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Biomedical subjects

H Mori

Publications and source records attributed to H Mori.

At least 307 records · Page 17Linked to original sources
PubMed1999

Contrasting role of presenilin-1 and presenilin-2 in neuronal differentiation in vitro.

Presenilin-1 (PS1) and presenilin-2 (PS2), the major genes of familial Alzheimer's disease, are homologous to sel-12, a Caenorhabditis elegans gene involved in cell fate decision during development. Recently, wild-type and mutant presenilins have been associated also with apoptotic cell death. By using stable transfection of antisense cDNAs, we studied the functions of PS1 and PS2 during neuronal differentiation in the NTera2 human teratocarcinoma (NT2) cell line. Expression of antisense PS1 resulted in a failure of the clones to differentiate into neurons after retinoic acid induction, whereas cells transfected with antisense PS2 differentiated normally. Concomitantly, antisense PS1 clones were associated with increased apoptosis both under basal conditions and during the early period of neuronal differentiation after retinoic acid treatment. Overexpression of bcl-2 in antisense PS1 clones reduced cell death and resulted in a recovery of neuronal differentiation. These studies suggest that PS1 plays a role in differentiation and cell death and that PS1 and PS2 have differing physiological roles in this experimental paradigm.

Alzheimer Disease↗
PubMed1999

Deposition of beta-amyloid subtypes 40 and 42 differentiates dementia with Lewy bodies from Alzheimer disease.

BACKGROUND: Alterations in the metabolism of the amyloid precursor protein and the formation of beta-amyloid (Abeta) plaques are associated with neuronal death in Alzheimer disease (AD). The plaque subtype Abeta(x-42) occurs as an early event, with Abeta(x-40) plaques forming at a later stage. In dementia with Lewy bodies (DLB), an increase in the amount of cortical Abeta occurs without severe cortical neuronal losses. OBJECTIVE: To advance our understanding of the natural history of Abeta in neurodegenerative diseases. DESIGN: We evaluated the expression of Abeta(x-40) and Abeta(x-42) in DLB using monoclonal antibodies and immunohistochemical techniques in 5 brain regions. The data were compared with those elicited with normal aging and from patients with AD. SETTING AND PATIENTS: A postmortem study involving 19 patients with DLB without concurrent neuritic degeneration, 10 patients with AD, and 17 aged persons without dementia for control subjects. RESULTS: The Abeta plaques were more numerous in patients with DLB than in controls in most brain regions, although the Abeta(x-42) plaque subtype was predominant in both conditions. Overall, Abeta(x-42) plaque density was similar in patients with DLB and those with AD, but Abeta(x-40) plaques were more numerous in persons with AD than in those with DLB. The ratio of Abeta(x-40) to Abeta(x-42) plaques was significantly reduced in persons with DLB compared with patients with AD. CONCLUSIONS: The Abeta plaques were more numerous in patients with DLB than persons with normal aging, but the plaque subtypes were similar. The relative proportion of the 2 Abeta plaque subtypes in DLB is distinguishable from that in AD.

Aged↗
PubMed1999

Histopathological features of liver damage induced by laser ablation in rabbits.

BACKGROUND AND OBJECTIVE: Possible mechanisms that promote or interfere with the effects of laser ablation of the liver have not been clarified. The aim of this study was to define the chronological alterations in the normal rabbit liver at early stages after laser ablation. STUDY DESIGN/MATERIALS AND METHODS: Rabbit livers were ablated with a laser via an optical fiber and then analyzed histopathologically by immunostaining for heat shock protein 70 (HSP70) and by the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) method. RESULTS: The lesions increased in size progressively over the 24 h that followed ablation and the area of the lesion coincided with the area that had been heated above 43 degrees C. TUNEL-positive hepatocytes were surrounded, at some distance, by HSP70-positive hepatocytes were surrounded, at some distance, by HSP70-positive hepatocytes at 6 h, and such cells were in contact with each other at 24 h. CONCLUSIONS: Injury to hepatocytes induced by laser ablation increases for 24 h and dying cells express nuclear HSP70, with subsequent fragmentation of DNA.

Animals↗
PubMed1999

Treatment of mandibular arteriovenous malformation by transvenous embolization: A case report.

BACKGROUND: Arteriovenous malformations (AVMs) of the mandible are relatively rare and potentially life-threatening lesions. Treatment is usually difficult. This study presents a case with high-flow AVM of the mandible in which most of the AVM were occluded by transvenous coil embolization. METHODS: Transvenous embolization using several size 57 microcoils and 3 Gianturco coils was performed through a right femoral vein access. The small residual AVM was occluded by superselective transarterial injection of cyanoacrylate. RESULTS: Angiography after embolization showed almost complete obliteration of AVM. Panoramic radiograph 2 years after treatment confirmed reossification. There was no recurrence of the symptoms in a follow-up evaluation 2 years later. CONCLUSION: Transvenous coil embolization may be a safer and more effective method in the treatment of mandibular AVM.

