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1.
Sci Total Environ ; 802: 149826, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34455281

RESUMO

The aim of the present study was to evaluate the enantioselective bioaccumulation, metabolism, and toxic effects of metolachlor and S-metolachlor in zebrafish. Five-month-old zebrafish were exposed to metolachlor and S-metolachlor for 28 days, then transferred to clean water and purified for 7 days. In the uptake phase, S-metolachlor was preferentially accumulated at low concentrations, while metolachlor was preferentially accumulated at high concentrations. The two chemicals were metabolized by >70% in zebrafish on the first day and showed same metabolic process. At the accumulation endpoint, S-metolachlor had no significant inhibitory effect on the enzymes activities of superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST) and developmental indicators of zebrafish. However, 300 µg/L metolachlor significantly inhibited the enzymes activities of SOD, CAT and GST and affected the liver development. The preferential enrichment of metolachlor at the high concentration may be the reason for its higher toxicity to zebrafish. Further research demonstrated that metolachlor significantly altered the expression of hypothalamic-pituitary-gonadal (HPG) axis-related genes, including gnrh2, gnrh3, lhß, 17ßhsd and cyp19a, thereby reducing the levels of testosterone (T) in females and sex hormones (estradiol and testosterone) in males. S-metolachlor increased the levels of estradiol (E2) in females by altering the expression of HPG axis-related genes such as fshß, cyp17, 17ßhsd and cyp19a. The mechanism of metolachlor and S-metolachlor on the endocrine disrupting effects of zebrafish is different, which may be sex-specific. 7 days after transferring the exposed zebrafish to clean water, most of the enzymes activities, sex hormone levels and related gene expression levels returned to normal, which may be related to the rapid metabolism of the two chemicals.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Acetamidas , Animais , Bioacumulação , Feminino , Masculino , Estereoisomerismo , Poluentes Químicos da Água/toxicidade
2.
J Appl Anim Welf Sci ; : 1-7, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34696632

RESUMO

The purpose of this study was to investigate the effect of short-term stimulation of classical music on the behavior of pullets and to explore whether classical music as an auditory enrichment factor reduces the fear level in pullets. One hundred and twenty 10-weeks'old Roman white pullets were randomly divided into two treatments of which one group was exposed to classic music (M), and another one was the control group (N). The music was played during 8:00-18:00 every day for 7 consecutive days. The behavior of the focal animals was observed from 11:00 to13:00 every day for 7 days. The results showed that during the observation period, the pullets in group M had more comforting (P < .05) and preening (P < .05), but less aggressive (P < .01) and feather-pecking (P < .01) behaviors than those in group N. No significant difference was found in other behaviors and the duration of tonic immobility between the two groups. Therefore, auditory enrichment as a means of environmental enrichment can increase the welfare level of pullets to a certain extent.

3.
Huan Jing Ke Xue ; 42(11): 5239-5249, 2021 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-34708963

RESUMO

Total suspended matter(TSM) is an important parameter that describes optical characteristics and water pollution level. Remote sensing was used to obtain suspended matter concentrations in the planar water body, which can monitor and analyze the reliability of turbidity and pollution levels. In this study, a semi-empirical model of suspended matter along the Yangtze River mainstream(from Chongqing to Shanghai) was constructed based on the field measured hyperspectral data and suspended matter concentration and its components, with reference to MODIS(1-4 band), Landsat 8(1-5 band), Sentinel 2(2-6 band), HJ-B1(1-4 band), and other commonly used band ranges. The results show that:① Turbidity and TSM of the Yangtze River mainstream increased from Chongqing to Shanghai during the dry season, whereas the proportion of OSM to TSM(OSM/TSM) decreased from Chongqing to Shanghai. ② The spectral properties of chlorophyll-a were not obvious; however, it showed a bimodal spectral characteristic of suspended matter concentration. Due to the low concentration of suspended matter in the water(<114.68 mg·L-1), the first peak value was significantly higher than the second peak. However, peak reflection and position had an obvious "red shift" phenomenon in the direction of the wavelength. ③ The reflectance values of the Yangtze River mainstream were most sensitive to the concentration of suspended matter in the 600-710 nm and 475-550 nm bands. Most of these fall in the green and red band of MODI, Landsat 8, Sentinel 2, and HJ-1B satellites. Therefore, the commonly used satellites have a band setting to detect the inversion of turbidity degree index of the Yangtze River main stream water body. The Sentinel 2 satellite band is most suitable for the inversion of suspended matter concentration in the Yangtze River mainstream. The mean absolute percentage error(MAPE) and root mean square error(RMSE) of the optimal exponential model were 10.23 mg·L-1 and 23%, respectively.


