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ETHNOPHARMACOLOGICAL RELEVANCE: Viral pneumonia is the leading cause of death after SARS-CoV-2 infection. Despite effective at early stage, long-term treatment with glucocorticoids can lead to a variety of adverse effects and limited benefits. The Chinese traditional herb Pogostemonis Herba is the aerial part of Pogostemon Cablin (Blanco) Benth., which has potent antiviral, antibacterial, anti-inflammatory, and anticancer effects. It was used widely for treating various throat and respiratory diseases, including COVID-19, viral infection, cough, allergic asthma, acute lung injury and lung cancer. AIM OF THE STUDY: To investigate the antiviral and anti-inflammatory effects of chemical compounds from Pogostemonis Herba in SARS-CoV-2-infected hACE2-overexpressing mouse macrophage RAW264.7 cells and hACE2 transgenic mice. MATERIALS AND METHODS: The hACE2-overexpressing RAW264.7 cells were exposed with SARS-CoV-2. The cell viability was detected by CCK8 assay and cell apoptotic rate was by flow cytometric assay. The expressions of macrophage M1 phenotype markers (TNF-α and IL-6) and M2 markers (IL-10 and Arg-1) as well as the viral loads were detected by qPCR. The mice were inoculated intranasally with SARS-CoV-2 omicron variant to induce viral pneumonia. The levels of macrophages, neutrophils, and T cells in the lung tissues of infected mice were analyzed by full spectrum flow cytometry. The expressions of key proteins were detected by western blot assay. RESULTS: Diosmetin-7-O-ß-D-glucopyranoside (DG) presented the strongest anti-SARS-CoV-2 activity. Intervention with DG at the concentrations of 1.25-50 µM not only reduced the viral replication, cell apoptosis, and the productions of inflammatory cytokines (IL-6 and TNF-α) in SARS-CoV-2-infected RAW264.7 cells, but also reversed macrophage polarity from M1 to M2 phenotype. Furthermore, treatment with DG (25-100 mg/kg) alleviated acute lung injury, and reduced macrophage infiltration in SARS-COV-2-infected mice. Mechanistically, DG inhibited SARS-COV-2 gene expression and HK3 translation via targeting YTHDF1, resulting in the inactivation of glycolysis-mediated NF-κB pathway. CONCLUSIONS: DG exerted the potent antiviral and anti-inflammatory activities. It reduced pneumonia in SARS-COV-2-infected mice via inhibiting the viral replication and accelerating M2 macrophage polarization via targeting YTHDF1, indicating its potential for COVID-19 treatment.
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Colorectal cancer (CRC) is a common malignancy affecting the gastrointestinal tract worldwide. The etiology and progression of CRC are related to factors such as environmental influences, dietary structure, and genetic susceptibility. Intestinal microbiota can influence the integrity of the intestinal mucosal barrier and modulate intestinal immunity by secreting various metabolites. Dysbiosis of the intestinal microbiota can affect the metabolites of the microbial, leading to the accumulation of toxic metabolites, which can trigger chronic inflammation or DNA damage and ultimately lead to cellular carcinogenesis and the development of CRC. Postbiotics are preparations of inanimate microorganisms or their components that are beneficial to the health of the host, with the main components including bacterial components (e.g., exopolysaccharides, teichoic acids, surface layer protein) and metabolites (e.g., short-chain fatty acids, tryptophan metabolite, bile acids, vitamins and enzymes). Compared with traditional probiotics, it has a more stable chemical structure and higher safety. In recent years, it has been demonstrated that postbiotics are involved in regulating intestinal microecology and improving the progression of CRC, which provides new ideas for the prevention and diagnosis of CRC. In this article, we review the changes in intestinal microbiota in different states of the gut and the mechanisms of anti-tumor activity of postbiotic-related components, and discuss the potential significance of postbiotics in the diagnosis and treatment of CRC. This reviews the changes and pathogenesis of intestinal microbiota in the development of CRC, and summarizes the relevant mechanisms of postbiotics in resisting the development of CRC in recent years, as well as the advantages and limitations of postbiotics in the treatment process of CRC.
