14 research outputs found
Sex differences in discriminating between cues predicting threat and safety
Post-traumatic stress disorder (PTSD) is more prevalent in women than men. PTSD is characterized by overgeneralization of fear to innocuous stimuli and involves impaired inhibition of learned fear by cues that predict safety. While evidence indicates that learned fear inhibition through extinction differs in males and females, less is known about sex differences in fear discrimination and safety learning. Here we examined auditory fear discrimination in male and female rats. In Experiment 1A, rats underwent 1-3 days of discrimination training consisting of one tone predicting threat (CS+; presented with footshock) and another tone predicting safety (CS-; presented alone). Females, but not males, discriminated between the CS+ and CS- after one day of training. After 2-3 days of training, however, males discriminated whereas females generalized between the CS+ and CS-. In Experiment 1B, females showed enhanced anxiety-like behaviour and locomotor activity in the open field, although these results were unlikely to explain the sex differences in fear discrimination. In Experiment 2, we found no differences in shock sensitivity between males and females. In Experiment 3, males and females again discriminated and generalized, respectively, after three days of training. Moreover, fear generalization in females resulted from impaired safety learning, as shown by a retardation test. Whereas subsequent fear conditioning to the previous CS- retarded learning in males, females showed no such retardation. These results suggest that, while females show fear discrimination with limited training, they show fear generalization with extended training due to impaired safety learning
Influence of operative time and blood loss on surgical margins and functional outcomes for laparoscopic versus robotic-assisted radical prostatectomy: a prospective analysis
Introduction: The aim of this article was to analyze whether operative time and blood loss during radical prostatectomy (RP) can significantly influence surgical margins (SM) status and post-operative functional outcomes.
Material and methods: We prospectively analyzed prostate cancer (PC) patients undergoing RP, using robot-assisted (RARP) or laparoscopic (LRP) procedures. Blood loss was defined using the variation in hemoglobin (Hb, g/dl) values from the day before surgery and no later than 4 hours after surgery.
Results: From a whole population of 413 cases considered for RP, 67% underwent LRP and 33.0% RARP. Positive SM (SM+) were found in 33.9% of cases. Mean surgical operative time was 172.3 ±76 min (range 49-485), whereas blood loss was 2.3 ±1.2 g/dl (range 0.3-7.6). Operative time and blood loss at RP were not significantly correlated (r = -0.028275; p = 0.684). SM+ rates significantly (p = 0.002) varied by operative time; a higher SM+ rate was found in cases with an operative time <120 min (41.2%) and >240 min (53.4%). The risk of SM+ significantly increased 1.70 and 1.94 times in cases with an operative time <120 min and >240 min, respectively, independently to the surgical approach. The rate of erectile disfunction (ED) varied from 22.4% to 60.3% between <120 min and >240 min procedures (p = 0.001). According to blood loss, SM+ rates slightly but significantly (p = 0.032) varied; a higher rate of SM+ was found in cases with a Hb variation between 2-4 g/dl (35.9%).
Conclusions: Independently to the surgical approach, operative time, more than blood loss at RP, represents a significant variable able to influence SM status and post-operative ED
The Role of the Hippocampus in Avoidance Learning and Anxiety Vulnerability
The hippocampus has been implicated in anxiety disorders and post-traumatic stress disorder (PTSD); human studies suggest that a dysfunctional hippocampus may be a vulnerability factor for the development of PTSD. In the current study, we examined the effect of hippocampal damage in avoidance learning, as avoidance is a core symptom of all anxiety disorders. First, the effect of hippocampal damage on avoidance learning was investigated in outbred Sprague Dawley (SD) rats. Second, the function of the hippocampus in Wistar-Kyoto (WKY) rats was compared to SD rats. The WKY rat is an animal model of behavioral inhibition, a risk factor for anxiety, and demonstrates abnormal avoidance learning, marked by facilitated avoidance acquisition and resistance to extinction. The results of the current study indicate that hippocampal damage in SD rats leads to impaired extinction of avoidance learning similar to WKY rats. Furthermore, WKY rats have reduced hippocampal volume and impaired hippocampal synaptic plasticity as compared to SD rats. These results suggest that hippocampal dysfunction enhances the development of persistent avoidance responding and, thus, may confer vulnerability to the development of anxiety disorders and PTSD
Influence of operative time and blood loss on surgical margins and functional outcomes for laparoscopic versus robotic-assisted radical prostatectomy: a prospective analysis
Introduction The aim of this article was to analyze whether operative time and blood loss during radical prostatectomy (RP) can significantly influence surgical margins (SM) status and post-operative functional outcomes.Material and methods We prospectively analyzed prostate cancer (PC) patients undergoing RP, using robot-assisted (RARP) or laparoscopic (LRP) procedures. Blood loss was defined using the variation in hemoglobin (Hb, g/dl) values from the day before surgery and no later than 4 hours after surgery.Results From a whole population of 413 cases considered for RP, 67% underwent LRP and 33.0% RARP. Positive SM (SM+) were found in 33.9% of cases. Mean surgical operative time was 172.3 +/- 76 min (range 49-485), whereas blood loss was 2.3 +/- 1.2 g/dl (range 0.3-7.6). Operative time and blood loss at RP were not significantly correlated (r =-0.028275; p = 0.684). SM+ rates significantly (p = 0.002) varied by operative time; a higher SM+ rate was found in cases with an operative time <120 min (41.2%) and >240 min (53.4%). The risk of SM+ significantly increased 1.70 and 1.94 times in cases with an operative time <120 min and >240 min, respectively, independently to the surgical approach. The rate of erectile disfunction (ED) varied from 22.4% to 60.3% between <120 min and >240 min procedures (p = 0.001). According to blood loss, SM+ rates slightly but significantly (p = 0.032) varied; a higher rate of SM+ was found in cases with a Hb variation between 2-4 g/dl (35.9%).Conclusions Independently to the surgical approach, operative time, more than blood loss at RP, represents a significant variable able to influence SM status and post-operative ED