Biomedical subjects

G Baretton

Publications and source records attributed to G Baretton.

66 records · Page 4Linked to original sources

PubMed1989

[Primary gastrointestinal lymphomas].

From 1980 up to 1987 seven patients with primary gastrointestinal lymphoma were treated at the surgical department of the Medical University of Lübeck; six of them were women. The mean age was 73.3 years. The tumors were located in the stomach (4), the large bowel (2) and the small intestine (1), representing disease at Ann-Arbor-stage IE (5) and IIE (2). All patients underwent primary surgery, except one due to his bad general conditions. Irradiation-therapy followed in one case, chemotherapy in two cases when relapse of disease was revealed. Three patients are still alive (0.8 to 6.8 years) without evidence of recurrent lymphoma. The success of surgery as a curative treatment is closely related to the stage of disease; both are important factors influencing prognosis. Surgery is still necessary for diagnosis, tumor-staging and prevention of regional complications as bleeding or perforation, especially when conservative therapy is performed.

Adenocarcinoma↗

PubMed1989

[Percutaneous transhepatic laser lithotripsy of gallstones--results of animal experiments].

Since laserinduced shock wave lithotripsy of gallstones is possible for treatment of common bile duct stones, the percutaneous transhepatic laserlithotripsy of stones in the gallbladder is examined in an animal study. In 8 animal experiments it could be shown that puncture of the gallbladder, dilatation of the working channel, (laserinduced) shock wave lithotripsy, removal of the fragments and the instruments are possible in one session. Neither when performing simple closure of the wound by suture nor by fibrinsealing severe side-effects could be recognized. After laserlithotripsy ablation of epithelium and hematomas can be observed, which are restituted within one month. The experiments show that in organ-saving shockwave lithotripsy there is no need for waiting for the development of a fistula and the percutaneous approach can be simplified.

Animals↗

PubMed1989

A new system for cutting brain tissue preserving vessels: water jet cutting.

The water jet cutting system allows transaction and dissection of biological structures with little bleeding. Structures of higher tissue rigidity remain unchanged while softer tissues are mechanically dissected. In brain tissue, all vessels larger than 20 microns are left intact after the passage of the jet stream with a pressure of up to 5 bar, and therefore vessels can be isolated selectively from the surrounding tissue. Oedema is present adjacent to the cut and no increase of temperature occurs.

Animals↗

PubMed1988

Inhibition of halothane-induced lipid peroxidation by misoprostol without hepatoprotection.

In mice, the synthetic prostaglandin derivative misoprostol failed to protect against liver damage induced by acetaminophen, carbon terachloride,1,1-dichloroethylene or thioacetamide. In rats, misoprostol (20-100 micrograms/kg p.o.) markedly reduced early increments of plasma enzyme activities (glutamate-pyruvate-transaminase, GPT; sorbitol dehydrogenase, SDH) in a model of halothane-induced liver injury; the most effective dose in this respect (20 micrograms/kg) significantly depressed halothane-induced ethane exhalation indicating in vivo lipid peroxidation. Repeated treatment with misoprostol (20 micrograms/kg p.o.) still diminished halothane-induced elevations of enzyme activities over 48 h, but failed to prove hepatoprotection by histomorphological examinations. It is concluded that the antiperoxidative properties of misoprostol are not paralleled by an hepatoprotection, which was indicated by significant reductions of liver-specific plasma enzyme activities, but not confirmed by the morphological picture.

Acetaminophen↗

PubMed1988

Dietary iron enhances the tumor rate in dimethylhydrazine-induced colon carcinogenesis in mice.

Treatment of male mice with 20 mg/kg dimethylhydrazine (DMH) s.c. for 10 weeks caused a mean tumour rate of 3.5 after 20 weeks. Dietary iron (3.5% Fefumarate for 10 weeks) enhanced the mean tumour rate to 13.9. All tumours detected were localized exclusively in the distal colon and rectum. The iron load caused a 6.5-fold increase in the mucosal Fe-concentration in the proximal as well as distal colon. DMH-demethylase activity was not influenced by iron and did not differ between proximal and distal segments. Cytosolic alcohol dehydrogenase (ADH) activity was also not altered by iron, but was 3.3-fold higher in the distal colon and rectum as compared to proximal segments; this might explain the DMH-induced tumorigenesis in the distal colon only. It is suggested that iron ions might evoke cocarcinogenic activity by a stimulation of cell proliferation.

Alcohol Dehydrogenase↗

PubMed1988

Functional and histological restitution in the urinary tract after Nd:YAG laser coagulation.

Current development in endourologic equipment has made possible the endoscopic application of the Nd:YAG laser in the treatment of urothelial tumors of the whole urinary tract. The clinical results are rather promising. We controlled with various methods the healing processes of 14 rabbit ureters after Nd:YAG laser treatment as to morphological repair and physiological function. The ureters were irradiated transrenally with an energy of 60 J coagulating all wall layers. Healing of the laser lesions nearly to normal in all animals was observed 4 to 6 weeks after treatment. The prevailing histological and physiological changes in the ureter are extremely slight and do not disturb the normal ureteral function. The results show the complete healing process of the ureter after laser coagulation and make the application of Nd:YAG laser in the upper urinary tract much more predictable.

Animals↗

PubMedDate not supplied

Jet-cutting supported by high frequency current: new technique for hepatic surgery.

