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91.
Hwijong Yi Soondo Bae Jin Kyo Jung Gil‐Hah Kim Yonggyun Kim Youngnam Yoon Yunwoo Jang Tae‐Wook Jung Rameswor Maharjan 《Entomological Research》2019,49(11):483-489
The soybean pod borer, Maruca vitrata is one of the key insect pests of tropical legumes. It damages tender leaf axils, flower buds, flowers and pods by webbing and boring clusters of flowers and pods. In this study, we investigated the survival and life table parameters of M. vitrata on several leguminous crops; soybean (cvs. Daewon, Poongsannamool and Socheongja), azuki bean (cv. Hongeon), mung bean (cv. Sanpo), and cowpea (cv. Jangchae), compared to artificial diet to assess the antibiosis resistance to M. vitrata. The life‐variables of M. vitrata were significantly affected by the tested legume cultivars. None of the larvae fed cowpea cultivar Jangchae survived. The azuki bean cultivar Hongeon and mung bean cultivar Sanpo were found susceptible to M. vitrata, whereas cowpea cultivar Jangchae and soybean cultivar Daewon showed antibiosis resistance to M. vitrata. Further studies should examine the chemicals associated with leguminous crop cultivars and its mechanism to develop a control method against M. vitrata. 相似文献
92.
Insecticidal and antifeeding activities against Plutella xylostella were observed using whole‐plant‐derived Perilla frutescens material. The active ingredient in P. frutescens was identified by spectroscopic analysis as the sesquiterpenoid α‐farnesene, which showed insecticidal activity against third‐instar larva of P. xylostella in a leaf‐dipping bioassay based on 24‐h LD50 values (LD50 = 53.7 ppm). The feeding inhibition rate of α‐farnesene was 82.98% against P. xylostella at 10 ppm, and the antifeeding responses were determined using an oscilloscope to detect electrophysiological responses. The electrophysiological responses of the medial styloconic sensillum (MSS) were approximately 7‐fold more sensitive at 100 ppm than those of the lateral styloconic sensillum (LSS). These results suggest that the insecticidal and antifeeding effect of α‐farnesene, which is a P. frutescens‐derived material, can be used as a potential control agent for P. xylostella. 相似文献
93.
Jilmar A. Murillo Juan F. Gil Yulieth A. Upegui Adriana M. Restrepo Sara M. Robledo Winston Quiñones Fernando Echeverri Aurelio San Martin Horacio F. Olivo Gustavo Escobar 《Bioorganic & medicinal chemistry》2019,27(1):153-160
We describe the in vitro activity of two natural isomeric ent-beyerene diterpenes, several derivatives and synthetic intermediates. Beyerenols 1 and 2 showed EC50 of 4.6?±?9.4 and 5.3?±?9.4?μg/mL against amastigotes of L. (V) brazilensis, with SI of 5.1 and 7.7, respectively. Beyerenol 1 was synthesized from stevioside. In vivo experiments with bereyenols showed cure in 50% of hamsters infected with L. (V) brazilensis topically applied as Cream I (beyerenol 1, 0.81%, w/w) and Cream III (beyerenol 2, 1.96%, w/w). These results suggest that beyerenols are potential candidates for cutaneous leishmaniasis chemotherapy by topical application. In vitro assays of amastigotes of L. (V) brazilensis showed EC50 of 1.1?±?0.1 and 1.3?±?0.04?μg/mL, with SI of 3.1 and 3.5 for hydrazone intermediates 10 and 11, respectively. 相似文献
94.
95.
Basic optical properties of bioinspired peptide nanostructures are deeply modified by thermally mediated refolding of peptide secondary structure from α‐helical to β‐sheet. This conformational transition is followed by the appearance in the β‐sheet structures of a wideband optical absorption and fluorescence in the visible region. We demonstrate that a new biophotonic effect of optical waveguiding recently observed in peptide/protein nanoensembles is a structure‐sensitive bimodal phenomenon. In the primary α‐helical structure input, light propagates via optical transmission window demonstrating conventional passive waveguiding, based on classical optics. In the β‐sheet structure, fluorescent (active) light waveguiding is revealed. The latter can be attributed to completely different physical mechanism of exciton‐polariton propagation, characterized by high effective refractive index, and can be observed in nanoscale fibers below diffraction limit. It has been shown that peptide material requirements for passive and active waveguiding are dissimilar. Original biocompatibility and biodegradability indicate high potential future applications of these bioinspired waveguiding materials in precise photobiomedicine towards advanced highly selective bioimaging, photon diagnostics, and optogenetics. 相似文献
96.
Solforosi L Bellon A Schaller M Cruite JT Abalos GC Williamson RA 《The Journal of biological chemistry》2007,282(10):7465-7471
Direct interaction between endogenous cellular prion protein (PrP(C)) and misfolded, disease-associated (PrP(Sc)) conformers is a key event in prion propagation, which precedes templated conversion of PrP(C) into nascent PrP(Sc) and prion infectivity. Although almost none of the molecular details of this pivotal process are understood, the persistence of individual prion strains suggests that assembly of the prion replicative complex is mechanistically precise. To systematically map defined regions of PrP(C) sequence that bind tightly to PrP(Sc), we have generated a comprehensive panel of over 45 motif-grafted antibodies containing overlapping peptide grafts collectively spanning PrP residues 19-231. Grafted antibody binding experiments, performed under stringent conditions, clearly identified only three distinct and independent high affinity PrP(Sc) recognition motifs. The first of these binding motifs lies at the very N-terminal region of the mature PrP molecule within PrP-(23-33); the second motif lies within PrP-(98-110); and the third is contained within PrP-(136-158). Mutational analyses of these PrP(Sc)-binding regions revealed that reactivity of the 23-33 and 98-110 segments are largely dependent upon the presence of multiple positively charged amino acid residues. These studies yield new insight into critical peptidic components composing one side of the prion replicative interface. 相似文献
97.
