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1.
Appl Opt ; 60(23): 7007-7016, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34613184

RESUMO

A three-dimensional (3D) measurement method of color fringe projection based on an improved three-step phase-shifting method is proposed. The color fringe pattern is encoded by two cosine fringe patterns with the same frequency but different shifting phase and a uniform gray flat image into three color channels R, G, and B. Although the measurement speed of the traditional three-step phase-shifting method can meet the requirements of measuring 3D objects, it makes the noise and inaccuracy of the captured images increase, and each image will cause measurement error. Therefore, we improve the three-step phase-shifting method and introduce the Hilbert transform into the three-step phase-shift method. The DC component of the fringe pattern is obtained by using the Hilbert transform principle, and the third fringe pattern in the three-step phase-shift method is replaced by the captured light intensity distribution of the DC component. The phase difference of the other two fringe patterns is fixed as π/2 by the Hilbert transform. The improved three-step phase-shifting method is used to obtain the phase information of the deformed color fringe image, and then the phase-unwrapping algorithm is used to obtain the phase distribution information of the whole field. The results show that the improved method can not only accurately calculate the phase information but also greatly improve the measurement speed and quality.

2.
Sci Rep ; 11(1): 18451, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34531475

RESUMO

This study investigates the protective effect of Erigeron breviscapus injection, a classic traditional Chinese medicine most typically used by Chinese minority to treat stroke, on cerebral ischemia-reperfusion injury and the related signaling pathways. Use network pharmacology methods to study the relationship between E. breviscapus (Vant.) Hand-Mazz. and ischemic stroke, predict the mechanism and active ingredients of E. breviscapus (Vant.) Hand-Mazz. in improving ischemic stroke disease. We study the protective effect of E. breviscapus injection on blood-brain barrier (BBB) injuries induced by cerebral ischemia in rats by regulating the ROS/RNS-MMPs-TJs signaling pathway. The rat model of focal cerebral ischemia-reperfusion injury has been prepared using the wire-suppository method. Firstly, the efficacy of E. breviscapus injection, Scutellarin and 3,5-dicaffeoylquinic acid in protecting BBB injury caused by cerebral ischemia has been evaluated. Secondly, the following two methods have been used to study the mechanism of E. breviscapus injection in regulating the ROS/RNS-MMPS-TJS signaling pathway: real-time PCR and western blot for the determination of iNOS, MMP-9, claudin-5, occludin, ZO-1 mRNA and protein expression in brain tissue. We find that PI3K-Akt signaling pathway predicted by network pharmaology affects the blood-brain barrier function, so we chose the blood-brain barrier-related MMP-9, claudin-5, iNOS, occludin and ZO-1 proteins are used for research. The results of our research show that 3 drugs can reduce the rate of cerebral infarction in rats, relieve the abnormal neuroethology of rats, reduce the degree of brain tissue lesion, increase the number of the Nissl corpuscle cells and repair the neuron ultrastructure in injured rats. At the same time, it can obviously reduce the ultrastructure damage of the BBB in rats. All three drugs significantly reduced the content of Evans blue in the ischemic brain tissue caused by cerebral ischemia in rats with BBB injury. In addition, E. breviscapus injection, Scutellarin and 3,5-dicaffeoylquinic acid can decrease the protein expression of iNOS and MMP-9 in rat ischemic brain tissue. In addition, 3,5-dicaffeoylquinic acid can increase the protein expression of claudin-5. We conclude that E. breviscapus injection, Scutellarin and 3,5-dicaffeoylquinic acid have obvious therapeutic effects on BBB and neuron injury induced by cerebral ischemia in rats. Our results from studying the mechanism of action show that E. breviscapus injection and Scutellarin inhibited the activation of MMP-9 by inhibiting the synthesis of iNOS, 3,5-dicaffeoylquinic acid inhibits the expression and activation of MMP-9 by inhibiting the activation of iNOS and reducing the generation of free radicals, thus reducing the degradation of important cytoskeleton connexin claudin-5 in the tight junction (TJ) structure by inhibiting the expression and activation of MMP-9. Finally BBB structure integrity was protected.

