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121.
Arikata M Itoh Y Okamatsu M Maeda T Shiina T Tanaka K Suzuki S Nakayama M Sakoda Y Ishigaki H Takada A Ishida H Soda K Pham VL Tsuchiya H Nakamura S Torii R Shimizu T Inoko H Ohkubo I Kida H Ogasawara K 《PloS one》2012,7(5):e37220
We made an H1N1 vaccine candidate from a virus library consisting of 144 (?=?16 HA×9 NA) non-pathogenic influenza A viruses and examined its protective effects against a pandemic (2009) H1N1 strain using immunologically na?ve cynomolgus macaques to exclude preexisting immunity and to employ a preclinical study since preexisting immunity in humans previously vaccinated or infected with influenza virus might make comparison of vaccine efficacy difficult. Furthermore, macaques carrying a major histocompatibility complex class I molecule, Mafa-A1*052:02, were used to analyze peptide-specific CD8(+) T cell responses. Sera of macaques immunized with an inactivated whole particle formulation without addition of an adjuvant showed higher neutralization titers against the vaccine strain A/Hokkaido/2/1981 (H1N1) than did sera of macaques immunized with a split formulation. Neutralization activities against the pandemic strain A/Narita/1/2009 (H1N1) in sera of macaques immunized twice with the split vaccine reached levels similar to those in sera of macaques immunized once with the whole particle vaccine. After inoculation with the pandemic virus, the virus was detected in nasal samples of unvaccinated macaques for 6 days after infection and for 2.67 days and 5.33 days on average in macaques vaccinated with the whole particle vaccine and the split vaccine, respectively. After the challenge infection, recall neutralizing antibody responses against the pandemic virus and CD8(+) T cell responses specific for nucleoprotein peptide NP262-270 bound to Mafa-A1*052:02 in macaques vaccinated with the whole particle vaccine were observed more promptly or more vigorously than those in macaques vaccinated with the split vaccine. These findings demonstrated that the vaccine derived from our virus library was effective for pandemic virus infection in macaques and that the whole particle vaccine conferred more effective memory and broader cross-reactive immune responses to macaques against pandemic influenza virus infection than did the split vaccine. 相似文献
122.
123.
Makoto Moro Ryuzo Torii Hajime Ishii Yoshikuni Tanioka Yoichi Inada Masami Kojima Hirotada Tsujii 《Primates; journal of primatology》2001,42(4):375-390
We investigated the relationship between the menstrual cycle and hormone levels in cynomolgus monkeys, and developed a sulpiride-induced
hyperprolactinemic anovulation model. On this study, we demonstrated the usefulness of the commercial human prolactin immunoradiometric
assay kit for the measurement of cynomolgus monkey serum samples. In the normal menstrual cycle of the cynomolgus monkey,
serum prolactin concentrations were not significantly different between luteal and follicular phases. However, the serum prolactin
concentration tended to elevate at the ovulation stage. And serum progesterone began to increase after an estradiol surge,
and then declined before the ensuing preovulatory rise in estradiol. During the luteal phase, the serum concentration of progesterone
was elevated. Moreover, we aimed to develop an anovulation model, using sulpiride-induced hyperprolactinemia in the cynomolgus
monkey. The serum prolactin level gradually increased during the twice-daily administration of sulpiride, and the drug produced
as big a response at 5 mg/kg. In this study, the length of the menstrual cycle was approximately 29 days in normal cynomolgus
monkeys. When treatment with sulpiride had been continued for more than one month, serum progesterone and estradiol levels
fell to within the range seen in the follicular phase of the normal cycle, and the absence of ovulation was recognized by
laparoscopy. Moreover, in this period we found that amenorrhea or anovulatory menstruation in the experimental animals. We
could produce an anovulatory model induced by sulpiride repeatedly administered over a long time period. Our findings suggest
that the cynomolgus monkey is useful as a endocrinological model that uses prolactin as a parameter and as an anovulatory
model; thus, it could be a useful model for the hyperprolactinemic amenorrhea and/or anovulation seen in humans. 相似文献
124.
