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1.
Acta Pharmacol Sin ; 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32203081

RESUMO

Some studies have shown that gut microbiota along with its metabolites is closely associated with diabetic mellitus (DM). In this study we explored the relationship between gut microbiota and kidney injuries of early diabetic nephropathy (DN) and its underlying mechanisms. Male SD rats were intraperitoneally injected with streptozotocin to induce DM. DM rats were orally administered compound broad-spectrum antibiotics for 8 weeks. After the rats were sacrificed, their blood, urine, feces, and renal tissues were harvested for analyses. We found that compared with the control rats, DM rats had abnormal intestinal microflora, increased plasma acetate levels, increased proteinuria, thickened glomerular basement membrane, and podocyte foot process effacement in the kidneys. Furthermore, the protein levels of angiotensin II, angiotensin-converting enzyme, and angiotensin II type 1 receptor in the kidneys of DM rats were significantly increased. Administration of broad-spectrum antibiotics in DM rats not only completely killed most intestinal microflora, but also significantly lowered the plasma acetate levels, inhibited intrarenal RAS activation, and attenuated kidney damage. Finally, we showed that plasma acetate levels were positively correlated with intrarenal angiotensin II protein expression (r = 0.969, P < 0.001). In conclusion, excessive acetate produced by disturbed gut microbiota might be involved in the kidney injuries of early DN through activating intrarenal RAS.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32182035

RESUMO

A safe and efficient delivery system is critical for clinical application of siRNA. However, the conventional electrostatic interaction-based siRNA nanoplexes with bulk mixing preparation were always unsatisfactory for its stability and safety. In this study, the new core-shell lipid/PCL-PEI/siRNA nanoparticles (LPS NPs) endowing holonomic constraint of siRNA in the inner core were prepared by microfluidic technology. On the microfluidic chip, siRNAs were completely compressed into the inner hydrophilic core of reverse PCL-PEI micelles at a low N/P ratio of 5, followed by coating a neutral lipid membrane to form core-shell nanoparticles, which had a uniform size (120.2 ± 1.4 nm) and a negative charge (-8.8 ± 1.6 mV). Compared to bulk mixing-based LMS NPs, the lower usage of cationic PCL-PEI materials and stronger protection of siRNA in serum were found in the microfluidic-based LPS NPs. Furthermore, it was demonstrated that the LPS NPs exhibited significant downregulation of EGFR mRNA and protein expression level both in vitro and in vivo, and showed significant inhibition of tumor growth following systemic administration along with no obvious systemic toxicity. These findings demonstrated that the microfluidic-based lipid/polymer hybrid nanoassemblies would offer a promising siRNA delivery system for clinical application.

3.
Oncol Lett ; 19(4): 3358, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32218871

RESUMO

[This corrects the article DOI: 10.3892/ol.2014.2123.].

4.
Int J Neurosci ; : 1-12, 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32125198

RESUMO

Cerebral ischemic stroke, caused by obstruction of the blood flow to the brain, initiates a complex cascade of pathophysiological changes. The aim of the present study was to assess the protective role and the underlying mechanism of troxerutin and cerebroprotein hydrolysate (TCH) injections for five days in rats subjected to middle cerebral artery occlusion (MCAO). Male Sprague-Dawley rats treated with either TCH or a vehicle (0.9% saline) via intraperitoneal injection were examined one or three days after MCAO. TCH alleviated neurological deficits and reduced infarct volume, innate immune response, blood-brain barrier destruction, and suppressed cell apoptosis. The therapeutic effects of TCH were achieved by diminished neuronal nitric oxide synthase (nNOS) and inducible nitric oxide synthase (iNOS), and increased endothelial nitric oxide synthase (eNOS). Furthermore, L-NAME showed an inhibitory effect against TCH after MCAO on eNOS expression, NO and peroxynitrite production, neurobehavioral score, and infarct volume. The results indicate that injection of TCH has multifaceted neuroprotective effects against MCAO via regulation of the various NOS isoforms.

