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141.
We previously described the first reference map for the proteome of one strain of serogroup A Neisseria meningitidis (MenA), a major cause of epidemic meningitis in humans. As a preliminary finding, in that work we noted that 2‐DE protein maps of closely related MenA isolates from different epidemics spreads could be easily compared to detect minor differences and that 2‐DE phenotypes attributable to the well‐known epidemiological marker tbpB agreed with the genoclouds model of MenA epidemiological variation during pandemic waves. We explored here the possibility that an extended comparative study of 2‐DE maps of isolates representative of the nine genoclouds described by Achtman and collaborators could be used to discriminate between strains otherwise undistinguishable. We showed the example of 14 proteins with different 2‐DE spot patterns in different genoclouds that could be considered as putative tracers for alike‐strains discrimination. We introduce the novel concept that comparative proteomics can be useful in identifying new epidemiological markers for N. meningitidis.  相似文献   
142.
143.
Active Ca2+ transport was measured in microsomal vesicles prepared from bovine retinae and was compared with that in disk membranes of the photoreceptor cells of the same retina. The 45Ca uptake was dependent on the presence of Mg(2+)-ATP and was inhibited by vanadate or when GTP substituted for ATP. The dependence of calcium uptake on the external free Ca2+ concentration gave a KM = 13 microM or a KM = 0.1 microM for disks and microsomal vesicles, respectively. A phosphorylated intermediate (E-P) of Ca(2+)-ATPase of about 100 kDa was isolated in microsomal vesicles. The E-P formation was strongly inhibited by thapsigargin and partially by 2,5-di-(-butyl)benzohydroquinone. Digestion of disks or microsomes with calpain had no effect on the phosphorylated intermediate, while digestion with trypsin produced two fragments of approximately 55 kDa and 35 kDa. These results suggest that bovine retinal microsomes contain a calcium pump belonging to the SERCA family.  相似文献   
144.
The production of lactic acid by Lactobacillus casei B-442 was studied and modeled. Sugar feedstock was provided using cashew apple juice, an alternative glucose and fructose feedstock that proved to yield high concentrations of lactic acid. The fermentations were carried out in a 1-L fermenter under constant agitation (150 rpm) and controlled pH (6.5). Lactic acid production was evaluated through a dynamic study, varying the initial concentration of sugar in the range of 20 to 60 g/L. Biomass, reducing sugars, and lactic acid concentration were measured throughout the experiments. The highest production of lactic acid (59.3 g/L) was obtained operating the fermentation with 60 g/L of reducing sugar from the cashew apple juice. A rigorous kinetic model was developed for batch fermentation of cashew apple juice for lactic acid production by L. casei B-442. The growth of biomass and lactic acid production were affected by substrate limitation, substrate inhibition and lactic acid inhibition. The model assumed growth- and non-growth-associated lactic acid production and a term for microorganism death was also included in the model. Parameters of the kinetic model were determined based on experimental data by using the least mean squares method and Levenberg–Marquardt algorithm. The model validation was performed and the model was statistically able to fit the profiles for growth of biomass, sugar consumption and lactic acid production. The optimization of the process, using the model, was carried out and the optimum operating conditions aiming highest productivity, lowest production cost and highest gross profit are presented.  相似文献   
145.
Cattle lameness is an important welfare concern that also has an economic impact on the dairy industry. It can be a significant problem among pasture-based herds. Our objectives were to identify cow- and herd-level factors related to lameness and hoof lesions in dairy cows grazing year-round in Minas Gerais, Brazil. We performed a cross-sectional study in 48 pasture-based dairy herds, visiting each farm in a single visit. We evaluated 2,262 cows for mobility score (0–3) and 392 cows for hoof lesions. We used a questionnaire and checklist to capture herd management data. All information obtained was used to build multivariable models. The factors associated with lameness were low body condition score, longer time spent in the corral, being kept in paddocks during the drought period, and poor hygiene. For hoof lesions, track features were the most significant factor in determining the likelihood of heel horn erosion, white line fissure, and sole hemorrhage—by more than 3 times. Different factors related to unhygienic conditions such as leg cleanliness, frequency of cleaning, and longer time spent in the corral were associated with infectious hoof lesions. Poor human–animal relationship was related to sole hemorrhage, but patient handling of cows on the track was a protective factor against interdigital hyperplasia. The results of this study suggest that improving hygiene conditions, track features, and cow handling can improve dairy cattle mobility scores in pasture-based farms under tropical conditions. These findings also represent a first step toward planning actions aimed at decreasing lameness and hoof lesions in the studied region.  相似文献   
146.
