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1.
Halyomorpha halys, commonly known as the brown marmorated stink bug, has been recorded for the first time from the Maltese Islands. The record is currently based on the capture of a single specimen. Information is provided on the distribution range of this polyphagous species which was accidentally introduced into Europe (Switzerland) in 2007 and since then has invaded many European countries. Morphological details are also included to aid in the discrimination of this species from similar species occurring in the Mediterranean region. Notes are provided on the feeding strategies used by this insect and the type of damage incurred on agricultural commodities, which are often rendered unsaleable. 相似文献
2.
Ana E. González-Santiago Belinda Vargas-Guerrero Pedro M. García-López Alma L. Martínez-Ayala José A. Domínguez-Rosales Carmen M. Gurrola-Díaz 《Plant foods for human nutrition (Dordrecht, Netherlands)》2017,72(2):134-140
Lupinus albus seeds contain conglutin gamma (Cγ) protein, which exerts a hypoglycemic effect and positively modifies proteins involved in glucose homeostasis. Cγ could potentially be used to manage patients with impaired glucose metabolism, but there remains a need to evaluate its effects on hepatic glucose production. The present study aimed to analyze G6pc, Fbp1, and Pck1 gene expressions in two experimental animal models of impaired glucose metabolism. We also evaluated hepatic and renal tissue integrity following Cγ treatment. To generate an insulin resistance model, male Wistar rats were provided 30% sucrose solution ad libitum for 20 weeks. To generate a type 2 diabetes model (STZ), five-day-old rats were intraperitoneally injected with streptozotocin (150 mg/kg). Each animal model was randomized into three subgroups that received the following oral treatments daily for one week: 0.9% w/v NaCl (vehicle; IR-Ctrl and STZ-Ctrl); metformin 300 mg/kg (IR-Met and STZ-Met); and Cγ 150 mg/kg (IR-Cγ and STZ-Cγ). Biochemical parameters were assessed pre- and post-treatment using colorimetric or enzymatic methods. We also performed histological analysis of hepatic and renal tissue. G6pc, Fbp1, and Pck1 gene expressions were quantified using real-time PCR. No histological changes were observed in any group. Post-treatment G6pc gene expression was decreased in the IR-Cγ and STZ-Cγ groups. Post-treatment Fbp1 and Pck1 gene expressions were reduced in the IR-Cγ group but increased in STZ-Cγ animals. Overall, these findings suggest that Cγ is involved in reducing hepatic glucose production, mainly through G6pc inhibition in impaired glucose metabolism disorders. 相似文献
3.
Sonia A. Soto‐Rodriguez Rodolfo Lozano‐Olvera Daniel A. Palacios‐Gonzalez Carmen Bolan‐Mejia Karla G. Rendon‐Aguilar 《Journal of the World Aquaculture Society》2019,50(5):1002-1015
The phenotypic characteristics and growth kinetics at several temperatures, salinities, and pH values of three Vibrio parahaemolyticus (Vp) strains with different virulence and one nonpathogenic strain were evaluated. Independent of the virulence of the strain, a high metabolic diversity was found, which yielded different colored phenotypes on the CHROMagar? Vibrio. All strains were resistant to ampicillin and carbenicillin, and Vp AHPND+ organisms were the most sensitive to enrofloxacin. The exponential growth of Vp strains started at 1–2 hr of incubation, although no relationship was observed between the bacterial density and degree of virulence. Moreover, the growth of the most virulent strain was independent of the nutrients in the incubation media during the initial hour postinoculation. No strain grew at 4°C in 0% NaCl and pH 4, but only Vp AHPND+ grew at 44°C. For all strains, the lag phase was proportional to the NaCl concentration, and the growth was better at pH 8–9. However, the Vp AHPND? strain displayed a greater variability, was more sensitive to extreme conditions, and showed a lag phase of 9 hr independent of the pH. 相似文献
4.
Mariana J. Ferreyra M. Carmen Menéndez-Sevillano Yanina Noe Luis R. Ibarra Antonio M. De Ron 《Euphytica》2017,213(8):186
In situ conservation of wild species is a method of conservation that allows keeping populations in their natural environments, and set the strategies for maintaining the natural populations. The Active Bank of Northwestern Argentina (BANOA) is in charge of the in situ conservation of wild populations of common bean (Phaseolus vulgaris L.) in Northwestern Argentina (NOA), and has an ex situ collection of 401 landraces and 221 wild accessions from the NOA. We evaluated the phenotypic diversity of 68 common bean wild populations from the NOA both in protected and unprotected areas, finding a moderate variation among them. Ten phenotypic reproductive characteristics related to pod and seed displayed significant differences in the analysis of variance; these traits together with the seed weight were the basis for the multivariate analysis. The cluster analysis ordered the populations in 12 groups but trends in geographical distribution or phenotypical variation were not recognized. For the conservation in situ of the wild bean populations, their diversity should be considered. Two types of populations can be highlighted: (i) candidates for in situ conservation in order to preserve the novel variation generated by convergence with cultivated sympatric germplasm (populations 433, 437, 471, 509, 513 and 517) and (ii) those whose phenotype represents clearly the wild status and should be preserved in situ as such in their current status (populations 480, 495, 496, 525 and 533). 相似文献
5.