5.
Ecotoxicol Environ Saf ; 194: 110343, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32151862

RESUMO

For the treatment of low C/N wastewaters, methanol or acetate is usually dosed as electron donor for denitrification but such organics makes the process costly. To decrease the cost, iron which is the fourth most abundant element in lithosphere is suggested as the substitution of methanol and acetate. The peak volumetric removal rate (VRR) of nitrate nitrogen in the ferrous iron-dependent nitrate removal (FeNiR) reactor was 0.70 ± 0.04 kg-N/(m3·d), and the corresponding removal efficiency was 98%. Iron showed toxicity to cells by decreasing the live cell amount (dropped 56%) and the live cell activity (dropped 70%). The toxicity of iron was mainly expressed by the formation of iron encrustation. From microbial community data analysis, heterotrophs (Paracocccus, Thauera and Azoarcus) faded away while the facultative chemolithotrophs (Hyphomicrobium and Anaerolineaceae_uncultured) dominated in the reactor after replacing acetate with ferrous iron in the influent. Through scanning electron microscope (SEM) and transmission electron microscope (TEM), two iron oxidation sites in FeNiR cells were observed and accordingly two FeNiR mechanisms were proposed: 1) extracellular FeNiR in which ferrous iron was bio-oxidized extracellularly; and 2) intracellular FeNiR in which ferrous iron was chemically oxidized in periplasm. Bio-oxidation (extracellular FeNiR) and chemical oxidation (intracellular FeNiR) of ferrous iron coexisted in FeNiR reactor, but the former one predominated. Comparing with the control group without electron donor in the influent, FeNiR reactor showed 2 times higher and stable nitrate removal rate, suggesting iron could be used as electron donor for denitrification. However, further research works are still needed for the practical application of FeNiR in wastewater treatment.

6.
Artigo em Inglês | MEDLINE | ID: mdl-32162743

RESUMO

AIMS: His-Purkinje system pacing has been demonstrated as a synchronized ventricular pacing strategy via pacing His-Purkinje system directly, which can decrease the incidence of adverse cardiac structure alteration compared with right ventricular pacing (RVP). The purpose of this meta-analysis was to compare the effects of His-Purkinje system pacing and RVP in patients with bradycardia and cardiac conduction dysfunction. METHODS: PubMed, Embase, Cochrane Library, and Web of Science were systematically searched from the establishment of databases up to 15 December 2019. Studies on long-term clinical outcomes of His-Purkinje system pacing and RVP were included. Chronic paced QRS duration, chronic pacing threshold, left ventricular ejection fraction (LVEF), left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), all-cause mortality, and heart failure hospitalization were collected for meta-analysis. RESULTS: A total of 13 studies comprising 2348 patients were included in this meta-analysis. Compared with RVP group, patients receiving His-Purkinje system pacing showed improvement of LVEF (mean difference [MD], 5.65; 95% confidence interval [CI], 4.38-6.92), shorter chronic paced QRS duration (MD, - 39.29; 95% CI, - 41.90 to - 36.68), higher pacing threshold (MD, 0.8; 95% CI, 0.71-0.89) and lower risk of heart failure hospitalization (odds ratio [OR], 0.65; 95% CI, 0.44-0.96) during the follow-up. However, no statistical difference existed in LVEDV, LVESV and all-cause mortality between the two groups. CONCLUSION: Our meta-analysis suggests that His-bundle pacing is more suitable for the treatment of patients with bradycardia and cardiac conduction dysfunction.

7.
Phys Rev Lett ; 124(6): 067202, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32109129

RESUMO

Understanding many-body physics of elementary excitations has advanced our control over material properties. Here, we study spin-flip excitations in NiO using Ni L_{3}-edge resonant inelastic x-ray scattering (RIXS) and present a strikingly different resonant energy behavior between single and double spin-flip excitations. Comparing our results with single-site full-multiplet ligand field theory calculations we find that the spectral weight of the double-magnon excitations originates primarily from the double spin-flip transition of the quadrupolar RIXS process within a single magnetic site. Quadrupolar spin-flip processes are among the least studied excitations, despite being important for multiferroic or spin-nematic materials due to their difficult detection. We identify intermediate state multiplets and intra-atomic core-valence exchange interactions as the key many-body factors determining the fate of such excitations. RIXS resonant energy dependence can act as a convincing proof of existence of nondipolar higher-ranked magnetic orders in systems for which, only theoretical predictions are available.

