Effect of Plastic Deformation on the Excess Loss of Electrical Steel

The interpretation of the effect of plastic deformation on the calculated excess loss component (anomalous-loss) supports the concept of loss separation. Magnetic losses and Barkhausen noise of nonoriented electrical steel sheets were measured on Epstein strips taken from a single coil of 0.8% Si nonoriented electrical steel. Sheets were extracted in the annealed condition, without any skin pass and with a grain size of 18 mu m. This material was cold rolled in order to obtain sets of samples with true strain from 2% up to 29%. X-ray diffraction was used to estimate the dislocation density. The analysis of magnetic properties was performed by Barkhausen noise measurements and also by analyzing the hysteresis loops obtained from Epstein frame measurements for different inductions and different frequencies (including the quasi-static regime for hysteresis loss measurements). These data allowed us to observe that most of the well known total loss increase with plastic deformation is due to an increase in the hysteresis loss component, while excess loss decreases to become negligible. This behavior can be explained if it is assumed that the plastic deformation lead to an increase in the number of domain walls per unit volume, thereby decreasing the excess loss. Barkhausen peak area increases with plastic deformation, reproducing results taken from samples of different silicon content.

Oxidized low-density lipoproteins and their antibodies: Relationships with the reverse cholesterol transport and carotid atherosclerosis in adults without cardiovascular diseases

Background: Metabolic predictors and the atherogenicity of oxidized LDL (oxLDL) and the specific antibodies against oxLDL (oxLDL Ab) are unclear and controversial. Methods: In 107 adults without atherosclerotic manifestations, we measured oxLDL and oxLDL Ab, and also the activities of CETP. PLTP, lipases and the carotid intima-media thickness (cIMT). Comparisons were performed for the studied parameters between the lowest and the highest tertile of oxLDL and oxLDL Ab, and the relationships between studied variables were evaluated. Results: Subjects with higher oxLDL Ab present reduced hepatic lipase activity and borderline increased cIMT. In the highest oxLDL tertile, besides the higher levels of total cholesterol, LDL-C and apoB100, we found reduced CETP activity and higher cIMT. A significant correlation between oxLDL Ab and cIMT, independent of oxLDL, and a borderline correlation between oxLDL and cIMT independent of oxLDL Ab were found. In the multivariate analysis, apoAl was a significant predictor of oxLDL Ab, in contrast to regulation of oxLDL by apoB100, PLTP and inverse of CETP. Conclusions: In adults without atherosclerotic disease, the metabolic regulation and carotid atherosclerosis of oxLDLAb and oxLDL groups, characterized a dual trait in oxLDL Ab, as a contributor to carotid atherosclerosis, much less so than oxidized LDL, and with a modest atheroprotective role. (C) 2012 Elsevier B.V. All rights reserved.

OCCURRENCE OF ANTIBODIES TO TOXOPLASMA GONDII AND LEPSTOSPIRA SPP. IN MANATEES (TRICHECHUS INUNGUIS) OF THE BRAZILIAN AMAZON

The presence of Toxoplasma gondii and Leptospira spp. antibodies was investigated in 74 manatees (Trichechus inunguis [Mammalia: Sirenia]) kept in captivity in two rescue units in the northern region of Brazil. Antibodies to T gondii were detected in 29 (39.2%) of 74 animals by using the modified agglutination test (titer, 1:25). For antibodies against Leptospira spp., sera were diluted 1:50 and tested against 24 strains of leptospires by microscopic agglutination microtechnique, and positive samples were end titrated. Twenty-three (31.1%) of 74 animals were reactive to four serovars (Patoc 21/23, Castellonis 2/23, Icterohaemorrhagiae 1/23, and Butembo 1/23), with titers ranging from 100 to 1,600. This is the first report of antibodies against T gondii and Leptospira spp. in T. inunguis from the Brazilian Amazon.

