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1.
Cell ; 182(5): 1271-1283.e16, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32795413

RESUMO

There is an urgent need for vaccines against coronavirus disease 2019 (COVID-19) because of the ongoing SARS-CoV-2 pandemic. Among all approaches, a messenger RNA (mRNA)-based vaccine has emerged as a rapid and versatile platform to quickly respond to this challenge. Here, we developed a lipid nanoparticle-encapsulated mRNA (mRNA-LNP) encoding the receptor binding domain (RBD) of SARS-CoV-2 as a vaccine candidate (called ARCoV). Intramuscular immunization of ARCoV mRNA-LNP elicited robust neutralizing antibodies against SARS-CoV-2 as well as a Th1-biased cellular response in mice and non-human primates. Two doses of ARCoV immunization in mice conferred complete protection against the challenge of a SARS-CoV-2 mouse-adapted strain. Additionally, ARCoV is manufactured as a liquid formulation and can be stored at room temperature for at least 1 week. ARCoV is currently being evaluated in phase 1 clinical trials.


Assuntos
RNA Mensageiro/genética , RNA Viral/genética , Vacinas Sintéticas/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Sítios de Ligação , Vacinas contra COVID-19 , Chlorocebus aethiops , Infecções por Coronavirus/genética , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Feminino , Células HEK293 , Células HeLa , Humanos , Imunogenicidade da Vacina , Injeções Intramusculares , Macaca fascicularis , Masculino , Camundongos , Camundongos Endogâmicos ICR , Nanopartículas/química , RNA Mensageiro/metabolismo , RNA Viral/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Células Th1/imunologia , Potência de Vacina , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Células Vero , Vacinas Virais/administração & dosagem , Vacinas Virais/genética
2.
Opt Express ; 32(2): 1325-1333, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38297687

RESUMO

We demonstrate high-harmonic generation for the time-domain observation of the electric field (HHG-TOE) and use it to measure the waveform of ultrashort mid-infrared (MIR) laser pulses interacting with ZnO thin-films or WS2 monolayers. The working principle relies on perturbing HHG in solids with a weak replica of the pump pulse. We measure the duration of few-cycle pulses at 3200 nm, in reasonable agreement with the results of established pulse characterization techniques. Our method provides a straightforward approach to accurately characterize femtosecond laser pulses used for HHG experiments right at the point of interaction.

3.
Molecules ; 29(12)2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38930893

RESUMO

The growing demand for wearable and attachable displays has sparked significant interest in flexible quantum-dot light-emitting diodes (QLEDs). However, the challenges of fabricating and operating QLEDs on flexible substrates persist due to the lack of stable and low-temperature processable charge-injection/-transporting layers with aligned energy levels. In this study, we utilized NiOx nanoparticles that are compatible with flexible substrates as a hole-injection layer (HIL). To enhance the work function of the NiOx HIL, we introduced a self-assembled dipole modifier called 4-(trifluoromethyl)benzoic acid (4-CF3-BA) onto the surface of the NiOx nanoparticles. The incorporation of the dipole molecules through adsorption treatment has significantly changed the wettability and electronic characteristics of NiOx nanoparticles, resulting in the formation of NiO(OH) at the interface and a shift in vacuum level. The alteration of surface electronic states of the NiOx nanoparticles not only improves the carrier balance by reducing the hole injection barrier but also prevents exciton quenching by passivating defects in the film. Consequently, the NiOx-based red QLEDs with interfacial modification demonstrate a maximum current efficiency of 16.1 cd/A and a peak external quantum efficiency of 10.3%. This represents a nearly twofold efficiency enhancement compared to control devices. The mild fabrication requirements and low annealing temperatures suggest potential applications of dipole molecule-modified NiOx nanoparticles in flexible optoelectronic devices.

