The value of intraoperative neurophysiological monitoring during positioning in pediatric scoliosis correction: A case report.

Introduction: Prone position during posterior spine surgery can represent a potentially risky procedure for the nervous system. Infrequent injuries due to prone positioning consist of subtle spinal cord infarction or myelopathy that can be promptly detected by intraoperative neurophysiological monitoring (IONM), if applied in this phase of surgery. Here, we report a case that stresses the value of IONM even in detecting spinal positioning-related neurological complications during kyphoscoliosis correction. Case presentation: A 3-year-old child with a severe thoracic kyphoscoliosis with the angle in the tract T5-T6 underwent an early treatment of scoliosis with growing rods. Before instrumentation or the reduction maneuver, lower limb somatosensory and motor responses disappeared. The patient was repositioned with neck and chest in a more protective position and neuromonitoring signals returned to baseline. The surgery could be completed and the patient had no postoperative neurologic or vascular deficits. Conclusion: Our findings suggest the importance of extending neuromonitoring in the early phases of anesthesia induction and patient positioning during corrective spinal deformity surgery.

Tactile event-related potentials in amyotrophic lateral sclerosis (ALS): Implications for brain-computer interface.

OBJECTIVE: We investigated neurophysiological brain responses elicited by a tactile event-related potential paradigm in a sample of ALS patients. Underlying cognitive processes and neurophysiological signatures for brain-computer interface (BCI) are addressed. METHODS: We stimulated the palm of the hand in a group of fourteen ALS patients and a control group of ten healthy participants and recorded electroencephalographic signals in eyes-closed condition. Target and non-target brain responses were analyzed and classified offline. Classification errors served as the basis for neurophysiological brain response sub-grouping. RESULTS: A combined behavioral and quantitative neurophysiological analysis of sub-grouped data showed neither significant between-group differences, nor significant correlations between classification performance and the ALS patients' clinical state. Taking sequential effects of stimuli presentation into account, analyses revealed mean classification errors of 19.4% and 24.3% in healthy participants and ALS patients respectively. CONCLUSIONS: Neurophysiological correlates of tactile stimuli presentation are not altered by ALS. Tactile event-related potentials can be used to monitor attention level and task performance in ALS and may constitute a viable basis for future BCIs. SIGNIFICANCE: Implications for brain-computer interface implementation of the proposed method for patients in critical conditions, such as the late stage of ALS and the (completely) locked-in state, are discussed.

Modulation of affective symptoms and resting state activity by brain stimulation in a treatment-resistant case of obsessive-compulsive disorder.

The effect of transcranial direct current stimulation (tDCS) and repetitive transcranial magnetic stimulation (rTMS) on psychopathological symptoms and resting state brain activity was assessed in a patient with obsessive-compulsive disorder (OCD). tDCS and rTMS had no effect on OC symptoms. tDCS, however, improved depression and anxiety. Functional magnetic resonance imaging at baseline showed an interhemispheric asymmetry with hyperactivation of the left and hypoactivation of the right anterior neural circuits. A reduction of interhemispheric imbalance was detected after tDCS but not after rTMS. tDCS seems to be more effective than rTMS in restoring interhemispheric imbalance and improving anxiety and depression in OCD.

Why do patients change their general practitioner? Suggestions on corrective actions.

AIMS: The aim of this study was to determine what made people want to change their choice of general practitioners (GP). Furthermore, the study aimed to correlate the perceived quality of patient-GP communication with the motives inducing individuals to change their doctors. METHODS: All people requesting to change their GPs were asked by the office staff to complete a questionnaire. RESULTS: The study identifies the following main reasons for changing GP: patients perceived the doctor as unwilling to listen to them; patients did not receive the services that they considered useful for their health; and patients perceived the doctor's disorganization as an obstacle to accessibility. CONCLUSIONS: These findings suggest several actions to improve the doctor-patient relationship, including training for physicians to develop their communication skills; involving public health operators in helping to understand the rights and obligations of patients and doctors; and a reorganization of the GP's workload.

Event-related brain potential modulation in patients with severe brain damage.

OBJECTIVE: The limited evidence and inconsistency of purposeful behaviors in patients in a minimally conscious state (MCS) asks for objective electrophysiological marker of the level of consciousness. Here, a comparison between event-related potentials (ERPs) was investigated using different level of stimulus complexity. METHODS: The patients in vegetative state were 11 and the MCS patients were 6 [corrected]. Three oddball paradigms with different level of complexity were applied: sine tones, the subject's own name versus sine tones and other first names. Latencies and amplitudes of N1 and P3 waves were compared. RESULTS: Cortical responses were found in all MCS patients, and in 6 of 11 patients in VS. Healthy controls and MCS patients showed a progressive increase of P3 latency in relation to the level of stimulus complexity. No modulation of P3 latency was observed in the vegetative patients. CONCLUSIONS: These results suggest that the modulation of P3 latency related to stimulus complexity may represent an objective index of higher-order processing integration that predicts the recovery of consciousness from VS to MCS when clinical manifestations are inconsistent. SIGNIFICANCE: Modulation of P3 latency related to stimulus complexity could provide valuable information about the cognitive capabilities of unresponsive patients.

Development of a reconstruction procedure for the halo current distribution.