3.
Water Res ; 204: 117628, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34507021

RESUMO

Both biological sulfate reduction process and sulfur reduction process are attractive technologies for metal-laden wastewater treatment. However, the acidity stress of metal-laden wastewater could affect the sulfidogenic performance and the microbial community, weaken the stability, efficiency and cost-effectiveness of the biological sulfidogenic processes (BSP). In this study, long-term lab-scale trials were conducted with a sulfate-reducing bioreactor and a sulfur-reducing bioreactor to evaluate the effects of acidity on sulfidogenic activities and the microbial community of the BSP. In the 300-day trial, the sulfate-reducing bacteria (SRB)-driven BSP was stable in terms of sulfidogenic performance and microbial community with the decline of pH, while the sulfur-reducing bacteria (S0RB)-driven BSP achieved high-rate and low-cost sulfide production under neutral conditions but unstable under acidic conditions. With the decline of pH, the sulfide production rate (SPR) of the SRB-driven BSP stably increased from 30 to 83 mg S/L-h; while it decreased from 56 to 37 mg S/L-h in the S0RB-driven BSP with high fluctuation. The results of estimation were consistent with the thermodynamical calculations, in which the sulfur reduction process showed a better performance at pH 5-7, while the sulfate reduction process might gain more energy when pH<5. The stable sulfidogenic performance and microbial community diversity of the SRB-driven BSP could be attributed to the alkalinity produced in sulfate reduction to buffer the acidic stress. In comparison, the microbial community in the S0RB-driven BSP was significantly re-shaped by acidity stress, and the predominant sulfidogenic bacterium changed from Desulfovibrio at neutral condition, to Desulfurella at pH≤5.4. The stability of the microbial community significantly affected the SPR and the operational cost. Nevertheless, the organic consumption for sulfide production of the S0RB-driven BSP was still less than the SRB-driven BSP even in acidic conditions. Collectively, the S0RB-driven BSP was recommended under neutral or mild acid conditions, while the SRB-driven BSP was more suitable under fluctuating pH conditions, especially at low pH. Overall, this study presented the long-term performance of SRB- and S0RB-driven BSP under varying pH conditions, and provided guidance to determine the suitable BSP and operational cost for different metal-laden wastewater.


Assuntos
Enxofre , Águas Residuárias , Concentração de Íons de Hidrogênio , Metais , Sulfatos
4.
Mol Med Rep ; 24(4)2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34396425

RESUMO

Gastric cancer (GC) is one of the most common types of malignancy worldwide and is accompanied by both high mortality and morbidity rates. Homeobox B13 (HOXB13) has been reported to act as a tumor suppressor gene in multiple types of human cancer. The present study aimed to investigate the effects and potential underlying molecular mechanisms of HOXB13 in the progression of GC. The expression of HOXB13 in GC cells was first examined using the Cancer Cell Line Encyclopedia database and subsequently validated in a number of GC cell lines. Following HOXB13 overexpression (Ov­HOXB13), HGC­27 cell proliferation was evaluated by colony formation and Cell Counting Kit­8 assays. Wound healing and Matrigel assays were used to determine the migratory and invasive abilities, respectively. Additionally, cell apoptosis was assessed using TUNEL staining, and the expression of apoptosis­related proteins was detected by western blot analysis. Subsequently, TEA domain transcription factor 4 (TEAD4) was overexpressed to evaluate the effects on HGC­27 cell proliferation, migration, invasion and apoptosis following co­transfection with Ov­HOXB13. The potential binding sites of HOXB13 on the vestigial­like family member 4 (VGLL4) promoter were verified using chromatin immunoprecipitation and dual luciferase reporter assays. Moreover, the expression levels of proteins involved in the Hippo signaling pathway were analyzed using western blotting. The results revealed that the expression of HOXB13 was notably lower in GC cells compared with normal gastric cells. The overexpression of HOXB13 significantly inhibited the proliferation, migration and invasion, but promoted the apoptosis of HGC­27 cells. Moreover, Ov­HOXB13 downregulated TEAD4 expression. Notably, Ov­TEAD4 transfection partially reversed the effects of Ov­HOXB13 on the cellular behaviors of HGC­27 cells. HOXB13 was also confirmed to bind with the VGLL4 promoter. The knockdown of VGLL4 restored the inhibitory effects of Ov­HOXB13 on the expression levels of VGLL4 and Hippo pathway signaling proteins. In conclusion, the findings of the present study suggested that Ov­HOXB13 may suppress the proliferation, migration and invasion, and promote the apoptosis of GC cells through the transcriptional activation of VGLL4 to inhibit the involvement of TEAD4 in the Hippo signaling pathway. These results may provide novel and potent targets for the treatment of GC.

