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The authors investigated the effect on the brain of red blood cells that had been modified by contrast media. Rat blood was mixed with an equivolume of contrast media, and up to 200 microL of the mixture was infused to the internal carotid artery of the rat. Evans blue was administered intravenously to assess the integrity of the blood-brain barrier (BBB). Immediately after the death of the animal, or 2.5 hours after the infusion, the brain was removed for evaluation of the degree of BBB destruction and edema. Extensive destruction of the BBB, cerebral edema, and death of the animals were induced by infusion of blood mixed with an ionic contrast medium, such as diatrizoate and iothalamate, which deformed red blood cells. Microscopic observation showed atrophy and necrosis of nerve cells and decomposition of nerve fibers in the affected area of the brain. Cerebral damage was not observed in rats injected with blood mixed with a nonionic contrast medium such as iopamidol, iopromide, or metrizamide, which had less effect on red blood cells. Cerebral damage also was observed in the rats injected with blood mixed with a hyperosmotic solution of mannitol, as well as washed red blood cells mixed with an ionic contrast medium. This study's results indicate that hyperosmotic ionic contrast media affect red blood cells and cause disturbance in cerebral circulation. 相似文献
3.
Tetsuo Nagatani Megumi Miyazawa Toshiko Matsuzaki Gaijiro Iemoto Shu-taku Kim Naoko Baba Kanata Miyakawa Hideaki Miyamoto Hiroshi Nakajima Yoshio Hirai 《The Journal of dermatology》1993,20(10):623-629
A 45-year-old man was referred to our department in March of 1989. Physical examination showed erythroderma, palmo-plantar hyperkeratosis, generalized lymphadenopathy, hepatosplenomegaly, and leukemic manifestation. The lymphocyte count in the peripheral blood before treatment was 1.7 × 104 cells/mm3. Atypical lymphocytes such as flower cells and lobulated cells were seen in the peripheral blood. A sample excised from a lymph node showed immunoblastic, pleomorphic T cells by a modified classification scheme of the Working Formulation. A high level of serum LDH was detected (2.1 times the upper normal limit). Anti HTLV-1 antibody was also detected in the serum. The atypical lymphocytes were positive for CD3, CD4, CD5, CD7 and HLA-DR, and negative for CD8. Thus, the clinical, pathologic and immunologic features were those of typical acute-type ATL. The patient was treated with VEPA-M for three months starting in March of 1989. Because of poor response, the patient was then treated with MACOP-B, M-FEPA, and VEPP-B for about one year from June of 1989 and has been free of disease up to the time of writing, March of 1993. 相似文献
4.
Spontaneous photon emission (chemiluminescence, CL) as a monitor of free radical evolution in Drosophila melanogaster which had been maintained at 25 or 30 degrees C for 5 days after emergence was measured. When maintained at 30 degrees C the fly CL intensity was stronger than at 25 degrees C. Under the condition of the higher temperature, the fly life span was shorter (mean life span = 29 days at 30 degrees C and 63 days at 25 degrees C), and oxygen consumption (3.7 microliters/mg.h at 25 degrees C, 4.9 microliters/mg.h at 30 degrees C) and the mobility (movement distance = 25 mm/min at 25 degrees C, 700 mm/min at 30 degrees C) increased, together with augmentation of phospholipid hydroperoxide in the fly total lipids. The CL spontaneously emitted from fly homogenate was decreased by the free radical scavengers both in experiments in vivo and in vitro. The hypothesis is proposed that as the oxygen metabolism grows active, the chemiluminescent reactions that involve oxygen-dependent free radical metabolism, including membrane phospholipid hydroperoxidation, contribute to the acceleration of senescence of fly bodies. 相似文献
5.
Yoshitaka Hirooka Yoshikuni Kimura Masatsugu Nozoe Yoji Sagara Koji Ito Kenji Sunagawa 《Hypertension research》2006,29(1):49-56
Amlodipine is a dihydropyridine calcium channel blocker that is widely used for the treatment of hypertensive patients and has an antioxidant effect on vessels in vitro. The aim of the present study was to examine whether treatment with amlodipine reduced oxidative stress in the brains of stroke-prone spontaneously hypertensive rats (SHRSP). The animals received amlodipine, nicardipine or hydralazine for 30 days in their drinking water. Levels of thiobarbituric acid-reactive substances (TBARS) in the brain (cortex, cerebellum, hypothalamus, and brainstem) were measured before and after each treatment. Systolic blood pressure decreased to similar levels in the amlodipine-, nicardipine-, and hydralazine-treated groups. Urinary norepinephrine excretion was significantly reduced in SHRSP after treatment with amlodipine, but not with nicardipine or hydralazine. Levels of TBARS in the cortex, cerebellum, hypothalamus, and brainstem were significantly higher in SHRSP than in Wistar-Kyoto rats (WKY), and were reduced in amlodipine-treated, but not in nicardipine- or hydralazine-treated, SHRSP. Electron spin resonance spectroscopy revealed increased levels of reactive oxygen species in the brains of SHRSP, which were reduced by treatment with amlodipine. Intracisternal infusion of amlodipine also reduced systolic blood pressure, urinary norepinephrine excretion, and the levels of TBARS in the brain. These results suggested that oxidative stress in the brain was enhanced in SHRSP compared with WKY rats. In addition, antihypertensive treatment with amlodipine reduced oxidative stress in all areas of the brain examined and decreased blood pressure without a reflex increase in sympathetic nerve activity in SHRSP. 相似文献
6.
