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971.
Kanda Shinji Takeyama Hiromitsu Kikumoto Yoshikazu Morrison Sherrie L. Morton Donald L. Irie Reiko F. 《Cell biochemistry and biophysics》1994,24(1-3):65-74
Previously we developed a murine monoclonal anti-idiotype (antiid) antibody (4C10) that mimics the melanoma-associated ganglioside
antigen GM3, that is, it carries the internal image of GM3. 4C10 was made against the human monoclonal antibody (HuMAb) L612, which reacts with several types of human cancer cells,
including melanoma and breast cancer. To reduce mouse components of 4C10, the constant region was replaced by a human constant
domain to form the murine/human chimeric anti-id antibody TVE-1. In the present study, we sought to determine which chain
(VH or VL) of the anti-id is responsible for the antigenicity of GM3. The TVE-1 VH and VL expression vectors were simultaneously transfected with either the VH or VL expression vector of a murine-human chimeric IgG antidansyl haptenic antibody, resulting in the construction of three different
combinations of VH and VL chimeric antibodies. These IgG molecules were produced from the transfectomas, and their reactivity to HuMAb L612 was tested.
Neither of the IgG proteins that had cross-combined the VH-VL pair showed positive results, suggesting that both heavy and light chains are required to express the antigenicity. The in
vivo antigenicity of this chimeric anti-id was confirmed by skin tests in melanoma patients receiving active specific immuntherapy. 相似文献
972.
Multi-Gene Family of Major Surface Glycoproteins of Pneumocystis carinii: Full-Size cDNA Cloning and Expression 总被引:2,自引:0,他引:2
The major surface glycoprotein (MSG) of Pneumocystis cariniiplays a crucial role in the fatal pneumonia caused by this organismin AIDS patients. A cDNA encoding a full-length MSG polypeptidewas isolated from a phage library of rat-derived P. cariniicDNAs. The deduced MSG, referred to as the MSG5 subtype, isa 120,765-Da protein composed of 1,076 amino acids and containsan anchoring hydrophobic sequence at the C-terminus of the protein.Sequence analyses of cloned MSG-cDNAs revealed an MSG-gene familywith 70% protein sequence identity between subtypes. P. cariniikaryotype hybridization analyses indicated that the MSG genefamily members are scattered throughout most of the P. cariniichromosomes. These recombinant MSG proteins reacted with theantiserum from P. carinii-infected rats, as expected, and antiserumgenerated against P. carinii-infected mice, indicating the existenceof common determinants in MSG polypeptides. The family of MSGproteins is rich in cysteine residues and these cysteine arehighly conserved in all MSG subtypes regardless of species specificity,suggesting the structural and/or functional importance of thesecysteine. The pathobiological significance of the MSG gene familyand its sequence diversity in P. carinii is discussed. 相似文献
973.
974.
Peter Werckmeister Kôozôo Hayashi Yoshikazu Yasaki 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1966,36(5):233-235
Zusammenfassung Bei der diploiden hohen Garten-Iris cv. Floridor (Cayeux 1929) wurde als bisher einziger Sorte ein neues Delphinidinglycosid Floridorin aufgefunden. Seine chemische Konstitution wurde als Delphinidin-3-Glukose-Rhamnose-p-Cumarsäure aufgeklärt. Es fand sich zusammen mit dem schon von uns aufgeklärten Anthozyan Tulipanin (Delphinidin-3-Glucose-Rhamnose). Das Hauptanthozyan der anderen Garten-Iris ist das von uns neuerdings nachuntersuchte Violanin. Die Untersuchungen wurden mit bereits von uns angegebenen neueren Methoden ausgeführt, wie der stufenweisen Hydrolyse und dem oxidativen Abbau. Das neue Floridorin zeigte bei den diploiden Garten-Iris einen monohybriden rezessiven Erbgang gegen Violanin. Die Blüten der Sorten, die Floridorin enthalten, sind schon mit dem Auge an einem charakteristischen taubenblauen Farbton zu erkennen.
On the constitution and inheritance of a new delphinidine glycoside Floridorin from the cultivated iris variety cv. Floridor (Cayeux 1929)Studies on anthocyanins LI
Summary The diploid tall bearded garden Iris cv. Floridor (Cayeux 1929) proved to be thus far the only variety with a different anthocyanine, called Floridorin. Its chemical structure has been found to be delphinidine-3-glucose-rhamnose-p-coumaric-acid. It occurs together with tulipanine already analyzed by us as delphinidine-3-glucose-rhamnose. The main anthocyanine of thePogoniris garden varieties proved to be violanin the structure of which has been studied by us lately. The investigations were carried out by some newer methods, such as partial hydrolysis and oxidative degradation already published by us. The new Floridorin gives a monohybrid recessive Mendelian ratio with other diploid varieties ofPogoniris colored by violanine. The varieties colored by Floridorin show a characteristic greyish blue coloration which can be recognized with the naked eye.相似文献
975.