4.
Semin Cancer Biol ; 86(Pt 3): 400-407, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35183412

RESUMO

Colon cancer is a major human cancer accounting for about a tenth of all cancer cases thus making it among the top three cancers in terms of incidence as well as mortality. Metastasis to distant organs, particularly to liver, is the primary reason for associated mortality. Chemokines, the chemo-attractants for various immune cells, have increasingly been reported to be involved in cancer initiation and progression, including in colon cancer. Here we discuss the available knowledge on the role of several chemokines, such as, CCL2, CCL3, CCL5, CXCL1, CXCL2, CXCL8 in colon cancer progression. CCL20 is one chemokine with emerging evidence for its role in influencing colon cancer tumor microenvironment through the documents effects on fibroblasts, macrophages and immune cells. We focus on CCL20 and its receptor CCR6 as promising factors that affect multiple levels of colon cancer progression. They interact with several cytokines and TLR receptors leading to increased aggressiveness, as supported by multitude of evidence from in vitro, in vivo studies as well as human patient samples. CCL20-CCR6 bring about their biological effects through regulation of several signaling pathways, including, ERK and NF-κB pathways, in addition to the epithelial-mesenchymal transition. Signaling involving CCL20-CCR6 has profound effect on colon cancer hepatic metastasis. Combined with elevated CCL20 levels in colon tumors and metastatic patients, the above information points to a need for further evaluation of chemokines as diagnostic and/or prognostic biomarkers.


Assuntos
Quimiocinas , Neoplasias do Colo , Humanos , Neoplasias do Colo/genética , Neoplasias Hepáticas/secundário , NF-kappa B/metabolismo , Transdução de Sinais , Microambiente Tumoral/genética
5.
New Phytol ; 237(1): 265-278, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36131553

RESUMO

Caterpillar oral secretion (OS) contains active molecules that modulate plant defense signaling. We isolated an effector-like protein (Highly Accumulated Secretory Protein 1, HAS1) from cotton bollworm (Helicoverpa armigera) that is the most highly accumulated secretory protein of the nondigestive components in OS and belongs to venom R-like protein. Elimination of HAS1 by plant-mediated RNA interference reduced the suppression of OS on the defense response in plants. Plants expressing HAS1 are more susceptible to insect herbivory accompanied by the reduced expressions of multiple defense genes. HAS1 binds to the basic helix-loop-helix (bHLH) transcription factors, including GoPGF involved in pigmented gland formation and defense compounds biosynthesis in cotton and MYC3/MYC4 the main regulators in jasmonate (JA) signaling in Arabidopsis. The binding activity is required for HAS1 to inhibit the activation of bHLHs on plant defense gene expressions. Together with our previous study that another venom R-like protein HARP1 in cotton bollworm OS blocks JA signaling by interacting with JASMONATE-ZIM-domain repressors, we conclude that the venom R-like proteins in OS interfere with plant defense in a dual suppression manner. Considering the venom proteins in parasitic wasp assault the immune system of its host animal, our investigation reveals their conserved function in carnivorous and herbivorous insects.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Mariposas , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Transativadores/metabolismo , Proteínas Repressoras/metabolismo , Oxilipinas/metabolismo , Ciclopentanos/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Plantas/metabolismo , Gossypium/genética , Gossypium/metabolismo
6.
Ann Surg Oncol ; 30(7): 4014-4025, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36566257

RESUMO

BACKGROUND: Although the incidence of adenocarcinoma of the esophagogastric junction (AEG) has been increasing since the past decade, the proportion of AEG cases in two previous clinical trials (ACTS-GC and CLASSIC) that investigated the efficacy of adjuvant chemotherapy was relatively small. Therefore, whether AEG patients can benefit from adjuvant chemotherapy remains unclear. METHODS: Patients who were diagnosed with pathological stage II/III, Siewert II/III AEG, and underwent curative surgery at three high-volume institutions were assessed. Clinical outcomes were analyzed by using Kaplan-Meier curves, log-rank test, and Cox regression model. Propensity score matching (PSM) was used to reduce the selection bias. RESULTS: A total of 927 patients were included (the chemotherapy group: 696 patients; the surgery-only group: 231 patients). The median follow-up was 39.0 months. The 5-year overall survival was 63.1% (95% confidence interval [CI]: 59.0-67.6%) for the chemotherapy group and 50.2% in the surgery-only group (hazard ratio [HR] = 0.69, 95% CI: 0.54-0.88; p = 0.003). The 5-year, disease-free survival was 35.4% for the chemotherapy group and 16.6% for the surgery-only group (HR = 0.66, 95% CI: 0.53-0.83; p < 0.001). After PSM, the survival benefit of adjuvant chemotherapy for AEG was maintained. Multivariate analysis for overall survival and disease-free survival further demonstrated the survival benefit of adjuvant chemotherapy, with HRs of 0.63 (p < 0.001) and 0.52 (p < 0.001), respectively. CONCLUSIONS: Postoperative adjuvant chemotherapy was associated with improved overall survival and disease-free survival in patients with operable stage II or III AEG after D2 gastrectomy.


