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131.
A total of 41 strains of lactic acid bacteria (LAB) isolated from durum wheat sourdoughs used to produce Cornetto di Matera bread, were identified by SDS-PAGE of whole cell proteins (WCP) and screened for acid production ability, antimicrobial activity and exopolysaccharide (EPS) production. The isolates were identified as Lactobacillus plantarum (49%), Leuconostoc mesenteroides (17%), Lactobacillus curvatus (15%), Lactobacillus paraplantarum (12%), Weissella cibaria (5%) and Lactobacillus pentosus (2%). Several strains of Lb. plantarum and Leuc. mesenteroides showed a high acid production ability. The antagonistic activity was tested using an agar-spot deferred antagonism assay against a set of five indicators. The species had different profiles of inhibition. Lb. plantarum had the largest spectrum of inhibition, while no isolates of W. cibaria and Leuc. mesenteroides showed antimicrobial activity. No strains had antimicrobial activity against Bacillus cereus. The inhibitory activity of five strains was confirmed to be sensitive to proteolytic enzymes and thus potentially due to bacteriocin production. All Leuc. mesenteroides and W. cibaria strains produced EPS from sucrose. Some Lb. plantarum and Lb. paraplantarum strains produced EPS from different sugars in solid media. EPS production in liquid media was different within the species, with the highest production in liquid media containing glucose and maltose. A defined strain starter culture (W. cibaria DBPZ1006, Lb. plantarum DBPZ1015 and S. cerevisiae MTG10) was selected on the basis of technological properties and tested in model sourdough fermentations.  相似文献   
132.
While the Caribbean is a recognized “biodiversity hotspot”, plant conservation has not received adequate attention; particularly, given the high levels of endemism in many plant groups. Besides establishing protected areas, there needs to be a sustained effort to study the taxonomy, systematics and ecology of the flora. Recent phylogenetic studies have shown high levels of endemism and conservation studies indicate a large propotion of the flora is threatened with extinction. Eight recommendations are given for plant conservation in the region.  相似文献   
133.
Cholangiopathies are characterized by the heterogeneous proliferation of different-sized cholangiocytes. Large cholangiocytes proliferate by a cAMP-dependent mechanism. The function of small cholangiocytes may depend on the activation of inositol trisphosphate (IP(3))/Ca(2+)-dependent signaling pathways; however, data supporting this speculation are lacking. Four histamine receptors exist (HRH1, HRH2, HRH3, and HRH4). In several cells: 1) activation of HRH1 increases intracellular Ca(2+) concentration levels; and 2) increased [Ca(2+)](i) levels are coupled with calmodulin-dependent stimulation of calmodulin-dependent protein kinase (CaMK) and activation of cAMP-response element binding protein (CREB). HRH1 agonists modulate small cholangiocyte proliferation by activation of IP(3)/Ca(2+)-dependent CaMK/CREB. We evaluated HRH1 expression in cholangiocytes. Small and large cholangiocytes were stimulated with histamine trifluoromethyl toluidide (HTMT dimaleate; HRH1 agonist) for 24-48 h with/without terfenadine, BAPTA/AM, or W7 before measuring proliferation. Expression of CaMK I, II, and IV was evaluated in small and large cholangiocytes. We measured IP(3), Ca(2+) and cAMP levels, phosphorylation of CaMK I, and activation of CREB (in the absence/presence of W7) in small cholangiocytes treated with HTMT dimaleate. CaMK I knockdown was performed in small cholangiocytes stimulated with HTMT dimaleate before measurement of proliferation and CREB activity. Small and large cholangiocytes express HRH1, CaMK I, and CaMK II. Small (but not large) cholangiocytes proliferate in response to HTMT dimaleate and are blocked by terfenadine (HRH1 antagonist), BAPTA/AM, and W7. In small cholangiocytes, HTMT dimaleate increased IP(3)/Ca(2+) levels, CaMK I phosphorylation, and CREB activity. Gene knockdown of CaMK I ablated the effects of HTMT dimaleate on small cholangiocyte proliferation and CREB activation. The IP(3)/Ca(2+)/CaMK I/CREB pathway is important in the regulation of small cholangiocyte function.  相似文献   
134.
