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1.
Lactoferrin (LF) is an 80-kDa globular glycoprotein with high affinity for metal ions, particularly for iron. This protein possesses many biological functions, including the binding and release of iron and serves as one of the important components of the innate immune system, where it acts as a potent inhibitor of several pathogens. LF has efficacious antibacterial and antiviral activities against a wide range of Gram-positive and Gram-negative bacteria and against both naked and enveloped DNA and RNA viruses. In its antiviral pursuit, LF acts predominantly at the acute phase of the viral infection or even at the intracellular stage, as in hepatitis C virus infection. LF inhibits the entry of viral particles into host cells, either by direct attachment to the viral particles or by blocking their cellular receptors. This wide range of activities may be attributed to the capacity of LF to bind iron and its ability to interfere with the cellular receptors of both hosts and pathogenic microbes.  相似文献   
2.
Lattice Boltzmann models (LBM) are rapidly showing their ability to simulate a lot of fluid dynamics problems that previously required very complex approaches. This study presents a LBM for simulating diffusion–advection transport of substrate in a 2-D laminar flow. The model considers the substrate influx into a set of active cells placed inside the flow field. A new innovative method was used to simulate the cells activity using the LBM by means of Michaelis–Menten kinetics. The model is validated with some numerical benchmark problems and proved highly accurate results. After validation the model was used to simulate the transport of oxygen substrates that diffuse in water to feed a set of active cartilage cells inside a new designed bioreactor.  相似文献   
3.
Mangoes (Mangifera indica) are grown in many warm regions of the world; for example, in Australia, Brazil, India, South America, and the United States (California and Florida), and along the shores of the Mediterranean sea (Egypt, Italy, and Spain). In Egypt, many varieties yielding delicious fruits are grown in large quantities (50,000 tons annually). Mango kernels are used for feeding mammals and chickens. Starch has been isolated from mango and its physical properties studied.The aim of the present work was to study the polysaccharides present in mango kernels.  相似文献   
4.
Summary The influence of total nitrification to nitrate or partial nitrification to nitrite on the soil organic nitrogen status was examined. NH 4 +15N was added to the soil in the absence and the presence of NaClO3, respectively nitrapyrin. The first chemical inhibits only nitrate formation, the second inhibits total nitrification. The accumulation of nitrite nitrogen in the soil at levels up to 5 mg kg–1 increased the loss of nitrogen. Yet, it did not increase the binding of mineral nitrogen into soil organic matter, relative to the control soil. The data suggest that the biochemistry of the nitrite formation process, rather than the levels of nitrite ions formed, are of primary importance in the role of nitrification mediated nitrosation of soil organic matter.  相似文献   
5.
Trafficking protein particle complex 9 (TRAPPC9) is a major subunit of the TRAPPII complex. TRAPPC9 has been reported to bind nuclear factor κB kinase subunit β (IKKβ) and NF-kB-inducing kinase (NIK) where it plays a role in the canonical and noncanonical of nuclear factor-κB (NF-kB) signaling pathways, receptively. The role of TRAPPC9 in protein trafficking and cytoskeleton organization in osteoclast (OC) has not been studied yet. In this study, we examined the mRNA expression of TRAPPC9 during OC differentiation. Next, we examined the colocalization of TRAPPC9 with cathepsin-K, known to mediate OC resorption suggesting that TRAPPC9 mediates the trafficking pathway within OC. To identify TRAPPC9 protein partners important for OC-mediated cytoskeleton re-organization, we conducted immunoprecipitation of TRAPPC9 in mature OCs followed by mass spectrometry analysis. Our data showed that TRAPPC9 binds various protein partners. One protein with high recovery rate is L-plastin (LPL). LPL localizes at the podosomes and reported to play a crucial role in actin aggregation thereby actin ring formation and OC function. Although the role of LPL in OC-mediated bone resorption has not fully reported in detail. Here, first, we confirmed the binding of LPL to TRAPPC9 and, then, we investigated the potential regulatory role of TRAPPC9 in LPL-mediated OC cytoskeleton reorganization. We assessed the localization of TRAPPC9 and LPL in OC and found that TRAPPC9 is colocalized with LPL at the periphery of OC. Next, we determined the effect of TRAPPC9 overexpression on LPL recruitment to the actin ring using a viral system. Interestingly, our data showed that TRAPPC9 overexpression promotes the recruitment of LPL to the actin ring when compared with control cultures. In addition, we observed that TRAPPC9 overexpression reorganizes actin clusters/aggregates and regulates vinculin recruitment into the OC periphery to initiate podosome formation.  相似文献   
6.
