Electrophysiological Predictors of Clinical Outcome in Traumatic Neuropathies: A Multicenter Prospective Study.

Objectives. This prospective, observational, multicentre study aims to identify electrodiagnostic (EDX) markers of clinical recovery in patients with traumatic neuropathy (TN) receiving surgical (S) and nonsurgical (NS) treatments. Methods. Subjects referred to the Italian Traumatic Neuropathy Network between 2010 and 2011 (307 patients, for a total of 444 TN) were evaluated with serial clinical/EDX evaluations at 6, 12, 24, and 36 months of follow-up. Results. Primary surgery was performed in 21 subjects with open lesions and evidence of neurotmesis, while closed lesions were treated with either conservative medical approach (216 patients) or secondary surgery (70 patients), according to the clinical spontaneous recovery at 4-6 months. Clinical improvement correlated with the increase of the compound muscle action potential amplitude (OR 3.76; CI 1.61-8.76), particularly in the S group (OR 7.25; CI 1.2-43.87), and with sensory nerve action potential amplitude in the NS group (OR 4.35; CI 1.14-16.69). No correlations were found with needle electromyography qualitative evaluations, changes in maximal voluntary recruitment, age, and gender. Conclusions. Nerve conduction studies (NCS) represent the more accurate neurophysiological markers of clinical outcome in patients with TN. Significance. Serial NCS assessments predict the functional recovery in TN, increasing the accuracy of peripheral nerves surgical decision-making process.

A comprehensive characterization of mitochondrial DNA mutations in glioblastoma multiforme.

Glioblastoma multiforme (GBM) is the most malignant brain cancer in adults, with a poor prognosis, whose molecular stratification still represents a challenge in pathology and clinics. On the other hand, mitochondrial DNA (mtDNA) mutations have been found in most tumors as modifiers of the bioenergetics state, albeit in GBM a characterization of the mtDNA status is lacking to date. Here, a characterization of the burden of mtDNA mutations in GBM samples was performed. First, investigation of tumor-specific vs. non tumor-specific mutations was carried out with the MToolBox bioinformatics pipeline by analyzing 45 matched tumor/blood samples, from whole genome or whole exome sequencing datasets obtained from The Cancer Genome Atlas (TCGA) consortium. Additionally, the entire mtDNA sequence was obtained in a dataset of 104 fresh-frozen GBM samples. Mitochondrial mutations with potential pathogenic interest were prioritized based on heteroplasmic fraction, nucleotide variability, and in silico prediction of pathogenicity. A preliminary biochemical analysis of the activity of mitochondrial respiratory complexes was also performed on fresh-frozen GBM samples. Although a high number of mutations was detected, we report that the large majority of them does not pass the prioritization filters. Therefore, a relatively limited burden of pathogenic mutations is indeed carried by GBM, which did not appear to determine a general impairment of the respiratory chain. This article is part of a Directed Issue entitled: Energy Metabolism Disorders and Therapies.

Unraveling the contribution of ectoenzymes to myeloma life and survival in the bone marrow niche.

The bone marrow provides a protected environment for generating a vast array of cell types. Bones are thus a dynamic source of structural components and soluble factors used either locally or at a distance from their site of production. We discuss the role of ectoenzymes in the bone niche where human myeloma grows. Selected ectoenzymes have been tested for their ability to promote production of substrates involved in signaling, synthesis of growth factors and hormones, and modulation of the immune response. Because of the difficulty of simultaneously tracking all these activities, we narrow our focus to events potentially influencing synthesis of adenosine (ADO), an important regulator of multiple biological functions, including local immunological tolerance. Our working hypothesis, to be discussed and partially tested herein, is that CD38, and likely BST1/CD157--both NAD(+) -consuming enzymes, are active in the myeloma niche and lead a discontinuous chain of ectoenzymes whose final products are exploited by the neoplastic plasma cell as part of its local survival strategy. Coadjuvant ectoenzymes include PC-1/CD203a, CD39, and CD73, which control the production of ADO. Results discussed here and from ongoing experiments indicate that the myeloma niche hosts the canonical, as well as alternative, pathways of ADO generation. Other possibilities are presented and discussed.

Teleconsulting for minor head injury: the Piedmont experience.

