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Luisa Rocha Manola Cuellar-Herrera Marcos Velasco Francisco Velasco Ana-Luisa Velasco Fiacro Jiménez Sandra Orozco-Suarez Anna Borsodi 《Seizure》2007,16(7):645-652
Opioid receptor binding was evaluated in parahippocampal cortex (PHC) obtained from patients with intractable mesial temporal lobe epilepsy (MTLE) with and without subacute high frequency electrical stimulation (HFS) in this brain area. Mu, delta and nociceptin receptor binding was determined by autoradiography in PHC of five patients (ESAE group) with MTLE history of 14.8 +/- 2.5 years and seizure frequency of 11 +/- 2.9 per month, two of them (40%) with mesial sclerosis. This group demonstrated antiepileptic effects following subacute HFS (130 Hz, 450 micros, 200-400 microA), applied continuously during 16-20 days in PHC. Values were compared with those obtained from patients with severe MTLE (history of 21.7 +/- 2.8 years and seizure frequency of 28.2 +/- 14 per month) in whom electrical stimulation did not induce antiepileptic effects (ESWAE group, n = 4), patients with MTLE in whom no electrical stimulation was applied (MTLE group, n = 4) and autopsy material acquired from subjects without epilepsy (n = 4 obtained from three subjects). Enhanced 3H-DAMGO (MTLE, 755%; ESAE, 375%; ESWAE, 693%), 3H-DPDPE (MTLE, 242%; ESAE, 80%; ESWAE, 346%) and 3H-nociceptin (MTLE, 424%; ESAE, 217%; ESWAE, 451%) binding was detected in the PHC of all epileptic groups. However, tissue obtained from ESAE group demonstrated lower opioid receptor binding (3H-DAMGO, 44.5%, p < 0.05; 3H-DPDPE, 47%, p < 0.05; 3H-nociceptin, 39.3%, p < 0.5) when compared with MTLE group. The present results indicate that a high effectiveness to the antiepileptic effects induced by HFS is associated with reduced opioid peptide binding. 相似文献
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Ivonne D Flechas Adriana Cuellar Zulma M Cucunubá Fernando Rosas Víctor Velasco Mario Steindel del Carmen María Thomas Manuel Carlos López John Mario González Judith Concepción Puerta 《BMC infectious diseases》2009,9(1):186
Background
Antigen specificity and IgG subclass could be significant in the natural history of Chagas' disease. The relationship between the different stages of human Chagas' disease and the profiles of total IgG and its subclasses were thus analysed here; they were directed against a crude T. cruzi extract and three recombinant antigens: the T. cruzi kinetoplastid membrane protein-11 (rKMP-11), an internal fragment of the T. cruzi HSP-70 protein192-433, and the entire Trypanosoma rangeli HSP-70 protein. 相似文献86.
