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101.
BackgroundFour biopesticide prototypes formulated as dispersible granules and dry powders based on 2 Colombian isolates of Trichoderma koningiopsis (Th003) and T. asperellum (Th034) were developed. These microorganisms have antagonist activity against Fusarium oxysporum f. sp. lycopersici and Rhizoctonia solani with a reduction in incidence of between 70 and 100% in tomato crops and potato crops, respectively.AimTo determine the effect of the formulation on the shelf-life of 4 biopesticides based on T. koningiopsis Th003 and Trichoderma asperellum Th034 at 3 different temperatures.MethodsThe formulation effect was determined by evaluating the germination of unformulated and formulated conidia (dispersible granules and dry powder) stored at 8, 18 and 28 °C for 18 months. Germination kinetics were used to estimate the shelf-life by using different mathematical models (zero order, first order, second order, Higuchi model, Korsmeyer-Peppas model and polynomial model).ResultsThe products showed high stability of the conidia germination when they were stored at 8 and 18° C, with shelf-lives of 14.4 and 13.9 months for dry powder based on Th003, and 12.0 and 10.8 months for dry powder based on Th034, respectively. Prototypes formulated as dispersible granules stored at the same temperatures (8 and 18 °C) showed lower shelf-lives, with values of 11.6 and 10.9 months for the Th003 product, and 10.7 and 7.2 months for the dispersible granules based on Th034. Significant reductions in germination were observed on unformulated conidia at all storage temperatures evaluated.ConclusionsThe formulation type affected the conidia stability of the 2 Trichoderma spp. Colombian isolates. Dry powder was the prototype with the highest stability and shelf-life at all temperatures evaluated. 相似文献
102.
Morsy MA Abdalla AM Mahmoud AM Abdelwahab SA Mahmoud ME 《Journal of physiology and biochemistry》2012,68(1):29-35
Liver fibrosis is a major health problem that can lead to the development of liver cirrhosis and hepatocellular carcinoma.
On the other hand, several antioxidants have been shown to possess protective effect against liver fibrosis. Therefore, in
the present work, the effectiveness of curcumin, α-lipoic acid, and N-acetylcysteine in protecting against carbon tetrachloride (CCl4)-induced liver fibrosis as well as the mechanism(s) implicated in this protective effect was studied. The antioxidants used
in this study resulted in hepatoprotective effect as evident by substantial decreases in collagen deposition in histopathological
examinations in addition to significant decrease in serum levels of alanine aminotransferase, aspartate aminotransferase,
gamma glutamyl transpeptidase, bilirubin, and transforming growth factor-alpha (TGF-α) as well as hepatic malondialdehyde
concentration, with a concurrent increase in serum matrix metalloproteinase-13 (MMP-13) and hepatic reduced glutathione (GSH)
levels as compared to CCl4 fibrotic group. In conclusion, curcumin, α-lipoic acid, and N-acetylcysteine protect rats against CCl4-induced liver fibrosis most possibly through their antioxidant activities and their capacities to induce MMP-13 and to inhibit
TGF-α levels. 相似文献
103.
Magda Roszczynska-Kurasinska Andrzej Nowak Daniel Kamieniarz Sorin Solomon J?rgen Vitting Andersen 《PloS one》2012,7(12)
The dynamics of collective decision making is not yet well understood. Its practical relevance however can be of utmost importance, as experienced by people who lost their fortunes in turbulent moments of financial markets. In this paper we show how spontaneous collective “moods” or “biases” emerge dynamically among human participants playing a trading game in a simple model of the stock market. Applying theory and computer simulations to the experimental data generated by humans, we are able to predict the onset of such moments before they actually happen. 相似文献
104.
105.
