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Biomedical subjects

T Iwanaga

Publications and source records attributed to T Iwanaga.

At least 163 records · Page 9Linked to original sources
PubMed1995

Intraepithelial nerve fibers in the nasal mucosa of the rat with special reference to the localization of CGRP, VIP and nitric oxide (NO).

Previous studies have demonstrated that the epithelium of the respiratory portion of rat nasal mucosa is amply supplied by nerve fibers with immunoreactivities for calcitonin gene-related peptide (CGRP) and substance P (SP), these fibers most likely acting as sensory mediators in the mucosa. The present study demonstrates that some intraepithelial fibers contain a VIP-immunoreactivity whose occurrence in these nerves has previously been neglected. The present study further aims to confirm the occurrence of NO-producing intraepithelial nerve fibers in the rat nasal mucosa and to examine its colocalization with CGRP and with VIP. Double staining methods were used to evaluate the colocalization of NADPH-diaphorase. The reactivity for NADPH-diaphorase and that for CGRP coexisted in only a small part, if any, of the nerve fibers distributed at the basal portion of the epithelium. In the perpendicularly and obliquely oriented transepithelial nerve fibers, both reactivities were clearly demonstrated to be separated in different fibers. VIP immunoreactivity was also present in a part of the intraepithelial nerve fibers of the nasal mucosa, and their entire population was shown to be positive for NADPH-diaphorase. The NADPH-diaphorase-positive reaction was displayed in only a small population of neurons in the trigeminal ganglion, whereas it was seen in numerous neurons in sphenopalatine ganglion, being colocalized with VIP.

Animals↗
PubMed1995

Nitric oxide synthase in rat nasal mucosa; immunohistochemical and histochemical localization.

The localization of nitric oxide synthase (NOS) and its cofactor, nicotinamide-adenine dinucleotide hydrogen phosphate (NADPH)-diaphorase, was examined in the nasal mucosa of the rat by immunohistochemical and histochemical methods. In addition to cryostat sections, whole mount preparations were used to examine the distribution of nerves. Both in the nasal mucosa and in associated ganglia, the distribution of NOS-immunoreactive nervous structures essentially corresponded to that of NADPH-diaphorase-positive ones. The NOS-immunopositive nerve fibers in the respiratory area of the nasal mucosa were distributed around blood vessels and in submucosal glands. Part of the respiratory area was supplied with intraepithelial arborizations of the immunopositive fibers. The epithelial cells in the respiratory area were NADPH-diaphorase positive but NOS immunoreactivity negative. In the olfactory area, the NADPH-diaphorase- and NOS-positive nerve fibers were restricted to blood vessels located deep in the submucosa. Throughout the nasal mucosa, arterial endothelium was NADPH-diaphorase positive but NOS immunoreactivity negative. Both NOS immunoreactivity and NADPH-diaphorase activity were found in major populations of neuronal somata in the sphenopalatine ganglion. The present study provides the direct evidence supporting the notion that nitric oxide is richly produced in autonomic nerves of the nasal mucosa derived from the sphenopalatine ganglion.

Animals↗
PubMed1995

[Relationship between intraoperative pleural lavage cytology and recurrence in pleural cavity after resection of lung metastasis from colorectal cancer].

Seventeen patients with lung metastases from colorectal cancer underwent intraoperative pleural lavage cytology immediately after thoracotomy from August 1988 to December 1994. Patients with pleural effusion and/or dissemination were excluded. The median followup period was 34 months (range 3-52 months). Of the 17 patients, 13 were cytologically negative (76%, group A) and 4 were positive (24% group B). Recurrence rate in the pleural cavity was 25% (1/4) in group B and 0% (0/13) in group A. The three-year survival rate was 0% in group B and 78% in group A, respectively. These results indicate that intraoperative pleural lavage cytology is useful in the assessment of prognosis, and locoregional therapy should be considered for cytology positive group.

Colorectal Neoplasms↗
PubMed1995

[Important prognostic factors in surgically treated gastric cancer patients].

In order to clarify important factors in prognosis of patients with gastric cancer, 3,515 surgically treated cases were investigated. The survival rate varied widely depending on the curativity which strongly correlated with the stage of the disease. For example, such cases with peritoneal dissemination and hepatic metastasis have a poor prognosis. According to our multivariate investigation by Cox's proportional hazard model (SAS, PHREG procedure) based on resectable cases of gastric cancer, the most significant prognostic factor was lymph node metastasis with a ratio of risk 4.58, followed by the macroscopic-type cancer, ratio of risk 3.61, and depth of invasion, with the ratio of risk 2.22. It should be noted that such factors as macroscopic type of cancer turned out to be an important prognostic factor aside from those related with the stage of cancer, such as lymph node metastasis and depth of invasion. Type 4 gastric cancer had a markedly poor prognosis. Among all surgically treated patients, the histologic type was insignificant as a prognostic factor, however, when limited to mucosal cancer, the undifferentiated type had a higher lymph node metastasis rate than the differentiated type. This result suggests that the histologic type of cancer should be carefully considered in case of endoscopic treatment of gastric cancer.

