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991.
Proteins originating from dry legumes are not that much used in food formulations, yet, they are interesting components from a sustainability point of view, and could have interesting functional properties, e.g. for emulsion preparation. Therefore, this work focuses on the potential of the water soluble part of pea, chickpea and lentil protein isolates under acidic emulsions (pH 3.0) using a novel mild technique: premix membrane emulsification. Pea proteins (PP) and chickpea proteins (CP) lower the interfacial tension in the same way as whey protein isolate (WPI), which suggests that they could facilitate emulsion droplet formation similarly as WPI, while lentil proteins (LP) are slightly less effective. It is possible to make oil-in-water (O/W) emulsions with an average droplet diameter (d 4,3 ) of ~5 μm after 5 cycles in the premix system. The droplet size distribution of the emulsions remained constant during one day of storage, indicating that legume proteins are able to form and kinetically stabilize O/W emulsions. CP and PP exhibited emulsifying properties comparable to those of WPI, whereas LP is slightly less efficient, therewith indicating the great potential and that pea and chickpea protein isolates hold as emulsifiers in acidic food formulations.  相似文献   
992.
Plant trichomes play important protective functions and may have a major influence on leaf surface wettability. With the aim of gaining insight into trichome structure, composition, and function in relation to water-plant surface interactions, we analyzed the adaxial and abaxial leaf surface of holm oak (Quercus ilex) as a model. By measuring the leaf water potential 24 h after the deposition of water drops onto abaxial and adaxial surfaces, evidence for water penetration through the upper leaf side was gained in young and mature leaves. The structure and chemical composition of the abaxial (always present) and adaxial (occurring only in young leaves) trichomes were analyzed by various microscopic and analytical procedures. The adaxial surfaces were wettable and had a high degree of water drop adhesion in contrast to the highly unwettable and water-repellent abaxial holm oak leaf sides. The surface free energy and solubility parameter decreased with leaf age, with higher values determined for the adaxial sides. All holm oak leaf trichomes were covered with a cuticle. The abaxial trichomes were composed of 8% soluble waxes, 49% cutin, and 43% polysaccharides. For the adaxial side, it is concluded that trichomes and the scars after trichome shedding contribute to water uptake, while the abaxial leaf side is highly hydrophobic due to its high degree of pubescence and different trichome structure, composition, and density. Results are interpreted in terms of water-plant surface interactions, plant surface physical chemistry, and plant ecophysiology.Plant surfaces have an important protecting function against multiple biotic and abiotic stress factors (Riederer, 2006). They may, for example, limit the attack of insects (Eigenbrode and Jetter, 2002) or pathogenic fungi (Gniwotta et al., 2005; Łaźniewska et al., 2012), avoid damage caused by high intensities of UV and visible radiation (Reicosky and Hanover, 1978; Karabourniotis and Bormann, 1999), help to regulate leaf temperature (Ehleringer and Björkman, 1978; Ripley et al., 1999), and chiefly prevent plant organs from dehydration (Riederer and Schreiber, 2001).The epidermis of plants has been found to have a major degree of physical and chemical variability and may often contain specialized cells such as trichomes or stomata (Roth-Nebelsick et al., 2009; Javelle et al., 2011). Most aerial organs are covered with an extracellular and generally lipid-rich layer named the cuticle, which is typically composed of waxes embedded in (intracuticular waxes) or deposited on (epicuticular waxes) a biopolymer matrix of cutin, forming a network of cross-esterified hydroxy C16 and/or C18 fatty acids, and/or cutan, with variable amounts of polysaccharides and phenolics (Domínguez et al., 2011; Yeats and Rose, 2013). Different nano- and/or microscale levels of plant surface sculpturing have been observed by scanning electron microscopy (SEM), generally in relation to the topography of epicuticular waxes, cuticular folds, and epidermal cells (Koch and Barthlott, 2009). Such surface features together with their chemical composition (Khayet and Fernández, 2012) may lead to a high degree of roughness and hydrophobicity (Koch and Barthlott, 2009; Konrad et al., 2012). The interactions of plant surfaces with water have been addressed in some investigations (Brewer et al., 1991; Brewer and Smith, 1997; Pandey and Nagar, 2003; Hanba et al., 2004; Dietz et al., 2007; Holder, 2007a, 2007b; Fernández et al., 2011, 2014; Roth-Nebelsick et al., 2012; Wen et al., 2012; Urrego-Pereira et al., 2013) and are a topic of growing interest for plant ecophysiology (Helliker and Griffiths, 2007; Aryal and Neuner, 2010; Limm and Dawson, 2010; Kim and Lee, 2011; Berry and Smith, 2012; Berry et al., 2013; Rosado and Holder, 2013; Helliker, 2014). On the other hand, the mechanisms of foliar uptake of water and solutes by plant surfaces are still not fully understood (Fernández and Eichert, 2009; Burkhardt and Hunsche, 2013), but they may play an important ecophysiological role (Limm et al., 2009; Johnstone and Dawson, 2010; Adamec, 2013; Berry et al., 2014).The importance of trichomes and pubescent layers on water drop-plant surface interactions and on the subsequent potential water uptake into the organs has been analyzed in some investigations (Fahn, 1986; Brewer et al., 1991; Grammatikopoulos and Manetas, 1994; Brewer and Smith, 1997; Pierce et al., 2001; Kenzo et al., 2008; Fernández et al., 2011, 2014; Burrows et al., 2013). Trichomes are unicellular or multicellular and glandular or nonglandular appendages, which originate from epidermal