Peripheral Nervous System Abnormalities Research Articles

Cardiac sympathetic denervation and anxiety in Parkinson disease

BackgroundAnxiety in Parkinson disease (PD) negatively impacts quality of life. While research predominantly focuses on central nervous system changes, some evidence suggests a connection between peripheral autonomic dysfunctions and PD-related anxiety. The role of the peripheral autonomic nervous system in this context may be overlooked. ObjectivesThis study explores the link between anxiety symptoms and cardiac sympathetic denervation in PD using 11C-meta-hydroxyephedrine ([11C]HED) PET cardiac imaging. MethodsWe studied 34 non-demented PD subjects, assessing anxiety levels through the Spielberg Anxiety State-Trait test trait section (STAI-T). Patients underwent comprehensive assessments along with [11C]HED cardiac and [11C]DTBZ brain PET. To identify subdimensions of STAI-T, we employed principal components analysis (PCA). We examined associations between the anxiety subdimensions and two measures of cardiac sympathetic denervation from [11C]HED PET. We utilized correlation and linear regression models for these analyses. ResultsPCA revealed two STAI-T results components: anxiety-depressive and pure anxiety subcomponents. Only pure anxiety significantly correlated with measures of cardiac sympathetic denervation (rhos −0.40, p = 0.018; 0.35, p = 0.043). Regression models confirmed a significant association, with cardiac sympathetic denervation explaining ∼20 % of pure anxiety variance, independent of sex, dopaminergic impairment, and anxiolytic treatments. DiscussionThis study provides preliminary evidence of peripheral autonomic nervous system abnormalities contributing to PD-related anxiety, suggesting dysregulation in peripheral autonomic functions influencing anxiety perception.

Joubert syndrome presenting bilateral peroneal neuropathies: A case report.

Joubert syndrome (JS) is a rare genetic disorder that presents with various neurological symptoms, primarily involving central nervous system dysfunction. Considering the etiology of JS, peripheral nervous system abnormalities cannot be excluded; however, cases of JS accompanied by peripheral nervous system abnormalities have not yet been reported. Distinct radiological findings on brain magnetic resonance imaging were considered essential for the diagnosis of JS. However, recently, cases of JS with normal or nearly normal brain morphology have been reported. To date, there is no consensus on the most appropriate diagnostic method for JS when imaging-based diagnostic approach is challenging. This report describes the case of an adult patient who exhibited bilateral peroneal neuropathies and was finally diagnosed with JS through genetic testing. A 27-year-old man visited our outpatient clinic due to a gait disturbance that started at a very young age. The patient exhibited difficulty maintaining balance, especially when walking slowly. Oculomotor apraxia was observed on ophthalmic evaluation. During diagnostic workups, including brain imaging and direct DNA sequencing, no conclusive findings were detected. Only nerve conduction studies revealed profound bilateral peroneal neuropathies. We performed whole genome sequencing to obtain a proper diagnosis and identify the gene mutation responsible for JS. This case represents the first instance of peripheral nerve dysfunction in JS. Further research is needed to explore the association between JS and peripheral nervous system abnormalities. Detailed genetic testing may serve as a valuable tool for diagnosing JS when no prominent abnormalities are detected in brain imaging studies.

Abstract 20: Axonal Neuropathy and Inflammatory Response in Peripheral Nerves of a Murine Cerebral Amyloid Angiopathy Model

