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1.
Mol Nutr Food Res ; 68(1): e2300165, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37891713

RESUMO

SCOPE: The study aims to investigate the role of the sulfur microbial diet in the survival of ovarian cancer (OC). METHODS AND RESULTS: A prospective cohort study is conducted with 703 patients diagnosed with OC between 2015 and 2020. Diet information is collected using a validated food frequency questionnaire. Deaths are ascertained up to March 31, 2021, via the death registry linkage. During the follow-up period (median: 37.2 months, interquartile range: 24.7-50.2 months), 130 deaths are observed. A higher sulfur microbial diet score is significantly associated with an increased risk of all-cause mortality among OC patients (tertile 3 vs tertile 1: HR = 1.93, 95% CI = 1.11-3.35). Each 1-standard deviation increment in the sulfur microbial diet score increases the all-cause mortality risk by 33% (95% CI = 1.04-1.71). Stratified analysis shows that significant associations are found in OC patients diagnosed over 50 years of age, with body mass index ≥24  kg m-2 , who changed their diet after diagnosis, or without residual lesions. CONCLUSIONS: Adherence to the sulfur microbial diet, characterized by high intakes of red meats and processed meats, and low intakes of fruits, vegetables, and whole grains, is associated with poor survival in OC patients.


Assuntos
Dieta , Neoplasias Ovarianas , Humanos , Feminino , Pessoa de Meia-Idade , Estudos Prospectivos , Verduras , Neoplasias Ovarianas/diagnóstico , Enxofre
2.
Cryobiology ; 113: 104563, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37532122

RESUMO

Acute extreme cold exposure impairs human health and even causes hypothermia which threatens human life. Liver, as a hub in metabolism and thermogenesis, is vital for cold acclimatization. Although accumulating evidence has suggested that cold exposure can cause liver damage, the underlying mechanisms remain poorly understood. This study investigated the role and underlying mechanisms of ferroptosis in cold stress-induced liver damage. To evaluate the role of ferroptosis in cold stress-induced liver damage, rats were pretreated with ferroptosis inhibitor liproxstatin-1 (Lip-1) before exposed to -10 °C for 8 h. Core body temperature was recorded. The levels of ferroptosis-related indicators were examined with the corresponding assay kits or by western blotting. Hepatic pathological changes were analyzed by hematoxylin-eosin staining and ultrastructural observation. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were measured to assess liver function. Rats were also pretreated with p38 mitogen-activated protein kinase (MAPK) inhibitor SB203580 or Dynamin-related protein 1 (Drp1) inhibitor Mdivi-1 to determine the underlying mechanisms. We found that Lip-1 inhibited ferroptosis, attenuated hepatic pathological damages and blocked the increased ALT and AST levels in cold-exposed rats. Moreover, Mdivi-1 inhibited mitochondrial fission and suppressed ferroptosis. Furthermore, SB203580 and Mdivi-1 administration alleviated cold stress-induced liver injury. Our results suggested that cold stress caused liver damage partially by inducing ferroptosis through the p38 MAPK/Drp1 pathway. These findings might provide an effective preventive and therapeutic target for cold stress-induced liver injury.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Ferroptose , Ratos , Humanos , Animais , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Resposta ao Choque Frio , Doença Hepática Crônica Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Crônica Induzida por Substâncias e Drogas/patologia , Criopreservação/métodos , Dinaminas/genética , Dinaminas/metabolismo , Fígado/metabolismo
3.
Int J Mol Sci ; 24(11)2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37298608

