Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 58
Filtrar
1.
Opt Express ; 32(8): 14187-14199, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38859371

RESUMO

For segmented telescopes, achieving fine co-focus adjustment is essential for realizing co-phase adjustment and maintenance, which involves adjusting the millimeter-scale piston between segments to fall within the capture range of the co-phase detection system. CGST proposes using a SHWFS for piston detection during the co-focus adjustment stage. However, the residual piston after adjustment exceeds the capture range of the broadband PSF phasing algorithm( ± 30µm), and the multi-wavelength PSF algorithm requires even higher precision in co-focus adjustment. To improve the co-focus adjustment accuracy of CGST, a fine co-focus adjustment based on cross-calibration is proposed. This method utilizes a high-precision detector to calibrate and fit the measurements from the SHWFS, thereby reducing the impact of atmospheric turbulence and systematic errors on piston measurement accuracy during co-focus adjustment. Simulation results using CGST demonstrate that the proposed method significantly enhances adjustment accuracy compared to the SHWFS detection method. Additionally, the residual piston after fine co-focus adjustment using this method falls within the capture range of the multi-wavelength PSF algorithm. To verify the feasibility of this method, experiments were conducted on an 800mm ring segmented mirror system, successfully achieving fine co-focus adjustment where the remaining piston of all segments fell within ±15µm.

2.
Luminescence ; 39(6): e4804, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38859763

RESUMO

Early and sensitive detection of tobacco mosaic virus (TMV) is of great significance for improving crop yield and protecting germplasm resources. Herein, we constructed a novel fluorescence sensor to detect TMV RNA (tRNA) through double strand specific nuclease (DSN) cycle and activator regenerative electron transfer atom transfer radical polymerization (ARGET ATRP) dual signal amplification strategy. The hairpin DNA complementarily paired with tRNA was used as a recognition unit to specifically capture tRNA. By the double-stranded DNA hydrolyzed with DSN, tRNA is released to open more hairpin DNA, and more complementary DNA (cDNA) is bound to the surface of the magnetic beads (MBs) to achieve the first amplification. After binding with the initiator, the cDNA employed ARGET ATRP to attach more fluorescent signal molecules to the surface of MBs, thus achieving the second signal amplification. Under the optimal experimental conditions, the logarithm of fluorescence intensity versus tRNA concentration showed a good linear relationship in the range of 0.01-100 pM, with a detection limit of 1.03 fM. The limit of detection (LOD) was calculated according to LOD = 3 N/S. Besides, the sensor showed good reproducibility and stability, which present provided new method for early and highly sensitive detection for plant viruses.


Assuntos
RNA Viral , Vírus do Mosaico do Tabaco , Vírus do Mosaico do Tabaco/genética , Vírus do Mosaico do Tabaco/química , RNA Viral/análise , Fluorescência , Limite de Detecção , Técnicas Biossensoriais/métodos , Corantes Fluorescentes/química , Espectrometria de Fluorescência
3.
Sci Rep ; 14(1): 927, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195724

RESUMO

Cocaine dependence is a serious world-wide public health problem without an FDA-approved pharmacotherapy. We recently designed and discovered a highly efficient long-acting cocaine hydrolase CocH5-Fc(M6). The present study examined the effectiveness and duration of CocH5-Fc(M6) in blocking interoceptive effects of cocaine by performing cocaine discrimination tests in rats, demonstrating that the duration of CocH5-Fc(M6) in blocking cocaine discrimination was dependent on cocaine dose and CocH5-Fc(M6) plasma concentration. Particularly, a dose of 3 mg/kg CocH5-Fc(M6) effectively attenuated discriminative stimulus effects of 10 mg/kg cocaine, cumulative doses of 10 and 32 mg/kg cocaine, and cumulative doses of 10, 32 and 56 mg/kg cocaine by ≥ 20% for 41, 19, and 10 days, and completely blocked the discriminative stimulus effects for 30, 13, and 5 days with corresponding threshold plasma CocH5-Fc(M6) concentrations of 15.9, 72.2, and 221 nM, respectively, under which blood cocaine concentration was negligible. Additionally, based on the data obtained, cocaine discrimination model is more sensitive than the locomotor activity to reveal cocaine effects and that CocH5-Fc(M6) itself has no long-term toxicity regarding behavioral activities such as lever pressing and food consumption in rats, further demonstrating that CocH5-Fc(M6) has the desired properties as a promising therapeutic candidate for prevenance of cocaine dependence.


