988 resultados para PRIMARY ANTIBODY DEFICIENCY
Resumo:
Treponema pallidum PCR (Tp-PCR) has been noted as a valid method for diagnosing syphilis. We compared Tp-PCR to a combination of darkfield microscopy (DFM), the reference method, and serologic testing in a cohort of 273 patients from France and Switzerland and found the diagnostic accuracy of Tp-PCR was higher than that for DFM.
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The WHO criterion of defering any donation of blood by a confirmed case of malaria for three years after cessation of therapy can not be applied in areas where malaria in endemic. For this reason we developed an immunoenzymatic assay for the detection of plasmodial antigens for blood screening in malararial endemic areas. So, we tested sera from 191 individuals. Among patients with active disease 100% of the cases of Plasmodium falciparum or mixed infections and 91.7% of those with P. vivax were positive for the presence of plasmodial antigens. The lower parasitaemia detected was 0.0003% for P. vivax malária. When the frequency of positive circulating malarial antigens was evaluated among asymptomatic and symptomatic individuals with negative TBS, positive results were found in respectively 38.7% and 17.7% of the individuals studied in the 30 days after confirmed malaria attack. Data provide by these assays have shown that ELISA seemed to be more sensitive than parasitological examination for malaria diagnosis. This test by virtue of its high sensivity and the facilities in processing a large number of specimens, can prove to be useful in endemic areas for the recognition of asymptomatic malaria and screening of blood donors.
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In view of the recent demonstration that antibodies that are protective agains Plasmodium falciparum malaria may act in collaboration with blood monocytes, we have investigated the isotype content of sera from individuals with defined clinical states of resistance or susceptibility to malaria. Profound differences in the distribution of each Ig subclass and particulary in the ratio of cytophilic versus noncytophilic antibodies were found. In protected subjects, two cytophilic isotypes, IgG1 and IgG3 were found to predominate. In non-protected subjects, i.e. children and primary attack adults, three different situations were encountered: a) an imbalance in which IgG2, a non-cytophilic class, predominated (mostly seen in primary attacks); b) imbalance in which mostly IgM antibodies predominated (a frequent event in children) or c) less frequently, an overall low level of antimalarial antibodies. Of 33 non immune subjects studied all, except one, had one of the above defects. The function of total Ig presenting such an isotype imbalance was studied in vitro in Antibody-Dependent -Cellular-Inhibition assays. Not only did IgG from protected subjects cooperate efficiently with blood monocytes, whilst IgG from non-protected groups did not, but moreover the latter inhibit the in vitro effect of the former: in competition assays whole IgG from primary attack cases with increased IgG2 content, competed with IgG from immune adults, thus suggesting that non-protected subjects had antibodies to epitopes critical for protection, but that these antibodies are non functional.
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A procedure was devised for the identification and specific cloning of functionally rearranged variable region immunoglobulin (Ig) gene segments from genomic DNA of a murine hybridoma cell line which produces a high-affinity monoclonal antibody (MAb) directed against human carcinoembryonic antigen (CEA). The cloned, functionally-rearranged murine Ig H-chain and L-chain variable region gene segments were incorporated into plasmid vectors capable of directing the expression of a chimaeric mouse-human antibody molecule with human (gamma 4, kappa) constant region sequences. Expression plasmids were transfected into a mouse myeloma cell line by electroporation and transfectomas secreting functional chimaeric antibody selected. Chimaeric antibody generated by transfectomas was analysed and shown to compete effectively with its murine counterpart for binding to the CEA epitope, and to have an equivalent antigen-binding affinity. This anti-CEA recombinant antibody should find application in in vivo diagnosis by immunoscintigraphy of human colonic carcinoma, and possibly also in therapy of the disease, overcoming some of the difficulties associated with the repeated use of non-human immunoglobulins in human patients.
