Search PubMed⌕ Search

Biomedical subjects

H Nagata

Publications and source records attributed to H Nagata.

At least 73 records · Page 4Linked to original sources
PubMed2000

Mitogenic activity of gelatin to murine spleen cells.

We reported previously that gelatin stimulates the growth of spleen cells in vitro. Tritium thymidine (3H-TdR) uptake into phytohemagglutinin (PHA)-stimulated spleen cells as well as intact spleen cells was augmented by gelatin. These findings suggest that gelatin serves as a mitogen for lymphoid cells. In this study, the target of action of gelatin was investigated. Tritium thymidine uptake into T cell-rich fraction was enhanced by incubation with 7.5 mg/ml of gelatin for 48 hours. The level of 3H-TdR uptake into B cell-rich fraction was not definitely increased by gelatin. Flow cytometric analysis confirmed these findings. Namely, it showed that treatment of spleen cells with 7.5 mg/ml gelatin increased a ratio of CD3-positive cells and decreased that of CD19-positive cells. Tritium thymidine uptake into natural killer cell-rich fraction was augmented by gelatin in a similar fashion to T cell-rich fraction. Tritium thymidine uptake into macrophages was very low and not affected by gelatin. Tritium thymidine uptake into macrophage-precursors was very low but was enhanced by gelatin. These findings suggest that gelatin could be used as an agent of cancer biotherapy.

Animals↗
PubMed2000

The 7alpha-methoxy substituent in cephem or oxacephem antibiotics enhances in vivo anti-Helicobacter felis activity in mice after oral administration.

The in vivo antibacterial activities of 7alpha-methoxy-cephems or 7alpha-methoxy-1-oxacephems and their demethoxy congeners after oral administration were compared in a mouse model of gastric infection with Helicobacter felis. The MICs of all four pairs of compounds with and without the 7alpha-methoxy substituent were within one two-fold dilution for H. felis and Helicobacter pylori, but the 7alpha-methoxy compounds were at least four-fold more active at bacterial eradication than their demethoxy congeners. Since these compounds are not absorbed after oral administration, they are likely to have gained direct access to the bacteria from the gastric cavity. Thus the 7alpha-methoxy substituent may enhance in vivo activity by promoting the gastric mucus permeability of the compounds or by allowing the compounds to remain longer in the gastric cavity.

Animals↗
PubMed2000

Role of vascular reflex in nasal mucosal swelling in nasal allergy.

OBJECTIVE: In patients with nasal allergy, antigen challenge on the unilateral nasal mucosa results in nasal secretion not only in the ipsilateral but also in the contralateral nasal cavities that can be inhibited almost completely by premedication with atropine sulfate. The present study was performed to elucidate if centrally mediated vascular reflex induced by antigen challenge plays a role in nasal mucosal swelling in subjects with nasal allergy. METHODS: Variations of mucosal swelling and mucosal blood flow in the ipsilateral and the contralateral nasal cavities after unilateral antigen challenge were evaluated by acoustic rhinometry and laser Doppler flowmetry in 20 patients with perennial nasal allergy. RESULTS: Unilateral antigen challenge caused ipsilateral and contralateral nasal mucosal swelling in 17 and 13 patients, respectively. Incidence of contralateral nasal mucosal swelling after unilateral antigen challenge was significantly higher compared with that after control disc challenge (P < .001). In 10 patients in whom unilateral antigen challenge caused bilateral nasal mucosal swelling, significant swelling of the nasal mucosa lasted for more than 30 minutes in the ipsilateral nasal cavity after antigen challenge compared with only 15 minutes in the contralateral nasal cavity. Peak values of contralateral mucosal swelling were 45.3% of those of ipsilateral nasal mucosa. CONCLUSIONS: Centrally mediated vascular reflex is partially involved in the onset of nasal mucosal swelling observed after antigen challenge in subjects with nasal allergy. However, nasal mucosal swelling that persists and proceeds even 20 minutes after antigen challenge is caused by the direct effects of chemical mediators on the nasal vasculature.

Adolescent↗
PubMed2000

Thermological study of drilling bone tissue with a high-speed drill.

