984 resultados para salivary immunoglobulin A


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An increasing amount of research has been conducted on immunoglobulin Y (IgY) because the use of IgY offers several advantages with respect to diagnostic testing, including its easy accessibility, low cost and translatability to large-scale production, in addition to the fact that it can be ethically produced. In a previous work, immunoglobulin was produced and purified from egg yolks (IgY) reactive to hepatitis A virus (HAV) antigens. In the present work, this anti-HAV-specific IgY was used in an indirect immunofluorescence assay to detect viral antigens in liver biopsies that were obtained from experimentally infected cynomolgus monkeys. Fields that were positive for HAV antigen were detected in liver sections using confocal microscopy. In conclusion, egg yolks from immunised hens may be a reliable source for antibody production, which can be employed for immunological studies.

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Leptospirosis is a zoonotic disease caused by pathogenic spirochetes of theLeptospira genus. Vaccination with bacterins has severe limitations. Here, we evaluated the N-terminal region of the leptospiral immunoglobulin-like B protein (LigBrep) as a vaccine candidate against leptospirosis using immunisation strategies based on DNA prime-protein boost, DNA vaccine, and subunit vaccine. Upon challenge with a virulent strain ofLeptospira interrogans, the prime-boost and DNA vaccine approaches induced significant protection in hamsters, as well as a specific IgG antibody response and sterilising immunity. Although vaccination with recombinant fragment of LigBrep also produced a strong antibody response, it was not immunoprotective. These results highlight the potential of LigBrep as a candidate antigen for an effective vaccine against leptospirosis and emphasise the use of the DNA prime-protein boost as an important strategy for vaccine development.

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Toxic epidermal necrolysis (TEN, Lyell's syndrome) is a severe adverse drug reaction in which keratinocytes die and large sections of epidermis separate from the dermis. Keratinocytes normally express the death receptor Fas (CD95); those from TEN patients were found to express lytically active Fas ligand (FasL). Antibodies present in pooled human intravenous immunoglobulins (IVIG) blocked Fas-mediated keratinocyte death in vitro. In a pilot study, 10 consecutive individuals with clinically and histologically confirmed TEN were treated with IVIG; disease progression was rapidly reversed and the outcome was favorable in all cases. Thus, Fas-FasL interactions are directly involved in the epidermal necrolysis of TEN, and IVIG may be an effective treatment.

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Monoclonal IgG are commonly observed in various B cell disorders, of which multiple myeloma is the most clinically relevant. In a series of serum samples, we identified by immunofixation 73 monoclonal IgG, including 63 IgG(1), 4 IgG(2), 5 IgG(3), and 1 IgG(4). The light chains were of kappa type in 45 cases, and of lambda type in 28 cases. These monoclonal IgG were further characterized by high resolution two-dimensional polyacrylamide gel electrophoresis (2-DE) in various isoelectric focusing conditions, as well as by 3-DE (2-DE of the proteins extracted from agarose after serum protein agarose electrophoresis). After 2-DE, 38 out of 73 monoclonal gamma chains (52%) were visualized using immobilized pH 3-10 gradients for isoelectric focusing. In 6 cases (8%), gamma chains were only detected using alkaline immobilized pH 6-11 gradients. In 3 cases (4%), 3-DE revealed monoclonal gamma chains hidden by polyclonal gamma chains. Finally, in 26 cases (36%), no monoclonal gamma chains were clearly visualized. Sixty-one monoclonal light chains (84%) were detected using immobilized pH 3-10 gradients, whereas 12 (16%) were not. Monoclonal gamma chains and light chains were highly heterogeneous in terms of pI and M(r). However, a statistically significant correlation (P<0.05) was observed between the position of the monoclonal IgG in agarose gel and the pI of their heavy and light chains (R=0.733, multiple linear regression). Because of the extreme diversity of their heavy and light chains, it appears that a classification of monoclonal IgG based only on their electrophoretic properties is not possible.

