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Biomedical subjects

T Waris

Publications and source records attributed to T Waris.

At least 55 records · Page 3Linked to original sources
PubMed1991

Effect of perivascular sympathectomy on distal adrenergic innervation in the hands of monkeys.

Perivascular sympathectomy has been thought to cause distal adrenergic denervation. We performed perivascular sympathectomy for a distance of 1 cm. on two common digital arteries in the right hands of two anaesthetised Macaca arctoides monkeys. Four days later, samples were taken for glyoxylic acid-induced fluorescence examination of the operated and opposite control hand. The distal adrenergic nerves were morphologically normal in appearance after the perivascular sympathectomy. The operation should perhaps be called adventitectomy rather than perivascular sympathectomy and its positive effects may be due to the loss of adventitial support for the vasospastic arteries rather than adrenergic denervation.

Adrenergic Fibers↗
PubMed1991

Failure of perivascular sympathectomy to remove adrenergic nerves from peripheral vessels of the rabbit ear skin.

A perivascular sympathectomy was performed at the base of the ear artery in 11 New Zealand white rabbits. Two days later three were killed, and the central nerve was cut in the remaining eight. The contralateral ear served as a control. Specimens were taken from the distal parts of both ears two days later and the glyoxylic acid-induced fluorescence method was used to show the adrenergic nerves. The arteries of the normal, control ear were surrounded by a dense plexus of fluorescent adrenergic nerves, which were abolished by perivascular sympathectomy only in the segment from which the adventitia had been removed. The adrenergic innervation was normal proximal to the site of perivascular sympathectomy, but there was a short segment of the central vessel distally in which it was diminished. No changes in adrenergic innervation were found in the distal third of the rabbit ear.

Animals↗
PubMed1991

The return of sensitivity to cold, warmth and pain from excessive heat in free microvascular flaps.

Recovery of sensitivity to cold, warmth and pain caused by excessive heat in various types of free microvascular flaps was studied psychophysically in 27 patients who had undergone such operations four months to four years earlier. A thermal stimulator based on the Peltier principle and controlled by a microprocessor was used to measure the sensitivity to temperature in the transplants. The results were compared with the measured thresholds in the opposite sites in corresponding normal body areas. The present study showed that sensitivity to cold, warmth, and pain caused by excessive heat did return to some free microvascular flaps. According to the measurements the sensation started to return after 6 months in some flaps, and all types of thermal stimuli were felt by one patient as early as 10 months after operation. The return was more pronounced in younger people and in smaller flaps. If the hands, feet, or head defects were reconstructed with a thin skin flap (posterior aspect of thigh, dorsum of foot, or subscapular) the recovery of sensitivity was verified. Sensation returned to the musculocutaneous and osteomusculocutaneous transfers if they were on the hands or the head, or if they were sutured to healthy tissue with normal sensation. The main advantage of the psychophysical sensory testing method that we used is that it gave exact numerical data that made it possible to compare results among the different patient groups and even those obtained at different clinics and laboratories.

Adolescent↗
PubMed1990

Effect of distension on adrenergic innervation of the rat urinary bladder.

The effect of distension on adrenergic innervation was investigated in the rat urinary bladder. Bladders were distended for 3 h by forced diuresis and balloon obstruction, and specimens were taken from the bladder dome, body and neck for the demonstration of glyoxylic acid-induced fluorescence of catecholamines. Depletion of catecholamines started after 10 h and was almost complete after 2 days. The fluorescence had recovered part way after 5-7 days and was practically normal after 21 days. Small, intensely fluorescent (SIF) cells in the ganglia continued to leak catecholamines throughout the 21-day study period. The primary clinical success of distension therapy for the treatment of unstable bladder may be at least partly due to a reversible disturbance in the function of the adrenergic nerves, which have an excitatory alpha-adrenergic dominance in such cases, but the persistent leakage from SIF cells raises the question of whether distension causes prolonged disturbances in bladder function.

Animals↗
PubMed1990

Hypopharyngeal reconstruction with free microvascular jejunal transfer after total laryngopharyngectomy.

One-stage laryngopharyngeal free microvascular jejunal transfer after total laryngopharyngectomy was performed in 8 patients with advanced laryngopharyngeal cancer. The study showed that this was a relatively safe and time-saving method for hypopharyngeal reconstruction after radical cancer surgery. It improved the quality of life of the patients, allowing normal alimentation, though in some cases only temporarily due to the highly malignant nature of the disease.

