Effects of the oral, direct factor xa inhibitor rivaroxaban on platelet-induced thrombin generation and prothrombinase activity

Rivaroxaban (BAY 59-7939) is an oral, direct factor Xa inhibitor in advanced development. This study was undertaken to investigate its effects on thrombin generation. In this placebo-controlled, randomized, crossover study, 12 healthy subjects received rivaroxaban (single 5- or 30-mg dose) or placebo. Thrombin generation was investigated by measuring the endogenous thrombin potential and prothrombinase-induced clotting time. Maximal effect of rivaroxaban was observed 2 hours after drug administration: prothrombinase-induced clotting time was prolonged 1.8 and 2.3 times baseline after rivaroxaban 5 and 30 mg, respectively. Collagen-induced endogenous thrombin potential was reduced by approximately 80% and approximately 90% compared with baseline after rivaroxaban 5 and 30 mg, respectively, and tissue factor-induced endogenous thrombin potential was reduced by approximately 40% (5 mg) and approximately 65% (30 mg), respectively. Thrombin generation remained inhibited for 24 hours. There was a close correlation between plasma concentration of rivaroxaban and prolongation of prothrombinase-induced clotting time and reduction in endogenous thrombin potential. Rivaroxaban strongly inhibits platelet-induced thrombin generation, after activation of either platelets or the coagulation pathway, even in the presence of minimal factor Xa inhibition in plasma.     

Ten-year clinical performance of non-precious metal double crowns with friction pins in severely reduced dentitions—a retrospective study

Clinical Oral Investigations - This follow-up study aimed at collecting long-term data for removable partial dentures (RPDs) retained by double crowns with spark-eroded friction pins (DCP) and...     

Short-lasting impairment of temperature perception by high frequency rTMS of the sensorimotor cortex.

OBJECTIVE: Repetitive transcranial magnetic stimulation (rTMS) has become a useful tool for investigating and even modulating human brain function. RTMS of the human motor cortex can produce changes in excitability that outlast the period of stimulation. To investigate the persistent effect of high-frequency rTMS of sensorimotor cortex (SM1) on somatosensory function. METHODS: We evaluated the thermal thresholds (cold and warm sensation) in 14 normal subjects before and after a short train of 5Hz rTMS over the SM1 or occipital cortex (OC). RESULTS: Threshold for cold perception was increased immediately after rTMS of the left SM1 and no effects at all were noticed after OC stimulation. There was a slight, not significant, increase of warm threshold immediately after the rTMS of the left SM1 and no effects at all were noticed after OC stimulation. CONCLUSIONS: High frequency rTMS over primary sensorimotor cortex seems to modulate sensory function related to thermal (cold) perception. SIGNIFICANCE: The method may be useful for both the study of normal human physiology of temperature perception and for rTMS based manipulation of brain plasticity in patients with sensory disturbances.     

SALUS—a non-inferiority trial to compare self-tonometry in glaucoma patients with regular inpatient intraocular pressure controls: study design and set-up

Graefe's Archive for Clinical and Experimental Ophthalmology - The SALUS study aims to improve the healthcare situation for glaucoma patients in Germany. In order to detect diurnal intraocular...     

PET–CT vs. CT alone in ovarian cancer recurrence

Background To compare fusion, positron emission tomography–computed tomography (PET–CT) with CT alone in detecting ovarian carcinoma recurrence. Methods Fifty-one consecutive patients underwent 53 restaging PET–CT scans with a concurrent diagnostic quality CT scan. Two body imaging radiologists independently assessed the CT’s; each then teamed with a nuclear medicine specialist to review the PET–CT’s. Two teams conferred for consensus on the presence of disease in the chest, abdomen, and body overall with CT alone and with PET–CT, using a six-point reader confidence metric to determine accuracy and receiver operating characteristic (ROC) curves. Reader agreement was compared using kappa. Recurrence was determined by two gynecologic oncologists reviewing clinical records from time of presentation to at least 13 months (mean 22.7) after imaging. Results Recurrence was based on histopathology in 17% (9/53). Seventy-two percent (38/53) cases had recurrence, with two cases showing isolated chest recurrence. PET–CT accuracy exceeded CT for body 92% (49/53) vs. 83% (44/53), chest 96% (51/53) vs. 89% (47/53), and abdomen 91% (48/53) vs. 79% (42/53). ROC curves for PET–CT dominated that for CT alone; this difference was statistically significant for abdomen and for body overall (P < 0.01). Interobserver agreement was better for PET–CT than for CT alone. Conclusions PET–CT demonstrates greater accuracy and less interobserver variability than CT alone.     

Attentional capture in multiple object tracking

Attentional processes are generally assumed to be involved in multiple object tracking (MOT). The attentional capture paradigm is regularly used to study conditions of attentional control. It has up to now not been used to assess influences of sudden onset distractor stimuli in MOT. We investigated whether attentional capture does occur in MOT: Are onset distractors processed at all in dynamic attentional tasks? We found that sudden onset distractors were effective in lowering probe detection, thus demonstrating attentional capture. Tracking performance as dependent measure was not affected. The attentional capture effect persisted in conditions of higher tracking load (Experiment 2) and was dramatically increased in lower presentation frequency of the onset distractor (Experiment 3). Tracking performance was shown to suffer only when onset distractors were presented serially with very short time gaps in between, thus effectively disturbing re-engaging attention on the tracking set (Experiment 4). We discuss that rapid dis- and re-engagement of the attention process on target objects and an additional more basic process that continuously provides location information allow managing strong disruptions of attention during tracking.     

Accuracy of quantitative coronary angiography with computed tomography and its dependency on plaque composition

Objective: To determine the impact of plaque composition on accuracy of quantitative 64-slice computed tomography coronary angiography (CTCA). Methods: The institutional review board approved this study; written informed consent was obtained from all patients. One hundred consecutive patients (42 women, mean age 64.6 ± 9.4 years, age range 39–87 years) underwent CTCA and invasive quantitative coronary angiography (QCA) to determine (a) the diagnostic accuracy of CTCA for the detection of significant stenosis (diameter reduction of ≥50%), and (b) the accuracy of stenosis grading. In CTCA stenosis severity was graded in 10% steps and evaluated separately for calcified and non-calcified coronary lesions using Pearson-linear-regression analysis, Bland/Altman-analysis (BA), and Mann-Whitney-U-test. Results: In 60/100 patients 139 significant coronary artery stenoses were identified with QCA. On a per-segment analysis, sensitivity of CTCA was 75.5%, and specificity was 96.6% (positive predictive value: 72.9%, negative predictive value: 97.0%). Quantification of stenosis grading correlated moderately between methods (r = 0.60; P < 0.001), with an overestimation by CTCA of 5.5% (BA limits-of-agreement −29 to 39%). BA limits-of-agreement were greater in calcified lesions (−29.2 to 45.6%; mean error 8.2%) than in non-calcified lesions (−25.9 to 30.2%; mean error 2.2%) and differed significantly (P < 0.05). Conclusions: Diagnostic accuracy of CTCA is high, however agreement for quantitative lesion severity assessment between CTCA and QCA is moderate for calcified but superior for non-calcified lesions.