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71.
Transcellular transport of fluorescein dextran through an arterial endothelial cell monolayer 总被引:2,自引:0,他引:2
R Hashida C Anamizu Y Yagyu-Mizuno S Ohkuma T Takano 《Cell structure and function》1986,11(4):343-349
Transcellular transport of fluorescein dextran (FD) of various molecular weights (4K, 10K, 20K, 70K and 150K daltons) through porcine arterial endothelial cells cultured on a type I collagen gel supported by a dacron sheet was studied and compared with the transport of low density lipoprotein labeled with rhodamine B (RB-LDL) described previously (Hashida et al., Cell Struct. Funct. 11, 31-42, 1986). The rate of FD transport through the monolayer depended on the size of the FD. FD transport was not temperature-dependent and was not a saturable process. Our findings show that FD transport differs from RB-LDL transport which is temperature- and dose-dependent. The mechanism of the transport of FD is compared with that of RB-LDL. 相似文献
72.
Farooqahmed S. Kittur Mamudou Bah Stephanie Archer-Hartmann Chiu-Yueh Hung Parastoo Azadi Mayumi Ishihara David C. Sane Jiahua Xie 《PloS one》2013,8(10)
Asialo-erythropoietin, a desialylated form of human erythropoietin (EPO) lacking hematopoietic activity, is receiving increased attention because of its broader protective effects in preclinical models of tissue injury. However, attempts to translate its protective effects into clinical practice is hampered by unavailability of suitable expression system and its costly and limit production from expensive mammalian cell-made EPO (rhuEPOM) by enzymatic desialylation. In the current study, we took advantage of a plant-based expression system lacking sialylating capacity but possessing an ability to synthesize complex N-glycans to produce cytoprotective recombinant human asialo-rhuEPO. Transgenic tobacco plants expressing asialo-rhuEPO were generated by stably co-expressing human EPO and β1,4-galactosyltransferase (GalT) genes under the control of double CaMV 35S and glyceraldehyde-3-phosphate gene (GapC) promoters, respectively. Plant-produced asialo-rhuEPO (asialo-rhuEPOP) was purified by immunoaffinity chromatography. Detailed N-glycan analysis using NSI-FTMS and MS/MS revealed that asialo-rhuEPOP bears paucimannosidic, high mannose-type and complex N-glycans. In vitro cytoprotection assays showed that the asialo-rhuEPOP (20 U/ml) provides 2-fold better cytoprotection (44%) to neuronal-like mouse neuroblastoma cells from staurosporine-induced cell death than rhuEPOM (21%). The cytoprotective effect of the asialo-rhuEPOP was found to be mediated by receptor-initiated phosphorylation of Janus kinase 2 (JAK2) and suppression of caspase 3 activation. Altogether, these findings demonstrate that plants are a suitable host for producing cytoprotective rhuEPO derivative. In addition, the general advantages of plant-based expression system can be exploited to address the cost and scalability issues related to its production. 相似文献
73.
Akari Nishigaki Mihoko Maruyama Munenori Numata Chisako Kanzaki Shun‐Ichi Tanaka Hiroshi Y. Yoshikawa Masayuki Imanishi Masashi Yoshimura Yusuke Mori Kazufumi Takano 《Engineering in Life Science》2020,20(9-10):395-401
It is known that interfaces have various impacts on crystallization from a solution. Here, we describe crystallization of acetaminophen using a microflow channel, in which two liquids meet and form a liquid–liquid interface due to laminar flow, resulting in uniform mixing of solvents on the molecular scale. In the anti‐solvent method, the microflow mixing promoted the crystallization more than bulk mixing. Furthermore, increased flow rate encouraged crystal formation, and a metastable form appeared under a certain flow condition. This means that interface management by the microchannel could be a beneficial tool for crystallization and polymorph control. 相似文献
74.
Yoshikazu Hashida Katsuaki Takechi Tomomi Abiru Noriyuki Yabe Hiroaki Nagase Koro Hattori Susumu Takio Yoshikatsu Sato Mitsuyasu Hasebe Hirokazu Tsukaya Hiroyoshi Takano 《The Plant journal : for cell and molecular biology》2020,101(6):1318-1330
In Arabidopsis thaliana the ANGUSTIFOLIA (AN) gene regulates the width of leaves by controlling the diffuse growth of leaf cells in the medio‐lateral direction. In the genome of the moss Physcomitrella patens, we found two normal ANs (PpAN1‐1 and 1‐2). Both PpAN1 genes complemented the A. thaliana an‐1 mutant phenotypes. An analysis of spatiotemporal promoter activity of each PpAN1 gene, using transgenic lines that contained each PpAN1‐promoter– uidA (GUS) gene, showed that both promoters are mainly active in the stems of haploid gametophores and in the middle to basal region of the young sporophyte that develops into the seta and foot. Analyses of the knockout lines for PpAN1‐1 and PpAN1‐2 genes suggested that these genes have partially redundant functions and regulate gametophore height by controlling diffuse cell growth in gametophore stems. In addition, the seta and foot were shorter and thicker in diploid sporophytes, suggesting that cell elongation was reduced in the longitudinal direction, whereas no defects were detected in tip‐growing protonemata. These results indicate that both PpAN1 genes in P. patens function in diffuse growth of the haploid and diploid generations but not in tip growth. To visualize microtubule distribution in gametophore cells of P. patens, transformed lines expressing P. patens α‐tubulin fused to sGFP were generated. Contrary to expectations, the orientation of microtubules in the tips of gametophores in the PpAN1‐1/1‐2 double‐knockout lines was unchanged. The relationships among diffuse cell growth, cortical microtubules and AN proteins are discussed. 相似文献
75.
