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21.
Naomi Seki Jun Mitsui Masataka Hoshino Masahiro Akishiro Yoshikazu Ugawa Jun Goto Shoji Tsuji 《Brain and nerve》2006,58(1):68-73
A 51-year-old male who showed severe ataxia, dysarthria, bilateral blepharoptosis, diplopia and nystagmus with the subacute onset was reported. The chest roentgenogram and CT scan revealed mass lesions at the hilus of the left lung. The tumor markers, NSE and ProGRP, were elevated; 12.8 ng/ml (< or = 10) and 140.7 pg/ml (< or = 46), respectively. The biopsy was performed surgically and the small cell carcinoma of the lung was confirmed pathologically. His cerebellar symptoms were considered to be caused by the paraneoplastc cerebellar degeneration. However, the blepharoptosis was peculiar. The electrophysiological studies were carried out The muscle strength test of the right APB muscle was 5. But the supramaximum stimulation of the right median nerve evoked only 2.0 mV of CMAP of the right APB muscle. The repetitive stimulation tests of the same nerve showed that 3 Hz stimulation resulted in 42% waning but 20 Hz stimulation evoked no waxing. The post-exercise test of the right APB muscle showed 73% increase of the CMAP. These findings indicated that he also suffered from Lambert-Eaton myasthenic syndrome. The titer of the antibody against the P/Q type voltage-gated calcium channel (VGCC) was remarkably elevated, 1,920 pM. None of the following antibodies were detected ; they included antibodies against acetylcholine receptor, Hu, Yo, Ri, Ma-2, CRMP-5, amphiphysin and glutamic acid dehydrogenase. The small cell carcinoma was treated with the combination of irinotecan hydrochloride and cisplatin, leading to the reduction of the mass lesions and the tumor markers. His cerebellar symptoms improved slightly but his blepharoptosis was unchanged. The titer of antibody against the P/Q type VGCC reduced remarkably to 451.8 pM. We reviewed reported cases associated with paraneoplastic cerebellar degeneration and Lambert-Eaton myasthenic syndrome and discussed the relation between the paraneoplastic syndromes and autoantibodies. 相似文献
22.
Resolution of homonymous visual field loss documented with functional magnetic resonance and diffusion tensor imaging. 总被引:5,自引:0,他引:5
Masaki Yoshida Masahiro Ida Thien Huong Nguyen Marie-Therese Iba-Zizen Luc Bellinger Jean Louis Stievenart Takehiko Nagao Shinsuke Kikuchi Takaaki Hara Takuya Shiba Kenji Kitahara Emmanuel Alain Cabanis 《Journal of neuro-ophthalmology》2006,26(1):11-17
A 68-year-old man developed right homonymous hemianopic paracentral scotomas from acute infarction of the left extrastriate area. He was studied over the ensuing 12 months with visual fields, conventional MRI, functional MRI (fMRI), and diffusion tensor imaging (DTI). As the visual field defect became smaller, fMRI demonstrated progressively larger areas of cortical activation. DTI initially showed that the lesioned posterior optic radiations were completely interrupted. This interruption lessened in time and had disappeared by one year after onset. fMRI and DTI are innovative measures to follow functional and structural recovery in the central nervous system. This is the first reported application of these imaging techniques to acute cerebral visual field disorders. 相似文献
23.
M A Shibata M Kagawa M Kawabe A Hagiwara S Fukushima 《Teratogenesis, carcinogenesis, and mutagenesis》1991,11(6):305-316
Promoting effects of Na or K phosphate salts on rat two-stage bladder carcinogenesis were compared. Animals were treated with 0.05% N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) in their drinking water for 4 weeks and thereafter received 1.4% Na3PO4, 2.0% NaH2PO4, 1.0% K3PO4, or 2.5% KH2PO4, these dietary concentrations being selected because they result in approximately equal levels of Na+ and K+ in the urine, equivalent to moderate natriuresis or kaluresis in comparison with our previous data. Treatment with Na3PO4 or K3PO4 induced significant increase in urinary pH compared with control values, whereas urinary pH in the NaH2PO4 and KH2PO4 groups was comparable to control values. With regard to preneoplastic lesion development, both incidences and multiplicity were significantly increased in the groups given Na3PO4 or K3PO4 compared with both controls and NaH2PO4 or KH2PO4 groups, respectively. Furthermore, treatment with Na3PO4 significantly increased multiplicity of papillomas, accompanied by a tendency to increased incidence. No statistically significant difference in promoting potential between Na3PO4 and K3PO4 groups was evident. The present results thus suggest that tumor promotion under conditions of moderate natriuresis or kaluresis depends primarily on high urinary pH. 相似文献
24.
