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1.
Biosci Rep ; 41(4)2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33835138

RESUMO

OBJECTIVE: The present study aimed to identify risk factors for overall survival in advanced hepatocellular carcinoma (HCC) patients and establish a scoring system to select patients who would benefit from hepatic resection. METHODS: Survival curves were analyzed using the Kaplan-Meier method and log-rank test. The prognostic scoring system was developed from training cohort using a Cox-regression model and validated in a external validation cohort Results: There were 401 patients in the training cohort, 163 patients in the external validation cohorts. The training cohort median survival in all patients was 12 ± 1.07 months, rate of overall survival was 49.6% at 1 year, 25.0% at 3 years, and 18.0% at 5 years. A prognostic scoring system was established based on age, body mass index, alkaline phosphatase, tumor number and tumor capsule. Patients were classified as low- risk group(≤3.5) or high-risk group(>3.5). High-risk patients had a median survival of 9 months, compared with 23 months in low-risk patients. The area under the receiver operating characteristic curve (AUC) of the prognostic scoring system was 0.747 (0.694-0.801), which is significantly better than AFP, Child-Pugh and ALBI. The AUC of validation cohorts was 0.716 (0.63-0.803). CONCLUSION: A prognostic scoring system for hepatic resection in advanced HCC patients has been developed based entirely on preoperative variables. Patients classified as low risk using this system may experience better prognosis after hepatic resection.

2.
Curr Med Chem ; 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33874866

RESUMO

Considerable evidence has proved that disturbed cholesterol metabolism played a crucial role in diabetic kidney disease. Besides, massive cholesterol depositions were found in intrinsic renal cells of diabetic kidney disease patients and animal models, causing cytotoxicity, and affecting renal function. Statins could alleviate cholesterol depositions, podocyte injury and microalbuminuria of diabetic kidney disease. In the review, we summarized the process of disturbed cholesterol metabolism and discussed how it induced kidney dysfunction in diabetic kidney disease.

3.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(2): 535-539, 2021 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-33812427

RESUMO

OBJECTIVE: To assess the impact of early relapse (ER) after autologous hematopoietic stem cell transplan-tation (AHSCT) on overall survival (OS) for multiple myeloma (MM) patients. METHODS: Clinical data of 37 patients with MM undergoing AHSCT in department of hematology of Shanxi Bethune Hospital from January 2012 to December 2017 were retrospectively analyzed. The effect of ER on OS of patients was analyzed. The effects of international staging system (ISS) staging, cytogenetics, pre-transplant efficacy, minimal residual disease, and age on OS of the patients were also analyzed respectively. RESULTS: Among the 37 patients, 13 cases (35.1%) had ER, and 24 cases (64.9%) had non-ER. 3 patients with ER had extramedullary disease, but none with non-ER showed extramedullary disease. More than or equal to very good partial rate (VGPR) in patients with ER and without ER were 3 cases (23.1%) and 15 cases (62.5%), respectively, and the curative effect of the former was significantly lower than that of the latter (P<0.05). The median follow-up time was 31 (12-96) months, and median OS time was 93 months in all the patients. The median survival time of patients with ER was 17 months, and the median progression free survival was 7 months, both were significantly shorter than 93 months and 38 months of patients with non-ER (P<0.05). Univariate analysis showed that the OS was affected by ER, cytogenetic abnormalities (FISH), and ≥VGPR before transplantation. Multivariate analysis showed that ER was an independent prognostic factor. CONCLUSION: The prognosis of patients with ER after AHSCT in newly diagnosed MM is poor. ER is an independent prognostic factor of survival.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Mieloma Múltiplo , Humanos , Prognóstico , Recidiva , Estudos Retrospectivos , Transplante Autólogo , Resultado do Tratamento
4.
J Mater Chem B ; 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33908594

