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Biomedical subjects

M Fukui

Publications and source records attributed to M Fukui.

At least 235 records · Page 13Linked to original sources

Effects of treatment with angiotensin-converting enzyme inhibitor (ACEI) or angiotensin II receptor antagonist (AIIRA) on renal function and glomerular injury in subtotal nephrectomized rats.

The aim of this study was to determine if treatment with angiotensin-converting enzyme inhibitors (ACEI) or angiotensin II receptor antagonists (AIIRA) might decrease urinary albumin excretion and prevent glomerular enlargement and glomerulosclerosis in subtotal (5/6) nephrectomized rats. Morphometric image analysis of glomeruli was also performed in the subtotal nephrectomized rats. The nephrectomized rats were treated with ACEI (enalapril 100 mg/l), AIIRA (L-158,809 10 mg/l) or TRX (reserpine 5 mg/ l, hydralazine 80 mg/l, and hydrochlorothiazide 25 mg/l) and euthanized at 16 weeks after renal ablation. Treatments were started at 2 weeks (early treatment: Group I) or 8 weeks (later treatment: Group II) after the ablation. ACEI and AIIRA treatments were equally and significantly effective in limiting albuminuria and progression of glomerular sclerosis. TRX was also as effective in decreasing urinary albumin excretion and preserving the renal function as ACEI or AIIRA in Group I. The improvement of albuminuria, glomerular enlargement and sclerosis after these treatments in Group II was significantly less than that in Group I. It appears that the early treatment with angiotensin converting enzyme inhibitor, angiotensin II receptor antagonist or reserpine, hydralazine and hydrochlorothiazide (TRX) may prevent glomerular injury in human patients with renal hypertension.

Albuminuria↗

Effects of benidipine hydrochloride on antioxidant enzyme activity in stroke-prone spontaneous hypertensive rats (SHR-SP).

Effects of benidipine hydrochloride or triple therapy (hydralazine, reserpine, and hydrochlorothiazide) on renal cortical and medullary intrinsic antioxidant enzyme (AOE) activity were evaluated in stroke-prone spontaneously hypertensive rats (SHR-SP) as an animal model for human essential hypertension with cerebral stroke. This study showed a significant decrease of renal intrinsic glutathione peroxidase (GSH-Px) activity in untreated SHR-SP. Renal GSH-Px activity in untreated SHR-SP was significantly lower than that in Wister Kyoto rats (WKY) as a normotensive reference strain. GSH-Px activity in SHR-SP was significantly improved after benidipine hydrochloride therapy. Levels of urinary albumin excretion or creatinine clearance (Ccr) in SHR-SP were also improved after the therapy. Glomerular sclerosis index was slightly improved in SHR-SP treated with benidipine hydrochloride according to light microscopic analysis. It appears that hypertension may influence the renal intrinsic GSH-Px activity, albuminuria, and Ccr in SHR-SP. Thus it is indicated that control of blood pressure may improve the GSH-Px activity in SHR-SP.

Animals↗

Diagnostic significance of antibodies to glutamic acid decarboxylase in Japanese diabetic patients with secondary oral hypoglycemic agents failure.

Some non-insulin-dependent diabetes mellitus (NIDDM) patients are positive for antibodies to glutamic acid decarboxylase (anti-GAD), and they tend to develop insulin deficiency. The aim of this study was to evaluate the prevalence of anti-GAD in NIDDM with secondary failure of sulfonylurea agents (NIDDM-SF) and to investigate the diagnostic significance of seropositivity for anti-GAD in NIDDM-SF patients by evaluating human leukocyte antigen (HLA)-DRB1 alleles concurrently. The prevalence of anti-GAD in NIDDM-SF, NIDDM, and new-onset (within 1 year after onset) insulin-dependent diabetes mellitus (IDDM) was 9.3% (39/420), 3.1% (12/392), and 65.0% (13/20), respectively. Pancreatic beta cell function deteriorated in NIDDM-SF patients positive for anti-GAD. HLA-DRB1 allele typing revealed that NIDDM-SF patients positive for anti-GAD were significantly associated with DRB1*0901 (RR = 2.81, P < 0.01), which is one of the susceptible alleles to IDDM. Shorter interval before development of secondary failure and insulin deficiency were significantly associated with the presence of DRB1*0901 (P < 0.05) in NIDDM-SF patients positive for anti-GAD. In conclusion, nearly 10% of NIDDM-SF patients are positive for anti-GAD, suggesting that an autoimmune mechanism might play an important role in the pathogenesis of NIDDM-SF patients. In addition, a combination of serological marker (anti-GAD) and genetic marker (HLA-DRB1) is useful for predicting clinical course of NIDDM patients with secondary failure of sulfonylurea agents.