Albar JP Corthals GL Gil C James P Jensen ON Palagi PM Penque D;EuPA Education Committee 《Proteomics》2007,7(Z1):90-94
The early transition of knowledge from highly specialised and sophisticated proteomics research to a diverse community in need of know-how is a challenge that requires backing from advanced research centres and groups, and a coordinating body for the dissemination of this knowledge. The European Proteomics Association (EuPA) Education Committee signified this as a priority area when the EuPA was formed, and began its program to coordinate proteomics training and knowledge dissemination in 2006. This report serves as an update of our past activities and an announcement of upcoming events. Over the last year the EuPA Education Committee has coordinated or supported different educational activities including basic and advanced courses, a summer school, workshops and tutorials. A new programme of basic courses dubbed "Teaching the Teachers" has been initiated. These courses reach a larger, Europe wide, audience in a short timeframe, thus improving the opportunities for trainees of elementary proteomics techniques. Another important event has been the merger of the EuPA and HUPO (Human Proteome Organisation) Education Committees into a single one in order to combine ideas and ef for ts that will favour global education in proteomics. 相似文献
98.
A new sensitive and selective detection of Ga3+ by thiophene-based ‘turn-on’ fluorescent chemosensor
We designed a thiophene-based fluorescent chemosensor DHTC ((E)-2-([3,5-dichloro-2-hydroxybenzylidene]amino)thiophene-3-carboxamide) for detecting gallium (Ga3+). DHTC could probe Ga3+ using fluorescence enhancement. The limit of detection for Ga3+ by DHTC was 0.39 μM. The binding mode of DHTC to Ga3+ was determined as a 1:1 ratio from analysis by Job’s plot and electrospray ionization-mass spectrometry (ESI-MS). In addition, DHTC could selectively detect Ga3+ using test kits. The sensing process of Ga3+ by DHTC was presented using ultraviolet–visible light titration, Job’s plot, ESI-MS, 1H nuclear magnetic resonance titration, and density functional theory calculation. 相似文献
99.
Warren W. Burggren Jose F. Mendez-Sanchez Gil Martínez Bautista Emyr Peña Rafael Martínez García Carlos A. Alvarez González 《Journal of fish biology》2019,94(5):732-744
The genus Oreochromis is among the most popular of the tilapiine cichlid tribe for aquaculture. However, their temperature and hypoxia tolerance, if tested at all, is usually tested at temperatures of 20–25°C, rather than at the considerably higher temperatures of 30–35°C typical of tropical aquaculture. We hypothesized that both larvae and adults of the heat and hypoxia-adapted Tabasco-line of the Nile tilapia Oreochromis niloticus would be relatively hypoxia-tolerant. Oxygen consumption rate (), Q10 and aquatic surface respiration (ASR) was measured using closed respirometry at 2 (c. 0.2 g), 30 (c. 2–5 g), 105 c. (10–15 g) and 240 (c. 250 g) days of development, at 25°C, 30°C and 35°C. at 30°C was inversely related to body mass: c. 90 μM O2 g−1/h in larvae down to c. 1 μM O2 g−1/h in young adults. Q10 for was typical for fish over the range 25–35°C of 1.5–2.0. ASR was exhibited by 50% of the fish at pO2 of 15–50 mmHg in a temperature-dependent fashion. However, the largest adults showed notable ASR only when pO2 fell to below 10 mmHg. Remarkably, pcrit for was 12–17 mmHg at 25–30°C and still only 20–25 mmHg across development at 35°C. These values are among the lowest measured for teleost fishes. Noteworthy is that all fish maintain equilibrium, ventilated their gills and showed routine locomotor action for 10–20 min after ceased at near anoxia and when then returned to oxygenated waters, all fish survived, further indicating a remarkable hypoxic tolerance. Remarkably, data assembled for from >30 studies showed a > x2000 difference, which we attribute to calculation or conversion errors. Nonetheless, pcrit was very low for all Oreochromis sp. and lowest in the heat and hypoxia-adapted Tabasco line. 相似文献
100.
J. Eduardo Fajardo Rojan Shrestha Nelson Gil Adam Belsom Silvia N. Crivelli Cezary Czaplewski Krzysztof Fidelis Sergei Grudinin Mikhail Karasikov Agnieszka S. Karczyńska Andriy Kryshtafovych Alexander Leitner Adam Liwo Emilia A. Lubecka Bohdan Monastyrskyy Guillaume Pagès Juri Rappsilber Adam K. Sieradzan Celina Sikorska Esben Trabjerg Andras Fiser 《Proteins》2019,87(12):1283-1297
With the advance of experimental procedures obtaining chemical crosslinking information is becoming a fast and routine practice. Information on crosslinks can greatly enhance the accuracy of protein structure modeling. Here, we review the current state of the art in modeling protein structures with the assistance of experimentally determined chemical crosslinks within the framework of the 13th meeting of Critical Assessment of Structure Prediction approaches. This largest-to-date blind assessment reveals benefits of using data assistance in difficult to model protein structure prediction cases. However, in a broader context, it also suggests that with the unprecedented advance in accuracy to predict contacts in recent years, experimental crosslinks will be useful only if their specificity and accuracy further improved and they are better integrated into computational workflows. 相似文献