Biomedical subjects

T Sawada

Publications and source records attributed to T Sawada.

At least 469 records · Page 26Linked to original sources

PubMed1995

Age-related profile of neuroblastoma: a comparison of tumors detected by mass-screening with those detected clinically.

Infants with neuroblastoma are known to have a favorable prognosis compared to those over 1 year of age. However, there is little biological information about the age-related heterogeneity of neuroblastoma. We evaluated the biological profile comparing cases detected by mass screening with those detected clinically. A total of 238 patients with neuroblastoma were classified into four groups according to their age at diagnosis. Patients in group A were 0-5 months of age (n = 31). Patients in group B were detected clinically and were 6-11 months of age (n = 25). Patients in group C were 6-11 months of age and were detected by mass-screening (n = 97). Patients in group D were more than 12 months of age (n = 85). The age-related heterogeneity was evaluated by Kaplan-Meier survival analysis, several clinical markers (neuron specific enolase, ferritin, vanillylmandelic acid and homovanillic acid) at diagnosis, tumor Ha-ras p21 expression and tumor N-myc amplification. Infant neuroblastoma had unique features in comparison to neuroblastoma diagnosed over 12 months of age. Clinical outcome of the patients in groups A and C was quite favorable. Even patients with stage III or IV disease in group A had a favorable prognosis. However, stage IVs disease in group A was not necessarily associated with a good prognosis and the early death after diagnosis was also characteristic. The biological profile of tumors in group C was similar to that in group A but different from the profile in groups B and D. Tumors in group B had a biological profile intermediate between groups A and D.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗

PubMed1995

Long-term sequential changes of antibody to p40tax in HTLV-I carrier mothers and children.

Antibody to p40tax (anti-p40tax) in serum specimens obtained sequentially from a human T cell lymphotropic virus type I carrier population of mothers and children were assayed. The prevalences of anti-p40tax at the initial sampling were 88% (7/8) in children and 55% (16/29) in mothers. Two of the seven positive children lost their anti-p40tax during the investigation period, resulting in a final prevalence of 63% (5/8) in children. However, anti-p40tax status was constant in all the 22 mothers with multiple serum samples (15 remained positive and seven remained negative). A decline in the absorbance value of EIA for anti-p40tax was observed in seven of the 15 anti-p40tax positive mothers. This decline may result in the disappearance of anti-p40tax in some of them.

Adolescent↗

PubMed1995

[A case of Pasteurella multocida subsp. multocida septicemia due to cat bites in liver cirrhosis patient].

A 60-year-old male who had been suffering from liver cirrhosis was admitted to our hospital with high grade fever accompanied by right chest pain. Chest X-rays revealed a moderate amount of pleural fluid suggesting pleuritis. Multocida was isolated from the blood culture as well as the pleural fluid. Antibiotic therapy was initiated according to the drug susceptibility of the isolates. Ten days treatment was effective on the cessation of both septicemia and the clinical symptoms. Since the patient had been bitten several times by his own pet cats, their mouth swabs were taken for pathogenic investigations. Serotypes of the cats' isolates coincided with that of the patient's which consequently indicated the route of infection. P. multocida is a Gram negative coccobacillary organism that resides as normal flora in the oral cavity of animals, including dogs and cats. It has been originally known to be a causative agent for hemorrhagic septicemia in domestic animals. However, recently reports of P. multocida infections in man has been increasing due to the enlargement of pet populations. Although outbreaks of septicemia is rare, it occurs most often in immunologically compromised hosts, including patients with liver cirrhosis as in this case. Therefore, it is important to initiate an urgent antibiotic therapy in such cases. Overall, it is of utmost importance to instruct immunosuppressed patients to avoid excessive exposure to animals including pets.

Animals↗

PubMed1995

Replacement of the DR alpha chain with the E alpha chain enhances presentation of Mycoplasma arthritidis superantigen by the human class II DR molecule.