Adolescent↗

A chronological evaluation of experimental brain infarct by diffusion-mapping and magnetization transfer contrast imaging.

BACKGROUND AND PURPOSE: There is a complex system of evolving physiochemical processes in the ischemic brain. The evaluation of this chain of processes is a major challenge of recent stroke studies. Two magnetic resonance imaging techniques: diffusion-weighted (DW) and magnetization transfer contrast (MTC) imaging were introduced in experimental studies and were shown to have sensitivity for different stages of brain infarct. MATERIALS AND METHODS: We used a reproducible middle cerebral artery (MCA) occlusion model in rat to examine infarcts of different time courses. Magnetic resonance T2-weighted (T2). DW, and MTC imaging were performed 3 h, 1 d, 3 d, 5 d, 2 w, 3 w, and 4 w after MCA occlusion. Haematoxylin/eosin (HE) stained sections, which revealed sub regions within infarct lesions, were compared to T2, DW, diffusion-mapping and MTC-mapping images. RESULTS: On DW images 3 hours post occlusion lesions were detected as an area with high signal intensity, while T2 imaging does not raise significant contrast of the lesion at this early stage. Three sub regions of the lesion having different ADCs, are discernible on diffusion-mapping images from 1 day to 7 days. The decrease of MTC effect was measured within the infarct lesion from core to marginal zone, from 7 days to 4 weeks. CONCLUSIONS: Diffusion-mapping imaging may help to examine brain infarction from 3 hours to 5 days. MTC imaging recognizes infarcts 7 days after the onset. Following this stage, MTC-mapping images may provide a quantitative method to assess infarct size.

Animals↗

Apparent diffusion coefficient (ADC) and magnetization transfer contrast (MTC) mapping of experimental brain tumor.

Brain tumor tissue contains different pathological areas, such as tumor cell rich parts, necrotic tissues, and cyst. Furthermore, both neovascularization and edema formation progress along with the tumor progression. In this study we employed diffusion weighted (DW) and magnetization transfer contrast (MTC) imaging to chronologically investigate the biological characteristics of a rat glioma. RG-2 glioma cells were implanted stereotactically into the right hemisphere of male Wistar rats. MR images were taken 1, 2 and 3 weeks after inoculation. Apparent diffusion coefficient (ADC) and MTC values were calculated as follows; ADC = -ln (SI-DW/SI-T2)/1096, MTC = 1-SI-MTon/SI-MToff. Each mapping image was made based on the calculated average values of four pixels. The spatial signal changes and the real values were compared to the histological findings. The apparent increase of ADC was noted in the parenchyma adjacent to tumor suggesting the progression of edema. The tumor itself had similar or slightly increased ADC. Cystic and necrotic components appeared 2 weeks after implantation and they showed significantly higher ADC than those calculated in the contralateral putamen. On the other hand, MTC was slightly decreased in the parenchyma adjacent to the tumor, markedly within the tumor, and maximally in the cystic and necrotic area suggesting accumulation of macromolecules such as growth factors, cytokines, and serum albumin.

Animals↗

Medulloblastoma: survival and late recurrence after the Collins' risk period.

Sixty-three patients with cerebellar medulloblastoma were treated between 1963 and 1992 at our institution. Among them, 10 patients have survived beyond the Collins' risk period. These included 6 males and 4 females who ranged in age from 6 months to 12 years at the time of diagnosis. A total removal of the tumor was achieved in 4 patients, while there was a subtotal removal in 3, and a partial removal in 3. Histologically, 6 tumors were classified as a classical type of medulloblastoma, and 4 were diagnosed as being a desmoplastic type. Postoperatively, 9 patients received craniospinal radiation therapy, and one received local radiation to the primary site. During the follow-up period of 3.9-25.4 years, 5 patients have been in continuous remission for from 14.2 to 25.4 years and are leading normal lives, 2 have survived for 18.1 and 18.5 years with mild to moderate neurological deficits, while the remaining 3 died after the Collins' risk period. Two out of these last 3 patients were under the age of one year at the time of onset, while the remaining one died after a second recurrence. We conclude that careful follow-up is needed for all long-term survivors even after the Collins' risk period, especially for those who were under the age of 1 year at onset and who failed in the initial treatments.