Introduction: Cerebral amyloid angiopathy (CAA) induces intracerebral hemorrhages, small vessel disease, and cognitive decline in elderly individuals. CAA is also associated with slower walking speed and abnormal gait rhythms compared to healthy controls. Little is known regarding the impact of peripheral nervous system abnormalities on CAA-associated gait disturbance. Furthermore, it is unknown whether peripheral nerves pose extracerebral targets of amyloid-related endoneurial inflammation. Hypothesis: Gait disturbance in a CAA model is associated with peripheral neuropathy through endoneurial inflammation related to amyloid accumulation. Methods: Aged (19-24 months) Tg-SwDI mice (CAA mice) of both sexes harboring mutations of human amyloid precursor protein (APP) were used as a CAA model. Age-matched C57BL/6 wild-type (WT) mice were used as controls (n=6-11/grp). Gait disturbance and sensorimotor function were assessed via DigiGait and grip strength testing. Flow cytometry was used to analyze immune cells in the sciatic nerve. Tibial nerve morphometry was performed to assess for neuropathy. Results: CAA mice had weaker grip strength ( CAA: 97.7 ± 17.6 g, WT 111.5 ± 8.1 g, p=0.039 ) and evidence of neuropathic gait disturbances, reflected by increased paw angles ( CAA: 21.1 ± 4.8°, WT 11.7 ± 3.4°, p=0.0002 ) and reduced paw areas ( CAA: 0.4 ± 0.05 cm 2 , WT 0.5 ± 0.06 cm 2 , p=0.013 ) impacting the ground when walking compared to WT mice. Tibial nerve morphometry showed a reduced number of myelinated nerve fibers ( CAA: 1023 ± 230.1, WT 1318 ± 45.8, p=0.0047 ) suggesting potential axonal degeneration in CAA mice. Flow cytometry showed an increase in the count of macrophage (both M1 and M2 subtypes) lineage cells ( M1 CAA: 102.3 ± 29.2, WT 57.9 ± 36.3, p=0.009 ) as well as M1 macrophage associated pro-inflammatory cytokine TNF-α ( CAA: 99.7 ± 28.3, WT 53.8 ± 12.2, p=0.009 ) in sciatic nerves of CAA mice compared to WT mice. Conclusions: CAA mice display an enhanced inflammatory response within the endoneurium which may contribute to observed axonal degeneration, ultimately impairing sensorimotor function and gait. Further studies are needed to unravel the mechanistic interplay between amyloid pathology, endoneurial inflammation, and axonal neuropathy in this CAA model.

Imbalance and gait impairment in Parkinson's disease: discussing postural instability and ataxia.

Gait and balance difficulties pose significant clinical challenges in Parkinson's disease (PD). The impairment of physiological mechanisms responsible for maintaining natural orthostatism plays a central role in the pathophysiology of postural instability observed in PD. In addition to the well-known rigidity and abnormalities in muscles and joints, various brain regions involved in the regulation of posture, balance, and gait, such as the basal ganglia, cerebellum, and brainstem regions like the pontine peduncle nucleus, are affected in individuals with PD. The recognition of the cerebellum's role in PD has been increasingly acknowledged. Cortical areas and their connections are associated with freezing of gait, a type of frontal lobe ataxia commonly observed in PD. Furthermore, impairments in the peripheral nervous system, including those caused by levodopatherapy, can contribute to gait impairment and imbalance in PD patients. Consequently, individuals with PD may exhibit frontal ataxia, sensory ataxia, and even cerebellar ataxia as underlying causes of gait disturbances and imbalance, starting from the early stages of the disease. The complex interplay between dysfunctional brain regions, impaired cortical connections, and peripheral nervous system abnormalities contributes to the multifaceted nature of gait and balance difficulties in PD. Understanding the intricate mechanisms is crucial for the development of effective therapeutic approaches targeting these specific deficits in PD.

Overlapping neurological phenotypes in two extended consanguineous families with novel variants in the CNTNAP1 and ADGRG1 genes.

Population diversity is important and rare disease isolates can frequently reveal novel homozygous or biallelic mutations that lead to expanded clinical heterogeneity, with diverse clinical presentations. The present study describes two consanguineous families with a total of seven affected individuals suffering from a clinically similar severe syndromic neurological disorder, with abnormal development and central nervous system (CNS) and peripheral nervous system (PNS) abnormalities. Whole exome sequencing (WES) and Sanger sequencing followed by 3D protein modeling was performed to identify the disease-causing gene. RNA was extracted from the fresh blood of both families affected and healthy individuals. The families were clinically assessed in the field in different regions of Khyber Pakhtunkhwa. Magnetic resonance imagining was obtained in the probands and blood was collected for DNA extraction and WES was performed. Sanger sequencing confirmed a homozygous, likely pathogenic mutation (GRCh38: chr17:42684199G>C; (NM_003632.3): c.333G>C);(NP_003623.1): p.(Trp111Cys) in the CNTNAP1 gene in family A, previously associated with Congenital Hypo myelinating Neuropathy 3 (CHN3; OMIM # 618186) and a novel nonsense variant in family B, (GRCh38: chr16: 57654086C>T; NC_000016.10 (NM_001370440.1): c.721C>T); (NP_001357369.1): p.(Gln241Ter) in the ADGRG1 gene previously associated with bilateral frontoparietal polymicrogyria (OMIM # 606854); both families have extended CNS and PNS clinical manifestations. In addition, 3D protein modeling was performed for the missense variant, p.(Trp111Cys), identified in the CNTNAP1, suggesting extensive secondary structure changes that might lead to improper function or downstream signaling. No RNA expression was observed in both families affected and healthy individuals hence showing that these genes are not expressed in blood. In the present study, two novel biallelic variants in the CNTNAP1 and ADGRG1 genes in two different consanguineous families with a clinical overlap in the phenotype were identified. Thus, the clinical and mutation spectrum is expanded to provide further evidence that CNTNAP1 and ADGRG1 are very important for widespread neurological development.