Aged↗
PubMed1989

Sequential changes of noradrenaline content of vein grafts in rats: quantitative estimation by high-performance liquid chromatography using electrochemical detection.

Supradiaphragmatic inferior vena cava was transplanted end-to-end into the abdominal aorta of 11-week-old rats of the same inbred strain and same litter using microvascular technique. The grafts were removed 3 days, 4, 8, 16, and 35 weeks postoperatively, and their noradrenaline (NA) content was estimated by high-performance liquid chromatography using electrochemical detection. The amount of NA was significantly lower (P less than .001) in all vein grafts as compared to nontransplanted vena cava. The substantial decrease of NA in the vein grafts throughout the observation period indicates a persistent denervation of the transplant.

Animals↗
PubMed1989

Regeneration of cold, warmth and heat-pain sensibility in human skin grafts.

Recovery of cold, warmth and heat-pain sensations in skin grafts was studied psychophysically in 22 patients who had had split skin grafts transplanted over muscle fascia 1 to 4 years earlier. A thermal stimulator based on the Peltier principle and controlled by a microprocessor was used to measure the thermal sensitivity of the grafts. Control measurements were obtained from the corresponding opposite side of the body. Cold sensitivity was present in 14 grafts (from 1-4 years old). However, with one exception, the threshold for cold sensation remained higher than normal in all patients. Warmth sensitivity was present in 6 grafts (from 1-4 years) which were all also sensitive to cold. Heat-pain sensitivity was present in 8 grafts. If the warmth and heat-pain sensibility had recovered, the sensation threshold was closer to the normal value than that for cold. In 7 grafts (from 1-3 years) no recovery was obtained.

Adult↗
PubMed1989

Recovery of sensation in free flaps.

A clinical study of touch, pain, warm and cold stimuli and two-point discrimination was performed in 27 free flaps four months to four years after the microsurgical procedure. There were 5 free skin flaps (2 with nerve suture), 15 musculocutaneous, 4 muscle-covered with split skin grafts and 3 osteomusculocutaneous flaps transplanted to various sites on the body. The results show full or nearly full recovery of touch and pain sensation in all free skin flaps. The musculocutaneous and osteomusculocutaneous free flaps developed good sensation if firmly grown onto the healthy recipient skin with normal sensation. Muscle flaps covered with split skin grafts and all flaps surrounded by scar tissue had a clinical absence of sensation. This study and our earlier findings of the regeneration of nerves in free skin grafts, in skin flaps and in experimental free flaps, lead us to suggest that the healthy denervated skin of the free flap provides a strong neurotrophic stimulus to the cut cutaneous nerves in the edges of the recipient skin. Cutaneous nerves freely regenerate in the loose subcutaneous tissue of the flap. We therefore conclude that all free flaps with skin islands have a potential for developing sufficient protective touch and pain sensation and even some superficial sensitivity.

Adolescent↗
PubMed1988

Degeneration and regrowth of adrenergic nerves after microvascular anastomosis. A fluorescence histochemical study on end-to-end anastomoses of femoral vessels in the rat.

The normal femoral artery and its branches were found to be innervated with a dense network of adrenergic nerves. The nerve plexus around the vein was sparse. Adventitial stripping of the femoral vessels, with or without division and reanastomosis, caused local disappearance of catecholamine fluorescence in the stripped area. The distal adrenergic innervation remained normal if the femoral nerve was left intact. Division of the femoral nerve, alone or in combination with blood vessel division and reanastomosis, caused total disappearance of catecholamine fluorescence from the adrenergic nerves of the entire distal neurovascular tree examined. At the end of the observation period of 36 weeks from the time of division of the nerve, artery and vein with subsequent microvascular anastomosis, numerous adrenergic nerves were observed to have crossed the suture line. The vascular nerve plexus around the femoral vessels was dense in places, but in other places sparse or absent. It seems that the reinnervation occurs not only over the suture line, but also together with other regenerating nerves from the adjacent tissues and by collateral sprouting from adjacent adrenergically normally innervated areas.

Adrenergic Fibers↗
PubMed1988

Adrenergic innervation of aortic patch-grafts in rats.

