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Bu çalışma, 12-14 Mayıs 2001 tarihleri arasında Paradise[Bahamalar]’de düzenlenen 8. IMAST 2001 Conference’da bildiri olarak sunulmuştur. Study Design. This is a case report. Objectives. To present a case of neglected major vessel injury after anterior spinal surgery. Summary of Background Data. Vascular complications during spinal surgery are fortunately few in number. The incidence and management of vascular complications during anterior approaches to the thoracolumbar spine are not well known, and it is likely that most acute or delayed vascular injuries and complications are not reported. Methods. A case that underwent anterior spinal surgery for T12 burst fracture with an iatrogenic injury to the aorta was presented. Results. Paraparesis ( Frankel B) was present before last operation and disappeared completely at 30 months of follow-up. Conclusions. As with any complication, the best treatment is prevention. Careful and meticulous exposure of the involved anatomic area is very important for prevention. Early recognition with rapid treatment of vascular complications can reduce potential morbidity and mortality.

Recent clinical studies revealed emotional and cognitive impairments associated with absence epilepsy. Preclinical research with genetic models of absence epilepsy however have primarily focused on dysfunctional emotional processes and paid relatively less attention to cognitive impairment. In order to bridge this gap, we investigated age-dependent changes in learning and memory performance, anxiety-like behavior, and locomotor activity of WAG/Rij rats (a valid model of generalized absence epilepsy) using passive avoidance, Morris water maze, elevated plus maze, and locomotor activity cage. We tested 5 month-old and 13 month-old WAG/Rij rats and compared their performance to age-matched Wistar rats. Results revealed a decline in emotional and spatial memory of WAG/Rij rats compared to age-matched Wistar rats only at 13 months of age. Importantly, there were no significant differences between WAG/Rij and Wistar rats in terms of anxiety-like behavior and locomotor activity at either age. Results pointed at age-dependent learning and memory deficits in the WAG/Rij rat model of absence epilepsy., NA

International audience; Glial cells are responsible for maintaining brain homeostasis. Modification of the viability and functions of glial cells, including astrocytes and microglia, are associated with neuronal death and neurological diseases. Many toxins (heavy metals, pesticides, bacterial or viral toxins) are known to impact on brain cell viability and functions. Although recent publications suggest a potential link between environmental exposure of humans to mycotoxins and neurological diseases, data regarding the effects of fungal toxins on brain cells are scarce. In the present study, we looked at the impact of deoxynivalenol (DON), a fungal ribotoxin, on glial cells from animal and human origin. We found that DON decreased the viability of glial cells with a higher toxicity against microglial cells compared with astrocytes. In addition to cellular toxicity, DON affected key functions of glial cells. Thus, DON caused a biphasic effect on the neuroinflammatory response of microglia to lipopolysaccharide (LPS), while sublethal doses of DON increased the LPS-induced secretion of TNF-α and nitric oxide, toxic doses inhibited it. In addition to affecting microglial functions, sublethal doses of DON also suppressed the uptake of L-glutamate by astrocytes. This inhibition was associated with a modification of the expression of the glutamate transporters at the plasma membrane. Our results suggest that environmental ribotoxins such as DON could, at low doses, cause modifications of brain homeostasis and possibly participate in the etiology of neurological diseases in which alterations of the glia are involved. © 2011 Wiley-Liss, Inc.

