Biomedical subjects

S Kamata

Publications and source records attributed to S Kamata.

260 records · Page 15Linked to original sources

PubMedDate not supplied

Adhesive mucous gel layer and mucus release as intestinal barrier in rats.

BACKGROUND: Although it has been reported that total parenteral nutrition induces an increased intestinal permeability and a decreased mucous gel layer covering the intestinal epithelium, the role of mucous gel on intestinal permeability has not been well understood. We examined the in vivo effects of N-acetyl cysteine (NAC) as mucolytic agent and colchicine as suppressant of the mucus production on the intestinal transmission of fluorescein isothiocyanate dextran 70,000 (FITC-dextran). METHODS: Rats were divided into four groups. In each group, FITC-dextran (750 mg/kg) with or without NAC (3000 mg/kg) was injected into the small intestinal lumen 3 hours after intraperitoneal injection of saline or colchicine (Col, 10 mg/kg). Thirty minutes after injection of FITC-dextran, blood samples were taken from portal vein to analyze plasma fluorescein concentration by fluorescence spectrometry. Samples of small intestine were sectioned in a cryostat for fluorescence microscopy, and the identical sections were stained by periodic acid-Schiff reaction. RESULTS: Plasma FITC-dextran level in NAC group was higher than that in control group (p < .01), that in Col + NAC group was higher than that in Col group (p < .01) and that in Col + NAC group was higher than that in NAC group (p < .05). The spaces between villi were filled with mucous gel in the control and Col groups, whereas those were not entirely filled with mucous gel in NAC and Col + NAC groups. FITC-dextran and mucous gel showed complementary distribution in all rats. The villous interstitial edema was recognized in NAC group and the villi were disrupted in Col + NAC group. CONCLUSIONS: These results suggest that intestinal permeability is possibly affected not only by the mucous gel covering the intestinal epithelium but also by mucus release from goblet cells of the small intestine.

Acetylcysteine↗

PubMedDate not supplied

Developmental changes in distribution of the mucous gel layer and intestinal permeability in rat small intestine.

BACKGROUND: From the developmental aspects, the distribution of fluorescein isothiocyanate dextran 70,000 (FTTC-dextran) and mucous gel across the lumen of small intestine was observed as an investigation into the role of mucous gel on intestinal permeability. Furthermore, the effect of N-acetyl cysteine (NAC), a mucolytic agent, on intestinal permeability was examined. METHODS: In suckling and weaned rats, FTTC-dextran (750 mg/kg body wt) was gavage-fed. After 3 hours, blood samples were taken by cardiac puncture to analyze plasma FTTC-dextran by fluorescence spectrometry. Samples of small intestine with luminal contents were frozen and sectioned in a cryostat for fluorescence microscopy; the same sections were placed in a 0.2% celloidin solution to preserve mucous gel and were stained by periodic acid-Schiff reaction for light microscopy. In weaned rats, intestinal permeability was examined with different concentrations of intraluminally instilled NAC. RESULTS: The plasma level of FTTC-dextran showed a significant increase (p < .01) in suckling rats compared with the weaned rats. Morphologic findings were similar in both the jejunum and ileum: The spaces between villi were not entirely filled with mucus but filled with FTTC-dextran in suckling rats, whereas the spaces were filled with mucus and not filled with FTTC-dextran in weaned rats. Intestinal permeability in groups with NAC were significantly higher (p < .01) than that in group without NAC. CONCLUSIONS: These results suggest that an increase in the mucous gel layer that coats the epithelial lining according to the maturation of the gastrointestinal tract is one of the most important factors for a restriction in intestinal permeability.

Acetylcysteine↗

PubMedDate not supplied

Total parenteral nutrition increases uptake of latex beads by Peyer's patches.