RESUMO

Plasma membrane (PM), a fundamental building component of a cell, is responsible for a variety of cell functions and biological processes. However, it is still challenging to acquire its morphology and morphological variation information via an effective approach. Herein, we report a PM imaging study regarding an aggregation-induced emission luminogen (AIEgen) called tetraphenylethylene-naphthalimide+ (TPE-NIM+), which is derived from our previously reported tetraphenylethylene-naphthalimide (TPE-NIM). The designed AIEgen (TPE-NIM+) shows significant characteristics of ultrafast staining, high photostability, wash-free property, and long retention time at the PM, which can structurally be correlated with its positively charged quaternary amine and hydrophobic moiety. TPE-NIM+ is further applied for staining of different cell lines, proving its universal PM imaging capability. Most importantly, we demonstrate that TPE-NIM+ can clearly delineate the contours of densely packed living cells with high cytocompatibility. Therefore, TPE-NIM+ as a PM imaging reagent superior to currently available commercial PM dyes shall find a number of applications in the biological/biomedical fields and even beyond.

5.
Nanotechnology ; 2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33887710

RESUMO

Transforming levulinic acid (LA) to γ-valerolactone (GVL) is a significant route for converting biomass into valuable chemicals. The development of an efficient and robust heterogeneous catalyst for this reaction has aroused great interest. In this work, nitrogen-doped graphene (NG) supported nickel (Ni) based heterogeneous catalyst with excellent activities was successfully synthesized. The Ni/NG catalyst shows outstanding performance for hydrogenation of LA to GVL at a relatively low temperature of 140 °C, which is superior then most of the present reported heterogeneous catalyst. Further investigation indicated the Ni nanoparticles were the active sites and the NG also plays an indispensable role. The catalytic performance was highly depended on the crystallinity, particles sizes and electronic structure of Ni in Ni/NG catalyst, which can be optimized by nitrogen doping. This work affords a new route for designing robust and excellent heterogeneous catalysts by doping method to optimize the support.

6.
Mikrochim Acta ; 188(5): 165, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33856578

RESUMO

The construction of multifunctional sensors has attracted considerable attention due to their multifunctional properties, such as high sensitivity and rapid detection. Herein, near-infrared multifunctional fluorescent sensing materials based on core-shell upconversion nanoparticle@magnetic nanoparticle and molecularly imprinted polymers were synthesized for rapid detection of deltamethrin. The difunctional core-shell upconversion nanoparticle@magnetic nanoparticle was introduced as the optical signal and rapid separator. Firstly, the difunctional core-shell materials were prepared through solvothermal method. Then, molecularly imprinted polymers (MIPs) as recognition elements for deltamethrin were coated on the surface of upconversion nanoparticle@magnetic nanoparticle through polymerization. The structure and recognition characterizations of multifunctional fluorescent sensing materials were evaluated. Under optimal condition, the imprinting factor of sensing materials was 3.63, and the fluorescence intensity of sensing materials decreased linearly with increasing concentration of deltamethrin from 0.001 to 1 mg L-1 with a detection limit of 0.749 µg L-1, and a relative standard deviation of 3.10% was obtained with 5 mg L-1 deltamethrin. The sensing materials showed a high selectivity and were successfully utilized for the detection of deltamethrin in grapes and cabbages; the results showed that the recoveries for two samples obtained were 95.6-102% and 91.8-105%.

7.
Inorg Chem ; 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33929182

RESUMO

By the reaction of inorganic-ligand CdS/Cd2+ quantum dots (QDs) with inorganic-ligand CdSe/CdS/S2- nanoplatelets (NPLs), semiconductor CdS QDs were fused with CdSe/CdS NPLs to yield all-inorganic assemblies, accompanied by great photoluminescence-enhancement. These all-inorganic assemblies facilitate charge transport between each other and open up interesting prospects with electronic and optoelectronic nanodevices.

