Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.236
Filtrar
1.
J Clin Monit Comput ; 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32026257

RESUMO

The ability to monitor the physiological effect of the analgesic agent is of interest in clinical practice. Nonstationary changes would appear in photoplethysmography (PPG) during the analgesics-driven transition to analgesia. The present work studied the properties of nonlinear methods including approximate entropy (ApEn) and sample entropy (SampEn) derived from PPG responding to a nociceptive stimulus under various opioid concentrations. Forty patients with ASA I or II were randomized to receive one of the four possible remifentanil effect-compartment target concentrations (Ceremi) of 0, 1, 3, and 5 ng·ml-1 and a propofol effect-compartment target-controlled infusion to maintain the state entropy (SE) at 50 ± 10. Laryngeal mask airway (LMA) insertion was applied as a standard noxious stimulation. To optimize the performance of ApEn and SampEn, different coefficients were carefully evaluated. The monotonicity of ApEn and SampEn changing from low Ceremi to high Ceremi was assessed with prediction probabilities (PK). The result showed that low Ceremi (0 and 1 ng·ml-1) could be differentiated from high Ceremi (3 and 5 ng·ml-1) by ApEn and SampEn. Depending on the coefficient employed in algorithm: ApEn with k = 0.15 yielded the largest PK value (0.875) whereas SampEn gained its largest PK of 0.867 with k = 0.2. Thus, PPG-based ApEn and SampEn with appropriate k values have the potential to offer good quantification of analgesia depth under general anesthesia.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32026273

RESUMO

The transcriptomic response of green microalga Chlorella sorokiniana exposure to environmentally relevant concentration of cadmium(II) (Cd) and 4-n-nonylphenol (4-n-NP) was compared in the present study. Cd and 4-n-NP exposure showed a similar pattern of dys-regulated pathways. The photosystem was affected due to suppression of chlorophyll biosynthesis via down-regulation of Mg-protoporphyrin IX chelatase subunit ChlD (CHLD) and divinyl chlorophyllide a 8-vinyl-reductase (DVR) in Cd group and via down-regulation of DVR in 4-n-NP group. Furthermore, the reactive oxygen species (ROS) could be induced through down-regulation of solanesyl diphosphate synthase 1 (SPS1) and homogentisate phytyltransferase (HPT) in Cd group and via down-regulation of HPT in 4-n-NP group. Additionally, Cd and 4-n-NP would both cause the dys-regulation of carbohydrate metabolism and protein synthesis. On the other hand, there are some different responses or detoxification mechanism of C. sorokiniana to 4-n-NP stress compared to Cd exposure. The increased ROS would cause the DNA damage and protein destruction in Cd exposure group. Simultaneously, the RNA transcription was dys-regulated and a series of changes in gene expressions were observed. This included lipid metabolism, protein modification, and DNA repair, which involved in response of C. sorokiniana to Cd stress or detoxification of Cd. For 4-n-NP exposure, no effect on lipid metabolism and DNA repair was observed. The nucleotide metabolism including pyrimidine metabolism and purine metabolism was significantly up-regulated in the 4-n-NP exposure group, but not in the Cd exposure group. In addition, 4-n-NP would induce the ubiquitin-mediated proteolysis and proteasomal degradation to diminish the misfolded protein caused by ROS and down-regulation of heat shocking protein 40. In sum, the Cd and 4-n-NP could cause the same toxicological effects via the common pathways and possess similar detoxification mechanism. They also showed different responses in nucleotide metabolism, lipid metabolism, and DNA repair.

3.
Cell Biochem Funct ; 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32056246

RESUMO

G-quadruplexes form folded structures because of tandem repeats of guanine sequences in DNA or RNA. They adopt a variety of conformations, depending on many factors, including the type of loops and cations, the nucleotide strand number, and the main strand polarity of the G-quadruplex. Meanwhile, the different conformations of G-quadruplexes have certain influences on their biological functions, such as the inhibition of transcription, translation, and DNA replication. In addition, G-quadruplex binding proteins also affect the structure and function of G-quadruplexes. Some chemically synthesized G-quadruplex sequences have been shown to have biological activities. For example, bimolecular G-quadruplexes of AS1411 act as targets of exogenous drugs that inhibit the proliferation of malignant tumours. G-quadruplexes are also used as vehicles to deliver nanoparticles. Thus, it is important to identify the factors that influence G-quadruplex structures and maintain the stability of G-quadruplexes. Herein, we mainly discuss the factors influencing G-quadruplexes and the synthetic G-quadruplex, AS1411. SIGNIFICANCE OF THE STUDY: This review summarizes the factors that influence G-quadruplexes and the functions of the synthetic G-quadruplex, AS1411. It also discusses the use of G-quadruplexes for drug delivery in tumour therapy.