BACKGROUND: Dysfunction of the intestinal barrier, as evidenced by increased intestinal permeability and bacterial translocation, has been reported under total parenteral nutrition (TPN). However, the role of Peyer's patches on the intestinal barrier in TPN is not well understood. We investigated whether TPN alters the uptake of microparticles by the follicle-associated epithelium of Peyer's patches. METHODS: Twenty rats were divided into two groups, a control group and a TPN group. Fluorescent polystyrene latex beads, 3.2 +/- 0.2 microns in diameter, were used as a probe for measuring the uptake by Peyer's patches. After 1 week of consuming either the control or TPN diet, rats were killed. On the day of killing, 0.1 mL of latex beads solution was injected into a 1-cm length of ileal loop, within 10 cm of the ileocecal valve. Samples were taken after 30 minutes of injection, sectioned by cryostat, and then viewed under a fluorescent microscope. Follicle-associated epithelial length and particles were counted using a confocal laser scanning microscope. The number of particles within each compartment was standardized per unit length of epithelium of Peyer's patches. RESULTS: Particle numbers within Peyer's patch dome of the TPN group were significantly increased compared with those of the control group (p < .01). CONCLUSIONS: These data suggest that dysfunction of the intestinal barrier in TPN might be associated with a change of uptake by Peyer's patches.

Animals↗

PubMedDate not supplied

Insulin-like growth factor-1 modulation of intestinal epithelial cell restitution.

After superficial intestinal injury, the mucosal integrity is reestablished by rapid migration of epithelial cells from the adjacent area in a process called restitution. Our previous study suggested that growth hormone improves intestinal healing in an experimental small bowel ulceration, mediated by insulin-like growth factor-1 (IGF-1). The aim of the present study was to assess the role of IGF-1 in mucosal epithelial restitution using an in vitro epithelial wound model. Wounds were established in confluent monolayers of the intestinal cell line, IEC-6. Migration was quantitated in the presence or absence of IGF-1 as the number of cells migrating across the wound edge. Proliferation was assessed by thymidine incorporation. IGF-1-enhanced epithelial cell migration by 2- to 2.5-fold after 12- and 24-hour treatment, respectively, the first step involved in gastrointestinal wound healing. Cell proliferation was significantly stimulated by IGF-1 as well. In addition, expression of transforming growth factor-beta (TGF-beta) mRNA was significantly enhanced in the wounded monolayers treated with IGF-1. IGF-1 receptor mRNA was found to be detectable throughout the gastrointestinal mucosa and in the intestinal epithelial cells. In conclusion, these findings suggest that IGF-1 plays an important role in reconstitution of intestinal epithelial integrity after mucosal injury.

Animals↗

PubMedDate not supplied

Operative morbidity and mortality after D2 and D4 extended dissection for advanced gastric cancer: a prospective randomized trial conducted by Asian surgeons.

BACKGROUND/AIMS: A randomized study was performed to evaluate morbidity and mortality after D2 (level 1 and 2 lymphadenectomy) and D4 (D2 plus lymphadenectomy of para-aortic lymph nodes) dissection for advanced gastric cancer. METHODOLOGY: Two hundred and fifty-six patients with advanced gastric adenocarcinoma were enrolled (128 to each group). Patients were randomly allocated into D2 (N = 128) or D4 (N = 128) group. The first and second tiers of lymph nodes are removed in D2 dissection. In D4 gastrectomy, the paraaortic lymph nodes were additionally removed. RESULTS: There was no indication of significant distribution bias with regard to age, sex, T-grade, and N-grade between the two groups. Operation time of D4 gastrectomy (369 +/- 120 min) was significantly longer than that of D2 gastrectomy (273 +/- 1103 min), and blood loss of the D4 group (872 +/- 683 mL) was significantly greater than that of the D2 group 571 +/- 527 mL (P < 0.001). Five (4%) and two (2%) medical complications developed in the D2 and D4 groups, respectively. Surgical complications developed in 28 (22%) and 48 patients (38%) after D2 and D4 gastrectomy. The most common complications were anastomotic leakage, pancreatic fistula, and abdominal abscess. Pancreatic fistula developed in 6 (19%) of 32 patients after D4 plus pancreatosplenectomy, but the incidence of pancreatic fistula after D2 gastrectomy plus pancreatosplenectomy was low (6%, 1/16). Two patients died within 30 days of operation (0.8%, 2/256), and each patient belonged to the D2 and D4 group. CONCLUSIONS: Although there is a significantly higher surgical complication rate in D4 dissection, D4 dissection can be done safely as D2 dissection when performed by well-trained surgeons.