Assuntos
Rios , Água , China , Monitoramento Ambiental , Tecnologia de Sensoriamento Remoto , Reprodutibilidade dos Testes
4.
Zhen Ci Yan Jiu ; 46(10): 863-8, 2021 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-34698461

RESUMO

OBJECTIVE: To observe the effect of Lingnan fire needling combined with artificial tears in the treatment of xerophthalmia. METHODS: A total of 86 xerophthalmia patients were equally and randomly divided into treatment group and control group. The patients of both groups were received treatment with 0.1% sodium hyaluronate eye drops in their eyes 3 times a day, one drop in each eye. In addition, the patients of treatment group also treated by Lingnan fire needling on bilateral Shaoze (SI1), Neichengqi and beside lacrimal puncta once a week. The treatment was conducted for 4 consecutive weeks. Before and after 4 weeks of treatment, the clinical efficacy, visual acuity, intraocular pressure, ocular symptom score, OSDI score, fluorescence staining (FL) score, schemer I, tear menisci height, tear film break-up time (BUT) and eye redness index were recorded and evaluated. RESULTS: After the treatment, self-comparison showed that the symptom score, OSDI score, FL score and eye redness index were significantly decreased (P<0.05), and BUT was notably increased in both groups (P<0.05) in comparison with their own pre-treatment. The tear menisci height in the treatment group was higher than that before the treatment (P<0.05). Comparison between the two groups showed that the symptom score, OSDI score and eye redness index were obviously lower in the treatment group than in the control group (P<0.05), whereas the BUT and tear menisci height were evidently higher (P<0.05). The total effective rate of the treatment group was 84.88% (73/86), better than 76.74% (66/86) of the control group (P<0.05). CONCLUSION: Lingnan fire needling combined with 0.1% sodium hyaluronate eye drops is more effective than simple sodium hyaluronate eye drops for xerophthalmia patients, with significant curative effect and no adverse reactions.


Assuntos
Agulhamento Seco , Ácido Hialurônico/uso terapêutico , Soluções Oftálmicas/uso terapêutico , Xeroftalmia , Humanos , Lágrimas , Xeroftalmia/tratamento farmacológico
5.
Poult Sci ; 100(12): 101492, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34695632

RESUMO

In order to investigate the effect of intermittent mild cold stimulation (IMCS) on immune function of spleens and adaptability to cold stress in broilers, 400 healthy 1-day-old Ross-308 chickens were divided into 5 groups: CC (control) reared in normal thermal environment from 1 to 49 d; CS3, CS4, CS5, and CS6 (treatments) raised at 3°C below the temperature of CC for 3, 4, 5, or 6 h at 1-d intervals from 15 to 35 d, respectively. Subsequently, CS3-6 was raised at 20°C from 36 to 49 d. At 50 d, all groups were exposed to acute cold stress (ACS) for 12 h. The spleen immunity index at 22, 29, 36, 43, and 49 d, expression levels of toll-like receptors (TLRs), cytokines and immunoglobulins at 22, 43, and 49 d and heat shock proteins (HSPs) before and after ACS at 50 d were examined. The spleen index of broilers aged 22 to 49 d did not differ between CS and CC (P > 0.05), and the spleen index of CS5 was higher than that of CS3 at 49 d (P < 0.05). The mRNA levels of TLR5, TLR15, TLR21, and IL-2 in CS3, TLR3, TLR4, TLR15, TLR21, IL-2, IL-6, and IFN-ϒ in CS4, TLR1, TLR3, TLR4, TLR21, IL-2, IFN-a, IFN-ϒ, IgA, and IgG in CS6, but all TLRs, immunoglobulins and cytokines except IFN-ϒ in CS5 differential expressed stably compared with CC at 43 and 49 d (P < 0.05). Compared with Pre-ACS, the mRNA levels of HSP60, HSP70, and HSP90 were upregulated in CS after ACS (P < 0.05). Except for HSP90 mRNA and HSP70 protein in CS6, and HSP90 protein in CS3, the levels of HSPs after ACS in all treatment groups were higher than those in CC (P < 0.05), and the highest HSPs levels after ACS were found in CS5. We concluded that IMCS could enhance immunity of spleens and adaptability to ACS in broilers, besides CS5 was the optimal program.