Fumihiko Sato Asahi Ito Takashi Ishida Fumiko Mori Hisashi Takino Atsushi Inagaki Masaki Ri Shigeru Kusumoto Hirokazu Komatsu Shinsuke Iida Noriko Okada Hiroshi Inagaki Ryuzo Ueda 《Cancer immunology, immunotherapy : CII》2010,59(12):1791-1800
Engineering the Fc region of monoclonal antibodies (mAb) in order to enhance effector functions such as antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity (CDC) is likely to a be promising approach for next-generation mAb therapy. Here, we report on such an antibody, 113F, a novel CDC-enhancing variant of rituximab, and determine the tumor-associated factors influencing susceptibility to 113F-induced CDC. The latter included the quantity of complement inhibitors present, such as CD55 and CD59. We report that compared to rituximab, 113F mediated highly enhanced CDC against primary CD20-expressing lymphoma cells in vitro. Currently, a major problem in the field of immunotherapy research is the lack of suitable small animal models to evaluate human CDC in vivo. Therefore, we established a novel human tumor-bearing NOD/Shi-scid, IL-2Rγnull mouse model, in which human complement functions as the CDC mediator. We demonstrated that rituximab exerted significant antitumor effects via human CDC in this humanized mouse. The finding of specific localization of human C1q on CD20-expressing tumor cell membranes was consistent with the observation that human CDC indeed contributed to the antitumor effect in this model. Moreover, 113F exerted significantly more potent antitumor effects than rituximab in this in vivo model. The detection of more abundant dense signals from C1q using 113F compared to rituximab was consistent with the concept that this reagent represented a CDC-enhancing mAb. In the near future, the efficacy of this type of CDC-enhancing antibody will be determined in clinical trials in humans. 相似文献
125.
Active integration: new strategies for transgenesis 总被引:2,自引:0,他引:2
Shinohara ET Kaminski JM Segal DJ Pelczar P Kolhe R Ryan T Coates CJ Fraser MJ Handler AM Yanagimachi R Moisyadi S 《Transgenic research》2007,16(3):333-339
This paper presents novel methods for producing transgenic animals, with a further emphasis on how these techniques may someday
be applied in gene therapy. There are several passive methods for transgenesis, such as pronuclear microinjection (PNI) and
Intracytoplasmic Sperm Injection-Mediated Transgenesis (ICSI-Tr), which rely on the repair mechanisms of the host for transgene
(tg) insertion. ICSI-Tr has been shown to be an effective means of creating transgenic animals with a transfection efficiency
of approximately 45% of animals born. Furthermore, because this involves the injection of the transgene into the cytoplasm
of oocytes during fertilization, limited mosaicism has traditionally occurred using this technique. Current active transgenesis
techniques involve the use of viruses, such as disarmed retroviruses which can insert genes into the host genome. However,
these methods are limited by the size of the sequence that can be inserted, high embryo mortality, and randomness of insertion.
A novel active method has been developed which combines ICSI-Tr with recombinases or transposases to increase transfection
efficiency. This technique has been termed “Active Transgenesis” to imply that the tg is inserted into the host genome by enzymes supplied into the oocyte during tg introduction. DNA based methods alleviate many of the costs and time associated with purifying enzyme. Further studies have
shown that RNA can be used for the transposase source. Using RNA may prevent problems with continued transposase activity
that can occur if a DNA transposase is integrated into the host genome. At present piggyBac is the most effective transposon for stable integration in mammalian systems and as further studies are done to elucidate
modifications which improve piggyBac’s specificity and efficacy, efficiency in creating transgenic animals should improve further. Subsequently, these methods
may someday be used for gene therapy in humans. 相似文献
126.
Laparoscopic observations of morphological changes of the ovary during the ovarian cycle in conjunction with radioimmunoassay
of serum progesterone and estradiol-17β was investigated as a method of monitoring the ovarian cycle in the common marmoset.
In the common marmoset, plural follicles first appeared in each ovary five days prior to ovulation. At three to four days
prior to ovulation one or two follicles developed into translucent blisters on the surface of the ovary. As the follicles
filled with follicular fluid, they became larger and clearer until one to two days prior to ovulation, at which time they
formed well defined, transparent bubbles protruding from the surface of the ovary. After ovulation, the ovulation point could
be detected at the center of the follicle, sometimes surrounded by a corpus of engorged blood vessels. Ovulations of the plural
follicles were not simultaneous, and due to the time lag ovulations took at least 12 to 20 hrs in four out of seven animals
examined. After two to five days of ovulation the corpus hemorragicum, a bright red protrusion made of tissue and blood disrupted
by ovulation, was found. Subsequently, the color of the formatted corpus luteum changed from dark-red to yellow then to yellow
white. While the corpus luteum remained reddish in color serum progesterone was maintained at as high levels as in the luteal
phase.
There was no mature follicle or corpus luteum in subordinate female ovaries. 相似文献
127.
Ryuzo Fukao 《Ichthyological Research》1990,37(2):116-126
All the fish specimens ofNeoclinus bryope species complex collected from Okinawa Island including the 2 specimens already reported asN. bryope are referable toN. okazakii. Neoclinus nudus, hitherto known only from Taiwan, is newly recorded from Okinawa Island. These two species are redescribed on the basis of
the specimens from Okinawa Island. The specimens from Okinawa are compared with those from Shirahama in the case ofN. okazakii and with specimens from Taiwan as well asN. lacunicola andN. toshimaensis specimens from Shirahama in the case ofN. nudus. The habitats ofN. okazakii andN. nudus are clearly separated in the waters of Heshikiya, Okinawa Island and the habitat of either species is rather particular in
that it is exceptionally unoccupied by blenniids which are flourishing in the coastal waters of the Okinawa Islands. 相似文献
128.
