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Biomedical subjects

F Matsubara

Publications and source records attributed to F Matsubara.

At least 19 recordsLinked to original sources
PubMed2005

Reentrant spin-glass transition in a dilute magnet.

We perform a large-scale Monte Carlo simulation of a dilute classical Heisenberg model with ferromagnetic nearest neighbor and antiferromagnetic next-nearest neighbor interactions. We found that the model reproduces a reentrant spin-glass transition. That is, as the temperature is decreased, the magnetization increases rapidly below a certain temperature, reaches a maximum value, and then disappears at some lower temperature. The low temperature phase was suggested to be a spin-glass phase that is characterized by ferromagnetic clusters.

Journal Article↗
PubMed2004

[Lung cancer with ground glass opacity diagnosed by transbronchial lung biopsy using an ultrathin bronchoscope and virtual bronchoscopy].

Although thoracic computed tomography (CT) screening indicated that there are many patients who have pulmonary shadow with ground glass opacity, it is sometimes difficult to obtain the appropriate specimens for histological diagnosis of such patients. We herein report a lung cancer patient with ground glass opacity who was diagnosed preoperatively by an ultrathin bronchoscope and virtual bronchoscopy. A 78-year-old female was admitted to our hospital due to bacterial pneumonia. At the admission, CT showed another abnormal small shadow in her right middle lobe. Since the shadow was not visible by fluoroscopy, we reconstructed the images of virtual bronchoscopy using the data obtained by multidetector CT. The location of the shadow was determined in the peripheral area of a dorsal branch of right B4aialpha. Then the transbronchial lung biopsy using an ultrathin bronchoscope with simultaneous CT guidance was performed. The histological findings of the biopsy specimens revealed that the shadow was highly suspicious for malignancy. Therefore, the right middle lobectomy was conducted, and the tumor was diagnosed as an adenocarcinoma. An ultrathin bronchoscope with virtual bronchoscopy is useful to diagnose a pulmonary shadow with ground glass opacity.

Aged↗
PubMed2001

Expression of p8 in human pancreatic cancer.

The p8 gene is a recently identified gene with mitogenic activity. p8 expression is induced in acute pancreatitis, pancreatic development, and regeneration. However, the expression of p8 in pancreatic cancer is not reported. We investigated p8 expression in 72 human pancreatic tissues, including 38 pancreatic cancers (PCs), by immunohistochemistry. p8 was overexpressed (positive cells >25% in 1,000 cells) in 71% (27 of 38) of PCs, but in only 17% (3 of 18) of chronic pancreatitis cases. There was no overexpression in mucinous cystadenoma or in normal pancreas. The p8 overexpression rate in PC was significantly higher than that in other conditions (P < 0.05). Reverse transcription-PCR analysis confirmed p8 mRNA overexpression (tumor/nontumor ratio >2) in 75% (3 of 4) of PCs. p8 was overexpressed also in human pancreatic cancer cell lines (MIA PaCa-2 and PANC-1). These results suggest that p8 is involved in the development of pancreatic cancer, reflecting its mitogenic activity.

Aged↗
PubMed2001

Overexpression of p8 is inversely correlated with apoptosis in pancreatic cancer.

A recently identified gene, p8, has cell growth-promoting activity and is strongly induced in acute pancreatitis. In this study, we detected p8 and single-stranded DNA (ssDNA) for apoptosis by immunohistochemistry in human pancreatic cancer. The p8 was overexpressed (>30% per 1000 cancer cells) in 26 of 44 (59%) pancreatic cancers, and apoptosis (ssDNA-positive cells >10% per 1000 cancer cells) was recognized in 18 of 44 (41%) pancreatic cancers. There was a significant inverse correlation between the p8 overexpression and apoptosis (P < 0.05). Moreover, the expression pattern of high p8 and low ssDNA was seen significantly more often in lower age (<65 years), in moderately or poorly differentiated cancers, and in node-positive cases (P < 0.05). The p8 expression and apoptosis were not significantly correlated with survival. These results suggest that p8 overexpression is involved in antiapoptotic activity and the biological characteristics of pancreatic cancer.

Aged↗
PubMed2000

Maternal active and passive smoking and fetal growth: A prospective study in Nagoya, Japan.

In order to examine the effect of maternal active and passive smoking on fetal growth, we carried out a population-based cohort study. A self-administered questionnaire was distributed to 15,207 women who notified their pregnancy from April, 1989 to March, 1991. A total of 7,411 mother-singleton infant pairs were analyzed in this study. Paternal smoking status and maternal hours exposed to environmental tobacco smoke (ETS) were used as indicators of passive smoking. Infants born to active smoking mothers were 96 g lighter, on an average, at birth than those born to non-smokers, and the relative risk for intrauterine growth retardation was 1.79 (95% confidence interval (CI) = 1.05-3.04) among active smoking mothers. Infants with smoking fathers weighted 11 g lighter, on an average, than those with non-smoking fathers, and mean birth weight of infants was reduced by 19 g among mothers exposed to ETS. The relative risk for intrauterine growth retardation in non-smoking pregnants with a smoking husband and those exposed to ETS was 0.95 (95% CI = 0.72-1.26) and 0.95 (95% CI = 0.71-1.26), respectively. Our findings indicated an adverse effect of maternal active smoking on fetal growth in Japanese pregnant population, but with small influence of maternal passive smoking.

