Electrodiagnostic methods to verify Guillain-Barré syndrome subtypes in Istanbul: A prospective multicenter study

BACKGROUND AND AIMS

This study aimed to identify the clinical characteristics and electrodiagnostic subtypes of Guillain-Barré syndrome (GBS) in Istanbul.

METHODS

Patients with GBS were prospectively recruited between April 2019 and March 2022 and two electrodiagnostic examinations were performed on each patient. The criteria of Ho et al., Hadden et al., Rajabally et al., and Uncini et al. were compared for the differentiation of demyelinating and axonal subtypes, and their relations with anti-ganglioside antibodies were analyzed.

RESULTS

One hundred seventy-seven patients were included, 69 before the coronavirus disease 2019 pandemic (April 2019-February 2020) and 108 during the pandemic (March 2020-March 2022), without substantial changes in monthly frequencies. As compared with the criteria of Uncini et al., demyelinating GBS subtype diagnosis was more frequent according to the Ho et al. and Hadden et al. criteria (95/162, 58.6% vs. 110/174, 63.2% and 121/174, 69.5%, respectively), and less frequent according to Rajabally et al.'s criteria (76/174, 43.7%). Fourteen patients' diagnoses made using Rajabally et al.'s criteria were shifted to the other subtype with the second electrodiagnostic examination. Of the 106 analyzed patients, 22 had immunoglobulin G anti-ganglioside antibodies (14 with the axonal subtype). They had less frequent sensory symptoms (54.5% vs. 83.1%, p = 0.009), a more frequent history of previous gastroenteritis (54.5% vs. 22.9%, p = 0.007), and a more severe disease as compared with those without antibodies.

INTERPRETATION

Serial electrodiagnostic examinations are more helpful for accurate subtype diagnosis of GBS because of the dynamic pathophysiology of the disease. We observed no significant increase in GBS frequency during the pandemic in this metropolis.

The frontal planar QRS/T angle in patients with non-ischemic type late gadolinium enhancement on cardiac magnetic resonance

OBJECTIVE

Evaluation of myocardial fibrosis may offer an insight into underlying pathological mechanisms of ventricular arrhythmias. We intended to investigate the possible association between the presence and extent of myocardial fibrosis and ventricular repolarization heterogeneity based on frontal planar QRS/T angle.

PATIENTS AND METHODS

We retrospectively investigated patients in whom gadolinium-based contrast agent cardiac magnetic resonance imaging was performed due to the suspicion of any myocardial disease. Patients with non-ischemic type late gadolinium enhancement (LGE) were enrolled into this study. The association between presence and extent of myocardial LGE and frontal planar QRS/T angle defined as the absolute difference between QRS wave axis and T-wave axis on a resting 12-lead surface ECG was evaluated.

RESULTS

The frontal planar QRS/T angle was significantly higher in patients with myocardial fibrosis indicated by LGE compared to those without LGE (61.67 ± 40.70 vs. 37.27 ± 32.35, p < 0.001). LGE extent score assessed by visual 17-segment model was the only independent variable, which had a significant effect on frontal planar QRS/T angle [Unstandardized Coefficients B = 4.052, 95% CI [(2.025) - (6.079), p < 0.001].

CONCLUSIONS

In conclusion, this study showed that inhomogeneous areas of myocardium due to varying degrees of myocardial fibrosis might affect the electrical activity of the left ventricle, even with normal left ventricular dimensions and function.

