Carotid artery occlusion for the treatment of symptomatic giant carotid aneurysms: a proposal of classification and surgical protocol

Giant intracranial aneurysms are rare disorders that represent only 5 % of all intracranial aneurysms; they have a wide variety of presentations including rupture, embolic effects, and mass effect symptoms that can mislead the diagnosis to tumors rather than aneurysms. Their treatment is difficult and carries higher morbidity and mortality than usual aneurysms due to their complex nature. This study involved retrospective analysis of data of 28 patients, managed between 2006 and 2012, suffering from giant internal carotid artery (ICA) aneurysms with various presenting symptoms, none of which was hemorrhage. They were all evaluated by BOT prior to any intervention; they were subjected to various treatment strategies including selective coiling, parent artery occlusion with or without bypass, aneurysm trapping with or without bypass, and patients were followed for a period ranging from 6 months to 5 years. Out of 26 patients with giant aneurysms with mass effects, 16 patients showed full recovery (61.5 %), 5 showed partial improvement (19.2 %), and 5 showed no change in mass effect symptoms (19.2 %). One patient died (3.5 %). Symptoms such as TIA or epistaxis showed complete recovery. This study shows that a well-designed protocol aiming at parent artery sacrifice will yield good to excellent results in managing ICA giant aneurysms, and it also shows that parent artery sacrifice is superior to other forms of treatment of these lesions regarding recurrence rates, morbidity, and mortality.     

Enhancing mandibular bone regeneration and perfusion via axial vascularization of scaffolds

Objective

Reconstruction of large and complex bone segments is a challenging problem facing maxillofacial surgery. The majority of current regenerative approaches rely on extrinsic vascularization, which is deficient after cancer ablation and irradiation. The aim of the study was to investigate the efficacy of intrinsic axial vascularization of synthetic bone scaffolds in the management of critical-size mandibular defects.

Materials and methods

Scaffold-guided mandibular regeneration in two groups of adult male goats was compared. Only the scaffolds of the second group were axially vascularized via in situ embedding of an arteriovenous loop through microsurgical anastomosis of facial vessels. After 6 months of follow up, both groups were compared through radiological, biomechanical, histological and histomorphometric analysis.

Results

The axially vascularized constructs have showed significantly more central vascularization (p?=?0.021) and markedly enhanced central bone formation (p?=?0.08). The biomechanical characteristics were enhanced, but the difference between both groups was not statistically significant (p?=?0.98).

Conclusions

Axially vascularized synthetic mandibular grafts show better vascularization at their central regions, permitting more efficient bone regeneration.

Clinical relevance

The encouraging results of the proposed technique could be of benefit in optimizing the reconstruction of large critical-size bone defects.     

The biphasic effect of morphine on odor conditioning in neonatal rats.

Three experiments examined the dose-dependent biphasic effect of morphine on odor conditioning in neonatal rats. In Experiment 1, a single pairing of an odor and a low dose of morphine (0.5 mg/kg) in 5-day-old rats produced an odor preference, relative to an unpaired control group. In Experiment 2, pairing an odor with a high dose of morphine (2.0 mg/kg) produced an odor aversion, relative to an unpaired control group. A third experiment compared performance of a group given odor and morphine (2.0 mg/kg) paired to that of two unpaired groups: one given morphine 24 hr prior to and the other 24 hr after odor exposure. The paired group showed an odor aversion relative to both of the unpaired groups, which did not differ. The latter finding suggests that even if morphine metabolism is incomplete after 24 hr, behavior is unaffected. These results are discussed in reference to the functional development of the opioid system in rats.     

Carbamazepine as an adjunct of antipsychotic therapy

The effect of low-dose haloperidol combined with the anticonvulsant carbamazepine was investigated in a 5-week placebo-controlled, double-blind study in acute schizophrenic patients. Weekly ratings showed a clinically pronounced and statistically significant improvement in both the carbamazepine and placebo groups. However, the patients on carbamazepine needed less neuroleptic and anticholinergic medication and experienced fewer side effects compared to the patients on placebo. Moreover, patients in the carbamazepine group showed a clear deterioration after discontinuation of carbamazepine (but maintenance of neuroleptic medication), while the placebo group did not change after discontinuation of placebo. Concomitant treatment with carbamazepine in psychotic patients may help to reduce neuroleptic dosages and unwanted side effects.     

Lymphangioleiomyomatosis: Recurrence after single lung transplantation

Lymphangioleiomyomatosis (LAM) is a rare disease which afflicts young women of childbearing age. Recently, it has been listed as an indication for lung transplantation. We describe a case of recurrent LAM in a 31-year-old woman occurring in the allograft of a male donor after single lung transplantation. Nonisotopic in situ hybridization shows that the smooth muscle cell proliferation is of donor origin.     

The time course of GABA action on the crayfish stretch receptor: evidence for a saturable GABA uptake

The conductance increase induced by bath application of GABA has been measured in voltage-clamped stretch-receptor neurones of crayfish. A rapid conductance increase was obtained only at GABA concentrations above 3.3 X 10(-4) M. The response to lower GABA concentrations (between 10(-4) and 10(-6) M) developed slowly over 30-60 min. Repetitive application of intermediate GABA concentrations induced postsynaptic conductance changes which were progressively enhanced in their onset and magnitude. In the presence of nipecotic acid or in Na+-free Ringer solutions, the response to all GABA concentrations was rapid and constant for each concentration. The time course of inhibitory postsynaptic currents was unaffected by nipecotic acid. These results suggest the presence of a saturable GABA uptake system which limits the access of bath-applied GABA to postsynaptic receptors. This system has little if any effect on the termination of response to synaptically released GABA.