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1.
PLoS Genet ; 17(7): e1009680, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34252082

RESUMO

The evolution of insecticide resistance represents a global constraint to agricultural production. Because of the extreme genetic diversity found in insects and the large numbers of genes involved in insecticide detoxification, better tools are needed to quickly identify and validate the involvement of putative resistance genes for improved monitoring, management, and countering of field-evolved insecticide resistance. The avermectins, emamectin benzoate (EB) and abamectin are relatively new pesticides with reduced environmental risk that target a wide number of insect pests, including the beet armyworm, Spodoptera exigua, an important global pest of many crops. Unfortunately, field resistance to avermectins recently evolved in the beet armyworm, threatening the sustainable use of this class of insecticides. Here, we report a high-quality chromosome-level assembly of the beet armyworm genome and use bulked segregant analysis (BSA) to identify the locus of avermectin resistance, which mapped on 15-16 Mbp of chromosome 17. Knockout of the CYP9A186 gene that maps within this region by CRISPR/Cas9 gene editing fully restored EB susceptibility, implicating this gene in avermectin resistance. Heterologous expression and in vitro functional assays further confirm that a natural substitution (F116V) found in the substrate recognition site 1 (SRS1) of the CYP9A186 protein results in enhanced metabolism of EB and abamectin. Hence, the combined approach of coupling gene editing with BSA allows for the rapid identification of metabolic resistance genes responsible for insecticide resistance, which is critical for effective monitoring and adaptive management of insecticide resistance.


Assuntos
Sistema Enzimático do Citocromo P-450/genética , Resistência a Inseticidas/genética , Spodoptera/genética , Animais , Mapeamento Cromossômico/métodos , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Edição de Genes/métodos , Genoma/genética , Inseticidas/farmacologia , Ivermectina/análogos & derivados , Ivermectina/farmacologia , Larva/genética , Spodoptera/metabolismo
2.
Artigo em Inglês | MEDLINE | ID: mdl-38581310

RESUMO

Here, we present a case of choriocarcinoma with metastasis only to the right inferior pulmonary vein and heart, which is unusual, as the skipping of lung metastasis is extremely rare. The 34-year-old patient presented with cough and hemoptysis. The diagnosis was challenging due to the absence of gynecological abnormalities and elevated ß-HCG levels, only revealing a cardiac mass upon imaging. While no abnormalities were found through gynecological ultrasound or gynecological examination, the serum human chorionic gonadotropin ß subunit (ß-HCG) level was abnormally raised. Echocardiography showed a left atrial myxoma with a size of approximately 6.3×1.81 cm. A left atrial mass resection was performed during cardiac surgery, where it was found that the left atrial mass had originated from the right inferior pulmonary vein. It was approximately 6×3×3 cm in size, with a flesh-red color and firm tissue. Postoperative pathology and immunohistochemistry indicated choriocarcinoma. The cardiac surgery unearthed a mass originating from the right inferior pulmonary vein. Its size and characteristics, along with the chemotherapy regimens that followed, are crucial details for understanding treatment approaches for such atypical cases. Highlight the patient's recovery post-treatment and the effectiveness of the chemotherapy regimen. This offers insights into the potential for successful treatment outcomes in atypical choriocarcinoma cases. The patient underwent chemotherapy regimens with etoposide, cisplatin (EP) ,etoposide, and methotrexate, and dactinomycin alternating with cyclophosphamide and vincristine (EMACO). A satisfactory result was achieved. This case enhances understanding of choriocarcinoma metastasis patterns. It underscores the need for a multidisciplinary approach in diagnosing and managing such rare presentations.