4.
BMC Ophthalmol ; 20(1): 44, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32013948

RESUMO

BACKGROUND: Rapamycin (RAPA) is a potent angiogenic inhibitor and the aim of this study is to identify the inhibitory effect of RAPA on retinal neovascularization (RNV) in experimental oxygen-induced retinopathy (OIR). METHODS: Forty-two 7-day-old C57BL/6 J mice were randomly divided into normoxia control group (14 mice), OIR group (14 mice), and rapamycin (RAPA) group. OIR model was induced in OIR and RAPA group. Vehicle and RAPA (2 mg/kg/d) was injected intraperitoneally daily from postnatal day 12 (P12) in OIR and RAPA groups, respectively. RNV was evaluated using fluorescence angiography and histopathology on P17. Non-perfused areas of retina were analyzed by Image-Pro plus 6.0 software. Retinal expression of cyclin D1 was detected both at mRNA and protein levels. RESULTS: RAPA treatment significantly decreased RNV, non-perfused areas and number of endothelial cell nuclei breaking through the internal limiting membrane (ILM) in OIR mice. Moreover, RAPA decreased activation of cyclin D1 in retina caused by OIR. CONCLUSION: RAPA can inhibit RNV by downregulating the expression of cyclin D1, which indicates its therapeutic potential in treating RNV-related diseases.

5.
Nanoscale ; 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32043104

RESUMO

Nanoparticles (NPs) will inevitably interact with proteins and form protein coronas once they are exposed to biological fluids. This conventional model for nano-bio interactions has been used for over twenty years. Growing numbers of new nanomaterials are emerging every year. Among them, noble metal nanoclusters (NMNCs) are new types of fluorescent nanomaterials with considerable advantages in biomedical applications. Compared with NPs (typically >10 nm) like Au NPs, carbon nanotubes, etc., NMNCs have ultrasmall sizes (∼2 nm), so when NMNCs are exposed to biological milieu, will they form protein coronas like NPs? Due to a lack of characterization techniques for ultrasmall nanoparticles (USNPs), to date, studies on the binding stoichiometries of USNPs to proteins have been heavily hampered. To address this challenge, we combined the characteristics of various methods and selected human serum albumin (HSA) and transferrin (Trf) as model proteins to study their interactions with dihydrolipoic acid (DHLA) protected gold nanoclusters (DHLA-AuNCs). Steady-state fluorescence, transient fluorescence spectroscopy and isothermal titration calorimetry (ITC) were used to study the thermodynamic parameters (K, ΔH, ΔS, ΔG) and interaction mechanisms. The results showed that the intrinsic fluorescence of both proteins was quenched by DHLA-AuNCs, and the quenching process of HSA was an endothermic dynamic process. In contrast, the quenching process of Trf was an exothermic static process. The combination of ITC, agarose gel electrophoresis (AGE) and zeta potential showed that one HSA could bind 8 ± 1 DHLA-AuNCs and one Trf could bind 7 ± 2 DHLA-AuNCs, which was quite different from the conventional model of protein coronas. Based on these findings, the "protein complex" was termed for proteins upon binding with USNPs. Dynamic light scattering (DLS), transmission electron microscopy (TEM), and atomic force microscopy (AFM) showed that DHLA-AuNCs could induce the agglomeration of proteins. Circular dichroism (CD) and synchronous fluorescence spectroscopy showed that DHLA-AuNCs had a very minor effect on the secondary structures of HSA and Trf, which demonstrated the good biocompatibility of DHLA-AuNCs at the molecular scale. This work has shed light on a new interaction model beyond the protein corona, indicating a possible biological identity of USNPs.

