Author Keywords: Convective heat transfer coefficient; human body; forced convection; natural convection; heat flow meter 相似文献
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991.
Lipase was immobilized in liquid crystal-collagen membrane. No difference in the optimum pH between the lipase-liquid crystal-collagen membrane and native lipase was observed. However, the immobilized lipase shows flat-pH profiles. The activity of the lipase membrane on a platinum electrode used for cathode increased with increase in terminal voltage and then returned to the initial activity with decrease of terminal voltage. 相似文献
992.
Kentaro Ohigashi Aki Mizuguti Yasuyuki Yoshimura Kazuhito Matsuo Tetsuhisa Miwa 《Journal of plant research》2014,127(1):109-117
Hybridization between crops and their wild relatives potentially threatens the genetic identity of the wild plants, particularly in the case of genetically modified crops. Only a few studies have examined the use of temporal isolation to prevent hybridization, and the indices used in those studies, (e.g., the days of flowering overlap), are not precise to evaluate the degree of synchrony in flowering. Here we propose a flowering similarity index that can compare the degree of flowering synchrony between two relevant species and measure the efficiency of temporal isolation. The results showed that the flowering similarity index predicts the likelihood of hybridization much better than the number of flowering-overlap days, regardless of different flowering patterns among cultivars. Thus, temporal isolation of flowering or flowering asynchrony is the most effective means in preventing hybridization between crops and their wild relatives. 相似文献
993.
Masayuki Sugimoto Masato Wakabayashi Yoichi Shimizu Takeshi Yoshioka Kenichi Higashino Yoshito Numata Tomohiko Okuda Songji Zhao Shota Sakai Yasuyuki Igarashi Yuji Kuge 《PloS one》2016,11(3)
Obesity was reported to cause kidney injury by excessive accumulation of sphingolipids such as sphingomyelin and ceramide. Sphingomyelin synthase 2 (SMS2) is an important enzyme for hepatic sphingolipid homeostasis and its dysfunction is considered to result in fatty liver disease. The expression of SMS2 is also high in the kidneys. However, the contribution of SMS2 on renal sphingolipid metabolism remains unclear. Imaging mass spectrometry is a powerful tool to visualize the distribution and provide quantitative data on lipids in tissue sections. Thus, in this study, we analyzed the effects of SMS2 deficiency on the distribution and concentration of sphingomyelins in the liver and kidneys of mice fed with a normal-diet or a high-fat-diet using imaging mass spectrometry and liquid chromatography/electrospray ionization-tandem mass spectrometry. Our study revealed that high-fat-diet increased C18–C22 sphingomyelins, but decreased C24-sphingomyelins, in the liver and kidneys of wild-type mice. By contrast, SMS2 deficiency decreased C18–C24 sphingomyelins in the liver. Although a similar trend was observed in the whole-kidneys, the effects were minor. Interestingly, imaging mass spectrometry revealed that sphingomyelin localization was specific to each acyl-chain length in the kidneys. Further, SMS2 deficiency mainly decreased C22-sphingomyelin in the renal medulla and C24-sphingomyelins in the renal cortex. Thus, imaging mass spectrometry can provide visual assessment of the contribution of SMS2 on acyl-chain- and region-specific sphingomyelin metabolism in the kidneys. 相似文献
994.
Jun-ichi Furukawa Shota Sakai Ikuko Yokota Kazue Okada Hisatoshi Hanamatsu Takashi Kobayashi Yasunobu Yoshida Kenichi Higashino Tomohiro Tamura Yasuyuki Igarashi Yasuro Shinohara 《Journal of lipid research》2015,56(12):2399-2407
Glycosphingolipids (GSLs) are lipid molecules linked to carbohydrate units that form the plasma membrane lipid raft, which is clustered with sphingolipids, sterols, and specific proteins, and thereby contributes to membrane physical properties and specific recognition sites for various biological events. These bioactive GSL molecules consequently affect the pathophysiology and pathogenesis of various diseases. Thus, altered expression of GSLs in various diseases may be of importance for disease-related biomarker discovery. However, analysis of GSLs in blood is particularly challenging because GSLs are present at extremely low concentrations in serum/plasma. In this study, we established absolute GSL-glycan analysis of human serum based on endoglycoceramidase digestion and glycoblotting purification. We established two sample preparation protocols, one with and the other without GSL extraction using chloroform/methanol. Similar amounts of GSL-glycans were recovered with the two protocols. Both protocols permitted absolute quantitation of GSL-glycans using as little as 20 μl of serum. Using 10 healthy human serum samples, up to 42 signals corresponding to GSL-glycan compositions could be quantitatively detected, and the total serum GSL-glycan concentration was calculated to be 12.1–21.4 μM. We further applied this method to TLC-prefractionated serum samples. These findings will assist the discovery of disease-related biomarkers by serum GSL-glycomics. 相似文献
995.
