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1.
E T Iwamoto 《Life sciences》1988,43(6):503-508
Intracerebroventricular (i.c.v.) administration of dynorphin A [1-17] induced significant place preference conditioning in male, Sprague-Dawley rats. Place preferences were induced by 2.3 and 3.5 nmole, but not 1.2 nmole of dynorphin A. Co-administration of naloxone, 27.5 nmole but not 5.5 nmole, antagonized the reward response induced by 2.3 nmole of dynorphin A. Leu-enkephalin, 5 or 25 nmole, and dynorphin A [2-17], 2.3 or 3.5 nmole, had no effect in the place conditioning paradigm. 相似文献
2.
Charles Romeo Naoko Moriwaki Kerry T. Yasunobu Irwin C. Gunsalus Hideo Koga 《Journal of Protein Chemistry》1987,6(3):253-261
The first 12 NH2-terminal amino acids of the Pseudomonas putida putidaredoxin reductase were shown to be Met-Asn-Ala-Asn-Asp-Asn-Val-Val-Ile-Val-Gly-Thr. Comparison of these data with the DNA sequence of the BamHI-HindIII 197-base fragment derived from the PstI 2.2-kb fragment obtained from the P. putida plasmid showed that the putidaredoxin reductase gene was downstream from the cytochrome P-450 gene and the intergenic region had the 24-nucleotide sequence TAAACACATGGGAGTGCGTGCTAA. The Shine-Dalgarno sequence GGAG was detected in this region. The initiating triplet for the reductase gene was GTG, which normally codes for valine, but in the initiating codon position codes for methionine. From the amino acid sequence and X-ray data comparisons with other flavoproteins, what appears to be the AMP binding region of the FAD can be recognized in the NH2-terminal portion of the reductase involving residues 5–35.This article was presented during the proceedings of the International Conference on Macromolecular Structure and Function, held at the National Defence Medical College, Tokorozawa, Japan, December 1985. 相似文献
3.
Kenji Masumoto Tomoki Shono Shin-ichiro Takasugi Noboru Hotta Kazutaka Fujishima Yukihide Iwamoto 《Journal of electromyography and kinesiology》2007,17(5):596-604
This study aimed to examine whether walking in water produces age-related differences in muscle activity, stride frequency (SF), and heart rate (HR) response. Surface electromyography (EMG) was used to evaluate muscle activities in six older and six young subjects while they walked in water immersed to the level of the xiphoid process. The trials in water utilized the Flowmill which consists of a treadmill at the base of a water flume. The measurement of maximal voluntary contraction (MVC) of each muscle was made prior to the gait analysis. The %MVCs, which refer to the surface EMG measures, from the gastrocnemius of the older subjects were significantly lower than those of the young subjects, in every experimental condition (P<0.05). In contrast, the %MVCs from the rectus femoris (P<0.05) and the biceps femoris (P<0.001) of older subjects were significantly greater than those of young subjects in every experimental condition. Moreover, the SFs of older subjects were also significantly greater than those of young subjects (P<0.05), while the HR responses of older and young subjects were similar. In conclusion, the older subjects had increased hip musculature activity and decreased ankle plantar flexor activity while walking in water, compared with the young subjects. 相似文献
4.
F Nagase K Ueda K Kawashima S M Jamshedur Rahman K Isobe T Yoshida Y Hasegawa K Ando T Iwamoto E Nagura 《Journal of immunology (Baltimore, Md. : 1950)》1987,138(7):2359-2365
When a murine leukemia L1210-specific Lyt-2+ T cell clone, K7L, was injected i.p. into CD2F1 mice together with L1210, the normal growth of L1210 in the peritoneal cavity of the mice at the early stage (days 0 to 5) was strongly inhibited, but L1210 grew progressively at the middle-stage (days 5 to 10), and then was rejected at the late stage (days 10 to 20). The mice thus survived for long times (more than 60 days), whereas the normal control injected with L1210 alone died within 14 days. The L1210 that grew at the middle stage in mice initially inoculated with L1210 together with K7L was a K7L-insensitive (K7L-) variant. All of eight tumor clones established from L1210-K7L- by limiting dilution was insensitive to the antitumor activity of K7L, and this property of tumor clones was stable after repeated in vitro passage. The initial depression of the L1210 growth by K7L followed by growth and rejection of the variant L1210-K7L- by the host T cell activity was then found to prepare a strong, long-lasting (more than 3 mo) immunity to protect mice against the high-dose (10(7) cells per mouse) challenge of original L1210. Corresponding to this result, definite tumor (L1210)-specific cytotoxic T lymphocyte (CTL) activity against both variant and original L1210 targets was developed by antigen (L1210) restimulation in the culture of spleen cells from these mice, but was not increased to a detectable level before L1210-K7L- variant started to grow. It was suggested that the 1210-K7L- variant and the original L1210 should have the common tumor-specific antigen that was independent of the K7L-reactive antigen, and that original L1210, whose growth was retarded by K7L, primed the host with the common antigen to be enormously boosted by the subsequently growing L1210-K7L- variant. 相似文献
5.
