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Biomedical subjects

K von Smitten

Publications and source records attributed to K von Smitten.

At least 73 records · Page 4Linked to original sources
PubMed1988

Replantation service in Helsinki University Central Hospital 1980-1985.

A replantation service is a routine part of medical services. The best results are obtained when the work is centralized. In Finland five university hospitals have a replantation service. In the Helsinki University Central Hospital, 94 severed parts of the upper limb were replanted/revascularized in 1980-85. The amputation injury requiring replantation was most often a thumb avulsed by the driving axle of a tractor. The patients came from all over the country, and the short time span between the initial injury and admission to hospital--2.4 hours an average in 1985--shows that transport of these patients is not a problem in Finland. The mean duration of surgery was 6.9 hours. Most of the operations took place in the late afternoon, evening or at night. 16% of the cases needed immediate reoperation because of vascular problems. Later, over 40% of the cases underwent secondary procedures. Most of the patients returned to their former employment. In long-term follow-up, however, nine out of ten patients reported that the replanted organ was intolerant to cold. Therefore, with the exception of the thumb, single finger replantation should not be a routine procedure in a cold climate such as that encountered in Finland. A replantation service requires a minimum of four surgeons qualified in plastic surgery or hand surgery. The operating theatre will be in use through the night. Nurses, physiotherapists and occupational therapists must be specially trained. The surgeon must be prepared to perform multiple reconstructive procedures, both immediately and later on.

Adult↗
PubMed1988

Abdominal rectopexy and sigmoid resection (Frykman-Goldberg operation) for rectal prolapse.

Transabdominal posterior rectopexy with resection of the redundant left colon (Frykman-Goldberg operation) was performed on 48 selected patients with complete rectal prolapse. Uterine suspension was also performed on most of the women. The 30-day mortality rate was 2.1%. Prolapse recurred in 4 (9%) of the 45 patients followed up for 1-10 (mean 4.3) years. There were no complications attributable to bowel resection or anastomosis. Adequate data on both preoperative and postoperative anal function and bowel habit were available in 41 cases. All but two of the 32 patients with associated incontinence experienced improved anal control after the operation (9 regained normal continence). Bowel habit improved in 23 patients (56%), especially in those with chronic constipation. No patient reported increased problems of bowel management. The operation does not involve the risks associated with implantation of foreign material and can be especially beneficial for constipated patients with rectal prolapse who are fit for major abdominal surgery.

Adult↗
PubMed1987

The rabbit ear pedicle flap. A new model for evaluating factors affecting the circulation in flaps.

Laser Doppler flowmetry and transcutaneous oximetry were compared regarding their speed and accuracy in detecting occlusion of the artery of an experimental rabbit ear pedicle flap. The laser Doppler flowmeter showed a significant decrease in flow and the transcutaneous oximeter showed a significant decrease in oxygen tension within one minute after occlusion of the artery. A significant increase in flow was observed within one minute, and a significant increase in oxygen tension readings was observed one minute after the artery was opened. A steady state after opening the artery was reached sooner for the laser Doppler flowmeter readings. This study suggests that laser Doppler flowmetry and transcutaneous oximetry are equally fast and accurate in detecting changes in blood flow to a pedicle graft. These methods also have equally good reproducibility. Repeated clampings within a 30 min period did not affect the measured parameters.

Animals↗
PubMed1986

Histochemical examination of energy metabolism in aortic vein grafts in rats.

The duration of the presumed metabolic depression of syngeneic vena cava to aorta transplants was determined in rats and the site and type of energy metabolism in the vein grafts assessed. The aerobic metabolic activity was measured from the histochemical reactivity of the enzymes, succinate dehydrogenase and cytochrome oxidase, and the anaerobic activity by staining with lactate dehydrogenase. The activity of the hexose-monophosphate shunt was assessed by the histochemical demonstration of glucose-6-phosphate dehydrogenase. Sixteen hours after grafting a pronounced metabolic depression was noted. Recovery occurred 24 hours after transplantation. The most intense staining was from lactate dehydrogenase in the vein grafts and in the non-transplanted veins. At the end of the observation period of four months the grafts were definitely more strongly stained than the non-transplanted veins, with most of the activity in the thickened intima. This layer had a metabolic profile resembling that of the media of the adjacent aorta.

Animals↗
PubMed1986

Long-term results of sigmoidostomy in patients with anorectal malignancy.

