Hakan Aytan

Determination of Oestrous Cycle of the Rats by Direct Examination: How Reliable?

For determination of the oestrous cycle in rats classical Papanicolaou technique has long been used successfully. Instead of using many stains in Papanicolaou, staining the vaginal secretions with only methylene blue has also been defined. Recently a new technique in which vaginal samples are directly examined under light microscope has been introduced. The aim of this study was to assess the reliability of this new technique by comparing it with the classical staining techniques. From 20 Wistar rats 60 vaginal samples were collected with a micropipette, three from each. Briefly, the vagina was flushed two to three times then the fluid was placed onto a glass slide. The fluid was equally distributed onto three glass slides. The glass slides were coded. Two samples were stained with Papanicoloau and methylene blue while the other one was examined directly. Determination of the phases of the oestrous cycle was made by the same histologist who was blinded to the groups and coding system. After determination of the oestrous phase in all samples, the results were compared and it was found that the results were matching. In conclusion, the same results can be obtained with the direct examination technique and this technique is reliable, so there is no need to use relatively time‐consuming, less practical and more expensive techniques such as Papanicolaou or methylene blue.

Effect of Peroxisome Proliferator—Activated Receptor-γ Agonist Rosiglitazone on the Induction of Endometriosis in an Experimental Rat Model

Objective: To assess the effect of the peroxisome proliferator-activated receptor (PPAR)-γ agonist rosigliotazone on the induction of endometriosis in a rat model. Methods: Endometriosis was surgically induced in 28 rats by transplanting an autologous fragment of endometrial tissue onto the inner surface of the abdominal wall. Group I was assigned as control and no medication was administered. Starting 3 days before the operation and continuing for 4 weeks, 0.2 mg/kg/d rosiglitazone was administered to the study group orally. Four weeks later rats were killed and ectopic uterine tissues were evaluated morphologically and histologically. Scoring systems were used to evaluate preservation of epithelia. Results: Four rats in the study group and one rat in the control group died of complications related to surgery. There was a significant difference in post-treatment spherical volumes (64.00 mm3 [interquartile range (IQR): 354.42] vs 41.60 mm3 [IQR: 37.87], P = .018) and explant weights (77.97 mg [IQR: 431.27] vs 47.24 mg [IQR: 43.01], P = .005) between control and rosiglitazone-treated groups. The epithelia were found to be preserved significantly better in the control group when compared with the roziglitazone-treated group (2.00 [IQR:2.00] vs 0.00 [IQR:2.25], P = .014). Conclusions: Rosiglitazone was found to affect the induction of endometriosis negatively in this experimental rat model and seemed to interfere with the growth and maintenance of the uterine explant.

Leflunomide—an Immunomodulator—Induces Regression of Endometrial Explants in a Rat Model of Endometriosis:

Objective: To test if leflunomide, an immunomodulator, could impede the growth of an ectopic aterine tissue. Methods: Endometriosos was surgically induced in 26 rats by transplanting an autologous fragment of endometrial tissue onto the inner surface of the abdominal wall. Four weeks later two rats were killed. The volume and weight of the implants were measured. The remaining rats were randomly grouped, and in group 1 no medication was given. To the rats in group 2, 35 mg/kg/d of leflunomide was administered orally. Four weeks later, rats were killed and ectopic uterine tissues were reevaluated morphologically and histologically. A scoring system was used to evaluate preservation of epithelia. Results: Two rats in the control group died 5 weeks after surgery. There was a significant difference in post-treatment spherical volumes (139.1 ± 92.8 versus 33.5 ± 12.5 mm30 and explant weights (156.3 ± 105.6 versus 38.6 ± 12.6 mg) betwee the control and leflumomide-treated groups. The epithelia were found to be preserved significantly better in the control group when compared with the leflunomide-treated group (medium 2.5 [interquartile range, 1.25] versus median 1.00 [interquartile range, 1.5]). Conclusion: Leflunomide appeared to cause regression of experimental endometriosis in rats.

Peroxisome proliferator‐activated receptor‐gamma agonist rosiglitazone reduces the size of experimental endometriosis in the rat model

Background:  The effect of rosiglitazone, an activator of peroxisome proliferator‐activated receptor‐gamma, on the growth of ectopic uterine tissue was assessed.

Comparison of the use of electrothermal bipolar vessel sealer with harmonic scalpel in total laparoscopic hysterectomy

Aim:  The aim of the present study was to compare the use of electrothermal bipolar vessel sealer (EBVS) with harmonic scalpel (HS) during total laparoscopic hysterectomy with respect to operation time, estimated blood loss and related complications.

