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Biomedical subjects

K Yanagimoto

Publications and source records attributed to K Yanagimoto.

10 recordsLinked to original sources
PubMed2004

A polymorphism of DRD2 gene and brain atrophy in methamphetamine psychosis.

Our group, Ujike et al., recently reported that the A1 allele of TaqI A polymorphism of the dopamine receptor D2 (DRD2) gene, associated with transient psychosis, significantly differs from that of patients with prolonged psychosis in methamphetamine psychosis. Therefore, we examined the association between the TaqI A polymorphism of the DRD2 gene and the brain MRI view for patients with methamphetamine psychosis. The subjects underwent brain MRI scans using the FLAIR method. Genotyping was performed by PCR-RFLP methods using genomic DNA extracted from peripheral blood by the phenol method. Ten subjects had the A1/A2 genotype, eleven subjects had the A2/A2 genotype, and no subject had the A1/A1 genotype. The domain size, including the thalamus and basal ganglia that were inside each side of the putamens, did not differ between the three groups (the A1/A2-group, the A2/A2-group, and the young healthy person group). In the comparison based on this domain, the temporal lobe tended to narrow in the A2/A2-group compared to the A1/A2-group (P = .06). The other domain (cerebrum, corpus callosum, etc.) showed no difference between the A1/A2-group and the A2/A2-group. It is suggested that in methamphetamine psychosis the TaqI A polymorphism not only regulates prolongation of psychosis symptoms but also influences the form of the temporal lobe.

Adult↗
PubMed2001

Co-expression of N-cadherin and alpha-fetoprotein in stomach cancer.

Although N-cadherin is necessary for organ formation originating in the endoderm, the expression of N-cadherin in gastric carcinoma and its role has not yet been reported. The present study was conducted to determine the pattern of immunohistochemical expression of E-cadherin and N-cadherin, using formalin-fixed, paraffin-embedded tissues from 97 primary gastric carcinomas, including 17 which were producing alpha-fetoprotein (AFP). Samples were subdivided into 50 tubular adenocarcinomas and 47 poorly differentiated adenocarcinomas. Results showed that E-cadherin was expressed in varying degrees in areas of cell adhesion between tumor cells, in 94 out of 97 cases studied. Three cases which showed no expression of E-cadherin were diagnosed as AFP-producing tumors by immunohistochemistry. Expression of N-cadherin was observed in varying degrees in the intercellular spaces between tumor cells in 11 tubular adenocarcinomas and in six poorly differentiated adenocarcinomas, including E-cadherin-negative cases, all of which were AFP positive. The present findings suggest a possible role for N-cadherin in gastric carcinoma.

Animals↗
PubMed2000

Mixed carcinoid-adenocarcinoma of the liver.

A 61-year-old man with a mixed carcinoid-adenocarcinoma of the liver is described. Microscopic examination of the lesion showed a differentiated adenocarcinoma with distinct carcinoid components that stained positively for argyrophil. The tumor cells contained serotonin granules on immunohistochemical studies. Detailed examination disclosed no primary tumor in the gastrointestinal tract or in any other organ. Resection was considered impractical because there were multiple tumors. The patient received chemotherapy six times (cisplatin 60 mg/m2, epirubicin 40 mg/ m2 per month). The multiple tumors gradually shrank. At the time of this writing, the patient is still alive. To our knowledge, this is the first reported case of mixed carcinoid-adenocarcinoma of the liver.

Adenocarcinoma↗
PubMed1999

Human cytomegalovirus infection in foci of Langerhans cell histiocytosis.

Langerhans cell histiocytosis (LCH) has been thought to be a disorder of immune regulation, and increasingly, evidence showing that the tissue damage in LCH involves lymphokines and pro-inflammatory cytokines is reported. We detected human cytomegalovirus (HCMV)-DNA in LCH cells in the foci of LCH lesions by immunohistochemistry, in situ hybridization and PCR. HCMV was detected in the nuclei and/or cytoplasm of LCH cells in 9 of 27 LCH cases by immunostaining. HCMV was probably an early antigen. In situ hybridization revealed signals for HCMV-DNA only in the nuclei of LCH cells in 10 of the 27 LCH cases. PCR analysis was performed in 20 of the LCH cases, and HCMV-DNA was detected in 7 of these. All 7 positive cases were also positive for HCMV by ISH and IHC. These findings suggested that early phase infection or reactivation of HCMV occurred in the LCH lesions. HCMV infection may be accompanied by impaired cytokine production. Our study also suggested a relationship between HCMV infection and expression of TNFalpha. In tissues affected by LCH, dermatopathic lymphadenopathy or malignant fibrous histiocytoma and in normal tissues no signals for Epstein-Barr virus-RNA were detected. These findings suggest that in some cases LCH is associated with HCMV infection.

Adolescent↗
PubMed1999

Combined clear and granular cell leiomyoma of soft tissue: evidence of transformation to a histiocytic phenotype.