9.
J Cardiothorac Surg ; 16(1): 101, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33882974

RESUMO

BACKGROUND: Many patients with mitral regurgitation are denied open-heart surgery due to perceived high risk. Transcatheter mitral valve replacement is a therapeutic alternative for patients at high surgical risk. This study aimed to assess the feasibility of a new self-expanding valved stent for transcatheter mitral valve replacement via apex in an acute animal model. METHODS: Eight porcine experiments were performed in the acute study. A left thoracotomy was performed, and the new self-expanding transcatheter valved stent was deployed under fluoroscopic guidance in the native mitral annulus via apex. Hemodynamic data were recorded before and after implantation. Mitral annulus diameter and valve area were measured using echocardiography. Transvalvular and left ventricular outflow tract pressure gradients were measured using invasive methods. RESULTS: Seven animals underwent successful transapical mitral valve replacement; the implantation was unsuccessful in one animal. The mean procedure time, defined from placement to tightening of the purse-string suture, was 17.14 ± 7.86 min. Hemodynamic data before and after transapical mitral valve replacement showed no difference in statistical analysis. The mean diameter of the self-expanding device after implantation was 2.58 ± 1.04 cm; the mean functional area was 2.70 ± 0.26 cm2. Trace-to-mild central and paravalvular leaks were detected in 7 valves. The mean pressure gradient across the self-expanding device was 2.00 ± 0.82 mmHg; the corresponding gradient across the LVOT was 3.28 ± 1.11 mmHg. Postmortem evaluation confirmed precise device positioning in 7 animals with no signs of LVOT obstruction. CONCLUSION: Transcatheter mitral replacement of the new valved stent was confirmed feasible in acute preclinical models. The new stent reveals optimal design parameters.

10.
Nat Commun ; 12(1): 2456, 2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33911084

RESUMO

The phytohormone abscisic acid (ABA) is crucial for plant responses to environmental challenges. The SNF1-regulated protein kinase 2s (SnRK2s) are key components in ABA-receptor coupled core signaling, and are rapidly phosphorylated and activated by ABA. Recent studies have suggested that Raf-like protein kinases (RAFs) participate in ABA-triggered SnRK2 activation. In vitro kinase assays also suggest the existence of autophosphorylation of SnRK2s. Thus, how SnRK2 kinases are quickly activated during ABA signaling still needs to be clarified. Here, we show that both B2 and B3 RAFs directly phosphorylate SnRK2.6 in the kinase activation loop. This transphosphorylation by RAFs is essential for SnRK2 activation. The activated SnRK2s then intermolecularly trans-phosphorylate other SnRK2s that are not yet activated to amplify the response. High-order Arabidopsis mutants lacking multiple B2 and B3 RAFs show ABA hyposensitivity. Our findings reveal a unique initiation and amplification mechanism of SnRK2 activation in ABA signaling in higher plants.

11.
Commun Biol ; 4(1): 305, 2021 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-33686174

RESUMO

Pneumocystis jirovecii, the fungal agent of human Pneumocystis pneumonia, is closely related to macaque Pneumocystis. Little is known about other Pneumocystis species in distantly related mammals, none of which are capable of establishing infection in humans. The molecular basis of host specificity in Pneumocystis remains unknown as experiments are limited due to an inability to culture any species in vitro. To explore Pneumocystis evolutionary adaptations, we have sequenced the genomes of species infecting macaques, rabbits, dogs and rats and compared them to available genomes of species infecting humans, mice and rats. Complete whole genome sequence data enables analysis and robust phylogeny, identification of important genetic features of the host adaptation, and estimation of speciation timing relative to the rise of their mammalian hosts. Our data reveals insights into the evolution of P. jirovecii, the sole member of the genus able to infect humans.

12.
Nat Prod Res ; : 1-7, 2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33736548

RESUMO

Two new piericidins A5 (1) and G1 (2), a previously synthesized piericidin G2 (3), and two known piericidins A1 (4) and A2 (5) were isolated from the marine-derived Streptomyces sp. SCSIO 40063. The structures of 1-5 were elucidated by HRESIMS, 1 D, 2 D NMR data analyses and comparisons with the known compounds. Compound 2 showed moderate cytotoxicities against four human tumor cell lines SF-268, MCF-7, HepG2 and A549 with IC50 values between 10.0 and 12.7 µM.