Cross-reactivity of antipneumococcal surface protein C (PspC) antibodies with different strains and evaluation of inhibition of human complement factor H and secretory IgA binding via PspC

Pneumococcal surface protein C (PspC) is an important candidate for a cost-effective vaccine with broad coverage against pneumococcal diseases. Previous studies have shown that Streptococcus pneumoniae is able to bind to both human factor H (FH), an inhibitor of complement alternative pathway, and human secretory IgA (sIgA) via PspC. PspC was classified into 11 groups based on variations of the gene. In this work, we used three PspC fragments from different groups (PspC3, PspC5, and PspC8) to immunize mice for the production of antibodies. Immunization with PspC3 induced antibodies that recognized the majority of the clinical isolates as analyzed by Western blotting of whole-cell extracts and flow cytometry of intact bacteria, while anti-PspC5 antibodies showed cross-reactivity with the paralogue pneumococcal surface protein A (PspA), and anti-PspC8 antibodies reacted only with the PspC8-expressing strain. Most of the isolates tested showed strong binding to FH and weaker interaction with sIgA. Preincubation with anti-PspC3 and anti-PspC5 IgG led to some inhibition of binding of FH, and preincubation with anti-PspC3 partially inhibited sIgA binding in Western blotting. The analysis of intact bacteria through flow cytometry showed only a small decrease in FH binding after incubation of strain D39 with anti-PspC3 IgG, and one clinical isolate showed inhibition of sIgA binding by anti-PspC3 IgG. We conclude that although anti-PspC3 antibodies were able to recognize PspC variants from the majority of the strains tested, partial inhibition of FH and sIgA binding through anti-PspC3 antibodies in vitro could be observed for only a restricted number of isolates.

Prevalence of Anti-Neospora caninum and Anti-Toxoplasma gondii Antibodies in Dogs From Two Different Indigenous Communities in the Brazilian Amazon Region

Prevalence of Toxoplasma gondii and Neospora caninum antibodies in sera of 325 dogs in 11 villages inhabited by the Tapirape and Karaja ethnic groups in the south of the Brazilian Amazon was determined by the use of an indirect fluorescence antibody test. Antibodies (cutoff 1:16) to T. gondii were found in 169 (52%) and to N. caninum (cutoff 1:50) in 32 (9.8%) of 325 dogs. Seropositivity for both parasitic infections was widely prevalent in dogs from these villages and was higher in older dogs, indicating post-natal transmission.

Role of Neutralizing Antibodies in Adults With Community-Acquired Pneumonia by Respiratory Syncytial Virus

Background. Respiratory syncytial virus (RSV) has been implicated in the etiology of adult community-acquired pneumonia (CAP). We investigated RSV infection in Chilean adults with CAP using direct viral detection, real-time reverse-transcription polymerase chain reaction (rtRT-PCR), and serology (microneutralization assay). Methods. RSV, other respiratory viruses, and bacteria were studied by conventional and molecular techniques in adults aged >= 18 years presenting with CAP to the healthcare facilities in Santiago, Chile from February 2005 through December 2007. Results. All 356 adults with CAP enrolled had an acute blood sample collected at enrollment, and 184 had a convalescent blood sample. RSV was detected in 48 cases (13.4%). Immunofluorescence assay and viral isolation each detected only 1 infection (0.2%), whereas rtRT-PCR was positive in 32 (8.9%) cases and serology was positive in 20 (10.8%) cases. CAP clinical characteristics were similar in RSV-infected and non-RSV-infected cases. RSV-specific geometric mean serum-neutralizing antibody titer (GMST) was significantly lower at admission in the 48 RSV-infected cases compared with 308 non-RSV-infected adults (GMST in log(2): RSV/A 8.1 vs 8.9, and RSV/B 9.3 vs 10.4; P < .02). Conclusions. RSV infection is frequent in Chilean adults with CAP. Microneutralization assay was as sensitive as rtRT-PCR in detecting RSV infection and is a good adjunct assay for diagnostic research. High RSV-specific serum-neutralizing antibody levels were associated with protection against common and severe infection. The development of a vaccine could prevent RSV-related CAP in adults.

A serological follow-up of toxocariasis patients after chemotherapy based on the detection of IgG, IgA, and IgE antibodies by enzyme-linked immunosorbent assay.