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Sergio Porcel Carreño Fernando Pineda de la Losa Eva Frontera Carrión Elena Rodríguez Martín Alfonso Ramos Cantariño Ana Sánchez González Ana Rodríguez Trabado Soledad Jiménez Timón Manuela Alvarado Arenas Víctor Medina Velasco María Rodríguez Martín Javier Hernández Arbeiza 《Allergologia et immunopathologia》2009,37(2):68-72
BackgroundAsticot maggot (Blowfly, Calliphoridae family) is the most important live bait used for angling in our country. Prevalence of allergy to live fish bait in occupationally exposed workers has been described. The purpose of this study was to determine the prevalence of asticot allergy in amateur fishermen and the identification of marketed asticot species in Cáceres, Spain.Materials and MethodsSeventy-two randomised selected patients (Angler's Society of Cáceres) completed a questionnaire about fishing habits and allergic symptoms related with live bait handling. Skin prick test (SPT) with local asticot and common earthworm extracts were performed. Serum IgE levels to imported species (Protophormia terraenovae, Calliphora vomitoria, Lucilia sericata, Lumbricus terrestris) were measured. Local asticot and common earthworm samples were obtained for taxonomic identification. Data were analysed using the SPSS 12.0 software.ResultsFive patients (7 %) reported allergic symptoms caused by asticot maggots. All of them were positive for SPT to asticot and specific IgE to P. terraenovae. Sensitisation to P. terraenovae was found in 40 patients (58.8 %). No associated factors for asticot allergy were observed. Larvae and adult flies of local asticot samples were identified as P. terraenovae.ConclusionsCommercially available asticot, in Cáceres, is composed by P. terraenovae larvae (Diptera. Calliphoridae). A 7 % prevalence of P. terraenovae allergy in amateur fishermen of Cáceres was obtained. The allergenic potential of P. terraenovae seems to be greater than that of other blowflies and L. terrestris. The SPT with P. terraenovae extract is a very sensitive and specific technique in the diagnosis of live bait allergy in fishermen. 相似文献
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Asterixis is a motor control disorder characterized by the presence of abnormal movements of the lower limbs in the vertical plane during posture maintenance. Asterixis is usually bilateral and associated with toxic-metabolic metabolic encephalopathies. Unilateral asterixis is less frequent and it normally indicates focal brain damage. We report the cases of four patients (two males/two females), aged 57 to 83 years, suffering from uni or bilateral asterixis associated with focal brain damage. All patients underwent CT brain scan and a neurophysiological study (parietal EMG and/or PES). In addition, any toxic-metabolic cause that could be produced by this clinical phenomenon was ruled out with the appropriate testing. Unilateral asterixis is a clinical symptom that may indicate the presence of focal brain damage. Often, it is ignored or overlooked during routine neurological examinations. On the other hand, the presence of a bilateral asterixis is not always indicative of a toxic-metabolic encephalopathy.Rarely, such as in one of the cases herein presented, bilateral asterixis can also appear associated with structural brain lesions. Although asterixis diagnosis is fundamentally clinical, the neurophysiological study contributes to verify the diagnosis. 相似文献
90.
Expression and purification of functional recombinant epitopes for the platelet antigens, PlA1 and PlA2 总被引:1,自引:1,他引:1
The platelet antigens, PlA1 and PlA2, are responsible for most cases of posttransfusion purpura (PTP) and neonatal alloimmune thrombocytopenia (NAIT) in the caucasian population and are determined by two allelic forms of the platelet glycoprotein GPIIIa gene. To study the interaction between these antigens and their respective antibodies, we inserted the sequence that encodes the signal peptide and the N- terminal 66 amino acids of the PlA1 form of GPIIIa into the expression vector pGEX1. To express the PlA2 antigen, nucleotide 196 of the PlA1 coding sequence was mutated to the PlA2 allelic form. When transformed and induced in Escherichia coli, the two constructs produce glutathione S-transferase (GST)/N-terminal GPIIIa fusion proteins, one containing leucine at position 33 (PlA1), the other proline (PlA2). These proteins are easily purified in milligram quantities using glutathione-Sepharose and react specifically with their respective antibodies by immunoblot and enzyme-linked immunosorbent assay. Antigenicity of the PlA1 fusion protein in reduced glutathione increases with time; moreover, the addition of oxidized glutathione accelerates this process, presumably because of formation of the native disulfide bonds. Neutralization assays indicate that the PlA1 fusion protein competes for all of the anti-PlA1 antibody in the serum of patients with PTP and NAIT that is capable of interacting with the surface of intact platelets. This study shows that the GST/N-terminal GPIIIa fusion proteins contain conformational epitopes that mimic those involved in alloimmunization, and that regions other than the amino terminal 66 amino acids of GPIIIa are not likely to contain or be required for the development of functional PlA1 epitopes. Furthermore, these recombinant proteins can be used for the affinity-purification of clinical anti-PlA1 antibodies and specific antibody identification by western blotting, making them useful in the diagnosis of patients alloimmunized to PlA1 alloantigens. 相似文献