Analysis of Variance↗
PubMed1999

Malignant mesothelioma presenting as pulmonary metastasis ahead of growth of primary tumour.

A 59-year-old woman was admitted to Houju Memorial Hospital, Ishikawa, Japan, because of cough and fever on 30 March 1997. A diagnosis of pneumonia was made and she was given antibiotics. Her symptoms improved but failed to resolve completely on antibiotic therapy. On 9 September 1997, she revisited the hospital because of bodyweight loss and malaise. There was no history of exposure to asbestos. The chest roentgenogram revealed infiltrative shadows with vague and indistinct margins suggesting inflammatory processes, which were more extensive than those investigated on her last visit. One month later, a giant tumour was detected rapidly growing from the mediastinum and open biopsy was performed. The histological examination confirmed that the tumour was a malignant mesothelioma and the intrapulmonary nodules were its metastases. This is a rare case of pulmonary metastasis being present for several months before an appearance of primary mesothelioma.

Female↗
PubMed1999

Helicobacter pylori in the natural environment.

The presence of Helicobacter pylori (H. pylori) in the natural environment has been demonstrated in a number of studies. However, its route of infection into humans is unknown. To study this further, we attempted to detect H. pylori in the natural environment in a region of Japan with a high infection rate. Tap and well water and field soil samples were collected from around the residences of subjects who had participated in an epidemiological survey in 1996. Samples of water from rivers and ponds, and specimens of flies and cow faeces were collected in the region. DNA was extracted from the water, field soil and faecal samples after selective collection of H. pylori by the immunomagnetic-bead separation technique. H. pylori-specific DNA was detected in water, field soil, flies and cow faeces by nested polymerase chain reaction (PCR), and the ureA partial sequences of the PCR products were aligned. The nucleotide sequences of the samples amplified by PCR were highly homologous (96-100%) with the H. pylori sequence in the GenBank database and the H. pylori-specific DNA sequences were highly homologous with each other. These findings suggest the existence of H. pylori in the natural environment and a possible transmission route.

Animals↗
PubMed1997

Tricuspid valve endocarditis in a non-drug addict associated with peliosis hepatis.

A 31-year-old woman was admitted because of persistent remittent fever. Tricuspid valve endocarditis due to Staphylococcus aureus was identified as the cause of fever. The patient had no history of intravenous drug abuse, oral contraceptives or predisposing cardiac disease. Huge hepatomegaly was found without any signs of congestive heart failure. Liver enzyme abnormalities were not detected throughout the entire course of therapy. The liver biopsy specimen revealed peliosis hepatis. Treatment with panipenem/betamipron was successful, although recurrent septic pulmonary embolism occurred. The cause of the huge hepatomegaly encountered in the present case may be attributable to peliosis due to severe infection.

Adult↗
PubMed1996

Expression of Bombyx family fungal protease inhibitor F from Bombyx mori by baculovirus vector.

Fungal protease inhibitor F (FPI-F) from silkworm hemolymph is a novel serine protease inhibitor of the Bombyx family. The cDNA of FPI-F was introduced into a baculovirus vector and a recombinant virus was isolated and plaque-purified. The protease inhibitory activities increased in the culture medium of insect cells and in the hemolymph of silkworms infected with the recombinant virus. Judged from the behavior on ion-exchange and reversed-phase chromatographies, amino acid compositions, amino-terminal sequences, and CD spectra, the recombinant FPI-F was identical with native FPI-F. Infection with the recombinant virus caused inhibition of larval development of the silkworm. However, the degree of the effect was different in two strains, Shinryukaku and Taiheichoan, indicating that the selection of the strain of silkworm is important in using the baculovirus expression system.

Amino Acid Sequence↗
PubMed1996

Effect of mutations on the intracellular localization of Bombyx mori cytoplasmic polyhedrosis virus polyhedrin.

We have already cloned the polyhedrin genes of the wild-type strain H Bombyx mori cytoplasmic polyhedrosis virus (BmCPV) and its mutant, strain A. In this work, polyhedrin genes of mutant BmCPV strains C1 and C2 were cloned and their nucleotide sequences were determined. The polyhedrin amino acid sequences of strains C1 and C2 were compared with that of strain H. Strains C1 and C2 contained two and three sites of mutation in their polyhedrin genes, respectively. Four amino acids (249RLLV) were added at the carboxy terminus of the polyhedrin of strain A, C1 and C2 and the corresponding polyhedrin genes were introduced into a baculovirus expression vector. Intracellular localization of expressed polyhedrin as well as the morphology and localization of polyhedra were investigated by Western blot and microscopy analysis. Recombinant baculovirus containing the polyhedrin gene of strain H produced hexahedral polyhedra in both the cytoplasm and the nucleus. However, the hexahedral polyhedra of strain A were localized only in the nucleus. Normal polyhedra were not observed in cells infected with recombinant baculoviruses expressing strain C1 or C2 polyhedrin genes, but amorphous structures were found in infected cells. Results of expression of a chimaeric luciferase-containing carboxyl-terminal sequence of strain A demonstrated that this sequence was responsible for the nuclear localization. We suggest that a mutation at the carboxy terminus of BmCPV polyhedrin led to nuclear localization of polyhedrin and that several other mutations were responsible for modification of the crystallization pattern of polyhedrin.

Amino Acid Sequence↗
PubMed1995

Cloning and expression of the gene of hemocytin, an insect humoral lectin which is homologous with the mammalian von Willebrand factor.

Invertebrate lectins play an important role in a non-specific self-defense mechanism, as invertebrates do not synthesize specific antibodies. We report the cloning of several overlapping cDNAs encoding the entire silkworm (Bombyx mori) lectin, which we propose to call hemocytin. The sequence (10477 bp) encoded 3133 amino acids. The characteristics features of the carbohydrate-recognition domain of C-type animal lectin were revealed at C-terminal sequence of hemocytin. When cDNA encoding this region was introduced into baculovirus vector, hemagglutinating activities were detected in the culture fluid of a recombinant virus-infected cells. These activities were inhibited by D-mannose, N-acetyl-D-galactosamine, and D-maltose which are haptenic saccharides of authentic hemocytin. Analysis of dot and Northern blot hybridization revealed that hemocytin gene was transcribed in hemocytes of the silkworm at larval-pupal metamorphosis and/or after the injection of Escherichia coli and lipopolysaccharide. After silkworm larvae were injected with C-terminal portion of hemocytin, aggregation of hemocytes was observed in the hemolymph. Hemocytin has significant homology with mammalian von Willebrand factor which involves in platelet adhesion to subendothelium. Also, hemocytin has a homologous region with coagulation factor V and VIII. These results suggest that hemocytin molecule is an adhesive protein and relates to hemostasis or encapsulation of foreign substances for self-defense.

Amino Acid Sequence↗
PubMed1995

Thymic carcinoma involving the thyroid gland: report of two cases.

Two new cases of thymic carcinoma involving the thyroid gland and manifesting as thyroid tumors are presented. One tumor occurred within the thyroid gland and the other totally involved the thyroid gland. Microscopically they showed lobular architecture separated by fibrous bands and consisted of solid islands of squamoid to spindled epithelial cells with whorl formation resembling Hassall's corpuscle and variable amounts of lymphocytes. The squamoid to spindled epithelial cells were positive for cytokeratin but negative for thyroglobulin and calcitonin and the majority of lymphocytes showed a T-cell phenotype. One of the two cases had been diagnosed initially as squamous cell carcinoma of the thyroid. This type of thyroid carcinoma is relatively rare, but it should be differentiated from other types of thyroid carcinomas, especially squamous cell carcinoma, medullary carcinoma, or anaplastic carcinoma of the thyroid.

Aged↗
PubMed1995

Transovarian transmission of a foreign gene in the silkworm, Bombyx mori, by Autographa californica nuclear polyhedrosis virus.

We introduced a firefly luciferase gene, expressed under control of Drosophila heat shock protein gene promoter, into Autographa californica nuclear polyhedrosis virus (AcNPV). When the 5th instar larvae of the silkworm, Bombyx mori, were inoculated with the recombinant virus, luciferase activities were detected in the virus-infected larvae and pupae, and in the newly hatched larvae of the next generation. PCR amplification and Southern blot hybridization analysis demonstrated that the luciferase gene was transmitted through at least the F2 generation. In addition, the V-cathepsin gene, encoding a cysteine protease of AcNPV, was also detected in the DNA of all individuals of the F2 generation. These results show that AcNPV can be utilized as vector for the transovarian transmission of foreign genes in the silkworm.

Animals↗
PubMed1994

A case of choledochal cyst associated with adenocarcinoma exhibiting sarcomatous features.

One complication of choledochal cyst in adulthood is the development of secondary carcinoma, usually well-differentiated adenocarcinoma. We report a case of extrahepatic bile duct carcinoma associated with choledochal cyst and presenting predominantly sarcomatous features. The patient was a 52-year-old female who presented with abdominal fullness and pain. Ultrasound (US), computed tomography (CT), and cholangiography revealed a choledochal cyst with a tumor. The resected choledochal cyst was 10 x 7.5 cm and contained a protruding, ulcerated tumor, measuring about 4.0 x 2.5 cm. Histologically, the tumor was composed of spindle-shaped or fusiform cells with occasional pleomorphic or bizarre giant cells and abundant fibrous stroma, similar to malignant mesenchymal tumors. However, further histologic and immunohistochemical examination revealed that the tumor was adenocarcinoma with prominent sarcomatous features. To our knowledge, sarcomatous change in extrahepatic bile duct carcinoma associated with choledochal cyst has not been previously described.

Adenocarcinoma↗