3.
Plant Dis ; 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38803070

RESUMO

Polygonatum kingianum is a Chinese herbal medicine that belongs to the genus Polygonatum of the family Liliaceae. In June 2023, Polygonatum kingianum Coll. et Hemsl. in nurseries in Qujing, Yunnan Province, China, showed irregular brown spots on the leaves, whole leaf necrosis, and plant death in serious cases, with an incidence of 10-20% (Fig. S1). To identify the pathogens of P. kingianum, six diseased samples were collected from nurseries with 0.6 acre. These diseased sample leaves were soaked in 0.1% HgCl2 for 1 min and 75% ethanol for 2 min and then rinsed thrice with sterile water. Treated leaves were cut into small pieces (5×5 mm) and cultured on potato dextrose agar (PDA) for five days at 28°C. Total thirteen fungal strains were isolated from PDA medium. The nuclear ribosomal internal transcribed spacer of ribosomal DNA (ITS rDNA) region of these 13 strains was amplified by polymerase chain reaction (PCR) using universal primers ITSI/ITS4 (White et al. 1990). Sequencing and BLAST of the ITS region on NCBI showed that 11 out of 13 fungal strains belonged to the genus Alternaria, with an identity ≥99%. We selected one of the Alternaria strains, HJ-A1, for further study. The HJ-A1 colony appeared grayish brown white-to-gray with a flocculent texture on the front side and a dark gray underside on the PDA medium (Fig. S1). The conidiophores appeared brown, either single or branched, and produced numerous short conidial chains. The conidia were obclavate to obpyriform or ellipsoid in shape and contained 1-4 transverse septa and 0-2 oblique septa. The conidial diameter was 27.30µm in length and 12.27µm in width. (Fig. S1). To further determine the species of HJA1, the genomic DNA of HJ-A1 was extracted using the Lysis Buffer for PCR (AG, Hunan, China). Four Alternaria genomic DNA regions including the ITS, translation elongation factor 1-α gene (TEF1-α), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and Alternaria major allergen gene (Alt a1) were amplified by PCR using the primers as previously reported (Woudenberg et al. 2013, Hong et al. 2005). Sequence analysis revealed that the ITS (484bp) of HJ-A1 (NCBI No. PP082633), TEF1-α (267bp) of HJ-A1 (NCBI No. PP419893), GAPDH (582bp) of HJ-A1 (NCBI No. PP419892), and Alt a1 (522bp) of HJ-A1 (NCBI No. PP228046) shared the highest identity with A. alternata respectively (99≥%). A maximum likelihood phylogenetic tree was constructed with the combined sequence data sets of ITS, GAPDH, TEF, and Alt a1 using MEGA 7. The results showed that HJ-A1 strain clustered with A. alternate (Fig. S2). The pathogenicity of HJ-A1 was tested according to Koch's postulates by inoculating HJ-A1 conidia suspension (2×105 conidia/mL) into leaves of 1-year-old P. kingianum, with sterile water as a control. Each treatment group included 3 plants with 3 replicates. The tested plants were planted in a phytotron at 28℃ and 90% humidity. Three days after inoculation, symptoms similar to those under natural conditions were observed in the HJ-A1-inoculated plants, whereas no symptoms were observed in the control plants (Fig. S1). The same fungal strains were re-isolated from inoculated leaves and identified by morphologically and sequence of ITS. Previous studies showed that Alternaria alternata funji cause many plant diseases, such as fig fruit rot (Latinovic N et al. 2014),daylily leaf spot (Huang D et al. 2022), fruit blight on sesame (Cheng H et al. 2021),leaf spot of Cynanchum atratum Bunge (Sun H et al. 2021) and so on. To our knowledge, this is the first report of A. alternata causing P. kingianum leaf spot in China. The discovery of this pathogen will help to guide the protection and control of P. kingianum disease.

4.
Opt Express ; 31(21): 34577-34588, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37859210

RESUMO

We propose a design of the compact high-resolution photonic crystal (PhC) spectrometer with a wide working bandwidth based on both super-prism and local-super-collimation (LSC) effects. The optimizing methods, finding the ideal incident angle and oblique angle of PhC for a wider working bandwidth and ideal incident beam width and PhC size for a certain resolution requirement, are developed. Besides the theoretical work, for the first time, the experiment of such a PhC spectrometer is conducted in the microwave frequency range, and the beam-splitting effects for different frequencies in a wide working bandwidth agree very well with the theoretical predictions. According to the scalability, with the condition to control the deviations in the fabrication processes the design could be extended to optical frequency ranges, e.g., infrared, visible-light, and ultraviolet ranges. The spectrometer in optical frequencies can be implemented on silicon-on-insulator (SOI) chips as a thin-slab structure so that the operating bandwidth can be expanded further through the multi-layer design. Theoretically, the size of the ultra-high-resolution PhC spectrometer in optical frequency ranges based on our design could be two orders smaller than the traditional design.

