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1.
A 54-year-old female presented with subarachnoid hemorrhage due to rupture of a small middle cerebral artery aneurysm, found to be thrombosed at surgery and not visualized on the preoperative angiograms. One major branch of the middle cerebral artery was found to be occluded near the trifurcation. The lumen of the branch proximal to the occlusion had appeared as the aneurysmal opacification on the preoperative angiograms.  相似文献   
2.
We report a case of aspergilloma in an 80-year-old male patient who had no identifiable underlying disease before surgery for pneumothorax. He was hospitalized for left pneumothorax. A chest CT revealed a large bulla in the left lung apex with a nodule (diameter; 1.5 cm) at the edge of the bulla. After thoracodocesis, air leakage persisted and a large bulla and nodule were resected. Aspergillus was detected histopathologically in the nodule. Treatment with itraconazole 200 mg a day followed, and 4 months later he had no recurrent pneumothorax or Aspergillus infection.  相似文献   
3.
Cerebral amyloid angiopathy (CAA) is an important cause of intracerebral hemorrhage and ischemic cerebrovascular disease in some normotensive elderly patients. The diagnosis is made by proof of amyloid deposition in the vessel wall. A case of recurrent and multiple intracerebral hemorrhages due to cerebral amyloid angiopathy after head injury is reported. A 74-year-old female was referred to our hospital because of head injury. CT scan showed traumatic subarachnoid hemorrhage and intraventricular hematoma. Her consciousness was clear but slight disorientation was recognized. Conservative therapy was performed. During the course subcortical hemorrhages occurred five times and during the second one, right frontal and right parietal hemorrhages occurred simultaneously. Her consciousness deteriorated. The second subcortical hemorrhage was especially complicated by a ventriculoperitoneal shunt operation. A biopsy of the cortex was performed and pathological examination revealed amyloid deposition in the walls of small pial and cortical vessels. Occasional duplicated wall, obliterative intimal proliferation and disappearance of elastic lamina were recognized. The patient sank into a vegetative state due to recurrent and multiple hemorrhages. CAA results in two possibilities, hemorrhage and ischemic cerebrovascular disease. When lobar or subcortical hemorrhage is encountered in a normotensive elderly patient, the possibility of a CAA-related hemorrhage should be considered. The author carefully emphasizes that there is indication for neurosurgical treatment in CAA patients and proposes that therapy for ischemic cerebrovascular disease should be given special attention.  相似文献   
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5.
The recent advent of neuroimaging techniques provides an opportunity to examine brain regions related to a specific memory process such as episodic memory encoding. There is, however, a possibility that areas active during an assumed episodic memory encoding task, compared with a control task, involve not only areas directly relevant to episodic memory encoding processes but also areas associated with other cognitive processes for on-line information. We used positron emission tomography (PET) to differentiate these two kinds of regions. Normal volunteers were engaged in deep (semantic) or shallow (phonological) processing of new or repeated words during PET. Results showed that deep processing, compared with shallow processing, resulted in significantly better recognition performance and that this effect was associated with activation of various brain areas. Further analyses revealed that there were regions directly relevant to episodic memory encoding in the anterior part of the parahippocampal gyrus, inferior frontal gyrus, supramarginal gyrus, anterior cingulate gyrus, and medial frontal lobe in the left hemisphere. Our results demonstrated that several regions, including the medial temporal lobe, play a role in episodic memory encoding.  相似文献   
6.
Previously, we demonstrated that human peripheral T lymphocytes revealed early apoptotic changes (annexin V-positive) and late apoptotic changes (propidium iodide-positive), at 13 and 24 h, respectively, after irradiation of 5 Gy. Changes in mitochondrial membrane potential were observed at 10 h after irradiation of 5 Gy. Subsequently, mitochondrial cytochrome c-release was confirmed. In order to elucidate the mechanism which acts prior to the mitochondrial membrane potential changes, we examined in the previous study the radiation dose and the timing of oxidative DNA damage induced in human peripheral T lymphocytes following 10 MV X-ray irradiation. As a result, the production of 8-oxoguanine, i.e., the product of oxidative DNA damage, was clearly identified starting at 10, 6, and 3 h, after 2, 5, and 20 Gy of irradiation, respectively. Therefore, we examined in the present study reactive oxygen species (ROS) formation in T lymphocytes following 5 Gy of irradiation. Using a CCD camera system, we monitored fluorescence in T lymphocytes loaded with the succinimidyl ester of dichlorodihydrofluorescein diacetate (H2DCFDA), which is non-fluorescent until oxidized by ROS. We found that ROS formation occurred immediately after irradiation, continued for several hours, and resulted in oxidative DNA damage. Therefore, the origin of hyper-radiosensitivity of T lymphocytes seemed to be the high production of ROS in the mitochondrial DNA following irradiation.  相似文献   
7.