Adolescent↗
PubMed1999

Frequent mutations of the rat beta-catenin gene in colon cancers induced by methylazoxymethanol acetate plus 1-hydroxyanthraquinone.

Recent evidence suggests that the beta-catenin gene (CTNNB1) acts as an oncogene, and some human colon tumors with an intact APC gene have activating mutations in CTNNB1. In this study, mutations in the region corresponding to N-terminal phosphorylation sites (codons 1-51) of the rat Ctnnb1 gene were investigated in 20 colon tumors associated with ulcerative colitis and induced with methylazoxymethanol acetate and 1-hydroxyanthraquinone. Ninety percent (18 of 20) of the tumors induced in male F344 rats harbored mutations, which were detected in three of four adenomas (75%) and 15 of 16 adenocarcinomas (94%). Of 18 total missense mutations, 13 (72%) were G-->A transitions at position 101, three were G-->A transitions at position 94, and two were C-->T transitions at position 122, resulting in the amino acid substitutions Gly34-->Glu, Asp32-->Asn, and Thr41-->Ile, respectively. Although there were no mutations in the Apc gene, as we previously reported in the same tumor samples, the results obtained in this study strongly implicate the Apc-beta-catenin-T-cell factor (Tcf) signaling pathway in methylazoxymethanol acetate, 1-hydroxyanthraquinone-induced colon carcinogenesis.

Adenocarcinoma↗
PubMed1999

Primary leiomyosarcoma arising from the greater omentum in a 15-year-old girl.

We present here a case of primary leiomyosarcoma of the greater omentum in a 15-year-old girl. A laparotomy revealed a huge abdominal mass arising from the greater omentum. The tumor accompanied intra-abdominal dissemination, but had not invaded the muscle layer of the gastrointestinal tracts. An almost complete omentectomy and reduction of many disseminated tumors of abdominal wall and mesentery were performed for the case. The tumor was diagnosed as a leiomyoscarcoma by histological and immunohistochemical examinations. After the surgery, combination chemotherapy with cisplatin, ifosfamide, and pirarubicin was carried out. Leiomyosarcoma of the greater omentum in a young girl is extremely rare.

Adolescent↗
PubMed1999

Scintigraphic demonstration of renal cell carcinoma with I-131-6beta-iodomethyl-19-norcholesterol: a case report.

Extraadrenal abnormal uptake on adrenocortical scintigraphy has been reported rarely in the normal gallbladder, lipid cell tumor of the ovary, or in clear cell type renal cell carcinoma. Clear cell type renal cell carcinoma contains glycogen and cholesterol like the adrenal gland, but the uptake of the radionuclide I-131 cholesterol has been reported to be low and not sufficient to image it. Right renal and adrenal masses were incidentally discovered on abdominal CT scan in a patient with chronic renal failure resulting in bilateral acquired cystic kidney disease. Adrenocortical scintigraphy done to know the nature of the adrenal mass showed high uptake corresponding to the right renal mass and the right adrenal mass. Clear cell type renal cell carcinoma and adrenal adenoma with prominent clear cells were histologically confirmed on hematoxylin-eosin stain and in an immunohistochemical study with renal cell antibody. Not only low-density lipoprotein receptors mediated uptake but also overall replacement of the right non-tumorous renal parenchyma by acquired cysts may have played a role in imaging the renal cell carcinoma on adrenocortical scintigraphy.

19-Iodocholesterol↗
PubMed1999

Septic thrombosis of the portal vein due to peripancreatic ligamental abscess.

Septic thrombus formation of both the main portal vein and its intrahepatic branches were observed on CT in a patient with peripancreatic abscess. The septic thrombosis of portal vein (STPV) extended from the level of porta hepatis into the intrahepatic branches, but the portal vein and superior mesenteric vein at the level of pancreatic head were preserved with no evidence of thrombosis angiographically. The gas-containing abscess near the head of the pancreas extended toward the hepatic hilum and surrounded the portal vein and its branches on CT. It was concluded that these thrombi of portal vein branches at porta hepatis and intrahepatic branches were caused by extensions of peripancreatic abscess via the hepatoduodenal ligament and ligamentum teres. Computed tomography was useful in depicting the ligamentous spread of peripancreatic abscess resulting in STPV.

Abscess↗
PubMed1999

A high incidence of apolipoprotein E epsilon4 allele in middle-aged non-demented subjects with cerebral amyloid beta protein deposits.