13.
Neurosci Lett ; 750: 135810, 2021 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-33705929

RESUMO

Although clinical efficacy of waggle needling has been confirmed, therapeutic mechanisms still remain poorly understood. Reduction of GABA was involved in the etiology of spasticity. Recently, accumulated evidences suggest that the inhibitory effect of GABA is determined by low intracellular chloride concentration, which is predominantly mediated by KCC2. This study was designed to investigate whether KCC2-GABAA pathway was involved in the mechanism underlying acupuncture intervention in rats with middle cerebral artery occlusion (MCAO). Three days after modeling, the rats received waggle needling, routine needling and placebo needling for 7 consecutive days. After treatment, the muscle spasticity, motor function and infarct volumes were tested. KCC2 and GABAAγ2 levels were detected via western blotting, RT-PCR and immunofluorescence. KCC2 antagonist and agonist were administered after the last intervention. We found that acupuncture, particularly waggle needling, could remarkably alleviate muscle spasticity, reverse motor deficits and reduce cerebral infraction in MCAO rats, possibly due to its effects on up-regulating expressions of KCC2 and GABAAγ2 in the cortical infarct regions. However, the effects were blocked by KCC2 antagonist. In summary, this study suggests that improvements in muscle spasticity and motor function induced by waggle needling correlates with the activation of KCC2-GABAA pathway.

14.
Ecotoxicol Environ Saf ; 215: 112150, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33756290

RESUMO

To estimate spatial distribution, source analysis and uncertainty of heavy metals (Pb, Cd, Cr, Hg, As, Cu, Zn, and Ni) based on geographic information system (GIS), positive matrix factorization model (PMF) and bootstrap (BS) using 382 soil samples collected from cultivated soils in Lanzhou. The mean contents of Cd, Hg, Cu, Zn and Ni were high as 1.7,1.7, 2.1, 1.5 and 1.3 times local background values, mean contents of Pb, Cr and As were lower than local background values. However, the mean contents of eight heavy metals were lower environmental quality risk control standard for soil contamination of agricultural soil. Proportions of four sources were identified: Cr was predominantly contributed by natural sources (29.14%), Cu, Zn and Ni was primarily from industrial sources (25.26%), Hg and As were mainly of agricultural sources (27.49%), Pb and Cd mainly came from traffic source and smelting-related activities (18.09%). Uncertainties analysis contained three aspects: bootstrap runs, factor contributions in the PMF solution, and coefficient of variation (CV) values. By combining the four pollution source factors with bootstrap runs, the accuracy of the four pollution source factors were reliable based on PMF model. The median values in the BS runs was considered the most true factor contribution, and the 5th-95th quartile interval represents the variability of each factor, Factor 4 (traffic source) R2 was 0.70 and lower variability. The highest CV value usually means a significantly deviation degree. In this study, the CV values of Cr in Factor 1, Cu, Zn, and Ni in Factor 2, Hg, and As in Factor 3, Pb, and Cd in Factor 4 were lower, indicates a lower deviation degree. and with the lowest content among heavy metals usually was also with the greatest uncertainties. In this study improves understanding of the reduction of heavy metal pollution in cultivated soil, and also serves as reference for pollution source apportionment in other regions.


