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S Renvall

Publications and source records attributed to S Renvall.

34 records · Page 2Linked to original sources
PubMed1981

Collagen synthesis in cells cultured from v. Recklinghausen's neurofibromatosis.

Subcutaneous tumors of a patient with v. Recklinghausen's neurofibromatosis contained about 31% collagen calculated on the basis of lipid-free dry weight. Slices of the tumors synthesized collagen at a rate (4.7-8.5% from total protein) which was higher than that of the skin slices (2.8-5.9%). Neurofibromatosis cells were cultured from tumors of two patients. They synthesized relatively much more collagen than cultures of skin fibroblasts of the same patient or of healthy age-matched control persons. The second patient's cultures were studied in detail. The cell densities of these cultures were higher and expressed more variation than the densities of control skin fibroblasts. Ion exchange cellulose chromatograms, SDS-polyacrylamide gel electrophoresis and 3-hydroxyproline analysis of the radioactive proteins made by the cultures indicate that most of the collagenous proteins resembled type I collagen. High proliferative capacity and high collagen synthesis of selected neurofibromatosis cells explains the growth of solid tumors.

Cells, Cultured↗
PubMed1981

Collagen synthesis in cultured mesothelial cells. Response to silica.

Mesothelial cells were isolated from the peritoneal surface of rats using trypsinization. The cells were polygonal-shaped and proliferated rapidly forming confluent cultures. Application of colloidal silica to mesothelial cell cultures in doses known to induce peritoneal adhesion disease was injurious to the cells and reduced their synthesis of total proteins and collagen. This effect was dose dependent. Media from silica-treated mesothelial cells and granulation tissue fibroblasts were applied to similar but non-treated mesothelial cell and granulation tissue fibroblast cultures. Media from SiO2-treated mesothelial cells increased collagen synthesis markedly both in the mesothelial cell and fibroblast cultures compared with the control cultures as estimated from the incorporation of radioactive proline into hydroxy-proline-containing proteins. However, no stimulation of collagen synthesis was induced by media from the SiO2-treated granulation tissue fibroblasts. Similar effects are known to be induced in fibroblast cultured by media from silica-treated peritoneal macrophage cultures. The alkaline ribonuclease activities of the media were decreased in silica-treated mesothelial cell and macrophage cultures but not in the media of fibroblast cultures. These results suggest that mesothelial cells, like macrophages, can interfere with the protein synthesis of fibroblasts and thus contribute to the regeneration of mesothelium after injury and to the formation of adhesions.

Animals↗
PubMed1980

Energy metabolism of the peritoneal membrane in silica-induced peritonitis. A biochemical and enzyme histochemical study.

Oxygen and glucose consumption and lactate production of the peritoneal membrane and intra-abdominal adhesions were measured in rats after a single intra-peritoneal colloidal silica injection. Enzyme histochemical studies were made of lactate dehydrogenase, succinate dehydrogenase, NADH2-diaphorase, NADPH2-diaphorase, glucose-6-phosphate dehydrogenase, glutamate dehydrogenase, acid phosphatase, leucylaminopeptidase and alkaline phosphatase in the peritoneal membrane. Anaerobic glycolysis comprises 47% of the total glucose consumption in the the normal peritoneum. Glucose consumption and lactate production of the peritoneal membrane increased sharply in the early phase of silica-induced peritonitis and stayed at a high level for a week indicating an enhanced anerobic metabolism. Oxygen and aerobic glucose consumption increased more slowly than anaerobic glucose consumption and reached their maxima 1 week after silica injection, indicating that the rate of aerobic metabolism is also higher in chemical peritonitis than in the controls. On the other hand, glucose consumption and lactate production increased in a parallel fashion in adhesions and in the peritoneum in the early phase of peritonitis. However, the maximum and later levels were less in adhesions than in the peritoneum. In the enzyme histochemical study high activities of enzymes indicating anaerobic energy metabolism and metabolism via the pentose phosphate shunt were seen in cells of the peritoneal membrane during the early phase of peritonitis. No activity was identified in enzymes indicating aerobic energy metabolism and increased catabolism before the end of the first week.

