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Biomedical subjects

N Terada

Publications and source records attributed to N Terada.

At least 145 records · Page 8Linked to original sources
PubMed1998

The effect of ramatroban (BAY u 3405), a thromboxane A2 receptor antagonist, on nasal cavity volume and minimum cross-sectional area and nasal mucosal hemodynamics after nasal mucosal allergen challenge in patients with perennial allergic rhinitis.

The thromboxane A2 receptor antagonist, ramatroban (BAY u 3405), was orally administered for 4 weeks at a daily dose of 150 mg (b.i.d.) to 10 patients with perennial allergic rhinitis who had a positive reaction to house dust challenge on nasal mucosa. Nasal cavity volume and minimum cross-sectional area were measured, and changes in nasal mucosal swelling were determined following allergen challenge with house dust. The influence on nasal mucosal hemodynamics was also investigated. Nasal cavity volume and minimum cross-sectional area were measured by acoustic rhinometry, and blood flow in the nasal mucosa was measured by laser Doppler flowmetry. Percent changes in values from baseline nasal cavity volume were significantly decreased by allergen challenge before ramatroban administration, but no significant decrease was noted after ramatroban administration. Similarly, percent changes in values from baseline nasal cavity minimum cross-sectional area were significantly decreased by allergen challenge before administration of ramatroban, but not after administration. Percent changes in values from baseline nasal mucosal hemodynamics were significantly increased by allergen challenge both before and after ramatroban administration, which thus had no effect on mucosal hemodynamics. These findings suggest that ramatroban might inhibit the increase in nasal mucosal swelling but has no effect on nasal mucosal hemodynamics.

Administration, Oral↗
PubMed1998

Changes in nasal responsiveness to histamine and to specific antigen after laser surgery.

An initial treatment with several kinds of anti-allergic medicines is useful for reducing nasal allergy symptoms in patients suffering from Japanese cedar pollinosis during the pollen season. Since laser surgery before the pollen season seems to have a preventive effect as well, it would be of interest to know the time course of changes in the nasal reactivity to specific and non-specific stimuli after laser surgery. In this study, we investigated the changes in the nasal reactivities to specific antigen and histamine after CO2 laser surgery. The nasal reactivities to both specific antigen and histamine were enhanced 2 weeks after the laser surgery. On the other hand, they were significantly reduced after 4 weeks. Our data strongly suggest. therefore. that laser surgery must be done more than 4 weeks before the start of the pollen season to avoid temporary enhancement of nasal allergy symptoms.

Adolescent↗
PubMed1998

Analysis of long-term results of our combination therapy for squamous cell cancer of the maxillary sinus.

Seventy-four patients between 1971 and 1982 in Period I and 32 patients between 1982 and 1987 in Period II with maxillary sinus squamous cell cancer were treated by combination therapy consisting of preoperative LINAC X-ray irradiation with 5-flourouracil intra-arterial chemotherapy followed by maxillectomy and primary reconstruction. In Period II, 21 patients received preoperative cisplatinum (CPPP) microcapsule chemoembolization and pepleomycin (PEP) i.m. and or postoperative CDDP i.v. with PEP i.m. in addition to the combination therapy administered in Period I depending on systemic conditions, tumor stage and histopathological type. Five and 10-year crude survival rates were 68.9% and 55.4%, respectively, for Period I and 71.9% and 56.3% for Period II, with no significant difference between the two trials. In 21 selected patients in Period II, who had additional chemotherapy with preoperative CDDP chemoembolization and/or postoperative i.v. infusion of CDDP with pepleomycin i.m., 5 and 10-year survival rates were 85.7% and 61.9%, respectively.

Antineoplastic Agents↗
PubMed1998

Analysis of factors affecting long-term treatment results of adenoid cystic carcinoma of the nose and paranasal sinuses.

