Oxidation of anti-thyroid drugs and their selenium analogs by ABTS radical cation

Lactoperoxidase was previously used as a model enzyme to test the inhibitory activity of selenium analogs of anti-thyroid drugs with 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) as a substrate. Peroxidases oxidize ABTS to a metastable radical ABTS•+, which is readily reduced by many antioxidants, including thiol-containing compounds, and it has been used for decades to measure antioxidant activity in biological samples. We showed that anti-thyroid drugs 6-n-propyl-2-thiouracil, methimazole, and selenium analogs of methimazole also reduced it rapidly. This reaction may explain the anti-thyroid action of many other compounds, particularly natural antioxidants, which may reduce the oxidized form of iodine and/or tyrosyl radicals generated by thyroid peroxidase thus decreasing the production of thyroid hormones. However, influence of selenium analogs of methimazole on the rate of hydrogen peroxide consumption during oxidation of ABTS by lactoperoxidase was moderate. Direct hydrogen peroxide reduction, proposed before as their mechanism of action, cannot therefore account for the observed inhibitory effects. 1-Methylimidazole-2-selone and its diselenide were oxidized by ABTS•+ to relatively stable seleninic acid, which decomposed slowly to selenite and 1-methylimidazole. In contrast, oxidation of 1,3-dimethylimidazole-2-selone gave selenite and 1,3-dimethylimidazolium cation. Accumulation of the corresponding seleninic acid was not observed.

Inflammatory pseudotumour of urinary bladder - a rare cause of massive macroscopic haematuria

PURPOSE

Authors analyzed their experience with urinary bladder tumours. This article discusses clinical and histopathological diagnostics and treatment procedures, and follow up of patients with rare benign urinary bladder tumours.

METHODS

406 patients with bladder tumours were treated in our department between January 2000 and December 2008. 322 patients had superficial tumours and 84 had primary invasive tumours. All patients who underwent transurethral resections of these tumours were operated under general or spinal anaesthesia. The resected specimens were histologically examined in the department of Pathology.

RESULTS

399 of the 406 patients had urothelial bladder cancer, 7 patients had a histologically uncommon type of bladder tumour, one female was diagnosed with sarcomatoid bladder cancer, one patient had a histologically confirmed feochromocytoma of the urinary bladder. Two males had epidermoid carcinoma. One female had a histologically described uncommon benign pseudoneoplastic lesion, chararacteristic for endosalpingiosis. Another two patients were diagnosed with inflammatory myofibroblastic tumour of the urinary bladder. Both patients presented with gross macroscopic haematuria. Authors performed complete transurethral tumour resections, which required several sessions and the deliberation of a blocked ureter through nephrostomy in one case.

CONCLUSION

More than 98 % of all treated patients had urothelial bladder cancer in different stages and grades. Two patients had rare benign inflammatory proliferation of the bladder wall which formed large tumorous bleeding masses obstructing the ureter in one case. These types of bladder tumour could be treated conservatively with meticulous long term follow up similarly to patients with bladder cancer (Tab. 1, Fig. 4, Ref. 15). .

D-dimer, plasminogen activator inhibitor-1, prothrombin fragments and protein C - role in prothrombotic state of colorectal cancer

The relationship between malignant tumors and blood coagulation disorders is generally well known. The authors studied blood coagulation in patients with colorectal cancer and evaluated some prothrombotic markers. The authors analyzed by latex-aglutination method, ProC Global test, Asserachrom PAI-1 test and Enzygnost F 1+2 test the group of 137 patients with malignant tumor of colon and rectum, drew attention to the relationship between level of D-dimer, PAI-1, F 1+2, Protein C and the progress of malignant tumor, its localization, clinical stage, histopathology type, method of surgery considering the stapling use. Very aggressive and advanced tumors have significantly higher level of D-dimer, plasminogen activator inhibitor I (PAI-1). Prothrombotic fragments 1+2 were significantly higher by anastomosis dehiscence. Protein C level was lower in the age from sixty to seventy and in advanced clinical stage. Pre-operative surveys of D-dimer, PAI-1, prothrombotic fragments and Protein C give informations about risk of thrombosis of malignant diseases, their clinical stage and histological type. D-dimer and PAI-1 have a real clinical value and can be reliable prothrombotic marker.

