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1.
BMC Cancer ; 21(1): 418, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33858382

RESUMO

BACKGROUND: The potential correlation between H2AFY (also known as MacroH2A1) and the clinical characteristics of hepatocellular carcinoma (HCC) patients was analysed through gene expression profiles and clinical data in The Cancer Genome Atlas (TCGA) database, and the diagnostic and prognostic value of H2AFY in HCC was discussed. METHODS: The gene expression data of HCC and the corresponding clinical characteristics of HCC patients were downloaded from the TCGA database. The differences in H2AFY in normal liver tissues and HCC were analysed. The relationship between H2AFY and clinical characteristics was analysed by Wilcoxon signed-rank test, logistic regression and Kruskal-Wallis test. The Kaplan-Meier method and the Cox regression method were used to analyse the relationship between overall survival and clinical characteristics of the patients. An ROC curve was used to predict the diagnostic value of H2AFY in HCC. Gene set enrichment analysis (GSEA) was used to analyse the pathway enrichment of H2AFY. RESULT: Compared with normal liver tissues, H2AFY was significantly highly expressed in HCC. H2AFY was positively correlated with the age, clinical stage, G stage (grade) and T stage (tumor stage) of liver cancer patients. Higher H2AFY expression predicted a poor prognosis in HCC patients. Cox regression analysis suggested that H2AFY was an independent risk factor for the prognosis of HCC patients. The ROC curve suggested that H2AFY had certain diagnostic value in HCC. GSEA suggested that H2AFY was correlated with lipid metabolism and a variety of tumour pathways. CONCLUSION: Our study showed that H2AFY was significantly overexpressed in HCC. H2AFY may be a potential diagnostic and prognostic marker for HCC, and high expression of H2AFY predicts a poor prognosis in patients with HCC.

2.
Chem Asian J ; 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33881805

RESUMO

Peroxalate CL as an energy source to excite photosensitizers has attracted tremendous attention in photodynamic therapy (PDT). In this work, peroxyoxalate CPPO and hypocrellin B (HB)-based nanoparticles (CBNPs) for ultrasound (US)-enhanced self-exciting PDT were designed and prepared. CBNPs showed an excellent therapeutic effect against cancer cells with the assistance of US. This US-enhanced-chemiluminescence system avoids the dependence on external light and provides an example for inspiring more effective and precise strategies for cancer treatment.

3.
Life Sci ; 278: 119529, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33894270

RESUMO

Glomerular podocyte damage is considered to be one of the main mechanisms leading to Diabetic nephropathy (DN). However, the relevant mechanism of podocyte injury is not yet clear. This study aimed to investigate the effect of peroxiredoxin 6 (Prdx6) on the pathogenesis of podocyte injury induced by high glucose (HG). The mouse glomerular podocyte MPC5 was stimulated with 30 nM glucose, and the Prdx6 overexpression vector or specificity protein 1 (Sp1) overexpression vector was transfected into MPC5 cells before the high glucose stimulation. As results, HG treatment significantly reduced the expression of Prdx6 and Sp1 in MPC5 cells. Prdx6 overexpression increased cell viability, while inhibited podocyte death, inflammation and podocyte destruction in HG-induced MPC5 cells. Prdx6 overexpression inhibited HG-induced ROS and MDA production, while restored SOD and GSH activity in MPC5 cells. Prdx6 overexpression also eliminated ferroptosis caused by HG, which was reflected in the suppression of iron accumulation and the increase in SLC7A11 and GPX4 expression. The improvement effect of Prdx6 on HG-induced podocyte damage could be eliminated by erastin. Moreover, Sp1 could bind to the three Sp1 response elements in the Prdx6 promoter, thereby directly regulating the transcriptional activation of Prdx6 in podocytes. Silencing Sp1 could eliminate the effect of Prdx6 on HG-induced podocyte damage. Further, Prdx6 overexpression attenuated renal injuries in streptozotocin-induced DN mice. Sp1-mediated upregulation of Prdx6 expression prevents podocyte injury in diabetic nephropathy via mitigation of oxidative stress and ferroptosis, which may provide new insights for the study of the mechanism of DN.