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Diabetic retinopathy (DR) is a prevalent microvascular complication in diabetic patients that poses a serious risk as it can cause substantial visual impairment and even vision loss. Due to the prolonged onset of DR, lengthy treatment duration, and limited therapeutic effectiveness, it is extremely important to find a new strategy for the treatment of DR. Postbiotic is an emerging dietary supplement which consists of the inactivate microbiota and its metabolites. Numerous animal experiments have demonstrated that intervention with postbiotics reduces hyperglycemia, attenuates retinal peripapillary and endothelial cell damage, improves retinal microcirculatory dysfunction, and consequently delays the progression of DR. More strikingly, unlike conventional probiotics and prebiotics, postbiotics with small molecules can directly colonize the intestinal epithelial cells, and exert heat-resistant, acid-resistant, and durable for storage. Despite few clinical significance, oral administration with postbiotics might become the effective management for the prevention and treatment of DR. In this review, we summarized the basic conception, classification, molecular mechanisms, and the advances in the therapeutic implications of postbiotics in the pathogenesis of DR. Postbiotics present great potential as a viable adjunctive therapy for DR.
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Plant-derived exosome-like nanoparticles (ELNs) have been proposed as a novel therapeutic tool for preventing human diseases. However, the number of well-verified plant ELNs remains limited. In this study, the microRNAs in ELNs derived from fresh Rehmanniae Radix, a well-known traditional Chinese herb for treating inflammatory and metabolic diseases, were determined by using microRNA sequencing to investigate the active components in the ELNs and the protection against lipopolysaccharide (LPS)-induced acute lung inflammation in vivo and in vitro. The results showed that rgl-miR-7972 (miR-7972) was the main ingredient in ELNs. It exerted stronger protective activities against LPS-induced acute lung inflammation than catalpol and acteoside, which are two well-known chemical markers in this herb. Moreover, miR-7972 decreased the production of pro-inflammatory cytokines (IL-1ß, IL-6, and TNF-α), reactive oxygen species (ROS) and nitric oxide (NO) in LPS-exposed RAW264.7 cells, thereby facilitating M2 macrophage polarization. Mechanically, miR-7972 downregulated the expression of G protein-coupled receptor 161 (GPR161), activating the Hedgehog pathway, and inhibited the biofilm form of Escherichia coli via targeting virulence gene sxt2. Therefore, miR-7972 derived from fresh R. Radix alleviated LPS-induced lung inflammation by targeting the GPR161-mediated Hedgehog pathway, recovering gut microbiota dysbiosis. It also provided a new direction for gaining novel bioactivity nucleic acid drugs and broadening the knowledge on cross-kingdom physiological regulation through miRNAs.
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Lesão Pulmonar Aguda , MicroRNAs , Pneumonia , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Lipopolissacarídeos/efeitos adversos , Disbiose/tratamento farmacológico , Proteínas Hedgehog , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/metabolismo , Pneumonia/genéticaRESUMO
A simple and sensitive method using in vivo microdialysis coupled with UPLC-MS/MS was established to evaluate the pharmacokinetics of Shuang Hu tincture (SHZTN). Xevo TQ-S was used to analyze the active ingredients of mesaconitine, hypaconitine, 4-hydroxycinnamic acid, ferulic acid and N-(2, 3-dimethyl phenyl)-2- aminobenzoic acid of SHZTN. Samples were prepared using a methanol precipitation method and the internal standards lannaconitine and p-hydroxybenzoic acid were added. The method validation was conducted according to the guidelines of the Pharmacopoeia of China. A good linear range was obtained in the range of 1-2,000 ng/ml. The intra-day and inter-day precisions were less than 14.7%, and the accuracy range of all the analytes was -10.5-9.3%. The recovery of each analyte was over 95.5%, and matrix effects can be neglected. After a single dose of 20 mg/kg SHZTN, the area under the curve and peak concentration of the five active ingredients were significantly increased by transdermal compared with oral administration, which indicated the high bioavailability of SHZTN. The time to peak concentration of all compounds was <3.4 h, and the half-life was <15.4 h, which indicated that the five compounds have the best absorption and rapid elimination. The method was successfully developed and applied to the pharmacokinetic study of SHZTN.
