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11.
A bacteriocin produced by Pseudomonas syringae pv. ciccaronei, used at different purification levels and concentrations in culture and in planta, inhibited the multiplication of P. syringae subsp. savastanoi, the causal agent of olive knot disease, and affected the epiphytic survival of the pathogen on the leaves and twigs of treated olive plants. Treatments with bacteriocin from P. syringae pv. ciccaronei inhibited the formation of overgrowths on olive plants caused by P. syringae subsp. savastanoi strains PVBa229 and PVBa304 inoculated on V-shaped slits and on leaf scars at concentrations of 10(5) and 10(8) CFU ml(-1), respectively. In particular, the application of 6,000 arbitrary units (AU) of crude bacteriocin (dialyzed ammonium sulfate precipitate of culture supernatant) ml(-1) at the inoculated V-shaped slits and leaf scars resulted in the formation of knots with weight values reduced by 81 and 51%, respectively, compared to the control, depending on the strains and inoculation method used. Crude bacteriocin (6,000 AU ml(-1)) was also effective in controlling the multiplication of epiphytic populations of the pathogen. In particular, the bacterial populations recovered after 30 days were at least 350 and 20 times lower than the control populations on twigs and on leaves, respectively. These results suggest that bacteriocin from P. syringae pv. ciccaronei can be used effectively to control the survival of the causal agent of olive knot disease and to prevent its multiplication at inoculation sites.  相似文献   
12.
The aim of this research was to determine whether all memory T cells have the same propensity to migrate to the joint in patients with juvenile idiopathic arthritis. Paired synovial fluid and peripheral blood mononuclear cell proliferative responses to a panel of antigens were measured and the results correlated with a detailed set of laboratory and clinical data from 39 patients with juvenile idiopathic arthritis. Two distinct patterns of proliferative response were found in the majority of patients: a diverse pattern, in which synovial fluid responses were greater than peripheral blood responses for all antigens tested; and a restricted pattern, in which peripheral blood responses to some antigens were more vigorous than those in the synovial fluid compartment. The diverse pattern was generally found in patients with a high acute phase response, whereas patients without elevated acute phase proteins were more likely to demonstrate a restricted pattern. We propose that an association between the synovial fluid T cell repertoire and the acute phase response suggests that proinflammatory cytokines may influence recruitment of memory T cells to an inflammatory site, independent of their antigen specificity. Additionally, increased responses to enteric bacteria and the presence of αEβ7 T cells in synovial fluid may reflect accumulation of gut associated T cells in the synovial compartment, even in the absence of an elevated acute phase response. This is the first report of an association between the acute phase response and the T cell population recruited to an inflammatory site.  相似文献   
13.
Rates and patterns of evolution in partial sequences of five mitochondrial genes (cytochrome b, ATPase 6, NADH dehydrogenase subunit 5, tRNA(Glu), and the control region) were compared among taxa in the passerine bird genera Fringilla and Carduelis. Rates of divergence do not vary significantly among genes, even in comparisons with the control region. Rate variation among lineages is significant only for the control region and NADH dehydrogenase subunit 5, and patterns of variation are consistent with the expectations of neutral theory. Base composition is biased in all genes but is stationary among lineages, and there is evidence for directional mutation pressure only in the control region. Despite these similarities, patterns of substitution differ among genes, consistent with alternative regimes of selective constraint. Rates of nonsynonymous substitution are higher in NADH dehydrogenase subunit 5 than in other protein-coding genes, and transitions exist in elevated proportions relative to transversions. Transitions appear to accumulate linearly with time in tRNA(Glu), and despite exhibiting the highest overall rate of divergence among species, there are no transversional changes in this gene. Finally, for resolving phylogenetic relationships among Fringilla taxa, the combined protein-coding data are broadly similar to those of the control region in terms of phylogenetic informativeness and statistical support.   相似文献   
14.
BiP is found in association with calreticulin, both in the presence and absence of endoplasmic reticulum stress. Although the BiP-calreticulin complex can be disrupted by ATP, several properties suggest that the calreticulin associated with BiP is neither unfolded nor partially or improperly folded. (1) The complex is stable in vivo and does not dissociate during 8 hr of chase. (2) When present in the complex, calreticulin masks epitopes at the C terminus of BiP that are not masked when BiP is bound to an assembly-defective protein. And (3) overproduction of calreticulin does not lead to the recruitment of more BiP into complexes with calreticulin. The BiP-calreticulin complex can be disrupted by low pH but not by divalent cation chelators. When the endoplasmic reticulum retention signal of BiP is removed, complex formation with calreticulin still occurs, and this explains the poor secretion of the truncated molecule. Gel filtration experiments showed that BiP and calreticulin are present in distinct high molecular weight complexes in which both molecules interact with each other. The possible functions of this complex are discussed.  相似文献   
15.

