Analysis of the effect of the scorpion toxin AaH-II on action potential generation in the axon initial segment.

The toxin AaH-II, from the scorpion Androctonus australis Hector venom, is a 64 amino acid peptide that targets voltage-gated Na channels (VGNCs) and slows their inactivation. While at macroscopic cellular level AaH-II prolongs the action potential (AP), a functional analysis of the effect of the toxin in the axon initial segment (AIS), where VGNCs are highly expressed, was never performed so far. Here, we report an original analysis of the effect of AaH-II on the AP generation in the AIS of neocortical layer-5 pyramidal neurons from mouse brain slices.

Six different extremely calcified lesions of the brain: brain stones.

Background: This study aimed to extend clinical documentation of cerebral calculi by reporting six cases of cerebral calculi with distinct etiologies and localizations.

Methods: We evaluated the age, sex distribution, presenting symptoms, neurological examination findings, pathology results, and location of the calcifications of six patients with intracranial calcifications.

Results: Three of the six patients with brain stones were female (50%), and three were male (50%).

Noninvasive pressure support ventilation in patients with acute respiratory failure. A randomized comparison with conventional therapy.

The benefit of noninvasive pressure support ventilation (NIPSV) in avoiding the need for endotracheal intubation and reducing morbidity and mortality associated with endotracheal intubation was evaluated in 41 patients who presented with acute respiratory failure not related to chronic obstructive pulmonary disease (COPD). Patients were randomly assigned to receive conventional therapy (n = 20) or conventional therapy plus NIPSV (n = 21). NIPSV was delivered to the patient by a face mask connected to a ventilator (Puritan-Bennett 7200a) set in inspiratory pressure support (IPS) mode.

Noninvasive pressure support ventilation in patients with acute respiratory failure.

To further delineate indications for noninvasive pressure support ventilation (NIPSV), we proposed this noninvasive technique as an alternative to endotracheal intubation in 17 consecutive patients with acute respiratory failure from various causes. Eight patients (47 percent) were successfully ventilated with NIPSV, while in 9 (53 percent), NIPSV failed. Gas exchange values before initiating NIPSV were different between the 2 groups: patients successfully ventilated with NIPSV had a higher PaCO2 (57 +/- 15 mm Hg vs 37 +/- 17 mm Hg; p = 0.