6.
Addict Biol ; : e12875, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32031744

RESUMO

The development of opioid addiction involves DNA methylation. Accordingly, the DNA demethylation, induced by ten-eleven translocation (Tet) enzymes, may represent a novel approach to prevent opioid addiction. The present study examined the role of TET1 and TET3 in the development of morphine-seeking behavior in rats. We showed that 1 day of morphine self-administration (SA) training upregulated TET3 but not TET1 expression in the hippocampal CA1. With 7 days of morphine SA training, the expression of TET3 in the CA1 returned to the baseline level, while the TET1 expression was downregulated. No change of TET1 and TET3 in the nucleus accumbens shell was observed in morphine SA trained rats, or in the yoked morphine rats, or in rats trained for saccharin SA. Furthermore, we found that knocking down TET3 expression in the CA1 accelerated the acquisition of morphine SA, while overexpression of the catalytic domain of TET1 in the CA1 attenuated the acquisition. Together, these findings suggest that TET1 and TET3 in the CA1 are important epigenetic modulators involved in the morphine-seeking behavior and provide a new strategy in the treatment of opioid addiction.

7.
Environ Int ; 136: 105457, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31926438

RESUMO

A novel sulfidogenic acid mine drainage (AMD) treatment system with a sulfur reduction process was developed. During the 220-d operation, >99.9% of 380-mg/L ferric, 150-mg/L aluminum, 110-mg/L zinc, 20-mg/L copper and 2.5-mg/L lead ions, and 42.6-44.4% of 100-mg/L manganese ions in the synthetic AMD were step-by-step removed in the developed system with three pre-posed metal precipitators and a sulfur reduction reactor. Among them, zinc, copper and lead ions were removed by the biogenic hydrogen sulfide that produced through elemental sulfur reduction; while ferric, aluminum and manganese ions were removed by the alkali precipitation. Compared with the reported sulfate reduction reactors, the sulfur reduction reactor significantly reduced the chemical cost by 25.6-78.9% for sulfide production, and maintained a high sulfide production rate (1.12 g S2-/L-d). The pH level in the sulfidogenic reactor driven by sulfur-reducing bacteria posed a significant effect on the sulfide production rate. Under a nearly neutral condition (pH 7.0-7.5), elemental sulfur dissolved into polysulfide to increase the bioavailability of S0. At acidic conditions (pH < 6.0), polysulfide formation was limited and sulfate reduction became dominant. Therefore, maintaining the sulfidogenic reactor driven by sulfur-reducing bacteria at neutral condition is essential to realize high-rate and low-cost AMD treatment. Moreover, the escape of residual hydrogen sulfide from the system was eliminated by employing a 17% recirculation from effluent to the sulfidogenic reactor.

8.
J Colloid Interface Sci ; 565: 77-85, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31935587

RESUMO

Carbon dots (CDs) is a class of zero-dimensional carbon nanomaterials with favorable stability and optical properties. However, CDs in solid state often suffer from fluorescence quenching due to π-π stacking of conjugated systems, like most small molecules or organic dyes. Herein, we prepared the CDs that generate bright yellow luminescence in solid state without any additional matrix, meanwhile the solid CDs are inclined to assembly into spherical structure. While the CDs are dissolved in aqueous solution, the photoluminescence (PL) emission from blue to green can be realized by regulating the concentration of CDs. With the concentration increasing, the self-assembly behavior of CDs is observed in solution, which leads to the bathochromic shift of photoluminescence. Besides, the mechanism of PL conversion in this process was proposed based on the characterization results, that with the concentration of CDs rising in solution, π-π interaction was restrained while electron redistribution was induced. Consequently, a localized state II caused by electron rearrangement gradually becomes the predominant emission state, resulting in the PL emission shifting to long-wavelength region. Moreover, CDs have shown favorable potentials in the field of anti-counterfeit and multicolor bioimaging, making the CDs highly attractive for a wide variety of applications.

