Current Journal of Neurology
Volume:11 Issue: 4, Winter 2012

Chronic daily headache (CDH) has gained little attention in functional neuro-imaging. When no structural abnormality is found in CDH, defining functional correlates between activated brain regions during headache bouts may provide unique insights towards understanding the pathophysiology of this type of headache. We recruited four CDH cases for comprehensive assessments, including history taking, physical examinations and neuropsychological evaluations (The Addenbrooke’s Cognitive Evaluation, Beck’s Anxiety and Depression Inventories, Pittsburg Sleep Quality Index and Epworth Sleepiness Scale). Visual analogue scale (VAS) was used to self-rate the intensity of headache. Patients then underwent electroencephalography (EEG), transcranial Doppler (TCD) and functional magnetic resonance imaging (fMRI) evaluations during maximal (VAS = 8-10/10) and off-headache (VAS = 0-3/10) conditions. Data were used to compare in both conditions. We also used BOLD (blood oxygen level dependent) -group level activation map fMRI to possibly locate headache-related activated brain regions. General and neurological examinations as well as conventional MRIs were unremarkable. Neuropsychological assessments showed moderate anxiety and depression in one patient and minimal in others. Unlike three patients, maximal and off-headache TCD evaluation in one revealed increased middle cerebral artery blood flow velocity, at the maximal pain area. Although with no seizure history, the same patient’s EEG showed paroxysmal epileptic discharges during maximal headache intensity, respectively. Group level activation map fMRI showed activated classical pain matrix regions upon headache bouts (periaqueductal grey, substantia nigra and raphe nucleus), and markedly bilateral occipital lobes activation. The EEG changes were of note. Furthermore, the increased BOLD signals in areas outside the classical pain matrix (i.e. occipital lobes) during maximal headaches may suggest that activation of these areas can be linked to the increased neural activity or visual cortex hyperexcitability in response to visual stimuli. These findings can introduce new perspective towards more in-depth functional imaging studies in headaches of poorly understood pathophysiology.

High sensitive C-reactive protein (hs-CRP) is a systemic inflammatory marker that is produced in a large amount by hepatocytes in response to interleukin-1 (IL-1), IL-6 and tumor necrosis factor after ischemic stroke. Measurement of hs-CRP in the first 24 hours of onset in 162 patients suffering from ischemic stroke was done. Relation of CRP with the risk of early mortality, National Institutes of Health Stroke Scale (NIHSS), stroke subtypes and other factors was determined. Regarding to ROC curve analysis, appropriate cut-off point for predicting patients’ short time mortality was equal to 2.15 mg/dl in this study. Significantly increased rate of mortality by 13.3 times was seen in patients with simultaneous CRP > 2.15 and NIHSS > 10. The Result of this study showed that there is a direct association between hs-CRP and mortality within the first week after stroke. Measuring hs-CRP within the first hours after stroke increases the predicting rate of early mortality risk with cut-off point of 2.15.

Learning and memory are the most intensively studied subjects in neuroscience. Various approaches have been used to understand the underlying cellular and molecular mechanisms. Numerous studies have shown that different sites of brain are involved in learning and memory mechanisms. Two sites of mammalian brain that show high density of these receptors are CA1 region of hippocampus and Purkinje cell layer of cerebellum. Twenty four Sprague-Dawley rats were used in 4 groups: Control-1 (intact without learning); control-2 (intact with learning); ovariectomy (OVX) without learning and OVX with learning. A shuttle box apparatus used for passive avoidance learning procedure. Immunohistochemical procedure was used for determination of NR1 subunit of N-methyl-D-aspartate (NMDA) receptor. Photoshop software was used for determination of color intensity. Immunohistological finding of this experiment indicated that OVX has a negative effect on density of NR1 subunit of NMDA receptors in two brain regions. Other finding of this study showed that passive avoidance learning significantly increased density of NR1 subunit of NMDA receptors in two brain regions. These results indicated that the sex hormone can modulate function and expression of the NR1 subunit of NMDA receptor in CA1 region of hippocampus and Purkinje cell layer of cerebellum.

The existence of a pathophysiological link between headaches and muscle activity pattern is still being debated. The purpose of this study was to investigate the effect of pain on the timing pattern of the masseter muscle in patients with tension-type headache (TTH) and migraine without aura (MOA). 57 women (22 controls, 19 MOA and 16 TTH) participated in the study. The electromyographic (EMG) activity of masseter during the open-close-clench cycle (OCC) was recorded in the interictal and ictal stages. In the interictal stage, the results showed no significant difference in EMG activity between patients and control groups. However, masseter muscles in subjects with TTH (both sides) and in MOA patients (left side) activated significantly earlier than the control in the ictal stage. The duration of left masseter was also significantly greater in the TTH than in the control group (P > 0.05). The findings of this study showed that activity pattern of masticatory muscles in headaches patients were affected by existence of pain. Furthermore, this study confirmed that temporal variables of EMG such as onset and duration rather than amplitude could be more reliable to identify altered activity pattern of muscles.

Patients with Parkinson's disease (PD) have different cognitive impairments. The goal of this study is the analysis of these changes in the mentioned patients. A cross-sectional study was performed on 87 patients with PD. Patients were given a questionnaire to gather data about their medical and living statuses. To assess cognitive assessment, SCOPA-COG (Scales for Outcome in Parkinson Cognition) was used by an expert cognitive neuroscientist. The age inversely correlated to memory and learning (P < 0.01). Education level correlated directly to attention, memory, learning, executive function and visuospatial function (for all items P < 0.001). Spouse relationship type showed inverse association with memory, learning, executive function and visuospatial function (P < 0.05). Cognitive domains in PD patients may be under the influence of different factors. Due to the lack of control group in this study, cautious interpretation of findings is needed.

Pantothenate kinase associated neurodegeneration (PKAN) is the most prevalent type of neurodegeneration with brain iron accumulation (NBIA) disorders characterized by extrapyramidal signs, and ‘eye-of-the-tiger’ on T2 brain magnetic resonance imaging (MRI) characterized by hypointensity in globus pallidus and a hyperintensity in its core. All PKAN patients have homozygous or compound heterozygous mutation in PANK2 gene. Three sibling patients were diagnosed based on clinical presentations especially extrapyramidal signs and brain MRI. The exons and flanking intronic sequences of PANK2 were sequenced from DNA of leukocytes of the affected individuals. All patients were homozygous for c.C1069T, p.R357W in PANK2 gene. This mutation is well conserved in the homologous protein of distally related spices. In the current study we identified three siblings affected with PKAN, all of them have mutations in PANK2 gene. In MRI of all patients with PANK2 mutation eye-of-the-tiger sign was apparent.