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1.
Langmuir ; 40(22): 11635-11641, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38775800

RESUMO

The presence of abnormal dopamine (DA) levels may cause serious neurological disorders, therefore, the quantitative analysis of DA and its related research are of great significance for ensuring health. Herein, the bovine serum albumin (BSA) template method has been proposed for the preparation of catalytically high-performance ruthenium dioxide/multiwalled carbon nanotube (RuO2/MWCNT) nanocomposites. The incorporation of MWCNTs has improved the active surface area and conductivity while effectively preventing the aggregation of RuO2 nanoparticles. The outstanding electrocatalytic performance of RuO2/MWCNTs has promoted the electro-oxidation of DA at neutral pH. The electrochemical sensing platform based on RuO2/MWCNTs has demonstrated a wide linear range (0.5 to 111.1 µM), low detection limit (0.167 µM), excellent selectivity, long-term stability, and good reproducibility for DA detection. The satisfactory recovery range of 94.7% to 103% exhibited by the proposed sensing podium in serum samples signifies its potential for analytical applications. The aforementioned results reveal that RuO2/MWCNT nanostructures hold promising aptitude in the electrochemical sensor to detect DA in real samples, further offering broad prospects in clinical and medical diagnosis.


Assuntos
Técnicas Biossensoriais , Dopamina , Técnicas Eletroquímicas , Nanotubos de Carbono , Compostos de Rutênio , Soroalbumina Bovina , Nanotubos de Carbono/química , Dopamina/sangue , Dopamina/análise , Dopamina/química , Humanos , Técnicas Biossensoriais/métodos , Soroalbumina Bovina/química , Técnicas Eletroquímicas/métodos , Compostos de Rutênio/química , Animais , Bovinos , Limite de Detecção
2.
Talanta ; 275: 126141, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38677168

RESUMO

The crucial cellular activities for maintaining normal cell functions heavily rely on the polarity of the endoplasmic reticulum (ER). Understanding how the polarity shifts, particularly in the context of ER autophagy (ER-phagy), holds significant promise for advancing knowledge of disorders associated with ER stress. Herein, a polarity-sensitive fluorescent probe CDI was easily synthesized from the condensation reaction of coumarin and dicyanoisophorone. CDI was composed of coumarin as the electron-donating moiety (D), ethylene and phenyl ring as the π-conjugation bridge, and malononitrile as the electron-accepting moiety (A), forming a typical D-π-A molecular configuration that recognition in the near-infrared (NIR) region. The findings suggested that as the polarity increased, the fluorescence intensity of CDI decreased, and it was accompanied by a redshift of emission wavelength at the excitation wavelength of 524 nm, shifting from 641 nm to 721 nm. Significantly, CDI exhibited a notable ability to effectively target ER and enabled real-time monitoring of ER-phagy induced by starvation or drugs. Most importantly, alterations in polarity can be discerned through in vivo imaging in mice model of rheumatoid arthritis (RA). CDI has been proven effective in evaluating the therapeutic efficacy of drugs for RA. ER fluorescent probe CDI can be optically activated in lysosomes, providing a sensitive tool for studying ER-phagy in biology and diseases.


Assuntos
Artrite Reumatoide , Autofagia , Retículo Endoplasmático , Corantes Fluorescentes , Animais , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Retículo Endoplasmático/metabolismo , Autofagia/efeitos dos fármacos , Camundongos , Artrite Reumatoide/diagnóstico por imagem , Artrite Reumatoide/patologia , Artrite Reumatoide/metabolismo , Imagem Óptica , Humanos , Cumarínicos/química , Cumarínicos/síntese química , Raios Infravermelhos
3.
Asian J Pharm Sci ; 19(2): 100886, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38590795