5.
Ecotoxicol Environ Saf ; 268: 115680, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37984290

RESUMO

To study the adverse effects of butyl benzyl phthalate (BBP) on Brachionus plicatilis, rotifers were exposed to different BBP concentrations (0 [control], 0.001, 0.01, 0.1, and 1 mg/L). We measured the activities of the antioxidant enzymes superoxide dismutase, catalase, and reduced glutathione, which play a key role in detoxification, and the malondialdehyde content, which represents the level of lipid peroxidation. In addition, we investigated the effect of BBP on the submicroscopic structure and transcriptome of rotifer ovary cells. Our results showed that B. plicatilis exhibited a rapid oxidative stress response accompanied by a significant increase in superoxide dismutase enzyme activity. High BBP concentrations resulted in a significant decrease in malondialdehyde content, which indicated that BBP interferes with the lipid metabolism of rotifer cells. Our observations showed that the endoplasmic reticulum structure of rotifer ovary cells was severely damaged by BBP exposure. Transcriptomic data further demonstrated that oxidative stress and cellular sub-microstructural damage were associated with altered expression of functional genes related to rotifer redox regulation, biosynthetic processes, and cellular damage components. In conclusion, our study demonstrates that BBP triggers changes in antioxidant-related indicators in rotifers; this leads to activation of related genes and subsequent changes in intracellular signaling, which in turn triggers endoplasmic reticulum stress and ultimately leads to disruption of cell function and structure. These findings highlight the potential risks associated with BBP exposure and provide fundamental insights into its toxicological effects on marine invertebrates.


Assuntos
Antioxidantes , Rotíferos , Animais , Feminino , Antioxidantes/metabolismo , Estresse Oxidativo , Retículo Endoplasmático/metabolismo , Malondialdeído/metabolismo , Superóxido Dismutase/metabolismo
6.
Int J Mol Sci ; 24(3)2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36768764

RESUMO

Exploring new and high efficiency mimic enzymes is a vital and novel strategy for antibacterial application. Haloperoxidase-like enzymes have attracted wide attention thanks to their amazing catalytic property for hypohalous acid generation from hydrogen peroxide and halides. However, few materials have displayed halogenating catalytic performance until now. Herein, we synthesized N-doped C/CeO2 (N-C/CeO2) composite materials by a combination of the liquid and solid-state method. N-C/CeO2 can possess haloperoxidase-like catalytic activity by catalyzing the bromination of organic signaling compounds (phenol red) with H2O2 at a wide range of temperatures (20 °C to 55 °C), with a solution color changing from yellow to blue. Meanwhile, it exhibits high catalytic stability/recyclability in the catalytic reaction. The synthesized N-C/CeO2 composite can effectively catalyze the oxidation of Br- with H2O2 to produce HBrO without the presence of phenol red. The produced HBrO can resist typical marine bacteria like Pseudomonas aeruginosa. This study provides an efficient biomimetic haloperoxidase and a novel sustainable method for antibacterial application.


Assuntos
Peróxido de Hidrogênio , Fenolsulfonaftaleína , Carbono , Biomimética , Oxirredução
7.
Opt Express ; 30(9): 14002-14018, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35473154

RESUMO

By using single-layer metasurfaces, we realized ultrawide-angle high-transmission in the millimeter-wave band, which allowed more than 98% transmission of dual-polarized electromagnetic waves for almost all incident angles. The multipolar expansion method was used to analyze and verify the condition of the generalized Kerker effect at the corresponding reflected angles. Using quartz glass substrates with the same metallic periodic structures, electromagnetic windows are proposed that can improve any-directed 5G millimeter-wave communication signals from outdoor to indoor environments. The proposed interpretations can connect the Kerker effect with actual applications and enable the design of easy-to-integrate all-angle Kerker effect metasurface devices.