Water chestnut (genus Trapa) is an annual floating-leaved macrophyte that produces dense beds known to drastically modify freshwater ecosystems. Although Trapa displays a distinct phenology that should alter the innate seasonal dynamics of ecosystems, the seasonality of these effects has rarely been investigated. Therefore, we examined seasonal changes in physicochemical conditions and assemblages of zoobenthos and zooplankton, and whether these changes were correlated with the rise and decline of dense beds of Trapa japonica in Lake Mikata, a temperate shallow lake in central Japan. Our results suggested that the formation of dense Trapa beds during summer resulted in hypoxia, which significantly decreased the abundance of Chironomidae and Oligochaeta in the benthic community, as well as that of Calanoida among zooplankton. When dense Trapa beds formed, we also detected growth of other taxa that were resistant to hypoxia, including Cladocera, Cyclopoida, Ostracoda, and Nematoda. Chlorophyll a concentration declined across the lake during summer, when dense Trapa beds formed. The decline in Trapa beds from autumn to spring resulted in increased dissolved oxygen concentration, chlorophyll a concentration, and invertebrate abundance (Chironomidae, Oligochaeta and Calanoida), as well as a decrease in taxa utilizing the dense Trapa beds. Our results suggest that the phenology of dense Trapa beds can drastically change the seasonal dynamics of physicochemical conditions and the lower components of the food web in a shallow lake ecosystem. 相似文献
976.
Length–weight relationships for common juvenile fishes and prey species in Hawaiian estuaries
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K. A. Peyton T. S. Sakihara L. K. Nishiura T. T. Shindo T. E. Shimoda S. Hau A. Akiona K. Lorance 《Zeitschrift fur angewandte Ichthyologie》2016,32(3):499-502
Length–weight relationships (LWR) using 3876 individuals were determined for 39 species sampled in estuarine systems in the main Hawaiian Islands, including 33 species of fish from 21 families, five species of crustaceans (prey) from two families, and one mollusk species. For 17 species, LWRs were estimated for the first time. For another 14 species their LWRs were newly reported for Hawaiian waters, including seven introduced taxa that are well established in the islands' estuaries. The LWRs for all taxa include juvenile and sub‐adult size ranges commonly encountered in Hawaiian estuaries. 相似文献
977.
Morito Sakuma Yoshikazu Kumashiro Masamichi Nakayama Nobuyuki Tanaka Yuji Haraguchi Kazuo Umemura Tatsuya Shimizu Masayuki Yamato Teruo Okano 《Journal of visualized experiments : JoVE》2016,(109)
Thermoresponsive poly(N-isopropylacrylamide) (PIPAAm)-immobilized surfaces for controlling cell adhesion and detachment were fabricated by the Langmuir-Schaefer method. Amphiphilic block copolymers composed of polystyrene and PIPAAm (St-IPAAms) were synthesized by reversible addition-fragmentation chain transfer (RAFT) radical polymerization. A chloroform solution of St-IPAAm molecules was gently dropped into a Langmuir-trough apparatus, and both barriers of the apparatus were moved horizontally to compress the film to regulate its density. Then, the St-IPAAm Langmuir film was horizontally transferred onto a hydrophobically modified glass substrate by a surface-fixed device. Atomic force microscopy images clearly revealed nanoscale sea-island structures on the surface. The strength, rate, and quality of cell adhesion and detachment on the prepared surface were modulated by changes in temperature across the lower critical solution temperature range of PIPAAm molecules. In addition, a two-dimensional cell structure (cell sheet) was successfully recovered on the optimized surfaces. These unique PIPAAm surfaces may be useful for controlling the strength of cell adhesion and detachment. 相似文献
978.
Ayana Hasegawa Miwa Watanabe Hironari Osada Misato Ogawa Hikaru Ohno Nanako Yanuma Kazuaki Sasaki Minoru Shimoda Junsuke Shirai Keitaro Ohmori 《Biochemical and biophysical research communications》2018,495(3):2184-2188
A time-of-day-dependent variation in IgE-mediated passive systemic anaphylaxis was previously reported in ICR mice. In the present study, we investigated time-of-day-dependent variations in IgE-, histamine-, and platelet-activating factor (PAF)-mediated systemic anaphylaxis in C57BL/6, BALB/c, and NC/Nga mice at 9:00?h and 21:00?h, and evaluated the potential influence of glucocorticoids (GCs) on these variations. We found significant time-of-day-dependent variations in IgE-mediated systemic anaphylaxis in C57BL/6 mice, and in histamine- and PAF-mediated systemic anaphylaxis in BALB/c mice. Significant daily variations in IgE-, histamine-, and PAF-mediated systemic anaphylaxis were not observed in NC/Nga mice. Pretreatment with dexamethasone and adrenalectomy abolished the daily variations in IgE-mediated systemic anaphylaxis in C57BL/6 mice and in PAF-mediated systemic anaphylaxis in BALB/c mice, suggesting that GCs from adrenal glands are pivotal in regulating these variations. In contrast, pretreatment with dexamethasone and adrenalectomy did not abolish the daily variation in histamine-mediated systemic anaphylaxis in BALB/c mice, suggesting that GC-independent and adrenal gland-independent mechanisms are important for the variation. The present study demonstrated that time-of-day-dependent variations in systemic anaphylaxis differed among inbred mouse strains and with anaphylaxis-inducing substances. Thus, mouse strains, time of experiment, and anaphylaxis-inducing substances used must be considered to obtain appropriate experimental results. 相似文献
979.
980.