[Acute hypertensive encephalopathy].
Explore the source record for details and available documents.
Acute Disease↗
Biomedical subjects
T Yoshimoto
Publications and source records attributed to T Yoshimoto.
[Interhemispheric asymmetry exists in female in the N100m source position of the auditory evoked magnetic fields].
The N100m source of the auditory evoked magnetic fields (AEFs) is located more posterior in the left than the right hemisphere in male subjects. However, whether this asymmetry exists in female subjects is controversial. The present study, analyzed the N100m source positions of the AEFs due to monaural tone stimuli using a helmet-shaped 66-channel magnetoencephalography system (CTF Systems) in 62 right-handed normal adults (24 females and 38 males). The best fit sphere was calculated for each subject from the head shape reconstructed from three-dimensional magnetic resonance images. N100m source positions were estimated using a double-dipole model. The contralateral N100m response to the stimulated ear was measured relative to the midpoint of the bilateral auricular points. Statistical analysis used a standardized head size for each subject based on the mean value of all subjects (r = 8.27 cm). In females, the N100m dipole positions were 0.00 +/- 1.02 cm anterior in the left hemisphere and 0.35 +/- 0.74 cm in the right (p < 0.02). In males, the N100m dipole positions were -0.31 +/- 0.81 cm (mean +/- standard deviation) anterior in the left hemisphere and 0.61 +/- 0.78 cm in the right (p < 0.0001). The interhemispheric difference in the N100m positions was 0.35 +/- 0.65 in females and 0.92 +/- 0.77 in males (p < 0.005). In conclusion, the left hemispheric N100m is located more posterior to the right in both genders. However, this functional asymmetry is more evident in males, like previous findings of more evident anatomical asymmetry in males.
Adult↗
[Neonatal intracranial tumor highly suspected of teratoma in the lateral ventricle consisting of multiple cysts: case report].
Neonatal intracranial teratoma is rare and early attempts at surgical treatment are not usually successful. We describe an exceptionally rare case of neonatal intracranial tumor in the lateral ventricle composed of multiple cysts with little mass content which was highly suspected of teratoma and treated successfully by microsurgery. A 55-day-old male was admitted to our hospital with complaints of convulsive seizure. Examination found no obvious neurological deficit except mild enlargement and bulging of anterior fontanel. There were no abnormal laboratory findings. Computerized tomography with contrast medium revealed an 8 cm multicystic lesion with little mass content in the right lateral ventricle and hydrocephalus. Magnetic resonance imaging showed the cystic content as slightly higher in intensity than CSF on the T1-weighted image and of higher intensity than CSF on the T2-weighted image. The cyst wall was enhanced on T1-weighted image with gadolinium. The aqueduct was obstructed by compression due to the intraventricular cyst. A right occipitoparietal craniotomy was performed, which disclosed a hair in the cyst wall, two huge cysts, and independence of the intracystic lesion from the lateral ventricle. The tumor was removed except for a small part adjacent to the pineal region, from which the tumor had presumably originated. Mature teratoma was highly suspected on the basis of the hair in the cyst wall and histological examination of the specimen, which revealed hamartomatous tissues derived from two germ cell layers. After surgery, his hydrocephalus was improved and convulsive seizures were reduced remarkably. He was discharged ten days later and is being followed up. Reoperation will be performed if regrowth of the residual tumor occurs.
Cerebral Ventricle Neoplasms↗
The future of aneurysm surgery.
Explore the source record for details and available documents.
Humans↗
[Diffusion-weighted MRI detectability of acute cerebral ischemia: comparison with eventual infarction].
