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1.
J Hazard Mater ; 382: 121023, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31476717

RESUMO

Pesticide residues pose a great threat to human health, and it is an urgent matter to realize fast and accurate detection of pesticide. SERS (Surface Enhanced Raman Scattering), as a nondestructive detection technology, performs a prominent role in fast detection field due to the strong surface plasmon resonance from short range effect between analyte and nanoparticle. Therefore, in order to solve the incompatibility between organochlorine pesticides molecules and noble metal nanoparticles, this paper proposed a concept of "bridge" substances acting as an interconnect function role to achieve a binding model (object-binder-metal (OBM)) and developed a droplet concentration method to enhance Raman signals. Both combination mode of pesticide molecules to bridge molecules and energy transfer of SERS experiment may relate to the compound ring according to the changes of peaks based on surface plasmon resonance. The selectivity and stability of different bridge substances interacting with pesticides molecules were illumined via binding energy of these two substances obtained by DFT calculations. A droplet can capture nanoparticles and analytes, which is conducive to SERS performance. Chloride ions in the solution contribute to rearrangement of nanoparticles and can validly promote surface activation of Ag nanoparticles to improve energy transfer efficiency of plasma resonance, resulting in superior SERS effect.

2.
Curr Top Med Chem ; 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31721704

RESUMO

BACKGROUND: Breast plastic surgery is a rapidly evolving field in medicine. The modern view of surgical trends reflects the desire to minimize complications and introduce advanced technologies. These always will be priorities for surgeons. Reconstructive surgery, a branch of plastic surgery focusing on restoration of lost functional and aesthetic component, seeks to enhance psychological rehabilitation and improve quality of life, as well as aesthetic recovery. OBJECTIVE: This review addresses the action of fibrin agents and their effect on the quality of surgical hemostasis. DISCUSSION AND CONCLUSION: The fundamental goals for the surgeon are to perform a minimally traumatic intervention and to prevent any form of complication. Achieving complete hemostasis is an intraoperative necessity. Timely prevention of bleeding and hemorrhagic phenomena can affect not only the outcome of the operation, but also the incidence of postoperative complications. Topics include the integrity of microvascular anastomoses, tissue adhesion, and the incidence of seromas and hematomas associated with fibrin glue usage. The literature on fibrin adhesives with respect to prevention of postoperative complications, and the effectiveness with active drainage also are analyzed.

3.
Acta Biomater ; 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31672583

RESUMO

Protein-templated gold nanoclusters have attracted attention in fluorescence imaging due to their simple synthesis and good biocompatibility. However, limitations still exist such as poor colloid stability and undesirable fluorescence intensity. Here we describe the self-assembly of keratin-templated gold nanoclusters via a simple and mild preparation process, including keratin-templated synthesis of gold nanoclusters (AuNCs@Keratin), silver ions modification of AuNCs@Keratin (AuNCs-Ag@Keratin), and gadolinium ions-induced aggregation of AuNCs-Ag@Keratin (AuNCs-Ag@Keratin-Gd). It was demonstrated that the AuNCs-Ag@Keratin-Gd obtained an enhanced fluorescence intensity (6.5 times that of AuNCs@Keratin), high colloid stability for more than 4 months, and good biocompatibility. Moreover, the AuNCs-Ag@Keratin-Gd holds promise in multifunctional applications such as near-infrared (NIR) fluorescence imaging, magnetic resonance (MR) imaging, and redox-responsive drug delivery, extending the applicability of fluorescent gold nanoclusters, especially in biomedical fields. STATEMENT OF SIGNIFICANCE: Assembly-induced fluorescence enhancement has been rarely reported on as it relates to the protein-templated gold nanoclusters (AuNCs). In this work, self-assembly of protein-templated AuNCs was developed for enhanced fluorescence intensity and multifunctional applications, including bioimaging and responsive drug delivery. A cysteine-rich protein, keratin, was utilized as the template to synthesize AuNCs, which underwent silver ion modification and gadolinium ion-induced aggregation. The silver modification of the keratin-templated AuNCs facilitated the formation of a dense aggregate after gadolinium ion-induced assembly, thus generating an enhanced fluorescence intensity. Such a mechanism was confirmed by fluorescence correlation spectroscopy analysis. We believe that this work will extend the applicability of the fluorescent gold nanoclusters, especially in biomedical fields, and provided an effective approach for the mechanism analysis of the assembly-induced fluorescence enhancement via fluorescence correlation spectroscopy.

