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Biomedical subjects

A Mochizuki

Publications and source records attributed to A Mochizuki.

At least 55 records · Page 3Linked to original sources

Amyloid load and neural elements in Alzheimer's disease and nondemented individuals with high amyloid plaque density.

The amyloid burden and relationship between amyloid deposits and neural elements were investigated in sections of prefrontal neocortex from eight Alzheimer's disease (AD) patients and four age-matched nondemented controls with high amyloid plaque density (HPND). Computer-based image analysis revealed that the total area occupied by betaA4 immunoreactivity was significantly greater (P < 0.031) in AD (27.1%) than in HPND (14.5%) sections. The total betaA4-positive area occupied by nondiffuse plaques was significantly greater (P < 0.05) in AD (13.6%) than in HPND (5.2%) sections. The percentage of diffuse (DPs) and nondiffuse plaques (NDPs) which contained neurons, astrocytes, microglia, dystrophic neurites, and amyloid precursor protein (APP) was also determined. The frequency of association between betaA4 and these neural elements was similar between AD and HPND cases in both diffuse and nondiffuse plaques. Forty percent of DPs in AD and HPND sections contained neuronal perikarya. Microglia, dystrophic neurites, and APP were detected in most nondiffuse plaques in both AD and HPND sections. While astrocyte cell bodies were not present in either diffuse or nondiffuse plaques, their processes were detected in most. These findings indicate that amyloid deposition and nondiffuse plaques are greater in AD than in HPND sections. The association between microglia and nondiffuse plaques supports the hypothesis that these resident immune cells participate in aggregation and redistribution of amyloid deposits and possibly formation of dystrophic neurites.

Age Factors↗

The evolution of genomic imprinting.

In some mammalian genes, the paternally and maternally derived alleles are expressed differently: this phenomenon is called genomic imprinting. Here we study the evolution of imprinting using multivariate quantitative genetic models to examine the feasibility of the genetic conflict hypothesis. This hypothesis explains the observed imprinting patterns as an evolutionary outcome of the conflict between the paternal and maternal alleles. We consider the expression of a zygotic gene, which codes for an embryonic growth factor affecting the amount of maternal resources obtained through the placenta. We assume that the gene produces the growth factor in two different amounts depending on its parental origin. We show that genomic imprinting evolves easily if females have some probability of multiple partners. This is in conflict with the observation that not all genes controlling placental development are imprinted and that imprinting in some genes is not conserved between mice and humans. We show however that deleterious mutations in the coding region of the gene create selection against imprinting.

Animals↗

Efficient promoter cassettes for enhanced expression of foreign genes in dicotyledonous and monocotyledonous plants.

A series of chimeric promoters for higher-level expression of foreign genes in plants was constructed as fusions of a gene for beta-glucuronidase (GUS) with the terminator of a gene for nopaline synthase (nos) or of the cauliflower mosaic virus (CaMV) 35S transcript, and the strength of these promoters was assayed in transient and stable expression systems in tobacco and rice. As parts of these promoters, the CaMV 35S core promoter, three different 5'-upstream sequences of the 35S promoter, the first intron of a gene for phaseolin, and a 5'-untranslated sequence (omega sequence) of tobacco mosaic virus were used in various combinations. In tobacco and rice protoplasts, all three fragments of the 35S promoter (-419 to -90, -390 to -90 and -290 to -90, relative to the site of initiation of transcription), the intron, and the omega sequence effectively enhanced GUS activity. Some chimeric promoters allowed levels of GUS activity that were 20- to 70-fold higher than those obtained with the 35S promoter in pBI221. In tobacco protoplasts, the two longer fragments of the 35S promoter were more effective than the shortest fragment. In rice cells, by contrast, the shortest fragment was as effective as the two longer ones. The terminator of the 35S transcript was more effective than that of the nos gene for gene expression. In transgenic tobacco plants, a representative powerful promoter, as compared to the 35S promoter, allowed 10- and 50-fold higher levels of expression on average and at most, respectively, with no clear qualitative differences in tissue- and organ-specific patterns of expression. When the representative promoter was introduced into tobacco with a gene for luciferase, the autofluorescence of detached leaves after a supply of luciferin to petioles was great and was easily detectable by the naked eye in a dark room.

Amino Acid Oxidoreductases↗

Sarcoidosis presenting as bilateral hydronephrosis.

