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1.
Front Microbiol ; 14: 1238376, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37822745

RESUMO

Zoonotic parasites pose significant health risks globally. In the present study, we combined a microfluidic chip with loop-mediated isothermal amplification (on-chip LAMP) to detect five zoonotic parasites: Toxoplasma gondii, Cryptosporidium parvum, Cryptosporidium hominis, Clonorchis sinensis, and Taenia solium. This method enabled the simultaneous parallel analysis of five genetic markers from a maximum of four samples per chip. The on-chip LAMP assay was conducted in a highly automated format via the addition (by pipetting) of each sample in a single operation. The reaction was performed in volumes as low as 5 µL at a temperature of 65°C for 60 min, achieving limits of detection ranging from 10-2 to 10-3 pg./µL of recombinant plasmid DNA. All the time-to-positive values were less than 40 min, and almost all the coefficients of variation were less than 10%, even when using limit of detection concentrations for multiple pathogens, indicating robust reproducibility among replicates. The clinical sensitivity and specificity for detecting 135 field samples were 98.08 and 97.59%, respectively, compared with traditional biological methods, indicating good applicability in the detection of field samples. This on-chip LAMP assay allows for low reagent consumption, ease of operation, and multiple analyses of samples and genetic targets, and is applicable for on-site detection and the routine monitoring of multiple zoonotic parasites.

2.
Sci Adv ; 9(37): eadi9108, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37713481

RESUMO

Normally, stirring is regarded as a technology to disperse the substances in liquid evenly. However, Einstein's tea leaf paradox (ETLP) describes the phenomenon that tea leaves concentrate in a "doughnut" shape via a secondary flow effect while stirring. Herein, to demonstrate ETLP-induced concentration in nanofluid, we simulated the nanoparticle trajectory under stirring and made a grayscale analysis of SiO2 nanofluids during stirring and standing processes. Unexpectedly, a localized concentration effect in the layer flow was found beside the macroscopic ETLP effect. Subsequently, the localized concentration was applied to achieve the ultrafast aggregation of Au nanoparticles to form gold aerogels (GAs). The skeleton size of GAs was adjusted from about 10 to 200 nm by only adjusting the temperature of HAuCl4 solution. The fabricated GAs had extremely high purity and crystallinity, revealing potential applications in photocatalysis and surface-enhanced Raman scattering.

3.
J Cosmet Dermatol ; 22(4): 1327-1333, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36575876

RESUMO

BACKGROUND: Although the role of platelet-rich plasma (PRP) in ultraviolet light B (UVB)-induced photoaging has been confirmed in many studies, the specific mechanism is still not clear. Therefore, we attempted to investigate the effect and mechanism of PRP on UVB-induced human keratinocyte (HaCaT cells) apoptosis. METHODS: HaCaT cells were collected to construct UVB-induced photoaging models. Then, the cells were divided into Sham group, 5% PRP group, UVB group, and UVB + 5% PRP group. Next, MTT assay was used to detect the level of cell proliferation; flow cytometry to check the level of apoptosis; ELISA to determine the TNF-α, IL-18, IL-6, and IL-1ß levels in the supernatant; and Western blot to test Bax, Bcl-2, cytochrome c (Cyt.c), GRP78, CHOP, and ATF4 protein expression levels. RESULTS: Briefly, 5% PRP intervention could relieve the inhibition of UVB on HaCaT cell proliferation, inhibit the promotion of UVB to cell apoptosis, up-regulate UVB-induced Bcl-2 protein expression, and decrease Bax and Cyt.c protein level. In addition, 5% PRP significantly down-regulated the inflammatory factor levels of TNF-α, IL-18, IL-6, and IL-1ßin UVB-induced cells and reduced the inflammatory response. Moreover, 5% PRP also greatly reduced the protein expression levels of GRP78, CHOP, and ATF4 in UVB-induced cells and alleviated endoplasmic reticulum (ER) stress. CONCLUSION: PRP may protect HaCaT cells from UVB-induced apoptosis by alleviating inflammatory response and ER stress.