8.
Medicine (Baltimore) ; 99(5): e18917, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32000400

RESUMO

BACKGROUND: B-type Raf kinase (BRAF) mutation is proved to be a critical predictive factor in papillary thyroid cancer (PTC) with aggressive characteristics. However, the association between BRAF mutation and cervical lymphatic metastasis in PTC is controversial. METHODS: We searched papers on the study of BRAF mutation and cervical lymphatic metastasis in PTC patients through PubMed, Web of Science, Embase, and Cochranelibrary. The BRAF (+) cases, BRAF (-) cases, and cervical lymphphatic metastatic cases in both BRAF (+) and BRAF (-) groups were collected. After Quality assessment, statistical Analysis (funnel plot and Harbord evaluation, Random-effect model, heterogeneity, subgroup analysis, sensitivity analysis, and metacum analysis) were done by the Review Manager (RevMan) 5.3 and stata14 statistical software. RESULTS: There were 78 cross-section studies which met our inclusion criteria. And all of them had no selection bias, publication bias, or any other bias. A significant association existed between BRAF mutation and cervical lymph node metastasis (LNM) (odds ratio [OR] = 1.63; 95% confidence interval [CI]: 1.44-1.84; P < .05). Overall, 46 studies were conducted among East Asians. Twenty four articles had provided the data of central lymph node metastasis (CLNM), 11 articles with the data of lateral lymph node metastasis (LLNM), and classic/conventional PTC (CPTC) was analyzed in 10 studies. Subgroup analyses were performed based on ethnicity, metastatic site, and subtype of PTC. Significant association between BRAF (+) mutation and cervical LNM were indicated in East Asians (OR = 1.73; 95% CI: 1.49-2.02; P < .05), in non-East Asians (OR = 1.57; 95% CI: 1.26-1.96; P < .05), and in CLNM (OR = 1.80; 95% CI: 1.56-2.07; P < .05). While no significant association was found in LLNM (OR = 1.37; 95% CI: 0.76-2.48; P = .29 > .05) and in CPTC (OR = 1.32; 95% CI: 0.97-1.80; P = .08 > .05). We did not find any other major changes when sensitivity analysis was performed. The metacum analysis showed no significant association existed before 2012. While a significant association began to exist between BRAF mutation and LNM from 2012, and this association became stable from 2017. CONCLUSIONS: We consider that a significant association exists between BRAF mutation and cervical LNM. Further meta-analysis on subgroup may reveal some valuable factors between BRAF gene mutation and LNM. And we do not recommend that BRAF (+) as the biomarker for LNM in PTC.


Assuntos
Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/genética , Quinases raf/genética , Humanos , Metástase Linfática , Pescoço/patologia , Câncer Papilífero da Tireoide/patologia
9.
Phytochemistry ; 172: 112281, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32044582

RESUMO

Ten undescribed highly oxidized sesquiterpenes and six known sesquiterpenes were isolated from H2O-soluble part of the fruits of Illicium lanceolatum A. C. Smith. The structures of undescribed compounds were elucidated by interpretation of spectroscopic data, and the absolute configurations of 2α-hydroxyneoanisatinic acid, (1R,5R,6S,7R,9R,10R)-3,4-dehydro-12-hydroxy-floridanolide, and (1R,4S,5R,6S,7S,9S)-1-deoxy-13-hydroxymerrilactone B were determined by the single-crystal X-ray diffraction analysis. Illilanceolatin A was the first example of a seco-prezizaane type sesquiterpene with a hemiacetal moiety located at C-10. 2α-Hydroxyneoanisatinic acid and anisatinic acid were two naturally occurring undescribed seco-prezizaane type sesquiterpenes with a 5/5/6 tricyclic carbon skeleton. Plausible biosynthetic pathways of the isolated polycyclic and highly oxidized sesquiterpenes derived from the intermediate allo-cedrane were proposed. (1R,5R,6S,7R,9R,10R)-3,4-dehydro-12-hydroxy-floridanolide, 1,3-dihydroxyneoanisatin, and 2α-hydroxyneoanisatin displayed neuroprotective effects with protection rates of 19.9, 22.7 and 24.3% at 10 µM, respectively. Additionally, the preliminary acute toxicity of anisatinic acid was also evaluated.


