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Biomedical subjects

A Ishikawa

Publications and source records attributed to A Ishikawa.

At least 145 records · Page 8Linked to original sources

Chondro-osseous differentiation in fat tissue tumors: magnetic resonance imaging with pathological correlation.

Chondro-osseous differentiation of three benign or malignant fat tissue tumors--two chondrolipomas and a liposarcoma with cartilaginous metaplasia--was studied with magnetic resonance (MR) imaging and compared with their pathological findings. The results suggest that demarcation of cartilage tissue can be clearly defined on MR imaging when the size of the cartilaginous area is large. Myxoid matrix, degenerative fat tissue and lipodystrophic change may decrease the delineation of the cartilage tissue.

Biopsy↗

Detection of quantitative trait loci for body weight at 10 weeks from Philippine wild mice.

A genome-wide scan for quantitative trait loci (QTLs) controlling body weight at 10 weeks after birth was carried out in a population of 387 intersubspecific backcross mice derived from a cross between C57BL/6J inbred mice (Mus musculus domesticus) and wild mice (M. m. castaneus) captured in the Philippines, in order to discover novel QTLs from the wild mice that have about 60% lower body weight than C57BL/6J. By interval mapping, we detected four QTLs: a highly significant QTL on Chromosome (Chr) 2, which was common in both sexes; two significant QTLs on Chr 13, one male-specific and the other female-specific; and a suggestive male-specific QTL on X Chr. By composite interval mapping, we confirmed the presence of the three QTLs on Chrs 2 and 13, but not of the male-specific X-linked QTL. The composite interval mapping analysis newly identified three QTLs: a significant male-specific QTL on Chr 11 and two highly significant female-specific QTLs on Chrs 9 and X. Individual QTLs explained 3.8-11.6% of the phenotypic variance, and all the QTL alleles derived from the wild mice decreased body weight. A two-way analysis of variance revealed a significant epistatic interaction between the Chr 2 QTL and the background marker locus D12Mit4 on Chr 12 only in males. The interaction effect unexpectedly increased body weight. The chromosomal region containing the Chr 2 QTL did not coincide with those of growth or fatness QTLs mapped in previous studies. These results suggest that a population of wild mice may play an important role as new sources of valuable QTLs.

Animals↗

Multiple occurrence of osteochondromas in dysplasia epiphysealis hemimelica.

Dysplasia epiphysealis hemimelica was defined by Trevor (1950) as a rare congenital growth disorder of the tarsus and of the epiphysis of the long bone. In this report, a rare case of dysplasia epiphysealis hemimelica associated with multiple extraskeletal osteochondromas is presented. Although different modes of expression of the same pathologic process have been suggested for dysplasia epiphysealis hemimelica and osteochondroma, the biological feature of cartilaginous overgrowth in the skeletal system still seems unclear.

Child↗

Intracystic hemorrhage of pancreatic serous cystadenoma after renal transplantation: report of a case.

Immunosuppressive therapy after transplantation increases the risk of developing neoplasms, and neoplasms of the digestive organs are very common in Asia. We experienced a patient with an intracystic hemorrhage of pancreatic serous cystadenoma during the follow-up after renal transplantation. Pancreatic cystadenomas are not frequent. Only two cases, presenting with acute abdomen, have so far been reported in the literature. The intracystic hemorrhage in our case may have been related to a rapid tumor growth due to weakened antitumor immunity and azathioprine-induced pancreatitis.

Adult↗

Gene expression of interstitial collagenase in both progressive and recovery phase of rat liver fibrosis induced by carbon tetrachloride.

