg/mL, venous infusion of 400 mg vancomycin every 8 hours was recommended. For MRSA infection with MIC ≤ 1 µg/mL, the proposed dosage was 600 mg every 8 hours. WHAT IS NEW AND CONCLUSION: Venovenous extracorporeal membrane oxygenation slightly alters vancomycin PK but does not significantly impact vancomycin serum concentration in patients after LTx. Dose adjustment is not necessary for VV-ECMO support. Specific vancomycin dosing regimens with lower nephrotoxicity may benefit LTx recipients with VV-ECMO.

12.
Liver Transpl ; 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32542994

RESUMO

It has been shown that normothermic machine perfusion (NMP), a novel preservation method, is able to assess and resuscitate liver grafts with risk factors. However, there is no consistent criteria for assessment of liver graft with NMP. Ischemia-free liver transplantation (IFLT) includes innovative surgical techniques and NMP, which can protect liver grafts from ischemia throughout organ procurement, preservation and implantation. In our center, 28 human livers from donation after brain death (DBD) were subjected to IFLT between July 2017 and October 2018. Correlation between post-transplant liver function tests with the perfusion parameters, blood gas analysis of perfusate and bile biochemistry were analyzed. During preservation phase, the vascular flow was stable and the lactate level decreased rapidly. The transaminase release in the perfusate was stably low, while the glucose level maintained a high level. The perfusate lactate and aspartate aminotransferase (AST) levels at one hour of perfusion were correlated with the post-transplant peak AST level. There were negative correlations between the portal vein/hepatic artery flow at the end of perfusion and the peak transaminase levels within 7 days post-transplantation. In conclusion, during IFLT, NMP is able to bridge the liver grafts from donors to recipients and can allow the assessment of liver function by perfusion characteristics.

13.
Food Funct ; 11(5): 4456-4470, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32374309

RESUMO

The current work aimed at investigating the effects of the dietary supplementation of N-carbamylglutamate (NCG) or l-arginine (Arg) on the duodenal mitophagy, mitochondrial function, inflammation, and barrier function in suckling lambs suffering from intrauterine-growth-retardation (IUGR). Forty-eight neonate Hu lambs were used in this study: 12 lambs with normal birth weight (NBW: 4.25 ± 0.14 kg) and 36 lambs with IUGR (3.01 ± 0.13 kg). Seven day old lambs were assigned to 4 treatment groups (12 lambs in each group) as follows: control group (CON), IUGR group, IUGR + Arg, and IUGR + NCG. Lambs were fed the experimental diets for 21 days from 7 days to 28 days of age. Compared with IUGR lambs, the Arg or NCG-treated IUGR lambs had a markedly higher duodenal transepithelial electrical resistance (TER) and lower fluorescein isothiocyanate dextran (FD4) (P < 0.05), respectively. The duodenal mitochondrial membrane potential change (ΔΨm), relative mitochondrial DNA (mtDNA) content, adenosine triphosphate (ATP) level, together with the activities of the respiratory complexes I, III, and IV were markedly higher in Arg or NCG-treated IUGR lambs than those in non-supplemented IUGR lambs (P < 0.05). The expressions of the integrity-related proteins (occludin and zonula occludens-1 (ZO-1)), antioxidant- and apoptosis-related proteins (B-cell lymphoma/leukaemia 2 (Bcl2), superoxide dismutase 2 (SOD2), catalase (CAT), and glutathione peroxidase 1 (GPx1)), and the nitric oxide-dependent pathway-related proteins (epithelial NO synthase (eNOS) and inducible NO synthase (iNOS)) were higher in NCG or Arg-supplemented IUGR lambs than those in nontreated IUGR lambs (P < 0.05). The duodenal expressions of the mitophagy-related proteins (microtubule-associated protein light chain 3 (LC3) I, LC3 II, Belin1, PTEN induced putative kinase 1 (PINK1), and Parkin) and the immune function-related proteins (myeloid differentiation factor 88 (MyD88), IL-6, nuclear factor kappa B (p65), toll-like receptor (TLR4) and TNF-α) were reduced (P < 0.05) in NCG or Arg-supplemented IUGR lambs compared with non-supplemented IUGR lambs. These results demonstrated that the dietary supplementation of Arg or NCG enhanced the duodenal barrier function and mitochondrial function, mitigated duodenal inflammation, and suppressed mitophagy in suckling lambs suffering from IUGR.