RESUMO

The heavy metal zinc (Zn) is known to be transmitted in the food chain; however, the effect of Zn stress on beans and herbivorous insects is largely unclear. This study aimed to investigate the resistance of broad bean plants to Zn stress and the consequent changes in their physiological and biochemical metabolism by simulating heavy metal pollution in soil. Simultaneously, the effects of aphid progeny treated with different Zn concentrations on the expression of carbohydrate and related genes were analyzed. The results showed that Zn had no effect on the germination rate of broad beans, but other effects mainly manifested as follows. (1) Chlorophyll content decreased. (2) The total soluble sugar and Zn content in stems and leaves increased with increasing Zn content. (3) The proline content first increased and then decreased with increasing Zn content. (4) The height of the seedlings indicates that low concentrations promote growth and high concentrations inhibit growth. In addition, only the first-generation fecundity decreased significantly when aphids fed on heavy metal broad beans. Continuous high Zn levels increase the trehalose content of aphid F1 and F2, while F3 decreases. These results can not only provide a theoretical basis for exploring the impact of soil heavy metal pollution on ecosystems but also preliminarily evaluate the possibility of broad beans as a means of pollution remediation.


Assuntos
Afídeos , Metais Pesados , Poluentes do Solo , Vicia faba , Animais , Zinco/metabolismo , Afídeos/fisiologia , Ecossistema , Metais Pesados/toxicidade , Reprodução , Solo/química , Poluentes do Solo/toxicidade
4.
Plants (Basel) ; 12(5)2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36903850

RESUMO

Silicon occupies an important position in the nutrient requirements of wheat. It has been reported that silicon enhances plant resistance to phytophagous insects. However, only limited research has been carried out on the effects of silicon application to wheat and Sitobion avenae populations. In this study, three silicon fertilizer concentrations were treated for potted wheat seedlings, including 0 g/L, 1 g/L, and 2 g/L of water-soluble silicon fertilizer solution. The effect of silicon application on the developmental period, longevity, reproduction, wing pattern differentiation, and other vital life table parameters of the S. avenae were determined. The cage method and the Petri dish isolated leaf method were used to determine the effect of silicon application on the feeding preference of the winged and wingless aphid. The results showed silicon application had no significant effect on the aphid instar of 1-4; although, 2 g/L silicon fertilizer prolonged the nymph stage and 1 and 2 g/L of silicon application all shortened the adult stage and reduced the longevity and fertility of the aphid. Two instances of silicon application reduced the net reproductive rate (R0), intrinsic rate of increase (rm), and finite rate of increase (λ) of the aphid. A 2 g/L silicon application prolonged the population doubling time (td), significantly reduced the mean generation time (T), and increased the proportion of winged aphids. The results also demonstrated that the selection ratio of winged aphids in wheat leaves treated with 1 g/L and 2 g/L silicon was reduced by 8.61% and 17.88%, respectively. The number of aphids on leaves treated with 2 g/L silicon was significantly reduced at 48 and 72 h of aphids released, and the application of silicon to wheat was detrimental to the feeding preference of S. avenae. Therefore, the application of silicon at 2 g/L to wheat has an inhibitory effect on the life parameters and feeding preference of S. avenae.

5.
Front Nutr ; 9: 859143, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35479758

RESUMO

Objective: We aimed to examine associations of diet quality scores, including the dietary approaches to stop hypertension (DASH), alternate Healthy Eating Index (AHEI), and Chinese Healthy Eating Index (CHEI) with asthenoteratozoospermia risk in China. Methods: Among 254 cases and 633 controls in a hospital-based case-control study in Shenyang, Liaoning Province, China, DASH, AHEI, and CHEI were calculated using a validated food frequency questionnaire. Asthenotetrazoospermia was evaluated according to World Health Organization guidelines. Unconditional multiple logistic regression was used to estimate odds ratios (ORs) with 95% confidence intervals (CIs) for the association between quality diet scores and asthenoteratozoospermia risk. Results: We found that the CHEI score was inversely associated with asthenoteratozoospermia risk, with ORs of 0.59 (95% CI 0.39, 0.88) and 0.59 (95% CI 0.39, 0.88) for the 2nd and 3rd tertiles vs. the 1st tertile, respectively (P trend < 0.05). In addition, our data indicated that each standard deviation increase in CHEI, AHEI-2010, and DASH score was associated with 19, 13, and 17% decreased risk of asthenoteratozoospermia, respectively. Conclusion: Our findings suggest that higher adherence to the CHEI, AHEI-2010, and DASH diet quality scores may reduce the risk of asthenoteratozoospermia, especially for younger participants.