Abdominal Abscess↗

PubMedDate not supplied

Use of lung-thorax transverse area ratio in the antenatal evaluation of lung hypoplasia in congenital diaphragmatic hernia.

For evaluation of lung hypoplasia in congenital diaphragmatic hernia (CDH), we measured lung-thorax transverse area ratio (LT ratio), which was defined as the area of bilateral lung profiles divided by the profile area of thorax at the level of the four-chamber view of the heart, using fetal ultrasonography. LT ratio in cases with CDH was lower than that in the control group and related well to the postnatal respiratory condition. Measurement of LT ratio using fetal ultrasonography may be useful in predicting the degree of lung hypoplasia in fetuses with CDH.

Female↗

PubMedDate not supplied

Surgical experience with traumatic rupture of the thoracic aorta.

Nine cases of traumatic thoracic aortic rupture (TAR), operated on at St. Marianna University Hospital between July 1980 and December 1988, were reviewed in order to evaluate the role of contrast-enhanced CT in the early diagnosis of TAR. The absence of mediastinal hematoma on CT eliminated the need for aortography in 30 (38.5%) of the 78 patients suspected of having TAR on the basis of chest roentgenograms. The presence of mediastinal hematoma necessitated aortography in 48 patients. However, operative treatment was carried out without aortography in 3 patients who had specific signs of rupture on CT. CT proved to be a reliable indicator for the selection of the patients who need aortography. As a rule, emergency operations were performed in these patients. Simple aortic crossclamping was employed in 4 patients, and heparinless left heart bypass with the BioPump was performed for spinal cord protection in 2 recent patients without complication of embolization. Use of the BioPump as an adjunct in the repair of TAR appears to be promising.

Accidental Falls↗

PubMedDate not supplied

Vitamin D metabolism in biliary atresia: intestinal absorptions of 25-hydroxyvitamin D3 and 1,25-dihydroxyvitamin D3.

In children with biliary atresia, defective intestinal absorption of vitamin D and impaired hepatic uptake and 25-hydroxylation of vitamin D lead to a deficiency of vitamin D and rickets. We recently observed severe rickets in a 3-year-old boy with corrected biliary atresia resulting in jaundice, despite oral treatment with 1 alpha-hydroxyvitamin D3 (1 alpha-OHD3) or 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3]. He had low 25-hydroxyvitamin D (25-OHD) and high 1,25-(OH)2D serum levels. Intramuscular vitamin D2 administration produced radiological and biochemical evidence of recovery. Oral 1,25-(OH)2D3 (0.1 microgram/kg) and 25-OHD3 (10 micrograms/kg) tolerance tests were done to assess the ability to absorb vitamin D and the effectiveness of using these drugs orally. Eleven children with corrected biliary atresia, aged 9 months to 7 years, were studied. In oral 1,25-(OH)2D3 tolerance tests, the increments above the baseline serum levels of 1,25-(OH)2D were 140.7 +/- 27.4 pg/ml in nonjaundiced patients (n = 5). In jaundiced patients (n = 3), 1,25-(OH)2D3 absorption in two patients with high basal 1,25-(OH)2D values was lower than that of nonjaundiced patients; however, the absorption in the third patient with a low basal value was similar to that of nonjaundiced patients. In oral 25-OHD3 tolerance tests, the mean increase of serum 25-OHD was 48.9 +/- 30.6 ng/ml in nonjaundiced patients (n = 5) and 23.7 +/- 9.5 ng/ml in jaundiced patients (n = 4), the peak serum 25-OHD levels being reached 6-12 h after 25-OHD3 loading.(ABSTRACT TRUNCATED AT 250 WORDS)

Biliary Atresia↗