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Biomedical subjects

B Zederfeldt

Publications and source records attributed to B Zederfeldt.

At least 73 records · Page 4Linked to original sources
PubMed1985

Comparison of healing in the left colon and ileum. Changes in collagen content and collagen synthesis in the intestinal wall after ileal and colonic anastomoses in the rat.

Collagen metabolism was compared after anastomosis in the small and large intestine of rats. Animals were sacrificed 2 and 4 days postoperatively, when three standardized biopsy specimens were taken on either side of the anastomosis. In one group of rats, anastomosis was performed in both ileum and colon and 3H L-proline was given 24 hours before sacrifice, for studies of collagen synthesis. Animal weight, specimen dry weight, collagen concentration, collagen content per standardized biopsy, specific activity of collagen and total radioactivity were measured. Weight loss was greater after colon than after ileum anastomosis, indicating that the rats were more severely affected by colon surgery than by comparable operations on the ileum. Collagen content increased earlier and more in large intestinal than in small intestinal wall. The earlier activation of collagen synthesis in colon may have been related to differences in intestinal contents (e.g. bulk or bacteria).

Animals↗
PubMed1985

Healing of ileocolic anastomoses. Breaking strength and collagen content in the intestinal wall after ileocolic resection and anastomosis in the rat.

Breaking strength, collagen concentration and collagen content of the intestinal wall were studied in rats after ileocolic anastomosis. The values were compared with findings in control rats without operation and in previous studies of ileal and colonic anastomosis. Collagen content and concentration in the ileal wall were lower on the third day of healing than previously found during ileal healing. Breaking strength decreased in the early phase to the same extent as in previous experiments, but the restoration of strength from the third day on was more rapid than previously noted in ileal anastomoses. The changes observed in the ileum following ileocolic anastomosis were more like the pattern in colon. It is suggested that intestinal content (bacteria and intraluminal bulk) influences the collagen metabolism in the intestinal wall.

Animals↗
PubMed1984

The effect of relative bowel rest on collagen metabolism and suture holding capacity in the colonic wall. Studies in the rat.

In a previous experimental study it was shown that bowel rest with low residue diet led to a reduction of the non-collagenous substances in the intact, unoperated colon, while the collagen content remained unchanged. In the cecum, both the collagen content and the non-collagenous substances were markedly increased. In the present investigation the effect of relative bowel rest on collagen synthesis in the colonic wall was studied. Further, a possible influence on mechanical properties was evaluated. It was found out that bowel rest led to a marked decrease of collagen and protein synthesis in the colon. In the cecum, there was an unchanged collagen synthesis but an increased protein synthesis. It can be deduced that lysis of collagen is decreased in all parts of the colon. The depression of collagen turnover in the colonic wall was not accompanied by measurable changes in mechanical strength. It remains to be studied whether the observed changes in collagen metabolism do affect colonic healing.

Animals↗
PubMed1984

The effect of relative bowel rest on collagen in the colonic wall. Studies in the rat.

In previous studies it was shown that diminished colonic content pre- and postoperatively, obtained by feeding rats low residue diet, results in less marked postoperative disturbances in collagen metabolism than in animals fed standard laboratory diet. In the present investigation the effect of relative bowel rest on collagen content and collagen concentration in the intact colonic wall was studied by feeding unoperated rats low residue diet. It was found that the colonic and cecal contents were reduced significantly and that this primarily affected the non-collagenous substances in the colon with a marked decrease, while the collagen content was unchanged. In the cecum, both the collagen and the non-collagenous contents were significantly increased. Thus, the pattern of change in biochemical response varied in different parts of the large intestine after institution of bowel rest. Further, the present data imply that collagen concentration can be misleading as a measure of the actual collagen amount.

Animals↗
PubMed1984

The effect of relative bowel rest on healing of colonic anastomoses. Breaking strength and collagen in the colonic wall following left colon resection and anastomosis in the rat.

The breaking strength of anastomoses in the left colon in the early phase of healing was studied in rats fed low residue diet (Biosorbin MCT) and the results were compared to those from rats fed standard laboratory diet. Further, eventual correlation between mechanical strength development and collagen content in the colonic wall around the anastomosis was evaluated. The anastomotic strength with sutures in place decreased by approximately 30% of the immediate postoperative value during the first two days in both groups of animals. There was no correlation between changes in anastomotic strength and collagen content at that time. After the second day there was a gradual increase of anastomotic strength, reaching the strength at day 0 after 7 days. The regain of strength was mainly due to collagen deposition in the anastomosis. Despite more collagen deposition in animals on standard laboratory diet the anastomoses had comparable strength development in the two groups. It was concluded that low residue diet does not impair the suture holding capacity or the anastomotic strength. Instead there was some evidence for a more uncomplicated healing when the bowel content was diminished.

Animals↗
PubMed1984

The effect of relative bowel rest on healing of colonic anastomoses. Collagen synthesis and content in the colonic wall after left colon resection and anastomosis in the rat.

Collagen metabolism was studied in the colonic wall of rats after standardized resection and anastomosis. Diminished faecal loading was obtained by feeding rats low-residue diet (Bisorbin MCT). The postoperative increase of collagen synthesis and collagen content was on a lower level in these rats than in rats on standard laboratory diet. The increase was confined to the immediate anastomotic region and presumably represented changes in collagen caused by the operative trauma per se. It was concluded that the intraluminal content is an important factor in stimulating collagen turnover. The findings of lower collagen turnover in the anastomotic area in animals on low-residue diet may have positive significance, but could also imply impairment of healing. For elucidation of this question, studies on mechanical strength of the anastomosis are necessary.

