PubMed Health⌕ Search

Biomedical subjects

G Baretton

Publications and source records attributed to G Baretton.

At least 55 records · Page 3Linked to original sources
PubMed1993

[Teratoma of the umbilical cord. Case report with literature review].

A rare case of teratoma of the umbilical cord is reported. It is differentiated from acardius amorphus and compared with the nine cases reported in the literature since the first description in 1878. The clinical consequences for pregnancy of the tumour's influence on the circulation are discussed. For the first time, non-radioactive in situ hybridization of the interphase nucleus was performed in a teratoma of the umbilical cord. The results are presented and different histogenetic pathways, e.g. parthenogenetic origin of the teratoma, are debated.

Cell Transformation, Neoplastic↗
PubMed1993

Endothelial denudation in HHL-rabbit aortas.

The purpose of this study has been to develop a rabbit model for the assessment and follow up of angioplastic techniques which would be comparable to human arteriosclerosis. Segments of the abdominal aortas of 10 homozygous Heritable Hyperlipidemic rabbits were treated with 2 endothelial denudation procedures and collected at sacrifice after 1 week, 1 month, 2 or 3 months. Nondenuded segments of the 3 month group were taken as native controls. All sections were stained with hematoxilin/eosin and Elastica van Gieson. Pronounced intimal thickening with fibrosis, sometimes with atheromatosis developed after 1, 2, and 3 months. After 2 months calcium deposits and after 3 months frayed inner elastic membranes were found. The control segments revealed a lesser pathogenic expression with intact inner elastic membranes. In conclusion, a substantial increase in the pathogenic expression or the development of stenoses could not be obtained by 2 endothelial denudation procedures at the age of about 5 months.

Animals↗
PubMed1993

Temperature controlled angioplasty (preliminary results in heritable hyperlipidemic rabbits).

The purpose of this investigation has been to demonstrate the safety of temperature controlled angioplasty (TCA) with a coaxial heating element, particularly during heat application, and to ascertain the short- and long-term arterial tissue response in 7 month old homozygous Heritable Hyperlipidemic rabbits. In 7 animals, a defined segment of the abdominal aorta was treated with TCA for 40 seconds at 175 degrees C, and 2 animals served as untreated controls. At sacrifice, 1 day, 1 and 2 weeks after TCA, in one animal each a coagulation necrosis with condensation of elastic fibers was found. One year later, 1 of 2 animals revealed irregularly structured elastic fibers combined with only minor atherosclerotic lesions. Treated segments of the second animal and of the 2 remaining animals 2 years after TCA did not appear to differ from the control segments. In conclusion, the TCA never resulted in perforation or carbonization or in adhesion of the heating element to the vascular wall, representing a safe angioplastic technique.

Angioplasty↗
PubMed1992

Influence of dietary iron overload on cell proliferation and intestinal tumorigenesis in mice.

Iron-enriched diets caused an increase of tumor rate in two models of dimethylhydrazine(DMH)-induced colon tumorigenesis in mice. The effect was independent of the time the iron-diet was fed, i.e. during DMH-treatment or following the DMH-treatment period. The increase of tumor rate depended on the iron concentration in the diet (0.5-3.5%). The concentration-dependent iron accumulation in the colonic mucosa of mice was paralleled by increments of malonaldehyde contents indicating lipid peroxidation, another factor known to be involved in tumor development. It is suggested that iron exerts cocarcinogenic activity in the DMH-model by stimulating cell proliferation and inducing oxidative stress in the colonic mucosa. This effect of iron is independent of the time of tumor-initiation by DMH, as it is also observed in the period of tumor-promotion/progression after DMH-treatment.

Animals↗
PubMed1992

[Therapy of splenic injuries by freezing and fibrin gluing. Animal experiment study].

