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Notes: The purpose of the present study was to elucidate the effects of unilateral masseter muscle pain on the jaw-jerk reflex. The latency and peak-to-peak amplitude of bilateral electromyographic activity recorded at the masseter muscles during the jaw-jerk reflex were measured in 18 patients with craniomandibular dysfunction (CMD) with strictly unilateral masseter pain or tenderness and 10 control subjects using a computerized recording and analysis system. The reflex was elicited, at the mandibular rest position, by tapping the centre of the chin downwards with a reflex hammer incorporating a microswitch that triggered the sweep of the recording apparatus upon contact with the chin. In the CMD group, the jaw-jerk latency on the affected side (6·89±0·98 ms) was significantly shorter (P〈0·01) than that on the unaffected side (7·59±0·92 ms). In the control group, there was no difference between the jaw-jerk latencies on the right (7·06±0·64 ms) and the left (7·08±0·65 ms) sides. The range of side asymmetry for jaw-jerk latencies in the CMD group was greater than that in the control group. In six patients, the latency difference exceeded 1 ms. The asymmetry of latency of the jaw-jerk reflex was thought to be due to facilitation on the side with masseter pain or tenderness. This facilitation on the ipsilateral side might be produced by enhanced gamma drive induced by sustained nociceptive stimulation. Such effects may be related with clinically derived concepts regarding such muscle dysfunction as myospastic activity or trigger points.

Notes: Summary Darier's disease is an autosomal dominant skin disorder that is characterized by multiple keratotic papules, focal loss of adhesion and abnormal keratinization. Mutations in the ATP2A2 gene encoding sarco/endoplasmic reticulum calcium pumping ATPase type 2 have been identified as the molecular basis of Darier's disease. Segmental Darier's disease is a rare type of Darier's disease in which there is characteristic localization of the keratotic papules in a linear pattern following Blaschko's lines. In this study we examined ATP2A2 mutations in a Japanese patient with segmental Darier's disease. The samples from affected skin, unaffected skin and peripheral leucocytes were subjected to polymerase chain reaction (PCR). Direct sequencing of the PCR products was performed. Sequence analysis revealed that the patient had 160A→G substitution mutation which predicts I54V. This novel mutation was present in the affected skin, but not in the unaffected skin or peripheral leucocytes. This is the first report of segmental Darier's disease caused by mosaicism for an ATP2A2 mutation in Japan.

Notes: Summary Exercise-induced anaphylaxis (EIA) is a form of physical urticaria that is induced by exercise. A 16-year-old Japanese boy had a 4-year history of recurrent wealing and dyspnoea after physical exercise such as jogging, playing handball or riding a bicycle in winter. The episodes were not associated with ingestion of foods including wheat or soya bean. A provocation test, with 15 min of exercise and 2 min of cold stimulation immediately before or immediately after the exercise, elicited a weal that was localized to the test area. A challenge test with ingestion of boiled soya beans and exercise did not elicit a weal. Therefore, in this case, cold exposure, but not food ingestion, was essential for inducing EIA. Cold-dependent EIA is different from cold urticaria, food-dependent EIA, cholinergic urticaria and cold-induced cholinergic urticaria, and may be a distinct entity.

Notes: Human epidermal cells were cultured with pemphigus antibody in the presence of hydrocortisone, methlprednisolone sodium succinate, dapsone and gold. Hydrocortisone and methylprednisolone reduced the production of the enzyme plasminogen activator but dapsone and gold had no effect. These results support the hypothesis that corticosteroids have dual effects on pemphigus through inhibition of plasminogen activator production by epidermal cells and suppression of pemphigus antibody production by B lymphocytes.

Notes: The molecular sizes of secreted and cell-associated plasminogen activators from four cultured cell types were determined using an SDS-PAGE technique in which plasminogen and casein were included during polymerization of the polyacrylamide gel. The major bands of plasminogen activators secreted by human neonatal epidermal cells, human adult epidermal cells and transformed human squamous cells migrated the same distance as the high molecular weight band of authentic urokinase, indicating that the apparent molecular weight of these plasminogen activators was approximately 55,000 daltons. Plasminogen activator extracted from normal adult human epidertnis also migrated with this major band of plasminogen activator, and a minor higher molecular weight band was also detected. In contrast, plasminogen activators secreted by transformed mouse squamous cells migrated between the high molecular weight band (∼ 55K) and the low molecular weight band of urokinase (∼ 32K), indicating that plasminogen activators of mouse epidermal cells differ from those of human epidermal cells. The mobility of the major bands of plasminogen activators detected in cell lysates of the four cell types was identical to that of secreted plasminogen activators.

