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Biomedical subjects

K Shimokawa

Publications and source records attributed to K Shimokawa.

At least 55 records · Page 3Linked to original sources
PubMed1997

Primary pleomorphic adenoma in posterior cranial fossa.

A 35-year-old woman had an intradural tumor in the posterior fossa adjacent to the posterior wall of the left pyramidal bone, which was totally removed and histologically diagnosed as a pleomorphic adenoma. Follow-up examination for 2 years showed no recurrence of the tumor. There was no primary lesion in any other gland of the body, and therefore there is no alternative but to conclude a "migration" of some gland cells. The pathogenesis of this tumor remains unclassified.

Adenoma, Pleomorphic↗
PubMed1997

Capillary permeability-increasing enzyme-2 from the venom of Agkistrodon caliginosus (kankoku-mamushi): activity resulting from the release of peptides from fibrinogen.

When a mixture of the purified capillary permeability-increasing enzyme-2 from agkistrodon caliginosus venom and rabbit plasma was injected into the depilated skin of the back of rabbits, the capillary permeability-increasing activity was much greater than that induced by injection of the enzyme alone. To isolate the active substance, the mixture was subjected to reversed-phase high-performance liquid chromatography. Among the active peptides, five peptides were purified and their amino acid sequences were analyzed. These peptides were derived from the amino-terminal portion of the B beta-chain of fibrinogen. After the enzyme was incubated with rabbit fibrinogen, the three peptides were purified from the incubation mixture by high-performance liquid chromatography, and their amino acid compositions and amino acid sequences were determined. From these results, it was determined the peptides were derived from the amino-terminal portion of the B beta-chain of fibrinogen. This result indicates that the increase in capillary permeability induced by the enzyme is due to the peptides released from rabbit fibrinogen.

Agkistrodon↗
PubMed1997

Silver-stained nucleolar organizer regions in adenocarcinoma of the cervix--a light and electron microscopic study.

An increase in the number of Ag-NORs has been described as a possible marker for histopathological cancer diagnosis. The ultrastructural correlation of the reaction, however, has never been elucidated. In tissue samples of the endocervix of the uterus, we compared the ultrastructural configuration of Ag-NORs with the number of Ag-NORs dots. Light microscopic studies showed that the number of Ag-NORs in adenocarcinoma cells significantly increased, but the relation to the bromodeoxyuridine labeling index was not determined. By electron microscopy, Ag-NORs were only observed in the nucleoli and the nuclear bodies of nuclei. Ag-NORs were localized on all components of the nucleolar structure, but the dense fibrillar component was the predominant site in several cases. The nuclear bodies were exclusively found in adenocarcinoma cells and were argyrophilic. A spotted distribution of Ag-NORs was often found in the nucleoli of adenocarcinoma cells that showed an increased Ag-NOR count. The number of Ag-NORs was attributed not only to the number of nucleoli and nuclear bodies in a nucleus but also to the speckled distribution of silver deposits in a nucleolus. These results imply that the Ag-NOR count is a more definitive indicator of a hyperactive state of the cells than the combined number of nucleoli and nuclear bodies in adenocarcinoma of the uterine cervix.

Adenocarcinoma↗
PubMed1997

Detection of micrometastatic prostate cancer cells in the bone marrow of patients with prostate cancer.

Thirty-five patients with prostate cancer were examined for micrometastases to the bone marrow using reverse transcription-polymerase chain reaction (RT-PCR) with primers specific for the prostate-specific antigen (PSA) gene. Of nine patients with bone metastases detectable by bone scan imaging, five patients had PSA mRNA expression in the bone marrow detectable by RT-PCR. Of 26 patients with negative bone scan findings, seven patients had PSA mRNA expression detectable in the bone marrow. RT-PCR could detect micrometastatic prostate cancer cells in the bone marrow that were not detectable by bone scan imaging. Of 16 patients with a serum PSA concentration of 25 ng ml(-1) or greater, only nine (56.3%) had bone metastases detected by bone scans. Of the remaining seven patients, five had micrometastases to the bone marrow detected by RT-PCR. Overall, 14 of 16 patients (87.5%) with a serum PSA concentration of 25 ng ml(-1) or greater had metastatic bone diseases including bone marrow micrometastases. Of 19 patients with a serum PSA concentration of less than 25 ng ml(-1), two (10.5%) had only micrometastatic disease detected by RT-PCR. A significant correlation was observed between the incidence of bone involvement and the serum PSA concentration. This study suggests that RT-PCR will potentially develop into a relevant tool to assess bone involvement including bone marrow micrometastases and establish a precise correlation between serum PSA concentration and metastatic bone disease in patients with prostate cancer.

