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1.
Pestic Biochem Physiol ; 114: 90-6, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25175655

RESUMO

The western flower thrips (WFT) Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), an important pest of various crops in the world, has invaded China since 2003. To understand the risks and to determine possible mechanisms of resistance to thiamethoxam in WFT, a resistant strain was selected under the laboratory conditions. Cross-resistance and the possible biochemical resistance mechanisms were investigated in this study. A 15.1-fold thiamethoxam-resistant WFT strain (TH-R) was established after selection for 55 generations. Compared with the susceptible strain (TH-S), the selected TH-R strain showed extremely high level cross-resistance to imidaclothiz (392.1-fold) and low level cross-resistance to dinotefuran (5.7-fold), acetamiprid (2.9-fold) and emamectin benzoate (2.1-fold), respectively. No cross-resistance to other fourteen insecticides was detected. Synergism tests showed that piperonyl butoxide (PBO) and triphenyl phosphate (TPP) produced a high synergism of thiamethoxam effects in the TH-R strain (2.6- and 2.6-fold respectively). However, diethyl maleate (DEM) did not act synergistically with thiamethoxam. Biochemical assays showed that mixed function oxidase (MFO) activities and carboxylesterase (CarE) activity of the TH-R strain were 2.8- and 1.5-fold higher than that of the TH-S strain, respectively. When compared with the TH-S strain, the TH-R strain had a relative fitness of 0.64. The results show that WFT develops resistance to thiamethoxam after continuous application and thiamethoxam resistance had considerable fitness costs in the WFT. It appears that enhanced metabolism mediated by cytochrome P450 monooxygenases and CarE was a major mechanism for thiamethoxam resistance in the WFT. The use of cross-resistance insecticides, including imidaclothiz and dinotefuran, should be avoided for sustainable resistance management.


Assuntos
Carboxilesterase/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Inseticidas/farmacologia , Nitrocompostos/farmacologia , Oxazinas/farmacologia , Tiazóis/farmacologia , Tisanópteros/efeitos dos fármacos , Animais , Feminino , Fertilidade/efeitos dos fármacos , Resistência a Inseticidas/fisiologia , Masculino , Neonicotinoides , Tiametoxam , Tisanópteros/fisiologia
2.
J Glob Health ; 14: 04099, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38726560

RESUMO

Background: To explore trends of the association between body mass index (BMI) and age at menarche or spermarche and its urban-rural disparities from 1995 to 2019. Methods: A total of 912 753 children and adolescents - including 519 940 9-18 years old girls and 392 813 11-18 years old boys - were involved in six successive cross-sectional surveys conducted across 30 provinces in China from 1995 to 2019. Data on menarche and spermarche was collected using the status quo method, where same-gender physicians conducted face-to-face interviews to determine if children and adolescents had experienced their first menstrual cycle or ejaculation (yes/no). The median age at menarche or spermarche was estimated by probit analysis. Anthropometric measurements measured the height and weight of the study subjects. Children and adolescents were classified into thinness, normal range of weight, overweight, and obesity. t test was used to compare the differences in BMI between premenarchal and postmenarchal girls or prespermarcheal and postspermarcheal boys. Logistic regression was used to explore the associations between BMI/nutritional status and menarche or spermarche stratified by urban or rural residency status. Results: From 1995 to 2019, BMI in all age groups growth over time, and the values of BMI among children and adolescents under 15 who had menarche or spermarche were more significant than those without menarche or spermarche. In 2019, for girls, thinness was associated with delayed menarche (odds ratio (OR) = 0.26; 95% confidence interval (CI) = 0.24-0.28), while overweight (OR = 1.99; 95% CI = 1.85-2.14) and obesity (OR = 2.20; 95% CI = 1.92-2.53) was associated with advanced menarche. For boys, thinness was associated with delayed spermarche (OR = 0.71; 95% CI = 0.65-0.78), overweight was associated with advanced spermarche (OR = 1.08; 95% CI = 1.01-1.15) while obesity had no association with spermarche. The OR between BMI and menarche in 1995 was 1.35 (95% CI = 1.33-1.37), which decreased to 1.19 (95% CI = 1.18-1.20) by 2019. The OR between BMI and spermarche in 1995 was 1.10 (95% CI = 1.09-1.11), which decreased to 1.02 (95% CI = 1.02-1.03) by 2019. The trends by urban-rural stratification were consistent with the total sample. Conclusions: We have established a dose-response relationship between BMI and menarche in girls, whereas the association appears to be nonlinear in boys, and the associations were diminishing. Similar findings were observed in both urban and rural areas. Considering the dual adverse effects of obesity and early puberty on health, the results of this study suggest that sexual health education should be strengthened, especially among obese girls. Further research on the influencing factors and biological mechanisms of early puberty will be beneficial.


Assuntos
Índice de Massa Corporal , Menarca , Humanos , China/epidemiologia , Feminino , Adolescente , Masculino , Menarca/fisiologia , Criança , Estudos Transversais , Fatores Etários , População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Puberdade/fisiologia
3.
Ying Yong Sheng Tai Xue Bao ; 32(11): 3942-3952, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34898110