A novel antibiotic, linezolid, reduces intraperitoneal adhesion formation in the rat uterine horn model

Objective. To examine the effects of linezolid in prevention of adhesion formation in a rat uterine horn model. Design. Prospective randomized study. Setting. University Experimental Animal Research Laboratory Center. Sample. Ninety female Wistar albino rats. Methods. A dose response study was first conducted with 60 Wistar albino rats that were randomly assigned to six equal groups by administering vehicle (control), 5 mg/kg (Group 1), 15 mg/kg (Group 2), 50 mg/kg (Group 3), 100 mg/kg (Group 4), and 150 mg/kg (Group 5) linezolid starting three days before the adhesion inducing operation and continuing for 14 days postoperatively. Adhesion was scored clinically with a scoring system. The minimum effective dose was found to be 100 mg/kg/day. With this dose time response (starting three days before the operation and continuing for seven days), only preoperative and postoperative administration studies were conducted. Main outcome measures. Extent and severity of adhesions. Results. Total adhesion scores in the control and Groups 1 and 2 were significantly higher when compared with Groups 4 and 5, but not with Group 3. There were no significant differences in the adhesion scores between Groups 3, 4, and 5. In time response arm a total of 10 days treatment was not as effective as 17 days treatment. In postoperative and preoperative arms of the study, it was found that administration of linezolid only postoperatively or preoperatively did not affect adhesion formation significantly when compared with the control group. Conclusion. Linezolid was found to reduce intraperitoneal adhesion formation.

Comparison of the adhesion scoring systems used in animal models and assessment of interobserver reproducibility

Two commonly used adhesion scoring systems were compared and the interobserver variability was assessed in 30 Wistar albino rats. Thirty‐five milligrams per kilogram leflunomide was administered orally and intraperitoneally. Two weeks later, adhesion formation was assessed using the two scoring systems. The results showed that the two currently used adhesion scoring systems are subjective and the final results change depending on the observer and the type of the scoring system that has been used.

Office hysteroscopic evaluation of endometrium: can we hit the target?

ObjectivesThe objective was to determine the value of office hysteroscopy in the diagnosis of endometrial hyperplasia by comparing the patients who had hysteroscopic diagnosis of hyperplasia with the results of histopathologic examinations, and to try to describe the visual criteria.Material and methodsTwo hundred and sixteen premenopausal and 114 postmenopausal patients who were admitted to the endoscopic surgery department between January 2000 and March 2001 were enrolled. Visual diagnoses of endometrial hyperplasia with office hysteroscopy were compared with the histopathological results of the endometrial specimen.ResultsPathology confirmed 50 of the 70 hysteroscopically-diagnosed hyperplasia patients. The positive predictive value of office hysteroscopy was 71.4% and the negative predictive value was 95.4% in the diagnosis of endometrial hyperplasia.ConclusionThe accuracy of hysteroscopic evaluation of the uterine cavity is extremely encouraging. Office hysteroscopy, which has a high diagnostic reliability and minimal discomfort, appears to be an ideal method of diagnosis and follow-up of patients with endometrial hyperplasia.

Cervical Partial Hydatidiform Molar Pregnancy

Background: Cervical hydatidiform molar pregnancy is an exceedingly rare occurrence that has been reported only twice before. Case: We report a 25-year-old, G4P1D&C2 woman with a positive pregnancy test and vaginal bleeding. A cervical pregnancy with hydatidiform mole was detected on transvaginal ultrasound and color Doppler examinations. Magnetic resonance imaging was used to localize the lesion. Dilatation and curettage was performed and bleeding that was initially brisk ceased after bimanual pressure. Histopathological examination revealed a partial hydatidiform molar pregnancy. Serial β-hCG measurements showed a decline without need for adjuvant chemotherapy. Conclusion: Conservative fertility-sparing management was successful in this potentially fatal rare case.

Does hysterectomy affect ovarian function? Histopathologic evaluation and serum FSH, inhibin A, and inhibin B levels in an experimental rat model.

OBJECTIVE To evaluate the effects of hysterectomy with ovarian conservation on ovarian histology, and FSH, inhibin A, and inhibin B plasma levels. STUDY DESIGN Forty-five female Wistar albino rats were used in this study and randomly divided into two groups: hysterectomy (n=30) and sham-operated (n=15). Blood samples were collected before and after (50 and 100 days) abdominal hysterectomy from both groups to measure plasma levels of FSH, inhibin A, and inhibin B. All animals were sacrificed by decapitation to obtain ovaries for histological examination. For statistical analyses, Mann-Whitney U, Chi-square, Wilcoxon matched pairs signed rank sum tests, and two-sided variance analysis were used and statistical significance was defined as p<0.05. RESULTS There was no difference in hormonal variables between groups when the time interval was considered completely [p>0.05 (for FSH p=0.962; for inhibin A p=0.321; for inhibin B p=0.476)]. In the hysterectomy group, the inhibin B level at postoperative day 50 was significantly lower than the control group (p=0.007) and at postoperative day 100, inhibin A concentrations were increased significantly when compared with the levels at both baseline and postoperative day 50 (p<0.001). Histopathologic evaluation of ovaries 100 days after hysterectomy showed that ovaries from the hysterectomy group had significantly fewer primary (p=0.01), preantral (p<0.001), and antral follicles (p<0.001), and significantly more corpora lutea (p<0.001), atretic (p=0.02), and cystic follicles (p=0.003). CONCLUSION The results of this experimental rat model suggest that hysterectomy may affect ovarian function.