4.
BMC Med Imaging ; 21(1): 75, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33902469

RESUMO

BACKGROUND: Multiple guidelines for pancreatic ductal adenocarcinoma (PDAC) suggest that all stages of patients need to receive postoperative adjuvant chemotherapy. S-1 is a recently emerged oral antitumour agent recommended by the guidelines. However, which population would benefit from S-1 needs to be determined, and predictors of chemotherapy response are needed for personalized precision medicine. This pilot study aimed to initially identify whether whole-tumour evaluation with MRI and radiomics features could be used for predicting the efficacy of S-1 and to find potential predictors of the efficacy of S-1 as evidence to assist personalized precision treatment. METHODS: Forty-six patients with PDAC (31 in the primary cohort and 15 in the validation cohort) who underwent curative resection and subsequently adjuvant chemotherapy with S-1 were included. Pre-operative abdominal contrast-enhanced MRI was performed, and radiomics features of the whole PDAC were extracted from the primary cohort. After univariable analysis and radiomics features selection, a multivariable Cox regression model for survival analysis was subsequently used to select statistically significant factors associated with postoperative disease-free survival (DFS). Predictive capacities of the factors were tested on the validation cohort by using Kaplan-Meier method. RESULTS: Multivariable Cox regression analysis identified the probability of T1WI_NGTDM_Strength and tumour location as independent predictors of the efficacy of S-1 for adjuvant chemotherapy of PDAC (p = 0.005 and 0.013) in the primary cohort, with hazard ratios (HRs) of 0.289 and 0.293, respectively. Further survival analysis showed that patients in the low-T1WI_NGTDM_Strength group had shorter DFS (median = 5.1 m) than those in the high-T1WI_NGTDM_Strength group (median = 13.0 m) (p = 0.006), and patients with PDAC on the pancreatic head exhibited shorter DFS (median = 7.0 m) than patients with tumours in other locations (median = 20.0 m) (p = 0.016). In the validation cohort, the difference in DFS between patients with low-T1WI_NGTDM_Strength and high-T1WI_NGTDM_Strength and the difference between patients with PDAC on the pancreatic head and that in other locations were approved, with marginally significant (p = 0.073 and 0.050), respectively. CONCLUSIONS: Whole-tumour radiomics feature of T1WI_NGTDM_Strength and tumour location were potential predictors of the efficacy of S-1 and for the precision selection of S-1 as adjuvant chemotherapy regimen for PDAC.

5.
Int J Infect Dis ; 2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33862216

RESUMO

OBJECTIVES: Hypermucoviscous Klebsiella pneumoniae is an emerging cause of community-acquired liver abscess. We aimed to investigate if hypermucoviscous strains could be shared among households. METHODS: We genotyped the clinical K. pneumoniae isolates in a cohort of 24 patients with Klebsiella liver abscess and analyzed the stool metagenomes of the index patients and their cohabiting domestic partners. RESULTS: We identified K. pneumoniae in 33% of index patient's stools and identified one index patient's clinical isolate in their domestic partner's stool. CONCLUSIONS: This could represent a transmission event or could represent exposure to a common environmental source.

6.
Int Urol Nephrol ; 2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33905043

RESUMO

OBJECTIVE: To explore the efficacy and safety of rituximab (RTX) in the treatment of autoimmune nephropathy manifested as refractory nephrotic syndrome (RNS). METHODS: A single-center prospective cohort study was conducted on RNS patients treated with RTX between March 2017 and December 2019. The subjects were divided into the primary nephropathy (PN) group and the secondary nephropathy (SN) group. Based on the estimated glomerular filtration rate (eGFR) before RTX treatment, the SN group was then divided into the SN-1 group (eGFR ≥ 30 ml/min) and the SN-2 group (eGFR < 30 ml/min). Biochemical parameters and clinical data were recorded during follow-up. RESULTS: Fifty-four patients were followed up for at least 6 months. The overall remission rates were 65%, 66.7%, 27.3% in the PN, SN-1, and SN-2 groups, respectively (P = 0.022). Kaplan-Meier analysis showed a significant difference of the renal survival among the three subgroups (P < 0.001). Multivariate Cox regression analysis showed that eGFR value before treatment was an independent predictor (HR 0.919, 95%CI 0.863-0.979) for renal survival. In terms of adverse events, infection accounted for 56.6%. The incidence of severe infection was 10%, 25% and 50% in PN group, SN-1 group and SN-2 group, respectively. CONCLUSIONS: RTX may be a promising option in RNS patients with eGFR ≥ 30 ml/min/1.73m2. However, it has little effect on prognosis in patients with secondary RNS with eGFR < 30 ml/min/1.73m2, but with a high risk of severe infection.