5.
Chemosphere ; 282: 131089, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34119730

RESUMO

Dwarf bamboo is a woody plant with potential for use in the remediation of Pb-contaminated soil. Due to its clonal growth habit, there are two keys to its application for continuous soil Pb remediation: 1) its ability to form shoots and grow into new bamboo normally under Pb stress and 2) the Pb tolerance and accumulation characteristics of this new bamboo. Here, 5 species of dwarf bamboo were treated with 2 levels of soil Pb stress (0 and 1500 mg kg-1). In the roots of 3 of the species (Sasa argenteostriata, Sasaella glabra, and Indocalamus decorus), Pb tended to be distributed along the cell wall and transported to vacuoles. In the other 2 species (Sasa auricoma and Sasa fortunei), Pb was arranged linearly along the cell wall. Under Pb treatment, the new bamboo of all species showed gradual physiological adaptation to Pb stress. Correlations of the net photosynthetic rate, superoxide dismutase activity, and free proline levels with Pb content in new leaves in November were all higher than those in July, though that of malondialdehyde content decreased, suggesting that new dwarf bamboo exhibits good soil Pb stress tolerance. Sasa argenteostriata and Indocalamus decorus consistently maintained higher antioxidant enzyme activities and free proline levels than the other species under Pb treatment, and the total biomass per pot of the new bamboo decreased the least compared to that in the Pb-free treatment for these two species. Therefore, these bamboo species may be used in the long-term continuous remediation of Pb-contaminated soil.


Assuntos
Sasa , Poluentes do Solo , Biodegradação Ambiental , Chumbo/toxicidade , Raízes de Plantas/química , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
6.
Sci Total Environ ; 780: 146597, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34030325

RESUMO

The aim of this study was to investigate the performance of single-chamber MEC under applied voltages higher than that for water electrolysis. With different acetate concentrations (1.0-2.0 g/L), the MEC was tested under applied voltages from 0.8 to 2.2 V within 2600 h (54 cycles). Results showed that the MEC was stably operated for the first time within 20 cycles under 2.0 and 2.2 V, compared with the control MEC with significant water electrolysis. The maximum current density reached 27.8 ± 1.4 A/m2 under 2.0 V, which was about three times as that under 0.8 V. The anode potential in the MEC could be kept at 0.832 ± 0.110 V (vs. Ag/AgCl) under 2.2 V, thus without water electrolysis in the MEC. High applied voltage of 1.6 V combined with alkaline solution (pH = 11.2) could result in high hydrogen production and high current density. The maximum current density of MEC at 1.6 V and pH = 11.2 reached 42.0 ± 10.0 A/m2, which was 1.85 times as that at 1.6 V and pH = 7.0. The average hydrogen content reached 97.2% of the total biogas throughout all the cycles, indicating that the methanogenesis was successfully inhibited in the MEC at 1.6 V and pH = 11.2. With high hydrogen production rate and current density, the size and investment of MEC could be significantly reduced under high applied voltages. Our results should be useful for extending the range of applied voltages in the MEC.


Assuntos
Fontes de Energia Bioelétrica , Eletrólise , Acetatos , Biocombustíveis , Eletrodos , Hidrogênio
7.
J Mol Neurosci ; 71(2): 302-324, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32757108