The objectives of this study were to evaluate the correlations of the volumes of the gray matter and white matter with age, and the correlations of the tissue probabilities of the gray matter and white matter with age and several cerebrovascular risk factors. We obtained magnetic resonance (MR) images of the brain and clinical information from 769 normal Japanese subjects. We processed the MR images automatically by correcting for inter-individual differences in brain size and shape, and by segmenting the MR images into the gray matter and white matter. Volumetry of the brain revealed a significant negative correlation between the gray matter volume and age, which was not observed between white matter volume and age. Voxel-based morphometry showed that age, systolic blood pressure, and alcohol drinking correlated with the regional tissue probabilities of the gray matter and white matter.  相似文献   
8.
Spinocerebellar ataxia 27 (SCA27) is an autosomal dominant SCA caused by variants in the fibroblast growth factor 14 (FGF14) gene. We examined a Japanese SCA patient whose deceased father also suffered from SCA. The patient was a 63-year-old male. He graduated from junior high school but received no further education. The predominant complaint was slowly progressive dysarthria and gait disturbance, which appeared at age 47. He showed pathological saccadic dysmetria, saccadic intrusions into smooth pursuit eye movements, dysarthria, and limb and truncal ataxia. His gait was wide-based but he did not require a walking stick. Limb muscle strength was intact. Deep tendon reflexes were normal or slightly reduced. Pathological reflexes were absent. He demonstrated mildly impaired vibration sense in the lower limbs. There was no urinary dysfunction. Brain MRI showed cerebellar atrophy without brainstem involvement. We first confirmed the absence of repeat expansion in genes known to be responsible for SCAs 1–3, 6–8, 10, 12, 17, 36 and dentatorubral-pallidoluysian atrophy. By exome analysis, we identified a novel heterozygous variant (NM_004115, c.529A>T; Lys177X) in exon 4 of the FGF14 gene. This variant is expected to generate a truncated FGF14 protein lacking the heparin binding sites, those are likely to modify the activity of FGF14. We confirmed the absence of the variant in 502 healthy Japanese individuals by Sanger sequencing. There is no record of the variant in public databases. We conclude that the novel variation in FGF14 is causative for SCA27 in this patient.  相似文献   
9.
In our previous study, we examined reactive oxygen species (ROS) formation in T lymphocytes following 5 Gy irradiation. We found that ROS formation occurred immediately after irradiation, continued for several hours, and resulted in oxidative DNA damage. Therefore, the origin of the hyper-radiosensitivity of T lymphocytes seemed to be the high production of ROS in the mitochondrial DNA following irradiation. In the succeeding study, we examined radiation-induced ROS formation, oxidative DNA damage, early apoptotic changes, and mitochondrial membrane dysfunction in the human osteosarcoma cell line HS-Os-1. We found that ROS formation and oxidative DNA damage were actually scarcely seen after irradiation of up to 30 Gy in these cells, that mitochondrial membrane potential was preserved, and that apoptotic changes were not demonstrated despite the relatively high-dose irradiation of 30 Gy. In the present study, we examined the immunocytochemical characteristics of the apoptotic-resistance of the HS-Os-1 cell line against irradiation in order to clarify its possible implications regarding radiosensitivity. The results showed that these cells lack P53 and Bax protein expression, and strong peroxidase activity was confirmed in the nuclei of the cells. Moreover, SODII (manganese superoxide dismutase II) protein expression was gradually increased in spite of irradiation of up to 30 Gy. Therefore, it is concluded that HS-Os-1 cells are originally apoptotic-resistant and that the cells possess a strong ability to scavenge for free radicals. To convert these cells to a state of apoptotic-susceptibility, a powerful oxidant such as hydrogen peroxide might exert such an effect in terms of the production of hydroxyl radicals in lysosomes in the cells as shown in our previous studies. The origin of the radioresistance of the human osteosarcoma cell line HS-Os-1 is considered to to be low degree of ROS formation following irradiation, reflecting the strong scavenging ability of these cells for free radicals including hydroxyl radicals.  相似文献   
10.
Allosensitization represents a major barrier to heart transplantation (HTx). We assessed the efficacy and safety of complement inhibition at transplant in highly sensitized heart transplant recipients. We performed a single-center, single-arm, open-label trial (NCT02013037). Patients with panel reactive antibodies (PRA) ≥70% and pre–formed donor-specific antibodies (DSA) were eligible. In addition to standard of care, patients received nine infusions of eculizumab during the first 2 months posttransplant. The primary composite endpoint was antibody-mediated rejection (AMR) ≥pAMR2 and/or left ventricular dysfunction during the first year. Secondary endpoints included hemodynamic compromise, allograft rejection, and patient survival. Twenty patients were included. Median cPRA and mean fluorescence intensity of immunodominant DSA were 95% (90%–97%) and 6250 (5000–10 000), respectively. Retrospective B cell and T cell flow crossmatches were positive in 14 and 11 patients, respectively. The primary endpoint occurred in four patients (20%). Survival at 1 year was 90% with no deaths resulting from AMR. In a prespecified analysis comparing treated patients to matched control patients, we observed a dramatic reduction in the risk of biopsy-proven AMR in patients treated with eculizumab (HR = 0.36, 95% CI = 0.14–0.95, p = .032). Our findings support the prophylactic use of complement inhibition for heart transplantation at high immunological risk. ClinincalTrials.gov, NCT02013037.  相似文献   
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