4.
Int J Biol Macromol ; 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31669658

RESUMO

In this study, four sequentially extracted polysaccharides (AEPs) from Amana edulis were modified by sulphation, phosphorylation, and carboxylation modifications (S-AEPs, P-AEPs, C-AEPs), and compared for their anti-oxidant activities. After modification, sugar and protein contents were decreased and uronic acid content was increased in comparison to native AEPs. UV absorption showed similar maximum absorption peaks of modified derivatives which indicated their homogeneous nature. FTIR spectra confirmed the conversion of hydroxyl groups to OS, COO, and POH bonds, respectively. The phosphorylated derivatives (P-AEPs) displayed the highest DPPH, hydroxyl radical, and ferrous ions radical scavenging abilities. Sulfated polysaccharides (S-AEPs) were observed with high reducing ability. The C-AEPs maintained the stable antioxidant properties after carboxylation modification. Our results indicated that the chemical modification of different polysaccharide components has significantly affected their antioxidant potential for their use in food industry and human health.

5.
ACS Appl Mater Interfaces ; 11(45): 41853-41861, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31668068

RESUMO

Nowadays, multicolored drug carriers have exhibited high significance in designing self-illuminating drug delivery systems to adapt different experimental conditions. In this study, we developed an efficient strategy for self-illuminating antitumor therapy using multicolored aggregation-induced emission (AIE)-active drug carriers by tuning electron donor moieties in donor-acceptor (D-A) structures. Three amphipathic conjugated polymers, P1 to P3, were successfully synthesized using an AIE-active tetraphenylethylene (TPE) moiety and donor-acceptor (D-A)-type electronic structure. Interestingly, the fluorescence behavior of P1 to P3 could be tuned between aggregation-caused quenching and AIE by changing the electron donor moiety. Their fluorescence color in aqueous solution could be easily adjusted from yellow to red by choosing stronger electron donors. After the anticancer drug paclitaxel was loaded, two AIE-active polymers, P1 and P2, could be engineered into polymer dots (Pdots) and applied in self-illuminating cancer therapy. The Pdots could not only reveal their location by a yellow- or red-colored fluorescence signal but also exhibit almost two times in vivo antitumor efficacy, high biocompatibility, and obvious tumor-targeting behavior compared to the commercially available anticancer drug Taxol. Furthermore, P2dots exhibited similar in vivo antitumor efficacy and biocompatibility compared to nonemission Abraxane, a commercially available drug delivery system. This work demonstrates the significant application of a D-A-type structure in the design of self-illuminating drug delivery systems.

6.
Front Immunol ; 10: 2250, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31681259

RESUMO

T cells play a key role in cell-mediated immunity, and strategies to genetically modify T cells, including chimeric antigen receptor (CAR) T cell therapy and T cell receptor (TCR) T cell therapy, have achieved substantial advances in the treatment of malignant tumors. In clinical trials, CAR-T cell and TCR-T cell therapies have produced encouraging clinical outcomes, thereby demonstrating their therapeutic potential in mitigating tumor development. This article summarizes the current applications of CAR-T cell and TCR-T cell therapies in clinical trials worldwide. It is predicted that genetically engineered T cell immunotherapies will become safe, well-tolerated, and effective therapeutics and bring hope to cancer patients.