Bone Marrow↗
PubMed1997

Cystic glucagonoma with loss of heterozygosity on chromosome 11 in multiple endocrine neoplasia type 1.

A 52-year-old man with a past history of a pituitary adenoma and hyperparathyroidism due to a parathyroid adenoma was admitted because of a solitary tumour of the pancreas revealed by ultrasonography. His family history was unremarkable. Plasma glucagon levels were slightly elevated (280 ng/l, normal range, 40-180 ng/l) with decreased plasma amino acid levels. Plasma glucagon levels disclosed an exaggerated response during an arginine infusion test and paradoxical elevation during a 75 g oral glucose tolerance test. Endoscopic ultrasonography revealed a monolocular cystic mass of about 3 cm in diameter in the body of the pancreas. A pancreatic tumour was diagnosed before surgery as a cystic glucagonoma. Intra-operative ultrasonography showed one cystic mass in the body of pancreas and two other solid tumours, about 1 cm and 0.5 cm in diameter, in the tail of the pancreas. Histologically, all three tumours showed neoplastic epithelial cells with round nuclei forming cords and/or a ribbon-like arrangement. They showed positive staining for Grimelius' silver stain and immunopositive cells for glucagon. Genetic analysis of the main cystic tumour revealed loss of heterozygosity (LOH) on chromosome 11. After the operation, the responses of plasma glucagon to arginine infusion and oral glucose became normal. Here we describe the usefulness of these provocation tests for early diagnosis and post-operative follow-up in a rare cystic glucagonoma associated with multiple endocrine neoplasia type 1 (MEN 1) which had LOH on chromosome 11.

Arginine↗
PubMed1997

A case of liver metastasis from colon cancer masquerading as focal sparing in a fatty liver.

Focal sparing in diffusely fatty liver is a well recognized entity. However, it occasionally creates some problems in the diagnosis of hepatic mass lesions. We recently experienced a case of liver metastasis from colon cancer which appeared as a wedge-shaped hyperdense area on non-enhanced CT (computed tomography). Other imaging techniques also demonstrated a wedge-shaped area which was difficult to distinguish from mere focal sparing in the fatty liver. CT arteriography and dynamic magnetic resonance images were useful for diagnosing this metastatic tumor. CT during arterial portography showed a wedge-shaped ischemic area in the anterior segment caused by intrahepatic portal vein blockade. The histological findings eventually revealed that the tumor, an adenocarcinoma, was surrounded by fibrotic tissue that mimicked focal sparing. We present the radiological features of this case and discuss how to arrive at a correct diagnosis.

Adenocarcinoma↗
PubMed1997

Immunolocalization of lipoprotein(a) in wounded tissues.

Fifty samples from inflamed tissues were examined by immunohistochemical techniques, using antibodies against apo(a), apo B, plasminogen, fibrinogen, proliferating cell nuclear antigen (PCNA), and various components of extracellular matrix. The immunohistochemical features of granulation tissues were characterized by different stages of wound healing. In the first stage, immunoreactivities for anti-apo(a) and anti-apo B were weak and focal, whereas those for anti-plasminogen and anti-fibrinogen were strong and were widespread on the tissue surface. In the second stage, granulation tissues were covered with loose fibrous connective tissue, designated as a "fibrous cap." In this stage, markedly positive staining for lipoprotein(a) [Lp(a)] was observed closer to the surface of the fibrous cap than plasminogen, suggesting that Lp(a) may prevent external fibrinolysis. Lp(a) was also found in endothelial cells and the extracellular space of small vessels underlying the fibrous cap. In the last stage of healing, apo(a) and apo B were not detectable in completely organized tissues. These findings suggest that Lp(a) plays a role in the wound healing.

Apolipoproteins B↗
PubMed1997

[A case report of localized fibrous pleural mesothelioma].

A 47-year-old female with localized fibrous pleural mesothelioma arising from the visceral pleura of S2 of rt-upper lobe is reported. We demonstrated an indirect radiographic sign of pedunculation which was the change in position of the mass with the change in patient's position. The tumor was completely extirpated with a partial resection of the adjacent lung tissues through thoracotomy. Histopathologically, the tumor consisted of collagen fibers and small amount of fibroblast. Localized fibrous mesothelioma was recognized as benign with good prognosis. However, a few cases showing recurrence after resection were reported among them. So it was considered that this patient should be followed up carefully.

Female↗
PubMed1997

[A case of esophageal leiomyoma found as mediastinal tumor, diagnosed with endoscopic ultrasonography].

A 20 year-old female was admitted to our department because of an abnormal shadow in chest roentgenogram on a physical check-up. The barium swallowing study revealed an oppression of the middle of the esophagus. Endoscopy, chest CT and MRI failed to distinguish submucosal tumor from mediastinal tumor. Endoscopic ultrasonography showed the mass originated from the esophagus and a diagnosis of esophageal smooth muscle tumor was obtained. The tumor was tried to resect by thoracoscopic surgery but was failed because of its shape like a tortoise shell. The tumor was resected through the right thoracotomy and the diagnosis was confirmed histopathologically.

Adult↗
PubMed1996

Expression, activation, and processing of the recombinant snake venom metalloproteinase, pro-atrolysin E.

The expression in human embryonic kidney (HEK 293) cells of the recombinant zymogen form (pro-) of the Crotalus atrox hemorrhagic metalloproteinase, atrolysin E, is presented. The nascent protein is comprised of pre-, pro-, proteinase-, spacer-, and disintegrin domains. The biochemical characterization of the recombinant zymogen is described along with its activation by C. atrox crude venom and other hemorrhagic toxins. Unlike the zymogen forms of the matrix metalloproteinases, pro-atrolysin E is not activated by the organomercurial, (4-aminophenyl)mercuric acetate. Pro-atrolysin E could be enzymatically activated by C. atrox crude venom, PMSF-inhibited crude venom, atrolysin A, and atrolysin E itself. There is no evidence of autoactivation. Using two polyclonal antibodies directed against the proteinase domain and the disintegrin domain of atrolysin E, the proteolytic processing of the recombinant protein by atrolysin A was followed. The first cleavage of pro-atrolysin E by atrolysin A removes the pro-domain. The second proteolysis step removes the disintegrin domain to produce the proteinase/spacer protein. These studies have identified potential activators of snake venom pro-metalloproteinases in crude venom and suggest a general scheme for the activation and processing of venom pro-metalloproteinases by the endogenous, active metalloproteinases.

Amino Acid Sequence↗
PubMed1996

Somatic alterations of the DPC4 gene in human colorectal cancers in vivo.

BACKGROUND & AIMS: The chromosome region 18q21 has been shown to be frequently deleted in colorectal cancers, and such frequent allelic loss is a hallmark of the presence of a tumor-suppressor gene. The DPC4 gene, which is located at 18q21, has been identified as a tumor-suppressor gene from examination of pancreatic cancers. The aim of the present study was to determine if it might also be altered in colorectal cancers. METHODS: Mutation analyses of the DPC4 gene were performed on complementary DNA samples from 31 primary colorectal cancer specimens using a combination of polymerase chain reaction, single-strand conformation polymorphism, and DNA sequencing. RESULTS: Four missense mutations producing amino acid substitutions and a somatic 12-base pair deletion in the coding region of the DPC4 gene were detected in the 31 cancers (16%; 5 of 31). CONCLUSIONS: The DPC4 gene may play a role as a tumor-suppressor gene in a fraction of colorectal cancers; however, while allelic loss at 18q21 is very often seen in colorectal cancers, only a minority show DPC4 mutations, suggesting that there might be another tumor-suppressor gene in this chromosome region.

Adult↗
PubMed1996

Apoptosis of lymphocytes in mice induced by infection with Rickettsia tsutsugamushi.

Histological examinations of mice infected with either a lethal (Karp) or a self-limitating (Gilliam) strain of Rickettsia tsutsugamushi were performed. Tingible body macrophages in the spleen and necrotizing lymphadenitis in regional lymph nodes were prominent only in the former. Apoptotic legions in the lymphocytes of these organs were clearly demonstrated by histochemical and electron microscopical examinations.

Animals↗
PubMed1996

[Distributions of pyrimidine nucleoside phosphorylase (PyNPase) in tissues of benign and malignant mammary diseases--immunohistochemical observations].

Pyrimidine nucleoside phosphorylase (PyNPase) is considered to be important for producing antitumor function of 5'-DFUR or 5-FU inducing compounds, since this enzyme transforms 5'-DFUR into 5-FU and 5-FU into their activated forms. Additionally, PyNPase shows high activity in various malignant tumor tissues. In this investigation, the distributions of PyNPase were examined in the tissues of mastopathy, fibroadenoma, phyllodes tumor and mammary cancer using immunohistochemical procedures. The following results were obtained. In the tissues of mastopathy or fibroadenoma, immunoreactivity was generally very weak and only a few positive epithelial cells were observed. In the phyllodes tumor, immunoreactivity was also weak, but every epithelial cell showed positive immunoreactivity. On the contrary, apparent immunoreactivity was observed in the tissues of mammary cancer, and cancer cells revealed prominent immunoreactivity.

Breast↗
PubMed1996

[Unilateral multicystic dysplastic kidney in an adult: report of a case].

A case of unilateral multicystic dysplastic kidney in a 52-year-old woman is reported. Two abnormal round-like calcifications in left upper quadrant abdomen were found on upper gastrointestinal roentgengraphy for health screening. The computerized tomographic (CT) scan revealed a very small left kidney which was not enhanced and the ring and diffuse calcifications in it. It was not visualized by drip infusion pyelography. Left nephrectomy was performed. The kidney, which was very small, had two cysts the walls of which were calcified. The left ureter and renal vessels were absent. Histological appearance shows typical multicystic dysplastic kidney (MCDK). Literature is reviewed. However, the therapy for MCDK is still controversial.

Calcinosis↗
PubMed1995

A mutation in the beta 3-adrenergic receptor gene is associated with obesity and hyperinsulinemia in Japanese subjects.

The Trp 64 Arg mutation in the beta 3-adrenergic receptor (beta 3AR) gene was investigated in 350 Japanese subjects. This mutation was not associated with non-insulin-dependent diabetes mellitus (NIDDM). In 191 subjects without NIDDM, body mass index (BMI) was significantly higher in subjects homozygous for this mutation than in those homozygous for the normal allele (24.7 +/- 1.4 vs 22.1 +/- 0.2 kg/m2, p = 0.009). Moreover, the frequency of the mutant allele in obese subjects (BMI > 26.4) was significantly higher than that in non-obese subjects (BMI < 22) (0.37 vs 0.15, p = 0.009). The presence of this mutation was also accompanied by significantly higher fasting (p = 0.000) and 2 hrs (p = 0.018) serum insulin levels during an oral glucose tolerance test. The beta 3AR may be one of the loci contributing to obesity and hyperinsulinemia/insulin resistance in Japanese subjects.

Adult↗
PubMed1995

No evidence for mutations in a putative subunit of the beta-cell ATP-sensitive potassium channel (K-ATP channel) in Japanese NIDDM patients.

The ATP-sensitive K channel (K-ATP channel) in pancreatic beta cells is believed to play a crucial role in glucose-stimulated insulin release. We investigated whether defects in the recently cloned gene for a putative subunit of this channel (KATP-2) could be a cause of diabetes in Japanese patients. The coding region of this beta-cell type channel gene was investigated in 192 diabetics with a family history of the disorder by single-stranded conformational polymorphism (SSCP) analysis. Two silent polymorphisms were found and confirmed by sequencing, but no missense or nonsense mutations were detected. The allele frequency of the polymorphisms was compared with 96 control subjects without a family history of the disease, and no clear difference was found. These results indicate that genetic defects of the KATP-2 channel may not be a major cause of diabetes in Japan.

Adult↗
PubMed1995

Successful pregnancy in a patient with pseudomyxoma peritonei arising from ovarian mucinous cystadenocarcinoma treated with cisplatin.

A 24-year-old Japanese woman clinically showing pseudomyxoma peritonei arising from ovarian mucinous cystadenocarcinoma FIGO stage Ic is reported. She received intra-abdominal administrations of cisplatin five times following left oophorectomy. After being free of disease for 6 months, she conceived and carried two pregnancies to successful deliveries at 34 and 37 weeks, respectively. At the Cesarean sections, there were no abnormal findings except for right ovarian mucinous cystadenoma. She has had no evidence of recurrence by the time of the 60-month postoperative examination.

Abdomen↗