6.
J Econ Entomol ; 115(2): 539-544, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35064268

RESUMO

Interspecies competition affects the distribution, quantity, and community structure of insects, especially among closely-related (congeners) species. Some ecological factors differentially affect the fitness of co-existing species, thus conferring an advantage on one competitor, and then the structure of communities. The present work evaluated the effects of high temperature and natural enemies on the interspecific competition between the grain aphid Sitobion miscanthi (Takahashi) (Aphididae: Hemiptera) and bird cherry-oat aphid Rhopalosiphum padi (L.) (Hemiptera: Aphididae), two key pests of wheat in China. Results showed that the population growth of R. padi was faster at 30°C, and the intrinsic rate of natural increase (rm) value was 5 times that of S. miscanthi, indicating that R. padi was more high-temperature resistant and has advantages in interspecific competition at high temperature. Moreover, compared to S. miscanthi, the population of R. padi was less affected by their predator, larvae of the multicolored Asian lady beetle, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), and aphid parasitoids, Aphidius avenae (Haliday) or Aphidius gifuensis (Ashmead) (Hymenoptera: Aphidiidae), which made them gain an advantage in the interspecific competition. Our results enrich the knowledge of phytophagous insect interspecific completion and implicate the ecological mechanism of R. padi may become the dominant species in wheat fields in China.


Assuntos
Afídeos , Himenópteros , Animais , China , Humanos , Temperatura
7.
Opt Express ; 29(10): 15434-15442, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33985243

RESUMO

In this paper, we propose a four-wave mixing-based photonic crystal fiber (PCF) microfluid sensor, and two U-shape microslits fabricated by a femtosecond laser are embedded into the sensor for real-time microfluid measurement. Theoretical and experimental results prove that the signal wavelength is sensitive to both the refractive index (RI) and the material dispersion property of the liquid sample filled into the air channels. For different aqueous target samples at low concentrations, the responses of signal wavelength are consistent with each other. The obtained RI sensitivity is approximately 881.36 nm/RIU, and the sensing resolution is around 1.6 × 10-4 RIU. The proposed sensor also shows a better figure of merit (FOM) as high as 313.65 RIU-1 when compared with the fiber SPR sensors. Besides, the signal wavelengths present different responses with the increasing aqueous concentration due to the separated dispersion characteristics of the filled liquid samples, which can be potentially applied for the discrimination of liquid samples with a well-designed wavelength-coded sensor array in the future.

8.
Bull Entomol Res ; 111(4): 485-498, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33745467

RESUMO

The oriental armyworm, Mythimna separata (Walker) is a serious pest of agriculture that does particular damage to Gramineae crops in Asia, Europe, and Oceania. Metamorphosis is a key developmental stage in insects, although the genes underlying the metamorphic transition in M. separata remain largely unknown. Here, we sequenced the transcriptomes of five stages; mature larvae (ML), wandering (W), and pupation (1, 5, and 10 days after pupation, designated P1, P5, and P10) to identify transition-associated genes. Four libraries were generated, with 22,884, 23,534, 26,643, and 33,238 differentially expressed genes (DEGs) for the ML-vs-W, W-vs-P1, P1-vs-P5, and P5-vs-P10, respectively. Gene ontology enrichment analysis of DEGs showed that genes regulating the biosynthesis of the membrane and integral components of the membrane, which includes the cuticular protein (CP), 20-hydroxyecdysone (20E), and juvenile hormone (JH) biosynthesis, were enriched. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated that DEGs were enriched in the metabolic pathways. Of these DEGs, thirty CP, seventeen 20E, and seven JH genes were differentially expressed across the developmental stages. For transcriptome validation, ten CP, 20E, and JH-related genes were selected and verified by real-time PCR quantitative. Collectively, our results provided a basis for further studies of the molecular mechanism of metamorphosis in M. separata.