RESUMO

By measuring the cerebral infarction rate and neurological behavioral score of rats in a sham operation group, an MCAO model control group and an Erigeron breviscapus injection treatment group, we explored the therapeutic effects of Erigeron breviscapus injection on brain tissue and neuroethological injury in rats. Plasma samples were collected at 18 time points after intravenous injection of Erigeron breviscapus. The levels of scutellarin, 4-caffeoylquinic acid, 5-caffeoylquinic acid, 3,5-dicaffeoylquinic acid, 4,5-dicaffeoylquinic acid, chlorogenic acid and isochlorogenic acid B in rat plasma at the various time points were determined by an HPLC method, and drug concentration versus time plots were constructed to estimate the pharmacokinetic parameters. Finally, a PK-PD combined model was used to analyze the relationship between the blood concentration, time and therapeutic effects of the seven active components. The results of the pharmacodynamics studies showed that the cerebral infarction rate of rats in the Erigeron breviscapus injection group decreased significantly at 5 min, 10 min, 20 min, 6 h, 8 h, 18 h, 24 h, 32 h, 40 h and 48 h after cerebral ischemia. Abnormal neurological behavior scores were significantly reduced after 4 h of cerebral ischemia. The pharmacokinetics results showed that the seven chemical constituents in Erigeron breviscapus injection reached their highest detection value after 5 min of cerebral ischemia. The lowest detection values of scutellarin and isochlorogenic acid B appeared after 6 h of cerebral ischemia but could not be detected after 8 h. The lowest detection values of 5-caffeoylquinic acid and 4,5-dicaffeoylquinic acid were found in the third hour of cerebral ischemia but not after 4 h. The lowest detection values of 4-caffeoylquinic acid, 3,5-dicaffeoylquinic acid and chlorogenic acid were found during the second hour of cerebral ischemia but not at the third hour. However, at 18 h, 24 h, 32 h and 40 h of cerebral ischemia, the cerebral infarction rates of rats in the Erigeron breviscapus injection group were significantly reduced, with decreased values of 6.22%, 11.71%, 6.92% and 4.96%, respectively, and the effects were stronger than those after 5-20 min of cerebral ischemia. The decreased values reached their highest value after 24 h of cerebral ischemia. Our results show that the effects of Erigeron breviscapus injection on reducing the cerebral infarct rate in MCAO model rats are characterized by a fast onset and long maintenance time. The 5-min blood concentration in cerebral ischemia was the highest test value, and after this time, the cerebral infarction rate of MCAO rats began to decrease. However, the peak value of the effects lagged behind that of the plasma concentration. The maximum effective time for Erigeron breviscapus injection appeared 24 h after cerebral ischemia, which provides a reference for the screening of specific drugs for ischemic stroke, optimal dosing regimens and rational clinical drug use. Graphical Abstract.

8.
Chemosphere ; 268: 128800, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33143885

RESUMO

Modifying the electrodes of microbial fuel cells (MFCs) with iron oxides can improve the bacterial attachment performances and electrocatalytic activities for energy conversion, which is of significance in the fabrication of MFCs. However, the conventional modification methods usually result in the aggregation of iron sites, producing the electrodes of poor qualities. Herein, we report a novel method for the modification of electrochemical electrodes to boost the anode performance of MFC. The Shewanella precursor adhered on carbon felt electrode was directly carbonized to form a bacteria-derived biological iron oxide/carbon (Bio-FeOx/C) nanocomposite catalyst. The large spatial separation between the bacteria, as well as those between the iron containing proteins in the bacteria, deliver a highly dispersed Bio-FeOx/C nanocomposite with good electrocatalytic activities. The excellent microbial attachment performance and electron transfer rate of the Bio-FeOx/C modified electrode significantly promote the transfer of produced electrons between bacteria and electrode. Accordingly, the MFC with the Bio-FeOx/C electrode exhibits the maximum power density of 797.0 mW m-2, much higher than that obtained with the conventional carbon felt anode (226.1 mW m-2). Our works have paved a new avenue to the conversion of the natural bacterial precursors into active iron oxide nanoparticles as the anode catalyst of MFCs. The high catalytic activity of the prepared Bio-FeOx endows it great application potentials in the construction of high-performance electrodes.


Assuntos
Fontes de Energia Bioelétrica , Nanocompostos , Carbono , Eletrodos , Compostos Férricos
9.
Chemosphere ; 265: 129088, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33280848

RESUMO

The aim of this study was to investigate pH effect on stratification of bacterial community in cathodic biofilm of the microbial fuel cell (MFC) under alkaline conditions. A single-chamber MFC with air-cathode was operated with 0.8 g/L maltodextrin and bicarbonate buffer solutions under pH values of 8.5, 9.5, and 10.5, respectively. The cathodic biofilms were characterized by linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS), confocal laser scanning microscopy (CLSM), freezing microtome and high-throughput sequencing analysis on bacterial communities, respectively. Results showed that the maximum power densities in the MFC increased with the pH values and reached 1221 ± 96 mW/m2 at pH = 10.5 during ∼30 d of operation. With different pH values, the composition and relative abundance of bacterial community significantly changed in the bottom (0-50 µm), middle (50-100 µm), and top (100-150 µm) layers of the cathodic biofilm. With pH = 10.5, aerobic bacteria accounted for 12%, 13%, and 34% of the bacterial community in the top, middle, and bottom layers, respectively. The amount of anaerobic bacteria in the top and middle layers (i.e., 52%, and 50% of the bacterial community, respectively) was higher than that in the bottom layer (22%). The distribution of aerobic and anaerobic bacteria showed a "valley-peak" structure within the layers. The high CO32- concentration facilitates the hydroxyl transfer and the neutralization in the anode of the MFC under high alkali conditions. The results from this study should be useful to develop new catalyst and cathode in the MFC.