Assuntos
Transtornos Relacionados ao Uso de Cocaína , Cocaína , Animais , Ratos , Transtornos Relacionados ao Uso de Cocaína/tratamento farmacológico , Cocaína/farmacologia , Hidrolases de Éster Carboxílico , Locomoção
4.
Chem Res Toxicol ; 36(12): 2001-2009, 2023 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-38014781

RESUMO

Aromatic amines are a class of carcinogenic compounds present in tobacco smoke that are listed on the U.S. Food and Drug Administration (FDA) list of harmful and potentially harmful constituents (HPHCs) in tobacco products and tobacco smoke. The yields of six aromatic amines (1-aminonaphthalene [1-AN], 2-aminonaphthalene [2-AN], 3-aminobiphenyl [3-ABP], 4-aminobiphenyl [4-ABP], ortho-toluidine [o-TOL], and o-anisidine [o-ANI]) in the mainstream smoke from 23 commercial filtered cigars, 16 cigarillos, and 11 large cigars were determined using solid-phase microextraction coupled to gas chromatography triple quadrupole mass spectrometry (SPME headspace GC-MS/MS). The commercial cigars were smoked under the Cooperation Centre for Scientific Research Relative to Tobacco (CORESTA) Recommended Method 64 using a linear cigar smoking machine. The aromatic amine yields in the mainstream smoke from 50 commercial cigars show high levels of variation within and between the products. The average yields of the aromatic amines in the filtered cigars, cigarillos, and large cigars were 108, 371, and 623 ng/cigar for o-TOL; 6, 14, and 22 ng/cigar for o-ANI; 65, 114, and 174 ng/cigar for 1-AN; 25, 59, and 87 ng/cigar for 2-AN; 6, 17, and 27 ng/cigar for 3- ABP; and 8, 11, and 17 ng/cigar for 4-ABP, respectively. The relationships between aromatic amines and (1) total particulate matter (TPM), (2) water-soluble proteins, and (3) water-insoluble proteins were evaluated. We found that the aromatic amines showed a good linear response with TPM on a per cigar basis and showed significant positive correlations with proteins. In addition, the water-insoluble proteins make a greater contribution to the formation of aromatic amines compared to the water-soluble proteins.


Assuntos
Produtos do Tabaco , Poluição por Fumaça de Tabaco , Aminas/química , Fumaça/análise , Espectrometria de Massas em Tandem/métodos , Produtos do Tabaco/análise , Poluição por Fumaça de Tabaco/análise , Água
5.
Opt Express ; 31(20): 33719-33731, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37859145

RESUMO

Large aperture ground-based segmented telescopes typically use electrical edge sensors to detect co-phase errors. However, complex observing environments can lead to zero-point drift of the edge sensors, making it challenging to maintain the long-term co-phase of the segmented primary mirror using only edge sensors. Therefore, employing optical piston error detection methods for short-term calibration of edge sensors can address the issue of zero-point drift in the sensors. However, atmospheric turbulence can affect calibration accuracy based on the observational target. To achieve high-precision calibration of electrical edge sensors, this study investigates the impact of atmospheric turbulence on optical piston error detection. Based on simulated results, it is found that the actual measured piston error in the presence of atmospheric turbulence is the difference between the average phases of the two segments. Subsequently, optical piston error detection experiments were conducted in a segmented mirror system under simulated turbulent conditions with varying turbulence intensities. Experimental studies have shown that the detection accuracy of the optical method is almost the same as without turbulence when using a detection aperture size that is 0.82 times the atmospheric coherence length and an exposure time of at least 40 ms. The root mean square of the cross-calibration is better than 3 nm. These experimental results indicate that under conditions of good atmospheric seeing, the optical piston error detection method can meet the short-term calibration requirements of edge sensors by setting reasonable detection area size and exposure time. It may even be possible to directly use optical detection methods to replace edge sensors for real-time detection of piston errors.

