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1.
J Nanosci Nanotechnol ; 20(2): 789-801, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383074

RESUMO

Magnetic Ni0.5Cu0.5Fe2O4/SiO2 nanocomposites were prepared via a solution combustion process, and were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), Energy dispersive X-ray Spectroscopy (EDX) and vibrating sample magnetometer (VSM). The magnetic Ni0.5Cu0.5Fe2O4/SiO2 nanocomposites were employed to remove Congo red (CR) from aqueous solution, and the adsorption process was optimized by response surface methodology (RSM). The optimum conditions were the silica content of 12.6 wt%, the calcination temperature of 501 °C and the pH value of 7.13. The adsorption kinetics and the adsorption isotherm of CR onto magnetic Ni0.5Cu0.5Fe2O4/SiO2 nanocomposites at room temperature were investigated, and the intraparticle diffusion kinetics model and Redlich-Peterson isotherm model fitted well the respective process.

2.
Food Chem ; 308: 125665, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31655473

RESUMO

The effects of different dissolved oxygen concentrations (DOC) on the browning degree, amino acids, total phenols, reducing sugars, polyphenoloxidase (PPO), peroxidase (POD), phenylalanine ammonia-lyase (PAL) of pear wine, and the relationship between various quality indicators and browning degree were investigated. Dynamic model fitting analysis of the changes of physiochemical indicators of pear wine in the storage process were performed. The importance of the physiochemical indicators effect on the browning of pear wine during the storage process was analyzed by OPLS (orthogonal partial least squares discriminant analysis), and the effect of dissolved oxygen on the browning of pear wine was systematically revealed. The results showed that dissolved oxygen, total phenols and amino acids had the greatest influence on the browning degree of pear wine. It provided a theoretical basis for revealing the browning mechanism and inhibiting the browning of pear wine.

3.
Molecules ; 24(23)2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31795356

RESUMO

In this study, the aroma compounds of Huantai tartary buckwheat tea (TBH), three laboratory-produced scented tartary buckwheat teas, as well as the antioxidant activity of tea infusion was investigated. In total, 103 aroma components were isolated and identified from all samples. Tartary buckwheat rose tea (TBR) contained 57 aroma components and tartary buckwheat jasmine tea (TBJ) had 53, both of which were higher than those in others. In addition, the total flavonoid content (TFC) and the total phenolic content (TPC) of scented tartary buckwheat tea were much higher than those of TBH. After the tartary buckwheat tea (TBT) was soaked in hot water twice, the antioxidant activity of all samples decreased, and the antioxidant activity of TBR and TBJ infusions was more stable than those of others. Further, the antioxidant activity of the first tea infusion (FTI) of the TBT was higher than that of the second tea infusion (STI). Overall, considering the diverse aroma compounds of scented tartary buckwheat tea and higher antioxidant activity of tea infusions, the combination of scented tea and tartary buckwheat is a feasible approach to develop tartary buckwheat scented tea.

4.
Am J Cardiol ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31784053

RESUMO

Cardiac involvement in autoimmune diseases (AD) is common but underdiagnosed due to a lack of sensitive imaging methods. We aim to evaluate the characteristics of left ventricular (LV) systolic dysfunction in patients with AD using deformational parameters from 2-dimensional speckle-tracking echocardiography (STE). We retrospectively enrolled 86 AD patients and 71 healthy controls. All subjects underwent transthoracic echocardiography and STE to analyze LV strain and twist. A twist-radial displacement loop was constructed to investigate the relation between LV contractility and dimension. In AD patients, 68 had preserved LV ejection fraction (EF ≥ 50%), and 18 had reduced LVEF (EF < 50%). The patients with preserved LVEF exhibited significantly lower values of global longitudinal, circumferential, and radial strain than controls (-19.11 ± 4.18 vs -21.49 ± 2.53%, -25.17 ± 5.04% vs -27.37 ± 2.87%, 17.68 ± 5.69% vs 21.17 ± 6.44%, respectively; all p <0.01) and a marked attenuation in peak twist (14.24 ± 5.57 vs 18.10 ± 5.97, p <0.01) attributed to impaired apical rotation (9.03 ± 5.17 vs 12.79 ± 5.99, p <0.01). AD patients were more likely to present with abnormal loop types with flat ascending slope and delayed peak twist time. In conclusion, abnormal strain and twist precede deterioration in LVEF, suggesting early myocardial involvement in AD. STE can be used as a good alternative for early detection of myocardial dysfunction in AD patients.

