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991.
992.
993.
Kenichi Miyamoto Kanako Katai Sawako Tatsumi Kanako Sone Hiroko Segawa Kazumi Takada Hironori Yamamoto Yutaka Taketani Kyoko Morita Hiroomi Kanayama Susumu Kagawa Eiji Takeda 《International journal of urology》1996,3(Z1):s92-s94
To investigate whether rBAT gene products function as a crystine transporter component or as a transport activator, we microinjected several C–terminal deletion mutants of rBAT cRNA into Xenopus oocytes, and measured transport activity for arginine, leucine and cystine in the presence and absence of sodium. Wild type rBAT significantly stimulated the uptake of all 3 amino acids 10–20 fold compared to control mutants. On the other hand, no mutant, except a Δ511–685 mutant, stimulated the uptake of these amino acids. However, the Δ511–685 mutant significantly increased the uptake of arginine. In the presence of sodium, the Δ511–685 mutant also increased the uptake of leucine. The Δ511–685 mutant did not stimulate crystine uptake in the presence and absence of sodium. Furthermore, inhibition of L–arginine uptake by L–homoserine was seen only in the presence of sodium. These results suggest that mutant rBAT stimulates the endogenous amino acid transport system y+ in oocytes. Finally, rBAT gene products, as the primary cause of cystinuria, may function as activators of the amino acid transport system in renal brush border membrane. 相似文献
994.
Prenatal Etiologies of West Syndrome 总被引:7,自引:5,他引:2
Shunsuke Ohtahara Yoko Ohtsuka Yasuko Yamatogi Eiji Oka Harumi Yoshinaga Masahiro Sato 《Epilepsia》1993,34(4):716-722
Summary: We investigated the etiology of West syndrome (WS) with special reference to prenatal factors in 180 cases. Prenatal cause was the most frequent diagnosis (77 cases, 42.8%), followed by perinatal (25 cases, 13.9%) and postnatal factors (12 cases, 6.7%); 48 cases (26.7%) were of uncertain etiology; eighteen cases (10.0%) were idiopathic. Of the three forms of age-dependent epileptic encephalopathy, prenatal cause was present in 12 of 15 cases (80.0%) of early-infantile epileptic encephalopathy with suppression-burst, 77 of 180 cases (42.8%) of WS, and 31 of 123 cases (25.2%) of Lennox-Gastaut syndrome (LGS). Prenatal factors of WS included tuberous sclerosis (23), chromosome abnormalities (10), cerebral dysgen- esis (10), porencephaly (7), hydrocephalus (5), Aicardi syndrome (3), Aicardi syndrome associated with chromosome abnormality (1), and other causes (18). Chromosome abnormalities with WS consisted of 6 cases with 21 trisomy and one case each with 18q duplication, t(l;y) translocation, 7q duplication, and partial 2p trisomy. One patient with Aicardi syndrome also had a t(12;21) translocation. No significant difference was observed in the age of onset of WS among the five etiologic groups. The evolution from WS to LGS was not influenced by etiology, except for the idiopathic group. In patients followed for over 3 years, seizure remission occurred in 46.8% (22 of 47 cases) of the prenatal group. This was lower than the other four groups. Intellectual prognosis was also relatively poor in those with prenatal onset. Pyridoxal phosphate (PAL-P) treatment was effective in 9 of 70 (12.9%) prenatal cases and 5 of 18 (27.8%) idiopathic cases. Notably, efficacy rates of 14.3, 14.8%, and 20.0% were observed in those with tuberous sclerosis, brain malformation, and chromosome abnormality, respectively. No significant difference in the effect of synthetic ACTH (Cortrosyn-Z) was observed among the five groups. These findings suggested that WS due to prenatal etiologies and those due to other etiologies are essentially homogeneous in age of onset and clinicoelectrical features, although each has some individual characteristics. We conjecture that WS is one form of an age-specific epileptic reaction to diverse nonspecific exogenous insults. 相似文献
995.