Assuntos
Interleucina-18 , Plasma Rico em Plaquetas , Humanos , Interleucina-18/metabolismo , Interleucina-18/farmacologia , Chaperona BiP do Retículo Endoplasmático , Raios Ultravioleta/efeitos adversos , Interleucina-6/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Proteína X Associada a bcl-2/metabolismo , Proteína X Associada a bcl-2/farmacologia , Queratinócitos/metabolismo , Apoptose , Estresse do Retículo Endoplasmático
4.
Gels ; 8(9)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36135256

RESUMO

Resveratrol (Res) is a plant extract with strong anti-inflammatory, antioxidant and anti-aging biological activities. However, Res is limited by its disadvantages, such as poor solubility, rapid metabolism and low bioavailability. In this study, the Resveratrol-loaded TEMPO-oxidized cellulose aerogel (RLTA) drug delivery system was prepared by the method of "dissolution-freeze-drying" and characterized by a series of analysis. Then the blood biochemical indexes and HE staining were measured and analyzed in animal experiments. The in vivo results showed that RLTA can decrease the levels of TNF-α and IL-6 inflammatory factors in the synovial fluid. Furthermore, the molecular mechanism was investigated through the analysis of silent information regulator 2 homolog 1 (Sirt1) protein expression, which suggested that RLTA could upregulate the expression of Sirt1 and mediate the P38 signaling pathway, thereby inhibiting the expression of COX-2 and MMP13 which can suppress the levels of IL-6 and TNF-α inflammatory factor. These results reveal that cellulose aerogel is a promising candidate for drug delivery and RLTA has great potential application for the treatment of sports osteoarthritis.

5.
Front Chem ; 10: 943902, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35844655

RESUMO

2D ZnO is one of the most attractive materials for potential applications in photocatalysis, gas and light detection, ultraviolet light-emitting diodes, resistive memory, and pressure-sensitive devices. The electronic structures, magnetic properties, and optical properties of M (Li, Na, Mg, Ca, or Ga) and TM (Cr, Co, Cu, Ag, or Au) adsorbed g-ZnO were investigated with density functional theory (DFT). It is found that the band structure, charge density difference, electron spin density, work function, and absorption spectrum of g-ZnO can be tuned by adsorbing M or TM atoms. More specifically, the specific charge transfer occurs between g-ZnO and adsorbed atom, indicating the formation of a covalent bond. The work functions of M adsorbed g-ZnO systems are obviously smaller than that of intrinsic g-ZnO, implying great potential in high-efficiency field emission devices. The Li, Na, Mg, Ca, Ga, Ag, or Au adsorbed g-ZnO systems, the Cr adsorbed g-ZnO system, and the Co or Cu adsorbed g-ZnO systems exhibit non-magnetic semiconductor proprieties, magnetic semiconductor proprieties, and magnetic metal proprieties, respectively. In addition, the magnetic moments of Cr, Co, or Cu adsorbed g-ZnO systems are 4 µ B, 3 µ B, or 1 µ B, respectively, which are mainly derived from adsorbed atoms, suggesting potential applications in nano-scale spintronics devices. Compared with the TM absorbed g-ZnO systems, the M adsorbed g-ZnO systems have more obvious absorption peaks for visible light, particularly for Mg or Ca adsorbed g-ZnO systems. Their absorption peaks appear in the near-infrared region, suggesting great potential in solar photocatalysis. Our work contributes to the design and fabrication of high-efficiency field emission devices, nano-scale spintronics devices, and visible-light responsive photocatalytic materials.

