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951.
G Komaki H Tamai K Kiyohara O Fukino T Nakagawa S Mori L F Kumagai S Nagataki 《Endocrinologia japonica》1986,33(3):303-308
We investigated changes in the hypothalamic-pituitary-thyroid axis before, during, and after fasting in twenty-one non-obese euthyroid patients with psychosomatic diseases. Blood samples for free T3 (FT3), T3, free T4 (FT4), T4, reverse T3 (rT3), and TSH were obtained from all patients before and on the 5th day of fasting, and in 11 of the same individuals on the 5th day of refeeding. Serum TSH and T3 responses to TRH were also evaluated in 10 patients before and on the 5th day of fasting. During the fast, FT3, T3 and TSH levels decreased significantly and rT3 levels increased significantly whereas FT4 and T4 levels remained within the normal range. Maximal delta TSH, peak TSH levels, max delta T3, peak T3 levels, and net secretory responses to TRH decreased significantly. Peak TSH levels and max delta TSH to TRH correlated well with basal levels of TSH. A statistically significant negative correlation between basal levels of FT4 and TSH was observed. After refeeding, there was a significant increase only in TSH which returned to prefasting values. These results demonstrated that in a state of "low T3" during acute starvation a reduction in serum T3 might depend partly on TSH-mediated thyroidal secretion. 相似文献
952.
Takaaki Tanaka Keiichi Yamamoto Sirintornthep Towprayoon Hiroki Nakajima Kenji Sonomoto Kenzo Yokozeki Koji Kubota Atsuo Tanaka 《Applied microbiology and biotechnology》1989,30(6):564-568
Summary Auxotrophic mutant cells of Corynebacterium glycinophilum with high l-serine production activity were immobilized by entrapment with various gel materials, such as synthetic prepolymers and natural polysaccharides. The entrapped cells were used for estimation of l-serine productivity in a medium supplemented with glycine as a precursor. Based on the above criteria, including cell growth in gels and cell leakage from gels, calcium alginate was the most suitable gel material. Continuous l-serine fermentation with calcium alginate-entrapped growing cells was successfully achieved in an air-bubbled reactor for at least 13 days. 相似文献
953.
A new triggerfish,Rhinecanthus abyssus, is described from three specimens collected in the Ryukyu Islands at depths of 120–150 m. It is distinguished from the other species ofRhine-canthus by the combination of the following characters: soft dorsal rays 22–23, soft anal rays 20, a large black blotch around anus, and no semicircular white band on posterior side of body. 相似文献
954.
Masaki Nakanishi Norimichi Kan Takashi Okino Kohei Satoh Keiichi Mise Yasufumi Teramura Seiji Yamasaki Kazuhisa Ohgaki Takayoshi Tobe 《Biotherapy》1990,2(1):21-32
Peripheral blood lymphocytes, regional lymph node lymphocytes or malignant effusion lymphocytes from cancer patients were incubated with crude IL-2 (cIL-2) for 13 days. These effectors, which frequently expressed IL-2 receptor (IL-2R), proliferated well and possessed augmented killing activity against fresh autologous tumor cells and K562. However, when recombinant IL-2 (rIL-2) was added for the last 4 days of culture instead of cIL-2, IL-2R expression and killing activity against fresh autologous tumor cells decreased significantly (P<0.05). Phenotypic analysis indicated that cIL-2 significantly promoted the expansion of the cytotoxic population (CD8+ .11b–)(P<0.05). The decreases in killing activity and IL-2R expression were restored by 0.004% PHA plus rIL-2, but not in the presence of rIFN-, rIL-1, rIL-l, rIL-4 or rIL-6. PHA-free cIL-2 maintained killing activity, but not IL-2R expression.We conclude that some factors in cIL-2 and a low dose of PHA-P are necessary for the maintenance of killing activity and IL-2R expression of cultured lymphocytes in the late phase of culture. 相似文献
955.
Norimichi Kan Takashi Okino Masaki Nakanishi Kohei Sato Keiichi Mise Seiji Yamasaki Yasufumi Teramura Kazuhisa Ohgaki Takayoshi Tobe 《Biotherapy》1989,1(3):197-206
BALB/c mice inoculated IP with a syngeneic plasmacytoma MOPC104E were treated with a combination of a streptococcal preparation, OK-432 (1 KE, 0.1 mg/mouse), low-dose of cyclophosphamide (CPA, 1 mg/kg) and adoptive transfer of tumor-bearer-spleen cells (2 x 10(7) cells) cultured with IL2 and sonicated tumor extract (adoptive immunotherapy; AIT). The consecutive protocol of OK-432 (day 8, 9 post inoculation) - CPA (day 10) - AIT (day 11) was the most effective. Rate of complete remission was highest when recombinant (r-) IL2 was injected to the mice after AIT. Moreover, another bacterial preparation, Nocardia rubra cell wall skeleton and another low-dose chemotherapy, Mitomycin C could be used successfully instead of OK-432 or CPA. Transfer test of intraperitoneal cells (tumor cells plus host cells) of mice on day 11 post inoculation (on the day of AIT) revealed that OK-432 augmented the susceptibility of peritoneal cells to cultured lymphocytes in inhibition of transplantability, and that CPA after OK-432 augmented the anti-tumor effect of tumor-bearer-spleen cells which act synergistically with cultured lymphocytes. This therapy schedule seems to be the best model to augment the effect of AIT with minimal side effect. 相似文献
956.