5.
Mol Imaging Biol ; 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31792837

RESUMO

PURPOSE: The cystine transporter, system xC-, plays a crucial role in sustaining redox homeostasis and is reported to be overexpressed in several cancer subtypes. 5-[18F]Fluoroaminosuberic acid ([18F]FASu) is a novel positron emission tomography (PET) tracer, which exhibits specific uptake via system xC-. [18F]FASu synthesis by the commonly used Kryptofix 2.2.2/K2CO3-facilitated fluorination method results in four diastereomers, as a result of 2 chiral centers at positions 2- and 5- of the tracer. We recently reported the synthesis of the optically pure 2S-[18F]FASu from chiral precursors. Our preliminary results indicated preferential uptake of the 2S-isomer by tumor cells compared to 2R-[18F]FASu. Few studies have investigated the biodistribution of chiral 18F-labeled amino acids. The aim of this study was to evaluate the imaging utility and biodistribution of the 5-position diastereomers as well as the racemic (2S,5R/S-) mixture in three different tumor models. PROCEDURES: In vitro tracer uptake experiments and Western blotting were performed in breast cancer (MDA-MB-231), glioblastoma (U-87), and prostate (PC-3) cancer cell lines. PET imaging and biodistribution studies were conducted in xenograft-bearing immunocompromised Rag2M female mice. RESULTS: All three tracer conformations allowed for the visualization of tumor xenografts at 1 h (for U-87 and PC-3 tumors) or 2 h (in the case of MDA-MB-231 xenografts) post-injection, with the racemate (2S,5R/S-) displaying similar image contrast as compared to the 5- position diastereomers and the 2S,5S-[18F]FASu conformation exhibiting relatively higher contrast for imaging U-87 and PC-3 xenografts. Tumor uptake of the isomers was blocked by an excess of the non-radioactive standard, aminosuberic acid (ASu), confirming target specificity. All three isomers were excreted via the renal pathway. Biodistribution analyses showed that PC-3 tumors had the highest tracer uptake, and the accumulation (%ID/g) of the 2S,5R/S-, 2S,5S-, and 2S,5R- isomers was 9.19 ± 1.14, 8.00 ± 1.41, and 7.16 ± 2.13 at 1 h post-injection, respectively. This gave corresponding tumor-to-muscle ratios of 33.68 ± 9.52, 31.42 ± 4.54, and 25.33 ± 4.97, respectively. CONCLUSION: Our data suggest that pure 2S-[18F]FASu can be used to noninvasively image system xC- in a variety of cancers, either as the racemic mixture (2S,5R/S-) or optically pure form. Furthermore, this work shows potential utility of [18F]FASu for detection of glioblastoma and prostate cancer.

6.
J Clin Lab Anal ; : e23137, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31793694

RESUMO

BACKGROUND: Role of plasma vitamin D and genetic variants of its receptor (VDR) in susceptibility to different diseases has been documented. Various studies in different populations have been highlighted strong associations with diabetes and cardiovascular diseases. Vitamin D deficiency has been linked with the development of type 2 diabetes (T2D) and the onset of coronary artery diseases (CAD). However, the role of vitamin D in predisposition to CAD in patients with T2D is ill-defined. MATERIALS AND METHODS: We enrolled 674 Chinese T2D patients, and based on clinical phenotype, patients were further categorized into patients with (n = 138) or without coronary artery disease (n = 536). Five hundred twenty-one healthy subjects from similar geographical areas, free from diabetic or coronary disorders, were enrolled as controls. Serum levels of 25-OH vitamin D were quantified by ELISA. Common VDR (FokI, TaqI, BsmI, and ApaI) polymorphisms were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). RESULTS: Patients with T2D displayed lower levels of 25-OH vitamin D compared with healthy controls. Furthermore, T2D patients with CAD clinical phenotype had the lowest levels of vitamin D. Prevalence of FokI and TaqI mutants was significantly higher in diabetic patients when compared to controls. Interestingly, Tt genotype was more frequent in the artery disease group in comparison with T2D patients without heart involvement. Combined analysis of VDR polymorphisms and serum levels of vitamin D revealed a significant role in predisposition to T2D with or without CAD. CONCLUSIONS: Lower vitamin D levels and variants of VDR polymorphisms (FokI and TaqI) are associated with susceptibility to T2D and clinical manifestation.