Assuntos
Adenocarcinoma , Neoplasias Gástricas , Humanos , Estudos Retrospectivos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/cirurgia , Junção Esofagogástrica/cirurgia , Junção Esofagogástrica/patologia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/cirurgia , Gastrectomia , Quimioterapia Adjuvante
7.
Plant Cell ; 32(1): 226-241, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31649122

RESUMO

Age and wounding are two major determinants for regeneration. In plants, the root regeneration is triggered by wound-induced auxin biosynthesis. As plants age, the root regenerative capacity gradually decreases. How wounding leads to the auxin burst and how age and wound signals collaboratively regulate root regenerative capacity are poorly understood. Here, we show that the increased levels of three closely-related miR156-targeted Arabidopsis (Arabidopsis thaliana) SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) transcription factors, SPL2, SPL10, and SPL11, suppress root regeneration with age by inhibiting wound-induced auxin biosynthesis. Mechanistically, we find that a subset of APETALA2/ETHYLENE RESPONSE FACTOR (AP2/ERF) transcription factors including ABSCISIC ACID REPRESSOR1 and ERF109 is rapidly induced by wounding and serves as a proxy for wound signal to induce auxin biosynthesis. In older plants, SPL2/10/11 directly bind to the promoters of AP2/ERFs and attenuates their induction, thereby dampening auxin accumulation at the wound. Our results thus identify AP2/ERFs as a hub for integration of age and wound signal for root regeneration.


Assuntos
Proteínas de Arabidopsis/metabolismo , Etilenos/metabolismo , Proteínas de Homeodomínio/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Regeneração/fisiologia , Ácido Abscísico/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Homeodomínio/genética , Ácidos Indolacéticos/metabolismo , MicroRNAs/metabolismo , Proteínas Nucleares , Regiões Promotoras Genéticas , Regeneração/genética , Proteínas Repressoras , Fatores de Transcrição/metabolismo
8.
Mol Psychiatry ; 27(8): 3214-3222, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35668158

RESUMO

Infectious disease epidemics have become more frequent and more complex during the 21st century, posing a health threat to the general public and leading to psychological symptoms. The current study was designed to investigate the prevalence of and risk factors associated with depression, anxiety and insomnia symptoms during epidemic outbreaks, including COVID-19. We systematically searched the PubMed, Embase, Web of Science, OVID, Medline, Cochrane databases, bioRxiv and medRxiv to identify studies that reported the prevalence of depression, anxiety or insomnia during infectious disease epidemics, up to August 14th, 2020. Prevalence of mental symptoms among different populations including the general public, health workers, university students, older adults, infected patients, survivors of infection, and pregnant women across all types of epidemics was pooled. In addition, prevalence of mental symptoms during COVID-19 was estimated by time using meta-regression analysis. A total of 17,506 papers were initially retrieved, and a final of 283 studies met the inclusion criteria, representing a total of 948,882 individuals. The pooled prevalence of depression ranged from 23.1%, 95% confidential intervals (95% CI: [13.9-32.2]) in survivors to 43.3% (95% CI: [27.1-59.6]) in university students, the pooled prevalence of anxiety ranged from 25.0% (95% CI: [12.0-38.0]) in older adults to 43.3% (95% CI: [23.3-63.3]) in pregnant women, and insomnia symptoms ranged from 29.7% (95% CI: [24.4-34.9]) in the general public to 58.4% (95% CI: [28.1-88.6]) in university students. Prevalence of moderate-to-severe mental symptoms was lower but had substantial variation across different populations. The prevalence of mental problems increased over time during the COVID-19 pandemic among the general public, health workers and university students, and decreased among infected patients. Factors associated with increased prevalence for all three mental health symptoms included female sex, and having physical disorders, psychiatric disorders, COVID infection, colleagues or family members infected, experience of frontline work, close contact with infected patients, high exposure risk, quarantine experience and high concern about epidemics. Frequent exercise and good social support were associated with lower risk for these three mental symptoms. In conclusion, mental symptoms are common during epidemics with substantial variation across populations. The population-specific psychological crisis management are needed to decrease the burden of psychological problem and improve the mental wellbeing during epidemic.