Assuntos
Fontes de Energia Bioelétrica , Biofilmes , Eletrodos , Concentração de Íons de Hidrogênio , Polissacarídeos
10.
Mol Plant Pathol ; 21(7): 936-950, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32512647

RESUMO

The ascomycete fungus Colletotrichum fructicola causes diseases on a broad range of plant species. On susceptible cultivars of apple, it induces severe early defoliation and fruit spots, named glomerella leaf spot (GLS), but the mechanisms of pathogenicity have remained elusive. Phytopathogens exhibit small secreted effectors to advance host infection by manipulating host immune reactions. We report the identification and characterization of CfEC92, an effector required for C. fructicola virulence. CfEC92 is a Colletotrichum-specific small secreted protein that suppresses BAX-triggered cell death in Nicotiana benthamiana. Accumulation of the gene transcript was barely detectable in conidia or vegetative hyphae, but was highly up-regulated in appressoria formed during early apple leaf infection. Gene deletion mutants were not affected in vegetative growth, appressorium formation, or appressorium-mediated cellophane penetration. However, the mutants were significantly reduced in virulence toward apple leaves and fruits. Microscopic examination indicated that infection by the deletion mutants elicited elevated deposition of papillae at the penetration sites, and formation of infection vesicles and primary hyphae was retarded. Signal peptide activity, subcellular localization, and cell death-suppressive activity (without signal peptide) assays suggest that CfEC92 could be secreted and perform virulence functions inside plant cells. RNA sequencing and quantitative reverse transcription PCR results confirmed that the deletion mutants triggered elevated host defence reactions. Our results strongly support the interpretation that CfEC92 contributes to C. fructicola virulence as a plant immunity suppressor at the early infection phase.


Assuntos
Colletotrichum/patogenicidade , Proteínas Fúngicas/fisiologia , Malus/imunologia , Malus/microbiologia , Doenças das Plantas/microbiologia , Imunidade Vegetal , Morte Celular , Colletotrichum/genética , Colletotrichum/imunologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/imunologia , Regulação Fúngica da Expressão Gênica , Hospedeiro Imunocomprometido/imunologia , Células Vegetais , Doenças das Plantas/imunologia , Folhas de Planta/microbiologia , Regulação para Cima , Virulência
11.
Sci Total Environ ; 728: 138685, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32361113

RESUMO

Elemental sulfur recover from sulfate-rich environment has great significance for the sustainable development of environment and energy. This study aimed to realize simultaneous sulfate reduction and elemental sulfur recovery using a novel photoelectricity microbial electrolysis cell (PMEC) under low applied voltages. At an applied voltage of 1.2 V, the sulfate reduction rate in the PMEC reached 200 ± 2.3 mg L-1 d-1, and 46.3 ± 7.9% of the reduced sulfate converted to elemental sulfur. With increasing voltages from 0.8 to 1.5 V, the sulfate reduction rates enhanced from 37.8 ± 12.4 to 236 ± 18.1 mg L-1 d-1. The recovery efficiency of elemental sulfur from removed sulfate decreased to 35% at 1.5 V, which was attributed to the higher concentration of dissolved oxygen diffusing from the anode side. Sulfate reducing bacteria (including Desulfovibrio and Desulfomicrobium) cooperated with sulfur oxidizing bacteria (including Thiomonas and Acinetobacter) for recovering elemental sulfur that could be regulated by cathode configuration. The study provided an alternative to apply solar energy in biological sulfur recovery and reduce energy consumption of wastewater treatment.


Assuntos
Eletrólise , Enxofre , Reatores Biológicos , Oxirredução , Sulfatos , Águas Residuárias
12.
Chemosphere ; 251: 126381, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32443232

RESUMO

In this study, carbon quantum dots (CQDs) were used to decorate a TiO2/g-C3N4 (TCN) film electrode. The morphological, optical, and electrochemical properties of the TiO2/g-C3N4/CQDs nanorod arrays (TCNC NRAs) film were investigated using transmission electron microscopy (TEM), scanning electron microscopy (SEM), UV-vis diffuse reflectance spectroscopy (DRS), photoluminescence (PL), and electrochemical impedance spectroscopy (EIS). The improved optical properties, photoelectrochemical properties and photoelectrocatalytic (PEC) performance of photoanode can be observed by doping CQDs onto the TCN NRAs film. Compared with TiO2 NRAs and TCN NRAs, the narrower band gap of 2.47 eV and longer lifetime of photoinduced electron-hole pairs were observed in the TCNC NRAs. Under visible light irradiation and a bias voltage of 1.2 V, the photocurrent density and 1,4-dioxane (1,4-D) removal rate of PEC process with TCNC NRAs electrode reached 0.16 mA/cm2 and 77.9%, respectively, which was 2.5 times and 1.5 times of that with TCN NRAs electrode. TCNC NRAs electrode could keep >75% of the 1,4-D removal rate during five cycles tests. High PEC performance with TCNC NRAs electrode could be attributed to the enhanced charge separation and the change of electron transfer mechanism from typical heterojunction to Z-scheme, which may increase the active species production and change the dominant reactive species from O2·- to ·OH. Our experimental results should be useful for studying the degradation of 1,4-D and developing efficient PEC materials.