Excess Dietary Vitamin B-6 Alters Startle Behavior of Rats

Excessive intakes of vitamin B-6 can produce peripheral nervous system abnormalities, but few reports of central nervous system effects exist. We measured startle response, a central nervous system reflex, in rats fed excess pyridoxine to determine if subtle effects on central nervous system function could be detected. Female Long-Evans rats (218 g; n = 12) were fed either 1, 10, 100, 200 or 300 times the requirement of pyridoxine HCl (7 mg/kg) for 7 wk. Startle behavior was assessed weekly in chambers that allowed quantification of movement in response to stimuli. Food intake and body weights did not differ among groups (P > 0.1), and urinary vitamin B-6 excretion reflected intake (P < 0.001). Overt toxicity was not observed. There was a marginally significant effect of pyridoxine intake over time (P = 0.053) on the amplitude of response to a startling acoustic stimulus (117 dB, 40 ms) administered alone; the response appeared attenuated at the three highest pyridoxine concentrations. When the same stimulus was preceded by either a 70- or 75-dB prepulse (40 ms), responses of groups fed the two highest pyridoxine concentrations were significantly reduced relative to those fed the two lowest concentrations (P < 0.05). No effect of diet was seen with a startling tactile stimulus. Changes in central nervous system function were detected in rats fed excess vitamin B-6 using techniques of startle behavior measurement.

Cardiorenal Syndrome: The Role of Neural Connections Between the Heart and the Kidneys.

The maintenance of cardiovascular homeostasis is highly dependent on tightly controlled interactions between the heart and the kidneys. Therefore, it is not surprising that a dysfunction in one organ affects the other. This interlinking relationship is aptly demonstrated in the cardiorenal syndrome. The characteristics of the cardiorenal syndrome state include alterations in neurohumoral drive, autonomic reflexes, and fluid balance. The evidence suggests that several factors contribute to these alterations. These may include peripheral and central nervous system abnormalities. However, accumulating evidence from animals with experimental models of congestive heart failure and renal dysfunction as well as humans with the cardiorenal syndrome suggests that alterations in neural pathways, from and to the kidneys and the heart, including the central nervous system are involved in regulating sympathetic outflow and may be critically important in the alterations in neurohumoral drive, autonomic reflexes, and fluid balance commonly observed in the cardiorenal syndrome. This review focuses on studies implicating neural pathways, particularly the afferent and efferent signals from the heart and the kidneys integrating at the level of the paraventricular nucleus in the hypothalamus to alter neurohumoral drive, autonomic pathways, and fluid balance. Further, it explores the potential mechanisms of action for the known beneficial use of various medications or potential novel therapeutic manipulations for the treatment of the cardiorenal syndrome. A comprehensive understanding of these mechanisms will enhance our ability to treat cardiorenal conditions and their cardiovascular complications more efficaciously and thoroughly.

Fluoroquinolone use in a rural practice.

