Neural correlates of auditory feedback control in human.

Auditory feedback plays an important role in natural speech production. We conducted a functional magnetic resonance imaging (fMRI) experiment using a transformed auditory feedback (TAF) method to delineate the neural mechanism for auditory feedback control of pitch. Twelve right-handed subjects were required to vocalize /a/ for 5 s, while hearing their own voice through headphones. In the TAF condition, the pitch of the feedback voice was randomly shifted either up or down from the original pitch two or three times in each trial. The subjects were required to hold the pitch of the feedback voice constant by changing the pitch of original voice. In non-TAF condition, the pitch of the feedback voice was not modulated and the subjects just vocalized /a/ continuously. The contrast between TAF and non-TAF conditions revealed significant activations; the supramarginal gyrus, the prefrontal area, the anterior insula, the superior temporal area and the intraparietal sulcus in the right hemisphere, but only the premotor area in the left hemisphere. This result suggests that auditory feedback control of pitch is mainly supported by the right hemispheric network.

Cerebral activation related to the control of mastication during changes in food hardness.

To investigate the neural network involved in the control of mastication during changes in food hardness, we employed functional magnetic resonance imaging while 15 healthy subjects chewed gum whose hardness was changed by chewing. By comparing the areas activated when the hardness of the bolus varied widely with those seen when the hardness of the bolus had stabilized, we identified selective activations of the supplementary motor area, the dorsolateral prefrontal cortex, the superior temporal gyrus of the left hemisphere, and the premotor area and inferior parietal lobule of the right hemisphere. These findings indicate that these areas are probably related to processes linking sensory input and motor output involved in the change of hardness food during mastication.

Gene expression in the rat brain during sleep deprivation and recovery sleep: an Affymetrix GeneChip study.

Previous studies have demonstrated that macromolecular synthesis in the brain is modulated in association with the occurrence of sleep and wakefulness. Similarly, the spectral composition of electroencephalographic activity that occurs during sleep is dependent on the duration of prior wakefulness. Since this homeostatic relationship between wake and sleep is highly conserved across mammalian species, genes that are truly involved in the electroencephalographic response to sleep deprivation might be expected to be conserved across mammalian species. Therefore, in the rat cerebral cortex, we have studied the effects of sleep deprivation on the expression of immediate early gene and heat shock protein mRNAs previously shown to be upregulated in the mouse brain in sleep deprivation and in recovery sleep after sleep deprivation. We find that the molecular response to sleep deprivation and recovery sleep in the brain is highly conserved between these two mammalian species, at least in terms of expression of immediate early gene and heat shock protein family members. Using Affymetrix Neurobiology U34 GeneChips , we also screened the rat cerebral cortex, basal forebrain, and hypothalamus for other genes whose expression may be modulated by sleep deprivation or recovery sleep. We find that the response of the basal forebrain to sleep deprivation is more similar to that of the cerebral cortex than to the hypothalamus. Together, these results suggest that sleep-dependent changes in gene expression in the cerebral cortex are similar across rodent species and therefore may underlie sleep history-dependent changes in sleep electroencephalographic activity.

Region-specific changes in immediate early gene expression in response to sleep deprivation and recovery sleep in the mouse brain.