Assuntos
Dioxanos/química , Pontos Quânticos/química , Carbono , Eletrodos , Luz , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanotubos/química , Titânio
13.
Bioresour Technol ; 309: 123322, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32305841

RESUMO

Extracellular electron transfer (EET) is a significant pathway to transport electrons between bacteria and electrode in microbial electrosynthesis systems (MESs). To enhance EET in the MES, a high-conductivity polymer, polypyrrole (PPy), was coated on the surface of mixed culture acetogens in situ and the PPy-coated bacteria were inoculated on the cathode of MES. The charge transfer resistance of PPy-coated biocathode was 33%-70% of that with PPy-uncoated. Acetate production rate and Faradic efficiency in PPy-coated biocathodes increased by 3 to 6 times. After 960 h operation, Acetobacterium, Desulfovibrio, and Acinetobacter dominate the community on the coated and uncoated biocathode. Quinone loop and NADH dehydrogenase to ubiquinone were involved in electron transfer pathway of biocathode and stimulated by PPy coating. Low-level expression of C-type cytochromes on biocathode indicated its less important role in inward EET. The study provided useful information for applications of high-conductivity chemicals in microbial electrosynthesis.


Assuntos
Elétrons , Polímeros , Dióxido de Carbono , Eletrodos , Transporte de Elétrons , Pirróis
14.
J Ethnopharmacol ; 258: 112831, 2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32283192

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Prunus mira Koehne (P. mira, Tibetan name: ཁམབུ།) is a kind of medicinal plant commonly used in Tibetan areas. The classic Tibetan medicine book Jingzhu Materia Medica records that "the nut oil from P. mira is used to cure loss of hair, eyebrows, beards, etc." but the clinical experience has not been explored. Hair loss (alopecia) is a skin disease that becomes a common concern in Chinese society since it affects the appearance of a person. This paper studies the effectiveness of nut oil from P. mira in promoting hair growth and its working mechanism. MATERIALS AND METHODS: The content of different components in the nut oil from P. mira was determined by HPLC. Two hair removal methods (sodium sulfide and hair removal cream) were used to study the effect of different doses on hair growth in KM mice. Then select the effective group, and use C57BL/6 mice to determine the number of hair follicles, dermal thickness, ß-catenin, GSK3ß and Wnt10 b mRNA and protein expression. RESULTS: The contents of α-tocopherol, ß-sitosterol, Vitamin E, Oleic acid and linoleic acid in nut oil from P. mira growing in 12 different regions were determined by HPLC. The linearity reached 0.999. The RSD of precision, stability, repeatability, and sample recovery was less than 3%. The dose-effect relationship suggested that 30.13 and 14.07 mg medicinal material·(cm2·d)-1 oil promoted hair growth and the dose effect was positively correlated. 30.13 mg medicinal material·(cm2·d)-1 nut oil from P. mira can accelerate hair follicles into the anagen, increasing Wnt 10 b mRNA expression, ß-catenin mRNA and protein expression, and GSK-3 ß protein expression. CONCLUSION: This study improved the quality control of nut oil from P. mira and found that it has the effect of promoting hair growth in mice. The working mechanism may be related to Wnt/ß-catenin signaling pathway.


