The predictive value of serum testosterone level on the functional outcomes after acute ischemic stroke in males.

INTRODUCTION: We aimed to evaluate the predictive value of sex hormone levels on 3-month functional outcomes after acute ischemic stroke (AIS) in males. MATERIALS AND METHODS: A total of 110 male AIS patients were included in this prospective study. Serum levels of testosterone and estradiol were measured at admission. The National Institutes of Health Stroke Scale (NIHSS) and the modified Rankin Scale (mRS) were measured at admission and after 3 months. A mRS score ≥3 was considered as a poor functional outcome. RESULTS: The median age of the 110 subjects was 62.0 [23.3] years (range 35-93 years). Univariate logistic regression revealed that bioavailable testosterone, free testosterone, age, NIHSS at admission, mRS at admission, and prior ischemic stroke were associated with a poor functional outcome (mRS score ≥3) at 3 months. In multivariate analysis, only age, NIHSS at admission, and mRS at admission were independent predictors. CONCLUSIONS: After controlling the covariates, bioavailable and free testosterone levels are not associated with the 3-month mRS in male patients with AIS. Age, NIHSS at admission, and mRS at admission are robust predictors for the functional outcomes.

The Association of Serum Testosterone Levels With Recurrence and Mortality After Acute Ischemic Stroke in Males.

The current study aimed to investigate whether low testosterone predicted the recurrence and clinical outcomes after acute ischemic stroke (AIS) in males. From June 2015 through August 2017, the study prospectively enrolled 110 male AIS patients. All received detailed evaluations at admission and were followed for at least 1 year. The cumulative incidence, overall survival, length of hospital stay, and the percentage of previous stroke were compared between subjects with testosterone <440 ng/dl and >440 ng/dl. The median age was 62 years (range, 35-93 years). The median serum testosterone at admission was 438 [203] ng/dl (range, 44-816 ng/dl); 55 patients (50%) had testosterone <440 ng/dl and were considered as low testosterone. The median follow-up was 23 months. During the period, 12 recurrences and 10 deaths occurred. The 1-year and 3-year cumulative recurrence rate were 8.3% and 11.9%, respectively; the 1-year and 3-year overall survival were 96.3% and 84.6%, respectively. The cumulative recurrence rates were similar between the two testosterone groups (log-rank test, p = .88). Low testosterone was associated with poor survival with marginal significance (log-rank test, p = .079). Men with low testosterone had a higher percentage of previous stroke (29.1% versus 12.7%, p = .035). The mean lengths of hospital stay were similar between the two testosterone groups (16.6 ± 15.8 days versus 14.0 ± 10.6, p = .31). Total testosterone at admission fails to predict stroke recurrence. However, men with low testosterone at admission are more likely to have previous stroke and may have a higher all-cause mortality rate after AIS.

Paired nociceptive blink stimuli can facilitate trigeminofacial circuit at a long inter-stimulus interval.

BACKGROUNDS: Conditioned responses of paired nociceptive blink reflex (nBR) can reflect the excitability of trigeminofacial circuit. In the present study, we studied paired homotopic nBR with different inter-stimulus intervals (ISI). By monitoring different ISIs and consequential conditioned R2 of nBR, we aimed to investigate the impact of ISIs on the recovery cycle of nBR in normal individuals. METHODS: Twelve healthy volunteers (mean age: 29.9 ± 7.0 years; M/F: 7/5) were enrolled in this study. After individuals' reflex threshold was determined, triple pulses were given in pairs with ISIs 125 to 10000 milliseconds randomly. We calculated the ratio of conditioned and unconditioned nBR area-under-curve (AUC) (defined as recovery index), and amplitude of each ISI. RESULTS: The average latency of unconditioned nR2 is 42.6 ± 5.5 ms, with amplitude of 53.4 ± 43.9 µV and the AUC of 563.5 ± 480.6 ms·µV. The conditioned nBR/unconditioned nBR response ratio was less than 100% while the ISI is shorter than 1667 ms, suggesting an inhibited conditioned response. The recovery index and the amplitude of conditioned nBR gradually increased with increasing ISI. The recovery index was greater than 100% at ISI of 10 s (p = 0.005), implying full recovery and facilitation of conditioned nBR. CONCLUSION: Our study established the time-dependent dynamic recovery curve of paired nBR. The facilitated nBR at ISI longer than 10 s might be associated with temporal summation to the facial motor neurons after repeated stimuli. Our study results provided potential applications for patients with pain disorders involving trigeminofacial region.