8.
Nanotechnology ; 33(40)2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35767929

RESUMO

We propose an anti-scratch flexible surface-enhanced Raman scattering substrate with arrayed nanocavity microstructures fabricated by colloidal lithography. The nanocavity microstructure of the substrate can well protect the inner gold nanoparticles during wipe sampling. The prepared flexible substrate was able to detect 4-aminothiophenol (4-ATP) with a concentration down to 1 fM. Furthermore, the substrate was used to detect 6-BA residues on the surface of apples and bean sprouts through wipe sampling, which shows great potential in the field of rapid on-site detection, especially in the detection of pesticide residues on the surface of fruits and vegetables.


Assuntos
Nanopartículas Metálicas , Resíduos de Praguicidas , Frutas/química , Ouro/química , Nanopartículas Metálicas/química , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/química , Análise Espectral Raman , Verduras/química
9.
Can J Microbiol ; 68(6): 447-455, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35412394

RESUMO

Marine biofouling occurs through the colonization of undesired microorganisms on the surfaces of structures. In this study, four immersion cycles (2, 5, 15, and 25 days) of total immersion in seawater were carried out at the Sanya Marine Environmental Test Station using three materials: industrial pure titanium (Ti), hot-dip zinc (Zn), and glass slide (GS). Three phyla, four classes, and nine bacterial genera were identified. The dominant genera were Pseudomonas, Alteromonas, and Pseudoalteromonas. The number of bacteria increased with soaking time. Sixty-one species of diatoms belonging to 30 genera, 24 families, and 16 orders were detected, among which the dominant genera were Amphora, Nitzschia, and Navicula. Four genera of ciliates belonged to two classes, three orders, and four families, among which the dominant species were Euplotes sp. and Uronema marinum. Tubular polychaetes was the dominant metazoans. Species diversity increased over time. The highest biofilm diversity was observed on the GS surface. The diversity of biofilms on the Ti surface was higher than that on the Zn surface. This study provides basic data for marine material research, marine corrosion, and national defence construction.


Assuntos
Diatomáceas , Microbiota , Bactérias , Biofilmes , Humanos , Água do Mar/microbiologia
10.
Int J Mol Sci ; 23(10)2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35628373

RESUMO

Microbial cells secrete extracellular polymeric substances (EPS) to adhere to material surfaces, if they get in contact with solid materials such as metals. After phase equilibrium, microorganisms can adhere firmly to the metal surfaces causing metal dissolution and corrosion. Attachment and adhesion of microorganisms via EPS increase the possibility and the rate of metal corrosion. Many components of EPS are electrochemical and redox active, making them closely related to metal corrosion. Functional groups in EPS have specific adsorption ability, causing them to play a key role in biocorrosion. This review emphasizes EPS properties related to metal corrosion and protection and the underlying microbially influenced corrosion (MIC) mechanisms. Future perspectives regarding a comprehensive study of MIC mechanisms and green methodologies for corrosion protection are provided.


Assuntos
Incrustação Biológica , Matriz Extracelular de Substâncias Poliméricas , Incrustação Biológica/prevenção & controle , Corrosão , Metais/química , Oxirredução
11.
Fa Yi Xue Za Zhi ; 38(5): 650-656, 2022 Oct 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-36727182

RESUMO

The clinical symptoms and signs of methamphetamine-associated psychosis (MAP) and schizophrenia are highly similar, but the situation is completely different when MAP and schizophrenia patients need to be assessed for criminal responsibility after they comitted a harmful behavior. Therefore, the distinction between the two psychoses is very important in forensic psychiatry. At present, the identification of these two psychoses is mainly dependent on the corresponding criteria such as the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) and the Chinese Classification of Mental Disorders Version 3 (CCMD-3). It's challenging to diagnose and distinguish between the two in practical cases due to their similar clinical symptoms and the lack of effective objective indexes. Different from the limitations of single omics, integrative omics intergrates data from multiple dimensions and has been extensively studied in the field of schizophrenia and has achieved some preliminary results. In view of the correlation between MAP and schizophrenia and the potential application value of integrative omics, this paper proposes an integrative omics strategy for MAP pathogenesis and forensic identification, aiming to improve the further understanding of the relationship between the two psychoses and the corresponding pathogenesis. It also provides references for the future exploration of integrative omics in forensic precise identification and effective monitoring and early warning methods.