Assuntos
COVID-19 , Doenças Transmissíveis , Distúrbios do Início e da Manutenção do Sono , Gravidez , Feminino , Humanos , Idoso , COVID-19/epidemiologia , Pandemias , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Prevalência , Depressão/epidemiologia , Depressão/etiologia , SARS-CoV-2 , Ansiedade/epidemiologia , Ansiedade/etiologia , Fatores de Risco , Doenças Transmissíveis/epidemiologia
9.
Inorg Chem ; 62(46): 19043-19051, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37939347

RESUMO

Natural gas plays a crucial role in daily and industrial production, but the impurities contained in natural gas limit its further use. It is very important to develop adsorbents that can separate CH4 from multicomponent mixtures, but there are still many challenges and problems. Herein, a novel porous MOF {[Mn5(pbdia)2(CO3)(H2O)2] ↔ 5H2O ↔ 2DMF}n (pbdia = 2,2'-(5-carboxy-1,3-phenylene)bis(oxy) diterephthalic acid) was successfully synthesized based on a flexible pentacarboxylic acid ligand and a unique pentanuclear Mn5(COO)10CO3 cluster. The MOF reveals a 3D porous structure with 2D intersecting channels, which shows high C3H8, C2H6, and CO2 adsorption capacities and affinities over CH4. Moreover, the ideal adsorption solution theory selectivities of C3H8/CH4, C2H6/CH4, and CO2/CH4 can reach 263.0, 27.0, and 7.7, respectively, suggesting a potential for removing the low content of C3H8, C2H6, and CO2 from pipeline natural gas, which was further confirmed by breakthrough curves and GCMC simulations.

10.
Zhongguo Zhong Yao Za Zhi ; 48(17): 4675-4685, 2023 Sep.
Artigo em Zh | MEDLINE | ID: mdl-37802806

RESUMO

The Compound Cheqian Tablets are derived from Cheqian Power in Comprehensive Recording of Divine Assistance, and they are made by modern technology with the combination of Plantago asiatica and Coptis chinensis. To investigate the material basis of Compound Cheqian Tablets in the treatment of diabetic nephropathy, in this study, the chemical components of Compound Cheqian Tablets were characterized and analyzed by UPLC-Q-TOF-MS/MS, and a total of 48 chemical components were identified. The identified chemical compounds were analyzed by network pharmacology. By validating with previous literature, six bioactive compounds including acteoside, isoacteoside, coptisine, magnoflorine, palmatine, and berberine were confirmed as the index components for qua-lity evaluation. Furthermore, the content of the six components in the Compound Cheqian Tablets was determined by the "double external standards" quantitative analysis of multi-components by single marker(QAMS), and the relative correction factor of isoacteoside was calculated as 1.118 by using acteoside as the control; the relative correction factors of magnoflorine, palmatine, and berberine were calculated as 0.729, 1.065, and 1.126, respectively, by using coptisine as the control, indicating that the established method had excellent stability under different conditions. The results obtained by the "double external standards" QAMS approximated those obtained by the external standard method. This study qualitatively characterized the chemical components in the Compound Cheqian Tablets by applying UPLC-Q-TOF-MS/MS and screened the pharmacodynamic substance basis for the treatment of diabetic nephropathy via network pharmacology, and primary pharmacodynamic substance groups were quantitatively analyzed by the "double external stan-dards" QAMS method, which provided a scientific basis for clarifying the pharmacodynamic substance basis and quality control of Compound Cheqian Tablets.


Assuntos
Berberina , Nefropatias Diabéticas , Medicamentos de Ervas Chinesas , Humanos , Espectrometria de Massas em Tandem , Berberina/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Farmacologia em Rede , Medicamentos de Ervas Chinesas/química , Controle de Qualidade , Comprimidos
11.
Ann Surg Oncol ; 29(13): 8214-8224, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35798893