Previous studies have documented changes in expression of the immediate early gene (IEG) c-fos and Fos protein in the brain between sleep and wakefulness. Such expression differences implicate changes in transcriptional regulation across behavioral states and suggest that other transcription factors may also be affected. In the current study, we examined the expression of seven fos/jun family member mRNAs (c-fos, fosB, fos related antigen (fra)1, fra-2, junB, c-jun, and junD) and three other IEG mRNAs (egr-1, egr-3, and nur77) in mouse brain following short-term (6 h) sleep deprivation (SD) and 4 h recovery sleep (RS) after SD. Gene expression was quantified in seven brain regions by real-time reverse transcription-polymerase chain reaction (RT-PCR). Multivariate analysis of variance revealed statistically significant variation in cerebral cortex, basal forebrain, thalamus and cerebellum. Levels of c-fos and fosB mRNA were elevated during SD in all four of these brain regions. In the cerebral cortex, junB mRNA was also elevated during SD whereas, in the basal forebrain, fra-1 and fra-2 mRNA levels increased in this condition. During RS, the only IEG mRNA to undergo significant increase was fra-2 in the cortex. C-jun and junD mRNAs were invariant across experimental conditions. These results indicate that the expression of fos/jun family members is diverse during SD. Among other IEGs, nur77 mRNA expression across conditions was similar to c-fos and fosB, egr-1 mRNA was elevated during SD in the cortex and basal forebrain, and egr-3 mRNA was elevated in the cortex during both SD and RS. The similarity of fosB and nur77 expression to c-fos expression indicates that these genes might also be useful markers of functional activity. Along with our previous results, the increased levels of fra-2 and egr-3 mRNAs during RS reported here suggest that increased mRNA expression during sleep is rare and may be anatomically restricted.

Differential increase in the expression of heat shock protein family members during sleep deprivation and during sleep.

Although sleep is thought to be restorative from prior wakeful activities, it is not clear what is being restored. To determine whether the synthesis of macromolecules is increased in the cerebral cortex during sleep, we subjected C57BL/6 mice to 6 hours of sleep deprivation and then screened the expression of 1176 genes of known function by using cDNA arrays. The expression of the heat shock proteins (HSP), endoplasmic reticulum protein (ERp72) and glucose-regulated protein (GRp78), was among the genes whose expression was significantly elevated in the cortex during sleep deprivation, whereas GRp78 and GRp94 mRNAs were elevated in the cortex during recovery sleep after sleep deprivation, as confirmed by conventional and quantitative real-time polymerase chain reaction and/or Northern analyses. A systematic evaluation of the expression of six heat shock protein family members (ERP72, GRp78, GRp94, HSP27, HSP70-1, and HSP84) in seven brain regions revealed increased mRNA levels in cortex, basal forebrain, hypothalamus, cerebellum and medulla during sleep deprivation, whereas increased mRNA levels during recovery sleep were limited to the cortex and medulla. Immunohistochemical studies identified increased numbers of GRp78-, GRp94-, and ERp72-immunoreactive cells in the dorsal and lateral cortex during sleep deprivation but, during recovery sleep, elevated numbers of these cells were found only in the lateral cortex. In the medulla, increased numbers of GRp94-immunoreactive cells were observed in nucleus tractus solitarius, dorsal motor nucleus of the vagus and the rostroventrolateral medulla during recovery sleep. The widespread increase of heat shock protein family mRNAs in brain during sleep deprivation may be a neuroprotective response to prolonged wakefulness. In contrast, the relatively limited heat shock protein family mRNA expression during recovery sleep may be related to the role of heat shock proteins in protein biogenesis and thus to the restorative function of sleep.

Transcriptional regulation of the mouse fatty acid amide hydrolase gene.

Fatty acid amide hydrolase (FAAH) is a membrane-bound enzyme that inactivates a family of fatty acid amide molecules which are implicated in physiological processes such as pain and sleep. We cloned a 1.9 kb fragment of the 5'-untranslated region of the mouse FAAH gene into the pGL3 basic luciferase reporter vector and showed that this sequence has promoter activity in vitro. By primer extension analysis, we have determined the transcription start site to be 200 bases upstream of the ATG initiation codon and found that a TATA motif was absent. A number of putative response elements, including those for estrogen and glucocorticoids, were identified in this sequence. We have demonstrated that the estrogen and glucocorticoid receptors down-regulate transcriptional activity independent of their ligand. These data should help in understanding the mechanisms of FAAH gene transcription.

Modulation of the promoter region of prepro-hypocretin by alpha-interferon.