Assuntos
Galinhas , Baço , Animais , Temperatura Baixa , Resposta ao Choque Frio , Citocinas/genética
6.
Transl Psychiatry ; 11(1): 437, 2021 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-34420033

RESUMO

Magnetic seizure therapy (MST) has established efficacy in the treatment of depression and a growing evidence base in the treatment of depression. We conducted the first systematic review and meta-analysis of the efficacy of MST in anti-depressive treatment and its impact on cognitive function (INPLASY registration number: INPLASY202170061). We searched for controlled trials published in English between 1 January 2001 to 31 December 2020 in PubMed, EMBASE, Cochrane Library, Web of Science, and PsycINFO databases. The evaluation process strictly followed the Cochrane bias risk assessment tool into the literature, and Meta-analysis was performed according to the Cochrane System Reviewer's Manual. Data from a total of 285 patients from 10 studies were retained in the quantitative synthesis. The results showed no significant difference between MST and ECT in the antidepressant effect (SDM -0.13 [-0.78;0.52]). Compared with ECT, MST showed shorter recovery time (MD -5.67 [-9.75; -1.60]) and reorientation time (MD -14.67 [-27.96; -1.41]); and MST showed less cognitive impairment on the immediate recall of words (SDM 0.80 [0.35;1.25]), delayed recall of words (SDM 0.99 [0.01;0.74]), visual-spatial immediate memory (SDM 0.51 [0.20;0.83]), visual-spatial delayed memory (SDM 0.57 [0.11;1.02]), and the verbal fluency (SDM 0.51 [0.20;0.83]). Our evidence-based study is the first meta-analysis on the efficacy of MST in anti-depressive treatment and its effect on cognitive function. It showed that the curative effect of MST in anti-depressive treatment is equivalent to that of ECT. Besides, depressive patients with MST benefit more from cognitive function compared with ECT.


Assuntos
Transtorno Depressivo Maior , Eletroconvulsoterapia , Cognição , Transtorno Depressivo Maior/terapia , Humanos , Memória , Convulsões
7.
Ecotoxicol Environ Saf ; 224: 112668, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34450428

RESUMO

Ammonia is an acknowledged environment pollutant in atmosphere with irritating smell. Previous studies have shown that excessive ammonia has toxic effects on farm animals and humans. However, the detail toxicity mechanism of ammonia to pigs is still unknown so far. In order to clarify the mechanism of ammonia toxicity, we established a porcine exogenous ammonia poisoning model and assessed the effects of ammonia on the gut-brain axis by transcriptome sequencing, histological observation and chemical analysis. Our results showed that after 30 d of ammonia exposure, 578 differentially expressed genes (DEGs) and 407 DEGs were obtained in the hypothalamus and jejunum, respectively. These DEGs were enriched into Gene Ontology terms associated with inflammation, oxidative metabolism, apoptosis, and the highly expressed genes among these DEGs were verified by real-time quantitative PCR. The content of glutathione and the activities of glutathione peroxidase and superoxide dismutase were significantly decreased, while malondialdehyde content was increased after ammonia exposure. Corticotropin releasing factor, substance P, 5-hydroxytryptamine and ghrelin contents in serum elevated significantly. Furthermore, pathologic observation in the ammonia group revealed infiltration of lymphocytes in the hypothalamus and significant decrease of jejunal epithelial cells. Our results indicated that ammonia exposure mediated changes in transcriptional profiles, pathological damage, oxidative stress and brain-gut peptide of the pig jejunum and hypothalamus, and induced the imbalance of the brain-gut axis through the "oxidative stress-inflammation-apoptosis" interaction network. Our study not only provides a new perspective for the toxicity assessment of ammonia, but also enriches the toxicology mechanism of ammonia.

