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Biomedical subjects

Shigeru Watanabe

Publications and source records attributed to Shigeru Watanabe.

At least 37 records · Page 2Linked to original sources
PubMed2005

Aconiti tuber increases plasma nitrite and nitrate levels in humans.

Some herbal medicines, including Aconiti tuber (Aconitum carmichaeli Debeaux, Ranunculaceae), have been recognized as being effective for the treatment of a "peripheral uncomfortable feeling of cold (hie)". We hypothesized that these compounds affect peripheral vascular function via the nitric oxide (NO) system, which leads to recovery from "hie". To answer this question, we investigated Aconiti tuber-induced changes in plasma levels of nitrite (p-NO2-) and nitrate (p-NO3-), final nitric oxide-oxidation products measurable in vivo. After written informed consent was obtained, patients suffering from "hie" were treated with several kinds of kampo (Japanese traditional herbal medicine), selected on the basis of traditional theory. Twenty-four patients took kampo formulas, some included Aconiti tuber (n=11; A-group) and others did not (n=13; C-group), for 4 weeks. p-NO2- and p-NO3- levels were measured before the start and after 4 weeks of treatment. In the A-group, the p-NO2- plus p-NO3- (p-NOx) level was significantly increased at 4 weeks (p=0.04), while that of the C-group was not. There was a statistically significant increase in the p-NOx level of the A-group as compared to the C-group (d.f.=1,22, F=9.38, p=0.006). The results suggest that Aconiti tuber may increase NO production in humans.

Aconitum↗
PubMed2005

Effects of intraperitoneal administration of IFN-alpha for one, four, and fourteen days on amino acid levels in various rat brain regions.

Interferon-alpha (IFN-alpha) therapy is strongly associated with certain adverse effects, but the pathophysiologic mechanism is unclear. The present study was designed to investigate the influence of peripherally administered IFN- alpha on amino acid levels in the brain. IFN-alpha was administered intraperitoneally (i.p.) once daily to rats, and their brains were extracted 24 h after the last injection. The levels of glutamate, glycine, taurine, gamma-aminobutyric acid (GABA), and arginine in homogenized samples of the frontal cortex, striatum, hippocampus, amygdala, thalamus, hypothalamus, cerebellum, and brainstem were determined. One day of IFN-alpha treatment induced no significant changes in any of these amino acids. After 4 days of injections, glutamate, glycine, taurine, and gamma-aminobutyric acid levels were significantly higher than those in the control frontal cortex, striatum, hippocampus, amygdala, and thalamus. However, most of these amino acids returned to approximately basal levels, or even lower, with 14-day treatment. Our results suggest that daily peripheral administration of IFN-alpha affects the metabolism of amino acids in the brain. Further studies are necessary to determine if these effects of IFN-alpha on cerebral amino acids are involved in the pathophysiology of IFN-alpha-induced depression.

Amino Acids↗
PubMed2005

Effects of intraperitoneally injected lithium, imipramine and diazepam on nitrate levels in rat amygdala.

Nitric oxide (NO) has been studied in relation to the etiologies of various neurologic and psychiatric diseases. However, little is known about whether clinically available psychotropic drugs affect the NO system in the brain. Using an in vivo brain microdialysis method, the effects of intraperitoneally administered lithium, imipramine and diazepam on levels of , a marker of in vivo NO production, were investigated in the rat amygdala. Lithium significantly reduced, while imipramine raised, levels as compared with controls. These observations suggest that lithium and imipramine induce opposite effects on NO-related systems in the brain.

Amygdala↗
PubMed2004

Spatial learning deficits after the development of dorsomedial telencephalon lesions in goldfish.

The effects of lesions in the dorsal area of the caudal telencephalon (Carassius auratus) on the retention of spatial learning in goldfish were examined. The experimental paradigm was similar to the dry version of the Morris water maze for rodents. After being trained to reach a criterion, goldfish underwent surgery and were then retrained. In the retraining, dorsomedial lesions resulted in poor performance, while dorsolateral lesions did not. In a landmark task in which a small circular colored cue was set at a food location, dorsomedial lesions did not produce impairment during retraining. These results suggest that dorsomedial lesions selectively caused impairment in the retention of spatial learning.

Analysis of Variance↗
PubMed2004

Effects of hippocampal lesions on acquisition and retention of spatial learning in zebra finches.