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A 46-year-old woman with a severe polyradiculoneuropathy treated with high-dose intravenous immunoglobulin (IVIg) presented an encephalopathy with increased blood flow velocities of the middle cerebral arteries (MCAs) detected by transcranial Doppler (TCD) studies. The similitude between this observation and another case recently reported of a patient suffering from Guillain-Barré syndrome (GBS) and cerebral blood flow abnormalities after IVIg treatment prompted us to investigate the responsibility of the IVIg therapy in the genesis of these blood flow alterations. We studied therefore by TCD 10 consecutive patients who underwent this treatment for different reasons. In 1 case we observed an asymptomatic, spontaneously reversible increase in the blood flow velocities of the MCAs consistent with a vasospasm and occurring 3-10 days after completion of the therapy. Stroke and ischemic encephalopathy have been reported as possible complications of IVIg treatment. In the case under discussion, clinical events appeared shortly after the administration of the IVIg therapy and responded favorably to a treatment with nimodipine. Other etiopathogenic mechanisms, in particular a CNS vasculopathic process related to the GBS itself, have to be considered as well. Further studies, with a larger number of patients, are therefore needed to evaluate the underlying mechanisms of blood flow abnormalities occurring sometimes in GBS patients after IVIg treatment.

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Rotavirus (RV)-specific secretory immunoglobulin (RV-SIg) has been previously detected in serum of naturally RV infected children and shown to reflect the intestinal Ig immune response. Total plasma SIgA and plasma RV-SIg were evaluated by ELISA in children with gastroenteritis due or not due to RV infection and in 50 children vaccinated with the attenuated RIX4414 human RV vaccine and 62 placebo recipients. RV-SIg was only detected in children with evidence of previous RV infection or with acute RV gastroenteritis. Vaccinees had higher RV-SIg titers than placebo recipients and RV-SIg titers increased after the second vaccine dose. RV-SIg measured after the second dose correlated with protection when vaccinees and placebo recipients were analyzed jointly. RV-SIg may serve as a valuable correlate of protection for RV vaccines.

