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The first step of urine formation is the selective filtration of the plasma into the urinary space at the kidney structure called the glomerulus. The filtration barrier of the glomerulus allows blood cells and large proteins such as albumin to be retained while eliminating the waste products of the body. The filtration barrier consists of three layers: fenestrated endothelial cells, glomerular basement membrane, and podocytes. Podocytes are specialized epithelial cells featured by numerous, actin-based projections called foot processes. Proteins on the foot process membrane are connected to the well-organized intracellular actin network. The Rho family of small GTPases (Rho GTPases) act as intracellular molecular switches. They tightly regulate actin dynamics and subsequent diverse cellular functions such as adhesion, migration, and spreading. Previous studies using podocyte-specific transgenic or knockout animal models have established that Rho GTPases are crucial for the podocyte health and barrier function. However, little attention has been paid regarding subcellular locations where distinct Rho GTPases contribute to specific functions. In the current review, we discuss cellular events involving the prototypical Rho GTPases (RhoA, Rac1, and Cdc42) in podocytes, with particular focus on the subcellular compartments where the signaling events occur. We also provide our synthesized views of the current understanding and propose future research directions.  相似文献   
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Synthesised E- and Z-ajoene were used to determine their amounts in food oils containing various fresh garlics. The best yield of E-ajoene (172.0 μg/g of garlic) and Z-ajoene (476.0 μg/g of garlic) was obtained from freshly prepared Japanese garlic with rice oil which was heated at 80 °C. Determination of E- and Z-ajoene from soybean oil containing 15% Japanese garlic samples prepared at 80 °C for 0.5 h gave the amount of E-ajoene (170.0 μg/g of garlic) and Z-ajoene (127.0 μg/g of garlic). After 9-month storage, 54.0% E- and 11.0% Z-ajoene remained in Japanese garlic with rice oil. Ajoene (0.1 mM) in ethyl acetate was incubated under UV-light (253.7 nm) for 3 days, 81.7% E- and 56.9% Z-ajoene remained. 4.3% and 0.5% E- and Z-ajoene remained when ajoene (0.1 mM in ethyl acetate) was incubated at 100 °C.  相似文献   
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Biomass refers to renewable energy sources and comes from biological materials such as trees, plants, manure as well as municipal solid wastes. Effective utilization of biomass as an energy resource requires the use of an optimization model to take into account biomass availability, transportation distances, and the scales and locations of power facilities within a region. In this study, we develop a new analytical tool that integrates cost, energy savings, greenhouse gas considerations, scenario analysis, and a Geographic Information System (GIS) to provide a comprehensive analysis of alternative systems for optimizing biomass energy production. The goal is to find a system that optimizes the use of biomass waste by analyzing the cost, net avoided CO2 emission, and net energy savings with the objective of profit maximization. In this paper, we describe an application of the modeling tool described above to one of the fastest growing agriculture industries in Asia, the palm oil industry, for the case of Malaysia. Five scenarios utilizing palm oil waste as energy resources are discussed. The scenario of installing of new Combined Heat and Power (CHP) plants in the region yielded a number of benefits in terms of net energy savings, net avoided CO2 emission, and profits. The results also demonstrate the benefits of utilizing excess heat for biomass pre-treatment. The choice of a suitable CHP plant scale, management strategies for biomass seasonal availability, and market price of biomass are also important factors for effective use of the biomass in a region.  相似文献   
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The orphan nuclear receptor steroidogenic factor 1 (NR5A1 (SF-1)) is expressed in both Sertoli and Leydig cells in the testes. This study investigates the postnatal development of the testes of a gonad-specific Nr5a1 knockout (KO) mouse, in which Nr5a1 was specifically inactivated. The KO testes appeared histologically normal from postnatal day 0 (P0) until P7. However, disorganized germ cells, vacuoles, and giant cells appeared by P14 in the seminiferous tubules of KO but not control mice. Expression of NR5A1 and various factors was examined by immunohistochemistry (IHC). The number of NR5A1-positive Sertoli cells in the KO testes was lower compared with controls at all the developmental stages and decreased to nearly undetectable levels by P21. IHC for anti-Müllerian hormone and p27, immature and mature Sertoli cell markers, respectively, indicated a delay in Sertoli cell maturation in the KO testes. The number of Sertoli cell-expressing factors involved in Sertoli cell differentiation including WT1, SOX9, GATA4, and androgen receptor were lower in the KO testes compared with controls. Furthermore, fewer proliferating cell nuclear antigen-positive proliferative germ cells were observed, and the number of TUNEL-labeled cells was significantly higher in the KO testes compared with controls at P14 and P21, indicating impaired spermatogenesis. IHC for CYP11A1 (SCC) indicated the presence of steroidogenic Leydig cells in the interstitium of the KO testes at all stages examined. These results suggest that NR5A1 is essential for Sertoli cell maturation and therefore spermatogenesis, during postnatal testis development.  相似文献   
46.