Fluoroquinolones (FQs) are a commonly prescribed class of antibiotics in Canada. Evidence of a constellation of possible adverse events is developing. Central and peripheral nervous system abnormalities and collagen-related events (including aortic aneurysm/dissection, tendinopathy/rupture and retinal detachment) are associated with FQ exposure in large population-based aftermarket studies. In 2017, Health Canada warned about rare FQ-related persistent or disabling side effects. This study explores FQ use in a rural community. Antibiotic prescriptions (including FQs) in the over 18 adult population (5416) were measured in the town of Sioux Lookout for 5 years, January 2013 to 31 December 2017. FQ prescriptions accounted for 16.0% of adult antibiotics, superseded by penicillins (21.1%) and macrolides (18.2%). Ciprofloxacin accounted for one half of FQ use (51.2%), followed by levofloxacin (36.7%) and norfloxacin (13.3%). FQs were commonly used for respiratory (33%) and urinary tract infections (18%). Aftermarket evidence reports increased risk of 'disabling and persistent serious adverse events'(Health Canada) in patients using FQs. Appropriate clinical caution should be exercised in the prescribing of FQs. Common overuse seems to occur in the treatment of uncomplicated community-acquired pneumonia and cystitis, despite recommendations to use other antimicrobial agents as first-line treatments.

Choroid Plexus Enlargement and Allostatic Load in Schizophrenia.

Although schizophrenia is a brain disorder, increasing evidence suggests that there may be body-wide involvement in this illness. However, direct evidence of brain structures involved in the presumed peripheral-central interaction in schizophrenia is still unclear. Seventy-nine previously treatment-naïve first-episode schizophrenia patients who were within 2-week antipsychotics initial stabilization, and 41 age- and sex-matched healthy controls were enrolled in the study. Group differences in subcortical brain regional structures measured by MRI and the subclinical cardiovascular, metabolic, immune, and neuroendocrine biomarkers as indexed by allostatic load, and their associations were explored. Compared with controls, patients with schizophrenia had significantly higher allostatic load (P = .001). Lateral ventricle (P < .001), choroid plexus (P < .001), and thalamus volumes (P < .001) were significantly larger, whereas amygdala volume (P = .001) was significantly smaller in patients. The choroid plexus alone was significantly correlated with higher allostatic load after age, sex, education level, and the total intracranial volume were taken into account (t = 3.60, P < .001). Allostatic load was also significantly correlated with PANSS positive (r = 0.28, P = .016) and negative (r = -0.31, P = .008) symptoms, but in opposite directions. The peripheral multisystemic and central nervous system abnormalities in schizophrenia may interact through the choroid plexus during the early stage of the illness. The choroid plexus might provide a sensitive structural biomarker to study the treatment and prevention of brain-periphery interaction abnormalities in schizophrenia.

Cukurova University experience of lysosomal diseases in adulthood: Report of 57 patients

