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1.
Plant Physiol ; 196(2): 1475-1488, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38833579

RESUMO

The asymmetrical distribution of auxin supports high intensity blue light (HBL)-mediated phototropism. Flavonoids, secondary metabolites induced by blue light and TRANSPARENT TESTA GLABRA1 (TTG1), alter auxin transport. However, the role of TTG1 in HBL-induced phototropism in Arabidopsis (Arabidopsis thaliana) remains unclear. We found that TTG1 regulates HBL-mediated phototropism. HBL-induced degradation of CRYPTOCHROME 1 (CRY1) was repressed in ttg1-1, and depletion of CRY1 rescued the phototropic defects of the ttg1-1 mutant. Moreover, overexpression of CRY1 in a cry1 mutant background led to phototropic defects in response to HBL. These results indicated that CRY1 is involved in the regulation of TTG1-mediated phototropism in response to HBL. Further investigation showed that TTG1 physically interacts with CRY1 via its N-terminus and that the added TTG1 promotes the dimerization of CRY1. The interaction between TTG1 and CRY1 may promote HBL-mediated degradation of CRY1. TTG1 also physically interacted with blue light inhibitor of cryptochrome 1 (BIC1) and Light-Response Bric-a-Brack/Tramtrack/Broad 2 (LRB2), and these interactions either inhibited or promoted their interaction with CRY1. Exogenous gibberellins (GA) and auxins, two key plant hormones that crosstalk with CRY1, may confer the recovery of phototropic defects in the ttg1-1 mutant and CRY1-overexpressing plants. Our results revealed that TTG1 participates in the regulation of HBL-induced phototropism by modulating CRY1 levels, which are coordinated with GA or IAA signaling.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Criptocromos , Luz , Fototropismo , Criptocromos/metabolismo , Criptocromos/genética , Arabidopsis/genética , Arabidopsis/fisiologia , Arabidopsis/metabolismo , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Fototropismo/fisiologia , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Mutação/genética , Plantas Geneticamente Modificadas , Luz Azul
2.
Opt Express ; 32(2): 2015-2028, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38297740

RESUMO

Quantum communication satellites have potential for applications in future quantum networks. Photonics integrated chips, due to their compact and lightweight nature, are well-suited for satellite deployment. However, the harsh radiation environment of space can cause permanent damage to these chips, resulting in degraded performance or complete loss of functionality. In this work, we conducted a series of radiation experiments to evaluate the effects of γ rays and high energy protons on quantum key distribution transmitter chips. The results suggest that the insertion loss of the chip is slightly reduced by about 1.5 dB after 100 krad (Si) γ ray irradiation, and further reduced by about 0.5 to 1 dB after 2.39 × 1011/cm2 proton radiation. The half-wave voltages, extinction ratios, and polarization angles are not changed significantly within the measurement error range. Our work proves the feasibility of deploying quantum constellations utilizing terminals based on photonics chips.

3.
Bioorg Chem ; 153: 107900, 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39442460

RESUMO

The discovery and utilization of new fluorescent chromophore is indispensable to exploit high performance probes for biological research. Stokes shift is one of the most important properties of chromophore accounting for super-resolution fluorescence imaging. Intramolecular charge transfer (ICT) is one of the fundamental mechanisms for fluorescence that accompanied by large Stokes shifts. Based on the conformational changes between ground and excited states, ICT models can be divided into two types: conformation-steady ICT, whose conformation remains unchanged, and conformation-changeable ICT, which is characterized by the rotation of the chromophore around an axis upon excitation. Herein, we report a new chromophore whose donor and acceptor parts took a butterfly geometry with a dihedral angle of 21° in ground state and a planar conformation upon photo excitation. The bent conformation might be ascribed to the extra conjugated double bond, which made the coplanarity of the chromophore in ground state get worse. The chromophore shows a remarkable Stokes shift over 150 nm and a high fluorescence quantum yieldof 0.62. The limit of detection is 41 nM, which enabled the imaging of basal as well as induced OCl- in different cells. Moreover, the pronounced spectroscopic properties ensure the in vivo monitoring of OCl- in arthritic mice. This finding would shed light on the exploitation of small molecule probes based on new fluorescence chromophore for precise biological imaging.