7.
Int J Biol Macromol ; 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31712142

RESUMO

Fulminant hepatitis (FH) is a severe liver disease characterized by extensive hepatic necrosis, oxidative stress, and inflammation. Myricetin (Myr), a botanical flavonoid glycoside, is recognized to exert antiapoptosis, anti-inflammatory, and antioxidant properties. In the current study, we focused on exploring the protective effects and underlying mechanisms of Myr against lipopolysaccharide (LPS) and D-galactosamine (D-GalN)-induced FH. These data indicated that Myr effectively protected from LPS/D-GalN-induced FH by lowering the mortality of mice, decreasing ALT and AST levels, and alleviating histopathological changes, oxidative stress, inflammation, and hepatic apoptosis. Moreover, Myr could efficiently mediate multiple signaling pathways, displaying not only the regulation of caspase-3/9 and P53 protein, inhibition of toll-like receptor 4 (TLR4)-nuclear factor-kappa B (NF-κB) activation, and -mitogen-activated protein kinase (MAPK), but also the increase of heme oxygenase-1 (HO-1) and nuclear factor-erythroid 2-related factor 2 (Nrf2) expression, as well as induction of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) phosphorylation in mice with LPS/D-GalN-induced FH. Importantly, our further results in vitro suggested that Myr remarkably attenuated H2O2-triggered hepatotoxicity and ROS generation, activated Keap1-Nrf2/HO-1 and AMPK/ACC signaling pathway. However, Myr-enhanced the expression of HO-1 and Nrf2 protein was reversed by Keap1-overexpression, Nrf2-null and AMPK inhibitor. Meanwhile, Myr-relieved hepatotoxicity excited by H2O2 was blocked by Nrf2-null and AMPK inhibitor. Taken together, Myr exhibits a protective role against LPS/D-GalN-induced FH by suppressing hepatic apoptosis, inflammation, and oxidative stress, likely involving in the regulation of apoptosis-related protein, TLR4-NF-κB/-MAPK and NLRP3 inflammasome, and AMPK-Nrf2/HO-1 signaling pathway.

8.
Cell Prolif ; : e12694, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31568642

RESUMO

OBJECTIVES: Mesenchymal stem cell (MSC)-based dental tissue regeneration is a potential treatment method in future, while inflammation and hypoxia niche will affect MSC-mediated tissue regeneration. In this research, we intended to investigate the influence and mechanism of secreted frizzled-related protein 2(SFRP2) on MSC function under inflammation and hypoxia conditions. MATERIAL AND METHODS: Stem cells from apical papilla (SCAPs) were used in this study. The alkaline phosphatase (ALP) activity, Alizarin Red S staining, scratch-simulated wound migration and transwell chemotaxis assay were used to evaluate the functions of SFRP2. The Western blot, real-time RT-PCR and ChIP assays were used to evaluate the mechanism of SFRP2. RESULTS: Under inflammation and hypoxia conditions, the over-expression of SFRP2 could enhance the osteo/odontogenic differentiation ability. Mechanismly, SFRP2 inhibited canonical Wnt/ß-catenin signalling pathway and then inhibited the target genes of nuclear factor kappa B (NFkB) signalling pathway. Inflammation or hypoxia conditions could promote the expression of lysine demethylase 2A (KDM2A) and repress SFRP2 transcription through decreasing histone methylation in the SFRP2 promoter. Besides, proteomic analysis showed that SFRP2 promoted SCAPs to secret more functional cytokines, which improve the migration, chemotaxis and osteo/odontogenic ability of MSCs. CONCLUSIONS: Our discoveries revealed that SFRP2 enhanced the osteo/odontogenic differentiation and paracrine potentials of SCAPs under hypoxia and inflammation conditions and provided a potential cytokine for promoting tissue regeneration in hypoxia and inflammatory niche.

9.
Nat Commun ; 10(1): 4914, 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31664033

RESUMO

Mitofusin-2 (MFN2) is a dynamin-like GTPase that plays a central role in regulating mitochondrial fusion and cell metabolism. Mutations in MFN2 cause the neurodegenerative disease Charcot-Marie-Tooth type 2A (CMT2A). The molecular basis underlying the physiological and pathological relevance of MFN2 is unclear. Here, we present crystal structures of truncated human MFN2 in different nucleotide-loading states. Unlike other dynamin superfamily members including MFN1, MFN2 forms sustained dimers even after GTP hydrolysis via the GTPase domain (G) interface, which accounts for its high membrane-tethering efficiency. The biochemical discrepancy between human MFN2 and MFN1 largely derives from a primate-only single amino acid variance. MFN2 and MFN1 can form heterodimers via the G interface in a nucleotide-dependent manner. CMT2A-related mutations, mapping to different functional zones of MFN2, lead to changes in GTP hydrolysis and homo/hetero-association ability. Our study provides fundamental insight into how mitofusins mediate mitochondrial fusion and the ways their disruptions cause disease.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31566428

