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1.
Proc Natl Acad Sci U S A ; 119(10): e2110756119, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35235447

RESUMO

SignificanceAerosol-cloud interaction affects the cooling of Earth's climate, mostly by activation of aerosols as cloud condensation nuclei that can increase the amount of sunlight reflected back to space. But the controlling physical processes remain uncertain in current climate models. We present a lidar-based technique as a unique remote-sensing tool without thermodynamic assumptions for simultaneously profiling diurnal aerosol and water cloud properties with high resolution. Direct lateral observations of cloud properties show that the vertical structure of low-level water clouds can be far from being perfectly adiabatic. Furthermore, our analysis reveals that, instead of an increase of liquid water path (LWP) as proposed by most general circulation models, elevated aerosol loading can cause a net decrease in LWP.

2.
BMC Gastroenterol ; 23(1): 268, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37537540

RESUMO

BACKGROUND: Structural maintenance of chromosomes protein 1 A (SMC1A) is a crucial subunit of the cohesion protein complex and plays a vital role in cell cycle regulation, genomic stability maintenance, chromosome dynamics. Recent studies demonstrated that SMC1A participates in tumorigenesis. This reseach aims to explore the role and the underlying mechanisms of SMC1A in gastric cancer (GC). MATERIALS AND METHODS: RT-qPCR and western blot were used to examine the expression levels of SMC1A in GC tissues and cell lines. The role of SMC1A on GC cell proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) were analyzed. Furthermore,the mechanism of SMC1A action was investigated. RESULTS: SMC1A was highly expressed in GC tissues and cell lines. The high expression of SMC1A indicated the poor overall survival of GC patients from Kaplan-Meier Plotter. Enhancing the expression of SMC1A in AGS cells remarkably promoted cell proliferation in vitro and in vivo, migration and invasion, Conversely, knockdown of SMC1A in HGC27 cells inhibited cell proliferation, migration and invasion. Moreover, it's observed that SMC1A promoted EMT and malignant cell behaviors via regulating SNAIL. CONCLUSION: Our study revealed that SMC1A promotes EMT process by upregulating SNAIL, which contributes to gastric cancer cell proliferation, migration and invasion. Therefore, targeting SMC1A may be a potential strategy to improve GC therapy.


Assuntos
Proteínas Cromossômicas não Histona , Transição Epitelial-Mesenquimal , Neoplasias Gástricas , Humanos , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Invasividade Neoplásica , Neoplasias Gástricas/patologia , Proteínas Cromossômicas não Histona/genética
3.
Opt Lett ; 47(19): 5028-5031, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36181178

RESUMO

A novel implementation of high-spectral-resolution LIDAR based on a passively Q-switched few-longitudinal mode laser (PQFLM-HSRL) is proposed, and the prototype is built for detecting aerosol and cloud characteristics. The spatial-temporal distributions of the aerosol and cloud are continuously observed by the PQFLM-HSRL for the first time, to the best of our knowledge. Based on observation, we present the retrieval results of backscatter coefficient, particle linear depolarization ratio, and LIDAR ratio, and these intensive parameters are used to classify the aerosol and cloud into different types. Particularly, we have observed mix-phased clouds. The resulting aerosol optical depths (AODs) are highly consistent with CE-318, the Sun photometer measurements of the local National Meteorological Station (NMS), which verify the retrieval accuracy and the system stability. In addition, the retrieved AODs also characterize the ambient air quality, which show a high correlation with the measured PM2.5 concentrations. The implementation of the PQFLM-HSRL provides a new method for atmospheric feature detection, which shows superior scientific potential for further study on climate change and environmental health.

