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71.
Manchego cheese is a high-fat pressed ewe's-milk cheese made in Castilla-La Mancha (Spain) and produced by enzymatic coagulation. The minimum ripening time before marketing required by the Regulatory Board of the Manchego Cheese Appellation of Origin is 60 days.
This paper describes the physicochemical, proteolysis, sensory and texture characteristics of Manchego cheese, and the degree of homogeneity of cheeses made under the Manchego Appellation of Origin. The data gathered in this study indicate that sensory and instrumental analysis are useful tools for detecting changes in Manchego cheese during ripening. These changes were first detected by the instrumental analysis (2 months). The panelists detected differences after 4 months' ripening in all the factories. With physicochemical analysis, on the other hand, longer ripening times (6–8 months) are required before such changes become appreciated.  相似文献   
72.
73.
MEJÍAS, J. A. & VALDÉS, B., 1988. Karyologiepl studies in Sonchus section Madtimi (Asteraceae) from the Iberian Peninmula. Karyological data support the distinction of S. aquatilis Pourret and S. maritimus L. at the specific level. Karyological data and hybridization experiments support the idea that S. × novocaslcllanus Cirujano has been produced by the hybridization of S. crassifolius Pourret ex Willd. and S. maritimus L.  相似文献   
74.
The study of 500 blood donors, of 23 prostitutes, 22 confirmed AIDS cases and 19 ARC patients in Abidjan showed that HIV-2 prevalence in blood donors (3.4%) was somewhat higher than that of HIV-1 (2.4%). Furthermore HIV-2 alone was found associated with 14% of AIDS cases and 21% of ARC, while HIV-1 was associated with 32% of the cases. Antibodies to HIV-1 and HIV-2 were found in 54% of AIDS and ARC cases, as well as in 48% of the prostitutes sera. These preliminary results suggest that HIV-2 is pathogenic, being causally involved in some AIDS cases and does not protect from HIV-1 pathogenic potential.  相似文献   
75.

Background

The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) has launched several large-scale trials to determine the best strategies for gaining and sustaining control of schistosomiasis and transitioning toward elimination. In Côte d’Ivoire, a 5-year cluster-randomized trial is being implemented in 75 schools to sustain the control of schistosomiasis mansoni. We report Schistosoma mansoni infection levels in children one year after the initial school-based treatment (SBT) with praziquantel and compare with baseline results to determine the effect of the intervention.

Methodology

The baseline cross-sectional survey was conducted in late 2011/early 2012 and the first follow-up in May 2013. Three consecutive stool samples were collected from 9- to 12-year-old children in 75 schools at baseline and 50 schools at follow-up. Stool samples were subjected to duplicate Kato-Katz thick smears. Directly observed treatment (DOT) coverage of the SBT was assessed and the prevalence and intensity of S. mansoni infection compared between baseline and follow-up.

Principal Findings

The S. mansoni prevalence in the 75 schools surveyed at baseline was 22.1% (95% confidence interval (CI): 19.5–24.4%). The DOT coverage was 84.2%. In the 50 schools surveyed at baseline and one year after treatment, the overall prevalence of S. mansoni infection decreased significantly from 19.7% (95% CI: 18.5–20.8%) to 12.8% (95% CI: 11.9–13.8%), while the arithmetic mean S. mansoni eggs per gram of stool (EPG) among infected children slightly increased from 92.2 EPG (95% CI: 79.2–105.3 EPG) to 109.3 EPG (95% CI: 82.7–135.9 EPG). In two of the 50 schools, the prevalence increased significantly, despite a DOT coverage of >75%.