Serum C-peptide responses to glucagon and daily urine C-peptide excretion in successive periods of different treatment in two groups of patients with non-insulin-dependent diabetes mellitus (NIDDM) (mean interval between two tests less than 1 month) were compared. In group A patients (n = 8), the glycemic control was improved after transferring the treatment from sulfonylurea (SU) to insulin (fasting plasma glucose: SU: 192 +/- 47, insulin: 127 +/- 21 mg/dl, mean +/- S.D., p less than 0.01). Fasting serum C-peptide immunoreactivity (CPR) was significantly lower at the period of insulin treatment (SU: 1.93 +/- 1.01, insulin: 1.47 +/- 0.79 ng/ml, p less than 0.05), but there was no difference in the increase in serum CPR (maximal--fasting) (delta serum CPR) during glucagon stimulation in the two periods of treatment (SU: 1.70 +/- 0.72, insulin: 1.47 +/- 0.98 ng/ml). In group B patients (n = 7), there was no significant difference in glycemic control after transferring the treatment from insulin to SU (fasting plasma glucose: insulin: 127 +/- 24, SU: 103 +/- 13 mg/dl). Fasting serum CPR was significantly lower during the period of insulin treatment (insulin: 1.39 +/- 0.64, SU: 2.21 +/- 0.86 ng/ml, p less than 0.025), but delta serum CPR during glucagon stimulation still showed no significant difference between the two periods (insulin: 1.97 +/- 1.16, SU: 2.33 +/- 1.57 ng/ml).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
6.
K Iwamoto M Takeishi K Takagi T Kuyama M Yukawa M Ishida T Kuramochi 《Cellular and molecular biology, including cyto-enzymology》1989,35(3):271-278
The murine monoclonal antibodies RPA-T4 and HuLy-m8, specific for a framework determinant of human helper/inducer and suppressor/cytotoxic T cell antigens, cross-reacted with canine cell membrane molecules recognizing a biomolecular complex (50,000 to 55,000 daltons) similar to that described in humans. We investigated the distribution of these helper and suppressor T cell-like antigens on canine peripheral blood lymphocytes. With complement-mediated lymphocytotoxicity, 34% and 35% of the canine lymphocytes expressed the helper T cell-like antigens and the suppressor-like T cell antigens, respectively. When the lymphocytes were treated with RPA-T4 and HuLy-m8, the respective helper and suppressor function was significantly inhibited. 相似文献
7.
Induction and characterization of minor histocompatibility antigens. Specific primary cytotoxic T lymphocyte responses in vitro 总被引:1,自引:0,他引:1
K Ando I Nakashima F Nagase K Isobe K Kawashima Y Hasegawa T Yoshida T Iwamoto T Hasegawa Y Muro 《Journal of immunology (Baltimore, Md. : 1950)》1988,140(3):723-729
A definite cytotoxic activity was developed in a BALB/c (H-2d) anti-DBA/2 primary mixed leukocyte culture (MLC), which received interleukin 2 (IL-2) on day 3 of culture. This cytotoxic activity was minor histocompatibility antigens (MIHA)-specific at the stimulator level, and was not developed in a syngeneic (BALB/c anti-BALB/c) MLC. The addition of IL-2 on day 3 of culture was crucial; no or very weak cytotoxic activity was developed in MLC receiving IL-2 on day 0 or on both day 0 and day 3. Only appropriate MIHA-allogeneic tumor cells were lysed as the target of the cytotoxic activity. The cytotoxic activity seemed MIHA-specific also at the target level; it lysed tumor cells of DBA/2 mouse origin but not those of BALB/c (syngeneic) origin. Phenotypes of the cytotoxic effector cell were Thy-1+ Lyt-2+. We concluded from these results that MIHA-specific cytotoxic T lymphocytes (CTL) were generated in the MIHA-allogeneic primary MLC. In this newly developed system, we studied genetic and antigenic requirements for primary anti-MIHA CTL responses in vitro. We demonstrated; among spleen cells (SC) of seven B10 H-2-congenic strains only SC of B10.D2 strain whose major histocompatibility complex (MHC) (H-2d) was compatible with the responder MHC effectively stimulated responder BALB/c (H-2d) SC for an anti-MIHA (DBA-C57BL-common) CTL response. Similarly, only SC of two out of seven C x B recombinant inbred strains (C x B.H and C x B.D), which were compatible at the MHC with responder SC, activated responder BALB/c SC for the response. The possibility that cells responding to H-2 alloantigens suppressed the anti-MIHA response was ruled out. Additional experiments showed that compatibility at the H-2K-end or the H-2D-end of the MHC was sufficient for a definite anti-MIHA response. These provided formal evidence that primary anti-MIHA CTL responses in vitro were MHC-restricted at the stimulator level. We then showed that sonication-disrupted SC or Sephadex G-10 column-passed nonadherent SC failed to stimulate responder SC for a primary anti-MIHA CTL response, whereas G-10-passed nonadherent SC responded well to adherent stimulator cells. Further study demonstrated that Ia+ adherent cells were the most active cell type as stimulator. Finally, we confirmed that the primary anti-MIHA CTL responses to adherent stimulator cells was MHC-restricted. 相似文献
8.
