Towards the better understanding about pathogenesis of chronic daily headache.

Evolution of episodic headaches, especially migraine to chronic daily or near-daily headache is an interesting phenomenon. Although its pathogenesis is still unclear the derangement of the brainstem modulatory system is a possible explanation. Recent evidences indicate the involvement of rostral brainstem activation and the attack of migraine. Several nuclei located in this area namely periaquiductal grey, nucleus raphe, locus ceruleus are known to be pivotal in the modulation of sensory information. Therefore, derangement of this complex network can result in abnormal sensory perception, e.g. throbbing headache, photophobia, phonophobia, etc as seen during the attacks of migraine. Chronic alteration of this system can lead to an increase in headache frequency. Evidences from animal experiments indicate that dysfunction of the sensory modulation system in the brainstem also promote the development of central sensitization, a condition in which central nociceptive neurons are more responsive to stimuli. Particular symptoms of chronic daily headache, namely increased headache frequency, expansion of headache area and cutaneous allodynia, imply the sensitization of central nociceptive neurons in the trigeminal pathway. A number of animal experiments have confirmed that chronic analgesic exposure lead to changes in serotonin as well as its receptors in the central nervous system. The plasticity of serotonin-dependent pain control system may accelerate the process of sensitization and results in the development of chronic daily headache secondary to analgesic overuse.

Mutation of the Notch 3 gene in a Thai cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy family.

The authors report the first Thai family with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) in which the family members had a classical history of progressive vascular dementia. The proband was a 31-year old Thai male who presented with an acute stroke in the subcortical region. His past history revealed mental disturbance, including poor judgement and regressive behavior as well as mood changes for 1 year. He did not have a history of migraine or any other vascular risk factors except for a strong family history of ischemic stroke and progressive dementia. Magnetic resonance imaging demonstrated multiple small infarctions in the subcortical white matter of the bilateral frontal, parietal and occipital lobes with another small lesion in the pons. Genetic study demonstrated a Notch 3 mutation consisting of the substitution of a nucleotide at position 406 in exon 3 leading to the replacement of an Arginine by Cysteine at position 110 in the 2nd EGF motif, which is compatable with CADASIL.

Changes of immune system in military recruits after the training program.

The aim of the exercise was to improve body health including the immune system function. However, several studies have observed the suppression of immune response in athletes who were trained with strenuous exercise. Recruits who have been in the recruitment-training program for 8 weeks might also have immune suppression. Twenty males, aged from 21 to 23 years in Chulachomklao Royal Military Academy infantry battalion volunteered to participate in this study. They were asked to wear a Polar Accurex Plus Telemetric heart rate monitor during the training period. Tuberculin skin test which is the screening method for cellular immune responses was significantly decreased at post-training compared to the pre-training (p<0.02). The levels of serum IgG and IgM at pre-training, 4th week, 8th week and one week post-training were significantly decreased at the initiation period, which were compared with pre-training and 4th week of training (p<0.01), and returned to normal at the 8th week of training and one week post-training. The level of circulating immune cells and number of CD markers (CD3, CD4, CD8, and CD56) were not significantly changed throughout the training period. This study demonstrated that subjects who underwent the recruit-training program were able to improve their health after the period of training i.e., in the adaptation period. The decrease in the initiation period could be compensated with proper diet and enough rest.