Ischemia-reperfusion injury of rabbit ovary and protective effect of trapidil: an experimental study.

We aimed to detect the protective effect of trapidil in ischemia-reperfusion (IR) injury due to ovarian torsion and detorsion. Thirty-two pubertal New Zealand albino rabbits were used. Adnexal torsion was created by rotating the left adnexa including the tubal and ovarian vessels in a 360 degrees clockwise direction. Adnexal detorsion was done by untwisting the adnexa. In the IR group, left oopherectomy was performed after 3 h of adnexal torsion and 3 h of adnexal detorsion. In the study group, a 3-h adnexal torsion was performed and trapidil was administered intraperitoneally as a single dose of 40 mg/kg, 1 h before detorsion. The left oopherectomy was performed after a 3-h adnexal detorsion. In the sham group, sham operation was performed followed by left oopherectomy. In the control group, normal ovarian tissue was evaluated. Catalase, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) levels of ovarian tissue were determined for each group. The values of SOD and GSH-Px activities in the IR group were significantly decreased (P < 0.05). In addition, the MDA level was significantly higher in the IR group (P < 0.01). The trapidil-administered group showed significant increase in the levels of GSH-Px (P < 0.05), catalase (P < 0.05), SOD (P < 0.05), and decreased MDA levels (P < 0.05) compared to those in the IR group. The study has shown that trapidil treatment prevents ischemia induced oxidative damage in the ovarian tissues of rabbits.

Oligonucleotide conjugate GRN163L targeting human telomerase as potential anticancer and antimetastatic agent.

Telomerase is one of the key enzymes responsible for the proliferative immortality of the majority of cancer cells. We recently introduced a new telomerase inhibitor, a 13-mer oligonucleotide N3' --> P5'-thio-phosphoramidate lipid conjugate, designated as GRN163L. This compound inhibits telomerase activity in various tumor cell lines with IC(50) values of 3-300 nM without any cellular uptake enhancers. GRN163L demonstrated potent and sequence specific anti-cancer activity in vivo in multiple animal models. This compound was able to significantly affect not only the growth of primary tumors, but also the spread and proliferation of metastases. GRN163L is currently in Phase I and Phase I/II clinical studies in patients with solid tumors and CLL, respectively.

Telomerase activity in diagnosis of bladder cancer.

OBJECTIVE: Telomerase is an enzyme that can reconstitute the ends of chromosomes after cell division and thus circumvent the damage that occurs in normal adult somatic cells during successive mitotic cycles. Immortal cells have short but stable chromosomes and increased telomerase activity. Transitional cell carcinoma (TCC) has only a few useful markers of diagnostic or prognostic importance. The objectives of this study were to determine whether there was a correlation between telomerase activities and the grade or stage of TCC and whether the activity of the enzyme could serve as a biochemical marker of this tumor. MATERIAL AND METHODS: Telomerase activity was determined by examining, using a polymerase chain reaction-based assay designed using the telomeric repeat amplification protocol (TRAP), urine cell pellets obtained from 42 bladder cancer patients, 18 patients with primary hematuria, 19 patients with benign urologic disease, 14 patients with urologic malignancies other than TCC and 20 healthy volunteers. RESULTS: Telomerase activity was found in 24/31 patients with bladder tumors (77.4% sensitivity) and in 5/77 patients without tumors (93.5% specificity). No correlation was found between telomerase activity and the grade or stage of the tumor. Although none of the urine cell pellets obtained from the 20 healthy volunteers demonstrated telomerase activity, positive telomerase activity was found in two subjects in the benign urologic disease group and in three subjects in the other urologic malignancy group. It was demonstrated that gross hematuria was the cause of false-negative results in six of the nine patients (66.7%). but washing the pellets four times and diluting them before the TRAP assay solved this problem. CONCLUSION: These results indicate that telomerase activity may be a promising marker for TCC but the technical aspects of the technique must be improved before it is used in routine clinical practice as a standard method. False-negative results obtained using gross hematuric urine should be carefully reevaluated and cell pellets should be washed again and diluted before analysis.