To clarify the clinical significance of diffusion-weighted magnetic resonance imaging (DWI) hyperintensity in acute cerebral ischemia, 34 patients were investigated with cerebral ischemia that had lasted no more than 8 hours. Either a spin echo sequence with navigator echo (n = 21) or an echo planar sequence (n = 13) was used for DWI using 1.5 tesla magnet. The eventual infarction was judged from T2-weighted image (T2 WI) or CT performed 2-12 days after the onset and was classified into cortical (n = 24) or perforating artery (n = 10) area. The eventual infarction was compared in size with the acute DWI finding and expressed as larger, same or smaller. Thirty patients showed ischemic hyperintensity lesions on acute DWI (6 patients on T2 WI). In cortical artery areas, the eventual infarction was same as hyperintensity area of acute DWI in 15 cases, larger in 8 cases, smaller in 2 cases. In perforating artery areas, the eventual infarction was same as hyperintensity area of acute DWI in 8 cases, and larger in 2 cases. These results suggest that in the perforating artery areas, the acute DWI hyperintensity is a good predictor of the eventual infarction and that in cortical artery areas, dynamic ischemic process may continue for hours before resulting in the eventual infarction.
Acute Disease↗
[Rapid growth of glioblastoma during therapy for multiple myeloma: case report].
Rapid growth of a glioblastoma during therapy for multiple myeloma is reported. A 53-year-old man was admitted to our hospital with a right costal tumor, which was resected. The diagnosis was plasmocytoma. Urine protein electrophoresis showed a monoclonal peak in the region of gamma-globulin, and examination of the bone marrow revealed 17.8% of atypical plasma cells. Brain magnetic resonance (MR) imaging detected two small lesions, but these could not be identified as brain tumor. He received chemotherapy (melphalan 10 mg/day and predonin 30 mg/day for 4 days) and was discharged. Two weeks after discharge, he was readmitted because of left hemiparesis. T1-weighted MR imaging showed two large hypointense lesions in the right frontal lobe, with ring-like enhancement following Gd-DTPA infusion. 1H-MR spectroscopy showed typical findings of tumor with increased choline and lactic acid peaks. 201Tl SPECT revealed high accumulation in both early and delayed images. Right carotid angiography showed a hypervascular tumor with venous filling and mass effect. The lesions were resected via right frontal craniotomy, followed by intraoperative radiation and placement of an Ommaya reservoir. Histological examination showed the tumors were glioblastoma. The brain between the tumors also showed the typical appearance of glioblastoma, suggesting that the lesions were continuous. Postoperatively, the patient's left hemiparesis disappeared. He received local irradiation and chemotherapy and was then discharged. Coexistence of glioblastoma and multiple myeloma is rare. The cause may be genetic abnormality, but immunodeficiency due to multiple myeloma, surgical damage, or chemotherapy may have contributed to the rapid growth of the glioblastoma.
Antineoplastic Combined Chemotherapy Protocols↗
[Recent progress on the study of lipoxygenases--discovery of novel isozymes and molecular evolution].
Explore the source record for details and available documents.
Animals↗
Roles of heme oxygenase/carbon monoxide system in genetically hypertensive rats.
Although carbon monoxide (CO) has been suggested to be involved in the regulation of cardiovascular function through activation of soluble guanylyl cyclase, the pathophysiological significance in hypertension remains unknown. We therefore examined the effects of heme oxygenase (HO) inhibitor zinc protoporphyrin IX (ZnPP-IX) on blood pressure and determined HO mRNA expression level in various tissues in stroke-prone spontaneously hypertensive rats (SHR-SP/Izm) and Wistar Kyoto rats (WKY/Izm). Although ZnPP-IX significantly increased systolic blood pressure in both strains, the increment of blood pressure was larger in SHR-SP/Izm than in WKY/Izm. An essentially similar increase of blood pressure was demonstrated even in the ganglion blocker-pretreated rats. Constitutive type HO-2 mRNA levels in the aorta and kidney and inducible type HO-1 mRNA levels in the cardiac ventricle were significantly increased in SHR-SP/Izm compared with WKY/Izm. Clearly these results indicate the importance of the endogenous HO/CO system in the peripheral tissues in genetically hypertensive rats.
Animals↗
Auditory evoked magnetic fields in patients with right hemisphere language dominance.
