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171.
J. G. PDUA E. J. OLIVEIRA M. I. ZUCCHI G. C. X. OLIVEIRA L. E. A. CAMARGO M. L. C. VIEIRA 《Molecular ecology resources》2005,5(4):863-865
Passiflora alata is one of the commercialized species of the passion vines, grown for its edible fruits. It is found in South America, mainly Paraguay, Argentina, Peru and Brazil. The development of a set of microsatellite markers was proposed to provide tools for analysing both genetic structure of wild populations and the reproductive system of the species, which are poorly understood. Seven markers were developed from a P. alata‐genomic library enriched for simple sequence repeats (SSR). Twelve individuals were genotyped, and the levels of the expected heterozygosity (HE) did show that those markers could be used to develop P. alata genetic studies. 相似文献
172.
Recently there has been evidence that contaminants other than organophosphate and carbamate pesticides may inhibit the activity of the enzyme acetylcholinesterase (AChE) both under in vitro and in vivo conditions. In this study we investigated the in vitro effect of three detergents \[dodecyl benzyl sulphonate (DBS), sodium dodecyl sulphate (SDS) and a mixture commonly used as domestic detergent (X)] and three metals \[molybdenum, barium and chromium (VI)] on AChE activity of Mytilus galloprovincialis haemolymph. All the detergents tested significantly inhibited the activity of the enzyme. The lowest observed effect concentrations were equal to 12 5 for DBS and 50 mg l-1 for SDS and X. Among the metals, molybdenum and barium had no effect on AChE activity, whereas chromium (VI) significantly depressed the activity of the enzyme at concentrations equal to or higher than 25 mg l-1. These results suggest that the use of AChE as a specific biomarker for organophosphate and carbamate pesticides should be questioned and that the use of this enzyme as a biomarker could be extended. 相似文献
173.
目的:基于钙黄绿素-铜(Ⅱ)荧光体系测定乙酰半胱氨酸。方法:在pH=8.0的Na2HPO.412H2O-KH2PO4缓冲液中,以492 nm为激发波长,520 nm为发射波长测定乙酰半胱氨酸溶液的荧光强度。结果:在pH=8.0的Na2HPO.412H2O-KH2PO4缓冲液中,二价铜离子与钙黄绿素配位引起荧光猝灭。由于乙酰半胱氨酸中巯基上的硫离子与Cu2+的亲和力很强,可从钙黄绿素-铜(Ⅱ)的络合物中夺取铜离子而使钙黄绿素游离出来,从而使体系的荧光得以恢复,并且荧光恢复的程度与加入乙酰半胱氨酸的量在一定范围内成线性。结论:建立了一种测定乙酰半胱氨酸的荧光分析新方法,该方法的线性范围为6.0 10-6~1.4 10-5 mol/L,检出限为4.010-6 mol/L。 相似文献
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175.
Nitric oxide (NO), a vital cell‐signalling molecule, has been reported to regulate toxic metal responses in plants. This work investigated the effects of NO and the relationship between NO and mitogen‐activated protein kinase (MAPK) in Arabidopsis (Arabidopsis thaliana) programmed cell death (PCD) induced by cadmium (Cd2+) exposure. With fluorescence resonance energy transfer (FRET) analysis, caspase‐3‐like protease activation was detected after Cd2+ treatment. This was further confirmed with a caspase‐3 substrate assay. Cd2+‐induced caspase‐3‐like activity was inhibited in the presence of the NO‐specific scavenger 2‐(4‐carboxyphenyl)‐4,4,5,5‐tetramethylimidazoline‐1‐oxyl‐3‐oxide (cPTIO), suggesting that NO mediated caspase‐3‐like protease activation under Cd2+ stress conditions. Pretreatment with cPTIO effectively inhibited Cd2+‐induced MAPK activation, indicating that NO also affected the MAPK pathway. Interestingly, Cd2+‐induced caspase‐3‐like activity was significantly suppressed in the mpk6 mutant, suggesting that MPK6 was required for caspase‐3‐like protease activation. To our knowledge, this is the first demonstration that NO promotes Cd2+‐induced Arabidopsis PCD by promoting MPK6‐mediated caspase‐3‐like activation. 相似文献
176.
