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1.
J Cell Physiol ; 235(1): 429-441, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31230364

RESUMO

Colorectal cancer (CRC) is still a fatal health problem around the world. The underlying mechanisms of CRC have not been fully elucidated. N-myc interactor (NMI) acts as an oncogene or a tumor-suppressor gene in several kinds of cancers but CRC. Here, the expression of NMI was found higher in CRC tissues and cells. Higher expression of NMI indicated the poorer prognosis of CRC patients. Moreover, the proliferation of CRC cells was suppressed significantly after we silenced the expression of NMI, while overexpression of NMI promoted CRC cell proliferation. Flow cytometry demonstrated that NMI promoted cell proliferation through facilitating cell transition from the G1 phase to the S phase. Furthermore, it was found that NMI suppressed the phosphorylation of Smad3 by upregulating the expression of STAT1. The effect of NMI depletion on cell proliferation could be reversed by using Smad3 inhibitor SIS3. In summary, our findings demonstrated that NMI promoted cell proliferation via TGFß/Smad pathway and could indicate the prognosis of patients with CRC.

2.
Carbohydr Polym ; 227: 115368, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31590842

RESUMO

This paper reveals the structural variations of cellulose nanocrystals (CNC) prepared from sugarcane bagasse (SCB) using different methods and the organic-inorganic hybrid nanomaterials were constructed with polyhedral oligomeric silsesquioxane (POSS). First, pure cellulose was extracted from SCB, and four CNCs were successfully obtained. The huge differences in structure and properties provide a choice for various applications. Subsequently, novel CNC/POSS hybrid nanomaterials were prepared from carboxylated CNC via carbodiimide-assisted coupling chemistry. The morphology and properties of hybrids were investigated in detail. The hybrids exhibit great differences in structure and properties due to the difference in CNC. The incorporation of POSS has improved the thermal performance of the CNC, and the mass ratio has a significant impact on molecular structure. This work provides useful information for the preparation of multi-type CNCs using agricultural and forestry by-products, and the novel CNC/POSS hybrid has opened up new ideas for the application of nanocellulose.

3.
J Ethnopharmacol ; 247: 112201, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31499140

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Bergenin is a well-known active compound that exhibits antioxidant, antiarrhythmic, hepatoprotective, and anti-inflammatory activities. However, the resource reserve of Rodgersia sambucifolia, one of the main raw materials for extracting bergenin, have sharply declined, and the bergenin content in different germplasms differs vastly, resulting in a serious shortage of the market supply of bergenin. AIM OF THE STUDY: To investigate the influence of genetic diversity and environmental factors on bergenin content in Rodgersia sambucifolia. MATERIALS AND METHODS: Fifty Rodgersia sambucifolia samples with a growth period of 2-3 years were collected from different areas across China and the bergenin content was determined via HPLC. Meanwhile the total genomic DNA was extracted and ISSR was performed. The bergenin content as measured using HPLC and the environmental data gathered from the meteorological stations and field work were combined and analyzed using correlation tests in XLSTAT 2018 to detect the key factors affecting bergenin content. The genetic UPGMA tree constructed based on genetic distances of the 50 samples and the chemical dendrogram constructed according to the distance between the bergenin content were compared to determine the correlation between genetic and chemical differentiation. RESULTS: Among the 50 individuals, bergenin content varied from 2.83 to 12.54%, with the highest content being 4.43-fold that of the lowest content. The survey of the 50 individuals produced a total of 193 amplified bands, 187 of which were polymorphic (96.89%). In the study, bergenin content was positively correlated with annual mean temperature (AMT) (r = 0.583, P < 0.0001) and 1-12 month monthly mean temperature (MMT) (P < 0.0001). A comparison of the genetic dendrogram with the AHC dendrogram found no corresponding relationship between them. Mantel correlation analyses also showed that there was no significant correlation between them (r = 0.144). CONCLUSIONS: There were large differences in bergenin content among different germplasms that were not correlated with the high genetic variation in Rodgersia sambucifolia but were significantly correlated with environmental factors, such as temperature. This study lays the foundation for subsequent superior germplasm selection and artificial breeding of Rodgersia sambucifolia to improve the bergenin content and meet market demands.