BACKGROUND/AIMS: Liver fibrosis is a dynamic state between matrix production and degradation. Since our report in 1974, many studies have examined collagenase and liver fibrosis, but not the identification of cells responsible for collagenase production in vivo. The aim of this study was to investigate the gene expression of interstitial collagenase in the progressive and recovery phases of experimental rat liver fibrosis by in situ hybridization. METHODS: We examined the gene expression of interstitial collagenase (MMP-13) in the progressive and recovery phase of experimental rat liver fibrosis induced by chronic CCl4 intoxication by reverse transcription-polymerase chain reaction (RT-PCR) and in situ hybridization. In order to identify the cells expressing MMP-13 mRNA by in situ hybridization, immunohistochemistry was performed using serial sections. RESULTS: In normal rat liver, a faint band for MMP-13 mRNA was observed by RT-PCR, but not by in situ hybridization. The livers of rats treated with CCl4 for 4 weeks showed fatty metamorphosis but no definite fibrosis. Positive signals for MMP-13 mRNA were observed in scattered mesenchymal cells, within lobules which seem to be stellate cells from immunohistochemical staining. Once the fibrosis became prominent, the faint band for MMP-13 mRNA was detected only by RT-PCR and very few signals, if any, by in situ hybridization. On the other hand, in the recovery phase of liver fibrosis, gene expression of MMP-13 was markedly enhanced. Strong positive cells by in situ hybridization were observed mainly at the interface between the resolving fibrous septa and the parenchyma. Overlapping both images of in situ hybridization and immunohistochemical staining with the help of a computer revealed that some positive cells, but not all cells, were stellate cells stained with a-smooth muscle actin antibody. CONCLUSIONS: MMP-13 participates in the degradation of newly-formed matrix in the recovery from rat liver fibrosis more than in the remodeling of extracellular matrix for the formation of fibrosis. Hepatic stellate cells play a crucial role in MMP-13 production in the recovery from fibrosis, though not all stellate cells were positive for MMP-13 mRNA. Further investigation into gene expression of MMP-13 in recovery will lead to new strategies for the treatment of liver cirrhosis.

Animals↗

Autosomal recessive juvenile parkinsonism.

Autosomal recessive juvenile parkinsonism (AR-JP) is a hereditary neurodegenerative disorder characterized by levodopa-responsive parkinsonism with onset before age 40 years and a slowly progressive course. Families with this condition have been described predominantly in Japanese population, occasionally under different names including an autosomal recessive early-onset parkinsonism with diurnal fluctuation (AR-EPDF) or a familial form of juvenile parkinsonism. Recently, the causative gene for AR-JP was mapped on chromosome 6q25.2-q27, and subsequently a novel gene 'parkin' was identified by means of positional cloning. In this manuscript, we review the clinical, pathological and genetical aspects of AR-JP. It would not only promise to provide important insights into the molecular mechanisms of selective degeneration of dopaminergic neurons in AR-JP, but also bring insights into the mechanisms of degeneration of these neurons in Parkinson's disease.

Adolescent↗

Evaluation of balloon-occluded hepatic venography with carbon dioxide for portography and correlation between retrograde portogram and liver function in patients with liver cirrhosis.

Background/Aim: Hepatic venography with a positive-contrast medium has been reported as a method for evaluating liver disease. However, the contrast medium used in this method provides insufficient portal vein observation and may cause severe liver injuries. Carbon dioxide (CO(2)), a negative-contrast medium, may be able to depict the portal vein system with minimal hepatic toxicity. The aim of this study was to evaluate the usefulness and side-effects of balloon-occluded hepatic venography with CO(2) (CO(2) venography) and to evaluate the correlation between retrograde portogram and liver function in patients with cirrhosis. Subjects and methods: The subjects consisted of 23 biopsy-proven cirrhotic patients (male:female, 16:7; age, 58+/-12 years, range 34-80). The causes of cirrhosis were alcohol intake in ten, HCV infection in ten, HBV infection in one, primary biliary cirrhosis in one and Budd-Chiari syndrome in one. Of these patients, six were complicated with hepatocellular carcinoma (HCC). CO(2) venography was performed with an occlusion balloon catheter, and 25 ml of CO(2) was infused. CO(2) portograms were scored as follows: 0, no visualization of portal veins; 1, visualization of peripheral portal branches; 2, unilateral first portal branch; 3, bilateral first portal branches; 4, main portal vein; 5, left gastric vein, superior mesenteric vein and splenic vein. Hepatic venous pressure gradient (HVPG), cardiac functions, biochemical analysis, blood gas analysis and oxygen (O(2)) saturation monitoring were measured simultaneously. Arterio-portography was also performed. To evaluate the usefulness of CO(2) venography in patients with HCC accompanied by portal vein tumor thrombus (PVTT), three patients were also examined. Results: No significant changes in ALT, AST, O(2) saturation or blood gas data were observed after CO(2) venography. A statistically significant positive correlation was observed between CO(2) portogram scores and Child-Pugh scores (r=0.68, P=0.003). The correlations between CO(2) portogram scores and HVPG, and the forms of gastroesophageal varices in patients without PVTT and major shunts were not significant. The CO(2) portogram score was significantly higher in patients with alcoholic liver cirrhosis than in those with HCV-positive cirrhosis (P=0.04). Cavernous transformation and peripheral portal branches were demonstrated in patients with HCC accompanied by PVTT. These findings could not be observed by arterio-portography. Conclusion: CO(2) venography to obtain retrograde portogram is a safe and useful method for evaluating the portal vein system and liver function in patients with liver cirrhosis.