Relationship of diffusion tensor imaging parameters with neurocognitive dysfunction in patients with Behcet's disease

Behcet's disease (BD) is a chronic, multisystemic, relapsing-remitting, progressive inflammatory disorder with unknown etiology. The aim of the study is to investigate the white matter integrity and subclinical brain parenchymal involvement in Behcet's subjects by utilizing diffusion tensor imaging (DTI) and to correlate apparent diffusion coefficient (ADC), fractional anisotropy (FA), mean diffusivity (MD), and radial diffusivity (RD) values measured from the diverse distinct anatomic locations with the disease duration time and neurocognitive function test results. Thirty-five adults with Behcet's disease and 21 age-matched healthy controls were enrolled in this study. Neurocognitive functions of the patients were evaluated with the Brief Repetable Battery-Neuropsychological tests (BRB-N). In both groups, DTI metrics were calculated from 19 different locations in the brain. The association between the DTI parameters and disease duration time and neurocognitive function test results were investigated. In Behcet's disease, at the cingulum and the splenium of the corpus callosum (SCC), FA values were significantly lower compared with the controls (p = 0.0015, p = 0.003, respectively). The ADC values of the corona radiata and RD values of superior longitudinal fasciculus and SCC were significantly higher than the controls (p = 0.023, p = 0.028, p = 0.006, respectively). Significant negative correlations were found between the FA values of cingulum, genu of corpus callosum (GCC), posterior limb of internal capsule (PLIC) and disease duration time (r = - 0.368; p = 0.029 and r = - 0.337; p = 0.048 and r = - 0.527; p = 0.001 respectively). All BD subjects performed significantly lower test scores on the spatial recall test (SPART) (p = 0.001). In addition, negative correlation was found between the MD values of the parietooccipital white matter and the selective reminding test (SRT) results (r = - 0.353; p = 0.037). Our DTI study presented microstructural alterations in the neurocognitive-related areas and BRB-N test results even in patients without neurological symptoms which may imply insidious neurological involvement.

Characteristic features of migraine in schoolchildren and adolescents and its relationship with autonomic nervous system disorders

OBJECTIVE

The studies about autonomic nervous system (ANS) disorders in adult migraineurs show conflicting results with limited data on ANS function in childhood and adolescence. This study aimed to investigate ANS function in childhood migraine.

PATIENTS AND METHODS

The migraine and control groups consisted of 35 migraineurs and 30 healthy children, respectively. In both groups, heart rate interval variation (RRIV) and sympathetic skin response (SSR) were used as noninvasive ANS function tests.

RESULTS

No significant differences in age and gender distribution were found between the study and control groups. A family history of migraine was seen in 65% patients in the study group and 20% in the control group. The duration, quality, frequency, and location of pain were variable; only 14.1% of the patients had sensory and visual aural symptoms. There was neither a significant difference in RRIV and SSR between migraine and control groups (p > 0.05) nor in heart rate responses to deep breathing (p = 0.83). The mean amplitude of SSR in children with migraine was smaller than that in the control group, but it did not reach a level of statistical significance.

CONCLUSIONS

In children with migraine, our results demonstrate no abnormal ANS function related to either the sympathetic or the parasympathetic nervous system.

Pregnenolone protects mouse hippocampal (HT-22) cells against glutamate and amyloid beta protein toxicity

In the present work we have examined whether the neurosteroid pregnenolone has any neuroprotective effects against glutamate and amyloid beta protein neurotoxicity using immortalized clonal mouse hippocampal cell line (HT-22). The neurosteroid pregnenolone protects HT-22 cells against both 5 mM glutamate and 2 microM amyloid beta protein induced cell death in a concentration dependent manner. Optimum protection was attained at 500 nM pregnenolone, against both 5 mM glutamate as well as 2 microM amyloid beta protein induced HT-22 cell death. Furthermore, using confocal immunoflourescence microscopy we observed that 20 hours of treatment with 5 mM glutamate resulted in intense nuclear localization of the glucocorticoid receptor (GR) in HT-22 cells as compared to control untreated cells. Interestingly, 500 nM pregnenolone treatment for 24 hours, followed by 20 hours treatment with 5 mM glutamate resulted in dramatic reduction in GR nuclear localization. These results show that (i) pregnenolone has neuroprotective effects against both glutamate and amyloid beta protein neuropathology and (ii) prevention of glucocorticoid receptor (GR) localization to the nucleus may be involved in the observed neuroprotective effects of pregnenolone against glutamate neurotoxicity.