Adolescent↗

Traumatic aneurysm of the superficial temporal artery in an elderly patient.

An elderly patient suffering from the posttraumatic development of a superficial temporal artery (STA) aneurysm is described. Because the patient had renal dysfunction, angiography was performed through a direct puncture of the anterior branch of the STA in order to reduce the required dosage of contrast medium. With the patient under local anesthesia, the STA was ligated proximal and distal to the aneurysm, and thereafter removed. The diagnosis and treatment of traumatic STA aneurysms in the elderly are discussed.

Aged↗

Micro-anatomical study of the carotid cave.

The surgical treatment of aneurysms located in the carotid cave is often hazardous and difficult. We studied the micro-anatomy of the carotid cave and its neighbourhood by microscopic observation and histological examination using 50 sides from 25 autopsy cases. The carotid caves were found in 34 out of the 50 sides (68%) examined and were usually located in the posteromedial aspect of the carotid dural ring. They were classified into three types according to the topographic micro-anatomy: the slit-type (17/50, 34%) which showed a small, thin recess of the dura mater with fine connective tissue loosely adhered to the carotid wall; the pocket-type (12/50, 24%) which had a definite dural pouch with the apex attached to the vessel wall; and the mesh-type (5/50, 10%) which formed a slit- or pocket-type dural cave covered with a mesh-like dural roof. The remaining 16 sides (32%) showed tight dural attachment without any caval structure around the dural ring. The posteromedial portion of the carotid dural ring had no contact with any bony structure, and this distinct anatomical feature thus appear to facilitate the formation of the carotid cave. Furthermore, the availability of this potential space and the closely situated origin of the superior hypophyseal artery as well as the haemodynamic effect of the internal carotid artery may allow the development of the carotid cave aneurysm.

Adult↗

Thalamic gliomas: a clinicopathologic analysis of 20 cases with reference to patient age.

Twenty patients (M 11, F9; ranging from 1-77 years old) with histologically proven glial tumours in the thalamic region, treated from 1979 until 1994 at Kyushu University Hospital were retrospectively reviewed and analysed in order to elucidate their clinical and neuropathological characteristics. The initial common clinical manifestations were those of increased intracranial pressure or motor weakness. The histological diagnosis of the tumour was pilocytic astrocytoma in 2 patients, fibrillary astrocytoma in 7, anaplastic astrocytoma in 7, and glioblastoma multiforme in 4. The initial treatment was surgery alone in 4 patients, surgery followed by radiation therapy in 5, surgery followed by radiation therapy and chemotherapy in 9, and conventional radiation therapy alone in 2 patients. The 3-year overall actuarial survival rate for all patients was 20% but was related to both the histological type and the age of the patients: As a result, the rate was 44% for patients with low-grade astrocytoma compared to 0% for those with high-grade astrocytoma. While 5 out of 11 patients under the age of 25 years at their initial presentation have survived for from 2-16 years after the diagnosis, all patients presenting after the age of 25 years died within 3 years after treatment. Thalamic glial tumours are not a homogeneous group of tumours in terms of clinical behaviour and histopathological features, and the poor overall results, especially in adult tumours, thus emphasise the need for continued research in the treatment of these tumours.

Adolescent↗

DNA typing of HLA in the patients with moyamoya disease.

Moyamoya disease is a clinical entity demonstrating a chronic occlusion of the cerebrovascular system. Although some possible etiological factors have been postulated, the etiology of this disease is still unknown. So far, some investigations have suggested the association between moyamoya disease and HLA in the serological typing. However, DNA typing of HLA have not been performed yet. Thus, we performed DNA-typing of HLA in the unrelated Japanese patients with definite moyamoya disease, using the polymerase chain reaction-sequence specific oligonucleotide probe (PCR-SSOP) technique. In the total patients, DQB1*0502 had a positive association with the disease. On the other hand, DRB1*0405 and DQB1*0401 showed a negative association. In comparing the early-onset and late-onset groups, two groups did not share the same disease associated alleles at all. Thus, the etiology of moyamoya disease seem to have a genetic background. Furthermore, different genetic factors might also be involved in the difference between the early-onset and late-onset groups.

Adult↗

Leser-Trélat sign with anaplastic ependymoma--an autopsy case.