Shigeji Matsumoto Mizuho Ikeda Toshimi Nishikawa Shinki Yoshida Takeshi Tanimoto Masahiro Ito Chikako Saiki Mamoru Takeda 《The Journal of pharmacology and experimental therapeutics》2002,300(2):597-604
The excitatory responses of deflationary slowly adapting pulmonary stretch receptor (SAR) activity to lung deflation ranging from approximately -15 to -25 cm of H(2)O for approximately 5 s were examined before and after administration of flecainide, a Na(+) channel blocker, and K(+) channel blockers, such as 4-aminopyridine (4-AP) and tetraethylammonium (TEA). The experiments were performed in anesthetized, artificially ventilated rats after unilateral vagotomy. The deflationary SARs increased their activity during lung deflation and its effect became more pronounced by increasing the degree of negative pressure. During lung deflation the average values for the deflationary SAR adaptation index (AI) were below 40%. Intravenous administration of veratridine (50 microg/kg), an Na(+) channel opener, stimulated deflationary SAR activity: one maintained excitatory activity mainly during deflation and the other receptors showed a tonic discharge during both deflation and inflation. Despite the difference in deflationary SAR firing patterns after veratridine administration, flecainide treatment (6.0 mg/kg) blocked veratridine-induced deflationary SAR stimulation and also caused strong inhibition of the excitatory responses of deflationary SARs to lung deflation. Under these conditions, the average values for deflationary SAR AI were over 90%. The responses of deflationary SARs and deflationary SAR AI to lung deflation were not significantly altered by pretreatment with either 4-AP (0.7 and 2.0 mg/kg) or TEA (2.0 and 6.0 mg/kg). These results suggest that the excitatory effect of lung deflation on deflationary SAR activity is mediated by the activation of flecainide-sensitive Na(+) channels on the nerve terminals of deflationary SARs. 相似文献
25.
K Funaishi K Kawamura F Satoh M Hiramatsu M Hagiwara M Okanish 《The Journal of antibiotics》1990,43(8):938-947
Antibiotics 6108 A1, B, C and D, a new series of analogues of rosaramicin, were found together with rosaramicin, juvenimicin A4 and M-4365 A1 from the cultured broth of strain BA06108 which was assigned to be a new species of Micromonospora. 6108 A1 and C showed inhibitory activity against Gram-positive and some Gram-negative bacteria as potent as rosaramicin and exhibited low acute toxicity in mice. However, 6108 B showed less potent antimicrobial activity and 6108 D showed higher toxicity than those two antibiotics. 相似文献
26.
Intracytoplasmic lumina (ICL) in human oviduct epithelium were investigated with transmission electron microscopy. ICL were found in 43 out of 60 cases examined. They were ultra-structurally characterized by microvilli lining the lumina, periodic acid-thiocarbohydrazide-silver proteinate (PA-TCH-SP) staining-positive finely granular material in the lumina, and secretory vesicles in the cytoplasm surrounding the lumina. Although ICL were observed at various heights within the epithelium, they were mainly seen in basally located cells that did not face the oviduct lumen. Various stages of formation and development of ICL were observed in the basally located epithelial cells with secretory activities. Primary ICL were originated in the cytoplasm where the secretory granules were aggregated with smooth-surfaced tubular vesicles. Electron microscopic observations after PA-TCH-SP staining revealed that ICL were formed by fusion of the secretory granules with the tubular vesicles. ICL were enlarged into round profiles by further fusion of secretory granules and tubular vesicles, and subsequently opened to the oviduct lumen, or fused to each other to develop into large extracellular cysts within the epithelium. 相似文献
27.