Work aimed at assessing status and introducing water conservation regimes for coffee production in southern Saudi Arabian highlands. Data on farm locations, altitudes, areas, practices, irrigation, tree density, and annual coffee production were analyzed. Field experiment using chlorophyll fluorescence and different irrigation regimes was conducted to examine effects of reducing irrigation frequency on photosynthesis. Results indicated that Coffea arabica L. is commonly grown at altitudes of 1300–1400 m. Plants grown at 4–6 Trees m?2 using 100 kg ha?1 mineral fertilizer produce an average of 3 t ha?1. High frequency 2-day-intervals irrigation regime practiced by farmers during the dry season presents ecological challenge to limited local artesian water resources. Changes in chlorophyll fluorescence under 14-day-intervals irrigation regime initiated water stress that markedly inhibited Photosystem II efficiency and quantum yield and increased non-photochemical energy dissipation. Applying a 7-day-intervals irrigation regime induced less inhibitory effects on Photosystem II. Results also indicated that shifting from 2-day-intervals irrigation regime to 7-day-intervals regime improves coffee agroecology and directs coffee production towards sustainability.  相似文献   
7.
The recovery of ovarian function during breast-feeding   总被引:3,自引:0,他引:3  
The pattern of breast-feeding was daily recorded and the serum concentrations of prolactin (PRL), FSH, LH, estradiol (E2) and progesterone (prog) were measured at weekly intervals in 26 breast-feeding mothers from the time of delivery and up to the resumption of regular ovulation or to the end of the first postpartum year. Twelve postpartum non-breast-feeding women were similarly studied as controls. An algorithm was used to characterize ovulatory events into three types: the first, with evidence highly suggestive of normal ovulation (EHSO), the second, with evidence of probable ovulation (EPO) and the third with evidence indicating questionable ovulation or deficient corpus luteum function (QO/DCT). Pregnancy preceded the first menstruation in one woman in each of the breast-feeding and control groups. Of the 19 breast-feeding women who started to menstruate during the first postpartum year, five had EHSO, one had EPO, 5 had EQO/DCL and 7 had anovulatory (AO) menstruation. The corresponding figures in the 11 controls were 6, 2, 3 and 0. Pregnancy occurred before a second menstruation in one woman in both the study group and the controls. In 18 breast-feeding women observed, the second menstruation was preceded by EHSO in 7, by EPO in 3, by EQO/DCL in one and AO in 7. In 10 controls the corresponding figures were 7, 3, 0 and 0. Out of a total of 79 menstruations observed during breast-feeding the incidence of AO was 30% and of QO/DCL was 15%. In actively breast-feeding mothers, hyperprolactinemia persisted for more than 1 yr. However, menstruation and ovulation occasionally occurred before the drop of PRL to concentrations seen during the normal menstrual cycle. In the majority of women, low E2 levels were present during lactational amenorrhea, but with occasional spikes in some. A few women maintained somewhat high values of E2 for several weeks before the resumption of menstruation. The implications of these hormonal findings to the attempts to improve on the contraceptive effect of breast-feeding are discussed.  相似文献   
8.
Development of the phytoseiid mitePhytoseiulus persimilis Athias-Henriot was studied when fed on three mite species as prey. The tenuipalpid mite,Brevipalpus pulcher (Canestrini & Fanzago), is an unsuitable prey forP. persimilis as predatory larvae reared on any stages developed to the protonymphal stage only. WhenP. persimilis larvae were reared on the eriophyid mite,Eriophyes dioscoridis Soliman & Abou-Awad, only a few developed to adulthood, but failed to oviposit. On the contrary, predatory larvae fed on the tetranychid mite,Tetranychus urticae Koch, matured in a significantly shorter period and resulting females exhibited a high rate of reproduction.  相似文献   
9.
Summary The formation of mineral nitrogen species and of organic nitrogen was studied in three different types of soils in relation to the application of the nitrification inhibitor nitrapyrin. The results indicate that nitrification brings about a deficit in total mineral nitrogen and a concomitant surplus in non biomass organic nitrogen. This phenomenon increases with increasing levels of applied ammonium nitrogen and soil organic matter. The phenomenon is considered to be due to the reaction of the transient nitrite formed with soil phenolic compounds and appears to be of significance in all soils in which nitrification occurs, even neutral to alkaline and low carbon soils.  相似文献   
10.
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