Assuntos
Metanfetamina , Psicoses Induzidas por Substâncias , Transtornos Psicóticos , Esquizofrenia , Humanos , Metanfetamina/efeitos adversos , Psicoses Induzidas por Substâncias/diagnóstico , Psicoses Induzidas por Substâncias/etiologia , Transtornos Psicóticos/etiologia , Transtornos Psicóticos/genética , Esquizofrenia/diagnóstico , Esquizofrenia/genética , Diagnóstico Diferencial
12.
Phys Rev Lett ; 127(4): 043901, 2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34355949

RESUMO

We report the observation of polarization singularities in momentum space of 2D photonic quasicrystal slabs. Supercell approximation and band-unfolding approach are applied to obtain approximate photonic dispersions and the far-field polarization states defined on them. We discuss the relations between the topological charges of the polarization vortex singularities at Γ points and the symmetries of photonic quasicrystal slabs. With a perspective of multipolar expansions for the supercell, we confirm that the singularities are protected by the point-group symmetry of the photonic quasicrystal slab. We further uncover that the polarization singularities of photonic quasicrystal slab correspond to quasibound states in the continuum with exceptionally high-quality factors. Polarization singularities of different topological charges are also experimentally verified. Our Letter introduces core concepts of optical singularities into quasiperiodic systems, providing new platforms for explorations merging topological and singular optics.

13.
Proc Natl Acad Sci U S A ; 115(46): 11760-11765, 2018 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-30381456

RESUMO

Extensive planting of crops genetically engineered to produce insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) has suppressed some major pests, reduced insecticide sprays, enhanced pest control by natural enemies, and increased grower profits. However, rapid evolution of resistance in pests is reducing these benefits. Better understanding of the genetic basis of resistance to Bt crops is urgently needed to monitor, delay, and counter pest resistance. We discovered that a point mutation in a previously unknown tetraspanin gene in the cotton bollworm (Helicoverpa armigera), a devastating global pest, confers dominant resistance to Cry1Ac, the sole Bt protein produced by transgenic cotton planted in China. We found the mutation using a genome-wide association study, followed by fine-scale genetic mapping and DNA sequence comparisons between resistant and susceptible strains. CRISPR/Cas9 knockout of the tetraspanin gene restored susceptibility to a resistant strain, whereas inserting the mutation conferred 125-fold resistance in a susceptible strain. DNA screening of moths captured from 23 field sites in six provinces of northern China revealed a 100-fold increase in the frequency of this mutation, from 0.001 in 2006 to 0.10 in 2016. The correspondence between the observed trajectory of the mutation and the trajectory predicted from simulation modeling shows that the dominance of the mutation accelerated adaptation. Proactive identification and tracking of the tetraspanin mutation demonstrate the potential for genomic analysis, gene editing, and molecular monitoring to improve management of resistance.


Assuntos
Resistência a Inseticidas/genética , Mariposas/genética , Tetraspaninas/genética , Animais , Animais Geneticamente Modificados/genética , Bacillus thuringiensis/genética , Proteínas de Bactérias/metabolismo , China , Evolução Molecular , Estudo de Associação Genômica Ampla , Gossypium/genética , Inseticidas/metabolismo , Larva/genética , Larva/metabolismo , Controle Biológico de Vetores , Plantas Geneticamente Modificadas/genética , Mutação Puntual/genética
14.
Fa Yi Xue Za Zhi ; 37(5): 627-631, 2021 Oct 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-35187913

RESUMO

OBJECTIVES: To explore the forensic application value of cluster of differentiation 83 (CD83) and heat shock transcription factor 5(HSF5) in identifying antemortem and postmortem skin burns. METHODS: Through reverse transcription real-time quantitative polymerase chain reaction (RT-qPCR), CD83 and HSF5 mRNA levels in the skin tissues of antemortem and postmortem burned mice and human samples were detected quantitatively. RESULTS: Compared with the control group and the postmortem burned group, the mRNA levels of CD83 and HSF5 in antemortem burned mice were higher. The high mRNA expressions of CD83 could be detected 96 h after death, and the mRNA expressions of HSF5 could be observed 72 h after death. Compared with undamaged skin, increased CD83 and HSF5 mRNA levels were detected in 11 out of 15 cases(P<0.05). CONCLUSIONS: CD83 and HSF5 can be used in forensic practice as indicators for vital reaction in antemortem burn identification.