7.
World J Surg Oncol ; 17(1): 206, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31801560

RESUMO

BACKGROUND: Malignant transformation of endometriosis in the rectovaginal septum is rare and usually misdiagnosed as a colorectal or gynecological tumor. We report a rare case of primary endometrioid adenocarcinoma of the rectovaginal septum with invasion of the rectum. CASE PRESENTATION: A 57-year-old overweight woman presented with vaginal bleeding and self-reported left lower abdominal pain during the previous 2 weeks. Preoperative imaging showed a large pelvic mass with invasion of the rectum, suggestive of a gynecologic malignancy. Multiple endoscopic biopsies and immunohistochemical analyses of specimens was performed. The patient received joint gynecological-surgical laparotomy, and there were no intra- or postoperative complications. The histopathological diagnosis was rectovaginal endometrioid adenocarcinoma with rectum infiltration. The patient received adjuvant chemotherapy and achieved good treatment response, with no early complications. At 12 months after surgery, there was no evidence of recurrence. CONCLUSIONS: A high index of clinical suspicion is required for the diagnosis of endometrioid adenocarcinoma in the rectovaginal septum. Surgery combined with additional chemotherapy or radiotherapy seems to be a standard treatment, and hormonal therapy is optional. The efficacies of other therapies, including targeted medication and immunotherapy, are unknown.

8.
Medicine (Baltimore) ; 98(49): e18264, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31804362

RESUMO

BACKGROUND: LncRNA HNF1A Antisense RNA 1 (HNF1A-AS1) is often dysregulated in cancer. We performed this meta-analysis to clarify the usefulness of HNF1A-AS1 as a prognostic marker in malignant tumors. METHODS: The PubMed, OVID, and Web of Science databases were searched from inception to January 11, 2018. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated to explore the relationship between HNF1A-AS1 expression and survival. Odds ratios (OR) were calculated to assess the association between HNF1A-AS1 expression and pathological parameters. RESULTS: Eight studies with a total of 802 patients were included in the study. The pooled hazard ratio (HR) suggested high HNF1A-AS1 expression correlated with poor overall survival (OS) (HR = 4.85, 95% confidence interval (CI): 2.43-9.68), and disease-free survival (DFS) (HR = 6.34, 95% CI: 1.03-39.12) in cancer patients. High HNF1A-AS1 expression also correlated with poor histological grade (OR = 1.88, 95% CI: 1.27-2.79), high tumor stage (OR = 4.04, 95% CI: 2.53-6.47), lymph node metastasis (LNM) (OR = 4.53, 95% CI: 2.30-8.92), and distant metastasis (OR = 5.99, 95% CI: 2.88-12.48). Begg funnel plot did not show any evidence of obvious asymmetry for high tumor stage (Pr > |z| = 0.368) and LNM (Pr > |z| = 1.000). CONCLUSIONS: Thus high HNF1A-AS1 expression is predictive of poor OS, DFS, lymph node metastasis, distant metastasis, histological grade, and larger tumor stage, which suggests high HNF1A-AS1 expression may serve as a novel biomarker of poor prognosis in cancer.