6.
Zootaxa ; 5239(4): 578-584, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-37045080

RESUMO

A new species, Dascillus emarginatus sp. nov., from Shennongjia Nature Reserve, Hubei, China is described. The new species is very similar to D. attenuatus Jin, Xie & Zhu, 2017, from which it can be distinguished by the greater body length, scutellar shield emarginate anteriorly, abdominal ventrites with glabrous spots on each side in both genders, apex of female ventrite 5 emarginate in the middle, and the shape of genitalia. The illustrations of the morphological characters and a distribution map are given.


Assuntos
Besouros , Feminino , Animais , Masculino , Besouros/anatomia & histologia , Distribuição Animal , China
7.
J Periodontal Implant Sci ; 53(5): 347-361, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36919005

RESUMO

PURPOSE: Exosomes are membrane vesicles that are present in body fluids and contain proteins, lipids, and microRNA (miRNA). Periodontal tissue examinations assess the degree of periodontal tissue destruction according to the probing depth (PD), clinical attachment loss (CAL), bleeding on probing, and X-ray examinations. However, the accurate evaluation of the prognosis of periodontitis is limited. In this study, we collected saliva from patients before and after initial periodontal therapy (IPT) and compared changes in the clinical parameters of periodontitis with changes in the components of salivary exosomes. METHODS: Saliva was collected from patients with stage III and IV periodontitis at the first visit and post-IPT. Exosomes were purified from the saliva, and total protein and RNA were extracted. Changes in expression levels of C6, CD81, TSG101, HSP70, and 6 kinds of miRNA were analyzed by western blots and real-time polymerase chain reaction. RESULTS: Patients with increased C6 expression after IPT had significantly higher levels of periodontal inflamed surface area (PISA), miR-142, and miR-144 before and after IPT than patients with decreased C6 expression after IPT. Patients with decreased and unchanged CD81 expression after IPT showed significantly higher PD, CAL, and PISA before IPT than after IPT. Patients with decreased and unchanged TSG101 expression after IPT had significantly higher PD before IPT than after IPT. Patients with increased HSP70 expression after IPT had significantly higher PD and PISA before and after IPT than patients with unchanged HSP70 after IPT. The expression levels of miR-142, miR-144, miR-200b, and miR-223 changed with changes in the levels of C6, CD81, TSG101, and HSP70 in the salivary exosomes of periodontitis patients before and after IPT. CONCLUSIONS: The expression levels of proteins and miRNAs in salivary exosomes significantly changed after IPT in periodontitis patients, suggesting that the components of exosomes could serve as biomarkers for periodontitis.

8.
Talanta ; 257: 124360, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36801566

RESUMO

Plant diseases caused by tobacco mosaic viruses (TMV) reduce the yield and quality of crops and cause significant losses. Early detection and prevention of TMV has important value of research and reality. Herein, a fluorescent biosensor was constructed for highly sensitive detection of TMV RNA (tRNA) based on the principle of base complementary pairing, polysaccharides and atom transfer radical polymerization by electron transfer activated regeneration catalysts (ARGET ATRP) as double signal amplification strategy. The 5'-end sulfhydrylated hairpin capture probe (hDNA) was first immobilized on amino magnetic beads (MBs) by a cross-linking agent, which specifically recognizes tRNA. Then, chitosan binds to BIBB, providing numerous active sites for fluorescent monomer polymerization, which successfully significantly amplifying the fluorescent signal. Under optimal experimental conditions, the proposed fluorescent biosensor for the detection of tRNA has a wide detection range from 0.1 pM to 10 nM (R2 = 0.998) with a limit of detection (LOD) as low as 1.14 fM. In addition, the fluorescent biosensor showed satisfactory applicability for the qualitative and quantitative analysis of tRNA in real samples, thereby demonstrating the potential in the field of viral RNA detection.