Assuntos
Queimaduras , Lesões dos Tecidos Moles , Animais , Autopsia , Queimaduras/metabolismo , Medicina Legal , Camundongos , Mudanças Depois da Morte , Pele/lesões
15.
Opt Express ; 28(1): 40-47, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-32118939

RESUMO

The generalized Kerker effect has recently gained an explosive progress in metamaterials, from the scattering management of particle clusters to the reflection and transmission manipulation of metalattices and metasurfaces. Various optical phenomena observed can be explained by the generalized Kerker effect. Due to the same nature of electromagnetic waves, we believe that the generalized Kerker effect can also be used in the microwave field. Inspired by this, in this letter we design a kind of patch array antenna to suppress the cross-polarization by interferences of multipoles. Using different far-field radiation phase symmetries of electromagnetic multipoles for the patch, the cross-polarization can be almost cancelled while the co-polarization be kept. A pair of 8×8 U-slot patch array antennas, working in a wide band (8.8 GHz-10.4 GHz), have been designed, fabricated and measured to verify our proposal. Simulated and measured results both agree well with the theory, showing more than 20 dB gain suppression of the cross-polarization, which indicates the universality of the generalized Kerker effect in electromagnetic waves.

16.
Appl Microbiol Biotechnol ; 104(2): 515-525, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31807887

RESUMO

Marine is the harshest corrosive environment where almost all marine underwater equipment and facilities undergo corrosion caused by marine microorganisms. With the development of marine resources globally, the marine engineering and relevant infrastructures have increased exponentially. Microbiologically influenced corrosion (MIC) leads to severe safety accidents and great economic losses. The specific aggregation of corrosive microbial communities and their interactions with materials conform to a typical ecological adaptation mechanism. On the one hand, corrosive biofilms in the marine environment selectively colonize on a specific steel substrate by utilizing their complex community composition and various extracellular polymeric substances; on the other hand, the elemental composition and surface microstructure of different engineering steels affect the microbial community and corrosive process. MIC in the marine environment is a dynamic process evolving with the formation of corrosive biofilms and corrosion products. In this mini-review, the interactions between corrosive biofilm and steel substrates are explored and discussed, especially those conducted in situ in the marine environment. Herein, the important role of iron in the dynamic process of marine corrosion is highlighted.


Assuntos
Organismos Aquáticos/crescimento & desenvolvimento , Organismos Aquáticos/metabolismo , Biofilmes/crescimento & desenvolvimento , Corrosão , Ferro/metabolismo , Microbiota , Aço
17.
Pestic Biochem Physiol ; 170: 104705, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32980068

RESUMO

Magnolia officinalis, as a well-known herb worldwide, has been widely used to treat multiple diseases for a long time. In this study, the petroleum ether extract from M. officinalis showed effective antifungal activity against seven plant pathogens (particularly against R. solani with an inhibition rate of 100.00% at 250 µg/mL). Honokiol and magnolol, isolated by the bioassay-guided method, exhibited greater antifungal activity than tebuconazole (EC50 = 3.07 µg/mL, p ≤ 0.001) against R. solani, which EC50 values were 2.18 µg/mL and 3.48 µg/mL, respectively. We used transcriptomics to explore the mechanism of action of honokiol against R. solani. Results indicated that honokiol may exert antifungal effects by blocking the oxidative phosphorylation metabolic pathway. Further studies indicated that honokiol induced ROS overproduction, disrupted the mitochondrial function, affected respiration, and blocked the TCA cycle, which eventually inhibited ATP production. Besides, honokiol also damaged cell membranes and caused morphological changes. This study demonstrated that the lignans isolated from M. officinalis possess the potential to be developed as botanical fungicides.