4.
IEEE Trans Vis Comput Graph ; 26(1): 270-279, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31425099

RESUMO

Asymmetric tensor fields have found applications in many science and engineering domains, such as fluid dynamics. Recent advances in the visualization and analysis of 2D asymmetric tensor fields focus on pointwise analysis of the tensor field and effective visualization metaphors such as colors, glyphs, and hyperstreamlines. In this paper, we provide a novel multi-scale topological analysis framework for asymmetric tensor fields on surfaces. Our multi-scale framework is based on the notions of eigenvalue and eigenvector graphs. At the core of our framework are the identification of atomic operations that modify the graphs and the scale definition that guides the order in which the graphs are simplified to enable clarity and focus for the visualization of topological analysis on data of different sizes. We also provide efficient algorithms to realize these operations. Furthermore, we provide physical interpretation of these graphs. To demonstrate the utility of our system, we apply our multi-scale analysis to data in computational fluid dynamics.

5.
Waste Manag ; 101: 116-125, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31610473

RESUMO

Based on the theory of planned behavior (TPB), this article analyses how conscientiousness and risk perception influence consumers' behavior intentions in regard to smartphone recycling. We carried out field research in Anhui Province, China and collected 802 valid questionnaires as basic data for this study. The empirical results of structural equation model (SEM) indicate that conscientiousness is positively related to attitude, subjective norm, and perceived behavioral control towards smartphone recycling, while attitude, subjective norm, and past behavior are positively related to smartphone recycling intention. Attitude and subjective norm mediate the relationship between conscientiousness and smartphone recycling intention. In addition, we found that risk perception moderates the relationships between conscientiousness and attitude, subjective norm, perceived behavioral control, and past behavior. Theoretical and practical implications, limitations of the study, and future directions are discussed.


Assuntos
Smartphone , Atitude , China , Intenção , Teoria Psicológica , Inquéritos e Questionários
6.
J Colloid Interface Sci ; 559: 13-20, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31606523

RESUMO

Severe "Shuttle effect" and uncontrollable lithium-dendrite growth are ongoing challenges that hinder the practical application of Lithium-sulfur (Li-S) batteries. Herein, a bifunctional separator was modified by Al2O3 and carbon nanotubes (CNTs) via a facile method. Li-S battery assembled with the modified separator shows excellent cycling stability (760.4 mA h g-1 at 0.2 C after 100 cycles) and promising rate performance. The reason is ascribed to synergistic effect of CNTs and Al2O3 double coating layers, the strong physicochemical interaction between Al2O3 and the polysulfides could alleviate the shuttle effect, and the high conductivity of CNTs can facilitate the reaction kinetics of sulfur and its corresponding discharge products, respectively, which can improve the utilization ratio of sulfur. In addition, the double protection layers improve the hardness of the separator, as well as regulate Li+ ion deposition, which can effectively prevent the formation of lithium dendrites, thus the safety of the batteries are significant improved.

7.
Biomaterials ; 228: 119575, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31677394

RESUMO

The treatment of pulmonary infections with antibiotics administered via pulmonary delivery provides for higher local therapeutic efficacy rather than through systemic administration. Pneumonia is globally considered a major cause of death due to a lack of proper medication. The treatment of pneumonia with inhalable antibiotics (such as azithromycin (AZM)) can provide a maximum pulmonary therapeutic effect without significant systemic side effects. Compared to non-effervescent microparticles, effervescent microparticles can provide an active driving force to release loaded antibiotics for subsequent distribution deep into the lung by virtue of its smaller size. In this study, N-fumaroylated diketopiperazine (FDKP) was used as a carrier to prepare effervescent inhalable microparticles loaded with AZM (AZM@FDKP-E-MPs). This effervescent dry powder was characterized for both in vitro and in vivo deposition in the lung and the results obtained showed significant improvement in lung deposition and anti-bacterial efficiency, suggesting a strong potential application for pneumonia treatment.

8.
Enzyme Microb Technol ; 132: 109408, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31731973

RESUMO

Lipase ZC12, a cold-adapted lipase derived from Psychrobacter sp. ZY124, can be effectively activated by Ca2+. Inspired by this significant property, we developed a novel immobilized lipase ZC12/Ca3(PO4)2 hybrid nanoflowers (LHNs). The LHNs have been characterized as a regular hierarchical flowerlike structure nanoflowers by scanning electron microscopy (SEM). Compared with free lipase ZC12, the LHNs exerted enhanced enzymatic activity of 206% and 2.31-fold in kcat/Km value, especially high specific activity at low temperature. After 7 successive cycles, the LHNs could still maintain its initial activity, demonstrating superior durability than the free lipase ZC12. Meanwhile, its stability basically kept unchanged in a wide range of temperature and pH. Finally, fructose laurate was transformed by the LHNs with 57.39% conversion rate which is twice as much as the free lipase. To sum up, these results validated that LHNs could emerge as an efficient immobilized lipase and possess the promising potential for practical applications.