Background  

Recombinant protein production is universally employed as a solution to obtain the milligram to gram quantities of a given protein required for applications as diverse as structural genomics and biopharmaceutical manufacture. Yeast is a well-established recombinant host cell for these purposes. In this study we wanted to investigate whether our respiratory Saccharomyces cerevisiae strain, TM6*, could be used to enhance the productivity of recombinant proteins over that obtained from corresponding wild type, respiro-fermentative strains when cultured under the same laboratory conditions.  相似文献   
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Aims: To evaluate the positive influence of the probiotic strain Lactobacillus paracasei LMGP22043 carried by artichokes into the human gut with special reference to faecal bacterial balance, short‐chain fatty acid concentrations and enzyme activities in a randomized, double‐blind human trial in comparison with probiotic‐free artichokes (control). Methods: Twenty subjects were randomized into two groups, which consumed daily 180 g of the artichoke product (probiotic or control) during two 15‐day study periods (periods 1 and 2) separated by a 15‐day washout in a crossover manner. Faecal samples were subjected to microbiological and biochemical analyses, and a strain‐specific PCR was performed to monitor the probiotic strain. Results: The probiotic strain, transported by the vegetable matrix, transiently colonized the gut of 17/20 subjects (median 6·87 log CFU g?1 faeces), antagonized Escherichia coli and Clostridium spp. and increased the genetic diversity of lactic population based on REP‐PCR profiles, mainly after period 1. Conclusions: The probiotic L. paracasei LMGP22043 successfully colonized the human gut and positively influenced faecal bacteria and biochemical parameters. Significance and Impact of the Study: The association of the probiotic L. paracasei with a food carrier rich in fibre can represent a new strategy for favouring a daily supply of probiotics and attracting more consumers to vegetable food fortified with probiotic strains.  相似文献   
19.

Background

Avoidance of allergens is still recommended as the first and best way to prevent allergic illnesses and their comorbid diseases. Despite a variety of attempts there has been very limited success in the area of environmental control of allergic disease. Our objective was to identify a non-invasive, non-pharmacological method to reduce indoor allergen loads in atopic persons' homes and public environments. We employed a novel in vivo approach to examine the possibility of using aluminum sulfate to control environmental allergens.

Methods

Fifty skin test reactive patients were simultaneously skin tested with conventional test materials and the actions of the protein/glycoprotein modifier, aluminum sulfate. Common allergens, dog, cat, dust mite, Alternaria, and cockroach were used in the study.

Results

Skin test reactivity was significantly reduced by the modifier aluminum sulfate. Our studies demonstrate that the effects of histamine were not affected by the presence of aluminum sulfate. In fact, skin test reactivity was reduced independent of whether aluminum sulfate was present in the allergen test material or removed prior to testing, indicating that the allergens had in some way been inactivated.

Conclusion

Aluminum sulfate was found to reduce the in vivo allergic reaction cascade induced by skin testing with common allergens. The exact mechanism is not clear but appears to involve the alteration of IgE-binding epitopes on the allergen. Our results indicate that it may be possible to diminish the allergenicity of an environment by application of the active agent aluminum sulfate, thus producing environmental control without complete removal of the allergen.  相似文献   
20.
Abstract: Growth periodicity is a phenomenon occurring in fossil and modern corals. The most apparent feature is growth banding, and environmental changes are broadly accepted as controls on this phenomenon. If environment controls the growth, then all corallites within a colony should repeat the same growth pattern, as individuals are clones and must have shared the same environment. A study on several species of Alveolitidae (Anthozoa, Tabulata) from the Late Devonian (Early Frasnian) of the Holy Cross Mountains (Poland) shows that the growth pattern varies between neighbouring individuals within the same corallum. This contradicts observations of closely related Favositida as demonstrated on Pachyfavosites sp. from the Givetian of Avesnois, France, where neighbouring individuals repeat the same pattern. Therefore, environmental control on growth rhythm in Alveolitidae can be excluded; the causes of differences between individuals remain unknown.  相似文献   
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