At Akita University Hospital (from 1971 to 1987) and at Chiba University Hospital (from 1983 to 1988), 17 patients with adenoid cystic carcinoma of the nose and paranasal sinuses were treated by en bloc tumor resection followed by primary reconstruction of the maxilla. Pre- and postoperative radiation was combined in 5 and 6 patients, respectively. Ten-year cancer-free survival rates were 59.3% in the 12 patients with maxillary sinus tumors and 50% in the 4 patients with nasal tumors. One patient with a sphenoid sinus tumor died within 5 years. Ten-year cancer-free survival was affected markedly by grade of tumor extension. Among T1N0M0 and T2N0M0 patients (of which there were 1 and 7, respectively), only 1 died of unrelated causes, and 6 patients survived cancer-free for more than 10 years. However, 4 of the 6 T3N0M0 patients died, and the cause of death was distant metastasis in 2, intracranial tumor extension in 1, and unrelated causes in 1. All 3 T4N0M0 patients died, 2 due to intracranial tumor extension and 1 of unrelated causes. The cause of death was distant metastasis in 3, local recurrence in 3, 2 of whom had intracranial tumor extension, and unrelated causes in 2. Prevention of distant metastasis and intracranial tumor extension was considered to be crucial for improving treatment results after en bloc tumor resection. Preoperative radiation was thought to decrease incidence of distant metastasis. In 5 patients who had preoperative radiation. 4 survived cancer-free for more than 10 years, and only 1 patient died of unrelated cause. However. of the 6 patients who had postoperative radiation, 2 died of distant metastasis and another 2 died of intracranial tumor extension. Of the 6 patients who did not have radiation therapy, the causes of death were local recurrence in 1, distant metastasis in 1 and unrelated causes in 1. Preoperative radiation in 5 patients showed histopathologically moderate or marked degeneration and necrosis of tumors in all patients. Although the number of patients in this study is too small to allow statistical analysis of the data, our present modality of treatment for adenoid cystic carcinoma of the nose and paranasal sinuses is routine combination of preoperative full dose radiation, en bloc tumor resection and primary reconstruction, including en bloc resection of the cranial base in selected T4 patients.

Antineoplastic Agents↗
PubMed1998

Metastasis of renal cell cancer to the ethmoid sinus.

The origin of metastatic tumors in the nasal or paranasal sinuses is often renal cancer, and metastasis to the nasal or paranasal sinuses sometimes takes a long time after nephrectomy. The present paper deals with one patient with metastasis of renal cancer to the ethmoid sinus 2 years after nephrectomy. Even though many metastatic tumors originating from renal cancer develop in multiples, most metastatic tumors in the nasal or paranasal sinuses are single and treated surgically. However, even if multiple tumors are found in the nasal and paranasal region and other organs, surgery will be effective in preventing epistaxis and subsequent anemia. Also, when removing a tumor it will be effective to identify the feeding arteries of the tumor, perform embolization therapy, and clip the necessary arteries.

Blood Loss, Surgical↗
PubMed1998

Late phase response in nasal mucosa closely correlated with immediate phase reaction and hyperreactivity to histamine.

It has been suggested that the onset of the late phase response (LPR) and hyperreactivity to non-specific stimuli occurs in the lower airway. However, its relationship in the nose has not yet been studied. This study was designed to examine the mechanism of LPR and the relationship between LPR and hyperreactivity. A total of 25 Japanese cedar pollinosis patients participated in this study. On the first visit, the frequency of sneezes, weight of nasal discharge, and the nasal airway resistance (NAR) were time-dependently measured without antigen challenge. The histamine reactivity was observed after 12 h. The same protocol was used during the second to fourth visits. The frequency of sneezes, weight of nasal discharge, and NAR were measured continuously for 12 h after antigen challenge, and nasal reactivity to histamine was observed. The percent change of NAR during immediate phase response (IR) and during LPR showed a significant correlation. The frequency of sneezes and weight of nasal discharge induced by histamine were both significantly higher in the positive than in the negative LPR group. These results suggest that the chemical mediators and inflammatory cells inducing nasal swelling during IR cause, directly or indirectly, nasal swelling during LPR, and induce hyperreactivity to histamine.

Acute-Phase Reaction↗
PubMed1998

Scanning electron microscopic study of flowing erythrocytes in hepatic sinusoids as revealed by 'in vivo cryotechnique'.