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Résumé: Le traitement du cancer avancé de la tête et du cou nécessite souvent une approche multidisciplinaire associant la chirurgie, la radiothérapie et la chimiothérapie. Chacun de ces traitements présente des avantages, des limites et des inconvénients. En raison de la localisation de la tumeur primaire et/ou des métastases ganglionnaires, les glandes salivaires majeures sont fréquemment touchées par les traitements oncologiques. La salive joue un rôle déterminant dans la cavité buccale car elle lubrifie les tissus et facilite à la fois la déglutition et l'élocution. Son contenu en électrolytes et en protéines, dont certaines possèdent un effet antibactérien, protège les dents de la déminéralisation par l'acidité. Une fonction normale, liée autant à la quantité qu'à la qualité de la salive, reste indispensable pour le maintien d'une bonne santé buccale. L'objectif de cette étude prospective a été de déterminer, dans un groupe homogène de patients, l'influence d'un traitement de radiothérapie sur divers paramètres salivaires comme la sécrétion, le pH et l'effet tampon, avant, pendant et jusqu'à un an après la fin du traitement. L'étude a aussi examiné le comportement de ces paramètres salivaires après une intervention chirurgicale seule au niveau de la tête et du cou, avec ou sans exérèse d'une glande sous- maxillaire. L'étude s'est basée sur 54 patients (45 hommes et 9 femmes) atteints d'un carcinome épidermoïde avancé avec une localisation oro-pharyngée confirmée (n = 50) ou soupçonnée (n = 4), adressés et investigués dans le Centre Hospitalier Universitaire Vaudois de Lausanne, Suisse. Tous ces patients furent traités par radiothérapie seule ou en combinaison avec une chirurgie et/ou une chimiothérapie. Trente-neuf des 54 patients parvinrent à la fin de cette étude qui s'est étendue jusqu'à 12 mois au-delà de la radiothérapie. La chirurgie de la tête et cou, en particulier après ablation de la glande sous-maxillaire, a révélé un effet négatif sur la sécrétion salivaire. Elle n'influence en revanche ni le pH, ni l'effet tampon de la salive. Cependant, l'effet sur la sécrétion salivaire lié à la chirurgie est progressivement masqué par l'effet de la radiothérapie et n'est plus identifiable après 3-6 mois. Dès le début de la radiothérapie, la sécrétion salivaire chût très manifestement pour diminuer progressivement jusqu'à 1/3 de sa capacité à la fin du traitement actinique. Une année après la fin de cette radiothérapie, la dysfonction salivaire est caractérisée par une diminution moyenne de la sécrétion salivaire, de 93 % (p < 0,0001) pour la salive au repos et de 95 % (p < 0.0001) pour la salive stimulée, par rapport aux valeurs pré-thérapeutiques. Le pH salivaire ainsi que l'effet tampon furent également influencés par le traitement actinique. L'effet tampon a présenté une diminution à 67 % à une année post-traitement en comparaison de sa valeur pré-thérapeutique. Le pH de la salive stimulée présente une légère, mais significative, diminution par rapport à sa valeur antérieure à la radiothérapie. En conclusion, la chirurgie des cancers de l'oropharynx précédant une radiothérapie a une influence négative sur la sécrétion salivaire sans aggraver l'hyposialie consécutive aux radiations ionisantes. Cette étude confirme qu'un traitement oncologique comprenant une irradiation totale des glandes salivaires majeures chez des patients atteints d'un carcinome épidermoïde avancé de la région oro-pharyngée, induit une perte sévère et à long terme de la sécrétion salivaire avec une altération du pH et de l'effet tampon Abstract: Objective. We sought to investigate the impact of head and neck cancer treatment on salivary function. Study design. The study was conducted on 54 patients with advanced squamous cell carcinoma with confirmed (n =50) or suspected (n = 4) primary oropharyngeal localization who were treated with radiation alone or in combination with surgery or chemotherapy, or both. The following groups were considered in the evaluation: 1, the entire pool of patients; 2, those undergoing surgery and those not undergoing surgery before radiation; 3, those undergoing resection and those not undergoing resection of the submandibular gland. The flow rates, pH, and buffering capacity were determined before, during, and up to 12 months after the completion of radiation. Results. Head and neck surgery, particularly when submandibular gland resection was performed, had a negative impact on salivary flow rates but did not influence pH or buffering capacity. Nonetheless, the effect of surgery on salivary flow rates decreased progressively and disappeared at 3 to 6 months after radiotherapy. More than two thirds of the salivary output was lost during radiation treatment. All patients were experiencing salivary dysfunction at 1 year after completion of radiotherapy, with average decreases of 93% (P < .0001) and 95% (P < .0001) for whole resting salivary flow and whole stimulated salivary flow, respectively, compared with the preradiotherapy values. The buffering capacity decreased to 67% of its preradiotherapy value, and whole stimulated saliva became acidic. Conclusions. The result of this study confirms that cancer treatment involving full-dose radiotherapy (RTH) to all major salivary glands for locally advanced squamous cell carcinoma of the oropharynx induces severe hyposalivation with alteration of salivary pH and buffering capacity. Head and neck surgery has a negative impact on salivary flow rates, especially when the submandibular gland is removed. However, surgery before irradiation is not a factor aggravating hyposalivation when postoperative radiotherapy includes all the major salivary glands.

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The present study evaluates the use of salivary cortisol concentration as a physiological index of the stress level among nurses on their work day and day off and correlates it with the questionnaire used to measure occupational stress in nurses (Inventário de Estresse em Enfermeiros - IEE). This is a comparative, cross-sectional descriptive study in which sociodemographic data, IEE results and salivary cortisol levels were used. Fifty-seven nurses participated in the study (80.7% females and a mean age of 37.1 years old). The IEE average score was 124.5. The average cortisol level was 564.1 ng/m on work day and 354.1 ng/mL on day off. Nurses who had double workdays presented high values of salivary cortisol during the work day (638.1 ng/mL). In conclusion, salivary cortisol identified the nurses’ stress level, and differences were found between a work day and day off. On the nurses’ day off, their salivary cortisol levels and stress scores were lower.

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Laboratory studies were conducted to compare rostrum length morphology of mandible serration and area of food and salivary canals of Dichelops melacanthus (Dallas) (Dm), Euschistus heros (F.) (Eh), Nezara viridula (L.) (Nv), and Piezodorus guildinii (Westwood) (Pg) (Heteroptera: Pentatomidae). Nv showed the longest (5.9 mm) and Pg the shortest (3.5 mm) rostrum length; Dm and Eh were intermediate. Length and width of mandible tip areas holding serration was bigger for Nv (106.0 and 30.2 µm, respectively) and smaller for Pg (71.1 and 23.7 µm), with all species having four central teeth and three pairs of lateral teeth. The inner mandible surface showed squamous texture. Cross-section of food and salivary canals (Fc and Sc) indicated greater area for Nv and Dm compared to Eh and Pg; however, the ratio Fc/Sc, yielded the highest relative area for Pg.