Chuya Shinzato Konstantin Khalturin Jun Inoue Yuna Zayasu Miyuki Kanda Mayumi Kawamitsu Yuki Yoshioka Hiroshi Yamashita Go Suzuki Noriyuki Satoh 《Molecular biology and evolution》2021,38(1):16
The genus Acropora comprises the most diverse and abundant scleractinian corals (Anthozoa, Cnidaria) in coral reefs, the most diverse marine ecosystems on Earth. However, the genetic basis for the success and wide distribution of Acropora are unknown. Here, we sequenced complete genomes of 15 Acropora species and 3 other acroporid taxa belonging to the genera Montipora and Astreopora to examine genomic novelties that explain their evolutionary success. We successfully obtained reasonable draft genomes of all 18 species. Molecular dating indicates that the Acropora ancestor survived warm periods without sea ice from the mid or late Cretaceous to the Early Eocene and that diversification of Acropora may have been enhanced by subsequent cooling periods. In general, the scleractinian gene repertoire is highly conserved; however, coral- or cnidarian-specific possible stress response genes are tandemly duplicated in Acropora. Enzymes that cleave dimethlysulfonioproprionate into dimethyl sulfide, which promotes cloud formation and combats greenhouse gasses, are the most duplicated genes in the Acropora ancestor. These may have been acquired by horizontal gene transfer from algal symbionts belonging to the family Symbiodiniaceae, or from coccolithophores, suggesting that although functions of this enzyme in Acropora are unclear, Acropora may have survived warmer marine environments in the past by enhancing cloud formation. In addition, possible antimicrobial peptides and symbiosis-related genes are under positive selection in Acropora, perhaps enabling adaptation to diverse environments. Our results suggest unique Acropora adaptations to ancient, warm marine environments and provide insights into its capacity to adjust to rising seawater temperatures. 相似文献
76.
Khairul Salleh Basaruddin Naoki Takano Takayoshi Nakano 《Computer methods in biomechanics and biomedical engineering》2013,16(2):162-174
An assessment of the mechanical properties of trabecular bone is important in determining the fracture risk of human bones. Many uncertainty factors contribute to the dispersion of the estimated mechanical properties of trabecular bone. This study was undertaken in order to propose a computational scheme that will be able to predict the effective apparent elastic moduli of trabecular bone considering the uncertainties that are primarily caused by image-based modelling and trabecular stiffness orientation. The effect of image-based modelling which focused on the connectivity was also investigated. A stochastic multi-scale method using a first-order perturbation-based and asymptotic homogenisation theory was applied to formulate the stochastically apparent elastic properties of trabecular bone. The effective apparent elastic modulus was predicted with the introduction of a coefficient factor to represent the variation of bone characteristics due to inter-individual differences. The mean value of the predicted effective apparent Young's modulus in principal axis was found at approximately 460 MPa for respective 15.24% of bone volume fraction, and this is in good agreement with other experimental results. The proposed method may provide a reference for the reliable evaluation of the prediction of the apparent elastic properties of trabecular bone. 相似文献
77.
Hiroyuki Hayakawa Hiromichi Tanaka Kazuhiro Haraguchi Masami Mayumi Masako Nakajima Takashi Sakamaki 《Nucleosides, nucleotides & nucleic acids》2013,32(1):121-128
Abstract Chlorination of purine nucleosides protected with tert-butyldimethylsilyl (TBDMS) group was examined by the reaction of the C-8 lithiated species, generated by LDA, with p-toluenesulfonyl chloride as an electrophile. This provides a new method for the preparation of 8-chloropurine nucleosides. 相似文献
78.