RESUMO

Neurological injury caused by ischemic stroke is a major cause of permanent disability and death. The currently available neuroprotective drugs fail to achieve desired therapeutic efficacy mainly due to short circulation half-life and poor blood-brain barrier (BBB) permeability. For that, an edaravone-loaded pH/glutathione (pH/GSH) dual-responsive poly(amino acid) nanogel (NG/EDA) was developed to improve the neuroprotection of EDA. The nanogel was triggered by acidic and EDA-induced high-level GSH microenvironments, which enabled the selective and sustained release of EDA at the site of ischemic injury. NG/EDA exhibited a uniform sub-spherical morphology with a mean hydrodynamic diameter of 112.3 ± 8.2 nm. NG/EDA efficiently accumulated at the cerebral ischemic injury site of permanent middle cerebral artery occlusion (pMCAO) mice, showing an efficient BBB crossing feature. Notably, NG/EDA with 50 µM EDA significantly increased neuron survival (29.3%) following oxygen and glucose deprivation by inhibiting ferroptosis. In addition, administering NG/EDA for 7 d significantly reduced infarct volume to 22.2% ± 7.2% and decreased neurobehavioral scores from 9.0 ± 0.6 to 2.0 ± 0.8. Such a pH/GSH dual-responsive nanoplatform might provide a unique and promising modality for neuroprotection in ischemic stroke and other central nervous system diseases.

4.
Plant Cell Environ ; 47(4): 1379-1396, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38221869

RESUMO

Japanese apricot is an important subtropical deciduous fruit tree in China, widely distributed in different altitude areas. How does it adapt to the different temperature environments in these areas? In this study, we identified a low-temperature transcription factor PmCBF03 on chromosome 7 through adaptive analysis of populations at different altitudes, which has an early termination single nucleotide polymorphism mutation. There were two different types of variation, PmCBF03A type in high-altitude areas and PmCBF03T type in low-altitude areas. PmCBF03A gene increased the survival rate, Fv/Fm values, antioxidant enzyme activity, and expression levels of antioxidant enzyme genes, and reducing electrolyte leakage and accumulation of reactive oxygen species in transgenic Arabidopsis under low temperature and freezing stress. Simultaneously, PmCBF03A gene promoted the dormancy of transgenic Arabidopsis seeds than wild-type. Biochemical analysis demonstrated that PmCBF03A directly bound to the DRE/CRT element in the promoters of the PmCOR413, PmDAM6 and PmABI5 genes, promoting their transcription and enhanced the cold resistance and dormancy of the overexpressing PmCBF03A lines. While PmCBF03T gene is unable to bind to the promoters of PmDAM6 and PmABI5 genes, leading to early release of dormancy to adapt to the problem of insufficient chilling requirement in low-altitude areas.


Assuntos
Arabidopsis , Prunus armeniaca , Prunus , Temperatura , Frutas , Altitude , Prunus/genética , Prunus/metabolismo , Antioxidantes/metabolismo , Arabidopsis/genética
5.
Health Psychol Behav Med ; 11(1): 2278290, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37936634

RESUMO

Objective: This study is the first to examine the relationship between character strengths, objective physical fitness, and physical activity in primary school children. Design: This cross-sectional study was conducted in 2016 and 2017 at a school in Japan. Main Outcome Measures: We obtained informed consent from 236 fourth-grade students; 122 fifth-grade students; and 142 sixth-grade students. After excluding participants with missing data, 473 children (247 boys and 226 girls; aged 9-12 years) with informed consent were included in the study. We measured character strengths, physical fitness, and/or physical activity of fourth- to sixth-grade participants. Results: Among boys, the total score of physical fitness was significantly associated with perseverance-honesty, courage-ideas, compassion-gratitude, and fairness-care (p < 0.05). Among girls, the total score of physical fitness was significantly associated with perseverance-honesty, courage-ideas, and compassion-gratitude (p < 0.05). Regarding the relationship between character strengths and physical activity, perseverance-honesty was significantly associated with total steps and moderate-to-vigorous physical activity (MVPA), whereas courage ideas were significantly associated with total steps (p < 0.05) in boys. In girls, perseverance-honesty was associated with MVPA (p < 0.05). Conclusions: Our findings revealed that character strengths are positively associated with objective physical fitness and physical activity in primary-school children.