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La dépression majeure est fréquente chez les patients qui consultent un cabinet de médecine générale. Elle reste toutefois difficile à diagnostiquer car elle est souvent masquée par une ou plusieurs plaintes physiques qui sont l'unique motif de consultation. Pour aider le médecin généraliste à démasquer ce trouble, un test de dépistage composé de deux questions a été développé et validé. Ce test indique une probabilité accrue de dépression si le patient répond positivement à au moins une des deux questions suivantes : « Est-ce que, durant le mois qui a précédé, vous vous êtes senti(e) triste, déprimé(e), désespéré(e) ? » et « Durant le mois qui a précédé, avez-vous ressenti un manque d'intérêt et de plaisir dans la plupart des activités que d'habitude vous appréciez ? ». Une troisième question, ajoutée aux deux questions ci-dessus, a été proposée récemment afin d'améliorer les performances de ce test de dépistage. Cette troisième question rend le test négatif si le patient répond négativement à la question suivante : « Souhaitez-vous de l'aide pour cela ? ». Une étude avait indiqué que l'ajout de la question supplémentaire améliorait la spécificité du test sans réduire sa sensibilité. Objectifs Il s'agissait de décrire la performance de deux tests de dépistage de la dépression majeure, composés, respectivement, de deux et de trois questions, dans une population de patients consultant dans un cabinet de médecine générale pour une plainte physique, et de les valider. Méthode Les réponses aux questions des tests de dépistage de la dépression dans la population de la cohorte SODA (Somatisation, Depression, Anxiety) ont été utilisées. Il s'agissait de patients de plus de 18 ans, sélectionnés aléatoirement, consultant pour au moins une plainte physique auprès de 24 médecins généralistes de Suisse Romande, réexaminés une année après l'inclusion dans la cohorte. Le questionnaire validé « Full Patient Health Questionnaire » a été utilisé, le même jour, pour diagnostiquer une dépression majeure. Ce résultat a été utilisé pour évaluer les performances des deux tests de dépistage en calculant la sensibilité et la spécificité, notamment. Résultats Les données de 724 / 937 patients inclus ont pu être utilisées. Un diagnostic de dépression majeure a été posé chez 9.5% des patients (n = 69). La sensibilité et la spécificité des deux questions de dépistage étaient de 91.3% (IC95% : 81.4-96.4%) et 65.0% (IC95% : 61.2-68.6%), respectivement. En ajoutant la troisième question, la sensibilité des deux questions de dépistage a diminué à 59.4% (IC95% : 47.0-70.9%) et la spécificité a augmenté à 88.2% (IC95% : 85.4-90.5%). Conclusions L'utilisation des deux questions pour le dépistage de la dépression majeure est associée à une haute sensibilité et à une basse spécificité chez des patients se présentant en cabinet de médecine générale pour une plainte physique. En ajoutant la troisième question, la spécificité augmente, mais la sensibilité diminue. Ainsi, en ajoutant la troisième question, quatre patients dépressifs majeurs sur dix ne sont pas détectés, alors que seulement un patient sur dix n'est pas détecté avec les deux questions de dépistage. Notre étude montre que le test composé de deux questions reste une méthode de choix pour le dépistage de la dépression majeure et que l'ajout de la troisième question n'est pas recommandée. Celle-ci reste toutefois pertinente dans l'incitation au dialogue sur le sujet de la dépression entre le médecin et son patient.
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PURPOSE: The purpose of this study was to characterize local distribution and systemic absorption of the tumor necrosis factor (TNF)-alpha inhibitory single-chain antibody fragment (scFv) ESBA105 following topical administration to the eye in vivo. METHODS: Rabbits received ESBA105 as topical eye drops in two dosing regimens. First, pharmacokinetics after the topical route of administration was compared to the intravenous (i.v.) route by means of applying the identical cumulative daily dose of ESBA105. In a second study rabbits received five eye drops daily for six consecutive days in a lower frequency topical dosing regimen. Kinetics and biodistribution of ESBA105 in ocular tissues and fluids as well as in sera were determined in all animals. RESULTS: After topical administration to the eye, ESBA105 quickly reaches therapeutic concentrations in all ocular compartments. Systemic exposure after topical administration is 25,000-fold lower than exposure after i.v. injection of the identical cumulative daily dose. ESBA105 levels in vitreous humor and neuroretina are significantly higher on topical administration than after i.v. injection. Absolute and relative intraocular biodistribution of ESBA105 is different with topical and systemic delivery routes. Compared to its terminal half-life in circulation (7 hours), the vitreal half-life of ESBA105 is significantly enhanced (16-24 hours). CONCLUSIONS: On topical administration, ESBA105 is efficiently absorbed and distributed to all compartments of the eye, whereby systemic drug exposure is very low. Based on its unique intraocular biodistribution and pharmacokinetics and the absolute intraocular levels reached, topical ESBA105 appears highly attractive for treatment of various ophthalmological disorders.