OBJECTIVE: To perform a detailed quantitative analysis of the effect of intermittent drilling and irrigation to lower the temperature during high-speed drilling. METHODS: We examined the thermal changes for 15 bone flaps while drilling a 7- x 7-mm area for 18 seconds and a specific point for 9 seconds, under the following conditions: continuous or intermittent drilling; with a fluted steel or a diamond ball cutter; without or with irrigation, with room temperature or cold (8 degrees C) Ringer solution. RESULTS: The maximum temperature during continuous drilling with a diamond cutter (or steel cutter) was 82.4 +/- 1.3 degrees C (55.2 +/- 1.0 degrees C) without irrigation, 42.5 +/- 1.2 degrees C (35.4 +/- 0.9 degrees C) with room temperature Ringer irrigation, and 22.5 +/- 1.4 degrees C (21.6 +/- 0.3 degrees C) with cold Ringer irrigation, whereas that during intermittent drilling was 66.1 +/- 1.2 degrees C (35.6 +/- 0.8 degrees C), 35.0 +/- 0.8 degrees C (25.4 +/- 0.7 degrees C), and 21.5 +/- 0.6 degrees C (21.8 +/- 0.4 degrees C), respectively. During continuous drilling of a specific point, the radius of the concentric isothermal line for 43 degrees C (thermal threshold for neurons) was 3.6 +/- 0.8 mm with a steel cutter, and it was 8.1 +/- 0.3 mm with a diamond cutter. The radius was 4.2 +/- 0.8 mm during intermittent drilling with a diamond cutter, and it was 4.0 +/- 0.1 mm during continuous drilling with room temperature Ringer irrigation. Intermittent drilling with cold Ringer irrigation kept the temperature, even at the center of the drilled area, below 20 degrees C. CONCLUSION: Intentional intermittent drilling with irrigation reduces temperature elevation and its expansion. These procedures are necessary for safe drilling, especially with a diamond burr. Although cold irrigation can minimize temperature elevation, its substantial effect on nerves or other structures needs to be elucidated.

Adult↗
PubMed2000

Screening of BRCA1 mutation using immunohistochemical staining with C-terminal and N-terminal antibodies in familial ovarian cancers.

We examined the subcellular localization of BRCA1 proteins using immunohistochemical staining with C-terminal (GLK-2 antibody) and N-terminal (Ab-2 antibody) monoclonal antibodies in 44 familial ovarian cancers. Among these, 24 cases were associated with 13 independent germ-line mutations of BRCA1, and loss of heterozygosity (LOH) at one or more BRCA1 microsatellite markers was found in all 21 informative tumors tested. With GLK-2 antibody, cytoplasmic staining was observed in 15 of 16 tumors (93.8%) with mutation in exon 11, and BRCA1 staining was absent in 8 of 8 tumors (100%) with mutation in exons other than exon 11. When immunohistochemical staining was performed with Ab-2 antibody, both nuclear and cytoplasmic staining were observed in 14 of 16 tumors (87.5%) with mutation in exon 11. Interestingly, nuclear staining was observed in 3 of 3 tumors (100%) with mutation downstream of exon 11, even though no staining was detected in 5 of 5 tumors (100%) with mutation upstream of exon 11. On the other hand, in familial ovarian cancers without BRCA1 mutations, nuclear staining or both nuclear and cytoplasmic staining was observed in 18 of 20 specimens (90%) and 20 of 20 specimens (100%) with GLK-2 antibody and with Ab-2 antibody, respectively. These results suggest that an immunohistochemical assay in combination with employing the C-terminal and the N-terminal antibodies appears to have potential as a reliable and useful technique for the screening of BRCA1 mutations, at least to predict the status of mutation, upstream or downstream of exon 11.

BRCA1 Protein↗
PubMed2000

Novel rosette formation of murine spleen cells with autologous red blood cells.