We evaluated the benefits of teleconsulting for patients hospitalised with minor head injuries in centres without neurosurgery. In the Piedmont region, 1462 consultation requests were received at specialist centres in 2009, relating to 519 patients with a minor head injury diagnosis (ICD 850-854). These were compared with the details of 1895 patients admitted with the same diagnosis during 2009, but for whom no consultations were requested. The mortality risk in the two groups was estimated using logistic regression, after adjusting for the principal confounding factors (sex, age, seriousness of the patient's injury at diagnosis, referral centre). The estimated risk of death for patients for whom no consultation was requested was an odds ratio of 1.32 (95% CI 1.08 to 1.74) compared to those who received a teleconsultation. However, after adjusting for the confounding factors, the risk was not significant (odds ratio = 1.25, 95% CI 0.83 to 1.91). A stratified analysis identified a significant effect for elderly people, aged over 70 years, in whom the odds ratio was 1.14 (95% CI 1.04 to 1.82). The results confirm the benefits of telemedicine, in particular for elderly patients, when teleconsultation is requested in the case of minor head injury.

Relevance of intraoperative D wave in spine and spinal cord surgeries.

PURPOSE: The combined recordings of epidural-(D wave) and muscle motor evoked potentials (m-MEPs) have been proposed in many studies in intramedullary spinal cord tumour (IMSCT) surgery, although not all agree. Furthermore, the usefulness of the intraoperative monitoring of motor systems using these methods in other types of spine surgery has not yet been clearly confirmed. The aim of this study is to test the impact of intraoperative D wave on the monitorability and motor outcome in spine surgery. METHODS: Intraoperative recording of posterior tibial nerve somatosensory potentials, lower limb m-MEPs (LLm-MEPs) and epidurally recorded D wave caudally to the surgical level was attempted in a total of 103 spine and spinal cord surgeries (23 IMSCT, 55 extramedullary spinal cord tumours and 25 myelopathies). RESULTS: There was a 97.1 %, overall monitorability where at least 1 of the 3 modalities was applicable in 100 surgical procedures. Baseline LLm-MEPs were recorded bilaterally in 85 cases and unilaterally in 11. A caudal D wave was recorded in 97 cases. Transient, or persistent intraoperative modifications occurred in 14/23 IMSCT, 5/55 extramedullary spinal cord tumours and in 2/25 myelopathies. The presence of a persistent stable caudal D wave was predictive of a good motor outcome even when the LL-MEPs were absent and/or when lost during surgery. CONCLUSIONS: Not only is intraoperative D wave recording to be considered mandatory in IMSCT surgery but it should also be attempted in other types of spine/spinal cord surgeries.

Different aquaporin-4 expression in glioblastoma multiforme patients with and without seizures.

Aquaporin-4 (AQP-4), the most important water channel in the brain, is expressed by astrocyte end feet abutting microvessels. Altered expression levels of AQP-4 and redistribution of the protein throughout the membranes of cells found in glioblastoma multiforme (GBM) lead to development of the edema often found surrounding the tumor mass. Dysregulation of AQP-4 also occurs in hippocampal sclerosis and cortical dysplasia in patients with refractory partial epilepsy. This work reports on analysis of the relationship between AQP-4 expression and the incidence of epileptic seizures in patients with GBM. Immunohistochemical and polymerase chain reaction techniques were used to evaluate AQP-4 in biopsy specimens from 19 patients with GBM, 10 of who had a history of seizures before surgery. AQP-4 mRNA levels were identical in the two groups of patients, but AQP-4 expression was more frequently detected on the GBM membranes from specimens of patients with seizures than from individuals without (10 versus 2, P < 0.001). We conclude that reduced expression of cell surface AQP-4 is characteristic of GBM patients without seizures, likely attributable to a posttranslational mechanism.

Neuropathic pain in post-burn hypertrophic scars: a psychophysical and neurophysiological study.

