956 resultados para sperm antibody


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Maternal antibody (MatAb) transfer is important for early chicken survivability. Diet composition and the amount of feed given to breeder pullets during rearing may affect the development of immunity and the transfer of MatAb to progeny, and could affect progeny performance and resistance to disease. The effects of broiler breeder nutrition and feeding management practices were evaluated for the transfer of MatAb to progeny and for spleen and bursa development at hatching in 2 genetic strains (A and B). In this experiment, the levels of MatAb against Newcastle disease virus were assessed by enzyme-linked immunosorbent assays in serum samples taken of pedigreed chicken progeny from hatching to 13 d of age. Chickens were fed corn-and wheat-based diets, as were their parents. The breeder feeding program and diet type altered the Newcastle disease virus MatAb found in progeny at hatching and affected how long these antibodies were maintained in circulation. Bursal follicle size at hatching was influenced by an interaction among all factors evaluated. Percentage of white pulp in the spleen was affected mainly by genetic strain and diet type, but responses varied according to the breeder feeding program. It was concluded that breeder feeding programs influence MatAb transfer and half-life, and may also affect the early development of lymphoid tissues.

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C-reactive protein (CRP) is an acute phase protein whose levels are increased in many disorders. Levels greater than 3 mu g/mL serum have hitherto been considered to indicate pathology, but there is increasing interest in assessments between 0.1 and 10 mu g/mL, which have been found to correlate with severity of risk for cardiovascular disease. We report herein the generation of both antibody and Affimer based impedance immunoassays for CRP that are substantially more sensitive than clinically utilized immunonephelometry and immunoturbidity assessments. Significant in this study is not only the use of a constrained peptide to detect a clinically important target but also that derived electrochemical impedance assays can be highly sensitive even with probes whose relatively weak (mu M) affinities are not amenable to target detection by surface plasmon resonance (SPR). Key to this finding is acknowledging that receptive surfaces of comparatively low initial steric bulk and charge transfer resistance are especially primed to be highly responsive to target binding in electroanalytical assays of this type.

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The present study aimed to compare testicular histology and the testicular cell population as well as spermatogenic efficiency in goats with different scrotal conformations. Eighteen goats were divided into 3 groups: Group I - goats without bipartition of the scrotum, Group II - animals with bipartition of the scrotum up to 50% of the testicular length, Group III - goats with scrotal bipartition more than 50% of the testicular length. In goats in Groups I, II and III, the values for the volume density of seminiferous epithelium were 68.9 +/- 0.6%, 71.5 +/- 2.8% and 73.4 +/- 4.7% (P < 0.05), the height of the seminiferous epithelium were 60.2 +/- 4.9 mu m, 61.0 +/- 5.0 mu m and 73.1 +/- 6.6 mu m (P < 0.05), total length of seminiferous tubules found for Groups I, II and III were 2091.9 +/- 27 m, 2172.5 +/- 24.1 m, and 2340.1 14 m (P < 0.05), number of Sertoli and Leydig cells were 1.8 +/- 0.4 x 10(9) and 1.4 +/- 0.1 x 10(9), 2.2 +/- 0.4 and 2.2 +/- 0.7 x 10(9), and 2.5 +/- 0.1 10(9) and 2.3 +/- 0.510(9)(P < 0.05)and daily sperm production observed were 2.1 0.3 x 109, 2.8 0.4 x 109, and 3.1 0.7 x 109 (P < 0.05). In conclusion, goats with greater scrotal bipartition have a greater capacity to produce reproductive cells that is reflected in a greater reproductive potential. (C) 2011 Elsevier B.V. All rights reserved.

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During spermiogenesis, the spermatids of the pimelodid species Pimelodus maculatus and Pseudoplatystoma fasciatum show a central flagellum development, no rotation of the nucleus, and no nuclear fossa formation, in contrast to all previously described spermatids of Teleostei. These characteristics are interpreted as belonging to a new type of spermiogenesis, named here type III, which is peculiar to the family Pimelodidae. In P. maculatus and P. fasciatum, spermatozoa possess a spherical head and no acrosome; their nucleus contains highly condensed, homogeneous chromatin with small electron-lucent areas; and a nuclear fossa is not present. The centriolar complex lies close to the nucleus. The midpiece is small, has no true cytoplasmic channel, and contains many elongate and interconnected vesicles. Several spherical to oblong mitochondria are located around the centriolar complex. The flagellum displays the classical axoneme (9 + 2) and no lateral fins. Only minor differences were observed among the pimelodid species and genera. Otherwise, spermiogenesis and spermatozoa in the two species of Pimelodidae studied exhibit many characteristics that are not found in other siluriform families, mainly the type III spermiogenesis. (C) 2007 Elsevier GmbH. All rights reserved.

