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991.
《Saudi Journal of Biological Sciences》2022,29(4):2532-2540
Marine ecosystems are highly dependent on macroalgea in providing food and shelter for aquatic organisms, interacting with many bacteria and mostly producing secondary metabolites of potent therapeutic antibacterial property. Screening of marine microbial secondary metabolites of valuable biotechnological and therapeutical applications are now extensively studied. In this study, Bacillus spp. identified by DNA sequencing and found associated with Turbinaria ornata, was screened and characterized for its cell free supernatant (CFS) possible antimicrobial and antibiofilm applications. Among the 7 microbial isolates tested, CFS greatly affected Bacillus subitilis (12 mm) and inhibited equally the yeast isolates Candida albicans, Candida tropicalis and Candida glabrata (10 mm) and had no or negligible effect on S.aureus, E.coli, P. aeruginosa. As for the CFS antibiofilm activity, no difference was revealed from the positive control. Algal crude extracts (methanol, acetone and aqueous), on the other hand, were similarly tested for their antimicrobial activity against the seven microbial isolates, where highest activity was observed with the aqueous crude extract against Staphylococcus aureus(10 mm) and Pseudomonas aeruginosa (9 mm) compared to the negligible effects of methanol and acetone crude extracts. Chemical analysis was performed to reveal the major constituents of both crude algal extracts and Bacillus spp. CFS. FTIR spectrum of the bacterial CFS indicated the presence of bacteriocin as the major lipopeptide responsible for its biological activity. Whereas, methanol and water crude algal extract GC–MS spectra revealed different chemical groups of various combined therapeutical activity mainly Naphthalene, amino ethane-sulfonic acid, pyrlene, Biotin and mercury chloromethyl correspondingly. Thus, the present study, demonstrated the moderate activity of both crude algal extract and the bacterial CFS, however, further investigations are needed for a better biological activity. 相似文献
992.
Michael J. Devlin Juli A. Goldfein Eva Petkova Huiping Jiang Pamela S. Raizman Sara Wolk Laurel Mayer Janel Carino Dara Bellace Claudia Kamenetz Ilyse Dobrow B. Timothy Walsh 《Obesity (Silver Spring, Md.)》2005,13(6):1077-1088
Objective: Although binge eating disorder is a common and distressing concomitant of obesity, it has not yet been established whether affected individuals presenting to behavioral weight control programs should receive specialized treatments to supplement standard treatment. This study was designed to examine the added benefit of two adjunctive interventions, individual cognitive behavioral therapy (CBT) and fluoxetine, offered in the context of group behavioral weight control treatment. Research Methods and Procedures: One hundred sixteen overweight/obese women and men with binge eating disorder were all assigned to receive a 16‐session group behavioral weight control treatment over 20 weeks. Simultaneously, subjects were randomly assigned to receive CBT + fluoxetine, CBT + placebo, fluoxetine, or placebo in a two‐by‐two factorial design. Outcome measures, assessed at the end of the 16‐session acute treatment phase, included binge frequency, weight, and measures of eating‐related and general psychopathology. Results: Overall, subjects showed substantial improvement in binge eating and both general and eating‐related psychopathology, but little weight loss. Subjects who received individual CBT improved more in binge frequency than did those not receiving CBT (p < 0.001), and binge abstinence was significantly more common in subjects receiving CBT vs. those who did not (62% vs. 33%, p < 0.001). Fluoxetine treatment was associated with greater reduction in depressive symptoms (p < 0.05). The 54 subjects who achieved binge abstinence improved more on all measures than the 62 subjects who did not. In particular, these subjects lost, on average, 6.2 kg compared with a gain of 0.7 kg among non‐abstainers. Discussion: Adjunctive individual CBT results in significant additional binge reduction in obese binge eaters receiving standard behavioral weight control treatment. 相似文献
993.
R. C. Harper 《Plant biosystems》2013,147(3):583-592
The objective of this study was to describe the physiological condition of bare-root pedunculate oak (Quercus robur L.) seedlings at the time of lifting for cold storage or planting in 1996/1997 and 1997/1998. Dormancy intensity and other physiological measurements and field performance were assessed. Heat treatments were used to assess the taproot resistance to stress using root electrolyte leakage, but the results indicated that the plants were least resistant when mostdormant. Root electrolyte leakage and root growth potential were lowest during the deep dormancy stage and increased again as shoot dormancy was released, coinciding with the period that the plants were most resistant to storage stresses. Dry weight fraction of the shoots was a good indicator of storability, but the other measures were less useful. Despite good survival rates, shoot quality was poor for seedlings lifted early (October) or late (April, May) in the lifting season. 相似文献
994.
Nadine Camougrand Bernhard Kadenbach Martine Guérin 《Journal of bioenergetics and biomembranes》1987,19(5):495-503
In the yeastCandida parapsilosis, the proteins encoded by mitochondrial DNA are different in number and size from those ofSaccharomyces cerevisiae. Nevertheless, the purified cytochromec oxidase fromCandida parapsilosis shows kinetic properties similar to those ofSaccharomyces cerevisiae. 相似文献
995.