4.
Appl Opt ; 61(30): 8936-8943, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36607021

RESUMO

This article highlights the validation of the dual fields-of-view (FOVs) polarization lidar technique for the retrieval of cloud droplet effective radius in conjunction with cloud extinction coefficient of homogeneous water cloud via simulation approach. The simulation is based on polarimetric Monte Carlo method incorporated with semianalytic features under multiple-scattering conditions. The simulation results show that the depolarization ratio measured at dual-FOVs is a function of the cloud droplet effective radius and cloud extinction coefficient. Using the method of standard deviation on extensive simulation results and then by applying the polynomial regression, two polynomial relationships are obtained expressing the retrieval of the cloud droplet effective radius and cloud extinction coefficient from the layer integrated depolarization ratio at low optical depths close to the cloud bottom. Eventually, the results those presented by Ref.[1] are validated. The water cloud microphysical properties, liquid water content and cloud droplet number concentration are the functions of these two parameters and thus can be found numerically.

5.
J Insect Sci ; 22(5)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36082675

RESUMO

CRISPR/Cas9 technology is a very powerful genome editing tool and has been used in many insect species for functional genomics studies through targeted gene mutagenesis. Here, we successfully established CRISPR/Cas9 research platform in Asian multi-colored ladybird beetle, Harmonia axyridis, an important natural enemy in biological control. In this study, one pivotal gene dopa decarboxylase (DDC) in melanin synthesis was targeted by CRISPR/Cas9 to generate mutants in H. axyridis by CRISPR/Cas9 technology. Our results showed that injection of single guide RNA of the DDC and Cas9 protein into preblastoderm eggs induced one insertion and four deletion (indels) mutant H. axyridis. Mutations of HaDDC gene generated 25% mutant rate with melanin missing phenotype in larva, pupa,l and adult stage. The predation ability of the fourth instar larvae has no significant difference between wild (control) and mutant H. axyridis (G0), while these mutant fourth instar larvae had longer developmental period than that of the wild type. Consequently, the total predation of the fourth instar larvae was significantly increased in H. axyridis mutants comparing with the wild type. These results indicated that the success of CRISPR/Cas9 gene editing in H. axyridis. The gene editing platform in H. axyridis would facilitate the gene function research and promote special strain of predatory ladybird beetle generation.


Assuntos
Besouros , Animais , Sistemas CRISPR-Cas , Besouros/genética , Dopa Descarboxilase , Larva , Melaninas , Óvulo
6.
Sensors (Basel) ; 22(4)2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35214581

RESUMO

This work presents polarization property studies of water clouds using a circular polarization lidar through a simulation approach. The simulation approach is based on a polarized, semianalytic Monte Carlo method under multiple-scattering conditions and considers three types of water clouds (namely homogeneous, inhomogeneous and partially inhomogeneous). The simulation results indicate that the layer-integrated circular depolarization ratios show similar variation trends as those of layer-integrated linear depolarization ratios. The Mishchenko-Hovenier relationship is validated to correlate the simulated layer-integrated circular and linear depolarization ratios. In addition, the cloud droplet effective radius, extinction coefficient, lidar field-of-view (FOV) and height of the cloud bottom are all found to affect the layer-integrated depolarization ratio. The current work theoretically indicates that a circular polarization lidar can efficiently perform measurements of water clouds, enjoying the advantage of higher sensitivity compared to a traditional linear polarization lidar. Hence, it should be of interest to researchers in fields of polarization lidar applications.

7.
Soft Matter ; 17(13): 3654-3663, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33666629

RESUMO

In this work, through the coordination of C3 symmetric azopyridine ligands and Ag(i), coordination polymers with azo groups on the main chain were prepared. The trans coordination polymer formed an organogel with a network of nanofibers at low critical gelation concentrations, and it exhibited the abilities of self-healing and multi-stimuli response to heating, light, mechanical shearing, and chemicals due to the presence of dynamic coordinating bonds. On the other hand, the cis coordination polymer was found to assemble into nanoparticles to give a responsive colloid, which can produce fibrous precipitation in several days upon visible light irradiation due to the isomerization of the azo groups. This work provides a novel example for the design of a multi-responsive organogel and colloid based on the structural transformation of coordination polymers.

