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G Skalkeas

Publications and source records attributed to G Skalkeas.

At least 19 recordsLinked to original sources
PubMed2005

The use of isobutylcyanoacrylate as a tissue adhesive in abdominal surgery.

BACKGROUND: The use of cyanoacrylate substances as tissue adhesives is of valuable aid in surgery, especially in cases of injuries of the intraabdominal organs, where the haemorrhage is very difficult to control. MATERIALS AND METHODS: We investigated the efficiency of isobutyl-2-cyanoacrylate as a tissue adhesive in the haemostasis and adhesion of different types of wounds in solid and hollow organs. Forty-six dogs underwent single-organ (26 dogs) and combined-organ (20 dogs) procedures; cuneiform excisions of the liver and the spleen, as well as incisions of the small intestine were carried out. The wound surfaces were coated with isobutyl-2-cyanoacrylate and approximated. RESULTS: The majority (91.3%) of the surgical operations were uncomplicated, in which a very good macroscopical and histological result was achieved. Histological examination of the surgical injuries, performed 4 months later, confirmed complete wound healing. CONCLUSION: Isobutyl-2-cyanoacrylate proved to be a very effective tissue adhesive for both solid and hollow organs, even for high risk surgical operations.

Animals↗
PubMed2000

Effect of impaired vasa vasorum flow on the structure and mechanics of the thoracic aorta: implications for the pathogenesis of aortic dissection.

OBJECTIVE: To investigate the alterations of structure and mechanical properties of the aortic wall, resulting from impairment of vasa vasorum flow. METHODS: Eight healthy Landrace pigs were subjected to interruption of vasa vasorum flow to the upper segment of their descending thoracic aorta. Under sterile conditions, the periaortic tissue was excised and the contiguous intercostal arteries were ligated. Ten sham-operated pigs were used as controls. Fifteen days postoperatively, the animals were sacrificed and their upper descending thoracic aortas were removed. Histology, and collagen and elastin content determination by image analysis technique were performed. Mechanical analysis of aortic strips was carried out with a uniaxial tension device and stress-strain curves were obtained. RESULTS: In contrast to normal aortic walls of the control group, histology of the avascular aortas revealed severe ischemic necrosis of the outer media along with abnormal straightening of the elastin and collagen fibers, without significant collagen and elastin content changes. The borderline between the outer ischemic and inner non-ischemic media was sharp, and an outset of dissection was observed at this point. Mechanical analysis showed that at the same level of strain, the ischemic aorta was significantly stiffer at both low (P=0.03) and high strains (P=0. 003). CONCLUSIONS: Impairment of blood supply to the thoracic aorta leads to abnormal morphology of elastin and collagen fibers of the outer media, resulting in increased aortic stiffness under a wide range of stresses. In the clinical setting, decreased vasa vasorum flow, reportedly occurring in arterial hypertension, may increase the stiffness of the outer media of the thoracic aorta and produce interlaminar shear stresses, contributing to the development of aortic dissection.

Aortic Dissection↗
PubMed1999

Surgical treatment for lung hydatid disease.

Lung is the second most common site for hydatid disease after the liver. The aim of this study is to present the clinical symptomatology, diagnostic evaluation, and surgical techniques for the treatment of lung hydatid disease. During the last 25 years, 42 patients with lung hydatid cysts were treated surgically in our department. In four patients there were cysts in the liver and in one case in the spleen. The cysts were located in the right lung in 16 patients (38%), in the left lung in 23 patients (54.8%), and in both lungs in 3 patients (7.14%). Eighteen patients (42.9%) presented with complications: suppuration in one patient (2.4%), rupture to the bronchial tree in 16 patients (38%), and pneumothorax in one patient (2.4%). Diagnosis was established preoperatively in all cases; chest radiography and computed tomography were most helpful for diagnosis. Forty-six operations were performed in 42 patients; three patients with bilateral cysts underwent staged thoracotomies, and one patient was reoperated for recurrent disease. All cases were managed surgically, with several types of radical (34 cases) or conservative (12 cases) procedures. Radical procedures were lobectomy and rarely pneumonectomy, which were used more often during the first half of the study period. Cystectomy with capitonnage, the most commonly performed conservative procedure, was mainly used during the second half of the study period. Postoperative morbidity was 15.2% and the 30-day mortality rate was 0%. In one case there was postoperative hemorrhage that required reexploration. The median hospital stay for uncomplicated cases was 12 days and for complicated cases 21 days. In conclusion, pulmonary hydatidosis often presents with complications requiring emergency surgery. A lung-conserving operation is the treatment of choice for lung hydatid disease and offers a good surgical outcome with a minimal recurrence rate.