7.
Neural Regen Res ; 16(11): 2276-2283, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33818513

RESUMO

Axon regeneration and remyelination of the damaged region is the most common repair strategy for spinal cord injury. However, achieving good outcome remains difficult. Our previous study showed that porcine decellularized optic nerve better mimics the extracellular matrix of the embryonic porcine optic nerve and promotes the directional growth of dorsal root ganglion neurites. However, it has not been reported whether this material promotes axonal regeneration in vivo. In the present study, a porcine decellularized optic nerve was seeded with neurotrophin-3-overexpressing Schwann cells. This functional scaffold promoted the directional growth and remyelination of regenerating axons. In vitro, the porcine decellularized optic nerve contained many straight, longitudinal channels with a uniform distribution, and microscopic pores were present in the channel wall. The spatial micro topological structure and extracellular matrix were conducive to the adhesion, survival and migration of neural stem cells. The scaffold promoted the directional growth of dorsal root ganglion neurites, and showed strong potential for myelin regeneration. Furthermore, we transplanted the porcine decellularized optic nerve containing neurotrophin-3-overexpressing Schwann cells in a rat model of T10 spinal cord defect in vivo. Four weeks later, the regenerating axons grew straight, the myelin sheath in the injured/transplanted area recovered its structure, and simultaneously, the number of inflammatory cells and the expression of chondroitin sulfate proteoglycans were reduced. Together, these findings suggest that porcine decellularized optic nerve loaded with Schwann cells overexpressing neurotrophin-3 promotes the directional growth of regenerating spinal cord axons as well as myelin regeneration. All procedures involving animals were conducted in accordance with the ethical standards of the Institutional Animal Care and Use Committee of Sun Yat-sen University (approval No. SYSU-IACUC-2019-B034) on February 28, 2019.

8.
Adv Exp Med Biol ; 1256: 191-200, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33848002

RESUMO

Age-related macular degeneration (AMD) is a multifactorial neurodegenerative disease, which is a leading cause of vision loss among the elderly in the developed countries. As one of the most successful examples of genome-wide association study (GWAS), a large number of genetic studies have been conducted to explore the genetic basis for AMD and its progression, of which over 30 loci were identified and confirmed. In this chapter, we review the recent development and findings of GWAS for AMD risk and progression. Then, we present emerging methods and models for predicting AMD development or its progression using large-scale genetic data. Finally, we discuss a set of novel statistical and analytical methods that were recently developed to tackle the challenges such as analyzing bilateral correlated eye-level outcomes that are subject to censoring with high-dimensional genetic data. Future directions for analytical studies of AMD genetics are also proposed.


Assuntos
Degeneração Macular , Doenças Neurodegenerativas , Idoso , Progressão da Doença , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Degeneração Macular/genética
9.
Andrologia ; : e14065, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33822394

RESUMO

The retrospective cohort study was conducted to evaluate the effectiveness of preimplantation genetic testing for aneuploidy (PGT-A) for severe male factor (SMF) infertility on pregnancy outcomes in comparison with intracytoplasmic sperm injection (ICSI). A total of 206 couples with SMF were included in the study, among which, 102 couples underwent ICSI with next-generation sequencing (NGS)-based PGT-A (the PGT-A group), while 104 underwent ICSI only (the control group). Results showed while no differences were noted in clinical pregnancy rate (CPR) (66.7% versus. 69.9%, p = .64) and ongoing pregnancy rate (OPR) (62.2% versus. 54.7%, p = .29) per transfer between groups, early miscarriage rate (EMR) per transfer was significantly lower (6.7% versus. 21.6%, p = .02) in the PGT-A group. Cumulative OPR per patient remained similar between groups (54.9% versus. 55.8%, p = .90). Results of multivariable logistic regression also demonstrated the use of PGT-A was significantly associated with lower EMR (adjusted OR 0.17, 95%CI 0.05-0.55) in SMF, while it was not related to cumulative OPR. In conclusion, our results showed that NGS-based PGT-A can improve pregnancy outcomes for couples with SMF by significantly decreasing EMR without compromising cumulative OPR, indicating that NGS-based PGT-A could be offered as an appropriate approach for couples with SMF.

