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1.
BMC Genomics ; 21(1): 638, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32933469

RESUMO

BACKGROUND: Plant viruses maintain intricate interactions with their vector and non-vector insects and can impact the fitness of insects. However, the details of their molecular and cellular mechanisms have not been studied well. We compared the transcriptome-level responses in vector and non-vector aphids (Schizaphis graminum and Rhopalosiphum padi, respectively) after feeding on wheat plants with viral infections (Barley Yellow Dwarf Virus (BYDV) and Wheat dwarf virus (WDV), respectively). We conducted differentially expressed gene (DEG) annotation analyses and observed DEGs related to immune pathway, growth, development, and reproduction. And we conducted cloning and bioinformatic analyses of the key DEG involved in immune. RESULTS: For all differentially expressed gene analyses, the numbers of DEGs related to immune, growth, development, reproduction and cuticle were higher in vector aphids than in non-vector aphids. STAT5B (signal transducer and activator of transcription 5B), which is involved in the JAK-STAT pathway, was upregulated in R. padi exposed to WDV. The cloning and bioinformatic results indicated that the RpSTAT5B sequence contains a 2082 bp ORF encoding 693 amino acids. The protein molecular weight is 79.1 kD and pI is 8.13. Analysis indicated that RpSTAT5B is a non-transmembrane protein and a non-secreted protein. Homology and evolutionary analysis indicated that RpSTAT5B was closely related to R. maidis. CONCLUSIONS: Unigene expression analysis showed that the total number of differentially expressed genes (DEGs) in the vector aphids was higher than that in the non-vector aphids. Functional enrichment analysis showed that the DEGs related to immunity, growth and reproduction in vector aphids were higher than those in non-vector aphids, and the differentially expressed genes related to immune were up-regulated. This study provides a basis for the evaluation of the response mechanisms of vector/non-vector insects to plant viruses.


Assuntos
Afídeos/genética , Insetos Vetores/genética , Transcriptoma , Animais , Afídeos/metabolismo , Afídeos/patogenicidade , Afídeos/virologia , Dicistroviridae/patogenicidade , Geminiviridae/patogenicidade , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Insetos Vetores/metabolismo , Insetos Vetores/patogenicidade , Insetos Vetores/virologia , Janus Quinases/genética , Janus Quinases/metabolismo , Luteovirus/patogenicidade , Fator de Transcrição STAT5/genética , Fator de Transcrição STAT5/metabolismo , Triticum/parasitologia , Triticum/virologia
2.
J Mol Recognit ; 32(4): e2769, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30419606

RESUMO

Molecular recognition in water is an important challenge in supramolecular chemistry. Surface-core double cross-linking of template-containing surfactant micelles by the click reaction and free radical polymerization yields molecularly imprinted nanoparticles (MINPs) with guest-complementary binding sites. An important property of MINP-based receptors is the surface-cross-linking between the propargyl groups of the surfactants and a diazide cross-linker. Decreasing the number of carbons in between the two azides enhanced the binding affinity of the MINPs, possibly by keeping the imprinted binding site more open prior to the guest binding. The depth of the binding pocket can be controlled by the distribution of the hydrophilic/hydrophobic groups of the template and was found to influence the binding in addition to electrostatic interactions between oppositely charged MINPs and guests. Cross-linkers with an alkoxyamine group enabled two-stage double surface-cross-linking that strengthened the binding constants by an order of magnitude, possibly by expanding the binding pocket of the MINP into the polar region. The binding selectivity among very similar isomeric structures also improved.


Assuntos
Micelas , Nanopartículas/química , Polímeros/química , Reagentes de Ligações Cruzadas/química , Interações Hidrofóbicas e Hidrofílicas , Água/química
3.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 49(2): 299-303, 2018 Mar.
Artigo em Zh | MEDLINE | ID: mdl-29737078