The purpose of this study is to develop a method for stabilizing erythrocytes under flowing condition in living livers, as revealed by scanning electron microscopy (SEM). After the procedure of the 'in vivo cryotechnique', both freeze-substitution and subsequent t-butyl alcohol freeze-drying methods were used for preparing SEM specimens. By freeze-fracturing with a scalpel in liquid nitrogen before the freeze-substitution, better preserved surface tissues were obtained for examination. Erythrocytes in hepatic sinusoids were clearly detected without plasma components by the freeze-substitution method, and well preserved in parts where they were flowing with their original shapes. Some were accumulated in sinusoids, especially injunctioning areas of sinusoidal networks, as compared with those in narrow lumens between hepatocyte plates. Shapes of such erythrocytes were various, locating along endothelial cells. After stopping the blood supply into livers by artificial cardiac arrest, their shapes were dramatically changed into biconcaves and they became aggregated side by side to be packed in the sinusoids. The three-dimensional shapes of flowing erythrocytes in hepatic sinusoids were demonstrated for the first time by the 'in vivo cryotechnique' combined with SEM.

Animals↗
PubMed1998

Scanning electron microscopic study of erythrocyte shapes artificially jetted through tubes at different pressures by 'in vitro cryotechnique for erythrocytes'.

A new cryotechnique for examining morphological changes of human erythrocytes at different jet pressures was developed in the present study. Human fresh or stored erythrocytes passing through a tube were jetted into precooled isopentane-propane mixture (-193 degrees C), which was named as 'in vitro cryotechnique for erythrocytes'. After the cryotechnique procedure, the routine freeze-substitution method and subsequent t-butyl alcohol freeze-drying method were used for preparing the scanning electron microscopic specimens. At 100 mmHg or higher pressures of jetting, lamellar-arranged erythrocytes were observed to have elongated shapes. The more the jetting pressure increased, the fewer discoid shapes of erythrocytes were observed. This cryofixation technique could preserve the morphology of erythrocytes jetting from tubes, and provide the three-dimensional image of erythrocyte surfaces, as followed by scanning electron microscopy.

Erythrocyte Deformability↗
PubMed1998

The potential role of interleukin-13 in eosinophilic inflammation in nasal mucosa.

BACKGROUND: Recent studies have revealed that interleukin (IL)-13, as well as IL-4, causes de novo surface expression of vascular cell adhesion molecule-1 (VCAM-1) on endothelial cells of the umbilical vein and accelerates selective eosinophil migration. However, its role in allergic rhinitis remains to be clarified. Of particular interest is whether IL-13 upregulates VCAM-1 expression in human mucosal microvascular endothelial cells (HMMECs), to which eosinophils adhere in nasal mucosa. METHODS: To understand the potential role of IL-13 in eosinophilic inflammation in nasal mucosa, we examined the effects of IL-13 on the adhesiveness between HMMECs and eosinophils. RESULTS: IL-13 increased VCAM-1 expression in HMMECs, the adhesiveness of endothelial cells to eosinophils, and the transendothelial migration. On the other hand, IL-13 decreased the adhesiveness of eosinophils to HMMECs, and, as a result, accelerated eosinophil infiltration. Those effects are more potent than was those of IL-4. In addition, we also report that the amount of IL-13 in nasal mucosa was higher than that of IL-4. CONCLUSIONS: These results strongly indicate that IL-13, as well as IL-4, may be important in eosinophilic inflammation in the nasal mucosa.

Adolescent↗
PubMed1998

Renal tubular apoptosis after release of ureteral obstruction in the rat kidney.

BACKGROUND: Information concerning the mechanisms underlying recovery from hydronephrosis is limited. The frequency of apoptosis during healing from hydronephrosis was studied using a rat kidney model. METHODS: The presence of apoptosis was studied using an in situ DNA 3' end labeling method, electron microscopy, and agarose gel electrophoresis. RESULTS: The degree of apoptosis in both the medulla and cortex gradually increased during ureteral obstruction as shown by in situ DNA 3' end labeling. Release of the ureteral obstruction resulted in a further increase in the degree of apoptosis in the medulla and cortex. The increase in apoptosis in the medulla was transient and lasted for only 4 days following release, while that in the cortex continued for at least 3 weeks. Apoptosis in the glomerulus was not observed. Electron microscopy revealed cells with aggregated chromatin in compact granular masses that abutted the nuclear membrane. Following release of ureteral obstruction, DNA fragmentation characteristic of apoptosis was visible on agarose gel electrophoresis. CONCLUSION: These results suggest that apoptosis is involved in post-obstructive tubular damage in the rat kidney.

Animals↗
PubMed1998

Expression of histamine receptors in nasal epithelial cells and endothelial cells--the effects of sex hormones.