6.
Spectrochim Acta A Mol Biomol Spectrosc ; 303: 123179, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37542874

RESUMO

Although peroxynitrite (ONOO-) plays an essential role in cellular redox homeostasis, its excess ONOO- will affect the normal physiological function of cells. Therefore, real-time monitoring of changes in local ONOO- will contribute to further revealing the biological functions. Reliable and accurate detection of biogenic ONOO- will definitely benefit for disentangling its complex functions in living systems. In the past few years, more fluorescent probes have been developed to help understand and reveal cellular ONOO- changes. However, there has been no comprehensive and critical review of multifunctional fluorescent probes for cellular ONOO- and other analytes. To highlight the recent advances, this review first summarized the recent progress of multifunctional fluorescent probes since 2018, focusing on molecular structures, response mechanisms, optical properties, and biological imaging in the detection and imaging of cellular ONOO- and analytes. We classified and discussed in detail the limitations of existing multifunctional probes, and proposed new ideas to overcome these limitations. Finally, the challenges and future development trends of ONOO- fluorescence probes were discussed. We hoped this review will provide new research directions for developing of multifunctional fluorescent probes and contribute to the early diagnosis and treatment of diseases.


Assuntos
Corantes Fluorescentes , Ácido Peroxinitroso , Corantes Fluorescentes/química , Estrutura Molecular , Imagem Óptica
7.
Chem Rev ; 123(17): 10530-10583, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37589482

RESUMO

Electrosynthesis of value-added chemicals, directly from CO2, could foster achievement of carbon neutral through an alternative electrical approach to the energy-intensive thermochemical industry for carbon utilization. Progress in this area, based on electrogeneration of multicarbon products through CO2 electroreduction, however, lags far behind that for C1 products. Reaction routes are complicated and kinetics are slow with scale up to the high levels required for commercialization, posing significant problems. In this review, we identify and summarize state-of-art progress in multicarbon synthesis with a multiscale perspective and discuss current hurdles to be resolved for multicarbon generation from CO2 reduction including atomistic mechanisms, nanoscale electrocatalysts, microscale electrodes, and macroscale electrolyzers with guidelines for future research. The review ends with a cross-scale perspective that links discrepancies between different approaches with extensions to performance and stability issues that arise from extensions to an industrial environment.

8.
Anal Chem ; 95(27): 10155-10162, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37376771

RESUMO

Abnormal changes occurring in the mitochondrial microenvironment are important markers indicating mitochondrial and cell dysfunction. Herein, we designed and synthesized a multifunctional fluorescent probe DPB that responds to polarity, viscosity, and peroxynitrite (ONOO-). DPB is composed of an electron donor (diethylamine group) and electron acceptor (coumarin, pyridine cations, and phenylboronic acid esters), in which the pyridine group with a positive charge is responsible for targeting to mitochondria. D-π-A structure with strong intramolecular charge transfer (ICT) and twisted intramolecular charge transfer (TICT) properties give rise to respond to polarity and viscosity. The introduction of cyanogroup and phenylboronic acid esters increases the electrophilicity of the probe, which is prone to oxidation triggered by ONOO-. The integrated architecture satisfies the multiple response requirements. As the polarity increases, the fluorescence intensity of probe DPB at 470 nm is quenched by 97%. At 658 nm, the fluorescence intensity of DPB increases with viscosity and decreases with the concentration of ONOO-. Furthermore, the probe is not only successfully used to monitor mitochondrial polarity, viscosity, and endogenous/exogenous ONOO- level fluctuations but also to distinguish cancer cells from normal cells by multiple parameters. Therefore, as-prepared probe provides a reliable tool for better understanding of the mitochondrial microenvironment and also a potential approach for the diagnosis of disease.


Assuntos
Corantes Fluorescentes , Mitocôndrias , Corantes Fluorescentes/química , Viscosidade , Mitocôndrias/química , Microscopia de Fluorescência/métodos , Imagem Óptica/métodos , Piridinas/análise , Ácido Peroxinitroso/análise
9.
ACS Biomater Sci Eng ; 9(6): 3581-3589, 2023 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-37252846