6.
ACS Appl Mater Interfaces ; 14(8): 10257-10266, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35170310

RESUMO

Solar steam generation has become a hot research topic because of its great potential to alleviate the drinking water crisis without extra energy input. Although some efforts focusing on designing spatial geometry have been made to multiply the evaporation performances of up-to-date three-dimensional evaporators, they still have some shortcomings, such as low material and space utilization efficiencies, complex spatial geometry, energy loss due to the hot solar absorption surface, and salt crystallization due to inefficient water supply. Herein, a biomimetic copper-based metal-organic framework (Cu-Cu(OH)2-MOF) foam sheet with interconnected pores and pine needle-like hierarchical structures consisting of Cu(OH)2 nanowires and MOF nanowhiskers is fabricated. The pine needle-like hierarchical structures of Cu-Cu(OH)2-MOF foam contribute to absorbing solar energy and supplying sufficient water by trapping incident light and enhancing the capillary force, respectively. Inspired by drying clothes outside under solar irradiation, through exposing one end of the Cu-Cu(OH)2-MOF foam to air, the biface evaporator achieves a subambient evaporation surface temperature and an evaporation rate of up to 3.27 kg m-2 h-1 under only one sun illumination. Furthermore, when coupled with an air flow, the biface evaporator realizes an excellent evaporation rate of 11.58 kg m-2 h-1 with an energy efficiency of 160.07% even in seawater, ensuring its great application prospect to be used in drinking water production and seawater desalination.

7.
J Burn Care Res ; 43(1): 263-268, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33970255

RESUMO

To investigate the effects of autologous platelet-rich plasma (PRP) on burn wound and burn pain in rats. Rats were treated with high-temperature copper rod to induce skin burn. During treatment, the wound area of rats was recorded on days 0, 3, 7, 10, 14 and healing rates were calculated. After 14-day treatment, the paw withdrawal mechanical threshold (PWMT) as well as paw withdrawal thermal latency were measured. In addition, CD31 expression in burn wound was detected by immunohistochemistry. The contents of TNF-α and IL-1ß in wound tissues were detected by ELISA. Moreover, the mRNA and protein expression levels of VEGF, MMP-9, and TGF-ß1 in wound tissues were detected by RT-qPCR together with Western blot. Burn wound of rats in the PRP group gradually got better with a decreased wound area. Compared with the NS group, the wound area of the PRP group was significantly reduced and the healing rate was significantly increased. Meanwhile, PWMT of the rats in the PRP group was obviously increased compared with the NS group. Compared with the NS group, the rate of CD31-positive cells in the wound tissue of burned rats was increased; while the contents of TNF-α and IL-1ß were significantly decreased after a subcutaneous injection of PRP. In addition, the mRNA and protein expression levels of VEGF, MMP-9, and TGF-ß1 in the wound tissue of rats from PRP group were evidently increased. Autologous platelet-rich plasma not only shortened the healing time, but also relieved the burn pain.


Assuntos
Queimaduras/terapia , Manejo da Dor/métodos , Plasma Rico em Plaquetas , Cicatrização , Animais , Biomarcadores/metabolismo , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-Dawley , Transplante Autólogo
8.
Microorganisms ; 9(10)2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-34683411

RESUMO

BACKGROUND: Staphylococcus aureus is a leading cause of contagious mastitis in dairy cattle. Internalization of S. aureus by bovine mammary gland epithelial cells is thought to be responsible for persistent and chronic intramammary infection, but the underlying mechanisms are not fully understood. METHODS: In the present study, we evaluated the role of Annexin A2 (AnxA2), a membrane-binding protein, in S. aureus invasion into bovine mammary epithelial cell line (MAC-T). In vitro binding assays were performed to co-immunoprecipitate the binding proteins of AnxA2 in the lysates of S. aureus. RESULTS: AnxA2 mediated the internalization but not adherence of S. aureus. Engagement of AnxA2 stimulated an integrin-linked protein kinase (ILK)/p38 MAPK cascade to induce S. aureus invasion. One of the AnxA2-precipitated proteins was identified as S. aureus clumping factor B (ClfB) through use of mass spectrometry. Direct binding of ClfB to AnxA2 was further confirmed by using a pull-down assay. Pre-incubation with recombinant ClfB protein enhanced S. aureus internalization, an effect that was specially blocked by anti-AnxA2 antibody. CONCLUSION: Our results demonstrate that binding of ClfB to AnxA2 has a function in promoting S. aureus internalization. Targeting the interaction of ClfB and AnxA2 may confer protection against S. aureus mastitis.