Multiple cerebral and cerebellar infarcts as the first clinical manifestation in a patient with Churg-Strauss syndrome: case report and literature review.

PURPOSE: Churg-Strauss syndrome (CSS) is a rare autoimmune disease with small-vessel vasculitis. Neurological manifestation of CSS is common. Central nervous system is less frequently involved than that of peripheral nervous system. CASE REPORT: We report a case of 60-year-old man who presented with acute onset of right hemiparesis and impaired cognition. The presence of hypereosinophilia, asthma, sinusitis and extravascular eosinophil accumulation led to the diagnosis of Churg-Strauss syndrome. Brain magnetic resonance imaging (MRI) revealed multiple infarcts in bilateral cerebral and cerebellar hemispheres. The neurophysiology study did not reveal peripheral neuropathy. The patient was effectively treated with methylprednisolone, cyclophosphamide and warfarin. CONCLUSION: Symptoms and signs of central nervous system can be the initial neurological manifestation of CSS patients. CSS should be considered while patients have stroke and hypereosinophilia. In our patient, there is a good response to timely steroid, immunosuppressant and anticoagulant therapies.

Preserved motor-evoked potentials but without good motor recovery in a patient with decerebrate rigidity.

The corticospinal tract is not incriminated in decerebrate rigidity (DR). However, this has not yet been proven in humans. We applied transcranial magnetic stimulation (TMS) in a decerebrate patient to support the hypothesis. A patient suffering from pontine hemorrhage with the fourth ventricular extension was admitted unconscious and in a decerebrate posture. Five days later, she regained consciousness but remained in a decerebrate posture. Motor-evoked potentials (MEPs) to TMS were measured 1 week after she had regained consciousness, and this provoked muscle responses in her hands and feet bilaterally. During the follow-up, the patient's muscle tone became persistently flaccid, although her strength increased to varying degrees in different body and limb muscles. She remained bedridden for 3 years after the stroke and could neither turn on the bed by herself nor perform skilled movements using her hands. The findings of TMS confirmed the animal studies in that the mechanism of decerebrate rigidity did not come through a damage of the corticospinal pathway. This also implies that a preserved corticospinal tract function cannot guarantee a good motor recovery in a stroke patient.

Fatigue in colchicine myopathy: a study of transcranial magnetic stimulation.

BACKGROUND: Transcranial magnetic stimulation (TMS) is a noninvasive method to assess brain physiology and plasticity. TMS has shown that nervous system excitability may be altered in myopathy, and it presents with motor disinhibition on cortical and subcortical levels. Eight patients who had colchicine myopathy were observed to have fatigue, but they did not have significant weakness. This study investigated whether there was central reorganization to compensate for their muscle strength. METHODS: TMS was applied to study the central compensative mechanism. The TMS parameters included motor evoked potentials, central conduction time, cortical silent period and intracortical inhibition of paired TMS paradigms. RESULTS: TMS results did not show any significant differences between patient and control groups. CONCLUSION: Although central reorganization may occur in patients with hereditary myopathy to compensate for muscular strength, our study did not find any change in cortical excitabilities in acquired myopathy due to colchicine. Muscle fatigue may precede weakness as an early symptom of myopathy.

Fatigue as the only clinical manifestation of colchicine induced myopathy.