8.
Water Res ; 204: 117564, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34455157

RESUMO

CO2 exchanges across the water-air interface in rivers and lakes are currently believed to be responsible for the dominant share of global aquatic CO2 emissions. The gas transfer velocity (k600) is the key factor that constrains the CO2 fluxes. It is also the most problematic to establish because of its high spatial and temporal variability. Here, we have evaluated the seasonal and spatial dynamics in k600 values and their physical and chemical controlling processes by gas tracer and floating chamber (FC) methods in three reaches of a low-gradient stream channel (Guancun surface stream, 'GSS') in a karst terrain in subtropical southwestern China in December 2016 and March, July and September 2017. The k600 values were highly variable in space and time in this small stream. Physical processes, including the velocity of the stream and its slope, were found to control the variations of k600. The k600 values recorded in the dry season (March and December) were at minimal levels due to very slow flow and gentle slope, and were also affected by complexation in the solute-enriched waters. The characteristics high pH and low turbulence of gentle streams in carbonate karst areas are conducive to such complexation, which is of great significance in the limiting CO2 degassing in such regions. We have obtained the first k600 prediction model for small streams in subtropical karst regions. In conclusion, we present a comprehensive approach for predicting the k600 values in small channels by comparison of independent SF6 gas tracer and floating chamber methods.


Assuntos
Dióxido de Carbono , Rios , Dióxido de Carbono/análise , Carbonatos , Monitoramento Ambiental , Lagos , Estações do Ano
9.
Pest Manag Sci ; 77(12): 5566-5575, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34390298

RESUMO

BACKGROUND: Triflumezopyrim, a novel commercialized mesoionic chemical insecticide, has been confirmed as a promising insecticide for efficiently controlling the brown planthopper, Nilaparvata lugens (Stål). Here, a laboratory triflumezopyrim-resistant (TR) strain and an isogenic susceptible (TS) strain were established to characterize the inheritance and fitness costs of triflumezopyrim resistance in N. lugens. RESULTS: After 29 generations of successive selection with triflumezopyrim, the TR strain developed a 155.23-fold higher resistance level than the TS strain. The median lethal concentration (LC50 ) values from progenies (F1 RS and F1 SR) of reciprocal crosses between TR and TS strains suggested that triflumezopyrim resistance in N. lugens was autosomal and codominant. Chi-square analyses of self-bred and backcrossed progenies suggested that the resistance results from a polygenic effect. Compared to the TS strain, the TR strain showed a lower relative fitness (0.62) with a significantly decreased female adult period, longevity, total fecundity, egg hatchability, intrinsic rate of increase (r), finite rate of increase (λ), net reproductive rate (R0 ), and prolonged pre-adult period and total preoviposition period (TPOP). CONCLUSION: The inheritance mode of triflumezopyrim resistance in N. lugens was characterized as autosomal, codominant and polygenic. The resistance had a fitness cost, which may be an important factor limiting the evolution of resistance. These findings provide valuable information for optimizing resistance management strategies to delay triflumezopyrim resistance development and maintain sustainable control of N. lugens. © 2021 Society of Chemical Industry.


Assuntos
Hemípteros , Inseticidas , Animais , Feminino , Hemípteros/genética , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Piridinas , Pirimidinonas
10.
Microb Ecol ; 2021 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-34302509

RESUMO

Understanding the composition of microorganismal communities hosted by insect pests is an important prerequisite for revealing their functions and developing new pest control strategies. Although studies of the structure of the microbiome of Nilaparvata lugens have been published, little is known about the dynamic changes in this microbiome across different developmental stages, and an understanding of the core microbiota is still lacking. In this study, we investigated the dynamic changes in bacteria and fungi in different developmental stages of N. lugens using high-throughput sequencing technology. We observed that the microbial diversity in eggs and mated adults was higher than that in nymphs and unmated adults. We also observed a notable strong correlation between fungal and bacterial α-diversity, which suggests that fungi and bacteria are closely linked and may perform functions collaboratively during the whole developmental period. Arsenophonus and Hirsutella were the predominant bacterial and fungal taxa, respectively. Bacteria were more conserved than fungi during the transmission of the microbiota between developmental stages. Compared with that in the nymph and unmated adult stages of N. lugens, the correlation between bacterial and fungal communities in the mated adult and egg stages was stronger. Moreover, the core microbiota across all developmental stages in N. lugens was identified, and there were more bacterial genera than fungal genera; notably, the core microbiota of eggs, nymphs, and mated and unmated adults showed distinctive functional enrichment. These findings highlight the potential value of further exploring microbial functions during different developmental stages and developing new pest management strategies.

