Motor and Sensory Features of Cervical Dystonia Subtypes: Data From the Italian Dystonia Registry.

Introduction: Cervical dystonia (CD) is one of the most common forms of adult-onset isolated dystonia. Recently, CD has been classified according to the site of onset and spread, in different clinical subgroups, that may represent different clinical entities or pathophysiologic subtypes. In order to support this hypothesis, in this study we have evaluated whether different subgroups of CD, that clinically differ for site of onset and spread, also imply different sensorimotor features. Methods: Clinical and demographic data from 842 patients with CD from the Italian Dystonia Registry were examined. Motor features (head tremor and tremor elsewhere) and sensory features (sensory trick and neck pain) were investigated. We analyzed possible associations between motor and sensory features in CD subgroups [focal neck onset, no spread (FNO-NS); focal neck onset, segmental spread (FNO-SS); focal onset elsewhere with segmental spread to neck (FOE-SS); segmental neck involvement without spread (SNI)]. Results: In FNO-NS, FOE-SS, and SNI subgroups, head tremor was associated with the presence of tremor elsewhere. Sensory trick was associated with pain in patients with FNO-NS and with head tremor in patients with FNO-SS. Conclusion: The frequent association between head tremor and tremor elsewhere may suggest a common pathophysiological mechanism. Two mechanisms may be hypothesized for sensory trick: a gating mechanism attempting to reduce pain and a sensorimotor mechanism attempting to control tremor.

Spatial and egocentric mental rotation in patients with cervical dystonia.

Mental rotation has attracted the interest of cognitive research on dystonia, but at the moment, contrasting data are available on whether this complex cognitive ability is impaired in the disorder. Here, we assessed spatial and egocentric mental rotation in patients with cervical dystonia (CD). Patients with CD and healthy controls were required to perform a letter rotation task (spatial mental rotation) and to judge laterality of front-facing and back-facing human images (egocentric mental rotation). CD patients were selectively impaired on letter rotation, whereas they did not differ from controls when judging laterality of both front-facing and back-facing bodies. These findings support the view according to which neural circuits involved in spatial processing are dysfunctional in CD.

The effects of mechanical focal vibration on walking impairment in multiple sclerosis patients: A randomized, double-blinded vs placebo study.

BACKGROUND: Multiple Sclerosis is a heterogeneous disorders involving in early stage gait and balance. Together with immunomodulating therapies, rehabilitation had a crucial role in improving motor tasks and quality of life. Between the emerging techniques, Focal Vibrations (FV) could play a role, but they have been used in MS only to reduce muscle tone and fatigue alone or together with botulinum toxin. OBJECTIVE: To assess whether FV is effective on walking impairment in a cohort of MS patients. METHODS: We performed a single-centre randomized, double-blind, sham-controlled study to investigate efficacy of FV vs sham vibration in 20 RR MS patients. Ten patients received treatment with the active device and ten patients sham treatment. Demographical, clinical and gait instrumental data analysis have been collected for each patient at baseline (T0), after treatment (T1) and after three weeks of wash out (T2). RESULTS: Both groups were clinically and demographically comparable. Treated patients showed significant improvements during the first right step (FRS) (p = 0.007), average stride lenght (ASL) (p = 0.012), double support right (DSRT) (p = 0.016) and left (DSLT) (p = 0.003) time. Non-treated patients didn't show any significance for any dynamic variables. Moreover, on posturographic measurements we registered only a trend towards significance in swing area with eyes open (SAEO) (p = 0.087). We also found in treated group significant improvements in FRT (p = 0.018); BBS (p = 0.037) and FSS scales (p = 0.038) between T1 and T0. Lastly, we found a significant inverse correlation in the treated group between disease duration and percentage of improvement for DSLT (r = - 0.775; p = 0.014) in T1 vs T0 and percentage of improvement of FSS, with an inverse correlation with both disease duration (r = - 0.775; p = 0.014) and AGE (r = - 0.733, p = 0.025) in T1 vs T0CONCLUSION: Our results suggest a beneficial effect of FV on walking impairment in MS patients suffering from spasticity and/or postural instability, which partially lasted until follow up.

Distribution pattern and activity of mitochondria during oocyte growth and maturation in the ascidian Styela plicata.

