Histological alterations in the structure of the testis in tench (Tinca tinca) after exposure to 17 alpha-ethynylestradiol

Environmental pollution with synthetic estrogens may pose a serious threat to reproduction of aquatic wildlife species. The current study describes the effects of 17α-ethynylestradiol (EE2 ) on the structure of the testis in tench (Tinca tinca). Adult male tench were exposed to sublethal doses of EE2 (50, 100, and 500 μg/Kg t.w.) under semistatic conditions for a period of 30 days. The condition factor (CF), testicular somatic index (TSI), and histology (including a morphometric analysis) of the testis were examined. No consistent differences were observed in the CF of EE2 -exposed tench when compared with nonexposed fish. A significant decrease in TSI could only be observed at a 50 μg/Kg t.w. EE2 dose (p < 0.05) when compared with the control group. The histopathology of the testis was associated with loss of normal tubular structure with increased doses of exposure, decrease of tubule number, degeneration in Sertoli and Leydig cells, increase in necrotic testicular cells including formation of syncytia structures and, finally, a high incidence of fish with early primary oocytes at 100 and 500 μg/Kg t.w. EE2 . These results indicate that long-term exposure to EE2 may produce clear negative effects on testicular structure in tench.

Effects of cyanobacterial extracts containing anatoxin-a and of pure anatoxin-a on early developmental stages of carp

This study compares the effects of pure anatoxin-a and cyanobacterial extracts of an anatoxin-a producing strain on early stages of development of carp. Carp eggs were exposed from 2:30 h to 4 days post-fertilization to different ecologically relevant concentrations of anatoxin-a, provided as pure toxin or contained in the cyanobacterial extracts. Data on time to mortality, mortality rate, time to hatching, hatching rate, skeletal malformations rate, and larval standard length were registered until 8 days post-fertilization. At any tested concentration of anatoxin-a, the pure toxin was almost harmless to carp early stages of development, contrarily to cell extracts that were highly toxic. Only an adverse effect on the larval length was found at the highest concentration of pure toxin, while increasing concentrations of cell extracts caused increasing adverse effects in all the analyzed parameters. Anatoxin-a producing cyanobacteria should be regarded as putative modulators of aquatic ecosystems communities.

[Results of regular follow-up after removal of colorectal adenomas]

After resection of colorectal adenoma 453 patients were included in a follow-up program between 1. 1. 1980 and 30. 6. 1991. 275 patients underwent regular follow-up examinations, the primary drop-out rate was 39.2%. In the 275 participating patients 492 primary adenoma were removed. 174 patients (63.3%) had a single adenoma, while 101 patients showed multiple primary adenoma (36.7%). The average follow-up interval was 37 (+/- 28.2) months. During follow-up we found new adenoma in 105 patients (38.2%), the Kaplan-Meier estimation of the five-year-recurrence rate was 55.9% (95% confidence-interval 46.9 to 64.8%). The risk of recurrence was increased in patients with multiple primary adenoma (p = 0.003) and multivariate risk analysis showed an independent influence of histology on recurrence rate (p = 0.07). In six patients colorectal carcinoma were detected during adenoma follow-up. During regular follow-up examinations after surgical treatment for colorectal adenoma in more than 30% of all patients new colorectal polyps were detected and removed. Therefore follow-up for colorectal adenoma is effective in prevention of colorectal carcinoma. Still frequency of follow-up examinations have to be adapted to the individual risk of recurrence for each patient.

[Follow-up in stomach carcinoma]

For ten years after resection of stomach cancer patients were routinely examined to detect early asymptomatic recurrence, 96 records were analyzed, 21 patients with recurrence of cancer were found--3 local recurrence and 18 distant metastases. There was no anastomosis recurrence, 20 of these patients had clinical symptoms. About 90 percent of all recurrences were found in the first two years. After diagnosis of recurrence the one-year-survival-rate was only eight percent. We believe that the regular follow-up following resection of stomach cancer is not an effective method of detections asymptomatic curable recurrence. For this reason we recommend intensifying individual care and decreasing endoscopic or radiological examinations.

[Individual risk-related after-care in colorectal cancer?]

Efficacy of the regular follow-up program and influence on survival rate following treatment of recurrence were evaluated. 556 follow-up records of patients after resection of colorectal cancer were analysed. The primary drop-out rate was 12.4%. Recurrences were found in 26.6% (n = 128). 53.1% of recurrences were symptomatic at diagnosis of recurrence. Curative resection of recurrence was only performed in 19.5%. 46.1% were given palliative and 34.4 no specific oncologic treatment. We define efficacy as the rate of curative asymptomatic recurrence. This was 3.5% of all patients. From the curative resection of recurrence only 6 patients were free of recurrence longer than 2 years. No second resection of recurrence was possible. Different treatment of recurrence did influence the survival rate (p = 0.09). There was no difference in prognosis for asymptomatic and symptomatic recurrences (p greater than 0.8). In order to increase the efficacy of follow-up for colorectal cancer we are introducing a new concept based on individual risk factors.

[Routine gastroscopy before cholecystectomy]

We are of the opinion that the investigation of the upper gastrointestinal tract must precede an elective cholecystectomy. In a prospective study the value of preoperative oesophagogastroduodenoscopy preceding elective cholecystectomy is considered. 589 gastroscopies were performed in our endoscopy unit on 960 patients coming to elective gallbladder surgery. Only in 56% of patients we detected no abnormalities. Our plan of therapy was changed in 113 patients (11.7%). 11 patients were discharged after conservative medical therapy (1.1%), in 31 cases simultaneous procedures were performed (3.2%). After additional medical treatment 71 patients came to elective cholecystectomy (7.4%).

[Rupture of a hydatid cyst of the liver into the bile ducts evaluated by computerized tomography (author's transl)]

Case report of an cysto-biliary fistula in hydatid disease of the liver evaluated by computed tomography and endoscopic retrograde cholangiography.