11.
Anim Biosci ; 2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34293839

RESUMO

Objective: The objective of this study was to determine the effects of different social ranking order (SRO) and the enrichments (perch and dust-bath) allocation (EA) on behavior of laying hens in furnished cages. Methods: A total of 4 weeks in experiment period. 216 Hy-line brown layers beak-trimmed at 1 d of age were selected randomly at 14 weeks of age from a commercial farm, and randomly divided into 36 cages with 6 hens in each cage. High enrichments (perch and dust-bath) allocation (HEA) and low enrichments (perch and dust-bath) allocation (LEA) were provided. Video observations of behavior were obtained from the focal hens between 14 and 18 weeks of age and perching, dust-bathing and other general behaviors of the hens with different social orders were measured. Results: Perching behavior of high social ranking order hens (HSR) were significantly higher than that of medium social ranking order hens (MSR), and that of the MSR were significantly higher than that of low social ranking order hens (LSR) (P < 0.01), except for lying on perch (P > 0.05). The hens in the high enrichment allocation cage (HEAC) showed more lying behavior on perch than those in the low enrichment allocation cage (LEAC) (P < 0.01). The different SRO and EA did not affect dust-bathing behavior except vertical wing-shaking behavior (P < 0.05). The LEA did not affect general behaviors (P > 0.05), except standing and preening behaviors (P < 0.01 and P < 0.05), of which the hens in the HEAC showed less standing (P < 0.01) and more preening behavior than the hens in the LEAC. Conclusion: The SRO of laying hens has a significant effect on the perching behaviors, but SRO and EA have little effect on dust-bathing and general behaviors.

12.
Pestic Biochem Physiol ; 176: 104875, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34119220

RESUMO

In the present study, the aryl hydrocarbon receptor (AhR) and aryl hydrocarbon receptor nuclear translocator (ARNT) of Nilaparvata lugens were cloned and identified. The NlAhR and NlARNT expression levels significantly increased after imidacloprid, etofenprox and isoprocarb treatments. Knockdowns of NlAhR and NlARNT increased the susceptibility of N. lugens to imidacloprid, etofenprox and isoprocarb, and the detoxification enzyme activities were also significantly decreased. In addition, NlCYP301A1, NlGSTt1 and NlCarE7 were significantly down-regulated after injections of dsNlAhR and dsNlARNT, with the NlCarE7 expression decreasing by greater than 80%. Moreover, after knocking down NlCarE7, the susceptibility of N. lugens to etofenprox and isoprocarb significantly increased. Both NlAhR and NlARNT bound the NlCarE7 promoter and significantly enhanced the transcriptional activity. Our research revealed the functional roles of transcription factors NlAhR and NlARNT in the detoxification metabolism of N. lugens. The results provide a theoretical basis for the pest management and comprehensive control of N. lugens and increase our knowledge of insect toxicology.


Assuntos
Translocador Nuclear Receptor Aril Hidrocarboneto , Hemípteros , Receptores de Hidrocarboneto Arílico , Animais , Translocador Nuclear Receptor Aril Hidrocarboneto/genética , Hemípteros/genética , Hemípteros/metabolismo , Resistência a Inseticidas/genética , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo
13.
Ann Med ; 53(1): 900-907, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34121552