9.
Water Res ; 171: 115453, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31918385

RESUMO

This paper discusses the abiotic and biotic processes in the in-situ control of biogenic hydrogen sulfide generated from microbial sulfate reduction by ferric (FeIII) (hydr)oxides (FeOOH) granules in the sediments of polluted urban waters. Granular ferric hydroxide (GFH, ß-FeOOH) and granular ferric oxide (GFO, α-FeOOH) dosed in the organic- and sulfate-rich sediments had 180% and 19% higher sulfide removal capacities than those used for the purely abiotic removal of dissolved sulfide, respectively. The enhancement was attributable to the involvement of the biotic pathways, besides the abiotic pathways (mainly sulfide oxidation). The FeOOH granules stimulated the microbial reduction of surface FeIII by iron-reducing bacteria (e.g., Desulfovibrio and Carnobacterium), and increased the microbial sulfate reduction by 24%-30% under an organic-rich condition, likely due to the enhanced organic fermentation. The microbial iron reduction significantly enhanced the removal of the formed biogenic hydrogen sulfide through increasing sulfide precipitation because it remarkably promoted the release of Fe2+ ions from the granule surface, likely due to the involvement of siderophores as ligands. This biotic pathway led to the formation of amorphous FeS(s) as a major sulfur product (56%-81%), instead of elemental sulfur. The enhancement in the sulfide control performance was much more pronounced when the poorly ordered GFH was used, because of the faster Fe2+ release, compared to the highly ordered GFO. The abiotic and biotic mechanisms elucidated in this study provide insights into the iron-sulfur chemistry in the sediments of various polluted waters (e.g., storm drains, urban rivers, and estuary), where the manually-dosed and naturally-occurring FeIII (hydr)oxides control biogenic hydrogen sulfide.


Assuntos
Compostos Férricos , Sulfeto de Hidrogênio , Sedimentos Geológicos , Ferro , Oxirredução , Rios , Poluição da Água
10.
Int J Biol Macromol ; 147: 453-462, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31923519

RESUMO

Due to the favorable stability, water solubility and good biocompatibility, carbon dots have attracted much attention. Herein, a novel nitrogen-doping bifunctional carbon dots (N-BCDs) with ultra-highly quantum yield (QYabs = 70.4%) is prepared through microwave-assisted method. 50 µg/mL of N-BCDs emit intense fluorescence in HeLa and GES-1 cells with negligible cytotoxicity. In addition, effective inhibition of N-BCDs to human insulin (HI) fibrillation is observed even at 10:1 (mass ratio of HI: N-BCDs) by ThT fluorescence, CD assay and TEM. N-BCDs prevent HI from fibrillation with prolonged lag time and reduced fluorescent intensity at equilibrium, regardless of the addition time of N-BCDs (HI: N-BCDs = 1:1, mass ratio), which has been rarely reported before. Furthermore, the morphology of final HI fibrils is shorter and thinner in the presence of N-BCDs. Mechanism studies reveal that the enhanced hydrogen bond between HI monomers and N-BCDs inhibits nucleation during the lag stage (Ka: 1.54 × 104 L·mol-1, 298 K), while the accumulation of N-BCDs blocks the growth of profibrils in the elongation stage. To the best of our knowledge, it's the first time to observe the accumulation of N-BCDs around HI profibrils with TEM. Our study provides a new strategy for developing efficient nanoparticle inhibitors for protein fibrillation.

11.
Cardiovasc Diabetol ; 19(1): 10, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31969144

RESUMO

BACKGROUND: Although a variety of antidiabetic drugs have significant protective action on the cardiovascular system, it is still unclear which antidiabetic drugs can improve ventricular remodeling and fundamentally delay the process of heart failure. The purpose of this network meta-analysis is to compare the efficacy of sodium glucose cotransporter type 2 (SGLT-2) inhibitors, dipeptidyl peptidase-4 (DPP-4) inhibitors, glucagon-like peptide-1 (GLP-1) agonists, metformin (MET), sulfonylurea (SU) and thiazolidinediones (TZDs) in improving left ventricular (LV) remodeling in patients with type 2 diabetes (T2DM) and/or cardiovascular disease (CVD). METHODS: We searched articles published before October 18, 2019, regardless of language or data, in 4 electronic databases: PubMed, EMBASE, Cochrane Library and Web of Science. We included randomized controlled trials in this network meta-analysis, as well as a small number of cohort studies. The differences in the mean changes in left ventricular echocardiographic parameters between the treatment group and control group were evaluated. RESULTS: The difference in the mean change in LV ejection fraction (LVEF) between GLP-1 agonists and placebo in treatment effect was greater than zero (MD = 2.04% [0.64%, 3.43%]); similar results were observed for the difference in the mean change in LV end-diastolic diameter (LVEDD) between SGLT-2 inhibitors and placebo (MD = - 3.3 mm [5.31, - 5.29]), the difference in the mean change in LV end-systolic volume (LVESV) between GLP-1 agonists and placebo (MD = - 4.39 ml [- 8.09, - 0.7]); the difference in the mean change in E/e' between GLP-1 agonists and placebo (MD = - 1.05[- 1.78, - 0.32]); and the difference in the mean change in E/e' between SGLT-2 inhibitors and placebo (MD = - 1.91[- 3.39, - 0.43]). CONCLUSIONS: GLP-1 agonists are more significantly associated with improved LVEF, LVESV and E/e', SGLT-2 inhibitors are more significantly associated with improved LVEDD and E/e', and DPP-4 inhibitors are more strongly associated with a negative impact on LV end-diastolic volume (LVEDV) than are placebos. SGLT-2 inhibitors are superior to other drugs in pairwise comparisons.