8.
Cereb Cortex ; 30(8): 4617-4632, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32219328

RESUMO

Synaptic plasticity is the neural basis of physiological processes involved in learning and memory. Tripartite motif-containing 32 (TRIM32) has been found to play many important roles in the brain such as neural stem cell proliferation, neurogenesis, inhibition of nerve proliferation, and apoptosis. TRIM32 has been linked to several nervous system diseases including autism spectrum disorder, depression, anxiety, and Alzheimer's disease. However, the role of TRIM32 in regulating the mechanism of synaptic plasticity is still unknown. Our electrophysiological studies using hippocampal slices revealed that long-term potentiation of CA1 synapses was impaired in TRIM32 deficient (KO) mice. Further research found that dendritic spines density, AMPA receptors, and synaptic plasticity-related proteins were also reduced. NMDA receptors were upregulated whereas GABA receptors were downregulated in TRIM32 deficient mice, explaining the imbalance in excitatory and inhibitory neurotransmission. This caused overexcitation leading to decreased neuronal numbers in the hippocampus and cortex. In summary, this study provides this maiden evidence on the synaptic plasticity changes of TRIM32 deficiency in the brain and proposes that TRIM32 relates the notch signaling pathway and its related mechanisms contribute to this deficit.


Assuntos
Encéfalo/fisiologia , Plasticidade Neuronal/fisiologia , Receptores Notch/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Potenciais Pós-Sinápticos Excitadores/fisiologia , Masculino , Camundongos , Camundongos Knockout , Neurônios/fisiologia
9.
Phys Rev Lett ; 124(12): 128101, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32281830

RESUMO

The discovery of magnetic protein provides a new understanding of a biocompass at the molecular level. However, the mechanism by which magnetic protein enables a biocompass is still under debate, mainly because of the absence of permanent magnetism in the magnetic protein at room temperature. Here, based on a widely accepted radical pair model of a biocompass, we propose a microscopic mechanism that allows the biocompass to operate without a finite magnetization of the magnetic protein in a biological environment. With the structure of the magnetic protein, we show that the magnetic fluctuation, rather than the permanent magnetism, of the magnetic protein can enable geomagnetic field sensing. An analysis of the quantum dynamics of our microscopic model reveals the necessary conditions for optimal sensitivity. Our work clarifies the mechanism by which magnetic protein enables a biocompass.


Assuntos
Campos Magnéticos , Modelos Teóricos , Animais , Biofísica , Aves , Proteínas Ferro-Enxofre/química , Proteínas Ferro-Enxofre/fisiologia , Navegação Espacial
10.
Phys Rev Lett ; 124(17): 170402, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32412264

RESUMO

Rare-earth related electron spins in crystalline hosts are unique material systems, as they can potentially provide a direct interface between telecom band photons and long-lived spin quantum bits. Specifically, their optically accessible electron spins in solids interacting with nuclear spins in their environment are valuable quantum memory resources. Detection of nearby individual nuclear spins, so far exclusively shown for few dilute nuclear spin bath host systems such as the nitrogen-vacancy center in diamond or the silicon vacancy in silicon carbide, remained an open challenge for rare earths in their host materials, which typically exhibit dense nuclear spin baths. Here, we present the electron spin spectroscopy of single Ce^{3+} ions in a yttrium orthosilicate host, featuring a coherence time of T_{2}=124 µs. This coherent interaction time is sufficiently long to isolate proximal ^{89}Y nuclear spins from the nuclear spin bath of ^{89}Y. Furthermore, it allows for the detection of a single nearby ^{29}Si nuclear spin, native to the host material with ∼5% abundance. This study opens the door to quantum memory applications in rare-earth ion related systems based on coupled environmental nuclear spins, potentially useful for quantum error correction schemes.

