Infectious Microorganisms Seen as Etiologic Agents in Parkinson's Disease.

Infections represent a possible risk factor for parkinsonism and Parkinson's disease (PD) based on information from epidemiology and fundamental science. The risk is unclear for the majority of agents. Moreover, the latency between infection and PD seems to be very varied and often lengthy. In this review, the evidence supporting the potential involvement of infectious microorganisms in the development of Parkinson's disease is examined. Consequently, it is crucial to determine the cause and give additional treatment accordingly. Infection is an intriguing suggestion regarding the cause of Parkinson's disease. These findings demonstrate that persistent infection with viral and bacterial microorganisms might be a cause of Parkinson's disease. As an initiating factor, infection may generate a spectrum of gut microbiota dysbiosis, engagement of glial tissues, neuroinflammation, and alpha-synuclein accumulation, all of which may trigger and worsen the onset in Parkinson's disease also contribute to its progression. Still uncertain is the primary etiology of PD with infection. The possible pathophysiology of PD infection remains a matter of debate. Furthermore, additional study is required to determine if PD patients develop the disease due to infectious microorganisms or solely since they are more sensitive to infectious causes.

Impact of Training on Three-Dimensional versus Two-Dimensional Laparoscopic Systems on Acquisition of Laparoscopic Skills in Novices: A Prospective Comparative Pilot Study.

In this prospective educational study, 10 medical students (novices) were randomized to practice two basic laparoscopic tasks from the MISTELS program, namely, Pegboard Transfer (PT) and Intracorporeal Knot Tying (IKT) tasks, using either a 2D or a 3D laparoscopic platform. There was no significant difference between both groups in the baseline assessments (PT task: 130.8 ± 18.7 versus 151.5 ± 33.4; p = 0.35) (IKT task: 123.9 ± 41.0 versus 122.9 ± 44.9; p = 0.986). Following two training sessions, there was a significant increase in the scores of PT task for the 2D (130.8 ± 18.7 versus 222.6 ± 7.0; p = 0.0004) and the 3D groups (151.5 ± 33.4 versus 211.7 ± 16.2; p = 0.0001). Similarly, there was a significant increase in the scores of IKT task for the 2D (123.9 ± 41.0 versus 373.3 ± 47.2; p = 0.003) and the 3D groups (122.9 ± 44.9 versus 338.8 ± 28.6; p = 0.0005). However, there was no significant difference in the final assessment scores between 2D and 3D groups for both tasks (p > 0.05). Therefore, 3D laparoscopic systems do not provide an advantage over 2D systems for training novices in basic laparoscopic skills.

Incorporation of the da Vinci Surgical Skills Simulator at urology Objective Structured Clinical Examinations (OSCEs): a pilot study.

INTRODUCTION: To incorporate the da Vinci Surgical Skills Simulator (dVSSS) into Objective Structured Clinical Examinations (OSCEs) and to assess basic robotic skills of urology Post-Graduate Trainees (PGTs). MATERIALS AND METHODS: PGTs in post-graduate years (PGY-3 to PGY-5) from two Quebec urology training programs were recruited. During a 20 minute OSCE station, PGTs were asked to fill in a questionnaire and perform two tasks: pick and place, and energy dissection level 1. For each exercise, the norm-referenced method was used to establish a passing score to determine competency. The participant was considered competent in these two basic dVSSS exercises if he/she gained the passing score on both tasks. RESULTS: All nine PGTs who attended the OSCE voluntarily participated in the study. They had performed a median of 10 (IQR: 2.5-16) laparoscopic procedures, 2 (0-8) robotic procedures, and assisted 10 (IQR: 0-15) robotic procedures at the bedside prior to this OSCE. Based on a passing score of 90 for task 1 and 72 for task 2, there were 3 (33%) competent PGTs, all of whom were from PGY-5 level. Therefore, there was significant difference among PGY levels in terms of competency for the basic robotic skills tested (p = 0.01). When compared with PGTs, experts had performed significantly higher numbers of robotic procedures (5.2 +/- 2.4 versus 25 +/- 8.7; p = 0.02). However, there was no significant difference in the performance parameters between PGTs and experts in both tasks. CONCLUSION: This study confirms the feasibility of incorporating dVSSS into OSCEs to assess basic robotic skills of urology PGTs. Future studies need to include more complex exercises and larger sample size to expand on these results.

Modeling epidemics on adaptively evolving networks: A data-mining perspective.

The exploration of epidemic dynamics on dynamically evolving ("adaptive") networks poses nontrivial challenges to the modeler, such as the determination of a small number of informative statistics of the detailed network state (that is, a few "good observables") that usefully summarize the overall (macroscopic, systems-level) behavior. Obtaining reduced, small size accurate models in terms of these few statistical observables--that is, trying to coarse-grain the full network epidemic model to a small but useful macroscopic one--is even more daunting. Here we describe a data-based approach to solving the first challenge: the detection of a few informative collective observables of the detailed epidemic dynamics. This is accomplished through Diffusion Maps (DMAPS), a recently developed data-mining technique. We illustrate the approach through simulations of a simple mathematical model of epidemics on a network: a model known to exhibit complex temporal dynamics. We discuss potential extensions of the approach, as well as possible shortcomings.

Single-cell genetic expression of mutant GABAA receptors causing Human genetic epilepsy alters dendritic spine and GABAergic bouton formation in a mutation-specific manner.

Mutations in genes encoding for GABAA receptor subunits is a well-established cause of genetic generalized epilepsy. GABA neurotransmission is implicated in several developmental processes including neurite outgrowth and synapse formation. Alteration in excitatory/inhibitory synaptic activities plays a critical role in epilepsy, thus here we investigated whether mutations in α1 subunit of GABAA receptor may affect dendritic spine and GABAergic bouton formation. In particular, we examined the effects of three mutations of the GABRA1 gene (D219N, A322D and K353delins18X) that were found in a cohort of French Canadian families with genetic generalized epilepsy. We used a novel single-cell genetic approach, by preparing cortical organotypic cultures from GABRA1 (flox/flox) mice and simultaneously inactivating endogenous GABRA1 and transfecting mutant α1 subunits in single glutamatergic pyramidal cells and basket GABAergic interneurons by biolistic transfection. We found that GABRA1 (-/-) GABAergic cells showed reduced innervation field, which was rescued by co-expressing α1-A322D and α1-WT but not α1-D219N. We further found that the expression of the most severe GABRA1 missense mutation (α1-A322D) induced a striking increase of spine density in pyramidal cells along with an increase in the number of mushroom-like spines. In addition, α1-A322D expression in GABAergic cells slightly increased perisomatic bouton density, whereas other mutations did not alter bouton formation. All together, these results suggest that the effects of different GABAAR mutations on GABAergic bouton and dendritic spine formation are specific to the mutation and cannot be always explained by a simple loss-of-function gene model. The use of single cell genetic manipulation in organotypic cultures may provide a better understanding of the specific and distinct neural circuit alterations caused by different GABAA receptor subunit mutations and will help define the pathophysiology of genetic generalized epilepsy syndromes.