RESUMO

Irregularities in mitochondrial viscosity and peroxynitrite (ONOO-) concentration can lead to mitochondrial dysfunction. It is still a great challenge to develop near-infrared (NIR) fluorescent probes to simultaneously detect viscosity, endogenous ONOO-, and mitophagy. Herein, a multifunctional mitochondria-targeting NIR fluorescent probe P-1 was first synthesized for simultaneously detecting viscosity, ONOO-, and mitophagy. P-1 used quinoline cations as a mitochondrial targeting moiety, arylboronate as an ONOO- responsive group, and detected the change of viscosity by the twisted internal charge transfer (TICT) mechanism. The probe has an excellent response to the viscosity during inflammation by lipopolysaccharides (LPSs) and mitophagy induced by starvation at 670 nm. The viscosity changes of the probe induced by nystatin in zebrafish showed that P-1 was able to detect microviscosity in vivo. P-1 also showed good sensitivity with a detection limit of 6.2 nM for ONOO- detection and was successfully applied to the endogenous ONOO- detection in zebrafish. Moreover, P-1 has the ability to distinguish between cancer cells and normal cells. All of these features make P-1 a promising candidate to detect mitophagy and ONOO- -associated physiological and pathological processes.


Assuntos
Mitocôndrias , Mitofagia , Viscosidade , Mitocôndrias/química , Espectroscopia de Luz Próxima ao Infravermelho , Corantes Fluorescentes/química , Ácido Peroxinitroso/química , Animais , Peixe-Zebra
10.
Opt Lett ; 48(6): 1502-1505, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36946963

RESUMO

Mid-infrared dielectric metasurfaces are promising fundamental building blocks for integrated sensing with high sensitivity, compositional selectivity, and low loss. We have designed and fabricated a silicon metasurface with resonance properties in the 4∼5 µm mid-infrared region and a volume enhancement of up to 9 times. Benchmark FTIR characterizations of solutions of tungsten hexacarbonyl molecules showed a detection limit of 1 mg/mL without the usage of surface enrichment treatment. We further rationalize the detection limit of the molecules-nanostructure open interface with volume field enhancement analysis. Our results show that mid-infrared silicon metasurfaces may be a suitable platform for potential integration with microfluidic for in vivo detection.

11.
Neuroscience ; 520: 134-143, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36716913

RESUMO

Tibetans have adapted to high altitude environments. However, the genetic effects in their brains have not been identified. Twenty-five native Tibetans living in Lhasa (3650 m) were recruited for comparison with 20 Han immigrants who originated from lowlands and had been living in Lhasa for two years. The physiological characteristics, brain structure and neuronal spontaneous activity were investigated. Compared with Han immigrants, Tibetans showed higher peripheral oxygen saturation (SpO2), and lower heart rate, red blood cell counts, hematocrit, and hemoglobin. Tibetans showed increased gray matter volume in the visual cortex, hippocampus, and rectus; increased the amplitudes of low-frequency fluctuations (ALFF) values in the left putamen and left fusiform gyrus; and decreased voxel-mirrored homotopic connectivity (VMHC) values in the precentral gyrus. Moreover, Tibetans have decreased functional connectivity (FC) between the left precentral gyrus and the frontal gyrusand right precuneus. In Tibetans and Han immigrants, hemoglobin and hematocrit were negatively correlated with total gray matter volume in males, SpO2 was also positively correlated with ALFF in the left fusiform gyrus, while hemoglobin, and hematocrit were positively correlated with VMHC in the precentral gyrus and FC in the precentral gyrus with other brain regions, SpO2 was also found to be negatively correlated with VMHC in the precentral gyrus, and hemoglobin and hematocrit were negatively correlated with ALFF in the left putamen and left fusiform gyrus. In summary, genetic mutations may result in modulation of some brain regions, which was further confirmed by the identification of correlations with hemoglobin and hematocrit in these regions.


