Platelet activation status decreases after menopause

Objective.?The aim of the study was to investigate the impact of the climacterium (before and after menopause) on platelet activation.

Background.?Platelet activation has been associated to the risk of cardiovascular disease. There is much speculation about the relationship between platelet function and sex steroids, due to peculiarities of platelet action between the genders, including concerns about the influence of low estradiol status in menopausal women.

Methods.?By means of a cross-sectional study design, 37 female patients divided into two groups were compared. Group A consisted of ten women, mean age 43.9 years, in the premenopausal period, with normal estrogen levels; and Group B comprised 27 patients, mean age 53.0 years, who had all reached menopause. Platelet activation markers, namely P-selectin and glycoprotein IIb–IIIa complex (GPIIb–IIIa), were evaluated by flow cytometry with monoclonal antibodies. A binding index was calculated for both parameters (percentage of positive platelets?×?mean fluorescence of positive platelets). Also, thromboxane A₂ was quantified by means of its main plasma metabolite, thromboxane B₂, by enzyme immunoassay.

Results.?P-selectin and GPIIb–IIIa expression results revealed lower platelet activation status after menopause, as there was a decrease in both the percentage of P-selectin^?+? platelets and of GPIIb–IIIa mean fluorescence of positive platelets, lowering both binding indices. P-selectin binding index differed significantly between Group A (12.3?±?3, n?=?10) and Group B (6.2?±?2.9, n?=?27; mean?±?standard deviation (SD), p?<?0.001). GPIIb–IIIa binding index also differed significantly between both groups (Group A: 18.8?±?2.3, n?=?10 vs. Group B: 16.2?±?3.1, n?=?27; mean?±?SD, p?<?0.0018). Plasma concentration of thromboxane B₂ was 1.07?±?0.5?pg/well before menopause (Group A, n?=?10) and 1.9?±?4.1?pg/well after menopause (Group B, n?=?27), not significantly different (mean?±?SD, baseline?×?therapy, p?=?0.85).

Conclusions.?After the menopause, climacteric women – whose estradiol status is low – have a decreased activation platelet status compared with premenopausal women. Nevertheless, further studies on a larger sample are necessary for conclusive data regarding cardiovascular disease.     

Biomarkers for traumatic brain injury: a short review

Neurosurgical Review - Cellular response to TBI is a mixture of excitotoxicity, neuroinflammation, and cell death. Biomarkers that can track these lesions and inflammatory processes are being...     

Correlación entre la expresión del receptor dopaminérgico D2 y presencia de movimientos involuntarios anormales (MIA) en un modelo de disquinesia en ratas Wistar hemiparkinsonizadas

Parkinson's disease (PD) is characterised by motor alterations, which are commonly treated with L-DOPA. However, long-term L-DOPA use may cause dyskinesia. Although the pathogenic mechanism of L-DOPA-induced dyskinesia is unclear, the condition has been associated with alterations in dopamine receptors, among which D2 receptors (D2R) have received little attention. This study aims to: (i) develop and standardise an experimental model of L-DOPA-induced dyskinesia in rats with hemiparkinsonism; and (ii) evaluate the correlation between D2R expression and presence of abnormal involuntary movements (AIM). We allocated 21 male Wistar rats into 3 groups: intact controls, lesioned rats (with neurotoxin 6-OHDA), and dyskinetic rats (injected with L-DOPA for 19 days). Sensorimotor impairment was assessed with behavioural tests. Dyskinetic rats gradually developed AIMs during the treatment period; front leg AIMs were more severe and locomotor AIMs less severe (P < .05). All AIMs were significantly evident from day 5 and persisted until the last day of injection. D2R density was greater in the striatum and the medial anterior brain of the lesioned and dyskinetic rats than in those of controls. Our results suggest an association between D2R expression and locomotor AIMs. We conclude that RD2 is involved in L-DOPA-induced dyskinesia.     

Bereitschaftspotential preceding spontaneous and voluntary eyelid blinks in normal individuals

Objective

To investigate the Bereitschaftspotential (BP) preceding spontaneous and voluntary eyelid blinks in normal subjects.

Atypical presentation in Rasmussen encephalitis: delayed late-onset periodic epileptic spasms

A five-and-a-half-year-old girl started experiencing progressive left hemiparesis at age two and a half years. At age five years and four months she started presenting clusters of asymmetric periodic epileptic spasms with no hypsarrhythmia. The ictal EEG showed periodic, constant and stereotyped complexes. Serial brain imaging revealed progressive atrophy of the right hemisphere with increased T2 signal on MRI. She underwent a right hemispherotomy, and histological examination showed signs of inflammation and features of focal cortical dysplasia (FCD). She has been seizure-free for 16 months. This case is unique in the following aspects: the presence of typical Rasmussen encephalitis features of progressive unilateral brain involvement without seizures, a delay of almost three years prior to seizure onset; an atypical seizure type presentation with periodic epileptic spasms and the presence of FCD associated with inflammatory changes. [Published with video sequences].     

Hydrocephalus in neurocysticercosis

Introduction  

Cysticercosis (CC) is the most important of the parasitic diseases of the central nervous system due to its high incidence in the world. CC is the infection with the larval cysts of Taenia solium. It is the most common helminthic infection of the nervous system and is endemic in most underdeveloped countries as well as in industrialized nations. It is estimated that approximately 50,000 people die every year from neurocysticercosis (NCC) worldwide.