Assuntos
Monitoramento Ambiental , Metais Pesados/análise , Poluentes do Solo/análise , Agricultura , China , Correlação de Dados , Poluição Ambiental/análise , Sistemas de Informação Geográfica , Indústrias , Mercúrio/análise , Medição de Risco , Solo , Incerteza
15.
Molecules ; 26(4)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33670784

RESUMO

The fungus strain SCSIO 40433 was isolated from an Arctic-derived glacier sediment sample and characterized as Tolypocladium cylindrosporum. A new compound, cylindromicin (1), and seven known secondary metabolites (2-8) were isolated from this strain. The chemical structures of these compounds were elucidated by comprehensive spectroscopic analyses. Cylindromicin (1) featured a 3,4-dihydro-2H-pyran skeleton. The absolute configuration of compound 1 was assigned via interpretation of key Nuclear Overhauser Effect Spectroscopy (NOESY) correlations and Electronic Circular Dichroism (ECD) calculation. Cylindromicin (1) exhibited significant tyrosinase inhibition activity. This study highlights Polar fungi as a potential resource for new bioactive natural products.


Assuntos
Hypocreales/química , Piranos/isolamento & purificação , Regiões Árticas , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Testes de Sensibilidade Microbiana , Espectroscopia de Prótons por Ressonância Magnética , Piranos/química , Piranos/farmacologia , Pironas/química , Pironas/farmacologia , Relação Estrutura-Atividade
16.
Biol Lett ; 17(3): 20200873, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33726564

RESUMO

Montane reptiles are predicted to move to higher elevations in response to climate warming. However, whether upwards-shifting reptiles will be physiologically constrained by hypoxia at higher elevations remains unknown. We investigated the effects of hypoxic conditions on preferred body temperatures (Tpref) and thermal tolerance capacity of a montane lizard (Phrynocephalus vlangalii) from two populations on the Qinghai-Tibet Plateau. Lizards from 2600 m a.s.l. were exposed to O2 levels mimicking those at 2600 m (control) and 3600 m (hypoxia treatment). Lizards from 3600 m a.s.l. were exposed to O2 levels mimicking those at 3600 m (control) and 4600 m (hypoxia treatment). The Tpref did not differ between the control and hypoxia treatments in lizards from 2600 m. However, lizards from 3600 m selected lower body temperatures when exposed to the hypoxia treatment mimicking the O2 level at 4600 m. Additionally, the hypoxia treatment induced lower critical thermal minimum (CTmin) in lizards from both populations, but did not affect the critical thermal maximum (CTmax) in either population. Our results imply that upwards-shifting reptiles may be constrained by hypoxia if a decrease in Tpref reduces thermally dependent fitness traits, despite no observed effect on their heat tolerance.


Assuntos
Lagartos , Aclimatação , Animais , Regulação da Temperatura Corporal , Hipóxia , Temperatura , Tibet
17.
Mol Plant ; 14(5): 805-819, 2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-33676025

RESUMO

Manganese (Mn) is an essential micronutrient in plants. However, excessive Mn absorption in acidic and waterlogged soils can lead to Mn toxicity. Despite their essential roles in Mn homeostasis, transcriptional and post-transcriptional modifications of Mn transporters remain poorly understood. Here, we demonstrated that high-Mn stress induces an obvious Ca2+ signature in Arabidopsis. We identified four calcium-dependent protein kinases, CPK4/5/6/11, that interact with the tonoplast-localized Mn and iron (Fe) transporter MTP8 in vitro and in vivo. The cpk4/5/6/11 quadruple mutant displayed a dramatic high-Mn-sensitive phenotype similar to that of the mtp8 mutant. CPKs phosphorylated the N-terminal domain of MTP8 primarily at the Ser31 and Ser32 residues. Transport assays combined with multiple physiological experiments on phospho-dead variant MTP8S31/32A and phospho-mimetic variant MTP8S31/32D plants under different Mn and Fe conditions suggested that Ser31 and Ser32 are crucial for MTP8 function. In addition, genetic analysis showed that CPKs functioned upstream of MTP8. In summary, we identified a tonoplast-associated calcium signaling cascade that orchestrates Mn homeostasis and links Mn toxicity, Ca2+ signaling, and Mn transporters. These findings provide new insight into Mn homeostasis mechanisms and Ca2+ signaling pathways in plants, providing potential targets for engineering heavy metal toxicity-tolerant plants.