Assuntos
Lignanas/farmacologia , Magnolia , Antifúngicos/farmacologia , Bioensaio , Compostos de Bifenilo
18.
Sensors (Basel) ; 20(18)2020 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-32899981

RESUMO

A stripline-fed tightly coupled array antenna with compact size, large scan volume and low cross-polarization characteristics is proposed for ultrawideband (UWB) applications. Simple impedance-matching process is realized by using parallel dual dipoles. Meanwhile, the parallel symmetrical radiating structures minimize the cross-polarization field components dramatically. The mitigation of various undesired resonances is studied in detail. An infinite array is designed to achieve 3:1 bandwidth (6-18 GHz) when scanning ±60∘ in the E-/D-planes (VSWR < 2.5) and H-plane (VSWR < 3.5). The cross-polarization levels remain below -29 dB at broadside. A 16 × 16 prototype is fabricated to demonstrate the design. The measured results are consistent well with the simulated ones. The overall size of the prototype at the lowest operating frequency is 3×3×0.4λ03 (15×15×2cm3). Due to its wide bandwidth, good electronic scan performance and compact size, the proposed antenna array is a good candidate for modern wireless platforms.

19.
Int Ophthalmol ; 40(10): 2495-2502, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32468429

RESUMO

PURPOSE: To investigate the risk factors associated with progressive fibrovascular proliferation (FVP) in proliferative diabetic retinopathy (PDR). METHODS: We retrospectively reviewed the clinical data of patients who underwent pars plana vitrectomy for PDR between August 2017 and October 2019 at our department of ophthalmology. The FVP was divided into five grades based on the coverage area of proliferative membrane. Then we compared the patients with different severities of FVP to analyze the risk factors for higher grade of FVP in PDR. RESULTS: Univariate analysis showed that positive urinary protein (p = 0.007), higher levels of serum blood urea nitrogen (BUN) (p < 0.001) and serum creatinine (p < 0.001), more severe stage of estimated glomerular filtration rate (p < 0.001), age < 45 years (p = 0.005), longer duration of diabetic retinopathy (p = 0.007), history of hypertension (p = 0.034) and smoking (p = 0.008) were related to FVP grade ≥ 3. Multivariate analysis showed that the level of BUN, age < 45 years and smoking were independent risk factors for FVP grade ≥ 3 in PDR patients. CONCLUSION: This study demonstrated that BUN (odds ratio [OR] = 1.318, 95% confidence interval [CI] = 1.150-1.511, p < 0.001), age ≤ 45 years (OR = 3.774, 95% CI = 1.762-8.082, p = 0.001) and smoking (OR = 2.111, 95% CI = 1.040-4.288, p = 0.039) were independent risk factors for progressive FVP in PDR among northeastern Chinese patients.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Proliferação de Células , Retinopatia Diabética/epidemiologia , Retinopatia Diabética/cirurgia , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Vitrectomia
20.
Opt Express ; 27(2): 1080-1089, 2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30696179

RESUMO

Plasmonic modes at mid-infrared wavelengths in elliptical graphene disk arrays were studied. Theoretically, analytical expressions for the modes and their dependence on the size, Fermi energy and the permittivity of substrate materials of the ellipses were derived. Experimentally, the elliptical graphene disks were fabricated and their plasmonic modes were characterized with the polarization-resolved extinction spectra. Both experimental and analytical results show that two electrical dipole modes, whose dipole moments are orthogonal to each other and along the major and minor axis of the ellipse respectively, exist in the elliptical disks. By adjusting the polarization directions of the incident light, the two orthogonal plasmonic modes could be excited either together or separately, showing that the optical properties of elliptical graphene disks are highly polarization dependent. By using ultraviolet illumination to change the Fermi energy of the elliptical graphene disks, the two modes can be tuned dynamically. Moreover, the highly polarization dependent modes are able to couple with the surface phonons of the substrate, leading to polarized plasmon-phonon polaritons. Thus the elliptical graphene disks can provide more degrees of freedom to design the mid-infrared polarization-resolved photonic devices.

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