Mycoplasma arthritidis mitogen (MAM) is produced by an organism which can cause chronic proliferative arthritis in rodents. MAM possesses a typical superantigenic activity; it has the ability to activate a large panel of T cells which express specific V beta segments of the T-cell receptor. The presentation of MAM to T cells by antigen-presenting cells is mediated primarily through its binding to the major histocompatibility complex (MHC) class II E alpha chain in mice and the DR alpha chain in humans. However, MAM is much less active for human peripheral blood lymphocytes than for mouse splenocytes. It was suggested that a difference in MAM binding affinity between human and mouse class II molecules may account for their different MAM activities. To examine this possibility, we generated a panel of B-cell transfectants whose DR molecule is composed of either the DR alpha or the E alpha chain paired with a DR3 beta chain. The ability of these transfectants to present MAM to human peripheral T cells was analyzed. Our data show that transfectants expressing E alpha DR beta chimeric molecules have higher MAM-presenting activity than transfectants expressing wild-type DR alpha DR beta molecules, while the latter have higher activity in stimulating DR3-alloreactive T cells. Since both types of transfectants present MAM to T cells expressing the same T-cell receptor V beta gene families, the higher MAM-presenting activity of the E alpha transfectant is not due to its ability to interact with a different set of T cells. Furthermore, both the E alpha 1 and E alpha 2 domains contribute to this increased affinity for MAM binding. Taken together, our data suggest that there may be multiple MAM binding sites on the E alpha and DR alpha chains and residues unique to the E alpha chain may provide additional affinity for MAM.

Antigen Presentation↗

PubMed1995

Effects of hypercapnia on ECoG and oxidative metabolism in neonatal dog brain.

The effects of hypercapnia on cerebral electrical activity and mitochondrial oxidative phosphorylation were studied in the anesthetized neonatal dog by using the electrocorticogram (ECoG) and 31P-magnetic resonance spectroscopy. Three levels of hypercapnia with arterial PCO2 values of approximately 70, 100, and 140 Torr reduced the intracellular pH of the brain from 7.11 to 6.99, 6.87, and 6.76, respectively. These levels of hypercapnia also reduced ADP concentration ([ADP]) from 21.5 to 18.1, 14.8, and 12.9 microM as well as the average ECoG power output by 20, 30, and 40%. A Michaelis-Menten relationship for the mitochondrial respiratory enzymes was fitted with [ADP] and the change in the average ECoG. The result suggests that mitochondrial respiration is regulated by [ADP] and that the in vivo Michaelis-Menten constant for ADP was 21 microM, a value close to the in vitro value. The mitochondrial maximal reaction velocity was reduced by only 10% during hypercapnia and showed no relationship with the degree of acidosis, suggesting that mitochondrial respiratory enzymes are not responsible for the inhibition of the brain electrical activity.

Adenosine Diphosphate↗

PubMed1995

A case of newly diagnosed non-insulin-dependent diabetes associated with immediate-type allergy against human insulin.

A case of newly diagnosed non-insulin-dependent diabetes mellitus with immediate-type allergy against semisynthetic human insulin is reported. She experienced immediate-type allergy 2 months after initial insulin treatment. A skin test showed that she had allergy against the insulin itself but not the additives. The amino acid sequence of the semisynthetic human insulin was identical to that of endogenous native insulin and, moreover, the patient had not been treated with animal-derived insulin previously, so a structural change to the semisynthetic formulation at the injected subcutaneous site might have antigenicity. An H1 histamine blocker markedly diminished the skin reaction to insulin, and her plasma glucose and glycosylated hemoglobin AIc became well controlled. In summary, we experienced a diabetic patient with human insulin allergy at the time of initial insulin treatment, emphasizing that the possibility of human insulin allergy should be considered whenever a patient is started on insulin therapy.

Diabetes Mellitus, Type 2↗

PubMed1995

Tumor angiogenesis as a predictor of recurrence in gastric carcinoma.

PURPOSE: We investigated the correlation between tumor angiogenic activity and progression of gastric carcinoma using immunohistochemical staining with antifactor VIII-related antigen (F-VIII RAg) antibody. MATERIALS AND METHODS: One hundred twenty-four specimens resected from patients with gastric carcinoma were investigated by staining with a monoclonal antibody against F-VIII RAg. Correlations between the microvessel count (the mean number of microvessels in the five areas of highest vascular density at 200 times magnification), various clinicopathologic factors, and prognosis were studied. RESULTS: The microvessel count increased with histologic stage. The microvessel count was significantly higher in patients with lymph node metastases than in those without such metastases. Moreover, in patients with a high microvessel count (> or = 16), prognosis was significantly poorer than in those with low count (< 16). Multivariate analysis indicated that the microvessel count is an independent prognostic factor in patients with gastric cancer. According to the mode of recurrence, the frequency of hepatic metastases was significantly increased in patients with a high count. CONCLUSION: Microvessel count may be a good prognostic indicator and may be useful as a predictor for the mode of recurrence in patients with gastric carcinoma.