9.
J Chromatogr A ; : 460628, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31753484

RESUMO

Hawthorn is a popular functional food. In China, Crataegus pinnatifida Bunge. and C. pinnatifida Bge. var. major N. E. Brown are two major species that are used for the preparation of hawthorn products. Accordingly, it is crucial to explore the chemical differences between these two species for the market standardization of hawthorn products. In this study, we integrated manual annotation with untargeted metabolomics based on ultra-high performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry for compound characterization and discrimination of the two hawthorn species. We characterized 78 compounds in the two species including saccharides, glycosides, organic acids, phenols, flavonoids and triterpenoids. Moreover, 47 differential compounds and 17 false positive ions were recognized and fully reviewed. The 47 identified compounds were then used to build a partial least squares discriminant analysis model that successfully discriminated C. pinnatifida Bge. and C. pinnatifida Bge. var. major N.E.Br.

10.
Curr Top Med Chem ; 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31763974

RESUMO

Cilostazol is a unique platelet inhibitor that has been used clinically for more than 20 years. As a phosphodiesterase type III inhibitor, cilostazol is capable of reversible inhibition of platelet aggregation and vasodilation, has antiproliferative effects, and is widely used in the treatment of peripheral arterial disease, cerebrovascular disease, percutaneous coronary intervention, etc. This article briefly reviews the pharmacological mechanisms and clinical application of cilostazol.

11.
Medicine (Baltimore) ; 98(47): e18119, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31764852

RESUMO

RATIONALE: Uterine adenosarcoma (UA) with sarcomatous overgrowth (ASSO) is a rare and aggressive disease. Herein, wereported the case of a young patient with advanced uterine ASSO. PATIENTS CONCERNS: A 29-year-old woman with the diagnoses of endometrial polyp and adenomyosis underwent hysteroscopic endometrial polypectomy for the giant endometrial polyp. Postoperative regular ultrasound scan indicated thickened endometriumand an ill-defined mass with continuous enlargement in the myometrium of the posterior wall of the uterus, which was considered as an adenomyoma. Two years after hysteroscopy, she was re-admitted due to lower abdominal distension and large pelvic mass. At that time, she had taken oral short-acting contraceptives for 2.5 years. DIAGNOSES: Magnetic resonance imaging (MRI) of the pelvis revealed an irregular mass with the size of 12*56*107 mm in the right annex area, without distinct border with the rectum, moreover, an uneven intrauterine echo that has no obvious boundary with uterine wall. Right ovarian cancer and adenomyoma were initially considered. INTERVENTIONS: The patient received transperitoneal retroperitoneal pelvic combined with total viscera resection, including uterus, bilateral appendages and rectum, omentectomy, appendectomy, lymphadenectomy, and ileostomy. Postoperative pathology confirmed ASSO in the uterine cavity and muscular layer, the whole cervical duct and the right adnexal. She underwent 2 systemic chemotherapy sessions after the surgery. The chemotherapy regimen was ifosfamide 2.5 g day 1 to 3, with liposomal doxorubicin 40 mg day 1. OUTCOMES: The final diagnosis was uterine ASSO, International Federation of Gynecology and Obstetrics stage IVa. The patient has been following-up so far, with no progression. LESSONS: Review of the case indicated that history of long-term oral short-acting contraceptives and giant endometrial polyps may be the high-risk factors for UA. For patients with high-risk factors, the follow-up ultrasound scan should be more frequently conducted. Moreover, 3D-ultrasound, MRI and outpatient hysteroscopy are recommended for routine screening. Placement of levonorgestrel-releasing intra-uterine system after hysteroscopy may be an effective intervention for patients with a high risk of giant polyps. Cluster of Differentiation 10, Estrogen receptor, Progesterone receptor, and nuclear antigen may be predictors for prognosis and selection of individualized treatment program.