cells only and develop outwards on the surface of plant organs (Werker, 2000). Nonglandular trichomes are categorized according to their morphology and exhibit a major variability in size, morphology, and function. On the other hand, glandular trichomes are classified by the secretory materials they excrete, accumulate, or absorb (Johnson, 1975; Werker, 2000; Wagner et al., 2004). Trichomes can be often found in xeromorphic leaves and in young organs (Fahn, 1986; Karabourniotis et al., 1995). The occurrence of protecting leaf trichomes has been also reported for Mediterranean species such as holm oak (Quercus ilex; Karabourniotis et al., 1995, 1998; Morales et al., 2002; Karioti et al., 2011; Camarero et al., 2012). There is limited information about the nature of the surface of trichomes, but they are also covered with a cuticle similarly to other epidermal cell types (Fernández et al., 2011, 2014).In this study and using holm oak as a model, we assessed, for the first time, the leaf surface-water relations of the abaxial (always pubescent) versus the adaxial (only pubescent in developing leaves and for a few months) surface, including their capacity to absorb surface-deposited water drops. Based on membrane science methodologies (Fernández et al., 2011; Khayet and Fernández, 2012) and following a new integrative approach, the chemical, physical, and anatomical properties of holm oak leaf surfaces and trichomes were analyzed, with the aim of addressing the following questions. Are young and mature adaxial and abaxial leaf surfaces capable of absorbing water deposited as drops on to the surfaces? Are young and mature abaxial and adaxial leaf surfaces similar in relation to their wettability, hydrophobicity, polarity, work of adhesion (Wa) for water, solubility parameter (δ), and surface free energy (γ)? What is the physical and chemical nature of the adaxial versus the abaxial trichomes, chiefly in relation to young leaves?  相似文献   
993.
Waardenburg anophthalmia syndrome, also known as microphthalmia with limb anomalies, ophthalmoacromelic syndrome, and anophthalmia-syndactyly, is a rare autosomal-recessive developmental disorder that has been mapped to 10p11.23. Here we show that this disease is heterogeneous by reporting on a consanguineous family, not linked to the 10p11.23 locus, whose two affected children have a homozygous mutation in SMOC1. Knockdown experiments of the zebrafish smoc1 revealed that smoc1 is important in eye development and that it is expressed in many organs, including brain and somites.  相似文献   
994.
Mitochondrial encephalopathy, lactic acidosis and strokelike episodes (MELAS) syndrome is a mitochondrial disorder characterized by a wide variety of clinical presentations and a multisystemic organ involvement. In this study, we report a Tunisian girl with clinical features of MELAS syndrome who was negative for the common m.3243A>G mutation, but also for the reported mitochondrial DNA (mtDNA) mutations and deletions. Screening of the entire mtDNA genome showed several known mitochondrial variants besides to a novel transition m.1640A>G affecting a wobble adenine in the anticodon stem region of the tRNA(Val). This nucleotide was conserved and it was absent in 150 controls suggesting its pathogenicity. In addition, no mutations were found in the nuclear polymerase gamma-1 gene (POLG1). These results suggest further investigation nuclear genes encoding proteins responsible for stability and structural components of the mtDNA or to the oxidative phosphorylation machinery to explain the phenotypic variability in the studied family.  相似文献   
995.
996.
997.
Increasing evidence indicates miRNAs as critical regulators of gene expression, but little information is available for miRNAs in intestinal diseases. Here, we investigated intestinal infections of male Balb/c mice with the coccidian parasite Eimeria papillata. On day 4 after oral infection, mice were shedding 3150 ± 430 oocysts per gram feces. This was associated with a low inflammatory response of the jejunum of mice evidenced by histology, non-response of IL-1β mRNA, even slight downregulation of IL-6 mRNA, only slight increases in iNOS mRNA, nitrate/nitrate, malondialdehyde, and a small decrease in glutathione, respectively. Only IFNγ mRNA was strongly induced. Using miRNA microarray technology, there were significantly upregulated the four miRNA species miR-1959, MCMV-miR-M23-1-5P, miR-203, and miR-21 out of 634 miRNAs, which was also confirmed by quantitative RT-PCR. Our data provide evidence that E. papillata parasites are able to induce specific miRNA species in their host target organ.  相似文献   
998.
Pyrococcus yayanosii CH1 is the first obligate piezophilic hyperthermophilic archaeon isolated from the deep-sea hydrothermal site Ashadze on the mid-Atlantic ridge at a depth of 4,100 m. This organism grows within a temperature range of 80 to 108°C and a hydrostatic pressure range of 20 to 120 MPa, with optima at 98°C and 52 MPa, respectively. Here, we report the complete genome sequence (1,716,817 bp, with a G+C content of 51.6%) of the type strain P. yayanosii CH1(T) (= JCM 16557). This genomic information reveals a systematic view of the piezoadaptation strategy and evolution scenario of metabolic pathways in Thermococcales.  相似文献   
999.
Thermococcus barophilus is a hyperthermophilic, anaerobic, mixed heterotrophic, and carboxydotrophic euryarchaeon isolated from the deep sea hydrothermal vent Snakepit site on the mid-Atlantic ridge at a depth of 3,550 m. T. barophilus is the first true piezophilic, hyperthermophilic archaeon isolated, having an optimal growth at 40 MPa. Here we report the complete genome sequence of strain MP, the type strain of T. barophilus. The genome data reveal a close proximity with Thermococcus sibiricus, another Thermococcus isolated from the deep biosphere and a possible connection to life in the depths.  相似文献   
1000.
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