9.
Gene ; 724: 144146, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31634561

RESUMO

miRNA mediated genetic regulation is widely involved in carcinogenesis of cervical cancer. In this study, miR-214 was confirmed to directly regulate MKK3 via imperfect base-pairing to its 3'UTR, resulting down-regulation of its expression level. Compared to normal tissues, a down-regulated level of miR-214 was observed in cervical cancer, while MKK3 was up-regulated. Next, we demonstrated that over-expression of miR-214 or knockdown of MKK3 can inhibit the growth, proliferation, invasion and migration of cervical cancer in vitro and in vivo. Moreover, the effects of miR-214 in HeLa cells were rescued by the restoration of MKK3. In conclusion, our results laid new foundations for investigating the pathogenesis and diagnosis of cervical cancer.

10.
Nanotechnology ; 31(3): 035601, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31574488

RESUMO

Monolayer MoS2 in triangular configurations with rich edges or high-quality uniform films are either catalytically active for the hydrogen evolution reaction or flexible for functional electronic and optoelectronic devices. Here, we have experimentally discovered that these two types of MoS2 products can be selectively synthesized on graphene or sapphire substrates, which are associated with both different adsorption energy and diffusion-energy barrier for vapor precursors during growth. Our study not only provides insights into the on-surface synthesis of high-quality MoS2 monolayers, but also can be applied to the growth of vertically-stacked and large-scale in-plane lateral MoS2-graphene heterostructures.

11.
Clin Infect Dis ; 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31673709

RESUMO

BACKGROUND: Antimicrobial stewards may benefit from comparative data to inform interventions that promote optimal antimicrobial use in the inpatient setting. METHODS: Antimicrobial stewards from eight geographically dispersed Veterans Affairs (VA) inpatient facilities participated in the development of iterative antimicrobial use visualization tools that allowed for comparison to facilities of similar complexity. The visualization tools consisted of an interactive web-based antimicrobial dashboard and, later, a standardized antimicrobial usage report updated at user-selected intervals. Following tool implementation, stewards participated in monthly learning collaboratives. The percent change in average monthly antimicrobial use [all antimicrobial agents, anti-methicillin-resistant Staphylococcus aureus agents (anti-MRSA), and anti-pseudomonal agents] was analyzed using a pre-post (1/2014-1/2016 versus 7/2016-1/2018) design with segmented regression and external comparison with uninvolved control facilities (n=118). RESULTS: Intervention sites demonstrated a 2.1% decrease (95% confidence interval (CI) [-5.7%, 1.6%]) in total antimicrobial use pre-post intervention, versus a 2.5% increase (95% CI [0.8%, 4.1%]) in non-intervention sites (absolute difference 4.6%, P=0.025). Anti-MRSA antimicrobial use decreased 11.3% (95% CI [-16.0%, -6.3%]) at intervention sites versus a 6.6% decrease (95% CI [-9.1%, -3.9%]) at non-intervention sites (absolute difference 4.7%, P=0.092). Anti-pseudomonal antimicrobial use decreased 3.4% (95% CI [-8.2%, 1.7%]) at intervention sites versus a 3.4% increase (95% CI [0.8%, 6.5%]) at non-intervention sites (absolute difference 7.0%, P=0.018). CONCLUSIONS: Comparative data visualization tool use by stewards in a pilot implementation project at eight VA facilities was associated with significant reductions in overall antimicrobial and anti-pseudomonal use relative to uninvolved facilities.