9.
Chem Commun (Camb) ; 57(77): 9894-9897, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34494043

RESUMO

Herein, we report the first example of controllable magnetoresistance in a semiconducting carbonized phthalonitrile resin. This special phenomenon is explained using the different ratios of graphite-like (sp2) and diamond-like (sp3) bonds and localization length (a0) as well as the density of states at the Fermi-level (N(EF)).

10.
Langmuir ; 37(6): 2129-2139, 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33502207

RESUMO

Direct ink writing (DIW) of aerogels has great potential in designing novel three-dimensional (3D) multifunctional materials with hierarchical structures ranging from the nanoscale to the macroscopic scale. In this paper, pure aerogels composed of inorganics, strongly cross-linking organics, and weakly cross-linking organics were directly written via the precise control of the gelation degree without using any additives. The rheological properties of a resorcinol-formaldehyde aerogel-based sol-gel ink (marked as RA ink) were measured at different reaction times to determine the suitable printable range (G'LVR: several 103 Pa) that ensures its good print fidelity. In addition, the rheological evolution of the RA ink during the sol-gel process and under different shear stresses was studied. The correlation of relevant parameters was established according to the Hagen-Poiseuille model. Other typical aerogel-based sol-gel inks including a silica aerogel-based sol-gel ink (SA ink) and a polyimide aerogel-based sol-gel ink (PA ink) for DIW were also demonstrated. Finally, water evaporation experiments were carried out using a 3D-printed carbonized resorcinol-formaldehyde aerogel (CA) to further exhibit the potential applications of this novel technology in solar steam generation. The evaporation rate (1.57 kg m-2 h-1) and efficiency (88.38%) of 3D-printed CA were higher than those of bulk CA (1.21 kg m-2 h-1 and 69.82%). This paper systematically studies the control of DIW parameters for aerogel-based sol-gel inks and shows a potential application in high-efficiency 3D-printed evaporators.

11.
Nanomaterials (Basel) ; 10(12)2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33339289

RESUMO

Resorcinol-formaldehyde/titanium dioxide composite (RF/TiO2) gel was prepared simultaneously by acid catalysis and then dried to aerogel with supercritical fluid CO2. The carbon/titanium dioxide aerogel was obtained by carbonization and then converted to nanoporous titanium carbide/carbon composite aerogel via 800 °C magnesiothermic catalysis. Meanwhile, the evolution of the samples in different stages was characterized by X-ray diffraction (XRD), an energy-dispersive X-ray (EDX) spectrometer, a scanning electron microscope (SEM), a transmission electron microscope (TEM) and specific surface area analysis (BET). The results showed that the final product was nanoporous TiC/C composite aerogel with a low apparent density of 339.5 mg/cm3 and a high specific surface area of 459.5 m2/g. Comparing to C aerogel, it could also be considered as one type of highly potential material with efficient photothermal conversion. The idea of converting oxide-carbon composite into titanium carbide via the confining template and low-temperature magnesiothermic catalysis may provide new sight to the synthesis of novel nanoscale carbide materials.