A 36-year-old Japanese male, who 7 years previously had been diagnosed as having an ependymoma in the left parietal region, had received surgery, chemotherapy and radiotherapy. He later developed a rapid growth of multiple skin lesions on his back and extremities, which coincided with a regrowth of the tumor. Postmortem examination revealed that the ependymoma showed anaplastic transformation and necrosis; however, no malignancy was observed in the extracranial organs. The skin lesions were histologically diagnosed as seborrheic keratoses. We have, therefore, diagnosed the patient as having Leser-Trélat sign associated with anaplastic ependymoma.

Adult↗

Expression of neurofibromatosis 2 protein in human brain tumors: an immunohistochemical study.

The neurofibromatosis 2 (NF2) gene-encoded protein, named merlin, may function as a molecular linkage connecting cytoskeleton and plasma membrane. Merlin is thought to play a crucial role as a tumor suppressor not only in hereditary NF2-related tumors, but also in sporadic tumors such as schwannomas, meningiomas and gliomas. Using a merlin-expression vector system, we raised specific antiserum against merlin. We observed the intracellular distribution of merlin in cultured glioma cells, and further investigated merlin expression in 116 human brain tumors. Immunofluorescence microscopy revealed that merlin was localized beneath the cell membrane and concentrated at cell-to-cell adhesion sites, where actin filaments are densely associated with plasma membrane. By immunohistochemistry, none of the schwannomas from either NF2 patients or sporadic cases showed any immunoreactivity, while normal Schwann cells of cranial nerves were immunopositive. In meningiomas, merlin expression was frequently seen in the meningothelial subtype (8/10, 80%), but no expression could be detected in either the fibrous or the transitional variant. Most normal astrocytes were negative; however, reactive astrocytes often expressed merlin. Glioblastomas and anaplastic astrocytomas were found to be strongly positive, and focal positive staining was observed in fibrillary and pilocytic astrocytomas. Thus, the loss of merlin appears to be integral to schwannoma formation and the differential pathogenesis of meningioma subtypes. However, merlin alterations do not appear to play a critical role in either the tumorigenesis or malignant transformation of neoplastic astrocytes.

Brain Neoplasms↗

High prevalence of mitochondrial diabetes mellitus in Japanese patients with major risk factors.

To identify diabetes mellitus caused by the mitochondrial gene substitution at genomic nucleotide pair 3243 (M3243A-->G) we selected 87 diabetic patients with high risk factors such as maternal inheritance and hearing loss. Total DNA was extracted from peripheral leukocytes, and mitochondrial DNA fragments containing M3243A-->G were amplified by polymerase chain reaction (PCR). The amplified fragments were digested with a restriction endonuclease Apa1 and analyzed by agarose gel electrophoresis. The incidence of the M3243A-->G mutation was 4.6% (four of 87) in diabetic patients with maternal inheritance and/or hearing loss. In a subgroup with both maternal inheritance and hearing loss, the incidence of the mutation was as high as 21.4% (three of 14). Cardiac disorders were also present in all four diabetic patients with the mutation. This study suggests that maternal inheritance and hearing loss are useful clinical findings to identify diabetic patients with the mutation, and that cardiac involvement is a high risk factor for the M3243A-->G mutation.

Adult↗

Current state of study on moyamoya disease in Japan.

BACKGROUND: Moyamoya disease is a unique cerebrovascular disease with much higher incidence in Japanese and Asians than in Caucasians. The Research Committee on Spontaneous Occlusion of the Circle of Willis (Moyamoya disease) of the Ministry of Health and Welfare, Japan, has studied the pathogenesis, epidemiology, clinical investigations, and treatment of the disease since 1977. The current status of the study of moyamoya disease in Japan is presented. METHODS: There were 821 registered cases of moyamoya disease in Japan up to 1994. The study group also obtained statistical data from a questionnaire sent to hospitals dealing with the disease. [The data collected were analyzed.] RESULTS: The estimated number of patients in Japan through 1994 was 3800. Characteristic epidemiologic data were: female dominance (male to female ratio = 1:1.7); highest rate of onset in the age group below 10 years, with a second mild peak from 30-40 years; and rate of familial cases around 10%, including identical twins. The most recent development is diagnosis by MRI and MRA-it is now possible to obtain a diagnosis without conventional angiography. The study of the cerebral perfusion and metabolism by positron emission tomography (PET) or SPECT is becoming more important in understanding the state of illness and in deciding the indications for surgery. Treatment of moyamoya disease can be either medical or surgical. The latter consists of either direct bypass surgery (STA-MCA anastomosis) or indirect bypass procedures, including EDAS, EMS, EMAS, and omental transplantation. At present, although not statistically significant, the surgically-treated groups seem to have better results than the medically-treated groups. CONCLUSIONS: The clinical features of moyamoya disease are becoming more elucidated. However, further studies are necessary including the pathogenesis, which is still not known.