Metachromatic leukodystrophy (a deficiency of arylsulfatase A [ARSA]) is a fatal demyelinating lysosomal disease with no approved treatment. We aimed to assess the long-term outcomes in a cohort of patients with early-onset metachromatic leukodystrophy who underwent haemopoietic stem-cell gene therapy (HSC-GT).This is an ad-hoc analysis of data from an ongoing, non-randomised, open-label, single-arm phase 1/2 trial, in which we enrolled patients with a molecular and biochemical diagnosis of metachromatic leukodystrophy (presymptomatic late-infantile or early-juvenile disease or early-symptomatic early-juvenile disease) at the Paediatric Clinical Research Unit, Ospedale San Raffaele, in Milan. Trial participants received HSC-GT, which consisted of the infusion of autologous HSCs transduced with a lentiviral vector encoding ARSA cDNA, after exposure-targeted busulfan conditioning. The primary endpoints of the trial are safety (toxicity, absence of engraftment failure or delayed haematological reconstitution, and safety of lentiviral vector-tranduced cell infusion) and efficacy (improvement in Gross Motor Function Measure [GMFM] score relative to untreated historical controls, and ARSA activity, 24 months post-treatment) of HSC-GT. For this ad-hoc analysis, we assessed safety and efficacy outcomes in all patients who had received treatment and been followed up for at least 18 months post-treatment on June 1, 2015. This trial is registered with ClinicalTrials.gov, number NCT01560182.Between April, 2010, and February, 2013, we had enrolled nine children with a diagnosis of early-onset disease (six had late-infantile disease, two had early-juvenile disease, and one had early-onset disease that could not be definitively classified). At the time of analysis all children had survived, with a median follow-up of 36 months (range 18–54). The most commonly reported adverse events were cytopenia (reported in all patients) and mucositis of different grades of severity (in five of nine patients [grade 3 in four of five patients]). No serious adverse events related to the medicinal product were reported. Stable, sustained engraftment of gene-corrected HSCs was observed (a median of 60·4% [range 14·0–95·6] lentiviral vector-positive colony-forming cells across follow-up) and the engraftment level was stable during follow-up; engraftment determinants included the duration of absolute neutropenia and the vector copy number of the medicinal product. A progressive reconstitution of ARSA activity in circulating haemopoietic cells and in the cerebrospinal fluid was documented in all patients in association with a reduction of the storage material in peripheral nerve samples in six of seven patients. Eight patients, seven of whom received treatment when presymptomatic, had prevention of disease onset or halted disease progression as per clinical and instrumental assessment, compared with historical untreated control patients with early-onset disease. GMFM scores for six patients up to the last follow-up showed that gross motor performance was similar to that of normally developing children. The extent of benefit appeared to be influenced by the interval between HSC-GT and the expected time of disease onset. Treatment resulted in protection from CNS demyelination in eight patients and, in at least three patients, amelioration of peripheral nervous system abnormalities, with signs of remyelination at both sites.Our ad-hoc findings provide preliminary evidence of safety and therapeutic benefit of HSC-GT in patients with early-onset metachromatic leukodystrophy who received treatment in the presymptomatic or very early-symptomatic stage. The results of this trial will be reported when all 20 patients have achieved 3 years of follow-up.Italian Telethon Foundation and GlaxoSmithKline.

Prader-Willi Syndrome: an under-recognized cause of hypotonia?

The “floppy infant” is a well-recognized entity characterized by general­ized hypotonia presenting at birth or in early life. Hypotonia represents a diagnostic challenge because it may be the presentation sign of numerous diseases, as central or peripheral nervous system abnormalities, myopathies, genetic disorders, endocrinopathies, metabolic diseases and acute/chronic illness. Prader-Willi syndrome (PWS) is a complex neurodevelopmental disorder that results from an abnormality in chromosome 15. Diagnosis is often delayed because clinical findings are relatively nonspecific and the dysmorphism is often subtle. We describe three term male newborns admitted in the first day of life for hypotonia and feeding difficulties. Pregnancy and familiar history were unremarkable. Clinical examination revealed marked global hypotonia, few active movements, weak cry, poor suck reflex, micrognathia, cryptorchidism, facial dysmorphic features: almond-shaped eyes with short palpebral fissures, narrow bifrontal diameter and short neck. Laboratory evaluations were normal. Brain ultrasound and magnetic resonance had no alterations. Cardiac and metabolic evaluations were irrelevant. PWS was suspected and genetic evaluation was performed. The methylation analysis specific for PWS confirmed the diagnosis. In the three cases it was observed development milestones delay, with progressive improvement after multidisciplinary approach. At last follow-up visit, all of them walk alone, explore the surrounding environment, understand simple language and say some words. These reports reinforce the idea that PWS should be considered in the presence of newborn hypotonia, and feeding difficulties, even in absence of typical facial features. Detecting PWS at neonatal age is important because it allows early intervention and better management of such infants.

Lentiviral haemopoietic stem-cell gene therapy in early-onset metachromatic leukodystrophy: an ad-hoc analysis of a non-randomised, open-label, phase 1/2 trial