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The cytokine macrophage migration inhibitory factor (MIF) is an important component of the early proinflammatory response of the innate immune system. However, the antimicrobial defense mechanisms mediated by MIF remain fairly mysterious. In the present study, we examined whether MIF controls bacterial uptake and clearance by professional phagocytes, using wild-type and MIF-deficient macrophages. MIF deficiency did not affect bacterial phagocytosis, but it strongly impaired the killing of gram-negative bacteria by macrophages and host defenses against gram-negative bacterial infection, as shown by increased mortality in a Klebsiella pneumonia model. Consistent with MIF's regulatory role of Toll-like 4 expression in macrophages, MIF-deficient cells stimulated with lipopolysaccharide or Escherichia coli exhibited reduced nuclear factor κB activity and tumor necrosis factor (TNF) production. Addition of recombinant MIF or TNF corrected the killing defect of MIF-deficient macrophages. Together, these data show that MIF is a key mediator of host responses against gram-negative bacteria, acting in part via a modulation of bacterial killing by macrophages.
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Lactate is increasingly described as an energy substrate of the brain. Beside this still debated metabolic role, lactate may have other effects on brain cells. Here, we describe lactate as a neuromodulator, able to influence the activity of cortical neurons. Neuronal excitability of mouse primary neurons was monitored by calcium imaging. When applied in conjunction with glucose, lactate induced a decrease in the spontaneous calcium spiking frequency of neurons. The effect was reversible and concentration dependent (IC50 ∼4.2 mM). To test whether lactate effects are dependent on energy metabolism, we applied the closely related substrate pyruvate (5 mM) or switched to different glucose concentrations (0.5 or 10 mM). None of these conditions reproduced the effect of lactate. Recently, a Gi protein-coupled receptor for lactate called HCA1 has been introduced. To test if this receptor is implicated in the observed lactate sensitivity, we incubated cells with pertussis toxin (PTX) an inhibitor of Gi-protein. PTX prevented the decrease of neuronal activity by L-lactate. Moreover 3,5-dyhydroxybenzoic acid, a specific agonist of the HCA1 receptor, mimicked the action of lactate. This study indicates that lactate operates a negative feedback on neuronal activity by a receptor-mediated mechanism, independent from its intracellular metabolism.
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Background: In recent years, an increasing number of auto-antibodies (AB) have been detected in the CSF and serum of patients with new onset epilepsy. Some of these patients develop convulsive or nonconvulsive status epilepticus (AB-SE), necessitating intensive medical care and administration of multiple antiepileptic and immunomodulatory treatments of uncertain effectiveness. Objectives: In this retrospective multicenter survey we aimed to determine the spectrum of gravity, the duration and the prognosis of the disorder. In addition, we sought to identify the antibodies associated with this condition, as well as determine whether there is a most effective treatment regime. Methods: 12 European Neurology University Clinics, with extensive experience in the treatment of SE patients, were sent a detailed questionnaire regarding symptoms and treatment of AB-SE patients. Seven centers responded positively, providing a total of 13 patients above the age of 16. Results: AB-SE affects mainly women (12/13, 92%) with a variable age at onset (17-69 years, median: 25 years). The duration of the disease is also variable (10 days to 12 years, median: 2 months). Only the 3 oldest patients died (55-69 years). Most patients were diagnosed with anti NMDAR encephalitis (8/13) and had oligoclonal bands in the CSF (9/13). No specific treatment regimen (antiepileptic, immunomodulatory) was found to be clearly superior. Most of the surviving 10 patients (77%) recovered completely or nearly so within 2 years of index poststatus. Conclusion: AB-SE is a severe but potentially reversible condition. Long duration does not seem to imply fatal outcome; however, age older than 50 years at time of onset appears to be a risk factor for death. There was no evidence for an optimal antiepileptic or immunomodulatory treatment. A prospective multicenter study is warranted in order to stratify the optimal treatment algorithm, determine clear risk factors of unfavorable outcome and long-term prognosis.
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AIMS: Patients with well-tolerated sustained monomorphic ventricular tachycardia (SMVT) and left ventricular ejection fraction (LVEF) over 30% may benefit from a primary strategy of VT ablation without immediate need for a 'back-up' implantable cardioverter-defibrillator (ICD). METHODS AND RESULTS: One hundred and sixty-six patients with structural heart disease (SHD), LVEF over 30%, and well-tolerated SMVT (no syncope) underwent primary radiofrequency ablation without ICD implantation at eight European centres. There were 139 men (84%) with mean age 62 ± 15 years and mean LVEF of 50 ± 10%. Fifty-five percent had ischaemic heart disease, 19% non-ischaemic cardiomyopathy, and 12% arrhythmogenic right ventricular cardiomyopathy. Three hundred seventy-eight similar patients were implanted with an ICD during the same period and serve as a control group. All-cause mortality was 12% (20 patients) over a mean follow-up of 32 ± 27 months. Eight patients (40%) died from non-cardiovascular causes, 8 (40%) died from non-arrhythmic cardiovascular causes, and 4 (20%) died suddenly (SD) (2.4% of the population). All-cause mortality in the control group was 12%. Twenty-seven patients (16%) had a non-fatal recurrence at a median time of 5 months, while 20 patients (12%) required an ICD, of whom 4 died (20%). CONCLUSION: Patients with well-tolerated SMVT, SHD, and LVEF > 30% undergoing primary VT ablation without a back-up ICD had a very low rate of arrhythmic death and recurrences were generally non-fatal. These data would support a randomized clinical trial comparing this approach with others incorporating implantation of an ICD as a primary strategy.