Age Distribution↗

A comparative study of embedded nerve tissue in six NF2-associated schwannomas and 17 nonassociated NF2 schwannomas.

BACKGROUND: Neurofibromatosis-2 (NF2) is an autosomal dominant disorder in which patients typically show bilateral acoustic tumors, and they are usually diagnosed histopathologically as schwannomas. The nerve of origin of a schwannoma is often demonstrated on the periphery along the capsule but not penetrating the substance of the tumor. However, there is a possibility that NF2 schwannomas and solitary schwannomas differ from participation in nerve components. METHODS: In this study, the authors noted the relationship between the tumor and the original nerves. To detect whether there were embedded nerves in the tumor, immunohistologic staining using neurofilament and myelin basic protein antibodies was performed on 6 NF2 schwannomas and 17 non-NF2 schwannomas. RESULTS: Four of five NF2 schwannomas had embedded nerves and one of four, which was considered to be the early stage of the tumor occurrence, remarkably embedded original nerves. On the other hand, embedded nerves were not seen in non-NF2 schwannomas. CONCLUSIONS: The authors concluded that the NF2 schwannomas tend have original nerves embedded in the tumor substance, which may be based on the difference of the motility of tumor cells, and the authors believe that it is difficult to remove NF2 schwannomas while preserving the original nerve.

Adolescent↗

Epidemiological features of moyamoya disease in Japan: findings from a nationwide survey.

To estimate an annual number of patients treated for Moyamoya disease in Japan and to describe the clinico-epidemiological features, a nationwide epidemiological survey was conducted in 1995. The study consisted of two questionnaires, which were distributed to departments randomly selected, of neurosurgery, neurology and pediatrics in hospitals throughout Japan. The first questionnaire inquired the number of the patients treated in 1994 and the second one detailed clinico-epidemiological information of each patient reported. Following major epidemiological findings emerged from the study: (a) The total annual number of patients treated for Moyamoya disease was estimated as 3900 (95% confidence interval (CI) 3500-4400) in Japan 1994, with the prevalence and incidence rates of 3.16 and 0.35 per 100,000 population, respectively; (b) the sex ratio (females to males) of the patients was 1.8; (c) the peak of age distribution of the patients was observed in 10-14 years old and a smaller peak in their forties; (d) the age at onset was under 10 years old in 47.8% of the patients, but some had developed the disease at the age of 25-49 years; (e) family history of Moyamoya disease was found in 10.0% of the patients; and (f) about 75% of the patients had normal activity of daily life or working ability even before treatment. The present findings were quite comparable with those obtained in the previous nationwide epidemiological survey in 1990.

Adolescent↗

Epidemiological survey of moyamoya disease in Korea.

To both clarify the current clinico-epidemiological features of Moyamoya disease in Korea as well as compare these cases with Japanese patients, 451 cases were collected from 26 Korean major neurosurgical institutes and 296 definite cases were analyzed statistically. Although the Korean age distribution patterns of Moyamoya disease showed two peaks, similar to Japanese patients, the Korean pattern was shifted to the right thus indicating Korean adult population to be 20% higher than that of Japanese patients. The female/male ratio was 1:3, which was slightly less than that for Japanese. The family occurrence rate in Koreans was 1.8%. The incidence of cerebral infarction and bleeding in Koreans was higher while transient ischemic attack (TIA) and seizure were less than that of Japanese. The incidence of infarction in children and of hemorrhage in children and adults were also statistically higher in Koreans. The incidence of hemorrhage was higher in females than in males. Both the age at onset and sex affected the disease type. Single encephalo-duro-arterio-synangiosis (EDAS) was performed on 87.6% of all surgical cases. Although the incidence of bleeding was higher in Korea, the outcomes of the patients were similar to that of the Japanese patients. Although Korean Moyamoya disease showed a relatively higher incidence of hemorrhage and adult onset, the overall clinical background was similar to that of Japanese patients.

Adolescent↗