Analysis of Variance↗
PubMed1995

Expression and role of ionotropic glutamate receptors in pancreatic islet cells.

Although the excitatory amino acid glutamate and its receptors play crucial roles in many functions of the central nervous system (CNS), their presence in the peripheral tissues has remained unclear. In the present study, we have identified kainate, alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA), and N-methyl-D-aspartate (NMDA) receptor subtype mRNAs in pancreatic islets, using reverse transcriptase polymerase chain reaction (RT-PCR). Intracellular calcium ([Ca2+]i) measurements and electrophysiological recordings indicate that kainate, AMPA, and NMDA all elicit increases of [Ca2+]i in single pancreatic beta-cells and depolarize them. In addition, kainate and AMPA stimulate insulin secretion from isolated pancreatic islets, whereas NMDA does not. Also, immunocytochemical study shows the presence of intense glutaminase immunoreactivity in pancreatic alpha-cells and intrapancreatic ganglia, a finding compatible with the possibility that glutamate is released from alpha-cells as well as from neurons. Because the inhibitory amino acid gamma-amino butyric acid (GABA) is present in beta-cells as well as in neurons and inhibits glucagon secretion from alpha-cells, the present study suggests that glutamate and GABA are coordinated in the regulation of hormone secretion in pancreatic islets.

Animals↗
PubMed1995

[A case of occult cancer of pancreas which was appropriately resected by intra operative cytodiagnosis using a balloon catheter].

A new method of intraoperative cytodiagnosis was performed for one patient with occult neoplasms of the pancreas in order to locate the original site of cancer cells, using a balloon catheter. Cancer cells were detected in the pancreatic juice obtained from the pancreatic body only. The pancreatic body was removed, and the tail of the pancreas was anastomosed to the stomach. The post operative course was good without diabetes, and it was confirmed histologically that minimally invasive adenocarcinoma existed in the pancreatic body. Thus this procedure is beneficial because it can preserve as much pancreatic function as possible without losing the chance of cure by surgery.

Adenocarcinoma↗
PubMed1995

[Health personnel staffing requirements for health examination for the age of 1 1/2 in municipalities in Japan].

Municipalities in Japan offer health education, health counseling, health examination, and home visit services for each development stage of children and for their mothers. In order to determine personnel staffing requirements for the health examination for the age of 1 1/2 as of 1989, data from a questionnaire survey in 1990 conducted by the Ministry of Health and Welfare, was analyzed. Questionnaires were sent to all municipalities and there were 3,198 responses for the response rate of 97.9%. Results showed that in 1989, 98.9% of the 3,012 municipalities were able to independently perform health examinations for 1 and half year old, and in only 0.9% these examination were performed by clinical hospitals. In the large cities designated by the Government, the health personnel system adequately supported these health examination. However due to lack of health personnel, rural towns and villages with small populations required public health nurses to be assisted by other staff, such as health workers or volunteers. And particularly they required help by public health nurses from prefectural Health Centers. For example, in those areas with populations less than 3,000, 53% of the total volume of the work required to be performed by public health nurses during the health examination had to be covered by assistance from prefectural public health nurses. While in cities with more than 300,000 population large numbers of health personnel were assigned to examinations of children, the large number of children processed resulted in inadequate time for each child/mother pair. Further study of quality levels of the examinations need to be performed.

Child Health Services↗
PubMed1994

Is the long-term survival rate improved by preoperative irradiation prior to Whipple's procedure for adenocarcinoma of the pancreatic head?

OBJECTIVE: To determine whether or not both regional control and long-term survival rate were improved by preoperative irradiation prior to curative pancreatectomy for adenocarcinoma of the pancreatic head. DESIGN: Retrospective study of recorded medical data from 1985 to 1989. SETTING: The Center for Adult Diseases, Osaka, one of the major cancer centers in Japan. PATIENTS AND INTERVENTION: Fifty-four consecutive patients in whom pancreatic head cancer had been judged to be resectable by preoperative diagnostic techniques. A total of 50 Gy per 10 MeV of x-ray was irradiated preoperatively to the wide field, including the pancreatic head area, in 23 patients (group A) but not in the 31 remaining patients (group B). The background factors before treatment did not differ between these two groups. OUTCOME MEASURES: Resectability, postoperative survival, and modes of cancer recurrence. RESULTS: At laparotomy, curative pancreatectomy was possible in 17 patients (74%) in group A and 19 (61%) in group B (not significant). In patients undergoing resection, the 1-year survival rate was 75% in group A and 43% in group B (P < .05). However, 3- and 5-year survival rates were almost the same in both groups (28% vs 32% and 22% vs 26%, respectively). With regard to the cause of death after pancreatectomy, group A had a significantly lower incidence of deaths due to regional recurrence within 1.5 postoperative years compared with group B, whereas deaths due to hepatic metastasis were markedly higher after 1 postoperative year in group A compared with group B. CONCLUSIONS: Preoperative irradiation prior to pancreatectomy succeeded in reducing the incidence of early deaths due to regional recurrence. However, owing to the next barrier--death due to hepatic metastasis after 1 postoperative year--long-term (3- and 5-year) survival rate was not improved at all.