The applicability of GC, GC/MS and liquid chromatography with tandem mass spectrometry (LC/MS/MS) to screening for 140 pesticides in agricultural products was examined. Validation of multi-residue screening methods for the determination of 88 pesticides in 12 crops (asparagus, cauliflower, burdock, carrot, broccoli, spinach, matsutake mushroom, orange, soybean, sesame, millet and tea) was done by GC and GC/MS. Of the 88 pesticides, 63 were obtained with recoveries in the range from 50 to 150% at the 0.1 microg/g level in the 12 crops. Applicability of the official methods in Japan to 74 pesticides, including 22 pesticides with low recovery (< 50%) by GC or GC/MS analysis, was also examined by LC/MS/MS. LC/MS/MS acquisition parameters were established for 67 pesticides in positive and negative electrospray ionization (ESI) modes. Of 67 pesticides validated in 7 crops using LC/MS/MS at the 0.1 microg/g level, 44 showed recoveries in the range from 50 to 150%. The occurrence of matrix interference in LC/MS/MS can lead to false-positive detection of MCPA in spinach, cabbage and orange and false-negative detection of four pesticides in orange, spinach, apple and unpolished rice. Good linearity was observed in the studied ranges by GC, GC/MS (r > 0.990) and LC/MS/MS (r > 0.995). Of the total of 140 pesticides validated by GC, GC/MS and LC/MS/MS, 107 were newly recognized as suitable subjects for screening.  相似文献   
47.
目前在土木工程,建筑,汽车等领域里使用的复合材料中,玻璃纤维是用量最大的增强材料。由于保护地球环境的呼声日趋高涨,天然纤维被期待着代替源于石油而且再利用困难的玻璃纤维,成为绿色复合材料的必要材料之一。本文通过注射成型工艺制作了玻璃短纤维,大麻短纤维以及混杂型纤维增强复合材料,并在拉伸实验中应用两种不同频率的声发射技术检测了拉伸断裂特性。实验发现,随着大麻纤维的加入和混杂复合材料绿色度的增加,复合材料的拉伸弹性模量随之线性增大,而拉伸强度基本保持不变。当大麻纤维的含量超过20wt%的时候,拉伸强度开始降低。在不同频率的声发射实验中,混杂型复合材料的声发射事件的产生都比单一纤维增强型复合材料要来的晚,也就是说,纤维的混杂有助于推迟微裂纹的产生。  相似文献   
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Diabetic patients are prone to severe bacterial infections. The functional alterations of neutrophils by hyperglycemia are thought to be partially responsible for such infections. In this study, we investigated the functional changes of neutrophil-like differentiated cell lines (dHL-60, dTHP-1, and dNB-4) by treatment with 5.5 mM, 11 mM, or 35 mM of glucose. In dHL-60 cells, the incubation with high glucose (35 mM) resulted in the enhancement of cell aggregation, the suppression of cellular fragility, the induction of reactive-oxygen species (ROS) production by phorbol myristate acetate (PMA) stimulation, and the impairment of phagocytosis. In dTHP-1 cells, the treatment with higher glucose generated the suppression of cellular fragility and extremely impaired phagocytosis (by 35 mM), and induced ROS production due to PMA stimulation (by 11 mM). Furthermore, the higher glucose exposure to dNB-4 cells enlarged intracellular vacuoles (by 35 mM) and induced ROS production due to PMA stimulation (by 11 mM). Since the ROS generation of those cells was enhanced only after PMA stimulation under the higher glucose conditions, glucose may have a priming effect rather than a triggering effect. These extraordinary sensitivities caused by the higher glucose treatments may reflect the dysfunction or overactivation of neutrophils.  相似文献   
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