Assuntos
Genes de Insetos , Metamorfose Biológica/genética , Mariposas/fisiologia , Transcriptoma , Animais , Ecdisterona/biossíntese , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Hormônios Juvenis/biossíntese , Larva/metabolismo , Pupa/metabolismo
9.
J Mater Chem B ; 9(11): 2584-2593, 2021 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-33666209

RESUMO

As a multifunctional platform, cyclodextrin capped gold nanoparticles (AuNP@CDs) have attracted extensive attention due to their advantages of high specific surface area and high loading capacity. AuNP@CDs have a core-shell structure, retaining the advantages of the two materials. AuNPs act as the support for the monolayer assembly of CDs. Some functional molecules can enter the hydrophobic cavity of CD through the host-guest interaction. In this brief review, we discuss the strategies for the synthesis of AuNP@CDs depending on the type and order of bonding. Their applications in drug delivery, catalysis, detection and bioimaging are highlighted. We hope to further stimulate AuNP@CD related research.


Assuntos
Ciclodextrinas/química , Ouro/química , Nanopartículas Metálicas/química , Sistemas de Liberação de Medicamentos , Estrutura Molecular
10.
Pest Manag Sci ; 77(4): 1936-1944, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33300163

RESUMO

BACKGROUND: Bacterial symbionts in insects, especially aphids, have a major influence on host adaptation. We previously showed that infection with the secondary symbiont Hamiltonella defensa increases the fitness of the wheat aphid Sitobion miscanthi, yielding increases in fitness parameters such as adult weight and offspring number. However, whether H. defensa affects the sensitivity of host aphids to insecticides remains unknown. RESULTS: We tested the effects of H. defensa on host aphid susceptibility to the insecticides chlorpyrifos methyl, imidacloprid, cyantraniliprole and acetamiprid. Our results showed that compared with Hamiltonella-free aphid clones, Hamiltonella-infected aphid clones exhibited lower sensitivity to most of the tested insecticides at low concentrations. Quantitative polymerase chain reaction showed that the density of H. defensa in the infected clones was slightly decreased at 24 h but then sharply increased until the late stage after treatment with the different insecticides. H. defensa in the host aphids was detected by fluorescence in situ hybridization and was localized to the aphid hindgut. Levels of the detoxification enzymes acetylcholinesterase, glutathione transferase and carboxylesterase were significantly higher in Hamiltonella-infected clones than in Hamiltonella-free clones. CONCLUSIONS: The findings indicated that infection with H. defensa reduced aphid susceptibility to the investigated insecticides at low concentrations, potentially by increasing detoxification enzyme activity in the host. Therefore, symbiont-mediated insecticide resistance should be taken into account when performing resistance-monitoring studies. Studies of symbiont-mediated insecticide resistance may enhance our understanding of the emergence of insecticide resistance in agricultural systems. © 2020 Society of Chemical Industry.


Assuntos
Afídeos , Inseticidas , Animais , Afídeos/genética , Enterobacteriaceae/genética , Hibridização in Situ Fluorescente , Inseticidas/farmacologia , Simbiose
11.
Ecol Evol ; 10(18): 9647-9662, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33005337

RESUMO

Genetic diversity of populations has important ecological and evolutionary consequences, whose understanding is fundamental to improve the sustainability of agricultural production. Studies of how differences in agricultural management and environment influence the population structure of insect pests are central to predict outbreaks and optimize control programs. Here, we have studied the population genetic diversity and evolution of Sitobion avenae and Sitobion miscanthi, which are among the most relevant aphid pests of cereals across Europe and Asia, respectively. We have used genotyping by sequencing (GBS) to identify genome-wide single nucleotide polymorphisms (SNPs) to infer the geographic structure and migration patterns. In the present study, we show that the population structure in present-day populations is different from that described in previous studies, which suggest that they have evolved recently possibly as a response to human-induced changes in agriculture. This study shows that S. avenae in England is predominantly parthenogenetic and there has been a demographic and spatial expansion of a single genetic cluster, which could correspond with the insecticide resistance superclone identified in previous studies. Conversely, in China, S. miscanthi populations are mostly cyclical parthenogenetic, with one sexual stage in autumn to produce overwintering eggs, and there are six genetically differentiated subpopulations and high genetic differentiation between geographic locations, which suggests that further taxonomical research is needed. Unlike S. avenae in England, there is no evidence for insecticide resistance and there is no predominance of a single lineage in S. miscanthi in China.