Adenocarcinoma↗
PubMed1994

Gastric cancer in young adults: growth accelerating effect of pregnancy and delivery.

The relationship between pregnancy and/or delivery (p&d) and the stage of gastric cancer was studied in 64 female and 57 male patients aged 34 or younger with gastric cancer. Gastric cancer diagnosed within 2 years after p&d (group A, 20 patients) was more progressive (unresectable in 20%) than those of the other young female patients with children (group B, 24 patients; 5%) or without children (group C, 20; 0%), or young male patients (group D, 57; 3%) (P < 0.05). The 5-year survival rate in group A (60.0%) was lower than in group B (83.3%) and group C (85.0%) (P < 0.05 between groups A and B). There were no differences in the duration from the onset of subjective symptoms to diagnosis in the four groups. Out of eight patients who were pregnant after gastrectomy for stomach cancer, one died from recurrence immediately after abortion. These results suggest that pregnancy and/or delivery in young females accelerates the growth of stomach cancer.

Adult↗
PubMed1994

Morphological analysis of acute ulcerative colitis experimentally induced by dextran sulfate sodium in the guinea pig: some possible mechanisms of cecal ulceration.

This study in the guinea pig demonstrated that ulcerative colitis-like lesions were induced more rapidly and effectively than in other laboratory animals by the oral administration of dextran sulfate sodium (DSS). In all guinea pigs receiving 3% DSS solution, diarrhea was noted within 48h, and bleeding at 48-72h. Light microscopically, hemorrhagic and ulcerative lesions were observed in the cecum and proximal colon as early as 72h after administration. Lamina propria macrophages, gather in the subepithelial region under normal conditions, were markedly increased in number after DSS administration; by 96 h, they were approximately three times as many as in the control specimens. The cecal mucosa was also characterized, in earlier stages, by the obliteration of virtually all cryptal lumina because of the accumulation of mucous secretions, leading to the subsequent disappearance of the crypts. The obliteration of crypts, which preceded the increase of macrophages, is suggested to play a leading part in this ulceration.

Acute Disease↗
PubMed1994

Production of endothelin-1 and thrombomodulin by human pancreatic cancer cells.

Analysis of bioactive substances produced by cancer cells is one approach to understanding the biological features of human cancer. One of these bioactive substances is endothelin (ET)-1, a peptide with potent vasoconstrictive activity produced by vascular endothelial cells. We have previously reported the production of ET-1 by several types of human cancer, especially pancreatic cancer cells. To elucidate whether these cancer cells might share biological characteristics with vascular endothelial cells, we investigated the production of three ET isoforms in pancreatic cancer cells, using a specific radioimmunoassay. Further, we also investigated whether these cells produce thrombomodulin (TM), another product of endothelial cells functioning as a modulator of procoagulant activity. ET-1 was detected in 11 of 12 pancreatic cancer cell lines (92%) while ET-2 and ET-3 were detectable in only one cell line. Gel filtration analysis confirmed the presence of ET-1. Moreover, TM was detected in the cell lysates of 11 of the 12 cell lines (92%) and it was released into the culture medium in the majority (58%) of these cell lines. TM mRNA was also detected in these cells. In addition, TM was demonstrated immunocytochemically along the cell surface. These results suggest that pancreatic cancer cells share two characteristics with endothelial cells: the production of ET-1 and TM.

Antibodies, Monoclonal↗
PubMed1994

Preparation of 6(1),6n-di-O-(tert-butyldimethylsilyl)-cyclomalto-octaoses.

Four positional isomers of 6(1),6n-di-O-(tert-butyldimethylsilyl)- cyclomalto-octaose (n = 2-5) were prepared by reaction of cyclomalto-octaose (1, cG8) with tert-butyldimethylsilyl chloride in pyridine, and were isolated by high-performance liquid chromatography. The regiochemical determination of those positional isomers was performed by comparison with authentic compounds, prepared from 6(1),6n-di-O-trityl-cG8s (n = 2-5).