RESUMO

BACKGROUND: Abdominal wound dehiscence (AWD) is a major complication of abdominal surgery, and neonates are a group with a high risk of AWD, which has serious consequences or can even result in death. The purpose of this study is to explore the risk factors for neonatal AWD and construct a predictive model. METHODS: The clinical data of 453 cases that underwent neonatal laparotomy from June 2009 to June 2020 were retrospectively analyzed, among which 27 cases of AWD were identified. Nine factors, including gender, age at admission, weight at admission, preterm delivery, level of preoperative anaemia, hypoalbuminemia, operation time, incision length, and incision type, were analyzed to explore their correlation with neonatal AWD. RESULTS: The incidence of neonatal AWD was 6.0% (27/453), among which partial wound dehiscence accounted for 4.9% (22/453) and complete wound dehiscence accounted for 1.1% (5/453). Hypoproteinemia and incision type were the independent risk factors for neonatal AWD, and weight at admission was a protective factor for AWD in the multivariate models. All these factors were incorporated to construct a nomogram, and a calibration curve was plotted. The result indicated that the actual risk was close to the predicted risk when the predicted risk rate was greater than about 35%. CONCLUSIONS: Neonatal AWD is closely related to hypoproteinemia and incision contamination. Our predictive model showed the potential to provide an individualized risk estimate of AWD for neonatal patients undergoing abdominal surgery.Key messagesNeonatal abdominal wound dehiscence (AWD) has a serious consequence and the incidence of neonatal AWD was about 6.0% and the complete AWD morbidity is 1.1%.Hypoproteinemia and incision type were the independent risk factors for neonatal AWD.Our predictive model showed the potential to provide an individualized risk estimate of AWD for neonatal patients undergoing abdominal surgery.


Assuntos
Hipoproteinemia , Deiscência da Ferida Operatória , Abdome/cirurgia , Humanos , Recém-Nascido , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Fatores de Risco , Deiscência da Ferida Operatória/epidemiologia , Deiscência da Ferida Operatória/etiologia
14.
ISME J ; 15(12): 3693-3703, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34188180

RESUMO

The interactions between insects and their bacterial symbionts are shaped by a variety of abiotic factors, including temperature. As global temperatures continue to break high records, a great deal of uncertainty surrounds how agriculturally important insect pests and their symbionts may be affected by elevated temperatures, and its implications for future pest management. In this study, we examine the role of bacterial symbionts in the brown planthopper Nilaparvata lugens response to insecticide (imidacloprid) under different temperature scenarios. Our results reveal that the bacterial symbionts orchestrate host detoxification metabolism via the CncC pathway to promote host insecticide resistance, whereby the symbiont-inducible CncC pathway acts as a signaling conduit between exogenous abiotic stimuli and host metabolism. However, this insect-bacterial partnership function is vulnerable to high temperature, which causes a significant decline in host-bacterial content. In particular, we have identified the temperature-sensitive Wolbachia as a candidate player in N. lugens detoxification metabolism. Wolbachia-dependent insecticide resistance was confirmed through a series of insecticide assays and experiments comparing Wolbachia-free and Wolbachia-infected N. lugens and also Drosophila melanogaster. Together, our research reveals elevated temperatures negatively impact insect-bacterial symbiosis, triggering adverse consequences on host response to insecticide (imidacloprid) and potentially other xenobiotics.

15.
Pest Manag Sci ; 77(10): 4476-4482, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34010497

RESUMO

BACKGROUND: Nilaparvata lugens, a destructive rice pest in Asia, has developed resistance to many insecticides, including the neonicotinoid clothianidin. CYP6ER1 plays an important role in N. lugens resistant to clothianidin, but only limited information on the transcriptional regulation of CYP6ER1 overexpression in clothianidin resistance is available. RESULTS: In this study, the transcription factor activator protein 1 (AP-1) was found to be overexpressed in a clothianidin-resistant strain of N. lugens and several field resistant populations. RNA interference-mediated silencing of NlAP-1 significantly decreased CYP6ER1 expression and increased the susceptibility of N. lugens to clothianidin. Additionally, NlAP-1 was highly expressed in egg and adult stages, and in midguts, and NlAP-1 was upregulated and induced to a greater extent in the clothianidin-resistant strain after exposure to clothianidin. Finally, dual-luciferase reporter assays confirmed the interaction between NlAP-1 and the two predicted binding sites in the CYP6ER1 promoter. CONCLUSION: NlAP-1 bound the -1388 to -1208-bp region of the CYP6ER1 promoter, enhancing its activity and then regulate the expression of CYP6ER1. These findings enhance our knowledge of the transcriptional regulation of the P450 genes that mediate insecticide resistance in insect pests. © 2021 Society of Chemical Industry.


