The N-methyl-D-aspartate antagonist memantine retards progression of Huntington's disease

According to the excitotoxicity hypothesis, neurotoxicity due to glutamate is regarded as potential factor in the progredient neurodegeneration of Huntington's disease (HD). Memantine, as a glutamate receptor antagonist, should counteract this mechanism. Its effectiveness (up to 30 mg/day) with regard to retardation of progression was thus examined in 27 HD patients in a two year, open and multicentre trial. The results suggest that memantine treatment of HD may be useful in terms of retardation of the progression of the disorder.     

Glucose metabolism of breast cancer assessed by 18F-FDG PET: histologic and immunohistochemical tissue analysis.

Breast cancer is characterized by elevated glucose consumption resulting in increased uptake of 18F-FDG. However, tracer uptake varies considerably among tumors imaged with PET. This study compared histologic and immunohistochemical tissue analysis of breast carcinomas with preoperative FDG uptake assessed by PET to identify tumor characteristics that define the degree of tracer accumulation. METHODS: FDG uptake in breast tumors was quantified by calculating standardized uptake values (SUVs) corrected for partial-volume effect and normalized to blood glucose level at the time of tracer injection. The histologic sections of 50 invasive and 6 noninvasive breast carcinomas were analyzed for histologic type, microscopic tumor growth pattern, percentage of tumor cells, presence of inflammatory cells, density of blood vessels, histopathologic grading, tumor cell proliferation (mitotic rate and antibody binding of MIB-1), expression of estrogen and progesterone receptors, and expression of the glucose transporter protein Glut-1. RESULTS: A positive correlation was found between FDG uptake and histologic tumor type (ductal vs. lobular; P = 0.003), microscopic tumor growth pattern (nodular vs. diffuse; P = 0.007), and tumor cell proliferation (MIB-1; P = 0.009). Tumors with diffuse growth patterns had significantly lower SUVs compared with clearly defined tumors. A weak relationship was found between FDG uptake and the percentage of tumor cells (P = 0.06). Lower densities of blood vessels corresponded to higher FDG uptakes (P = 0.08). However, even significant correlations showed poor correlation coefficients. No relationship was found between FDG uptake and the following: tumor size; axillary lymph node status; percentage of necrotic, fibrotic, and cystic compounds; presence of inflammatory cells; steroid receptor status; and expression of Glut-1. CONCLUSION: Histologic and immunohistochemical tissue analysis was unable to sufficiently explain the variation of FDG uptake in breast cancer. The degree of metabolic changes after malignant transformation is most likely explained by a complex interaction between cellular energy demand and tumoral microenvironment. Therefore, FDG PET imaging may not be used to estimate tumor biologic behavior of breast cancer such as differentiation, histopathologic grading, cell proliferation, or axillary lymph node status.     

Simultaneous and Differential Fronto-orbital and Midface Distraction Osteogenesis for Syndromic Craniosynostosis Using Rigid External Distractor II

ABSTRACT: In syndromic craniosynostosis, the relation between the supraorbital area and the frontal bone is not good, and it is not possible to reform this area with 1-block advancement. To avoid this problem, the frontal bone is separated from the fronto-orbital bandeau, each is reshaped and remodeled separately, and then both are reattached.The retrusion of the midface, especially in syndromic craniosynostosis, is usually greater than that of cranial bones, so the technique usually separating the midface from the cranium is Le Fort III osteotomy, which allows differential distraction of each part.In this procedure, the cranial and midfacial bones are advanced simultaneously and differentially, both to the planned extent, in a single-stage operation, using rigid external distractor II, correcting exorbitism, respiratory embarrassment, and cranial structures and avoiding eye complications in the future. This procedure was used, with a follow-up, in 10 patients with syndromic craniosynostosis from 2 to 5 years.     

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.