4.
J Asian Nat Prod Res ; 26(4): 399-414, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38151899

RESUMO

The new natural products reported in 2022 in peer-reviewed articles in journals with good reputations were reviewed and analyzed. The advances made by Asian research groups in the field of natural products chemistry in 2022 were summarized. Compounds with unique structural features and/or promising bioactivities originating from Asian natural sources were discussed based on their structural classification.


Assuntos
Produtos Biológicos , Produtos Biológicos/química , Estrutura Molecular , Inquéritos e Questionários
5.
J Asian Nat Prod Res ; : 1-16, 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39450496

RESUMO

The new natural products reported in 2023 in peer-reviewed articles in journals with good reputations were reviewed and analyzed. The advances made by Asian research groups in the field of natural products chemistry in 2023 were summarized. Compounds with unique structural features and/or promising bioactivities originating from Asian natural sources were discussed based on their structural classification.

6.
J Asian Nat Prod Res ; 26(7): 780-787, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38560992

RESUMO

Two new iridoid glycosides, piasezkiiosides A (1) and B (2), were isolated from aqueous extract of the whole plant of Rehmannia piasezkii. Their structures were established from the spectroscopic data, chemical transformation, and X-ray diffraction analysis. Compound 1 exhibited weak hepatoprotective activity against APAP-induced HepG2 cell damage.


Assuntos
Glicosídeos Iridoides , Rehmannia , Glicosídeos Iridoides/farmacologia , Glicosídeos Iridoides/química , Glicosídeos Iridoides/isolamento & purificação , Humanos , Células Hep G2 , Estrutura Molecular , Rehmannia/química , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação
7.
J Asian Nat Prod Res ; 26(3): 293-301, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37162445

RESUMO

Four new iridoid glycosides (1-4), rehmaglutosides L-O, were isolated from the air-dried roots of Rehmannia glutinosa. Their structures were established from the spectroscopic data obtained and by chemical evidence. The known mellittoside (5) and ajugol (6) were also obtained in the current investigation, and the structure of mellittoside was unequivocally defined using X-ray diffraction data. Compounds 1-6 were tested for their cytotoxicity against five human tumor cell lines and proliferation effects on Lactobacillus Reuteri.


Assuntos
Glicosídeos , Rehmannia , Humanos , Glicosídeos/farmacologia , Glicosídeos/química , Rehmannia/química , Glicosídeos Iridoides/farmacologia
8.
J Asian Nat Prod Res ; 26(2): 280-292, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36877100

RESUMO

Seven new pentasaccharides (1-7), rehmaglupentasaccharides A-G, were isolated from the air-dried roots of Rehmannia glutinosa. Their structures were established from the spectroscopic data obtained and by chemical evidence. The known verbascose (8) and stachyose (9) were also obtained in the current investigation, and the structure of stachyose was unequivocally defined using X-ray diffraction data. Compounds 1-9 were tested for their cytotoxicity against five human tumor cell lines, influence on dopamine receptor activation, and proliferation effects against Lactobacillus reuteri.


Assuntos
Rehmannia , Humanos , Rehmannia/química , Linhagem Celular , Raízes de Plantas/química
9.
J Asian Nat Prod Res ; : 1-9, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39329329

RESUMO

Three new cyclopentanoid monoterpenes, neopiscrocins A-C (1-3), together with 14 known compounds (4-17), were isolated from the roots of Picrorhiza scrophulariiflora. The structres of these compounds were elucidated on the basis of their spectroscopic data. All compounds were evaluated for cytotoxicity against six human tumor cell lines (PC9, PANC1, HCT-116, Hep-G2, BGC-823, and MCF-7), hepatoprotective activity and anti-inflammatory activity.

