This review focuses on rodent models of tremor, particularly those induced by pharmacological agents. Harmaline is one of the most frequently used tremor-generating drugs and harmaline-induced tremor ...is regarded as a model of essential tremor. Harmaline acts on inferior olive neurons, causing enhanced neuronal synchrony and rhythmicity in the olivocerebellar system. In addition, it selectively induces cerebellar Purkinje cell death, speculatively because of excessive glutamate release from nerve terminals of the olivocerebellar system onto Purkinje cells. Systemic administration of cholinomimetics can also produce generalized tremor, and muscarinic receptors on striatal neurons are thought to be the best candidate for the tremor-generating mechanism. On the other hand, dopaminergic neurotoxins, which are used in models of parkinsonism, have yet to be used for experimental analysis of tremor, because tremors induced by dopamine depletion in rodents are less remarkable than those induced by harmaline or cholinomimetics. Recently developed gamma-aminobutyric acid (GABA)(A) receptor alpha-1 subunit knockout mice exhibit postural and kinetic tremors, and clearly reproduce the features of essential tremors. Although from a phenomenological point of view, rodent models of tremor cannot entirely mimic human tremor disorders, they have useful advantages in the analysis of pathophysiological mechanisms underlying tremor. Development of convenient and reproducible methods for evaluating rodent tremor is therefore recommended.
Objective To determine the prevalence of fatigue and factors associated with fatigue in patients with Parkinson's disease (PD). Methods Fatigue was evaluated using the PD Fatigue Scale, a self-report ...questionnaire consisting of 16 statements describing the severity of fatigue symptoms. Patients were also evaluated using the Unified PD Rating Scale, Zung Depression Scale, the Epworth Sleepiness Scale, the PD Questionnaire-39 (PDQ-39) for assessing quality of life (QOL), and the Apathy Scale. Patients We examined 46 consecutive outpatients clinically diagnosed with PD, excluding patients with cognitive impairment. Results Fatigue was present in 22 (48%) patients. Multiple logistic regression analysis indicated that only QOL-scores and Apathy Scale scores were significant independent variables related to the presence of fatigue. Conclusion Fatigue is a common symptom in patients with PD, and it is a symptom closely related to impaired QOL.
Objective Carpal tunnel syndrome (CTS) severity increases with age. Ultrasonographic measurement of the median nerve cross-sectional area (CSA) is an additional or complementary method for CTS ...diagnosis. The present study was aimed to investigate the diagnostic significance of median nerve CSA in various age groups of CTS patients. Methods The subjects were patients with electrophysiologically confirmed CTS and age-matched controls. Sonographic measurements of the median nerve CSA were performed. Results A total of 279 hands of 175 patients with CTS and 50 normal hands were examined. CSA was correlated with distal motor and sensory latencies of the median nerve and severity of CTS. CTS severity increased with age, particularly in patients over 80; however, their median nerve CSA was not enlarged regardless of their high severity of CTS. Conclusion Although the median nerve CSA is a useful diagnostic measurement for CTS, it should be emphasized that its diagnostic significance might be limited in aged patients. In particular, in very elderly patients, careful evaluation of CTS severity is necessary.
Abstract
Our objective was to evaluate diaphragm thicknesses during respiration by ultrasonography, and compare with conventional measurements of respiratory functions in patients with amyotrophic ...lateral sclerosis (ALS). Thirty-six consecutive ALS patients and 19 age-matched healthy volunteers participated. Ultrasonography of the diaphragm in the zone of apposition was performed. Maximal diaphragm thickness during the maximal inspiratory effort (DTmax) and minimum diaphragm thickness at the end expiratory position (DTmin) were measured using ultrasonography. The thickening ratio (TR), defined as the ratio of DTmin to DTmax, was calculated. All patients underwent conventional pulmonary function testing. Arterial blood gas analysis was also performed. The diaphragm was clearly identifiable by ultrasonography. DTmax, DTmin and the TR were all significantly decreased in ALS patients with %VC (vital capacity) < 80, compared with those in either ALS patients with %VC ≥ 80 or healthy controls. DTmax, DTmin and the TR were all significantly correlated with %VC. In addition, significant inverse correlations were found between all three parameters and pCO2. The inter-observer reliability of measurements of diaphragm thickness was high. In conclusion, sonography of the diaphragm can provide additional or complementary information for assessing respiratory functions in patients with ALS.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Cells of the neural stem cell lineage in the adult subventricular zone (SVZ) respond to brain insult by increasing their numbers and migrating through the rostral migratory stream. However, in most ...areas of the brain other than the SVZ and the subgranular zone of the dentate gyrus, such a regenerative response is extremely weak. Even these two neurogenic regions do not show extensive regenerative responses to repair tissue damage, suggesting the presence of an intrinsic inhibitory microenvironment (niche) for stem cells. In the present study, we assessed the effects of injection of clustered ephrin-A1-Fc into the lateral ventricle of rats with unilateral nigrostriatal dopamine depletion. Ephrin-A1-Fc clustered by anti-IgG(Fc) antibody was injected stereotaxically into the ipsilateral lateral ventricle of rats with unilateral nigrostriatal lesions induced by 6-hydroxydopamine, and histologic analysis and behavioral tests were performed. Clustered ephrin-A1-Fc transformed the subventricular niche, increasing bromodeoxyuridine-positive cells in the subventricular area, and the cells then migrated to the striatum and differentiated to dopaminergic neurons and astrocytes. In addition, clustered ephrin-A1-Fc enhanced angiogenesis in the striatum on the injected side. Along with histologic improvements, behavioral derangement improved dramatically. These findings indicate that the subventricular niche possesses a mechanism for regulating both stem cell and angiogenic responses via an EphA-mediated signal. We conclude that activation of EphA receptor-mediated signaling by clustered ephrin-A1-Fc from within the lateral ventricle could potentially be utilized in the treatment of neurodegenerative diseases such as Parkinson's disease.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The relationship between varicella-zoster virus (VZV)-associated myelitis and aquaporin-4 immunoglobulin-G (AQP4-IgG) remains unknown.