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Human cytomegalovirus (CMV) infection may be a serious complication related to immunosuppression after solid organ transplantation. Due to their cytotoxicity, T-cells and natural killer (NK) cells target and clear the virus from CMV-infected cells. Although immunosuppressive drugs suppress T-cell proliferation and activation, they do not affect NK cells that are crucial for controlling the infection. The regulation of NK cells depends on a wide range of activating and inhibitory receptors such as the family of killer-cell immunoglobulin-like receptors (KIRs). Several human genetic studies have demonstrated the association of KIR genes with the clearance of infections. Since the respective activities of the different KIR proteins expressed by NK cells during CMV infection have not been extensively studied, we analyzed the expression of KIRs in a cohort of 22 CMV-IgG(+) renal transplant patients at the time of CMV reactivation, after antiviral therapy and 6 months later. Our data revealed a marked expression of KIR3DL1 during the acute phase of the reactivation. We set up an in vitro model in which NK cells, derived either from healthy donors or from transplanted patients, target allogeneic fibroblasts, CMV-infected or uninfected. Our results demonstrate a significant correlation between the lysis of CMV-infected fibroblasts and the expression of KIR3DL1. Blocking experiments with antibodies to MHC-I, to NKG2D and to NKG2C confirmed the importance of KIR3DL1. Consequently, our results suggest that KIR proteins and especially KIR3DL1 could play an important role during CMV-infection or CMV reactivation in immunosuppressed patients.

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Purpose: Involvement of salivary glands with mucosa-associated lymphoid tissue (MALT) lymphoma is rare. This retrospective study was performed to assess the clinical profile, treatment outcome, and prognostic factors of MALT lymphoma of the salivary glands.Methods and Materials: Thirteen member centers of the Rare Cancer Network from 10 countries participated, providing data on 63 patients. The median age was 58 years; 47 patients were female and 16 were male. The parotid glands were involved in 49 cases, submandibular in 15, and minor glands in 3. Multiple glands were involved in 9 patients. Staging was as follows: IE in 34, IIE in 12, IIIE in 2, and IV in 15 patients.Results: Surgery (S) alone was performed in 9, radiotherapy (RI) alone in 8, and chemotherapy (CT) alone in 4 patients. Forty-one patients received combined modality treatment (S + RT in 23, S + CT in 8, RT + CT in 4, and all three modalities in 6 patients). No active treatment was given in one case. After initial treatment there was no tumor in 57 patients and residual tumor in 5. Tumor progression was observed in 23 (36.5%) (local in 1, other salivary glands in 10, lymph nodes in 11, and elsewhere in 6). Five patients died of disease progression and the other 5 of other causes. The 5-year disease-free survival, disease-specific survival, and overall survival were 54.4%, 93.2%, and 81.7%, respectively. Factors influencing disease-free survival were use of RI, stage, and residual tumor (p < 0.01). Factors influencing disease-specific survival were stage, recurrence, and residual tumor (p < 0.01).Conclusions: To our knowledge, this report represents the largest series of MALT lymphomas of the salivary glands published to date. This disease may involve all salivary glands either initially or subsequently in 30% of patients. Recurrences may occur in up to 35% of patients at 5 years; however, survival is not affected. Radiotherapy is the only treatment modality that improves disease-free survival. (C) 2012 Elsevier Inc.

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Chlamydia serology is indicated to investigate etiology of miscarriage, infertility, pelvic inflammatory disease, and ectopic pregnancy. Here, we assessed the reliability of a new automated-multiplex immunofluorescence assay (InoDiag test) to detect specific anti-C. trachomatis immunoglobulin G. Considering immunofluorescence assay (IF) as gold standard, InoDiag tests exhibited similar sensitivities (65.5%) but better specificities (95.1%-98%) than enzyme-linked immunosorbent assays (ELISAs). InoDiag tests demonstrated similar or lower cross-reactivity rates when compared to ELISA or IF.