The Effect of Tizanidine on Chronic Vasospasm in Rats

Summary ? Background. Cerebral vasospasm after subarachnoid hemorrhage (SAH) has remained a major cause of morbidity and mortality in patients with SAH. Excitatory neurotransmitters are gathered in the extracellular space during ischemia due to cerebral vasospasm and initiate or stimulate a series of pathophysiological biochemical processes which consequently lead to neuronal death. Tizanidine (Sandoz compound DS 103–282, 5-chloro-4,2 (2-imidazolin-2-yl-amino)-2,1,3-benzothiazol hydrochloride) is a centrally-acting muscle relaxant and a selective α 2 adrenoreceptor agonist which shows its effect by stimulating presynaptic α 2 adrenoreceptors in central ASPergic and GLUergic system by inhibiting aspartic acid and glutamic acid release. In this study, the effect of Tizanidine on vasospasm was evaluated.  Methods. We used a femoral artery vasospasm model in rats which has been described by Okada et al. 60 rats were examined in three groups. The first group was used as control group (Control) (n=20), in the second group subarachnoid hemorrhage was performed (SAH) (n=20), in the third group Tizanidine was administered in addition to SAH (SAH+Tizanidine administration) (n=20). Animals in SAH+Tizanidine administration group received 0,3 mg/kg/day intraperitoneally for 7 days. Seven days after the experiment, after perfusion-fixation, 10 mm segments of both femoral arteries were removed and the femoral artery was prepared for light microscope examination, scanning and transmission electron microscopy and for morphometric analysis.  Results. There was a statistically significant difference between the electron, scanning and light microscopic observations and morphometric analysis of SAH+Tizanidine administration group and SAH group, and no statistically significant difference between SAH+Tizanidine administration group and control group.  Conclusion. This study has disclosed that Tizanidine administration before the vasospasm reduces ultrastructural and morphometric vasospastic insult significantly. However, the clinical application of Tizanidine as a protective and therapeutic agent in cerebral vasospasm needs further studies including the employment of clinically more relevant SAH models.     

Mesoatrial shunt in Budd-Chiari syndrome

BACKGROUND: The operations with proven effects on survival in Budd-Chiari syndrome are shunt operations and liver transplantation. PATIENTS AND METHODS: Between 1993 and 1999 (June), 13 cases of Budd-Chiari syndrome have been treated surgically. Four cases had concomitant thrombosis of the inferior vena cava; the others had marked narrowing of the lumen due to the enlarged caudate lobe. Mesoatrial (n = 12) or mesosuperior vena caval (n = 1) shunts were constructed with ringed polytetrafluoroethylene grafts. RESULTS: The median portal pressure fell from 45 (range 32 to 55) to 20 (range 11 to 27) cm H(2)O (P <0.001). Two patients died in the early postoperative period. One patient who did not comply with anticoagulant treatment had a shunt thrombosis in the second postoperative year. The other 10 patients are alive without problems during a median 42 (range 1 to 76) months of follow-up. CONCLUSION: Mesoatrial shunt with a ringed polytetrafluoroethylene graft is effective in Budd-Chiari syndrome cases with thrombosis or significant stenosis in the inferior vena cava.     

Effect of nitric oxide synthase inhibitor on experimentally induced burn wounds

BACKGROUND: Nitric oxide (NO) may have an important role in the healing of burn wounds. This study investigated the effect of NO on experimentally induced burn wounds by preventing NO synthesis. METHODS: A total of 40 mice weighing 25 to 30 g were used in this study. The shaved skin on the back of the mice was immersed in 100 degrees C water for 10 seconds to achieve a partial-thickness scald burn. The mice were divided into two groups of 20. In group I (control group), 17.5 mg/kg of serum physiologic (placebo) was injected intraperitoneally two times a day for 15 days. In group II (study group), 17.5 mg/kg of aminoguanidine (NO synthase inhibitor) was injected intraperitoneally two times a day for 15 days. On day 15 of the burn, the animals were killed and the burn areas were investigated histologically. Histologic changes such as epithelial proliferation, abscess, collagen, and granulation tissue were evaluated. RESULTS: Epithelial proliferation, formation of collagen, and granulation tissue with rich capillaries observed in the control group were statically significantly higher than those observed in the study group (z = -2.022, p < 0.05; z = -2.02, p < 0.05; and z = -2.022, p < 0.05; respectively). CONCLUSION: We concluded that healing of the burn wound is delayed by preventing NO synthesis.     

Embolization of the deep dorsal vein for the treatment of erectile impotence due to veno-occlusive dysfunction

PURPOSE: We evaluate the effectiveness of deep dorsal vein embolization for the treatment of venous impotence. MATERIALS AND METHODS: A total of 32 impotent patients with veno-occlusive dysfunction underwent deep dorsal vein embolization. The condition was suspected based on findings of penile Doppler ultrasonography and cavernosometry. The diagnosis was confirmed with pharmacocavernosography that appeared to delineate venous leakage. During the procedure we isolated and cannulated the deep dorsal vein through a small dorsal penile incision with the patient under local anesthesia. We used a mixture of the tissue glue, N-butyl cyanoacrylate, and lipodol for embolization, with a total volume of 5 ml. injected antegrade into the previously catheterized dorsal vein under fluoroscopic control. As soon as we observed the occluded veins we performed repeat pharmacocavernosography. At 3-month followup patients were reassessed with history and cavernosometry. Followup ranged from 12 to 36 months (median 25). RESULTS: Of 32 patients 22 (68.7%) regained sexual activity, which was confirmed by cavernosometry. The remaining 10 patients (31.3%) experienced little if any clinical response, which correlated with cavernosometry. There were no significant side effects. CONCLUSIONS: Deep dorsal vein embolization for venogenic impotence is simple, effective and safe, and appears to be cost-effective. The results obtained in this limited number of patients are promising and justify trials in larger groups.     

Sacrococcygeal extraspinal ependymomas: the role of coccygectomy

BACKGROUND: Ependymomas, the common glial tumors of the spinal cord, occur occasionally outside the central nervous system and are called exstraspinal ependymomas (EEP). EEPs are found primarily in sacrococcygeal region during childhood. The pathogenesis and the treatment of the sacrococcygeal (SC) ependymomas are still controversial. Therefore, we present our case with metaanalysis of other case reports to determine the optimal treatment modality for SC EEPs. METHODS: A metaanalysis of case reports of SC EEPs, including the current case, was conducted. Also all available case reports of EEPs, without age limit, were analyzed to determine the distribution of EEPs localization. RESULTS: EEPs usually are found in teratoma localizations such as the SC area, ovary, paraovarian structures, and medastinum. The distribution of EEPs localization differs with age. Local recurrence rate of EEPs after coccyx excision is zero, however, it increases to 71% when the coccyx was left behind. CONCLUSION: The identical clinical characteristics of the SC teratomas and EEPs imply that the SC EEPs may be monophasic teratomas as their ovarian counterparts are named. Coccyx excision is an important part of the surgical treatment of these tumors, with an apparent decrease in the recurrence rate.