The long-term results with permanent end-sigmoidostomy were studied in 54 patients after abdominoperineal excision of the rectum for anorectal malignancy. The patients were re-examined 1-8 years postoperatively, when the function and late complications of the end-sigmoidostomy and the need for reconstructive procedures were assessed. An attempt was also made to evaluate the patients' quality of life. Only one patient reported severe impairment of social life due to the enterostomy. The main surgical problem was paracolostomy hernia (48% of the series), but revisonal surgery because of hernia was necessary in only two cases. Stomal stenosis (5.6%) in no case required reoperation. Peristomal eczema (5%) was always manageable with local treatment. The results indicated that the quality of life with end-sigmoidostomy is reasonably good, and this should be kept in mind when deciding on type of operation for low rectal malignancy.

Adult↗
PubMed1985

Collagens, laminin, fibronectin, and cytoskeletal composition of cells in syngeneic aortal vein grafts in the rat.

The supradiaphragmatic vena cava of the rat was transplanted to the abdominal aorta in syngeneic recipients. The cells and the connective tissue matrix of these grafts were studied 3 days to 12 weeks after transplantation by immunofluorescence staining of the cytoskeletal proteins desmin, vimentin, and myosin. The matrix proteins, collagen Types I and III, laminin, fibronectin, and fibrin(ogen) were similarly demonstrated. Blood coagulation Factor VIII was used as a marker for endothelial cells. Inflammatory cells invaded the graft during Week 1, but later on the grafts were crowded with cells containing vimentin. Intimal thickenings developed already after 1 week. Smooth muscle cells containing desmin proliferated in these thickenings. After transplantation collagen Type I increased in the graft, but collagen Type III rather decreased. During the phase of intense proliferation of smooth muscle cells the media contained a rich matrix of diffusely distributed laminin. The laminin of older grafts was confined mostly to the subintimal zone and to the intimal plaques.

Animals↗
PubMed1985

The effect of perfusion on post-operative viability in the replanted rabbit ear: measured by laser Doppler flowmetry and skin temperature.

The effect of perfusion by heparinized Ringer solution on post-operative microcirculation in rabbit ear replants was studied. One ear in each of five rabbits was replanted after perfusion with heparinized Ringer solution and these were compared with five replantations of rabbit ears without perfusion. The ears were studied post-operatively for 2 1/2 days by skin temperature monitoring and Laser Doppler Flowmetry (LDF). During the first day after replantation the perfused ears had better capillary flow, whereafter no significant differences were noted. LDF was more sensitive to changes in capillary blood flow, and this seems to make the reproducibility of LDF poor. It is, however, a suitable method for continued observation of post-operative viability.

Animals↗
PubMed1984

Innervation of syngeneic vein grafts in the rat. The regeneration of adrenergic nerves.

Regeneration of adrenergic nerves was studied sequentially in segments of the supradiaphragmatic inferior vena cava transplanted from one rat into the abdominal aorta of another of the same inbred strain. Nontransplanted vein segments were examined as controls. The adrenergic nerves were demonstrated by using the glyoxylic acid-induced fluorescence method and the formaldehyde-induced fluorescence method for the demonstration of cathecholamines. A total of 16 syngeneic grafts were examined 3, 5, 8, 16, 27, and 32 weeks after transplantation. Three additional grafts were wrapped inside a silicone tube during the operation to prevent regeneration of nerves from the surroundings. These rats were then killed 8 weeks after the operation. In the control specimens the supradiaphragmatic inferior vena cava was innervated with a rather dense plexus of adrenergic nerves showing varicosities. No nerves were seen in the 3-week-old grafts. In the 5-week-old grafts some sparsely distributed solitary nerve fibres were seen. In the 8-week-old grafts sparsely distributed regenerated nerves reinnervating the vasa vasorum and nerve plexa were observed. The 16-, 27-, and 32-week-old grafts showed rather poorly innervated areas and areas where the nerve plexus was dense. One graft showed very dense reinnervation with morphologically abnormal adrenergic nerves forming "droplet fibers" and showing dense accumulations of catecholamines. The grafts surrounded with silicone tubes had no adrenergic nerves and showed only some regenerated nerves crossing the suture line. The results of the present study indicated that syngeneic inferior vena cava transplanted into the abdominal aorta will be reinnervated with adrenergic nerves. The pattern of the nerve regeneration remains incomplete and patchy.