Hypocretins 1 and 2 (also called orexins A and B, respectively) are hypothalamic neuropeptides that have recently been shown to be involved in the sleep disorder narcolepsy and possibly in the normal regulation of sleep and wake functions. These two peptides are derived from a single precursor molecule called prepro-hypocretin, also known as prepro-orexin. We have cloned a 450 bp fragment from the 5'-flanking region of the human prepro-hypocretin gene and demonstrated that this fragment has promoter activity in vitro. Deletions at the 5' end from -450 to -188 reduced the promoter activity by approximately 50%. Further deletion from the 5'-end to -69 almost completely abolished promoter activity. The 450 bp fragment contains a number of potential transcription factor binding sites, including an interferon (IFN) response element. Our studies demonstrate that alpha-IFN strongly inhibits the promoter activity of both 450 and 188 bp fragments in a dose-dependent manner. The inhibitory effect of alpha-IFN is consistent with recent studies which suggest that hypocretin 1/orexin A may be involved in modulating arousal states and with the literature indicating involvement of immune-related molecules in sleep regulation.

Prepro-hypocretin (prepro-orexin) expression is unaffected by short-term sleep deprivation in rats and mice.

The hypocretin/orexin ligand-receptor system has recently been implicated in the sleep disorder narcolepsy. During the dark (active) period, null mutants of the prepro-orexin (prepro-hypocretin) gene have cataplectic attacks and increased levels of both rapid eye movement (REM) and non-REM (NREM) sleep. Intracerebroventricular injection of one of the encoded neuropeptides, orexin-A, early in the light period increases wakefulness and reduces REM sleep in the rat, suggesting that this system may be involved in the normal regulation of sleep and wakefulness. To further test this hypothesis, we measured hypocretin (hcrt) mRNA levels by both Northern hybridization and Taqman analysis in mouse and rat hypothalamus after short-term (6 h) sleep deprivation (SD) and 2-4 hours after recovery from SD. Although our SD procedures effectively induced a sleep debt and increased c-fos mRNA expression in the cortex and hypothalamus as described by other investigators, we found that hcrt mRNA levels were not significantly changed in either species either after SD or after recovery from SD. If the hcrt system is involved in normal regulation of sleep and wakefulness, longer periods of SD may be necessary to affect hcrt mRNA levels or changes may occur at the protein rather than mRNA level. Alternatively, this system may also be involved in another function that counterbalances any SD-induced changes in hcrt mRNA levels.

An elevation of serum immunoglobulin E provides a new aspect of hyperthyroid Graves' disease.

In hyperthyroid Graves' disease, short-term methimazole is sufficient to induce lasting remission in some patients, but even long-term treatment fails to do so in others. We have evaluated the role of autoimmune abnormalities in the helper T cell type 2 (TH2)-interleukin-13 (IL-13)-TSH receptor system in maintaining hyperthyroidism by comparing IgE levels in patients with various thyroid diseases. One hundred and ninety-three patients with hyperthyroid Graves' disease were treated with methimazole, and blood samples were obtained to measure serum levels of T4, T3, TSH, thyroglobulin, antimicrosomal antibody, TSH binding inhibitory Ig (TBII), thyroid-stimulating antibody, thyroid stimulation-blocking antibody, IgE, interferon-gamma, IL-4, and IL-13. Elevation of serum IgE (> or = 170 U/mL) was found in 35.5% of patients with hyperthyroid Graves' disease, and serum levels of T4, T:1, antimicrosomal antibody, and TBII were significantly greater in patients with IgE elevation than in those with normal serum IgE. During methimazole treatment, there was a parallel decrease in the serum T4 concentration in the presence or absence of an IgE elevation. However, there was a significantly smaller decrease in TBII in patients with elevated IgE than in those with normal IgE. As a result, the remission rate was significantly greater in patients with normal IgE than in those with IgE elevation. Serum levels of IL-13 were elevated in 64.7% of patients with IgE elevation in the absence of detectable TH1 marker, interferon-gamma. These findings suggest that in one third of patients with hyperthyroid Graves' disease, TH2 cells are stimulated and secrete excess amounts of IL-13, which subsequently stimulates B cells to synthesize more TSH receptor antibody and IgE, so that during methimazole treatment TBII decreases less in patients with IgE elevation, producing a lower remission rate.

