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971.
972.
Javier Palazn Rosa M. Cusid Mercedes Bonfill Anna Mallol Elisabet Moyano Carmen Morales M. Teresa Piol 《Plant Physiology and Biochemistry》2003,41(11-12):1019-1025
We tested the effect of the presence in the culture medium of chitosan, vanadyl sulfate or methyl jasmonate on growth and ginsenoside production of three stable hairy root lines of Panax ginseng C.A. Meyer showing different morphological phenotypes C-M, HR-M and T-M. The response depended upon line phenotype, specificity of the elicitor and the stage of growth at which the lines were treated. The highest ginsenoside yield was found when methyl jasmonate was added during the progressive deceleration growth phase (on day 25 of culture). In this case, the ginsenoside content reached at the end of the culture (day 28) by root lines C-M, HR-M and T-M was, respectively, 2, 1.8 and 4 times higher than the highest content achieved, also at the end of the culture, by the corresponding untreated root lines. Under the same conditions, the ginsenoside content in the presence of vanadyl sulfate also increased considerably, while with chitosan it clearly decreased. The ginsenoside pattern in response to the presence of the elicitors is also considered. 相似文献
973.
Laura Zaccaro Enrico Bucci Rosa Maria Vitale Giuseppe Perretta Roberto Fattorusso Ettore Benedetti Michele Saviano Carlo Pedone 《Journal of peptide science》2003,9(2):90-105
The objective of our study was to mimic in a typical reductionist approach the molecular interactions observed at the interface between the gp130 receptor and interleukin-6 during formation of their complex. A peptide system obtained by reproducing some of the interleukin-6/gp130 molecular interactions into a two-helix bundle structure was investigated. The solution conformational features of this system were determined by CD and NMR techniques. The CD titration experiments demonstrated that the interaction between the designed peptides is specific and based on a well-defined stoichiometry. The NMR data confirmed some of the structural features of the binding mechanism as predicted by the rational design and indicated that under our conditions the recognition specificity and affinity can be explained by the formation of a two-helix bundle. Thus, the data reported herein represent a promising indication on how to develop new peptides able to interfere with formation of the interleukin-6/gp130 complex. 相似文献
974.
Prathap Parameswaran César I. Torres Hyung‐Sool Lee Rosa Krajmalnik‐Brown Bruce E. Rittmann 《Biotechnology and bioengineering》2009,103(3):513-523
We demonstrate that the coulombic efficiency (CE) of a microbial electrolytic cell (MEC) fueled with a fermentable substrate, ethanol, depended on the interactions among anode respiring bacteria (ARB) and other groups of micro‐organisms, particularly fermenters and methanogens. When we allowed methanogenesis, we obtained a CE of 60%, and 26% of the electrons were lost as methane. The only methanogenic genus detected by quantitative real‐time PCR was the hydrogenotrophic genus, Methanobacteriales, which presumably consumed all the hydrogen produced during ethanol fermentation (~30% of total electrons). We did not detect acetoclastic methanogenic genera, indicating that acetate‐oxidizing ARB out‐competed acetoclastic methanogens. Current production and methane formation increased in parallel, suggesting a syntrophic interaction between methanogens and acetate‐consuming ARB. When we inhibited methanogenesis with 50 mM 2‐bromoethane sulfonic acid (BES), the CE increased to 84%, and methane was not produced. With no methanogenesis, the electrons from hydrogen were converted to electrical current, either directly by the ARB or channeled to acetate through homo‐acetogenesis. This illustrates the key role of competition among the various H2 scavengers and that, when the hydrogen‐consuming methanogens were present, they out‐competed the other groups. These findings also demonstrate the importance of a three‐way syntrophic relationship among fermenters, acetate‐consuming ARB, and a H2 consumer during the utilization of a fermentable substrate. To obtain high coulombic efficiencies with fermentable substrates in a mixed population, methanogens must be suppressed to promote new interactions at the anode that ultimately channel the electrons from hydrogen to current. Biotechnol. Bioeng. 2009;103: 513–523. © 2009 Wiley Periodicals, Inc. 相似文献
975.
