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431.
Neuropeptide S (NPS) and its receptor were recently discovered in the central nervous system. In rodents, NPS promotes hyperlocomotion, wakefulness, anxiolysis, anorexia, and analgesia and enhances memory when injected intracerebroventricularly (i.c.v.). Herein, NPS at different doses (0.01, 0.1 and 1 nmol) was i.c.v. administered in mice challenged with pentylenetetrazole (PTZ; 60 mg/kg) repeatedly injected. Aiming to assess behavioral alterations and oxidative damage to macromolecules in the brain, NPS was injected 5 min prior to the last dose of PTZ. The administration of NPS only at 1 nmol increased the duration of seizures evoked by PTZ, without modifying frequency and latency of seizures. Biochemical analysis revealed that NPS attenuated PTZ-induced oxidative damage to proteins and lipids in the hippocampus and cerebral cortex. In contrast, the administration of NPS to PTZ-treated mice increased DNA damage in the hippocampus, but not cerebral cortex. In conclusion, this is the first evidence of the potential proconvulsive effects of NPS in mice. The protective effects of NPS against lipid and protein oxidative damage in the mouse hippocampus and cerebral cortex evoked by PTZ-induced seizures are quite unexpected. The present findings were discussed analyzing the paradoxical effects of NPS: facilitation of convulsive behavior and protection against oxidative damage to lipids and proteins.  相似文献   
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Gestational hypothyroidism is a prevalent disorder in pregnant women. We aimed to investigate the impact of experimental gestational hypothyroidism (EGH) on cardiovascular and autonomic nervous systems (ANS) in the offspring of rats. EGH was induced with methimazole (MMI) 0.02% in drinking water from day 9 of gestation until birth. Sixty day old offspring from MMI-treated dams (OMTD, n=13) or water-treated dams (OWTD, n=13) had femoral arteries surgically assessed for the measurements of heart rate (HR), mean (MAP), systolic (SAP) and diastolic arterial pressure (DAP), and spontaneous baroreflex sensitivity (BRS). To investigate the balance of ANS, we established the high (HF) and low frequency (LF) bands of pulse interval (PI) and LF band of SAP spectrum. OMTD had increased MAP (130.2±2.0 vs 108.8±3.0mmHg, p<0.001), SAP (157.3±2.9 vs 135.7±4.5mm Hg, p<0.001) and DAP (109.7±1.9 vs 88.4±2.6mmHg, p<0.001) when compared to OWTD, and had lower HR (355.1±8.9 vs 386.8±9.2bpm, p<0.05). After spectral analysis of PI and SAP, only LF band of SAP spectrum was higher (7.2±0.8 vs 4.0±0.6mmHg(2), p<0.01) in OMTD under spontaneous condition. Despite bradycardia, EGH promotes spontaneous hypertension in 60day old offspring, probably due to increased sympathetic modulation of vessels, which is suggested by the higher LF of SAP. These findings suggest a critical role of maternal THs in the development of fetal cardiovascular and autonomic nervous systems.  相似文献   
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Unlike previous emotional studies using functional neuroimaging that have focused on either locating discrete emotions in the brain or linking emotional response to an external behavior, this study investigated brain regions in order to validate a three-dimensional construct--namely pleasure, arousal, and dominance (PAD) of emotion induced by marketing communication. Emotional responses to five television commercials were measured with Advertisement Self-Assessment Manikins (AdSAM) for PAD and with functional magnetic resonance imaging (fMRI) to identify corresponding patterns of brain activation. We found significant differences in the AdSAM scores on the pleasure and arousal rating scales among the stimuli. Using the AdSAM response as a model for the fMRI image analysis, we showed bilateral activations in the inferior frontal gyri and middle temporal gyri associated with the difference on the pleasure dimension, and activations in the right superior temporal gyrus and right middle frontal gyrus associated with the difference on the arousal dimension. These findings suggest a dimensional approach of constructing emotional changes in the brain and provide a better understanding of human behavior in response to advertising stimuli.  相似文献   
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This study compared hip rotation range of motion in judo athletes with and without a history of low back pain. Forty-two athletes (22 males) were divided into two groups: 21 with history of low back pain (HLBP) and 21 without history of low back pain (Control). Internal and external hip rotation range of motion in active and passive movement were measured using computed photogrammetry. The HLBP group exhibited a significant reduction in active internal rotation (27.5 ± 6.5° vs 38.2 ± 6.5°), active total rotation (80.1 ± 9.5° vs 87.4 ± 7.9°) of the non-dominant limb (P < 0.01) and active total rotation (82.6 ± 7.6° vs 87.6 ± 9.8°; P = 0.04) in comparison with the control group. In passive rotation, the HLBP group showed a significant reduction in internal rotation of the dominant (41.9 ± 6.1° vs 46.1 ± 8.4°; P = 0.04) and non-dominant limb (37.1 ± 8.4° vs 47.3 ± 7.6°; P < 0.001), total rotation of the non-dominant limb (96.7 ± 10.2° vs 105.1 ± 11°; P = 0.005) and total rotation (98.5 ± 9.2° vs 105 ± 11.2°; P = 0.02). Within the HLBP group, a significant reduction in both active and passive internal rotation (P < 0.001) and active and passive total rotation (P < 0.01) of the non-dominant limb was detected. The same was not found in the control group. The results demonstrate that judo athletes with a history of low back pain exhibit deficits in hip rotation and greater asymmetry between limbs.  相似文献   
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The purpose of the present study was to assess the bond strength of composite resin repairs subjected to different surface treatments and accelerated artificial aging. 192 cylindrical samples (CSs) were prepared and divided into 24 groups (n = 8). Half of the CSs were stored in water for 24 h, and the other half were subjected to C-UV accelerated aging for non-metallic specimens. The treatments were phosphoric acid + silane + adhesive (PSA); phosphoric acid + adhesive (PA); diamond bur + phosphoric acid + silane + adhesive (DPSA); diamond bur + phosphoric acid + adhesive (DPA); air abrasion + phosphoric acid + silane + adhesive (APSA); and air abrasion + phosphoric acid + adhesive (APA). The repair was performed and the specimens were again aged as described above. A control group (n = 8) was established and did not receive any type of aging or surface treatment. The specimens were loaded to failure in shear mode with a crosshead speed of 0.5 mm/min until fracture. Data were analyzed by one-way ANOVA/Tukey's test (p < 0.05). No statistically significant differences were found among DPSA, DPA, APSA, APA, and the control group. The aged PSA and PA achieved low bonding values and were statistically different from the control group, whereas the non-aged PSA and PA presented no statistically significant difference from the control group. Repairs with the proposed surface treatments were viable on both recent and aged restorations; however, phosphoric acid + adhesive alone were effective only on recent restorations.  相似文献   
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