10.
Environ Sci Technol ; 57(38): 14113-14126, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37709662

RESUMO

Some key low-carbon technologies, ranging from wind turbines to electric vehicles, are underpinned by the strong rare-earth-based permanent magnets of the Nd, Pr (Dy)-Fe-Nb type (NdFeB). These NdFeB magnets, which are sensitive to demagnetization with temperature elevation (the Curie point), require the addition of variable amounts of dysprosium (Dy), where an elevation of the Curie point is needed to meet operational conditions. Given that China is the world's largest REE supplier with abundant REE reserves, the impact of an ambitious 1.5 °C climate target on China's Dy supply chain has sparked widespread concern. Here, we explore future trends and innovation strategies associated with the linkage between Dy and NdFeBs under various climate scenarios in China. We find China alone is expected to exhaust the global present Dy reserve within the next 2-3 decades to facilitate the 1.5 °C climate target. By implementing global available innovation strategies, such as material substitution, reduction, and recycling, it is possible to avoid 48%-68% of China's cumulative demand for Dy. Nevertheless, ongoing efforts in REE exploration and production are still required to meet China's growing Dy demand, which will face competition from the United States, European Union, and other countries with ambitious climate targets. Thus, our analysis urges China and those nations to form wider cooperation in REE supply chains as well as in NdFeB innovation for the realization of a global climate-safe future.


Assuntos
Disprósio , Metais Terras Raras , Clima , Imãs , China
11.
Fa Yi Xue Za Zhi ; 39(2): 168-175, 2023 Apr 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-37277380

RESUMO

Given the complexity of biological samples and the trace nature of target materials in forensic trace analysis, a simple and effective method is needed to obtain sufficient target materials from complex substrates. Magnetic nanoparticles (MNPs) have shown a wide range of application value in many research fields, such as biomedicine, drug delivery and separation, due to their unique superparamagnetic properties, stable physical and chemical properties, biocompatibility, small size, high specific surface area and other characteristics. To apply MNPs in the pretreatment of forensic materials, maximize the extraction rate of the target materials, and minimize interference factors to meet the requirements of trace analysis of the target materials, this paper reviews the application of MNPs in the fields of forensic toxicological analysis, environmental forensic science, trace evidence analysis and criminal investigation in recent years, and provides research ideas for the application of MNPs in forensic trace analysis.


Assuntos
Nanopartículas de Magnetita , Nanopartículas de Magnetita/química , Medicina Legal , Ciências Forenses , Toxicologia Forense
12.
J Asian Nat Prod Res ; 24(10): 905-924, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36111695

RESUMO

The new natural products reported in 2021 in peer-reviewed articles in journals with good reputations were reviewed and analyzed. The advances made by Asian research groups in the field of natural products chemistry in 2021 were summarized. Compounds with unique structural features and/or promising bioactivities originating from Asian natural sources were discussed based on their structural classification.


Assuntos
Produtos Biológicos , Produtos Biológicos/química , Estrutura Molecular , Inquéritos e Questionários
13.
J Asian Nat Prod Res ; 24(10): 945-954, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36052849

RESUMO

As part of an ongoing project on Rehmannia species, three new pyridine alkaloides (glutinosines A - C), and one new iridoid analogue (rehmaglutin E), were isolated from the leaves of Rehmannia glutinosa. The structures of the new compounds were established by extensive spectroscopic analysis and electronic circular dichroism calculations.


Assuntos
Alcaloides , Rehmannia , Rehmannia/química , Iridoides , Estrutura Molecular , Folhas de Planta/química , Alcaloides/análise , Piridinas
14.
J Asian Nat Prod Res ; 24(10): 955-962, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35852115

RESUMO

Four new ionones and ionone glycosides (1-4) were isolated from the whole plant of Rehmannia piasezkii Maxim. Their planar structures as well as absolute configuration were confirmed via spectroscopic analysis, ECD calculation, and X-ray crystallography. Compounds 1-4 were tested for their cytotoxicity against five human tumor cell lines and ability to inhibit LPS-activated NO production in the BV2 cell line.