PURPOSE: Fatigue may be induced by drug. Here, we reported that patients had fatigue after medication with colchicines. METHOD: Eight patients (8 Males, age: 42-72 years old) had fatigue but without weakness as their chief complaints. They all described an inability to maintain a sustained effort, which was ameliorated by rest. RESULTS: The course of fatigue was insidious and progressive (mean 3.1 2.3 months, range 1-7 months) along with medication of colchicines (mean 20.3 5.5 months, range 11-28 months). Fatigue severity scale (patient: before drug withdrawal 5.41 0.19; 4 weeks after drug withdrawal 2.46 0.28; control 2.12 0.45) showed fatigue as their most disabling symptom, sometimes preventing them to carry on professional as well as socio-familial activities. The plasma creatine kinase elevated in these 8 patients before withdrawal of colchicines and returned to normal range in each subject 4 weeks after drug withdrawal. A probable diagnosis of drug-induced fatigue was made when symptom subsided after colchicines were discontinued. CONCLUSION: It is emphasized that side effect of drug should be considered as a differential diagnosis of fatigue in patients having colchicines. Early recognition and diagnosis will prevent serious muscle damage.

Gabapentin reduces neurovisceral pain of porphyria.

PURPOSE: Gabapentin is well known for pain control. Here, we report that gabapentin is a good adjunct for visceral pain in a porphyria patient. CASE REPORT: A young female was admitted due to acute abdomen. On admission, she was noted to have hyponatremia, tachycardia, and hypertension. Then, she had episodes of seizure and confusion. Gabapentin was prescribed for the control of seizure and pain before the diagnosis of acute intermittent porphyria was confirmed. Seizure did not occur after gabapentin. Pain severity also significantly reduced with visual analogue scale from 10 to 4. The severity of pain rebounded after gabapentin was withdrawn. When the diagnosis was proved, the neurovisceral pain further decreased with combination of morphine and gabapentin and subsided after treatment with hematin. CONCLUSION: Our report indicates that gabapentin can be considered in porphyria patients, especially when patients had seizures or acute abdomen, when morphine is not available or contraindicated, when abdomen pain transforms as chronic pattern, and when neuropathic pain occurs in extremities.

High-frequency somatosensory evoked potentials of normal subjects.

BACKGROUND: We investigated the characteristics and correlates of high-frequency oscillations (HFOs) of somatosensory evoked potentials (SEPs). METHODS: Subjects were 26 healthy volunteers. SEP was recorded from the hand sensory area contralateral to the median nerve stimulated at the wrist. HFOs were obtained by digitally filtering raw SEPs from 500 to 1000 Hz, and their amplitudes and area-under-curve, duration, and number of negative peaks were measured. We also measured amplitudes of the N20 onset-peak (N20o-p), and N20 peak-P25 peak (N20p-P25p). RESULTS: In normal subjects, several oscillation potentials were observed at the latency of 0 to 10 ms after the onset of N20. The mean number of negative peaks of total HFOs was 6.96 +/- 1.20 (early phase 3.36 +/- 0.62; late phase 3.60 +/- 1.14). The mean maximal amplitude of total HFOs was 0.16 +/- 0.07 microV (early phase 0.14 +/- 0.05 microV; late phase 0.15 +/- 0.07 microV). The mean duration of total HFOs was 10.19 +/- 1.98 ms (early phase 4.89 +/- 1.04 ms; late phase 5.31 +/- 1.95 ms). The mean area of total HFOs was 567.54 +/- 227.86 microV x ms (early phase 268.46 +/- 98.40 microV x ms; late phase 299.08 +/- 183.44 microV x ms). The amplitude ratio was 7.30 +/- 3.32% of HFOearly/N20o-p, 3.19 +/- 1.55% of HFOlate/N20-P25, and 3.54 +/- 1.84% of HFOtotal/N20p-P25. During the test, the amplitude of HFO was significantly reduced by drowsiness. CONCLUSIONS: In waking subjects, a burst of low-amplitude HFO can be extracted from the N20.

Placenta-derived multipotent cells differentiate into neuronal and glial cells in vitro.