The capability of some ligninolytic fungi to degrade lignosulphonates has been studied. Three lignosulphonates concentrations, three culture media and seven different basidiomycetes in solid-cultures have been assayed to select the conditions for further experiments on submerged cultures. The best results of growth and lignosulphonate decolourization in solid-cultures were obtained with Pycnoporus sanguineus, Coriolus pubescens and Trametes sp. I-62 on Kirk's medium and 1% and 2% of lignosulphonate concentrations. In submerged cultures the lignosulphonate decolourization rate was generally higher when it was added on the 6th day, rather than when it was added from the beginning of the incubation and C. pubescens and P. sanguineus showed again the optimum results of decolourization. Extracellular laccase activity increased with lignosulphonate concentration in all assayed fungi, suggesting that lignosulphonate act as inductors of laccase activity.  相似文献   
135.
Degradation of aromatic hydrocarbons by aerobic bacteria is generally divided into an upper pathway, which produces dihydroxylated aromatic intermediates by the action of monooxygenases, and a lower pathway, which processes these intermediates down to molecules that enter the citric acid cycle. Bacterial multicomponent monooxygenases (BMMs) are a family of enzymes divided into six distinct groups. Most bacterial genomes code for only one BMM, but a few cases (3 out of 31) of genomes coding for more than a single monooxygenase have been found. One such case is the genome of Pseudomonas stutzeri OX1, in which two different monooxygenases have been found, phenol hydroxylase (PH) and toluene/o-xylene monooxygenase (ToMO). We have already demonstrated that ToMO is an oligomeric protein whose subunits transfer electrons from NADH to oxygen, which is eventually incorporated into the aromatic substrate. However, no molecular data are available on the structure and on the mechanism of action of PH. To understand the metabolic significance of the association of two similar enzymatic activities in the same microorganism, we expressed and characterized this novel phenol hydroxylase. Our data indicate that the PH P component of PH transfers electrons from NADH to a subcomplex endowed with hydroxylase activity. Moreover, a regulatory function can be suggested for subunit PH M. Data on the specificity and the kinetic constants of ToMO and PH strongly support the hypothesis that coupling between the two enzymatic systems optimizes the use of nonhydroxylated aromatic molecules by the draining effect of PH on the product(s) of oxidation catalyzed by ToMO, thus avoiding phenol accumulation.  相似文献   
136.
The objective was to determine the effect of body energy stores, evaluated by a body mass index (BMI), and food intake (FI), on the length of the anovulatory period and ovarian activity during the seasonal reproductive transitions in Creole goats. Non-pregnant, non-lactating Creole goats (n = 28) were fed to induce two different BMI conditions: Greater (GBMI; n = 15), and Lesser (LBMI; n = 13). Each BMI group was divided into two sub-groups, which were either feed restricted (FR) or non-feed restricted (NFR). Goats in the NFR groups received a diet containing 100% of the daily maintenance requirements (basal diet), while restricted goats were subjected to alternated periods, receiving 100% (11 d) and 60% (10 d) of the basal diet, during the entire experimental period. The experiment started after does were treated to synchronize time of estrus. Serum progesterone was determined in samples obtained twice a week, and used as a criterion for determining ovulations. During the transition to the anovulatory period three transrectal ovarian ultrasonographic scans were performed in a sub-group of 12 goats (n = 3 for each treatment combination). The diameter of the largest follicle (LFD) and the total number of antral follicles ≥2 mm (TAF) were recorded. Ultrasonographic ovarian scans were performed at 21, 42 and 63 days after the beginning of the experiment, concurrently with the end of each feed restriction period. The variables of response associated with ovulation were not influenced by BMI or BMI × FI interaction. However, FI influenced length of anovulatory season, as the anovulatory period was 30 d longer (P < 0.05) in the FR group as compared with the NFR group. Independently of treatments, TAF and LFD decreased from the first to the third ultrasonographic ovarian scan (13.2, 10.8 and 4.4 follicles; 3.7, 2.7 and 2.3 mm). Nevertheless, in PER 1 the number of TAF was greater (P < 0.05) in the FR as compared with NFR group and the GBMI group had a larger LFD (P < 0.05) as compared to the LBMI group. It is concluded, that temporal restriction in feed intake could affect the time of cessation and initiation of ovulations during the periods of transition to seasonal anestrus and return to estrous activity, and increase the length of the anovulatory period. In addition, ovarian follicular development during transition into the anovulatory period is differentially influenced by food intake and the status of body energy stores.  相似文献   
137.