12.
Pest Manag Sci ; 76(3): 1039-1047, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31515930

RESUMO

BACKGROUND: Recent work has shown that two codling moth (Cydia pomonella) glutathione S-transferase genes (GSTs), CpGSTd1 and CpGSTd3, can metabolize λ-cyhalothrin, one of the recommended insecticides for C. pomonella control worldwide. However, systematical characterization of delta and epsilon GSTs, especially their potential contributions in the metabolism of λ-cyhalothrin, is currently still lacking in C. pomonella. RESULTS: In this study, a total of nine cDNA sequences were identified in C. pomonella, including four in the delta and five in the epsilon subclasses. RT-qPCR showed that seven GSTs were ubiquitously expressed at all developmental stages, and CpGSTe2, CpGSTe3, and CpGSTe4 were mainly expressed in larvae. The mRNA levels of CpGSTd2, CpGSTd4, and CpGSTe5 were significantly higher in male than in female adults. Tissue-specific expression analysis revealed that the CpGSTe2, CpGSTe3, and CpGSTe4 were highly expressed in the midgut while CpGSTd2 and CpGSTd4 were predominantly expressed in the Malpighian tubules. The transcripts of these GSTs (except CpGSTe1) were co-expressed following exposure to LD10 of λ-cyhalothrin for 3 h. Recombinant CpGSTd4, CpGSTe2, and CpGSTe3 proteins expressed in Escherichia coli displayed glutathione-conjugating activity toward 1-chloro-2,4-dinitrobenzene. In addition, λ-cyhalothrin could inhibit the activity of recombinant CpGSTd4, CpGSTe2, and CpGSTe3 enzymes, but only recombinant CpGSTe3 showed λ-cyhalothrin metabolic capacity, with 21.88 ± 1.09% of parental compound being depleted within 1 h. CONCLUSION: These data show that CpGSTe3 is a third GST gene, encoding an enzyme that metabolizes λ-cyhalothrin in C. pomonella. © 2019 Society of Chemical Industry.


Assuntos
Mariposas , Animais , Feminino , Glutationa Transferase , Masculino , Nitrilas , Piretrinas
13.
Pest Manag Sci ; 75(12): 3252-3259, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30993856

RESUMO

BACKGROUND: Climate warming has considerable effects on crop development and pest population dynamics. Crucially, the tri-trophic responses of plants, herbivores and their natural enemies to warming are poorly understood. To delineate these interactive properties, a three-system approach and integrating life table methodology were used to examine the responses of wheat plants, English grain aphid and parasitoids under open-field infrared heating to simulate warming. RESULTS: Warming significantly increased wheat biomass and grain weight, causing a phenological shift in plant growth. Importantly, warming significantly increased the number of aphids and the reproductive period, coupled with a higher net reproductive rate and intrinsic growth rate. Otherwise, duration of development, generation span, and population doubling time all decreased significantly. Warming had no effect on parasitoid abundance but resulted in a significant decrease in the rate of parasitism. CONCLUSION: Warming may strengthen bottom-up effects on aphids by increasing wheat biomass, resulting in reduced regulation of aphid populations. Warming had a different effect on parasitoids between 2015 and 2016. These findings provide an important characterization of ecological mechanisms in plant-herbivore-parasitoid systems and give a theoretical foundation for improved forecasting of aphid population dynamics under climate change. © 2019 Society of Chemical Industry.