12.
Thorac Cancer ; 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31994346

RESUMO

BACKGROUND: The development of biomarkers for the early detection of non-small cell lung cancer (NSCLC) is clinically important. We have developed miRNA biomarkers in sputum and plasma, respectively, for NSCLC. Herein, we evaluate whether integrated analysis of the miRNAs across the different types of specimens could improve the early detection of NSCLC. METHODS: Using reverse transcription PCR, we determined expressions of two miRNAs (miRs-31-5p and 210-3p) in sputum and three miRNAs (miRs-21-5p, 210-3p, and 486-5p) in plasma of a training cohort of 76 NSCLC patients and 72 cancer-free smokers. The results were validated in a testing cohort of 56 NSCLC patients and 55 cancer-free smokers. RESULTS: The panels of two sputum miRNAs and three plasma miRNAs had 65.8-75.0% sensitivities and 83.3-87.5% specificities for diagnosis of NSCLC in the training cohort. The individual sputum or plasma miRNA panel had a higher sensitivity for squamous cell carcinoma or adenocarcinoma of the lung, respectively. From the miRNAs, we optimized an integrated panel of biomarkers consisting of two sputum miRNAs (miRs-31-5p and 210-3p) and one plasma miRNA (miR-21-5p) that had higher sensitivity (85.5%) and specificity (91.7%) for diagnosis of NSCLC compared with the individual panels alone. Furthermore, the performance of the integrated panel of biomarkers was independent of histology and stage of NSCLC, and patients' age, sex, and ethnicity. The performance of the integrated panel of biomarkers was confirmed in the testing cohort. CONCLUSIONS: Integrating biomarkers across different body fluids would synergistically improve the early detection of NSCLC. KEY POINTS: Lung cancer is a heterogeneous disease and develops from complex aberrations. Integrating sputum and plasma miRNAs has higher accuracy than when they are used alone.

13.
Sex Transm Infect ; 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31911426

RESUMO

OBJECTIVES: Our objective was to determine the impact of maternal HIV-hepatitis B virus (HBV) coinfection on pregnancy outcomes. METHODS: The current study was conducted in a county of Yi Autonomous Prefecture in southwest China. Data were abstracted from hospitalisation records, including maternal and infant information. The seroprevalences of HIV and HBV infections and HIV-HBV coinfection were determined and the impact of maternal HIV-HBV coinfection on adverse pregnancy outcomes was assessed using logistic regression analysis. A treatment effects linear regression model was also applied to examine the effect of HBV, HIV or coinfection to quantify the absolute difference in birth weight from a reference of HBV-HIV negative participants. RESULTS: A total of 13 198 pregnant women were included in our study, and among them, 99.1% were Yi people and 90.8% lived in rural area. The seroprevalences of HIV and HBV infections and HIV-HBV coinfection were 3.6% (95% CI: 3.2% to 3.9%), 3.2% (95% CI: 2.9% to 3.5%) and 0.2% (95% CI: 0.1% to 0.2%) among the pregnant women, respectively. Maternal HIV-HBV coinfection was a risk factor for low birth weight (adjusted OR (aOR)=5.52, 95% CI: 1.97 to 15.40). Compared with the HIV mono-infection group, the risk of low birth weight was significantly higher in the HIV-HBV coinfection group (aOR=3.62, 95% CI: 1.24 to 10.56). Maternal HIV infection was associated with an increased risk of low birth weight (aOR=1.90, 95% CI: 1.38 to 2.60) and preterm delivery (aOR=2.84, 95% CI: 1.81 to 4.47). Perinatal death was more common when mothers were infected with HBV (aOR=2.85, 95% CI: 1.54 to 5.26). CONCLUSIONS: The prevalence of HIV infection was high among pregnant women of the Yi region. Both HIV and HBV infections might have adverse effects on pregnancy outcomes. Maternal HIV-HBV coinfection might be a risk factor for low birth weight in the Yi region, which needs to be confirmed.