10.
J Pharm Pharmacol ; 73(3): 388-397, 2021 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-33793880

RESUMO

OBJECTIVES: To determine the kinetics of the formation of 10,11-dihydro-10-hydroxy-carbazepine (MHD)-O-glucuronide in human liver microsomes (HLMs), human intestine microsomes (HIMs), human kidney microsomes (HKMs) and recombinant human UDP-glucuronosyltransferase (UGTs), and identify the primary UGT isoforms catalyzing the glucuronidation of MHD. METHODS: The kinetics of the glucuronidation of MHD was determined in HLMs, HIMs as well as HKMs. Screening assays with 13 recombinant human UGTs, inhibition studies and correlation analysis were performed to identify the main UGTs involved in the glucuronidation of MHD. KEY FINDINGS: MHD-O-glucuronide was formed in HLMs, HIMs as well as HKMs, HLMs showed the highest intrinsic clearance of MHD. Among 13 recombinant human UGTs, UGT2B7 and UGT1A9 were identified to be the principal UGT isoforms mediating the glucuronidation of MHD, while UGT1A4 played a partial role. In addition, inhibition studies and correlation analysis further confirmed that UGT2B7 and UGT1A9 participated in the formation of MHD-O-glucuronide. CONCLUSIONS: MHD could be metabolized by UGTs in the liver, intestine and kidney, and the hepatic glucuronidation was the critical metabolic pathway. UGT2B7 and UGT1A9 were the primary UGT isoforms mediating the formation of MHD-O-glucuronide in the liver.

11.
J Phys Chem Lett ; : 3795-3801, 2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33848144

RESUMO

Integrated optics shows great potential in the current optical communication systems, sensor technology, optical computers, and other fields. Tunable laser technology within a certain range is the key to achieving on-chip optical integration; to realize which, Raman scattering is a competitive method that can effectively transfer incident laser energy to optical phonons due to the photon-phonon interaction. Here, we take hexagonal boron nitride as the energy conversion medium, and based on the angle-resolved polarized Raman spectroscopy, it is found that when laser polarization vector ei ⊥ c axis, the spectrum obtains maximal scattering across the cross section and a minimal depolarization ratio. At room temperature, h-BN obtains an output signal with a wavelength of 522.8 nm and a full-width at half-maximum of 0.24 nm under the excitation of 488 nm pump laser, and the depolarization ratio is 0.09 (theoretically, it is 0, and this difference is due to experimental errors). And then, within the temperature range of 80∼420 K, the scattered light wavelength shows a high-precision shift of 0.006 nm/25 K, indicating that continuous wavelength tuning has been successfully achieved in h-BN.

12.
Ecotoxicol Environ Saf ; 215: 112163, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33756288

RESUMO

Cadmium (Cd) contamination has become serious in soil and in situ stabilization technology has been widely used for heavy metal remediation. A field study was conducted to determine the effect of amendments with the doses of 3 kg/m2, including single vermicompost (A1), a 95% vermicompost mixed with 5% shell powder composite (A2) and a 95% vermicompost mixed with 5% modified shell powder composite (A3), on the Cd bioavailability, enzyme activity and bacterial community in soil, and the experiment was conducted with lettuce (Lactuca sativa L.) grown in a Cd-contaminated farmland soil. The results showed that the application of amendments increased the pH, cation exchange capacity (CEC), organic matter (OM), available nutrients, catalase (S-CAT), invertase (S-SC) and urease (S-UE) activities in soil, while significantly reduced the Cd bioavailability with the lowest Cd bioavailability being observed in the soil with A3 application. The soil bacterial richness and diversity increased after amendments application, and the bacterial community was characterized by an increase in metal-tolerant bacteria but a decrease in Proteobacteria, Acidobacteria and Gemmatimonadetes. In addition, the application of amendments significantly improved the growth of lettuce (Lactuca sativa L.) and inhibited Cd accumulation in its edible parts, especially, the Cd content in lettuce (Lactuca sativa L.) grown in soil with A3 application was below the limit of the National Food Safety Standard of China (maximum level ≤ 0.2 mg/kg). Thus, composite amendment obtained from vermicompost mixed with modified shell powder can be used as potential remediation material in Cd-contaminated soil. CAPSULE: Composite amendment obtained from vermicompost and modified shell powder had good effects on remediation of Cd-contaminated soil.