Animals↗
PubMed1983

Breaking strength of small intestinal anastomoses.

The breaking strength of standardized small bowel anastomoses at different times after surgery was studied in the rat. The anastomotic strength with sutures in place successively decreased during the first 3 postoperative days to approximately 15 percent of the immediate postoperative value. This indicates a rapid decrease in the suture holding capacity of the gut wall in the early postoperative course. From the fourth day onward a rapid increase in strength was recorded. This could be due not only to deposition of collagen in the tissue bridging the anastomosis but also to the regained capacity of the gut wall to withstand tearing forces. After 14 days the strength of the anastomosis was due mainly to healing, and the relative contribution from the sutures was negligible. It may be that tearing of sutures through the tissue is more important than defective healing for anastomotic complications.

Animals↗
PubMed1982

Acute abdomen in the surgical emergency room. Who is taken care of when for what?

During 1977, 5279 male and 4616 female visits (9895 in all) for acute abdominal conditions were made to the emergency room at the Department of Surgery in Malmö, Sweden. Twice as many patients were seen on Mondays and Tuesdays as on Saturdays. More than 50% of the visits were classified as non-specific abdominal pain or gastritis. The highest incidence of these two conditions was found in the 20-29-year age group and 2-3 times as many patients in this age group were seen on Mondays as on Saturdays and Sundays. It is concluded that studies on the age- and sex-specific incidence rates of different abdominal disorders should be of great value for proper planning of diagnostic and therapeutic resources and further of importance for the planning of the education and training of the general surgeon. Differences in the age- and sex-specific incidence rates as well as differences in the incidence rates from one time period to another illustrate the value of retrospective studies as a basis for future prospective studies regarding cause and potential for prevention of acute abdominal diseases.

Abdomen, Acute↗
PubMed1981

Influence of zinc on synthesis and the accumulation of collagen in early granulation tissue.

Chronic zinc deficiency causes a delay of reparative processes. The rate of repair is normalized by the administration of zinc. An acute lowering of the serum zinc level follows trauma. In a previous experimental study, it was demonstrated that the intramuscular administration of zinc beginning before trauma results in an increased collagen accumulation in early granulation tissue. In this study, the rate of collagen synthesis was determined to see if the higher amount of collagen found in early granulation tissue could be explained by increased collagen synthesis. The rate of collagen synthesis was studied by the determination of the incorporation of 14C-L-proline into collagen in vivo and in vitro. No difference was found regarding collagen synthesis in the granulation tissue of rats in the control and zinc treated groups. Specific activity of collagen, a measure of newly synthesized collagen in relation to the total amount of collagen, was found to increase markedly during the observation time. Further, the specific activity was found to be lower in the rats of the zinc treated groups than in the rats of the control groups on days 4 and 5, an indication that, after the administration of zinc there is more earlier synthesized, not labeled, collagen present. A possible explanation is that there is a concomitant synthesis and breakdown of collagen in granulation tissue and that the rate of breakdown is decreased by the administration of zinc.

Animals↗
PubMed1980

Granulation tissue formation in zinc-treated rats.

Chronic zinc deficiency impairs would healing. It is not known if acute decrease of werum zinc ocdurring after trauma has the same negative effect. We have studied the effect of extra zinc supply in connection with trauma on granulation tissue formation in subcutaneously implanted polyvinyl sponges. Zinc given postoperatively had no effect on granulation tissue formation. Zinc administered also preoperatively resulted in higher amount of collagen by the fourth postoperative day but not later. This effect of zinc on the collagen content can be explained either by an increased collagen synthesis or by decreased collagen break down. The fact that zinc had no effect when given only postoperatively indicates that collagen synthesis is not affected. The demonstrated effect of zinc thus seems to be due to decreased collagen break down.

Animals↗
PubMed1980

Collagen synthesis in granulation tissue formed in rats treated with female sex hormones.

In previous studies, we have shown that female sex hormones given in dosages corresponding to plasma levels in the last trimester of pregnancy retard collagen accumulation in early phases of experimental granulation tissue formation. Results of incorporation experiments using radioactive proline reported in this article indicate that this hormone treatment reduces general protein synthesis in granulation tissue and, even more markedly, the synthesis of collagen. Since collagen accumulation into granulomas is normal in the later phases of healing, it is suggested that hormone treatment not only decreases synthesis of collagen but also decreases breakdown of collagen. Hormone treatment did not affect the solubility of labeled collagen. No differences were observed in the synthesis of different collagen types. Under conditions when active collagen and protein synthesis occurs in the uterus and fetus, corresponding synthesis in other tissues is, thus, decreased. This may serve as an energy and protein saving function during pregnancy. The results may have applications for treatment of extensive scar formation.

Animals↗
PubMed1980

Cytochemical study of granulation tissue in zinc treated rats.

The effect of zinc administration on cell composition of early granulation tissue has been studied in rats using histological and cytochemical methods. Granulation tissue was obtained by subcutaneous implantation of polyvinyl sponges. The experimental group was given zinc intramuscularly daily beginning preoperatively. Zinc administration does not change the early inflammatory cell infiltration but results in a more rapid disappearance of polymorphonuclear granulocytes from the granulation tissue. No effect can be seen on the mononuclear cell population. The observations are related to alterations in repair processes following zinc administration.

Acid Phosphatase↗