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Medicamentos de Ervas Chinesas , Espectrometria de Massas em Tandem , Ratos , Animais , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida , Medicamentos de Ervas Chinesas/farmacocinética , Administração Oral , Reprodutibilidade dos TestesRESUMO
The incidence of nonalcoholic fatty liver disease (NAFLD) is increasing recently and has become one of the most common clinical liver diseases. Since the pathogenesis of NAFLD has not been completely elucidated, few effective therapeutic drugs are available. As the "second genome" of human body, gut microbiota plays an important role in the digestion, absorption and metabolism of food and drugs. Gut microbiota can act as an important driver to advance the occurrence and development of NAFLD, and to accelerate its progression to cirrhosis and hepatocellular carcinoma. Growing evidence has demonstrated that gut microbiota and its metabolites directly affect intestinal morphology and immune response, resulting in the abnormal activation of inflammation and intestinal endotoxemia; gut dysbiosis also causes dysfunction of gut-liver axis via alteration of bile acid metabolism pathway. Because of its composition diversity and disease-specific expression characteristics, gut microbiota holds strong promise as novel biomarkers and therapeutic targets for NAFLD. Intervening intestinal microbiota, such as antibiotic/probiotic treatment and fecal transplantation, has been a novel strategy for preventing and treating NAFLD. In this article, we have reviewed the emerging functions and association of gut bacterial components in different stages of NAFLD progression and discussed its potential implications in NAFLD diagnosis and therapy.
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Microbioma Gastrointestinal , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Humanos , Disbiose/terapia , Disbiose/microbiologia , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/terapia , Hepatopatia Gordurosa não Alcoólica/metabolismoRESUMO
Glove-based wearable sensors can offer the potential ability to a fast and on-site environmental threat assessment, which is crucial for timely and informed incident management. In this study, an on-demand surface-enhanced Raman scattering (SERS) array sensor has been patterned on fire-retardant fibre gloves via the screen-printing technique in large batches. The screen-printed ink contains one-pot synthesized silver nanoparticle and molybdenum disulfide nanocomposite (Ag/MoS2), and polyanionic cellulose (PAC) as a new adhesive agent. Rhodamine 6G (R6G) was employed as an initial probe molecule to systematically evaluate the performance of the resulting sensor. The results suggest that the fabricated fire-retardant screen-printed SERS array sensor displays high reproducibility and stability at 250 °C, with the lower detection limit of 10-13 M for R6G. The spot-to-spot SERS signals show that the intensity variation was less than 10%. Besides, the SERS signals can be maintained over 7 weeks. Further investigation was then successfully carried out to detect polycyclic aromatic hydrocarbons (PAHs), which are commonly used as flammable chemicals. In our perception, this wearable fire-retardant screen-printed SERS array sensor would be an ideal candidate for practical on-site environmental emergency monitoring due to its fire-retardant capability and timely measurement on a portable carrier.
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Retardadores de Chama , Nanopartículas Metálicas , Dispositivos Eletrônicos Vestíveis , Nanopartículas Metálicas/química , Reprodutibilidade dos Testes , Prata/químicaRESUMO
The genus Maytenus is a member of the Celastraceae family, of which several species have long been used in traditional medicine. Between 1976 and 2021, nearly 270 new compounds have been isolated and elucidated from the genus Maytenus. Among these, maytansine and its homologues are extremely rare in nature. Owing to its unique skeleton and remarkable bioactivities, maytansine has attracted many synthetic endeavors in order to construct its core structure. In this paper, the current status of the past 45 years of research on Maytenus, with respect to its chemical and biological activities are discussed. The chemical research includes its structural classification into triterpenoids, sesquiterpenes and alkaloids, along with several chemical synthesis methods of maytansine or maytansine fragments. The biological activity research includes activities, such as anti-tumor, anti-bacterial and anti-inflammatory activities, as well as HIV inhibition, which can provide a theoretical basis for the better development and utilization of the Maytenus.