11.
Int J Mol Sci ; 21(6)2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32197465

RESUMO

Melanization is a common phenomenon in insects, and melanin synthesis is a conserved physiological process that occurs in epidermal cells. Moreover, a comprehensive understanding of the mechanisms of melanin synthesis influencing insect pigmentation are well-suited for investigating phenotype variation. The Asian multi-colored (Harlequin) ladybird beetle, Harmonia axyridis, exhibits intraspecific polymorphism based on relative levels of melanization. However, the specific characteristics of melanin synthesis in H. axyridis remains elusive. In this study, we performed gene-silencing analysis of the pivotal inverting enzyme, tyrosine hydroxylase (TH), and DOPA decarboxylase (DDC) in the tyrosine metabolism pathway to investigate the molecular and regulatory mechanism of melanin synthesis in H. axyridis. Using RNAi of TH and DDC genes in fourth instar larvae, we demonstrated that dopamine melanin was the primary contributor to the overall body melanization of H. axyridis. Furthermore, our study provides the first conclusive evidence that dopamine serves as a melanin precursor for synthesis in the early pupal stage. According to transcription factor Pannier, which is essential for the formation of melanic color on the elytra in H. axyridis, we further demonstrated that suppression of HaPnr can significantly decrease expression levels of HaTH and HaDDC. These results in their entirety lead to the conclusion that transcription factor Pannier can regulate dopamine melanin synthesis in the dorsal elytral epidermis of H. axyridis.


Assuntos
Besouros , Regulação da Expressão Gênica/fisiologia , Proteínas de Insetos , Melaninas , Animais , Besouros/genética , Besouros/metabolismo , Proteínas de Insetos/biossíntese , Proteínas de Insetos/genética , Melaninas/biossíntese , Melaninas/genética
12.
J Transl Med ; 17(1): 92, 2019 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-30885234

RESUMO

BACKGROUND: Identifying intestinal node-negative gastric adenocarcinoma (INGA) patients with high risk of recurrence could help perceive benefit of adjuvant therapy for INGA patients following surgical resection. This study evaluated whether the computer-extracted image features of nuclear shapes, texture, orientation, and tumor architecture on digital images of hematoxylin and eosin stained tissue, could help to predict recurrence in INGA patients. METHODS: A tissue microarrays cohort of 160 retrospectively INGA cases were digitally scanned, and randomly selected as training cohort (D1 = 60), validation cohort (D2 = 100 and D3 = 100, D2 and D3 are different tumor TMA spots from the same patient), accompanied with immunohistochemistry data cohort (D3' = 100, a duplicate cohort of D3) and negative controls data cohort (D5 = 100, normal adjacent tissues). After nuclear segmentation by watershed-based method, 189 local nuclear features were captured on each TMA core and the top 5 features were selected by Wilcoxon rank sum test within D1. A morphometric-based image classifier (NGAHIC) was composed across the discriminative features and predicted the recurrence in INGA on D2. The intra-tumor heterogeneity was assessed on D3. Manual nuclear atypia grading was conducted on D1 and D2 by two pathologists. The expression of HER2 and Ki67 were detected by immunohistochemistry on D3 and D3', respectively. The association between manual grading and INGA outcome was analysis. RESULTS: Independent validation results showed the NGAHIC achieved an AUC of 0.76 for recurrence prediction. NGAHIC-positive patients had poorer overall survival (P = 0.017) by univariate survival analysis. Multivariate survival analysis, controlling for T-stage, histology stage, invasion depth, demonstrated NGAHIC-positive was a reproducible prognostic factor for poorer disease-specific survival (HR = 17.24, 95% CI 3.93-75.60, P < 0.001). In contrast, human grading was only prognostic for one reader on D2. Moreover, significant correlations were observed between NGAHIC-positive patients and positivity of HER2 and Ki67 labeling index. CONCLUSIONS: The NGAHIC could provide precision oncology, personalized cancer management.