Notes: In our previous study, apparent reduction of glucocorticoid receptor (GR) mRNA was seen in the hippocampus and the hypothalamic paraventricular nucleus (PVN) during repeated immobilization (IMO) stress, but not following starvation. Our laboratory has also shown that the sp1 activates, whereas tumour suppressor p53 represses the promoter activity of GR gene. In an attempt to reveal the possibility that transcription factors such as sp1 and/or p53 are involved in the regulation of GR mRNA expression in the hippocampus and in the PVN in vivo, we examined the expression of GR mRNA, p53 mRNA, and sp1 mRNA in the hippocampus and in the PVN during repeated IMO and following starvation. In addition, the expression of these mRNAs was examined in the anterior pituitary, another GR-rich area. GR mRNA in all subfields of the hippocampus was robustly decreased, while GR mRNA in the anterior pituitary was increased, 24 h following 4 × IMO (2 h daily, for 4 consecutive days) and immediately after 5 × IMO. GR mRNA in the PVN was significantly decreased immediately after 5 × IMO, but not at 24 h after 4 × IMO. Conversely, p53 mRNA in the PVN and hippocampus was increased, whereas p53 mRNA in the anterior pituitary was decreased, 24 h following 4 × IMO and immediately after 5 × IMO. Sp1 mRNA was unchanged in all areas examined following repeated IMO. Following 4 days of starvation, neither GR mRNA, p53 mRNA nor sp1 mRNA showed any changes in the PVN and the hippocampus, except there was a minor decrease in GR mRNA in CA1-2. In the anterior pituitary, 4 days of starvation induced a minor, but significant increase in GR mRNA, whereas it decreased p53 mRNA. Overall, regression analyses revealed a negative correlation between GR mRNA levels and p53 mRNA levels in CA1-2 and dentate gyrus of the hippocampus and in the anterior pituitary. GR mRNA in the PVN also showed a tendency towards the negative correlation with p53 mRNA levels. The results raise the possibility that p53 negatively regulates GR mRNA expression in the PVN, the hippocampus and the anterior pituitary during repeated immobilization stress.

Notes: During starvation, counterregulatory responses to loss of food (i.e. responses that lead to an increase in appetite) occur in the central nervous system (CNS). This study was designed to examine whether middle-aged rats show greater or smaller behavioural, peripheral and central hormonal responses during starvation compared to young rats. In experiment 1, refeeding following 4 days of starvation was measured in both middle-aged (72-week-old) and young (9-week-old) rats. The level of refeeding was similar to each prestarved level until 3 days after the end of starvation in both groups. From the 4th day, the level of refeeding in young rats increased and reached beyond the prestarved level, whereas refeeding in middle-aged rats remained similar to the prestarved level. Thus, overall refeeding throughout 7 days was greater in young rats than in middle-aged rats. In experiment 2, middle-aged and young rats were starved for 4 days and were killed in the morning. Middle-aged rats showed a smaller plasma corticosterone response than that of young rats. The magnitude of decreases in plasma glucose, insulin and leptin was similar in both groups. In the arcuate nucleus, the starvation-induced increase in neuropeptide Y (NPY) mRNA and the decrease in proopiomelanocortin (POMC) mRNA were smaller in middle-aged rats than in young rats. In contrast, the starvation-induced decrease in corticotrophin-releasing hormone (CRH) mRNA in the hypothalamic paraventricular nucleus was greater in middle-aged rats than young rats. The magnitude of decrease in type-2 CRH receptor mRNA in the ventromedial hypothalamus was similar in both groups. The results indicate that (a) ageing impaired refeeding response (b), middle-aged rats showed the same directional neuropeptide mRNA responses as seen in young rats during starvation and (c) the magnitude of these counterregulatory responses in the CNS in middle-aged versus young rats was not uniform, but rather was site-specific or neuropeptide-specific. This study suggests the importance of NPY and POMC responsiveness in the arcuate nucleus in the age-related differences resulting from starvation-induced refeeding.