12.
Molecules ; 25(22)2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33202918

RESUMO

Resveratrol (RSV) is a natural flavonoid polyphenol compound extracted from the plants which shows various biological activities. However, the clinical application of RSV is limited by its poor aqueous solubility, rapid metabolism and poor bioavailability. In this study, resveratrol-loaded solid lipid nanoparticles (RSV- SLNs) was design as a nano-antioxidant against the physical fatigue. The resultant RSV-SLNs were characterized by photon correlation spectroscopy (PCS), transmission electron micrographs (TEM), zeta potential, differential scanning calorimetry (DSC) and Raman spectroscopy pattern. Furthermore, the in vivo anti-fatigue effect assays showed that RSV-SLNs prolonged the mice exhausted time and running distance. The biochemical parameters of blood related to fatigue suggested that RSV-SLNs have potential applications to improve the antioxidant defense of the mice after extensive exercise and confer anti-fatigue capability. Furthermore, the molecular mechanisms of antioxidant by RSV-SLNs supplementation was investigated through the analysis of silent information regulator 2 homolog 1 (SIRT1) protein expression, which demonstrated that it could downregulate the expression of SIRT1 and increase autophagy markers, microtubule-associated protein 1 light chain 3-II (LC3-II) and sequestosome-1 (SQSTM1/p62). These results reveal that the RSV-SLNs may have great potential used as a novel anti-fatigue sports nutritional supplement.


Assuntos
Suplementos Nutricionais , Fadiga/prevenção & controle , Lipídeos/química , Nanopartículas/química , Condicionamento Físico Animal , Resveratrol/química , Animais , Antioxidantes/química , Disponibilidade Biológica , Varredura Diferencial de Calorimetria , Portadores de Fármacos/química , Peroxidação de Lipídeos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Proteínas Associadas aos Microtúbulos/metabolismo , Tamanho da Partícula , Proteína Sequestossoma-1/metabolismo , Sirtuína 1/metabolismo , Solubilidade , Análise Espectral Raman , Fenômenos Fisiológicos da Nutrição Esportiva
13.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 36(3): 235-239, 2020 May.
Artigo em Chinês | MEDLINE | ID: mdl-32981278

RESUMO

Objective: To investigate the effects of exogenous NaHS on myelin basic protein (MBP) and learning and memory of hippocampal neurons in mice with spinocerebellar ataxia type 3 (SCA3) and its therapeutic significance.Methods: Twelve male normal mice were randomly selected as normal control group (NC Group), and 48 SCA3 mice were randomly selected as SCA3 model group (M Group), low dose group (NL Group, 10 µmol/kg), medium dose group (NM Group, 50µmol/kg) and high dose group (NH Group, 100 µmol/kg), 12 rats in each group. The drug treated groups were injected with NaHS intraperitoneally once a day for 4 weeks. The changes of learning and memory ability of SCA3 mice before and after the intervention of different doses of NaHS were determined by Morris water maze, the content of hydrogen sulfide (H2S) in hippocampus was measured by spectrophotometry, the expression of MBP was detected by immunohistochemistry, and the morphological changes of neuron myelin sheath were observed by electron microscope. Results: Compared with the control group, the learning and memory ability of SCA3 mice was decreased significantly (P<0.05), and the content of H2S in hippocampus was decreased (P<0.05). After different doses of exogenous NaHS treatment, the learning and memory ability was improved in different degrees (P<0.05), and the contents of H2S and MBP in hippocampus of SCA3 mice were also improved in different degrees (P<0.05). Conclusion: Exogenous NaHS may increase the contents of H2S and MBP in the hippocampus of SCA3 mice, which may have a protective effect on the neurons, and then improve the learning and memory ability of SCA3 mice, and provide a new idea for the treatment of SCA3.


