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81.
Epidemiological data show that the consumption of added sugars as ingredients in processed or prepared foods and caloric beverages has dramatically increased. Fructose and fructose-based sweeteners are the most commonly added sugars and high-fructose corn syrup (HFCS-55: 55% fructose, 42% glucose and 3% higher saccharides) accounts for over 40% of all added caloric sweeteners. Concerns regarding the health risk of added sugar follow the demonstration that the consumption of foods and beverages high in sugars is associated with an increased prevalence of obesity, insulin resistance, dyslipidemia and, more recently, ischemic heart and kidney diseases. The molecular mechanism(s) underlying the detrimental effects of sugar are not completely understood and their elucidation is critical to provide new insights on the health risk of fructose-based sweeteners. A better understanding of the key role of fructose overconsumption in the development of metabolic disorders may contribute to planning new strategies for preventing deleterious dietary behaviors from becoming established and, thus, curbing the rise in the number of insulin-resistant, obese and diabetic populations worldwide.  相似文献   
82.
The purpose of this study was to evaluate the film formation ability and mechanical stress–strain properties of aqueous native corn starches, using free films and film coatings applied to tablets. Free films were prepared from high-amylose corn (Hylon VII), corn and waxy corn starches, using sorbitol and glycerol as plasticizers. The tablets and pellets were film-coated using an air-suspension coater, and characterized with respect to the film coating surface topography, cross-sectional structure and thickness (SEM), and dissolution in vitro. The amylose content of the starch film formers affected both the tensile strength and the elongation. The elongations were under 5% for even the plasticized starches, and in most cases, no plasticization effect was seen by either of the plasticizers. Dissolution of native corn starch film-coated tablets (weight gain 1%) did not differ from uncoated ones. A notable delay in dissolution of the drug was found by increasing Hylon VII film coating thickness, suggesting controlled-release characteristics.  相似文献   
83.
Spastic paraplegia type 10 (SPG10) is an autosomal dominant form of hereditary spastic paraplegia (HSP) due to mutations in KIF5A, a gene encoding the neuronal kinesin heavy chain implicated in anterograde axonal transport. KIF5A mutations were found in both pure and complicated forms of the disease; a single KIF5A mutation was also detected in a CMT2 patient belonging to an SPG10 mutant family. To confirm the involvement of the KIF5A gene in both CMT2 and SPG10 phenotypes and to define the frequency of KIF5A mutations in an Italian HSP patient population, we performed a genetic screening of this gene in a series of 139 HSP and 36 CMT2 affected subjects. We identified five missense changes, four in five HSP patients and one in a CMT2 subject. All mutations, including the one segregating in the CMT2 patient, are localized in the kinesin motor domain except for one, falling within the stalk domain and predicted to generate protein structure destabilization. The results obtained indicate a KIF5A mutation frequency of 8.8% in the Italian HSP population and identify a region of the kinesin protein, the stalk domain, as a novel target for mutation. In addition, the mutation found in the CMT2 patient strengthens the hypothesis that CMT2 and SPG10 are the extreme phenotypes resulting from mutations in the same gene.  相似文献   
84.
Zhang W  Xue T  Wu X  Zhang P  Zhao G  Peng D  Hu S  Wang X  Liu X  Liu W  Liu X 《Vaccine》2011,29(45):8032-8041

Background

The H5N1 subtype of highly pathogenic avian influenza viruses has spread to over 63 countries in Asia, Europe, and Africa and has become endemic in poultry. Since 2004, vaccination against H5N1 influenza has become common in domestic poultry operations in China. Most influenza vaccines have been produced in embryonated chicken eggs. High yield is the essential feature of a good vaccine candidate virus.

Objective

Therefore, the large-scale manufacture of such a vaccine requires that the viral yield of H5N1 reassortant vaccine viruses in eggs and MDCK cells be increased.

Methods

We generated two sets of reassortant H5N1 viruses based on backbone viruses A/Chicken/F/98 (H9N2) and A/Puerto Rico/8/34 (H1N1) using reverse genetics. The HAs and NAs of the reassortants were derived from the three epidemic H5N1 strains found in China. We compared the replication properties of these recombinant H5N1 viruses in embryonated chicken eggs and MDCK cells after inserting either 20 or 38 amino acids into their NA stalks.

Results

In this study, we demonstrated that inserting 38 amino acids into the NA stalks can significantly increase the viral yield of H5N1 reassortant viruses in both embryonated chicken eggs and MDCK cells, while inserting only 20 amino acids into the same NA stalks does not. Hemagglutinin inhibition testing and protection assays indicated that recombinant H5N1 viruses with 38 aa inserted into their NA stalks had the same antigenicity as the viruses with wt-NA.