Spleen cells of normal BALB/c mice formed rosettes with autologous red blood cells, and the formation was calcium ion dependent. Peritoneal exudate cells, bone marrow cells and thymocytes did not form such rosettes. Spleen cells were passed over a Sephadex G-10 column or incubated on a plastic surface in order to eliminate adherent cells from them. Cells obtained by both these methods were unable to form rosettes. B cell-, T cell- and natural killer cell-enriched fractions in spleen cells were unable to form rosettes either. Some of the mouse IgG subclasses suppressed rosette formation when added to its site. These are monoclonal antibodies whose specificities are directed against Aspergillus niger glucose oxidase. Moreover, Aspergillus niger glucose oxidase suppressed the rosette formation when spleen cells had been treated with it as well as when it had been added to the site of rosette formation. These findings suggest that some murine spleen cells have receptors to a structure on autologous red blood cells, which is recognized by an anti-Aspergillus niger glucose oxidase monoclonal antibody.

Animals↗
PubMed2000

Time course of changes in absorption of macromolecule through the nasal mucosa after antigen challenge in guinea pig model of allergic rhinitis.

The time course of changes in absorption of horseradish peroxidase (HRP) through the nasal mucosa after antigen challenge was evaluated in a guinea pig model of allergic rhinitis immunized with ovalbumin. Before and at 5 minutes, 4 hours, and 24 hours after nasal antigen challenge, both nasal cavities were filled with 5% HRP solution for 30 minutes, and blood was obtained to measure serum HRP levels by enzyme-linked immunosorbent assay. In immunized animals, the serum HRP levels were 2.3 times higher than those of normal controls (p<.05) before antigen challenge, which was performed 7 days after a series of nasal antigenic sensitizations. At 5 to 35 minutes after antigen challenge, the HRP levels decreased to one sixth of the prechallenge levels (p<.05), and they did not show a difference from the control levels. However, they increased markedly at 4 and 24 hours after antigen challenge (p<.01). The present study suggests that the absorption of macromolecules through the allergic nasal mucosa is enhanced markedly, depending upon the time course after antigen challenge, although it shows no apparent difference from normal controls during the dominant exudative process.

Absorption↗
PubMed2000

Differentiation of necrotic cell death with or without lysosomal activation: application of acute liver injury models induced by carbon tetrachloride (CCL4) and dimethylnitrosamine (DMN).

We investigated the relationship between DNA degradation and lysosome activity (loss of lysosomal integrity) in necrotic cell death induced by carbon tetrachloride (CCl4) and dimethylnitrosamine (DMN): coagulation necrosis and hemorrhagic necrosis, respectively. TdT-mediated dUTP-biotin nick end-labeling (TUNEL) and enzyme histochemistry for acid phosphatase were performed in both models and results were analyzed by light microscopy, electron microscopy, and confocal laser scanning microscopy (CLSM). In the CCl(4)-injected liver, TUNEL staining was closely associated with release of lysosomal enzymes into the cytoplasm, and intranuclear deposition of lysosomal enzymes took place at an early stage of subcellular damage. In the DMN-injected liver, TUNEL-positive nuclei tended to have well-preserved lysosomes and centrally localized TUNEL signals. It was assumed that acute hepatocellular damage in the CCl4-injected liver would be characterized by necrotic cell death with lysosome activation and that damage in the DMN-injected liver would be necrotic cell death without lysosome activation. In the DMN-injected liver, DNA degradation may be selectively induced in the nuclear center, in which heterochromatin (including inactive chromatin) is believed to be a target. We concluded that necrotic cell death, i.e., DNA degradation, would be at least divided into two types, with/without association with lysosome activation, represented by necrotic cell death in the CCl4-injected liver and that in the DMN-injected liver.

Acid Phosphatase↗
PubMed2000

Cowden's disease diagnosed through mucocutaneous lesions and gastrointestinal polyposis with recurrent hematochezia, unrevealed by initial diagnosis.

A 51-year-old man was admitted to our hospital because of hematochezia and painful keratotic plaques involving both hands. He had gastrointestinal polyposis, and a history of liver hemangiomas and thyroid tumor. Numerous papules on the face and papillomatosis on the oral mucosa were present. A diagnosis was made as a typical case of Cowden's disease according to the criteria proposed by Salem and Steck (J Am Acad Dermatol 8: 686, 1983). The patient was not correctly diagnosed initially in spite of typical manifestations of Cowden's disease, mainly due to his concomitant manifestations which occurred chronologically.