Assuntos
Altitude , Imageamento por Ressonância Magnética , Masculino , Humanos , Tibet , Encéfalo/diagnóstico por imagem , Hemoglobinas
12.
Proc Natl Acad Sci U S A ; 120(4): e2214175120, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36649419

RESUMO

Copper is distinctive in electrocatalyzing reduction of CO2 into various energy-dense forms, but it often suffers from limited product selectivity including ethanol in competition with ethylene. Here, we describe systematically designed, bimetallic electrocatalysts based on copper/gold heterojunctions with a faradaic efficiency toward ethanol of 60% at currents in excess of 500 mA cm-2. In the modified catalyst, the ratio of ethanol to ethylene is enhanced by a factor of 200 compared to copper catalysts. Analysis by ATR-IR measurements under operating conditions, and by computational simulations, suggests that reduction of CO2 at the copper/gold heterojunction is dominated by generation of the intermediate OCCOH*. The latter is a key contributor in the overall, asymmetrical electrohydrogenation of CO2 giving ethanol rather than ethylene.

13.
Spectrochim Acta A Mol Biomol Spectrosc ; 290: 122267, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36566535

RESUMO

The in vivo detection of biomarkers in a liquid environment is very important for the early diagnosis of diseases. Spectroscopy methods are employed in ultraviolet-visible-infrared wavelengths, fluorescence or Raman spectra are detected for clinical diagnose. The dual-mode image can provide more diagnostic information and has been realized in some research work. However, there is still lacking simple and sensitive dual-mode sensors to satisfy the in vivo detecting demands. In this paper, a dual-mode fiber sensor for Surface-enhanced Raman Scattering (SERS) and fluorescence detection is proposed. The sensor is formed by a tapered optical fiber, half of the fiber tip surface is coated with Ag nanoparticles. In the detection of Rhodamine 6G (R6G) aqueous solution, the minimum detectable concentrations in SERS and fluorescence tests are of the same order of magnitude. By combining the Raman spectral features and the fluorescence intensity, the recognition and quantitation of target molecules were obtained reliably. It is the first time, to our knowledge, that the Raman-fluorescence dual-mode detection is realized in one single fiber, which was manufactured with micro-machinery techniques. It is a label-free, general-purpose fiber sensor, which can be applied for liquid biopsy, helping to diagnose and treat diseases in vivo.


Assuntos
Nanopartículas Metálicas , Fibras Ópticas , Nanopartículas Metálicas/química , Prata/química , Análise Espectral Raman/métodos
14.
Cell Mol Neurobiol ; 43(5): 2273-2288, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36355226

RESUMO

Cognitive dysfunction and brain white matter (WM) injury have been found in adults exposed to hypoxia. However, the mechanisms underlying these impairments remain unclear, and moreover, it is also unclear whether these impairments are reversible after reoxygenation. In this study, adult male mice were exposed to hypoxia for 15 days at a simulated altitude of 4300 m and then reoxygenated for 2 months. Control mice were raised under normoxic conditions. Mice showed a significant decrease in arterial oxygen saturation (SaO2) and an increase in heart rate and breath rate after hypoxic exposure, and they displayed anxiety-like emotion and impaired cognitions. Hypoxic mice showed decreased brain WM fractional anisotropy (FA) and increased mean diffusion (MD) mainly in the corpus callosum and internal capsule. The reason for the adult brain WM injury was myelin rather than axon. Further, the myelin injury was due to the obstruction of oligodendrocyte precursor cells (OPCs) differentiation and eventually led to behavioral deficits. More importantly, the changes in physiological indicators, behavioral disorders, and WM injury caused by hypoxia can be recovered after reoxygenation. Taken together, our data indicate that adult brain WM injury caused by hypoxia is reversible after reoxygenation and enhancing OPCs differentiation may be a promising therapy for clinical hypoxic diseases associated with brain injury. Schematic diagram of brain WM and behavioral changes induced by hypoxia/reoxygenation in adult mice.


Assuntos
Lesões Encefálicas , Substância Branca , Animais , Masculino , Camundongos , Substância Branca/patologia , Encéfalo/patologia , Hipóxia/complicações , Hipóxia/patologia , Imageamento por Ressonância Magnética , Lesões Encefálicas/patologia
15.
Anal Methods ; 14(41): 4122-4126, 2022 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-36219148