12.
Neurochem Res ; 44(12): 2786-2795, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31691883

RESUMO

The antinociceptive effects of spirocyclopiperazinium salt compound DXL-A-24 on neuropathic pain and chemical-stimulated pain were investigated in this study. After the administration of DXL-A-24, the paw withdrawal latency (PWL) and mechanical withdrawal threshold (MWT) were increased in rats suffering from neuropathic pain (chronic constriction injury, CCI) on days 1, 3, 5, 7 and 14 after surgery, and pain responses were inhibited in mice stimulated with chemicals (formalin or acetic acid). In the analysis of antinociceptive targets, the effect of DXL-A-24 was blocked by a peripheral nicotinic acetylcholine receptor (nAChR) antagonist (hexamethonium, Hex) or α7 nAChR antagonist (methyllycaconitine, MLA) in the formalin test. Meanwhile, the effect of DXL-A-24 was also blocked by a peripheral muscarinic acetylcholine receptor (mAChR) antagonist (atropine methylnitrate, Amn) or M4 mAChR antagonist (tropicamide, TRO). The antinociceptive signalling pathway was explored using molecular biology methods in ipsilateral dorsal root ganglions (DRGs) of CCI rats after the administration of DXL-A-24 for 7 days. Western blot analyses showed that the increased levels of phosphorylation of calcium/calmodulin-dependent protein kinase II alpha (CaMKIIα) and cAMP response element-binding protein (CREB) were eliminated, and the qRT-PCR assay showed that the increase in the expression of Tumor necrosis factor alpha (TNF-α) mRNA was reduced. Meanwhile, immunofluorescence staining revealed that the increase in calcitonin gene related peptide (CGRP) expression was inhibited by the administration of DXL-A-24, and the effect was blocked by MLA or TRO. In conclusion, DXL-A-24 exerts significant antinociceptive effects on neuropathic pain and chemical-stimulated pain. The antinociceptive effect of DXL-A-24 is probably attributed to the activation of peripheral α7 nAChR and M4 mAChR, the subsequent inhibition of the CaMKIIα/CREB signalling pathway, and finally the inhibition of TNF-α and CGRP expression.

13.
Clin Neurophysiol ; 131(1): 54-62, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31751840

RESUMO

OBJECTIVE: There is increasing evidence of cognitive impairment (CI) frequently occurring in patients with multiple system atrophy (MSA); however, the neurobiological mechanisms underlying CI in patients with MSA remain unclear. METHODS: We enrolled 61 patients with probable MSA and 33 healthy controls (HC). We used degree centrality (DC) analysis to assess changes in the centrality level of MSA-CI related brain nodes. We conducted a secondary seed-based functional connectivity (FC) analysis to investigate dysfunctions in cognitive networks related to MSA. Further, we analysed the correlation between clinical symptoms and acquired connectivity measures. RESULTS: Compared with HC, patients with MSA-CI and those with MSA with normal cognition (MSA-NCI) exhibited lower DC values in the left calcarine and right postcentral regions and higher DC values in the bilateral caudate and left precuneus. There were significant differences in the DC values in the right middle prefrontal gyrus between the MSA-CI and MSA-NCI groups. The mean DC values in the right middle prefrontal gyrus (RMPFG) were correlated with clinical cognitive severity. Consequently, we used this brain region as a seed in secondary seed-based FC analysis and observed FC changes within the right precuneus, inferior parietal lobe, and right insula. CONCLUSIONS: Decreased middle prefrontal cortex activity and its altered functional connectivity with the precuneus, inferior parietal lobe, and insula are possible biomarkers of cognitive dysfunction in patients with MSA-CI. SIGNIFICANCE: Cognitive impairment in MSA is associated with alterations in the dorsolateral prefrontal cortex network.

14.
Int J Surg ; 72: 206-213, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31734255

RESUMO

BACKGROUND: Long non-coding RNA metastasis-associated lung adenocarcinoma transcript 1 (lncRNA, MALAT1) has been found to be aberrantly expressed in osteosarcoma, while high MALAT1 expression is correlated with both metastasis and prognosis. This meta-analysis set out to investigate the prognostic value of lncRNA MALAT1 in patients living with osteosarcoma. METHODS: We conducted a systematical search of available databases from inception to May 2019. Odds ratios (OR) of clinical parameters, as well as hazard ratio (HR) of overall survival (OS), were calculated in order to evaluate the relationship between MALAT1 expression and the prognosis of patients living with osteosarcoma. RESULTS: Nine eligible studies which included a total of 599 osteosarcoma patients were enrolled in the present study. Pooled results found that high MALAT1 expression was associated with clinical stage and distant metastasis, but not age, gender, tumor anatomical location or tumor size. When compared to patients with low MALAT1 expression, patients with high MALAT1 expression were markedly correlated with a worse OS. Moreover, MALAT1 may be an independent predictive factor for OS in patients living with osteosarcoma. CONCLUSIONS: This meta-analysis suggests that high MALAT1 expression is associated with advanced clinicopathological features as well as unfavorable prognosis. LncRNA MALAT1 has the potential to serve as a moderate prognostic biomarker for osteosarcoma.

