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1.
Front Chem ; 12: 1375552, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38591057

RESUMO

Thermally activated delayed fluorescence (TADF) materials with high photoluminescence quantum yields and fast reverse intersystem crossing (RISC) capabilities are highly desirable for applications in high-efficiency organic light-emitting diodes. Herein, we report the synthesis as well as structural and photophysical properties of 5,9-diselena-13b-boranaphtho[3,2,1-de]anthracene (SeBSe) as a narrowband-emissive TADF material. The incorporation of two selenium atoms into the boron-fused pentacyclic π-core results in a small singlet-triplet energy gap (ΔE ST) and thereby significant TADF properties. Moreover, theoretical calculations revealed a noticeable spin-orbit coupling enhancement between the singlet and triplet manifolds in SeBSe by virtue of the heavy-atom effect of selenium atoms. Consequently, SeBSe allows ultrafast spin-flip RISC with the rate constant surpassing 108 s-1, which far exceeds the corresponding fluorescence radiative decay rate (∼106 s-1), enabling an ideal singlet-triplet superimposed excited state.

2.
Curr Issues Mol Biol ; 46(3): 1921-1923, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38534741

RESUMO

As a physiological defense mechanism, inflammation is a complex response to harmful stimuli [...].

3.
Opt Lett ; 49(4): 818-821, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38359190

RESUMO

Artificial neural networks usually consist of successive linear multiply-accumulate operations and nonlinear activation functions. However, most optical neural networks only achieve the linear operation in the optical domain, while the optical implementation of activation function remains challenging. Here we present an optical ReLU-like activation function (with 180° rotation) based on a semiconductor laser subject to the optical injection in an experiment. The ReLU-like function is achieved in a broad regime above the Hopf bifurcation of the injection-locking diagram and is operated in the continuous-wave mode. In particular, the slope of the activation function is reconfigurable by tuning the frequency difference between the master laser and the slave laser.

4.
J Colloid Interface Sci ; 657: 193-207, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38039880

RESUMO

Recently, microwave absorption (MA) materials have attracted intensive research attention for their ability to counteract the effects of ever-growing electromagnetic pollution. However, conventional microwave absorbers suffer from complex fabrication processes, poor stability and different optimal thicknesses for minimum reflection loss (RLmin) and widest effective absorption bandwidth (EAB). To address these issues, we have used electrospinning followed by high-temperature annealing in argon to develop a flexible microwave absorber with strong wideband absorption. The MA properties of the carbon nanofibers (CNFs) can be tuned by adjusting annealing temperature, and are dependent on the composition and microstructure of the CNFs. The absorber membrane obtained at 800 °C consists of Fe0.64Ni0.36@graphite core-shell nanoparticles (NPs) embedded in CNFs, formed via a corrosion-like transformation from NiFe2O4 to Fe0.64Ni0.36 followed by surface graphitization. This nanostructure greatly enhances magnetic-dielectric synergistic loss to achieve superior MA properties, with an RLmin of -57.7 dB and an EAB of 6.48 GHz (11.20-17.68 GHz) both acquired at a thickness of 2.1 mm. This work provides useful insights into structure-property relationship of the CNFs, sheds light on the formation mechanism of Fe0.64Ni0.36@graphite NPs, and offers a simple synthesis route to fabricate light-weight and flexible microwave absorbers.

5.
Life Sci ; 334: 122176, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37858718

RESUMO

AIMS: Intestinal ischemia reperfusion (II/R) is a common clinical emergency. Ferroptosis is reported to play a role in II/R injury. Our previous studies revealed that corilagin significantly attenuates intestinal ischemia/reperfusion injuries. However, the underlying molecular mechanism is unclear and requires further study. MATERIALS AND METHODS: DAO, GSSG/T-GSH, MDA, and Fe2+ were measured by assay kits, 4-HNE was assessed by IHC, and 15-LOX was measured by ELISA. Mitochondrial damage was observed by TEM and cellular oxidation levels were detected by C11-BODIPY 581/591 and DHE probes. LC3, p62, Beclin1, ACSL4, GPX4, NCOA4, and ferritin expression were examined by WB in vivo and in vitro. IF, co-IF, q-PCR, and constructed NCOA4-knock-down IEC-6 cells were used to evaluate the role of NCOA4 in the effect of corilagin against II/R injury. Temporal and nucleoplasmic variations with or without corilagin were observed by WB. Co-IP and molecular docking were used to investigate the NCOA4-ferritin interaction. KEY FINDINGS: Corilagin attenuated II/R-induced ferroptosis both in vitro and in vivo. Further study revealed that the anti-ferroptosis bioactivity of corilagin might be due to the modulation of iron homeostasis via inhibition of ferritinophagy in an NCOA4-dependent manner. SIGNIFICANCE: Corilagin might be a potential therapeutic agent for II/R-induced tissue injury.


