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941.
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
942.
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
943.
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
944.
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
945.
Cobalt determinations in biological fluids are of great interest in biological or toxicological research programs. Cobalturia
is often chosen as an indicator for a biological monitoring program in occupational exposure to cobalt dusts. The method described
here derives from the IUPAC reference method for nickel determination. It enables cobaltemia and cobalturia to be measured
in small samples (1 mL). The mean usual values for cobalt in biological fluids are very low (2.7 nmol L−1 for serum and 6.7 nmol L−1 for urine), and therefore, thus require an analytical procedure with preconcentration and extraction. The sample is mineralized
by wet acid digestion. After digestion, inorganic cobalt is extracted in form of ammonium pyrrolidine dithiocarbamate complex
into isobutyl methyl ketone and measured in the organic layer by electrothermal atomic absorption spectrometry.
The analytical parameters are described in detail. The extraction output is about 99%. The detection limits are 1.93 and 1.89
nmol L−1 for serum and urine, respectively. Sensitivity (expressed as the concentration that gives a 0.044 absorbance) is 3.4 nmol
L−1 for serum and 3.3 nmol L−1 for urine.
Within-run precision ranged between 3.9 and 2.5% (coefficients of variation) for serum and 4.2 and 1.1% for urine, at 87 and
136 nmol L−1 levels, respectively. Between-run precision ranged between 4.3 and 3.3% (coefficients of variation) for serum and 4.2 and
2.3% for urine, at 87 and 136 nmol L−1 levels, respectively. At very low concentration, 5.7 nmol L−1 for serum and 2.5 nmol L−1 for urine, the between-run precision is, respectively, 19.5 and 28%.
Linearity is effective between 0 and 272 nmol L−1. Interferences and matrix effects are negligible for urine, serum, or plasma samples without hemoglobin. The method is easily
applicable for routine determinations. 相似文献
946.
947.
During early pregnancy in the rat, focal adhesions disassemble in uterine luminal epithelial cells at the time of implantation
to facilitate their removal so that the implanting blastocyst can invade into the underlying endometrial decidual cells. This
study investigated the effect of ovarian hormones on the distribution and protein expression of two focal adhesion proteins,
talin and paxillin, in rat uterine luminal and glandular epithelial cells under various hormone regimes. Talin and paxillin
showed a major distributional change between different hormone regimes. Talin and paxillin were highly concentrated along
the basal cell surface of uterine luminal epithelial cells in response to oestrogen treatment. However, this prominent staining
of talin and paxillin was absent and also a corresponding reduction of paxillin expression was demonstrated in response to
progesterone alone or progesterone in combination with oestrogen, which is also observed at the time of implantation. In contrast,
the distribution of talin and paxillin in uterine glandular epithelial cells was localised on the basal cell surface and remained
unchanged in all hormone regimes. Thus, not all focal adhesions are hormonally dependent in the rat uterus; however, the dynamics
of focal adhesion in uterine luminal epithelial cells is tightly regulated by ovarian hormones. In particular, focal adhesion
disassembly in uterine luminal epithelial cells, a key component to establish successful implantation, is predominantly under
the influence of progesterone. 相似文献
948.
Marwen Moussa Vincent Espinasse Jean-Marie Perrier-Cornet Patrick Gervais 《Applied microbiology and biotechnology》2009,85(1):165-174
We investigated the influence of cell hydration on the ability of Saccharomyces cerevisiae CBS 1171 to withstand extreme hydrostatic pressure in order to determine the mechanisms involved in cell resistance. Hydration
conditions were modified in two different ways. We first modulated the chemical potential of water by adding glycerol in cell
suspensions. Another procedure consisted in dehydrating cells aerobically and immersing them in perfluorooctane, an innocuous
hydrophobic liquid used as a pressure-transmitting medium, prior to pressure treatments. This original method made it possible
to transmit isostatic pressure to yeast powders without changing the initial water activity (a
w) level at which cells had been equilibrated. The a
w ranged between 0.11 and 0.99. Pressure treatments were applied at levels of up to 600 MPa for 10 min, 24 h, and 6 days. The
dehydration of cells was found to strongly limit, or even prevent, cell inactivation under pressure. Notably, cells suspended
in a water–glycerol mixture with a
w levels of 0.71 or below were completely protected against all pressure treatments. Moreover, cells dehydrated aerobically
survived for 6 days at 600 MPa even when a
w levels were relatively high (up to 0.94). We highlighted the crucial role of water content in determining cellular damage
under pressure. When water is available in a sufficient amount, high pressure induces membrane permeabilization, causing uncontrolled
mass transfers that could lead to death during a prolonged holding under pressure. Possible mechanisms of membrane permeabilization
are discussed. 相似文献
949.
Susumu Goto Yoshiaki Tsuda Yukihiro Koike Chunlan Lian Yuji Ide 《Ecological Research》2009,24(6):1267-1277
To evaluate the effects of landscape and demographic history on genetic variation in Picea glehnii at a regional scale we have investigated the genetic diversity and genetic differentiation of P. glehnii populations in the Furano region, central Hokkaido, Japan, using seven simple sequence repeat (SSR) markers. We found significant
correlations between elevation and genetic diversity parameters. The value of A
[46] increased and the value of F
IS decreased with increasing elevation, while F
IS values were not significantly different from 0 in any of the populations. Significant recent bottlenecks were detected for
isolated populations at low-elevation sites and for relatively large populations at moderate- and high-elevation sites. Evolutionary
events pre-dating the Holocene should be taken into consideration, as elevational gradients should be with respect to locally
adapted traits such as flowering phenology, However, the palynological data from the Holocene in this region suggest that
the distribution pattern of genetic diversity of P. glehnii detected here may have been influenced by past demographic history related to the elevation shifts in this species’ distribution
associated with climate change during this period. Population differentiation was low, with F
ST and G′ST values of 0.022 and 0.065, respectively. However, genetic boundaries were detected around one swamp population (C13). Therefore,
significant isolation by distance (IBD) was not detected when all populations were considered, but there was significant IBD
when the C13 population was excluded. Information on genetic diversity and genetic differentiation at the regional scale may
be useful for selecting seed sources for afforestation programs for P. glehnii. 相似文献
950.
Cervellati C Franzoni L Squerzanti M Bergamini CM Spinozzi F Mariani P Lanzara V Spisni A 《Amino acids》2009,36(4):633-641
Activation of tissue transglutaminase by calcium involves a conformational change which allows exposition of the active site
to the substrate via movements of domains 3 and 4 that lead to an increase of the inter-domain distance. The inhibitor GTP
counteracts these changes. Here we investigate the possible existence of non-native conformational states still compatible
with the enzyme activity produced by chemical and thermal perturbations. The results indicate that chemical denaturation is
reversible at low guanidine concentrations but irreversible at high concentrations of guanidine. Indeed, at low guanidine
concentrations tissue TG-ase exists in a non-native state which is still affected by the ligands as in the native form. In
contrast, thermal unfolding is always irreversible, with aggregation and protein self-crosslinkage in the presence of calcium.
DSC thermograms of the native protein in the absence of ligands consist of two partly overlapped transitions, which weaken
in the presence of calcium and merge together and strengthen in the presence of GTP. Overall, the present work shows, for
the first time, the reversible denaturation of a TG-ase isoenzyme and suggests the possibility that also in in vivo, the enzyme
may acquire non-native conformations relevant to its patho-physiological functions. 相似文献