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Alcaloides/química , Maitansina/análogos & derivados , Maytenus/química , Compostos Fitoquímicos/química , Sesquiterpenos/química , Triterpenos/química , Alcaloides/classificação , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Fármacos Anti-HIV/química , Fármacos Anti-HIV/isolamento & purificação , Fármacos Anti-HIV/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Humanos , Maitansina/isolamento & purificação , Maitansina/farmacologia , Maytenus/metabolismo , Estrutura Molecular , Compostos Fitoquímicos/classificação , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Plantas Medicinais , Sesquiterpenos/classificação , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Relação Estrutura-Atividade , Triterpenos/classificação , Triterpenos/isolamento & purificação , Triterpenos/farmacologiaRESUMO
OBJECTIVE: This study aimed to evaluate the effects of porcine acellular cartilaginous matrix (pACM) on the proliferation and differentiation of human adipose-derived stromal cells (hADSCs). METHODS: pACM was prepared from porcine articular cartilage through decellularization treatment. hADSCs were isolated from human adipose tissues and cultured with different pACM concentrations. No pACM was used as the control group. The effect of pACM on hADSCs proliferation was detected by CCK-8 method. Moreover, the effect of pACM on hADSCs chondrogenic differentiation was analyzed through fluorescence quantitative polymerase chain reaction and Western blot. RESULTS: hADSCs proliferation rate in 0.5, 1.0, and 2.0 mg·mL⻹ pACM groups was not significantly different from that in the control group, whereas that in 4.0 and 8.0 mg·mL⻹ pACM group was lower than that in the control group (P<0.05). The expression levels of pACM chondrogenic genes, including SOX-9, collagen type â ¡ alpha 1 chain (COL2A1), and aggrecan (ACAN) and cell adhesion-related gene LAMININ in 0.5, 1.0, and 2.0 mg·mL⻹ pACM group were higher than those of the control group (P<0.05), but that of a stemness-related gene Notch-1 was lower than that of the control group (P<0.05). No statistical difference was found in the expression of a lipogenesis-related gene peroxisome proliferator-activated receptor-γ (PPAr-γ) (P>0.05). The expression levels of chondrogenic proteins (SOX-9, COL2A1, and ACAN) were higher than those of the control group (P<0.05). CONCLUSIONS: Appropriate pACM con-centrations do not affect hADSCs proliferation but can induce hADSCs chondrogenic differentiation.
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Adipócitos , Células-Tronco , Tecido Adiposo , Animais , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Condrogênese , Humanos , Células Estromais , SuínosRESUMO
Bamboo forests have an efficient carbon sequestration capacity and play an important role in responding to global climate change. However, the current estimation of bamboo carbon storage has some errors, leading to uncertainty in the spatiotemporal pattern of bamboo forest carbon storage. This study simulated aboveground carbon storage of Zhejiang Province, China, during 1984-2014 based on the combination of an improved BIOME-BGC (biogeochemical cycles) model and remote sensing data, with the accuracy being verified with forest resource inventory data. The spatio-temporal distribution and environmental factors of aboveground carbon storage were analyzed. The results showed that the simulated carbon storage was accurate, with average correlation coefficient (r), root mean square error (RMSE) and relative bias (rBIAS) being 0.75, 7.24 Mg C·hm-2 and -2.57 Mg C·hm-2, respectively. Generally, the aboveground carbon storage of bamboo forests in the whole province tended to increase from 1984 to 2014, the range of aboveground carbon density was 13.10-17.14 Mg C·hm-2, and that of the total aboveground carbon storage was between 9.94-17.19 Tg C. The high aboveground carbon storage of bamboo was mainly distributed in developed bamboo industry areas, such as Anji, Lin'an, and Longyou. The change of aboveground carbon storage in bamboo forest was significantly correlated with temperature, precipitation, radiation, CO2 concentration and nitrogen deposition, with higher partial correlation coefficients between precipitation and temperature and carbon storage.