We report an unusual case of sarcoidosis associated with bilateral hydronephrosis. The patient was a 53-year-old Japanese woman who presented with dysuria and urinary incontinence. Computed tomography of the abdomen showed bilateral hydronephrosis caused by a retroperitoneal mass, surrounded by enlarged retroperitoneal lymph nodes. Histological examination of the mass demonstrated noncaseating epithelioid cell granulomas involving the retroperitoneal lymph nodes. Corticosteroid therapy led to complete resolution of the retroperitoneal mass and hydronephrosis. This case emphasizes that sarcoidosis should be included in the differential diagnosis of a retroperitoneal mass.

Diagnosis, Differential↗

[A case of relapsing Guillain-Barré syndrome following Miller Fisher syndrome].

Miller Fisher syndrome (FS) is thought to be a variant of Gullain-Barré syndrome (GBS), both of which rarely relapse. We report a rare case of GBS that followed FS. A 38-year-old woman had ophthalmoplegia, ataxia and areflexia following an upper respiratory tract infection with a diagnosis of FS. Serum anti-GQ1b IgG antibody was found to be increased, but decreased through immunoadsorption as the neurological symptoms of the patient improved. She became completely asymptomatic three months after the onset of FS. Following a common cold two months later, however, she developed weakness of all four limbs and dysesthesia of hands and feet with albuminocytologic dissociation of cerebrospinal fluid, which was consistent with the diagnosis of GBS. Moreover, serum anti-GQ1b IgG antibody had increased again. Anti-GQ1b IgG antibody frequently becomes positive not only in FS but also GBS with ophthalmoplegia. However, the antibody was positive in this particular patient with GBS, even in the absence of ophthalmoplegia. This case suggests that anti-GQ1b IgG antibody might be a common pathogenesis of both FS and GBS.

Adult↗

[Pharmacological profiles of F-1322, a novel anti-asthmatic agent. (1). Mechanisms of action].

The pharmacological effects of N-[2-(4-(benzhydryloxy)piperidino)ethyl]-3-hydroxy-5-(3-pyridyl methoxy)-2- naphthamide (F-1322), a novel anti-asthmatic agent, was investigated in vitro. The results obtained were as follows: 1) In the isolated trachea of guinea pigs, F-1322 showed a markedly potent antagonistic action against the contraction induced by histamine, while it had little or no effect on 5-hydroxytryptamine-, acetylcholine-, leukotriene D4- or U-46619-induced contractions. 2) In rabbit platelets, F-1322 did not affect the platelet aggregation induced by platelet activating factor. 3) F-1322 significantly inhibited the thromboxane (TX) A2 synthetase (IC50 value: 1.7 x 10(-8) M) and 5-lipoxygenase (IC50 value: 9 x 10(-7) M) activities. 4) F-1322 had no effect on phospholipase A2, cyclooxygenase, Ca2+/calmodulin-dependent phosphodiesterase and phosphodiesterase activities. These in vitro studies suggest that the anti-asthmatic action of F-1322 is associated with histamine antagonism and an inhibitory action on TXA2 synthetase and 5-lipoxygenase activities.

Animals↗

[Surgical treatment of posterior mediastinal teratoma].

A 22-year-old male patient was admitted to our hospital because of an abnormal shadow on a chest X-ray taken for routine examination. Preoperative diagnostic work up including chest computed tomography and magnetic resonance imaging suggested that the tumor would most likely to be a posterior mediastinal lipoma. Through a right thoracotomy the tumor was removed successfully. Histologically it proved to be a mature teratoma. The incidence, etiology and diagnostic procedure of the mediastinal teratoma was discussed.

Adult↗

Characterization of platelet activity in neuroblastoma.