INTRODUCTION: Pain complicates hypertrophic post-burn pathologic scars (PPS) METHODS: To investigate the possible neuropathic origin of pain, 13 patients with painful PPS involving at least 1 hand underwent clinical examination, including the Douleur Neuropathique en 4 questions (DN4) questionnaire; median, ulnar, and radial nerve conduction studies (NCS); cold- (CDT) and heat-induced pain threshold evaluation by quantitative sensory testing; and cutaneous silent period (CSP) testing of the abductor pollicis brevis. Controls included 9 patients with non-painful PPS, 52 healthy subjects, and 28 patients with carpal tunnel syndrome (CTS). RESULTS: All patients with painful PPS had possible neuropathic pain (DN4 score ≥4). NCS signs of CTS were similarly present in PPS subjects with or without pain. Hands with painful PPS had lower CDT and CSP duration, more frequent cold- and heat-pain hypesthesia, and more thermal allodynia than controls. CONCLUSIONS: In PPS, possible neuropathic pain is associated with psychophysical and neurophysiological abnormalities suggestive of small-fiber damage.

Chiari and Syringomyelia Consortium: a model of multidisciplinary and sharing path for rare diseases.

Piemonte and Valle d'Aosta Interregional Network for Rare Diseases (RD) is a model of "diffuse" network; it involves all the health system specialists devoted to the diagnosis, the therapy and the follow-up of a RD. The Consortium is a multidisciplinary team operating throughout the Region composed of volunteer Physicians and Biologists that promotes periodical meetings to develop shared protocols. In 2008 the Specialist-Technical Committee for the Interregional RD Network approved the set up of the "Chiari and Syringomyelia Consortium" (CSC) with two specific objectives: to identify the shared diagnostic criteria and to develop the interdisciplinary diagnostic-therapeutic-assistance path (DTAP) to be used interregionally. Other objectives are: to define the prevalence of the pathologies (both symptomatic and asymptomatic, both in adults and children) and to improve collaboration between the patient Associations and the Physicians.

Traumatic peripheral nerve injuries: epidemiological findings, neuropathic pain and quality of life in 158 patients.

The objectives of this study were (1) epidemiological analysis of traumatic peripheral nerve injuries; (2) assessment of neuropathic pain and quality of life in patients affected by traumatic neuropathies. All consecutive patients with a diagnosis of traumatic neuropathies from four Italian centres were enrolled. Electromyography confirmed clinical level and site diagnosis of peripheral nerve injury. All patients were evaluated by disability scales, pain screening tools, and quality of life tests. 158 consecutive patients for a total of 211 traumatic neuropathies were analysed. The brachial plexus was a frequent site of traumatic injury (36%) and the radial, ulnar, and peroneal were the most commonly involved nerves with 15% of iatrogenic injuries. Seventy-two percent of the traumatic neuropathies were painful. Pain was present in 66% and neuropathic pain in 50% of all patients. Patients had worse quality of life scores than did the healthy Italian population. Moreover, there was a strong correlation between the quality of life and the severity of the pain, particularly neuropathic pain (Short Form-36 [SF-36] p < 0.005; Beck Depression Inventory [BDI] p < 0.0001). Traumatic neuropathies were more frequent in young males after road accidents, mainly in the upper limbs. Severe neuropathic pain and not only disability contributed to worsening the quality of life in patients with traumatic neuropathies.

Glioblastoma cancer stem cells: heterogeneity, microenvironment and related therapeutic strategies.

Glioblastoma Multiforme (GBM) is an incurable malignancy. GBM patients have a short life expectancy despite aggressive therapeutic approaches based on surgical resection followed by adjuvant radiotherapy and concomitant chemotherapy. Glioblastoma growth is characterized by a high motility of tumour cells, their resistance to both chemo/radio-therapy, apoptosis inhibition leading to failure of conventional therapy. Cancer Stem Cells (CSCs), identified in GBM as well as in many other cancer types, express the membrane antigen prominin-1 (namely CD133). These cells and normal Neural Stem Cells (NSC) share surface markers and properties, i.e. are able to self-renew and differentiate into multiple cell types. Stem cell self-renewal depends on microenvironmental cues, including Extracellular Matrix (ECM) composition and cell types. Therefore, the role of microenvironment needs to be evaluated to clarify its importance in tumour initiation and progression through CSCs. The specific microenvironment of CSCs was found to mimic in part the vascular niche of normal stem cells. The targeting of GMB CSCs may represent a powerful treatment approach. Lastly, in GBM patients cancer-initiating cells contribute to the profound immune suppression that in turn correlated with CSCs STAT3 (CD133 + ). Further studies of microenvironment are needed to better understand the origin of GMB/GBM CSCs and its immunosuppressive properties.