Assuntos
Técnicas Biossensoriais , Vírus do Mosaico do Tabaco , RNA , Polissacarídeos , Limite de Detecção
9.
Sci Rep ; 13(1): 640, 2023 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-36635293

RESUMO

Cocaine is a widely abused, hepatotoxic drug without an FDA-approved pharmacotherapy specific for cocaine addiction or overdose. It is recognized as a promising therapeutic strategy to accelerate cocaine metabolism which can convert cocaine to pharmacologically inactive metabolite(s) using an efficient cocaine-metabolizing enzyme. Our previous studies have successfully designed and discovered a highly efficient cocaine hydrolase, denoted as CocH5-Fc(M6), capable of rapidly hydrolyzing cocaine at the benzoyl ester moiety. In the present study, we determined the kinetic parameters of CocH5-Fc(M6) against norcocaine (kcat = 9,210 min-1, KM = 20.9 µM, and kcat/KM = 1.87 × 105 min-1 M-1) and benzoylecgonine (kcat = 158 min-1, KM = 286 µM, and kcat/KM = 5.5 × 105 min-1 M-1) for the first time. Further in vivo studies have demonstrated that CocH5-Fc(M6) can effectively accelerate clearance of not only cocaine, but also norcocaine (known as a cocaine metabolite which is more toxic than cocaine itself) and benzoylecgonine (known as an unfavorable long-lasting metabolite with some long-term toxicity concerns) in rats. Due to the desired high catalytic activity against norcocaine, CocH5-Fc(M6) is capable of quickly detoxifying both cocaine and its more toxic metabolite norcocaine after intraperitoneally administering lethal dose of 60 or 180 mg/kg cocaine. In addition, the ability of CocH5-Fc(M6) to accelerate clearance of benzoylecgonine should also be valuable for the use of CocH5-Fc(M6) in treatment of cocaine use disorder.


Assuntos
Cocaína , Ratos , Animais , Ratos Sprague-Dawley , Hidrólise , Cocaína/metabolismo
10.
Front Plant Sci ; 13: 1083848, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36578339

RESUMO

Banker plant systems increase biological pest control by supporting populations of natural enemies, i.e., using non-pest arthropod species as alternative prey. However, the presence of alternative prey does not always result in improved control of the target pest species owing to the complexity of biotic interactions. To increase the effectiveness of banker plants in IPM programs, a fine understanding of the indirect interactions between target aphid and alternative prey mediated by biocontrol agents is necessary. In this study, we first established a banker plant system, banker plant (Vicia faba)-alternative prey (Megoura japonica)-predator (Harmonia axyridis), to control the target pest (Myzus persicae) on pepper. We found that M. japonica strongly preferred faba bean as a host plant and posed no risk to Solanaceous crops. Harmonia axyridis adults had no significant predation preference for the alternative prey. In the short term, the interaction direction of the two aphid species depended on the relative initial density and the timescale. Harmonia axyridis showed a stronger negative effect on M. persicae than that on M. japonica. In the long term, the presence of alternative prey, M. japonica, enhanced the control effect of H. axyridis to M. persicae with initial density of 100-500 aphids per plant. The presence of the alternative prey could proliferate the population of H. axyridis, with from 0.2- to 2.1-fold increase of H. axyridis eggs. Overall, we put forward a strategy for setting the initial density of alternative prey of the banker plant system to target the high and low density of aphids, which highlighted the importance of indirect interactions in designing a proper banker plant system.

11.
Mitochondrial DNA B Resour ; 7(6): 938-940, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35692657

RESUMO

The White-browed Tit-warbler (Leptopoecile sophiae) is a tiny and infrequently-seen bird species that is mainly distributed in alpine scrub and forests. This species is poorly understood with respect to its natural history and genetic information. In this paper, we first presented the whole mitochondrial genome of the White-browed Tit-warbler. The whole mitochondrial sequence of this species was determined by long-range PCR and conserved primer walking approaches. The results revealed that the whole mitochondrial genome of L. sophiae was 17,803 bp in length with 54.3% A + T content; the genome has the same gene order as that of other passerine birds, including 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and 1 non-coding control region. The control region (D-loop) of L. sophiae was located between tRNA-Gln and tRNA-Phe with 1155 bp length. Phylogenetic analysis indicated that the genome of Leptopoecile species is more closely related to Aegithalos species than to Phylloscopus species. These data provide value for further studies on molecular evolution and conservation genetics on these poorly-known Leptopoecile species at high altitudes.