Masaharu Takigawa D.D.S. & Ph. D. Eiji Shirai Motomi Enomoto Yuji Hiraki Fujio Suzuki Tsuyoshi Shiio Yasumi Yugari 《Journal of bone and mineral metabolism》1988,6(2):29-38
Cartilage-derived anti-tumor factor (CATF) inhibits the proliferation and DNA synthesis of bovine pulmonary artery endothelial
(BPAE) cells in culture (Takigawa, M.et al. Cell. Biol. Inn. Rep., 9, 619–625, 1985). In the present study, we partially purified CATF by monitoring inhibition of DNA
synthesis in BPAE cells and tested the effects of the purified materials on the growth of solid tumors and tumor-induced angiogenesis.
Crude CATF (CATF20–300k), the fraction of 20 k to 300 k daltons, separated by ultrafiltration was further separated into three fractions by ultrafiltration.
The fraction of 100 k to 300 k daltons (CATF100–300k) caused slightly more inhibition than CATF20–300k of DNA synthesis in BPAE cells. On the other hand, the fraction of 20 k to 50 k daltons had only a slight effect, and the
fraction of 50 k to 100 k had even less effect on DNA synthesis in BPAE cells. CATF100–300k caused slightly more inhibition than CATF20–300k of the growth of solid tumors of B16 melanoma, while the fraction of 20 k to 100 k daltons did not inhibit the growth of
tumors at all. CATF100–300k also inhibited B16 melanoma-induced angiogenesis in chick embryo chorioallantoic membranes (CAM), whereas the fraction of
20 k to 100 k daltons had little effect on the angiogenesis. CATF100–300k was further purified by DEAE-Sepharose CL-6B chromatography. The main peak with activity on DNA synthesis in BPAE cells was
eluted with 0.3 to 0.35 M NaCl at pH 8.0. The activity of this peak on DNA synthesis in BPAE cells was about 70 fold that
of CATF100–300k. The purified CATF also inhibited the growth of B16 melanoma and B16 melanoma-induced angiogenesis in CAM. On the other hand,
the inactive fraction on DNA synthesis in BPAE cells obtained by DEAE-Sepharose chromatography was also inactive in inhibiting
the growth of B16 melanoma and B16 melanoma-induced angiogenesis in CAM. These findings strongly suggest that CATF is an anionic
macromolecule(s) and has anti-angiogenic activity, thereby inhibiting the growth of solid tumors. 相似文献
996.
Tamura T Fukase Y Goke E Yamada Y Sato S Nishiyama M Ito K 《Journal of periodontal research》2005,40(3):269-276
OBJECTIVE: This study evaluated new bone regeneration beyond the skeletal envelope within an occlusive titanium cap on rabbit calvaria using microfocus computed tomography images. METHODS: In 10 rabbits, the calvaria was exposed and a circular groove was prepared. After penetrating the marrow, a standard hemispherical titanium cap was placed in the groove and covered with a cutaneous flap. After 1 or 3 months, the animals were killed and the calvariae and titanium caps were dissected. After taking microfocus computed tomography images of the specimens, histological sections were made. The specimens were observed using three-dimensional images constructed from the microfocus computed tomography images, and the histological sections were examined to compute bone parameters. RESULTS: The three-dimensional images and histological specimens showed that new bone formed in flat, cup-like, and dome shapes. The bone parameters trabecular thickness and the proportion of marrow space to the capacity of the titanium cap increased, whereas bone density decreased, and there were significant differences between the 1- and 3-month groups. DISCUSSION: First, a cylinder of new bone formed from the existing bone. Gradually, bone formed along the cap wall and the new tissue formed in a crater indented centrally. Finally, the new tissue formed in the shape of a dome. CONCLUSION: Trabecular bone formed along the wall of the titanium cap, and bone filled the inside of the cap within 3 months. 相似文献
997.
998.
