Screening of the anticonvulsant activity of some plants from Fabaceae family in experimental seizure models in mice

Fabaceae is the third largest family of flowering plants. Lack of essential oils in the plants of this family can be an advantage in search for safe and effective medicines. In this study the anticonvulsant effect of the leaves of Albizzia julibrissin, Acacia juliflora, Acacia nubica and aerial parts of Astragalus obtusifolius was evaluated in pentylenetetrazole [PTZ] and maximal electroshock [MES] seizure tests. The hydroalcoholic extracts of the plants were obtained by percolation. Different doses of the extracts were injected to the mice intraperitoneally [i.p.] and occurrence of clonic seizures induced by PTZ [60 mg/kg, i.p.] or tonic seizures induced by MES [50 mA, 50Hz, 1sec] were monitored up to 30 min after administration. Acute toxicity of the extracts was also assessed. The safe and effective extract was then fractionated by dichloromethane and anticonvulsant activity of the fractions was determined. Finally, the constituents of the extract and the fractions were screened by thin layer chromatography. Among the extracts, only A. obtusifolius extract showed low toxicity and protective effect against clonic seizures with ED50 value of 3.97 g/kg. Fractionation of the extract led to increase in anticonvulsant activity and ED50 value of 2.86 g/kg was obtained for the aqueous fraction. Phytochemical screening revealed the presence of alkaloids, flavonoids, anthrones and saponins in the aqueous fraction. The presence of anticonvulsant compounds in A. obtusifolius suggests further activity-guided fractionation and analytical studies to find out the potential of this plant as a source of anticonvulsant agent

Saturated picric acid prevents autophagia and self-mutilation in laboratory rats

The dysesthesia and paresthesia that occurs in laboratory rats after spinal cord injury [SCI] results in autophagia. This self-destructive behavior interferes with functional assessments in designed studies and jeopardizes the health of the injured rat. In this study, we evaluated role of saturated picric acid in the prevention of autophagia and self-mutilation. All rats were anesthetized with an intraperitoneal injection of a mixture of ketamine [100 mg/kg] and xylazine [10 mg/kg] for the SCI procedures. In the first 39 rats, no solution applied to the hind limbs, but in the next 26 cases, we smeared the saturated picric acid on the tail, lower extremities, pelvic, and abdomen of the rats immediately after SCI. In the rats without picric acid, 23 rats died following autophagia, but in the 26 rats with picric acid, there was no autophagia [P < 0.001]. Picric acid side effects in skin and gastrointestinal signs such as irritation, redness and diarrhea were not seen in any rat. Saturated picric acid is a topical solution that if used appropriately and carefully, might be safe and effectively prevents autophagia and self-mutilation. When the solution is applied to the lower abdomen and limbs, we presume that its bitterness effectively prevents the rat from licking and biting the limb

[Increased mercury release from dental amalgam restorations after brain magnetic resonance imaging]

The introduction of magnetic resonance [MR] technology as a clinical imaging method has substantially increased the patient exposure to static, gradient and radio frequency of electromagnetic fields. The aim of this study was to assess the release of mercury from human dental amalgam restorations after exposure to electromagnetic fields produced by conventional MR imaging. The pre- and post-interventional study design was used for this investigation. The study participants were composed of individuals who were scheduled for brain MRI and those who had at least 4 teeth with amalgam restorations. These restorations had to be at least one week or older. Thirty individuals, who met the inclusion criteria, were referred to magnetic resonance imaging [MRI] department. A questionnaire was used for each patient to collect basic information on past exposures to electromagnetic fields, occupation and life style. Biological specimens [5cc stimulated saliva] were collected just before and after MRI procedures. The magnetic flux density was 0.23 T, and the patient's duration of exposure to magnetic field was 30 minutes. The collected saliva samples were analyzed by laboratory for mercury level by using cold-vapor atomic absorption technique. The SPSS software and paired t-test were used for statistical analysis of mercury levels. The mean concentrations of mercury in saliva before and after MRI were 0.86 +/- 0.3 mg /dl and 1.13 +/- 0.5 mg /dl respectively. Data analysis using paired t-test showed a statistically significant difference between the mean concentrations of saliva mercury before and after MRI procedures. This study showed significant relationship between increased mercury levels in saliva of patients exposed to magnetic resonance imaging

[Effect of drill-induced hearing loss in the non-operated ear after mastoidectomy by measuring of otoacoustic emission, Amir-Alam and Imam Hospitals [2000]]

Background: The damaging effect of exposure to loud noise on the structures of internal ear has been studied from many years ago. The effect of drill-generated noise on the non-operated ear is one of the problems that are less discussed. This study aims to evaluate the hearing loss that occurs in the non-operated ear in patients who undergo mastoidectomy by use of PTA [pure tone audiometery] and DPOAE [distortion product otoacoustic emission]

Materials and Methods: In this descriptive- analytic study, 49 patients who underwent mastoidectomy in Amir-Alam and Iman Khomeini hospitals, were evaluated for noise trauma generated by drilling on the non-operated ear. Patients were between 9-55 years old [mean age= 29] and they consisted of 25 males and 24 females. The patient's preoperative state were measured by PTA and DPOAE on the opposite ear also the postoperative state were re-evaluated by PTA and DPOAE

Results: As a result, in 4 cases a significant change in PTA thresholds were observed, while two of them showed recovery after one month. Seven cases showed significant change in DPOAE amplitudes, of whom five cases recovered later

Conclusion: In conclusion, the drill-induced hearing loss on the non-operated ear occurs in a few patients and it is often reversible

[Effect of pentoxifylline on the healing of guinea pig perforated tympanic membrane]

Background: Tympanic membrane perforation as a sign of different otologic disorders have multiple causes, for example trauma .Traumatic perforations heal spontaneously in most cases but in large and stable perforation otolarngologist intervention is necessary. In the stable perforation of tympanic membrane, if there isn't infection in the tympanic cavity, the paper patch or myringoplasty may be used. These procedures need remedy charge and time and may be with morbidity and other complications. Recently materials like hyaluronic acid and epidermal growth factors has been used to speed healing of tympanic membrane perforation, and their effect has been proved. Pentoxifylline an anti-thrombotic drug has positive effect on increasing perfusion and wound healing in pathological conditions. Alike we have used pentoxifylline to show it's effect on the healing of guinea pig perforated tympanic membrane

Materials and Methods: This study has been done prospectively, on 32 guinea pig ears

Results and Conclusion: Final otomicroscopic study after three weeks showing no significant difference in the healing rate of tympanic membrane in pentoxifylline group versus control group