Brainstem Reflexes in Idiopathic Cervical Dystonia: Does Medullary Dysfunction Play a Role?

Background: Neurophysiological markers in dystonia have so far not been sistematically applied in clinical practice due to limited reproducibility of results and low correlations with clinical findings. Exceptions might be represented by the blink reflex (BR), including its recovery cycle (BRRC) and the trigemino-cervical reflex (TCR) which, compared to other neurophysiological methods, have shown more consistent alterations in cervical dystonia (CD). However, a comparison between the two techniques, and their possible correlation with disease symptoms, have not been thoroughly investigated. Objectives: To assess the role of BR, BRCC and TCR in the pathophysiology of idiopathic cervical dystonia. Methods: Fourteen patients and 14 age-matched healthy controls (HC) were recruited. Neurophysiological outcome measures included latency of R1 and R2 components of the BR, R2 amplitude, BRRC, latency and amplitude of P19/N31 complex of TCR. Clinical and demographic features of patients were also collected, including age at disease onset, disease duration, presence of tremor, sensory trick and pain. The Toronto Western Spasmodic Torticollis Rating Scale was used to characterize dystonia. Results: Compared to HC, CD patients showed increased latency of the BR R2 and decreased suppression of the BRRC. They also showed increased latency of the P19 and decreased amplitude of P19/N31 complex of TCR. The latency of P19 component of TCR was positively correlated with disease duration. Conclusions: We propose that the increased latency of R2 and P19 observed here might be reflective of brainstem dysfunction, mediated either by local interneuronal excitability changes or by subtle structural damage

The use of sensory action potential to evaluate inferior alveolar nerve damage after orthognathic surgery.

To assess and monitor the common event of neurosensory disturbance to the inferior alveolar nerve (IAN) after bilateral sagittal split osteotomy, we used clinical sensory tests and neurophysiologic test sensory action potentials. The diagnostic value of these tests was evaluated by comparing them with the degree of nerve damage reported by patients. Fourteen patients undergoing bilateral sagittal split osteotomy were analyzed preoperatively and 2 years postoperatively. Patients were evaluated bilaterally for positive and negative symptoms: light touch sensation, paraesthesia, hyperesthesia, and dysaesthesia; a "sensation score" was then calculated for each patient. Patients were also asked if they would be willing to repeat the procedure knowing the sensation loss they had now. Next, the right and left IAN were evaluated using sensory action potential and correlated with the other results. Before surgery, the medium latency difference between left and right was lower compared with postsurgery, with all patients having some deficit. The reduction in medium amplitude of 67% after the intervention was statistically significant. The frequency of abnormal findings in the electrophysiologic tests indicating IAN injury correlated with subjective sensory alteration. All patients said that they would repeat the surgery. Electrophysiologic testing is recommended for the evaluation of nerve dysfunction and seems a sensitive method for accurately assessing postsurgical nerve conduction

Polio patients in northern Italy, a 50 year follow-up

Poliomyelitis was before the immunization an important medical problem. Nowadays polio prior patients (PP) suffer from polio sequelae or have developed post-polio-syndrome (PPS) with increasing paresis, pain and fatigue

Synthesis of novel olefin complexes of palladium(0) bearing monodentate NHC, phosphine and isocyanide spectator ligands

We have synthesized and characterized seventeen new bis-NHC, mixed NHCâ\u80\u93phosphines or NHCâ\u80\u93isocyanides Pd(0) olefin complexes that can potentially act as catalysts. The complexes were characterized by standard spectroscopic methods and elemental analysis and in two cases by SC-XRD technique. We have analyzed with particular care the thermodynamic and kinetic conditions governing the one-pot synthesis of the mixed complexes. In this respect we tried to validate our results by a dedicated computational study on the mutual distribution of the isomers that could be potentially formed. However, the computational result is not clear-cut owing to the not significant value of the calculated Î\u94G0. Finally, in one case we have measured the rate of the exchange reaction between not particularly encumbered olefins

