Cyclooxygenase‐2 expression and connection with tumor recurrence and histopathologic parameters in gastrointestinal stromal tumors

Tissue cyclooxygenase‐2 (COX‐2) is a rate‐limiting enzyme in prostaglandin synthesis and has been shown to have roles in carcinogenesis and tumor progression. Evaluation of COX‐2 overexpression in malignancies has been performed mostly on tumors of epithelial origin, and little is known about its presence in mesenchymal tumors, especially gastrointestinal stromal tumors (GIST). COX‐2 has been reported to be widely expressed in GIST and has been suggested as a potential diagnostic marker. We evaluated the overexpression and roles of COX‐2 in tumorigenesis in GIST with regard to its relation to prognostic parameters and tumor recurrence. We studied the presence of COX‐2 expression immunohistochemically and its relation to clinicopathologic prognostic variables in 41 cases of GIST. COX‐2 was overexpressed in 21 (51%) of 41 tumors. The extent of overexpression was greater in tumors that recurred after surgical resection. COX‐2 overexpression was also higher in tumors with coagulative necrosis, high mitotic index and an infiltrative pattern of growth. The observation of greater COX‐2 expression levels in GIST with unfavorable histopathologic variables is contrary to previous reports and consistent with the reported roles of COX‐2 in carcinogenesis of epithelial malignancies.     

Auditory brainstem responses in children with congenital heart disease

BACKGROUND: Cyanotic congenital heart diseases usually lead to growth and developmental delay in children due to chronic hypoxemia and undernourishment that may affect the central nervous system. The auditory brainstem responses are determined to assess the maturation and function of the brainstem. Therefore, we used the auditory brainstem responses to investigate the effect of cyanotic congenital heart diseases on brainstem maturation. METHODS: The auditory brainstem responses were investigated in 45 children (23 cyanotic, 22 acyanotic) with congenital heart diseases and compared with the results of 30 healthy counterparts (all children were aged between 2 months and 15 years). RESULTS: The results of auditory brainstem responses were similar in acyanotic patients and in normal children. The cyanotic patients under 1 year of age had more prolonged I-V interpeak latencies than those of control and acyanotic patients (P < 0.05). There was no difference between all groups older than 1 year of age. In cyanotic children, I-V interpeak latencies showed significant negative correlation with arterial oxygen saturation and partial oxygen pressure (P < 0.05). CONCLUSIONS: Cyanotic congenital heart diseases may cause significant retardation on brainstem maturation due to chronic hypoxemia, especially in infants under 1 year of age, whereas acyanotic congenital heart diseases have no effect on auditory brainstem responses.     

Adenosine Sensitive Left Ventricular Tachycardia

Presented here is a 39-year-old male patient with no structural heart disease but a ventricular tachycardia with right bundle branch block morphology and right axis deviation, which is responsive to adenosine. The ventricular tachycardia was initiated by ventricular pacing, shown to originate from the mid-anterior free wall region of the left ventricle and terminated by adenosine. Radiofrequency current application at a site where presumed P potentials were recorded eliminated the tachycardia, a finding that suggests that the origin of the tachycardia may be closely related to the anterior fascicle.     

Effect of hypothyroidism on the nitrergic relaxant responses of corpus cavernosal smooth muscle in rabbits

BACKGROUND: The incidence of hormonal dysfunction as a cause of impotence remains controversial. However, several recent studies have reported evidence of hormonal abnormalities in 25-35% of impotent men. Hypothyroidism has been reported to occur in 6% of impotent men. METHODS: In the present study, we examined nitrergic responses in hypothyroidism in rabbit corpus cavernosum and compared them with controls. RESULTS: Carbachol-induced relaxation responses and electrical field stimulation (EFS)-induced frequency-dependent relaxations decreased significantly in hypothyroid rabbits. Papaverine and sodium nitroprusside (SNP)-induced relaxation responses did not change significantly in hypothyroid rabbits. The contraction responses of phenylephrine and EFS-induced frequency-dependent contractions were significantly decreased in the hypothyroid group. CONCLUSIONS: We can speculate that the reduction of relaxant responses to EFS and carbachol in hypothyroid rabbits can depend on a decreased release of nitric oxide (NO) from nitrergic nerves and endothelium or a reduction of muscarinic receptor density. Also, decreases in contraction responses may depend on diminished adrenoceptor density.     

Therapeutic effect of spiramycin in brucellosis

OBJECTIVE: This study was undertaken to investigate the usefulness of spiramycin in treatment for brucellosis in an animal model. METHODS: Eighty-four Sprague-Dawley rats were infected by intraperitoneal injection of Brucella melitensis suspension. Seven days after inoculation, four rats were selected randomly, killed and spleen cultures and Brucella standard tube agglutination test were carried out. All four rats were found to be infected. Eighty adult rats were randomly divided into four groups of 20 rats each. Tap water was given to the first group. Rifampicin 50 mg/kg per day and doxycycline 40 mg/kg per day were given to the second group, spiramycin 50 mg/kg per day orally was given to the third group, and a combination of spiramycin and rifampicin at the same dose and period was given to the fourth group. Duration of therapy regimens in all groups was 21 days. The spleens of all 80 rats were removed aseptically, homogenized, and placed onto Brucella agar plates to determine if viable bacteria were present. RESULTS: Bacterial growth occurred in all of the rats' spleens in the first group and in two rats' spleens in the spiramycin group. Mean colony forming unit (c.f.u.) values were at the highest in the first group. The effectivities of spiramycin and rifampicin-spiramycin were similar to rifampicin-doxycycline. There were no differences in the treatment results between the three groups that received combined rifampicin-doxycycline, rifampicin-spiramycin and only spiramycin (P>0.05). CONCLUSIONS: The results show that spiramycin cures experimental rat brucellosis and may be an effective alternative in the therapy of human brucellosis.     

PREDICTORS OF SUICIDAL BEHAVIOR IN A SAMPLE OF TURKISH SUICIDE ATTEMPTERS

In a Turkish sample, 100 suicide attempters, were compared with 60 healthy controls on measures of hopelessness, depression, and suicidal ideation. Suicide attempters were more depressive, more hopeless, and displayed greater suicidal ideation than healthy controls. Depression severity rather than hopelessness correlated with suicidal intent. Suicide lethality was independent of depression severity, hopelessness, and suicidal ideation and intent, suggesting that lethality is likely due to chance.