D Coggon G Ntani KT Palmer VE Felli R Harari LH Barrero SA Felknor D Gimeno A Cattrell C Serra M Bonzini E Solidaki E Merisalu RR Habib F Sadeghian M Kadir SS Warnakulasuriya K Matsudaira B Nyantumbu MR Sim H Harcombe K Cox MH Marziale LM Sarquis F Harari R Freire N Harari MV Monroy LA Quintana M Rojas EJ Salazar Vega EC Harris S Vargas-Prada JM Martinez G Delclos FG Benavides M Carugno MM Ferrario AC Pesatori L Chatzi P Bitsios M Kogevinas K Oha T Sirk A Sadeghian RJ Peiris-John N Sathiakumar 《PloS one》2012,7(7):e39820
Background
The CUPID (Cultural and Psychosocial Influences on Disability) study was established to explore the hypothesis that common musculoskeletal disorders (MSDs) and associated disability are importantly influenced by culturally determined health beliefs and expectations. This paper describes the methods of data collection and various characteristics of the study sample.Methods/Principal Findings
A standardised questionnaire covering musculoskeletal symptoms, disability and potential risk factors, was used to collect information from 47 samples of nurses, office workers, and other (mostly manual) workers in 18 countries from six continents. In addition, local investigators provided data on economic aspects of employment for each occupational group. Participation exceeded 80% in 33 of the 47 occupational groups, and after pre-specified exclusions, analysis was based on 12,426 subjects (92 to 1018 per occupational group). As expected, there was high usage of computer keyboards by office workers, while nurses had the highest prevalence of heavy manual lifting in all but one country. There was substantial heterogeneity between occupational groups in economic and psychosocial aspects of work; three- to five-fold variation in awareness of someone outside work with musculoskeletal pain; and more than ten-fold variation in the prevalence of adverse health beliefs about back and arm pain, and in awareness of terms such as “repetitive strain injury” (RSI).Conclusions/Significance
The large differences in psychosocial risk factors (including knowledge and beliefs about MSDs) between occupational groups should allow the study hypothesis to be addressed effectively. 相似文献106.
The link between sirtuin activity and mitochondrial biology has recently emerged as an important field. This conserved family of NAD(+)-dependent deacetylase proteins has been described to be particularly involved in metabolism and longevity. Recent studies on protein acetylation have uncovered a high number of acetylated mitochondrial proteins indicating that acetylation/deacetylation processes may be important not only for the regulation of mitochondrial homeostasis but also for metabolic dysfunction in the context of various diseases such as metabolic syndrome/diabetes and cancer. The functional involvement of sirtuins as sensors of the redox/nutritional state of mitochondria and their role in mitochondrial protection against stress are hereby described, suggesting that pharmacological manipulation of sirtuins is a viable strategy against several pathologies. 相似文献
107.
Ran Chen Jinu John Antonina Lavrentieva Susann Müller Magda Tomala Yangxi Zhao Robert Zweigerdt Sascha Beutel Bernd Hitzmann Cornelia Kasper Ulrich Martin Ursula Rinas Frank Stahl Thomas Scheper 《Engineering in Life Science》2012,12(1):29-38
Basic fibroblast growth factor (FGF‐2) is a multifunctional cytokine that regulates various cellular processes both in vitro and in vivo. FGF‐2 is extensively used in embryonic stem cell cultures since it can maintain the cells in an undifferentiated state. However, the high price of FGF‐2 has limited its application in stem cell research. Here we present a fast and efficient process for the purification of FGF‐2 from recombinant Escherichia coli cultures using reusable membrane adsorbers. A high expression level of FGF‐2 (42 mg/g dry cell) was achieved by fed‐batch cultivation of E. coli BL21(DE3). A new combination of cation exchange membrane chromatography and heparin‐sepharose affinity chromatography was used for the purification of the protein. A novel anion exchange membrane chromatography was used in the polishing step to remove endotoxins and DNA. In this new process, about 200 mg soluble FGF‐2 was yielded from 1.9 L culture broth with a purity of 98%. The purified protein was identified to be endotoxin‐free and bioactive. It was successfully tested to keep primate embryonic stem cell and human‐induced pluripotent stem cell pluripotent. Our approach, in which a controlled cultivation process is combined with an optimized fast and versatile downstreaming process, is suitable for low‐cost preparation of bioactive FGF‐2 at bench‐scale and may be beneficial to the effective production of other cytokines. 相似文献
108.