Assuntos
Cádmio/análise , Microbiologia do Solo , Poluentes do Solo/análise , Acidobacteria , Bactérias , Disponibilidade Biológica , China , Poluição Ambiental , Fazendas , Alface , Metais Pesados , Pós , Proteobactérias , Solo/química , Urease
14.
Sci Total Environ ; 778: 146378, 2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33725595

RESUMO

Silicon, in its nanoscale form, has shown plant-promoting and insecticidal properties. To date, however, we lack mechanistic evidence for how nanoscale silicon influences the regulation of plant chemical defenses against herbivore attacks. To address this gap, we compared the effect of Si nanodots (NDs) and sodium silicate, a conventional silicate fertilizer, on maize (Zea mays L.) chemical defenses against the oriental armyworm (Mythimna separata, Walker) caterpillars. We found that Si NDs and sodium silicate additions, at the dose of 50 mg/L, significantly inhibited the growth of caterpillars by 53.5% and 34.2%, respectively. This increased plant resistance was associated with a 44.2% increase in the production of chlorogenic acid, as well as the expression of PAL, C4H, 4CL, C3H and HCT, core genes involved in the biosynthesis of chlorogenic acid, by 1.7, 2.4, 1.9, 1.8 and 4.5 folds, respectively. Particularly, in the presence of M. separata, physiological changes in maize plants treated with 50 mg/L Si NDs, including changes in shoot biomass, leaf nutrients (e.g., K, P, Si), and chemical defense compounds (e.g., chlorogenic acid, total phenolics), were higher than those of plants added with equivalent concentrations of conventional silicate fertilizer. Taken together, our findings indicate that Si, in nanoscale form, could replace synthetic pesticides, and be implemented for a more effective and ecologically-sound management of insect pests in maize crop farming.

15.
Biom J ; 2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33751636

RESUMO

In modern drug development, genotype information becomes more frequently collected in randomized controlled trials (RCTs) for individualized risk prediction and personalized medicine development. Finding single nucleotide polymorphisms (SNPs) that are predictive of differential treatment efficacy, measured by a clinical outcome, is fundamentally different and more challenging than the traditional association test for a quantitative trait. With the objective to confidently identify and infer genetic subgroups with enhanced treatment efficacy from a large RCT for an eye disease, age-related macular degeneration (AMD), where the clinical endpoint is binary (progressed or not), we propose a novel SNP-testing procedure for binary clinical outcomes. Specifically, we formulate four contrasts to simultaneously assess all possible genetic effects on a logic-respecting efficacy measure, the relative risk (between treatment and control). Our method controls both within- and across-SNP multiplicity rigorously. We then use real genotype data to perform chromosome-wide simulations to evaluate our method performance and to provide practical recommendations. Finally, we apply the proposed method to perform a genome-wide SNP testing for the AMD trial and successfully identify multiple gene regions with genetic subgroups exhibiting enhanced efficacy in terms of decreasing the AMD progression rate.