《Animal : an international journal of animal bioscience》2019,13(11):2501-2509
Adding corn silage (CS) instead of alfalfa hay (AH) to the finely ground starter diet would improve calf performance if feed intake or feed efficiency is increased. We investigated the effects of replacing AH with CS in the starter diet on nutrient intake, digestibility, growth performance, rumen fermentation and selected blood metabolites in Holstein calves. Newborn male calves (n = 30; 3 days of age; 40.2 ± 1.28 kg BW) were assigned randomly to three groups receiving starter diets containing chopped AH (10% dry matter (DM) basis; AH diet), CS (10% DM, CS diet) or their combination (each at 5% level; AHCS diet). The starter diets had the same nutrient composition but differed in DM content (91.2%, 87.5% and 83.8% for AH, AHCS and CS, respectively). The calves were weaned on day 50, and the study continued until day 70. Nutrient intake, BW (at weaning and at the end of the study) and body measurements were not affected by the diet. During the post-weaning period, average daily gain tended to be greater on CS than on AH diet. Feed efficiency was greater in CS than in AH or AHCS calves during the post-weaning period. Digestibility of neutral detergent fiber was greater in AHCS and CS compared with AH during the post-weaning period. Concentration and profile of volatile fatty acids and ruminal fluid pH were not affected by the diet. Replacing AH with CS in the starter diet had no effect on feed intake, growth performance and general health of the calves. These results indicate that AH and CS can be used interchangeably in dairy calf starter diets until 70 days of age, allowing dairy producers more choices in selecting the feed ingredients. 相似文献
996.
997.
M. Zamboni R. Facchinetti F. Armellini E. Turcato I.A. Bergamo Andreis O. Bosello 《Obesity (Silver Spring, Md.)》1997,5(4):332-337
ZAMBONI M, R FACCHINETTI, F ARMELLINI, E TURCATO, IA BERGAMO ANDREIS, O BOSELLO. Effects of visceral fat and weight loss on lipoprotein(a) concentration in subjects with obesity. We studied the relationships between regional body fat distribution and metabolic variables with lipoprotein(a) [Lp(a)] as well as the effects of weight loss on Lp(a) in 25 women and 9 men with obesity. Regional body fat distribution, as evaluated by the use of computed tomography; Lp(a); and fasting glucose, insulin, cholesterol, and triglycerides were analyzed before and after a very low-energy diet. No significant correlations were found between visceral, subcutaneous, and total fat and Lp(a) or between metabolic variables and Lp(a). All anthropometric variables significantly decreased after a very low-energy diet. Fasting glucose, insulin, triglycerides, and cholesterol significantly decreased after a very low-energy diet. No significant changes in Lp(a) concentration after a very low-energy diet were found. The correlation between the initial values of Lp(a) and changes of Lp(a) after a very low-energy diet was slightly significant (ρ=0.33, p<0.06). In conclusion, our study shows that Lp(a) is not influenced by obesity, visceral fat, metabolic variables, or weight loss induced by a very low-energy diet 相似文献
998.
Hardin BD Kelman BJ Brent RL 《Birth defects research. Part A, Clinical and molecular teratology》2005,73(12):931-955
Trichloroethylene (TCE) and dichloroethylene (DCE) are high-volume industrial chemicals frequently found as contaminants in public drinking water supplies. The developmental toxicity of both chemicals has been evaluated in laboratory and epidemiologic studies. It has been suggested that TCE and DCE are specific cardiac teratogens and that drinking water contaminated with them increases the risk of congenital heart defects in exposed human populations. In contrast, other laboratory and epidemiologic studies do not find an increase in developmental effects, either in general or specifically affecting the heart. This laboratory and epidemiologic base was reviewed to evaluate the strengths and weaknesses of the conflicting published reports. We conclude that the weight of experimental and epidemiologic evidence does not support the hypothesis that TCE or DCE is a selective developmental toxicant in general or a cardiac teratogen specifically. 相似文献
999.
Callus cultures of soft spring wheat were subcultured without separation into explants to follow the line one excised embryo–one callus. This approach revealed the following statistical correlations. Within every cultivar of Triticum aestivum L. and within a row of cultivars arranged in ascending order according to the frequency of embryogenic callus formation, positive correlations (at P = 95) were found between the proliferative activity of callus cells and the frequency of embryogenic callus formation. A reliable intraspecies correlation (significant at P = 95) between multiple regenerations of plants from calluses and the tillering trait (bushiness) of donor plants was also found. We assessed the importance of various statistical parameters of callus cultures for preliminary estimation of morphogenesis efficiency at early stages of culturing. Frequencies of callusogenesis and the growth curves for randomly selected calluses turned out to be noninformative characteristics, unless the morphogenetic activity of calluses was taken into account. The following statistical parameters were found to correlate with the morphogenetic capacity of wheat calluses: gradually increasing coefficients of variation in fresh weight of primary calluses, a larger callus size, and higher fresh weight gain in potentially morphogenetic calluses. 相似文献
1000.
BACKGROUND AND AIMS: Allowing for dispersal limitation, a species' geographic distribution should reflect its environmental requirements. Comparisons among closely related species should reveal adaptive differentiation in species characteristics that are consistent with their differences in geographic distribution. This expectation was tested by comparing characteristics of seedlings of spruce species in relation to environmental factors representative of their current natural ranges. METHODS: Seedlings were grown from a total of 34 populations representing eight North American spruce (Picea) species in a controlled environment chamber for 140 d. Traits related to the potential of seedling establishment, including tolerance to stress events (high temperature, desiccation) were evaluated. Correlations were sought between these characteristics and modal values of latitude, aridity and continentality in the geographic range of each species. KEY RESULTS: Many seedling traits changed significantly in response to stress events, but only the response of chlorophyll concentration differed significantly among species. Components of seedling growth were good correlates of species distribution. Seedling relative growth rate (RGR) and specific leaf area (SLA) were positively correlated with latitude, and leaf weight ratio (LWR) negatively correlated with aridity. Seed mass was negatively correlated with latitude. CONCLUSIONS: Relationships found between seedling traits and geographical variation in environmental conditions suggest that factors such as temperature regime, water availability and perhaps litter depth affect species range in North American spruces. Seedling characteristics appear to be elements in a reasonably distinct environmental niche for each spruce species at the continental scale. 相似文献