RESUMO

The supply and demand of ecosystem services are related to both natural ecosystems and socio-economic systems. The research on the supply and demand of ecosystem services would help enhance ecosystem management and achieve optimal allocation of resources, which ensures regional ecological security and sustainable development of socio-economic. Based on a systematic review of international literature, we comprehensively reviewed the conceptual connotation, evaluation metho-ds, and practical application of ecosystem service supply and demand. Although relatively abundant investigations have been conducted from the perspective of theoretical development, they are still scattered and lacking a coherent research framework. Based on expanding the scope of research on the supply and demand of ecosystem service, we constructued a research framework that referred to "qualitative-positioning-quantitative-policymaking" in accordance with the research pattern of "theory-methodology-practice". To promote the theoretical and practical research on the supply and demand of ecosystem service, future research needs to focus on the spatial delivery mechanism, strengthen the research on quantitative methods, deepen the management and application practice, and establish the evaluation mechanism of ecosystem service supply and demand application.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Desenvolvimento Sustentável
5.
Oncol Rep ; 38(5): 3177-3186, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29048683

RESUMO

Emerging evidence suggests that long non-coding RNAs (lncRNAs) may be involved in modulating various aspects of tumor biology and serve as potential therapeutic targets as well as novel biomarkers in the treatment of glioma. The present study investigated the role of lncRNA, Prader Willi/Angelman region RNA 5 (PAR5; also known as PWAR5), in glioma and its clinical significance in glioma cases. The expression levels of PAR5 were determined in clinical samples and U87, U251 cells using real-time reverse transcription quantitative polymerase chain reaction (qRT-PCR) analysis. The effects of PAR5 on cell proliferation, migration and invasion were determined using in vitro assays. RNA immunoprecipitation (RIP) and RNA pull-down assays, as well as the evauation of the expression of various oncogenes were carried out to reveal the underlying mechanisms. We found that PAR5 was significantly downregulated in glioma tissues and cell lines. Furthermore, PAR5 expression was negatively correlated with tumor size, World Health Organization (WHO) grade and Karnofsky performance score (KPS). Patients with low PAR5 expression in tumors had a worse overall survival compared to those with higher expression. Finally, in vitro restoration of PAR5 expression inhibited human glioma cell proliferation, invasion and migration by binding to EZH2 and regulating oncogene expression. This finding may provide a therapeutic approach for the future treatment of glioma.


Assuntos
Carcinogênese/genética , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Glioma/genética , RNA Longo não Codificante/genética , Adulto , Idoso , Movimento Celular/genética , Proliferação de Células/genética , Progressão da Doença , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Glioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Ligação Proteica
6.
Sci Bull (Beijing) ; 62(7): 503-507, 2017 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36659260

RESUMO

We performed angle-resolved photoemission spectroscopy studies on a series of FeTe1-xSex monolayer films grown on SrTiO3. The superconductivity of the films is robust and rather insensitive to the variations of the band position and effective mass caused by the substitution of Se by Te. However, the band gap between the electron- and hole-like bands at the Brillouin zone center decreases towards band inversion and parity exchange, which drive the system to a nontrivial topological state predicted by theoretical calculations. Our results provide a clear experimental indication that the FeTe1-xSex monolayer materials are high-temperature connate topological superconductors in which band topology and superconductivity are integrated intrinsically.

7.
Z Naturforsch C J Biosci ; 61(3-4): 251-6, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16729585

RESUMO

An efficient procedure has been developed for callus induction and cell suspension cultures of C. saxicola for the first time. Explant selection was carried out among leaf, stem and root to select a suitable type of explants capable of higher callus formation. Leaf explants thus selected showed maximum response to callus induction (67.1%). Modified B5 medium supplemented with 0.5 mg l(-1) 2,4-D plus 2 mg l(-1) BA was the most favorable medium for callus formation with the highest induction rate (94.8%) and greatest fresh weight of callus (1.7 g per explant). Cell suspension cultures were established by transferring 2-8 g fresh callus to 80 ml liquid B5 medium. An inoculum size of 8 g produced the greatest biomass accumulation, dehydrocavidine and berberine productions, which was 13.1 g l(-1), 8.0 mg l(-1) and 4.1 mg l(-1), respectively. In response to various sucrose concentrations from 10 g l(-1) to 80 g l(-1), cultures with 60 g sucrose l(-1) not only produced the highest dry biomass (18.5 g l(-1)) but also the highest formation of dehydrocavidine (11.6 mg l(-1)) and berberine (7.6 mg l(-1)). These prepared cell suspension cultures provided a useful material for further regulation of alkaloid biosynthesis and for enhanced production of valuable alkaloids on a large scale.


Assuntos
Corydalis/crescimento & desenvolvimento , Alcaloides/metabolismo , Biomassa , Técnicas de Cultura de Células/métodos , Divisão Celular/fisiologia , Corydalis/citologia , Corydalis/efeitos dos fármacos , Cinética , Reguladores de Crescimento de Plantas/farmacologia , Plantas Medicinais/citologia , Plantas Medicinais/crescimento & desenvolvimento , Sacarose/farmacologia
8.
Interv Neuroradiol ; 16(3): 286-9, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20977862

RESUMO

We describe a patient with dural arteriovenous fistula (DAVF) treated with Onyx-18 who developed isolated hypoglossal nerve palsy. This is the first case of isolated hypoglossal nerve palsy caused by Onyx-18 embolization. This complication suggests that over embolization with Onyx-18 in the treatment of hypoglossal canal DAVFs should be avoided, and transvenous embolization may be safer. Furthermore, prednisolone therapy should be carried out in the prophase of nerve palsy.


Assuntos
Malformações Vasculares do Sistema Nervoso Central/terapia , Dimetil Sulfóxido/efeitos adversos , Embolização Terapêutica/efeitos adversos , Doenças do Nervo Hipoglosso/etiologia , Polivinil/efeitos adversos , Malformações Vasculares do Sistema Nervoso Central/diagnóstico por imagem , Angiografia Cerebral , Humanos , Masculino , Pessoa de Meia-Idade , Língua/inervação
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