RESUMO

A rapid method for the determination of ethanol content is proposed and tested. A fluorescence detecting system, with a multimode fiber (MMF) sensing head, is employed. Rhodamine 6G (R6G) is applied as the fluorescent indicator. In the R6G aqueous solution, the molecules aggregate at high concentration, causing fluorescence quenching. Nevertheless, aggregation and quenching rarely occur in ethanol. Taking an ethanol and water mixture as the solvent, the photoluminescence (PL) intensity reflects the aggregation degree and the ethanol content. Based on this phenomenon, the contents of the ethanol-water mixture were measured through PL intensity detection. A limit of detection (LOD) at ∼0.1 vol% level was obtained in the range of 0-100%. Commercial Chinese baijiu and rubbing alcohol were tested and the results obtained were consistent with the label values. The detecting system is compact and of low-cost, and the detecting method is rapid, accurate and repeatable. There is good prospect of applications for the determination of ethanol content on-site.


Assuntos
Fibras Ópticas , Água , Rodaminas , Etanol
16.
Toxins (Basel) ; 14(8)2022 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-35893751

RESUMO

Deoxynivalenol (DON) and emerging Alternaria toxins often co-occur in cereal-based products, but the current risk assessment is commonly conducted for only one type of mycotoxin at a time. Compared to adults, infants and young children are more susceptible to mycotoxins through food consumption, especially with cereal-based food products which are the main source of exposure. This study aimed to perform a probabilistic risk assessment of combined exposure to DON and three major Alternaria toxins, namely including alternariol monomethyl ether (AME), alternariol (AOH), and tenuazonic acid (TeA) through consumption of cereal-based foods for Chinese infants and young children. A total of 872 cereal-based food products were randomly collected and tested for the occurrence of DON and three major Alternaria toxins. The results on mycotoxin occurrence showed the DON, TeA, AOH, and AME was detected in 56.4%, 47.5%, 7.5%, and 5.7% of the samples, respectively. Co-contamination of various mycotoxins was observed in 39.9% of the analyzed samples. A preliminary cumulative risk assessment using the models of hazard index (HI) and combined margin of exposure (MoET) was performed on DON and Alternaria toxins that were present in cereal-based food products for infants and young children in China for the first time. The results showed that only 0.2% and 1.5%, respectively, of individuals exceeded the corresponding reference value for DON and TeA, indicating a low health risk. However, in the case of AME and AOH, the proportion of individuals exceeding the reference value was 24.1% and 33.5%, respectively, indicating the potential health risks. In the cumulative risk assessment of AME and AOH, both HI and MoET values indicated a more serious risk than that related to individual exposure. Further research is necessary to reduce the uncertainties that are associated with the toxicities of the Alternaria toxins and cumulative risk assessment methods.


Assuntos
Alternaria , Grão Comestível , Contaminação de Alimentos , Tricotecenos , Alternaria/isolamento & purificação , Pré-Escolar , China , Grão Comestível/química , Grão Comestível/microbiologia , Contaminação de Alimentos/análise , Humanos , Lactente , Lactonas/análise , Micotoxinas/análise , Medição de Risco , Ácido Tenuazônico/análise , Tricotecenos/análise
17.
Brain Sci ; 12(6)2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35741609

RESUMO

Damage to the visual cortex structures after high altitude exposure has been well clarified. However, changes in the neuronal activity and functional connectivity (FC) of the visual cortex after hypoxia/reoxygenation remain unclear. Twenty-three sea-level college students, who took part in 30 days of teaching at high altitude (4300 m), underwent routine blood tests, visual behavior tests, and magnetic resonance imaging scans before they went to high altitude (Test 1), 7 days after they returned to sea level (Test 2), as well as 3 months (Test 3) after they returned to sea level. In this study, we investigated the hematological parameters, behavioral data, and spontaneous brain activity. There were significant differences among the tests in hematological parameters and spontaneous brain activity. The hematocrit, hemoglobin concentration, and red blood cell count were significantly increased in Test 2 as compared with Tests 1 and 3. As compared with Test 1, Test 3 increased amplitudes of low-frequency fluctuations (ALFF) in the right calcarine gyrus; Tests 2 and 3 increased ALFF in the right supplementary motor cortex, increased regional homogeneity (ReHo) in the left lingual gyrus, increased the voxel-mirrored homotopic connectivity (VMHC) value in the motor cortex, and decreased FC between the left lingual gyrus and left postcentral gyrus. The color accuracy in the visual task was positively correlated with ALFF and ReHo in Test 2. Hypoxia/reoxygenation increased functional connection between the neurons within the visual cortex and the motor cortex but decreased connection between the visual cortex and motor cortex.