A serological follow-up study was carried out on 27 children (1–12 years old) with visceral and/or ocular toxocariasis, after treatment with thiabendazole. A total of 159 serum samples were collected in a period ranging from 22–116 months. Enzyme-linked immunosorbent assays (IgG, IgA, and IgE ELISA) were standardized, using excretory–secretory antigens obtained from the second-stage larvae of a Toxocara canis culture. The sensitivity found for the IgG, IgA, and IgE ELISA, as determined in visceral toxocariasis patients, was 100%, 47.8%, and 78.3%, respectively. Approximately 84% of the patients presented single or multiple parasitosis, as diagnosed by stool examination, yet such variables did not appear to affect the anti-Toxocara immune response. Titers of specific IgE antibody showed a significant decrease during the first year after treatment, followed by a decrease in the IgA titers in the second year, and in the IgG titers from the fourth year onwards. Sera from all patients presented high avidity IgG antibodies, indicating that they were in the chronic phase of the disease. Moreover, 1 year after treatment, the level of leukocytes, eosinophils, and anti-A isohemagglutinin in patients decreased significantly. The present data suggest that IgE antibodies plus eosinophil counts are helpful parameters for patient followup after chemotherapy.

Aquaporin-4 Antibodies Are Not Related to HTLV-1 Associated Myelopathy

Introduction: The seroprevalence of human T-cell leukemia virus type 1 (HTLV-1) is very high among Brazilians (,1:200). HTLV-1 associated myelopathy or tropical spastic paraparesis (HAM/TSP) is the most common neurological complication of HTLV-1 infection. HAM/TSP can present with an acute/subacute form of longitudinally extensive myelitis, which can be confused with lesions seen in aquaporin-4 antibody (AQP4-Ab) positive neuromyelitis optica spectrum disorders (NMOSD) on MRI. Moreover, clinical attacks in patients with NMOSD have been shown to be preceded by viral infections in around 30% of cases. Objective: To evaluate the frequency of AQP4-Ab in patients with HAM/TSP. To evaluate the frequency of HTLV-1 infection in patients with NMOSD. Patients and Methods: 23 Brazilian patients with HAM/TSP, 20 asymptomatic HTLV-1+ serostatus patients, and 34 with NMOSD were tested for AQP4-Ab using a standardized recombinant cell based assay. In addition, all patients were tested for HTLV-1 by ELISA and Western blotting. Results: 20/34 NMOSD patients were positive for AQP4-Ab but none of the HAM/TSP patients and none of the asymptomatic HTLV-1 infected individuals. Conversely, all AQP4-Ab-positive NMOSD patients were negative for HTLV-1 antibodies. One patient with HAM/TSP developed optic neuritis in addition to subacute LETM; this patient was AQP4-Ab negative as well. Patients were found to be predominantly female and of African descent both in the NMOSD and in the HAM/TSP group; Osame scale and expanded disability status scale scores did not differ significantly between the two groups. Conclusions: Our results argue both against a role of antibodies to AQP4 in the pathogenesis of HAM/TSP and against an association between HTLV-1 infection and the development of AQP4-Ab. Moreover, the absence of HTLV-1 in all patients with NMOSD suggests that HTLV-1 is not a common trigger of acute attacks in patients with AQP4-Ab positive NMOSD in populations with high HTLV-1 seroprevalence.

Anti-Toxocara spp. antibodies in an adult healthy population: serosurvey and risk factors in Southeast Brazil.

Objective: To evaluate the frequency of anti-Toxocara spp. antibodies in an adult healthy population. Methods: The study was performed by interviewing 253 blood donors, from 19 to 65 years of age, in a hematological centre in Presidente Prudente, São Paulo, southeast Brazil. A survey was applied to blood donors in order to evaluate the possible factors associated to the presence of antibodies, including individual (gender and age), socioeconomic (scholarship, familial income and sanitary facilities) and habit information (contact with soil, geophagy, onycophagy and intake of raw/undercooked meat) as well as the presence of dogs or cats in the household. ELISA test was run for detection of the anti-Toxocara spp. IgG antibodies. Bivariate analysis followed by logistic regression was performed to evaluate the potential risk factors associated to seropositivity. Results: The overall prevalence observed in this study was 8.7% (22/253). Contact with soil was the unique risk factor associated with the presence of antibodies (P=0.0178 ; OR=3.52; 95% CI=1.244-9.995) Conclusions. The results of this study reinforce the necessity in promoting preventive public health measures, even for healthy adult individual, particularly those related to the deworming of pets to avoid the soil contamination, and hygiene education of the population.