Assuntos
Sulfeto de Hidrogênio , Aprendizagem , Memória , Ataxias Espinocerebelares , Sulfetos , Animais , Hipocampo/efeitos dos fármacos , Aprendizagem/efeitos dos fármacos , Masculino , Memória/efeitos dos fármacos , Camundongos , Proteína Básica da Mielina , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Ratos , Ataxias Espinocerebelares/tratamento farmacológico , Sulfetos/farmacologia , Sulfetos/uso terapêutico
14.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 36(2): 138-142, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32744007

RESUMO

Objective: To investigate the effects of butylphthalide (NBP) on learning and memory related ability, hydrogen sulfide (H2S) content in hippocampus and amygdala, cystathionine-ß-synthase (CBS) expression and mitochondrial ATPase activity in rats with chronic alcoholism. Methods: Ninety SD male rats were randomly divided into three groups: normal control group (NC), model group (M) and butylphthalide remedy group (BR). Except for the control group, the water solution containing 6% (v/v) alcohol was used as the sole source of drinking water in the other two groups. After 14 days of feeding, the butylphthalide remedy group was injected with NBP intraperitoneally at the dose of 5 mg/kg once a day for 14 consecutive days, and the remaining two groups were injected with the same dose of normal saline. The control group subsequently used the Morris water maze method to observe and record the animals after entering the water. The time required for the underwater platform, their strategies and their swimming trajectories could analyze and infer the animal's ability to learn and remember. H2S concentration, CBS expression and mitochondrial ATPase activity in hippocampus and amygdale were dectected. Results: Compared with NC group, the latency period and swimming distance of M group were increased, the content of H2S and the mean optical density of CBS in hippocampus and amygdala were increased, and the activity of mitochondrial ATPase in hippocampus and amygdala was decreased significantly (P<0. 01) . Compared with the M group, the latency period and swimming distance of learning and memory performance of BR group were decreased, the content of H2S and the mean optical density of CBS in hippocampus and amygdala were decreased, and the activity of mitochondrial ATPase in hippocampus and amygdala was increased significantly (P<0. 01) . Conclusion: NBP can alleviate the effect of ethanol on learning and memory in rats, which may be related to the effect of NBP on the concentration of H2S and the expression of CBS in the amygdala of hippocampus and the increase of ATPase activity.


Assuntos
Alcoolismo , Tonsila do Cerebelo/efeitos dos fármacos , Benzofuranos/farmacologia , Cistationina beta-Sintase/metabolismo , Hipocampo/efeitos dos fármacos , Sulfeto de Hidrogênio/metabolismo , Animais , Aprendizagem , Masculino , Memória , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
15.
Molecules ; 25(12)2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32549204

RESUMO

Silica aerogel, a kind of nanoporous material, is regarded as a desired drug carrier for its low toxicity, high specific surface area, and excellent biocompatibility. Using silica aerogel in a drug carrier may be an appropriate method to improve the performance of pure resveratrol. In this study, resveratrol-loaded silica aerogel (RSA) as a drug delivery system was prepared by the sol-gel method. Before gelling, resveratrol was added into the hydrolyzed tetraethyl orthosilicate (TEOS) ethanol solution then dispersed by stir and ultrasound. The results showed that RSA has a high loading rate of 19% with low cost and excellent biocompatibility. The SEM images showed that silica aerogel wraps up outside the resveratrol. Sustained releasing effect could be observed in RSA after 1 h, while pure resveratrol did not display this. The release of RSA lasted for over 6 h, and the release amount reached over 90% and 80% in either simulated gastric fluid (pH = 2.0) or phosphate-buffered saline (pH = 7.4) at 37 °C. Preliminary in vitro toxicity test revealed RSA to be biocompatible and stable; and when coupled with the anti-inflammatory effects of resveratrol, showed good potential for osteoarthritis treatment.


Assuntos
Resveratrol/administração & dosagem , Sílica Gel/química , Preparações de Ação Retardada , Portadores de Fármacos/química , Géis/química , Cinética , Porosidade , Resveratrol/farmacologia , Sílica Gel/metabolismo , Sílica Gel/farmacologia , Dióxido de Silício/química
16.
Materials (Basel) ; 13(7)2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32244773