Heat shock preconditioning and pretreatment with glucocorticoid antagonist RU 486 protect rat myogenic cells H9c2 against glutamate-induced cell death

We have observed that the treatment of rat-heart derived H9c2 myoblasts for 20 h with the excitatory amino acid glutamate resulted in cell death in a dose dependent manner as determined by LDH release. The optimum cardiotoxicity was seen at 25 mM glutamate. Preconditioning with either sublethal heat shock (42 degrees C for 30 min) or pretreatment with 500 nM of the glucocorticoid antagonist RU 486 for 24 h almost completely protected H9c2 cells against subsequent 20 h treatment with 25 mM lethal glutamate. In addition, we have observed that glutamate treatment resulted in intense nuclear localization of glucocorticoid receptors (GR) in H9c2 cells as judged by the confocal immunofluorescence microscopy. Furthermore, pretreatment with either heat shock or RU 486 followed by glutamate treatment resulted in dramatic decrease in GR nuclear localization which was almost comparable to that observed with control untreated cells. In conclusion, we have shown for the first time using H9c2 cells that (i) protection from glutamate cardiotoxicity occurs with prior treatment with sub lethal heat shock or RU 486 and (ii) these measures down regulate the intense nuclear localization of GR induced by glutamate. The block to GR nuclear localization is likely to be involved in cardioprotective effects offered against glutamate toxicity by pretreatment with heat shock or RU 486.

Biological effects of long-term caloric restriction: adaptation with simultaneous administration of caloric stress plus repeated immobilization stress in rats

In the present study, we have established the biological effects during 8 weeks of (i) caloric restriction (Cal) and (ii) simultaneous administration of Cal plus 2 hr daily immobilization stress using male Sprague-Dawley rats. Animals were divided into three equal groups: (i) ad libitum fed, (ii) 30% restriction of food intake of the ad libitum diet, and (iii) 30% restriction of food intake plus 2 hr daily immobilization stress. Caloric-restricted animals gained only 30% of the total body weight of the unrestricted animals but received 70% of the food of those rats. Cal animals showed a significant loss in their relative liver and-thymus weight and a significant gain in their relative adrenal and testis weight as compared to the control animals. Cal animals had almost 2-fold higher levels of plasma corticosterone levels with a dramatic decrease in the total glucocorticoid receptor (GR) levels in the liver, thymus, heart, and testis as compared to ad libitum fed control animals. Interestingly, Cal animals showed higher levels of lipid peroxidation in both the liver and heart, indicating increased oxidative activities in these tissues when compared with the control animals. In addition, Cal animals had increased heat shock protein 70 (HSP 70) content in the testis. Surprisingly, hardly any significant differences were observed in either total body weight gain, organ weights, plasma corticosterone levels, or lipid peroxidation between Cal animals and Cal plus immobilization-stressed animals. The results obtained suggest that (i) several stress-related responses such as inhibition of total body weight gain, increased adrenal weight, decreased thymus weight, increased plasma corticosterone, and lipid peroxidation levels in the liver and heart are associated with Cal, but (ii) no additional effects were observed on the parameters that were measured when two stress regimens were given simultaneously, suggesting that animals subjected to two stress regimens can protect themselves by controlling their stress-related thresholds of response through adaptation.