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Sequestro de Carbono , Florestas , Biomassa , Carbono , China , Ecossistema , Monitoramento Ambiental , Sasa , Análise Espaço-Temporal , ÁrvoresRESUMO
Based on the MODIS surface reflectance data, five vegetation indices, including norma-lized difference vegetation index (NDVI), simple ratio index (SR), Gitelson green index (GI), enhanced vegetation index (EVI) and soil adjusted vegetation index (SAVI) were constructed as remote sensing variables, coupled with the seven original spectral reflectance bands of MODIS. Stepwise regression and correlation analysis were used to select the variables, and the stepwise regression and Back Propagation (BP) neural network models were constructed based on the measured LAI to retrieve the LAI time series data of Phyllostachys praecox (Lei bamboo) forest during the period from January 2014 to March 2017. The retrieval results were compared with MOD15A2 LAI products during the same period. The results showed that SR was the single variable selected for the stepwise regression model. The correlations of LAI with bands b1, b2, b3, b7 and five vegetation indices were significant, which could be used as input variables of BP neural network model. There was a significant correlation between the LAI estimated from BP neural network and measured LAI, with the R2 of 0.71, RMSE of 0.34, and RMSEr of 13.6%. R2 was increased by 10.9%, RMSE decreased by 5.6%, and RMSEr decreased by 12.3% compared with LAI estimated from stepwise regression method. R2 was increased by 54.5%, RMSE decreased by 79.3%, and RMSEr decreased by 79.1% compared with MODIS LAI. The LAI of Lei bamboo forest could be accurately retrieved using BP neural network method based on MODIS reflectance time series data, which would be a feasible method for rapid monitoring of LAI in Lei bamboo forest.
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Folhas de Planta , Poaceae/fisiologia , Florestas , Redes Neurais de Computação , Tecnologia de Sensoriamento RemotoRESUMO
The aim of this study was to investigate the effects of cyclophosphamide (CPA) on cashmere shedding in cashmere goats. Thirty-two castrated Liaoning cashmere goats were randomly allotted to four groups, with eight replicates in each group. The four groups were injected intravenously with CPA doses of 0, 15, 20 and 25 mg/kg body weight, respectively. Feed intake, body weight, body temperature, and sphygmus were recorded and the erythrocyte count, leukocyte count, hemoglobin content, and cashmere yield and length were determined. CPA has no significant effect on feed intake, body weight, body temperature, or sphygmus of cashmere goats. It was found that CPA significantly decreased the erythrocyte count and hemoglobin content in cashmere goats on the days immediately following injection, but the effects on erythrocytes diminished within 6 days, with hemoglobin content returning to normal within 10 days. Cashmere fiber began to shed on about day 10 after injection with CPA. CPA had no significant effect on cashmere length but significantly increased cashmere yield. The results indicate that CPA can induce cashmere shedding and achieve the purpose of concentrated defleecing. A dose of 20 mg/kg body weight is preferable for hair removal and regrowth in cashmere goats.
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Ciclofosfamida/administração & dosagem , Ciclofosfamida/farmacologia , Cabras/fisiologia , Remoção de Cabelo/métodos , Cabelo/efeitos dos fármacos , Cabelo/crescimento & desenvolvimento , Muda/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Contagem de Eritrócitos , Cabras/sangue , Hemoglobinas/metabolismo , Injeções Intravenosas , Masculino , Fatores de TempoRESUMO
The extraction adsorbent was fabricated by immobilizing the highly specific recognition and binding of aptamer onto the surface of Fe3 O4 magnetic nanoparticles, which not only acted as recognition elements to recognize and capture the target molecule berberine from the extract of Cortex phellodendri, but also could favor the rapid separation and purification of the bound berberine by using an external magnet. The developed solid-phase extraction method in this work was useful for the selective extraction and determination of berberine in Cortex phellodendri extracts. Various conditions such as the amount of aptamer-functionalized Fe3 O4 magnetic nanoparticles, extraction time, temperature, pH value, Mg2+ concentration, elution time and solvent were optimized for the solid-phase extraction of berberine. Under optimal conditions, the purity of berberine extracted from Cortex phellodendri was as high as 98.7% compared with that of 4.85% in the extract, indicating that aptamer-functionalized Fe3 O4 magnetic nanoparticles-based solid-phase extraction method was very effective for berberine enrichment and separation from a complex herb extract. The applicability and reliability of the developed solid-phase extraction method were demonstrated by separating berberine from nine different concentrations of one Cortex phellodendri extract. The relative recoveries of the spiked solutions of all the samples were between 95.4 and 111.3%, with relative standard deviations ranging between 0.57 and 1.85%.
