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91.
Addition of 200 mm of a polyol to anthocyanin containing carrot (Daucus carota L.) cells in suspension culture decreased turgor pressure to zero and induced hyperpolarization of the membrane potential and acidification of the medium due to H+ extrusion. These changes were shown to be slightly affected by vanadate. In parallel, a decrease in intracellular ATP and total adenylate concentrations were observed. However, when the osmoticum was NaCl acidification of the medium occurred in the absence of considerable changes in intracellular ATP concentration. These results are interpreted as indicating that a drop of turgor, by addition of a polyol, triggers a proton extrusion activity which is only slightly inhibited by vanadate but apparently ATP utilizing. The observed decrease in ATP level occurs without a change in respiration rate and is accompanied by a drop in total adenylate pool. However when NaCl is the osmoticum it is assumed that ΔμH+ is enhanced through a Na+/H+ antiporter. The difference between the two types of osmotica as related to their ability to penetrate through the cellular membrane is discussed. 相似文献
92.
Development of Genus/Species-Specific PCR Analysis for Identification of <Emphasis Type="Italic">Carnobacterium</Emphasis> Strains 总被引:6,自引:0,他引:6
Heterofermentative lactic acid bacteria belonging to the genus Carnobacterium are currently divided into seven different species, C. piscicola, C. mobile, C. gallinarum, C. inhibens, C. divergens, C. funditum, and C. alterfunditum. 16S rDNA-targeted PCR assay was carried out for the identification of the genus Carnobacterium. In addition, type strains of all Carnobacterium species were analyzed by 16S–23S rDNA intergenic spacer analysis in comparison with type strains of phylogenetically related
lactic acid bacteria. These methods enabled the identification and the discrimination among Carnobacterium species and the other phylogenetically related lactic acid bacteria. Likewise, analogous results were obtained by restriction
analysis of amplified 16S rDNA performed with HaeIII and HinfI as restriction enzymes.
Received: 25 July 2001 / Accepted: 19 October 2001 相似文献
93.
Anna Lena Lopez Lino Y. Macasaet Michelle Ylade Enrique A. Tayag Mohammad Ali 《PLoS neglected tropical diseases》2015,9(1)
Background
Despite being a cholera-endemic country, data on cholera in the Philippines remain sparse. Knowing the areas where cholera is known to occur and the factors that lead to its occurrence will assist in planning preventive measures and disaster mitigation.Methods
Using sentinel surveillance data, PubMed and ProMED searches covering information from 2008–2013 and event-based surveillance reports from 2010–2013, we assessed the epidemiology of cholera in the Philippines. Using spatial log regression, we assessed the role of water, sanitation and population density on the incidence of cholera.Results and Discussion
We identified 12 articles from ProMED and none from PubMed that reported on cholera in the Philippines from 2008 to 2013. Data from ProMed and surveillance revealed 42,071 suspected and confirmed cholera cases reported from 2008 to 2013, among which only 5,006 were confirmed. 38 (47%) of 81 provinces and metropolitan regions reported at least one confirmed case of cholera and 32 (40%) reported at least one suspected case. The overall case fatality ratio in sentinel sites was 0.62%, but was 2% in outbreaks. All age groups were affected. Using both confirmed and suspected cholera cases, the average annual incidence in 2010–2013 was 9.1 per 100,000 population. Poor access to improved sanitation was consistently associated with higher cholera incidence. Paradoxically, access to improved water sources was associated with higher cholera incidence using both suspected and confirmed cholera data sources. This finding may have been due to the breakdown in the infrastructure and non-chlorination of water supplies, emphasizing the need to maintain public water systems.Conclusion
Our findings confirm that cholera affects a large proportion of the provinces in the country. Identifying areas most at risk for cholera will support the development and implementation of policies to minimize the morbidity and mortality due to this disease. 相似文献94.
MM Barrio R Abes M Colombo G Pizzurro C Boix MP Roberti E Gélizé M Rodriguez-Zubieta J Mordoh JL Teillaud 《PloS one》2012,7(7):e40311
Dendritic cells (DC) can achieve cross-presentation of naturally-occurring
tumor-associated antigens after phagocytosis and processing of dying tumor
cells. They have been used in different clinical settings to vaccinate cancer
patients. We have previously used gamma-irradiated MART-1 expressing melanoma
cells as a source of antigens to vaccinate melanoma patients by injecting
irradiated cells with BCG and GM-CSF or to load immature DC and use them as
a vaccine. Other clinical trials have used IFN-gamma activated macrophage
killer cells (MAK) to treat cancer patients. However, the clinical use of
MAK has been based on their direct tumoricidal activity rather than on their
ability to act as antigen-presenting cells to stimulate an adaptive antitumor
response. Thus, in the present work, we compared the fate of MART-1 after
phagocytosis of gamma-irradiated cells by clinical grade DC or MAK as well
as the ability of these cells to cross present MART-1 to CD8+
T cells. Using a high affinity antibody against MART-1, 2A9, which specifically
stains melanoma tumors, melanoma cell lines and normal melanocytes, the expression
level of MART-1 in melanoma cell lines could be related to their ability to
stimulate IFN-gamma production by a MART-1 specific HLA-A*0201-restricted
CD8+ T cell clone. Confocal microscopy with Alexa Fluor®647-labelled
2A9 also showed that MART-1 could be detected in tumor cells attached and/or
fused to phagocytes and even inside these cells as early as 1 h and up to
24 h or 48 h after initiation of co-cultures between gamma-irradiated melanoma
cells and MAK or DC, respectively. Interestingly, MART-1 was cross-presented
to MART-1 specific T cells by both MAK and DC co-cultured with melanoma gamma-irradiated
cells for different time-points. Thus, naturally occurring MART-1 melanoma
antigen can be taken-up from dying melanoma cells into DC or MAK and both
cell types can induce specific CD8+ T cell cross-presentation
thereafter. 相似文献
95.