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Background¦The outcome after primary percutaneous coronary intervention (pPCI) for STElevation¦Myocardial Infarction (STEMI) is strongly affected by time delays. In thepresent study, we sought to identify the impact of specific socioeconomic factors on time delays, subsequent STEMI management and outcomes in STEMI patients from a well-defined region of the French part of Switzerland.¦Method¦A total of 402 consecutive patients undergoing pPCI for STEMI in a large tertiary hospital were retrospectively studied. Symptom-to-first-medical-contact time was analyzed for the following socioeconomic factors: level of education, gender, origin and marital status. Main exclusion criteria were: time delay beyond 12 hours, previous treatment by fibrinolysis or patients immediately referred for CABG.¦Therefore, 352 patients were finally included.¦Results¦At one year, there was no difference in mortality amongst the different socioeconomic groups. Furthermore, there was no difference in management characteristics between them. Symptom-to-first-medical-contact time was significantly higher for patients with a low level of education, Swiss citizens and non-married patients with median differences of 40 minutes, 48 minutes, and 60 minutes, respectively (p<0.05).¦Nevertheless, no difference was found regarding in-hospital management and clinical outcome.¦Conclusion¦This study demonstrates that symptom-to-first-medical-contact time is higher amongst people with a lower educational level, Swiss-citizens, and non-married people. Because of the low mortality rate in general, these differences in time delays did not affect clinical outcomes. Still, primary prevention measures should particularly focus on these vulnerable populations.
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Selection III mice have particular immunological characteristics: they are high (H III) or low (L III) antibody producer animals, yet both lines display similar T cell responses and macrophage activities. We submittedthese mice to infection with Schistosoma mansoni to assess in vivo parasite and egg burden, hepatic collagen and cellular composition of granulomas in both lines. Titration of anti-Schistosoma IgG by ELISA showed remarkably higher values inH III line, at both studied periods (8th and 12th weeks post-infection). Nevertheless, the number of adult worms recovered from the portal system was similar inboth lines, being not associated with anti-Schistosoma antibody levels. There isan increase in hepatic collagen from the 8th to the 12th weeks post-infection, which is paralleled by an increase in the number of eggs in the liver. This association apparently occurs at the same radio in H III and L III animals. The most important difference found between the two lines was the outstanding contrast interms of volume and eosinophil counts in the granulomas, with lesions from H IIImice clearly being larger and containing more of these cells than LIII lesions.
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BACKGROUND: Efforts to decrease overuse of health care may result in underuse. Overuse and underuse of colonoscopy have never been simultaneously evaluated in the same patient population. METHODS: In this prospective observational study, the appropriateness and necessity of referral for colonoscopy were evaluated by using explicit criteria developed by a standardized expert panel method. Inappropriate referrals constituted overuse. Patients with necessary colonoscopy indications who were not referred constituted underuse. Consecutive ambulatory patients with lower gastrointestinal (GI) symptoms from 22 general practices in Switzerland, a country with ready access to colonoscopy, were enrolled during a 4-week period. Follow-up data were obtained at 3 months for patients who did not undergo a necessary colonoscopy. RESULTS: Eight thousand seven hundred sixty patient visits were screened for inclusion; 651 patients (7.4%) had lower GI symptoms (mean age 56.4 years, 68% women). Of these, 78 (12%) were referred for colonoscopy. Indications for colonoscopy in 11 patients (14% of colonoscopy referrals or 1.7% of all patients with lower GI symptoms) were judged inappropriate. Among 573 patients not referred for the procedure, underuse ranged between 11% and 28% of all patients with lower GI symptoms, depending on the criteria used. CONCLUSIONS: Applying criteria from an expert panel of nationally recognized experts indicates that underuse of referral for colonoscopy exceeds overuse in primary care in Switzerland. To improve quality of care, both overuse and underuse of important procedures must be addressed.