18.
Stereotact Funct Neurosurg ; : 1-6, 2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33756470

RESUMO

OBJECTIVE: The aim of this study was to evaluate the efficacy of Gamma Knife radiosurgery (GKRS) as a salvage therapy for high-grade glioma in our center. METHODS: A total of 167 patients with malignant glioma were treated with GKRS in our Gamma Knife Center between January 2013 and December 2017; 140 patients (85 males and 55 females) were followed up and enrolled in our study. A single lesion was found in 110 cases, and multiple lesions were found in 30 cases; 108 cases received a single therapy, and in 32 cases, at least 2 GKRSs were performed. The median tumor volume was 13.5 cm3. The mean radiation dosage was 14.35 Gy (range, 6-18 Gy). MRI was performed regularly. The RANO criteria and Cox analysis were used to evaluate the therapeutic efficiency. RESULTS: Follow-up MRI showed the local control rate was 61.4% at 3 months after GKRS, 25.0% at 6 months, and 7.1% at 12 months. The mean and median progression-free survival (PFS) periods were 8.6 (95% CI, 6.3-11.0) and 4 (95% CI, 3.5-4.5) (range, 1-60) months, respectively. The overall survival (OS) after GKRS was 3-62 months, with a mean of 16.7 (95% CI, 14.6-18.9) months, and the median survival was 13 (95% CI, 12.1-13.9) months. The 1-, 2-, and 5-year survival rates were 51.4, 10.0, and 2.9%, respectively. No severe complications occurred. Cox regression showed that glioma pathology was closely related to prognosis (p < 0.05). The Karnofsky Performance Score had little influence on PFS (p > 0.05) but influenced OS significantly (p < 0.05). CONCLUSION: GKRS can be used to effectively treat malignant brain glioma and can therefore be used as an alternative treatment option.

19.
Nanoscale ; 13(12): 6024-6029, 2021 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-33651053

RESUMO

Magnetic semiconductors with high critical temperature have long been the focus in materials science and are also known as one of the fundamental questions in two-dimensional (2D) materials. Based on density functional theory calculations, we predict a 2D spin-gapless ferromagnetic semiconductor of CrGa2Se4 monolayer, in which the type of spin-polarized current can be tuned by tailoring the Fermi energy. Moreover, the magnetic anisotropy energy calculations indicate that the CrGa2Se4 monolayer possesses spin anisotropy both in the basal plane and the vertical plane. This originates from the distortion-induced rearrangement of the 3d electrons in the CrSe6 octahedron and results in an inclined easy axis out of the film. The Curie temperature (Tc) of ferromagnetic phase transition for 2D CrGa2Se4 is more than 200 K. This 2D material shows promising transport properties for spintronics applications and is also important for fundamental research in 2D magnetism.

20.
Food Res Int ; 141: 110056, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33641958

RESUMO

The effects of pulsed ultrasound treatment (250 W, 0-12 min) on gel and physicochemical properties of porcine myosin at low-salt group (0.3 mol/L) and control groups (0.6 and 0.9 mol/L) were investigated. The texture and water holding capacity (WHC) of low-salt group gel were remarkably lower than in medium-salt (0.6 mol/L) and high-salt group (0.9 mol/L). However, 6-min ultrasound treatment could obviously improve the texture and WHC of low-salt group gel. After ultrasound treatment, the protein solubility was increased, as the degree of protein aggregation was reduced. Simultaneously, ultrasound treatment led to unfolding of protein structure and increasing surface hydrophobicity. The three-dimensional network of myosin gel gradually became uniform by 6-min ultrasound treatment. Under 12-min ultrasound treatment, the protein aggregated excessively during the gelation, which led to the deterioration of gel quality. These results suggested that moderate ultrasound treatment is promising to be used to enhance the quality of salt-reduced meat products.

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