The goal of this investigation was to improve the reliability of intraoperative and postoperative hemostasis and to observe the healing process after using a combined technique of tissue freezing followed by the application of collagen fleece and fibrin glue for the treatment of splenic ruptures. Grade II lesions were inflicted on the spleens of 15 swine. The bleeding wounds were frozen for 1 min at -60 degrees C using a cryosurgical device. Immediately afterwards the frozen lesions were covered with fibrin glue and collagen fleece and kept under slight compression. In every case complete hemostasis was achieved intraoperatively. The spleens of three animals each time were collected for gross and microscopic examination after 2 days and 1, 2, 5, and 6 weeks. A visceroperitoneal adhesion was observed in only one spleen, U-shaped viscerovisceral adhesions in five spleens. Superficial coagulation necroses could be detected microscopically only after 2 days and 1 week. Organization of the wounds, indicated by granulation tissue which contained siderophages, started in the 2nd week. There was distinct formation of collagen fibers after 5 and 6 weeks; only a residue of the collagen fleece was visible and the surplus fibrin glue was encapsulated. With this combined technique complete and safe hemostasis and a good subsequent healing process was achieved.

Animals↗
PubMed1992

[Bullous poikilodermatitic amyloidosis of the skin with junctional bulla development in IgG light chain plasmacytoma of the lambda type. Histology, immunohistology and electron microscopy].

A 75-year-old patient presented with bullae, poilokilodermatic skin and nail dystrophy as signs of systemic amyloidosis 1 year before an IgG myeloma of the lambda type was diagnosed. The skin lesions appeared at mechanically irritated locations on the trunk and at the tensor sites of the extremities. Histology showed a subepidermal blister and necrotic keratinocytes in the epidermis. There were amyloid deposits in the papillary dermis perivascular, and in the deep dermis around eccrine glands and in arrectores pilorum muscles. Polyclonal antibodies allowed classification of the deposits as amyloid composed of lambda light-chain immunoglobulins. Electron microscopy revealed globoid deposits of non-branching filaments typical of amyloid. The blister was formed at the level of the lamina lucida, with the lamina densa at the base of the bottom of the bulla. So far, junctional blister formation in bullous amyloidosis of the skin has been described only once. Our case is the second report of this blister type, and to our knowledge the first published report of a junctional blister in myeloma-associated systemic amyloidosis.

Actin Cytoskeleton↗
PubMed1992

[Expression of induced atherosclerosis in the rabbit model].

Atherosclerosis in rabbits was induced by administering a 2% cholesterol diet and additional endothelial denudation of the aorta and iliac artery as a model for vascular surgery. In addition, the serum cholesterol-, serum triglyceride-, and HDL-cholesterol values were examined. After 22 weeks the intima and most often the media showed atheromatosis and fibrosis, in most of the arteries with intimal necroses. All arteries developed marked to pronounced stenoses, calcium deposits were only observed in single cases. The intensity of the arterial lesions was found to be similar to the appearance of human atherosclerosis.

Animals↗
PubMed1991

[Kimura disease with minimally proliferative glomerulonephritis].

A 45-year-old Turk had a year ago noticed a submandibular and a retroauricular node-like swelling, about 2 cm in diameter each, firm and freely mobile. During the preceding two months he had polydipsia and polyuria. Recently he developed a nephrotic syndrome with lower-leg oedema and proteinuria (14 g albumin in 24-hour urine). The concentrations of IgE (250 IE/ml) and IgA (745 mg/dl) were raised, and there was eosinophilia of 14%. Renal needle biopsy revealed glomerulonephritis with minimal proliferation. Excision of part of the nodular tumour revealed histologically the typical signs of Kimura's disease (eosinophilic follicular lymphadenitis of the skin; subcutaneous angiolymphoid hyperplasia with eosinophilia). During treatment with prednisolone, 20 mg daily by mouth, the clinical and biochemical findings regressed within two weeks. But eight weeks later, after dose reduction to 10 mg daily, the nephrotic syndrome recurred so that the dosage had to be increased again to 20 mg prednisolone daily. On this treatment the patient has now been symptom-free for six months. This case demonstrates the unusual association of Kimura's disease with minimally proliferative glomerulonephritis.

Angiolymphoid Hyperplasia with Eosinophilia↗
PubMed1991

DNA-ploidy and survival in gastric carcinomas: a flow-cytometric study.