Assuntos
Rehmannia , Humanos , Rehmannia/química , Norisoprenoides/química , Glicosídeos/farmacologia , Glicosídeos/química , Estrutura Molecular , Linhagem Celular Tumoral
15.
Fetal Pediatr Pathol ; 41(3): 499-504, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33213248

RESUMO

Background: Extraskeletal Ewing's Sarcoma (EES) may harbor more than one tumor-specific genetic abnormality, leading to diagnostic difficulties. Case report: We report a nine-year-old boy with recurrent mass of his right thigh. Tumor cells were round, with scant cytoplasm, finely dispersed chromatin, and inapparent, small nucleoli. The initial misdiagnosis was T-lymphoblastic lymphoma due to CD7 and TCR/Ig monoclonal rearrangement. As it expressed NKX2.2 and harbored an EWSR1-FLI1 fusion transcript, the diagnosis was changed to EES. The child underwent EES therapy with good initial response, but had a subcutaneous relapse at 22 months. Conclusion: In addition to typical genetic alterations, Ewing sarcoma can also express CD7 and TCR/Ig rearrangement, which are not limited to lymphoma.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras , Sarcoma de Ewing , Criança , Humanos , Imunoglobulinas , Masculino , Recidiva Local de Neoplasia , Receptores de Antígenos de Linfócitos T , Sarcoma de Ewing/diagnóstico , Sarcoma de Ewing/genética , Sarcoma de Ewing/patologia
16.
Support Care Cancer ; 29(9): 5435-5445, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33704565

RESUMO

PURPOSE: Breast cancer-related lymphedema (BCRL) is a major long-term complication for post-surgery breast cancer survivors. Although several risk factors have been identified, lifestyle characteristics have been neglected in previous studies. The aim of this study was to develop and validate a nomogram for estimating this population's risk of developing lymphedema, taking into consideration their demographic, clinical, and personal lifestyle behaviors. METHODS: In a cross-sectional study, we collected data from 775 post-operative breast cancer survivors who had attended a follow-up session in the recent 10 years (primary cohort). Lymphedema was assessed using the Norman telephone questionnaire, self-reported by patients. Multiple logistic regression was used to identify risk factors for lymphedema, including demographic, clinical, and lifestyle-related factors. A nomogram was constructed based on those factors and was validated using a separate group of 314 breast cancer patients (validation cohort). RESULTS: The factors independently associated with lymphedema were higher body mass index (BMI), modified radical mastectomy (MRM), postsurgical infection, chemotherapy, radiotherapy, exercise of the affected arm, and the active participation in physical activity (P<0.05). The area under the curve (AUC) values of the primary and the validation cohorts were 0.721 (95% confidence interval: 0.685-0.756) and 0.702 (95% confidence interval: 0.646-0.759), respectively. CONCLUSIONS: BCRL risk factors include MRM, radiotherapy, chemotherapy, and higher BMI, while the active physical activity behavior of patients appears to be a factor against lymphedema. The nomogram incorporating the patients' clinical and lifestyle factors might be useful for predicting lymphedema in breast cancer survivors.


Assuntos
Linfedema Relacionado a Câncer de Mama , Neoplasias da Mama , Sobreviventes de Câncer , Linfedema , Linfedema Relacionado a Câncer de Mama/epidemiologia , Linfedema Relacionado a Câncer de Mama/etiologia , Neoplasias da Mama/cirurgia , China , Estudos Transversais , Feminino , Humanos , Linfedema/epidemiologia , Linfedema/etiologia , Mastectomia , Nomogramas
17.
J Asian Nat Prod Res ; 23(12): 1115-1134, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34825847

RESUMO

The new natural products reported in 2020 in peer-reviewed articles in journals with good reputations were reviewed and analyzed. The advances made by Asian research groups in the field of natural products chemistry in 2020 were summarized. Compounds with unique structural features and/or promising bioactivities originating from Asian natural sources were discussed based on their structural classification.


