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21.
Shuichi Umeoka Koichi Baba Kiyohito Terada Kazumi Matsuda Takayasu Tottori Naotaka Usui Keiko Usui Fumihiro Nakamura Yushi Inoue Tateki Fujiwara Tadahiro Mihara 《Epileptic Disord》2007,9(4):443-448
We report a patient manifesting seizures with bilateral symmetric tonic posturing, which were markedly reduced after resection of the left precuneus. A 16-year-old man had sudden onset, complex partial seizures with bilateral symmetric tonic posturing since the age of eight years. Magnetic resonance fluid-attenuated inversion-recovery imaging revealed a hyperintense lesion in left precuneus. In almost all focal seizures recorded during an invasive EEG evaluation, ictal onset was detected from the inferomesial aspect of the lesion, but fast paroxysmal discharges from the ipsilateral supplementary motor area (SMA) were observed just before the clinical onset. After surgical excision of the EEG onset zone, including the lesion, seizure frequency was markedly (> 95%) reduced. By the 20th month after surgery, there were only brief nocturnal seizures involving slight elevation of both shoulders and slight abduction of both arms, with preservation of consciousness occurring once every few days. Invasive EEG findings and surgical outcome suggested that the epileptic activity originating from the epileptogenic zone may have propagated to the symptomatogenic zone including mainly the ipsilateral SMA. In summary, we report an interesting case of bilateral symmetric tonic posturing suggesting propagation to the SMA. MRI and invasive EEG confirmed the epileptogenic focus as a precuneate cortical dysplasia lesion.[Published with video sequences]. 相似文献
22.
Antimetastatic Activity of Polymeric RGDT Peptides Conjugated with Poly(ethylene glycol) 总被引:1,自引:0,他引:1
Ikuo Saiki Junya Yoneda Yu Igarashi Miho Aoki Naoto Kusunose Kei-ichi Ono Ichiro Azuma 《Cancer science》1993,84(5):558-565
Polymeric peptides containing defined repetitive or cyclic structures of RGDT sequence, (RGDT)n (n = 1 to 11) and cyclo(RGDT)n (n=2 to 4), at a dose of 500 μg exhibited an inhibitory effect on experimental lung metastasis upon co-injection with tumor cells and the magnitude of the effect increased in parallel with the increase of degree of repetition of the RGDT sequence. The conjugation of (RGDT)n (n = 1, 5, 11) with poly(ethylene glycol), PEG as a polymeric carrier led to enhanced inhibition of lung metastasis in proportion to the degree of RGDT sequence repetition and in a dose-dependent manner. Multiple i.v. administrations of PEG-(RGDT)11, at 2-day and 3-day intervals before the excision of primary tumors, effectively inhibited spontaneous lung metastasis by s.c. inoculation of tumors, whereas (RGDT)11 exhibited inhibition of lung metastasis only when given at 2-day intervals. This indicates that the conjugation of PEG with (RGDT)n allowed the prolongation of administration interval, implying a sustained inhibitory effect on tumor metastasis. In support of this supposition, a decrease in the arrest of radiolabeled tumor cells in the lungs was observed when PEG-(RGDT)11 was co-injected i.v. with tumor cells, or injected i.v. one day before tumor inoculation. In contrast, (RGDT)11 significantly inhibited the tumor cell arrest in the lungs only upon co-injection with tumor cells. We also noted that (RGDT)n, cyclo(RGDT)n and PEG-(RGDT)11 inhibited tumor cell invasion into Matrigel in a concentration-dependent manner and in proportion to the degree of RGDT sequence repetition, indicating that the peptide-mediated antimetastatic effect is partly associated with the anti-invasive potential. Thus, the conjugation of anti-cell adhesive and antimetastatic RGDT peptide with PEG might provide a therapeutically promising basis for the prevention of cancer metastasis (“anti adhesion therapy”). 相似文献
23.
24.