Metachromatic leukodystrophy (a deficiency of arylsulfatase A [ARSA]) is a fatal demyelinating lysosomal disease with no approved treatment. We aimed to assess the long-term outcomes in a cohort of patients with early-onset metachromatic leukodystrophy who underwent haemopoietic stem-cell gene therapy (HSC-GT). This is an ad-hoc analysis of data from an ongoing, non-randomised, open-label, single-arm phase 1/2 trial, in which we enrolled patients with a molecular and biochemical diagnosis of metachromatic leukodystrophy (presymptomatic late-infantile or early-juvenile disease or early-symptomatic early-juvenile disease) at the Paediatric Clinical Research Unit, Ospedale San Raffaele, in Milan. Trial participants received HSC-GT, which consisted of the infusion of autologous HSCs transduced with a lentiviral vector encoding ARSA cDNA, after exposure-targeted busulfan conditioning. The primary endpoints of the trial are safety (toxicity, absence of engraftment failure or delayed haematological reconstitution, and safety of lentiviral vector-tranduced cell infusion) and efficacy (improvement in Gross Motor Function Measure [GMFM] score relative to untreated historical controls, and ARSA activity, 24 months post-treatment) of HSC-GT. For this ad-hoc analysis, we assessed safety and efficacy outcomes in all patients who had received treatment and been followed up for at least 18 months post-treatment on June 1, 2015. This trial is registered with ClinicalTrials.gov, number NCT01560182. Between April, 2010, and February, 2013, we had enrolled nine children with a diagnosis of early-onset disease (six had late-infantile disease, two had early-juvenile disease, and one had early-onset disease that could not be definitively classified). At the time of analysis all children had survived, with a median follow-up of 36 months (range 18-54). The most commonly reported adverse events were cytopenia (reported in all patients) and mucositis of different grades of severity (in five of nine patients [grade 3 in four of five patients]). No serious adverse events related to the medicinal product were reported. Stable, sustained engraftment of gene-corrected HSCs was observed (a median of 60·4% [range 14·0-95·6] lentiviral vector-positive colony-forming cells across follow-up) and the engraftment level was stable during follow-up; engraftment determinants included the duration of absolute neutropenia and the vector copy number of the medicinal product. A progressive reconstitution of ARSA activity in circulating haemopoietic cells and in the cerebrospinal fluid was documented in all patients in association with a reduction of the storage material in peripheral nerve samples in six of seven patients. Eight patients, seven of whom received treatment when presymptomatic, had prevention of disease onset or halted disease progression as per clinical and instrumental assessment, compared with historical untreated control patients with early-onset disease. GMFM scores for six patients up to the last follow-up showed that gross motor performance was similar to that of normally developing children. The extent of benefit appeared to be influenced by the interval between HSC-GT and the expected time of disease onset. Treatment resulted in protection from CNS demyelination in eight patients and, in at least three patients, amelioration of peripheral nervous system abnormalities, with signs of remyelination at both sites. Our ad-hoc findings provide preliminary evidence of safety and therapeutic benefit of HSC-GT in patients with early-onset metachromatic leukodystrophy who received treatment in the presymptomatic or very early-symptomatic stage. The results of this trial will be reported when all 20 patients have achieved 3 years of follow-up. Italian Telethon Foundation and GlaxoSmithKline.

Presence of Decreased Intraepidermal Nerve Fiber Density Consistent with Small Fiber Neuropathy in Patients with Central Post-Stroke Pain

Dear Editor, In the United States, approximately 800,000 strokes occur annually, with 11%-55% of stroke survivors experiencing post-stroke pain [1–5]. Central post-stroke pain (CPSP) is recognized as a neuropathic condition often defined as being of thalamic origin, although extra-thalamic stroke can also result in CPSP [3,5–7]. The reported prevalence of CPSP is between 1% and 12% following all stroke, and up to 18% when sensory deficits are present [3,6,7]. Although the pathophysiology of CPSP remains incompletely understood, as the name implies, CPSP is most often associated with “central,” not peripheral nervous system abnormalities. Here we report four consecutive patients without prior evidence of a peripheral neuropathy, who developed CPSP following a stroke and in who further evaluation led to the documentation of skin biopsy findings consistent with small fiber neuropathy (SFN). Decreased peripheral intraepidermal nerve fiber density (IENF) is observed in many painful conditions associated with SFN including complex regional pain syndrome, diabetic neuropathy, chemotherapy-induced neuropathy, and hypothyroidism [8–15]. Similar skin biopsy findings have been recently reported in some, but not all, fibromyalgia patients leading some clinicians to consider the diagnosis of SFN in certain fibromyalgia patients. Although the precise role that the loss of small caliber (presumptive nociceptor) IENF plays in clinical pain symptoms is still unclear, their normal physiologic role in acute pain mechanisms is well-defined. Since the anatomy of the nociceptive/pain pathways (matrix) approximates a closed-loop system, coupled with the recognition that …

Early insights into the neurobiology of pain in sickle cell disease: A systematic review of the literature.