Importance of hypercoagulability over hyperglycemia for vascular complication in type 2 diabetes.

To critically evaluate the relative importance of coagulation abnormalities over other clinical variables for micro- and macrovascular diabetic complications, prothrombin fragment (F1+2), thrombin-antithrombin III complex (TAT), fibrin degradation product d-dimer, and alpha2 plasmin inhibitor complex were determined in 101 stable, relatively well controlled patients with Type 2 diabetes (the mean HbA1c, age and duration of diabetes, 7.1%, 61 and 7.5 years, respectively). First, incidence and severity of diabetic micro- and macroangiopathies were progressively increased with the severity of coagulation abnormalities. Next, correlation of the four values with the presence of micro- and macrovascular complications, respectively, was analyzed by the multiple logistic regression analysis, with the inclusion of other variables such as age, duration of diabetes, HbA1c, blood pressure, and urinary albumin excretion. With the presence of microangiopathies, F1+2 and systolic blood pressure were significantly related, with the relationship being very strong for the former (P=0.003) and weak for the latter (P=0.035). On the other hand, with the presence of macroangiopathies, F1+2 (P=0.003), TAT (P=0.002), duration of diabetes (P=0.015), and age (P=0.013) were related. Other clinical variables were not significantly related with the presence of complications. Coagulation and fibrinolytic abnormalities are stronger determinants of the presence of diabetic vascular complications than other clinical variables including the degree of glycemia, in stable, relatively well controlled patients with Type 2 diabetes.

Cyclooxygenase in the vagal afferents: is it involved in the brain prostaglandin response evoked by lipopolysaccharide?

The vagal afferents are proposed to transmit abdominal immune signals to the brain. In this immune-brain communication, prostaglandins might play a mediator role. In fact, prostaglandin receptors are abundant in the vagal afferents. We examined here the presence of cyclooxygenase, an enzyme necessary for prostaglandin biosynthesis, in the vagal afferents of rats. We also tested whether the vagal afferents contribute to the elevation of prostaglandin E2 in the brain after intraperitoneal injection of lipopolysaccharide. Under normal conditions, cyclooxygenase-1-like immunoreactivity was constitutively expressed in the vagal afferents at their central terminals and in their cell bodies. Cyclooxygenase-2-like immunoreactivity was absent in the vagal afferents under normal as well as lipopolysaccharide-challenged conditions. Instead, cyclooxygenase-2-like immunoreactivity was induced in brain endothelial cells by the lipopolysaccharide challenge. The elevation of prostaglandin E2 in the cerebrospinal fluid after lipopolysaccharide challenge was not inhibited, but was rather enhanced, by the bilateral vagotomy. These results suggest that the vagal afferents potentially generate prostaglandins, which may locally modulate the vagal signal transmission, but that the vagal afferents are not essential to the elevation of prostaglandin E2 in the brain after intraperitoneal challenge with LPS.

Comparison of the prevalence of asymptomatic carotid atherosclerosis detected by high-resolution ultrasonography in rural and urban middle-aged Japanese men.