We tested the role of the hippocampus in spatial memory of zebra finches. The birds were trained to find the location of a food site among four identical feeders arranged on the aviary floor. Extra-maze cues were present. The birds had to perform the task from four different starting points. Successful visits and the time to find the food were recorded. Hippocampal lesions made before acquisition led to a decrease in correct choices. Hippocampal lesions following training disrupted the retention of the spatial memory. Surprisingly, birds with hippocampal damage reached the food as quickly as intact birds, but they needed more visits to find the correct feeder. Therefore, the birds with hippocampal damage used an alternative, nonspatial memory-based strategy to find the food.

Analysis of Variance↗
PubMed2004

Coronary artery calcification detected by a mobile helical computed tomography unit and future cardiovascular death: 4-year follow-up of 6120 asymptomatic Japanese.

In the present study, we performed a prospective follow-up study in a population which underwent chest computed tomography (CT) screening. A total of 6120 participants underwent a chest CT medical examination for lung cancer and tuberculosis in Nagano Prefecture, Japan, between 1996 and 1997. Computed tomography scanning was performed from the apex of the lung to the diaphragm at a tube voltage of 120 kV and a tube current of 50 mA. We measured the CT density of the coronary arteries in 5-7 slices where coronary arteries were detected. The CT density threshold for determining coronary artery calcification (CAC) was above +110 HU. In 2000, we investigated the number of deaths due to cardiac and noncardiac disease among the participants. Of the 6120 participants, 14 died of cardiac disease (9, myocardial infarction; 4, heart failure; and 1, angina pectoris) and 64 died of other diseases. Coronary artery calcification was detected in 10 of the patients who died of cardiac disease, and in 31 of those who died of other diseases. The prevalence of CAC was higher in the former than in the latter (71.4% vs 48.4%, P = 0.084). The relative risk of CAC for cardiac death was 2.66 (95% confidence interval: 0.76, 9.37). The findings of this study suggested that CAC detected in a mass chest CT screening by a mobile helical CT unit was predictive of future cardiovascular death.

Calcinosis↗
PubMed2004

Effects of telencephalic ablation on shoaling behavior in goldfish.

The role of the telencephalon in the shoaling behavior of the goldfish, Carassius auratus, was investigated. Experiments were carried out in a tank divided into three compartments. Subjects were introduced into the center compartment of the tank. In the activity phase, subjects swam alone, and swimming distance was used as an index of activity. In the shoaling behavior phase, a stimulus fish was introduced into one of the side compartments, and the time spent near the side compartment by the subject was used as index of shoaling behavior. After these measurements were made, visual and motor abilities were examined using the optomotor response. Subjects then received surgery and the same procedure was repeated. In Experiment 1, the effects of total ablation of the telencephalon and a section of the olfactory tract (OlT) were examined. The ablation group exhibited reduced activity and shoaling behavior compared with the sham and OlT group. In Experiment 2, the role of the dorsal part of the telencephalon was examined after damaging the dorsomedial and dorsolateral telencephalon. Lesions in either portion had no effect and no simple visual or motor deficits were seen. These results suggest that the ventral part of the telencephalon mediates shoaling behavior.

Animals↗
PubMed2004

Aortic calcification detected in a mass chest screening program using a mobile helical computed tomography unit. Relationship to risk factors and coronary artery disease.

BACKGROUND: There is a significant relationship between calcification of the aortic arch (Arch) detected by chest X-ray examination and coronary artery disease (CAD), but the relationship between risk factors, CAD and aortic calcification detected during a mass screening program using a mobile helical computed tomography (CT) unit remains unknown. METHODS AND RESULTS: In total 2,623 subjects (1,347 men, and 1,276 women; mean age, 52.9+/-13.8) underwent an examination for lung cancer and tuberculosis using a mobile helical CT unit. The frequency of calcification was 19.6% in the Arch, 2.7% in the ascending aorta, and 10.1% in the descending aorta, values that were positively associated with age in both genders. Hypertension and smoking were significantly related to calcification of the thoracic aorta. There was a significant relationship between CAD and aortic calcification. The odds ratio of aortic calcification for patients with CAD increased as the number of calcified segments increased. CONCLUSIONS: These results suggest that detection of calcification in the thoracic aorta during a mass chest screening using a mobile helical CT unit can be used to evaluate the risk of CAD.

Adolescent↗
PubMed2004

Polymorphism of dopamine receptor D4 exon I corresponding region in chicken.