A study was conducted to characterize the platelet aggregation induced by neuroblastoma tissue to investigate the mechanism of hypercoagulability in patients with neuroblastoma. The patients whose tumor tissues were examined had been shown clinically to have enhanced platelet activity. Platelet aggregation induced by neuroblastoma tissue extract was compared with that of other pediatric tumors. The effects of pretreatment with an antithrombin agent and prostacyclin (PGI2) on the platelet aggregation induced by tumor tissue extracts were also evaluated. Tissue extracts of 12 of 15 neuroblastomas, 3 of 3 Wilms' tumors, and 1 pheochromocytoma were demonstrated to have an activity that potentiated platelet aggregation in vitro. The platelet aggregation induced by tissue extracts of neuroblastomas and other tumor tissues was suppressed almost completely by pretreatment with a PGI2 analogue. The aggregation induced by neuroblastomas and the pheochromocytoma was also suppressed by pretreatment with an antithrombin agent, argatroban, whereas the aggregation induced by Wilms' tumors was not suppressed by this agent. These results suggest that (1) malignant tumors in children also have some chemical substances that sensitize platelet activity, such as those in adult cancers, and (2) thrombin is one of the mediators stimulating platelet aggregation in cases of neuroblastoma, although it is unlikely to be a contributing factor in other pediatric malignancies such as Wilms' tumor.

Antithrombins↗

Susceptibility of a line of dolphin kidney cell culture to several herpesviruses.

A cell line was established from cell cultures of kidney cortex of a pantropical spotted dolphin, Stenella attenuate. The replication of 6 strains of herpesviruses was studied in the cells. Five strains of them, herpes simplex virus type I and type II, equine rhinopneumonitis virus, infectious bovine rhinotracheitis virus and Aujeszky's disease virus, were grown fairly well in showing clear cytopathic effects and plaques under agar overlay medium.

Animals↗

Argentophilic intracytoplasmic inclusions in multiple system atrophy.

Argentophilic intracytoplasmic glial inclusions were recently reported in olivo-ponto-cerebellar atrophy (OPCA). We examined the brains of 3 cases of OPCA [2 with striato-nigral degeneration (SND) and 1 without SND], 1 case of pure autonomic failure (PAF) without pathology of OPCA or SND, as well as 36 controls including 2 cases of Holmes' type cerebellar cortical atrophy and 2 cases of Joseph's disease. Although the inclusions were tubulin-positive, the immunoreactivity was different from that of the dendrites. Electron microscopically, the microtubular structures composing the inclusion were fuzzy with granular material. These findings may indicate that the microtubules composing the inclusions are modified. Inclusion-bearing cells appeared to be oligodendrocytes while many of them had larger and lighter nuclei than those of normal-looking oligodendrocytes without the inclusions. The inclusions were widely distributed in a characteristic fashion beyond the typical lesions of OPCA, SND and PAF. The distribution pattern was essentially the same in the case of PAF and 3 cases of OPCA irrespective of the presence or absence of OPCA or SND lesions. In contrast, argentophilic inclusions were not observed in other types of spinocerebellar degeneration, in Holmes' type cerebellar cortical atrophy or in Joseph's disease. It is suggested, in line with other studies, that the inclusion may be specific to OPCA and related disorders which include PAF and a useful marker to distinguish OPCA from other neurodegenerative diseases.

Adult↗

Hair growth on nude mice due to cyclosporin A.

One of the most common dermatological side effects of cyclosporin A (CsA) is dose-dependent hypertrichosis. Similar hair growth was noted in nude mice in an attempt to increase the acceptance of human xenografts with CsA in the T-cell-deficient congenitally athymic nude (nu/nu) mice. The aim of the present study was to further investigate the stimulation of hair growth on nude mice not only by oral administration of CsA but also by topical and subcutaneous administration of CsA. Young BALB/c female nude mice were treated for 3 or 4 weeks with topical, oral, or subcutaneous applications of CsA dissolved in olive oil at various doses. The hair of CsA-treated mice appeared to grow from 7 days after the treatment, even at low doses. Induced hair growth was dose-dependent and became clearly obvious 3 weeks after the treatment. The stimulation of hair growth was not restricted to the site of topical application. The distribution of the new hair depended on the natural pattern of hair growth in the mice. However, there was no hair growth in the control mice which were given only olive oil. Histological examination revealed that there were no differences in the structures of skin and hair between the control and the CsA-treated mice. Furthermore, the number of hair follicles did not remarkably increase after CsA treatment. The hair growth in the CsA-treated mice stopped after cessation of the treatment and returned to the level of the control mice on day 14 after the end of the treatment. Subsequent retreatment with CsA resulted in further regrowth of the hair.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗

[Sweet's syndrome with pregnancy].