Assuntos
Ferroptose , Isquemia Mesentérica , Traumatismo por Reperfusão , Animais , Camundongos , Simulação de Acoplamento Molecular , Traumatismo por Reperfusão/tratamento farmacológico , Ferritinas , Isquemia
6.
Curr Issues Mol Biol ; 45(7): 5824-5829, 2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37504284

RESUMO

Inflammation is one of the body's most complex physiological defense mechanisms against harmful substances [...].

7.
Mol Nutr Food Res ; 67(13): e2200773, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37118920

RESUMO

SCOPE: Intestinal ischemia-reperfusion (II/R) injury is a common pathological process with high morbidity and mortality. Effective prevention and treatment therapies for II/R are clinically necessary. 6-Shogaol (6-SG), the main active ingredient in dried ginger, behaviors multiple biological activities, including anti-inflammation, antioxidation, and anti-apoptosis. This study aims to elucidate the protective effects and mechanism of 6-SG against II/R-induced injury. METHODS AND RESULTS: Sprague-Dawley rats are pre-treated orally with 6-SG and subjected to II/R injury by clamping superior mesenteric artery for 1 h and reperfusion for 2 h. Caco-2 cells are challenged by hypoxia/reoxygenation to mimic II/R in vitro. 6-SG pre-treatment protects against II/R injury by reducing intestinal morphological damage and intestinal barrier injury via inhibiting cell apoptosis. Network pharmacology and molecular docking analyses reveal that 6-SG has a high affinity with brain-derived neurotrophic factor (BDNF) formed homodimer or heterodimer with NT4 instead of the monomer, and thus the dimer configuration is stabilized, activating BDNF/TrkB/PI3K/AKT signaling pathway and inhibiting II/R-induced cell apoptosis. The outcome is further validated both in vivo and in vitro. CONCLUSION: 6-Shogaol protects against II/R injury by inhibiting cell apoptosis through the BDNF/TrkB/PI3K/AKT pathway. This study offers a new understanding of the protection mechanism of 6-SG against II/R-induced injury.


Assuntos
Enteropatias , Traumatismo por Reperfusão , Zingiber officinale , Humanos , Ratos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Ratos Sprague-Dawley , Células CACO-2 , Simulação de Acoplamento Molecular , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/prevenção & controle , Reperfusão , Isquemia
8.
Genomics ; 114(5): 110477, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36058475

RESUMO

Fish exhibit different muscle structures and growth characteristics compared with mammals. We used a spatial transcriptomics approach and examined myotomal muscle sections from zebrafish. Adult muscles were divided into eight regions according to spatial gene expression characteristics. Slow muscle was located in the wedge-shaped region near the lateral line and at the base of the dorsal fin, intermediate muscle was located in a ribbon-shaped region adjacent to slow muscle, and fast muscle was located in the deep region of the trunk, surrounded by intermediate muscle; the interior of fast muscle was further divided into 6 parts by their transcriptomic features. Combined analysis of adult and larval data revealed that adult muscles contain specific regions similar to larval muscles. These regions showed active myogenesis and a high expression of genes associated with muscle hyperplasia. This is the first study to apply spatial transcriptomics to fish myotomal muscle structure and growth.


Assuntos
Transcriptoma , Peixe-Zebra , Animais , Larva , Mamíferos , Desenvolvimento Muscular/genética , Músculos , Peixe-Zebra/genética
9.
Front Neurosci ; 16: 956854, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992903