Adenocarcinoma↗

PubMed1995

Pathogenicity of Corynebacterium kutscheri in the Syrian hamster.

The pathogenicity of Corynebacterium kutscheri isolated for the first time from Syrian hamster was experimentally studied in hamsters. In hamsters given intramuscular (i.m.) or subcutaneous (s.c.) inoculation with 10 or 10(3) bacteria, neither clinical signs nor gross lesions were found. In those given 10(5) bacteria i.m., moderate proliferation of granulation tissue was found in the muscle of the inoculation region at necropsy. In the animals given 10(5) bacteria s.c., a nodular lesion was observed at the inoculation site 2 days post-inoculation (p.i.), but the nodules subsided gradually from 6 days p.i. and were unclear 10 days p.i. At necropsy, small abscesses were found in all the animals in this group. In those given 10(7) bacteria either i.m. or s.c., lesions were clearly observed at the inoculation site 1 to 10 days p.i., and a large abscess was noted at necropsy. The organisms were isolated only from the lesions in the groups. Agglutinating antibody in the sera was detected only in the animals given 10(5) or 10(7) bacteria. This suggests that 10(5) of C. kutscheri are needed to form localized nodular abscesses in Syrian hamsters.

Animals↗

PubMed1995

Clinical investigation of the vestibular cortex.

This study attempted to identify the vestibular cortex that is involved in the perception of vestibular vertigo in the human brain. We used single-photon emission computed tomography (SPECT) to measure regional cerebral blood flow (rCBF) in two cerebrovascular patients with nystagmus-sensation dissociation, which is known as brisk caloric nystagmus without simultaneous sensation of vertigo. Both patients had ischemic lesions involving mainly the parieto-temporal lobe in the nondominant hemisphere. It is suggested that the parieto-temporal lobe in the nondominant hemisphere contains the vestibular cortex which is a center for the perception of vertigo due to vestibular stimulation.

Aged↗

PubMed1995

Expression of basement membrane components in the dental papilla mesenchyme of monkey tooth germs--an immunohistochemical study.

The present work, which employs indirect immunoperoxidase methods, demonstrates electron microscopic localization of three major basement membrane (BM) components--type IV collagen, laminin, and heparan sulfate proteoglycan--at the early stages of odontogenesis in tooth germs of the Japanese macaque (Macaca fuscata). Intense immunostaining for each examined component occurred at the interface between the inner enamel epithelium and the dental papilla mesenchyme. At higher magnification, immunoreaction products were observed both in the lamina densa and lamina fibroreticularis. Fuzzy substances occurring very close to the lamina fibroreticularis manifested moderate immunoreactivity. In addition, immunostaining took place in the dental papilla mesenchyme. The dental papilla cells located close to the BM demonstrated immunoreactive material mainly on plasma membranes facing the BM. Reaction products were also observed in large concavities formed in some areas of the cell surfaces; and small, immunopositive vesicles occurred close to the plasma membrane. Immunoreaction products could be found in the cisternae of the rough endoplasmic reticulum of some mesenchymal cells. These findings suggest that dental papilla mesenchymal cells may produce the three major BM components and those of the components that are incorporated into the dental BM--particularly into the lamina fibroreticularis--during tooth development.

Animals↗

PubMed1995

[Incidence and serotypes of Salmonella in apparently healthy swine at slaughterhouses in Japan: 1975-1989].

To find healthy Salmonella carriers among swine, isolation of Salmonella from fresh cecum samples was attempted at slaughterhouses in Tokyo, Saitama, and Tochigi during a period of 11 years. Of a total 3,058 samples, 1,341 were collected between 1975 and 1979, and the other 1,717 between 1984 and 1989. The overall isolation rate of Salmonella was 13.3% (408 pigs). The rate was 23.1% between 1975 and 1979 and 5.7% between 1984 and 1989. A total of 1,037 isolates were identified as Salmonella and classified into 28 serotypes. These serotypes involved Salmonella typhimurium (26.1%), S. derby (25.4%), and S. london (9.5%). However, the detection rate of these serotypes varied from year to year. Two serotypes were detected from each of 37 pigs and three from a pig. Of these 38 pigs, 27 carried the serotypes of S. typhimurium or S. derby or both. The present study revealed that Salmonella carriers were highly frequent among healthy swine in Japan in 1970s, but decreased in 1980s.