Proliferation,morphology, and pluripotency of mouse induced pluripotent stem cells in three different types of alginate beads for mass production
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Ikki Horiguchi Mohammad M. Chowdhury Yasuyuki Sakai Yoji Tabata 《Biotechnology progress》2014,30(4):896-904
Induced pluripotent stem cells (iPSCs) are expected to be an ideal cell source for biomedical applications, but such applications usually require a large number of cells. Suspension culture of iPSC aggregates can offer high cell yields but sometimes results in excess aggregation or cell death by shear stress. Hydrogel‐based microencapsulation can solve such problems observed in Suspension culture, but there is no systematic evaluation of the possible capsule formulations. In addition, their biological effects on entrapped cells are still poorly studied so far. We, therefore, immobilized mouse iPSCs in three different types of calcium–alginate (Alg–Ca) hydrogel‐based microcapsules; (i) Alg–Ca capsules without further treatment (Naked), (ii) Alg–Ca capsules with poly‐l ‐lysine (PLL) coating (Coated), and (iii) Alg–PLL membrane capsules with liquid cores (Hollow). After 10 days of culture within the medium containing serum and leukemia inhibitory factor, we obtained good cellular expansions (10–13‐fold) in Coated and Hollow capsules that were similar to Suspension culture. However, 32 ± 9% of cellular leakage and lower cell yield (about threefold) were observed in Naked capsules. This was not observed in Coated and Hollow capsules. In addition, immunostaining and quantitative RT‐PCR showed that the formation of primitive endodermal layers was suppressed in Coated capsules contrary to all other formulations. This agenesis of primitive endoderm layers in Coated capsules is likely to be the main cause of the significantly better pluripotency maintenance in hydrogel‐based encapsulation culture. These results are helpful in further optimizing hydrogel‐based iPSC culture, which can maintain better local cellular environments and be compatible with mass culture. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:896–904, 2014 相似文献
996.
Hidekado Ishigaki Tetsumi Horikoshi Tomoki Uematsu Masato Sahashi Tadahiro Tsuchikawa Tohru Mochida Tetsuya Hieda Norio Isoda Hiroko Kubo 《Journal of thermal biology》1993,18(5-6):455-458
1. 1. The convective heat transfer coefficient of the human body is essential to predict convective heat loss from the body.
2. 2. The object of this paper is to calculate the convective heat transfer coefficient of the human body using heat flow meters and to estimate the thermally equivalent sphere and cylinder to the human body.
3. 3. The experimental formulae of the convective heat transfer coefficient for the whole body were obtained by regression analysis for natural, forced and mixed convection.
4. 4. Diameters of the thermally equivalent sphere and cylinder of the human body were calculated as 12.9 and 12.2 cm, respectively.
997.
T Nakamura K Takagaki M Majima S Kimura K Kubo M Endoss 《The Journal of biological chemistry》1990,265(10):5390-5397
Using chondroitin as a substrate, a new type of exo-beta-glucuronidase (EC 3.2.1.31) from rabbit liver was purified using a combination of ammonium sulfate fractionation, DEAE-cellulose chromatography, gel filtration on Sephracryl S-300, affinity chromatography through heparin-Sepharose CL-6B, and preparative polyacrylamide gel electrophoresis. This enzyme acts only on non-sulfated glycosaminoglycans and their oligosaccharides and was shown to be quite different from exo-beta-glucuronidase, which does act on p-nitro-phenyl-beta-D-glucuronide with regard to the following properties. 1) Neither sulfated glycosaminoglycanoligosaccharides nor p-nitrophenyl-beta-D-glucuronide were substrates for the enzyme. 2) The molecular weight was found to be about 130,000 by gel filtration, compared with a molecular weight of 280,000-300,000 for beta-glucuronidase, which acts on p-nitro-phenyl-beta-D-glucuronide. 3) The enzyme showed maximal activity at pH 5.0, compared with an optimum pH of 4.5 for beta-glucuronidase, which acts on p-nitro-phenyl-beta-D-glucuronide. 4) The enzyme showed maximal activity in 0.075 M NaCl but no activity above 0.25 M NaCl. 5) The enzyme was inhibited strongly by compounds bearing a sulfate group. 6) The enzyme did not react with an antibody against beta-glucuronidase acting on p-nitrophenyl-D-glucuronide. It is suggested that the enzyme may be involved in the catabolism of glycosaminoglycans, acting especially on chondroitin after the desulfation reaction and/or hyaluronic acid, but showing little involvement with the detoxification system. 相似文献
998.
Electrophoretic behavior of sodium dodecyl sulfate (SDS) in polyacrylamide gels has been examined at various gel concentrations. Micellar SDS is subject to significant molecular sieving from the gels while monomeric SDS is virtually free from the effect. The two forms are in a rapid equilibrium with each other. The gel concentration, therefore, has a signifieant effect on the electrophoresis of SDS added in SDS-polyacrylamide gel electrophoresis. The simplified procedure of Stoklosa and Latz (1974, Biochem. Biophys. Res. Commun.58, 74–79), in which SDS is added only in sample solutions, has been criticized based on the results obtained. 相似文献
999.
1000.