RESUMO

The transient receptor potential canonical 6 (TRPC6) channel and podocin are co-localized in the glomerular slit diaphragm as an important complex to maintain podocyte function. Gain of TRPC6 function and loss of podocin function induce podocyte injury. We have previously shown that high glucose induces apoptosis of podocytes by activating TRPC6; however, whether the activated TRPC6 can alter podocin expression remains unknown. Western blot, confocal microscopy, and scanning ion conductance microscopy were used to examine both the expression levels of TRPC6, podocin, and nephrin and the morphological change of podocytes in response to high glucose. High glucose increased the expression of TRPC6, but reduced the expression of podocin and nephrin, both in cultured human podocytes and in type 1 diabetic rat kidney. The decreased podocin was diminished in TRPC6 knockdown podocytes. High glucose elevated intracellular calcium in control podocytes, but not in TRPC6 knockdown podocytes. High glucose also elevated the expression of a tight junction protein, zonula occludens-1 (ZO-1) and induced the redistribution of ZO-1 and the loss of podocyte processes. These data together suggest that high glucose reduces the protein levels of podocin by activating TRPC6 and induces morphological changes of cultured podocytes.

11.
Sci Rep ; 9(1): 14717, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31605003

RESUMO

The prognostic nutritional index (PNI) has been applied in acute myocardial infarction (AMI) recently.However, the application of PNI in AMI needs verification. This was a prospective cohort study. Patients diagnosed with AMI were enrolled. PNI was calculated as (serum albumin (SA in g/L)) + (5 × total lymphocyte count (TLC) × 109/L). Modified PNI (mPNI) was analyzed by logistic regression analysis to reset the proportion of SA and TLC. The primary outcome was all-cause death. A total of 598 patients were enrolled; 73 patients died during follow-up. The coefficient of SA and TLC in the mPNI formula was approximately 2:1. The area under the receiver operating characteristic curve of SA, TLC, PNI, mPNI and GRACE in predicting death for patients with AMI was 0.718, 0.540, 0.636, 0.721 and 0.825, respectively. Net reclassification improvement (NRI) between PNI and mPNI was 0.230 (p < 0.001). Integrated discrimination improvement (IDI) was 0.042 (p = 0.001). Decision curve analysis revealed that mPNI had better prognostic value for patients with AMI than PNI; however, it was not superior to SA. Thus, PNI may not a reliable prognostic predictor of AMI; after resetting the formula, the value of PNI in predicting prognosis of AMI is almost entirely due to SA.

12.
Mol Oncol ; 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31600013

RESUMO

Recurrence and metastasis are the major causes of mortality in head and neck squamous cell carcinoma (HNSCC). It is suggested that cancer stem cells (CSCs) play pivotal roles in recurrence and metastasis. Thus, a greater understanding of the mechanisms of CSC regulation may provide opportunities to develop novel therapies for improving survival by controlling recurrence or metastasis. Here, we report that overexpression of the gene encoding the catalytic subunit of PI3K (PIK3CA), the most frequently amplified oncogene in HNSCC, promotes epithelial-to-mesenchymal transition and enriches the CSC population. However, PIK3CA is not required to maintain these traits and inhibition of the phosphatidylinositol 3-kinase (PI3K) signaling pathway paradoxically promotes CSC population. Molecular analysis revealed that overexpression of PIK3CA activates multiple receptor tyrosine kinases (RTKs), in which ephrin receptors (Ephs), tropomyosin receptor kinases (TRK) and mast/stem cell growth factor receptor (c-Kit) contribute to maintain CSC population. Accordingly, simultaneous inhibition of these RTKs using a multi-kinase inhibitor ponatinib has a superior effect at eliminating the CSC population and reduces metastasis of PIK3CA-overexpressing HNSCC cells. Our result suggests that co-targeting of Ephs, TRKs and the c-Kit pathway may be effective at eliminating the PI3K-independent CSC population, thereby providing potential targets for future development of a novel anti-CSC therapeutic approach for HNSCC patients, particularly for patients with PIK3CA amplification.

13.
J Cell Physiol ; 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31621904

RESUMO

It has been reported that the proliferation and apoptosis of mammary epithelial cells affect milk production. Therefore, ensuring adequate mammary epithelial cells is expected to enhance milk production. This study is devoted to studying the effects of kisspeptin-10 (Kp-10), a peptide hormone composed of 10 amino acids, on bovine mammary epithelial cell (bMEC) proliferation and exploring the underlying mechanism of its action. bMECs were treated with various concentrations of Kp-10 (1, 10, 100, and 1,000 nM), and 100 nM Kp-10 promoted the proliferation of the bMECs. Kp-10 promoted the cell cycle transition from G1 to the S and G2 phases, increased the protein levels of Cyclin D1 and Cyclin D3, and reduced the expression levels of the p21 gene. This study also showed that inhibition of G protein-coupled receptor 54 (GPR54), AKT, mTOR, and ERK1/2 reduced the proliferation of the bMECs that had been induced by Kp-10. In addition, Kp-10 decreased the complexes formed by Rb and E2F1 and increased the expression levels of the E2F1 target genes. These results indicate that Kp-10 promotes bMEC proliferation by activating GPR54 and its downstream signaling pathways.