12.
Insects ; 13(6)2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35735889

RESUMO

Effective biological control agents that can provide sustainable pest control need to be researched in further detail; functional plants (or non-crop insectary plants), in particular, are garnering increased research interest. Much remains to be learned as to how non-crop plants can augment biological control in greenhouse systems. In this study, we combined laboratory and greenhouse assays to assess the extent to which basil (Ocimum basilicum L.) (Lamiales: Lamiaceae) affected the biological control of aphids by the predatory lacewing Chrysopa pallens (Rambur) (Neuroptera: Chrysopidae). In the presence of the target prey (peach aphid; Myzus persicae (Sulzer)), both the vegetative and flowering stages of basil enhanced C. pallens longevity and (early-age) fecundity as compared to a control treatment. When basil plants were established near aphid infested eggplants (Solanum melongena L.), the C. pallens colonization rate improved by 72-92% in the short-term. Lacewing colonization patterns were modulated by the basil planting density and spatial arrangement (i.e., perimeter planting vs. intercropping). Under high density intercrop arrangements, C. pallens colonization rates were highest, its populations persisted longer in the crop, and the aphid numbers declined more rapidly. Our work shows how basil enhanced the key fitness attributes of a generalist predatory lacewing and benefitted aphid biological control in a greenhouse setting.

13.
Bioconjug Chem ; 33(7): 1340-1349, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35767675

RESUMO

It is particularly challenging to develop a truly effective pharmacotherapy for cocaine use disorder (CUD) treatment. Accelerating cocaine metabolism via hydrolysis at cocaine benzoyl ester using an efficient cocaine hydrolase (CocH) is known as a promising pharmacotherapeutic approach to CUD treatment. Preclinical and clinical studies on our first CocH (CocH1), in its human serum albumin-fused form known as TV-1380, have demonstrated the promise of a general concept of CocH-based pharmacotherapy for CUD treatment. However, the biological half-life of TV-1380 (t1/2 = 8 h in rats, associated with t1/2 = 43-77 h in humans) is not long enough for practical treatment of cocaine dependence, which requires enzyme injection for no more than once weekly. Through protein fusion of a human butyrylcholinesterase mutant (denoted as CocH5) with a mutant (denoted as Fc(M6)) of Fc from human IgG1, we have designed, prepared, and tested a new fusion protein (denoted as CocH5-Fc(M6)) for its pharmacokinetic profile and in vivo catalytic activity against (-)-cocaine. CocH5-Fc(M6) represents the currently most efficient long-acting cocaine hydrolase with both the highest catalytic activity against (-)-cocaine and the longest elimination half-life (t1/2 = 229 ± 5 h) in rats. As a result, even at a single modest dose of 3 mg/kg, CocH5-Fc(M6) can significantly and effectively accelerate the metabolism of cocaine in rats for at least 60 days. In addition, ∼70 nM CocH5-Fc(M6) in plasma was able to completely block the toxicity and physiological effects induced by intraperitoneal injection of a lethal dose of cocaine (60 mg/kg).


Assuntos
Transtornos Relacionados ao Uso de Cocaína , Cocaína , Animais , Butirilcolinesterase/genética , Butirilcolinesterase/farmacocinética , Hidrolases de Éster Carboxílico/genética , Cocaína/metabolismo , Cocaína/uso terapêutico , Transtornos Relacionados ao Uso de Cocaína/tratamento farmacológico , Humanos , Ratos , Proteínas Recombinantes
14.
Anal Bioanal Chem ; 414(14): 4227-4234, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35410388

RESUMO

Aromatic amines are a class of carcinogenic compounds in tobacco smoke that are listed on the FDA list of harmful and potentially harmful constituents (HPHCs). A method using solid-phase microextraction-coupled to gas chromatography-triple quadrupole mass spectrometry (SPME headspace GC-MS/MS) was developed and validated for the quantitative determination of six aromatic amines, including 1-aminonaphthalene (1-AN), 2-aminonaphthalene (2-AN), 3-aminobiphenyl (3-ABP), 4-aminobiphenyl (4-ABP), o-toluidine (o-TOL), and o-anisidine (o-ANI), in the mainstream smoke of cigarettes, cigars, and heated tobacco products. The method developed here combines high sensitivity with simple sample preparation and has demonstrated satisfactory linearity for all six aromatic amines with correlation coefficients greater than 0.9994. The limits of detection range and the limits of quantitation range were 12-96 pg/mL and 41-320 pg/mL, respectively. Their recoveries and coefficients of variation (CV%) were 90-112% and 2.1-6.6%, respectively. The new SPME headspace GC/MS/MS method has been successfully applied to measure the contents of the six aromatic amines in the mainstream smoke of cigarettes, cigars, and heated tobacco products.