Novel insights into the neurobiology of sickle cell disease (SCD) pain have recently been discovered. We systematically reviewed the literature focusing on original research that examined the biology of pain in SCD and/or addressed assessment or treatment of neuropathic pain in SCD. This review of 15 articles that met inclusion criteria provides epidemiological, basic, and clinical data that support central and/or peripheral nervous system abnormalities likely contribute to sickle cell pain. Continued basic and clinical investigation into pain neurobiology is imperative to translate these discoveries into novel ways to assess and treat neuropathic pain and decrease patient suffering.

Electrophysiological characterization of adult-onset Niemann–Pick type C disease

In infantile and juvenile Niemann–Pick type C (NPC) disease electrophysiological studies have shown central (CNS) and peripheral (PNS) nervous system abnormalities. However, an extensive electrophysiological evaluation of CNS and PNS in adult form of NPC is still lacking. The aim of the study is to assess in adult-onset NPC disease the involvement of CNS and PNS by a multimodal electrophysiological approach. Three patients affected by adult form of NPC disease underwent electrophysiological evaluation including nerve conduction study (NCS), magnetic motor (MEPs), visual (VEPs), somatosensory (SSEPs) and brainstem auditory (BAEPs) evoked potentials. NCS, MEPs, VEPs and upper limb SSEPs were normal. Lower limb SSEPs were abnormal in all patients and abnormalities were consistent with a length-dependent process affecting the central somatosensory pathway. BAEPs were abnormal in all patients with both peripheral and central impairment of auditory pathway. Our electrophysiological findings suggest that auditory and lower limb somatosensory pathways are constantly affected in adult-onset form of NPC disease. The involvement of PNS, pyramidal, visual and upper limb somatosensory pathways might occur later during the course of disease.

53. Electrophysiological characterization in adult form Niemann-Pick type C disease

In infantile and juvenile NPC disease electrophysiological studies have shown central (CNS) and peripheral (PNS) nervous system abnormalities. However, an extensive electrophysiological evaluation of CNS and PNS in adult form of NPC is still lacking. To assess in Niemann-Pick type C disease (NPC) the involvement of the central (CNS) and peripheral (PNS) nervous system by a multimodal electrophysiological approach. Three patients affected by adult form of NPC underwent electrophysiological evaluation including nerve conduction study (NCS), motor (MEPs) and somatosensory (SEPs) evoked potentials at upper and lower limbs, visual (VEPs) and brainstem auditory (BAEPs) evoked potentials. NCS, VEPs, MEPs and upper limb SEPs were normal. Lower limb SEPs were abnormal in all patients and abnormalities were consistent with a central somatosensory pathway involvement (CCT: 21.2 ± 0.6 ms). BAEPs were constantly abnormal with peripheral and central type lesions. Our electrophysiological findings are in keeping with pathological evidence of dysfunction at brainstem level between acoustic nerve and inferior colliculus/superior olivary nucleus for auditory pathways and at gracile nuclei for somatosensory pathways. Moreover, our results, unlike cases of infantile and juvenile NPC disease, suggest the sparing of PNS and of visual and corticospinal pathways.

Organ-specific function of adhesion G protein-coupled receptor GPR126 is domain-dependent

Despite their abundance and multiple functions in a variety of organ systems, the function and signaling mechanisms of adhesion G protein-coupled receptors (GPCRs) are poorly understood. Adhesion GPCRs possess large N termini containing various functional domains. In addition, many of them are autoproteolytically cleaved at their GPS sites into an N-terminal fragment (NTF) and C-terminal fragment. Here we demonstrate that Gpr126 is expressed in the endocardium during early mouse heart development. Gpr126 knockout in mice and knockdown in zebrafish caused hypotrabeculation and affected mitochondrial function. Ectopic expression of Gpr126-NTF that lacks the GPS motif (NTF(ΔGPS)) in zebrafish rescued the trabeculation but not the previously described myelination phenotype in the peripheral nervous system. These data support a model in which the NTF of Gpr126, in contrast to the C-terminal fragment, plays an important role in heart development. Collectively, our analysis provides a unique example of the versatile function and signaling properties of adhesion GPCRs in vertebrates.