It is now well established that the kisspeptin neurons of the hypothalamus play a key role in regulating the activity of gonadotropin-releasing hormone (GnRH) neurons. The population of kisspeptin neurons residing in the rostral periventricular region of the third ventricle (RP3V), encompassing the anteroventral periventricular (AVPV) and periventricular preoptic nuclei (PVpo), are implicated in the generation of the preovulatory GnRH surge mechanism and puberty onset in female rodents. The present study examined whether these kisspeptin neurons may express other neuropeptides in the adult female mouse. Initially, the distribution of galanin, neurotensin, met-enkephalin (mENK), and cholecystokinin (CCK)-immunoreactive cells was determined within the RP3V of colchicine-treated mice. Subsequent experiments, using a new kisspeptin-10 antibody raised in sheep, examined the relationship of these neuropeptides to kisspeptin neurons. No evidence was found for expression of neurotensin or CCK by RP3V kisspeptin neurons, but subpopulations of kisspeptin neurons were observed to express galanin and mENK. Dual-labeled RP3V kisspeptin/galanin cells represented 7% of all kisspeptin and 21% of all galanin neurons whereas dual-labeled kisspeptin/mENK cells represented 28–38% of kisspeptin neurons and 58–68% of the mENK population, depending on location within the AVPV or PVpo. Kisspeptin neurons in the arcuate nucleus were also found to express galanin but not mENK. These observations indicate that, like the kisspeptin population of the arcuate nucleus, kisspeptin neurons in the RP3V also co-express a range of neuropeptides. This pattern of co-expression should greatly increase the dynamic range with which kisspeptin neurons can modulate the activity of their afferent neurons.

International audience; A common set of odorous molecules may indicate female receptiveness across species, as male rats display sexual arousal when exposed to the odour of oestrous faeces from rats, vixens and mares. More than 900 different compounds were identified by GC-MS analyses performed on faeces samples from di-oestrous and oestrous females and from males of the three species. Five carboxylic acids were found in lower concentrations in faeces from all oestrous females. We subjected 12 sexually trained male rats to a 30 min exposure to different dilutions of a mixture of these five molecules in the same proportions as found in female oestrous faeces. The behavioural responses of the rats were compared to those displayed when exposed to water (negative control) and faeces from oestrous female rats (positive control). Frequency of penile erections were found to be significantly dependent on mixture dilution, with two intermediate dilutions eliciting frequencies of penile erections that did not differ from those obtained during exposure to oestrous female rat faeces. Higher and lower dilutions did not elicit more penile erections than observed with water. These results support our hypothesis that a small set of odorous molecules may indicate sexual receptiveness in mammalian females.

Fipronil is a phenylpyrazole insecticide known to elicit neurotoxicity via an interaction with ionotropic receptors, namely GABA and glutamate receptors. Recently, we showed that fipronil and other phenylpyrazole compounds trigger cell death in Caco-2 cells. In this study, we investigated the mode of action and the type of cell death induced by fipronil in SH-SY5Y human neuroblastoma cells. Flow cytometric and western blot analyses demonstrated that fipronil induces cellular events belonging to the apoptosis process, such as mitochondrial potential collapse, cytochrome c release, caspase-3 activation, nuclear condensation and phosphatidylserine externalization. In addition, fipronil induces a rapid ATP depletion with concomitant activation of anaerobic glycolysis. This cellular response is characteristic of mitochondrial injury associated with a defect of the respiration process. Therefore, we also investigated the effect of fipronil on the oxygen consumption in isolated mitochondria. Interestingly, we show for the first time that fipronil is a strong uncoupler of oxidative phosphorylation at relative low concentrations. Thus in this study, we report a new mode of action by which the insecticide fipronil could triggers apoptosis.

This study tested the hypothesis that the ventrolateral column of the midbrain periaqueductal gray (vlPAG) region mediates the hypotension and bradycardia evoked by visceral nociception. To test this, the local anesthetic lidocaine (2%; 0.5 microl) was microinjected into the vlPAG of halothane-anesthetized rats bilaterally and visceral nociception was induced 2 min later by injecting 5% acetic acid (0.5 ml) intraperitoneally. Acetic acid injection caused an abrupt fall in arterial pressure (-12.2+/-2.1 mm Hg) and heart rate (-37+/-93 bpm) lasting approximately 15 min. Lidocaine injection into the vlPAG prevented the fall in arterial pressure and heart rate completely. Cobalt chloride (5 mM; 0.2 or 0.5 microl) injection into the vlPAG also prevented nociceptive hypotension but it did not affect the fall in heart rate significantly. Lidocaine pretreatment also inhibited the depressor response caused by intramuscular formalin (5%; 0.2 ml) administration, a model of deep somatic nociception, although it did not prevent the response completely. To determine if opioid receptors mediate the response, selective mu, delta or kappa opioid receptor antagonists were microinjected into the vlPAG 5 min before intraperitoneal (ip) acetic acid administration. Naltrindole, a delta receptor antagonist, inhibited the response significantly but mu and kappa antagonists were completely ineffective. Lidocaine and naltrindole had no effect when injected into the dorsolateral PAG and did not influence cardiovascular function when injected into the vlPAG of saline treated control animals. These data support the hypothesis that the vlPAG mediates the depressor response evoked by visceral nociception and indicate that delta opioid receptors participate in the response.