AIMS: We present an unusual case of leiomyoma with a clear and granular cell pattern in which there was immunohistochemical evidence of transformation to a histiocytic phenotype. METHODS AND RESULTS: A 64-year-old man presented with mild scrotal swelling and pain. A local excision was performed after the clinical diagnosis of epidermal inclusion cyst. In the pathological specimen, another tumour nodule was identified which was composed predominantly of clear cells, with an occasional mixture of granular cells. Immunohistochemical analysis demonstrated positive staining for vimentin, lysozyme, CD68 and HAM56, but complete negativity for desmin, alpha-smooth muscle actin, HHF35, S100 protein, neurone-specific enolase and CD34. Ultrastructural study revealed dilated rough endoplasmic reticulum, glycogen granules, abundant vacuolar structures and also thin microfilaments with subplasmalemmal dense bodies. CONCLUSIONS: Based on these findings, we have interpreted it to be a rare case of leiomyoma with extensive clear cell and granular cell degeneration (combined clear and granular cell leiomyoma). This complete transformation of the immunohistochemical profile into the histiocytic phenotype has not been previously described in the literature.

Actins↗
PubMed1999

[Histological characteristics and clinical significance of Japanese prostate cancer with low levels of prostate specific antigen of 4.0 ng/ml or lower].

PURPOSE: They set a normal limit of prostate specific antigen (PSA) to 4.0 ng/ml in Tandem R assay at most institutions. We investigated clinical and histological characteristics of prostate cancer based on whole mount step-section histology of radical prostatectomy specimens, and taking notice of Japanese prostate cancer whose levels of PSA are less than 4.0 ng/ml in normal levels. MATERIALS AND METHODS: One hundred and twenty-two patients underwent radical prostatectomy for clinically resectable prostate cancer at University Hospital from February 1992 to April 1997. Clinicopathological findings were stratified according to the preoperative PSA levels in 111 patients without preoperative endocrine therapy. Immunohistochemical study for PSA was conducted in 7 randomly selected patients. RESULTS: Of the patients 22 (19.8%) had normal (4.0 ng/ml or lower) preoperative serum PSA. Mean tumor volume in this PSA range was 1.5 cm3 with one pT 0 case included. Pathologically organ confined, potentially curable disease (< pT 3) was found in 17 (77.3%) patients and extracapsular extension and seminal vesicle invasion in 5 (23.8%), respectively. No patients had positive pelvic lymph nodes. Well differentiated tumors of Gleason scores 2-4 were found in 9 (40.9%) of the patients, moderately differentiated tumors (Gleason scores 5, 6) in 5 (22.7%) and poorly differentiated histology (Gleason scores 7-10) in 7 (31.8%). Sixteen (72.7%) patients had clinically significant tumors (> 0.5 cm3, Gleason score > or = 7). All 7 patients had positive staining for PSA, but its intensity did not correlate with serum PSA levels. CONCLUSIONS: Many prostate cancers found in surgical specimens were clinically significant despite the low levels of PSA and potentially curable by definitive treatment. Age, co-morbidity and other clinicopathological variables as well as PSA levels should all be taken into account when treatment options are discussed.

Aged↗
PubMed1978

Oriented adsorption of purple membrane to cationic surfaces.

We have investigated the orientation of isolated fragments of Halobacterium halobium purple membrane (PM) adsorbed to poly-L-lysine-treated glass (PL-glass), by quanitative electron microscopy. Three lines of evidence support the conclusion that the cytoplasmic side of the membrane is preferentially absorbed. First, monolayer freeze-fracture reveals nonrandom orientation; more fracture faces (89%) are particulate than smooth. Second, the amount of each membrane surface present can be assayed using polycationic ferritin; 90% of all adsorbed membrane fragments are labeled. Third, it is possible to distinguish two surfaces, "cracked" (the extracellular surface) and "pitted" (the cytoplasmic surface) , in slowly air-dried, platinum-carbon-shadowed membranes. When applied under standard conditions, more than 80% appear cracked. Selection for the cytoplasmic by the cationic substrate suggests that the isolated PM, buffered at pH 7.4 and in the light, has a higher negative charge on its cytoplasmic surface than on its extracellular surface. Nevertheless, cationic ferritin (CF) preferentially adsorbs to the extracellular surface. Orientation provides a striking example of biomembrane surface asymmetry as well as the means to examine the chemical reactivity and physical properties of surfaces of a purified, nonvesicular membrane fragment.

Adsorption↗
PubMedDate not supplied

Response characteristics of amygdaloid neurons provoked by emotionally significant environmental stimuli in cats, with special reference to response durations.

Extracellular single or multiple neuronal activities were recorded from the basolateral portion of the amygdala of wild adult cats under an unanesthetized, freely moving condition, and neuronal responsiveness to neutral, aversive, and appetitive stimuli was studied. Of 71 units, 47 (66%) responded to some of the stimuli. The patterns of neuronal responses were classified into three types on the basis of response duration. Of the responses sampled, 9% rapidly attenuated and disappeared before termination of stimulus presentation (pattern A), 58% of responses were maintained during the period of the stimulus presentation but disappeared abruptly after termination (pattern B), and 33% of responses markedly outlasted the stimulus presentation period (pattern C). Pattern A responses habituated readily and were most prominent when neutral stimuli were presented, so this type of response was considered to underlie altering or orienting responses. Pattern B responses were observed equally for the three kinds of stimuli, and were suggested to be predominantly involved in perception of the environmental stimuli. Pattern C responses habituated least and tended to be elicited more frequently by aversive stimuli. This type of response was interpreted to reflect emotional arousal. These findings were considered to be compatible with the hypothesis that the amygdala plays an important role in converting environmental stimuli into emotions such as rage or fear.

Amygdala↗