14.
Adv Mater ; : e1904163, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31592566

RESUMO

Light-emitting diodes (LEDs) based on solution-processed metal halide perovskites have shown great application potential in energy-efficient lighting and displays. Multiple-quantum-well (MQW) perovskites simultaneously possess high photoluminescence quantum efficiency and good film morphology and stability, making it attractive for high-performance perovskite LEDs. Here, merits of MQW perovskites and the progress in MQW perovskite LEDs are reviewed. Challenges and future directions of perovskite LEDs are also discussed.

15.
Pancreas ; 48(9): e70-e71, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31609937
16.
Br J Neurosurg ; : 1-7, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31601135

RESUMO

Aim: After brachial plexus injuries, sacrifice of the contralateral C7 (cC7) root from the non-injured side is well tolerated and various schemes to innervate the injured side from the cC7 root have been used. Objective: To demonstrate the surgical outcomes from transferring the cC7 to the affected side via both the ulnar nerve and medial antebrachial cutaneous nerve (MACN). Methods: A retrospective study of 16 adult patients sustaining total brachial plexus avulsion who underwent this procedure. The British Medical Research Council (MRC) grading system and the disabilities of the arm, shoulder, and hand (DASH) questionnaire scoring were used to evaluate the recovery. Results: About 68.75% of the patients achieved functional recovery of elbow flexion to M3 or better and 43.75% achieved motor recovery of wrist and finger flexion to M3 or better. Sensation in the median nerve territory recovered to S2 or better in 68.75%. The DASH scores after surgery were significantly lower than those before surgery. Conclusions: cC7 transfer via both ulnar and MACNs is an effective and safe procedure in patients sustaining total injuries of brachial plexus.

17.
Brain Behav ; 9(11): e01449, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31631587

RESUMO

OBJECTIVES: Animal studies have shown that glutamate receptor ionotropic kainate 2 (GRIK2) gene knockout mice are more impulsive and aggressive. This study aims to verify whether the rs6922753 and rs2227283 polymorphisms of the GRIK2 gene are associated with both aggressive behavior and bipolar mania in the Chinese Han population. METHODS: Polymerase chain reaction (PCR) was applied in the genotype rs6922753 and rs2227283 polymorphisms of the GRIK2 gene in 201 bipolar manic patients with aggressive behaviors, 198 bipolar manic patients without aggressive behaviors, and 132 healthy controls. The Modified Overt Aggression Scale (MOAS) was used to evaluate aggressive behavior in patients with bipolar mania. RESULTS: No correlation was found between aggressive behavior and the rs6922753 polymorphism in the three groups. The A/A genotype and A allele of the rs2227283 polymorphism were found significantly more frequently in patients with aggressive behavior than in healthy controls (p = .004 and p = .013, respectively) and in patients with nonaggressive behavior (p = .002 and p = .018, respectively). The A/A genotype and A allele were associated with an increased risk of aggressive behavior. CONCLUSION: This study suggests that the rs2227283 polymorphism of the GRIK2 gene is related to aggressive behaviors in bipolar manic patients and that the A/A genotype and A allele may increase the risk of the aggressive behavior in bipolar manic patients.

18.
Cell Death Dis ; 10(9): 672, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31511501

RESUMO

Lipid metabolism that correlates tightly to the glucose metabolic regulation in malignant cells includes hepatocellular carcinoma (HCC) cells. The transcription factor Sterol Regulatory Element Binding Protein 1 (SREBP-1), a regulator of fatty acid synthesis, has been shown to pivotally regulate the proliferation and metastasis of HCC cells. However, the intrinsic mechanism by which SREBP-1 regulates the survival of HCC cells remains unclear. In this study, among HCC patients who had dismal responses to Sorafenib, a high SREBP-1 level was found in the tumors and correlated to poor survival. This observation suggested the negative role of SREBP-1 in clinical HCC prognosis. Our mechanistical studies reveal that the inhibition of SREBP-1 via its inhibitor Betulin suppresses cellular glucose metabolism. In addition to the reduced glycolytic activity, a thwarted metastatic potential was observed in HCC cells upon Betulin administration. Moreover, our data show that SREBP-1 inhibition facilitated the antitumor effects of Sorafenib on HCC cells and xenograft tumors.

