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Journal Article 2010; 31(6): 807-813 PubMed PMID: 21196910 Citation  Keywords:  Absorptiometry, Photon:methods, Animals, Bone Density, Bone Remodeling, Bone Resorption, Calcium:blood, Disease Models, Animal, Electric Stimulation:methods, Foot, Injections, Intraperitoneal, Male, Neuropsychological Tests, Norepinephrine:blood, Osteocla.   

OBJECTIVES: Bone remodeling has recently been revealed to be under sympathetic nerve control. The role of the sympathetic nerve system is not clearly understood. The present study aim to explore the effect of chemical sympathectomy and stress on bone remodeling in adult rats.

METHODS: 24 twelve-month-old Wistar rats were divided into three group (sympathectomy, stress and control). The sympathectomy and stress group rats were administered 6-hydroxydopamine (150 mg/kg each day) and saline (1 ml/kg each day) intraperitoneal respectively for one week and exposed to stress procedure for another three weeks. The stress procedure was mild, unpredictable footshock, administered for one hour once daily. Analysis of serum chemistry, microcomputed tomography, dual energy X-ray absorptiometry, biomechanical testing and bone histomorphometry were employed.

RESULTS: The stress group rats showed increased bone resorption in contrast to the sympathectomy and control group rats. The serum level of calcium and phosphorus cations and norepinephrine were enhanced, the cancellous bone volume and bone mineral density were reduced, bone mechanical property such as strength, ductility and toughness were weakened, the osteoclast counts and osteoclast surfaces were increased and the bone formatin rate were decreased significantly in the stress group rats in contrast to the other two groups rats. There was no significant difference of bone remodeling between the sympathectomy group and control group rats.

CONCLUSION: Our study showed stress-increased sympathetic nerve system activity enhanced bone resorption while chemical sympathectomy inhibited bone resorption under stress. We postulate sympathetic neurotransmitter and neuropepitide may play a role in regulating bone remodeling....

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Clinical Trial 2010; 31(1): 161-167 PubMed PMID: 20150864 Citation  Keywords:  Adult, Brain Mapping:methods, Cerebral Cortex:metabolism, Cystine:analogs & derivatives, Estrogen Replacement Therapy, Female, Humans, Hypothyroidism:diagnosis, Male, Neuropsychological Tests, Prognosis, Severity of Illness Index, Technetium:chemistry, Th.   

OBJECTIVE: The purpose of this study was to correlate hypothyroid-related symptomatology with regional cerebral blood flow (rCBF) during hypothyroidism.

MATERIALS AND METHODS: Nine thyroidectomized patients underwent neuropsychological testing and single photon emission computed tomography (SPECT) of their brains with technetium-99m (Tc-99m) ethyl cysteinate dimer (ECD), a lipophilic cerebral blood flow radiotracer, while hypothyroid, and again following thyroid hormone replacement. Neuropsychological test scores and TSH levels while hypothyroid were correlated with rCBF in hypothyroid-affected areas of the brain.

RESULTS: Correlations were found during hypothyroidism between the noted parameters and ECD radiotracer accumulation in the following respective regions, all of which demonstrated hypothyroid-related cerebral blood flow (CBF) aberrations: TSH and left middle occipital gyrus; psychomotor performance speed and left precentral gyrus; and depression and right middle frontal gyrus, left middle frontal gyrus, right insula, and left thalamus.

CONCLUSIONS: Severity of psychomotor impairment and depression, and TSH level during hypothyroidism appeared to correlate with CBF to brain regions associated with motor activity, mood and vision, respectively; and previously shown to manifest significantly altered rCBF during hypothyroidism....

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Controlled Clinical Trial 2009; 30(1): 125-130 PubMed PMID: 19300388 Citation  Keywords:  Adult, Diet, Dietary Supplements, Female, Humans, Male, Pattern Recognition, Visual:drug effects, Photic Stimulation, Phytoestrogens:administration & dosage, Psychological Tests, Rotation, Sex Characteristics, Soy Foods, Space Perception:drug effects, Tas.   