RESUMO

BACKGROUND: The benefit of adjuvant chemotherapy (AC) for patients with stage II gastric cancer remains controversial. This study aimed to explore the indications for adjuvant chemotherapy in patients with stage II gastric cancer by constructing an individual prediction model. PATIENTS AND METHODS: In this Chinese multicenter study, a total of 1012 patients with stage II gastric cancer after D2 radical gastrectomy were retrospectively analyzed. All patients were randomly assigned to a training cohort (n = 674) or a validation cohort (n = 338). A nomogram was constructed according to the training cohort. Concordance index (C-index), the area under the receiver operating characteristic (ROC) curves (AUC), calibration curves, and decision curve analysis (DCA) were applied to evaluate the performance of the nomogram. ROC curves and stratified survival were used to determine the patients' cutoff score for a benefit from adjuvant chemotherapy. An additional 338 patients were used as a validation cohort to validate the feasibility of using this nomogram to guide individualized therapy for patients with stage II gastric cancer. RESULTS: Univariate and multivariate analyses illustrated that age, sex, tumor location, size, carcinoembryonic antigen (CEA), hemoglobin (HB), and T stage were independent prognostic factors for overall survival (OS), and they were used to establish a nomogram. The cutoff value was determined by ROC curve analysis, and patients were divided into a high-risk group (< 239 points) and a low-risk group (≥ 239 points). There was no significant difference in the OS of low-risk patients in either the training cohort or the validation cohort. However, the OS of high-risk patients in the AC group was better than that of patients in the surgery-only group. CONCLUSIONS: This prediction model can be applied to guide treatment of patients with stage II gastric cancer. High-risk patients (< 239 points) are likely to benefit from AC after D2 radical gastrectomy.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/cirurgia , Estudos Retrospectivos , Gastrectomia/efeitos adversos , Quimioterapia Adjuvante , Nomogramas , China
12.
Ann Surg Oncol ; 29(4): 2324-2331, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34796431

RESUMO

BACKGROUND: Mismatch repair-deficient (dMMR) or microsatellite instability-high (MSI-H) status serves as a predictor of a poor response to adjuvant chemotherapy among stage 2 colon cancer patients. This study aimed to investigate the efficacy of adjuvant chemotherapy in dMMR/MSI-H gastric cancer (GC). METHODS: Clinical studies comparing adjuvant chemotherapy and surgery alone in dMMR/MSI-H GCs through June 2021 were retrieved to assess the survival of patients managed with both treatments. Two approaches were used to pool the hazard ratio (HR) of survival: (1) if Kaplan-Meier curves and number of patients at risk were provided, individual patient data were extracted. Cox models were used to calculate the HR with its 95% confidence interval (CI); (2) for study-level data, pooled HR was estimated using fixed/random-effects models. RESULTS: Seven clinical studies were assessed. For dMMR/MSI-H versus mismatch repair-proficient (pMMR)/microsatellite stable (MSS)/microsatellite instability-low (MSI-L) status, the estimated 5-year disease-free survival (DFS) rate was 74.2% versus 51.5% (HR, 0.44; 95% CI, 0.32-0.62; P < 0.001) and the estimated 5-year OS rate was 60.5% versus 49.1% (HR, 0.71; 95% CI, 0.60-0.85; P < 0.001). The study-level data showed pooled HRs of 0.42 for DFS (95% CI, 0.31-0.57; P < 0.001) and 0.65 for OS (95% CI, 0.38-1.11; P = 0.114). For adjuvant chemotherapy versus observation of dMMR/MSI-H, the estimated 5-year DFS rate was 76.1% versus 73.3% (HR, 0.72; 95% CI, 0.45-1.15; P = 0.171) and the estimated 5-year OS rate was 73.5% versus 59.7% (HR, 0.62; 95% CI, 0.46-0.83; P = 0.001). Significant survival differences also were observed at study level. CONCLUSIONS: The study findings confirm the benefit of adjuvant chemotherapy for dMMR/MSI-H GC patients.


Assuntos
Instabilidade de Microssatélites , Neoplasias Gástricas , Neoplasias Encefálicas , Quimioterapia Adjuvante , Neoplasias Colorretais , Reparo de Erro de Pareamento de DNA , Humanos , Estadiamento de Neoplasias , Síndromes Neoplásicas Hereditárias , Prognóstico , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética
13.
Phys Chem Chem Phys ; 24(41): 25648-25655, 2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36255301

RESUMO

Taking Cs2NaBiCl6, Cs2AgInCl6 and Cs2AgBiCl6 as examples of lead-free double perovskites (DPs), we study the photoluminescence (PL) properties of Mn-doped DPs. The electron localization function (ELF) reveals the more ionic nature of the Na-Cl bond in Cs2NaBiCl6 than that of the Ag-Cl bond in Cs2AgBiCl6. Bader charge calculations confirm the nominal +2 valence state of Mn ions in both DPs. Mn2+ ions introduce two defect levels in the band gap of the Cs2NaBiCl6 host, accounting for the d-d transition (4T1-6A1 transition) of Mn2+ and thus the subsequent orange PL. The changes of the crystal field and their influences on the emission energy of Mn2+ ions in different DPs are evaluated by calculating the Racah parameters (B and C) and the crystal field strength (Dq) obtained from energies of the terms of d5 in the Cs2NaBiCl6:Mn2+ and Cs2AgInCl6:Mn2+ systems. The results show that Dq in Cs2AgInCl6:Mn2+ is stronger than that in Cs2NaBiCl6:Mn2+. The analyses on bonding interactions of the Mn-Cl bond via ELF and the integrated projected pCOHP also confirm the stronger ionic bonding interactions and thus the boost of the crystal field strength in the Cs2AgInCl6:Mn2+ system, which results in the blue-shift of the Mn2+ introduced PL peak from Cs2AgInCl6 to Cs2NaBiCl6. Our results provide a new strategy to modulate the emission wavelengths, i.e., tuning the crystal field.