β2-glycoprotein-I (β2GPI) is a phospholipid-binding plasma protein that consists of five homologous domains. Domain V is distinguished from others by bearing a positively charged lysine cluster and hydrophobic extra C-terminal loop. β2GPI has been known as a natural anticoagulant regulator. β2GPI exerts anticoagulant activity by inhibition of phospholipid-dependent coagulation reactions such as prothrombinase, tenase, and factor XII activation. It also binds factor XI and inhibits its activation. On the other hand, β2GPI inhibits anticoagulant activity of activated protein C. According to the data from knockout mice, β2GPI may contribute to thrombin generation in vivo. Phospholipid-bound β2GPI is one of the major target antigens for antiphospholipid antibodies present in patients with antiphospholipid syndrome (APS). Binding of pathogenic anti-β2GPI antibodies increases the affinity of β2GPI to the cell surface and disrupts the coagulation/fibrinolysis balance on the cell surface. These pathogenic antibodies activate endothelial cells via signal transduction events in the presence of β2GPI. Impaired fibrinolysis has been reported in patients with APS. Using a newly developed chromogenic assay, we demonstrated lower activity of intrinsic fibrinolysis in euglobulin fractions from APS patients. Addition of monoclonal anti-β2GPI antibodies with β2GPI also decreased fibrinolytic activity in this assay system. β2GPI is proteolytically cleaved by plasmin in domain V (nicked β2GPI) and becomes unable to bind to phospholipids, reducing antigenicity against antiphospholipid antibodies. This cleavage occurs in patients with increased fibrinolysis turnover. Nicked β2GPI binds to plasminogen and suppresses plasmin generation in the presence of fibrin, plasminogen, and tissue plasminogen activator (tPA). Thus, nicked β2GPI plays a role in the extrinsic fibrinolysis via a negative feedback pathway loop. 相似文献
28.
Takashi Ishimori Satoru Nakano Masahiro Kagawa Koiku Yokoe Tarou Togami Hirofumi Asakura Toshiaki Kusuhara Motoomi Ohkawa Syeigo Nagao Yuichi Yamashita Satoshi Sugiura 《Magnetic resonance in medical sciences》2003,2(3):145-149
Three-dimensional fast asymmetric spin echo (3D FASE) cisternography provides high spatial resolution and excellent contrast as a water image acquisition technique. It is also useful for the evaluation of various anatomical regions. This study investigated the usefulness and limitations of virtual endoscopic images obtained by 3D FASE MR cisternography in the preoperative evaluation of patients with neurovascular compression. The study included 12 patients with neurovascular compression: 10 with hemifacial spasm and two with trigeminal neuralgia. The diagnosis was surgically confirmed in all patients. The virtual endoscopic images obtained were judged to be of acceptable quality for interpretation in all cases. The areas of compression identified in preoperative diagnosis with virtual endoscopic images showed good agreement with those observed from surgery, except in one case in which the common trunk of the anterior inferior cerebellar artery and posterior inferior cerebellar artery (AICA-PICA) bifurcated near the root exit zone of the facial nerve. The veins are displayed in some cases but not in others. The main advantage of generating virtual endoscopic images is that such images can be used for surgical simulation, allowing the neurosurgeon to perform surgical procedures with greater confidence. 相似文献
29.
30.
A human monoclonal antibody (MCA), CLN-IgG, showed cytotoxic effect in vitro against the cervical carcinoma cell line, ME-180, by antibody dependent cell-mediated cytotoxicity (ADCC). To determine which fractions of cells in peripheral blood lymphocyte (PBL) mediate ADCC, PBL were separated with nylon wool column and sheep red blood cells (SRBC). Both adherent cells (monocyte) and non-T, non-B cells showed cytotoxicity by ADCC. Human non-T, non-B cells showed higher cytotoxic activity against ME-180 cells than monocytes. Furthermore murine effector cells were less effective in ADCC than human effector cells with human MCA. 相似文献