Journal Article↗

Mapping quantitative trait loci for circadian behavioral rhythms in SMXA recombinant inbred strains.

SM/J and A/J inbred strain of mice have different characteristics in circadian behaviors such as free-running period (tau), phase relationship (psi) between light-dark cycles and activity rhythms, and amount of wheel-running activity. To determine the genes which affect these behaviors, a quantitative trait locus (QTL) analysis using SMXA recombinant inbred strains derived from SM/J and A/J mice was performed. Concerning tau, two regions on chromosomes (Chrs) 7 and 18 surpassed the genome-wide suggestive level. As for psi, one suggestive QTL was detected on Chr 7. The QTLs which affect daily activity counts under light-dark cycles and constant darkness were mapped to the same chromosomal regions on Chrs 1 and 17, respectively. The provisional QTLs detected in the present study might be useful for understanding the complex mechanism regulating circadian behaviors.

Animals↗

Malignant intramuscular forearm tumor with overwhelming squamous element.

Squamous cell carcinoma (SCC) arising in the skeletal muscle is rare. A case of a 19-year-old female patient with an intramuscular forearm tumor showing a histopathologically overwhelming squamous element is presented. Microscopic examination revealed the classical features of SCC, including horn pearls, individual cell keratinization and intercellular bridge. A malignant spindle cell component was not detected. Neither evidence of another primary site nor skin lesion over the tumor was found and no metastatic lesion was detected in the 5 years since the appearance of the mass.

Actins↗

Low-grade intraosseous osteosarcoma in northern Japan: advantage of AgNOR and MIB-1 staining in differential diagnosis.

Low-grade intraosseous osteosarcoma is an uncommon form of bone cancer. It is occasionally difficult to recognize as a malignant tumor and is commonly misdiagnosed as a benign fibrous lesion. We retrospectively studied the records of 8 patients with low-grade intraosseous osteosarcoma in the files of the Tohoku Musculoskeletal Tumor Society in Japan. All tumors arose in the lower limb. The most common symptom was pain, with a duration exceeding 2 years in 4 patients. Radiologic findings, including those at magnetic resonance imaging (MRI), suggested malignancy in 5 lesions, whereas 3 were diagnosed as benign. Two patients initially presented with pathological fracture. The initial pathological diagnosis was malignant in 5 patients and benign in 3. All eight tumors were grade 1 in Broders' classification. The tumor showed a permeative pattern in all eight cases, but this pattern could not be confirmed in the multiple tiny fragments obtained as biopsy specimens in 3 cases. The number of silver-staining nucleolar organizer regions (AgNOR) per nucleus and MIB-1-positive rate were significantly higher in low-grade intraosseous osteosarcoma than in fibrous dysplasia, offering an advantage in differential diagnosis. Three patients (38%) developed high-grade sarcoma at the site of local recurrence after multiple intralesional excisions, and one of them died of the disease. The other 5 patients had a good clinical course after surgery with a wide margin. These findings indicate that preoperative diagnosis with radiologic investigation, including magnetic resonance (MR) imaging and histologic examination of biopsy specimens is essential in preparation for surgery with a wide margin, assuring a good clinical course, and the results of AgNOR and immunohistochemical MIB-1 staining might be helpful in differentiating low-grade intraosseous osteosarcoma from fibrous dysplasia.

Adolescent↗

Cardiac autonomic neuropathy in patients with chronic renal failure on hemodialysis.