Auditory evoked magnetic fields for pure-tone stimuli were measured in seven subjects with right hemisphere dominance for language using a whole-head magnetoencephalography system linked to magnetic resonance imaging. N100m responses were observed in both hemispheres in five subjects. The N100m response latency to contralateral stimulation was significantly shorter on the right than on the left in all cases. Normal right-handed subjects with left hemisphere dominance showed exactly the same responses. Therefore, the shorter N100m latency in the right hemisphere is independent of the dominant hemisphere for language.
Acoustic Stimulation↗
Nitric oxide mediates down regulation of lipoprotein lipase activity induced by tumor necrosis factor-alpha in brown adipocytes.
We previously reported that tumor necrosis factor-alpha (TNF-alpha)/cachectin suppresses lipoprotein lipase activity and its gene expression in brown adipocytes differentiated in culture. Recent evidence suggests that the effect of TNF-alpha over various cells is related to the enhanced production of nitric oxide (NO). The present study examined whether the suppressive effect of TNF-alpha on lipoprotein lipase activity is mediated by production of NO in the brown adipocytes. A reverse transcription-polymerase chain reaction (RT-PCR) assay revealed that TNF-alpha caused a concentration- and time-dependent expression of inducible NO synthase in brown adipocytes. Increasing concentrations of TNF-alpha (0.5-50 ng/ml) for 24 h resulted in a concentration-dependent decrease in lipoprotein lipase activity with reciprocal increase in nitrite production in the medium. The suppressive effect of TNF-alpha on lipoprotein lipase activity was significantly prevented by NO synthase inhibitors, NG-nitro-L-arginine methyl ester (L-NAME) and aminoguanidine, but not by D-NAME, an inactive isomer. Furthermore, 8-bromoguanosine 3',5'-cyclic monophosphate, cell permeant cGMP, suppressed lipoprotein lipase activity and 1 H-[1,2,4] oxadiazolo[4,3-a]quinoxalin-1-one, a selective inhibitor for soluble guanylate cyclase, restored the TNF-alpha-suppressed lipoprotein lipase activity. These results suggest that TNF-alpha stimulates brown adipocytes to express inducible NO synthase, followed by production of NO, which in turn mediates the suppressive effect of TNF-alpha on lipoprotein lipase activity. The effect of NO is mediated, at least partly, through production of cGMP.
Adipocytes↗
Diurnal change of arachidonate 12-lipoxygenase in rat pineal gland.
Rat pineal gland contains a 12-lipoxygenase as demonstrated by the enzyme activity, RNA blot analysis and in situ hybridization. Using rats maintained with 12-h dark and light cycles, dynamic changes of the enzyme in pineal gland were examined. When the crude extract of pineal glands was incubated with arachidonic acid and the reaction products were analyzed by reverse-phase HPLC, the glands obtained from rats in the dark showed a higher 12-lipoxygenase activity than those obtained from rats in the light. The pineal 12-lipoxygenase activity decreased after the light was on at 7 o'clock and reached the lowest level around 16 o'clock. Upon Western blot analysis the amount of 12-lipoxygenase protein in pineal glands was high in the dark and lowest around 16 o'clock. A half life of the enzyme protein was estimated to be approximately 2.8 h in organ culture of rat pineal glands. Northern blot analysis also revealed a higher 12-lipoxygenase mRNA level in pineal glands obtained in the dark than those obtained in the light. Thus, the 12-lipoxygenase of rat pineal glands shows a diurnal fluctuation that is regulated at the transcription level, and may play a certain role in the regulation of neuroendocrine processes of this gland.
Animals↗
Interrelation between nitric oxide synthase and heme oxygenase in rat endothelial cells.