Carbohydrate Sequence↗
PubMed1994

Morphological analysis of multinucleated giant cells occurred in experimental autoimmune myocarditis.

Our previous study reported the rich existence of multinucleated giant cells in an autoimmune myocarditis experimentally induced in rats. The present study investigated the histochemical and ultrastructural characteristics of these giant cells. Histochemistry for an acid phosphatase clearly demonstrated multinucleated giant cells dispersed at the inflammatory foci. Ultrastructurally, the giant cells were shown to be single cells, but not clustered cells. Their ultrastructural characteristics were very similar to the basic features of macrophages, except that the giant cells were poor in lysosomes and phagosomes. It was noticeable that some macrophages possessed three or more nuclei, displaying an intermediate form between mononuclear macrophages and multinucleated giant cells. These findings suggest that the giant cell in the experimental autoimmune myocarditis is a single multinucleated cell, and possibly derived from macrophages by cell-to-cell fusion.

Acid Phosphatase↗
PubMed1994

Lamina propria macrophages involved in cell death (apoptosis) of enterocytes in the small intestine of rats.

In the rat small intestine, apoptotic enterocytes are exfoliated at the villus tip as a whole cell, in contrast to guinea pig enterocytes which are phagocytosed by macrophages in their cell body and shed off only in their apical cortex. While macrophages gather in the lamina propria of the intestinal villi in both species, their functions seem to differ. Unlike the guinea pig, lamina propria macrophages observed in the rat small intestine did not show morphological signs of phagocytosis, revealing few cellular elements in their phagosomes. At the "shoulder" of the villus, i.e., a certain distance proximal to the villus tip, subepithelial macrophages extended a thick process deep into the epithelium; their branched terminals penetrated the cytoplasm of enterocytes, resulting in the formation of excavated spaces in the cell body. Processes of macrophages frequently reached close to the brush border. At the shoulder of the villus, a few effete cells showed typical apoptotic signs and appeared to be pushed out into the lumen; still, the shedding of apoptotic enterocytes was recognized mainly at the very top of the villus, where no intraepithelial processes of macrophages could be seen. The present findings indicate that in the rat, lamina propria macrophages do not engulf aged enterocytes, but are involved in inducing their apoptosis.

Acid Phosphatase↗
PubMed1994

[Exertional hypoxemia evaluated by pulse oximetry in patients with interstitial lung diseases].

The pattern of change in arterial oxyhemoglobin saturation (SpO2) measured by pulse oximetry (PO) during exercise, including daily activities, was studied in 23 patients with interstitial lung disease (ILD), 19 of whom had idiopathic pulmonary fibrosis, 3 collagen vascular disease, and 1 BOOP. Hypoxemia, as detected by PO appeared without dyspnea at the beginning of exertion or at a mild workload. Exercise usually induced significant changes in the same fashion first in heart rate, then in SpO2, and then in dyspnea, but stair climbing had a different pattern. Workload at the lactate threshold (LT) and symptom-limited maximal exercise (SL) in a bicyclergometer incremental exercise test correlated well with distance walked in a 10-minute walking test (10-eMD) (p < 0.01). Similarly, the degree in desaturation in each exercise test was closely correlated (p < 0.01). Exertional hypoxemia was more prominent in patients with ILD than in those with chronic pulmonary emphysema. Nevertheless, dyspne changed less per change in SpO2 in ILD patients. We conclude that prolonged monitoring of SpO2 by PO will disclose the presence of exertional desaturation in ILD patients.

Activities of Daily Living↗
PubMed1994

[Personnel requirements for health examination of infants under 5 months in municipalities in Japan].

Municipalities offer health education, health counseling, health examinations, and home visitation service for infants and their mothers. In order to determine what the personnel staffing requirements were for health examination of infants under 5 months for municipalities in Japan in 1989, a questionnaire survey was conducted in 1990. Questionnaires were sent to all municipalities and 3,198 responses were received for a response rate of 97.9%. Responses from 912 municipalities were considered invalid, leaving a total of 2,286 responses that were analysed. Results showed that 79.2% of the 2,286 municipalities were able to perform health examinations for infants under 5 months independently, while in 6.5% of the municipalities these examinations were performed by the clinical hospitals. Analysis by size of municipalities showed that 85.7% of the cities with populations of 500,000 or more were able to perform health examinations independently. In the large cities designated by the Government, the health personnel system adequately supported these health examinations. However in rural towns and villages with small populations, it was necessary for public health nurses to be assisted by other staff, most of whom were public health nurses from prefectural health centers. For example, in areas with populations of less than 3,000, about 60% of the total volume of the work required to be performed by public health nurses during the health examinations had to be covered by assistance from prefectural public health nurses.

Child Welfare↗