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1.
Abnormal spinal interactions from hand afferents to forearm muscles in writer's cramp. 总被引:1,自引:0,他引:1
G Louren?o J-P Bleton C Iglesias M Vidailhet V Marchand-Pauvert 《Clinical neurophysiology》2007,118(10):2215-2226
OBJECTIVE: Spinal reflexes from hand to wrist muscles were investigated in writer's cramp. METHODS: Stimulus-triggered rectified EMG averages after ulnar nerve and cutaneous stimulation, in wrist flexors and extensors during tonic contraction, were compared in 18 controls and 19 patients. RESULTS: On the patient dystonic side, ulnar-induced EMG suppression was decreased in wrist extensors, and facilitation in wrist flexors modified dependent on the dystonic wrist posture during writing. No change was found on the patient non-dystonic side. Cutaneous stimulation increased wrist flexor EMG on both sides of the patients with normal wrist posture during writing, but had no effect in controls and patients with abnormal wrist posture. CONCLUSIONS: Comparison between cutaneous and mixed nerve stimuli suggests that spindle afferents from intrinsic hand muscles may mediate patients' ulnar-induced EMG modulations. Abnormal proprioceptive control was only observed on dystonic side, while bilateral unusual cutaneous control was found in patients. Changes in spinal transmission were partly related to the dystonic wrist posture, suggesting that systems involved in sensory processing can be differentially altered in writer's cramp. SIGNIFICANCE: Changes in spinal transmission, probably related to peripheral and/or cortical inputs, might either take part in primary or adaptive mechanisms underlying writer's cramp. 相似文献
2.
Haloperidol is a receptor D2 antagonist frequently used in the treatment of schizophrenic patients. Haloperidol increased prolactin release from anterior pituitary gland, and prolactin modulates immune system activity. Groups of six male and female rats received an acute 2 mg/kg haloperidol treatment (E1), or a long-term (E2) haloperidol treatments (2 mg/kg/day for 21 days); control rats were treated similarly, but with control solution (groups C1 and C2, respectively). In this work long-term haloperidol treatment (E2) increased macrophage spreading, phagocytosis and NO release in male and female rats. However, acute haloperidol treatment (E1) did not change macrophage activity. Corticosterone and prolactin serum levels were increased after acute (E1) and long-term (E2) haloperidol treatments in male and female rats, being this increment higher in female. Macrophage of male and female rats presented the same pattern of alterations after acute and long-term haloperidol treatments. Haloperidol-induced macrophage activation was discussed in the light of a possible indirect effect through prolactin increments in rats, or, alternatively, as a consequence of a direct action of macrophage dopamine receptor. 相似文献
3.
George Lourenço PhD Sabine Meunier MD PhD Marie Vidailhet MD PhD Marion Simonetta‐Moreau MD PhD 《Movement disorders》2007,22(4):523-527
A decrease of heteronymous median nerve-evoked inhibition of corticospinal projections to forearm extensor muscles was reported in a group of 10 dystonic patients by Bertolasi and colleagues in 2003. Here we tested the excitability of corticomotoneuronal connections to both wrist extensor (ECR) and flexor (FCR) muscles after conditioning stimulation of median and also radial nerve at rest in a group of 25 patients with focal hand dystonia compared to 20 healthy subjects. We also investigated the effect of the wrist dystonic posture, either in flexion or in extension, on the afferent modulation of ECR and FCR motor evolved potentials (MEPs). The heteronymous (median-induced) but also homonymous (radial-induced) inhibitions (interstimuli intervals 13-21 ms) of ECR MEP size observed in healthy subjects were decreased in patients. In addition, homonymous (median-induced) facilitation of FCR MEP size was also decreased in patients while heteronymous inhibition (radial-induced) was not. Neither the involvement of the target muscle in the dystonic posture nor the origin of the afferent volley (from a dystonic muscle) influenced the degree of impairment of afferent modulation of the MEP. These findings support the view that a global abnormal somatosensory coupling in focal hand dystonia may contribute to an inadequate motor command to wrist muscles. 相似文献
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Martins LM Peltre G da Costa Faro CJ Pires EM da Cruz Inácio FF 《International archives of allergy and immunology》2005,136(1):7-15
BACKGROUND: Ingestion of snails can induce strong asthmatic or anaphylactic responses, mainly in house-dust-mite-sensitized patients. The aim of this study was to identify the Helix aspersa (Hel a), Theba pisana (The p) and Otala lactea (Ota l) allergens and the extent of their cross-reactivity with the Dermatophagoides pteronyssinus (Der p) mite. PATIENTS AND METHODS: In 60 atopic patients, skin prick tests (SPT) to snail and D. pteronyssinus, total and specific IgE, specific IgE immunoblots, RAST and immunoblot inhibition assays were performed. RESULTS: Mean total IgE was >1,000 kU/l. Mean specific IgE (class 6 for Der p and class 2 for Hel a) SPT were positive in 44 patients for snail and in 56 for mite. Isoelectric focusing (IEF) and SDS-PAGE followed by immunoblotting of H. aspersa extract enabled the identification of 27 and 20 allergens, respectively. Myosin heavy chains from snails (molecular weight >208 kDa) disclosed two major allergens. Hel a and Der p RAST were strongly inhibited by their homologous extracts, with Hel a RAST being inhibited by the Der p extract to a much greater extent (72.6%) than the inverse (5.6%). A complete inhibition of the immunoblots by their homologous extract was obtained. However, Hel a extract did not inhibit Der p IEF separated recognition. On the other hand, mite extract extensively inhibited snail immunoblots from both IEF and SDS-PAGE separations. Immune detection on chicken, pig, rabbit, cow and horse myosins did not reveal any IgE cross recognition with snail. CONCLUSIONS: In most cases of snail allergy, mite appeared to be the sensitizing agent. Nevertheless, snails may also be able to induce sensitization by themselves. This hypothesis is supported by the finding of specific IgE to Hel a in 2 patients who did not show specific IgE to Der p, and one of them was suffering from asthma after snail ingestion. 相似文献
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7.