Animals↗
PubMed1984

Innervation of syngeneic vein grafts in the rat. The regeneration of cholinesterase positive nerves.

The regeneration of cholinesterase positive nerves into segments of the supradiaphragmatic inferior vena cava transplanted from one rat into the abdominal aorta of another rat of the same inbred strain and sex were studied, using a histochemical thiocholine method for the demonstration of cholinesterase. Iso-OMPA and BW-284 C 51 were used as inhibitors for nonspecific cholinesterase (nsChE) and acetylcholinesterase (AChE), respectively. A total of 12 grafts were examined 3, 5, 8, 16, 27 and 32 weeks after transplantation. One single regenerating nsChE reactive nerve was seen near the suture line in a 3-week-old graft. Some solitary regenerating nerves were regularly seen in the grafts at 5 weeks. Eight weeks after grafting some solitary sparsely distributed nerves were found in the outer layers of the graft. In the 16-, 27-, and 32-week-old grafts, nsChE reactive nerves and small nerve bundles were running either solitary or forming nerve plexa in addition to nerves in the vicinity of vasa vasorum. These regenerated nsChE reactive nerves are probably vasomotor in nature. The AChE reaction showed a clear activity in the intimal layer of the grafted veins. No AChE reactive nerves were seen in the 3-, 5-, and 8-week-old grafts. Only occasional AChE positive nerves were observed 16, 28 and 32 weeks after transplantation. These nerves are probably sympathetic cholinergic nerves.

Acetylcholinesterase↗
PubMed1983

Connective tissue changes and collagen metabolism in syngeneic vena caval grafts in rats.

An attempt was made to determine if changes occurring in connective tissue and collagen metabolism of vein-to-artery grafts arose from the trauma of transplantation as such or from the higher pulsatile pressure. Segments of the supradiaphragmatic inferior vena cava were therefore transplanted to the infrarenal vena cava in syngeneic pairs of rats. The sequential changes in hydroxyproline concentration, 3H-proline incorporation and the histologic appearance of collagen, elastic fibres and fibronectin were noted. Comparisons were made with previously reported changes in syngeneic venoartery grafts in rats. The initial changes, probably resulting from the transplantation trauma, were similar in the veno-vein and veno-artery grafts. Subsequent changes, however, were less pronounced in veno-vein than in veno-artery grafts. The study thus suggests that these changes in vein-to-artery grafts are due partly to the transplantation trauma, but mainly to the increased pressure in the new environment.

Animals↗
PubMed1982

Repair of incisional hernias by F. Langenskiöld's operation.

One hundred and fifteen patients underwent the Fabian Langenskiöld repair of an incisional hernia. 81 patients were studied retrospectively in a physical examination by the authors. The follow-up period ranged from 12 months to 15 years, with a mean of 6 years and 2 months. Wound infection occurred in 35.8%. Small herniations and recurrencies were observed in 31%. Five patients had large recurrent hernias (6.2%) reaching preoperative size. Despite the high rate of recurrencies and infections this method was found valuable because it enables restoring of a firm abdominal wall even in large incisional hernias without implantation of foreign materials.

Female↗
PubMed1981

Bursting strength of syngeneic aortic vein grafts in the rat.

Mechanical strength of the supradiaphragmatic part of the vena cava transplanted from one rat into the abdominal aorta of another rat of the same inbred strain was studied before transplantation, as well as 3 days and 1, 2, 3 and 4 weeks after transplantation. Bursting pressure was determined by distending the specimens with water at a constant infusion rate. The diameter of the specimens was measured at the moment of burst by a shadow technique, and the wall thickness by a micrometer on formalin-fixed and paraffin-embedded transverse sections, thus enabling calculation of bursting wall tangential and circular tension. No significant changes in bursting pressure were observed within 2 weeks after transplantation. Three and 4 weeks after transplantation a significant increase in bursting strength was observed. This increase coincided with the increase in collagen concentration previously reported. The previously reported initial decrease in collagen concentration did not, however, result in significant changes in the bursting strength. It is suggested that the increase in the thickness of the vein wall due to the increase of components other than collagen compensates for the loss of collagen.

Animals↗
PubMed1981

Breaking strength and suture holding capacity of syngeneic aortic vein grafts in the rat.