RESUMO

Resveratrol is a natural active ingredient found in plants, which is a polyphenolic compound and has a variety of pharmaceutical uses. Resveratrol-loaded TEMPO-oxidized cellulose aerogel (RLTA) was prepared using a freeze-drying method, employing high speed homogenization followed by rapid freezing with liquid nitrogen. RLTAs were designed at varying drug-cellulose aerogel ratios (1:2, 2:3, 3:2, and 2:1). It could be seen via scanning electron microscopy (SEM) that Res integrated into TEMPO-oxidized cellulose (TC) at different ratios, which changed its aggregation state and turned it into a short rod-like structure. Fourier transform infrared (FTIR) spectra confirmed that the RLTAs had the characteristic peaks of TC and Res. In addition, X-ray diffraction (XRD) demonstrated that the grain size of RLTA was obviously smaller than that of pure Res. RLTAs also had excellent stability in both simulated gastric fluid and phosphate buffer solution. The drug release rate was initially completed within 5 h under a loading rate of 30.7 wt%. The results of an MTT assay showed the low toxicity and good biocompatibility of the RLTAs. TC aerogel could be a promising drug carrier that may be widely used in designing and preparing novel biomedicine.

17.
Parasit Vectors ; 13(1): 40, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31996262

RESUMO

BACKGROUND: Haemonchus contortus, a blood-feeding parasite, is constantly surrounded by large quantities of heme released from the catabolism of host red blood cells. To cope with the toxicity of free heme, H. contortus needs to uptake and detoxify the heme, a process believed to be paramount for parasite survival. METHODS: A heme-responsive gene Hc-hrg-2 was identified which is the homologue of Ce-hrg-2. The transcriptional levels in all developmental stages and heme-responsive ability of Hc-hrg-2 were analyzed by qRT-PCR. Immunofluorescence analysis and cell transfections were performed to analyze the expression pattern of Hc-HGR-2. Statistical analyses were performed with GraghPad Prism 6.0 using Student's t-test. RESULTS: To investigate the heme homeostasis of H. contortus, we first identified a heme-responsive gene Hc-hrg-2, a homolog of Ce-hrg-2 that is involved in heme transport in the hypodermis of Caenorhabditis elegans. Using qRT-PCR, we showed that Hc-hrg-2 mRNA was expressed throughout all life-cycle stages of H. contortus with the highest level in the third-stage larvae (L3s). Notably, transcription of Hc-hrg-2 in the exsheathed L3s was significantly upregulated in the presence of high concentration of heme. We found that Hc-HRG-2 protein was mainly located in the hypodermal tissues of adult H. contortus in vivo and the endoplasmic reticulum in the transfected mammalian cells. Our in vitro assay demonstrated that Hc-HRG-2 is a heme-binding protein with glutathione S-transferase activity and heme had a significant effect on its enzymatic activity when a model substrate 1-chloro-2, 4-dinitrobenzene (CDNB) was used. CONCLUSIONS: Hc-hrg-2 is a heme-responsive gene and engaged in heme homeostasis regulation in hypodermal tissues during the free-living stages of H. contortus.


Assuntos
Glutationa Transferase/genética , Haemonchus/genética , Heme/metabolismo , Hemeproteínas/genética , Sequência de Aminoácidos , Animais , Caenorhabditis elegans/enzimologia , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/química , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Retículo Endoplasmático/metabolismo , Feminino , Imunofluorescência , Glutationa Transferase/química , Glutationa Transferase/metabolismo , Haemonchus/enzimologia , Haemonchus/metabolismo , Hemeproteínas/química , Hemeproteínas/metabolismo , Homeostase/genética , Masculino , Camundongos , Camundongos Endogâmicos ICR , Reação em Cadeia da Polimerase em Tempo Real , Alinhamento de Sequência , Ativação Transcricional , Regulação para Cima
18.
Molecules ; 24(21)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683567