16.
Metabolism ; 119: 154749, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33722534

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is the most common metabolic and endocrine disorder among reproductive-age women, and the leading cause of anovulatory infertility. 11ß-hydroxysteroid dehydrogenases-1 (11ß-HSD1) catalysing the conversion of inactive cortisone to active cortisol plays a crucial role in various metabolic diseases. However, whether 11ß-HSD1 is associated with the pathogenesis of PCOS and whether 11ß-HSD1 can be a treating target of PCOS remain unknown. METHODS: This study was first designed to explore the role of 11ß-HSD1 in PCOS development and the effect of selective 11ß-HSD1 inhibitor administration on PCOS treatment. Follicular fluid and granulosa cells (GCs) were collected from 32 non-PCOS patients and 37 patients with PCOS to measure cortisol and 11ß-HSDs levels. Female Sprague-Dawley rats (3-week-old) were injected with dehydroepiandrosterone (DHEA) to induce PCOS and their ovaries were collected to measure the abundance of corticosterone (CORT) and 11ß-HSDs. To determine the role of 11ß-HSD1 in PCOS development, we overexpressed 11ß-HSD1 in the ovaries of female rats (5-week-old) or knocked down the expression of 11ß-HSD1 in the ovaries from PCOS rats via lentivirus injection. After lentivirus infection, the body weights, ovarian weights, estrous cycles, reproductive hormones and morphology of the ovary were analysed in rats from different experimental groups. Then to figure out the translational potential of the selective 11ß-HSD1 inhibitor in treating PCOS, PCOS rats were treated with BVT.2733, a selective 11ß-HSD1 inhibitor and a cluster of PCOS-like traits were analysed, including insulin sensitivity, ovulatory function and fertility of rats from the Control, PCOS and PCOS+BVT groups. Rat ovarian explants and human GCs were used to explore the effect of CORT or cortisol on ovarian extracellular matrix remodelling. RESULTS: The elevated expression of 11ß-HSD1 contributed to the increased cortisol and corticosterone (CORT) concentrations observed in the ovaries of PCOS patients and PCOS rats respectively. Our results showed that ovarian overexpression of 11ß-HSD1 induced a cluster of PCOS phenotypes in rats including irregular estrous cycles, reproductive hormone dysfunction and polycystic ovaries. While knockdown of ovarian 11ß-HSD1 of PCOS rats reversed these PCOS-like changes. Additionally, the selective 11ß-HSD1 inhibitor BVT.2733 alleviated PCOS symptoms such as insulin resistance (IR), irregular estrous cycles, reproductive hormone dysfunction, polycystic ovaries, ovulatory dysfunction and subfertility. Moreover, we showed that cortisol target ovarian insulin signalling pathway and ovarian extracellular matrix (ECM) remodelling in vivo, in ovarian explants and in GCs. CONCLUSION: Elevated 11ß-HSD1 abundance in ovarian is involved in the pathogenesis of PCOS by impairing insulin signalling pathway and ECM remodelling. Selective inhibition of 11ß-HSD1 ameliorates a cluster of PCOS phenotypes. Our study demonstrates the selective 11ß-HSD1 inhibitor as a novel and promising strategy for the treatment of PCOS.

17.
Eur J Med Chem ; 217: 113372, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33744689

RESUMO

Diabetes mellitus is one of the most challenging threats to global public health. To improve the therapy efficacy of antidiabetic drugs, numerous drug delivery systems have been developed. Polyethylene glycol (PEG) is a polymeric family sharing the same skeleton but with different molecular weights which is considered as a promising material for drug delivery. In the delivery of antidiabetic drugs, PEG captures much attention in the designing and preparation of sustainable and controllable release systems due to its unique features including hydrophilicity, biocompatibility and biodegradability. Due to the unique architecture, PEG molecules are also able to shelter delivery systems to decrease their immunogenicity and avoid undesirable enzymolysis. PEG has been applied in plenty of delivery systems such as micelles, vesicles, nanoparticles and hydrogels. In this review, we summarized several commonly used PEG-contained antidiabetic drug delivery systems and emphasized the advantages of stimuli-responsive function in these sustainable and controllable formations.