Assuntos
Afídeos/fisiologia , Mudança Climática , Cadeia Alimentar , Temperatura Alta , Triticum/crescimento & desenvolvimento , Vespas/fisiologia , Animais , Afídeos/parasitologia , Interações Hospedeiro-Parasita , Dinâmica Populacional
14.
Pestic Biochem Physiol ; 153: 47-54, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30744896

RESUMO

Lambda-cyhalothrin has long been recommended as an effective insecticide to control the oriental armyworm, Mythimna separata (Walker), a notorious migratory pest of agricultural plants. Previous researches have suggested that survival, development, and reproduction of insects are influenced by sublethal concentrations of insecticides. However, the effects of sublethal concentrations of lambda-cyhalothrin on M. separata are less known. In this study, we determined the toxicity and effects of LC20 and LC50 concentration of lambda-cyhalothrin on development and reproduction of M. separata. Results indicate that LC20 of lambda-cyhalothrin tends to decrease the life traits of M. separate, with a shortening larvae period of offspring and oviposition period, whereas LC50 of lambda-cyhalothrin stimulates daily maximal fecundity and forwards the oviposition peak, suggesting a stimulation of reproduction by LC50 of lambda-cyhalothrin. The M. separata population was increased by an LC50 concentration of lambda-cyhalothrin, resulting in a net reproductive rate (R0) and intrinsic rate of increase (rm) significantly higher than that of the control. Transcripts of vitellogenin (MsVg) and vitellogenin receptor (MsVgR) genes were suppressed at day 1 after emergence of moth which developed from the larvae exposed to LC20 and LC50 of lambda-cyhalothrin, but were significant induced when the moth begin to lay eggs (day 4), with a more remarkable induction by LC50 of lambda-cyhalothrin than those of LC20 of lambda-cyhalothrin. Our results indicate that the observed stimulation of reproduction is therefore the results of up-regulation of MsVg and MsVgR by LC50 of lambda-cyhalothrin.


Assuntos
Proteínas do Ovo/genética , Proteínas de Insetos/genética , Inseticidas/farmacologia , Mariposas/efeitos dos fármacos , Nitrilas/farmacologia , Piretrinas/farmacologia , Receptores de Superfície Celular/genética , Vitelogeninas/genética , Animais , Feminino , Larva/efeitos dos fármacos , Larva/fisiologia , Dose Letal Mediana , Masculino , Mariposas/fisiologia , Reprodução/efeitos dos fármacos , Regulação para Cima
15.
Front Plant Sci ; 9: 778, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29967627

RESUMO

In natural ecological systems, plants are often simultaneously attacked by both insects and pathogens, which can affect each other's performance and the interactions can be extended to higher trophic levels, such as parasitoids. The English grain aphid (Sitobion avenae) and powdery mildew (Blumeria graminis f. sp. tritici) are two common antagonists that pose a serious threat to wheat production. Numerous studies have investigated the effect of a single factor (insect or pathogen) on wheat production. However, investigation on the interactions among insect pests, pathogens, and parasitoids within the wheat crop system are rare. Furthermore, the influence of the fungicide, propiconazole, has been found to imitate the natural ecosystem. Therefore, this study investigated the effects of B. graminis on the biological performance of grain aphids and the orientation behavior of its endoparasitic wasp Aphidius gifuensis in the wheat system. Our findings indicated that B. graminis infection suppressed the feeding behavior, adult and nymph weight, and fecundity and prolonged the developmental time of S. avenae. We found that wheat host plants had decreased proportions of essential amino acids and higher content of sucrose following aggravated B. graminis infection. The contents of Pro and Gln increased in the wheat plant tissues after B. graminis infection. In addition, B. graminis infection elicited immune responses in wheat: increase in the expression of defense genes, content of total phenolic compounds, and activity of three related antioxidant enzymes. Moreover, co-infection of B. graminis and S. avenae increased the attraction to A. gifuensis compare to that after infestation with aphids alone. In conclusion, our results indicated that B. graminis infection adversely affected the performance of S. avenae in wheat through restricted nutrition and induced defense response. Furthermore, the preference of parasitoids in such an interactive environment might provide an important basis for pest management control.