Assuntos
Illicium , Fármacos Neuroprotetores , Sesquiterpenos , Cristalografia por Raios X , Frutas , Estrutura Molecular
10.
Artigo em Inglês | MEDLINE | ID: mdl-32011783

RESUMO

To gain insight into the underlying mechanisms of catalyst durability for the selective catalytic reduction (SCR) of NOx with an ammonia reductant, we employed scanning transmission X-ray microscopy (STXM) to study Cu-exchanged zeolites with the CHA and MFI framework structures before and after simulated 135 000-mile aging. X-ray absorption near-edge structure (XANES) measurements were performed at the Al K- and Cu L-edges. The local environment of framework Al, the oxidation state of Cu, and geometric changes were analyzed, showing a multi-factor-induced catalytic deactivation. In Cu-exchanged MFI, a transformation of CuII to CuI and Cux Oy was observed. We also found a spatial correlation between extra-framework Al and deactivated Cu species near the surface of the zeolite as well as a weak positive correlation between the amount of CuI and tri-coordinated Al. By inspecting both Al and Cu in fresh and aged Cu-exchanged zeolites, we conclude that the importance of the preservation of isolated CuII sites trumps that of Brønsted acid sites for NH3 -SCR activity.

11.
Dis Esophagus ; 33(2)2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31942617

RESUMO

Diabetes mellitus (DM) is one of the most common comorbidities in esophageal cancer patients who undergo esophagectomy. It is well established that DM has an unfavorable impact on short-term outcomes of patients with surgically treated esophageal cancer; however, whether DM has any impact on long-term survival of these patients remains unclear. We performed the first meta-analysis to investigate the impact of DM on survival of surgically treated esophageal cancer patients. We searched the following databases systematically to retrieve relevant studies on January 2, 2019: PubMed, Embase, and Web of Science. The main outcome data consisting of 3- and 5-year overall survival (OS) rates and hazard ratios (HRs) of OS were extracted to compare survival between patients with and without DM. We finally included for meta-analysis a total of eight cohort studies involving 5,044 esophageal cancer patients who underwent esophagectomy. We found no significant difference between 3-year (risk ratio [RR] = 0.94, 95% CI: 0.73-1.21; P = 0.65) and 5-year (RR = 0.92, 95% CI: 0.80-1.08; P = 0.31) OS rates between patients with and without DM after esophagectomy. Moreover, DM was not found to be an independent predictor of OS for these patients (HR = 1.10, 95% CI: 0.65-1.84; P = 0.72). Our study suggests that DM appears to have no significant impact on long-term survival of esophageal cancer patients who undergo esophagectomy. To improve the prognosis of these patients, it may be more important to control glycemic level in patients with DM who undergo esophagectomy. However, further high-quality studies with appropriate adjustment for confounding factors are needed to verify this conclusion.