14.
Mol Med Rep ; 21(2): 667-674, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31974596

RESUMO

The aim of the present study was to investigate whether class C1 decoy oligodeoxynucleotides (ODNs) can inhibit the expression of pro­fibrotic genes associated with rat hepatic stellate cell (HSC) activation and hepatic fibrosis. Luciferase reporter assays were performed to test the promoter activities of transforming growth factor (TGF)­ß and its downstream target genes following transfection of decoy ODNs and plasmids into HSC­T6 cells, and western blot assays were performed to measure the protein expression of those genes following decoy ODN transfection. Class C1 decoy ODNs were confirmed to inhibit the promoter activity of TGF­ß and its downstream target genes, such as type 1 collagen (COLI)α1, tissue inhibitor of metalloproteinases (TIMP)1 and α­smooth muscle actin by Gaussia luciferase reporter assay, and to further downregulate the expression of TGF­ß, SMAD3, COLIα1 and TIMP1 by western blotting in activated HSC­T6 cells. In conclusion, class C1 decoy ODNs inhibited pro­fibrotic gene expression in rat HSCS by downregulating TGF­ß signaling.

15.
J Neurosci Methods ; 333: 108576, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31923452

RESUMO

BACKGROUND: Classification of parkinsonian symptoms, including tremor and bradykinesia, require the application of validated clinical rating scales which are inherently subjective. In this study, we assessed an objective measure of parkinsonian symptomology using automated analysis of hand gestures. NEW METHOD: We constructed and evaluated a hand and finger motion capture apparatus and analysis pipeline that recorded hand/finger motion of control subjects and patients with Parkinson's disease. The detailed three-dimensional (3D) motion features of each finger joint was extracted by using Discrete Wavelet Transform (DWT). The severity of tremor for each finger joint was quantitated by analyzing the motion changes in the frequency domain on four types of motion from five patients and twenty-two control subjects. RESULTS: The proposed approach could distinguish the behavior of patients with Parkinson's disease and control subjects by analyzing the detailed motion features of their hands/fingers. COMPARISON WITH EXISTING METHODS: Previously established methods to quantitate finger movement dynamics focus on speed and amplitude. In contrast, our approach measures unsupervised motion features, in real-time, using wavelet analysis, of each individual finger joint during active free movement. CONCLUSIONS: The proposed study provides an objective assessment of tremor and bradykinesia in Parkinson's disease. Accordingly, this may help movement disorder clinicians to detect, diagnose and monitor treatment efficacy in Parkinson's disease.

16.
Sci Total Environ ; 704: 135335, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31784177

RESUMO

The population of wild musk deer (Moschus spp.) has declined in recent decades and reached an endangered status in China. Global climate change may drive the extinction rate of these species. To understand the implications of global warming on the future potential space utilization and migration direction of musk deer, both the maximum entropy model and barycenter migration analysis were utilized. Five global climate models and four representative concentration pathway scenarios were considered to simulate the distribution of six species for the years 2050 and 2070. The results indicated that the suitable habitat area would decrease over the next 30 to 50 years. These decreases of suitable habitat were more significant for the Siberian musk deer (reduced by 4.98% of the land area of China), the forest musk deer (1.04%), the black musk deer (0.86%), and the Himalayan musk deer (1.82%) compared with the other two musk deer species. The area with suitable climate for the Siberian musk deer will migrate to the southwest (to higher elevations) while areas suitable for the Alpine musk deer, the Himalayan musk deer, and the Anhui musk deer would all migrate to the northeast (to higher latitudes). However, the forest musk deer and the black musk deer will not migrate in the same direction, but will mainly migrate to the west and the north, respectively. These results provide data in support for in-situ conservation, ex-situ conservation, natural reserve community, and bio-corridor construction of China's musk deer species in response to global warming.