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Berberina/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Nanopartículas de Magnetita , Phellodendron/química , Reprodutibilidade dos Testes , Extração em Fase SólidaRESUMO
A sensitive and stable bioassay for the detection of Aß oligomer (Aßo), a potentially promising candidate biomarker for Alzheimer's disease (AD) diagnosis, was developed using Fe3O4 magnetic nanoparticles (MNPs) as the recognition and concentration elements and BaYF5:Yb,Er upconversion nanoparticles (UCNPs) as highly sensitive labels, conjugated with the Aßo aptamer (DNA1) and the complementary oligonucleotide of the Aßo aptamer (DNA2), respectively. The DNA1 hybridized with DNA2 to form the duplex structure on the surface of the MNPs/UCNPs nanocomposites probe. When the target Aßo was introduced, the aptamer DNA1 preferentially bound with Aßo and caused the dissociation of some complementary DNA2, liberating some UCNP-labeled complementary DNA2 and leading to a decreased upconversion fluorescent intensity on the surface of MNPs. The decreased fluorescence intensity of UCNPs was related to the concentration of Aßo in the range of 0.2-15nM with a detection limit of 36 pM. The developed method then was successfully applied to measure Aßo in artificial cerebrospinal fluid. Benefiting from the magnetic separation and concentration effect of MNPs, the high sensitivity of UCNPs, as well as the selectivity and stability of the aptamer, the present strategy offered valuable information related to early diagnosis of AD process.
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Peptídeos beta-Amiloides/líquido cefalorraquidiano , Aptâmeros de Nucleotídeos/química , Bário/química , Técnicas Biossensoriais/métodos , Corantes Fluorescentes/química , Elementos da Série dos Lantanídeos/química , Nanopartículas de Magnetita/química , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/diagnóstico , Peptídeos beta-Amiloides/análise , Érbio/química , Humanos , Nanopartículas de Magnetita/ultraestrutura , Nanopartículas/química , Nanopartículas/ultraestrutura , Itérbio/química , Ítrio/químicaRESUMO
This study focused on retrieval of net photosynthetic rate (Pn) of moso bamboo forest based on analysis of wavelet transform on hyperspectral reflectance data of moso bamboo forest leaf. The result showed that the accuracy of Pn retrieved by the ideal high frequency wavelet vegetation index ( VI) was higher than that retrieved by low frequency wavelet VI and spectral VI. Normalized difference vegetation index of wavelet (NDVIw), simple ratio vegetation index of wavelet (SRw) and difference vegetation index of wavelet (Dw) constructed by the first layer of high frequency coefficient through wavelet decomposition had the highest relationship with Pn, with the R² of 0.7 and RMSE of 0.33; low frequency wavelet VI had no advantage compared with spectral VI. Significant correlation existed between Pn estimated by multivariate linear model constructed by the ideal wavelet VI and the measured Pn, with the R² of 0.77 and RMSE of 0.29, and the accuracy was significantly higher than that of using the spectral VI. Compared with the fact that sensitive spectral bands of the retrieval through spectral VI were limited in the range of visible light, the wavelength of sensitive bands of wavelet VI ranged more widely from visible to infrared bands. The results illustrated that spectrum of wavelet transform could reflect the Pn of moso bamboo more in detail, and the overall accuracy was significantly improved than that using the original spectral data, which provided a new alternative method for retrieval of Pn of moso bamboo forest using hyper spectral remotely sensed data.