Assuntos
Forma do Núcleo Celular , Processamento de Imagem Assistida por Computador , Linfonodos/patologia , Recidiva Local de Neoplasia/patologia , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/patologia , Algoritmos , Núcleo Celular/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Reprodutibilidade dos Testes , Análise de Sobrevida
13.
Pestic Biochem Physiol ; 156: 56-62, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31027581

RESUMO

Glutamate-gated chloride channels (GluCls) mediate inhibitory synaptic transmission in invertebrate nervous systems, and only one GluCl gene has been found in insects. Therefore, insect GluCls are one of the major targets of insecticides including avermectins. In the present study, a 1347 bp full-length cDNA encoding a 449-amino acid protein (named MsGluCl, GenBank ID: MK336885) was cloned from the oriental armyworm, Mythimna separata, and characterized two alternative splicing variants of MsGluCl. The protein shares 76.9-98.6% identity with other insect GluCl isoforms. Spatial and temporal expression analysis revealed that MsGluCl was highly expressed in the 3rd instar and adult head. Dietary ingestion of dsMsGluCl significantly reduced the mRNA level of MsGluCl and decreased abamectin mortality. Thus, our results reveal that MsGluCl could be the molecular target of abamectin and provide the basis for further understanding the resistance mechanism to abamectin in arthropods.


Assuntos
Processamento Alternativo/genética , Canais de Cloreto/metabolismo , Clonagem Molecular/métodos , Mariposas/genética , Animais , Canais de Cloreto/genética , DNA Complementar/genética , DNA Complementar/metabolismo , Inseticidas/farmacologia , Ivermectina/análogos & derivados , Ivermectina/farmacologia , Mariposas/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
14.
J Cell Physiol ; 234(1): 619-631, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-30069972

RESUMO

Pancreatic cancer (PC) is a serious malignancy with high mortality and poor prognosis due to nonspecific incipient symptoms and early metastasis. Also, increasing evidence indicates that a panel of genes is newly identified in the pathogenesis of PC. As is a regulatory subunit, elevated cyclin B1 (CCNB1) expression has been detected in different cancers including PC. This study is designed to investigate the effects of CCNB1 silencing on cell cycle, senescence, and apoptosis through the p53 signaling pathway in PC. PC tissues and normal pancreatic tissues were collected. Cells were transfected and assigned into different groups. The expressions of CCNB1, p53, MDM2, Bax, caspase-9, caspase-3, and p21 in tissues and cells were detected by reverse transcription quantitative polymerase chain reaction and western blot analysis. ß-Galactosidase staining, MTT assay, and flow cytometry were conducted to test cell senescence, proliferation, cell cycle, and apoptosis. PC tissues showed higher expressions of CCNB1 and MDM2 and lower expressions of Bax, caspase-9, caspase-3, and p21. Cells transfected with shCCNB1 had lower expressions of CCNB1 and MDM2, whereas higher expressions of Bax, caspase-9, caspase-3, p53, and p21. The shCCNB1 group had decreased proliferation and S-phase cell proportion and increased apoptosis, senescence, and G0/G1-phase cell proportion. The PFT-α group showed higher expressions of MDM2 and lower expressions of Bax, caspase-9, caspase-3, p53, and p21. The PFT-α group had increased proliferation and S-phase cell proportion and declined apoptosis, senescence, and G0/G1-phase cell proportion. CCNB1 silencing inhibits cell proliferation and promotes cell senescence via activation of the p53 signaling pathway in PC.


Assuntos
Apoptose/genética , Ciclina B1/genética , Neoplasias Pancreáticas/genética , Proteína Supressora de Tumor p53/genética , Idoso , Envelhecimento/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Ciclina B1/antagonistas & inibidores , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Neoplasias Pancreáticas/patologia , Transdução de Sinais/genética , Transfecção
15.
Soft Matter ; 14(43): 8764-8770, 2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30328881

RESUMO

In this study, a novel self-assembled metal-organic gel was synthesized from ferric nitrate and a di-topic ligand, bis(3-pyridyl)terephthalate. The gel consisted of a three dimensional network of uniform nanofibers. The gelation exhibited high selectivity to Fe(iii) based on metal-ligand coordination. The molar ratio of Fe3+ to ligand had a large influence on the assembly process and the morphology of the gel. The metallogel displayed multi-stimuli responsiveness and excellent heat resistance, thus was further applied as a thermo-stable template for the polymerization of N,N'-methylene bisacrylamide to produce the core/shell polymer composite nanowires. Subsequently, the polymer nanotubes were obtained after ammonia post-treatment, comfirming the feasibility of the template synthesis strategy. According to the rheological measurements, the gel-like products of the composite nanowires exhibited better mechanical strength compared to the gel template.