Conclusions/Significance

One year after the initial SBT, the S. mansoni prevalence had decreased. Despite this positive trend, an increase was observed in some schools. Moreover, the infection intensity among S. mansoni-infected children was slightly higher at the 1-year follow-up compared to the baseline situation. Our results emphasize the heterogeneity of transmission dynamics and provide a benchmark for the future yearly follow-up surveys of this multi-year SCORE intervention study.  相似文献   
76.
77.
Fagara zanthoxyloides Lam. (syn. Zanthoxylum zanthoxyloides) (Rutaceae) is the most cited Fagara species for the treatment and the prevention of sickle cell disease crisis. Sickle cell anemia (SCA) is a public health problem in many countries particularly in Africa. The present study was designed to evaluate the antisickling properties of three isomeric divanilloylquinic acids (3,4-O-divanilloylquinic acid or burkinabin A; 3,5-O-divanilloylquinic acid or burkinabin B and 4,5-O-divanilloylquinic acid or burkinabin C) identified previously by LC/MS/NMR analysis in the root bark of F. zanthoxyloides [Ouattara et al., 2004. LC/MS/NMR analysis of isomeric divanilloylquinic acids from the root bark of Fagara zanthoxyloides Lam. Phytochemistry 65, 1145–1151].The three isomers showed interesting antisickling properties which increased from burkinabins A to C.  相似文献   
78.
Spatio‐temporal dynamics of phytoplankton and their relation to abiotic environmental factors in four rivers of south‐eastern Ivory Coast (Soumié, Eholié, Ehania and Noé) was analysed from July 2003 to March 2005. The pelagic zone of each river was sampled upstream and downstream. Phytoplankton abundance was higher in Noé River (154.3 104 cells l?1) and lower in Eholié river (23.05 104 cells l?1). Dominant taxa were Microcystis aeruginosa (Kütz.) Lemmerm. and Aphanocapsa incerta (Lemmerm.) Cronberg & Komárek. In general, minimum densities of phytoplankton were observed during the rainy season, while maximum were observed in dry season in the whole stations of the rivers studied, such periods corresponding to low and high concentrations of nitrates. Among the rivers surveyed, Eholié river seems to be the least disturbed because of its higher species diversity. Seasonality fluctuations of algae abundance appear to be influenced by the flow of water and nitrate levels. This work is a useful starting point for future research on micro algae in Ivory Coast.  相似文献   
79.
The potential of the HER2-targeting antibody trastuzumab as a radioimmunoconjugate useful for both imaging and therapy was investigated. Conjugation of trastuzumab with the acyclic bifunctional chelator CHX-A″-DTPA yielded a chelate:protein ratio of 3.4 ± 0.3; the immunoreactivity of the antibody unaffected. Radiolabeling was efficient, routinely yielding a product with high specific activity. Tumor targeting was evaluated in mice bearing subcutaneous (s.c.) xenografts of colorectal, pancreatic, ovarian and prostate carcinomas. High uptake of the radioimmunoconjugate, injected intravenously (i.v.), was observed in each of the models and the highest tumor %ID/g (51.18 ± 13.58) was obtained with the ovarian (SKOV-3) tumor xenograft. Specificity was demonstrated by the absence of uptake of 111In-trastuzumab by melanoma (A375) s.c. xenografts and 111In-HuIgG by s.c. LS-174T xenografts. Minimal uptake of i.v. injected 111In-trastuzumab in normal organs was confirmed in non-tumor-bearing mice. The in vivo behavior of 111In-trastuzumab in mice bearing intraperitoneal (i.p.) LS-174T tumors resulted in a tumor %ID/g of 130.85 ± 273.34 at 24 h. Visualization of tumor, s.c. and i.p. xenografts was achieved by γ-scintigraphy and PET imaging. Blood pool was evident as expected but cleared over time. The blood pharmacokinetics of i.v. and i.p. injected 111In-trastuzumab was determined in mice with and without tumors. The data from these in vitro and in vivo studies supported advancement of radiolabeled trastuzumab into two clinical studies, a Phase 0 imaging study in the Molecular Imaging Program of the National Cancer Institute and a Phase 1 radioimmunotherapy study at the University of Alabama.Key words: monoclonal antibody, HER2, trastuzumab, radioimmunodiagnosis, radioimmunotherapy  相似文献   
80.