17.
Radiology ; 294(2): 245, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31769745
18.
Water Res ; 169: 115084, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31669906

RESUMO

Elemental sulfur-driven autotrophic denitrification (SADN) is a cost-effective approach for treating secondary effluent from wastewater treatment plants (WWTPs). Additional organics are generally supplemented to promote total nitrogen (TN) removal, reduce nitrite accumulation and sulfate production, and balance the pH decrease induced by SADN. However, understanding of the impacts of organic supplementation on microbial communities, nitrogen metabolism, denitrifier activity, and SADN rates in sulfur-based denitrification reactors is still limited. Here, a sulfur-based denitrification reactor was continuously operated for 272 days during which six different C/N ratios were tested successively (2.7, 1.5, 0.7, 0.5, 0.25, and 0). Organic supplementation improved TN removal and decreased NO2- accumulation, but reduced the relative abundance of denitrifiers and the contribution of autotrophic nitrate-reducing bacteria (aNRB) to TN removal during the long-term operation of reactor. Predictive functional profiling showed that nitrogen metabolism potential increased with decreasing C/N ratios. SADN was the predominant removal process when the C/N ratio was ≤0.7 (achieving 60% contribution when C/N = 0.7). Although organic supplementation weakened the dominant role of aNRB in denitrification, batch tests for the first time demonstrated that it could accelerate the SADN rate, attributed to the improvement of sulfur bioavailability, likely via the formation of polysulfide. A possible nitrogen removal pathway with multiple electron donors (i.e., sulfur, organics, sulfide, and polysulfide) in a sulfur-based denitrification reactor with organic supplementation was therefore proposed. However, supplementation with a high level of organics could increase the operational cost and effluent concentrations of sulfide and organics as well as enrich heterotrophic denitrifiers. Moreover, microbial community had substantial changes at C/N ratios of >0.5. Accordingly, an optimal C/N ratio of 0.25-0.5 was suggested, which could simultaneously minimize the additional operating cost associated with organic supplementation and maximize TN removal and SADN rates.


Assuntos
Reatores Biológicos , Desnitrificação , Processos Autotróficos , Suplementos Nutricionais , Nitratos , Nitrogênio , Enxofre
19.
J Cell Biochem ; 121(3): 2467-2477, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31736157

RESUMO

Matrine, also known as oxymatrine, is an important active ingredient of traditional Chinese herb Sophora flavescens. Recent studies have found that matrine may inhibit multiple tumors through inhibiting the tumor cell proliferation, inducing cell apoptosis, blocking cell cycle, suppressing cell invasion and migration and assisting in the synergy, and attenuation of radiotherapy and chemotherapy. This study mainly investigated the role of matrine in gastric cancer and its possible mechanism. The real-time fluorescence quantitative polymerase chain reaction technique showed that matrine inhibited the proliferation and migration of gastric tumor cells and significantly suppressed the expression of miR-93-5p. The dual-luciferase reporter gene assay indicated that AHNAK was a target gene of miR-93-5p and regulated by miR-93-5p and matrine. The torsion test demonstrated that matrine exerted its role via miR-93-5p while miR-93-5p played a role by targeting AHNAK. Thus, this study found that matrine affected the progression of gastric cancer by inhibiting the function of gastric cancer cells through the possible mechanism of inhibiting miR-93-5p expression to increase the expression level of the downstream target gene AHNAK.

20.
Transl Oncol ; 13(1): 25-31, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31743830

RESUMO

PURPOSE: In contrast to other studies, our previous study showed that adding induction chemotherapy (IC) to concurrent chemoradiotherapy (CCRT) significantly worsened the prognosis of patients with stage II nasopharyngeal carcinoma (NPC). However, the population used was small; therefore, there is an urgent need to confirm the result in a larger population because IC is still widely used in certain sections of china for stage II NPC. METHODS AND MATERIALS: We retrospectively analyzed an additional 272 patients. Therefore, in total, we report the results for 445 patients with stage II NPC treated with IC + CCRT or CCRT between June 2003 to June 2016 at the Zhejiang Cancer Hospital and Sun Yat-Sen University Cancer Center. RESULTS: This study included 445 patients treated with IC + CCRT (n = 195) or CCRT (n = 250). By last analysis, 22 (11.3%) patients in the IC + CCRT group developed local-regional recurrence and 23 (11.8%) patients developed distant metastases. Twenty-four (9.6%) patients in the CCRT group developed local-regional recurrence and 12 (4.8%) patients developed distant metastases. Univariate analyses showed that adding IC to CCRT significantly decreased the 5-year disease-free survival (DFS) (80.6% vs. 88.5%, P = .043); however, there was no statistically significant difference in 5-year overall survival (OS) (90.5% vs. 95.0%, P = .375). CONCLUSION: Using a larger population, the present study showed that adding IC to CCRT had a negative effect on patients with stage II NPC, which warrants further investigation.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA