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Biomedical subjects

T Tajima

Publications and source records attributed to T Tajima.

At least 127 records · Page 7Linked to original sources
PubMed1999

MR diagnosis of adenomyomatosis of the gallbladder and differentiation from gallbladder carcinoma: importance of showing Rokitansky-Aschoff sinuses.

OBJECTIVE: We evaluated the MR imaging features of adenomyomatosis of the gallbladder with particular emphasis on Rokitansky-Aschoff sinuses. MATERIALS AND METHODS: MR images of 17 patients with histologically proven adenomyomatosis were retrospectively reviewed. The presence of Rokitansky-Aschoff sinuses was evaluated and analyzed; four T2-weighted (fast spin-echo with a surface coil, with or without breath-holding, fast spin-echo with a phased-array coil with breath-holding, and half-Fourier rapid acquisition with relaxation enhancement with breath-holding) and two contrast-enhanced dynamic pulse sequences were studied. These six pulse sequences were separately rated on a 5-point scale by two radiologists for comparison. Interobserver differences were evaluated. Other MR findings were also analyzed. RESULTS: Among the six pulse sequences studied, three T2-weighted with breath-holding sequences were found to be superior to the other three sequences in showing Rokitansky-Aschoff sinuses. In particular, the half-Fourier rapid acquisition with relaxation enhancement was scored the highest by the two observers and received the highest kappa coefficient in our statistical analysis of the scoring. Diffuse-type adenomyomatosis typically showed early mucosal and subsequent serosal enhancement. Localized adenomyomatosis exhibited homogeneous enhancement, showing smooth continuity with the surrounding gallbladder epithelium. CONCLUSION: MR imaging may be able to provide important information in the diagnosis of adenomyomatosis.

Adenomyoma↗
PubMed1999

Vascular changes in hepatocellular carcinoma: correlation of radiologic and pathologic findings.

OBJECTIVE: Our objective was to analyze the hemodynamic properties and vascular supply changes in the carcinogenesis of hepatocellular carcinoma. MATERIALS AND METHODS: Ten nodules (nine patients) (one early, three early-advanced, and six advanced cases of hepatocellular carcinoma) less than 3 cm in diameter were selected from 45 patients (50 nodules) who underwent CT arteriography and CT during arterial portography. These images were correlated with histopathologic findings. Ratios of all microscopically counted (normal hepatic and abnormal) arteries, normal hepatic arteries, and portal veins in each nodule to those in the surrounding liver were calculated. RESULTS: Early hepatocellular carcinoma (one early case and early areas in three early-advanced cases) had low attenuation on CT arteriography and isoattenuation on CT during arterial portography. Advanced hepatocellular carcinoma (six advanced cases and advanced areas in three early-advanced cases) had high attenuation on CT arteriography and low attenuation on CT during arterial portography. In early hepatocellular carcinoma, the ratios of all arteries, normal hepatic arteries, and portal veins were 1.21 +/- 0.07, 0.60 +/- 0.07, and 0.73 +/- 0.06, respectively. In advanced hepatocellular carcinoma, the ratios were 2.66 +/- 0.26, 0.08 +/- 0.04, and 0.07 +/- 0.03, respectively. CONCLUSION: In early hepatocellular carcinoma, the combination of normal hepatic artery degeneration and preserved portal veins results in low attenuation on CT arteriography and isoattenuation on CT during arterial portography. In advanced hepatocellular carcinoma, the combination of neoplastic (abnormal) arterial development by angiogenesis and obliteration of portal veins results in high attenuation on CT arteriography and low attenuation on CT during arterial portography. These findings are a characteristic difference between early and advanced hepatocellular carcinoma.

Aged↗
PubMed1999

Genes expressed during the differentiation of pancreatic AR42J cells into insulin-secreting cells.

Pancreatic AR42J cells have the feature of pluripotency of the common precursor cells of the pancreas. Dexamethasone (Dx) converts them to exocrine cells, whereas activin A (Act) converts them into endocrine cells expressing pancreatic polypeptide. A combination of Act and betacellulin (BTC) converts them further into insulin-secreting cells. The present study identifies some of the genes involved in the process of differentiation that is induced by these factors, using the mRNA differential display and screening of the cDNA expression array. The expression levels of 7 genes were increased by Act alone, and a combination of Act and BTC increased the expression of 25 more genes. Of these, 16 represented known genes or homologues of genes characterized previously. Nine of the identified genes were unrelated to any other sequences in the database. An inhibitor of the mitogen-activated protein kinase pathway, PD098059, which blocks the differentiation into insulin-secreting cells, inhibited the expression of 18 of the 25 genes, suggesting that the proteins encoded by these genes are associated with the differentiation into insulin-producing cells. These include known genes encoding extracellular signaling molecules, such as parathyroid hormone-related peptide, cytoskeletal proteins, and intracellular signaling molecules. Identification and characterization of these differentially expressed genes should help to clarify the molecular mechanism of differentiation of pancreatic cells and the gene products that enable the beta-cells to produce insulin.

Activins↗
PubMed1999

Frequent expression of inducible nitric oxide synthase in esophageal squamous cell carcinomas.

Nitric oxide (NO) plays important biological roles in cardiovascular, nervous and immune systems, and is synthesized by nitric oxide synthase (NOS). Intracellular NO is known to cause DNA damage as a mutagen. We examined the expression of cytokine-inducible NOS (iNOS) in human esophageal squamous cell carcinomas. Weak iNOS immunoreactivity was seen in the basal and parabasal layers of non-neoplastic esophageal stratified squamous epithelium. iNOS expression was detected in 50 (87.7%) of the 57 esophageal squamous cell carcinomas, regardless of the depth of tumor invasion, histological differentiation and lymph node status. Early-stage cancers, i.e. mucosal squamous cell carcinomas, also showed significant iNOS expression. We speculate that increased iNOS expression is associated with the carcinogenesis of human esophageal cancer.

Adult↗
PubMed1999

Stromal expression of thrombospondin-1 is correlated with growth and metastasis of human gallbladder carcinoma.

Thrombospondin-1 (TSP1) is one of the extracellular matrix glycoproteins that affect cell adhesion, motility and growth. Based on its effects on tumors, TSP1 is thought to be a potential regulator of tumor growth and metastasis. In this study, we examined TSP1 expression in human gallbladder adenocarcinoma and its clinicopathological significance. TSP1 immunoreactivity was detected mainly in the cancer stroma and was observed infrequently in cancer cells. According to the TNM classification, 74.5% (29/39) of the T2 and T3 gallbladder cancers were TSP1-positive, while none (0/14) of the T1 cancers showed TSP1 expression (p<0.001). Lymph node metastasis and venous involvement were frequently found in the TSP1-positive cases (90.0% and 87.1%, respectively) of gallbladder adenocarcinoma (p<0.001). These observations suggested that TSP1 expression plays an important role in cancer cell growth and metastasis of human gallbladder adenocarcinomas, and that stromal TSP1 immunoreactivity is a good predictor of vascular involvement and lymph node metastasis.

Adenocarcinoma↗
PubMed1999

Small mucosal carcinoma of the stomach with para-aortic lymph node metastasis: a case report and review of the literature.

A 38-year-old woman presented with a mucosal gastric carcinoma measuring 0.7 x 0.5 cm and para-aortic lymph node metastasis. Radiographic and endoscopic studies showed a small depressed lesion on the anterior border of the gastric angle, which was classified as a type II c + III lesion. Histological examination of the biopsy specimen revealed a signet-ring cell carcinoma. Distal gastrectomy with wide lymph node excision was performed. Detailed study of the resected specimen revealed that the tumour was limited to the mucosa, but metastasized to both the perigastric and para-aortic lymph nodes. The patient received adjuvant immunochemotherapy postoperatively. However, multiple bone metastases developed at 3 years and she died 4 years after the operation.

Adult↗
PubMed1999

Palpability of breast tumors--correlation with ultrasonic findings.

With the recent development of high-resolution real-time ultrasonic devices and their application to clinical examination and breast screening, small non-palpable breast lesions have frequently been detected and controversy has arisen concerning their diagnosis and treatment. In order to evaluate the relationship between ultrasonic B-mode images and palpability of breast tumors, 71 breast tumors including 21 cancers were analyzed. Five basic measurements on tumor size and location were performed followed by calculation of secondary parameters of palpability. Larger size (D and W), less distance from the skin surface (S-T), less embeddedness within or more protrusion from the mammary gland (G-T) and greater relative size of tumor with respect to whole breast thickness (D/(S-P)) were found to be significantly related to greater palpability of breast tumors. Among the qualitative diagnostic criteria for breast tumors, an irregular shape, rough border, thick boundary echoes, heterogeneous internal echoes and indirect signs were statistically more frequent in palpable than non-palpable tumors, and in malignant than in benign tumors. In cases of cancer, palpability was related significantly only to size and to heterogeneous internal echoes. For early detection of breast cancer, identification of breast cancer among small non-palpable breast lesions less than 1 cm in size in ultrasonic B-mode images is considered to be essential.

Breast Neoplasms↗
PubMed1999

A case report: tumorectomy for brain metastasis of hepatocellular carcinoma.

Described here is a rare case of an operation for brain metastasis of hepatocellular carcinoma (HCC) after hepatectomy. We admitted a 45-year-old male patient complaining chiefly of a visual field disturbance and headaches. He had undergone a hepatectomy due to HCC one year prior to hospitalization. He was diagnosed with a brain metastasis with intratumoral hemorrhage. He underwent a tumorectomy and hemorrhage excision. After the surgery, his neurological symptoms improved, and he was temporarily rehabilitated. The decision to operate in this case could be questionable because the patient already had a pulmonary metastasis. Nevertheless, we concluded that local therapy for such a brain metastatic lesion would be effective in alleviating his discomforts and improving his quality of life as long as the primary lesion was under control.

Brain Neoplasms↗
PubMed1999

Autografting with peripheral blood CD34-positive cells following high-dose chemotherapy against breast cancer.

We report autologous CD34+ cell transplantation performed in 3 cases of recurrent breast cancer. The hematological recovery in these cases was assessed by comparing with that in the previous cases of autologous hematopoietic stem cell transplantation performed with the same high-dose chemotherapy regimen. Patient 1 was a 32-year-old woman with pulmonary and skeletal metastases; patient 2, a 55-year-old woman with pulmonary metastases; and patient 3, a 48-year-old woman with hepatic metastases. On day 1, cyclophosphamide 1000 mg/m2 and epirubicin 130 mg/m2 were administered concurrently with granulocyte colony-stimulating factor, and peripheral blood stem cells were harvested on days 14-16. These stem cells were processed using anti-CD34 monoclonal antibody and an immunomagnetic bead device, Isolex 300i. The high-dose chemotherapy regimen consisted of cyclophosphamide 2000 mg/m2/day, div, and thiotepa 200 mg/m2/day, div on day -5, -4, and -3. The harvested CD34+ cells numbered 3.9 +/- 2.8 x 10(6)/kg (range: 0.73-7.8/10(6)/kg), and the CFU-GM, 8.3 +/- 5.6 x 10(5)/kg (range: 1.2-15.1/10(5)/kg). After the separation, the percent of CD34+ cells was 81.9 +/- 11.6% (range: 65.8-96.4%), the CD34+ cell yield, 71.8 +/- 30.2% (range: 46.0-129.6%), and the CFU-GM yield, 48.9 +/- 9.1% (range: 35.3-62.0%). At the time of transplantation, the number of nucleated cells was 0.55 +/- 0.31 x 10(5)/kg, and that of CFU-GM, 31.2 +/- 17.8 x 10(5)/kg. Comparison of the hematological recovery in these three cases with that in patients receiving an identical high-dose chemotherapy regimen revealed recovery rates significantly faster than in patients having bone marrow transplants, and approximately identical with that in peripheral blood stem cell transplantation cases.

Adult↗
PubMed1999

A case of gastrointestinal stromal tumor of the stomach.

In a 55-year-old man, a tumor about 3 cm in diameter was detected in the upper abdomen by abdominal ultrasound screening during follow-up of chronic hepatitis C discovered in 1990. There were no symptoms and no abnormalities on physical examination. Tests for tumor markers were negative. By barium meal and gastroscopy, submucosal tumor was found on the lesser curvature of the stomach, with bridging fold in the absence of central ulceration. Biopsy revealed no tumor tissue. Under the diagnosis of submucosal tumor of the stomach, either a leiomyoma or leiomyosarcoma, partial resection of stomach was performed. Direct invasion of the surrounding organs, lymph node metastasis or distant metastasis was not observed grossly in the operation. Histologic examination of the resected specimen revealed proliferation of spindle cells and oval cells in an interlacing pattern. Immunohistochemistry for CD34, vimentin and c-kit protein was strongly positive, while smooth muscle actin, S-100 protein, desmin and p53 protein were negative. The proliferating cell nuclear antigen index was about 50%, while the MIB-1 index was < or = 1%. From these findings, this tumor was diagnosed as a gastrointestinal stromal tumor of the uncommitted type.

Follow-Up Studies↗
PubMed1998

Genetic analyses of the in vivo function of LolA, a periplasmic chaperone involved in the outer membrane localization of Escherichia coli lipoproteins.

The major outer membrane lipoprotein (Lpp) of Escherichia coli is released from the cytoplasmic membrane into the periplasm as a complex with LolA, a periplasmic chaperone, prior to the localization in the outer membrane. To determine whether or not LolA is generally involved in the outer membrane localization of lipoproteins in vivo, the chromosomal lolA gene was manipulated so as to be controlled by the lac promoter-operator. Depletion of LolA caused a severe growth defect, and impaired the outer membrane localization of Lpp and Pal, another outer membrane lipoprotein. Although LolA depletion did not immediately arrest the growth of cells lacking Lpp, disruption of the chromosomal lolA gene was lethal to the lpp strain, indicating that LolA is generally required for the outer membrane localization of lipoproteins, and therefore essential irrespective of the presence or absence of Lpp.

Bacterial Proteins↗
PubMed1998

Dose-Intensified Chemotherapy for Breast Cancer: Present and Future Prospects.

With the trend to maximize chemotherapy in breast cancer, the use of peripheral blood stem cells in addition to hematopoietic growth factors to alleviate myelosuppression caused by dose-intensified chemotherapy has been shown to be beneficial. In treatment of metastatic breast cancer, response rates and complete response rates as high as 100%and nearly 80%, respectively, have been reported. Such treatments have shown even greater promise in an adjuvant setting for high-risk breast cancer. High-dose chemotherapy studies, however, involve highly-selected patient populations who are generally compared with unselected patients, and controversy still surrounds the question of whether it is substantially superior to conventional-dose chemotherapy. There are now more than sufficient data to justify ongoing randomized trials, and the most important overall recommedation is to encourage patients to participate in these clinical trials.

Journal Article↗
PubMed1998

Swimming stress that causes hyperglycemia increases in vivo release of noradrenaline, but not acetylcholine, from the hypothalamus of conscious rats.

The effects of acute swimming stress (10 min) on noradrenaline release from the medial basal hypothalamus (MBH; consisting of the ventromedial and dorsomedial hypothalamus) and acetylcholine release from the lateral hypothalamic area (LHA) were investigated in freely moving rats by using in vivo microdialysis techniques. Serum glucose, noradrenaline and adrenaline concentrations were also determined. Acute swimming stress produced significant hyperglycemia, with increases in serum noradrenaline and adrenaline concentrations. The release of noradrenaline from the MBH was significantly stimulated during the swimming stress. On the other hand, the swimming stress has no significant effect on the release of acetylcholine from the LHA. These findings support the idea that hypothalamic noradrenergic neurons play an important role in the sympathoadrenal hyperglycemic response to stressful stimuli. Moreover, it is suggested that hypothalamic cholinergic neurons are not involved in the responses of serum glucose, noradrenaline and adrenaline concentrations to swimming stress.

Acetylcholine↗
PubMed1998

Immunotherapy and combined assay of serum levels of carcinoembryonic antigen and acute-phase reactants.

Our previous studies have revealed that gastric and esophageal cancer patients with abnormal sialic acid levels had a better response than those with normal levels if they received polysaccharide K (PSK), a nonspecific immunomodulator. Serum levels of carcinoembryonic antigen (CEA) and acute-phase reactants (APR) such as immunosuppressive acidic protein, acid-soluble glycoproteins, alpha1-antichymotrypsin, and sialic acid were analyzed in 872 gastric cancer patients who had undergone resection from March 1979 to September 1993 at the Department of Surgery of Tokai University. The patients were categorized into four groups according to the preoperative serum levels: group A had normal levels of both CEA and APR, group B had abnormal CEA and normal APR levels, group C had a normal CEA level and normal levels of one or more APR, and group D had abnormal levels of both CEA and of one or more APR. Patients in group D who received PSK showed significantly better survival than those without PSK (29.3% versus 6.9%; log-rank test, P = 0.0015; Breslow test, P = 0.0042). CEA-positive patients receiving PSK therapy exhibited a significantly better survival rate than those without PSK (38.1 % versus 18.6%; log-rank test, P = 0.0136; Breslow test, P = 0.0125). Cox's regression analysis showed that PSK therapy was significantly related to survival in group D, but not in the other groups. We conclude that the combined assay of tumor-associated factors (such as CEA) and various nonspecific reactants to the presence of cancer (such as immunosuppressive acidic protein, alpha1-antichymotrypsin, acid-soluble glycoproteins and sialic acid) provides a good set of preoperative indicators on which to base the selection of treatment for individual gastric cancer patients.

Acute-Phase Proteins↗
PubMed1998

Anemia in patients with colorectal cancer.

Although anemia is one of the signs of colorectal cancer, the relationships between histological findings and hematological findings other than hemoglobin level have not been adequately investigated. We investigated the relationship between hematological findings, serum iron, and histological findings in 358 patients (207 men and 157 women) with colorectal cancer. Their mean (+/-SD) ages were 64.3 +/- 12.4 and 63.8 +/- 13.3 years. A hemoglobin level of less than 10 g/dl was the criterion for anemia, and 20.8% of the men and 25.8% of the women met this criterion. Univariate analysis showed that carcinoma of the cecum, ascending colon, and transverse colon; large-size carcinoma, invasion beyond the proper muscle layer; positive lymph node metastasis: and clinical stage (Dukes' B, C, and D) were factors associated with high incidence of anemia. Histological type did not affect the hematological findings. Multivariate analysis showed that age, tumor site, and tumor size were significant factors related to anemia. Depth of invasion, the presence or absence of lymph node metastasis, and Dukes' classification were not significant factors. In the presence of these factors, mean corpuscular volume and mean corpuscular hemoglobin concentration values were low, and red blood cells were microcytic and hypochromic. The incidence of a low serum iron level was about twice the frequency of a hemoglobin level of less than 10 g/dl. The results of the multivariate analysis showed that none of the factors were significantly related to iron deficiency.

Adenocarcinoma↗