Diagnostic Errors↗
PubMed2000

Judgments of grammaticality of sentences with a differing number of arguments: a comparison of English and Japanese speakers.

This study explored native speakers' linguistic intuition as revealed in judging the grammaticality of sentences. Speakers of English (n = 36) and Japanese (n = 57) judged the relative grammaticality of sentences involving a verb which occurred together with one, two or three arguments. Findings showed that English speakers were more affected by the number of arguments in sentences. They judged sentences having three arguments as grammatical most often and ones having one or two arguments as grammatical less often. However, Japanese speakers gave rather similar and more grammatical judgments regardless of the number of arguments in sentences. The findings indicate a difference in tightness of argument structure in the two languages even when the sentences judged are simple sentences and they are given without any sentential context.

Adolescent↗
PubMed2000

Hyperglycemia exacerbates the effect of ischemia-reperfusion on peripheral nerve in rat.

Ischemia-reperfusion is known to induce generation of oxygen free radicals (OFRs), thereby resulting in tissue damage. To clarify the pathogenesis of diabetic neuropathy, we examined whether hyperglycemia exacerbates the effects of ischemia-reperfusion on peripheral nerves. Using light microscopy, characteristic pathological changes seen in myelin and axons of nerve fibers were classified into two types: "loose myelin" and "dark axon," respectively. After a 2-hour ischemia and 24-hour reperfusion of sciatic nerves of rats, the concentrations of lipid peroxide and "loose myelin" in the nerves were significantly increased in the diabetic rats, but not in the nondiabetic rats. Thereafter, "dark axon" was significantly increased in both diabetic and nondiabetic rats. "Loose myelin" may be increased as a result of the effects of OFRs produced by ischemia-reperfusion, which are exacerbated by hyperglycemia.

Animals↗
PubMed2000

[A case of metanephric adenoma treated with partial nephrectomy].

A 32-year-old female presented with a right renal mass detected by abdominal ultrasound examination at a routine medical check up. Computed tomography scans and magnetic resonance images revealed a solid tumor in the upper pole of the right kidney measuring 1.5 cm in diameter. Partial nephrectomy was performed on suspicion of the renal cell carcinoma. Histologically, the tumor is composed of small, uniform, epithelial cells with scant cytoplasm and hyperchromatic round nuclei that formed a tubular or glomerular-like structure. The histological diagnosis was metanephric adenoma.

Adenoma↗
PubMed2000

[Choriocarcinoma of the renal pelvis: a case report].

A 68-year-old male presented to our hospital complaining of gross hematuria. Intravenous pyelography subsequently demonstrated a left non-visualized kidney, and he was admitted for further evaluation. Cystoscopy revealed a bladder tumor around the left ureteral orifice and retrograde pyelography showed a filling defect in the left renal pelvis. The urinary cytology from the left renal pelvis indicated class IV, and the microscopic findings of a bladder biopsy demonstrated grade 1 transitional cell carcinoma. We performed transurethral resection of bladder tumor (TUR-BT) followed by left nephroureterectomy with bladder cuff. The pathological diagnosis was high grade transitional cell carcinoma with choriocarcinomatous component. After the operation, the serum human chorionic gonadotropin-beta (hCG-beta) level was slightly elevated, and the combination chemotherapy with methotrexate, vinblastine and cisplatin (MVC) was administered. Although the serum hCG-beta level fell to 0.1 ng/ml, after two courses of MVC chemotherapy, bilateral pulmonary metastases appeared in the chest X-ray with increasing hCG-beta levels. Salvage chemotherapy with cisplatin, etoposide and bleomycin (PEB) was performed. After two courses of PEB chemotherapy, the serum hCG-beta level fell to within the normal range and all pulmonary metastases disappeared.

Aged↗
PubMed2000

A discussion of anti-Aspergillus niger glucose oxidase monoclonal antibody reactivity to red blood cells of several species.