In magnetic-confinement toroidal machines, only a limited number of first wall modules can be equipped with current sensors, giving partial information about the distribution of the "halo" current (HC) injected into the vessel when the plasma hits the wall during disruptions. The knowledge of the complete distribution of the HC is necessary for evaluating the J x B loads exerted on the vessel structure. Since the pattern of contact areas of plasma with the wall during disruptions is spatially discontinuous, the HCs injected in the first wall (FW) cannot be efficiently fitted using harmonic functions. A procedure has been developed and implemented for estimating all the currents injected in vessel on the basis of a limited number of current sensors on the FW modules. The results obtained in the case of a numerical machine model with simplified geometry indicate that the procedure can be successfully applied to machines with more complex HC distribution, such as ITER.

Active-feedback control of the magnetic boundary for magnetohydrodynamic stabilization of a fusion plasma.

Stable operation with control on magnetohydrodynamic modes has been obtained in the modified reversed field experiment employing a set of 192 feedback controlled saddle coils. Improvements of plasma temperature, confinement (twofold), and pulse length (threefold) and, as a consequence of the magnetic fluctuation reduction, strong mitigation of plasma-wall interaction and mode locking are reported.

Feedback stabilization of multiple resistive wall modes.

Active feedback stabilization of multiple independent resistive wall modes is experimentally demonstrated in a reversed-field pinch plasma. A reproducible simultaneous suppression of several nonresonant resistive wall modes is achieved. Coupling of different modes due to the limited number of the feedback coils is observed in agreement with theory. The feedback stabilization of nonresonant RWMs also has an effect on tearing modes that are resonant in the central plasma, leading to a significant prolongation of the discharge pulse.

Cell cycle perturbations and cytogenetic damage induced by low energy protons in human primary fibroblasts.

Endpoints related to cell cycle perturbations were investigated in human primary fibroblasts irradiated with 1-4 Gy of either protons (7.7 and 28.5 keV.micron-1) or X rays. Regardless of the quality of radiation, 8 h after irradiation cells accumulated in the G2 phase, but such accumulation was maintained at 24 h from treatment only in 28.5 keV.micron-1 protons. A marked G1/S-transition block was observed in proton as well as in X ray-treated cultures up to 24 h, with doses as low as 1 Gy. On the other hand, the number of cells positive to p21 antibody reaction was higher after proton than after X ray treatment, indicating that the 'complexity' of lesions may play a critical role in the induction of p21.

Relative biological effectiveness of light ions in human tumoural cell lines: role of protein p53.

Protons and alpha particles of high linear energy transfer (LET) have shown an increased relative biological effectiveness (RBE) with respect to X/gamma rays for several cellular and molecular endpoints in different in vitro cell systems. To contribute to understanding the biochemical mechanisms involved in the increased effectiveness of high LET radiation, an extensive study has been designed. The present work reports the preliminary result of this study on two human tumoural cell lines, DLD1 and HCT116, (with different p53 status), which indicate that for these cell lines, p53 does not appear to take a part in the response to radiation induced DNA damage, suggesting an alternative p53-independent pathway and a cell biochemical mechanism dependent on the cell type.

Dissecting the immune response to moloney murine sarcoma/leukemia virus-induced tumors by means of a DNA vaccination approach.

The intramuscular inoculation of Moloney murine sarcoma/leukemia (M-MSV/M-MuLV) retroviral complex gives rise to sarcomas that undergo spontaneous regression due to the induction of a strong immune reaction mediated primarily by cytotoxic T lymphocytes (CTL). We used a DNA-based vaccination approach to dissect the CTL response against the Gag and Env proteins of M-MSV/M-MuLV in C57BL/6 (B6) mice and to evaluate whether plasmid DNA-immunized mice would be protected against a subsequent challenge with syngeneic tumor cells expressing the viral antigens. Intramuscular DNA vaccination induced CTL against both Gag and Env proteins. A detailed analysis of epitopes recognized by CTL generated in mice inoculated with the whole virus and with the Gag-expressing plasmid confirmed the presence of an immunodominant peptide in the leader sequence of Gag protein (Gag85-93, CCLCLTVFL) that is identical to that described in B6 mice immunized with Friend MuLV-induced leukemia cells. Moreover, CTL generated by immunization with the Env-encoding plasmid recognized a subdominant Env peptide (Env189-196, SSWDFITV), originally described in the B6.CH-2(bm13) mutant strain. B6 mice immunized with the Gag-expressing plasmid were fully protected against a lethal tumor challenge with M-MuLV-transformed MBL-2 leukemia cells, while vaccination with the Env-expressing plasmid resulted in rejection of the tumor in 44% of the mice and in increased survival of an additional 17% of the animals. Taken together, these results indicate the existence of a hierarchy in the capacity of different structural viral proteins to induce a protective immune response against retrovirus-induced tumors.

Diagnostic factors in pediatric primary headache.

Primary headaches are frequent in children. They are difficult to diagnose because there is much disagreement about the interpretation of the historical data and the use of signs and/or symptoms in diagnosis. It would be useful, therefore, to standardize this procedure. We used linear discriminant analysis to determine a classification rule capable of diagnosing new cases of chronic and recurrent primary headache in children. We considered 23 symptoms in 118 patients. Through discriminant analysis we chose five variables: frequency of the attacks, type of pain, neurologic deficits, nausea, and vomiting. With this classification rule, we obtained a total correct classification of 84.7% for migraine, psychogenic headache, and non-defined headache in respect to the diagnoses formulated by a pediatrician and a child neuropsychiatrist after 3 months of follow-up. Our method for diagnosing migraine has a sensitivity of 95% and a specificity of 100%. The algorithm, validated on another 105 pediatric patients, produced a total correct result of 82.9%.