Combined methodologies of immunohistochemistry, histochemistry and photometric image analysis were applied: (1) to characterise control equine skeletal muscle fibres according to their myosin heavy chain (MyHC) composition and (2) to determine on a fibre-to-fibre basis the correlation between contractile [i.e. MyHC(s), myofibrillar ATPase (mATPase) and sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA) isoforms], metabolic [i.e. succinate dehydrogenase (SDH) and alpha-glycerophosphate dehydrogenase (GPD) activities, glycogen and phospholamban (PLB) contents], and morphological [i.e. cross-sectional area (CSA), capillary and nuclear densities] features of individual myofibres. An accurate delineation of MyHC-based fibre types was obtained with the immunohistochemical method developed. This protocol showed a high sensitivity and objectivity to delineate hybrid fibres with overwhelming dominance of one MyHC isoform and, furthermore, it allowed a semiquantitative delineation of fast hybrid fibres according to the predominant MyHC isoform expressed. The phenotypic differences in contractile, metabolic and morphological properties seen between fibre types were related to MyHC content. Slow fibres had the lowest mATPase activity (related to shortening velocity), the highest SDH activity (oxidative capacity), the lowest GPD activity (glycolytic metabolism) and glycogen content, the smallest CSA, the greatest capillary and nuclear densities, and expressed slow SERCA isoform and PLB, but not the fast SERCA isoform. The reverse pattern was true for pure IID/X fibres, and type IIA fibres had intermediate properties. Hybrid IIAD/X fibres had mean values intermediate to those of their respective pure phenotypes. Discrimination of fibres according to their MyHC content was possible on the basis of their contractile and non-contractile profiles. These intrafibre interdependencies suggest that, even when controlled by different mechanisms, myofibres of control horses exhibit a high degree of co-ordination in their physiological, biochemical and anatomical features.  相似文献   
138.
139.
Bioprocess and Biosystems Engineering - This study assessed the simultaneous nitrification and denitrification processes and remaining organic matter removal from anaerobic reactor effluent...  相似文献   
140.
Immune-based treatments represent a promising new class of therapy designed to boost the immune system to specifically eradicate malignant cells. Immunotherapy may generate specific anti-tumor immune responses, and dendritic cells (DC), professional antigen-presenting cells, are widely used in experimental cancer immunotherapy. Several reports describe methods for the generation of mature, antigen-pulsed DC for clinical use. Improved quality and standardization are desirable to obtain GMP-compliant protocols. In this study we describe the generation of DC from 31 Glioblastoma (GB) patients starting from their monocytes isolated by immunomagnetic CD14 selection using the CliniMACS® device. Upon differentiation of CD14+ with IL-4 and GM-CSF, DC were induced to maturation with TNF-α, PGE2, IL-1β, and IL-6. Whole tumor lysate was obtained, for the first time, in a closed system using the semi-automated dissociator GentleMACS®. The yield of proteins improved by 130% compared to the manual dissociation method. Interestingly the Mean Fluorescence Intensity for CD83 increased significantly in DC pulsed with “new method” lysate compared to DC pulsed with “classical method” lysate. Our results indicate that immunomagnetic isolation of CD14+ monocytes using the CliniMACS® device and their pulsing with whole tumor lysate proteins is a suitable method for clinical-scale generation of high quality, functional DC under GMP-grade conditions.  相似文献   
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