Stem cells have great potential for clinical application because of their self-renewal property and ability to differentiate into many types of cells, but because there are ethical and biological limitations with current sources of stem cells, the search continues for more suitable sources of multipotent cells. We have reported previously on a population of multipotent cells isolated from the human term placenta, an ethically unproblematic and easily available source of tissue. These placenta-derived multipotent cells (PDMCs) can differentiate into lineages of mesenchymal tissues, including osteoblasts and adipocytes, as well as non-mesenchymal tissue of neuron-like cells. We further examined the ability of PDMCs to differentiate into all 3 types of neural cells--neurons, astrocytes, and oligodendrocytes--under various induction conditions, including retinoic acid (RA), 1-methyl-3-isobutylxanthine (IBMX), and co-culture with neonatal rat brain cells. PDMCs exhibited outgrowth of processes and the expression of neuron-specific molecules such as neuron-specific enolase upon induction. Co-culture with neonatal rat brain cells also induced neural differentiation. Our results indicate that PDMCs can be differentiated into neural cell types of the human nervous system upon exposure to RA, IBMX, or primary rat brain cells.

Gabapentin for decerebrate rigidity: a case report.

A 48-year-old woman suddenly lost consciousness as a result of a right rostral pontine tegmentum haemorrhage. The patient presented with decerebrate rigidity (DR) and regained full consciousness 5 days after the initial onset. The patient was given gabapentin 1200 mg/day nasogastrically and her DR significantly improved, although other antiepileptic drugs such as phenytoin and carbamazepine were given in larger dosages to decrease muscle hypertonicity. The patients' preserved consciousness and motor-evoked potentials to transcranial magnetic stimulation indicated a derangement of the extrapyramidal tracts with preservation of the pyramidal tracts. This case report discusses the possible mechanisms of action of gabapentin in DR.

Effect of sacral neuromodulation on the spinal nociceptive reflex of patients with idiopathic overactive bladder.

Objectives. Sacral root stimulation (SRS) is a technique to restore the idiopathic overactive bladder (IOB). However, its mechanism of action is yet to be elucidated. Hence, we studied whether SRS restored IOB through the mechanism of spinal neuromodulation. Materials and Methods. Six IOB patients and 10 healthy volunteers were included in the study. The spinal nociceptive reflex was used as the index of spinal excitability and was evoked by electrical stimulation at the foot, with recording at the ipsilateral tibialis anterior. Results. IOB patients had increased spinal excitability to somatic nociceptive stimuli of the lower limbs. This spinal excitability decreased and bladder function improved after SRS, an effect that outlasted actual stimulation by at least 30 min. Conclusions. Our results showed that spinal excitability was increased in response to somatic nociceptive afferents in IOB patients. SRS restored bladder function, at least, in part, through spinal neuromodulation.

Multimodal evoked potentials of Kennedy's disease.

BACKGROUND: Kennedy's disease (KD) is an X-linked recessive polyglutamine disease. Traditionally, it is a lower motor neuron syndrome with additional features such as gynecomastia and tremor. Sensory symptoms are minimal if ever present. We used multimodal evoked potential (EPs) tests to study the distribution of the involvement of the disease. METHODS: Visual, brainstem auditory, somatosensory and motor EPs were studied in six KD patients. All of them had typical presentations and had been proved genetically. RESULTS: Abnormal findings were noted as follows: prolonged peak latencies of visual EPs, increased hearing threshold level, inconsistent brainstem auditory EPs, decreased amplitudes of cortical potentials of somatosensory EPs, and increased motor threshold to transcranial magnetic stimulation. CONCLUSIONS: Our multimodal EP studies showed that KD involved multiple levels of the nervous system. It implies the widespread effects of the mutant androgen receptors.

Brainstem excitability is increased in subjects with palmomental reflex.