14.
Proc Natl Acad Sci U S A ; 116(28): 14331-14338, 2019 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-31221756

RESUMO

Insects have evolved effectors to conquer plant defense. Most known insect effectors are isolated from sucking insects, and examples from chewing insects are limited. Moreover, the targets of insect effectors in host plants remain unknown. Here, we address a chewing insect effector and its working mechanism. Cotton bollworm (Helicoverpa armigera) is a lepidopteran insect widely existing in nature and severely affecting crop productivity. We isolated an effector named HARP1 from H. armigera oral secretion (OS). HARP1 was released from larvae to plant leaves during feeding and entered into the plant cells through wounding sites. Expression of HARP1 in Arabidopsis mitigated the global expression of wounding and jasmonate (JA) responsive genes and rendered the plants more susceptible to insect feeding. HARP1 directly interacted with JASMONATE-ZIM-domain (JAZ) repressors to prevent the COI1-mediated JAZ degradation, thus blocking JA signaling transduction. HARP1-like proteins have conserved function as effectors in noctuidae, and these types of effectors might contribute to insect adaptation to host plants during coevolution.


Assuntos
Gossypium/genética , Interações Hospedeiro-Parasita/genética , Mariposas/patogenicidade , Doenças das Plantas/genética , Animais , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Ciclopentanos/metabolismo , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas/genética , Gossypium/crescimento & desenvolvimento , Gossypium/parasitologia , Mariposas/metabolismo , Oxilipinas/metabolismo , Doenças das Plantas/parasitologia , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Transdução de Sinais/genética
15.
J Asian Nat Prod Res ; : 1-7, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672871

RESUMO

Two undescribed stilbenoid diglycosides, dendrosonside A and dendrosonside B (1 and 2), were isolated from the stems of Dendrobium 'Sonia'. Their structures were elucidated based on 1 D/2D NMR and HRESIMS. The glycosyls contained in the two isolates were determined as D-glucose by acid hydrolysis and GC-MS analyses. In addition, 1 and 2 were further tested for the inhibition of nitric oxide production.

16.
Mo Med ; 119(1): 49-54, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36033149

RESUMO

Among individuals of African and Latinx descent compared to those of European background, there is a higher prevalence, earlier onset, more rapid progression of primary open angle glaucoma and greater incidence of blindness. Although some suggest that outreach, education and screening programs may expand earlier diagnosis, and attention to access, cost of treatment, and adherence will improve outcomes, there is increasing evidence of genetic and physiologic differences which may be associated with these disease disparities.


Assuntos
Glaucoma de Ângulo Aberto , Glaucoma , Cegueira , Humanos , Pressão Intraocular , Grupos Raciais
17.
Angew Chem Int Ed Engl ; 61(22): e202201064, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35293123

RESUMO

An efficient approach for asymmetric synthesis of planar-chiral macrocycles (paracyclophanes) has been disclosed through enantioselective electrophilic aromatic aminations with azodicarboxylates enabled by chiral phosphoric acid catalysis. A wide range of chiral macrocycles bearing varied ring sizes (16 to 23-membered) and functional group-containing ansa chains were readily afforded using this method, with excellent yields and high enantioselectivities (23 examples, up to 99.5 : 0.5 er). Experimental studies and DFT calculations were performed to elucidate the mechanism and origin of stereoselectivities of these reactions. Preliminary utilization of the planar-chiral macrocycle as chiral organocatalyst showcased the potential applications of these novel chiral skeletons.