To reduce blood loss incurred during liver resection, techniques that separate vessels from liver parenchyma, such as the CUSA or the jet-cutter, are in clinical use. By conducting high frequency current through the jet beam using hypertonic NaCl cutting solution, we developed a new method enabling simultaneous coagulation during selective cutting. In this study we examined the effects of this method on liver resection in a rabbit model. With the three techniques-jet-cutting, CUSA, and high frequency-supported jet-cutting (HF-jet)-we performed liver resection of the ventral lobe in six animals per group. We compared velocity of resection, blood loss, tissue trauma, selectivity (number of isolated vessels per area), electrolytes, and vital signs. Histopathology was carried out with the resectate and after 7 days with the remaining liver. Velocity of resection procedure and selectivity were significantly reduced in the HF-jet group. Histopathology showed coagulated vessels and a deeper zone of necrosis. Accordingly, the liver enzymes transiently showed distinctly higher values in the HF-jet group. Electrolyte disturbances or differences of vital signs could not be detected. Transferring our results to patient care we expect that with major resections the hilus clamping time, blood loss, and number of blood transfusions can be reduced. In our opinion the additional application of high frequency through the jet beam is a helpful improvement of the jet-cutter.

Animals↗

PubMedDate not supplied

[Midterm results after treatment of liposarcoma in the extremities].

PURPOSE: In this retrospective analysis, survival time, local recurrence and rate of metastasis were appraised in patients with primary liposarcoma of the extremities depending upon the applied primary and adjuvant therapy procedures. Furthermore, we compared the representativity of histological results of the biopsy with the final histology of the resected tumour. MATERIAL AND METHOD: Between 1990 and 1998, 27 patients were surgically treated who suffered from a primary liposarcoma of the extremities. At the mean follow-up time of 62.4 months (39-141 months) postoperative survival rate, rate of metastasis and local recurrence were determined. The results were analysed with regard to intraoperative resection distance, tumour size and localisation as well as histological classification of previous biopsy and finally resected tumour. The influence of radiotherapy on the results was also determined. RESULTS: In 5 patients (18.5%) the amputation and in 22 cases (81.5%) the limb sparing resection of the liposarcoma was performed. 6 patients underwent a marginal resection and one patient an intralesional resection. At follow-up we observed a local recurrence rate of 22.2% (n = 6) and a survival rate of 74.1%. 18.5% of the patients had metastases. After adjuvant radiotherapy three patients (50%) showed local recurrence after marginal resection. In only 8 cases (29.6%) the results of primary biopsy and final tumour classification (entity, subtype and grading) were identical. CONCLUSION: The development of metastases (often pulmonary) and local recurrences even after long tumour-free interval makes adequate follow-up investigations mandatory in liposarcoma patients. With regard to the problems in assessing liposarcoma biopsies, MRI-orientated biopsies from several tumour areas via one biopsy approach are recommended.

Adult↗

PubMedDate not supplied

[Experimental results of cartilage abrasion with an excimer laser. Histologic and electron microscopy studies].

Experiments carried out with cadaver cartilage from the tibiaplateau were performed using an excimer-laser to demonstrate its use for cartilage removal. Laser applications resulted in a cartilage ablation depending on energy density and the number of applied pulses. Observations made using scanning electron-microscopy showed the influence of the pulse rate on the surface structure. Transmission-electron-microscopical investigation showed the existence of a superficially altered layer with a depth of approx. 6 microns. On the basis of the results obtained, the conclusion can be reached that application of excimer-lasers for cartilage removal in a view of future endoscopic surgery could become a valuable alternative to the existing methods in the therapy of osteoarthritis.

Cartilage, Articular↗

PubMedDate not supplied

Myomectomy as a pregnancy-preserving option in the carefully selected patient.

OBJECTIVES: To present the indications for myomectomy during pregnancy and to discuss complications possibly related and unrelated to the procedure. METHOD AND RESULTS: A 33-year-old patient at 18 weeks of gestation underwent removal of a 1,570-gram symptomatic fundic myoma. Histologically the patient had a leiomyomatous neoplasm of uncertain malignant potential. The pregnancy was continued under sequential observation with magnetic resonance imaging and ultrasound. At 36 weeks of gestation a healthy girl with an upper extremity limb defect was born via cesarean section. Follow-up of the mother and the child was uneventful. CONCLUSIONS: Certain known risk factors in pregnant women with myomas can predispose to complications during pregnancy. Women with such risk factors or women who have failed medical therapy should be offered the option of undergoing myomectomy as a pregnancy-preserving procedure.

Adult↗

PubMedDate not supplied

Chest wall hamartoma in infancy: a case report with immunohistochemical analysis of various interstitial collagen types.

We present one case of a chest wall hamartoma diagnosed in a 4-week-old boy. This entity is an extremely rare but characteristic congenital malformation of the ribs in infancy. To avoid maltreatment, it has to be distinguished from benign and malignant neoplasms on the basis of distinct histological features presented here. The immunohistochemical localization of various collagen types supports the notion of the hamartomatous nature of this lesion.

Collagen↗

PubMedDate not supplied

Experimental salvage of the spleen. A combined technique of cryosurgery and tissue sealant.

The goal of this investigation has been to improve the safety of intra- and post-operative haemostasis in splenic lesions by a combined technique of tissue freezing followed by the application of collagen fleece and fibrin glue in an animal study. The progression of healing was observed after different periods of time. Grade II lesions were set on the spleens of 15 pigs. The wounds were frozen for 1 m at -60 degrees C with a cryosurgical probe and afterwards sealed with fibrin glue and collagen fleece. In every case, complete haemostasis was achieved intraoperatively. The spleens of 3 animals each were examined microscopically after 2 days, 1, 2, 5 and 6 weeks, respectively. A visceroperitoneal adhesion was observed in only 1 spleen and u-shaped viscerovisceral adhesions in 5 spleens. Superficial coagulation necroses were observed only in specimens removed after 2 days and 1 week, respectively. Complete and safe haemostasis followed by acceptable subsequent healing was achieved using this combined technique.

Animals↗