BACKGROUND: Hyperreactivity of the nasal mucosa is a characteristic of nasal allergy. During pregnancy, aggravation of nasal allergic symptoms is occasionally observed in subjects with nasal allergy. METHODS: Using the reverse transcription-polymerase chain reaction and Southern blot hybridization method, we investigated histamine H1 receptor mRNA (H1R mRNA) expressions in specimens of nasal epithelial layer obtained by scraping, as well as cultured human nasal epithelial cells (HNECs) and human mucosal microvascular endothelial cells (HMMECs). We compared the expressions on the specimens from patients with nasal allergy with those with nonallergic rhinitis or those from normal volunteers. In addition, we investigated the effects of female hormones on the H1R mRNA expressions in HNECs and HMMECs. RESULTS: H1R mRNA was detected in scraped specimens of nasal epithelial layer, as well as in HNECs and HMMECs. The mRNA expressions in nasal mucosal scraped specimens of epithelial layers and HNECs were more marked in patients with nasal allergy than in the other two groups. In addition, the present study demonstrates that the female hormones beta-estradiol and progesterone significantly increase the expressions of H1R mRNA on HNECs and HMMECs. CONCLUSION: The increase of the expressions of H1R mRNA may explain, in part, the nasal hyperreactivity to histamine observed in patients with nasal allergy. It has also been suggested that sex hormones are related to the preponderance of females in the incidence of allergic rhinitis after puberty, and that they are related, at least partially, to the aggravation of the nasal hyperreactivity symptoms during pregnancy through the enhanced expression of H1R mRNA on HNECs and HMMECs.

Adolescent↗
PubMed1998

Ultrastructural study of anionic sites in glomerular basement membranes at different perfusion pressures by quick-freezing and deep-etching method.

The ultrastructures of anionic sites in rat glomerular basement membranes (GBM) were studied at different perfusion pressures of 100, 150, 200 or 250 cm H2O by a quick-freezing and deep-etching (QF-DE) method, in addition to conventional fixation methods, using polyethyleneimine (PEI) as a cationic tracer. By the QF-DE method, three-dimensional ultrastructures at each pressure were observed more clearly than those seen on conventional ultrathin sections. When the perfusion pressures were changed from low levels to higher ones, the total thickness of GBM with anionic sites became gradually thinner. Many PEI particles were observed around filaments, not only in the laminae lucidae, but also in the lamina densa. These findings indicated the existence of anionic sites in both laminae lucidae and lamina densa of GBM. The numbers of PEI particles in the lamina rara externa were counted on conventional ultrathin sections for morphometric analyses. The numbers per unit length of GBM were significantly decreased at higher perfusion pressures (200 and 250 cm H2O) than those seen at both normal (150 cm H2O) and lower (100 cm H2O) pressures. It is concluded that the ultrastructures of anionic sites in the GBM may be changed in vivo, depending on the hemodynamics in the glomerular capillary.

Animals↗
PubMed1998

Suppression of cell proliferation and induction of apoptosis in uterine leiomyoma by gonadotropin-releasing hormone agonist (leuprolide acetate).

Cell proliferation and apoptosis in uterine leiomyoma were investigated during therapy with GnRH agonist (GnRHa). Patients with uterine leiomyomas were injected with 3.75 mg GnRHa (depot leuprolide acetate) at intervals of 4 weeks and underwent hysterectomy or myomectomy at the 2nd, 4th, 8th, 12th, or 16th week of GnRHa therapy. Tissue sections of leiomyomas from these patients and from control patients (control patients received no GnRHa therapy) were stained with the Ki-67 antibody or by an in situ DNA 3'-end labeling method, and numbers of Ki-67 immunostained cells and DNA 3'-end-labeled cells per cm2 were examined as indices of cell proliferation and apoptosis, respectively. The number of Ki-67 immunostained cells/cm2 in leiomyomas at the 2nd week of the GnRHa therapy was comparable with that of control patients. However, it decreased to a level less than one forth that of control patients at the 4th week, and it remained at similar low levels at the 8th, 12th, and 16th week. The number of DNA 3'-end-labeled cells/cm2 in leiomyomas of control patients and in leiomyomas at the 2nd, 8th, 12th, and 16th weeks of GnRHa therapy were at low levels but, at the 4th week, was at an extremely high level (about 5 times more than that of control patients). The present results indicate that GnRHa therapy suppresses cell proliferation and causes a transient increase in apoptosis in uterine leiomyomas.