In stockbreeding, there are indications that behavioral traits of livestock have an effect on breeding and production. If the variation in individual behavior is related to that in neurotransmitter-related genes such as in humans, it would be possible to breed pedigrees composed of individuals having behavioral traits that are useful to production and breeding using selection based on genotypes. In this study, we investigated the exon I region of dopamine receptor D4 (DRD4), in which variation is related to psychiatric disorder in humans, in major poultry species namely Japanese quail (Coturnix japonica), chicken (Gallus gallus), ring-necked pheasant (Phasianus colchicus) and helmeted guinea fowl (Numida meleagris). Furthermore, we investigated Japanese cormorant (Phalacrocorax capillatus) and Japanese jungle crow (Corvus macrorhynchos) as an out-group. In these species of birds, the repeat of proline was identified in the region corresponding to the human polymorphic region. The repeat number was 9 in Japanese quail, ring-necked pheasant and Japanese cormorant; 12 in helmeted guinea fowl; and 3 in Japanese jungle crow. However, no polymorphism was found in these species. In contrast, polymorphism was observed in chicken and two alleles with 8 and 9 repeats were identified. Although 9 repeats (allele 9) were predominant in most chicken breeds, Black Minorca had only 8 repeats (allele 8). Intra-breed polymorphism was found in 6 out of 12 breeds, and two alleles (alleles 8 and 9) were detected in these breeds. This polymorphism, which is the first to be reported on a neurotransmitter-related gene in birds, would contribute significant information for elucidation of differences in behavioral traits in chicken breeds.

Amino Acid Sequence↗
PubMed2003

Visual discrimination of normal and drug induced behavior in quails (Coturnix coturnix japonica).

The ability to discriminate the physical states of others could be an adaptive behavior, especially for social animals. For example, the ability to discriminate illness behavior would be helpful for avoiding spoiled foods. We report on an experiment with Japanese quails testing whether these birds can discriminate the physical states of conspecifics. The quails were trained to discriminate between moving video images of quails injected with psychoactive drugs and those in a normal (not injected) condition. Methamphetamine (stimulant) or ketamine (anesthetic) were used to produce drug-induced behaviors in conspecifics. The former induced hyperactive behavior and the latter hypoactive behavior. The subject quails could learn the discrimination and showed generalization to novel images of the drug-induced behaviors. They did not, however, show discriminative behavior according to the type and dosage of the drugs. Thus, they categorized the behavior not on the basis of degree of activity, but on the basis of abnormality.

Animals↗
PubMed2003

IMHV lesions caused deficits in conspecific discrimination in chicks but not in adult quail.

An experiment was conducted to investigate whether there is a functional difference in IMHV between chicks and adults using the conditioned individual preference (CIP) method, a modified conditioned place preference paradigm. CIP training of the quail involved 8 days of alternate injections of morphine or saline followed by associations with a stimulus quail in one compartment of the preference box. After the CIP training, the subject quail were given a choice between the morphine-associated and the saline-associated stimulus quail. All adult and chicks with neostriatum lesion showed a preference for the morphine-associated stimulus quail. However, the chicks receiving bilateral IMHV lesions before CIP did not show any preference for either stimulus quail. These results suggest that there is a functional difference in IMHV between chicks and adults.

Aging↗
PubMed2003

Basic study on vibrations during tooth preparations caused by high-speed drilling and Er:YAG laser irradiation.

BACKGROUND AND OBJECTIVES: An Er:YAG laser effectively removes dental hard substance, and causes less pain during tooth preparations than high-speed drilling. This laser was introduced to eliminate the noise, vibration, pressure, and heat associated with the high-speed drilling. However, the difference in tooth vibration caused by the Er:YAG laser and the high-speed drill is unclear. Therefore, the aim of this study was to evaluate tooth vibration obtained with the Er:YAG laser and high-speed drill. STUDY DESIGN/MATERIALS AND METHODS: Each of the five extracted permanent upper first premolars were built up in a plaster box. In this study, a silicone impression material was selected to simulate periodontal tissue. The vibration speed was measured by using a laser Doppler vibrometer. RESULTS: The Er:YAG laser irradiation energy was 50, 100, 145, 199, 300, and 350 mJ. As irradiation energy increased, vibration of the tooth also rose; a high-correlation coefficient was observed between them. We found that only a small amount of the tooth vibration occurred with the Er:YAG laser preparations. The mean vibration speed and standard deviation with the laser were 166 +/- 28 microm/second when the output energy was 145 mJ, whereas those with the high-speed drill were 65 +/- 48 mm/second. The frequency characteristic approached 230 Hz and 5 kHz, respectively. CONCLUSIONS: These results show that the high-speed drilling causes greater tooth vibration and has a frequency spectrum near the high sensitivity of hearing compared to the Er:YAG laser. This suggests a potential factor in provoking pain and displeasure during tooth preparation. Future study to examine the relationship of pain and amount of tooth vibration will be planned.