Experimental antiviral therapy against different rabies virus lineages using transfection with anti-rabies antibodies

Financial Support: FAPESP

Antismooth Muscle and Antiactin Antibodies Are Indirect Markers of Histological and Biochemical Activity of Autoimmune Hepatitis

Reactivity and titers of autoantibodies vary during the course of autoimmune hepatitis (AIH), and some autoantibodies have been associated with disease activity and adverse outcomes after treatment. The aim of this study was to assess the autoantibody behavior in AIH and its significance as predictors of biochemical and histological remission. A total of 117 patients with AIH (mean age 18.6 [4-69] years) were evaluated and tested for auto- antibodies at disease onset and successively (mean 3.2 [2-6] times) after a mean follow-up evaluation of 70 [20-185] months. Antismooth muscle (ASMA), antiliver kidney micro- some type 1 (anti-LKM1), antiliver cytosol type 1 (anti-LC1), antimitochondrial, antinu- clear (ANA), and antiactin antibodies (AAA) were determined at disease onset and 379 other times during the follow-up evaluation through indirect immunofluorescence in rodent tissues, HEp-2 cells, and human fibroblasts. Anti-SLA/LP were assessed 45 times in the follow-up evaluation of 19 patients using enzyme-linked immunosorbent assay (ELISA). Upon admission, AIH types 1 and 2 were observed in 95 and 17 patients, respectively. Five subjects had AIH with anti-SLA/LP as the sole markers. Patients initially negative for AAA did not develop these antibodies thereafter. ANA were detected de novo in six and three subjects with AIH types 1 and 2, respectively. After treatment, only ASMA ( > 1:80) and AAA ( > 1:40) were significantly associated with biochemical (76.9% and 79.8%) and histological features (100% and 100%) of disease activity ( P < 0.001). Conclusion: With the exception of ANA, the autoantibody profile does not markedly vary in the course of AIH. The persistence of high titers of ASMA and/or AAA in patients with AIH is associated with disease activity.

Cruising for ocean conservation: no exactly a waste of time. Plastic pollution in the oceans

Grabación realizada por Ciencia compartida (Biblioteca Universitaria)

Use of E. coli OMVs as delivery system to elicit neutralizing antibodies against Chlamydia infectivity: the HtrA protein example

The obligate intracellular pathogen Chlamydia trachomatis is a gram negative bacterium which infects epithelial cells of the reproductive tract. C. trachomatis is the leading cause of bacterial sexually transmitted disease worldwide and a vaccine against this pathogen is highly needed. Many evidences suggest that both antigen specific-Th1 cells and antibodies may be important to provide protection against Chlamydia infection. In a previous study we have identified eight new Chlamydia antigens inducing CD4-Th1 and/or antibody responses that, when combined properly, can protect mice from Chlamydia infection. However, all selected recombinant antigens, upon immunization in mice, elicited antibodies not able to neutralize Chlamydia infectivity in vitro. With the aim to improve the quality of the immune response by inducing effective neutralizing antibodies, we used a novel delivery system based on the unique capacity of E. coli Outer Membrane Vesicles (OMV) to present membrane proteins in their natural composition and conformation. We have expressed Chlamydia antigens, previously identified as vaccine candidates, in the OMV system. Among all OMV preparations, the one expressing HtrA Chlamydia antigen (OMV-HtrA), showed to be the best in terms of yield and quantity of expressed protein, was used to produce mice immune sera to be tested in neutralization assay in vitro. We observed that OMV-HtrA elicited specific antibodies able to neutralize efficiently Chlamydia infection in vitro, indicating that the presentation of the antigens in their natural conformation is crucial to induce an effective immune response. This is one of the first examples in which antibodies directed against a new Chlamydia antigen, other than MOMP (the only so far known antigen inducing neutralizing antibodies), are able to block the Chlamydia infectivity in vitro. Finally, by performing an epitope mapping study, we investigated the specificity of the antibody response induced by the recombinant HtrA and by OMV-HtrA. In particular, we identified some linear epitopes exclusively recognized by antibodies raised with the OMV-HtrA system, detecting in this manner the antigen regions likely responsible of the neutralizing effect.