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21.
Kiwellin, an allergenic protein formerly isolated from green kiwi fruit, has been identified as the most abundant component of the gold kiwi species. A protein named KiTH, showing a 20 kDa band on reducing SDS-PAGE and 100% identity with the C-terminal region of kiwellin, has been identified in the extract of the ripe green species. In vitro treatment of purified kiwellin with the protease actinidin from green kiwi fruit originated KiTH and kissper, a recently described pore-forming peptide. Primary structure analysis and experimental evidence suggest that kiwellin is a modular protein with two domains. It may undergo in vivo proteolytic processing by actinidin, thus producing KiTH and kissper. When probed with sera recognizing kiwellin from green kiwi fruit, KiTH showed IgE binding, with reactivity levels sometimes different from those of kiwellin. The IgE-binding capacity of kiwellin from gold kiwi fruit appears to be similar to that of the green species.  相似文献   
22.
OBJECTIVES: To look at trends in generalised (body mass index (BMI) >or=30 kg m(-2)) and abdominal (waist circumference (WC) >102 cm in men, >88 cm in women) obesity among adults between 1993 and 2003, and to evaluate their association with diabetes, hypertension and hypertension-diabetes co-morbidity (HDC) in England. DESIGN: Analyses of nationally representative cross-sectional population surveys, the Health Survey for England (HSE). SUBJECTS: Non-institutionalised men and women aged >or=35 years. MEASUREMENTS: Interviewer-administered questionnaire (sociodemographic information, risk factors, doctor-diagnosed diabetes), measurements of height and weight to calculate BMI. WC and blood pressure measurements were taken by trained nurses. RESULTS: Generalised obesity increased among men from 15.8% in 1993 to 26.3% in 2003, and among women from 19.3% to 25.8%. Abdominal obesity also increased in both sexes (men: 26.2% in 1993 to 39.0% in 2003; women: 32.4% to 47.0%). In 1994, 1998 and 2003, generalised and abdominal obesity were independently associated with risk of hypertension, diabetes and HDC. The odds of diabetes associated with generalised obesity in 1994, 1998 and 2003 were 1.62, 2.26 and 2.62, respectively, in women and 1.24, 1.82 and 2.10, respectively, in men. Similar differences were observed for hypertension and HDC. Men and women with abdominal obesity also showed a higher risk for diabetes, hypertension and HDC than those with a normal WC. CONCLUSIONS: If current trends in obesity continue then the risk of related morbidities may also increase. This will impact on cardiovascular disease morbidity and mortality, with cost implications for the health service. Therefore there is an urgent need to control the epidemic of obesity.  相似文献   
23.
Sixteen novel and ten known galactolipids have been isolated and characterized from the leaves of Ipomoea batatas L. (sweet potato) using an analytical method based on high-performance liquid chromatography coupled with electrospray ionization-quadrupole time-of-flight tandem mass spectrometry. Using this technique, the structures and regiochemistries of the fatty acyl groups and the positions of the double bonds on the acyl chains were determined. Sugar moieties were identified by analysis of one- and two-dimensional nuclear magnetic resonance spectra. The positions of the double bonds of polyunsaturated fatty acids were confirmed, and in some cases their geometries determined, by gas chromatography-mass spectrometry. This is the first report of galactolipids in the leaves of sweet potato.  相似文献   
24.
Journal of Soils and Sediments - Erosion is one of the main soil degradation problems. It diminishes soil biological activity and therefore its quality. The aim of the study was to evaluate if the...  相似文献   
25.
The Gram-negative -Proteobacterium Wolbachia pipientis has been described as an obligate endosymbiont in many arthropod species, where it induces a variety of reproductive alterations, including parthenogenesis. Recently, this microorganism has also been detected in the parthenogenetic collembolan Folsomia candida. Here, we confirm the occurrence of the endosymbiont also in two Italian parthenogenetic populations of F. candida using ultrastructural (electron microscopy) and molecular (PCR screening on two bacterial genes) evidence. The strain isolated in the Italian populations has almost-identical gene sequences compared to that previously isolated in other populations of F. candida. In addition, we discovered a population of Folsomia cf. candida, which showed the presence of both males and females. This population is not infected by Wolbachia. A screening of two mitochondrial genes (COI and COII) showed that the bisexual population has high levels of genetic divergence in comparison with the parthenogenetic ones, even suggesting the possibility that it belongs to a different species. Furthermore, the remarkably high levels of genetic divergence between the two parthenogenetic populations suggests a possible influence of Wolbachia on inducing such differentiation, and, in the long term, speciation.  相似文献   
26.