Ludmylla Cunha Ana M. Rosa da Costa João P. Lourenço Francesca Buttini 《Journal of microencapsulation》2018,35(4):392-405
Pulmonary tuberculosis accounts for 80% of cases and the delivery of antitubercular drugs into the lungs allows targeting the infected organ and, possibly, reducing systemic drug toxicity. This work aimed at using fucoidan as matrix of inhalable microparticles that associate two first-line antitubercular drugs, for an application in pulmonary tuberculosis therapy. Fucoidan is composed of fucose and sulphated sugar residues, moieties described as being recognised by surface receptors of alveolar macrophages, which host mycobacteria. Inhalable fucoidan microparticles loaded with antitubercular drugs were successfully produced with high association efficiencies of either isoniazid (95%) or rifabutin (81%). The microparticles evidenced no cytotoxicity on lung epithelial cells (A549). However, rifabutin-loaded microparticles showed a certain degree of toxicity on macrophage-like cells (THP-1) at the highest tested concentration (1?mg/mL). Furthermore, microparticles showed favourable aerodynamic properties for deep lung delivery (MMAD 2.0–3.8?µm) and, thus, show potential for an application as inhalable tuberculosis therapy. 相似文献
8.
Bisphenol A release from orthodontic adhesives measured in vitro and in vivo with gas chromatography
9.
Previous evidence suggests that variants in the fat mass and obesity-associated gene (FTO) affect adiposity in an age-dependent fashion in children, and nutritional factors may modify genotype effects. We assessed the effect of FTO rs9939609 on BMI and BMI-for-age Z score changes during childhood in a population-based longitudinal study in the Brazilian Amazon and investigated whether these effects were modified by vitamin D status, an important nutritional factor related to adiposity. At baseline, 1,088 children aged <10 years had complete genotypic and anthropometric data; 796 were followed up over a median 4.6 years. Baseline vitamin D insufficiency was defined as <75 nmol/L. We observed a 0.07 kg/m2/year increase in BMI and a 0.03 Z/year increase in BMI-for-age Z score per rs9939609 risk allele over follow-up (P = 0.01). Vitamin D status significantly modified FTO effects (P for interaction = 0.02). The rs9939609 risk allele was associated with a 0.05 Z/year increase in BMI-for-age Z score among vitamin D–insufficient children (P = 0.003), while no significant genetic effects were observed among vitamin D–sufficient children. Our data suggest that FTO rs9939609 affects child weight gain, and genotype effects are more pronounced among children with insufficient vitamin D levels. 相似文献
10.
M.M.S. Nico J.N. Melo S.V. Lourenço 《Journal of the European Academy of Dermatology and Venereology》2014,28(3):382-387
Background Cheilitis glandularis (CG) is a rare condition in which thick saliva is secreted from dilated ostia of swollen minor salivary glands from the lips. Aquaporins (AQPs) are membrane proteins that exhibit channel activity specific for water and small solutes. AQPs are essential for corporal homeostasis, and are widely expressed through human tissues. Most AQPs studies are based on renal and nervous pathophysiology; few involve salivary glands. Some previous investigators hypothesized that minor salivary gland structure and function is normal on CG. Objectives To study possible salivary synthesis alterations in CG, we compared the expression of AQPs present in minor salivary glands in specimens with CG and controls by using immunohistochemistry. Methods Seven cases of CG and three normal controls were studied. Results Intensity and patterns of expression of AQP 1, 2 and 8 differed in CG compared with controls. AQP 4 and 5 (the most important AQP in salivary function) showed identical patterns in CG and controls. Conclusion Our findings suggest that the expression and arguably, function of some of the AQPs may be altered in CG; consequently, water flow mechanism abnormalities with possible alteration in salivary composition seem to occur. External factors (mainly UV rays) seem to play an important role in CG; nonetheless, our findings suggest that there might be some degree of alteration on water transportation. 相似文献