The process of oocyte maturation is underlined by a redistribution of cellular organelles, among which mitochondria play a functional role for the acquisition of fertilization and developmental competence. In this paper, we applied electron and confocal microscopy by using DIOC6 and JC-1 stain to evaluate mitochondria distribution pattern and activity during different stages of oocyte growth in the ascidian Styela plicata. Three categories of oocytes at the germinal vesicle stage underlying the vitellogenic process were characterized on the basis of size, pigmentation and accessory cells. Mitochondria were spread throughout the cytoplasm at the smallest oocyte stage and gradually migrated to the periphery of the subcortical cytoplasm at the intermediate stage. At the fully grown oocyte stage, mitochondria were aggregated in the subcortical cytoplasm. This pattern of polarized mitochondria distribution correlates significantly with an increase in mitochondria potential and activity. In this paper we discuss the relationship of mitochondria to the acquisition of oocyte developmental competence.

Ion currents modulating oocyte maturation in animals.

Growing oocytes are arrested at the first prophase of meiosis which is morphologically identified by the presence of a large and vesicular nucleus, called the germinal vesicle. The dissolution of the germinal vesicle marks the resumption of meiosis during which the oocyte undergoes massive modifications up to the second meiotic block, which is removed at fertilization. The interval between the first and the second meiotic block is defined as maturation and the events occurring during this period are crucial for ovulation, fertilization, and embryo development. Oocytes are excitable cells that react to stimuli by modifying their electrical properties as a consequence of ion currents flowing through ion channels on the plasma membrane. These electrical changes have been largely described at fertilization whereas little information is available during oocyte maturation. The aim of this review is to give an overview on the involvement of ion channels and ion currents during oocyte maturation in species from invertebrates to mammals. The results summarized here point to the possible functional role of ion channels underlying oocyte growth and maturation.

[Ca2+]i rise at in vitro maturation in bovine cumulus-oocyte complexes.

An intracellular calcium ([Ca(2+)]i) rise has been described in cumulus-oocyte complexes (COCs) following luteinizing hormone (LH) exposure. Together with cAMP, Ca(2+) is a candidate signal for resumption of meiosis. Here, we analyzed if the most common hormones involved in oocyte maturation can induce the same Ca(2+) signal. In addition, we characterized the source of this signal. Immature, in vitro-matured, and roscovitine-meiotically arrested COCs were loaded with Fluo-4 AM, stimulated with hormones/growth factors, and tested for [Ca(2+)](i) variations in cumulus cells. Reagents known to inhibit or stimulate [Ca(2+)](i) rises were used to characterize these [Ca(2+)](i) dynamics. Finally, expression of LH receptors (LHRs) in COCs was analyzed by immunofluorescence. In immature COCs, follicle-stimulating hormone (FSH) elicited a single [Ca(2+)](i) rise that was higher than those induced by LH and growth hormone (GH), whereas epithelial growth factor failed to induce any changes in [Ca(2+)](i). The [Ca(2+)](i) rise induced by FSH was higher in immature COCs; was reduced in roscovitine-arrested, immature COCs; and was negligible in gonadotropin-induced, in vitro-matured COCs. In the case of spontaneous- and GH-matured COCs, however, FSH stimulation caused a lower [Ca(2+)](i) rise. The hormone-induced [Ca(2+)](i) rise was due to: (i) external Ca(2+) entry; (ii) intercellular communication; and (iii) intracellular Ca(2+) stores. Immunofluorescence revealed that LHRs were expressed throughout the cumulus cells. The above results show that: (i) gonadotropins and GH cause a [Ca(2+)](i) rise in cumulus cells; (ii) this [Ca(2+)](i) rise results from extra-, inter-, and intra-cellular cumulative Ca(2+) fluxes; and (iii) LHRs are distributed on either outer or inner cumulus cells.

Ion currents involved in oocyte maturation, fertilization and early developmental stages of the ascidian Ciona intestinalis.

Electrophysiological techniques were used to study the role of ion currents in the ascidian Ciona intestinalis oocyte plasma membrane during different stages of growth, meiosis, fertilization and early development. Three stages of immature oocytes were discriminated in the ovary, with the germinal vesicle showing specific different features of growth and maturation. Stage-A (pre-vitellogenic) oocytes exhibited the highest L-type calcium current activity and were incompetent for meiosis resumption. Stage-B (vitellogenic) oocytes showed a progressive disappearance of calcium currents and the first appearance of sodium currents that remained high during the maturation process, up to the post-vitellogenic stage-C oocytes. The latter had acquired meiotic competence, undergoing spontaneous in vitro maturation and interacting with the spermatozoon. However, fertilized oocytes did not produce normal larvae, suggesting that cytoplasmic maturation may affect embryo development. In mature oocytes at the metaphase I stage, sodium currents were present and remained high up to the zygote stage. Oocytes fertilized in the absence of sodium showed significant reduction of the fertilization current amplitude and high development of anomalous "rosette" embryos. Current amplitudes became negligible in embryos at the 2- and 4-cell stage, whereas resumption of all the current activities occurred at the 8-cell embryo. Taken together, these results suggest: (i) an involvement of L-type calcium currents in initial oocyte meiotic progression and growth; (ii) a role of sodium currents at fertilization; (iii) a role of the fertilization current in ensuring normal embryo development.