16.
Sensors (Basel) ; 18(6)2018 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-29843365

RESUMO

In this paper, a simplified hollow-core photonic crystal fiber surface-enhanced Raman scattering (SERS) probe is presented. Silver nanoprisms are grown with a photoreduction method and account for the SERS, which have better electromagnetic enhancement than spherical silver nanoparticles at 785 nm. Due to the antiresonant reflecting guidance mechanism, the excited laser and SERS signal are effectively guided in such a fully filled hollow-core photonic crystal fiber SERS probe and complicated selective filling with target sample is avoided. Rhodamine 6G molecules are used as probe molecules and the simplified hollow-core photonic crystal fiber SERS probe is test. Detection of low concentration Rhodamine 6G down to 10-8 M is achieved with a short integration time of 300 ms.

17.
Front Physiol ; 8: 976, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29234290

RESUMO

Aphidius gifuensis is one of the most important aphid natural enemies and has been successfully used to control Myzys persicae and other aphid species. High temperature in summer is one of the key barriers for the application of A. gifuensis in the field and greenhouse. In this work, we investigated the biological performance of A. gifuensis and the response of heat-shock proteins and antioxidant enzymes under high temperature. The results showed that A. gifuensis could not survive at 40°C and female exhibited a higher survival in 35°C. Furthermore, the short term exposure to high temperature negatively affected the performance of A. gifuensis especially parasitism efficiency. Under short-term heating, the expression of AgifsHSP, Agifl(2)efl, AgifHSP70, AgifHSP70-4 and AgifHSP90 showed an increased trend, whereas AgifHSP10 initially increased and then decreased. In 35°C, the expressions of Agifl(2)efl, AgifHSP70-4 and AgifHSP90 in female were higher than those in male, whereas the expression of AgifHSP70 exhibited an opposite trend. Besides the HSPs, we also quantified the expression levels of 11 antioxidant enzyme genes: AgifPOD, AgifSOD1, AgifSOD2, AgifSOD3, AgifCAT1, AgifCAT2, AgifGST1, AgifGST2, AgifGST3, AgifGST4 and AgifGST5. We found that the sex-specific expression of AgifSOD2, AgifSOD3, AgifPOD, AgifGST1 and AgifGST3 were highly consistent with sex-specific heat shock survival rates at 35°C. Furthermore, when the temperature was above 30°C, the activities of GST, SOD, CAT and POD were significantly increased; however, there was no significant difference of the CAT activity between the male and female at 35°C. Collectively, all of these results suggested that the protection of thermal damage is coordinated by HSPs and antioxidant enzymes in A. gifuensis. Based on the heat tolerance abilities of many aphid natural enemies, we also discussed an integrated application strategy of many aphid enemies in summer.

18.
Sci Rep ; 7(1): 14412, 2017 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-29089507

RESUMO

Ozone (O3) is a major air pollutant that has a profound effect on whole ecosystems. In this study we studied how hO3 affected the transmission of the Tomato yellow leaf curl China virus (TYLCCNV), a begomovirus, by the Q biotype Bemisia tabaci in a persistent, circulative manner. We found hO3 affected the transmission of TYLCCNV via the effect of it on the microbial community of the transmitting insect, such as Candidatus Hamiltonella, Ralstonia, Diaphorobacter, Caldilineaceae, Deinococcus, Rickettsia, Thysanophora penicillioides and Wallemia ichthyophaga. We concluded that hO3 decreased the resistance of acquiring virus tomatoes, and decreased the immune response and increased the endurance to extreme environments of viruliferous whiteflies by altering the composition and abundance of the microbial environments inside the body and on the surface of whitefly, as a result, it enhanced the TYLCV transmission rate by the Q biotype whitefly.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Begomovirus , Hemípteros/microbiologia , Insetos Vetores/microbiologia , Ozônio/efeitos adversos , Animais , Begomovirus/metabolismo , Resistência à Doença , Regulação da Expressão Gênica de Plantas , Hemípteros/imunologia , Hemípteros/virologia , Insetos Vetores/imunologia , Insetos Vetores/virologia , Solanum lycopersicum/imunologia , Solanum lycopersicum/virologia , Microbiota/fisiologia , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Doenças das Plantas/virologia , Proteínas de Plantas/metabolismo
19.
J Agric Food Chem ; 65(11): 2337-2344, 2017 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-28271709