12.
Water Res ; 169: 115210, 2019 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-31670084

RESUMO

Developing efficient sunlight photocatalysts with enhanced photocorrosion resistance and minimal ecotoxicological effects on aquatic biota is critical to combat water contamination. Here, the role of chemical composition, architecture, and fixation on the ecotoxicological effects on microalgae of different ZnO and ZnO@ZnS based water decontamination photocatalysts was analyzed in depth. In particular, the ecotoxicological effects of films, nanoparticles and biomimetic micro/nano-ferns were carefully assessed by correlating the algae's viability to the Zn(II) release, the photocatalyst-microalgae interaction, and the production of reactive oxygen species (ROS). The results showed a drastic improvement in algal viability for supported ZnO@ZnS core@shell micro/nanoferns, as their ecotoxicity after 96 h light exposure was significantly lower (3.7-10.0% viability loss) compared to the ZnO films (18.4-35.5% loss), ZnO micro/nanoferns (28.5-53.5% loss), ZnO nanoparticles (48.3-91.7% loss) or ZnO@ZnS nanoparticles (8.6-19.2% loss) for catalysts concentrations ranging from 25 mg L-1 to 400 mg L-1. In particular, the ZnO@ZnS micro/nanoferns with a concentration of 400 mg L-1 exhibited excellent photocatalytic efficiency to mineralize a multi-pollutant solution (81.4 ±â€¯0.3% mineralization efficiency after 210 min under UV-filtered visible light irradiation) and minimal photocorrosion (<5% of photocatalyst dissolution after 96 h of UV-filtered visible light irradiation). Remarkably, the ZnO@ZnS micro/nanoferns showed lower loss of algal viability (9.8 ±â€¯1.1%) after 96 h of light exposure, with minimal reduction in microalgal biomass (9.1 ±â€¯1.0%), as well as in the quantity of chlorophyll-a (9.5 ±â€¯1.0%), carotenoids (8.6 ±â€¯0.9%) and phycocyanin (5.6 ±â€¯0.6%). Altogether, the optimized ZnO@ZnS core@shell micro/nanoferns represent excellent ecofriendly photocatalysts for water remediation in complex media, as they combine enhanced sunlight remediation efficiency, minimal adverse effects on biological microorganisms, high reusability and easy recyclability.

13.
Nature ; 575(7784): 679-682, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31723262

RESUMO

Caspase-8 is a protease with both pro-death and pro-survival functions: it mediates apoptosis induced by death receptors such as TNFR11, and suppresses necroptosis mediated by the kinase RIPK3 and the pseudokinase MLKL2-4. Mice that lack caspase-8 display MLKL-dependent embryonic lethality4, as do mice that express catalytically inactive CASP8(C362A)5. Casp8C362A/C362AMlkl-/- mice die during the perinatal period5, whereas Casp8-/-Mlkl-/- mice are viable4, which indicates that inactive caspase-8 also has a pro-death scaffolding function. Here we show that mutant CASP8(C362A) induces the formation of ASC (also known as PYCARD) specks, and caspase-1-dependent cleavage of GSDMD and caspases 3 and 7 in MLKL-deficient mouse intestines around embryonic day 18. Caspase-1 and its adaptor ASC contributed to the perinatal lethal phenotype because a number of Casp8C362A/C362AMlkl-/-Casp1-/- and Casp8C362A/C362AMlkl-/-Asc-/- mice survived beyond weaning. Transfection studies suggest that inactive caspase-8 adopts a distinct conformation to active caspase-8, enabling its prodomain to engage ASC. Upregulation of the lipopolysaccharide sensor caspase-11 in the intestines of both Casp8C362A/C362AMlkl-/- and Casp8C362A/C362AMlkl-/-Casp1-/- mice also contributed to lethality because Casp8C362A/C362AMlkl-/-Casp1-/-Casp11-/- (Casp11 is also known as Casp4) neonates survived more often than Casp8C362A/C362AMlkl-/-Casp1-/- neonates. Finally, Casp8C362A/C362ARipk3-/-Casp1-/-Casp11-/- mice survived longer than Casp8C362A/C362AMlkl-/-Casp1-/-Casp11-/- mice, indicating that a necroptosis-independent function of RIPK3 also contributes to lethality. Thus, unanticipated plasticity in death pathways is revealed when caspase-8-dependent apoptosis and MLKL-dependent necroptosis are inhibited.