Alfonso Alfaro-Rodríguez Rigoberto Gonzlez-Pia Emilio Arch-Tirado Miriam Carrasco-Portugal Beatríz Prez-Guill Rosa Eugenia Soriano-Rosales Krystell Padilla-Martin Rebeca Uribe-Escamilla Norma Labra-Ruiz 《Chemico-biological interactions》2009,180(3):376-382
The aim of this work was to analyze the effect of carbamazepine (CBZ) on sleep patterns and on “head and body shakes” and to determine the role of serotonin (5-HT) in a model of kainic-induced seizures. Thirty male Wistar rats (280–300 g) were used for polygraphic sleep recording. After a basal recording, the rats were allocated into three groups: kainic acid-treated animals (KA; 10 mg/kg; n = 10), carbamazepine-treated animals (CBZ; 30 mg/kg; n = 10) and animals injected with KA 30 min after pretreatment with CBZ (CBZ + KA; n = 10). Polygraphic recordings were performed for 10 h for 3 days, with the exception of the CBZ group, which were observed for 1 day. In order to measure the head and body shakes that occurred over that time, a behavioral assessment was performed in two additional groups of KA (n = 10) and CBZ + KA (n = 10) animals. After 10 h of behavioral assessment, the rats were sacrificed, and the levels of 5-HT and 5-hydroxy-indol-acetic acid (5-HIAA) were analyzed. We compared these findings with the results from a group of rats without pharmacological intervention (n = 10). All of the recordings were performed from 08:00 to 18:00 h. Data analysis: the electrographic parameters, head and body shake counting and monoamine concentrations were analyzed by an ANOVA test. Differences of *p ≤ 0.01 and **p ≤ 0.001 were considered statistically significant. Our results showed that CBZ exerted a protective effect on sleep pattern alterations induced by KA, which when administered alone caused a complete inhibition of sleep for the first 10 h after administration. Although there was a reduction in the amount of sleep after the administration of KA in CBZ-pretreated animals, sleep inhibition was incomplete. In addition, CBZ decreased the frequency of head and body shakes by 60% as compared to KA. The 5-HT and 5-HIAA levels in the pons were increased in the KA and KA + CBZ groups. Our conclusion is that in addition to decreasing seizure intensity, CBZ facilitates the partial recovery of sleep. These results suggest that CBZ provides neuro-protective effects on sleep and against seizures. 相似文献
976.
Antonella Rosa Giovanni Appendino Monica Deiana Incani Alessandra M. Assunta Dessì 《Chemico-biological interactions》2009,180(2):183-1053
The introduction of an iodine atom on the vanillyl moiety of nonivamide causes a switch in the vanilloid activity (TRPV1 antagonism versus TRPV1 desensitization) and nullifies the aversive properties of capsaicinoids. In the present study we investigated the effect of iodination in the vanillyl moiety on the antioxidant activity of capsaicinoids. To this aim, we have compared the protective effects of nonivamide and three iododerivatives, 2-iodononivamide (2IN), 5-iodononivamide (5IN), and 6-iodononivamide (6IN) in a series of in vitro models of lipid oxidation, namely the autoxidation and the FeCl3-mediated oxidation of linoleic acid at 37 °C and the thermal (140 °C), solvent-free oxidation of cholesterol. All tested compounds could protect linoleic acid and cholesterol against oxidative degradation, the order of potency being: nonivamide > 5IN > 6IN ≈ 2IN. Our results show that, in general, the introduction of an iodine atom on the vanillyl moiety of nonivamide causes a decrease in the antioxidant activity, and this effect is sensitive to the position of iodine on the aromatic ring, with 5IN substantially retaining the efficacy of nonivamide to protect linoleic and cholesterol against free radical attack. Moreover, the pre-treatment with 5IN, at noncytotoxic concentrations, significantly preserved LDL from Cu2+-induced oxidative damage at 37 °C for 2 h, inhibiting the reduction of polyunsaturated fatty acids and cholesterol and the increase of their oxidative products. The results of the present work suggest that 5IN exerts useful antioxidant properties in different in vitro systems of lipid peroxidation. This, coupled to its lacks of pungency and TRPV1 inhibiting properties, qualifies this phenolic compound as an attractive candidate for further investigations in vivo. 相似文献
977.