CFTR-deficient pigs display peripheral nervous system defects at birth

Peripheral nervous system abnormalities, including neuropathy, have been reported in people with cystic fibrosis. These abnormalities have largely been attributed to secondary manifestations of the disease. We tested the hypothesis that disruption of the cystic fibrosis transmembrane conductance regulator (CFTR) gene directly influences nervous system function by studying newborn CFTR(-/-) pigs. We discovered CFTR expression and activity in Schwann cells, and loss of CFTR caused ultrastructural myelin sheath abnormalities similar to those in known neuropathies. Consistent with neuropathic changes, we found increased transcripts for myelin protein zero, a gene that, when mutated, can cause axonal and/or demyelinating neuropathy. In addition, axon density was reduced and conduction velocities of the trigeminal and sciatic nerves were decreased. Moreover, in vivo auditory brainstem evoked potentials revealed delayed conduction of the vestibulocochlear nerve. Our data suggest that loss of CFTR directly alters Schwann cell function and that some nervous system defects in people with cystic fibrosis are likely primary.

Objective Biomarkers or Symptom Scores for the Classification of Fibromyalgia Syndrome?

Multiple abnormalities in pain processing have been reported in patients with chronic musculoskeletal pain syndromes including fibromyalgia (FM). These changes include mechanical and thermal hyperalgesia, decreased thresholds to mechanical and thermal stimuli (allodynia) as well as central sensitization, all of which are fundamental to the generation of clinical pain. In addition to pain, self-reported symptoms like negative mood, non-refreshing sleep, and dyscognition, are common in FM. The pathogenesis of FM is only partially understood, but peripheral tissue changes and nervous system abnormalities have been implicated. These tissue abnormalities include decreased blood flow, increased levels of muscle metabolites, and degenerative joint changes. Indirect evidence from interventions that decrease tonic peripheral impulse input in patients with FM suggest that their overall pain and hyperalgesia is dependent on signaling from deep tissues. At least some of this peripheral impulse input seems to undergo abnormal pain processing in the central nervous system including increased pain facilitation as well as inadequate pain inhibition. Thus interventions that either decrease peripheral input and/or improve central pain processing abnormalities appear to be promising strategies for FM patients. The 1990 FM classification criteria were instrumental for research that greatly improved our current understanding of FM mechanisms. These criteria required widespread pain and mechanical hyperalgesia at ≥ 11 out of 18 body sites (tender points). In 2010 new FM criteria were introduced which only require self-reported somatic and cognitive symptoms, use complex scoring algorithms, and lack any objective mechanistic assessments. This lack of objective biomarker, however, may limit the usefulness of the new FM Criteria for research and clinical practice. Overall the diagnosis as well as the treatment of FM may benefit from improved classification criteria which should include relevant disease biomarkers that are fundamental for the development and persistence of FM and other chronic musculoskeletal pain syndromes, like abnormal central nervous system processing abnormalities of nociceptive signals. Keywords: Biomarker, central sensitization, nociception, fibromyalgia, chronic pain

Analysis of diagnostic criteria in adamantiades-behçet disease: A retrospective study

Adamantiades-Behçet's disease (ABD) is a chronic-relapsing, inflammatory and multi-systemic disease. Any organ or system may be involved: ABD presents a great variety of cutaneous and mucosal lesions, ocular manifestations, central and peripheral nervous system abnormalities, joint as well as gastrointestinal involvement. Since clear pathognomonic clinical features and laboratory tests are lacking, the diagnosis of ABD mainly relies on the characteristic clinical features. Several sets of diagnostic criteria have been used. The International Study Group for Behçet Disease (ISGBD) in 1990 formulated a set of criteria to warrant uniformity of both diagnosis and classification. Therefore, in 2006, a new set was proposed by the International Team for the Revision of the International Criteria for Behçet's Disease (ITR-ICBD) not only to uniform the previous criteria but also to establish best accuracy, along with an optimum sensivity and specificity. The aims of this study are both to analyze the clinical features of ABD patients and to validate the ISGBD and ITR-ICDB criteria for the diagnosis of ABD in our cohort.