假细锥香茶菜新二萜成分——假细锥甲素的结构

从假细锥香茶菜(Rabdosia coetsoides C.Y.Wu)叶分离得到新二萜成分,根据紫外光谱、红外光谱、质谱、核磁共振氢谱及碳谱等分析,推定了化学结构,并经X-射线衍射确证,命名为假细锥甲素。     

Les réseaux sociaux

Résumé: On peut définir trois grands types de réseaux sociaux où interagissent les grands secteurs du social (prise en charge des jeunes, personnes agées, handicapées, insertion des adultes). La qualité de l’articulation entre ces différents types de réseaux peut optimiser la prise en charge des personnes malades et favoriser leur accompagnement. Toutefois, il existe de fortes inégalités d’accès à ces réseaux, ce qui demande une expertise de l’intervention sociale afin de traduire les besoins exprimés en termes opératoires. L’avenir des réseaux est conditionné par l’affinement de leurs connexions avec les réseaux de soins émergents et laisse entrevoir une nouvelle culture professionnelle.      

Effect of levodopa on pain threshold in Parkinson's disease: a clinical and positron emission tomography study.

Patients suffering from Parkinson's disease (PD) frequently experienced painful sensations that could be in part due to central modification of nociception. We compared pain threshold before and after administration of levodopa in PD patients and in controls, and investigated cerebral activity with positron emission tomography (PET) during experimental nociceptive stimulation. Pain threshold was determined using thermal stimulation during two randomized conditions: off and on. We performed H(2) (15)O PET analysis of regional cerebral blood flow on subjects while they received alternate randomized noxious and innocuous stimuli during off and on conditions. In off condition, pain threshold in nine PD patients was significantly lower than in nine controls. Administration of levodopa significantly raised pain threshold in PD patients but not in controls. During off condition, there was a significant increase in pain-induced activation in right insula and prefrontal and left anterior cingulate cortices in PD compared to control group. Levodopa significantly reduced pain-induced activation in these areas in PD. This study shows that pain threshold is lower in PD patients but returns to normal ranges after levodopa administration. Moreover, PD patients have higher pain-induced activation in nociceptive pathways, which can be reduced by levodopa.     

Physiological responses to repeated apneas in underwater hockey players and controls.

The aim of this study was to investigate the effects of short repeated apneas on breathing pattern and circulatory response in trained (underwater hockey players: UHP) and untrained (controls: CTL) subjects. The subjects performed five apneas (A1-A5) while cycling with the face immersed in thermoneutral water. Respiratory parameters were recorded 1 minute before and after each apnea and venous blood samples were collected before each apnea and at 0, 2, 5 and 10 minutes after the last apnea. Arterial saturation (SaO2) and heart rate were continuously recorded during the experiment. Before the repeated apneas, UHP had lower ventilation, higher P(ET)CO2 (p < 0.05) and lower P(ET)O2 than CTL (p < 0.001). After the apneas, the P(ET)O2 values were always lower in UHP (p < 0.001) than CTL but with no difference for averaged P(ET)CO2 (p = 0.32). The apnea response, i.e., bradycardia and increased mean arterial blood pressure, was observed and it remained unchanged throughout the series in the two groups. The SaO, decreased in both groups during each apnea but the post-exercise SaO2 values were higher in UHP after A2 to A5 than in CTL (p < 0.01). The post-apnea lactate concentrations were lower in UHP than in CTL. These results indicate that more pronounced bradycardia could lead to less oxygen desaturation during repeated apneas in UHP. The UHP show a specific hypoventilatory pattern after repeated apneas, as well as a more pronounced cardiovascular response than CTL. They indeed showed no detraining of the diving response.     

Cytogenetic and genetic effects of subchronic treatments with organophosphorus insecticides

Male mice (Q strain) received 5 days a week for 7 weeks drinking water containing dichlorvos (2 ppm), dimethoate (0.6 ppm), malathion (8 ppm), methylparathion (0.15 ppm), or trichlorfon (0.5 ppm). At the end of the treatment, no chromosome damage was observed in bone marrow cells, spermatogonia, and primary spermatocytes. Dominant lethal mutation assays were performed to investigate the pre- and postimplantation foetal lethality. Only negative results were obtained.     

Peripheral lymphocytes changes in the anamnestic response to tetanus toxoid challenge.

Few data are available on the blood lymphocyte response to revaccination in man. The anamnestic response to tetanus toxoid challenge was evaluated by a variety of techniques during the first week after revaccination. Out of twenty subjects used, eight were evaluated before and 5 days after the injections (days 1--8). Analytical cell electrophoresis showed important variation in the B and two T lymphocyte populations. The B cell percentages, assessed by EAC-rosettes and electrophoretic mobility, were found to decrease by days 2 and 3, and return to former levels by day 8, when a rise in specific antibodies was detected. A similar response was found in the T1 population generally considered to be composed of low affinity E-rosette-forming cells. Conversely, a significant increase (50--100%) in circulating T2 lymphocytes (active rosette-forming cells) was found by days 2 and 3, followed by a rapid decrease of these 'differenciated' cells. The increase in the T2 lymphocytes appeared earlier in skin test positive subjects. These changes were correlated with E-rosettes, mitogen stimulation, peripheral leucocyte migration inhibition and transformation in the presence of the antigen. EA-IgG rosettes and ADCC varied similarly. These results may indicate a significant non-specific cell mobilization following revaccination.