957.
Takahiko Tanigawa Hisao Takayama Hitoshi Osatake Keiichi Tanaka Noriko Kasagi Yoshinori Tanaka 《Cytotechnology》1992,10(1):43-51
Characteristics of mouse macrophage (MP) cell lines A640-BB-2, J774.1 and P388D1 and mouse peritoneal exudate MPs were studied and compared in cell morphology, ability to recognize tumor cells in the presence and absence of OK-432 known to activate MPs, and in lysosomal enzyme activity. In A640-BB-2 cells and exudate MPs, cell surfaces showed a few ridge-like processes and microvilli; spontaneous cytotoxicity was moderate against tumor target L929, and little or absent against targets SV3T3, B-16 and U937; and lysosomal enzyme activity of nonspecific esterase, acid phosphatase, and -glucuronidase was high. After culture in the presence of OK-432, A640-BB-2 cells and exudate MPs showed more extensive spreading with larger surface areas and with increased numbers of ridge-like processes and microvilli, and their cytotoxicity against target L929 became more extensive. The stable soluble factor did not participate in the mechanism of cytotoxicity against target L929 mediated by A640-BB-2 cells and exudate MPs. J774.1 and P388D1 cells were different from exudate MPs in cell morphology and ability to recognize tumor cells when cultured either with or without OK-432, and in lysosomal enzyme activity. A640-BB-2 cells seem to be useful in studying MP-tumor cell interaction and MP activation, and in detecting the trace biological activating factor of MPs.Abbreviations DEM
Dulbecco's modified Eagle's medium
- MP
macrophage
- PBS
phosphate-buffered saline
- SEM
scanning electron microscopy 相似文献
958.
Katsuyuki Tamai Kiyohide Kojima Takamasa Hanaichi Shigeo Masaki Motoshi Suzuki Hayato Umekawa Shonen Yoshida 《Biochimica et Biophysica Acta (BBA) - Gene Structure and Expression》1988,950(3)
The DNA polymerase α-DNA primase complex was purified over 17 000-fold to near homogeneity from calf thymus using an immunoaffinity column. Sodium dodecyl sulfate gel electrophoresis revealed three polypeptides with molecular weights of 140, 50 and 47 kDa, in a ratio of 1:2:0.25. The complex showed a sedimentation coefficient of 9.7 S, a Stokes radius of 56 Å and a native molecular weight of 250–260 kDa. Taken together, the data suggest that the calf thymus dNA polymerase α-DNA primase complex is essentially a heterotrimer of large (140 kDa) and small (50 kDa) subunits in a ratio of 1:2, with a globular conformation. Electron-microscopic studies of the complex revealed a spherical particle of 120 Å in diameter, in agreement with the physicochemical results. The binding of the complex to DNA was also demonstrated. 相似文献
959.
Takayuki Aihara Toshiya Ito Yasuaki Yamanaka Keiichi Noguchi Masafumi Odaka Masae Sekine Hiroshi Homma Masafumi Yohda 《Extremophiles : life under extreme conditions》2016,20(4):385-393
Functional and structural characterizations of pyridoxal 5′-phosphate-independent aspartate racemase of the acidothermophilic archaeon Picrophilus torridus were performed. Picrophilus aspartate racemase exhibited high substrate specificity to aspartic acid. The optimal reaction temperature was 60 °C, which is almost the same as the optimal growth temperature. Reflecting the low pH in the cytosol, the optimal reaction pH of Picrophilus aspartate racemase was approximately 5.5. However, the activity at the putative cytosolic pH of 4.6 was approximately 6 times lower than that at the optimal pH of 5.5. The crystal structure of Picrophilus aspartate racemase was almost the same as that of other pyridoxal 5′-phosphate -independent aspartate racemases. In two molecules of the dimer, one molecule contained a tartaric acid molecule in the catalytic site; the structure of the other molecule was relatively flexible. Finally, we examined the intracellular existence of d-amino acids. Unexpectedly, the proportion of d-aspartate to total aspartate was not very high. In contrast, both d-proline and d-alanine were observed. Because Picrophilus aspartate racemase is highly specific to aspartate, other amino acid racemases might exist in Picrophilus torridus. 相似文献
960.
Satoshi Yamamoto Kenji Minami Keiichi Fukaya Kohji Takahashi Hideki Sawada Hiroaki Murakami Satsuki Tsuji Hiroki Hashizume Shou Kubonaga Tomoya Horiuchi Masamichi Hongo Jo Nishida Yuta Okugawa Ayaka Fujiwara Miho Fukuda Shunsuke Hidaka Keita W. Suzuki Masaki Miya Hitoshi Araki Hiroki Yamanaka Atsushi Maruyama Kazushi Miyashita Reiji Masuda Toshifumi Minamoto Michio Kondoh 《PloS one》2016,11(4)