The gene expression and interrelation of the constitutive type nitric oxide (NO) synthase-III as a NO-forming enzyme and heme oxygenase-2 as a carbon monoxide-forming enzyme were studied in cultured rat aortic endothelial cells. Both NO synthase-III and heme oxygenase-2 mRNAs were demonstrated in the endothelial cells by RNAase protection analysis. NO synthase-III mRNA was upregulated in the presence of the heme oxygenase inhibitor, zinc protoporphyrin IX, but not in the presence of the NO synthase inhibitor, N(G)-nitro-L-arginine. Although heme oxygenase-2 mRNA was significantly upregulated in the presence of both NO synthase inhibitor and heme oxygenase inhibitor, the increase was greater with the NO synthase inhibitor. These results provide the first evidence for the concomitant gene expression of NO synthase-III and heme oxygenase-2, and their compensatory interrelation in endothelial cells.
Animals↗
Propionibacterium acnes treatment diminishes CD4+ NK1.1+ T cells but induces type I T cells in the liver by induction of IL-12 and IL-18 production from Kupffer cells.
LPS injection into normal mice does not induce liver injury, while the same treatment of Propionibacterium acnes-primed mice induces severe liver injury, indicating that P. acnes treatment renders the mice susceptible to LPS. Since IFN-gamma sensitizes macrophages to LPS, we investigated the mechanism of induction and activation of IFN-gamma-producing (type 1) T cells by P. acnes. Twenty percent of liver lymphocytes of C57BL/6 mice are CD4+ NK1.1+ T cells that promptly produce IL-4 in response to anti-CD3 in vitro. However, P. acnes treatment diminished these lymphocytes. Therefore, liver lymphocytes from P. acnes-primed mice showed reduced IL-4 production. Furthermore, P. acnes treatment induced CD4- type 1 T cells in the liver. Isolated P. acnes-elicited Kupffer cells produced IL-12 and to a lesser degree IL-18 in vitro. Injection of anti-IL-12 Ab totally abrogated these actions of P. acnes, while injection of anti-IL-18 Ab caused only partial abrogation. Thus, administration of P. acnes diminished CD4+ NK1.1+ T cells, but induced type 1 T cells in the liver by induction of IL-12 and IL-18 production. Injection of IL-12 (approximately 1,000 ng) dose dependently diminished CD4+ NK1.1+ T cells, but induced type 1 T cells. In contrast, injection of IL-18 (approximately 1,000 ng) failed, although injection of a much larger dose of IL-18 (10,000 ng) or IL-18 (approximately 1,000 ng) with suboptimal doses of IL-12 (1-100 ng) diminished CD4+ NK1.1+ T cells in a dose-dependent manner. Thus, P. acnes treatment renders the mice highly susceptible to LPS by induction and activation of type 1 T cells.
Animals↗
Attenuation of nitric oxide synthase induction in IRF-1-deficient glial cells.
Nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) exerts inhibitory and cytotoxic effects on various cells including neuronal cells. Glial NO production, mediated via induction of iNOS, is thought to facilitate neuronal damage during cerebral ischemia. Recently, interferon regulatory factor-1 (IRF-1) has been reported to be an essential transcription factor for iNOS mRNA induction in murine macrophages. However, expression of IRF-1 and its role in the central nervous system have not been examined. In the present study, by using primary glial cell cultures from mice with targeted disruption of the IRF-1 gene, we investigated whether IRF-1 is involved in iNOS mRNA induction in glial cells. After stimulation with lipopolysaccharide and interferon-gamma, IRF-1 mRNA was strongly induced in wild-type (IRF-1 +/+) glial cells. iNOS mRNA induction and nitrite production in IRF-1 -/- glial cells were reduced as compared with those observed in IRF-1 +/+ glial cells. Diethyldithiocarbamate, a selective inhibitor of nuclear transcription factor kappa B (NF-kappa B), completely inhibited iNOS mRNA induction. These results suggest that not only NF-kappa B but also IRF-1 play important roles in iNOS mRNA induction in the central nervous system.
Animals↗
Nicotinamide inhibits inducible nitric oxide synthase mRNA in primary rat glial cells.