To characterize uremic cardiac autonomic neuropathy, we measured plasma catecholamines, analyzed the 24-hour heart rate variability (HRV), and acquired serial images with (123)I-metaiodobenzylguanidine (MIBG) in 44 patients with chronic renal failure on hemodialysis and in 14 controls. Time-domain measures were calculated using the Marquette HRV program. MIBG clearance rates from the heart and lung were evaluated on planar images, and the regional MIBG uptake in the left ventricular myocardium was evaluated with single-photon emission computed tomography. Compared with controls, plasma dopamine and norepinephrine levels were elevated (p < 0.001 and p = 0.03, respectively), and all the time-domain measures of HRV were reduced in the patients (p < 0.001). The MIBG clearance rate from the heart was higher (p < 0.001), that from the lung was lower (p < 0.001), and the myocardial MIBG distribution was more heterogeneous in patients than in controls (total uptake score p </= 0.03). These variables were similar between 26 patients without and 18 patients with hypertension. Uremic cardiac autonomic neuropathy may be characterized by high plasma levels of dopamine and norepinephrine, reduced HRV, and abnormal MIBG kinetics in the heart with heterogeneous myocardial MIBG distribution, suggesting cardiac sympathetic overactivity and parasympathetic deterioration. In addition, abnormal MIBG kinetics in the lung may imply pulmonary sympathetic nervous dysfunction and/or endothelial dysfunction in uremic patients.

3-Iodobenzylguanidine↗

A telehealth project for supporting an isolated physiotherapist in a rural community of Hokkaido.

Almost all towns and villages in the rural areas of Hokkaido suffer shortages of health-care professionals, particularly therapists (e.g. physiotherapists, occupational and speech therapists). A therapist in a rural community must work as a general rehabilitation therapist. This adds to the stress of both the responsibility and the isolation and it seems to be the major reason why therapists do not generally stay in rural communities. A telehealth project to overcome this vicious circle in Hokkaido was started at Sapporo Medical University in 1997, and the town of Betsukai joined the project. This outlines the support given to an isolated physiotherapist working in Betsukai, as part of a larger rehabilitation project. Regular videoconferences helped the physiotherapist gain confidence in her work in the rural community.

Female↗

Upgrading rural Japanese nurses' respiratory rehabilitation skills through videoconferencing.

We examined the effect of distance learning on nurses' clinical skills in a rural Japanese hospital. The subject matter was respiratory rehabilitation. After one face-to-face session, who 30 min sessions were delivered by videoconferencing to staff nurses working in a 100-bed rural hospital 250 miles (400 km) from Sapporo Medical University. A self-rating questionnaire was distributed before and after the sessions. Responses were collected from 15 out of 32 nurses participating in the face-to-face session (47%). Before the first videoconferencing session, 'always use' and 'sometime use' the new skills were rated by 67% of nurses, but after the second videoconferencing session 'always use' and 'sometimes use' were rated by 73% and 'never use' at 0%. This implies that there was increased use of new skills after the second session, although the difference was not significant. The nurses' opinions about the effectiveness for patients increased from 8% to 27% after the second session, which was significant. The pilot project indicated the usefulness of distance learning for upgrading nurses' clinical practice in one rural Japanese hospital and suggested ways in which videoconferencing can be used in future.

Attitude of Health Personnel↗

Molecular cloning and characterization of a cDNA for a rice Sec31p homolog.

A cDNA for a putative Sec31p in rice has been cloned and sequenced. In yeast, Sec31p is a component of a protein-coated vesicle, COPII, which functions in the transport of cargo proteins from the endoplasmic reticulum to the cis-Golgi network. Structural similarities between yeast Sec31p and the rice putative homolog are discussed.

Amino Acid Sequence↗

Distribution of body weight, blood insulin and lipid levels in the SMXA recombinant inbred strains and the QTL analysis.

In the SMXA recombinant inbred (RI) strains, we measured body weight, blood insulin and lipid (triglyceride, total cholesterol and phospholipid) levels in each strain. In the five traits, mean values of substrains varied remarkably and showed a continuous spectrum of distribution, suggesting control by multiple genes at distinct loci for each trait. We also screened for quantitative trait loci (QTLs) involved in the five traits. Suggestive QTLs for body weight (Chromosomes 1 and 6), insulin (Chromosomes 1, 3, 10 and 17), triglyceride (Chromosomes 4 and 11) and phospholipid (Chromosome 18) levels were detected. The SMXA RI strains are unique tools for analyzing genetic factors that influence body weight, blood insulin and lipids levels.

Animals↗