Morphological differences in Parkinson's disease with and without rest tremor

Background : Rest tremor is a hallmark of Parkinson's disease (PD), but its pathogenesis remains incompletely understood. Nigro-striatal dopamine deficiency correlates best with bradykinesia, but not with tremor. Oscillating neurons in one or multiple localizations within the basal gangliathalamo-cortical loop may cause rest tremor, and an active contribution of the cerebellum and the cerebello-thalamo-cortical projections has been postulated. Objective : To compare the pattern of grey matter volume in PD patients with and without tremor to identify structural correlates of rest tremor. Methods : Voxel-based morphometry (VBM) of a high-resolution 3 Tesla, T1-weighted MR images, pre-processed according to an optimized protocol using SPM2, was performed in 24 patients with mild to moderate PD comparing local grey matter volume in patients with (n = 14) and without rest tremor (n = 10). Results : Grey matter volume is decreased in the right quadrangular lobe and declive of the cerebellum in PD with tremor compared to those without (PFDR < 0.05). Conclusions : These results demonstrate for the first time morphological changes in the cerebellum in PD patients with rest tremor and highlight the involvement of the cerebellum and cerebello- thalamo-cortical circuit in the pathogenesis of parkinsonian rest tremo

Perioperative Antibiotic Prophylaxis of Wound and Foreign Body Infections: Microbial Factors Affecting Efficacy

Numerous microbial factors are responsible for perioperative infections and influence the efficacy of antibiotic prophylaxis. These factors include the staphylococcal carrier state, bacterial adherence to a number of host proteins, the production of glycocalyx by sessile bacteria, and shifts in antibiotic resistance. A full understanding of the mechanisms involved will lead to further reductions in the number of postoperative infections. Unfortunately, the microbial factors affecting prophylaxis cannot be evaluated separately under clinical conditions; they are easier to study under circumstances whose bacteriologic features are well defined and in which the presence of foreign materials (e.g., sutures) greatly potentiates pathogenic mechanisms. Such circumstances exist, for example, in infections developing after "clean” surgery and in experimental models. Since even clean wounds are found to be contaminated when sampled carefully, the control of infection is more a quantitative than a qualitative problem. The critical period for the development of infection is short: an antibiotic course not exceeding 24 hours seems effective in preventing infectio

Azolylborates for Electrochemical Double Layer Capacitor Electrolytes

Asymmetric tetraalkylammonium salts of azolylborates were synthesized and studied with respect to their suitability as supporting electrolytes in electrochemical double layer capacitors. In contrast to current conducting salts used in this device, azolylborates exhibit an excellent stability towards thermal load and moisture. In addition to good conductivity and stability towards cathodic reduction we found certain limitations when more positive potentials were applie

Unchanged gastric emptying and visceral perception in early Parkinson's disease after a high caloric test meal

Delayed gastric emptying (GE) is a frequent non-motor feature in Parkinson´s disease (PD). This prospective study (clinicaltrials.gov Identifier NCT01518751) investigated GE and visceral perception in early motor phase PD patients in comparison to age-matched and younger controls. In addition, the effect of Levodopa on GE was assessed in healthy aged controls. 16 PD patients (Hoehn & Yahr 2), 11 sex-/age-matched Ctrl1 and 10 young, male Ctrl2 subjects were subjected to a high caloric (428 kcal) (13)C-Sodium Octanoate breath test strictly OFF dopaminergic medication. Visceral appetite sensation was monitored using visual analogue scales (VAS). GE was similarly studied in 7 controls ON/OFF oral Levodopa. GE was not altered in PD patients compared to age-/sex-matched and younger controls (p = 0.76). Subjective appetite perception was not altered in the PD group in comparison to Ctrl1, but was significantly higher in Ctrl2 subjects (p = 0.02). 100 mg oral Levodopa/25 mg Benserazide significantly slowed GE by 18% among healthy controls (p = 0.04). In early motor stage PD OFF dopaminergic medication, there was no GE slowing after a high caloric test meal. Levodopa, however, caused a robust GE slowing in healthy aged individuals. Our data indicate that clinically relevant GE slowing in early PD is related to the iatrogenic effect of dopamine treatment. Subjective appetite perception is not affected in this disease stage. This data add to the understanding of gastrointestinal symptoms in early motor stage PD and highlight the influence of dopaminergic medication

Levels of Free Granulocyte Elastase in Bronchial Secretions from Patients with Cystic Fibrosis: Effect of Antimicrobial Treatment Against Pseudomonas aeruginosa

Large amounts of free granulocyte elastase (GE), an enzyme capable of mediating airway damage, have been found in bronchial secretions of patients with cystic fibrosis who are infected with Pseudomonas aeruginosa. This finding indicates an imbalance between GE and its antiproteases, α1-proteinase inhibitor (α1-PI) and bronchial mucosal inhibitor (BMI), in the airways of these individuals. The effect of intravenous antimicrobial treatment against P. aeruginosa on activity and concentration of GE, BMI, and α1-PI was evaluated in 30 treatment courses of 20 patients with cystic fibrosis. Although sputum volume and level of immunoreactive GE decreased and concentrations of α1-PI and BMI increased significantly (P < .05), a high level of free GE persisted. No active α1-PI and BMI were detectable after treatment. High levels of GE correlated with a poor pulmonary condition (rs = .98, P < .001). In vitro, elastolytic activity of bronchial secretions from patients with cystic fibrosis was significantly inhibited by eglin C and an oxidation-resistant variant of α1-PI, both compounds currently produced by recombinant DNA technolog

Regularization of the circular restricted three-body problem using 'similar' coordinate systems

The regularization of a new problem, namely the three-body problem, using 'similar' coordinate system is proposed. For this purpose we use the relation of 'similarity', which has been introduced as an equivalence relation in a previous paper (see \cite{rom11}). First we write the Hamiltonian function, the equations of motion in canonical form, and then using a generating function, we obtain the transformed equations of motion. After the coordinates transformations, we introduce the fictitious time, to regularize the equations of motion. Explicit formulas are given for the regularization in the coordinate systems centered in the more massive and the less massive star of the binary system. The 'similar' polar angle's definition is introduced, in order to analyze the regularization's geometrical transformation. The effect of Levi-Civita's transformation is described in a geometrical manner. Using the resulted regularized equations, we analyze and compare these canonical equations numerically, for the Earth-Moon binary system.Comment: 24 pages, 7 figures; Accepted for publication in Astrophysics and Space Scienc

Asymptotic solution for the two-body problem with constant tangencial acceleration

An analytical solution of the two body problem perturbed by a constant tangential acceleration is derived with the aid of perturbation theory. The solution, which is valid for circular and elliptic orbits with generic eccentricity, describes the instantaneous time variation of all orbital elements. A comparison with high-accuracy numerical results shows that the analytical method can be effectively applied to multiple-revolution low-thrust orbit transfer around planets and in interplanetary space with negligible error