Adult↗
PubMed1999

The effect of various types of splenectomy on the development of B-16 melanoma in mice.

Two hundred and sixty CB57BL/J6 mice were used in an experimental protocol designed to investigate the effects of four different varieties of splenectomy on the growth rate of subcutaneously implanted GB-16 melanoma. In addition, the mean and absolute survival of the mice, the histopathology of the tumour and the effects of the same procedures on the immunological status of the tumour-bearing animals as assessed by serum IgG levels and immunoelectrophoresis were determined. The effects of timing of splenectomy and the removal of the primary tumour after splenectomy on the above parameters were also annotated. The following were found: 1. Splenectomy performed 8 days after B-16 melanoma tumour implantation in mice i.e. in the early period of oncogenesis, lengthened the survival of the grafted experiments, delayed tumour growth, reduced the "activity" of the tumour and caused pseudoencapsulation of the tumour by fibrous tissue. It increased, but not by a statistically significant degree (p > 0.05), the circulating levels of the IgG immunoglobulin. 2. Splenectomy performed 28 days prior to grafting of the same tumour did not affect the circulating IgG levels nor did it prolong survival; however it reduced the rate of tumour growth and pseudoencapsulation of the tumour was observed. 3. Splenectomy at the early stages of oncogenesis in combination with surgical removal of the primary tumour increased absolute and mean survival, delayed the tumour growth rate, increased the time to relapse and reduced the "activity" of the pseudoencapsulated tumour.

Animals↗
PubMed1997

The 10 years single center experience of using elderly donors for living related kidney transplantation.

The use of elderly donors has been advocated to expand the organ donor pool because of increased needs and organ shortage. The aim of the study was to analyse whether old age of donors affects the outcome of renal transplantation and the long term safety of retrieval for the donors. We present data of 335 consecutive living related kidney transplants, performed in our centre the last 10 years, where in 174 patients the donor was less than 60 years of age, while in the rest 161 patients the donor was more than 60 years of age. No statistical difference was noted in either group at the incidence of irreversible acute rejections, early acute tubular necrosis, vascular complications and patient deaths. The graft survival was 86.7%, 80.4% and 78.1% for the 3rd, the 5th and the 8th year for the younger group of donors, while it was 83.6%, 78.2% and 67.8% for the older group (p = 0.13). Patient survival of the younger group was 95.9%, 94.7% and 94.7%, while for the older was 94.4%, 92.0% and 89.2% for the 3rd, the 5th, and the 8th year post transplantation (p = 0.24). Functional rehabilitation and quality of life were good in donors and recipients of both groups. These results suggest that renal transplantation from elderly donors offers comparable results from those obtained from younger donors.

Adolescent↗
PubMed1997

[Experiences with surgical therapy of hepatic echinococcosis].

Between January 1984 and December 1990, 56 patients with hydatid liver disease were treated surgically at our Department. Diagnosis was made by using clinical criteria, serology and imaging techniques. Most frequent clinical symptom was abdominal pain or local discomfort (38 patients, 68%). Plain X-ray of the abdomen was helpful in 20 patients (36%), liver ultrasound in 53 (93%) and computerised tumorgraphy in 56 patients, (100%). The immunoelectrophoresis test of "arc 5" was sensitive in 51 patients (91%). Thirty patients (53%) underwent partial resection and omentoplasty, 17 patients (30%) underwent external drainage, two cystic resection (3%), one left lateral lobectomy (2%) and six (11%) underwent omentoplasty and T-tube insertion. Fatal complications did not occur. Four patients developed hepatic abscess (7%), three wound infection (5%), one bowel obstruction (2%) and in five instances (8%) drainage was maintained for more than three months. Of the 49 patients available for follow-up (87%), three (6%) developed recurrent disease.