Yamada E Kusaka T Miyamoto K Tanaka S Morita S Tanaka S Tsuji S Mori S Norimatsu H Itoh S 《Clinical physiology and functional imaging》2005,25(4):203-208
The purpose of this study was to investigate the effects of whole body vibration (WBV) on oxygenation of vastus lateralis muscle during squatting exercise. Eighteen male subjects [mean age, 27.3 +/- 6.0 (SD) years; mean height, 171.8 +/- 4.9 cm; mean weight, 64.4 +/- 6.1 kg] performed squatting exercise on a vibration platform for 3 min with and without vibration, and changes in oxygenation of the vastus lateralis muscle were determined by near-infrared spectroscopy. The muscle oxygenation levels and total haemoglobin and myoglobin levels (total Hb/Mb) decreased during squatting exercise with and without vibration. After exercise, the muscle oxygenation level and total Hb/Mb rapidly increased from the minimum value during exercise and remained constant for latter 10 min. The muscle oxygenation levels with vibration from 90 to 180 s after the start of squatting exercise were significantly lower than those without vibration. Total Hb/Mb with vibration from 90 s after the squatting exercise to 540 s were significantly higher than those without vibration. This study demonstrated that WBV exercise affects the oxygenation level of vastus lateralis muscle and reduces muscle oxygenation level compared to that with no WBV. Therefore, WBV exercise may be an efficient training stimulus for muscle deoxygenation. 相似文献
999.
Satomi M Shimizu M Shinya E Watari E Owaki A Hidaka C Ichikawa M Takeshita T Takahashi H 《The Journal of infectious diseases》2005,191(2):174-181
Recent findings suggest that macrophage-tropic human immunodeficiency virus type 1 (HIV-1) produced in colostrum/early breast milk may hold a clue to determine the mechanisms of transmission of HIV-1 via breast-feeding. Here, we show that the majority of CD4(+) cells in the colostrum are CD14(+) macrophages expressing both chemokine receptors and DC-SIGN, a dendritic cell-specific receptor for HIV-1. The R5-type macrophage-tropic HIV-1 isolate NL(AD8) infected such breast-milk macrophages and caused them to secrete virus particles efficiently; however, the secreted virions showed only a weak transmissibility to their susceptible target, MAGIC-5 cells. When stimulated with interleukin-4, the breast-milk macrophages demonstrated a striking enhancement of expression of DC-SIGN and showed a strong capacity to transmit NL(AD8) virions to MAGIC-5 cells, which was specifically blocked by anti-DC-SIGN-specific antibody. These results suggest that HIV-1 virions captured by DC-SIGN, but not secreted cell-free virions, may be more efficiently transmitted to other compartments, such as the gastrointestinal tract, through acidic gastric juice. 相似文献
1000.
Some herbal medicines, including Aconiti tuber (Aconitum carmichaeli Debeaux, Ranunculaceae), have been recognized as being effective for the treatment of a "peripheral uncomfortable feeling of cold (hie)". We hypothesized that these compounds affect peripheral vascular function via the nitric oxide (NO) system, which leads to recovery from "hie". To answer this question, we investigated Aconiti tuber-induced changes in plasma levels of nitrite (p-NO2-) and nitrate (p-NO3-), final nitric oxide-oxidation products measurable in vivo. After written informed consent was obtained, patients suffering from "hie" were treated with several kinds of kampo (Japanese traditional herbal medicine), selected on the basis of traditional theory. Twenty-four patients took kampo formulas, some included Aconiti tuber (n=11; A-group) and others did not (n=13; C-group), for 4 weeks. p-NO2- and p-NO3- levels were measured before the start and after 4 weeks of treatment. In the A-group, the p-NO2- plus p-NO3- (p-NOx) level was significantly increased at 4 weeks (p=0.04), while that of the C-group was not. There was a statistically significant increase in the p-NOx level of the A-group as compared to the C-group (d.f.=1,22, F=9.38, p=0.006). The results suggest that Aconiti tuber may increase NO production in humans. 相似文献