16.
Pestic Biochem Physiol ; 145: 1-7, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29482724

RESUMO

The Bemisia tabaci (Gennadius) cryptic species complex comprises very destructive insect pests of agricultural crops worldwide and has been found to be resistant to various insecticides in China. Abamectin is one of the most widely used insecticides for insect pest control and the glutamate-gated chloride channel (GluCl) in insects was presumed to be the main target site of abamectin. In this study, a 1353bp full-length cDNA encoding GluCl (named BtGluCl, GenBank ID: MF673854) was cloned and characterized from B. tabaci. BtGluCl encodes 450 amino acids, which shares 71-81% identity with other insect GluCl isoforms. Spatial and temporal expression revealed BtGluCl was highly expressed in the 4th nymphal instar and adult head, and the least expressed in the 1st nymphal instar and adult leg. Dietary ingestion of dsBtGluCl significantly reduced the mRNA level of BtGluCl in the treated adults by 62.9% and greatly decreased abamectin-induced mortality. Thus, our results could be conducive to further understanding the mechanisms of resistance to abamectin in arthropods.


Assuntos
Canais de Cloreto/genética , Hemípteros/efeitos dos fármacos , Inseticidas/farmacologia , Ivermectina/análogos & derivados , Interferência de RNA , Processamento Alternativo , Sequência de Aminoácidos , Aminoácidos/análise , Animais , Canais de Cloreto/química , Clonagem Molecular , DNA Complementar/genética , Dieta , Resistência a Medicamentos , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Hemípteros/genética , Ivermectina/farmacologia , Filogenia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos
17.
Pestic Biochem Physiol ; 148: 34-41, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29891375

RESUMO

The ryanodine receptors of insects are the main target sites of diamide insecticides, which show highly selective insecticidal activity relative to toxicity in mammals and provide a novel option for managing lepidopteran pests. The oriental armyworm, Mythimna separata (Walker), is a destructive pest of agricultural crops, and great efforts have been undertaken to control this pest including repeated insecticide applications. In this study, full-length cDNA of a ryanodine receptor gene from M. separata (MsRyR) was cloned and characterized. The cDNA of MsRyR had a 15,372 bp open reading frame and encoded 5124 amino acids (GenBank ID: MG712298). MsRyR shares 78-97% identity with RyR isoforms of other insects, and <50% identities with Homo sapiens RyRs 1-3. Temporal and spatial expression analysis detected MsRyR at all developmental stages and in all tissues. The highest relative levels of MsRyR were detected in the second instar and head. Exposure to chlorantraniliprole after 24 h significantly increased the expression levels of whole body MsRyR mRNA. In addition, dietary ingestion of dsMsRyR significantly reduced the mRNA level of MsRyR and greatly decreased chlorantraniliprole-induced mortality. Our results revealed that the MsRyR could be the molecular target of chlorantraniliprole, and provided the basis for further understanding the resistance mechanism of chlorantraniliprole.


Assuntos
Inativação Gênica , Genes de Insetos , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Lepidópteros/efeitos dos fármacos , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , ortoaminobenzoatos/farmacologia , Sequência de Aminoácidos , Animais , Clonagem Molecular , Produtos Agrícolas , DNA Complementar , Perfilação da Expressão Gênica , Lepidópteros/genética , Lepidópteros/crescimento & desenvolvimento , Fases de Leitura Aberta , Filogenia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos
18.
J Asian Nat Prod Res ; 20(2): 128-138, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28492090

RESUMO

Camellia oleifera is expected to provide alternative aglycone to synthesize some saponins similar to that from Schima superba with inhibitory activity against Magnaporthe oryzae. Eight theasapogenol galactosides were synthesized via protection of adjacent hydroxyl groups by a benzylidene for regioselective glycosylation in the multi-hydroxyl sapogenin. Water soluble galactose chain connected far from liposoluble end was a key group in inhibiting the growth of M. oryzea unless theasapogenol was modified by two galactosyl groups or by one galactosyl group and one benzylidene group. The amphoteric characteristics of saponin such as saccharide group number, distance between bipolar groups play an important role in inhibiting mycelium growth of M. oryzae.