Complete nucleotide sequence of the mitochondrial DNA from a liverwort,Marchantia polymorpha 总被引:1,自引:1,他引:0
Kenji Oda Katsuyuki Yamato Eiji Ohta Yasukazu Nakamura Miho Takemura Naoko Nozato Kinya Akashi Takeshi Kanegae Yutaka Ogura Takayuki Kohchi Kanji Ohyama 《Plant Molecular Biology Reporter》1992,10(2):105-163
Libraries of cosmid and plasmid clones covering the entire region of mtDNA from the liverwortMarchantia polymorpha were constructed. These clones were used for the determination of the complete nucleotide sequence of the liverwort mtDNA
totally 186,608 bp (GenBank no. M68929) and including genes for 3 species of ribosomal RNAs, 29 genes for 27 species of transfer
RNAs, and 30 genes for functionally known proteins (16 ribosomal proteins, 3 subunits of cytochromec oxidase, apocytochromeb protein, 3 subunits of H+-ATPase, and 7 subunits of NADH ubiquinone oxidoreductase). The genome also contains 32 unidentified open reading frames.
Thus the complete nucleotide sequences from both chloroplast and mitochondrial genomes have been determined in the same organism.
Plasmid clones are available upon the request.
Gene names are represented according to Lonsdale and Leaver (1988) with modifications recommended by Lonsdale (personal communication). 相似文献
9.
K Yoshino S Kawagishi M Iwamoto N Amano 《Nihon seirigaku zasshi. Journal of the Physiological Society of Japan》1991,53(6):207-215
We developed a method for a determination of the amount of retrogradely transported HRP in the rat masseteric motoneuron using a modification of Mesulam's HRP histochemical protocol and an image processing system combined with a light microscope and a television camera. To test the validity and reproducibility of the new method, a quantitative comparison of the amount of dark blue granules of HRP-product in the cell body of masseteric motor neurons was performed between the right and left trigeminal motor nuclei of 70 rats, which resulted in no significant difference. An additional study used the method was made of the effects of administration of five dopamine receptor antagonists with different biochemical and pharmacologic properties on retrograde transport of HRP in the rat masseteric motoneuron. As a result, chlorpromazine, haloperidol, SCH 23390, and sulpiride significantly enhanced retrograde transport of HRP as against domperidone which showed no significant change in the transport. A possible regulatory system for retrograde transport of HRP in the masseteric motoneuron was discussed in relation to the action of the dopamine receptor. 相似文献
10.
Tomizawa Ken-ichi; Ito Naoko; Komeda Yoshibumi; Uyeda Taro Q. P.; Takio Koji; Furuya Masaki 《Plant & cell physiology》1991,32(1):95-102
The pea phytochrome I (PI) cDNA clone, pPP1001, was expressedin E. coli. The plasmid pPP1001 contains pea PI cDNA which coversthe entire coding region with the Shine-Dalgarno consensus sequencejoined upstream of the cDNA in an expression vector pNUT6. ThepPP1001 transformants formed typical inclusion bodies when culturedat 32?C. However, when cultured at 37?C or in the presence ofisopropyl-ß-D-thiogalactopyranoside (IPTG) at 32?C,the bacteria lysed before inclusion body formation. Immuno-stainingwith anti-PI monoclonal antibody, mAP5, of transformants fixedby cold methanol showed that stainable materials were distributedin whole cytoplasmic region. When the inclusion bodies wereobserved clearly, the regions corresponding to the inclusionbodies became difficult to stain. Western blot analysis, however,showed that a ca. 100 kDa PI polypeptide was detected in thefraction from inclusion bodies and a ca. 90 kDa PI polypeptidefrom the soluble fraction. The amino acid sequence analysisof purified 100 kDa PI sample indicated that its amino terminusis blocked. However, minor signals in one experiment yieldeda sequence corresponding to the expected amino terminus of peaPI except for the initiation methionine. One of the anti-peaPI monoclonal antibodies, mAP9, that recognizes the near N-terminusof pea phytochrome was reactive to the 100 kDa polypeptide. (Received June 22, 1990; Accepted November 18, 1990) 相似文献