Carbon stocks in managed forests of Ontario, Canada, and in harvested wood products originated from these forests were estimated for 2010–2100. Simulations included four future forest harvesting scenarios based on historical harvesting levels (low, average, high, and maximum available) and a no‐harvest scenario. In four harvesting scenarios, forest carbon stocks in Ontario's managed forest were estimated to range from 6202 to 6227 Mt C (millions of tons of carbon) in 2010, and from 6121 to 6428 Mt C by 2100. Inclusion of carbon stored in harvested wood products in use and in landfills changed the projected range in 2100 to 6710–6742 Mt C. For the no‐harvest scenario, forest carbon stocks were projected to change from 6246 Mt C in 2010 to 6680 Mt C in 2100. Spatial variation in projected forest carbon stocks was strongly related to changes in forest age (r = 0.603), but had weak correlation with harvesting rates. For all managed forests in Ontario combined, projected carbon stocks in combined forest and harvested wood products converged to within 2% difference by 2100. The results suggest that harvesting in the boreal forest, if applied within limits of sustainable forest management, will eventually have a relatively small effect on long‐term combined forest and wood products carbon stocks. However, there was a large time lag to approach carbon equality, with more than 90 years with a net reduction in stored carbon in harvested forests plus wood products compared to nonharvested boreal forest which also has low rates of natural disturbance. The eventual near equivalency of carbon stocks in nonharvested forest and forest that is harvested and protected from natural disturbance reflects both the accumulation of carbon in harvested wood products and the relatively young age at which boreal forest stands undergo natural succession in the absence of disturbance. 相似文献
96.
During reticulocyte maturation, hematopoietic progenitors undergo numerous changes to reach the final functional stage which concludes with the release of reticulocytes and erythrocytes into circulation. During this process some proteins, which are not required in the mature stage, are sequestered in the internal vesicles present in multivesicular bodies (MVBs). These small vesicles are known as exosomes because they are released into the extracellular medium by fusion of the MVB with the plasma membrane. Interestingly, during this maturation process some organelles, such as mitochondria and endoplasmic reticulum, are wrapped in double membrane vacuoles and degraded via autophagy. We have demonstrated in human leukemic K562 cells a role for calcium and Rab11 in the biogenesis of MVBs and exosome release. Here we discuss evidence indicating that K562 cells present a high basal level of autophagy, and that there is an association between MVBs and autophagosomes, suggesting a role for the autophagic pathway in the maturation process of this cell type. 相似文献
97.
X-ray crystallographic studies performed on the product of the ketalization reaction of 13beta-ethyl-11alpha-hydroxy-gon-5-ene-3,17-dione have lead to the unequivocal assignment of the 10alpha stereochemistry to C10, showing that an inversion of configuration occurred during formation of the 3,17-diketal. From the Swern oxidation of this compound, 11alpha-(methylthio)methoxy-10alpha-gonene was obtained as the major product instead of the desired 11-ketone. Modeling studies showed that the configurational instability at C10 is determined by the presence of the 11alpha-hydroxyl group. 相似文献
98.
Fanzani A Musarò A Stoppani E Giuliani R Colombo F Preti A Marchesini S 《Biochemical and biophysical research communications》2007,357(1):314-318
Caveolin-3 (Cav-3) is a muscle-specific membrane protein crucial for myoblast differentiation, as loss of the protein due to mutations within the gene causes an autosomal dominant form of limb girdle muscular dystrophy 1-c. Here we show that along with p38 activity the PI3-kinase/AKT/mTOR pathway is required for proper Cav-3 up-regulation during muscle differentiation and hypertrophy, as confirmed by the marked increase of Cav-3 expression in hypertrophied C2C12 cells transfected with an activated form of AKT. Accordingly, Cav-3 expression was further increased during hypertrophy of L6C5 myoblasts treated with Arg(8)-vasopressin and in hypertrophic muscles of MLC/mIGF-1 transgenic mice. In contrast, Cav-3 expression was down-regulated in C2C12 myotubes exposed to atrophic stimuli such as starvation or treatment with dexamethasone. This study clearly suggests that Cav-3 expression is causally linked to the maturation of muscle phenotype and it is tightly regulated by hypertrophic and atrophic stimuli. 相似文献
99.
In seed plant ovules, the diploid maternal sporophytic generation embeds and sustains the haploid generation (the female gametophyte);
thus, two independent generations coexist in a single organ. Many independent studies on Arabidopsis ovule mutants suggest that embryo sac development requires highly synchronized morphogenesis of the maternal sporophyte surrounding
the gametophyte, since megagametogenesis is severely perturbed in most of the known sporophytic ovule development mutants.
Which are the messenger molecules involved in the haploid–diploid dialogue? And furthermore, is this one way communication
or is a feedback cross talk? In this review, we discuss genetic and molecular evidences supporting the presence of a cross
talk between the two generations, starting from the first studies regarding ovule development and ending to the recently sporophytic
identified genes whose expression is strictly controlled by the haploid gametophytic generation. We will mainly focus on Arabidopsis studies since it is the species more widely studied for this aspect. Furthermore, possible candidate molecules involved in
the diploid–haploid generations dialogue will be presented and discussed. 相似文献
100.