RESUMO

OBJECTIVE: To determine the prevalence and determinants of smoking in middle school students in priority areas for HIV control in Liangshan of Sichuan Province. METHODS: Students were randomly selected in all of the schools located in the priority areas for HIV control in Liangshan. A questionnaire survey was conducted,collecting data in relation to socio-demographic characteristics of the participants,their smoking behavior,drug abuse in family members,and HIV infections in family members. Risk factors associated with smoking were identified using univariate and multivariate statistical analyses. RESULTS: About 21.3% of respondents were smoking at the time of survey; 33.4% attempted smoking; 5% were heavy smokers; and 16.8% started smoking before 13 years old. The Logistic regression analysis identified male gender,senior high school students,poor academic records,low household income,rural residency,family drug abuse and HIV infections as predictors of attempted smoking. Male gender,minority ethnicity,average academic records,broken family,medium and high household income,family drug abuse and HIV infections were identified as predictors of smoking. Male gender,senior high school students,low or medium academic records,rural residency,and family drug abuse were identified as predictors of heavy smoking. Male gender,broken family,average academic records,medium or high household income,family drug abuse and HIV infections were associated with smoking before thirteen. CONCLUSION: Smoking rate in middle school students in the priority areas for HIV control in Liangshan is high. They start smoking at a young age. School smoking control programs should place priorities on those who are in the groups of boys,minority ethnicity,senior high school students,rural residency,poor academic records,and those with family drug abuse and HIV infections.


Assuntos
Infecções por HIV/epidemiologia , Fumar/epidemiologia , Inquéritos e Questionários , Adolescente , Família , Feminino , Humanos , Renda , Masculino , Prevalência , Fatores de Risco , População Rural , Instituições Acadêmicas , Estudantes , Transtornos Relacionados ao Uso de Substâncias/epidemiologia
4.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 49(3): 463-468, 2018 May.
Artigo em Zh | MEDLINE | ID: mdl-30014652

RESUMO

OBJECTIVE: To investigate drug knowledge of middle school students in HIV prone areas in Liangshan of Sichuan Province. METHODS: Students were randomly selected from the middle schools located in the HIV prone areas in Liangshan. A questionnaire survey was conducted. Drug knowledge of the respondents and associated factors were analyzed. RESULTS: Of the 10 749 respondents,10.1% had wrong knowledge about drugs. The respondents of male gender and minority ethnicity in the region and those who were in a lower grade,had poor academic records,more sisters,and a schoolmate taking drugs,and lived in a family with HIV infected member were more likely to had poor drug knowledge. By contrast,the respondents who had a peasant father,lived with both parents,resided in a city or township,self-rated in the middle and low 1/3 of wealth,lived in a community with >50% school attendance,and had a family member taking drugs were less likely to have wrong drug knowledge. CONCLUSION: Middle school students in the HIV prone areas in Liangshan have poor drug knowledge. Socioeconomic factors influence the drug knowledge of students,which require systematic interventions.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Drogas Ilícitas , Estudantes , China , Feminino , Infecções por HIV , Humanos , Masculino , Instituições Acadêmicas , Fatores Socioeconômicos , Inquéritos e Questionários
5.
Zhonghua Yu Fang Yi Xue Za Zhi ; 49(11): 967-72, 2015 Nov.
Artigo em Zh | MEDLINE | ID: mdl-26833006

RESUMO

OBJECTIVE: To investigate the survival time and its impact factors among AIDS patients who initially received antiretroviral treatment (ART) of Liangshan Yi Autonomous Prefecture, Sichuan province. METHODS: A retrospective cohort study was conducted to analyze the information of AIDS patients over 18 years old initially received ART in Liangshan Yi Autonomous Prefecture during 2005-2013, which were downloaded from Chinese AIDS Antiretroviral Therapy DATA Fax Information System. Cox proportion hazard regression model was used to identify impact factors related survival time. RESULTS: Among 8 310 ART AIDS patients who initially received ART, their mean age was (34.59 ± 9.10) years old, 65.50% (5 443 cases) were infected with HIV through injecting drug use, the mean time from testing HIV positive to starting ART were (24.68 ± 21.69) months. 436 cases died of AIDS related diseases, 28.67% (125 cases) of them died within the first 6 months of treatment. The cumulative survival rate of receiving ART in 1, 2, 3, 4 5 years were 97.11%, 93.41%, 90.61%, 88.81%, 86.02%, respectively. Multivariate Cox regression analysis showed the male patients receiveing ART were at a higher risk death of AIDS related diseases compared to the females (HR = 1.57, 95% CI: 1.13-2.182), the patients infected with HIV through injecting drug use were at a higher risk deathcompared to the infected through heterosexual transmission (HR = 1.64, 95% CI: 1.20-2.24), before the treatment patients with tuberculosis in recent1 year had higher death hazard as compared to those without tuberculosis (HR = 1.53, 95% CI: 1.05-2.21), in the treatment of the first 3 months of AIDS related diseases or symptoms of AIDS patients had higher death hazard as compared to those not suffer these diseases (HR = 1.80, 95% CI: 1.39-2.34). The patients with baseline CD4 (+) T lymphocytes cell counts < 50/µl (HR = 9.79, 95% CI: 6.03-15.89), 50-199/µl (HR = 3.26, 95% CI: 2.32-4.59), 200-349/µl (HR = 1.69, 95% CI: 1.22-2.34), were at a higher risk death than those with CD4 (+) T lymphocytes cell counts ≥ 350/µl. CONCLUSION: Accumulate survival rate was higher after initial antiretroviral treatment among AIDS patients in Liangshan Yi Autonomous Prefecture, Sichuan province. AIDS patients who are males, have tuberculosis in recent year, infected HIV via route of intravenous drug use, with AIDS-related illness or symptoms in 3 months before ART, lower baseline CD4 (+) T lymphocyte count have higher risk of death.