Assuntos
Galactosídeos/isolamento & purificação , Galactosídeos/farmacologia , Magnaporthe/efeitos dos fármacos , Saponinas/síntese química , Theaceae/química , Camellia/química , Galactosídeos/química , Estrutura Molecular , Saponinas/química , Relação Estrutura-Atividade
19.
Ecotoxicology ; 26(7): 1002-1009, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28685415

RESUMO

Beta-cypermethrin has long been recommended as an effective pesticide to control the soybean aphid, Aphis glycines Matsumura, a serious pest in soybean crops. Besides acute toxicity, it leads to changes in life history traits of A. glycines, notably its reproductive potential. This study has assessed the effects of five sublethal concentrations (0.625, 1.25, 2.5, 5 and 10 µg/L) of beta-cypermethrin on different life history traits of A. glycines. Exposure to these concentrations caused shorter oviposition period and reduced adult longevity. The strongest stimulatory effect on aphid reproduction was achieved when exposed to a higher sublethal beta-cypermethrin concentration (5 µg/L). Net reproduction rate (R 0 ), intrinsic rate of increase (r m ) and finite rate of increase (λ) were significantly higher than that of the control, increasing by 20.58, 4.89 and 2.06%, respectively. We found no significant difference in mean generation time (T) between the treatment of 5 µg/L beta-cypermethrin and the control. However, when the concentration increased to 10 µg/L, the reproduction behavior was restrained and the mean generation time (T) was shortened, resulting in significant decrease in R 0 and T by 16.58 and 3.83%, respectively. In conclusion, a sublethal concentration (5 µg/L) of beta-cypermethrin triggered the strongest hormesis on A.glycines, thus providing valuable knowledge on the sublethal effects of this insecticide on soybean aphids. Hormesis may be one of the mechanisms underlying pest resurgences, and better knowledge would enable a more effective use of insecticides in Integrated Pest Management programs.


Assuntos
Afídeos/fisiologia , Inseticidas/toxicidade , Piretrinas/toxicidade , Testes de Toxicidade , Animais , Afídeos/efeitos dos fármacos , Hormese/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Glycine max
20.
Chem Pharm Bull (Tokyo) ; 65(2): 178-185, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28154310

RESUMO

Fatty acid synthesis (FAS) is an essential metabolism during the whole growth and development process of the bacterial. Several key enzymes which involved in this biosynthetic pathway have been considered as useful targets for the development of new antibacterial agents. Among them, ß-ketoacyl-acyl carrier protein synthase III (FabH) is the most magnetic target, since it is central to the initiation of fatty acid biosynthesis and is highly conserved of both Gram-positive and Gram-negative bacteria. Following the previous researches, Schiff-based derivatives with dioxygenated rings and N-heterocycle were synthesized in succession, and their biological activities as potential FabH inhibitors were evaluated in this paper. Among these 15 compounds, compound 2E exhibited the best antibacterial activities with minimum inhibitory concentration (MIC) values 1.56-3.13 mg/mL against the tested bacterial strains and showed the most powerful Escherichia coli (E. coli) FabH inhibitory activities with IC50 of 2.1 µM. Also the conceivable binding conformation of placing compound 2E into the E. coli FabH active site was affirmed docking simulation.


Assuntos
3-Oxoacil-(Proteína de Transporte de Acila) Sintase/antagonistas & inibidores , Antibacterianos/química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Compostos Heterocíclicos/química , Compostos de Nitrogênio/química , Bases de Schiff/química , Antibacterianos/farmacologia , Compostos Heterocíclicos/farmacologia , Testes de Sensibilidade Microbiana , Compostos de Nitrogênio/farmacologia , Bases de Schiff/farmacologia , Relação Estrutura-Atividade
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