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141.
Wen Hui Li Wan Zhong Jia Zi Gang Qu Zhi Zhou Xie Jian Xun Luo Hong Yin Xiao Lin Sun Radu Blaga Bao Quan Fu 《The Korean journal of parasitology》2013,51(2):197-201
A total of 16 Taenia multiceps isolates collected from naturally infected sheep or goats in Gansu Province, China were characterized by sequences of mitochondrial cytochrome c oxidase subunit 1 (cox1) gene. The complete cox1 gene was amplified for individual T. multiceps isolates by PCR, ligated to pMD18T vector, and sequenced. Sequence analysis indicated that out of 16 T. multiceps isolates 10 unique cox1 gene sequences of 1,623 bp were obtained with sequence variation of 0.12-0.68%. The results showed that the cox1 gene sequences were highly conserved among the examined T. multiceps isolates. However, they were quite different from those of the other Taenia species. Phylogenetic analysis based on complete cox1 gene sequences revealed that T. multiceps isolates were composed of 3 genotypes and distinguished from the other Taenia species. 相似文献
142.
Danut Cimponeriu Cristian Serafinceanu Pompilia Apostol Mihai Toma Monica Stavarachi Irina Radu Anne M. Craciun Sonia Spandole Panduru Nicolae Lavinia Rusu Oana M. Schiopu Daniela A. Ion 《Central European Journal of Biology》2013,8(7):625-632
Polymorphisms in IL6, ACE and ATR genes are associated with obesity. Torque Teno virus (TTV) seems to be able to interfere with production of some proinflammatory cytokines associated with obesity and related phenotypes. The aim of this study was to test the potential association between obesity, TTV infection and the IL6 G-174C (rs1800795), ACE I/D (rs4646994), AT1R A1166C (rs5186) polymorphisms. The polymorphisms and the presence of TTV were detected in blood samples from 150 obese and 150 normal-weight, healthy subjects using PCR based methods. IL6-174 CC genotype was more frequent in all obese patients (P=0.02) and in patients without TTV infections (P=0.03) than in controls. Obese women had more frequent TTV infections compared with normal-weight women (P=0.046). Obese subjects, regardless of gender (women P=0.03, men P=0.04), and healthy normal-weight men (P<0.01) carriers of AT1R C allele had higher triglycerides levels compared with non-carriers. The frequency of TTV in the control group (70.67%) was similar to data reported in other populations. The present study indicated that IL6-174 CC genotype and TTV infections in women could be associated with the common form of obesity. 相似文献
143.
Jean de Dieu Tamokou Jean Rodolphe Chouna Eva Fischer-Fodor Gabriela Chereches Otilia Barbos Grigore Damian Daniela Benedec Mihaela Duma Alango Pépin Nkeng Efouet Hippolyte Kamdem Wabo Jules Roger Kuiate Augustin Mot Radu Silaghi-Dumitrescu 《PloS one》2013,8(2)
Traditional remedies have a long-standing history in Cameroon and continue to provide useful and applicable tools for treating ailments. Here, the anticancer, antimicrobial and antioxidant activities of ten antioxidant-rich Cameroonian medicinal plants and of some of their isolated compounds are evaluated.The plant extracts were prepared by maceration in organic solvents. Fractionation of plant extract was performed by column chromatography and the structures of isolated compounds (emodin, 3-geranyloxyemodin, 2-geranylemodin) were confirmed spectroscopically. The antioxidant activity (AOA) was determined using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) bleaching method, the trolox equivalent antioxidant capacity (TEAC), and the hemoglobin ascorbate peroxidase activity inhibition (HAPX) assays. The anticancer activity was evaluated against A431 squamous epidermal carcinoma, WM35 melanoma, A2780 ovary carcinoma and cisplatin-resistant A2780cis cells, using a direct colorimetric assay. The total phenolic content in the extracts was determined spectrophotometrically by the Folin–Ciocalteu method. Rumex abyssinicus showed the best AOA among the three assays employed. The AOA of emodin was significantly higher than that of 3-geranyloxyemodin and 2-geranylemodin for both TEAC and HAPX methods. The lowest IC50 values (i.e., highest cytotoxicity) were found for the extracts of Vismia laurentii, Psorospermum febrifugum, Pentadesma butyracea and Ficus asperifolia. The Ficus asperifolia and Psorospermum febrifugum extracts are selective against A2780cis ovary cells, a cell line which is resistant to the standard anticancer drug cisplatin. Emodin is more toxic compared to the whole extract, 3-geranyloxyemodin and 2-geranylemodin. Its selectivity against the platinum-resistant A2780cis cell line is highest. All of the extracts display antimicrobial activity, in some cases comparable to that of gentamycin. 相似文献
144.
