Analysis of social networks among physicians employed at a medical school.

Social network analysis is a well-known method for discovering the social complexities of relationships. In this paper, we present the results of its application in a healthcare environment, i.e. a state university hospital. The sociometric method was adopted to collect social network data. The analysis was performed using Pajek. The medical practice/academic and technological networks among physicians of a state university hospital were explored. Monomorphic and polymorphic opinion leaders (OLs) within the networks were identified using the in-degree measure. Cohesiveness were investigated based on network density and average degree. In addition, it was checked if the mentor system may present impact on the formation of social networks among physicians.

Evaluation of the usability of a serious game aiming to teach facial expressions to schizophrenic patients.

In some psychological disorders such as autism and schizophrenia, loss of facial expression recognition skill may complicate patient's daily life. Information technology may help to develop facial expression recognition skill by educational software and games. We designed and developed an interactive web-based educational program with which we performed a usability study before investigating its effectiveness on the schizophrenia patients' ability of emotion perception. The purpose of this study is to describe the usability evaluation for a web-based game set that has been designed to teach facial expressions to schizophrenic patients. The usability study was done at two steps; first, we applied heuristic evaluation and the violations were rated in a scale from most to least severe and the major problems were solved. In the second step, think-aloud method was used and the web site was assessed by five schizophrenic patients. Eight experts participated in the heuristic evaluation, in which a total of 60 violations were identified with a mean severity of 2.77 (range: 0-4). All of the major problems (severity over 2.5) were listed and the usability problems were solved by the development team. After solving the problems, five users with a diagnosis of schizophrenia used the web site with the same scenario. They reported to have experienced minor, but different problems. In conclusion, we suggest that a combination of heuristic evaluation and think-aloud method may be an effective and efficient way for usability evaluations for the serious games that have been designed for special patient groups.

A random-pattern skin-flap model in streptozotocin diabetic rats.

BACKGROUND: Flap operations are frequently performed in diabetic patients. Nevertheless, we could find no experimental study examining diabetes mellitus's effect on the flaps' survival. For this reason, we designed this study as a random-pattern skin-flap model of diabetic rats in 1999. METHODS: We used 72 rats weighing about 200 g each. The animals were divided into 2 groups, 1 experimental (diabetic) and 1 control (nondiabetic). Following their diabetic periods, we elevated the rats' modified McFarlane flaps and measured their viable flap areas. RESULTS: The mean percentage of the flap area surviving was 51.40% in the 2-week experimental group. It was 48.20% in the 4-week experimental group and 36.70% in the 8-week experimental group. The mean percentage of flap area surviving was 65.87% in the united control group (the total of all control groups). The mean surviving skin-flap area in the united control group was significantly higher than in the 4- and 8-week experimental groups. Moreover, the mean surviving flap area in the 8-week experimental group was significantly lower than in the 2-week and 4-week experimental groups. CONCLUSIONS: Our study demonstrated that a 4-week diabetic duration for rats is sufficient to observe diabetes' deleterious effects on the flaps' viability. These effects were significantly established, however, after 8 weeks of diabetes. To obtain definitive results, at least 8 weeks of diabetic duration are preferred for similar studies.

Effect of experimental varicocele in rats on testicular oxidative stress status.

The present experiments were undertaken to determine the levels of MDA, SOD and catalase in the testis of adolescent rats with experimental left varicoceles. Male Wistar rats, 7 weeks old and weighing 160-170 g, were randomly allocated into three groups. The first group of rats underwent partial ligation of the left renal vein (n = 15). The second group of rats underwent a sham operation (n = 7) and the third group acted as controls (n = 7). Animals were sacrificed 6 weeks after surgery and dilatation of the internal spermatic veins was observed. Levels of MDA, SOD and catalase activity were measured in testis. The experimental left varicocele group showed severe testicular changes compared to other groups. The mean MDA (SEM) levels in right and left testicular tissues of varicocele bearing rats, sham-operated rats, and control rats were 0.48 +/- 0.24 and 0.31 +/- 0.11, 0.22 +/- 0.02 and 0.35 +/- 0.12, 0.62 +/- 0.29 and 0.13 +/- 0.05, respectively (P > 0.05). The mean SOD (SEM) levels in right and left testicular tissues of varicocele bearing rats, sham-operated rats, and control rats were 7,790 +/- 606 and 6,974 +/- 574, 7,475 +/- 1,517 and 7020 +/- 1,106, 8,727 +/- 1,188 and 9,019 +/- 1,129, respectively (P > 0.05). The mean catalase (SEM) levels in right and left testicular tissues of varicocele bearing rats,sham-operated rats, and control rats were 75.77 +/- 11.5 and 53.82 +/- 10.1, 91.94 +/- 14 and 94.90 +/- 32, 65.40 +/- 5.7 and 90.93 +/- 16.4, respectively (P > 0.05). Our results suggest that oxidative status, which reflects a relative balance between reactive oxygen species (ROS) generated and ROS scavenged, may not be responsible for the testicular dysfunction associated with experimentally induced varicocele during adolescence in rats.