In 125 gastric carcinomas the nuclear DNA content was determined by flow cytometry from formalin-fixed and paraffin-embedded tissue of surgical specimens. The carcinomas were of intestinal or mixed type (85), and diffuse type (40). DNA-aneuploidy was found in 46% of the intestinal type and in 42% of the mixed type, but only in 15% of the diffuse-type carcinomas (P less than 0.01). The total rate of DNA-aneuploidy was 34%. Carcinomas localized in the cardia were more frequently DNA-aneuploid than tumours in other localizations (P less than 0.01). DNA-aneuploid carcinomas had metastasized more frequently to regional lymph nodes (P less than 0.05) whereas no correlations with tumour stage and cytological/histological grade were detected. In 94 patients follow-up data were available. DNA-aneuploidy was associated with a statistically significant poorer prognosis when compared to DNA-diploid tumours only in advanced gastric carcinomas with lymph node metastases (P = 0.0488) and in the subgroup of advanced intestinal and mixed-type tumours (P = 0.0289).

Adenocarcinoma↗
PubMed1991

Intratumoural heterogeneity of nuclear DNA-content and proliferation in clear cell type carcinomas of the kidney.

Clear celled renal carcinomas (n = 37) were investigated by flow cytometry for intratumoural heterogeneity in DNA-ploidy and proliferation (S-phase rate). Using gross sections of the tumours, 178 regions of interest were selected and excised from the paraffin blocks. Of the tumours examined 30% (n = 11) were DNA-diploid and 70% (n = 26) were DNA-aneuploid. In six tumours (16%) homogenous DNA-aneuploidy was detected, and in 20 others (54%) there was intratumoural heterogeneity of DNA-content with a blend of either DNA-diploid and DNA-aneuploid regions (n = 16; 43%) or different aneuploid stemlines (n = 4; 11%). DNA-aneuploidy was present both in areas of the tumours composed of clear cells and in regions containing cells with cytoplasmatic eosinophilia. However, DNA-aneuploidy was correlated in a statistically highly significant manner with the degree of cytoplasmatic eosinophilia and the nuclear grading of tumour cells. The results were confirmed by comparative analysis of fresh-frozen and paraffin-embedded material. The DNA-aneuploid portions of the tumours, and the regions with increased cytoplasmatic eosinophilia, proved to have significantly higher S-phase rates than DNA-diploid and clear tumour cells. These results agreed well with the immunohistochemically determined percentage of Ki-67 (proliferation associated)-antigen positive cells. Our findings indicate that tumour cells with increased eosinophilia in renal cell carcinomas are distinct from real clear cells by virtue of their higher rates of aneuploidy and proliferative activity. These cells might therefore be regarded as a subclass with a more aggressive biological behaviour.

Adenocarcinoma↗
PubMed1991

Flow-cytometric analysis of the DNA-content in paraffin-embedded tissue from colorectal carcinomas and its prognostic significance.

The nuclear DNA content of 163 colorectal carcinomas was determined by flow-cytometry (FCM) on formalin-fixed, paraffin-embedded tissue. DNA-aneuploidy was found in 97 cases (59.5%), in which no statistically significant correlations with sex, mean age, tumour stage (Dukes and pTNM) and tumour grade were noted. The frequency of aneuploidy was significantly higher in patients less than 70 years of age (p less than 0.01) and in tumours localized in the left colon and rectum (p less than 0.002), irrespective of their stage. The tumours in which different areas could be analysed (n = 80) showed a heterogeneous DNA-ploidy pattern in 18%. Comparison of the DNA content in primary tumours and in lymph node metastases (n = 49) showed a difference in DNA-ploidy in 38% of the DNA-aneuploid tumours, but in only 6% of the DNA-diploid carcinomas (p less than 0.02). DNA-aneuploid carcinomas tended to show a higher rate of local recurrence and were associated with an unfavourable prognosis (p = 0.04) in those patients in which complete resection of their tumours was possible (n = 72). The significantly higher mortality of patients with DNA-aneuploid carcinomas of stage pT3, as well as those with Dukes stage A and B tumours indicates that DNA-aneuploidy may be a stage-independent additional risk factor in colorectal cancer.

Aged↗
PubMed1991

Effects of hyperthermia and/or hyperglycemia on pH and pO2 in well oxygenated xenotransplanted human sarcoma.