Ivan Jarić Mirjana Lenhardt Jan Pallon Mikael Elfman Aleksandar Kalauzi Radu Suciu Gorčin Cvijanović Torbjörn Ebenhard 《Environmental Biology of Fishes》2011,90(2):171-181
Sturgeon populations in the Danube River have experienced severe decline during the last several decades, mostly due to the
poorly regulated fishery, river fragmentation and water pollution. This study focuses on gaining better understanding of sturgeon
life history primarily by addressing the assessment of microelement accumulation in sturgeon pectoral fin rays, especially
of strontium and calcium, as a method that can reveal migration patterns of anadromous sturgeons. Analysis was performed on
pectoral fin samples of three anadromous Danube sturgeon species (beluga, Russian sturgeon and stellate sturgeon) by the use
of a Nuclear Microprobe technique. The most frequent pattern in analyzed samples was represented by a low Sr:Ca ratio in the
innermost annuli, followed by an increased ratio in the middle annuli segment, and often with a decreased ratio in the outermost
annuli. Probability density estimate has revealed three distinguished maxima of the Sr:Ca ratio, 7.08 × 10−3, 8.98 × 10−3 and 9.90 × 10−3, which might correspond, respectively, to fresh, brackish and saltwater. Although the analysis of the Sr:Ca ratio in sturgeon
pectoral fin rays has revealed changes that might indicate probable migration between habitats with different water salinity,
further studies are needed for improvement of this method. This study represents the first analysis of this kind that was
conducted on sturgeon species from the Black Sea basin. 相似文献
145.
146.
Meyer CL Peisker D Courbot M Craciun AR Cazalé AC Desgain D Schat H Clemens S Verbruggen N 《Planta》2011,234(1):83-95
The synthesis of phytochelatins (PC) represents a major metal and metalloid detoxification mechanism in various species. PC
most likely play a role in the distribution and accumulation of Cd and possibly other metals. However, to date, no studies
have investigated the phytochelatin synthase (PCS) genes and their expression in the Cd-hyperaccumulating species. We used functional screens in two yeast species to identify
genes expressed by two Cd hyperaccumulators (Arabidopsis halleri and Thlaspi caerulescens) and involved in cellular Cd tolerance. As a result of these screens, PCS genes were identified for both species. PCS1 was in each case the dominating cDNA isolated. The deduced sequences of AhPCS1 and TcPCS1 are very similar to AtPCS1 and
their identity is particularly high in the proposed catalytic N-terminal domain. We also identified in A. halleri and T. caerulescens orthologues of AtPCS2 that encode functional PCS. As compared to A. halleri and A. thaliana, T. caerulescens showed the lowest PCS expression. Furthermore, concentrations of PC in Cd-treated roots were the highest in A. thaliana, intermediate in A.
halleri and the lowest in T. caerulescens. This mirrors the known capacity of these species to translocate Cd to the shoot, with T. caerulescens being the best translocator. Very low or undetectable concentrations of PC were measured in A. halleri and T. caerulescens shoots, contrary to A. thaliana. These results suggest that extremely efficient alternative Cd sequestration pathways in leaves of Cd hyperaccumulators prevent
activation of PC synthase by Cd2+ ions. 相似文献
147.
Cüneyt Çirak Jolita Radušienė Liudas Ivanauskas Valdimaras Janulis 《Acta Physiologiae Plantarum》2007,29(3):197-203
The genus Hypericum has received considerable interest from scientists, as it contains the variety of structurally diverse natural products which
possess a wide array of biological properties. The present study was conducted to determine ontogenetic and morphogenetic
variation of hypericin, chlorogenic acid and flavonoids, as rutin, hyperoside, apigenin-7-O-glucoside, quercitrin and quercetin content in Hypericum origanifolium growing in Turkey. Wild growing plants were harvested at vegetative, floral budding, full flowering, fresh fruiting and mature
fruiting stages and dissected into stem, leaf and reproductive tissues and assayed for bioactive compounds by HPLC method.