Assuntos
Síndrome da Imunodeficiência Adquirida/mortalidade , Antirretrovirais/uso terapêutico , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Adulto , Povo Asiático , China , Feminino , Humanos , Contagem de Linfócitos , Masculino , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Abuso de Substâncias por Via Intravenosa , Taxa de Sobrevida , Tuberculose/complicações
6.
J Agric Food Chem ; 72(19): 10828-10841, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38691839

RESUMO

Chemosensory proteins (CSPs) constitute a class of olfactory proteins localized in insect sensory organs that serve a crucial function in decoding external chemical stimuli. This study aims to elucidate the involvement of CrufCSP3 in olfactory perception within the context of Cotesia ruficrus, an indigenous endoparasitoid targeting the invasive pest Spodoptera frugiperda. Through fluorescence-competitive binding assays and site-directed mutagenesis, we pinpointed four amino acids as pivotal residues involved in the interaction between CrufCSP3 and five host-related compounds. Subsequent RNA interference experiments targeting CrufCSP3 unveiled a reduced sensitivity to specific host-related compounds and a decline in the parasitism rate of the FAW larvae. These findings unequivocally indicate the essential role of CrufCSP3 in the chemoreception process of C. ruficrus. Consequently, our study not only sheds light on the functional importance of CSPs in parasitic wasp behavior but also contributes to the development of eco-friendly and efficacious wasp behavior modifiers for effectively mitigating pest population surges.


Assuntos
Proteínas de Insetos , Spodoptera , Vespas , Animais , Vespas/química , Vespas/fisiologia , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Proteínas de Insetos/química , Larva/crescimento & desenvolvimento , Interações Hospedeiro-Parasita , Percepção Olfatória
7.
Int J Biol Macromol ; 274(Pt 2): 133491, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38944096

RESUMO

Cotesia ruficrus presents a promising local natural enemy for controlling the invasive fall armyworm Spodoptera frugiperda in China. However, the mechanisms underlying how C. ruficrus locates its target pest remain unclear. In this study, we analyzed the expression patterns of 18 CrufOBPs across different developmental stages of C. ruficrus, and found that CrufOBP1 exhibited consistent and high expression levels in female adults. CrufOBP1 transcript was predominantly localized in sensilla placodea and sensilla trichodea on the antennae. Additionally, we confirmed the binding properties of CrufOBP1 protein to various cuticular compounds of S. frugiperda larvae. Subsequent electroantennogram and behavioral assays revealed that 1-(2-hydroxy-5-methylphenyl)-ethanone attracted female C. ruficrus, consequently increased the parasitism rate. However, upon silencing CrufOBP1, females exhibited reduced attraction towards 1-(2-hydroxy-5-methylphenyl)-ethanone, indicating the crucial role of CrufOBP1 in the chemoreception of C. ruficrus. These findings shed light on the kairomone-based mechanism employed by C. ruficrus to locate S. frugiperda larvae and hold a promise for the development of environmentally friendly pest management strategies.