We observed that mouse spleen cells from rosettes with autologous red blood cells (RBCs) and that rosette-formation was suppressed by anti-Aspergillus niger glucose oxidase monoclonal antibody (mAb). In the present study, we investigated whether RBCs of species besides mice have the structure recognized by anti-A. niger glucose oxidase mAb by using rosette-formation and complement-mediated hemolysis. Lysates of monkey and human RBCs did not suppress rosette-formation whereas autologous (mouse), rat and sheep RBC lysates partially suppressed rosette-formation. Those lysates exerted their suppressive activity after they had been treated at 56 degrees C for 30 min. A. niger glucose oxidase also suppressed rosette-formation with or without treatment at 56 degrees C for 30 min. Alternatively, anti-A. niger glucose oxidase mAb lysed mouse, rat and sheep RBCs but not human RBCs with complement. These findings suggest that the cell surfaces of mouse, rat and sheep RBCs have a structure which can be recognized by anti-A. niger glucose oxidase mAb while the cell surfaces of monkey and human RBCs do not.

Animals↗
PubMed2000

[A comparative study on the clinical utility of cefozopran and cefpirome against complicated urinary tract infections].

Aiming at evaluating the utility of cefozopran (CZOP) against complicated urinary tract infections with the velocity of eradication of causal bacteria in early treatment and clinical efficacy by new criteria of UTIs, a comparative study was conducted using cefpirome (CPR) as the control drug. CZOP and CPR were administered by intravenous drip infusion at a dose of 1 g twice daily. The duration of treatment was for 5 days. The study method involved randomized assignment of the subjects to either group CZOP or group CPR. The results were as follows: 1. Of a total of 80 cases treated, 65 (CZOP group--32 cases, CPR group--33 cases) were evaluated for efficacy. 2. The overall clinical efficacy evaluation according to the criteria proposed by Japanese UTI Committee rated the CZOP group as 90.6% (29/32), and the CPR group as 90.9% (30/33), with no significant difference between the 2 groups. Clinical efficacy evaluated by attending physicians rated the CZOP group as 93.8% (30/32) and the CPR group as 90.9% (30/33). There was no significant difference between the 2 groups. 3. The efficacy rates to pyuria on day 2 were 26.7% and 0% for the CZOP group and the CPR group, respectively, indicating a higher efficacy rate for the former (p < 0.05). Those on after treatment were 59.4% and 54.5% for the CZOP group and the CPR group, respectively, with no significant difference between the 2 groups. 4. Regarding the bacteriological effect, the eradication rates of both groups were over 90% on day 1 and after treatment. There was no significant difference between the 2 groups. 5. Side effects occurred in 1 case (2.6%) out of 39 in the CZOP group and in 1 case (2.4%) out of 41 in the CPR group. Laboratory test value fluctuation was noted in 8 (20.5%) of 39 cases in the CZOP group and 11 (26.8%) of 41 cases in the CPR group. There was no significant difference between the 2 groups. The results indicate that CZOP achieves an early efficacy to pyuria, and is as useful as CPR against complicated urinary tract infections.

Adult↗
PubMed2000

In vivo identification of parasinus macrophages in the mesenteric lymph node.

Macrophages beneath the marginal sinus in the lymph nodes may play a role in defense against microorganism. The purpose of this study was to directly visualize the parasinus macrophages in the mesenteric lymph node. Fluorescent latex particles were injected into the appendix submucosa of rats. The mesenteric lymph node was epi-illuminated and observed with a fluorescent microscope. Fluorescent particles entered the marginal sinus of the mesenteric lymph node through the afferent lymphatic vessels, and distributed diffusely all over the marginal sinus. The particles became aggregated and interspersed 3 hr after injection, suggesting that particles were incorporated by phagocytes. The number of these particle-laden phagocytes increased up to 12 hr after injection, and then declined. Some phagocytes migrated rapidly within the marginal sinus. Morphology of these phagocytes in cell suspension was consistent with macrophages. In conclusion, we successfully visualized parasinus macrophages in vivo, which incorporated foreign bodies and migrated within the marginal sinus.

Animals↗