The regeneration of vascular adrenergic nerves was studied using the glyoxylic acid-induced fluorescence method for the specific demonstration of adrenergic nerves in syngeneic patch-grafts of the right atrium of the heart, vena cava and glutaraldehyde-treated vena cava transplanted into the abdominal aorta of the rat. Glutaraldehyde-treated segments of the supradiaphragmatic inferior vena cava were transplanted into the abdominal aorta of rats as well. At the end of the observation period of 24 weeks limited, patchy and defective innervation was observed in the syngeneic vena cava and atrial patches. No adrenergic nerves were found in the glutaraldehyde-treated vein patch-grafts or vein grafts. Owing to the very poor innervation of atrial and venous patch-grafts the results are not entirely in agreement with the target organ concept of adrenergic nerve regeneration. In this study the suture line around the patch graft probably hampers regeneration of vascular adrenergic nerves in the patches.

Adrenergic Fibers↗
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

Life-threatening complications of cardiac operations and occurrence of myocardial catecholamine bombs.

Myocardial catecholamine bombs (huge local intra-axonal accumulations of catecholamine, mainly norepinephrine, within cardiac tissue) were observed in (right auricular) myocardial biopsy specimens in 16 of 65 adult patients selected randomly from a series of elective cardiac operations. The occurrence of catecholamine bombs was in highly significant correlation (p less than 0.001) with the occurrence of life-threatening complications of cardiac operations (life-threatening arrhythmias [ventricular tachycardias, ventricular fibrillation, asystole], clinically evident perioperative myocardial infarction/postoperative low-output syndrome, death). There was a very close correlation between the occurrence of catecholamine bombs and life-threatening arrhythmias. Life-threatening arrhythmias occurred in 13 patients. Eight of them belonged to the group of 16 patients with catecholamine bombs and five belonged to the group of 49 patients with no bombs; the difference (8/16 versus 5/49) is very clear (p less than 0.001). It was our experience that dangerous arrhythmias related to catecholamine bombs may occur as late as during the second postoperative week. We believe our observations are of considerable clinical importance, because catecholamine bombs are easily identified by fluorescence microscopic examination of right auricular myocardial specimens retrieved intraoperatively, and patients at high risk can then be selected (during the operation) for more extensive and prolonged surveillance and possibly prophylactic treatment.

Adult↗
PubMed1987

Comparison of latissimus dorsi and rectus abdominis free flaps.

This review of 41 latissimus dorsi and 7 rectus abdominis free flaps describes the advantages and disadvantages of these two donor tissues. Flap survival was over 95%. Rectus abdominis carries the greatest area of skin of all the free flaps and makes salvaging of extremities with massive soft tissue loss possible, and it also provides the most elegant small free muscle flap. The latissimus dorsi is suitable for nearly any defect of the body except the foot and the hand because of bulkiness of the tissue and poor development of sensation, and the face because of poor colour match.

Abdominal Muscles↗
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↗
PubMed1985

Multi-score estimation of catecholamine fluorescence for clinical purposes.

Experience accumulated at multi-score semiquantitation of catecholamine fluorescence of glyoxylic acid-treated stretch preparations of human clinical specimens is presented. The methodology and criteria of quantitation are described in detail. For an example, comparison between 3 different methods for analyzing neural-bound noradrenaline in human myocardial tissue in various heart diseases (obtained during the course of cardiac surgery) is presented: Biochemical determination of tissue noradrenaline content multi-score estimation of catecholamine fluorescence of glyoxylic acid-treated stretch preparations microfluorimetric analysis of the same stretch preparations. The results show that the multi-score estimation method gives a reliable concept of the relative amounts of noradrenaline stored in the intrinsic adrenergic nerve net (corresponding closely to the individual and group differences observed at biochemical noradrenaline determination). In addition, possible regional differences, alterations in the structural integrity of the inbuilt intrinsic nerve net, and other structural changes (e.g. pathological catecholamine accumulations) are easily recognized, whereas biochemical estimation cannot give information on structural aspects, which may have important clinical repercussions. Microfluorimetry does not seem suitable for studies on human myocardial specimens for several reasons which are discussed. The method of multi-score estimation of catecholamine fluorescence described and discussed is recommended for other similar and related studies on human clinical materials.

Catecholamines↗
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↗