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Fotossíntese , Folhas de Planta/fisiologia , Poaceae/fisiologia , Análise de Ondaletas , Florestas , Luz , Modelos Lineares , Tecnologia de Sensoriamento Remoto , Análise EspectralRESUMO
LAI is one of the most important observation data in the research of carbon cycle of forest ecosystem, and it is also an important parameter to drive process-based ecosystem model. The Moso bamboo forest (MBF) and Lei bamboo forest (LBF) were selected as the study targets. Firstly, the MODIS LAI time series data during 2014-2015 was assimilated with Dual Ensemble Kalman Filter method. Secondly, the high quality assimilated MBF LAI and LBF LAI were used as input dataset to drive BEPS model for simulating the gross primary productivity (GPP), net ecosystem exchange (NEE) and total ecosystem respiration (TER) of the two types of bamboo forest ecosystem, respectively. The modeled carbon fluxes were evaluated by the observed carbon fluxes data, and the effects of different quality LAI inputs on carbon cycle simulation were also studied. The LAI assimilated using Dual Ensemble Kalman Filter of MBF and LBF were significantly correlated with the observed LAI, with high R2 of 0.81 and 0.91 respectively, and lower RMSE and absolute bias, which represented the great improvement of the accuracy of MODIS LAI products. With the driving of assimilated LAI, the modeled GPP, NEE, and TER were also highly correlated with the flux observation data, with the R2 of 0.66, 0.47, and 0.64 for MBF, respectively, and 0.66, 0.45, and 0.73 for LBF, respectively. The accuracy of carbon fluxes modeled with assimilated LAI was higher than that acquired by the locally adjusted cubic-spline capping method, in which, the accuracy of mo-deled NEE for MBF and LBF increased by 11.2% and 11.8% at the most degrees, respectively.
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Ciclo do Carbono , Florestas , Poaceae , Carbono , ÁrvoresRESUMO
Mild traumatic brain injury (MTBI) is defined as a mild brain trauma resulting in a short loss of consciousness and alteration of mental status. It may also occasionally develop persistent and progressive symptoms. It has been confirmed that MTBI causes changes of anatomic structures in central nervous system and biomarkers in the body fluid. However, there is no sufficient research on relevance among threshold for the brain injury, individual vulnerability and duration of disturbance of consciousness. Furthermore, there are no reliable diagnostic methods to establish whether a blow to the head is sufficient to cause the brain injury. This review provides references for biomarkers in cerebrospinal fluid and blood associated with TBI. It also provides application status and potential prospects for further assessment and diagnosis of MTBI.
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Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Lesões Encefálicas/sangue , Lesões Encefálicas/líquido cefalorraquidiano , Concussão Encefálica/complicações , Lesões Encefálicas/diagnóstico , Lesões Encefálicas/etiologia , Progressão da Doença , HumanosRESUMO
AIM: To synthesize three novel esterified-derivatives of mangiferin and evaluate their hypoglycemic activities. METHODS: Acetic, propionic, and butyric anhydride were reacted with mangiferin, respectively. The hypoglycemic activity of the derivatives was evaluated using a hyperglycemic mouse model induced by streptozotocin (STZ), and the islet cells were checked by biopsy inspection. RESULTS: 7, 2', 3', 4', 6'-penta-acetyl-mangiferin (PAM), 3, 6, 7, 2', 3', 4', 6'-hepta-propionyl-mangiferin (HPM) and 3, 6, 7, 2', 3', 4'-hexa-butyryl-mangiferin (HBM) were synthesized and their structures were identified by MS,(1)H, (13)C NMR, and 2D NMR. These three compounds were reported for the first time. PAM group (0.5, 0.25 mmol·kg(-1)), HPM group (0.5, 0.25 mmol·kg(-1)), and HBM group (0.5, 0.25, 0.125 mmol·kg(-1)) mice showed strong hypoglycemic activity (P < 0.01); mangiferin group (1, 0.5 mmol·kg(-1)), PAM group (0.125 mmol·kg(-1)) and HPM group (0.125 mmol·kg(-1)) showed marginal hypoglycemic activity (P < 0.05); mangiferin group (0.25 mmol·kg(-1)) had the potential for a hypoglycemic effect, although it did not demonstrate that statistically. In histological examination, the islet cells of the PAM, HPM, and HBM groups could recover from the STZ damage; islet cells of the mangiferin group could recover also, but less than the esterified-derivative groups. CONCLUSION: Derivatives could repair the damaged islet cells, and had higher lipid-solubility and stronger hypoglycemic activity than mangiferin itself. There existed a structure activity effect, and a solubility effect relationship: the larger esterification moieties, or the higher lipid-solubility, the stronger the hypoglycemic activity (no ester â acetyl â propionyl â butyryl). Esterified derivatives of mangiferin are potential compounds for new anti-diabetes drugs.