177.
LÊDA REGIS 《Invertebrate reproduction & development.》2013,57(3):187-195
The number of eggs produced by Triatoma infestans is determined by the amount of blood ingested; the formation of one egg requires 16 mg blood. An exogenous supply of juvenile hormone, provided by the implantation of extra corpora aliata, increases egg production per unit of blood ingested. The corpus allatum is therefore implicated in the relationship between nutrition and fecundity. The rhythm of egg production is regulated by the nutritional state of the adult female: when the females are fed at frequent intervals, egg production becomes regular and continuous. This calls into question previous interpretations of egg-laying rhythms in the Triatominae as cyclic. 相似文献
178.
Life history strategy of Leptinaria unilamellata (d'Orbigny, 1835) (Mollusca,Pulmonata, Subulinidae)
CAMILLA DE MEDEIROS CARVALHO JAIRO PINHEIRO DA SILVA CRISTIANE LAFETÁ FURTADO MENDONÇA ELISABETH CRISTINA DE ALMEIDA BESSA STHEFANE D'ÁVILA 《Invertebrate reproduction & development.》2013,57(4):211-222
Abstract Life history theory predicts that the patterns of resource allocation in animals are associated with different strategies, selected in the course of evolution. In the present study, the life history of Leptinaria unilamellata was characterized under laboratory conditions. We determined the growth, reproduction, and longevity patterns of this species and elucidated the strategy related to the development of embryos, through direct observations and examination of the morphology of the gravid uterus. Furthermore, we attempted to analyze the glycogen and galactogen contents of the albumen gland, digestive gland and cephalopedal mass in order to understand energy allocation to life history traits, for three life stages. Leptinaria unilamellata's life history is characterized by great longevity, a short juvenile phase, early sexual maturity, and repeated reproductive events, with little reproductive effort at each event and some mortality shortly after the first reproduction. In the terraria, we found juveniles but no eggs. However, the results of the anatomical study showed no morphological connection between the embryos and the parental organism. Thus, this species should be described as ovoviviparous rather than viviparous. Egg retention in the parent organism is the primary cause of the release of juveniles, instead of eggs, enabling the offspring to withstand environmental stress. The higher quantity of galactogen found in the adults' albumen gland, as compared to juveniles and senescent individuals, as well as the ratio of glycogen to galactogen, reveal the allocation of energy to reproduction rather than to growth. The remaining energy is directed to the maintenance of omeostasis. Such pattern was confirmed by the low levels of glycogen and galactogen observed in the senescent stage, compared to the juvenile and adult stages. In the life strategy of L. unilamellata, the distribution of the reproductive effort among many events associated with ovoviviparity indicates a long-term investment in reproductive success. 相似文献
179.
180.
细胞外三磷酸腺苷(extracellular adenosine-5'-triphosphate)是植物细胞的重要信号分子。以烟草悬浮细胞BY-2(Nicotiana tabacum L.cv.Bright Yellow-2)为材料,探讨了胞外三磷酸腺苷对铅胁迫下细胞损伤、H2O2(过氧化氢)含量及H2O2清除酶活性的影响。结果显示,随着Pb(NO3)2浓度的不断提高(30~400 μmol·L-1),细胞外三磷酸腺苷含量呈现出逐渐下降的趋势,但胞内三磷酸腺苷含量及细胞的受损伤程度逐渐增大;同时,H2O2含量和过氧化氢酶的活性均有所上升,并在200 μmol·L-1 Pb(NO3)2处理下达到最大值,而过氧化物酶的活性则不断降低。较之Pb(NO3)2胁迫下的细胞,对Pb(NO3)2胁迫的细胞加入外源三磷酸腺苷使得细胞受损伤程度显著降低,H2O2含量减少,过氧化氢酶活性减弱,而过氧化物酶活性增强。实验结果表明,Pb(NO3)2胁迫诱导的植物细胞损伤和H2O2及其清除酶水平的变化能受到细胞外三磷酸腺苷水平的调节。 相似文献