Dental Instruments↗
PubMed2003

Effects of Wulst and ectostriatum lesions on repeated acquisition of spatial discrimination in pigeons.

The avian telencephalon has two visual areas, (1) a 'Wulst' that consists of hyperstriatum accessorium, hyperstriatum intercalatus superior and hyperstriatum dorsale, and (2) the ectostriatum. Deficits in visual discrimination have been observed after ectostratal lesions but not after Wulst lesions. In the present experiments, the cognitive functions of the Wulst in pigeons were examined. Pigeons were trained on repeated acquisition of a three key discrimination. Every time the subjects reached the criterion of discrimination, they were trained on different discriminations in which one of two previously incorrect keys became the correct key. The Wulst lesions disrupted the acquisition of discrimination, while the ectostriatal lesions did not.

Animals↗
PubMed2003

Induction of apoptosis and ubiquitin hydrolase gene expression by human serum factors in the early phase of acute myocardial infarction.

The physiologic events leading to apoptosis in myocardial infarction and the molecules involved in the death process have not been clarified unequivocally. We developed a method to search for serum factors that induce apoptosis of human cells, using serum obtained from patients within 1 day of the onset of acute myocardial infarction (AMI). Serum factors were found to have the ability to increase the caspase-3 activity levels in human RSa cells, which are susceptible to apoptosis inducers. The factors obtained from AMI patients by elution at about 0.5 mol/L KCl from a dye-ligand column were named AMI-SFs (serum factors from AMI). Electrophoretic analysis showed DNA fragmentation in AMI-SF-treated RSa cells, but not in RSa cells treated with fractions from AMI patients 1 week after clinical onset of illness. AMI-SF-induced DNA fragmentation was also demonstrated by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling analysis, whereas a suppression of fragmentation was seen in RSa cells treated with AMI-SFs in combination with a caspase-3 inhibitor. The increase in caspase-3 activity was not inhibited by neutralizing antibodies to tumor necrosis factor-alpha, interleukin-6, human interferon-beta, or interferon-gamma. Polymerase chain reaction-based messenger RNA differential display and Northern blotting revealed an increase in the messenger RNA expression level of human ubiquitin hydrolase in AMI-SF-treated RSa cells. Antisense oligonucleotides for ubiquitin hydrolase inhibited the increase in caspase-3 activity. These findings suggested that serum from AMI patients in the acute phase contains factors that induce apoptosis, possibly by inducing the expression of the ubiquitin hydrolase gene, at least in the human cells tested.

Adult↗
PubMed2003

An immnosuppressive drug, cyclosporine-A acts like anti-depressant for rats under unpredictable chronic stress.

Rats were subjected to unpredictable chronic stress (UCS), which was composed of 3 cycles of 7 kinds of stress for 21 days. Rats given UCS exhibited a depressive state in behavioral tests such as emergence tests and forced swim tests. Administration of cyclosporine-A (CsA), an immunosuppressive drug, gave rise to antidepressant effect in rats under the UCS, but not in stress-free rats. In other words, CsA shortened both the latency time in emergence tests and the immobility time in forced swim tests in rats given UCS. Analysis of brain tissue by HPLC revealed that CsA caused a significant increase in NE, 5-HT and 5-HIAA levels in the cortex of UCS treated rats, but treatment with either UCS or CsA alone resulted in the opposite effect. Comparing the data of monoamines and their metabolites in the brain, cascades may be different between CsA and imipramine, although both of them showed antidepressive effect in behavioral tests.

Adrenal Glands↗
PubMed2002

Preference for mirror images and video image in Java sparrows (Padda oryzivora).

Java sparrows were exposed to a mirror and a frosted mirror, a mirror and a live bird, a mirror and a live bird with frosted screen, a closed circuit TV monitor and a TV program or the closed circuit monitor and an upside down monitor. The birds showed strong preference for the self-image on the mirror, the live bird and the self-image on the monitor. They preferred almost equally to the mirror and the frosted live bird. These results suggest that the Java sparrows saw the self-image on the mirror as conspecific image.

Journal Article↗