Y Terada H Suma T Saito S Fukuda T Takayama Y Wanibuchi S Furuta 《Kyobu geka. The Japanese journal of thoracic surgery》1990,43(11):873-877
The long term (10 to 15 years) results of coronary artery bypass grafting (CABG) were studied in 20 patients. The duration of follow-up was ranged from 130 to 170 months with mean 146.4 months. Ten out of 20 patients underwent coronary angiography (CAG), which disclosed that the late patency of saphenous vein (SV) grafts was 68.8% (11/16), but 54.5% (6/11) of patent SV grafts showed atherosclerotic changes such as irregularity and localized narrowing. On the other hand, internal thoracic artery (ITA) grafts were all patent without any atherosclerotic luminal changes. We recognized that ITA grafts were superior to SV grafts from an angiographic standpoint of view in the long term in Japan. 相似文献
25.
Tohru Murakami Takao Hijikata Miho Matsukawa Harunori Ishikawa Hiroshi Yorifuji 《Developmental dynamics》2006,235(2):506-514
Here, we present the first report of the molecular cloning of zebrafish protocadherin 10 (Pcdh10, OL-protocadherin) and describe its functional analyses in the development of segmental plate. Epitope-tagged Pcdh10 expressed in embryos was localized on cell peripheries of adjacent cells. In situ hybridization showed that pcdh10 was expressed in the paraxial mesoderm (PAM) and developing somites, and in the pineal body, the diencephalon, and the vicinity of otocysts. Expression in PAM increased in the last few presumptive somites, reached the maximum level in the latest segmenting somites, and decreased thereafter during somite maturation. These expression patterns suggested that Pcdh10 is involved in development of PAM and somites. This was confirmed by morpholino knockdown and dominant-negative inhibition of Pcdh10 in embryos, which disturbed movements of PAM cells and somite segmentation. Comparative studies showed that pcdh10 expression lasted up to approximately three times longer in maturing somites than that of paraxial protocadherin (pcdh8). They also indicated that the adaxial cells expressed pcdh8 but not pcdh10. We propose that Pcdh10 is involved in the morphogenic movements of PAM cells and somite segmentation and that differential adhesion of Pcdh8 and Pcdh10 plays a role in the morphogenic machinery of somites and adaxial cells. 相似文献
26.
H. Maeda M. Sato A. Yoshikawa M. Kimura T. Sonomura M. Terada K. Kishi 《Neuroradiology》1997,39(8):546-550
In patients with hepatic cirrhosis, the globus pallidus and putamen show high intensity on T1-weighted MRI. While the causes
of this high signal have been thought to include paramagnetic substances, especially manganese, no evidence for this has been
presented. Autopsy in four cases of hepatic cirrhosis permitted measurement of metal concentrations in brain and histopathological
examination. In three cases the globus pallidus showed high intensity on T1-weighted images. Mean manganese concentrations
in globus pallidus, putamen and frontal white matter were 3.03 ± 0.38, 2.12 ± 0.37, and 1.38 ± 0.24 (μg/g wet weight), respectively,
being approximately four- to almost ten-fold the normal values. Copper concentrations in globus pallidus and putamen were
also high, 50 % more than normal. Calcium, iron, zinc and magnesium concentrations were all normal. The fourth case showed
no abnormal intensity in the basal ganglia and brain metal concentrations were all normal. Histopathologically, cases with
showing high signal remarkable atrophy, necrosis, and deciduation of nerve cells and proliferation of glial cells and microglia
in globus pallidus. These findings were similar to those in chronic manganese poisoning. On T1-weighted images, copper deposition
shows no abnormal intensity. It is therefore inferred that deposition of highly concentrations of manganese may caused high
signal on T1-weighted images and nerve cell death in the globus pallidus.
Received: 12 August 1996 Accepted: 17 December 1996 相似文献
27.
Tetsuo Ohta Takukazu Nagakawa Hiroshi Itoh Luis Fonseca Itsuo Miyazaki Tadashi Terada 《Journal of gastrointestinal cancer》1993,14(3):283-289
Summary We present a serous cystadenoma of the pancreas with focal malignant changes, and describe its characteristic histological
features. On gross examination, a tumor was present on the anterior surface of the body of the pancreas and measured approx
25×25⋻20, mm. Microscopically, most tumor cells showed the typical histological features of serous cystadenoma, characterized
by a microcystic architecture and glycogenrich cells with a uniform and bland appearance. However, in some areas, a tendency
to papillary structures with fibrovascular cores was noted. These papillary lesions were composed mainly of nonmucinous, glycogen-poor
epithelial cells, the nuclei of which showed a mild atypia. In addition, vascular and perivascular invasion was focally observed.