Assuntos
Produtos Biológicos , Estrutura Molecular , Inquéritos e Questionários
18.
Molecules ; 26(7)2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33808108

RESUMO

Solvothermal synthesis of multiple dihydropyrimidinones at a time has been developed in inexpensive and green bio-based solvent lactic acid without any additional catalysts or additives. By this method, thirty new dihydropyrimidinone derivatives were synthesized in two batches and characterized. All of the compounds were screened by Eg5 motor protein ATPase assay, and the positive compounds were tested against the Caco-2 cell line, HeLa cell line, L929 cell line and T24 cell line in vitro. Among them, compound C9 exhibited the best inhibitory activity against motor protein ATPase with an IC50 value of 30.25 µM and significant cytotoxic activity in the micromolar range against the cells above. The Lineweaver-Burk plot revealed that compound C9 was a mixed-type Eg5 inhibitor. A molecular modeling study using the Discovery Studio program was performed, where compound C9 exhibited good binding interaction with Eg5 motor protein ATPase, and this was consistent with the attained experimental results.


Assuntos
Antineoplásicos , Proliferação de Células/efeitos dos fármacos , Cinesinas , Pirimidinonas , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Cinesinas/antagonistas & inibidores , Cinesinas/metabolismo , Camundongos , Estrutura Molecular , Ligação Proteica , Pirimidinonas/síntese química , Pirimidinonas/química , Pirimidinonas/farmacologia , Relação Estrutura-Atividade
19.
J Asian Nat Prod Res ; 22(12): 1101-1120, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33207951

RESUMO

The new natural products reported in 2019 in peer-reviewed articles in journals with good reputations were reviewed and analyzed. The advances made by Asian research groups in the field of natural products chemistry in 2019 were summarized. Compounds with unique structural features and/or promising bioactivities originating from Asian natural sources were discussed based on their structural classification.


Assuntos
Produtos Biológicos , Estrutura Molecular , Inquéritos e Questionários
20.
Lancet Oncol ; 20(11): e619-e626, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31674320

RESUMO

As a result of recent, substantial capacity building, a new landscape for cancer drug trials is emerging in China. However, data on the characteristics of cancer drug trials, and how they have changed over time, are scarce. Based on clinical trials published on the China Food and Drug Administration Registration and Information Disclosure Platform for Drug Clinical Studies, we aimed to systematically review changes over time in clinical trials of cancer drugs in mainland China from 2009 to 2018, to provide insight on the effectiveness of the pharmaceutical industry and identify unmet clinical needs of stakeholders. A total of 1493 trials of 751 newly tested cancer drugs were initiated. Increases over time were observed for the annual number of initiated trials, newly tested drugs, and newly added leading clinical trial units, with a sharp increase after 2016. Of the 1385 trials in which cancer types were identified, solid tumours (325 [23%] trials), non-small-cell lung cancer (232 [17%]), and lymphoma (126 [9%]) were the most common. A markedly uneven distribution was also observed in the geography of leading units with the largest number of leading units located in east China (50 [41%]) and the smallest number located in southwest China (4 [3%]). The growth trends we observed illustrate the progress in and increasing capability of cancer drug research and development achieved in mainland China over the decade from 2009. The low number of clinical trials on tumours with epidemiological characteristics unique to the Chinese population and the unbalanced geographical distribution of leading clinical trial units will provide potential targets for policy makers and other stakeholders. Further research efforts should address cancers uniquely relevant to Chinese populations, globally rare cancers, and the balance between equitable drug access, efficiency, and sustainability of cancer drug research and development in mainland China.


Assuntos
Antineoplásicos/uso terapêutico , Ensaios Clínicos como Assunto , Desenvolvimento de Medicamentos/tendências , Oncologia/tendências , Neoplasias/tratamento farmacológico , Projetos de Pesquisa/tendências , Antineoplásicos/efeitos adversos , China/epidemiologia , Difusão de Inovações , Humanos , Neoplasias/diagnóstico , Neoplasias/epidemiologia , Fatores de Tempo , Resultado do Tratamento
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