RESUMO

The trans-resveratrol (RSV)-loaded silica aerogel (RLSA) was prepared by the sol-gel method, adding the drug during the aging process, solvent replacement and freeze drying. A series of characterizations showed that RSV stays in the silica aerogel in two ways. First, RSV precipitates due to minimal solubility in water during the solvent replacement process. After freeze drying, the solvent evaporates and the RSV recrystallizes. It can be seen from scanning electron microscope (SEM) and transmission electron microscope (TEM) images that the recrystallized RSV with micron-sized long rod-shaped is integrated with the dense silica network skeleton. Second, from small-angle X-ray scattering (SAXS) results, a portion of the RSV molecules is not crystallized and the size is extremely small. This can be attached to the primary and secondary particles of silica to enhance its network structure and inhibit shrinkage, which is why the volume and pore size of RLSA is larger. In addition, the diffusion of RSV in silica alcogel was studied by a one-dimensional model. The apparent diffusion coefficients of inward diffusion, outward diffusion and internal diffusion were calculated by fitting the time- and position-dependent concentration data. It was found that the outward diffusion coefficient (5.25 × 10-10 m2/s) is larger than the inward (2.93 × 10-10 m2/s), which is probably due to the interface effect. The diffusion coefficients obtained for different concentrations in the same process (inward diffusion) are found to be different. This suggests that the apparent diffusion coefficient obtained is affected by molecular adsorption.


Assuntos
Géis/química , Resveratrol/química , Dióxido de Silício/química , Adsorção , Difusão , Liofilização , Nitrogênio/química , Porosidade , Espalhamento a Baixo Ângulo , Temperatura , Termogravimetria , Difração de Raios X
19.
ACS Appl Mater Interfaces ; 11(45): 42057-42065, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31631656

RESUMO

Ecofriendly, highly effective, and low-cost solar steam generation has great potential in the applications of power generation, seawater desalination, and industry wastewater treatment. Solar steam generation requires an evaporator that has strong light absorption over a wide-frequency band (200-3000 nm), high photothermal conversion efficiency, and good thermal insulation to avoid excessive heat loss. Herein, foam-strengthened ultrablack carbon aerogels (CAs) with micropores, mesopores, and macropores were prepared using freeze drying. The small-size conductor effect in ultrablack CAs could increase the surface electron concentration, leading to the increase of light absorption and ultimately enhancing photothermal conversion efficiency. Consequently, under 1 sun illumination, dried CA-5 exhibited a fast temperature rise rate and the highest thermal equilibrium temperature of 87.6 °C among CAs, the equilibrium temperature is 20.8 °C higher than that of the foam. Besides, CA-5 exhibited a high water evaporation rate of 1.29 kg m-2 h-1 under only 1 sun illumination. To further increase the hot-electron effect, CO2 activation was implemented. The highest water evaporation rate among activated CAs (ACAs) was 1.37 kg m-2 h-1, which is about 2.85 times higher than that of pure water. The highest water evaporation efficiency was 87.51%, which is better than most of the previously reported evaporation efficiencies. Besides the hot-electron enhancement effect, ACAs with thermal insulation, mechanical strength, and thermal stability show great potential for producing fresh water from seawater, industrial wastewater, and even concentrated acidic or alkaline solutions.

20.
Nanotechnology ; 30(35): 354001, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31035266

RESUMO

Pyrolysis, which involves thermal decomposition of materials at elevated temperatures, has been commonly applied in the chemical industry. Here we explored the pyrolysis process for 3D nanofabrication. By strain engineering of nanomembranes on a thermal responsive polymer as the sacrificial layer, we demonstrated that diverse 3D rolled-up microstructures with different functions could be achieved without any additional solution and drying process. We carefully studied the effect of molecular weight of the polymer in the pyrolysis process and identified that the rapid breakdown of molecular backbone to a monomer is the key for nanomembrane releasing and rolling. Preferential rolling direction and corresponding dynamics were studied by analyzing the real-time video of the rolling process. We further demonstrated the versatile functions of the fabricated 3D structures as catalytic microengines and optical resonators. The simple fabrication methodology developed here may have great potential in producing functional 3D tubular micro-/nanostructures.

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