We report a case of acute radiculomyelitis with longitudinal ...extensive hyperintensity signals traversing the brainstem until the upper thoracic cord in a 55-year-old healthy woman following herpes zoster infection in the left C4-T3 dermatome. VZV-specific IgG in the cerebrospinal fluid (CSF) and AQP4-IgG positivity on enzyme-linked immunosorbent assay (ELISA) were undetectable. Thus, she was diagnosed with immune-competent VZV radiculomyelitis. Forty-two months later, she experienced a relapse, and AQP4-IgG positivity was detected on ELISA. A cell-based assay (CBA) showed AQP4-IgG positivity not only at the time of recurrence but also retrospectively at 1 month after the initial symptoms. We concluded that AQP4-IgG-positive neuromyelitis optica spectrum disorder (NMOSD) was concurrent with VZV myelitis. After the second attack, she was treated with azathioprine and has had no relapse since then.
We reported a case of VZV radiculomyelitis with confirmed concurrent AQP4-IgG positivity. NMOSD induced by herpes zoster has been recently identified, but distinguishing it from VZV myelitis can be difficult and whether these two diseases aggravate each other is unknown. Awareness of the potentially varied presentation of VZV myelitis can enable earlier recognition and proper treatment.
Secondary cervical dystonia is induced by organic brain lesions involving the basal ganglia, thalamus, cerebellum, and brain stem. It is extremely rare to see cervical dystonia induced by a medullary ...lesion.
We report a case of an 86-year-old Japanese woman who developed cervical dystonia following lateral medullary infarction. She developed sudden-onset left upper and lower extremity weakness, right-side numbness, and dysarthria. Brain magnetic resonance imaging revealed an acute ischemic lesion involving the left lateral and dorsal medullae. A few days after her stroke, she complained of a taut sensation in her left neck and body, and cervico-shoulder dystonia toward the contralateral side subsequently appeared. Within a few weeks, it disappeared spontaneously, but her hemiplegia remained residual.
To date, to the best of our knowledge, there has been only one reported case of cervical dystonia associated with a single medullary lesion. It is interesting to note the similarities in the clinical characteristics of the previously reported case and our patient: the involvement of the dorsal and caudal parts of the medullary and associated ipsilateral hemiplegia. The present case may support the speculation that the lateral and caudal regions of the medulla may be the anatomical sites responsible for inducing cervical dystonia.
Objective There is growing interest in the use of transcranial sonography (TCS) of the substantia nigra (SN) in patients with Parkinson's disease (PD), as it has been reported that SN ...hyperechogenicity may be present in about 90% of PD patients. However, TCS of the SN has not been applied in Japanese patients, and its clinical potential has not been determined. Patients and Methods TCS of the SN was performed in patients with PD, progressive supranuclear palsy (PSP), multiple system atrophy (MSA), and essential tremor (ET), and age-matched controls. Ultrasound images of the SN were assessed using semi-qualitative estimation criteria by two investigators unaware of clinical diagnosis. Results SN hyperechogenicity was observed in approximately 83% of accessible SNs in Japanese PD patients. In comparison, SN hyperechogenicity was less frequently observed in healthy subjects or in patients with PSP, MSA, and ET. However, the rate of successful recording of the SN by TCS decreased prominently with advancing age, particularly in females. Conclusion The present study confirmed that TCS of the SN is potentially useful in the investigation of Japanese patients, and it provides a better differential diagnosis between PD and atypical parkinsonism. The recording failure of TCS in aged, particularly female subjects, may limit the clinical potential of TCS of the SN in Japanese patients.
Acute necrotizing encephalopathy is one of the most devastating neurological complications of influenza virus infection. Acute necrotizing encephalopathy preferentially affects the thalamus ...bilaterally, as does deep cerebral venous thrombosis, which can lead to misdiagnosis.
A 52-year-old Japanese woman infected with seasonal influenza B virus presented to the emergency care unit in our hospital with progressive alteration of her level of consciousness. Bilateral thalamic lesions were demonstrated by magnetic resonance imaging, leading to a tentative diagnosis of acute necrotizing encephalopathy. However, she had deep cerebral venous thrombosis, and the presence of diminished signal and enlargement of deep cerebral veins on T2*-weighted imaging contributed to a revised diagnosis of deep cerebral venous thrombosis. Anticoagulant therapy was initiated, leading to her gradual recovery, with recanalization of the deep venous system and straight sinus.
To the best of our knowledge, these results represent the first report of deep cerebral venous thrombosis associated with influenza infection. It is clinically important to recognize that deep cerebral venous thrombosis, although rare, might be one of the neurological complications of influenza infection. In the presence of bilateral thalamic lesions in patients with influenza infection, deep cerebral venous thrombosis should be considered in addition to acute necrotizing encephalopathy. Delays in diagnosis and commencement of anticoagulant therapy can lead to unfavorable outcomes.
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