15.
Environ Res ; : 108863, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31699403

RESUMO

In order to enhance the productivity of methane from the waste activated sludge (WAS), a coupled system of microbial electrolysis cell (MEC) and anaerobic digestion (AD) was proposed. In this study, alkali, ultrasound-alkali, high-temperature coupled microaeration (TM) were applied as pretreatment methods to disintegrate the WAS flocs and break bacterial cell. After ultrasound-alkali pretreatment, the maximum accumulated concentration of VFAs and SCOD increased by 6.4 and 13.8 times compared with the initial concentration, which were 2.8 and 2.6 times of alkali pretreatment, and 2.1 and 2.1 times of TM pretreatment. Then, the pretreated sludge was transferred into MEC-AD coupled reactors and control group of AD reactors. The results showed that, methane production rate was enhanced to 0.15 m3 CH4/m3 reactor/d in the coupled reactors, which was improved by 3 times compared with control AD (0.05 m3 CH4/m3 reactor/d). The methane yield of MEC-AD coupled reactors achieved 808 ±â€¯8 mL, which were increased by 97.0% ±â€¯1.85% compared to control AD (410 mL). Using MEC can promote the rate of organics degradation and methane yield. The MEC-AD coupled system realized a good performance on the treatment of WAS and improved the efficiency of methane production.

16.
Reprod Fertil Dev ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31747535

RESUMO

Fibroblast growth factors (FGFs) play crucial roles in early gonadal development and germ cell maturation of mammals; FGF9 is involved in mammalian testis steroidogenesis. However, the upstream regulators of FGF9 in ovine testosterone biosynthesis remain unknown. Long non-coding RNAs (lncRNAs) are crucial regulators of multiple biological functions that act by altering gene expression. In the present study, we analysed the role of LOC105611671, a lncRNA upstream of FGF9, in Hu sheep steroidogenesis. We found that LOC105611671 expression increased significantly in Hu sheep testes during sexual maturation (P<0.05). Moreover, levels of FGF9 and testosterone were decreased by LOC105611671 knockdown in Hu sheep Leydig cells (LCs). Results of transient transfection and luciferase assays revealed that FGF9 is a functional target gene of oar-miR-26a in ovine LCs. Further functional validation experiments revealed that LOC105611671 regulates testosterone biosynthesis by targeting oar-miR-26a. Overall, the present study describes the expression profile of LOC105611671 during sexual maturation and demonstrates that LOC105611671 modulates FGF9 expression by targeting oar-miR-26a to promote testis steroidogenesis in Hu sheep. Our research provides a new theoretical basis for genetic and molecular research on testosterone biosynthesis in sheep.

17.
J Zhejiang Univ Sci B ; 20(12): 945-959, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31749342

RESUMO

BACKGROUND: The shortage of donor corneas is a severe global issue, and hence the development of corneal alternatives is imperative and urgent. Although attempts to produce artificial cornea substitutes by tissue engineering have made some positive progress, many problems remain that hamper their clinical application worldwide. For example, the curvature of tissue-engineered cornea substitutes cannot be designed to fit the bulbus oculi of patients. OBJECTIVE: To overcome these limitations, in this paper, we present a novel integrated three-dimensional (3D) bioprinting-based cornea substitute fabrication strategy to realize design, customized fabrication, and evaluation of multi-layer hollow structures with complicated surfaces. METHODS: The key rationale for this method is to combine digital light processing (DLP) and extrusion bioprinting into an integrated 3D cornea bioprinting system. A designable and personalized corneal substitute was designed based on mathematical modelling and a computer tomography scan of a natural cornea. The printed corneal substitute was evaluated based on biomechanical analysis, weight, structural integrity, and fit. RESULTS: The results revealed that the fabrication of high water content and highly transparent curved films with geometric features designed according to the natural human cornea can be achieved using a rapid, simple, and low-cost manufacturing process with a high repetition rate and quality. CONCLUSIONS: This study demonstrated the feasibility of customized design, analysis, and fabrication of a corneal substitute. The programmability of this method opens up the possibility of producing substitutes for other cornea-like shell structures with different scale and geometry features, such as the glomerulus, atrium, and oophoron.