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The spin label TEMPO does not show a binding to myoglobin molecule in solution. This is probably due to the fact that this protein does not have a hydrophobic pocket large enough to accommodate the TEMPO molecule. In the crystal the spin label is bound and two kinds of spectra are observed: one isotropic and the other anisotropic. The anisotropic site is probably an intermolecular one. The correlation time for the label in the crystal is very sensitive to temperature showing a transition near 30 °C. This change can be explained as a result of the conformational change observed for myoglobin near this temperature: the motion of the spin label becomes more restricted below this temperature. Change in hydration is the probable cause of this structural change. The changes in the EPR spectra of the anisotropic label suggest that it is bound near the first layers of protein in the crystal. © 1985 Societá Italiana di Fisica.

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The three larval stages of Dermatobia hominis (Linnaeus) have been evaluated for their immunogenicity by ELISA and immunodiffusion (ID) using sera from experimentally infested rabbits. During a primary infestation, first instar D. hominis were found to cause most reaction and allowed the earliest diagnosis by ELISA. An inhibition of the antibody response against second and third instars was observed. The inhibition disappeared after departure of the larvae from the host. In experimentally immunized hosts the antibody response, following challenge, was highest against second and third instar antigens. Antibody remained elevated during the infestation but fell immediately after the larvae had left the host.

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Sera of patients with paracoccidioidomycosis contained IgG-, IgA-, and IgM-specific antibodies to a 43 kDa antigen contained in the filtrate of a culture of Paracoccidioides brasiliensis. IgG- and IgA-specific antibodies were present in all observed patients. The IgM response was more frequent in acute cases, and the mean titers of IgG- and IgM-specific antibodies were higher in the acute forms. By the fourth month of chemotherapy, there was a decay of IgG, IgA, and IgM antibody titers to this antigen in acute cases, correlating with clinical improvement. The detection of IgG and IgA antibodies and the sequential determination of antibodies to the 43 kDa glycoprotein may be useful tools for serodiagnosis and evaluation of therapeutic efficacy.

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A simple and sensitive chemiluminescence assay for the demonstration of the activity of intracellular myeloperoxidase (MPO) is described, which is useful for the distinction between myeloid and lymphoid commitment in blasts from acute leukemia patients. When the cut-off point was settled at 13 mV of chemiluminescence all cases of acute myeloid leukemia (AML) were distinguished from those of acute lymphoid leukemia. In addition, this technique was able to demonstrate MPO activity in AML poorly differentiated (FAB-M0) which usually does not stain for MPO in classical cytochemistry preparations and could be negative also by immunocytochemistry with anti-MPO monoclonal antibody. Therefore the method here described presented a higher sensitivity than the immunocytochemistry procedure with anti-MPO.

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Adhesion is regarded as an important step in the pathogenesis of several microorganisms. Thus, the ability to recognize extracellular matrix proteins, such as laminin or fibronectin, has been correlated with invasiveness. Studying the already characterized laminin-binding protein of Paracoccidioides brasiliensis, the 43 kDa glycoprotein (gp43), we evaluated whether MAb 1.H12, raised against the laminin-binding protein from Staphylococcus aureus, cross-reacts with that fungal protein. By immunoblot analysis we show that MAb 1.H12 recognizes gp43. This interaction is able to inhibit the laminin-mediated adhesion to epithelial cells as well as the P. brasiliensis infection in vivo. Moreover, through immunoenzymatic assays, we show that MAb 1.H12 recognizes gp43 in solid phase and that this interaction is partially inhibited by the addition of anti-gp43 MAbs. These results show that MAb 1.H12 recognizes the gp43, suggesting the presence of an epitope similar to those found in the other laminin-binding proteins from phylogenetically very distant cells. These findings reinforce the possibility of evolutionary conservation of such epitopes.

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IgG, IgM and IgA antibodies to GP43 (glycoprotein fraction of Paracoccidioides brasiliensis) were measured by ELISA in 63 samples from 23 patients with paracoccidioidomycosis before and twice after chemotherapy was started. Antibodies against P. brasiliensis were detected by indirect immunofluorescence (IF) (IgG, IgM and IgA isotypes), counterimmunoelectrophoresis (CIE) and complement fixation. Two control groups composed of 19 healthy individuals and 12 patients with other diseases (six with histoplasmosis, three with tuberculosis and three with other mycoses). The highest efficiency percentages were found with IgG and IgA- ELISA (100%), IgG-IF (96.2%), CIE (94.4%) and the lowest with CF (75.9%). Highest positive and negative predictive values (100%) were observed for IgG and IgA ELISA. IgG and IgM-ELISA antibodies are more often found in patients with acute than chronic disease (P = 0.01). Four to six months after treatment follow-up showed decreased levels of IgG and IgM-ELISA for acute cases and decreased titres of CIE for chronic cases in relation to pretreatment levels. This study suggests that IgG-ELISA anti-GP43 represents a good marker to monitor clinical response to therapy.