18.
Water Environ Res ; 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33780582

RESUMO

The most effective pretreatment method for the detection of dissolved organic nitrogen (DON) is the nanofiltration (NF) by effectively intercepting DON into the concentrated solution, thus increasing the proportion of DON in solution so that achieving accurate detection of DON. The existing NF pretreatment technology for detection of DON has the problem of low accuracy and unclear separation mechanism of mass transfer upon the NF membranes. Based on the problems of NF membrane, the polyether sulfone (PES) composite NF membrane was modified by mesoporous carbon and the basic performance parameters of the modified PES composite NF membrane were characterized by Static contact angle (SCA), Zeta potential, and X-ray photoelectron spectroscopy (XPS). The results show that the optimum doping amount of mesoporous carbon is in the range of 0.5%-1.0%. Furthermore, the pore size of NF membrane could be controlled effectively by changing doping amount of mesoporous carbon, so as to guide the improvement of membrane pore structure. After the pretreatment of mesoporous material modified PES composite NF membrane, the ratio of dissolved inorganic nitrogen (DIN)/total dissolved nitrogen (TDN) could be reduced to 0.55-0.65 and the pretreatment effect was also affected by screening effect and electrostatic effect. The best retention performance of amino acids is the 1.0%C modified membrane which retention rate of the amino acid is between 32.3% and 94.7%, and the membrane loss of the four amino acids is much smaller than other membranes. The mass transfer process of NF membrane was simulated by steric-hindrance pore (SHP) model, Teorell-Meyer-Sievers (TMS) model, and Electrostatic Steric-hindrance (ES) model respectively. According to the simulation software designed by ourselves, the dominant effects of screening and electrostatic effects are simultaneously affected by the pore structure of membranes and the size of the contaminant molecules. PRACTITIONER POINTS: The feasibility of mesoporous carbon with modified PES composite nanofiltration membrane pretreatment for DON measurement in comparison to pure NF membranes was investigated. The ability of modified PES composite NF membrane with different molecular weight of DON and the relationship between pore radius of membrane and interception pollutant molecular size was discussed. The influence of screening effect and electrostatic effect on the retention of pollutants was discussed by the SHP model, TMS model and ES model; the simulation software interface is designed and the calculation process of the model is simulated by computer.

19.
CNS Neurosci Ther ; 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33763978

RESUMO

AIMS: This study was aimed to investigate whether electroacupuncture (EA) would increase the secretion of neurotrophin-3 (NT-3) from injured spinal cord tissue, and, if so, whether the increased NT-3 would promote the survival, differentiation, and migration of grafted tyrosine kinase C (TrkC)-modified mesenchymal stem cell (MSC)-derived neural network cells. We next sought to determine if the latter would integrate with the host spinal cord neural circuit to improve the neurological function of injured spinal cord. METHODS: After NT-3-modified Schwann cells (SCs) and TrkC-modified MSCs were co-cultured in a gelatin sponge scaffold for 14 days, the MSCs differentiated into neuron-like cells that formed a MSC-derived neural network (MN) implant. On this basis, we combined the MN implantation with EA in a rat model of spinal cord injury (SCI) and performed immunohistochemical staining, neural tracing, electrophysiology, and behavioral testing after 8 weeks. RESULTS: Electroacupuncture application enhanced the production of endogenous NT-3 in damaged spinal cord tissues. The increase in local NT-3 production promoted the survival, migration, and maintenance of the grafted MN, which expressed NT-3 high-affinity TrkC. The combination of MN implantation and EA application improved cortical motor-evoked potential relay and facilitated the locomotor performance of the paralyzed hindlimb compared with those of controls. These results suggest that the MN was better integrated into the host spinal cord neural network after EA treatment compared with control treatment. CONCLUSIONS: Electroacupuncture as an adjuvant therapy for TrkC-modified MSC-derived MN, acted by increasing the local production of NT-3, which accelerated neural network reconstruction and restoration of spinal cord function following SCI.

20.
Scientometrics ; : 1-19, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33746309

RESUMO

COVID-19 cases have surpassed the 109 + million markers, with deaths tallying up to 2.4 million. Tens of thousands of papers regarding COVID-19 have been published along with countless bibliometric analyses done on COVID-19 literature. Despite this, none of the analyses have focused on domain entities occurring in scientific publications. However, analysis of these bio-entities and the relations among them, a strategy called entity metrics, could offer more insights into knowledge usage and diffusion in specific cases. Thus, this paper presents an entitymetric analysis on COVID-19 literature. We construct an entity-entity co-occurrence network and employ network indicators to analyze the extracted entities. We find that ACE-2 and C-reactive protein are two very important genes and that lopinavir and ritonavir are two very important chemicals, regardless of the results from either ranking.

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