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41.
To enhance efforts related to controlling foodborne pathogens in the Middle East and North Africa (MENA), information on epidemiology of non‐typhoidal Salmonella enterica (hereafter termed “Salmonella”) is limited. We quantified the overall regional and country‐specific Salmonella prevalence in different human populations and identified the most common serotypes. Published literature of Salmonella prevalence was systematically reviewed and reported following the Preferred Items for Systematic Reviews and Meta‐Analysis (PRISMA) guidelines. Pooled Salmonella prevalence measures were estimated using a random‐effects model. We identified 46 research reports that reported 84 Salmonella prevalence measures in 15 out of 24 countries in MENA. There were 252,831 tested humans with 6,356 Salmonella‐positive cases. The pooled Salmonella prevalence in MENA was estimated at 6.6% (95% confidence interval (CI): 5.4%–7.9%). The highest pooled Salmonella prevalence measures were in Morocco (17.9%, 95% CI: 5.7%–34.8%, 1997–2012), Tunisia (10.2%, 95% CI: 4.3%–18.0%, 1988–2009) and Sudan (9.2%, 95% CI: 6.5%–12.2%, 2006–2008), while the lowest were in Jordan (1.1%, 95% CI: 0.1%–3.0%, 1993–2010), Oman (1.2%, 95% CI: 1.2%–1.3%, 1998–2002) and Palestine (1.2%, 95% CI: 0.4%–2.1%, 1999–2011). In MENA, Salmonella pooled prevalence in gastrointestinal symptomatic, gastrointestinal asymptomatic and food handlers population groups was 13.0% (95% CI: 7.6%–19.6%), 11.4% (95% CI: 2.2%–25.7%) and 3.8% (95% CI: 1.0%–8.0%), respectively. Salmonella prevalence was 14.5% (95% CI: 8.7%–26.1%) in studies tested <100 subjects, whereas 4.6% (95% CI: 3.6%–5.8%) in studies tested ≥100 subjects. Salmonella Enteritidis (29.8%) and Typhimurium (23.6%) were the most common serotypes. Salmonella was a common foodborne pathogen in MENA countries, particularly in North African countries. Findings inform the scientific community, the public and the decision‐makers with Salmonella prevalence and gaps in evidence in MENA to support control and prevention strategies and could leverage more research studies.  相似文献   
42.
Journal of Plant Diseases and Protection - Late blight, caused by Phytophthora infestans (Mont.) de Bary, is a devastating disease found worldwide. During 2011, 2013 and 2014 cropping seasons,...  相似文献   
43.
The aim of to study the effect of Ballota undulata (70% EtOH) extract on lipid profile on Rabbits. The plant extract was orally administered to the atherogenic rabbits (atherogenic diet + cholesterol powder supplement 400 mg/kg/body weight/day dissolved in 5 mL coconut oil) at dose of 1.2 g kg(-1) body weight/day. During the overall period of the experiment blood was collected and serum was analyzed for lipid profile. Animals were sacrificed; the heart and the liver were collected and kept at -20 degrees C until assayed. Biochemical analysis of blood serum and tissue (liver and heart muscle) level were made for cholesterol, phospholipids and triglycerides. In addition blood serum was analyzed further for HDL-Cholesterol. All the results were statistically analyzed using students t-test. Hypolipidaemic nature of Ballota undulata (70% EtOH) extract was studied in hyperlipidaemic Rabbits. The increased cholesterol levels were brought to normal by administration of Ballota undulata. Serum cholesterol levels dropped from 940.7 to 230.41 (75.55%) and further to 119.2 (87.32%) by the end of the experiment. Similarly, phospholipids and triglycerides levels were observed to be also reduced. The tissues lipids profiles of liver and heart muscle showed similar changes in those noticed in serum lipids. Ballota undulata possesses active hypolipidaemic constituents.  相似文献   
44.
Caper (Capparis L.), a shrub plant with a large natural distribution, is used in traditional medicines to cure various illnesses. Phytochemicals studies have shown the presence of many beneficial compounds such as spermidine, rutin, quercetin, kaempferol, stigmasterol, campesterol, tocopherols, and carotenoids. Biological studies reveal important antimicrobial, anti-oxidative, anti-inflammatory, immunomodulatory and antiviral properties. The presented review summarizes information concerning the morphology, ethnopharmacology, phytochemistry, and biological activities of caper plants.  相似文献   
45.
Summary

Cadmium (Cd) is a metal pollutant that accumulates in cultivated soils and has detrimental consequences in terms of food safety. Lettuce (Lactuca sativa) can be characterised as having a high capacity to accumulate Cd in its tissues. An analysis of Cd tolerance and Cd accumulation was carried out using two varieties of lettuce (‘Divina’ and ‘Melina’). A wide range of CdCl2 concentrations was used (0.0, 0.1, 0.6, 3.0, and 15.0 µM CdCl2). The lowest concentration (0.1 µM CdCl2) stimulated growth, while the two highest concentrations resulted in a reduction in biomass. Cadmium concentrations were found to be twice as high in roots as in shoots. ‘Divina’ displayed lower concentrations of Cd than ‘Melina’ in nearly all treatments. A strong negative correlation was observed between Cd concentration and Cd tolerance in the roots and shoots (R2 > 0.87) of both ‘Melina’ and ‘Divina’. Lettuce grown in the presence of 15.0 µM CdCl2 had leaf Cd concentrations that were 100-fold higher than the legal maximum level for vegetable products marketed for human consumption, but showed no symptoms of dehydration, chlorosis, or necrosis. This result represents an important alert for lettuce consumers and growers.  相似文献   
46.
This study assessed the impact of the use of magnesium chloride as a relaxant for the echinoid Paracentrotus lividus on the metabolic activity of individuals subjected to handling stress and aerial exposure. The variation in the gonad moisture content and biochemical composition was compared in sea urchins (P. lividus) treated with magnesium and untreated controls before transport and during 15 days of laboratory acclimation. Sea urchins treated with magnesium maintained higher levels of protein and carbohydrate throughout the trial in comparison with controls. However, the lipid level and fatty acid percentage remained stable during the experiment and no differences were found between treated or non‐treated sea urchins .  相似文献   
47.
The preservative effect of refrigerated and vacuum-packed sea bass (Dicentrarchus labrax) fillets inoculated with four mixtures of lactic acid bacteria (LAB) (Lactococcus lactis, Lactobacillus plantarum, and Carnobacterium piscicola) and incorporated with citrus essential oil (CEO) was evaluated on the basis of microbiological and biochemical analysis.