Hypericin, quercetin and quercitrin content in whole plant increased during course of ontogenesis and the highest level was
reached in blooming stage. On the contrary, hyperoside content of whole plant decreased linearly with advancing of development
stages and the highest level was observed at vegetative stage. Plants produced similar amount of chlorogenic acid at all stages
of plant phenology except for mature fruiting at which the amount of this compound was decreased sharply. Among different
tissues, reproductive parts accumulated the highest level of hypericin, quercetin and quercitrin, however, leaves produced
substantially higher amount of chlorogenic acid and hyperoside. Rutin and apigenin-7-O-glucoside were detectable in all tissues only during fruit maturation. The presence and variation of these bioactive substances
in H. origanifolium were reported for the first time. 相似文献
148.
Ojeda NB Grigore D Yanes LL Iliescu R Robertson EB Zhang H Alexander BT 《American journal of physiology. Regulatory, integrative and comparative physiology》2007,292(2):R758-R763
Our laboratory uses a model of intrauterine growth restriction (IUGR) induced by placental insufficiency in the rat to examine the developmental origins of adult disease. In this model only male IUGR offspring remain hypertensive in adulthood, revealing sex-specific differences. The purpose of this study was to determine whether testosterone with participation of the renin-angiotensin system (RAS) contributes to hypertension in adult male IUGR offspring. At 16 wk of age a significant increase in testosterone (346 +/- 34 vs. 189 +/- 12 ng/dl, P < 0.05) was associated with a significant increase in mean arterial pressure (MAP) measured by telemetry in IUGR offspring (147 +/- 1 vs. 125 +/- 1 mmHg, P < 0.05, IUGR vs. control, respectively). Gonadectomy (CTX) at 10 wk of age significantly reduced MAP by 16 wk of age in IUGR offspring (124 +/- 2 mmHg, P < 0.05 vs. intact IUGR) but had no effect in control (125 +/- 2 mmHg). A significant decrease in MAP in intact IUGR (111 +/- 3 mmHg, P < 0.05 vs. untreated intact IUGR) and castrated IUGR (110 +/- 4 mmHg, P < 0.05 vs. untreated CTX IUGR) after treatment with enalapril for 2 wk suggests a role for RAS involvement. However, the decrease in blood pressure in response to enalapril was greater in intact IUGR (Delta36 +/- 1 mmHg, P < 0.05) compared with CTX IUGR (Delta15 +/- 2 mmHg), indicating an enhanced response to RAS blockade in the presence of testosterone. Thus these results suggest that testosterone plays a role in modulating hypertension in adult male IUGR offspring with participation of the RAS. 相似文献
149.
Iliescu R Cucchiarelli VE Yanes LL Iles JW Reckelhoff JF 《American journal of physiology. Regulatory, integrative and comparative physiology》2007,292(2):R731-R735
Men have higher blood pressure than women, and androgens and oxidative stress have been implicated as playing roles in this sexual dimorphism. The spontaneously hypertensive rat (SHR) is an animal model of both androgen- and oxidative stress-mediated hypertension. Therefore, the present studies were performed to test the hypothesis that androgens cause hypertension in SHR in part by stimulating superoxide production via NADPH oxidase. Castration of male SHR reduced blood pressure by 15% and attenuated both basal and NADPH-stimulated superoxide production in kidney cortical homogenates. Expression of p47(phox) and gp91(phox) but not p22(phox) subunits of NADPH oxidase were significantly lower in kidney cortex from castrated males compared with intact males. Moreover, inhibition of NADPH oxidase with apocynin caused approximately 15 mmHg reduction in blood pressure and reduced basal and NADPH-stimulated superoxide production in intact male SHR, but had no effect on blood pressure or superoxide production in castrated males. These data support the hypothesis that androgens cause oxidative stress and thereby increase blood pressure in male SHR via an NADPH oxidase-dependent mechanism. 相似文献
150.
Chang VT Crispin M Aricescu AR Harvey DJ Nettleship JE Fennelly JA Yu C Boles KS Evans EJ Stuart DI Dwek RA Jones EY Owens RJ Davis SJ 《Structure (London, England : 1993)》2007,15(3):267-273
Glycoproteins present special problems for structural genomic analysis because they often require glycosylation in order to fold correctly, whereas their chemical and conformational heterogeneity generally inhibits crystallization. We show that the "glycosylation problem" can be solved by expressing glycoproteins transiently in mammalian cells in the presence of the N-glycosylation processing inhibitors, kifunensine or swainsonine. This allows the correct folding of the glycoproteins, but leaves them sensitive to enzymes, such as endoglycosidase H, that reduce the N-glycans to single residues, enhancing crystallization. Since the scalability of transient mammalian expression is now comparable to that of bacterial systems, this approach should relieve one of the major bottlenecks in structural genomic analysis. 相似文献