14.
Int Immunopharmacol ; 84: 106579, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32413742

RESUMO

Hederacoside-C (HDC), a natural compound extracted from the leaves of Hedera helix with inflammation modulatory properties in variety of disorders. In this study, we investigated the latent mechanism of HDC in alleviating of the progress of OA in vitro experiment. The results showed that HDC pretreatment suppressed the advanced glycation end-products (AGEs) induced over-regulation of ROS level and inflammatory factors. Moreover, HDC also downregulate the degradation of ECM induced by AGEs. Mechanistically, the HDC suppressed NF-κB signaling pathway in chondrocyte. To sum up, this study indicated HDC possessed a new potential therapeutic option in osteoarthritis.

15.
J Nanosci Nanotechnol ; 20(10): 6140-6147, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32384963

RESUMO

Detection of blood-borne pathogenic viruses is essential for blood transfusion, and has great significance for epidemiology, as well as clinical practices. Common blood-borne viruses causing infectious diseases include Hepatitis B virus (HBV), Hepatitis C virus (HCV), Human immunodeficiency virus (HIV) and Treponema pallidum (TP). Therefore, multiplex detection of these viruses is more in the line with the needs of clinical testing. Although real-time PCR-based multiplex nucleic acid testing (NAT) was developed for pathogen detection, however, the requirement of multichannel realtime PCR machine increases the instrumental cost and is not suitable for use in resource-limited areas. In this study, we proposed a multiplex and colorimetric assay for detecting viral nucleic acids in blood by using serial invasive reaction assisted gold nanoparticle (AuNPs) probes assembling to identify multiplex PCR amplicons. As low as 2 copies per reaction of HIV and TP targets, and 20 copies per reaction of HBV and HCV targets can be detected. The results can be observed by naked eyes; thus, just a standard PCR machine is required. In addition, the hairpin probe and the AuNPs for signal read out are universal for all the targets, reducing the detection cost. About 20 DNA samples remaining after clinical HBV testing were successfully detected, and the results were consistent with that of commercially available real-time PCR based kit, indicating that this method has a potential for clinical applications.

16.
Appl Opt ; 59(10): C70-C77, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32400567

RESUMO

The spatial resolution of an observation from a geostationary orbiting satellite is usually too coarse to track small scale macroalgae blooms. For macroalgae mapping to benefit from a geostationary orbit's staring monitoring and frequent revisit intervals, we introduced a super-resolution method that reconstructs a high-resolution (HR) image of a region from a sequence of raw geostationary low-resolution images of the same region. We tested our method with GF-4 images at 50 m spatial resolution and demonstrated that the spatial resolution increased to 25 m. In addition, the derived HR image had better image quality characterized by a higher signal-to-noise ratio, clarity, and contrast. The increased spatial resolution and improved image quality improved our ability to distinguish macroalgae patches from the surrounding waters, especially tiny patches of macroalgae, and to precisely delineate the patch boundaries. Lastly, we more accurately estimated the areal coverage of the patches by reducing underestimation of the coverage of tiny patches and overestimation of the coverage of large patches.