Conclusion

These results suggest that the generation of an H5N1 recombinant vaccine seed by the insertion of 38 aa into the NA stalk may be a suitable and more economical strategy for the increase in viral yield in both eggs and MDCK cells for the purposes of vaccine production.  相似文献   
85.
垂体柄中断综合征(PSIS)是以不同程度的垂体前叶激素分泌缺乏为主要临床表现的罕见疾病,其影像学特征为垂体柄缺如或纤细,常合并垂体后叶高信号异位、垂体前叶发育不良.目前病因仍不明确.鞍区动态增强MRI有助于明确诊断.各种垂体前叶激素替代是有效治疗手段.医生应加强认识、积极治疗,以改善患者预后.  相似文献   
86.
87.
Body stalk anomaly is a rare malformation. This anomaly in monozygotic twins is extremely unusual. We describe a case of monoamniotic pregnancy discordant for body stalk anomaly diagnosed at 11 weeks. Ultrasound showed a fetus with a large anterior abdominal wall defect, anomaly of the spine and no evidence of lower extremities and other with a normal morphology. As far as our concern, only three monoamniotic pregnancies discordant for this malformation were reported. Our case represents the fourth reported monoamniotic pregnancy discordant for body stalk anomaly with diagnosis made by ultrasound and the second diagnosed in the first trimester.  相似文献   
88.
Objective: This study evaluated the physicochemical properties, fatty acid (FA) and phytochemical compositions, and free radical–scavenging potentials of oils from the bagasses: Costus afer stem (CA) and Saccharum officinarum stem (SB); agricultural residues; corn cobs (CC); tigernut chaff (TB); peanut hulls (GH); medicinal plants: Sphenocentrum jollyanum leaves (SJ) and Senna alata leaves (CS); and fodders: Pennisetum purpureum (PP), Panicum maximum (PM), and Chloris gayana stalks (CG).

Method: Oils from the samples were extracted using a mixture of n-hexane and isopropyl alcohol (3:2). The oils were analyzed for physicochemical properties using standard procedures, phytochemicals and FAs contents using gas chromatography-fluorescent ionization detection, and free radical–scavenging potentials using spectrophotometric methods of determination.

Results: The bagasse and residue oils contained lower moisture contents (1.13%–2.38%) and acid values (1.89–9.20?mg/KOH/g), while the GH oil produced the least refractive indices, saponification value, and oil yield. CA oil contained 78% saturated FA, while SB oils contained 73.65% saturated FA and an abundance of lignoceric, palmitoleic, oleic, and arachidic acid. CC oil contained mostly behenic acid (19.65%), and GH oil produced 87.04% saturated FA, while TB oil produced 56% unsaturated FA. Oils from SJ, CS, PP, PM, and CG contained between 48.34% and 57.09% unsaturated FA. The phytochemical composition showed that ribalinidine and sapogenin were most abundant in PM oil, while lunamarine, kaempferol, and catechin were most abundant in SJ oil. GH oil produced the highest amounts of phytate (53.81?µg/ml) and oxalate (39.47?µg/ml). TB oil and oils from SJ and CS, especially at higher concentrations, matched the scavenging potentials of the standards used.

Conclusions: Due to the thermal stability and amount of short chain fatty acids (SFAs) of the SB, CA, CC, and GH oils, they are more suitable for non-food industrial purposes, while TB, SJ, and CS oil properties are recommendable for therapeutic purposes, especially for relief of oxidative stress.  相似文献   

89.
90.
The first part of this study evaluates the occurrence of mycotoxin patterns in feedstuffs and fish feeds. Results were extrapolated from a large data pool derived from wheat (n = 857), corn (n = 725), soybean meal (n = 139) and fish feed (n = 44) samples in European countries and based on sample analyses by liquid chromatography/tandem mass spectrometry (LC-MS/MS) in the period between 2012–2019. Deoxynivalenol (DON) was readily present in corn (in 47% of the samples) > wheat (41%) > soybean meal (11%), and in aquafeeds (48%). Co-occurrence of mycotoxins was frequently observed in feedstuffs and aquafeed samples. For example, in corn, multi-mycotoxin occurrence was investigated by Spearman’s correlations and odd ratios, and both showed co-occurrence of DON with its acetylated forms (3-AcDON, 15-AcDON) as well as with zearalenone (ZEN). The second part of this study summarizes the existing knowledge on the effects of DON on farmed fish species and evaluates the risk of DON exposure in fish, based on data from in vivo studies. A meta-analytical approach aimed to estimate to which extent DON affects feed intake and growth performance in fish. Corn was identified as the ingredient with the highest risk of contamination with DON and its acetylated forms, which often cannot be detected by commonly used rapid detection methods in feed mills. Periodical state-of-the-art mycotoxin analyses are essential to detect the full spectrum of mycotoxins in fish feeds aimed to prevent detrimental effects on farmed fish and subsequent economic losses for fish farmers. Because levels below the stated regulatory limits can reduce feed intake and growth performance, our results show that the risk of DON contamination is underestimated in the aquaculture industry.  相似文献   
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