14.
Theor Appl Genet ; 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31773176

RESUMO

KEY MESSAGE: Two novel midge resistance QTL were mapped to a 4.9-Mb interval on chromosome arm 4AL based on the genetic maps constructed with SNP markers. Orange wheat blossom midge (OWBM) is a devastating insect pest affecting wheat production. In order to detect OWBM resistance genes and quantitative trait loci (QTL) for wheat breeding, two recombinant inbred line (RIL) populations were established and used for molecular mapping. A total of seven QTL were detected on chromosomes 2D, 4A, 4D and 7D, respectively, of which positive alleles were all from the resistant parents except for the QTL on 7D. Two stable QTL (QSm.hbau-4A.2-1 and QSm.hbau-4A.2-2) were detected in both populations with the LOD scores ranging from 5.58 to 29.22 under all three environments, and they explained a combined phenotypic variation of 24.4-44.8%. These two novel QTL were mapped to a 4.9-Mb physical interval. The single-nucleotide polymorphism (SNP) markers AX-109543456, AX-108942696 and AX-110928325 were closely linked to the QTL and could be used for marker-assisted selection (MAS) for OWBM resistance in wheat breeding programs.

15.
Immunol Res ; 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31773490

RESUMO

Limited protective effects of commercially available vaccines necessitate the development of novel pneumococcal vaccines. We recently reported a pneumococcal systemic vaccine containing two proteins, Pneumococcal surface protein A (PspA of family 1 and 2) and a bacterium-like particle-based pneumococcal mucosal vaccine containing PspA2 and PspA4 fragments, both eliciting broad protective immune responses. We had previously reported that subcutaneous (s.c.+s.c.+s.c.) immunization with the systemic vaccine induced more pronounced humoral serum IgG responses, while intranasal (i.n.+i.n.+i.n.) immunization with the mucosal vaccine elicited a more pronounced mucosal secretory IgA (sIgA) response. We hypothesized that a combinatorial administration of the two vaccines might elicit more pronounced and broader protective immune responses. Therefore, this study aimed to determine the efficacy of combinatorial prime-boost immunization using both systemic and mucosal vaccines for a pneumococcal infection. Combinatorial prime-boost immunization (s.c.+i.n. and i.n.+s.c.) induced not only IgG, but also mucosal sIgA production at high levels. Systemic priming and mucosal boosting immunization (s.c.+i.n.) provided markedly better protection than homologous prime-boost immunization (s.c.+s.c.+s.c. and i.n.+i.n.+i.n.). Moreover, it induced more robust Th1 and Th17 cell-mediated immune responses than mucosal priming and systemic boosting immunization (i.n.+s.c.). These results indicate that combinatorial prime-boost immunization potentially induces a robust systemic and mucosal immune response, making it an optimal alternative for maximum protection against lethal pneumococcal infections.

16.
Zhen Ci Yan Jiu ; 44(11): 858-9, 2019 Nov 25.
Artigo em Chinês | MEDLINE | ID: mdl-31777239

RESUMO

In the present paper, we introduce a newly modified device named "transcutaneous electrical auricular concha stimulator (TEACS)" for rats. It concludes a main unit (power and control buttons) with newly designed specific output electrodes. Each of the output electrode is made up of two pieces of iron sheet containing magnet and can be firmly attached to the auricular concha and the corresponding site of dorsal auricle, respectively. The two iron sheets are separately connected to each of the output terminal of the main unit via two pieces of wire. This newly modified output electrode replaces the original wire clip, and solves the problems of easy loosening and easy injury of the original spring clip due to repeated usage, being simple, flexible and convenient in application.

17.
Artigo em Inglês | MEDLINE | ID: mdl-31749001

RESUMO

Triclosan (TCS) is a chlorophenol which is highly bacteriostatic and used in a wide array of consumer products. TCS is now one of the most commonly detected organic pollutants in the sewage sludges. The sludge utilization for fertilizers on agricultural land would pose the risk of causing adverse effects on plant growth and yield by TCS. However, the toxicity of TCS toward plants is comparatively less understood. In this study, we assessed the effects of TCS on tobacco plants which were grown in MS medium or soils containing various concentrations of TCS. Our results indicated that TCS at the concentration of 2 mg/L could strongly inhibit the tobacco seed germination. TCS could suppress tobacco plant growth in soil with different concentrations (10, 20, and 50 mg/kg) of TCS through the downregulation of chlorophyll contents, restricting photosynthesis and increasing generation of reactive oxygen species (ROS). Salicylic acid (SA) plays important roles in the stress response of plants. The role of exogenous SA application in protecting tobacco plants from TCS stress was also investigated in this study. SA application could significantly increase net photosynthesis, enhance antioxidant enzyme activity, and thereby enhancing tobacco plant tolerance to TCS. Moreover, the activation of MPK3 and MPK6 induced by TCS was downregulated in plants with the treatment of SA. It was thus referred that mitogen-activated protein kinases (MAPKs) might play a key role in the signal transduction of TCS stress, and this process might be regulated by SA signaling. Overall, our results demonstrated that TCS had negative impacts on tobacco plants and SA played a protective role on tobacco plants against TCS stress.