INTRODUCTION: It is well known that men outperform women in tests of spatial cognition, such as mental rotation, and that performance in these tasks is influenced by sexual hormones. Phytoestrogens are plant substances chemically similar to estradiol, capable of binding estrogen receptors. In a previous study, one-week phytoestrogen-rich diet improved performance in mental rotation in women, but it remained unclear whether this was due to direct binding of phytoestrogens to estrogen receptors or by modulating testosterone blood levels.

OBJECTIVES: We investigated whether one week consumption of phytoestrogens will equally affect performance in mental rotation in women and men. We expected improved performance in women, but unchanged skill in men, if the effects were mediated by changes of testosterone level. On the other hand, direct modulation of estrogen receptors should yield comparable improvement in both genders.

METHODS: Thirty-six healthy adult young volunteers (16 females) were divided into the control and soy groups. During 7 consecutive days, in addition to their usual diet, subjects in the soy group consumed a daily dose of 2 g of soybeans per kilogram body weight (about 170 mg/kg of isoflavones). The control group members stayed on their usual diet. The subjects were tested on mental rotation of letters and digits at the baseline and after 7 days of soy consumption.

RESULTS: Consumption of soy had no influence on performance in the mental rotation task. For the intermediate stimulus rotation angle (60 deg), irrespective of soy intake, improvement of response latencies was greater in women than in men.

CONCLUSION: The results indicate that soy phytoestrogens have little impact on mental rotation skill. The findings also suggest that women, in contrast to men, more readily engage memory mechanisms to solve the mental rotation task....

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Comparative Study 2009; 30(1): 25-31 PubMed PMID: 19300387 Citation  Keywords:  Animals, Anti-Anxiety Agents:pharmacology, Anxiety:drug therapy, Behavior, Animal:drug effects, Diazepam:pharmacology, Exploratory Behavior:drug effects, Male, Motor Activity:drug effects, Neuropsychological Tests, Rats, Rats, Wistar,.   

OBJECTIVES: Anxiety is an emotional state experienced by people, and is not readily modeled in animals. In order to extend till now ethologically derived paradigms used in the evaluation of anxiety and fear in rodents, a modified open-field was designed.

METHODS: Spontaneous behavior of male rats was investigated in the elevated arena; the bottom was divided by inter-space of different width (2, 4, 6, 8 and 10 cm) into two identical parts. Anxiolytic effects of diazepam (DZP) at doses 0.5, 1.0, 2.5 and 5.0 mg/kg were investigated in the newly designed device and compared with the effects of similar doses in a large circular open-field arena.

RESULTS: In Experiment 1 the progressive extension of the inter-space prolonged the first passing, decreased the total number of passing, and increased the inter-space sniffing in intact animals. In Experiment 2 DZP at doses 1.0, 2.5 and 5.0 mg/kg significantly enhanced the readiness to cross, the frequency of passing the inter-space and decreased inter-space sniffing as compared to controls. In Experiment 3 we found that DZP at doses 0.1 and 0.3 mg/kg increased behavioral activity both along the perimeter and in the center of the arena, thus indicating lower level of anxiety.

CONCLUSION: The presented modified open-field test is a useful paradigm to investigate risk assessment behavior in rats, and may provide a sensitive novel model of anxiety and fear level....

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Journal Article 2009; 30(6): 749-752 PubMed PMID: 20038936 Citation  Keywords:  Alcohol Drinking:psychology, Behavior, Addictive:psychology, Decision Making, Female, Humans, Impulsive Behavior:psychology, Male, Neuropsychological Tests, Probability, Risk-Taking, Young Adult,.   

OBJECTIVE: Little is known about the relationship between alcohol and discounting of loss, one of procrastinative behaviors. This study examined the relationship between the frequency of alcohol use and discounting delayed and probabilistic gain and loss, which is of interest in neuroeconomics of addiction.

METHODS: Thirty-three subjects conducted tasks of delay and probability discounting of gain and loss. Their alcohol use was also assessed.

RESULTS: The frequency of alcohol use was significantly correlated with the degree to which delayed monetary losses were discounted.