The objective of this work was to quantify the flavonoids present in foods most commonly consumed by the Brazilian population. The predominant flavonoids found in largest abundance in all of the analyzed vegetables were glycosides of quercetin. In lettuce, a small amount of luteolin was also detected. In sweet pepper, quercetin and luteolin were both present. White onion [48-56 mg/100 g of fresh weight (FW), expressed as aglycon], red onion (40-100 mg/100 g of FW), red lettuce (67-67.2 mg/100 g of FW), arugula (41-118 mg/100 g of FW), and chicory (18-38 mg/100 g of FW) were highest in total flavonoids. In fruits, the highest concentrations of flavonoids were found in the peel (125-170 mg/100 g of FW) and pulp (35-44 mg/100 g of FW) of oranges and in some apple varieties (14-36 mg/100 g of FW). Variability in flavonoid content due to time of harvesting was high for leafy vegetables and red onions. The estimated ingestion by Brazilian population ranged from 60 to 106 mg/day.  相似文献   
27.
Although an antioxidant mechanism has been involved in the beneficial effects of ferulic acid in human diseases, there are few reports on the antioxidant properties of this compound in isolated membranes and intact cells. Here, we evaluated the ability of ferulic acid in inhibiting lipid peroxidation in rat liver microsomal membranes and reactive oxygen species production in NIH-3T3 fibroblasts, induced by both tert-BOOH and AAPH. We also compared its antioxidant efficiency with that of other antioxidants, such as alpha-tocopherol, beta-carotene, and ascorbic acid, added alone or in combination. Ferulic acid acted as a potent antioxidant in our models, being more effective in protecting from tert-BOOH than from AAPH. Moreover, the compound was the most effective among the antioxidants tested. Synergistic interactions were observed when the compound was used in combination with the other antioxidants, suggesting that they can cooperate in preserving physiological integrity of cells exposed to free radicals.  相似文献   
28.
29.
A study was conducted to determine the contaminantlevel of the Sarno River basin, a small creek located insouthwestern Italy. Six sampling site locations were selected tocoincide with two previous studies conducted in 1975 and 1985 toprovide a basis for comparison. For each location, twelve sampleswere collected over the period October 1997–September 1998.Results indicated a degradation in river water quality, especiallynear the mouth. This was reflected by a dissolved oxygenconcentration of about 0.8 mg L-1 near the urban areas ofScafati, Pompei and Castellamare of Stabia. At the same locations,BOD5 and COD values were two to five times higher than theallowable regulatory maximum levels, respectively. About 4 kmfrom the headwaters, the average oxygen concentration was 4.7 mgL-1, BOD5 values were close to the standard limit (37 vs 40 mg L-1), and COD values were above the standard limits(252 vs 160 mg L-1). Highest concentrations were detectedduring peak tomato production. During this time, settleable solidswere also elevated, two to six times the regulatory standard.Coliform bacteria densities were found in excess of the standardlimits at all sites. Near the head of the river, mean fecalcoliform (22,571 MPN mL-1) and streptococci densities (14,214 MPN mL-1) surpassed the regulatory level of 120 and 20 MPN mL-1, respectively, reflecting the input from the urbansettings of Sarno and agricultural fields. The heavy metaldissolved concentrations were low at all sampling sites. Most ofthe analyzed contaminants increased when comparend with 1985data. BOD5 increased 5 to 10 times at sites near the urbansettings of Scafati, Pompei and Castellamare di Stabia, whereasCOD increases were twofold at all sites. A decline of chromiumlevels was observed due to the recent effective treatment ofwaste water from the tanning plants.  相似文献   
30.
A number of N2-alkyl and N2-acyl derivatives of guanosine 5'-phosphate (GMP) have been synthesized and tested for their synergistic effect with monosodium L-glutamate (MSG), the prototypical substance imparting umami taste to savory-based foods. Capacities to enhance the taste intensity of MSG (gamma values) were estimated through subjective comparisons of MSG/nucleotide mixtures in water with appropriate solutions of MSG alone. Assuming beta = gamma[nucleotide]/gamma[IMP], beta values of the N2-substituted GMPs were found in the range 1.2-5.7. Such values appear to be related to the chain length of the substituent in the 2-position of the purine nucleus and dependent on the replacement of a CH 2 group with an S atom and/or with an alpha-CO group. These findings indicate that the exocyclic NHR group of the guanine moiety is actively implicated in the synergism between GMP derivatives and MSG. Theoretical calculations suggest that an anti conformation is probably assumed by ribonucleotide molecules interacting with umami receptors.  相似文献   
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