Nerve excitability properties in early preclinical diabetic neuropathy

Diabetic polyneuropathy can be easily diagnosed when the nerve conduction studies are affected. Strength Duration Time (SDTc) reflects nerve excitability properties and was previously used several times to demonstrate the excitability properties of the nerves in the existence of electrophysiologically developed diabetic polyneuropathy. But as we all know, diabetic patients may experience neuropathic symptoms even though their routine nerve conduction studies are normal. SDTc may be useful in this early stages of developing neuropathy. In this study we aimed to evaluate the SDTc properties of diabetic patients in this early preclinic stage. Recently SDTc was commonly studied in the upper extremities but most of the diabetic neuropathies are predominant in the lower extremities. So here we also studied both upper and lower extremities to demonstrate a possible difference. © 2011 Elsevier Ireland Ltd

Capsula interna-related restless leg syndrome: A case report

Restless Legs Syndrome (RLS) may be primary or secondary. As a secondary etiological factor, stroke has been rarely reported in the literature. Here, we present the case of a patient with infarctions in the internal capsule who experienced RLS symptoms. A 48-year-old female was admitted with right hemiparesis and right central facial paralysis. Her cranial MRI revealed lacunar infarcts in the crus posterior of the left internal capsule and in crus anterior of the right internal capsule. One month later, she described uncomfortable and odd sensations affecting both legs. Her symptoms emerged at nights, additionally, movement of the legs provided temporary relief. She was diagnosed with RLS and started on Pramipexole 0.5 mg/day. Her symptoms resolved completely with this treatment. Because her RLS symptoms appeared in the first month of the disease and her neuroimaging results showed a correlation between possible anatomical localization and the symptoms, the current case has been accepted as poststroke RLS. © Archives of Neuropsychiatry, published by Galenos Publishing

Testing of the excitability of a peripheral nerve in migraine patients

Disorders in the functioning of ion channels, especially of Na+ channels, are at present suggested to play a role in the pathogenesis of migraine. Thus, migraine can be considered a channelopathy. The following question, however, remains open: Are such disorders related exclusively to the brain or also to the peripheral nervous system? In our study, we compared the excitability characteristics of the n. medianus in migraine patients and control-group subjects and also tried to find possible differences between subgroups of the patients suffering from migraine with or without aura. For this purpose, we measured the strength-duration time constant and rheobase using stimulation of the above nerve and EMG recording from the m. abductor pollicis brevis. We found no statistically significant differences in the indices of excitability of the peripheral nerve between the groups of control subjects and migraine patients and also between the above-mentioned subgroups of patients. © 2012 Springer Science+Business Media, Inc

Effect of alpha-lipoic acid on small fibre neuropathy findings in patients with type 2 diabetes mellitus

Objective: Cutaneous silent period (CSP) is an inhibitory spinal reflex and the afferent arm of this response involves A-delta nerve fibers. The aim of this study was to investigate CSP parameters in patients with type 2 diabetes mellitus (T2DM) and to examine the effects of alpha-lipoic acid (ALA) treatment on CSP. To the best of our knowledge, this investigation has not yet been carried out until date. Methods: Seventeen patients with T2DM and 23 healthy volunteers were studied. CSP latency and duration in the upper and lower extremities of both the groups were examined. In T2DM patients, the variables were examined before and after ALA treatment. Results: CSP latency in T2DM patients was longer than that in the controls. In the patient group, CSP latency in the upper and lower extremities and CSP Latency Differences (LD) shortened in the third month after treatment compared with the pre-treatment values. Conclusions: The results suggest that ALA treatment may alleviate small-fiber neuropathy in T2DM patients and that CSP may be a useful supportive tool to evaluate ALA treatment effectiveness. © 2015, Ege University Press. All rights reserved

Contributions of biogeographical functions to species accumulation may change over time in refugial regions

Aim: Elevated biodiversity is the result of the cradle, museum or sink functions. The contributions of these three functions to species accumulation and their changes through time remain unknown for glacial refugia. Additionally, our understanding of the role these functions played during pre-glacial periods is limited. We test for changes in contributions of functions through time leading to the current diversity patterns using a model refugium and taxon. Location: Anatolia, Western Palaearctic. Taxon: Freshwater neritid snails (genus Theodoxus). Methods: Assessments were made to define molecular operational taxonomic units (MOTUs) for Theodoxus and reaffirm the genus as a suitable model taxon with elevated interspecific diversity in noted glacial refugia. Thereafter, we constructed a time-calibrated multilocus Bayesian phylogeny of mtDNA and nDNA by using both fossil data and published substitution rates. Ancestral area estimation was performed on the phylogeny to define the contribution of the functions through time. Results: Accumulation of Theodoxus diversity in Anatolia over the Miocene–Pliocene transition is attributed to the museum function, but its contribution was small as only few divergence events occurred. The cradle function dominated during the Pliocene and Early Pleistocene, when most interspecific diversity built up and extant lineages in Anatolia were established. The sink function acted from the Middle Pleistocene to present-day, but with only a small contribution to the total extant Anatolian interspecific diversity. Main conclusion: Our results do not entirely mitigate the role glacial cycles played in species accumulation, but highlight Ice Ages may have been less effective in forcing temperate aquatic interspecific diversity into more opportune areas. The elevated diversity in refugia may rather be the result of earlier in situ diversification. Elevated interspecific diversity attributed to the legacy of glacially forced retreats may need to be re-evaluated in cases where refugia have long and complex geological histories such as Anatolia. These results highlight the importance of considering species accumulation through a temporal perspective to adequately explain present-day biodiversity patterns