Stratification of penile vascular pathologies in patients with Peyronie's disease and in men with erectile dysfunction according to age: a comparative study.

PURPOSE: Erectile dysfunction (ED) occurs in 20% to 54% of men with Peyronie's disease (PD). We investigated the role of vascular status in the pathophysiology of ED in patients with PD. MATERIALS AND METHODS: A total of 509 consecutive men with PD (group 1--impotent 259, 1a, and potent 250, 1b, mean age +/- SD 54.6 +/- 4.4 years) and 507 consecutive men with ED only (group 2--mean age 49.4 +/- 12.4 years) underwent penile duplex ultrasonography (PDU). Detailed sexual and medical history, and focused physical examination were performed in all patients. Patients in the 2, groups were stratified according to age (18 to 80 years) and classified according to PDU results (normal vascular status, arterial insufficiency, veno-occlusive dysfunction [VOD] and mixed vascular pathology). RESULTS: VOD was observed in 23.1% and 42.8% of patients in groups 1 and 2, respectively (p <0.05). Although VOD was significantly more common in group 2 (ED alone) than in group 1a (PD plus ED) in the third decade (p <0.05), overall PDU results showed no statistical difference for VOD between these 2 groups (p >0.05). Of note, mixed vascular pathologies were significantly higher in group 1a than in group 2 in the third through fifth decades (p <0.05), while arterial insufficiency was more common in the seventh decade (p <0.05). CONCLUSIONS: While many groups have investigated the vascular causes of ED, the exact etiology of ED in men with PD remains controversial. A possible relationship between ED and VOD in patients with PD has been previously reported. The current PDU study demonstrates that for all ages except 30 to 39 years the prevalence of VOD in patients with PD plus ED is similar to that of patients with ED alone.

Apoptotic and proliferative index after Alpha-1-adrenoceptor antagonist and/or finasteride treatment in benign prostatic hyperplasia.

INTRODUCTION: The induction of apoptosis has emerged as a potential target for optimization of the medical management of benign prostatic hyperplasia (BPH), recently. The influence of alpha1-adrenoceptor antagonist (alpha1-ARA), 5-alpha reductase inhibitor and their combination on prostatic cell apoptotic and proliferative indices of benign hyperplastic prostate gland were investigated. MATERIALS AND METHODS: A total of 49 male patients with BPH (mean age: 66.5 years) treated with alpha1-ARA and/or finasteride were retrospectively evaluated. Patients treated with alpha1-ARA (doxazosin n = 12 and terazosin n = 10), finasteride (n = 9) and combination of finasteride and alpha1-ARA (n = 9) were enrolled in the study. Primary antibodies were Ki-67 and proliferating cell nuclear antigen for the evaluation of proliferation in prostate stromal and epithelial cells. In situ apoptotic DNA fragmentation was evaluated using TUNEL assay. RESULTS: All treatment groups had no significant changes in the rate of prostate stromal and epithelial cell proliferation. Epithelial apoptotic index (AI) was not statistically significant for finasteride vs. alpha1- ARA, alpha1-ARA vs. finasteride + alpha1-ARA and finasteride + alpha1-ARA vs. finasteride groups. While alpha1-ARA was more effective than finasteride on stromal apoptosis, alpha1-ARA-induced stromal apoptosis was not significantly different from alpha1-ARA plus finasteirde treatment. CONCLUSION: Not only androgen variabilities but also alterations in sympathetic neurotransmission with age could have important implications for pathophysiological prostate growth. The combination of finasteride and alpha1-ARA is not superior to alpha1-ARA therapy with their similar epithelial and stromal apoptotic effects with unaffected cell proliferation.