12.
J Pharm Biomed Anal ; 181: 113106, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-31962248

RESUMO

A rapid and reproducible method with high selectivity was developed for simultaneous determination of a promising anti-brain tumor agent CAT3 and its two metabolites PF403 and GLU-PF403 in mouse plasma and brain. An economic deproteinization with septuple acetonitrile (v/v) was applied to pretreat the samples in this study. All analytes were well retained and separated on a CAPCELL CORE PC (2.7 µm, 2.1 mm I.D. × 150 mm, SHISEIDO Technologies) column with an eluting solvent of acetonitrile /water containing 0.1 % formic acid (v/v) at the flow rate of 0.2 mL per minute. The detection was carried out on a Q Exactive high resolution mass spectrometer equipped with a HESI ion source in parallel reaction monitoring (PRM) mode. The corresponding transitions for quantitation were 434.23→ 70.07 for CAT3, 350.17→70.07 for PF403, 526.21→70.07 for GLU-PF403, 364.19→70.07 for IS-1 and 625.18→317.07 for IS-2, respectively. A well-linear fit curve was achieved among the range of 0.1∼50 ng/mL for CAT3, 0.2∼100 ng/mL for PF403 and 2.5∼600 ng/mL for GLU-PF403 both in mouse plasma and brain homogenate. The intra-/inter-day accuracies of three analytes were within ±14.5 % and precisions were below to 13.44 %. The mean values of recovery of three compounds in mouse plasma and brain homogenate were among 98.06 ∼ 118.63 % and 81.04∼108.69 %. The analytes in NaF-treated ice cold blood of mouse was stable within tested 30 min. Plasma and brain homogenate samples had no obvious changes during all storage, sample treatment and analytic process of mouse plasma sample. The reproducible and reliable method was well employed to the research of CAT3 pharmacokinetic characteristics in mouse plasma and brain after a single intragastric administration at dose of 10 mg/kg.

13.
Glycoconj J ; 37(2): 139-149, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31974821

RESUMO

The O antigen is indispensable for the full function and virulence of pathogenic bacteria. During O-repeating unit (RU) biosynthesis, committed glycosyltransferases (GTs) transfer various sugars from an activated sugar donor to the appropriate lipid carrier sequentially. While the nucleotide sequence specific for O antigen of pathogenic bacteria is already known, the exact substrate specificity of most hypothetical GTs have yet be characterized. In the present paper, we report the biochemical characterization of one alpha-glucosyltransferase, WfgE, a member of GT family 4. This enzyme is implicated in the pentasaccharide RU biosynthetic pathway of E. coli O152 O antigen. A chemoenzymatically synthesized acceptor (GlcGlcNAc α-PP-O(CH2)10CH3) was used to characterize the WfgE activity. The enzyme product was determined to have a 1,2-linkage using strategy based on collision-induced dissociation electrospray ionization ion trap multiple tandem MS (CID-ESI-IT-MSn). The lack of a DxD motif and its high activity without divalent metal ions suggests that WfgE belongs to the GT-B fold superfamily. The enzyme is specific for beta-glucose or galactose-terminating acceptor substrates, and in particular UDP-glucose but also UDP-galactose as donor substrates. Our results suggest that WfgE catalyses the addition of the third sugar residue of the E. coli O152 O-RU. The recombinant GST-WfgE was solubilized and further purified to homogeneity via GST affinity chromatography, paving the way for structure-function relationship studies.

14.
J Vasc Res ; 57(1): 24-33, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31715615

RESUMO

AIM: Glucose fluctuations may be responsible for, or further the onset of arterial hypertension, but the exact mechanisms remain unclear. The purpose of this study was to investigate the mechanisms behind and related to aortic fibrosis and aortic stiffening induced by glucose fluctuations. METHODS: Sprague-Dawley rats were injected with streptozotocin (STZ) and randomly divided into three treatment groups: controlled STZ-induced diabetes (C-STZ); uncontrolled STZ-induced diabetes (U-STZ); and STZ-induced diabetes with glucose fluctuations (STZ-GF). After 3 weeks, rat blood pressure (BP) was tested, and aortic fibrosis was detected by using the Masson trichrome staining technique. Levels of p38 mitogen-activated protein kinase (p38 MAPK), runt-related transcription factor 2 (Runx2), collagen type 1 (collagen I), and NADPH oxidases were determined by Western blot.Rat vascular smooth muscle cells in vitro were used to explore underlying mechanisms. RESULTS: The systolic BP of diabetic rats in the C-STZ, U-STZ, and STZ-GF groups was 127.67 ± 6.53, 150.03 ± 5.24, and 171.63 ± 3.53 mm Hg, respectively (p< 0.05). The mean BP of diabetic rats in the three groups was 91.20 ± 10.07, 117.29 ± 4.28, and 140.58 ± 2.14 mm Hg, respectively (p< 0.05). The diastolic BP of diabetic rats in the three groups was 73.20 ± 12.63, 101.93 ± 5.79, and 125.37 ± 4.62 mm Hg, respectively (p< 0.05). The ratios of fibrosis areas in the aortas of the three groups were 11.85 ± 1.23, 29.00 ± 0.87, and 48.36 ± 0.55, respectively (p< 0.05). The expressions of p38 MAPK, Runx2, and collagen I were significantly increased in the STZ-GF group. In vitro, applications of inhibitors of reactive oxygen species (ROS) and p38 MAPK successfully reversed glucose fluctuations that would have possibly induced aortic fibrosis. CONCLUSIONS: Blood glucose fluctuations aggravate aortic fibrosis via affecting the ROS/p38 MAPK /Runx2 signaling pathway.