Detection of telomerase activity in bronchial lavage as an adjunct to cytological diagnosis in lung cancer.

OBJECTIVE: Definitive diagnosis of lung cancer with conventional methods may sometimes be difficult in clinical practice. Telomerase is a ribonucleoprotein DNA polymerase that maintains the telomeric region of chromosomes during successive rounds of cell division. Telomerase activity in body cavity fluids has been advocated to be a potential diagnostic marker for malignancy. We investigated the diagnostic value of telomerase activity in bronchial lavage samples of patients undergoing diagnosis of lung cancer. METHODS: A total of 29 bronchial lavage samples were collected from patients in whom the diagnosis was confirmed with cytological and/or histological examinations. Patients were classified as lung cancer patients (Group 1, n = 22) and patients with benign disease (Group 2, n = 7). Telomerase activity was determined with polymerase chain reaction-based TRAP (The telomeric repeat amplification protocol) assay. RESULTS: Cytological examination was diagnostic in 12 (54.5%) of 22 patients in Group 1, and in all seven patients of Group 2 (P = 0.063). Telomerase activity was positive in 16 (72.7%) of Group 1 patients, while it was positive in only 1 (14.3%) sample of a lung abscess in Group 2 (P = 0.011). The sensitivity rate of cytological examination when combined with telomerase activity (81.8%) was significantly greater than that of cytological examination alone (54.5%) (P = 0.031). The sensitivity and specificity of telomerase activity were 72.7 and 85.7%, respectively. Telomerase activity had a positive predictive value as 0.94 and negative predictive value as 0.50. Diagnostic accuracy of telomerase activity was 75.8%. CONCLUSION: Telomerase activity in bronchial lavage is a highly sensitive diagnostic biomarker for malignancy and a potential complementary diagnostic technique to cytological examination in the diagnosis of lung cancer.

The assessment of pancreatic exocrine function by bentiromide test in patients with chronic portal vein thrombosis.

INTRODUCTION: It has been noted in the literature that cavernous transformation of the portal vein (CTPV) can cause pancreatic duct atrophy, probably by enhanced collateral formation, but the clinical significance of this has not been established. AIMS: To evaluate whether CTPV affects the pancreatic exocrine functions. METHODOLOGY: Eighteen patients with CTPV were identified and prospectively studied. In these cases, despite a full clinical, biochemical, radiologic, and hematological evaluation, we found no etiologic factor for thrombosis in the portal vein (PV). All patients underwent a detailed evaluation for pancreatic morphology and pancreatic exocrine functions. In all cases, abdominal Doppler ultrasonography (US), abdominal spiral computed tomography (CT), and endoscopic retrograde cholangiopancreatography (ERCP) were performed for evaluation of pancreatic morphology. For the purpose of this study, serial biochemical tests, including measurement of serum amylase, pancreatic amylase, lipase, glucose, calcium, and lipids, were performed every 3 months. All 18 patients also underwent a bentiromide test to determine whether there was any exocrine pancreatic insufficiency. The findings were compared with those for 20 healthy control subjects and reference controls. RESULTS: For all 18 patients with idiopathic CTPV and all controls, ERCP was performed successfully. The pancreatic duct was determined to be smaller than in control subjects and in a reference control group ( < 0.05). In this group serum pancreatic amylase, alkaline phosphatase, and direct bilirubin levels were found to be higher than in controls, and statistically important differences between the two groups ( < 0.05) were documented. In all 18 subjects the bentiromide test was well tolerated and was performed successfully. For 15 of them (83%), we found that urinary excretion of para-amino benzoic acid (PABA) was significantly less than in control subjects and the reference control group ( < 0.05). CONCLUSION: Pancreatic duct atrophy in patients with CTPV is clinically significant. When clinical signs are not manifest and routine biochemical tests are not useful for detecting exocrine pancreatic insufficiency, the bentiromide test is highly sensitive and specific for detecting probable pancreatic insufficiency in patients with CTPV.