However, there was no clinical evidence of local or distant metastasis. From these findings, we diagnosed this lesion as a
serous cystadenoma of the pancreas with focal malignant changes rather than a serous cystadenocarcinoma of the pancreas. 相似文献
28.
Although investigators have demonstrated that neocartilage can be constituted in a predetermined shape and in complex three-dimensional structures, such as a human ear, by using cell transplantation on polymer constructs, many unsolved problems still remain. The crucial issues for auricular tissue engineering consisted of optimal cell culture environment, choice of polymers, behavior of chondrocytes, study of cell-polymer constructs in an acceptable animal model, and long-term structural integrity. Here we describe our tissue engineering approaches for auricular reconstruction including auricular scaffold fabrication, in vitro chondrogenesis, in vivo immunocompromized xenograft and immunocompetent autologous animal models, and long-term follow-up. Though many current obstacles regarding auricular tissue engineering still exist, we demonstrate techniques of auricular scaffold fabrication with promising in vitro and in vivo neocartilage formation, optimal selection and application of animal models, and, to the best of our knowledge, the first report of different biodegradable biomaterial trials and the longest in vivo results (10 months) for auricular tissue engineering. 相似文献
29.
E-cadherin gene mutations in human intrahepatic cholangiocarcinoma 总被引:11,自引:0,他引:11
Deletions or mutations of the E-cadherin gene may result in reduced cell adhesiveness. In particular, conservative point mutations within the N-terminal calcium-binding pocket (including exons 7, 8, and 9) are frequently detected in several cancers and are enough to abolish cell-cell adhesion. There have been no studies on E-cadherin gene mutations in human intrahepatic cholangiocarcinoma (ICC). Human ICCs were therefore investigated for E-cadherin gene mutations within exons 7, 8, and 9. In addition, the relationships were analysed between their mutations and the immunohistochemical expression of E-cadherin, histological grade, and clinicopathological parameters. The E-cadherin gene was analysed in 34 tumours by nested polymerase chain reaction/single-strand conformation polymorphism (PCR/SSCP) followed by DNA sequencing. In four of the 34 cases (11.8%), tumour-restricted mobility shifts were observed; two cases harboured a single shift, one case presented two different mobility shifts, and one case presented three different mobility shifts within exons 7 and 8, encoding extracellular domains of E-cadherin. Polymorphism as previously reported was not identified and all seven new DNA alterations were not present in genomic DNA of non-tumour origin. The E-cadherin gene mutations correlated significantly with down-regulated E-cadherin protein expression and high ICC histological grade. These data suggest that E-cadherin gene mutations in ICC are associated with reduced cell adhesiveness and high histological grade. 相似文献
30.
The structure of the avian fast skeletal muscle troponin T gene: seven novel tandem-arranged exons in the exon x region 总被引:1,自引:0,他引:1
Miyazaki J Jozaki M Nakatani N Watanabe T Saba R Nakada K Hirabayashi T Yonemura I 《Journal of muscle research and cell motility》1999,20(7):655-660
To elucidate the mechanism that produces enormous molecular diversity in troponin T (TnT) of fast skeletal muscle, we determined the 5-half genomic sequence of the chicken fast muscle TnT gene. The sequence of ca. 16 kb included seven exons (exons 1, 2, 3, 4, w, 5, and 6), which have been reported previously and presumed by sequencing TnT cDNAs. Additionally we found six 15 nt and one 18 nt sequences in the region between exons 5 and 6 (i.e. the exon x region). They were encompassed by consensus splice donor and acceptor sites and preceded by putative branch sites, and designated herein as exons xa to xg. Our result shows that the sequence derived from exons x1, x2, and x3, the exons presumed previously by cDNA sequencing, is actually encoded by the seven exons xa to xg, establishing the precise gene structure in the exon x region. Based on our data, together with that on the 3-half genomic sequence of the quail fast muscle TnT gene, we conclude that the avian fast skeletal muscle TnT gene includes 27 exons, 16 of which are alternatively spliced. 相似文献