Assuntos
Proteínas de Insetos , Receptores Odorantes , Spodoptera , Vespas , Animais , Feminino , Proteínas de Insetos/genética , Proteínas de Insetos/fisiologia , Larva , Receptores Odorantes/genética , Receptores Odorantes/fisiologia , Sensilas/metabolismo , Vespas/fisiologia
8.
Insects ; 15(8)2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39194775

RESUMO

Parasitoids have the potential to alter the gut microbiota of their host insects post-parasitization, thereby influencing the host's physiological functions and creating a more favorable environment for the survival of the parasitoid's progeny. Cotesia ruficrus is a native enemy of the important invasive fall armyworm (FAW) pest, Spodoptera frugiperda, in China, exhibiting significant pest control capabilities. To investigate the impact of C. ruficrus on the gut bacteria of FAW caterpillars following parasitism, we used 16S rRNA sequencing technology to analyze the diversity and richness of gut bacteria in both long-term laboratory and short-term laboratory FAW caterpillars. The results revealed Enterococcus as the predominant bacteria across all treatments, while no significant differences were observed in the diversity and richness of gut bacteria between non-parasitized and parasitized long-term laboratory FAW caterpillars. Similarly, while the diversity of gut bacteria in non-parasitized and parasitized short-term laboratory FAWs showed no significant variance, a marked discrepancy in richness was noted. Moreover, the richness of gut bacteria in short-term laboratory FAW caterpillars surpassed that of their long-term laboratory counterparts. In addition, it was found that Corynebacterium existed only in the intestinal tract of FAW caterpillars that were parasitized by C. ruficrus. These results substantiate that C. ruficrus parasitization can alter the gut microbiota of FAW caterpillars, providing valuable insights into the interplay between gut microbiota and the dynamics of parasitoid-host interactions.

9.
Materials (Basel) ; 17(5)2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38473655

RESUMO

Aeolian sand and loess are both natural materials with poor engineering-related properties, and no research has been devoted to exploring aeolian sand-loess composite materials. In this study, we used aeolian sand and loess as the main raw materials to prepare unfired bricks by using the pressing method, along with cement, fly ash, and polypropylene fiber. The effects of different preparation conditions on the physical properties of the unfired bricks were investigated based on compressive strength, water absorption, and softening tests and a freeze-thaw cycle test combined with X-ray diffraction and scanning electron microscope analysis to determine the optimal mixing ratio for unfired bricks, and finally, the effects of fibers on the durability of the unfired bricks were investigated. The results reveal that the optimal mixing ratio of the masses of aeolian sand-loess -cement -fly ash-polypropylene fiber-alkali activator-water was 56.10:28.05:9.17:2.40:0.4:0.003:4.24 under a forming pressure of 20 MPa. The composite unfired bricks prepared had a compressive strength of 14.5 MPa at 14 d, with a rate of water absorption of 8.8%, coefficient of softening of 0.92, and rates of the losses of frozen strength and mass of 15.93% and 1.06%, respectively, where these satisfied the requirements of environmentally protective bricks with strength grades of MU10-MU15. During the curing process, silicate and sodium silicate gels tightly connected the particles of aeolian sand and the loess skeleton, and the spatial network formed by the addition of the fibers inhibited the deformation of soil and improved the strength of the unfired bricks.

10.
J Econ Entomol ; 116(3): 790-797, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37085154

RESUMO

The fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith), is a significant invasive pest identified as a serious threat to global agricultural production and food security. However, its ovipositional preference, larval feeding selectivity, and nutritional indices are less studied. Here, we investigated these traits of FAW when fed on maize, wheat, soybean, tomato, cotton, and Chinese cabbage, and analyzed the correlation between its nutritional indices and the nutritional contents of crops. The results showed that the highest number of eggs were laid on maize and the lowest number were laid on tomato. The highest feeding choice rate of third instar larvae was on maize, and the lowest was on Chinese cabbage. The fifth instar larvae showed the highest feeding choice rate on maize, but no significant differences were found among other crop species. The food consumption (FC), the relative growth rate (RGR), and the approximate digestibility (AD) were significantly higher on maize and wheat, while the efficiency of conversion of ingested food (ECI) and the efficiency of conversion of digested food (ECD) were significantly higher when fed on cotton and Chinese cabbage. The FC, the relative consumption rate (RCR), RGR, and AD were significantly and positively correlated with soluble sugar and protein contents of host plants, while the ECI and ECD were significantly and negatively correlated with the soluble sugar content. The present study indicates that FAW may cause potential economic losses to these crops besides maize, and these findings are valuable in managing and controlling this pest.


Assuntos
Brassica , Mariposas , Solanum lycopersicum , Animais , Spodoptera , Larva , Avaliação Nutricional , Produtos Agrícolas , Zea mays , Açúcares
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