Biomedical subjects

J Ahonen

Publications and source records attributed to J Ahonen.

256 records · Page 15Linked to original sources

PubMedDate not supplied

Connective tissue growth factor in indomethacin-induced rat gastric ulcer.

The healing of gastric ulcers requires not only the complete epithelial covering but also the restitution of connective tissue. Transforming growth factor-beta (TGF-beta) and its downstream mediator, connective tissue growth factor (CTGF), are potent stimulators for connective tissue formation during wound healing. The expression of TGF-beta, CTGF and type III collagen mRNA in indomethacin-induced gastric ulcers in rat, was investigated by Northern blot analysis. We also examined the localization of CTGF producing cells by in situ hybridization. Northern blot analysis showed expression of TGF-beta mRNA on days 1 and 3 after indomethacin administration, expression of CTGF mRNA on days 1, 3 and 7 and type III collagen mRNA expression on days 1, 3, 7 and 12, respectively. Control animals showed no expression of TGF-beta, CTGF or type III collagen mRNA. In situ hybridization showed CTGF mRNA positive cells on days 1, 3 and 7 after ulcer induction in fibroblast-like cells and in some of the blood vessels. Thus our findings indicate that growth factor CTGF, together with TGF-beta, participates in gastric ulcer healing by regulating connective tissue formation and angiogenesis. These results are compatible with the role of CTGF as a downstream mediator of TGF-beta effects.

Animals↗

PubMedDate not supplied

Posttransplantation monitoring of high-density lipoprotein-associated serum amyloid A protein: a new diagnostic aid in the detection of renal allograft rejection.

The concentrations of serum amyloid A protein, a high-density lipoprotein-associated protein synthesized in the liver, were monitored in 66 recipients of cadaveric renal allografts. Acute graft rejection episodes were associated with dramatic elevations of serum amyloid A. Electrofocusing and immunoblotting of rejection sera showed a polymorphic serum amyloid A pattern similar to that obtained with control (apo) serum amyloid A isolated from the high-density lipoprotein fraction of plasma. Rejections in patients receiving cyclosporine alone as posttransplantation immunosuppressive medication were characterized by significantly higher serum amyloid A levels than in those receiving cyclosporine in combination with methylprednisolone. Due to the dramatic rejection-induced serum amyloid A elevation, limit values could be used which combined high sensitivity (87-96%) with reasonably high predictive value of a positive test (82%). The serum amyloid A test was applicable also in patients with initially nonfunctioning or poorly functioning grafts. It is concluded that monitoring of the serum amyloid A concentrations offers a valuable noninvasive aid in the early diagnosis of acute renal allograft rejection, including patients with acute tubular necrosis of the graft.

Adult↗

PubMedDate not supplied

The effect of stenosis on collagen metabolism in the colonic wall. Studies in the rat.

The influence of colonic stenosis resulting in faecal loading was investigated in regard to collagen metabolism in the intact colonic wall. The collagen content was increased in the left colon proximal to the stenosis, due to enhanced collagen synthesis. The collagen concentration fell significantly, however, as noncollagenous substances increased more than collagen. Collagen concentration clearly can be misleading as an indication of the actual amount of collagen. The enhanced rate of collagen turnover with collagen accumulation proximal to stenosis requires further analysis in regard to its importance for healing capacity.

Anastomosis, Surgical↗

PubMedDate not supplied

The use of both kidneys obtained from pediatric donors as en bloc transplants into adult recipients.

Surgical technics for the excision and transplantation of paired renal graft from pediatric donors to adult recipients is described. Experience based on literature and on two own transplantations speaks for the adoption of this policy. The operation is technically advantageous. The double transplant provides a greater functioning renal mass as compared with the use of a single pediatric graft. In case of a rejection which can result in loss of some renal capacity, the double transplant is more likely to be able to maintain sufficient fuction even in adult recipients. The importance of a properly performed donor operation is stressed.

Adult↗