Role of cyclic AMP in the maturation of Ciona intestinalis oocytes.

Immature oocytes are arrested at prophase I of the meiotic process and maturation onset is indicated by oocyte nuclear disassembly (germinal vesicle breakdown or GVBD). Signaling pathways that elevate intracellular cyclic AMP (cAMP) may either prevent or induce oocyte maturation depending on the species. In some marine invertebrates and, in particular, in ascidian oocytes, cAMP triggers GVBD rather than blocking it. In this paper, we tested different cAMP elevators in fully grown oocytes at the germinal vesicle stage (GV) of the ascidian Ciona intestinalis. We demonstrated that through the activation of adenylate cyclase or the inhibition and phosphodiesterases the oocyte remained at the GV stage. This effect was reversible as the GV-arrested oocytes, rinsed and incubated in sea water, are able to undergo spontaneous maturation and extrusion of follicle cells. In addition, oocytes acquire the ability to be fertilized and start early development. However, morphology of follicle cells, embryos and larvae from in vitro matured oocytes showed different morphology from those derived from in vivo mature oocytes. The role and the transduction mechanism of cAMP in the regulation of oocyte maturation were discussed. Finally, we indicated a variation of biological mechanisms present in the ascidian species; moreover, we sustain evidence proving that tunicates share some biological mechanisms with vertebrates. This information provided new hints on the importance of ascidians in the evolution of chordates.

Impact of marine drugs on cytoskeleton-mediated reproductive events.

Marine organisms represent an important source of novel bioactive compounds, often showing unique modes of action. Such drugs may be useful tools to study complex processes such as reproduction; which is characterized by many crucial steps that start at gamete maturation and activation and virtually end at the first developmental stages. During these processes cytoskeletal elements such as microfilaments and microtubules play a key-role. In this review we describe: (i) the involvement of such structures in both cellular and in vitro processes; (ii) the toxins that target the cytoskeletal elements and dynamics; (iii) the main steps of reproduction and the marine drugs that interfere with these cytoskeleton-mediated processes. We show that marine drugs, acting on microfilaments and microtubules, exert a wide range of impacts on reproductive events including sperm maturation and motility, oocyte maturation, fertilization, and early embryo development.

Ion current activity and molecules modulating maturation and growth stages of ascidian (Ciona intestinalis) oocytes.

Electrophysiological techniques were used to study ion currents in the ascidian Ciona intestinalis oocyte plasma membranes during different stages of growth and meiosis. Three stages (A, B, C) of immature oocytes were discriminated in the ovary, with the germinal vesicle (GV) showing specific different features of growth and maturation. Stage A (pre-vitellogenic) oocytes exhibited the highest L-type Ca(2+)current activity, and were incompetent for meiosis resumption. Stage B (vitellogenic) oocytes showed Na(+) currents that remained high during the maturation, up to the post-vitellogenic stage C oocytes. The latter had acquired meiotic competence, undergoing spontaneous maturation and interacting with the spermatozoon. However, fertilized oocytes did not produce normal larvae, suggesting that cytoplasmic maturation plays a specific role in embryo development. Spontaneous maturation was inhibited at low pH whereas trypsin was able to trigger germinal vesicle breakdown (GVBD) regardless of pH; in addition spontaneous maturation was not affected by removal of follicle cells or by inhibiting junctional communication between oocyte and follicle cells. Taken together these results imply: (i) Ca(2+) and Na(+) currents are involved in meiotic progression, growth, and acquisition of meiotic competence; (ii) trypsin-like molecules may have a role as candidates for providing the physiological stimulus to resume meiosis. Finally, we provide evidence that follicle cells in Ciona are not involved in triggering GVBD as it occurs in other ascidians.

Impact of marine drugs on animal reproductive processes.