Adult↗
PubMed1996

Cell senescence and a mechanism of clonal evolution leading to continuous cell proliferation, loss of heterozygosity, and tumor heterogeneity: studies on two immortal colon cancer cell lines.

Extensive karyotypic analysis was performed on early and late passages of two continuous human cell lines, SW480 and SW620, that were derived from the same colon cancer patient. We cultivated these two cell lines in vitro for a period of 24 months and periodically examined their chromosome constitution. SW480 cells, from passage 138, were injected subcutaneously into 20 nude mice. The tumors that grew in nude mice were then cultivated in vitro for several passages to compare histopathologic findings and tumor growth patterns with clonal chromosomal profiles. Despite some karyotypic diversity, the two cell lines exhibited common marker chromosomes and followed similar patterns of evolution. During subsequent passages, acquisition of new chromosomal abnormalities gave rise to sidelines with a near-diploid genome that frequently underwent endoreduplication. Genomic instability seemed to play an important role in the emergence, growth, and subsequent elimination of the heterogenous sidelines by selection, clonal expansion, and cell death by senescence. Despite continuous growth, both the cell lines occasionally showed telomeric associations and random dicentric and multicentric formations. These lesions were considered evidence of cell senescence and were related to the disappearance of particular sidelines through evolution. Successful evolutionary steps were characterized by elimination of pre-existing marker chromosomes that were subsequently replaced in the karyotype by their cytologically intact homologous chromosomes possibly after selective endoreduplication. Frequent loss of heterozygosity for the chromosomes taking part in this process is postulated. We suggest that one of the mechanisms by which cancer cells bypass senescence may be related to their potential for continuous clonal diversification.

Animals↗
PubMed1996

Cystic dilatations of the common bile duct in adults.

Cystic dilatations of the common bile duct are believed to be of congenital etiology with most cases presenting in childhood. During the last 20 years, 10 patients with cystic dilatations of the bile duct were treated in our Department. There were 5 men and 5 women with an age range of 35-81 years. Clinical presentation consisted of right hypohondrial pain, nausea, vomiting and a history of obstructive jaundice. Diagnosis was established by ultrasound, cholangiography and ERCP in most cases. According to the Todani classification system, 5 patients had type I cysts, 4 had type II and one had type III. At the time of surgery, main associated diseases were choledocholithiasis in 3 cases and cholangitis in 2 cases. One patient (type III) underwent endoscopic sphincterotomy; 4 patients underwent internal drainage and 2 of them developed mild cholangitis postoperatively; 5 patients underwent excision of the cyst and a biliary-enteric bypass and developed no main complications. Patients remained in good health during long-term follow-up. We conclude that cyst excision is the treatment of choice for adults in order to reduce postoperative morbidity and the potential risk of malignancy.

Adult↗
PubMed1993

Obstructive colonic cancer.

The records of 121 patients with obstructing cancer of the colon were reviewed. About one-third of the patients had metastatic disease at the time of operation. Primary resection and anastomosis of the intestine was performed for most cancers of the ascending or transverse colon. Hartmann's procedure was performed in most patients with cancer of the sigmoid colon and rectum. Wound infection occurred in 20 patients (16.5%) and anastomotic leakage in six (4.9%). The operative mortality rate was 14.9%. The 5-year survival rate was 13.5%. Acute colonic obstruction is associated with high morbidity and mortality. The high incidence of advanced disease, advanced age, delay in tumour excision and unprepared bowel are some of the factors resulting in the poor prognosis of these patients.