RESUMO

On the basis of prior work, cytochrome P450 CYP9A61 was found to be enriched in fat bodies and during feeding stages, and transcription was induced by λ-cyhalothrin in Cydia pomonella. In this study, recombinant CYP9A61 was expressed in Escherichia coli and Pichia pastoris, and its biochemical properties were investigated. Substrate saturation curves and biochemical properties revealed that, in the presence of glycosylation, the yeast-secreted CYP9A61 exhibited a higher affinity for the substrate p-nitroanisole and was found to be more stable at certain pHs and temperatures than bacterially produced CYP9A61. Half-inhibitory concentrations (IC50) of three synthetic pyrethroids on both the bacterium- and yeast-expressed CYP9A61 suggested that recombinant CYP9A61 expressed in different hosts exhibits different inhibition properties. Taken together, our findings show that yeast-expressed CYP9A61 exhibits enzyme activity that is better than that expressed in bacteria and might be used for further metabolism assays to reveal the insecticide-detoxifying role of CYP9A61 in C. pomonella.


Assuntos
Sistema Enzimático do Citocromo P-450/genética , Escherichia coli/genética , Proteínas de Insetos/genética , Lepidópteros/enzimologia , Pichia/genética , Animais , Sistema Enzimático do Citocromo P-450/química , Sistema Enzimático do Citocromo P-450/metabolismo , Estabilidade Enzimática , Escherichia coli/metabolismo , Expressão Gênica , Concentração de Íons de Hidrogênio , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Cinética , Lepidópteros/genética , Pichia/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Temperatura
20.
J Cell Mol Med ; 21(9): 2022-2035, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28266122

RESUMO

Hypoxia stimulates excessive growth of vascular smooth muscle cells (VSMCs) contributing to vascular remodelling. Recent studies have shown that histone deacetylase inhibitors (HDIs) suppress VSMC proliferation and activate eNOS expression. However, the effects of HDI on hypoxia-induced VSMC growth and the role of activated eNOS in VSMCs are unclear. Using an EdU incorporation assay and flow cytometry analysis, we found that the HDIs, butyrate (Bur) and suberoylanilide hydroxamic acid (SAHA) significantly suppressed the proliferation of hypoxic VSMC lines and induced apoptosis. Remarkable induction of cleaved caspase 3, p21 expression and reduction of PCNA expression were also observed. Increased eNOS expression and enhanced NO secretion by hypoxic VSMC lines were detected using Bur or SAHA treatment. Knockdown of eNOS by siRNA transfection or exposure of hypoxic VSMCs to NO scavengers weakened the effects of Bur and SAHA on the growth of hypoxic VSMCs. In animal experiments, administration of Bur to Wistar rats exposed to hypobaric hypoxia for 28 days ameliorated the thickness and collagen deposition in pulmonary artery walls. Although the mean pulmonary arterial pressure (mPAP) was not obviously decreased with Bur in hypoxic rats, right ventricle hypertrophy index (RVHI) was decreased and the oxygen partial pressure of arterial blood was elevated. Furthermore, cell viability was decreased and eNOS and cleaved caspase 3 were induced in HDI-treated rat pulmonary arterial SMCs. These findings imply that HDIs prevent hypoxia-induced VSMC growth, in correlation with activated eNOS expression and activity in hypoxic VSMCs.


Assuntos
Inibidores de Histona Desacetilases/farmacologia , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/enzimologia , Óxido Nítrico Sintase Tipo III/metabolismo , Animais , Apoptose/efeitos dos fármacos , Benzoatos/farmacologia , Butiratos/farmacologia , Hipóxia Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ácidos Hidroxâmicos/farmacologia , Hipóxia/patologia , Imidazóis/farmacologia , Masculino , Modelos Biológicos , Miócitos de Músculo Liso/efeitos dos fármacos , Óxido Nítrico/biossíntese , Artéria Pulmonar/efeitos dos fármacos , Ratos Wistar , Remodelação Vascular/efeitos dos fármacos , Vorinostat
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