BACKGROUND/PURPOSE: The palmomental reflex (PMR) is a brief contraction of the mentalis muscles caused by a scratch over the thenar eminence, i.e. a brainstem reflex to afferents of upper limb. Using electrophysiologic methods, we studied the characteristics of brainstem excitability in PMR subjects. METHODS: Ten healthy PMR subjects were included in the study. Brainstem excitability was assessed with electrical stimulation at the trigeminal nerve, median nerve, ulnar nerve, and sural nerve with recordings at the mentalis muscles. A comparison was made by the probability between the mechanical scratch and the electrical stimulation to evoke the visible muscle contraction of mentalis. RESULTS: An electrical stimulus was able to elicit mentalis muscle responses (MMR(electrical)) in all the subjects if the stimulus was of sufficient strength. Using electrical stimulation, the median nerve at the wrist was the best site to evoke MMR(electrical). However, in PMR subjects, the probability of MMR(electrical) to median nerve stimulation was less than that of MMR(scratch), i.e. the clinical findings of PMR. Significantly lower thresholds and higher amplitudes were noted in PMR subjects only when the median nerve was stimulated. The onset latency did not show any difference between the two groups despite the stimulation sites. CONCLUSION: The facial motor neurons to median nerve stimulation are more sensitive in PMR subjects. In healthy PMR subjects, this indicates that the excitability increases only in the specific neuronal circuits between the lower cervical spinal cord and the facial motor nucleus in the rostral medulla. MMR(electrical) is a physiologic phenomenon, and PMR is a sign of increased brainstem excitability.

Side of the stimulated ear influences the hemispheric balance in coding tonal stimuli.

OBJECTIVE: To evaluate whether the side of stimulated ear affects the hemispheric asymmetry of auditory evoked cortical activations. METHODS: Using a whole-head neuromagnetometer, we recorded neuromagnetic approximately 100 ms responses (N100m) in 21 healthy right-handers to 100 ms 1 kHz tones delivered alternatively to left and right ear. RESULTS: Although the peak latencies of N100m were shorter in contralateral than in ipsilateral hemisphere, the difference was significant only for the left ear stimulation. Based on the relative N100m amplitudes across hemispheres, the laterality evaluation showed a rightward predominance of N100m activation to tone stimuli, but the lateralization toward the right hemisphere was more apparent by the left than by the right ear stimulation (laterality index: -0.27 versus -0.10, p=0.008). Within the right hemisphere, the N100m was 2-4 mm more posterior for left ear than for right ear stimulation. CONCLUSIONS: The hemispheric asymmetry in auditory processing depends on the side of the stimulated ear. The more anterior localization of right N100m responses to ipsilateral than to contralateral ear stimulation suggests that there might be differential neuronal populations in the right hemisphere for processing spatially different auditory inputs.

Neurotoxicity of nitrous oxide: multimodal evoked potentials in an abuser.

INTRODUCTION: Nitrous oxide (N2O) damages the nervous system of chronic abusers. Multimodal evoked potentials (EPs) can help document the electrophysiological abnormalities of N2O abusers and its distribution in the nervous system. CASE REPORT: A 41-year-old male N2O abuser had used N2O (4-5 cans/per day, about 2000 ml/can) for more than 10 years. He complained of progressive motor clumsiness and distal paresthesia in the four limbs. Abnormal laboratory tests were megaloblastic red blood cells (102.3 fL, normal 80-94 fL) and serum vitamin B12 concentration of 143 pg/nL (normal 160-970 pg/nL). An MR image did not show significant findings in the brain but demonstrated conspicuous changes in the posterior and lateral columns at the C2-C7 level, in accordance with the anatomical lesions of the subacute combined degeneration of the spinal cord. In addition to sensori-motor axonal polyneuropathy, multimodal EPs showed abnormal visual EPs with prolonged peak latencies of P100, abnormal brainstem auditory EPs characterized by delayed wave V and difficulty in the recognition of waves I and III, abnormal somatosensory EPs with significant decreased peak amplitudes of cortical potentials bilaterally, and abnormal motor EPs to transcranial magnetic stimulation with prolonged central motor conduction time. CONCLUSION: Our studies document electrophysiological abnormalities that may be attributed to N2O and indicate that N2O may indirectly involve multiple levels of the nervous system.