Animals↗
PubMed1980

Wound infections in abdominal surgery. A prospective study on 696 operations.

A prospective analysis of wound infections in abdominal surgery was carried out in the Department of Surgery, University of Turku, during two 3-month periods. Excluding vascular and urologic surgery altogether 696 abdominal operations were performed. The overall wound infection rate was 9.8%. According to the wound classification the rates of wound infection were the following: clean wounds 4.2%, clean contaminated 9.1%, contaminated 14.4%, and dirty wounds 28.8%. Factors promoting wound infection rate included high age of the patient, associated medical illnesses, prolonged preoperative hospitalization, prolonged duration or extensiveness of the procedure, and missing peritoneal lavage in patients with peritonitis, intestinal strangulation or gross abdominal contamination. The infection rate in acute surgery (12.4%) was higher than that in elective procedures (7.6%). S. aureus was the most common bacteria in wound infections after clean surgery while E. coli dominated in cultures from infected wounds after contaminated surgery. Patients with wound infection were prome to develop other postoperative infections and lung atelectases. The mean nursing time of patients with wound infection was 7 days longer than in uninfected patients. Mortality in patients without wound infections was 1.6% and in patients with wound infection 11.8%.

Abdomen↗
PubMed1980

Effect of peritonitis on oxygen consumption by various tissues and peritoneal fluid cells.

Oxygen consumption by various tissues and peritoneal fluid cells was investigated in silica-induced adhesion disease and fecal peritonitis in rats. Intraperitoneally injected colloidal silica produced chemical peritonitis with a typical acute inflammatory reaction of peritoneal fluid cells showing marked phagocytosis by macrophages. The quantity of cells in the peritoneal fluid as indicated by the content of DNA achieved its maximum within 2-4 days. At the peritoneal surface, abundant proliferative reaction occurred already 2-3 days after silica injection, followed later by aggregation of collagen fibres and finally by peritoneal hyalinization. Oxygen utilization by various tissues--such as liver, kidney, heart, skeletal muscle, lung, spleen and intestine--increased by 20-80% above normal during the first 2 days after silica injection and returned to the original level within the following 5 days. In comparison, fecal peritonitis resulting in death of the animals within 12-36 hours caused a transient fall in tissue oxygen consumption at 12 hours. In the peritoneal fluid of rats injected with silica, oxygen utilization per DNA decreased by more than 50% from the original level during the first 24 hours and remained approximately 20% below normal thereafter. It is concluded that at the early phase of silica-induced peritonitis, oxygen consumption increases both locally in the abdomen and in distant tissues.

Animals↗
PubMed1979

Nucleic acid and sulphated glycosaminoglycan synthesis in the peritoneal membrane and in intra-abdominal adhesions in rat as affected by silica-induced peritonitis.

The synthesis of DNA, RNA and glycosaminoglycans was studied in the peritoneal membrane and intra-abdominal adhesions formed in rats after a single colloidal silica injection. The concentration of DNA and RNA increased from the first day of peritonitis reaching the maximum at 4--7 days in both the peritoneum and adhesions. On the other hand the synthesis of radioactive DNA and RNA from 3H-thymidine and 3H-cytidine increased during the first 12 hours and was maximal at 24 hours in the peritoneum and at 48 hours in the adhesions. Although the contents of uronic acids were maximal at 24 hours in the peritoneum and at 2--4 days in the adhesions, the maximal synthesis rate of sulphated glycosaminoglycans was observed at 5 days in the peritoneum and at 7 days in the adhesions. The difference in the uronic acid concentration and radioactivities of glycosaminoglycans was probably due to increased permeability of the peritoneal membrane and exudation. Earlier we observed that protein synthesis was maximal at 7 days and that of collagen at 3 weeks. On the basis of these and the present results it is obvious that the order of synthesis of these connective tissue components in the peritoneum after chemical peritonitis follows the pattern of tissue reaction in wound healing and in experimental subcutaneous granuloma formation. However, the activation of nucleic acid and glycosaminoglycan synthesis occurs promptly without any or with a very short lag period in the peritoneal mesenchymal tissue.

Animals↗
PubMed1979

Effect of a deproteinized blood extract on experimental granulation tissue.