Assuntos
Folículo Piloso/efeitos dos fármacos , Cabelo/efeitos dos fármacos , Óleos Vegetais/farmacologia , Prunus/química , Alopecia/tratamento farmacológico , Animais , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Feminino , Glicogênio Sintase Quinase 3 beta/genética , Cabelo/crescimento & desenvolvimento , Folículo Piloso/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Óleos Vegetais/química , Óleos Vegetais/isolamento & purificação , Coelhos , Via de Sinalização Wnt/efeitos dos fármacos
15.
ACS Nano ; 14(5): 5233-5242, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32195582

RESUMO

Microscale intelligent actuators capable of sensitive and accurate manipulation under external stimuli hold great promise in various fields including precision sensors and biomedical devices. Current microactuators, however, are often limited to a multiple-step fabrication process and multimaterials. Here, a pH-triggered soft microactuator (<100 µm) with simple structure, one-step fabrication process, and single material is proposed, which is composed of deformable hydrogel microstructures fabricated by an asymmetric femtosecond Bessel beam. To further explore the swelling-shrinking mechanism, the hydrogel porosity difference between expansion and contraction states is investigated. In addition, by introducing the dynamic holographic processing and splicing processing method, more complex responsive microstructures (S-shaped, C-shaped, and tortile chiral structures) are rapidly fabricated, which exhibit tremendous expected deformation characteristics. Finally, as a proof of concept, a pH-responsive microgripper is fabricated for in situ capturing polystyrene (PS) particles and neural stem cells rapidly. This flexible, designable, and one-step approach manufacturing of intelligent actuator provides a versatile platform for micro-objects manipulation and drug delivery.


Assuntos
Hidrogéis
16.
J Vis Exp ; (155)2020 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-31984957

RESUMO

Biomedical optical imaging is playing an important role in diagnosis and treatment of various diseases. However, the accuracy and the reproducibility of an optical imaging device are greatly affected by the performance characteristics of its components, the test environment, and the operations. Therefore, it is necessary to calibrate these devices by traceable phantom standards. However, most of the currently available phantoms are homogeneous phantoms that cannot simulate multimodal and dynamic characteristics of biological tissue. Here, we show the fabrication of heterogeneous tissue-simulating phantoms using a production line integrating a spin coating module, a polyjet module, a fused deposition modeling (FDM) module, and an automatic control framework. The structural information and the optical parameters of a "digital optical phantom" are defined in a prototype file, imported to the production line, and fabricated layer-by-layer with sequential switch between different printing modalities. Technical capability of such a production line is exemplified by the automatic printing of skin-simulating phantoms that comprise the epidermis, dermis, subcutaneous tissue, and an embedded tumor.


Assuntos
Biomimética , Imagem Multimodal , Imagens de Fantasmas , Impressão Tridimensional , Automação , Simulação por Computador , Desenho Assistido por Computador , Derme/anatomia & histologia , Derme/diagnóstico por imagem , Epiderme/anatomia & histologia , Epiderme/diagnóstico por imagem , Humanos , Reprodutibilidade dos Testes , Tela Subcutânea/anatomia & histologia , Tela Subcutânea/diagnóstico por imagem
17.
Bioresour Technol ; 295: 122270, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31678890

RESUMO

Flexible control of CH4/H2 ratio in biohythane is important to its applications but remains a challenge. Herein, a dual-cathode bioelectrochemical system (BES) was developed for achieving biohythane production with controllable composition through adjusting external resistance. The BES was started as a microbial electrolysis cell to produce hydrogen in both cathodes ("H2-cathode") and then evolved to produce methane production in one cathode with inoculation of anaerobic sludge ("CH4-cathode"). When increasing the external resistance of the H2-cathode from 10 to 330 Ω, its H2 production decreased from 173 ±â€¯11 to 8 ±â€¯2 L m-3 d-1. This redistribution of electrons has benefited the CH4-cathode that had an increased CH4 production from 25 ±â€¯3 to 90 ±â€¯5 L m-3 d-1. The CH4/H2 ratio increased from 0.14 to 11, making biohythane more applicable to natural gas engines. Those results will help to formulate a BES-based approach to accomplish controllable biohythane production.


Assuntos
Hidrogênio , Metano , Eletrodos , Eletrólise , Esgotos
18.
Appl Opt ; 58(14): 3877-3885, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-31158206

RESUMO

Retinal vessel oxygen supply is important for retinal tissue metabolism. Commonly used retinal vessel oximetry devices are based on dual-wavelength spectral measurement of oxyhemoglobin and deoxyhemoglobin. However, there is no traceable standard for reliable calibration of these devices. In this study, we developed a fundus-simulating phantom that closely mimicked the optical properties of human fundus tissues. Microchannels of precisely controlled topological structures were produced by soft lithography to simulate the retinal vasculature. Optical properties of the phantom were adjusted by adding scattering and absorption agents to simulate different concentrations of fundus pigments. The developed phantom was used to calibrate the linear correlation between oxygen saturation (SO2) level and optical density ratio in a dual-wavelength oximetry device. The obtained calibration factors were used to calculate the retinal vessel SO2 in both eyes of five volunteers aged between 24 and 27 years old. The test results showed that the mean arterial and venous SO2 levels after phantom calibration were coincident with those after empirical value calibration, indicating the potential clinical utility of the produced phantom as a calibration standard.