The heat-induced interdependent changes of tumor blood flow, pO2, and pH decisively influence the therapeutic effect of hyperthermia (HT). This fact has induced us to determine simultaneously the frequency distribution of local pO2 values and the intratumoral pH in a xenotransplanted human sarcoma cell line at a normal blood glucose level and under hyperglycemic conditions before, during, and after HT. Two groups, one of 10 and one of 9 congenitally athymic nude rats with a subcutaneously implanted S117 human sarcoma into the right hind paw (mean tumor volume 5.3 cm3) were treated with local waterbath HT (tumor temperature 43 degrees C, 1 hr) alone or in combination with i.p. glucose injections (6 g/kg, 2 hr before the onset of HT). Tumor oxygenation remained improved throughout HT. Tumor pH did not decrease during HT. Hyperglycemia alone elicited a decrease of intratumoral pH and pO2, probably mainly due to hemoconcentration. The additional warming of the tumors (43 degrees C) during hyperglycaemia did not further decrease pO2 and pH. Silver stained sections of the tumors showed only a few very small necrotic areas, even in tumors of volumes up to 8 cm3. Our results indicate a well oxygenated tumor. In contrast to most tumors studied so far, hyperthermia in this tumor induces not only an initial increase of oxygenation but a lasting elevation of mean tumor pO2 for the duration of HT (up to 60 min).

Animals↗
PubMed1990

[Comparison of flow cytometric, static cytometry and tumor cytogenetic investigation results human renal cell carcinomas].

Published data about the frequency of DNA-aneuploidy of renal cell tumours show a great variation. The own study was performed to clarify whether this fact is due to methodological discrepancies or to intratumoural heterogeneity of DNA ploidy. The comparison of DNA ploidy assessed by flow cytometry (fresh and paraffin-embedded tissue) and static cytometry (paraffin-embedded tissue) in equivalent tumour regions showed identical results. 71% of clear cell renal carcinomas showed intratumoural heterogeneity of DNA ploidy. In 55% there was either a combination of diploid and aneuploid stem lines and/or a combination of different aneuploid stem lines ("heterogenous aneuploidy"). The rate of aneuploidy was found to be higher with increasing cytoplasmic eosinophilia of the clear cell renal carcinoma cells. Studies which address the prognostic significance of DNA ploidy of renal carcinomas should specifically investigate on the significance of heterogenous aneuploidy for prognosis.

Aneuploidy↗
PubMed1990

[Retrospective flow-cytometric analysis of the DNA content in colorectal carcinomas and the test of the prognostic significance of DNA ploidy].

The nuclear DNA content of 163 colorectal carcinomas was determined by flow-cytometry (FCM) on formalin-fixed and paraffin-embedded tissue. DNA-aneuploidy was found in 97 cases (59.5%), without correlation to sex, mean age, tumor-stage (DUKES and pTNM) and grading. The frequency of aneuploidy was statistically significantly higher in patients younger than 70 years of age (p less than 0.01) and in tumors localized in the left colon and rectum (p less than 0.002). The tumors in which different areas could be analyzed (n = 80) showed a heterogeneous DNA-ploidy pattern in 18%. The comparison of DNA-content in primaries and in lymph-node metastases (n = 49) resulted in a difference of DNA-ploidy in 38% of the DNA-aneuploid tumors, but only in 6% of the DNA-diploid carcinomas (p less than 0.02). Carcinomas with DNA-aneuploidy showed a trend to a higher rate of loco-regional recurrences, a higher S-phase fraction (13.5% +/- 5.9 vs. 8.1 +/- 7.0), and proved to be associated with a poorer prognosis (p = 0.04). The statistically significantly higher mortality of patients with DNA-aneuploid carcinomas in DUKES A and B stages indicates that DNA-aneuploidy could perhaps be regarded as a stage-independent additional risk factor.

Aged↗
PubMed1990

[Ultrasound-controlled fine needle biopsy of pathologic space occupying lesions in the head and neck area].

We report 121 fine-needle aspiration biopsies of tumours and lymph nodes of the head and neck guided by ultrasound. The average minimal diameter of the lesions was 1.2 cm; the smallest lymph node was adjacent to the carotid artery and had a diameter of 0.4 cm. There were no complications. Of the cytological results 96% were confirmed by histology or by the subsequent clinical course.

Biopsy, Needle↗