Initially, sea bass fillets showed high nutritional quality. During refrigerated storage, lipid contents did not show a significant decrease in any fish fillets; meanwhile, important proteolysis was observed in untreated control. In addition, results indicated that both CEO and LAB strains exhibited antimicrobial activity against spoilage, pathogenic, and fungi flora. Moreover, the total volatile bases (TVB-N) values were higher in control fillets, and the lowest TVB-N values were observed in Control CEO and C3 + CEO (30.47 ± 0.00 and 32.29 ± 1.12 mg TVB-N/100 g, respectively). Also, the levels of biogenic amines increased in all fillets without exceeding the upper limit of acceptability except for untreated control (sum of about 1396.63 ppm). Furthermore, this combined treatment ameliorated the muscle liquid-holding capacity, which improves technological properties.

Overall, this treatment may open new promising opportunities for the biopreservation of fish products by enhancing the period of storage of refrigerated and vacuum-packed sea bass fillets.  相似文献   

48.
Plants with limited transpiration rate (TR) under high vapor pressure deficit (VPD) offer the potential to conserve soil water and thus decrease the occurrence of soil water deficit. Genetic variability in TR response to VPD has been observed in the greenhouse for soybean (Glycine max (L.) Merr.) genotypes related to PI416937, but these differences have yet to be measured in the field. The objective of this study was to observe under field conditions leaf gas exchange properties of PI416937 in comparison to nine other genotypes to determine if it expressed limited TR at high VPD. Genotypic differences in stomatal conductance measurements (a proxy for TR) matched those obtained under controlled environment conditions. Genotypes varied from no stomatal response to VPD, to strong negative responses resulting in full stomata closure at ∼4 kPa. There was a greater proportional genetic variability in stomatal conductance in the field (75% at high VPD) than was observed in the greenhouse, but this variation was correlated with greenhouse TR. However, photosynthesis was considerably limited in genotypes that had a stomatal response to VPD. Although field differences in photosynthetic capacity among genotypes were not correlated with greenhouse measurements, there was sufficient genetic variation to allow the possibility of selection of high photosynthetic capacity to overcome about a 34% decrease in stomatal conductance. Thus, a targeted breeding program to combine the water conserving TR-VPD response with increased photosynthetic capacity has the potential to increase soybean yields in field water-deficit environments.  相似文献   
49.
  • ? Several reports on annual plants have already shown the involvement of epigenetic modifiers such as DNA methylation in their adaptation to abiotic stresses.
  • ? Nevertheless, the genotypic variations of epigenetic modifiers, their possible correlations with morphological traits and the impact of water deficit have not been described for perennial plants.
  • ? Six genotypes of Populus deltoides × P. nigra were subjected or not to a moderate water deficit treatment. Various morphological traits such as the height of the plants, their biomass and the total leaf area were measured to characterize the productivity in both conditions. Levels of DNA methylation, histone acetylation and the activities and isoform accumulation of the corresponding enzymes were measured at the shoot apex, the site of morphogenesis. Genotypic variation was observed for the morphological traits and the epigenetic variables and correlations were established among them. Genotypic variation for DNA methylation was detected in hybrid poplars. A positive correlation was demonstrated between DNA methylation percentage and productivity under well watered conditions.
  • ? While there was a general decrease of growth for all genotypes in response to a moderate water deficit, genotypic dependant variations of DNA methylation were found suggesting different strategies among hybrids.
  •   相似文献   
    50.
    In the present study, free amino acids and seed protein contents of pomegranate germplasm from Tunisia and China were conducted using Hitachi L8800 amino acid analyzer, Bradford and Kjeldahl methods. The work offers more consideration to protein pomegranate seeds which can be with great importance regarding the nutritive seed value of this crop. In other hand, the protein and amino acids contents were used to compare the Tunisian and Chinese pomegranate cultivars based on multivariate analyses (principal component and clustering analyses). Results show that the Tunisian and Chinese pomegranate seeds were rich in storage proteins independently of organoleptic taste as sweet, sour sweet or sour. Qualitatively, the storage protein and free amino acids of pomegranate seeds were identical. Besides, the segregation of Chinese and Tunisian pomegranate cultivars into three groups was reveled based on high, low or moderate amino acids contents. Statistically, the differences between organoleptic groups (sweet, sour sweet and sour) were not significant (P?<?0.05). However, the differences between pomegranate cultivars were statistically significant within groups. The separation of cultivars is independent to the organoleptic taste neither the geographical origin.  相似文献   
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