The discovery and description of bioactive substances from natural sources has been a research topic for the last 50 years. In this respect, marine animals have been used to extract many new compounds exerting different actions. Reproduction is a complex process whose main steps are the production and maturation of gametes, their activation, the fertilisation and the beginning of development. In the literature it has been shown that many substances extracted from marine organisms may have profound influence on the reproductive behaviour, function and reproductive strategies and survival of species. However, despite the central importance of reproduction and thus the maintenance of species, there are still few studies on how reproductive mechanisms are impacted by marine bioactive drugs. At present, studies in either marine and terrestrial animals have been particularly important in identifying what specific fine reproductive mechanisms are affected by marine-derived substances. In this review we describe the main steps of the biology of reproduction and the impact of substances from marine environment and organisms on the reproductive processes.

5-HT-receptive structures are localized in the interblastomere cleft of Paracentrotus lividus early embryos.

Local application of the agonists of serotonin receptors of third type 5-HTQ, SR57277A and quipazine into the interblastomere cleft of the sea urchin Paracentrotus lividus embryo during first cleavage division, evokes specific membrane currents, whereas application of these drugs out of contact area show currents of lower amplitude and longer latent period. At the same time 5-HT3-receptor agonist quipazine imitates interblastomere signal in half embryos, but corresponding antagonists prevent it. Present data develop the hypothesis of protosynapse, demonstrating that the distribution of membrane serotonin receptors is limited to the period of cleavage division and localized in the interblastomere contact area. A possible role of spatial-temporal restriction of receptors at the interblastomere contact area is discussed in relation to the subsequent embryo development.

Regulatory roles of nitric oxide during larval development and metamorphosis in Ciona intestinalis.

Metamorphosis in the ascidian Ciona intestinalis is a very complex process which converts a swimming tadpole to an adult. The process involves reorganisation of the body plan and a remarkable regression of the tail, which is controlled by caspase-dependent apoptosis. However, the endogenous signals triggering apoptosis and metamorphosis are little explored. Herein, we report evidence that nitric oxide (NO) regulates tail regression in a dose-dependent manner, acting on caspase-dependent apoptosis. An increase or decrease of NO levels resulted in a delay or acceleration of tail resorption, without affecting subsequent juvenile development. A similar hastening effect was induced by suppression of cGMP-dependent NO signalling. Inhibition of NO production resulted in an increase in caspase-3-like activity with respect to untreated larvae. Detection of endogenously activated caspase-3 and NO revealed the existence of a spatial correlation between the diminution of the NO signal and caspase-3 activation during the last phases of tail regression. Real-time PCR during development, from early larva to early juveniles, showed that during all stages examined, NO synthase (NOS) is always more expressed than arginase and it reaches the maximum value at late larva, the stage immediately preceding tail resorption. The spatial expression pattern of NOS is very dynamic, moving rapidly along the body in very few hours, from the anterior part of the trunk to central nervous system (CNS), tail and new forming juvenile digestive organs. NO detection revealed free diffusion from the production sites to other cellular districts. Overall, the results of this study provide a new important link between NO signalling and apoptosis during metamorphosis in C. intestinalis and hint at novel roles for the NO signalling system in other developmental and metamorphosis-related events preceding and following tail resorption.

Ca2+ and Na+ current patterns during oocyte maturation, fertilization, and early developmental stages of Ciona intestinalis.

Using the whole-cell voltage clamp technique, the electrical changes in oocyte and embryo plasma membrane were followed during different meiotic and developmental stages in Ciona intestinalis. We show, for the first time, an electrophysiological characterization of the plasma membrane in oocytes at the germinal vesicle (GV) stage with high L-type calcium (Ca2+) current activity that decreased through meiosis. Moreover, the absence of Ca2+ reduced germinal vesicle breakdown (GVBD), which is consistent with a role of Ca2+ currents in the prophase/metaphase transition. In mature oocytes at the metaphase I (MI) stage, Ca2+ currents decreased and then disappeared and sodium (Na+) currents first appeared remaining high up to the zygote stage. Intracellular Ca2+ release was higher in MI than in GV, indicating that Ca2+ currents in GV may contribute to fill the stores which are essential for oocyte contraction at fertilization. The fertilization current generated in Na+ free sea water was significantly lower than the control; furthermore, oocytes fertilized in the absence of Na+ showed high development of anomalous "rosette" embryos. Current amplitudes became negligible in embryos at the 2- and 4-cell stage, suggesting that signaling pathways that mediate first cleavage do not rely on ion current activities. At the 8-cell stage embryo, a resumption of Na+ current activity and conductance occurred, without a correlation with specific blastomeres. Taken together, these results imply: (i) an involvement of L-type Ca2+ currents in meiotic progression from the GV to MI stage; (ii) a role of Na+ currents during electrical events at fertilization and subsequent development; (iii) a major role of plasma membrane permeability and a minor function of specific currents during initial cell line segregation events.