Localized APP expression results in progressive network dysfunction by disorganizing spike timing.

Progressive cognitive decline in Alzheimer's disease could either be caused by a spreading molecular pathology or by an initially focal pathology that causes aberrant neuronal activity in a larger network. To distinguish between these possibilities, we generated a mouse model with expression of mutant human amyloid precursor protein (APP) in only hippocampal CA3 cells. We found that performance in a hippocampus-dependent memory task was impaired in young adult and aged mutant mice. In both age groups, we then recorded from the CA1 region, which receives inputs from APP-expressing CA3 cells. We observed that theta oscillation frequency in CA1 was reduced along with disrupted relative timing of principal cells. Highly localized pathology limited to the presynaptic CA3 cells is thus sufficient to cause aberrant firing patterns in postsynaptic neuronal networks, which indicates that disease progression is not only from spreading pathology but also mediated by progressively advancing physiological dysfunction.

Association of Thyroid Profile and Prolactin Level in Patient with Secondary Amenorrhea

Background: Amenorrhea is the absence of menstrual periods. It has multiple social consequences as it may leads to infertility. This case control study was conducted for determining the association of thyroid hormones with hyperprolactinemia in patient with amenorrhea. Methods: We investigated 50 women with diagnosed cases of secondary amenorrhoea, who attended UCMS hospital, for hormonal evaluations. Fifty two healthy women were taken as the controls. The thyroid dysfunction and serum prolactin level were reviewed in cases and in the controls. Results: Mean serum prolactin level was found to be significantly higher in the cases as compared to the controls. Mean serum fT3 and fT4 level in the hyperprolactinemic cases (mean = 2.67, SD = 1.04 pg/ml) and (mean = 1.38, SD = 0.51 ng/dl respectively) were slightly lower as compared to normoprolactinemic cases (mean = 3.21, SD = 1.86 pg/ml) and (mean = 1.73, SD = 1.37 ng/dl) respectively. Mean TSH of normoprolactinemic and hyperprolactinemic cases were comparable (P = 0.049). There was positive correlation between prolactin, BMI and TSH whereas negative correlation of prolactin was seen with fT3, fT4 and age. In hyperprolactainemic cases, prolactin was found to be negatively correlated with TSH (r = -0.155, P = 0.491) whereas prolactin was positively correlated with TSH (r = 0.296, P = 0.126) in normoprolactainemic cases. Conclusions: Thus, hyperprolactinemia with thyroid dysfunction may be contributory hormonal factor in patient with amenorrhoea and as such, estimation of prolactin, fT3, fT4 and TSH should be included for diagnostic evaluation of amenorrhea.

Bleeding outcomes after routine transradial primary angioplasty for acute myocardial infarction using eptifibatide and unfractionated heparin: a single-center experience following the HORIZONS-AMI trial.

OBJECTIVES: We sought to (1) determine the bleeding rates after primary percutaneous coronary intervention (PPCI) in our institution, where the default strategy has been transradial (TR) access in combination with unfractionated heparin (UFH) plus eptifibatide, and (2) compare these with the outcomes of patients treated with bivalirudin in HORIZONS-AMI. BACKGROUND: HORIZONS-AMI demonstrated that in PPCI undertaken via the transfemoral route, routine use of bivalirudin was associated with lower bleeding rates and improved mortality compared to routine use of UFH plus glycoprotein IIb/IIIa inhibitor (GPI). METHODS: This was a single-center prospective registry of consecutive patients undergoing PPCI from January 2009 to August 2011 at the Queen Elizabeth Hospital Birmingham, UK. Thirty-day major bleeding was defined as per the HORIZONS-AMI criteria and also according to TIMI and GUSTO scales. RESULTS: Of the 432 consecutive patients, 350 fulfilled entry criteria for HORIZONS-AMI. In contrast with HORIZONS-AMI, these subjects were older (62.5 ± 13.7 yr vs. 59.8 ± 11.1 yr, P < 0.05) with a higher rate of cardiogenic shock (6.3% vs. 0.8%, P < 0.0001). Despite this higher risk population, the rate of major bleeding was favorable (3.7% [95% CI: 2.0-6.3%] vs. 4.9% [4.0-6.1%], P = 0.32). Similarly, TIMI major bleeding (2.0% [0.8-4.1%] vs. 3.1% [2.3-3.4%], P = 0.10) and GUSTO severe or life-threatening bleeding (0.6% [0.1-2.5%] vs. 0.4% [0.2-0.9%], P = 0.75) were comparable. CONCLUSIONS: Routine TR access for PPCI using UFH plus GPI is associated with a low 30-day rate of major bleeding equivalent to the bivalirudin arm of HORIZONS-AMI. Default transradial access for PPCI permits routine use of a GPI without the penalty of high bleeding rates.