In the hippocampus in vivo,nitric oxide does not appear to function as an endogenous antiepileptic agent

Using a reverberatory epilepiform discharge of hippocampal-parahippocampal circuits termed maximal dentate activation, this study investigated whether the local release of nitric oxide within these circuits functions as an antiepileptic agent. Two nitric oxide synthase inhibitors (l-nitro-arginine methyl ester and 7-nitro-indazole) and a guanylate cyclase inhibitor (methylene blue) were tested, and none had a significant effect on the time to onset or duration of maximal dentate activation. A membrane-permeable analogue of cyclic guanosine monophosphate (cGMP), 8-bromo-cGMP, caused an increase in the time to onset and a decrease in the duration of maximal dentate activation. The number of neurons expressing NADPH diaphorase activity (a marker for nitric oxide synthase) was also examined after repeated elicitation of maximal dentate activation. After 18 seizures there was a significant, but transient, decrease in the number of hilar/subgranular neurons that were NADPH diaphorase-positive. The decrease was only seen at 1 h after the last seizure. There was no induction of NADPH diaphorase activity. These results are not consistent with the hypothesis that, in hippocampal-parahippocampal circuits in vivo, nitric oxide is released in response to neuronal activity and then acts to terminate the neuronal activity.     

The significance of coasting duration during ovarian stimulation for conception in assisted fertilization cycles

BACKGROUND: Withholding gonadotrophin administration and postponing HCG injection, termed coasting, has been suggested as a treatment modality in cases of impending ovarian hyperstimulation syndrome (OHSS). It presents an opportunity to reduce the risk of OHSS and salvage the treatment, without apparent compromise to outcome. However, the duration of the coasting period, which would maintain the advantage without reducing conception rate, has not been fully established. In this retrospective study, we attempted to define the optimal interval of coasting in patients at risk of developing OHSS. METHODS: Patients were grouped according to the number of days elapsed between cessation of gonadotrophins and administration of HCG. Overall, out of 207 patients (mean age 30.76 +/- 0.33 years) coasting lasted 1 day in 39 cycles (18.8%), 2 days in 61 cycles (29.4%), 3 days in 49 cycles (23.6%) and > or = 4 days in the remaining 58 cycles (28.5%). RESULTS: There was no difference between the groups in patients' age, serum estradiol concentrations at the time of HCG administration, oocyte maturity, fertilization and embryo cleavage rates. However, patients in whom coasting lasted > or = 4 days had significantly reduced implantation (10.5%) and pregnancy (26.7%) rates compared with patients with a shorter coasting interval (ranges 18.4-27.9 and 41-55.7% respectively; P < 0.05). CONCLUSION: Coasting for >3 days appears to reduce implantation and pregnancy rates while in-vitro oocyte and embryo quality do not appear to be affected. We suggest that in patients who need coasting for >3 days, cryopreservation of embryos should be considered.     

Comparison of agonistic flare-up-protocol and antagonistic multiple dose protocol in ovarian stimulation of poor responders: results of a prospective randomized trial

The management of poor responders in IVF has always been a big problem. The ideal approach has yet to be formulated. In this study we aim to compare two alternative stimulation protocols. A total of 48 poor responder patients described from previous cycles were included and grouped into two: group I consisted of 24 patients in 24 cycles in which leuprolide acetate (40 microg s.c. per day) was initiated on cycle day 2 followed by exogenous gonadotrophins on cycle day 3; group II consisted of 24 patients in 24 cycles in which ovarian stimulation included gonadotrophin-releasing hormone (GnRH) antagonist (cetrorelix, 0.25 mg daily during late follicular phase) administration. While only the oestradiol concentrations on the day of HCG were lower in group II compared with group I, the clinical pregnancy and implantation rates among groups did not show any significance. The impact of these two regimens in ovarian stimulation of poor responders seem to be same and to establish these results further randomized studies with larger sample sizes are required.     

Dextromethorphan attenuates ethanol withdrawal syndrome in rats

The effects of dextromethorphan (DM), a noncompetitive antagonist of the N-methyl-D-aspartate (NMDA) receptors, have been investigated on ethanol withdrawal signs in rats. Ethanol (7.2% v/v) was given to rats in a liquid diet for 16 days. DM (10, 20, and 40 mg/kg) and saline were injected intraperitoneally at the third hour of ethanol withdrawal. DM (40 mg/kg) and ethanol dependent saline were also administered to ethanol naive rats. DM (40 mg/kg) did not produce any significant change in locomotor activity in ethanol naive rats. The effects of DM on locomotor activity and total ethanol withdrawal score were evaluated at the fourth and sixth hours of ethanol withdrawal. DM inhibited locomotor hyperactivity at these periods. DM also reduced total ethanol withdrawal score from the fourth hour to the sixth hour, and it significantly decreased audiogenic seizures. Seizure susceptibility after chronic ethanol exposure may be dependent upon sensitization or upregulation of NMDA processes and NMDA receptors. Our results suggest that inhibition of NMDA receptors by DM alleviates signs of ethanol withdrawal.     

Perianal infections: Reader agreement and diagnostic performance of fat‐suppressed contrast‐enhanced MRI

We aimed to determine the diagnostic performance of the contrast‐enhanced fat‐suppression technique in the detectability of perianal infections and to compare this technique with different MR sequences used for this purpose. Thirty consecutive patients with clinically suspected anorectal infections were examined with fast spin‐echo (FSE) T2‐weighted, short‐inversion‐time inversion recovery (STIR), and fat‐suppressed and non‐fat‐suppressed T1‐weighted spoiled gradient‐echo (SGE) (in‐phase) dynamic contrast‐enhanced sequences. The results of MRI were correlated with the findings of surgery, which was considered as the standard of reference. Receiver‐operating‐characteristic curves were reconstructed to describe and compare the diagnostic value of each MR technique. The values of kappa were used as a measure of observer reliability. Diagnostic performances of STIR, FSE T2‐weighted and fat‐suppressed and non‐fat‐suppressed, contrast‐enhanced SGE T1‐weighted techniques showed statistically insignificant differences in detection of perianal infections. There was almost perfect interobserver agreement regarding the presence of lesions on each MR technique. Fat‐suppressed, contrast‐enhanced SGE T1‐weighted MRI showed adequate diagnostic performance in the detection of perianal infections. However, its significance is not different from the other MR sequences used for the present study.     

Pregnancy-associated myocardial infarction

Acute myocardial infarction (AMI) is a rare, but possibly catastrophic event during pregnancy, delivery, or puerperium, leading to a high mortality rate. It has different pathogenic mechanisms, such as atherosclerosis, vasospasm, thrombosis, and coronary dissection. Although MI has been reported in pregnant women at all stages of pregnancy and postpartum, it occurs more commonly in the third trimester. Pregnancy-associated MI most commonly involves the anterior wall. Pregnancy itself is an independent risk factor for MI, conferring a fourfold higher risk than that of nonpregnant women matched for age. We report the case of a 27-year-old primigravida at 30 weeks’ gestation presenting with anterior MI, secondary to severe stenosis of the left anterior descending coronary artery, treated with emergency percutaneous coronary intervention.