We examined the apolipoprotein E (ApoE) genotypes of 19 middle-aged non-demented subjects with cerebral amyloid beta protein (Abeta) deposits, and compared the results with those of 16 patients with sporadic Alzheimer's disease (AD) and those of 34 age-matched controls. The frequency of the ApoE epsilon4 allele was higher (P = 0.0256) in these 19 subjects (0.211) than in controls (0.059), and was close to that in AD patients (0.281). This result suggests that middle-aged non-demented subjects with cerebral Abeta deposits are at high risk of developing AD, and that the diffuse Abeta deposits in these cases represent an early stage of AD pathology. We speculate that in the majority of late-onset sporadic AD patients, cerebral Abeta deposition commences when these patients are in their forties or fifties, and that the pathological process progresses gradually, taking 20 to 30 years for clinical manifestation of dementia.

Adult↗
PubMed1999

Cloning and expression of yellowtail ascites virus segment A.

cDNA of yellowtail ascites virus (YAV) segment A encoding a polyprotein of VP2, NS, and VP3 has been cloned. Comparison of the nucleotide and the deduced amino acid sequences showed very high homology between YAV and other aquatic birnaviruses. The two small open reading frames (VP5) besides the 5' terminus of the VP2 gene were found on segment A of YAV. Proteins encoded by cDNAs from segment A and the serotype-specific epitope region on VP2 were expressed using a baculovirus vector. Western blot analysis confirmed that a polyprotein was expressed and processed into VP2 and VP3 in insect cells infected with the recombinant baculovirus containing the complete polyprotein coding region. In the case of expression in silkworm larvae, only VP3 was detected in hemocytes and fat body of silkworm larvae infected with the recombinant virus. The recombinant fusion protein consisting of VP2 epitope region and polyhedrin was expressed in insect cells and cross-reacted with a mouse monoclonal antibody against VP2 which had a neutralizing activity to YAV.

Amino Acid Sequence↗
PubMed1999

Healing of the intimal dissection of the internal thoracic artery graft.

We report healing of the intimal dissection of an internal thoracic artery graft. Triple coronary artery bypass grafting was performed using left internal thoracic artery and saphenous vein grafts. One month after operation, the intimal dissection of the internal thoracic artery graft was clearly visible by coronary angiography; however, after 1 year of only medical treatment consisting of warfarin, ticlopidine, and nitrate, the intimal dissection was undetectable by coronary angiography.

Aged↗
PubMed1999

Iodine-impregnated drapes enable recording of precordial electrocardiogram.

Although we believed that the use of a polyester film drape for primary elective open sternum with delayed sternal closure made it impossible to record precordial electrocardiograms on the drape, we confirmed that it is possible to record electrocardiograms on an iodine-impregnated drape due to the iodine anion electrical conductibility.

Electric Conductivity↗
PubMed1999

Intrapulmonary lymph nodes: CT and pathological features.

Intrapulmonary lymph nodes are not uncommon and may be seen frequently in high quality computed tomography (CT) images and chest radiographs. We report four patients, older than 55 years, who had a long history of heavy smoking. Four intrapulmonary lymph nodes were located in the subpleural region (within 3 mm of the visceral pleural surface) of the right or left lower lobes. The lymph nodes were ovoid or round, homogeneous, well-defined and ranged from 9 to 10 mm in diameter. In one case, coexistent small nodules in the same or in other lobes on initial CT studies increased slightly in size over the following 3 years. All nodules contained lymphoid follicles and anthrocotic pigment, and in one case adjacent small aggregates of lymphocytes along interlobular septa were seen. Intrapulmonary lymph nodes have non-specific CT and clinical features. Follow-up CT may be useful in patients with suspected intrapulmonary lymph nodes.

Aged↗
PubMed1999

Prevention of ischemia-induced hippocampal neuronal damage by 2-deoxy-D-glucose in gerbils.

It has been reported that delayed neuronal death (DND) in the hippocampus following transient forebrain ischemia is associated with internucleosomal DNA fragmentation, indicating apoptosis. This suggests that the process of DND is energy dependent. Transient severe forebrain ischemia was induced in Mongolian gerbils by bilateral occlusion of the common carotid arteries. Post-ischemic administration of 2-deoxy-D-glucose (2-DG), a glucose antimetabolite, markedly reduced the occurrence of ischemia-induced DNA fragmentation and DND in the hippocampus. These results suggest that the reduction of energy dependent metabolism after ischemia may be an attractive therapeutic strategy for preserving hippocampal neurons vulnerable to ischemia.