Pectinolytic enzymes play an important role in cocoa fermentation. In this study, we characterized three extracellular pectate lyases (Pels) produced by bacilli isolated from fermenting cocoa beans. These enzymes, named Pel-22, Pel-66, and Pel-90, were synthesized by Bacillus pumilus BS22, Bacillus subtilis BS66, and Bacillus fusiformis BS90, respectively. The three Pels were produced under their natural conditions and purified from the supernatants using a one-step chromatography method. The purified enzymes exhibited optimum activity at 60°C, and the half-time of thermoinactivation at this temperature was approximately 30 min. Pel-22 had a low specific activity compared with the other two enzymes. However, it displayed high affinity for the substrate, about 2.5-fold higher than those of Pel-66 and Pel-90. The optimum pHs were 7.5 for Pel-22 and 8.0 for Pel-66 and Pel-90. The three enzymes trans-eliminated polygalacturonate in a random manner to generate two long oligogalacturonides, as well as trimers and dimers. A synergistic effect was observed between Pel-22 and Pel-66 and between Pel-22 and Pel-90, but not between Pel-90 and Pel-66. The Pels were also strongly active on highly methylated pectins (up to 60% for Pel-66 and Pel-90 and up to 75% for Pel-22). Fe2+ was found to be a better cofactor than Ca2+ for Pel-22 activity, while Ca2+ was the best cofactor for Pel-66 and Pel-90. The amino acid sequences deduced from the cloned genes showed the characteristics of Pels belonging to Family 1. The pel-66 and pel-90 genes appear to be very similar, but they are different from the pel-22 gene. The characterized enzymes form two groups, Pel-66/Pel-90 and Pel-22; members of the different groups might cooperate to depolymerize pectin during the fermentation of cocoa beans.Cocoa fermentation is a key step in the technological transformation of cocoa into chocolate (6, 33, 35). The fermentation of cocoa beans occurs at two levels: the first level involves reactions that take place in the pulp, in the outer part of the beans, and the second-level reactions are located deep within the cotyledons.Reactions occurring in the pulp mainly concern the transformation of carbohydrates into ethanol and organic acids by a microflora essentially composed of yeast, lactic acid bacteria, acetic acid bacteria, and Bacillus (35). The resulting organic acids produced by the microbial metabolism diffuse into the bean and provoke lowering of the inner pH (16). The low pH, combined with the rise in temperature of the fermenting mass, activates two acidic-pH-dependent enzymes present in the cotyledons: an aspartic endoprotease and a serine carboxypeptidase (6, 7, 43). The combined actions of these enzymes leads to the transformation of storage proteins into hydrophobic amino acids (5), which are known to be the main precursor molecules of cocoa and the eventual chocolate aroma (4, 35).The fermentation process is also associated with the actions of various other plant cell wall-degrading enzymes, namely, pectinolytic enzymes. These enzymes, which allow the degradation of the cocoa pulp (34, 35, 36), facilitate the diffusion of microbial metabolites (essentially acetic acid) into the beans. Furthermore, the oligomers generated from the degradation of pectin polymers are used as a carbon source for the growth of the microorganisms. In view of the role they play, pectinolytic enzymes are not only essential for the normal course of cocoa fermentation, they are also key to the good quality of fermented and dried beans (3, 35).Pectinolytic enzymes are classified into two mains groups according to their mode of attack on pectin molecules: de-esterifying enzymes (pectin methyl esterase [EC 3.1.1.11]), which remove the methoxyl group from pectin, and depolymerases, which cleave the β(1,4)glycosidic bonds between galacturonate units, either by hydrolysis (polygalacturonase [EC 3.2.1.15]) or by trans-elimination (pectin lyase [EC 4.2.2.10] and pectate lyase [Pel] [EC 4.2.2.2]). Among these enzymes, the class of pectate lyases is widely distributed in bacteria and fungi, some phytopathogenic (1, 14, 15) and others, such as members of the genus Bacillus (2, 24, 39, 40), nonpathogenic. Pectate lyases are classified into different families according to their primary amino acid sequences (11, 38). The classification can be found on the CAZy (Carbohydrate-Active EnZymes database) server (http://www.cazy.org/) (10).Over the last 3 decades, polygalacturonase secreted by yeasts has been the sole pectinolytic enzyme identified in cocoa fermentation. However, we recently reported the involvement of pectate lyases produced by Bacillus strains in the cocoa fermentation process (26).Here, we report the biochemical and molecular properties of purified pectate lyases from three different Bacillus strains isolated from fermenting cocoa beans and the characterization of their cloned genes.  相似文献   
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