RESUMO

Background: Post-stroke hemiparesis strongly affects stroke patients' activities of daily living and health-related quality of life. Scalp acupuncture (SA) is reportedly beneficial for post-stroke hemiparesis. However, there is still no standard of SA for the treatment of post-stroke hemiparesis. Apriori algorithm-based association rule analysis is a kind of "if-then" rule-based machine learning method suitable for investigating the underlying rules of acupuncture point/location selections. This study aimed to investigate the core SA combinations for the treatment of post-stroke hemiparesis by using a systematic review and Apriori algorithm-based association rule analysis. Methods: We conducted a systematic review to include relevant randomized controlled trial (RCT) studies investigating the effects of SA treatment in treating patients with post-stroke hemiparesis, assessed by the Fugl-Meyer Assessment (FMA) score. We excluded studies using herbal medicine or manual acupuncture. Results: We extracted 33 SA locations from the 35 included RCT studies. The following SA styles were noted: International Standard Scalp Acupuncture (ISSA), WHO Standard Acupuncture Point Locations (SAPL), Zhu's style SA, Jiao's style SA, and Lin's style SA. Sixty-one association rules were investigated based on the integrated SA location data. Conclusions: SAPL_GV20 (Baihui), SAPL_GV24 (Shenting), ISSA_MS6_i (ISSA Anterior Oblique Line of Vertex-Temporal, lesion-ipsilateral), ISSA_MS7_i (ISSA Posterior Oblique Line of Vertex-Temporal, lesion-ipsilateral), ISSA_PR (ISSA Parietal region, comprised of ISSA_MS5, ISSA_MS6, ISSA_MS7, ISSA_MS8, and ISSA_MS9), and SAPL_Ex.HN3 (Yintang) can be considered the core SA location combination for the treatment of post-stroke hemiparesis. We recommend a core SA combination for further animal studies, clinical trials, and treatment strategies.

10.
Chemistry ; 28(48): e202202289, 2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-35946986

RESUMO

Invited for the cover of this issue is the group of H. Sasabe and J. Kido at Yamagata University in Japan. The image depicts the molecular structures of N-B-O embedded multi-resonant thermally activated delayed fluorescent (MR-TADF) emitters, which achieved ultra-pure deep-blue/green emission with high efficiency in OLEDs. Read the full text of the article at 10.1002/chem.202201605.

11.
Front Immunol ; 13: 916102, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35812413

RESUMO

Background: Lipopolysaccharide (LPS)-induced acute lung injury (ALI) induces endoplasmic reticulum stress, unfolded protein response (UPR), apoptosis, and inflammation. Inositol-requiring enzyme 1 (IRE1)-α is important for adaptive and apoptotic UPR determination during ER stress. The aqueous extract of Descuraniae Semen (AEDS) is reported to be a safe and effective herb for the treatment of pulmonary edema as it shows anti-inflammatory activities. Methods: We investigated the effects of AEDS on LPS-induced ALI in A549 cells with respect to the regulation of IRE1α-dependent UPR, proteasomal degradation, mitochondrial membrane potential (MtMP), inflammation, and apoptosis. Results: AEDS attenuated ER stress by regulating the proteasomal degradation. LPS induced ER stress [binding immunoglobulin protein (BiP), phosphorylated IRE1α, sliced X-box binding protein 1 [XBP1s], phosphorylated cJUN NH2-terminal kinase (pJNK), B-cell lymphoma (Bcl)-2-associated X (Bax), Bcl-2], inflammation (nucleus factor-kappa B (NF-κB) p65 nuclear translocation, nucleus NF-κB, pro-inflammatory cytokines] and apoptosis [C/EBP homologous protein (CHOP), cytochrome c, caspase-8, and caspase-6, and TUNEL] were significantly attenuated by AEDS treatment in A549 cells. AEDS prevents LPS-induced decreased expression of MtMP in A549 cells. Conclusions: AEDS attenuated LPS-induced inflammation and apoptosis by regulating proteasomal degradation, promoting IRE1α-dependent adaptive UPR, and inhibiting IRE1α-dependent apoptotic UPR. Moreover, IRE1α-dependent UPR plays a pivotal role in the mechanisms of LPS-induced ALI. Based on these findings, AEDS is suggested as a potential therapeutic option for treating patients with ALI.


Assuntos
Lesão Pulmonar Aguda , Lipopolissacarídeos , Células A549 , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/tratamento farmacológico , Apoptose , Endorribonucleases/metabolismo , Humanos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Lipopolissacarídeos/farmacologia , NF-kappa B/metabolismo , Proteínas Serina-Treonina Quinases , Sêmen/metabolismo , Resposta a Proteínas não Dobradas
12.
Chemistry ; 28(48): e202201605, 2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-35678220