Abattoirs↗

PubMed1995

Effects of vamicamide on urinary bladder functions in conscious dog and rat models of urinary frequency.

PURPOSE: To investigate the usefulness of vamicamide, (+/-)-(2R*, 4R*)-4-dimethylamino-2-phenyl-2-(2-pyridyl)valeramide, as a novel drug for the treatment of urinary frequency and incontinence. MATERIALS AND METHODS: Urinary frequency was evaluated in specially devised conscious dog and rat models by investigating the effects of the drug on urinary bladder function of these animals by cystometrography. RESULTS: In the dog model with transected hypogastric nerves, the bladder volume at micturition (bladder capacity) was less than 50% that of the sham-operated dog, and in the rat model with bilateral lesioning of nuclei basalis, a part of the brain, by ibotenic acid injection, bladder capacity was about 50% that of the sham-operated rat. Other bladder functions in both models were unchanged. In the dog model, orally administered vamicamide at 0.32 and 1.0 mg./kg. significantly increased bladder capacity and did not change residual urine volume or micturition pressure. Oxybutynin 0.10 mg./kg., one of the most popular drugs for the treatment of urinary frequency and incontinence, or atropine 0.10 mg./kg. induced significant increases in bladder capacity similarly to vamicamide at 0.32 mg./kg. In the rat model, oral vamicamide 0.32 mg./kg. also significantly increased bladder capacity and did not change micturition pressure or threshold pressure. Again, oxybutynin 0.10 mg./kg. or atropine 0.32 mg./kg. had almost the same effects as vamicamide 0.32 mg./kg. CONCLUSIONS: These findings suggest that vamicamide should be useful for the treatment of urinary frequency.

Animals↗

PubMed1995

[Contribution of carbohydrate antigens to endothelial E-selectin binding in cancer cells].

We first investigated the difference in carbohydrate antigens' expression between primary tumors and matched metastatic liver lesions of colorectal carcinomas, using immunohistochemical methods. Regarding the degree of expression, SLA, SLX and SPan-1 antigens were found to be expressed on a larger proportion of tumor cells in liver metastases than in primary tumors. Second, comparing the expression of carbohydrate antigens on highly metastatic colon cancer cell line to the parental line, the expression of SLA on the surface of highly metastatic variant was increased more intensively than the parental line. Finally, we investigated the contribution of carbohydrate antigens to endothelial E-selectin binding in colon and pancreatic cancer cells, and the results indicated that SLA might play a significant role in this binding. These findings suggest that the expression of carbohydrate antigens on the surface of cancer cells obviously contributed to E-selectin binding and also to metastatic potential.

Antigens, Tumor-Associated, Carbohydrate↗

PubMed1995

[Role of carbohydrate antigens in cell-cell and cell to extracellular matrix adhesion on pancreatic cancer].

We investigated the variable adhesiveness of pancreatic cancer cells by glycosylation inhibitor to elucidate the role of carbohydrate antigens in cell-cell and cell to extracellular matrix adhesion. Various carbohydrate antigens were strongly expressed on pancreatic cancer cell (SW1990) by ELISA, and these expression correlated to its in vitro invasiveness and in vivo metastatic potential. Cellular adhesion to Matrigel, laminin and collagen type IV and homotypic cellular aggregation in SW1990 were enhanced by reducing O-linked glycosylation with its inhibitor (Bzl-GalNAc), and these effect were reversed by additional purified mucins. These results suggested that O-linked glycoproteins on SW1990 cell surface may inhibit its adhesiveness to the substratum and aggregation properties by hindering surface receptors, and this variability of adhesiveness induced by altered glycosylation may have an another important role in highly metastatic potential of well glycosylated cancer cells.

Adenocarcinoma↗

PubMed1995

[Triple primary intracranial tumors of different cell types: a case report].