Assuntos
Fumaça , Produtos do Tabaco , Aminas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Fumaça/análise , Espectrometria de Massas em Tandem/métodos , Nicotiana/química
15.
Pest Manag Sci ; 78(2): 428-437, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34658134

RESUMO

BACKGROUND: Repellent plants (RPs), generally used to keep pests away from crops in integrated pest management, have been shown to reduce the need for synthetic insecticide sprays in various agroecosystems. However, few studies have evaluated the pest control efficiency of RPs over the entire growth period of crops. To evaluate the effect of RPs against Myzus persicae and explore the application and management modes of RPs in the field, we planted mint (Mentha haplocalyx), mung bean (Vigna radiata), celery (Apium graveolens) and coriander (Coriandrum sativum) near the ventilation openings of commercial greenhouses. RESULTS: Five-month sampling results showed that mung bean and mint treatments significantly reduced M. persicae population levels over the entire growth period, whereas celery and coriander reduced aphid infestations during the main harvest period of eggplant. The four RP species showed the strongest repellence during their fast-growth periods. Mung bean and mint shortened the activity period of M. persicae in pepper by delaying the pest in reaching its peak activity. Celery and coriander reduced aphid density on eggplant during their main activity period. Mint, celery and coriander inhibited population growth in M. persicae in the laboratory, revealing the potential value of RPs in reducing M. persicae population levels in the field. CONCLUSION: Mint, mung bean, celery and coriander planted near ventilation openings could be used to control M. persicae infestations in commercial greenhouses. Early planting and timely replanting of RPs is a more effective, environmentally friendly and suitable method for organic pest control compared with chemical pesticides. © 2021 Society of Chemical Industry.


Assuntos
Afídeos , Capsicum , Controle Biológico de Vetores , Solanum melongena , Animais , Produtos Agrícolas
16.
Front Plant Sci ; 13: 1090559, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36714696

RESUMO

Herbivore induced plant volatiles (HIPVs) are key components of plant-herbivorous-natural enemies communications. Indeed, plants respond to herbivores feeding by releasing HIPVs to attract natural enemies. The present study analyses the effect of HIPVs of Vitex negundo (Lamiaceae), an indigenous plant species in northern China, on the predatory ladybug species Harmonia axyridis. Y-tube olfactometer bioassay showed that H. axyridis adults were significantly attracted by V. negundo infested by the aphid Aphis gossypii. We analyzed and compared volatile profiles between healthy and A. gossypii infested V. negundo, screened out the candidate active HIPVs mediated by A. gossypii which could attract H. axyridis, and tested the olfactory behavior of the candidate active compounds on H. axyridis. The gas chromatography-mass spectrometry analysis showed that five volatile compounds were significantly up-regulated after V. negundo infestation by A. gossypii, and five substances were significantly down-regulated in the terpenoid biosynthesis pathway. The olfactory behavior response showed that H. axyridis has significant preference for sclareol, eucalyptol, nonanal and α-terpineol, indicating that this chemical compounds are the important volatiles released by V. negundo to attract H. axyridis. This study preliminarily clarified that V. negundo release HIPVs to attract natural enemies when infected by herbivorous insects. The description of the volatile emission profile enriches the theoretical system of insect-induced volatile-mediated plant defense function of woody plants. Applications in crop protection would lie in designing original strategies to naturally control aphids in orchards.