The environmental estrogenic compound bisphenol A exerts estrogenic effects on mouse hippocampal (HT-22) cells: neuroprotection against glutamate and amyloid beta protein toxicity

We have examined using immortalized clonal mouse hippocampal cell line (HT-22) whether the environmental estrogenic compound bisphenol A (BPA), like estrogen, has any neuroprotective effect against glutamate and amyloid beta protein-induced neurotoxicity. BPA protects HT-cells against both 5 mM glutamate and 2 microM amyloid beta protein-induced cell death in a dose dependent manner. Optimum protection was attained at 1 microM and 500 nM BPA against 5 mM glutamate and 2 microM amyloid beta protein-induced HT-22 cell death, respectively. Using confocal immunoflourescence microscopy technique, we observed that 20 h of treatment with 5 mM glutamate resulted in intense nuclear localization of the glucocorticoid receptors (GR) in HT-22 cells as compared to control untreated cells. Interestingly, 1 microM BPA treatment for 24 h, followed by 20-h treatment with 5 mM glutamate, resulted in dramatic reduction in GR nuclear localization. We conclude that: (i) BPA mimics estrogen and exerts neuroprotective effects against both neurotoxins used; (ii) BPA inhibits enhanced nuclear localization of GR induced by glutamate; and (iii) HT-22 cells provide a good in vitro model system for screening the potencies of various environmental compounds for their estrogenic activity.

Biological effects of single and repeated swimming stress in male rats: beneficial effects of glucocorticoids

We have examined the biological effects of single (45 min at 22 degrees C) and repeated swimming stress (45 min at 22 degrees C for 7 d) using male Sprague-Dawley rats. Repeated swimming for a week resulted in a significant inhibition in total body weight (25%) as compared to control unstressed animals. There was significant increase in adrenal and kidney relative weight and decreases in relative thymus weight in repeated swimming-stressed animals as compared to control animals. Repeated swimming stress resulted in almost threefold increase in plasma corticosterone levels with concomitant dramatic decrease in total glucocorticoid receptor (GR) levels in liver, thymus, and heart as compared to control unstressed animals. Interestingly, single swimming stress resulted in a significant elevation in lipid peroxidation levels in the liver and heart. In contrast, there was no change in the lipid per oxidation levels in the liver and heart between chronic stressed and control unstressed animals. Finally, both single and repeated swimming-stress animals had almost 50% reduction in plasma triglyceride levels as compared to control unstressed animals. It is concluded that elevated plasma corticosterone levels by downregulating GR during repeated swimming stress exerts beneficial effects in rats by retarding the total body weight gain and lowering plasma triglyceride levels without affecting free-radicals-induced oxidative stress.

Anti-stress effects of dehydroepiandrosterone: protection of rats against repeated immobilization stress-induced weight loss, glucocorticoid receptor production, and lipid peroxidation

In the present study, we have (i) examined the biological effects of repeated immobilization stress, and (ii) tested the hypothesis that the adrenal steroid hormone dehydroepiandrosterone (DHEA) is an anti-stress hormone, using male Sprague-Dawley rats. Rats (N = 6) were divided into the following four groups: (i) control, (ii) repeated immobilization stress (2 hr daily, for 60 days), (iii) repeated immobilization stress (2 hr daily, for 60 days) plus daily i.p. administration of 5 mg DHEA/0.1 mL DMSO, and (i.v.) daily i.p. administration of 5 mg DHEA/0.1 mL DMSO alone. Results obtained showed that repeated immobilization stress resulted in a significant (25%) inhibition in body weight gain, a significant increase in adrenal weight, an increase in glucocorticoid receptor (GR) in the liver, thymus, and spleen, decreased plasma triglyceride levels, and increased lipid peroxidation in the liver and heart as compared with control unstressed animals. Interestingly, DHEA administration resulted in a significant reversal in stress-induced inhibition in body weight gain, adrenal weight, GR levels in liver, thymus, and spleen, and lipid peroxidation levels in the liver and heart. In addition, animals treated with DHEA alone without stress showed a significant (15%) inhibition in body weight gain and an almost 60% decrease in plasma triglyceride levels as compared with control unstressed animals. It is concluded that DHEA acts as an anti-stress hormone in rats, as shown in its antagonizing the effects of repeated immobilization stress on total body weight, adrenal weight, GR levels, and free radical generation.