Philippe Régnier Jorge Bastias Violeta Rodriguez-Ruiz Noelia Caballero-Casero Carmen Caballo Dolores Sicilia Axelle Fuentes Murielle Maire Michel Crepin Didier Letourneur Virginie Gueguen Soledad Rubio Graciela Pavon-Djavid 《Marine drugs》2015,13(5):2857-2874
Astaxanthin, a powerful antioxidant, is a good candidate for the prevention of intracellular oxidative stress. The aim of the study was to compare the antioxidant activity of astaxanthin present in two natural extracts from Haematococcus pluvialis, a microalgae strain, with that of synthetic astaxanthin. Natural extracts were obtained either by solvent or supercritical extraction methods. UV, HPLC-DAD and (HPLC-(atmospheric pressure chemical ionization (APCI)+)/ion trap-MS) characterizations of both natural extracts showed similar compositions of carotenoids, but different percentages in free astaxanthin and its ester derivatives. The Trolox equivalent antioxidant capacity (TEAC) assay showed that natural extracts containing esters displayed stronger antioxidant activities than free astaxanthin. Their antioxidant capacities to inhibit intracellular oxidative stress were then evaluated on HUVEC cells. The intracellular antioxidant activity in natural extracts was approximately 90-times higher than synthetic astaxanthin (5 µM). No modification, neither in the morphology nor in the viability, of vascular human cells was observed by in vitro biocompatibility study up to 10 µM astaxanthin concentrations. Therefore, these results revealed the therapeutic potential of the natural extracts in vascular human cell protection against oxidative stress without toxicity, which could be exploited in prevention and/or treatment of cardiovascular diseases. 相似文献
6.
A set of primers for analyzing chloroplast DNA diversity in Citrus and related genera 总被引:4,自引:0,他引:4
Chloroplast simple sequence repeat (cpSSR) markers in Citrus were developed and used to analyze chloroplast diversity of Citrus and closely related genera. Fourteen cpSSR primer pairs from the chloroplast genomes of tobacco (Nicotiana tabacum L.) and Arabidopsis were found useful for analyzing the Citrus chloroplast genome (cpDNA) and recoded with the prefix SPCC (SSR Primers for Citrus Chloroplast). Eleven of the 14 primer pairs revealed some degree of polymorphism among 34 genotypes of Citrus, Fortunella, Poncirus and some of their hybrids, with polymorphism information content (PIC) values ranging from 0.057 to 0.732, and 18 haplotypes were identified. The cpSSR data were analyzed with NTSYS-pc software, and the genetic relationships suggested by the unweighted pair group method based on arithmetic means (UPGMA) dendrogram were congruent with previous taxonomic investigations: the results showed that all samples fell into seven major clusters, i.e., Citrus medica L., Poncirus, Fortunella, C. ichangensis Blanco, C. reticulata Swingle, C. aurantifolia (Christm.) Swingle and C. grandis (L.) Osbeck. The results of previous studies combined with our cpSSR analyses revealed that: (1) Calamondin (C. madurensis Swingle) is the result of hybridization between kumquat (Fortunella) and mandarin (C. reticulata), where kumquat acted as the female parent; (2) Ichang papeda (C. ichangensis) has a unique taxonomic status; and (3) although Bendiguangju mandarin (C. reticulata) and Satsuma mandarin (C. reticulata) are similar in fruit shape and leaf morphology, they have different maternal parents. Bendiguangju mandarin has the same cytoplasm as sweet orange (C. sinensis), whereas Satsuma mandarin has the cytoplasm of C. reticulata. Seventeen PCR products from SPCC1 and 21 from SPCC11 were cloned and sequenced. The results revealed that mononucleotide repeats as well as insertions and deletions of small segments of DNA were associated with SPCC1 polymorphism, whereas polymorphism generated by SPCC11 was essentially due to the variation in length of the mononucleotide repeats. 相似文献
7.
8.
We studied photoprotection and antioxidative protection in the three major species of the Canarian laurel forest (Laurus azorica (Seub.) Franco, Persea indica (L.) K. Spreng and Myrica faya Aiton). Trees were exposed to drought under controlled conditions by withholding water until leaf relative water content (RWC) reached 50-55%. Drought reduced photosynthetic rate (P(N)) and was associated with decreased quantum yield of photosystem II (PSII) electron transport and increased non-photochemical quenching (NPQ) in L. azorica and M. faya, but did not increase NPQ in P. indica. Drought-treated trees of L. azorica had the highest de-epoxidation state (DPS) of the xanthophyll cycle and the highest zeaxanthin (Z) concentration, suggesting that this species had more effective photoprotective mechanisms than M. faya and P. indica. Moreover, beta-carotene remained unaltered in L. azorica trees during drought, suggesting that the chloroplasts of this species are better protected against oxidative stress than those of M. faya and P. indica. Increased antioxidation by ascorbate peroxidase, superoxide dismutase and glutathione reductase in L. azorica removed activated oxygen species (AOS) generated during drought treatment. Although M. faya was able to increase its energy dissipation rate by forming Z and thus increasing the DPS of the xanthophyll cycle, it did not respond to drought-induced oxidative stress with the result that beta-carotene degradation occurred. Persea indica did not activate an energy dissipation mechanism in response to drought treatment, hence formation of AOS was likely high in the drought-treated trees. In general, L. azorica was most resistant and P. indica most sensitive to photoinhibition and oxidative stress during drought. 相似文献
9.
The oil of the leaves of Bursera aloexylon was found to contain a high linalool level (96.7 %). The antimicrobial activity tests indicated that the oil was effective against Rhodococcus equi (0.60 mg/ml) and Staphylococcus epidermides (0.15 mg/ml). 相似文献
10.