RESUMO

In this study, we synthesized and characterized multiresonant thermally activated delayed fluorescent (TADF) materials embedded with nitrogen-boron-oxygen (N-B-O), exhibiting color-tunability between blue and green, namely NBO, m-DiNBO, and p-DiNBO. The three emitter materials showed a high photoluminescence quantum yield (PLQY) and a state-of-the-art narrow full width at half maximum (FWHM) of 96 %/25 nm, 87 %/17 nm, and 99 %/19 nm, respectively. For m-DiNBO and p-DiNBO, the emission color could be tuned from blue to green by regulating the nonbonding/bonding molecular orbital characters. Owing to the expanded planar molecular structure, m-DiNBO and p-DiNBO showed high horizontal dipole ratio (Θ) of 88 % and 92 %, respectively. OLEDs were prepared with NBO, m-DiNBO, and p-DiNBO, exhibiting high external quantum efficiencies of 16.8 %, 24.2 %, and 21.6 %, respectively. NBO and m-DiNBO exhibited pure-blue emission with CIE coordinates of (0.137, 0.142) and (0.126, 0.098), respectively. p-DiNBO showed pure-green emission with a CIE coordinate of (0.258, 0.665).


Assuntos
Boro , Nitrogênio , Oxigênio
13.
RSC Adv ; 12(25): 16153-16164, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35733656

RESUMO

Microvia filling by copper electroplating was performed using plating solution with 1-(4-hydroxyphenyl)-2H-tetrazole-5-thione (HPTT) as the leveler. Galvanostatic Measurements (GMs), Linear Sweep Voltammetry (LSV) and Electrochemical Impedance Spectroscopy (EIS) tests were carried out to investigate the electrochemical behaviors of HPTT and its synergistic effect with other additives, in comparison with 1-phenyltetrazole-5-thione (PMT). GMs showed a convection-dependent interaction between PEP and HPTT. LSV and EIS tests indicated both HPTT and PMT enhanced the inhibition effect of PEP, and the synergistic effect of HPTT and PEP was stronger than that of PMT. Cross-section images illustrated the filling rate of the microvia with a 150 µm diameter and a 75 µm depth was 95.6% in 60 minutes with HPTT as the leveler. Frontier Molecular Orbitals (FMO) and Electrostatic Potential (ESP) of HPTT and PMT using quantum chemical calculations predicted the reaction sites for electrophilic and nucleophilic attack. Quantum chemical calculations suggested that HPTT is easier than PMT to bond to a copper surface and PEP.

14.
Molecules ; 27(9)2022 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-35566346

RESUMO

Psoriasis is reported to be a common chronic immune-mediated skin disease characterized by abnormal keratinocytes and cell proliferation. Perilla leaves are rich in essential oils, fatty acids, and flavonoids, which are recognized for their antioxidant and anti-inflammatory effects. In this study, the alleviating effect of essential oil (PO) extracted from Perilla frutescens stems and leaves on imiquimod (IMQ) -induced psoriasis-like lesions in BALB/c mice were investigated. Results showed that PO ameliorated psoriasis-like lesions in vivo, reduced the expression of lymphocyte antigen 6 complex locus G6D (Ly-6G), which is a marker of neutrophil activation, and inhibited the expression of inflammatory factors interleukin 1 (IL-1), interleukin 6 (IL-6), inducible nitric oxide synthase (iNOS), and cyclooxygenase 2 (COX2). In addition, PO significantly decreased the expression of cytokines such as IL-6, IL-1, interleukin 23 (IL-23), interleukin 17 (IL-17), and nuclear factor kappa-B (NF-κB). Furthermore, the down-regulation of mRNA levels of psoriasis-related pro-inflammatory cytokines, such as IL-17, interleukin 22 (IL-22), IL-23, interferon-α (IFN-α), and Interferon-γ (IFN-γ) was observed with the treatment of PO. All results show a concentration dependence of PO, with low concentrations showing the best results. These results suggest that PO effectively alleviated psoriasis-like skin lesions and down-regulated inflammatory responses, which indicates that PO could potentially be used for further studies on inflammation-related skin diseases such as psoriasis and for the treatment of psoriasis such as psoriasis natural plant essential oil resources.


Assuntos
Dermatite , Óleos Voláteis , Perilla frutescens , Psoríase , Animais , Citocinas/metabolismo , Dermatite/patologia , Modelos Animais de Doenças , Imiquimode/efeitos adversos , Interleucina-1 , Interleucina-17 , Interleucina-23 , Interleucina-6/farmacologia , Queratinócitos , Camundongos , Camundongos Endogâmicos BALB C , Óleos Voláteis/efeitos adversos , Perilla frutescens/metabolismo , Psoríase/induzido quimicamente , Psoríase/tratamento farmacológico , Pele/metabolismo
15.
Open Biol ; 12(5): 210317, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35506205