BACKGROUND AND PURPOSE: We have recently shown that extracranial carotid atherosclerosis is not uncommon in urban regions of Japan. Rural data have, however, been scarcely reported. The aim of this study was to investigate the prevalence of asymptomatic extracranial carotid lesions in rural populations compared with urban populations. METHODS: The subjects in the rural region consisted of 249 men, aged 50 to 69 years. Urban subjects were 610 men of the same age range. Carotid ultrasound examinations were performed with 7.5-MHz high-resolution ultrasonography. RESULTS: Detection of severe atherosclerosis (stenosis of 50%) was significantly higher (P<.05) in rural subjects (9.6%) than in urban subjects (4.6%). Multiple regression analysis of carotid atherosclerosis showed significant relationships with age, fasting blood glucose, hypertension, pack-years of smoking, total serum cholesterol, and high-density lipoprotein cholesterol for the rural subjects as well as for the urban subjects (P<.05). CONCLUSION: The present cross-sectional study showed that, in middle-aged men, the prevalence of severe carotid atherosclerosis was higher in rural populations compared with urban populations of Japan. This was attributed to long-term exposure to hypertension.

[A case of zoster sine herpete with involvement of the unilateral IX, X and XI cranial and upper cervical nerves].

We describe a case of unilateral IX, X and XI cranial and upper cervical nerve palsies involving zoster sine herpete (ZSH). A 63-year-old man experienced nausea, loss of appetite and general fatigue. On 4 days of illness, dysphagia, dysarthria and difficulty in elevation of his right arm appeared. Neurological examination showed the right curtain sign, a nasal voice and a decreased right gag reflex. He could hardly elevate his right arm laterally. Needle electromyography revealed positive sharp waves in his right trapezius muscle. Although no skin lesion was detected, anti-varicella-zoster virus antibodies were positive in both serum and cerebrospinal fluid. Acyclovir and a steroid were ineffective for these symptoms. Although case reports of unilateral IX, X and XI cranial nerve palsies with ZSH is very rare, ZSH should be kept in mind in the differential diagnosis of multiple cranial nerve palsies.

A possible role of immunoglobulin E in patients with hyperthyroid Graves' disease.

To investigate the possible participation of immunoglobulin E (IgE) in the autoimmune process of Graves' disease, incidence of elevation of serum IgE level, TSH receptor antibody (TRAb), and thyroid status were studied in 66 patients with hyperthyroid Graves' disease, 54 patients with Hashimoto's thyroiditis, 19 patients with bronchial asthma, and 15 patients with pollen allergy. In hyperthyroid Graves' patients, elevation of serum IgE levels (> or = 170 U/mL) was found in 19 of 66 patients (29%), 11 of whom had hereditary and/or allergic conditions. Elevations of serum IgE levels were found in 63% of patients with bronchial asthma and in 40% of patients with pollen allergy. Mean values of serum IgE were the same in patients with hyperthyroid Graves' disease and with bronchial asthma. During methimazole treatment TRAb decreased without fluctuation of IgE levels in both groups. The decrease in TRAb was significantly greater in patients with normal IgE than in patients with IgE elevation. After prednisone administration, reduction in TRAb was greater in patients with normal IgE than that in patients with IgE elevation. High incidence of IgE elevation in hyperthyroid Graves' disease and slower reduction in TRAb in association with IgE elevation suggest a difference in the autoimmune processes in Graves' disease with and without elevation of IgE.

[A survey of smoking behavior among junior high school students and smoking prevention education developed using the survey results].

In June 1996 and 1997, a self-administered anonymous questionnaire survey of smoking behavior was conducted on students (118 boys and 135 girls) of two junior high schools in Kami-gun, Kochi Prefecture. Following the surveys, smoking prevention education classes were held using the survey results as material for education. The survey results were as follows; 1. The percentage of ever-smokers was higher in boys than in girls, 37.9% and 22.8% respectively. The percentage of those who smoked at least one cigarette during the past one month was 2.9%, and the rate increased with school grade. 2. Most commonly, first experience of smoking was between the 4th to 6th grades in elementary school, and the main motive for first smoking was curiosity. 3. The association between smoking and lung cancer was the most widely known, and that between smoking and intrauterine growth retardation was relatively well-known among students. More than 90% of students clearly understood the harmfulness of passive smoking. 4. The results of logistic regression analyses revealed that friends' and parents' smoking were significant correlates of smoking experience in boys. Among girls no significant relationship was found. The content of smoking prevention education class consisted of quizzes about smoking, an explanation of the survey results, an exhibition of a cross-sectional model of the lung, an experiment of smoking using a small doll, an analysis of expired air carbon monoxide concentration, and an explanation of the harmfulness of smoking. The reports of the students after the class showed that not only the explanation of the harmfulness of smoking, but also the experiment or explanation of the survey results appeared to be effective educational content.

