Nanoscopic insights into the surface conformation of neurotoxic amyloid β oligomers

Raman spectroscopy assisted by localized plasmon resonances generating effective hot spots at the gaps between intertwined silver nanowires is herein adopted to unravel characteristic molecular motifs on the surface of Aβ₄₂ misfolded oligomers that are critical in driving intermolecular interactions in neurodegeneration.

Unraveling characteristic structural determinants at the basis of Aβ₄₂ oligomers'' neurotoxicity by a sub-molecular SERS investigation of their surface.     

Síndrome de hipoglucemia por hiperinsulinismo endógeno: tratamiento quirúrgico

Background

The endogenous hyperinsulinemic hypoglicemia syndrome (EHHS) can be caused by an insulinoma, or less frequently, by nesidioblastosis in the pediatric population, also known as non insulinoma pancreatic hypoglycemic syndrome (NIPHS) in adults.The aim of this paper is to show the strategy for the surgical treatment of ehhs.

Material and methods

A total of 19 patients with a final diagnosis of insulinoma or NIPHS who were treated surgically from january 2007 until june 2012 were included. We describe the clinical presentation and preoperative work-up. Emphasis is placed on the surgical technique, complications and long-term follow-up.

Results

All patients had a positive fasting plasma glucose test. Preoperative localization of the lesions was possible in 89.4% of cases. The most frequent surgery was distal pancreatectomy with spleen preservation (9 cases). Three patients with insulinoma presented with synchronous metastases, which were treated with simultaneous surgery. There was no perioperative mortality and morbidity was 52.6%. Histological analysis revealed that 13 patients (68.4%) had benign insulinoma, 3 malignant insulinoma with liver metastases and 3 with a final diagnosis of SHPNI. Median follow-up was 20 months. All patients diagnosed with benign insulinoma or NIPHS had symptom resolution.

Conclusion

The surgical treatment of EHHS achieves excellent long-term results in the control of hypoglucemic symptoms.     

The distribution of the jejunal arteries in the cat

The arterial supply of the cat jejunum was studied by gross dissection and polyurethane corrosion cast. The results showed that the jejunal arteries, which originate from the cranial mesenteric artery, varied from 5 to 15 in number. Their number was independent of the length of the cranial mesenteric artery as well as of the length of the jejunum. These arteries divided into branches giving rise to a series of orders of division from a minimum of 1 to a maximum of 7. The last orders of division terminated in a series of anastomosing arcades which resulted in a marginal artery coursing only a few millimeters from the mesenteric margin of the jejunum. This artery gave rise to straight arteries (vasa recta), whose mean number was 450 ± 60. According to their length, the vasa recta can be differentiated into short (vasa brevia) and long (vasa longa) branches. The vasa brevia ended branching into the mesenteric side of the jejunum whereas the vasa longa coursed beneath the serosa on the lateral jejunal surfaces, and reached the antimesenteric border. During their course, the vasa recta ramified and anastomosed with each other. Numerous antimesenteric anastomoses between opposing vasa longa were also observed. Based on the literature consulted, due to the large number of vasa recta (approximately one vessel per 2.9 mm of jejunal length) and the rich anastomotic network, the cat jejunum might have a better intramural distribution of blood flow and would seem less predisposed to ischemic phenomena than that of other mammals.     

Functional anatomy of 5-HT2A receptors in the amygdala and hippocampal complex: relevance to memory functions

The amygdaloid complex and hippocampal region contribute to emotional activities, learning, and memory. Mounting evidence suggests a primary role for serotonin (5-HT) in the physiological basis of memory and its pathogenesis by modulating directly the activity of these two areas and their cross-talk. Indeed, both the amygdala and the hippocampus receive remarkably dense serotoninergic inputs from the dorsal and median raphe nuclei. Anatomical, behavioral and electrophysiological evidence indicates the 5-HT_2A receptor as one of the principal postsynaptic targets mediating 5-HT effects. In fact, the 5-HT_2A receptor is the most abundant 5-HT receptor expressed in these brain structures and is expressed on both amygdalar and hippocampal pyramidal glutamatergic neurons as well as on γ-aminobutyric acid (GABA)-containing interneurons. 5-HT_2A receptors on GABAergic interneurons stimulate GABA release, and thereby have an important role in regulating network activity and neural oscillations in the amygdala and hippocampal region. This review will focus on the distribution and physiological functions of the 5-HT_2A receptor in the amygdala and hippocampal region. Taken together the results discussed here suggest that 5-HT_2A receptor may be a potential therapeutic target for those disorders related to hippocampal and amygdala dysfunction.     

Effectiveness of anesthetic solutions for pain control in lower third molar extraction surgeries: a systematic review of randomized clinical trials with network meta-analysis

Clinical Oral Investigations - To assess the effectiveness of different anesthetic solutions for pain control immediately after the extraction of lower third molars. Nine databases were used to...