19.
Oxid Med Cell Longev ; 2019: 5897675, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31178969

RESUMO

San-Huang-Xie-Xin decoction (SHXXD), composed of Rhei Radix et Rhizoma, Coptidis Rhizoma, and Scutellariae Radix, is a representative antipyretic and detoxifying prescription in traditional Chinese medicine. In this study, we investigated the antistress effects and underlying mechanisms of San-Huang-Xie-Xin decoction (SHXXD) on restraint-stressed mice by 1H NMR-based metabolomics combined with biochemistry assay. A total of 48 male mice (5 weeks old, 18-22 g) were divided randomly into 6 groups (n = 8), including the normal group, restraint-stressed group, vitamin C group (positive drug, 17 mg/kg), and 3-dosage groups of SHXXD (200, 400, and 800 mg/kg). The stress model was induced by restraining mice in a polypropylene centrifuge tube for 6 h every day. The rotarod test was performed, and several biochemical indicators were measured. Moreover, other 24 animals were divided into 3 groups (n = 8) including the normal group, restraint-stressed group, and SHXXD group (800 mg/kg) for 1H NMR-based metabolomics analysis. Our results showed that SHXXD significantly increased the rotarod time, thymus index, spleen index, and the levels of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and interleukin- (IL-) 2, but decreased the levels of malondialdehyde (MDA), IL-1ß, tumor necrosis factor- (TNF-) α, corticosterone (CORT), and adrenocorticotropic hormone (ACTH) in restraint-stressed mice. Moreover, the contents of eight endogenous metabolites that were changed by restraint stress were significantly reversed by SHXXD. The results of both metabolomics and biochemical analysis indicated that SHXXD (800 mg/kg, p.o.) could improve the biochemical changes and metabolic disorders in restraint-stressed mice by antioxidation and anti-inflammation, enhancing the body's immune function and restoring several disturbed metabolic pathways (i.e., lipid metabolism, glycolysis and gluconeogenesis, inflammatory injury, and energy metabolism). Taken together, these results indicated that SHXXD has a potential antistress effect in restraint-stressed mice and could be considered as a candidate drug for stress-related disorders.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa/métodos , Metabolômica/métodos , Estresse Psicológico/tratamento farmacológico , Animais , Medicamentos de Ervas Chinesas/farmacologia , Masculino , Camundongos
20.
Huan Jing Ke Xue ; 40(5): 2302-2309, 2019 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-31087870

RESUMO

Microbial electrosynthesis systems (MESs) can convert carbon dioxide into added value compounds using microorganisms as catalyst, which is expected to help achieve conversion of greenhouse gases into resources. However, the synthetic efficiency of MESs is far behind the industry requirements. In this study, carbon cloth surfaces were bonded with carboxyl groups by electrochemical reduction of aryl diazonium salts and then used as a cathode in MESs reactors. The results showed that the hydrophilicity of the carbon cloth surfaces improved after the carboxyl groups were modified. However, weaker current of cyclic voltammetry was obtained in the modified cathode. Significant differences were observed between modified (CA-H, CA-M, CA-L) and non-modified cathode (CK) during the start-up period. After 48h, the hydrogen production rate of CA-H, CA-M, CA-L was 21.45, 28.60, and 22.75 times higher than CK. After 120h, the acetate accumulation concentration of CA-H, CA-M, CA-L was 2.01, 2.43, and 1.44 times higher than CK. After 324h, there was little difference in the electrochemical activity of cathodic biofilm and protein content (about 0.47 mg·cm-2) in all groups. The analysis of the community structure of cathodic biofilm showed that, in the genus level, Acetobacterium, Norank_p_Saccharibacteria, and Thioclava were the dominant species, accounting for 59.6% to 82.1%. There was little difference in the relative abundance of Acetobacterium in all groups (31.3% to 40.1%). However, the relative abundance of norank_p_Saccharibacteria in CA-H, CA-M, CA-L, and CK were 16.1%, 24.6%, 31.1%, and 37.5%, respectively. The carboxyl modified cathode had a great influence on the start-up stage of MESs, which could be a new idea for the rapid start-up of MESs.

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