We report a case of triple intracranial tumors of different cell types without phacomatosis. The patient was a 77-year-old female who was hospitalized with left hemiparesis and vomiting. Computed tomography (CT) scans revealed a large tumor mass in the right frontal lobe and relatively small tumor masses in the medial right frontal and parietal lobes. Other tumors were also detected in the sella turcica, left sphenoidal wing, left anterior clinoidal process and left cerebellar convexity. This case was considered to be one of metastatic brain tumors, and surgery was performed for the right frontal tumor because of its mass effect. The tumor was so highly vascular that it could not be totally removed. Postoperatively, the mass effect showed a gradual increase on CT scans because of intratumoral hemorrhage and peritumoral edema. The patient's consciousness level gradually fell, and she died of pneumonia and cardiac insufficiency 1 month after the operation. The surgical specimen of the tumor was diagnosed as glioblastoma multiforme by histological examination. At autopsy, the small tumors in the medial frontal lobe and parietal lobe were found to be clearly separated from the large right frontal tumor and were diagnosed as multicentric glioblastoma multiforme. The sellar tumor revealed chromophobe pituitary adenoma and was diagnosed as a prolactinoma by immunohistochemical examination. The tumors in the left sphenoidal wing and left cerebellar convexity were diagnosed as transitional meningiomas. Multiple primary intracranial tumors of different cell types without phacomatosis are relatively rare, but almost 100 reported cases could be found in the literature.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma↗

PubMed1995

[The changes in nuclear DNA content in acquisition of a high capacity for metastasis of human cell lines].

Quantification of nuclear DNA content in cancer is considered a prognostic factor, and several investigators have demonstrated that aneuploid tumors are more aggressive than diploid tumors. In this report, we investigated the relationship between metastatic capacity and nuclear DNA content using gastric and colon cancer cell lines. We established a highly peritoneal metastatic cell line (2M-D3) from a gastric cancer cell line (2M) and a highly liver metastatic cell line (LM-H3) from colon cancer cell line (LM) in our laboratory. Both the highly metastatic cell lines have more capacity for growth and metastasis, but lower nuclear DNA content and chromosome numbers than these parental cell lines. The results indicated that metastatic capacity was inversely proportional to nuclear DNA content. We cannot provide a satisfactory explanation for this inverse correlation between metastatic capacity and nuclear DNA content, but it is supposed that each cancer cell may have suitable and stable nuclear DNA content in metastasis.

Animals↗

PubMed1995

[Malignancy of gastric cancer analyzed by the expression of thymidine phosphorylase].

In this study, the expression of thymidine phophorylase (dThdPase) was investigated immunohistochemically in 73 patients with gastric cancer. dThd Pase was mainly distributed at the apical portion, or cytoplasm of cancer cells and its expression was detected in 52 tumors (71.2%). There were no significant association among the expression of dThdPase, histologic type, depth of invasion, and lymph node metastasis. However, a significant difference was noted with respect to liver metastases. Among 73 patients, liver metastases were observed in 11 patients. dThdPase expression was detected in all of these cases with liver metastases, which was significantly more common than those without such metastases. In relation to the prognosis, patients with dThdPase-positive tumors had a significantly worse prognosis than those with dThdPase-negative tumors. In conclusion, the expression of dThdPase may be useful as a predictor of malignant potential in gastric cancer.

Adult↗

PubMed1995

[Establishment of a new scirrhous gastric cancer cell line OCUM-2M from a primary gastric tumor].

We report on the establishment and characterization of a scirrhous gastric cancer cell line, designated OCUM-2M, derived from a 49-year-old Japanese female. OCUM-2M was derived from a primary tumor of stomach taken by total gastrectomy. The cell line grew singly or in clusters in the cultured medium. The cell line continued to multiply for more than one year. Doubling time was 37.3 hours, chromosomal mode was 70. The DNA ploidy pattern was aneuploid and DNA index was 1.59. It produced several tumor-associated antigens such as CEA, CA19-9, SLX and SPan-1. The cell line was transplantable in athymic BALB/c nude mice, and histological findings of the xenografted tumor showed poorly differentiated adenocarcinoma. The growth of OCUM-2M was stimulated following the addition of EGF, b-FGF and KGF, and decreased following the addition of TGF-beta 1. This cell line is useful in vitro and in vivo systems for studies of the biology of scirrhous gastric carcinoma.

Adenocarcinoma, Scirrhous↗