[Factors relate to participation in medical checkups in a rural community an analysis including social network scores].

Since 1969, community-based stroke prevention programs have been conducted in N town, Kochi prefecture. To clarify factors related to participation in medical checkups including social networks, a cross-sectional questionnaire survey was performed on 6,704 residents aged 40 and over in N town in 1996. 1. Location of the workplace, types of medical insurance and interest in health were significantly associated with participation in medical checkups. 2. Participation in medical examinations provided at the workplace was significantly, inversely related with participation rates in community checkups in the group aged 40 to 59 years. 3. Low independence level in daily activities was inversely associated with participation rates for medical checkups in groups aged 60 years and older. 4. Visiting medical facilities was inversely associated with the participation rate for medical checkups in female groups. 5. The group with the highest social networks score (5 points) had the highest participation rate for medical checkups. After adjusting for other participation related factors, social networks scores had a significantly positive association with the participation rate for medical checkups provided by the Health Services for the Elderly Act.

Localization of a gene for benign adult familial myoclonic epilepsy to chromosome 8q23.3-q24.1.

Benign adult familial myoclonic epilepsy is an autosomal dominant idiopathic epileptic syndrome characterized by adult-onset tremulous finger movement, myoclonus, epileptic seizures, and nonprogressive course. It was recently recognized in Japanese families. In this study, we report that the gene locus is assigned to the distal long arm of chromosome 8, by linkage analysis in a large Japanese kindred with a maximum two-point LOD score of 4.31 for D8S555 at recombination fraction of 0 (maximum multipoint LOD score of 5.42 for the interval between D8S555 and D8S1779). Analyses of recombinations place the locus within an 8-cM interval, between D8S1784 and D8S1694, in which three markers, D8S1830, D8S555, and D8S1779, show no recombination with the phenotypes. Although three other epilepsy-related loci on chromosome 8q have been recognized-one on chromosome 8q13-21 (familial febrile convulsion) and two others on chromosome 8q24 (KCNQ3 and childhood absence epilepsy)-the locus assigned here is distinct from these three epilepsy-related loci. This study establishes the presence of a new epilepsy-related locus on 8q23.3-q24.11.

Plasma level of homocysteine is correlated to extracranial carotid-artery atherosclerosis in non-hypertensive Japanese.

BACKGROUND: Results of some epidemiologic studies in Western countries have clarified that hyperhomocysteinemia is a plausible risk factor for atherosclerotic vascular disease, but its role in Japanese communities is not known. DESIGN: A community-based cross-sectional design. METHODS: We performed a cross-sectional study of 474 elderly men aged 60-74 years in two Japanese rural communities (Noichi in southwestern Japan and Ikawa in northeastern Japan). We examined the association between plasma concentrations of homocysteine and the maximum intima-media thickness (assessed by ultrasonography). RESULTS: The prevalence of thickening was 10.7% for the lowest tertile of homocysteine level and 21.1% for the highest tertile. For the subjects without hypertension, the odds ratio for having carotid intima-media thickening was 5.8; it was significantly higher for the highest tertile of homocysteine level than it was for the lowest after adjusting for age, hypercholesterolemia, hypoalphalipoproteinemia, diabetes, and smoking by using a multiple logistic regression model. However, its correlation was not evident for those with hypertension. CONCLUSIONS: High levels of plasma homocysteine are correlated to extracranial carotid artery atherosclerosis in elderly men without hypertension in Japanese rural communities.