18.
ACS Sens ; 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31736294

RESUMO

A digital fluorescence detector (DFD), a handheld fluorescence detection device, can convert the fluorescence signal of samples into the corresponding fluorescer concentration. Herein, by adopting a DFD as the readout, a novel intelligent platform was developed based on a ratiometric paper-based device (RPD) for multiple aminoglycoside detection. There are five layers and four parallel channels contained in the designed RPD, functioning as reagent storage, fluidic path control and signal processing, respectively. The rationale of this design lies in the fact that aptamer/graphitic carbon nitride nanosheet (Apt/g-C3N4 NS) modified layers can catalyze o-phenylenediamine to fluorescent 2,3-diaminophenazine (DAP) in the presence of H2O2. When Apt was removed from nanosheets via the Apt-target reaction, the peroxidase-like activity would be decreased, thus decreasing the production of DAP. All the changes of the fluorescence DAP signal can be read out using a portable DFD. Based on the DFD signal change related to the concentration of the target, a quantitative reaction platform was established. Furthermore, the sample flow and Apt-target reaction time can be reasonably regulated using the H2O2-cleavable hydrophobic compound modified layer placed between the target recognition region and detection region. Then, the practicality of this platform was verified through realizing sensitive analysis of streptomycin, tobramycin, and kanamycin simultaneously. Overall, with merits including portability and ease of operation, the platform shows great potential in on-site simultaneous detection of multiple targets, especially in resource-limited settings.

19.
Mar Drugs ; 17(12)2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31766406

RESUMO

A pair of stereoisomers possessing novel structures with 6/6/5 fused-ring systems, neo-debromoaplysiatoxin E (1) and neo-debromoaplysiatoxin F (2), were isolated from the marine cyanobacterium Lyngbya sp. Their structures were elucidated using various spectroscopic techniques including high resolution electrospray ionization mass spectroscopy (HRESIMS) and nuclear magnetic resonance (NMR). The absolute stereochemistry was determined by calculated electronic circular dichroism (ECD) and gauge-independent atomic orbital (GIAO) NMR shift calculation followed by DP4+ analysis. Significantly, this is the first report on aplysiatoxin derivatives with different absolute configurations at C9-C12 (1: 9S, 10R, 11S, 12S; 2: 9R, 10S, 11R, 12R). Compounds 1 and 2 exhibited potent blocking activities against Kv1.5 with IC50 values of 1.22 ± 0.22 µM and 2.85 ± 0.29 µM, respectively.

20.
Int J Mol Sci ; 20(20)2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31635221

RESUMO

The complement 1q binding protein C (C1QBP), also known as p32, is highly expressed in rapidly growing tissues and plays a crucial role in cell proliferation and apoptosis. However, there are no data interpreting its mechanisms in muscle development. To investigate the role of p32 in sheep muscle development, an 856 bp cDNA fragment of p32 containing an 837 bp coding sequence that encodes 278 amino acids was analyzed. We then revealed that the expression of p32 in the longissimus and quadricep muscles of fetal sheep was more significantly up-regulated than expression at other developmental stages. Furthermore, we found that the expression of p32 was increased during myoblasts differentiation in vitro. Additionally, the knockdown of p32 in sheep myoblasts effectively inhibited myoblast differentiation, proliferation, and promoted cell apoptosis in vitro. The interference of p32 also changed the energy metabolism from Oxidative Phosphorylation (OXPHOS) to glycolysis and activated AMP-activated protein kinase (AMPK) phosphorylation in sheep myoblasts in vitro. Taken together, our data suggest that p32 plays a vital role in the development of sheep muscle and provides a potential direction for future research on muscle development and some muscle diseases.

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