19.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 33(9): 1162-1168, 2019 Sep 15.
Artigo em Chinês | MEDLINE | ID: mdl-31512460

RESUMO

Objective: To study the expressions of microRNA-221 (miR-221) and the protein of phosphatase and tension protein homologue (PTEN) in the proximal and distal stumps after sciatic nerve injury in rats and their correlation with the repair of peripheral nerve injury, so as to provide a new target for clinical diagnosis of peripheral nerve injury. Methods: Ninety-six male Sprague-Dawley rats of SPF grade were selected to establish sciatic nerve injury models. Twenty-four rats were sacrificed at 0 (immediately after operation), 1, 4, and 7 days after operation. The proximal and distal sciatic nerve fragments were taken under aseptic conditions. The expression of miR-221 was detected by real-time fluorescent quantitative PCR, and the expression of PTEN protein was detected by Western blot and immunofluorescent staining. The relationship between miR-221 and PTEN was verified by dual-luciferase reporter gene. At the same time, the ultrastructure of nerve stump was observed by transmission electron microscopy. Results: The results of real-time fluorescent quantitative PCR, Western blot, and immunofluorescence staining showed that the relative expression of miR-221 in the proximal and distal stumps increased gradually with time, and the relative expression of PTEN protein decreased gradually, and the differences between different time points after operation were significant ( P<0.05). At 1, 4, and 7 days after operation, the relative expression of miR-221 in proximal stump was significantly higher than that in distal stump, and the relative expression of PTEN protein in proximal stump was significantly lower than that in distal stump ( P<0.05). Dual-luciferase reporter gene suggested that PTEN was the target for miR-221. Transmission electron microscopy observation showed that the normal morphological structure was observed at 0 day after operation, and the proliferation of Schwann cells and degeneration of axons and myelin sheaths gradually increased with time. There was no significant difference between proximal and distal stumps at 1 day after operation. At 4 and 7 days, Schwann cells proliferated more in proximal stump than in distal stump, and the degeneration of axons and myelin sheaths was less. Conclusion: After sciatic nerve injury in rats, the up-regulation of the miR-221 expression targets the down-regulation of PTEN expression, which results in the difference of expression levels of miR-221 and PTEN in proximal and distal stumps. This phenomenon may play a role in promoting nerve repair after peripheral nerve injury.


Assuntos
Regulação da Expressão Gênica , MicroRNAs , PTEN Fosfo-Hidrolase , Traumatismos dos Nervos Periféricos , Nervo Isquiático , Animais , Axônios , Masculino , MicroRNAs/genética , Regeneração Nervosa/genética , PTEN Fosfo-Hidrolase/genética , Traumatismos dos Nervos Periféricos/fisiopatologia , Ratos , Ratos Sprague-Dawley , Nervo Isquiático/fisiopatologia
20.
Bioresour Technol ; 294: 122149, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31563741

RESUMO

In this work, agricultural waste edible fungus slag derived nitrogen-doped hierarchical porous carbon (EFS-NPC) was prepared by a simple carbonization and activation process. Owing to the biodegradation and infiltrability of hyphae, this EFS-NPC possessed an ultra-high specific surface area (3342 m2/g), large pore volume (1.84 cm3/g) and abundant micropores and mesopores. The obtained EFS-NPC could effectively adsorb bisphenol A (BPA) with the maximal adsorption capacity of 1249 mg/g and the removal process reached 89.9% of the equilibrium uptake in the first 0.5 h. Besides, the EFS-NPC showed much better removal performance towards 2,4-dichlorophenol (2,4-DCP) and methylene blue (MB) than commercial activated carbons (Norit RO 0.8 and DARCO granular activated carbon). Furthermore, adsorption isotherms, thermodynamics and kinetics researches indicated that the adsorption process of BPA was monolayer, exothermic and spontaneous. This research has given evidence that the low-cost EFS-NPC can serve as a high-efficient adsorbent for removing organic contaminants from water.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Fungos , Cinética , Nitrogênio , Porosidade , Água
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