Nitric oxide (NO) exerts cytotoxic effects on various cells including neuronal cells. Glial NO production, mediated via induction of inducible NO synthase (iNOS), enhances neurotoxicity associated with the N-methyl-D-aspartate (NMDA) receptor. The present study examined whether nicotinamide, an inhibitor of poly (ADP-ribose) synthetase, inhibits NO formation in primary culture of rat glial cells. Nicotinamide (5-20 mM) suppressed iNOS mRNA expression and subsequent NO formation, which were induced by the combination of interferon-gamma and lipopolysaccharide, in a dose dependent manner. In addition, high-concentration (20 mM) nicotinamide decreased mRNA of interferon regulatory factor-1, a transcription factor which plays a major role in iNOS mRNA induction. These results suggest that nicotinamide may have protective effect on glial NO-related pathologies by preventing iNOS mRNA induction.
Animals↗
The origin of an EPR signal observed in dithiocarbamate-loaded tissues. Copper(II)-dithiocarbamate complexes account for the narrow hyperfine lines.
We examined the electron paramagnetic resonance spectra of some copper(II)-dithiocarbamate complexes in various media at liquid nitrogen temperature. It is demonstrated that Cu(II)-dithiocarbamate complexes exhibit atypical spectra with narrow hyperfine splitting, and that the dithocarbamates forming a water-insoluble Cu(II) complex are permeable in tissues, while those yielding water-soluble complexes are not.
Animals↗
Interleukin 18 together with interleukin 12 inhibits IgE production by induction of interferon-gamma production from activated B cells.
Interleukin 18 (IL-18), originally called interferon (IFN)-gamma-inducing factor, is a recently cloned cytokine of approximately 18 kDa synthesized by Kupffer cells and activated macrophages. The major activity associated with this molecule is the induction of IFN-gamma production from anti-CD3-activated T helper 1 cells in the presence of IL-12. B cells produce IgG1 and IgE when stimulated with anti-CD40 and IL-4. Here we show that a combination of IL-12 and IL-18 induces anti-CD40-activated B cells to produce IFN-gamma, which inhibits IL-4-dependent IgE and IgG1 production and enhances IgG2a production without inhibiting the B cell proliferative response. We also show that 24.3% of B cells became positive for cytoplasmic IFN-gamma after being stimulated with IL-12 and IL-18. Furthermore, we show that, like splenic T cells stimulated with anti-CD3, IL-12, and IL-18, B cells produced high level of IFN-gamma in response to anti-CD40, IL-12, and IL-18. Injection of a mixture of IL-12 and IL-18 into mice inoculated with Nippostrongylus brasiliensis or injected with anti-IgD induced IFN-gamma-producing cells that inhibit IgE production in them. Furthermore, B cells obtained from normal mice could develop into IFN-gamma-producing cells in IFN-gamma(-/-) host mice in response to in vivo treatment with IL-12 and IL-18. These results indicate that IFN-gamma from activated B cells differentially regulates IgG1/IgE and IgG2a responses in vitro and in vivo, indicating that B cells act as regulatory cells in the immune response. Present results suggested that injection of IL-12 and IL-18 could present a unique approach for the treatment of allergic disorders.
Animals↗
Changes in gene expression for skin-type fatty acid binding protein in hypoglossal motor neurons following nerve crush.
The changeability in the gene expression for five species of fatty acid binding protein (FABP) was investigated in the crushed hypoglossal nucleus by in situ hybridization histochemistry. Increased gene expression for skin-type fatty acid binding protein (S-FABP) was evident in the affected hypoglossal neurons on the 3rd day after nerve crush, and it lasted until the postoperative day 14. On the other hand, no significant gene expression for heart-, liver-, intestinal- or brain-type FABPs was detected in the hypoglossal neurons of normal control or in these neurons for 3 weeks after the nerve crush. These findings suggest that skin-type FABP may selectively contribute to some important roles in morphological and biochemical changes of neuronal cells associated with the nerve regeneration.
Animals↗