Brown tumors are the end stage of primary or secondary hyperparathyroidism. Such lesions are rare because hyperparathyroldism is now usually diagnosed and treated before they develop. Skeletal bone is most frequently involved, whereas sellar-parasellar involvement is extremely rare. We report a patient with a brown tumor involving the sellar-parasellar region associated with primary hyperparathyroidism. The patient's clinical history and biochemical and radiological tests were used for the diagnosis. Excision of the sellar-parasellar mass enabled histopathological confirmation and surgical decompression of neural structures. After the transsphenoidal surgery, excision of a parathyroid adenoma normalized the patient's metabolic status. Brown tumors are rarely associated with complications but occasionally may compress neural structures such as the optic nerve as they enlarge.

OBJECTIVE AND IMPORTANCE: Various intracranial abnormalities, including infectious conditions, may manifest as trigeminal neuralgia. CLINICAL PRESENTATION: A 33-year-old man presented with a 15-day history of right-sided facial pain and numbness. Neurological examination revealed diminished corneal reflex and facial sensation in the right V1–V2 distribution. Magnetic resonance imaging revealed a contrast-enhancing lesion centered at the right pons with extension of the enhancement to the sphenoid sinus. INTERVENTION: Broad-spectrum antibiotics were administered for 6 weeks. This resulted in alleviation of symptoms and resolution of the lesion as revealed by repeat magnetic resonance imaging. CONCLUSION: Presentation of a pons abscess with trigeminal neuralgia is rare, and to the best of our knowledge has not been reported previously. The patient was treated successfully with antibiotics alone.

The aim of this study was to measure the motor conduction time (MCT) and velocity of the lateral pectoral nerve (LPN) in normal subjects and patients with neuropathy. For the LPN, we determined that the average AICT was 3.9 m/s using Erb stimulation with needle recording, and the average motor conduction velocity was 70.6 m/s using Erb stimulation and axilla stimulation with needle recordings in normal subjects. In patients, prolonged MCT in LPN was found in 3 of 6 Patients with unilateral plexopathy and 3 of 4 patients with polyneuropathy. If was determined that MCT and motor conduction velocity in LPN was as sensitive as biceps brachii MCT in patients with unilateral plexopathy. Furthermore, the motor conduction velocity in the LPN may be beneficial to elucidate the localization of involvement in polyneuropathies, such as distal or proximo-distal.

Sarcoidosis is a systemic, idiopathic granulomatous disorder with occasionally surprising clinical presentations. A primary involvement of the optic nerve is particularly important due to visual prognosis. We report here a patient with occult sarcoidosis who presented to us with progressive visual loss as the first and primary manifestation of the disease. The patient underwent surgery for histopathological diagnosis and decompression of the optic nerve. This case demonstrated that sarcoidosis should be considered in the differential diagnosis of any lesion involving the optic nerve.

Although unilateral epidural hematomas are well known, bilateral presentation, especially at the confluens sinuum, is uncommon, and its diagnosis may be delayed, thus causing morbidity. We report a case of acute posttraumatic cortical blindness due to epidural hematoma at the confluens sinuum caused by venous sinus tearing. The epidural hematoma was evacuated and the dural tear was repaired. The patient remained alert throughout the hospitalization. Examination of the visual field revealed recovery postoperatively, and the patient was discharged. We discuss the pathological mechanisms of transient blindness. The importance of anopsia as an early sign of epidural hematoma is emphasized.