Animals↗
PubMed1999

Prediction of alpha-blocker response in men with benign prostatic hyperplasia by magnetic resonance imaging.

OBJECTIVES: To assess the value of magnetic resonance imaging (MRI) for predicting the alpha-blocker response in men with symptomatic benign prostatic hyperplasia (BPH) and to examine the relationship between MRI and the area density of smooth muscle cells in BPH. METHODS: Twenty-eight men were consecutively enrolled in this study and received tamsulosin 0.2 mg once daily for 4 to 6 weeks. The efficacy of tamsulosin was determined by measuring improvements in the maximum urinary flow rate (Qmax) and International Prostate Symptom Score (IPSS). The patients underwent T2-weighted MRI and were separated into a high (H) or iso-low (IL) group according to the signal intensity of the inner gland of the prostate compared with that of bone marrow of the proximal femur head. The area density of smooth muscle cells was determined using immunostaining with antiactin antibody in 16 prostate specimens. RESULTS: IPSS significantly decreased after the administration of tamsulosin from 16 +/- 1 to 8 +/- 1 (n = 28, P <0.0001 ), and 76.7% of the patients had an improved IPSS of 25% or greater. Qmax was significantly increased in group IL (P = 0.03) but not in group H. Of the patients in group IL, 53.3% had a Qmax response (an increase of Qmax of 30% or more); 15.4% did so in group H (P = 0.04). The area density of smooth muscle cells was 48.1 +/- 3.7% in group IL (n = 9) and 36.7 +/- 3.2% in group H (n = 7, P = 0.04). CONCLUSIONS: MRI is useful in estimating the area density of smooth muscle cells in the prostate and in predicting Qmax response for alpha-blocker therapy in patients with symptomatic BPH.

Adrenergic alpha-Antagonists↗
PubMed1999

Genetics of Parkinson's disease.

Here we review familial Parkinson's disease from clinical, as well as molecular genetic aspects. To date, two genes responsible for familial Parkinson's disease have been identified: one is the alpha-synuclein gene located in the long arm of chromosome 4, and the other is the parkin gene located in the long arm of chromosome 6. The mode of inheritance of the former is autosomal dominant and clinical features consist of levodopa-responsive parkinsonism; the age of onset is younger than that of the sporadic cases (in their 40s), and the progression is faster (average disease duration approximately nine years). The latter form is transmitted as an autosomal recessive, and clinical features consist of early onset (in their 20s), levodopa-responsive parkinsonism, and a slow progression of the disease. In addition, the tau gene has been shown to be the disease gene for familial frontotemporal dementia and parkinsonism linked to chromosome 17. There are many other clinical phenotypes of familial Parkinson's disease among which three forms have been mapped to certain chromosome loci: one is in the short arm of chromosome 2, the two other forms are in the different loci of the short arm of chromosome 4. All of them are transmitted as autosomal dominant traits manifesting levodopa responsive parkinsonism. There still exists however, other clinical phenotypes of chromosome loci which are not known. Molecular cloning of these familial Parkinson's disease genes and the elucidation of the functions of the proteins encoded will certainly contribute greatly to the investigation of the etiology and pathogenesis of more common sporadic form of Parkinson's disease.

Chromosomes, Human, Pair 4↗
PubMed1999

Neuronal apoptosis studied by a sequential TUNEL technique: a method for tract-tracing.

A novel tract-tracing procedure by using a sequential in situ terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling of DNA fragments (TUNEL) is described. This method identifies fragmented DNA transported into neuronal fibers in tissue sections of gerbil hippocampal CA1 neurons following transient forebrain ischemia. The transported DNA has been confirmed by another method, fluorescence DNA detection technique by DAPI. Many methods have been developed to study the neuroanatomical connections in the central nervous system. Principally, these techniques are based on tract-tracing studies using xenobiotics into the central nervous system. Our tract-tracing method is originated from an intrinsic marker that is produced during the apoptotic process of neurons. Furthermore, the advantage of this method is that only the selected cells undergoing apoptosis are recognized and traced to the end of the related neuronal fiber. Usually, apoptotic cells possess intact intracellular metabolic mechanisms until completion of cell death. Thus, apoptotic neurons retain the axonal transport mechanisms which enables us to detect fragmented DNA moving from nuclei to distal terminals of neuronal fibers. Since TUNEL-positive DNA movement within neuronal fibers occurs only during a limited period, it is essential that a time-course of the TUNEL technique is used to study tract-tracing of apoptotic neurons. Although this method can identify only the apical dendrites of cells that are undergoing apoptosis during the limited period, some projections of the gerbil hippocampal CA1 neurons undergoing apoptosis are clearly demonstrated.

Animals↗