SACRAL NEUROMODULATION IN THE MANAGEMENT OF LOWER URINARY TRACT DYSFUNCTIONS: A NEUROPHYSIOLOGICAL EVALUATION

Hypothesis / aims of study Currently, sacral neuromodulation (SNM) stands as the single licensed second-line treatment for the management of intractable overactive bladder syndrome (OAB). SNM can be considered a promising, potential solution to bladder dysfunctions which have a serious impact on patients\u2019 health status and quality of life, in carefully selected patients. However several questions are still unanswered, regarding the following topic: patient selection, prognostic factors, mechanism of action, complications and revision rates, effects on central and peripheral nervous system. Neurophysiology studies could be employed to provide more evidence on SNM mechanism of action and peripheral effect. The aim of this study was to evaluate clinical and neurophysiologic characteristics of patients with lower urinary tract dysfunctions (LUTD) undergone SNM implant trying to better understand neurophysiologic modification pre- and post-implant, defining responders\u2019 pre-implant neurophysiological characteristics. Study design, materials and methods Data (demographics, medical history,urologic investigations, and diagnosis) from all patients attending our institution from February 2006 to September 2009 for a SNM implant were collected. All patients underwent a pre-implant neurophysiologic evaluation as follows: Pudendal Nerve Somatosensory Evoked Potentials (PN-SSEPs); bilateral external anal sphincter electromyography (EAS-EMG); evaluation of the bilateral pudendal-anal reflex (PAR); Electromyographic and neurographic studies of lower limbs. A post-implant neurophysiological evaluation was performed in all implant removal candidates. For comparison Student's t test was used. Results A total of 22 consecutive patients (mean age 63.1 years) attending our institution (19 women and 3 men), with refractory overactive bladder (OAB) (54.5%), non-obstructive urinary retention (UR) (27.3%), mixed urinary incontinence (9.1%); chronic pelvic pain (CPP) (9.1%) underwent a permanent SNM implant. At a mean follow-up of 3.5 months (range 2-24 months), half of the patients have their implants removed (tables I-II). Table III shows pre- and post-implant PN-SSEPs findings in patients with durable beneficial from SNM. In patients undergone implant removal, values of PN-SSEPs, EAS-EMG and PAR were normal apart one case with an increase in bilateral pudendal nerve latency. Figure I shows pre-implant EAS-EMG findings in patients having beneficial from SNM. Pre-implant EAS-EMG findings were normal in 90.9% of patient undergone implant removal. Table IV summarizes pre- and post-implant R1 and R2 latencies of PAR in patients with effective SNM implant. Interpretation of results The greater effectiveness of SNM has been observed in patients with neurological damage neurophysiologically documented. To date there are no definitive data about the exact mechanism of action of SNM although it is conceivable a modulation on the somato-sensory afferents as well as a secondary effect on both somatic (pudendal nerve) and autonomic efferent motor pathways. Concluding message Our results suggest that the neurophysiologic exploration of the pelvic floor is an important step for the identification of suitable candidates for treatment with SNM. Further well-designed trials are needed in order to better define the role of neurophysiology in SNM, not just in identifying appropriate candidates for intervention, but also to guide the surgeon in more accurate positioning of the electrodes, using intraoperative monitoring, and to change the parameters of stimulation in patients unresponsive to treatment. Table I. Characteristics of patients undergon

Olfactory swab sampling optimization for α-synuclein aggregate detection in patients with Parkinson’s disease

Background: In patients with Parkinson’s disease (PD), real-time quaking-induced conversion (RT-QuIC) detection of pathological α-synuclein (α-syn) in olfactory mucosa (OM) is not as accurate as in other α-synucleinopathies. It is unknown whether these variable results might be related to a different distribution of pathological α-syn in OM. Thus, we investigated whether nasal swab (NS) performed in areas with a different coverage by olfactory neuroepithelium, such as agger nasi (AN) and middle turbinate (MT), might affect the detection of pathological α-syn. Methods: NS was performed in 66 patients with PD and 29 non-PD between September 2018 and April 2021. In 43 patients, cerebrospinal fluid (CSF) was also obtained and all samples were analyzed by RT-QuIC for α-syn. Results: In the first round, 72 OM samples were collected by NS, from AN (NSAN) or from MT (NSMT), and 35 resulted positive for α-syn RT-QuIC, including 27/32 (84%) from AN, 5/11 (45%) from MT, and 3/29 (10%) belonging to the non-PD patients. Furthermore, 23 additional PD patients underwent NS at both AN and MT, and RT-QuIC revealed α-syn positive in 18/23 (78%) NSAN samples and in 10/23 (44%) NSMT samples. Immunocytochemistry of NS preparations showed a higher representation of olfactory neural cells in NSAN compared to NSMT. We also observed α-syn and phospho-α-syn deposits in NS from PD patients but not in controls. Finally, RT-QuIC was positive in 22/24 CSF samples from PD patients (92%) and in 1/19 non-PD. Conclusion: In PD patients, RT-QuIC sensitivity is significantly increased (from 45% to 84%) when NS is performed at AN, indicating that α-syn aggregates are preferentially detected in olfactory areas with higher concentration of olfactory neurons. Although RT-QuIC analysis of CSF showed a higher diagnostic accuracy compared to NS, due to the non-invasiveness, NS might be considered as an ancillary procedure for PD diagnosis

Interference of H-bonding and substituent effects in nitro- and hydroxy-substituted salicylaldehydes

Two intramolecular interactions, i.e., (1) hydrogen bond and (2) substituent effect, were analyzed and compared. For this purpose, the geometry of 4- and 5-X-substituted salicylaldehyde derivatives (X = NO2, H or OH) was optimized by means of B3LYP/6-311 + G(d,p) and MP2/aug-cc-pVDZ methods. The results obtained allowed us to show that substituents (NO2 or OH) in the para or meta position with respect to either OH or CHO in H-bonded systems interact more strongly than in the case of di-substituted species: 4- and 3-nitrophenol or 4- and 3-hydroxybenzaldehyde by ∼31%. The substituent effect due to the intramolecular charge transfer from the para-counter substituent (NO2) to the proton-donating group (OH) is ∼35% greater than for the interaction of para-OH with the proton-accepting group (CHO). The total energy of H-bonding for salicylaldehyde, and its derivatives, is composed of two contributions: ∼80% from the energy of H-bond formation and ∼20% from the energy associated with reorganization of the electron structure of the systems in question