We are responding to a Letter to the Editor addressing the Method section of our paper “Different measures of ‘genome-wide’ DNA methylation exhibit unique properties in placental and somatic tissues.” The letter raised concerns that the protocol for Epigentek’s MethylFlash kit was followed incorrectly based on the wording of an online publication of our article. We admittedly made an error in the language used to describe the MethylFlash protocol in our initial submission and thus this was corrected as soon as it was brought to our attention. However, the error was only in language and not procedure. We are confident that the protocol was followed as stated in the insert provided with the MethylFlashTM Methylated DNA Quantification kit (Colorimetric).We are responding to a Letter to the Editor addressing the Method section of our paper “Different measures of ‘genome-wide’ DNA methylation exhibit unique properties in placental and somatic tissues” (Price ME, Cotton AM, PeÒaherrera MS, McFadden DE, Kobor MS, Robinson WP. Different measures of “genome-wide” DNA methylation exhibit unique properties in placental and somatic tissues. Epigenetics 2012; 7: 652–63; PMID: 22531475; 10.4161/epi.20221). The letter raised concerns that the protocol for Epigentek’s MethylFlash kit was followed incorrectly based on the wording of an online publication of our article. We admittedly made an error in the language used to describe the MethylFlash protocol in our initial submission and thus this was corrected as soon as it was brought to our attention. However, the error was only in language and not procedure. We are confident that the protocol was followed as stated in the insert provided with the MethylFlashTM Methylated DNA Quantification kit (Colorimetric). 相似文献
109.
Cécile Jauzein Yves Collos Esther Garcés Magda Vila Mercedes Maso 《Journal of phycology》2008,44(5):1136-1145
In batch cultures of four Mediterranean strains (from France, Italy, and Spain) of Alexandrium catenella (Whedon et Kof.) Balech growing on a daily light cycle, ammonium and urea uptake were estimated by the 15N tracer technique. Ammonium uptake could be described by Michaelis–Menten kinetics along a substrate gradient of 0.1–10 μgat N · L?1 for the four strains, while two different patterns were observed for urea uptake with Michaelis–Menten kinetics for one strain and linear kinetics for the others. In all cases, an increase in uptake rates with time was noted over the daylight period. This trend led to a net increase in the maximum uptake rate (Vmax; for saturable kinetics) and in the initial slope α. For ammonium, Vmax increased by a factor of 2–10 depending on the strain, and, for urea, the maximal uptake rates measured increased by a factor of 2–18. Temporal variations of half‐saturation constants (Ks) for both nutrients did not show a clear trend. Increases in Vmax and α showed an acclimation of the cells’ uptake system over time to a N pulse, which may be explained by the light periodicity. For two strains, extensive ammonium release was observed during urea assimilation. This mechanism removes urea from the medium, so it is no longer available to other potential competitors, but supplies N back to the medium in the form of ammonium. From a methodological point of view, the phenomenon leads to considerable underestimates of the contribution of urea to phytoplankton growth. 相似文献
110.
Isabel Bravo Magda Vila Mercedes Mas Rosa Isabel Figueroa Isabel Ramilo 《Harmful algae》2008,7(4):515-522
Annual recurrent blooms of the toxic dinoflagellates Alexandrium catenella and Alexandrium minutum were detected from 2000 to 2003 in harbours along the Catalan coast. The interrelation study between the occurrence of the blooms and specific external conditions at the study sites demonstrated that different factors are required for the bloom of each Alexandrium species. Concentrations higher than 105 cells l−1 of A. catenella were only detected in Tarragona harbour. These blooms were associated with water surface temperature between 21 and 25 °C and salinities of around 34 psu or higher than 37 psu. A. minutum appeared widely spread along the Catalan coast, though the most intensive and recurrent blooms of this species were observed in Arenys de Mar harbour. Concentrations of millions of cells per litre of A. minutum were associated with water temperatures below 14 °C and salinities of around 34–36 psu. A. minutum cell densities showed a positive significant correlation with NO3 but a negative correlation with NH4. On the other hand, A. catenella blooms dominated when both NO3 and NH4 levels were high. The prevailing inorganic nitrogen form (NO3 vs. NH4) could explain why these two species rarely coincide in the same harbours. Accumulation of cysts in the sediment was found to be an important potential factor for the recurrence of these species. The 4.3 × 103 A. catenella cysts cm−3 of wet sediment in Tarragona harbour and the 3.02 × 103 A. minutum cysts cm−3 of wet sediment in Vilanova harbour were the highest concentrations observed from the cyst study. Confined waters such as harbours play an important role as reservoirs for the accumulation of cysts and vegetative cells, which contributes to the expansion of these dinoflagellates in the region. However, the particular environmental conditions are also decisive factors of bloom intensity. 相似文献