CONCLUSIONS: Frequent use of alcohol may associate with an increased degree of procrastination. Further, the degrees of delay discounting of loss could be a predictor of a frequent alcohol intake....

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Journal Article 2009; 30(5): 643-646 PubMed PMID: 20035253 Citation  Keywords:  Adolescent, Choice Behavior:physiology, Decision Making:physiology, Emotions:physiology, Female, Games, Experimental, Humans, Neuropsychological Tests, Saliva:enzymology, Salivary alpha-Amylases:metabolism, Young Adult,.   

OBJECTIVES: This study aimed to examine the role of emotions in rejection of unfair offers in an ultimatum game, which is of interest in neuroeconomics of fairness.

METHODS: Thirty-seven participants played a one-shot ultimatum game as responders and decided whether to accept or reject the unfair offers by the proposers. Salivary alpha-amylase (sAA) was assessed before and after the ultimatum game.

RESULTS: Forty-four percent of the participants rejected the unfair offers. While sAA levels of the participants who rejected the unfair offers increased between pre- and post-experiment, sAA levels of the participants who accepted the unfair offers remain unchanged.

CONCLUSIONS: Emotional stress response was observed when participants rejected the unfair offers. Our results indicated that rejection of the unfair offers is a reflection of emotional arousal associated with adrenergic activations....

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Journal Article 2009; 30(3): 409-413 PubMed PMID: 19855369 Citation  Keywords:  Activities of Daily Living, Aged, Dementia:drug therapy, Geriatric Assessment, Humans, Neuropsychological Tests, Psychiatric Status Rating Scales, Severity of Illness Index, Treatment Outcome,.   

BACKGROUND: An effort to share our many years of clinical experience.

OBJECTIVE: To predict the effectiveness of medication in advanced phases of dementia in the light of pharmaceutical economics and to find the most suitable alternative treatments.

METHODS: Use of 3 commonly available geriatric tests Mini-Mental State Examination (MMSE), Activity of Daily Living (ADL) and Instrumental Activity of Daily Living (IADL). Threshold values of these tests, after mathematical transformation to comparable values, enables calculation of the hypothetical Point of Reversibility Pr found on the range here called MEKO.

RESULTS: Estimated values of SD can be used to choose the most effective medical treatment.

CONCLUSION: Beyond the upper threshold of S(D), on the basis of the above mentioned method, continued medication is of dubious value....

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Journal Article 2008; 29(4): 507-511 PubMed PMID: 18766150 Citation  Keywords:  Animals, Behavior, Animal:physiology, Chickens, Female, Learning:physiology, Mothers, Neuropsychological Tests, Odorants, Placebos, Social Isolation, Stress, Psychological,.   

: A synthetic analogue of a mother-hen odour named MHUSA (Mother Hen Uropygial Secretion Analogue) reduces stress-related behaviour in the chicken. We hypothesize that MHUSA may have an attractant effect on chicks. In order to test this, 30 chicks were individually exposed to MHUSA, placebo or neutral when self isolated in a straight shuttle box. The location of the chicks within the test chamber was recorded with 360 consecutive scan-sampled images. During the first three minutes immediately after introduction to the test area chicks spent more time in the neutral zone (p<0.05). However, taking the results from the total observation period, chicks spent more time in the MHUSA and placebo zones combined than in the neutral zone (p=0.07). They were more often observed in the MHUSA zone compared to the placebo zone (p<0.05). These results suggest that during the first three minutes in the shuttle, individuals were adapting to their new environment. After this period, chicks directed themselves towards specific local stimuli, as they tried to reach their group or something that resembled it. After a stressor was introduced, we observed a return to the same situation as during the first three minutes of the test, with chicks returning to the neutral zone, suggesting that the chick had its confidence in the environment. Three main conclusions may be drawn. Firstly, MHUSA has an attractant effect on naïve chicks. Secondly, it appears to play a role in the reaction of chicks faced with a stressful event, and finally, the reaction to MHUSA seems innate and does not require previous experience....

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