The ultrasonograms of ulcerative colitis (UC) in active stage show hypoechoic changes of the colorectal wall from the mucosal layer to the deeper layers. These endoscopic ultrasound (EUS) changes of the wall recognized in active stage disappear or normalize in the stage of remission. When the stage of UC is exacerbated, the hypoechoic changes of the wall extend from the mucosal layer to the deeper layers with the increase of wall thickness. These EUS images of active UC are classified into the following types: UC‐M, thickening of the whole wall with the structure preserved; UC‐SM, hypoechoic changes reach the superficial portion of third layer with the thickening of whole wall; UC‐SM deep, hypoechoic changes reach the deeper portion of third layer with the thickening of whole wall; UC‐MP, hypoechoic changes reach the fourth layer with the thickening of whole wall; UC‐SS/SE, hypoechoic changes penetrate through the fourth layer with the thickening of whole wall. With the help of EUS we can demonstrate the severity of inflammation in UC. Moreover, in severe cases of UC, the treatment strategy including emergency surgery can be determined. EUS is a valuable method in the management of UC. 相似文献
7.
Tetsumori Yamashima Takaomi C. Saido Masatoshi Takita Atsuo Miyazawa Jun Yamano Atsuo Miyakawa Hisashi Nishijyo Junkoh Yamashita Seiichi Kawashima Taketoshi Ono Tohru Yoshioka 《The European journal of neuroscience》1996,8(9):1932-1944
To clarify the mechanism of postischaemic delayed cornu Ammonis (CA)-1 neuronal death, we studied correlations among calpain activation and its subcellular localization, the immunoreactivity of phosphatidylinositol 4,5-bisphosphate (PIP2) and Ca2+ mobilization in the monkey hippocampus by two independent experimental approaches: in vivo transient brain ischaemia and in vitro hypoxia-hypoglycaemia of hippocampal acute slices. The CA-1 sector undergoing 20 min of ischaemia in vivo showed microscopically a small number of neuronal deaths on day 1 and almost global neuronal loss on day 5 after ischaemia. Immediately after ischaemia, CA-1 neurons ultrastructurally showed vacuolation and/or disruption of the lysosomes. Western blotting using antibodies against inactivated or activated μ-calpain demonstrated μ-calpain activation specifically in the CA-1 sector immediately after ischaemia. This finding was confirmed in the perikarya of CA-1 neurons by immunohistochemistry. CA-1 neurons on day 1 showed sustained activation of μ-calpain, and increased immunostaining for inactivated and activated forms of μ- and m-calpains and for PIP2. Activated μ-calpain and PIP2 were found to be localized at the vacuolated lysosomal membrane or endoplasmic reticulum and mitochondrial membrane respectively, by immunoelectron microscopy. Calcium imaging data using hippocampal acute slices showed that hypoxia-hypoglycaemia in vitro provoked intense Ca2+ mobilization with increased PIP2 immunostaining specifically in CA-1 neurons. These data suggest that transient brain ischaemia increases intracellular Ca2+ and PIP2 breakdown, which will activate calpain proteolytic activity. Therefore, we suggest that activated calpain at the lysosomal membrane, with the possible release of biodegrading enzyme, will cause postischaemic CA-1 neuronal death. 相似文献
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9.
N Shinoura T Kondo I Muraoka Y Tsukamoto M Yoshioka H Miyazawa 《No shinkei geka. Neurological surgery》1990,18(6):557-561
Two cases of sacrococcygeal teratoma in female infants are reported. Case 1. A newborn baby with a hemispheric mass on her hip underwent surgery 3 days after birth and the lesion proved to be an immature teratoma. The serum AFP level was very high but became normal one month after the operation. The child also had agenesis of the corpus callosum and arachnoid cysts in right middle fossa. She died after developing shunt infection. Case 2. A newborn baby with a mature teratoma was operated on the day following birth. The tumor was subtotally removed, and there has been no recurrence after 6 months. Sacrococcygeal teratoma in female infants is often associated with agenesis of the corpus callosum and arachnoid cysts. They tend to develop almost at the same time as the teratoma. It is often difficult to determine whether the infant should be treated by chemotherapy or not if the teratoma is immature, especially when it has been totally removed, the serum AFP is normal, and the tumor is pathologically of a low grade. 相似文献
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