A 31-year-old pregnant woman had eruptions on her wrist, face and neck. We diagnosed her as having Sweet's syndrome from clinical symptoms, histopathological and laboratory findings. We successfully treated her with prednisolone and there are no relapses after delivery. We studied her polymorphonuclear leukocyte activity by the polarization assay with N-formyl-methionyl-leucyl-phenylalanine as a chemoattractant and it is higher than that of control. It is known that Sweet's syndrome is accompanied with collagen diseases and malignant diseases or others as underlying diseases or conditions. Three cases of Sweet's syndrome associated with pregnancy have been reported before and this is the first one in Japan.

Adult↗

[A clinical study of the renal pelvis and ureteral cancer].

During the 13 years from 1976 to 1988, 160 patients with renal pelvic and ureteral cancer were reviewed based on a new general rule for clinical and pathological studies on renal pelvic and ureteral cancer of Japanese Urological Association. There were 71 renal pelvic cancers, 80 ureteral cancers, and 9 cancers in both regions. Patients ranged in age from 35 to 91 years old (average: 63). The involved side was right in 63 and left in 97. The most frequent symptom was hematuria, which was seen in 81.1%. IVP revealed the findings of filling defects, hydronephrosis, and non-visualized kidney in 99.7% of the patients. Total nephroureterectomy with bladder cuff resection was performed in 123 cases, nephroureterectomy in 16 cases, nephrectomy in 5 cases, partial ureterectomy in 10 case, and biopsy in 6 cases. As adjuvant therapies, irradiation was performed in 32 and chemotherapy in 123. Histologically, 156 were with transitional cell carcinoma, one squamous cell carcinoma, one adenocarcinoma and 2 unclear, the over-all survival rate of this study at 1, 3, 5 and 10 years were 86.8%, 73.0%, 65.3% and 45.6%, respectively. No patient with lymph-node metastasis (N+) survived longer than 5 years. All patients with M(1) died within one year. There were no difference of prognosis between renal pelvic cancer and ureteral cancer. Regarding various prognostic factors, our series gave the same results as previous reports. However, it should be stressed that pathological grading was the most important prognostic factor.

Adult↗

[A case of non-paralytic pontine exotropia due to pontine tegmentum lesion confirmed by magnetic resonance imaging and electronystagmography].

A case with non-paralytic pontine exotropia (NPPE) due to brainstem infarction is reported. A 77-year-old hypertensive man suddenly developed dizziness, double vision, dysarthria, and right ataxic hemiparesis. Oculomotor findings on admission consisted of: (1) full right exotropia in the primary position; (2) complete adductive paralysis of the left eye with slight preservation of convergence; (3) tonic deviation of the right eye to the full abducting position with right-beating nystagmus after an immediate forward gaze. The leftward saccades showed multiple saccades with slow velocity on electronystagmography (ENG). The right exotropia disappeared and the slight adductive paresis of the left eye remained with right monocular nystagmus seven weeks after the onset. Magnetic resonance imaging (MRI), which was performed nine weeks after the onset, disclosed a small lesion with high intensity involving the left medial longitudinal fasciculus (MLF) on T2-weighted spin echo image. The leftward saccades showed multiple saccades with normal velocity eleven weeks after the onset. The hypofunction of unilateral PPRF with ipsilateral MLF lesion probably causes the contralateral NPPE.

Aged↗

[Experimental chemotherapy using transplantable human oral cancer in nude mice by SRC assay].

I studied fundamentally 6-days subrenal capsule assay, using human oral cancer transplanted in nude mice. The relative variation of tumor size (delta TS/TSO) was calculated as follows; delta TS/TSO = (TS6-TSO)/TSO X 100(%), where TS 6 was the tumor size on day 6 and TSO that on day O, and more than a 10% decrease of delta TS/TSO in the treated group was considered as positive for chemosensitivity. The chemosensitive rates were 38.0 +/- 8.1% (mean +/- standard deviation) for control, -8.0 +/- 8.5% for 5-FU, 1.8 +/- 16.7 for PEP, 5.0 +/- 9.1% for CDDP, -26 +/- 9.6% for 5-FU + PEP and -17.0 +/- 6.7% for 5-FU + CDDP. A single chemotherapy was negative, but combination chemotherapy was positive and few side effects (body weight loss) was showed. The 6-days SRC assay (combined anticancer drugs) appeared to be useful for selecting sensitive drugs for oral cancer patient.

Animals↗