17.
Insects ; 12(11)2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34821814

RESUMO

Banker plant systems can be used to sustain a reproducing population of biological control agents (BCAs) within a crop, thus providing long-term pest suppression. The founder population of natural enemies in banker plant systems is usually mass-reared on factitious hosts. Thus, a better understanding of the population fitness and pest control performance of mass-reared BCAs in the field is crucial when developing integrated pest management (IPM) strategies. In this study, we determined the fitness of the generalist predator, Chrysopa pallens (Hemiptera: Chrysopidae) ever cultured on different food sources (i.e., mass rearing food, Corcyra cephalonica eggs, and aphid food, Megoura japonica) preying on Aphis craccivora in a banker plant system in a greenhouse based on Chi's age-stage, two-sex life table analysis method. The life tables and predation rate parameters of C. pallens were not significantly different between both treatments under fluctuating temperature conditions. Corcyracephalonica eggs did not significantly weaken the performances of C. pallens in a Vicia faba-A. craccivora banker plant system compared to aphids. In conclusion, C. cephalonica eggs can be used for the mass production of C. pallens as the founder population in a banker plant system. Moreover, linking the life table data with the predation rate is an effective strategy for evaluating mass rearing programs in establishing banker plant systems.

18.
Appl Opt ; 60(24): 7421-7431, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34613031

RESUMO

An 8 m ring aperture segmented telescope is one of the important elements of the Chinese Giant Solar Telescope (CGST) project. In addition, active control of the primary mirror has become a key technology of the 8 wm ring solar telescope (8 m RST). Due to the particularity of the ring aperture, the active maintenance of the segmented RST faces the following problem: edge detection cannot provide enough information to fulfil the closed-loop control. A scheme of using edge and tip detection to complete the active maintenance of an 8 m RST has been proposed. To study the feasibility and performance of edge detection combined with tip detection, we built a workbench of a two-segmented mirror and carried out an active maintenance analysis and experiment. Two capacitive sensors were used to detect the edge height change between the segments, and a Shack-Hartmann sensor was used to detect the tip and tilt change of the segment. A stable mirror figure was achieved during 100 min, and the mirror figure error was maintained at 18.94 nm. This work will provide reference for the implementation of the active control for a segmented ring telescope and also give evidence for the choice of the primary mirror of the CGST.

19.
Macromol Biosci ; 21(8): e2100092, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34008312

RESUMO

Hypoxia as one of the most prominent features in tumors, has presented negative effects on tumor therapies including photodynamic therapy, radiotherapy, and chemotherapies, leading to the tumor regeneration and metastasis. Recently, nanomedicines have been proposed to handle the hypoxia dilemma. Some nanomedicines alleviated hypoxia to enhance the therapeutic effect, others used hypoxia-sensitive substances to treat tumor. Among them, macromolecular nanomaterials-based nanomedicine has attracted increased research interest. However, the complicated tumor microenvironment disturbs the practical application of macromolecular nanomaterials to deal with hypoxia. This review highlights the influence of hypoxia on tumor therapy and some new strategies of using macromolecular nanomaterials to overcome hypoxia for effective tumor therapy.


Assuntos
Nanopartículas , Nanoestruturas , Neoplasias , Fotoquimioterapia , Humanos , Nanomedicina , Nanoestruturas/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Hipóxia Tumoral , Microambiente Tumoral
20.
ACS Chem Neurosci ; 12(1): 184-194, 2021 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-33356138

RESUMO

Opioid drug use, especially heroin, is known as a growing national crisis in America. Heroin itself is a prodrug and is converted to the most active metabolite 6-monoacetylmorphine (6-MAM) responsible for the acute toxicity of heroin and then to a relatively less-active metabolite morphine responsible for the long-term toxicity of heroin. Monoclonal antibodies (mAbs) are recognized as a potentially promising therapeutic approach in the treatment of opioid use disorders (OUDs). Due to the intrinsic challenges of discovering an mAb against multiple ligands, here we describe a general, systematic structure-based virtual screening and design approach which has been used to identify a known anti-morphine antibody 9B1 and a humanized antibody h9B1 capable of binding to multiple addictive opioids (including 6-MAM, morphine, heroin, and hydrocodone) without significant binding with currently available OUD treatment agents naloxone, naltrexone, and buprenorphine. The humanized antibody may serve as a promising candidate for the treatment of OUDs. The experimental binding affinities reasonably correlate with the computationally predicted binding free energies. The experimental activity data strongly support the computational predictions, suggesting that the systematic structure-based virtual screening and humanization design protocol is reliable. The general, systematic structure-based virtual screening and design approach will be useful for many other antibody selection and design efforts in the future.


Assuntos
Naloxona , Naltrexona , Analgésicos Opioides , Heroína , Morfina
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA