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991.
Christina A. Olson Karen H. Beard David N. Koons William C. Pitt 《Biological invasions》2012,14(4):889-900
Two nonnative Caribbean frogs, the Puerto Rican coqui and the Cuban greenhouse frog, recently invaded Hawaii. Because of its
louder breeding call, management efforts have focused on the coqui, while little has been done to address the more cryptic
greenhouse frog, even though it may be as widespread and have similar ecological impacts. The goal of this research was to
determine the distribution and detection probability of both species on the island of Hawaii. We conducted a breeding call
presence/absence survey at 446 sites every 2 km along major road networks. We re-surveyed 125 sites twice to determine detection
and occupancy probabilities. Greenhouse frog detection probabilities (0.24, 0.29, 0.48, for each of the three visits, respectively)
were lower than coqui detection probabilities (0.58, 0.73, 0.50, respectively) and increased with visits while those of the
coqui did not. Greenhouse frog detection probabilities were lower in the presence of coquis for the first two surveys (0.12,
0.14) than in sites with greenhouse frogs alone (0.41), while greenhouse frogs had no effect on the detection of coquis. Site
occupancy estimates for the greenhouse and coqui frog were 0.35 and 0.31, respectively, suggesting the species are similarly
widespread. Results suggest multiple visits to sites are required to detect the greenhouse frog. Furthermore, results suggest
that accounting for detectability is essential when determining the extent of invasion of cryptic species. 相似文献
992.
Rb1 and Rg1 are the major ginsenosides in protopanaxadiol and protopanaxatriol. Their content in ginsenosides was 23.8 and 17.6%, respectively.
A total of 22 isolates of β-glucosidase producing microorganisms were isolated from the soil of a ginseng field using Esculin-R2A
agar. Among these isolates, the strain GH21 showed the strongest activities to convert ginsenoside Rb1 and Rg1 to minor ginsenosides compound-K and F1, respectively. Ginsenosides Rb1 and Rg1 bioconversion rates were 74.2 and 89.3%, respectively. Meanwhile, the results demonstrated that the ginsenoside Rg1 could change the biotransformation pathway of ginsenoside Rb1 by inhibiting the formation of the intermediate metabolite gypenoside-XVII. GH21 was identified as a Cladosporium cladosporioides species based on the internal transcribed spacers (ITS) ITS1-5.8S-ITS2 rRNA gene sequences constructed phylogenetic trees. 相似文献
993.
Cho SY Jeong EM Lee JH Kim HJ Lim J Kim CW Shin DM Jeon JH Choi K Kim IG 《Molecules and cells》2012,33(3):235-241
The activation of transglutaminase 2 (TG2), an enzyme that catalyzes post-translational modifications of proteins, has been
implicated in apoptosis, cell adhesion and inflammatory responses. We previously reported that intracellular TG2 is activated
under oxidative stress conditions, such as ultraviolet irradiation, ischemia-reperfusion, and hypoxia. In this study, we examined
the effect of genotoxic stress on the intracellular activity of TG2 using doxorubicin which generates reactive oxygen species
that lead to double-strand breakage of DNA. We demonstrated that doxorubicin elicits the persistent activation of TG2. Doxorubicin-induced
TG2 activity was suppressed by treatment with caffeine at the early phase, N-acetylcysteine at the mid-phase, and EGTA at
the late phase. However, treatment with a blocking antibody against TGFβ or toll-like receptor 2 showed no effect on TG2 activity,
indicating that at least three different signaling pathways may be involved in the process of TG2 activation. In addition,
using MEF cells defective for TG2 and cells overexpressing an activesite mutant of TG2, we revealed that doxorubicin-induced
cell death is inversely correlated with TG2 activity. Our findings indicate that the persistent activation of TG2 by doxorubicin
contributes to cell survival, suggesting that the mechanism-based inhibition of TG2 may be a novel strategy to prevent drug-resistance
in doxorubicin treatment. 相似文献
994.
In this study, loop-mediated isothermal amplification (LAMP)-based molecular marker was developed for authentication of Catharanthus roseus, a medicinal plant. Samples of this plant were collected from different geographical locations in India. Random amplified
polymorphic deoxyribonucleic acid (DNA) analysis of collected samples was carried out with 25 random primers. A 610-bp DNA
fragment, common to all accessions, was eluted, cloned, and sequenced. Four LAMP primers were designed on the basis of sequence
of 610 bp DNA fragment. LAMP reaction, containing 10× Bst DNA polymerase reaction buffer, Bst DNA polymerase, four in-house designed primers, dNTPs, MgSO4, and betaine, was incubated at 65°C for 1 h. The resulting amplicon was visualized by adding SYBR Green I to the reaction
tube. The data showed confirmatory results. Since the assay method is simple, sensitive, and cost-effective, it is a feasible
method for identifying and authentication of C. roseus. 相似文献
995.
冀鲁豫花生育成品种的遗传多样性分析 总被引:2,自引:0,他引:2
以冀鲁豫三省不同地域的41个花生育成品种为材料,利用SSR分子标记结合田间表型鉴定、聚类分析等方法对其遗传多样性进行了研究。结果表明,21对SSR引物对41个花生育成品种进行了扫描,共检测到52个等位变异,每个位点2~4个,平均2.5个,Shannon信息指数变幅为0.21~1.40,平均为0.73,聚类分析显示在阈值为5.54可将供试品种分为3大类群7个亚类。不同品种9个农艺性状变异系数在13.16%~186.49%之间,基于农艺性状的聚类分析结果显示在阈值为5.48时可以将供试品种分为6大类群11个亚类,各大类群间品种的农艺性状表现各具特点。 相似文献
996.
Anirban Guha Debashree Sengupta Girish Kumar Rasineni Attipalli Ramachandra Reddy 《Trees - Structure and Function》2012,26(3):903-918
The present study investigated drought-induced responses of non-enzymatic antioxidants in four diverse mulberry genotypes (Morus indica L. S-36, M-5, MR-2 and V-1). Inside the glasshouse, potted plants were subjected to four water regimes for 75 days: (a) control: pots maintained at 100% pot water holding capacity (PC) (b) low water stress: 75% PC (c) medium water stress: 50% PC and (d) high water stress: 25% PC. Photosynthetic leaf gas exchange and non-enzymatic antioxidants including α-tocopherol, ascorbic acid (AA), glutathione, proline and total carotenoids were measured in leaves at regular intervals. Amongst all, V-1 was relatively drought tolerant and showed exceeded accumulation of α-tocopherol and AA-glutathione pool in association with higher carotenoids and proline contents. Susceptible S-36, M-5 and MR-2 could not induce any significant up-regulation in AA-glutathione pool leading to endogenous loss of α-tocopherol and more lipid peroxidation. Reactive oxygen species (ROS) like hydrogen peroxide (H2O2) and superoxide (O2 · ?) showed apparent accumulation in water-stressed leaves and significantly contributed to lipid peroxidation in susceptible genotypes when compared to V-1. Our study demonstrated that proline, AA and glutathione were the major non-enzymatic antioxidants in mulberry with α-tocopherol and carotenoids as good additional indicators for drought stress tolerance. These non-enzymatic antioxidants can cumulatively render effective protection against oxidative damage and can be considered as reliable markers for screening drought-tolerant mulberry genotypes. 相似文献
997.
Numerous invasive aquatic species introductions can be traced to the aquarium trade. Many potentially harmful aquarium species
may be difficult to identify based on morphology alone. As such, some prohibited or invasive species may be available for
purchase if they are mislabeled as species without restrictions. Here we compare molecular identifications to internet vendors’
identifications for accessions of a popular genus of aquarium plants that are difficult to distinguish morphologically (Myriophyllum; watermilfoils). Specifically, we identified the extensive mislabeling of M. heterophyllum—an invasive species in the northeastern and western US. Furthermore, genotypes of M. heterophyllum found in our aquarium survey have also been found in invasive populations, suggesting their potential introduction through
escape from aquaria, water gardens, or nurseries. Two additional taxa were sold under incorrect names. Finally, our survey
revealed that Myriophyllum taxa present in the aquarium trade generally have poorly known distributions and ecologies, and therefore their invasive
potential is unknown. Our study confirms that molecular identification methods can provide a valuable tool to survey commercial
pathways for potentially harmful species that are otherwise difficult to identify. 相似文献
998.
A wide number of pesticides, including highly persistent organochlorine compounds, such as lindane (γ-Hexachlorocyclohexane),
have deteriorative effect on fauna and flora by inducing oxidative stress. Lindane induces cell damage by producing free radicals
and reactive oxygen species. Quercetin, a dietary flavonoid, is ubiquitous in fruits and vegetables and plays an important
role in human health by virtue of its antioxidant function. In this study the flavonoid quercetin was used to investigate
its antioxidative effect against lindane induced oxidative stress in rats. The level of lipid peroxidation, reduced glutathione
(GSH) were analysed in addition to the antioxidant enzymes such as catalase (CAT), glutathione peroxidase (GPx), superoxide
dismutase (SOD) and glutathione-s-transferase (GST) activities in the liver and kidney tissue. Levels of hepatic marker enzymes
in serum like Aspartate transaminase (AST), Alanine transaminase (ALT), Alkaline phosphatase (ALP) and Lactate dehydrogenase
(LDH) and renal markers like serum creatinine and serum urea were estimated. Administration of Lindane induced histopathological
alterations and increased levels of serum hepatic and renal markers and malondialdehyde (MDA) with a significant decrease
in GSH content and CAT, SOD, GPx and GST activities. Cotreatment of quercetin along with lindane significantly decreased the
lindane induced alteration in histology, serum hepatic and renal markers and MDA and also improved the cellular antioxidant
status. The results show that Quercetin ameliorates Lindane induced oxidative stress in liver and kidney. The quercetin exhibited
chemopreventive effect when administered along with lindane. 相似文献
999.
为了研究睾丸特异性乳酸脱氢酶,即乳酸脱氢酶C4(LDH-C4)基因突变在男性不育发病中的作用,利用LDH-C4特异性底物对100名不明原因男性不育症患者的精子LDH-C4进行活性显色,用变性高效液相色谱(DHPLC)技术对LDH-C4活性低下的患者进行LDHC基因PCR产物的突变筛查,对DHPLC峰形异常的PCR产物进行序列测定.筛选到一组精子LDH-C4活性明显下降的患者,其中1名患者的LDHC基因PCR产物在DHPLC中呈异常洗脱峰.对这一PCR产物进行序列测定,发现患者LDHC基因第5外显子的115位碱基发生了T→A的杂合改变(GenBank登录号GU479375),该突变使LDHC基因的178位密码子由原来的TTG(编码亮氨酸)变为TAG(终止密码子),形成截短的C亚基.T克隆-测序进一步证实了该无义突变的杂合状态.这是在人类LDHC基因上发现的第一个突变,提示LDHC基因突变可能是男性不育发病的原因之一. 相似文献
1000.
一个新水稻温敏感叶色突变体的遗传分析及其基因分子定位 总被引:5,自引:0,他引:5
在粳稻品种嘉花1号(Oryza sativa L. ssp. japonica ‘Jiahua No.1’)种子经60Co γ射线辐照处理的后代中, 发现了1个低温敏感叶色突变体mr21。在较低温度(<25.0°C)条件下, 该突变体幼苗叶色呈黄色; 随着温度逐渐升高, 叶色由黄转绿,其临界温度约为27.5°C; 在低温条件下, 突变体幼苗总叶绿素含量以及叶绿素a、b的含量均较野生型嘉花1号明显下降, 表明该突变体的叶色性状具有明显的温敏感性。遗传分析表明, 该突变体叶色性状受1对隐性核基因控制, 暂将该突变基因命名为thermo-sensitive leaf-color 1(tsl-1)。以该突变体与籼稻9311(Oryza sativa L. ssp. indica ‘9311’)杂交的F2代分离群体作为定位群体, 利用SSR分子标记将tsl-1基因初步定位在水稻(Oryza sativa)第1号染色体短臂上的MM1799与RM8132分子标记之间, 其遗传距离分别为2.4 cM和3.0 cM; 然后, 进一步利用扩大F2代群体及新发展的分子标记将tsl-1基因定位在分子标记InDel2与InDel4之间的198 kb内。研究结果为今后对该基因的克隆和功能分析奠定了基础。 相似文献