The present work was undertaken to study the effects of a deproteinized extract of calves' blood (Solcoseryl) on developing granulation tissue in rats. Cylindrical hollow viscose cellulose sponge implants were used as an inductive matrix for the growth of granulation tissue. In the first, sham group the implants were treated daily by withdrawing 1 ml of wound fluid from the central dead space of the implant and then re-injecting the fluid. In the second, experimental group the aspirated wound fluid was replaced by a corresponding volume or Solcoseryl. Analyses of wound fluid and granulation tissue were carried out 4, 10 and 21 days after implantation. A statistically significant increase of granulation tissue hemoglobin (+21%) was observed at 10 days in the Solcoseryl group as compared with the sham-treated rats, indicating an enhanced capillary ingrowth. Concurrently, the mean amount of DNA in the Solcoseryl-treated tissues was elevated by 48% over the level of the sham-treated group, demonstrating an augmented cellularity of granulation tissue. At 21 days the mean amount of collagen hydroxyproline of the Solcoseryl group was 31% above the level measured in the sham-treated animals. PO2, PCO2 and pH in the wound fluid and the amounts of RNA and uronic acids showed no essential differences between the two groups. These data demonstrate a stimulatory effect of Solcoseryl on several aspects of granulation tissue formation: augmented vascularization, elevated cellularity and subsequent enhancement in the accumulation of collagen.

Animals↗
PubMed1976

Peritoneal reaction in acute appendicitis. A biochemical study.

The present study shows that appendicitis and its associated peritoneal inflammation produce microscopic and biochemical changes in the peritoneal membrane. With increasing age, the peritoneal concentrations of DNA, RNA, nitrogen, hydroxyproline, and uronic acids seemed to decrease. In general the greatest chemical changes were observed in younger age groups between the control and peritonitis patients. The amounts of DNA and RNA reflecting the cellularity of the peritoneum were affected most clearly. The location of the appendicular process and the severity of the disease markedly influenced the chemical composition of the peritoneum, whereas the duration of the disease appeared to have no effect on the results. In peritonitis, the concentrations of uronic acids and non-collagenous nitrogen increased markecly, while the concentrations of hydroxyproline and the hydroxyproline/nitrogen ratio decreased. Meseneric lymphadenitis produced no significant changes in the biochemical parameters.

Acute Disease↗
PubMed1975

Intraperitoneal oxygen and carbon dioxide tensions in experimental adhesion disease and peritonitis.

Intraperitoneal oxygen and carbon dioxide tensions were studied in rats during silica-induced adhesion formation or fecal peritonitis. Measurements of PO2 and PCO2 in the abdominal cavity were performed by means of an implanted Silastic tonometer. During active adhesion formation one to three weeks after administration of silica, the intra-abdominal PO2 decreased by 50 per cent from normal whereas the intra-abdominal PCO2 and the rate of oxygen consumption in the peritoneum were elevated. Progressing peritonitis also resulted in decreased intraperitoneal PO2 and increased accumulation of carbon dioxide in the peritoneal cavity. In rats with peritonitis the rate of oxygen consumption in the peritoneal exudate clearly exceeded that in the peritoneal membrane.

Animals↗
PubMed1975

Energy metabolism of experimental wounds at various oxygen environments.

Energy metabolism of healing tissue was studied in experimental wounds of rats chronically breathing 11% O2, air or 55% O2. Increasing oxygen supply elevated both PO2 and PCO2 in the wound tissue. At the early phases of healing hypoxic wounds contained less DNA than normoxic or hyperoxic tissues. In hypoxia the accumulation of wound collagen was clearly retarded. Furthermore, tissue taken from wounds healing in hypoxic environments and tested ex vivo in air showed decreased capacity for glucose utilization, lactate production and oxygen consumption. Concentrations of AMP, ADP and ATP in repair tissue increased as healing progressed. The more oxygen available the higher the amounts of ADP and ATP. The AMP content was not affected by changes in local oxygen tension. These results support the earlier concept that the supply of oxygen in healing tissue may be rate-limitimg. Reduction of available oxygen either by systemic hypoxia or by increased diffusion distance impedes healing.

Animals↗