18.
Sensors (Basel) ; 19(22)2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31752410

RESUMO

Low altitude, small radar cross-section (RCS), and slow speed (LSS) targets, for example small unmanned aerial vehicles (UAVs), have become increasingly significant. In this paper, we propose a new automatic target recognition (ATR) system and a complete ATR chain based on multi-dimensional features and multi-layer classifier system using L-band holographic staring radar. We consider all steps of the processing required to make a classification decision out of the raw radar data, mainly including preprocessing for the raw measured Doppler data including regularization and main frequency alignment, selection, and extraction of effective features in three dimensions of RCS, micro-Doppler, and motion, and multi-layer classifier system design. We design creatively a multi-layer classifier system based on directed acyclic graph. Helicopters, small fixed-wing, and rotary-wing UAVs, as well as birds are considered for classification, and the measured data collected by L-band radar demonstrates the effectiveness of the proposed complete ATR classification system. The results show that the ATR classification system based on multi-dimensional features and k-nearest neighbors (KNN) classifier is the best, compared with support vector machine (SVM) and back propagation (BP) neural networks, providing the capability of correct classification with a probability of around 97.62%.

19.
Microsc Microanal ; : 1-9, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31753050

RESUMO

The seminiferous tubule (ST) is the location of spermatogenesis, where mature spermatozoa are produced with the assistance of Sertoli cells. The role of extracellular vesicles in the direct communication between Sertoli-germ cells in the ST is still not fully understood. In this study, we reported multivesicular bodies (MVBs) and their source of CD63-enriched exosomes by light and ultrastructure microscopy during the reproductive phases of turtles. Strong CD63 immunopositivity was detected at the basal region in the early and luminal regions of the ST during late spermatogenesis by immunohistochemistry (IHC), immunofluorescence (IF), and western blot (WB) analysis. Labeling of CD63 was detected in the Sertoli cell cytoplasmic processes that surround the developing germ cells during early spermatogenesis and in the lumen of the ST with elongated spermatids during late spermatogenesis. Furthermore, ultrastructure analysis confirmed the existence of numerous MVBs in the Sertoli cell prolongations that surround the round and primary spermatogonia during acrosome biogenesis and with the embedded heads of spermatids in the cytoplasm of Sertoli cells. Additionally, in spermatids, Chrysanthemum flower centers (CFCs) generated isolated membranes involved in MVBs and autophagosome formation, and their fusion to form amphiosomes was also observed. Additionally, autophagy inhibition by 3-methyladenine (after 24 h) increased CD63 protein signals during late spermatogenesis, as detected by IF and WB. Collectively, our study found MVBs and CD63 rich exosomes within the Sertoli cells and their response to autophagy inhibition in the ST during the spermatogenesis in the turtle.

20.
AAPS PharmSciTech ; 21(1): 6, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31754916

RESUMO

The aim of the study is to investigate the feasibility of fabricating FDM 3D-printed gastric floating tablets with low infill percentages and the effect of infill percentage on the properties of gastric floating tablets in vitro. Propranolol hydrochloride was selected as a model drug, and drug-loaded polyvinyl alcohol (PVA) filaments were produced by hot melt extrusion (HME). Ellipsoid-shaped gastric floating tablets with low infill percentage of 15% and 25% (namely E-15 and E-25) were then prepared respectively by feeding the extruded filaments to FDM 3D printer. Thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray powder diffraction (XRD), and scanning electron microscopy (SEM) were employed to characterize the filaments and 3D-printed tablets, and a series of evaluations were performed to the 3D-printed tablets, including the weight variation, drug content, hardness, in vitro floating behavior, and drug release of the tablets. The SEM results showed that the drug-loaded filaments and 3D-printed tablets appeared intact without defects, and the printed tablets were composed of filaments deposited uniformly layer by layer. The model drug and the excipients were thermally stable under the process temperature of extruding and printing, with a small amount of drug crystals dispersing in the drug-loaded filaments and 3D-printed tablets. Both E-15 and E-25 could float on artificial gastric fluids without any lag time and released in a sustained manner. Compared with E-15, the E-25 presented less weight variation, higher tablet hardness, shorter floating time, and longer drug release time.

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