RESUMO

Exosomes, a subset of small extracellular vesicles, carry various nucleic acids, proteins, lipids, amino acids and metabolites. They function as a mode of intercellular communication and molecular transfer. Exosome cargo molecules, including small non-coding RNAs (sncRNAs), are involved in the immune response in various organisms. However, the role of exosome-derived sncRNAs in immune responses in molluscs remains unclear. Here, we aimed to reveal the sncRNAs involved in the immune response during grafting transplantation by the pearl oyster Pinctada fucata. Exosomes were successfully extracted from the P. fucata haemolymph during graft transplantation. Abundant microRNAs (miRNAs) and PIWI-interacting RNAs (piRNAs) were simultaneously discovered in P. fucata exosomes by small RNA sequencing. The expression patterns of the miRNAs and piRNAs at the grafting and initial stages were not substantially different, but varied significantly between the initial and later stages. Target prediction and functional analysis indicate that these miRNAs and piRNAs are related to immune response upon grafting transplantation, whereas piRNAs may also be associated with transposon silencing by targeting with genome transposon elements. This work provides the basis for a functional understanding of exosome-derived sncRNAs and helps to gain further insight into the PIWI/piRNA pathway function outside of germline cells in molluscs.


Assuntos
Exossomos , MicroRNAs , Pinctada , Pequeno RNA não Traduzido , Animais , Exossomos/genética , Exossomos/metabolismo , Imunidade , MicroRNAs/genética , Pinctada/genética , Pinctada/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo
16.
Front Neurosci ; 16: 851333, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35368268

RESUMO

Background: Stroke leads to tremendous impacts on patients and the healthcare system. It is crucial to explore the potential management of rehabilitation. Acupuncture and traditional Chinese herbal medicine (TCHM) integrated with conventional rehabilitation benefit post-stroke functional recovery. Methods: We retrospectively reviewed the medical records of all patients included in the Integrated Traditional Chinese-Western Medicine care program for stroke (ITCWM-stroke care program) in 2019 in Taipei Tzu Chi Hospital to investigate the effects of acupuncture and TCHM integrated with conventional rehabilitation on National Institutes of Health Stroke Scale (NIHSS) and Barthel Index (BI) scores before and after the program. Results: A total of 255 stroke inpatients were retrieved and divided into acupuncture and acupuncture + TCHM group by hemorrhagic and ischemic stroke types, respectively. All the patients were recruited in the program at the early subacute phase after stroke onset. Of the hemorrhagic and ischemic stroke subjects, the NIHSS and BI total scores were significantly improved in the acupuncture and acupuncture + TCHM groups. The subgroup analysis results showed that in subjects with a baseline BI score ≤ 40, the acupuncture + TCHM group significantly improved BI total score better than the acupuncture group in both hemorrhagic (p < 0.05) and ischemic (p < 0.05) stroke subjects. Conclusion: Acupuncture and TCHM integrated with conventional rehabilitation significantly improve stroke patients' functional recovery at the early subacute phase. Acupuncture + TCHM contributes to better activities of daily living (ADL) improvements in stroke patients with a baseline BI score ≤ 40. We suggest integrating acupuncture and TCHM into the post-stroke rehabilitation strategy, especially for stroke patients with poor ADL function.

17.
EMBO J ; 41(9): e109352, 2022 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-35318705

RESUMO

Neural circuit function requires mechanisms for controlling neurotransmitter release and the activity of neuronal networks, including modulation by synaptic contacts, synaptic plasticity, and homeostatic scaling. However, how neurons intrinsically monitor and feedback control presynaptic neurotransmitter release and synaptic vesicle (SV) recycling to restrict neuronal network activity remains poorly understood at the molecular level. Here, we investigated the reciprocal interplay between neuronal endosomes, organelles of central importance for the function of synapses, and synaptic activity. We show that elevated neuronal activity represses the synthesis of endosomal lipid phosphatidylinositol 3-phosphate [PI(3)P] by the lipid kinase VPS34. Neuronal activity in turn is regulated by endosomal PI(3)P, the depletion of which reduces neurotransmission as a consequence of perturbed SV endocytosis. We find that this mechanism involves Calpain 2-mediated hyperactivation of Cdk5 downstream of receptor- and activity-dependent calcium influx. Our results unravel an unexpected function for PI(3)P-containing neuronal endosomes in the control of presynaptic vesicle cycling and neurotransmission, which may explain the involvement of the PI(3)P-producing VPS34 kinase in neurological disease and neurodegeneration.