Hayashi Ryuzo; Morikawa Hiromichi; Nakajima Norihiko; Ichikawa Yoshiaki; Senda Mitsugi 《Plant & cell physiology》1980,21(6):999-1005
Polarized infrared absorption spectra of film specimens of theepidermal cell wall of the third internode of pea stems wererecorded before and after treatment with endopolygalacturonase(endo-PG) and endo-pectin lyase (endo-PL). The spectra showedthat the pectic polysaccharides solubilized with endo-PG wereessentially the same as those solubilized with endo-PL. Thedegree of esterification of the pectic polysaccharides was about20%, and their major sugar components were uronic acids (32.8%),arabinose (48.1%) and galactose (19.2%). The polarized infraredspectra showed that pectic polysaccharides have an orientedstructure in cell walls with their molecular chains orientedpreferentially parallel to the direction of cell elongation.
1Present address: Research and Development, Kanzaki Paper Mfg.Co., Ltd., Amagasaki, Hyogo 660, Japan.
2Present address: Wakayama Research Laboratories, Kao Soap Co.,Ltd., Wakayama 640-91, Japan. (Received June 28, 1980; ) 相似文献
129.
Masao Nakagaki Ryuzo Takei Eiichi Nagashima Toshinobu Yaginuma 《Development genes and evolution》1991,200(4):223-229
Summary In the silkworm, Bombyx mori, diapause occurs at a specific embryonic stage, i.e. after formation of the germ band with cephalic lobes and telson and sequential mesoderm segmentation. As long as the eggs are incubated at 25° C, cell divisions and morphological development of the embryos cease. To examine changes in percentage of embryonic cells in the G1, S and G2 phases during embryogenesis, nuclear fractions were isolated from embryos, stained with propidium iodide and then subjected to flow cytometric analysis. The percentages of embryonic cells in G1, S and G2 were 10, 35 and 55%, respectively, at the stage of formation of cephalic lobes, whilst 98% of cells were in G2 at diapause stage. After termination of diapause by acclimation at 5° C or by a combination of chilling and HCl, cell division resumed in the embryos. During this period, the cells rapidly entered S phase through G1 from G2, suggesting that their G1 phase was short. In eggs in which diapause was averted by HCl-treatment after incubation at 25° C for 20 h after oviposition, embryonic development proceeded continuously for 9.5 days at 25° C until hatching. Along with this development, the G1 fraction increased to levels of about 90%. These results indicate that embryonic cells are arrested in G2 at diapause and suggest that, concomitant with further embryonic development, cell cycles become slower in proportion to an increasing length of G1. Finally, most of the cells may be arrested in G1, while there is only a small fraction of cells continuously cycling.
Offprint requests to: T. Yaginuma 相似文献
130.
Cellular analysis on localization of lens forming potency in the newt iris epithelium 总被引:4,自引:1,他引:3
The localization of a lens forming potency in the iris epithelium was studied by autoradiographic analysis of the distribution of 3H-thymidine labelled cells to be participated in lens regeneration in newts. DNA synthesis started from the dorsal portion of the iris epithelium around 4 days after lentectomy. 5 days after lentectomy, a large number of labelled cells were mostly found in the dorsal sector, showing strong contrast to the ventral and lateral sectors of iris, which contained a few labelled cells. The labelled index (the number of labelled cells/the number of cells in the definite pigmented area of the iris epithelium) of the dorsal sector attained the highest value, 29.7 ± 2.35, on day 7 after lentectomy, and dropped temporarily. This was followed by the second peak on day 12. The dorso-ventral ratio of the labelled index reached to the highest value, 6.87 ± 0.67, on day 5. This ratio decreased rapidly after the completion of a lens rudiment, and it became about 1. In “chase” experiments by diluting the radio-isotope with excess cold thymidine, it was obviously shown that most of the cells labelled with the radio-isotope and distributed in the dorsal marginal iris 5 days after lentectomy participated in the formation of a lens regenerate during the period of chasing. From these results, the following conclusion was drawn. The iris epithelium consists of at least 2 different cell populations; one is capable of transformation into lens cells and is distributed mostly in the dorsal portion of the iris epithelium, while the other has no potency for transformation and is able to grow to compensate a loss of the dorsal marginal cells which transformed into lens cells during the process of lens regeneration. 相似文献