18.
Appl Biochem Biotechnol ; 194(11): 5255-5273, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35731444

RESUMO

High concentrations of fermentable sugars are a demand for economical bioethanol production. A single process strategy cannot comprehensively solve the limiting factors in high-solid enzymatic hydrolysis. The multiple intensification strategies in this study achieved the goal of preparing high-concentration fermentable sugars of corn stalk with high solid loading and low enzyme loading. First, steam explosion pretreatment enhanced the hydrophilicity of substrates and enzymatic accessibility. Second, periodic peristalsis was used to improve the mass transfer efficiency and short the liquefaction time. Additionally, fed-batch feeding and enzyme reduced the enzyme loading. Ultimately, the intensification strategies above showed that the highest fermentable sugar content was 313.8 g/L with a solids loading as much as 50% (w/w) and enzyme loading as low as 12.5 FPU/g DM. Thus, these multiple intensification strategies were promising in the high-solid enzymatic hydrolysis of steam-exploded lignocellulose.


Assuntos
Vapor , Açúcares , Hidrólise , Peristaltismo
19.
ACS Appl Bio Mater ; 5(6): 2777-2785, 2022 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-35574830

RESUMO

ONOO- is mainly produced in mitochondria, and dysfunctional and damaged mitochondria are degraded in lysosomes through autophagy, so it is important to synthesize a single probe for dual detection of ONOO- and mitophagy. Unfortunately, mitochondria-immobilized fluorescent probes for dual detection of ONOO- and mitophagy have not yet been developed. Hence, we first reported a piperazine-based mitochondria-immobilized red-emitting fluorescent probe (PMR), which not only can detect ONOO- but also could be used to image cellular mitophagy by the pH variations because of the protonation of the piperazine moiety. PMR was designed and prepared by introducing a piperazine ring as the pH response group, a lipophilic cation as the targeting mitochondria moiety, and benzyl chloride for immobilizing mitochondrial proteins through thiol groups. PMR displayed an enhanced fluorescence response at 640 nm through mitochondrial acidification. Using these advantages of PMR, which was successfully used for visualizing the mitophagy process induced by rapamycin or starvation, and chloroquine can inhibit rapamycin-induced mitophagy and prevent the fusion of autophagosomes and lysosomes. PMR also showed good sensitivity with a detection limit of 23 nM to ONOO-, which was successfully applied in imaging exogenous/endogenous ONOO-. Combining the above design, PMR may be used to study the detailed function of the mitophagy and ONOO--associated physiological and pathological processes.


Assuntos
Corantes Fluorescentes , Mitofagia , Corantes Fluorescentes/metabolismo , Concentração de Íons de Hidrogênio , Mitocôndrias/metabolismo , Piperazina/metabolismo , Sirolimo/metabolismo
20.
AAPS PharmSciTech ; 23(5): 126, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35474151

RESUMO

Obtaining a homogeneous low-dose pharmaceutical powder blend without multi-step processing remains a challenge. One promising technology to address this risk is resonant acoustic mixing (RAM). In this study, the performance of a laboratory resonant acoustic mixer (LabRAM) was studied at low active pharmaceutical ingredient (API) concentrations (0.1-0.5% w/w), using three commercial grades of a model API (Acetaminophen) and diluents with varying physical properties. The performance was assessed by evaluating blend uniformity (BU) and capsule content uniformity (CU) as a function of mixing time. Overall, the LabRAM achieved acceptable BU in a single step even at 0.1% w/w drug loading. A reduction in API primary particle size led to improved mixing efficiency and uniformity. Moreover, the presence of surface cavities in the diluents used appeared to have led to improved uniformity. The results demonstrated that RAM could achieve uniform powder blends without multi-step processing, for low-dose formulations.


Assuntos
Acústica , Excipientes , Composição de Medicamentos/métodos , Tamanho da Partícula , Pós
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