Acute Disease↗
PubMed1989

Atrial natriuretic peptide levels during and after acute cardiac tamponade in dogs.

The ability of the atrial wall to secrete atrial natriuretic peptide was studied in eight dogs during 2 h of cardiac tamponade and for 2 h after decompression of the pericardium. Cardiac tamponade was induced by instillation of 5% dextrose in water into the pericardial cavity until aortic systolic pressure was reduced by 30% to 35%. Heart rate, cardiac output and atrial, pericardial and aortic pressures were measured at 60 and 120 min of tamponade and at 5, 30, 60, 90 and 120 min after decompression. Blood samples were withdrawn at the same time for the determination of atrial natriuretic peptide and aldosterone levels. Aortic pressure decreased significantly during tamponade and increased after decompression to near control levels. Right and left atrial pressures as well as intrapericardial pressure increased significantly during tamponade and returned to control levels after decompression. The effective transmural pressure, which was reduced during tamponade, was increased significantly at 5 min after decompression. Cardiac output was significantly reduced during tamponade and returned to pretamponade levels after decompression. Over the total experimental period, no significant changes in the levels of atrial natriuretic peptide were observed, whereas aldosterone increased significantly. It is concluded that the increased atrial pressure observed during cardiac tamponade did not stimulate the secretion of atrial natriuretic peptide. Furthermore, atrial distension observed immediately after decompression was not sufficient or of long enough duration to induce measurable increases in atrial natriuretic peptide levels. Finally, the secondary hyperaldosteronism did not activate atrial natriuretic peptide secretion either during cardiac tamponade or after decompression.

Aldosterone↗
PubMed1989

[Role of cyclic AMP in gastric secretion. The secretion and mechanism of action of gastrin].

The present study involved evaluation of the role played by cyclic AMP on the secretion and mechanism of action of gastrin in man. On the basis of the results obtained, gastrin secretion induced by an excessive rise in gastric pH is accompanied by a simultaneous increase in plasma cyclic AMP concentrations (p less than 0.05) as well as a tissue cyclic AMP in the region of the fundus (p less than 0.001). By contrast, no significant change was seen regarding antropyloric AMP. As a result, it is felt that cyclic AMP does not play a direct role in the secretion of gastrin by G cells but is a mediator of the mechanism of action of gastrin in terms of the secretion of HCl by the parietal cell.

Cyclic AMP↗
PubMed1989

[Surgery of the adrenal glands in Cushing's syndrome].

Our surgical experience for the Cushing syndrome, reviewed in 23 patients. The accuracy of localizing adrenal lesions increased recently. The present study shows that, adrenal surgery, after accurate diagnosis and localisation, can be performed with low morbidity and mortality.

Adrenalectomy↗
PubMed1988

Effects of cold stress on serum lipids, lipoproteins, and the activity of lecithin:cholesterol acyltransferase in rabbits.

Effects of prolonged stress on lipid metabolism factors were studied for 9 weeks using four groups of young New Zealand rabbits. Two groups (A,B) were rendered atherosclerotic by administering 1% (w/w) cholesterol. One group (C) was subjected to cold stress together with one of the atherosclerotic groups (B); one group was used as control (N). At the end of treatment serum total cholesterol and total lipids of A and B increased significantly, while in stress group (C) a significant decrease was observed. HDL-C levels were reduced in all experimental groups. Triglycerides did not change in A, while they were reduced in both stress groups (C,B). Serum lecithin:cholesterol acyltransferase (LCAT) activity levels of B and C were decreased. Lipoprotein electrophoresis patterns showed a significant redistribution of percentage values in all experimental groups: %LDL-C increased and %VLDL-C decreased in all groups, %HDL-C declined in A and B and did not change in C. The combination of stress and atherosclerosis in rabbits elicits far greater alterations in lipid and lipoprotein profiles than stress or atherosclerosis alone. A stress and atherosclerotic diet combination may be a hazardous one in relation to CHD and atherosclerosis.

Animals↗