Ultrastructural changes in the circumventricular organs after experimental subarachnoid hemorrhage

Objectives: Circumventricular organs (CVOs) are fine, periventricular, neurotransmitter-rich structures that are devoid of a Blood-brain barrier and are known for their secretory role controlling fluid and electrolyte balance, thirst and even reproduction. Common pathologies of the brain such as trauma or bleeding affect CVOs, and hence their function. However, at what stage of these disease processes are CVOs affected and the time sequence of their recovery is still not clear. The aim of this study was to detect the morphological changes in CVOs using electron microscopy after experimental subarachnoid hemorrhage (SAH). Methods: Experimental SAH was induced by transclival puncture of the basilar artery. Both scanning and transmission electron microscopic examination of the representive sections from each CVO was undertaken. Results: Electron microscopy has shown that after SAH, the cells that form the CVOs exhibit signs of cellular necrosis with margination of the nucleus as well as cytoplasmic, mitochondrial and axonal edema. The subfornicial organ and organum vasculosum lamina terminalis appear to be more vulnerable to the effects of SAH than the median eminence or area postrema. Discussion: Considering the fact that the experimental SAH model we have used is very similar to the momentary rupture of an aneurysm with secondary reflex spasm to seal the hole, it will not be unrealistic to consider that similar effects may also take place in the clinical setting. © 2005 W. S. Maney & Son Ltd

Kemiksel çekiç parmak tedavisi için ekstansiyon blok pinleme: Transfiksasyon pini gerekli mi? [Extension-block pinning to treat bony mallet finger: Is a transfixation pin necessary?]

PubMed ID: 31135948BACKGROUND: Extension-block pinning is a popular treatment for mallet fractures, but it is associated with several pitfalls. Of note, transfixation Kirschner wires used to fix the distal interphalangeal (DIP) joint may cause iatrogenic nail bed injury, bone fragment rotation, chondral damage, or osteoarthritis. The objective of this study was to determine whether a transfixation pin was necessary for extension-block pinning in the treatment of bony mallet fracture. METHODS: Patients were treated with a pin-orthosis extension-block technique if they had been diagnosed with a type IVB mallet fracture according to Doyle's classification. Radiological outcomes were evaluated based on postoperative X-ray results, and functional outcomes were evaluated using Crawford's criteria. RESULTS: Thirteen patients (9 males and 4 females) with a mean age of 26 years were included. The mean time between the injury and surgery was 3.3 days, and the mean follow-up period was 8.2 months (range: 4-12 months). Radiographic bone union was achieved in all patients within an average of 5.1 weeks (range: 5-6 weeks). At the final follow-up, the DIP joint had an average degree of flexion of 76.1° (range: 65°-80°) and an average extension deficit of 3.84° (range: 0°-15°). According to Crawford's criteria, 8 patients had excellent results, 4 patients had good results, and 1 patient had a fair result. No patient reported pain at the final follow-up. CONCLUSION: Satisfactory clinical and radiological outcomes were obtained with the pin-orthosis extension-block technique. Future prospective and randomized studies are justified to confirm the efficacy of this technique

Anatomic Study Of Complex Anomalies Of The Digastric Muscle And Review Of The Literature

Scopu

Effects of repeated sevoflurane anesthesia on renal function: An animal study

Purpose: The effect of repeated administrations of sevoflurane in rats was evaluated with free inorganic plasma fluoride concentrations and the effect of sevoflurane on the kidneys. Methods: Thirty-five rats were divided into two groups. The control group consisted of 7 rats, and the sevoflurane group consisted of 28 rats. The sevoflurane group was divided equally into 4 subgroups according to the time of sacrifice (S1, S3, S5, S10). All rats in the sevoflurane group were administered 3% sevoflurane for 30 minutes for 5 days. After anesthesia, the rats were sacrificed at the end of the 1st, 3rd and 5th days. The other 7 were kept without anesthesia for 5 days and they were sacrificed at the end of the 10th day. Plasma inorganic fluoride concentrations were measured by ion-selective electrode methods in aspirated heart blood samples. Renal biopsies were taken just after sacrifice and the renal histopathologic effects of sevoflurane were investigated under light and transmission electron microscopy (TEM). Results: Plasma fluoride concentrations were significantly different between the sevoflurane and control groups. However, there was no statistical difference between the sevoflurane subgroups. Plasma BUN levels did not differ between the control and sevoflurane groups, except on the 10th day. Ultrastructurally, the sevoflurane subgroups (S-3, S-5, S-10) showed significant tubular histopathologic changes compared to the control group. However, these changes showed a significant regression on the 10th day. Conclusion: Repeated sevoflurane administration is a safe procedure since histopathological changes showed significant regression