Assuntos
Hemípteros , Inseticidas , Animais , Guanidinas , Hemípteros/genética , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Neonicotinoides , Nitrocompostos/farmacologia , Tiazóis , Fator de Transcrição AP-1
16.
J Anim Sci ; 99(5)2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33939813

RESUMO

An enriched environment is widely used to improve domestic animals' welfare and promote their natural behaviors. Music can reduce abnormal behavior in humans, nonhuman primates, and rodents. However, little is known about the effects of music on pigs. This study aims to explore the effects of repeated music stimulation on the behavior, physiology, and immunity of growing pigs. A total of 72 hybrid piglets (Large White × Duroc × Minpig) were randomly divided into three groups, including music (Mozart K.448, 60 to 70 dB), noise (recorded mechanical noise, 80 to 85 dB), and control (natural background sound, <40 dB), and 6 h sound stimulation was given per day (1000 to 1600 hours) from 40 to 100 d of age. The behavioral activities of the pigs were observed during the music stimulation, and their serum cortisol, salivary cortisol, and serum immune indices were also measured. Compared with the control group, the music group and noise group increased activity but decreased lying of pigs (P < 0.05). A significant increase in tail-wagging, playing, and exploring behaviors of pigs was found in the music group (P < 0.05), and the noise significantly increased the aggressive behavior of the pigs (P < 0.05). Tail-wagging, playing, exploring, manipulating, and aggressive behaviors decreased over time. Short-term (8 d) music stimulus had a lower cortisol level than that of the noise and control groups (P < 0.05), whereas long-term (60 d) music stimulus increased immunoglobulin G (IgG), interleukin-2 (IL-2), and interferon-gamma (IFN-γ) levels (P < 0.05) and decreased interleukin-4 (IL-4) level (P < 0.05). Long-term noise stimulus significantly reduced the level of IgG (P < 0.05) but did not affect the level of IL-2, IL-4, and IFN-γ levels (P > 0.05). In conclusion, short-term music stimulus (8 d) reduced the stress response, whereas long-term music stimulus (60 d) enhanced the immune responses. In addition, the noise increased the aggressive behavior, and long-term noise reduced the immunity of the growing pigs.


Assuntos
Música , Agressão , Animais , Hidrocortisona , Ruído/efeitos adversos , Suínos , Cauda
17.
3 Biotech ; 11(5): 218, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33968563

RESUMO

PhoX is an extracellular alkaline phosphatase that is widely found in cyanobacteria and plays an important role in the conversion of extracellular organophosphorus into soluble inorganic phosphorus. However, the phoX gene has not yet been experimentally confirmed to exist in bloom-forming Microcystis species. In this study, we identified a putative phoX gene (GenBank accession no. ARI79942.1) in M. aeruginosa PCC7806 and overexpressed it in Escherichia coli 21 (DE3). The expressed PhoX protein displayed phosphodiesterase and phosphomonoesterase activities. In contrast to other bacterial PhoX proteins, which are activated mainly by Ca2+, Microcysits PhoX was most strongly activated by Mg2+, followed by Co2+, Ca2+, Zn2+ and Mn2+, but it was inhibited by Ni2+. Sequence analysis showed that phoX was highly conserved in the Microcystis genus (DNA similarity > 96% between species). phoX expression responded significantly to different environmental phosphorus levels. When PCC7806 cells were cultured in phosphorus-deficient medium (BG11-P), phoX expression reached its highest level at 2 h and then decreased to a low level at 4 h. Organophosphate induced the expression of phoX; its expression reached the highest level at 4 h and was maintained at a high level at 6 h. Our results confirmed a putative phoX gene and demonstrated that the phoX gene of Microcystis is conserved.