15.
Bioresour Technol ; 297: 122426, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31776106

RESUMO

Nitrite has a key role in nitrogen conversion during composting. In this study, the dynamic changes in the NO2- contents, abundances of nirS and nxrA, and the bacteria that harbored these genes were determined during composting. NO2- accumulated during the initial composting stage. The nirS gene was abundant throughout composting, whereas the nxrA gene was only abundant in the late composting phases. Ralstonia sp. and Thauera sp. were the dominant denitrifiers that harbored nirS, and Nitrobacter winogradskyi Nb-255 was the dominant nitrifier that harbored nxrA. Structural equation modeling showed that NO2- was mainly reduced by nirS in the early phases, and oxidized by nxrA in the late phases, but especially in the maturity phase. Network analysis showed that the dominant bacteria harboring nirS and nxrA were hubs in the modules related to the reduction and oxidation of NO2-, and they had competitive relationships during the cooling and maturity phases.


Assuntos
Compostagem , Nitrobacter , Animais , Bactérias , Esterco , Nitritos , Suínos
16.
Ann Surg Oncol ; 27(2): 472-480, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31617120

RESUMO

OBJECTIVE: We investigated the possible lobe-specific lymph node (LN) metastasis pattern of early-stage peripheral non-small cell lung cancers (NSCLC) and define the extent of lobe-specific LN dissection for them. METHODS: We retrospectively collected clinical data of patients undergoing lobectomy or segmentectomy with systematic lymphadenectomy for clinical T1N0M0 peripheral NSCLC from January 2015 to December 2018. The LN metastasis pattern was analyzed by tumor lobe location. RESULTS: A total of 590 patients were included for analysis. The mean number of total dissected LNs was 12.3 ± 5.8 and 8.2 ± 4.1 for total dissected mediastinal LNs. The rate of mediastinal LN metastasis was 9.5%. For cases of upper lobe tumor and lower lobe tumor, 8.8% and 6.0% of them respectively metastasized to the upper LN zone (P = 0.274). However, upper lobe tumors hardly metastasized to the subcarinal (0.3%) and lower (0.3%) LN zones while for lower lobe tumors, the rate of LN metastasis was 10.2% and 5.4% respectively (both P < 0.001). However, all cases (100%) metastasizing from lower lobes to the upper LN zone had a tumor size of 2-3 cm, whereas cases with a tumor size ≤ 2 cm had no metastasis (0%). None of the tumors in the right middle lobe metastasized to the lower LN zone (0%). CONCLUSIONS: A lobe-specific LN metastasis pattern was observed in clinical stage IA peripheral NSCLC. For tumors in upper lobes (≤ 3 cm), there may be no need to dissect lower mediastinal LNs and for tumors in lower lobes (≤ 2 cm), dissecting upper mediastinal LNs may not be required.

17.
Nanoscale ; 12(1): 316-325, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31825048

RESUMO

Micro-/nanostructured silicon (Si) photoelectrodes are promising for efficient solar-driven water splitting. In this work, an elaborate study on textured Si photocathodes is reported. Compared to conventional textured Si photocathodes, the well-designed Si photocathode with randomly-distributed inverted pyramid arrays (SiIPs) generates a larger photovoltage of 440 mV for its higher effective minority carrier density, and produces a higher photocurrent density at a high reverse bias voltage due to its quasi-hydrophilicity. With the help of cobalt disulfide (CoS2) nanocrystals, sluggish charge kinetics of SiIP photocathodes can be further improved. The optimal SiIP/CoS2 photocathode yields an onset potential of 0.22 V vs. reversible hydrogen electrode (RHE) and a saturated photocurrent density of 10.4 mA cm-2 at -0.45 V (vs. RHE). Besides, this cathode produces a stable photocurrent density of ∼6.60 mA cm-2 at 0 V (vs. RHE) for 12 000 s in acidic media. Notably, our work presents a facile and inexpensive method to fabricate efficient Si photoelectrodes, which may promote the evolution of textured Si-based electrodes for potential photoelectrochemical and photocatalytic applications.