Adult↗
PubMed1998

Morphological studies of glomeruli in obstructive kidneys by confocal laser scanning microscopy and quick-freezing replica method.

Morphological changes of glomeruli in obstructive kidneys were studied by using confocal laser scanning microscopy (CLSM), and quick-freezing and deep-etching (QF-DE) method. Twenty-one rabbits were divided into three groups, consisting of control, 6-hr bilateral ureteral obstruction (BUO) and 24-hr BUO. In the experimental groups, the attenuation of cell bodies, the lengthening and stretching of major processes, the cystic formation in the cytoplasm and the fusion of foot processes were observed on conventional ultrathin sections. These changes in the 24-hr BUO group were more clearly observed than those in the 6-hr BUO group. By the CLSM, cell bodies and foot processes of podocytes in the experimental groups were more intensely immunostained with anti-alpha-tubulin antibody and phalloidin-FITC. By the QF-DE method, cytoskeletons in the podocyte cell bodies and major processes were composed of numerous intermediate filaments, but distinct changes of actin filaments and microtubules were not observed in the control and experimental groups. Considering the physiological changes in BUO, the mechanical stress appeared to be brought about by hemodynamic factors rather than the change of intratubular pressure, resembling the morphological changes in experimental animals with hyperfiltration and the homeostatic adaptation of podocytes under the BUO condition.

Animals↗
PubMed1998

Can POSSUM, a scoring system for perioperative surgical risk, predict postoperative clinical course?

POSSUM, a Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity, is a scoring system which assesses perioperative surgical risks (Copeland GP et al.: Br J Surg, 1991, Vol 78, 356-360). The POSSUM scoring system consists of two categories of assessment to assess the risk of surgery. A 12-factor (age, cardiac status, pulse rate, systolic blood pressure, respiratory status, Glasgow Coma Score, serum concentration of urea, potassium and sodium, hemoglobin concentration, white cell count and findings on electrocardiography) and 4-grade physiological score (PS) were developed. This was combined with a 6-factor (type of surgical procedure, number of procedures, blood loss, peritoneal soiling, presence of malignancy and mode of surgery) and 4-grade operative severity score (OSS). The present paper attempts to validate it retrospectively. Postoperative hospitalization period and duration of antibiotics administration were both significantly correlated with OSS, but not with PS. These results suggest that the POSSUM scoring system is useful for predicting the postoperative clinical course.

Adult↗
PubMed1998

Effect of female hormones on the production of IL-4 and IL-13 from peripheral blood mononuclear cells.

In this study we compared the concentrations of IL-4, IL-13, and IFN-gamma, which were produced by human peripheral blood mononuclear cells (PBMC) in the presence or absence of preincubation with beta-estradiol or progesterone both after a specific antigen challenge and without a specific antigen challenge. The concentrations of IL-4 and IL-13 from PBMC which had been preincubated with progesterone or gamma-estradiol for 18-24 h were significantly greater than those of IL-4 and IL-13 from PBMC which had been preincubated with PBS, the control. On the other hand, the concentration of IFN-gamma from PBMC was unchanged. We were able to confirm that the female hormones beta-estradiol and progesterone, at levels similar to those occurring during pregnancy, have the ability to induce production of IL-4 and IL-13 in human mononuclear cells. These results suggest that female hormones may aggravate nasal allergy symptoms during pregnancy by increasing IgE synthesis and inducing selective eosinophil infiltration.

Cells, Cultured↗
PubMed1998

Dynamic morphology of erythrocytes revealed by cryofixation technique.

This article summarizes our research on the morphology of dynamically changed erythrocyte shapes, as revealed by electron microscopy with cryofixation techniques. Cryofixation is a better way to immobilize functioning morphology in cells and tissues than conventional fixation methods because of faster freezing time. Our cryofixation techniques were used to detect erythrocyte shapes in flow and ultrastructural changes of membrane skeletal components. This required that we develop some new preparation techniques which we called, erythrocyte-splitting method, in vivo cryotechnique or in vitro cryotechnique for erythrocytes. By using various combinations of these cryofixation techniques with freeze-fracturing, freeze-substitution or deep-etching method, the native morphology of erythrocytes under various physiological or pathological conditions could be assessed by scanning or transmission electron microscopy.

Cryopreservation↗