[Benefits of sentinel lymph node examination in early breast carcinoma]

INTRODUCTION

Sentinel lymph node biopsy improves staging of disease, saves the axilla, and significantly reduces the risk of complications.

MATERIAL AND METHODS

The authors compare the two groups of surgical treatment of breast cancer patients--after conventional surgery with axillary exenteration with a group of patients with sentinel node biopsy using gamma probe with limited power.

RESULTS

In group of 42 patients after axillary exenteration authors observed: hematoma in 2 patients, 1 postoperative bleeding that need for surgical revision, 2 patients had paresthesia and 1 patient had lymphedema, which represents 11.5% of complications. In the group of 54 patients after limited exercise with the use of sentinel biopsy and gamma probe authors reported only one complication--an infected surgical wound seroma in the axilla (1.8% complications).

CONCLUSION

Examination of sentinel node biopsy in combination with exact measurement of gamma probe allows friendly operating performance in the axilla and significantly reduces the incidence of postoperative complications.

[Coagulation disorder and its uncommon complication in a patient with obturating sigmoid carcinoma]

AIM

The authors point to the risk of hypocoagulation by patients with colorectal carcinoma, who use warfarin.

MATERIAL AND METHODS

185 patients with colorectal cancer were examined for plattellets, prothrombin time and D-dimer.

RESULTS

Only 64 patients (35%) had haemocoagulation in the standard, 114 patients (61%) were hypercoagulable and only 7 patients (3.7%) were hypocoagulable. The authors present an interesting case report of a patient who used warfarin. This patient has ileos state by sigmoideal cancer, and in parallel a progressive intramural haematoma in the hepatic flexure of the colon.

CONCLUSION

Hypocoagulation state with an intramural haematoma of colon may be very dangerous complication for patients with colorectal cancer and ileos state. Very careful choice of surgical strategy is necessary.

Malignant tumours of colon and rectum from the blood clotting view

OBJECTIVES

The relationship between malignant tumours and blood coagulation disorders is generally well known.

BACKGROUND

The authors notice blood coagulation in patients with colorectal cancer and evaluate prothrombotic markers.

METHODS

The authors analyzed a group of 137 patients with malignant tumour of colon and rectum, drew attention to the relationship between level of D-dimer, PAI-1, F 1+2, Protein C and the progress of malignant tumour, its localization, clinical stage, histopathology type, method of surgery considering the stapling use.

RESULTS

Very aggressive and advance tumours have high level of D dimer, plasminogen activator inhibitor I (PAI-1). Prothrombotic fragments 1+2 were significantly higher by anastomotic dehiscence. Protein C level was lower by age from sixty to seventy and in advanced clinical stage.

CONCLUSION

Pre-operative surveys of D dimer, PAI-1, prothrombotic fragments and Protein C give informations abaout risk of thrombosis, far gone of malignant diseases, they clinical stage and histological type. D dimer and PAI-1 have the most clinical value (Fig. 5, Ref. 11).

Ileus, pregnancy or leiomyoma? A case of a large intraabdominal tumor

OBJECTIVE

Authors evaluate a case of an extremely large leiomyoma, its symptomatology, diagnosis and surgical treatment. They present the possible peroperative complications and emphasize the necessity of the interdisciplinary approach.

METHODS

The set of patients consists of 21 patients with leiomyomas of various localizations. All patients were operated by means of conventional operation. The material was sent for classical bioptic examination with the use of immuno-histochemical analysis.

RESULTS

Unlike found in literature, the most common appearance of leiomyoma in our set of patients was on small bowel, namely 10 of 21 patients had tumors in this localization. Furthermore there were three tumors of gynecological origin. Two of them had acute abdominal disease (AAD) while in these cases, ileus was a reason for urgent operations. In all three gynecological cases it was difficult to diagnose preoperatively the origin of tumors. In one patient, the preparation led to partial iatrogenic lesion of left ureter which was subsequently treated with primary suture. The authors describe zero mortality.

CONCLUSION

Despite the relatively simple diagnosis of leiomyomas, in some cases of extreme size of the tumor combined with its localization in the small pelvis makes it difficult to distinguish it from other mesenchymal tumors. In order eliminate the peroperative complications it is possible to introduce a urethral catheter and to set up a multidisciplinary operation team to achieve combined experience (Fig. 5, Ref. 14).