18.
J Hazard Mater ; 414: 125513, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34030404

RESUMO

The controlled release of pesticides based on nanoparticle platforms has emerged as a new technology for increasing the efficiency of pesticides and for reducing environmental pollution because of their size-dependent and target-modifying properties. In the present study, pH/cellulase dual stimuli-responsive controlled-release formulations (PYR-HMS-HPC) were designed by grafting hydroxypropyl cellulose onto pyraclostrobin-loaded hollow mesoporous silica nanoparticles via an ester linkage. The PYR-HMS-HPC formulations were characterized by Fourier transform infrared spectroscopy, thermogravimetric analyzer, transmission electron microscope and scanning electron microscope. The results demonstrated that PYR-HMS-HPC with a loading capacity of 12.1 wt% showed excellent pyraclostrobin release behaviors in response to acidic environments and the introduction of cellulase, could effectively prevented pyraclostrobin from photolysis. Compared with commercial pyraclostrobin formulations, the PYR-HMS-HPC formulations showed much stronger and statistically significant fungicidal activity against Magnaporthe oryzae from 7 to 21 days. Furthermore, the Allium cepa chromosome aberration assay demonstrated that the PYR-HMS-HPC formulations reduced the genotoxicity of pyraclostrobin. These pH/cellulase dual stimuli-responsive controlled-release formulations are of great interest for sustainable on-demand crop disease protection.


Assuntos
Fungicidas Industriais , Nanopartículas , Ascomicetos , Celulose/análogos & derivados , Portadores de Fármacos , Porosidade , Dióxido de Silício
19.
Pest Manag Sci ; 77(9): 4159-4167, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33934482

RESUMO

BACKGROUND: Uridine diphosphate-glycosyltransferases (UGTs) are phase II metabolic enzymes involved in metabolism of toxins and resistance to insecticides in insect pests. Reactive oxygen species (ROS) induced by xenobiotics are important for activation of detoxification pathways. However, relationships between ROS and UGTs involved in toxin metabolism and insecticide resistance remain unclear. RESULTS: Here, involvement of dual oxidase (Duox)-dependent ROS in regulating UGT expression-mediated insecticide resistance in the brown planthopper (Nilaparvata lugens) was investigated. The overexpression of NlUGT386F2 contributed to the resistance of N. lugens to clothianidin. Furthermore, the ROS inhibitor (N-acetylcysteine) significantly reduced the expression of NlUGT386F2 and increased the susceptibility of N. lugens to clothianidin. Silencing the ROS producer Duox significantly increased the susceptibility of N. lugens to clothianidin through the down-regulation of NlUGT386F2 expression. CONCLUSION: NlDuox-dependent ROS regulates NlUGT386F2 expression-mediated clothianidin resistance in brown planthopper. These observations further our understanding of the metabolism of toxins and of insecticide-resistance in insect pests.


Assuntos
Hemípteros , Inseticidas , Animais , Oxidases Duais , Guanidinas , Hemípteros/genética , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Neonicotinoides , Espécies Reativas de Oxigênio , Tiazóis
20.
Toxins (Basel) ; 13(4)2021 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-33810599

RESUMO

Bee venom is a complex mixture composed of peptides, proteins with enzymatic properties, and low-molecular-weight compounds. Although the carboxylesterase in bee venom has been identified as an allergen, the enzyme's role as a venom component has not been previously elucidated. Here, we show the lipolytic activity of a bumblebee (Bombus ignitus) venom carboxylesterase (BivCaE). The presence of BivCaE in the venom secreted by B. ignitus worker bees was confirmed using an anti-BivCaE antibody raised against a recombinant BivCaE protein produced in baculovirus-infected insect cells. The enzymatic activity of the recombinant BivCaE protein was optimal at 40 °C and pH 8.5. Recombinant BivCaE protein degrades triglycerides and exhibits high lipolytic activity toward long-chain triglycerides, defining the role of BivCaE as a lipolytic agent. Bee venom phospholipase A2 binds to mammalian cells and induces apoptosis, whereas BivCaE does not affect mammalian cells. Collectively, our data demonstrate that BivCaE functions as a lipolytic agent in bee venom, suggesting that BivCaE will be involved in distributing the venom via degradation of blood triglycerides.


Assuntos
Venenos de Abelha/enzimologia , Abelhas/enzimologia , Carboxilesterase/metabolismo , Proteínas de Insetos/metabolismo , Lipólise , Triglicerídeos/metabolismo , Animais , Venenos de Abelha/genética , Venenos de Abelha/toxicidade , Abelhas/genética , Carboxilesterase/genética , Carboxilesterase/toxicidade , Concentração de Íons de Hidrogênio , Proteínas de Insetos/toxicidade , Especificidade por Substrato , Temperatura
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