Yumiko Kirihara Mayumi Takechi Kaoru Kurosaki Yuta Kobayashi Tsutomu Kurosawa 《Experimental Animals》2013,62(3):173-180
The combination of ketamine and xylazine is a widely used anesthetic for laboratory
animals. However, due to an abuse problem in Japan, ketamine has been specified as a
narcotic since 2007. Instead of using ketamine, Kawai et al. reported an
injectable formula with an equivalent effect to the mixture of ketamine and xylazine
[11]. The mixture of 0.3 mg/kg body weight (b.w.)
medetomidine (Med.), 4.0 mg/kg b.w. midazoram (Mid.), and 5.0 mg/kg b.w. butorphanol
(But.) produced an anesthetic duration of around 40 min in outbred ICR mice. However, the
anesthetic effect of the mixture for inbred mice strains remains unknown. Therefore, we
examined anesthetic effects of the mixture of Med., Mid., and But. in the BALB/c and
C57BL/6J strains. After intraperitoneal injection into mice, right front paw, left hind
paw, and tail pinch reflexes as well as corneal and righting reflexes were observed. Every
5 min, we scored each reflex category as 0 for reaction or 1 for no reaction. As long as
the total score was at least 4 out of 5, we considered the mixture as putting a mouse in a
surgical anesthetic state. The mixture produced an anesthetic duration of more than 45 min
in both strains of mice. These results indicate that the mixture of Med., Mid., and But.
can be a useful and effective anesthesia for the BALB/c and C57BL/6J strains of inbred
mice as well as outbred ICR mice. 相似文献
79.
Kentaro Uchida Kouji Naruse Masashi Satoh Kenji Onuma Masaki Ueno Shotaro Takano Ken Urabe Masashi Takaso 《Experimental Animals》2013,62(3):255-265
Although recent studies suggest that hyperlipidemia is a risk factor for osteoarthritis
(OA), the link between OA and hyperlipidemia is not fully understood. As the number of
activated, circulating myeloid cells is increased during hyperlipidemia, we speculate that
myeloid cells contribute to the pathology of OA. Here, we characterized myeloid cells in
STR/Ort mice, a murine osteoarthritis model, under hyperlipidemic conditions. Ratios of
myeloid cells in bone marrow, the spleen, and peripheral blood were determined by flow
cytometry. To examine the influence of the hematopoietic environment, including abnormal
stem cells, on the hematopoietic profile of STR/Ort mice, bone marrow transplantations
were performed. The relationship between hyperlipidemia and abnormal hematopoiesis was
examined by evaluating biochemical parameters and spleen weight of F2 animals
(STR/Ort x C57BL/6J). In STR/Ort mice, the ratio of CD11b+Gr1+ cells
in spleens and peripheral blood was increased, and CD11b+Gr1+ cells
were also present in synovial tissue. Splenomegaly was observed and correlated with the
ratio of CD11b+Gr1+ cells. When bone marrow from GFP-expressing mice
was transplanted into STR/Ort mice, no difference in the percentage of
CD11b+Gr1+ cells was observed between transplanted and age-matched
STR/Ort mice. Analysis of biochemical parameters in F2 mice showed that spleen
weight correlated with serum total cholesterol. These results suggest that the increase in
circulating and splenic CD11b+Gr1+ cells in STR/Ort mice originates
from hypercholesterolemia. Further investigation of the function of
CD11b+Gr1+ cells in synovial tissue may reveal the pathology of OA
in STR/Ort mice. 相似文献
80.
Shoichi Fujita Issei Chiba Mayumi Ishizuka Hidenobu Hoshi Hisato Iwata Akihito Sakakibara 《Biomarkers》2013,18(1):19-25
The impact of environmental pollution on selected animals was tested by monitoring the hepatic content of cytochromes P450 and their enzyme activities or by calculating TEQ values from the concentration of pollutants in the body. Fish-eating Stellars Sea Eagles, Haliaeetus pelagicus, found dead in the northern part of Hokkaido island accumulated high levels of PCBs and DDT and metabolites. The TEQ values calculated from the PCB concentration in the eagles were high enough to cause a significant toxic effect in other birds living in the same environment. Some of these birds were also contaminated with high concentrations of lead. Spotted seals, Phoca largha, captured along the coast-line of Hokkaido accumulated PCBs in their fat at about 100 million times the concentrations in the surface sea water. The levels of expressions of hepatic microsomal CYP 1A1and related enzyme activities in these seals showed good correlation to the levels of PCBs accumulated in the fat. The fresh water crabs, Eriocheir japonicus, were captured from three different rivers with various degrees of pollution. The P450 content and the related enzyme activities showed good correlation to TEQ values obtained from the concentrations of PCBs and PCDDs in the crabs from the rivers. The wild rodents, Clethrionomys rufocanus, were captured from urban, agricultural, and forest areas in Hokkaido. Those from the forest area had the lowest CYP content and related enzyme activities, comparable to those in laboratory-raised animals. Those from the urban areas, presumably contaminated with PAHs from fuel combustion, showed increased CYP 1A1 content and related enzyme activities. Those from the agricultural areas showed increased levels of CYP 1A1, 2B, 2E1. Rats treated with some of the agrochemicals used in the area resulted in a similar pattern of induction. It is concluded that P450 can be a useful biomarker for assessing the environmental impact of chemical pollutants on wild animals. 相似文献