18.
BMC Gastroenterol ; 21(1): 363, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34620108

RESUMO

OBJECTIVE: The benefit of adjuvant chemotherapy is still controversial for stage II gastric cancer patients. This study aims to identify prognostic factors to guide individualized treatment for stage II gastric cancer patients. METHODS: We retrospectively reviewed 1121 stage II gastric cancer patients who underwent D2 radical gastrectomy from 2007 to 2017 in the Sixth Affiliated Hospital of Sun Yat-sen University, FuJian Medical School Affiliated Union Hospital and Sun Yat-sen University Cancer Center. Propensity score matching was used to ensure that the baseline data were balanced between the adjuvant chemotherapy group and surgery-only group. Kaplan-Meier survival and multivariate Cox regression analyses were carried out to identify independent prognostic factors. RESULTS: In univariate analysis, after propensity score matching, age, tumor location, tumor size, CEA, T stage and N stage were associated with overall survival (OS). Multivariate analysis illustrated that age ≥ 60 years old, linitis plastica and T4 were independent risk factors for OS, but lower location and adjuvant chemotherapy were protective factors. CONCLUSION: Stage II gastric cancer patients with adverse prognostic factors (age ≥ 60, linitis plastica and T4) have poor prognosis. Adjuvant chemotherapy may be more beneficial for these patients.


Assuntos
Neoplasias Gástricas , China , Gastrectomia , Humanos , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/cirurgia , Análise de Sobrevida
19.
Proc Natl Acad Sci U S A ; 115(23): E5410-E5418, 2018 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-29784821

RESUMO

Gossypol and related sesquiterpene aldehydes in cotton function as defense compounds but are antinutritional in cottonseed products. By transcriptome comparison and coexpression analyses, we identified 146 candidates linked to gossypol biosynthesis. Analysis of metabolites accumulated in plants subjected to virus-induced gene silencing (VIGS) led to the identification of four enzymes and their supposed substrates. In vitro enzymatic assay and reconstitution in tobacco leaves elucidated a series of oxidative reactions of the gossypol biosynthesis pathway. The four functionally characterized enzymes, together with (+)-δ-cadinene synthase and the P450 involved in 7-hydroxy-(+)-δ-cadinene formation, convert farnesyl diphosphate (FPP) to hemigossypol, with two gaps left that each involves aromatization. Of six intermediates identified from the VIGS-treated leaves, 8-hydroxy-7-keto-δ-cadinene exerted a deleterious effect in dampening plant disease resistance if accumulated. Notably, CYP71BE79, the enzyme responsible for converting this phytotoxic intermediate, exhibited the highest catalytic activity among the five enzymes of the pathway assayed. In addition, despite their dispersed distribution in the cotton genome, all of the enzyme genes identified show a tight correlation of expression. Our data suggest that the enzymatic steps in the gossypol pathway are highly coordinated to ensure efficient substrate conversion.


Assuntos
Gossipol/biossíntese , Gossipol/metabolismo , Vias Biossintéticas , Gossypium/metabolismo , Isomerases/biossíntese , Isomerases/metabolismo , Folhas de Planta/metabolismo , Sesquiterpenos Policíclicos , Sesquiterpenos/metabolismo , Transcriptoma/efeitos dos fármacos
20.
Mycorrhiza ; 31(2): 161-171, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33559745

RESUMO

Arbuscular mycorrhizal fungi (AMF) are suggested to be important for invasions by many exotic plants. However, it is not yet known how associations between AMF and invasive plant populations change in mountains ranges and how changed associations affect further expansion of different populations in new habitats. We conducted a field survey to detect AMF colonization rate of the invasive Galinsoga quadriradiata along an elevational gradient ranging from 223 to 1947 masl in the Qinling and Bashan Mountains, China. Additionally, a greenhouse experiment was conducted to compare plant growth performance among five elevational populations. In the field, total plant mass and seed production, as well as root AMF colonization rate, significantly decreased with elevation. When populations were grown in a novel soil environment in the greenhouse, the high-altitude populations achieved higher seed and total mass at lower AMF colonization rate than the low-altitude populations. Moreover, high AMF association was related to high intraspecific competition within low-altitude populations and limited seed production. Our results revealed that the associations between AMF and G. quadriradiata decrease with altitude in mountain ranges, and this may indicate that differentiation of association between AMF and elevational populations occurs during range expansion of G. quadriradiata. The results of the greenhouse experiment suggest that the high-altitude populations are more aggressive than the low-altitude populations in a non-stressful environment.


Assuntos
Micorrizas , Altitude , China , Raízes de Plantas , Plantas
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