17.
BMJ Open ; 10(5): e035374, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32376754

RESUMO

INTRODUCTION: During conventional liver transplantation (CLT), ischaemia-reperfusion injury (IRI) is inevitable and is associated with complications such as early allograft dysfunction (EAD), primary non-function and ischaemic-type biliary lesions. We have established a novel procedure called ischaemia-free liver transplantation (IFLT). The results from a pilot study suggest that IFLT might prevent IRI and yield better transplant outcomes than CLT. The purpose of this study was to further assess the efficacy and safety of IFLT versus CLT in patients with end-stage liver disease. METHODS AND ANALYSIS: This is an investigator-initiated, open-label, phase III, prospective, single-centre randomised controlled trial on the effects of IFLT in patients with end-stage liver disease. Adult patients (aged 18-75 years) eligible for liver transplantation will be screened for participation in this trial and will be randomised between the IFLT group (n=34) and the CLT group (n=34). In the IFLT group, the donor liver will be procured, preserved and implanted with continuous normothermic machine perfusion (NMP). In the CLT group, the donor liver will be procured after a fast cold flush, preserved in 0°C-4°C solution and implanted under hypothermic and hypoxic conditions. Patients in both groups will be managed according to the standard protocol of our centre. The primary end point is the incidence of EAD after liver transplantation. Intraoperative and postoperative parameters of donor livers and recipients will be observed and recorded, and postoperative liver graft function, complications and recipient and graft survival will be evaluated. After a 12-month follow-up of the last enrolled recipient, the outcomes will be analysed to evaluate the safety and efficacy of IFLT versus CLT in patients with end-stage liver disease. ETHICS AND DISSEMINATION: The protocol was reviewed and approved by the Ethics Committee of The First Affiliated Hospital of Sun Yat-sen University. The findings will be disseminated to the public through conference presentations and peer-reviewed scientific journals. TRIAL REGISTRATION NUMBER: ChiCTR1900021158.

19.
Mikrochim Acta ; 187(6): 341, 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32444888

RESUMO

N-Doped silicon quantum dots (N-SiQD) were synthesized using N-[3-(trimethoxysily)propyl]-ethylenediamine and citric acid as silicon source and reduction agent, respectively. The N-SiQD shows a strong blue fluorescence with a high quantum yield of about 53%. It is found that a selective static quenching process occurs between N-SiQDs and Cu2+. Glyphosate can inhibit this phenomenon and trigger the rapid fluorescence enhancement of the quenched N-SiQDs/Cu2+ system due to the specific interaction between Cu2+ and glyphosate. With such a design, a turn-on fluorescent nanoprobe based on N-SiQD/Cu2+ system was established for rapid determination of glyphosate. The determination signal of N-SiQD/Cu2+ was measured at the optimum emission wavelength of 460 nm after excitation at 360 nm. Under optimal conditions, the turn-on nanoprobe showed a linear relationship between fluorescent response and glyphosate concentrations in the range 0.1 to 1 µg mL-1. The limit of determination was calculated to 7.8 ng mL-1 (3σ/S). Satisfactory recoveries were obtained in the determination of spiked water samples, indicating the potential use for environmental monitoring. Graphical abstract Schematic representation of N-SiQD/Cu2+ system for glyphosate determination. Fluorescence quenching of N-SiQDs induced by copper ions and the succedent fluorescent "turn on" triggered by glyphosate.

20.
Biomed Res Int ; 2020: 9045786, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32462032

RESUMO

Purpose: The detection of long noncoding RNA (lncRNA) is a novel method for breast cancer diagnosis. The purpose of this meta-analysis was to evaluate the clinical significance of lncRNAs in identification of human breast cancer. Methods: Electronic databases, including PubMed (176), EMBASE (167), Cochrane Library (4), Web of Science (273), CNKI (41), VIP (18), and wanfang (21), were searched for relevant original articles. Diagnostic capacity of lncRNAs was assessed by pooled sensitivity and specificity, area under the summary receiver operating characteristic curve (AUC), diagnostic odds ratio (DOR), and subgroup and meta-regression analysis. Stata and Meta-Disc software were used to conduct the meta-analysis. Results: 33 articles including 4500 cases were identified in our meta-analysis. lncRNAs sustained a high diagnostic efficacy; the pooled sensitivity, specificity, AUC, and DOR of lncRNAs in differentiating BC from controls were 0.74 (95% CI: 0.69-0.78), 0.78 (95% CI: 0.72-0.83), 0.82 (95% CI: 0.79-0.85), and 10.01 (95% CI: 7.13-14.06), respectively. The subgroup analysis showed that the diagnostic efficacy of lncRNAs in Asian populations was higher than that in Caucasians; lncRNAs in BC were lower than those in TNBC and were higher in plasma and serum specimens than in tissues. In addition, heterogeneity was clearly apparent but was not caused by the threshold effect. Conclusion: This meta-analysis suggested that lncRNAs might be promising biomarkers for identifying breast cancer, and its clinical application warrants further investigation.

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