The breaking strength of the supradiaphragmatic inferior vena cava transplanted from one rat into the abdominal aorta of another rat of the same inbred strain and the same sex was studied before and during the first 4 weeks after transplantation. Breaking strength was determined by testing segments of the abdominal aorta with interposed vein graft using a tensiometer which indicated the breaking force and site. The suture-holding capacity of the wall of the abdominal aorta, the non-transplanted inferior vena cava and the vein grafts was tested by determining the force required to disrupt an anastomosis made by 4 sutures of 8-0 polypropylene. One week after transplantation the breaking strength and suture-holding capacity of the vein grafts was significantly lower than before surgery. Two weeks after transplantation the graft segment was stronger than preoperatively, and also stronger than the adjacent aorta in three cases out of five. Four weeks after transplantation all except one of the six tested segments disrupted at the aorta. The suture-holding capacity of the graft wall was significantly greater four weeks after transplantation than in non-transplanted vein segments. These changes in breaking strength and suture-holding capacity correspond to the decrease and subsequent increase in collagen concentration of the vein grafts previously reported.

Animals↗
PubMed1980

Fibronectin and atherosclerosis.

Fibronectin is a polymorphic glycoprotein of plasma, other body fluids and connective tissue, and it occurs in an insoluble and a soluble form. Insoluble fibronectin is found associated with basement membranes and in loose connective tissue matrix as well as in the pericellular matrix formed around cultured adherent cells, such as endothelial, fibroblastic and smooth muscle cells. In these positions fibronectin apparently functions as a substrate for cell attachment and as a scaffold for cell migration and movement. Soluble fibronectin, present e.g. in the circulation (300 micronm/ml) exhibits some important interations with other proteins. It is covalently cross-linked to fibrin during thrombus formation and binds to collagen. Fibronectin is released from platelets during their aggregation and soluble fibronectin potentiates the action of plasminogen activator. We have detected fibronectin in the sub-endothelium, in the matrix of smooth muscle cells of the media and in the adventitia of arteries. By using immunohistological techniques we have further found that fibronectin is prominent in atherosclerotic lesions of the intima, especially in developing fibrous plaques. Fibronectin was also prominent in experimentally induced atherosclerotic lesions. These findings suggest that fibronectin is an indicator of connective tissue formation in atherosclerotic processes and that the protein can have a role in their pathogenesis.

Arteriosclerosis↗
PubMed1980

Connective tissue changes in syngeneic aortal vein grafts in rats.

The supradiaphragmatic inferior vena cava was syngeneically transplanted into the infrarenal part of the abdominal aorta in rats of inbred strains. The initial histologic changes coincided with the changes usually seen in wound healing during the inflammatory phase and the phase of fibroplasia. Later the reparative process occurred predominantly in the luminal part of the vein wall, and was usually seen as intimal hyperplasia. In some grafts this process caused a narrowing of the lumen. In this particular experimental model the thickening of the intimal layer was mainly due to organization of fibrin layering thrombus. This was shown by detection of lamellar fibrin deposits and a high concentration of fibronectin in this layer. A large amount of fibronectin was detected in and around the proliferating fibroblasts and in thrombi. This explains the high concentration of fibronectin in the proliferating intimal layer of the graft.

Animals↗
PubMed1980

Collagen metabolism in syngeneic aortal vein grafts in the rat.

The sequential changes in hydroxyproline concentration and in vivo 3H-proline incorporation in arterialized grafts of the supradiaphragmatic inferior vena cava have been studied. These grafts were transplanted from one rat to the abdominal aorta of another rat of the same inbred strain, i.e., syngeneic grafts. The hydroxyproline (collagen) concentration decreased to half of its pregraft value one week after the transplantation and thereafter increased again, reaching its peak value 4 weeks after transplantation. The pregraft level of collagen concentration was not reached within the observation period of 12 weeks., The incorporation of 3H-proline increased and reached its peak value one week after transplantation. The values then levelled off and one month after the transplantation were slightly elevated. These results indicate that the reduction of collagen concentration after grafting was due to an increased breakdown, which was compensated by increased collagen synthesis. This probably signifies that the collagen in the vein wall is remodelled as a response to the altered hemodynamic milieu following its insertion to the arterial circulation. The collagen concentration did not reach pregraft level. This is most likely due to a relative increase of ground substance, smooth muscle cells and elastin in the vein wall.

Animals↗