The purpose of this paper was to present the results of a life cycle cost analysis concerning the purchase and operation of a more efficient popular refrigerator model compared with a baseline design in Brazil. The summarized results may be useful for organizations working to promote sustainable energy development. This paper specifically focuses on refrigerators, since their energy consumption is predicted to constitute over 30% of the total average domestic electricity bill in Brazilian households. If all new Brazilian refrigerators had an energy efficiency at the level consistent with the least life cycle cost of ownership, it would result in an annual savings of 2.8 billion dollars (US$) in electricity bills, 45 TWh of electricity demand, and 18 Mt of CO2 emissions, with a respective payback period of 7 years which is less than half the average estimated lifetime of a refrigerator. The analysis was conducted following the guidelines of similar analyses available from the US Department of Energy and the Collaborative Labeling and Appliance Standards Program.
Edson Adriano VendrusculoEmail:
  相似文献   
147.
Fructooligosaccharides have been isolated from roots and leaves of Stevia rebaudiana, by hot aqueous extraction, followed by precipitation with ethanol. Their structure has been determined using methylation and NMR analysis, MALDI-TOF, and ESI-MS. Fructooligosaccharides contained almost exclusively (2→1)-linked β-fructofuranosyl, with terminal α-glucopyranosyl and β-fructofuranosyl units. MALDI-TOF and ESI-MS analyses showed the wide range of degree of polymerisation (DP) present in various extracts. From roots and leaves, three different fractions gave profiles of homologous series, with DPs ranging up to 17 with MALDI-TOF and 19 using ESI-MS. These inulin-type fructooligosaccharides were the major component of extracts from S. rebaudiana roots and significant components from the leaves.  相似文献   
148.
Wild-type P16/CDKN2 (p16INK4A, MTS1) cDNA, directed by the cytomegalovirus (CMV) immediate early promoter, was transfected into RT4 and RT112 bladder-carcinoma cell lines bearing a mutated endogenous P16/CDKN2 gene and lacking endogenous P16/CDKN2 respectively. In both cases, only transfected clones with rearranged exogenous P16/CDKN2 cDNA could be grown and propagated in cell culture. This result is reminiscent of transfection of wild-type p53 into cells with a deleted or mutated endogenous gene and suggests that P16/CDKN2, over-expressed under control of the strong CMV promoter, induces growth arrest in RT4 and RT112 cells. Transfer of human chromosome 9 to RT4 cells produced RT4/H9 hybrid clones retaining the P16/CDKN2 gene, since in RT4/H9 cell clones P16/CDKN2-gene expression is modulated by the physiological control of chromosomal regulatory sequence. All the RT4/H9 clones lost the entire chromosome 9, except clone 4 and clone 5, which maintained a deleted and an intact chromosome 9 respectively. Loss of several loci in 9p21, including P16/CDKN2, in tumors induced in nude mice by clone 4 and clone 5 suggests that P16/CDKN2 or other genes in 9p21 suppress tumorigenicity in bladder-carcinoma cells. Tumors induced by clone 4 and clone 5 show loss of markers in 9q. The regions 9q22.3, 9q32-33 and 9q34.2, which were maintained in the 2 clones and lost in their derived tumors, may contain tumor-suppressor genes relevant in bladder carcinoma. The results of this study suggest that the P16/CDKN2 gene controls growth of bladder-carcinoma cells when it is over-expressed, and may be involved in the development of bladder carcinoma, but other genes in 9p21 and 9q may participate in bladder-cancer progression.  相似文献   
149.
We report the first synthesis of polyimide aerogels cross-linked through a polyhedral oligomeric silsesquioxane, octa(aminophenyl)silsesquioxane (OAPS). Gels formed from polyamic acid solutions of 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA), bisaniline-p-xylidene (BAX) and OAPS were chemically imidized and dried using supercritical CO(2) extraction to give aerogels having density around 0.1 g/cm(3). The aerogels are greater than 90 % porous, have high surface areas (230 to 280 m(2)/g) and low thermal conductivity (14 mW/m-K at room temperature). Notably, the polyimide aerogels cross-linked with OAPS have higher modulus than polymer reinforced silica aerogels of similar density and can be fabricated as both monoliths and thin films. Thin films of the aerogel are flexible and foldable making them an ideal insulation for space suits, and inflatable structures for habitats or decelerators for planetary re-entry, as well as more down to earth applications.  相似文献   
150.
The authors report the case of a chronic myeloid leukemia (CML) patient submitted to allogenic bone marrow transplantation, who had probably never entered complete remission. The disease was reactivated as a granulocytic sarcoma, next to a platinum plate installed to correct a tibia fracture 11 years earlier. Its final event was a myeloid Ph1 + blastic crisis that was unsuccessfully treated with high doses of sc interferon and citarabine.  相似文献   
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