Rosa Margesin Melanie Jud Dagmar Tscherko & Franz Schinner 《FEMS microbiology ecology》2009,67(2):208-218
Soil samples were collected along two slopes (south and north) at subalpine (1500–1900 m, under closed vegetation, up to the forest line) and alpine altitudes (2300–2530, under scattered vegetation, above the forest line) in the Grossglockner mountain area (Austrian central Alps). Soils were analyzed for a number of properties, including physical and chemical soil properties, microbial activity and microbial communities that were investigated using culture-dependent (viable heterotrophic bacteria) and culture-independent methods (phospholipid fatty acid analysis, FISH). Alpine soils were characterized by significantly ( P <0.01) colder climate conditions, i.e. lower mean annual air and soil temperatures, more frost and ice days and higher precipitation, compared with subalpine soils. Microbial activity (soil dehydrogenase activity) decreased with altitude; however, dehydrogenase activity was better adapted to cold in alpine soils compared with subalpine soils, as shown by the lower apparent optimum temperature for activity (30 vs. 37 °C) and the significantly ( P <0.01–0.001) higher relative activity in the low-temperature range. With increasing altitude, i.e. in alpine soils, a significant ( P <0.05–0.01) increase in the relative amount of culturable psychrophilic heterotrophic bacteria, in the relative amount of the fungal population and in the relative amount of Gram-negative bacteria was found, which indicates shifts in microbial community composition with altitude. 相似文献
978.
Stella Maris Romero María Rosa Alberto María Cristina Manca de Nadra Graciela Vaamonde 《Mycotoxin Research》2009,25(3):165-170
The effect of naturally occurring phenolic compounds on Aspergillus carbonarius growth and ochratoxin A (OTA) production was studied. Caffeic acid and the flavonoids, rutin and quercetin, were added to
Czapek Yeast Extract agar at concentrations ranging between 50 and 500 mg/l. All phenolic compounds had a significant influence
on growth rate and lag phase of A. carbonarius at 250 mg/l. The growth was completely inhibited with 500 mg/l. In comparison with the control, a significant decrease in
OTA production was observed with all phenolic compounds. In general, effect on growth was less evident than effect on toxin
production. An inhibitory effect on growth and OTA production, as concentration was increased was observed in all cases. The
response of A. carbonarius to the flavonoids, rutin and quercetin, was similar. The inhibitory effect of these natural phenolic compounds on fungal
growth and OTA production could be an alternative to the use of chemical fungicides. 相似文献
979.
Sara Mora-Vicente Juli Caujapé-Castells Julia Ma Pérez de Paz Rosa Febles-Hernández Juan E. Malo 《Plant Systematics and Evolution》2009,279(1-4):139-149
Oceanic archipelagos are considered hot-spots of biodiversity because they harbor unique biota with a high level of endemicity. However, the endemic biodiversity of oceanic islands is very vulnerable to extinction. In recent decades, intensive exploitation of these territories and human-mediated introduction of alien species have posed unprecedented threats to the long-term survival of the endemic contingent. The very limited population genetic information available until now for the 28 Canarian endemic Echium taxa has hindered the development of conservation strategies for the ca. 25% of them that are under threat. In this paper, we analyze the levels and distribution of genetic isozyme diversity in 23 natural populations of three endangered endemics of restricted distribution (E. acanthocarpum, CR; E. onosmifolium ssp. spectabile, EN; and E. callithyrsum, VU), and two endemics of wide distribution and in principle free of threat (E. decaisnei and E. onosmifolium). Our results reveal high levels of genetic variability in all these taxa that have plausibly been reached despite a predominance of selfing. They also point out a high incidence of inbreeding in the reproductive dynamics of populations and suggest the potential value of hybridisation processes in shaping the genetic makeup of these species. Among-population differentiation, as estimated by Gst, and genetic distances within taxa are low overall, but they do support the current taxonomic separation between the two subspecies of E. onosmifolium and do not furnish evidence that the current status of the endangered species may be attributed to genetic factors. We use the genetic parameters to suggest some guidelines to help implement a conservation strategy of these taxa. 相似文献
980.
Richard J. Thomas Daniel Webber William Sellors Aaron Collinge Andrew Frost Anthony J. Stagg Stephen C. Bailey Pramukh N. Jayasekera Rosa R. Taylor Steve Eley Richard W. Titball 《Aerobiologia》2009,25(2):75-84
Flow-focussing technology was harnessed to enable generation of large droplet aerosols within high-level microbiological containment.
The Collison nebuliser and flow-focussing aerosol generator (FFAG) produced aerosols from distilled water with average mass
median aerodynamic diameters (MMAD) of 4.19 and 11.93 μm, respectively. The medium type [water, phosphate buffered saline
(PBS) or microbiological broth] had minimal effect on the droplet size generated by the FFAG. The FFAG can be modulated to
generate reproducible aerosols with a wide range of MMADs (9–105 μm). The number of particulates (i.e. fluospheres) contained
within the droplets increased as the MMAD increased from 12 to 50 μm. The technology described can be used for the exposure
of small-animal models to large droplet aerosols (>10 μm) and has applications in healthcare, pharmaceutical, agricultural
and biodefence environments. 相似文献