Transcranial magnetic stimulation after conditioning stimulation in two adrenomyeloneuropathy patients: delayed but facilitated motor-evoked potentials.

Two male patients were diagnosed with adrenomyeloneuropathy. Their chief problems were progressive spastic paraparesis, sensory impairment, hyperpigmentation and testis atrophy. Transcranial magnetic stimulation (TMS) does not easily elicit motor-evoked potentials (MEPs) in patients with a central nervous system dysfunction, even though a few methods, such as contraction of the target muscles and the Jendrassik maneuver (JM), are used in the attempt to facilitate them. In these two patients, we used a conditioning method (prior electrical stimulation over the cutaneous nerve of the left index finger) in order to facilitate MEPs, elicited by TMS, in the left tibialis anterior muscle. In patient 1, facilitation of MEPs was present at conditioning-test (C-T) intervals in the range 60-220 ms, with the maximal MEP recorded at C-T 160 ms; in patient 2, it occurred in the C-T interval range 110-140 ms, with the maximal MEP recorded at C-T 130 ms. By means of conditioning electrical stimulation, we can facilitate MEPs elicited by TMS in those subjects in whom MEPs are minimal or difficult to elicit even using the conventional JM or muscle contraction. The facilitation of MEPs by conditioning stimuli allowed us not only to assess central motor conduction time, but also to demonstrate the preserved continuity of the corticospinal tract in these two patients.

Mentalis muscle responses to median nerve stimulation.

Electrical stimulation may produce excitation or inhibition of the motor neurons, as represented the blink reflex and masseter silent period in response to trigeminal nerve stimulation. Clinically, a light touch on the palm may evoke a mentalis muscle response (MMR), i.e. a palmomental reflex. In this study, we attempted to characterize the MMR to median nerve stimulation. Electrical stimulation was applied at the median nerve with recordings at the mentalis muscles. An inhibition study was done with continuous stimuli during muscle contraction (I1 and I2 of MMRaverage). Excitation was done with a single shot during muscle relaxation (MMRsingle) or by continuous stimuli during muscle contraction (E1 and E2 of MMRaverage). The characteristic differences between MMRaverage and MMRsingle were as follows: earlier onset latencies of MMRaverage (MMRaverage < 45 ms; MMRsingle > 60 ms), and a lower amplitude of MMRaverage (MMRaverage < 50 microV; MMRsingle > 150 microV). The receptive field of MMRsingle was widespread over the body surface and that of MMRaverage was limited to the trigeminal, median and index digital nerves. Series of stimuli usually significantly decreased the amplitude of MMRsingle, as a phenomenon of habituation. On the other hand, it was difficult to evoke the earlier response (i.e. MMRaverage) without continuous stimuli and an average technique. MMRaverage had the components of both excitation (E) and inhibition (I); for example, E1-I1-E2-I2 or I1-E2-I2. E2 was the most consistent component. In patients with dorsal column dysfunction, median nerve stimulation could successfully elicit MMRsingle, but not MMRaverage. Contrarily, in patients with pain sensory loss, it was more difficult to reproduce MMRsingle than MMRaverage. It seemed that MMRaverage and MMRsingle did not have equivalents across the different modalities of stimulation.

Hydrocephalus associated with Guillain-Barre syndrome.

A 68-year-old man developed progressive four-limb weakness and areflexia 17 days after an influenza vaccination. He was diagnosed with Guillain-Barre syndrome (GBS), and remained ventilator dependent and bed-bound for 3 months, despite plasmapheresis and immunoglobulin infusion. However, cognitive impairment, excessive daytime sleepiness, and motor disability were still present, even when he was no longer ventilator dependent. Brain computerized tomography scan and isotope cisternography was consistent with normal pressure hydrocephalus. His motor control and cognitive function recovered almost completely after insertion of a ventriculoperitoneal shunt. Although hydrocephalus is not frequently associated with GBS, our case report indicates that brain imaging is necessary in GBS patients whose cognitive functions deteriorates after disease onset.