Assuntos
Transmissão Sináptica , Vesículas Sinápticas , Endocitose/fisiologia , Endossomos , Neurotransmissores , Fosfatos de Fosfatidilinositol , Sinapses/fisiologia , Transmissão Sináptica/fisiologia
18.
Photochem Photobiol ; 98(1): 262-271, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34342370

RESUMO

Lycium barbarum have received an increasing popularity due to its powerful biological activity and medicinal use. However, the effect of Lycium barbarum on skin remains largely uncharacterized. The general purpose of this paper was to characterize the phenolic compounds in Lycium barbarum extract (LBE) using LC-HRMS/QTOF method and to investigate whether topical administration of LBE can repair skin barrier dysfunction in mice. Our data demonstrated that LBE could not only decrease ROS level and matrix metalloproteinase expression, but also strengthen intrinsic antioxidant defense system including SOD, GSH-Px and CAT, thereby resulting in increased skin collagen content and an improvement of UV-induced skin erythema, thickness and wrinkles. Improved skin barrier functions were highly correlated with increased expression of filaggrin, involucrin and loricrin as well as antioxidant proteins such as Nrf2 and HO-1 in UV-irradiated mice, suggesting that LBE may be promising natural products at a lower cost for the topical application in the treatment of skin diseases with defective barrier function.


Assuntos
Lycium , Animais , Antioxidantes/farmacologia , Lycium/metabolismo , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Fenóis/farmacologia , Extratos Vegetais/farmacologia
19.
Environ Sci Pollut Res Int ; 29(14): 20571-20592, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34741266

RESUMO

The geographical distribution of plant resources is of great significance for studying the origin, distribution, and evolution of species. Climate and geographical factors help shape the distribution of plant species. Dendrobium is a commonly used traditional medicine and a precious economic crop in China. Owing to the over-exploitation and increasing medicinal demand of Dendrobium species plants, systematic investigation of the geographical distribution of the plants and analysis of their potential distribution under climate change are important for protecting Dendrobium plants. We adopted DIVA-GIS to analyze the georeferenced records of 76 species of the Dendrobium species collected from 2166 herbarium records. We analyzed the eco-geographical distribution and species richness of the genus Dendrobium to simulate the distribution of current and future scenarios using MaxEnt. The results revealed the distribution of Dendrobium in 30 provinces of China, with species abundance in Yunnan, Guangxi, Guangdong, and Hainan. Our model identified the following bioclimatic variables: precipitation in the driest months and the warmest seasons, isothermality, and range of annual temperature. Among them, annual precipitation is the most crucial bioclimatic variable affecting the distribution of 16 selected Dendrobium species. The change of climate in the future will lead to an increase in habitat suitability for some Dendrobium species as follows: D. officinal 2.12%, D. hancockii by 6.00%, D. hercoglossum by 8.25%, D. devonianum by 7.71%, D. henryi by 9.40%, and D. hainanense by 13.70%. By contrast, habitat suitability will dramatically decrease for other Dendrobium species: D. chrysotoxum by 0.89%, D. chrysanthum by 12.68%, D. fimbriatum by 5.07%, D. aduncum by 11.44%, D. densiflorum by 18.47%, D. aphyllum by 8.05%, D. loddigesii by 16.45%, D. nobile by 5.41%, D. falconeri by 8.73%, and D. moniliforme by 10.61%. The reduction of these species will be detrimental to the medicinal and economic value of the genus Dendrobium. Therefore, targeted development and reasonable management strategies should be adopted to conserve these valuable resources.


Assuntos
Mudança Climática , Dendrobium , China , Ecossistema , Temperatura
20.
Cellulose (Lond) ; 28(10): 6147-6158, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34025049

RESUMO

Cellulose nanocrystals (CNCs) have attracted tremendous attention because of their excellent chemical and physical properties and due to their renewability and sustainability. This material can be extracted from agricultural by-products such as rice straw, banana tree, or bagasse. Rice straw was selected as the raw material in this study. Initially, a large amount of lignin must be removed by an alkaline process to obtain a slurry. Thereafter, a green bleaching process can be used to remove the remaining lignin in the slurry. An UV-emitting diode with 365 nm wavelength assisted the oxidation reaction of the H2O2 solution without the use of chlorine-containing chemical bleach. The reaction required only 2.5 h to obtain high-purity cellulose and successfully enhanced the yield. Transmission electron microscopy images showed that the CNCs from rice straw were ~ 100 nm long and 10-15 nm wide. The crystalline index and degradation temperature of CNCs were 83.8% and 257 °C, respectively.

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