18.
Neurol Sci ; 41(1): 83-90, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31440863

RESUMO

Diabetes mellitus (DM) and neurosyphilis (NS) may both damage the blood-brain barrier (BBB). It seems that non-neurosyphilis (non-NS) patients with high HbA1c levels are likely to develop into NS. However, the correlation of HbA1c level with BBB disruption in syphilis (non-NS) patients is unclear. In this study, we used dynamic contrast-enhanced (DCE) MRI to quantify regional BBB permeability in syphilis (non-NS) patients and detected several molecular biomarkers of cerebrospinal fluid (CSF). We found that BBB permeability values in the hippocampus, white matter, and cortex inferior temporal gyrus were correlated with albumin quotient (Qalb), CSF concentrations of interleukin IL-6 and IL-10. Moreover, BBB breakdown in white matter was correlated with CSF concentrations of sICAM-1 and sVCAM-1. In conclusion, our data suggest that BBB integrity may be liable to be disrupted in syphilis (non-NS) patients, patients with high HbA1c levels, as well as syphilis (non-NS) patients with high HbA1c levels, and it is particularly important to control blood glucose in these patients.

19.
Neuroscience ; 425: 169-180, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31794821

RESUMO

The causal connections among small-scale regions based on resting-state fMRI data have been extensively studied and a lot of achievements have been demonstrated. However, the causal connection among large-scale regions was seldom discussed. In this paper, we applied global Granger causality analysis to construct the causal connections in the whole-brain network among 103 healthy subjects (33 M/66F, ages 20-23) based on a resting-state fMRI dataset. We further explored four large-scale cognitive networks which have been widely known: central executive network (CEN), default mode network (DMN), dorsal attention network (DAN) and salience network (SN). These four cognitive networks are particularly important for understanding higher cognitive functions and dysfunction. Based on the above research, Out-In degree were introduced to identify the driving and driven hubs. Studying the driving and driven hub of brain network is of great significance for assessing the functional mechanism of the brain network. There were 817 directed edges identified as significant among the 8010 possible causal connections; seven driving hubs and ten driven hubs were identified in the whole-brain network. In CEN, dorsolateral prefrontal cortex (DlPFC) and superior parietal cortex (SPC) were the driven and driving hubs, respectively; in DMN, they were posterior cingulate cortex (PCC) and medial prefrontal cortex (MPFC); in DAN, they were frontal eye fields (FEF) and intraparietal sulcus (IPS); and in SN, they were frontoinsular cortex (FIC) and medial frontal cortex (MFC). These findings may provide insights into our understanding of human brain function mechanisms and the diagnosis of brain diseases.

20.
Anticancer Drugs ; 31(2): 123-130, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31815763

RESUMO

Cisplatin (CDDP) is the most effective chemotherapeutic drug against lung carcinoma. However, the emergence of resistant clones has severely limited its clinical application. We found that the cisplatin-resistant lung carcinoma cell line A549/CDDP had increased levels of the phosphorylated gap junction protein Cx43 and SRC tyrosine kinase, and low levels of total Cx43 protein and reduced gap junction formation. The SRC kinase inhibitor PP2 increased the expression of total Cx43 protein and enhanced cisplatin sensitivity, indicating that activated SRC kinase induces chemoresistance by decrease total Cx43 level. Furthermore, Cx43 gene silencing in the drug-resistant cell lines abrogated the sensitizing effect of PP2. Taken together, targeting SRC kinase by PP2 reverses cisplatin resistance by upregulating Cx43 protein levels, indicating a novel pathway of cisplatin resistance that may be amenable to therapeutic intervention.

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