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Background: In the atherosclerotic plaque microenvironment, oxidized phospholipids expressed in the oxidized low-density lipoprotein (oxLDL) surface bind to scavenger receptors of macrophages eliciting foam cell formation and plaque progression. Auto-antibodies against oxLDL (oxLDL-Ab) interact with oxidative epitopes leading to the formation of immune complexes that are unable to interact with macrophage receptors, thus abrogating atherogenesis. Release of oxLDL-Ab by B cells involves interleukin 5 and Th2 response, which in turn are potentiated by HDL. Thereby, we hypothesized that individuals with higher levels of HDL-C may plausibly display elevated titers of oxLDL-Ab., Objective: To evaluate the relationship between HDL-C and oxLDL-Ab levels., Methods: Asymptomatic individuals (n = 193) were grouped according to their HDL-C concentration to one of three categories: low (< 68 mg/dL), intermediate (68 to 80 mg/dL) or high (> 80 mg/dL). P values < 0.05 were considered statistically significant., Results: Our analysis included 193 individuals (mean age: 47 years; male: 26.3%). Compared to individuals in the lowest HDL-C tertile, those in the highest tertile were older (36 versus 53 years; p = 0.001) and less frequently male (42.6% versus 20.9%; p = 0.001). Mean values of oxLDL-Ab increased as the HDL-C group escalated (0.31, 0.33 and 0.43 units, respectively; p = 0.001 for trend). Simple linear regression found a significant, positive relationship between the independent variable, HDL-C, and the dependent variable, oxLDL-Ab (R = 0.293; p = 0.009). This relation remained significant (R = 0.30; p = 0.044), after adjustment by covariates. Apolipoprotein AI levels were also related to oxLDL-Ab in both simple and adjusted linear regression models., Conclusion: HDL-C and oxLDL-Ab are independently related.

A SARS-CoV-2 B.1.1.7 variant of concern (VOC) has been associated with increased transmissibility, hospitalization, and mortality. This study aimed to explore the factors associated with B.1.1.7 VOC infection in the context of vaccination. On March 2021, we detected SARS-CoV-2 RNA in nasopharyngeal samples from 14 of 22 individuals vaccinated with a single-dose of ChAdOx1 (outbreak A, n = 26), and 22 of 42 of individuals with two doses of the CoronaVac vaccine (outbreak B, n = 52) for breakthrough infection rates for ChAdOx1 of 63.6% and 52.4% for CoronaVac. The outbreaks were caused by two independent clusters of the B.1.1.7 VOC. The serum of PCR-positive symptomatic SARS-CoV-2-infected individuals had ~1.8-3.4-fold more neutralizing capacity against B.1.1.7 compared to the serum of asymptomatic individuals. These data based on exploratory analysis suggest that the B.1.1.7 variant can infect individuals partially immunized with a single dose of an adenovirus-vectored vaccine or fully immunized with two doses of an inactivated vaccine, although the vaccines were able to reduce the risk of severe disease and death caused by this VOC, even in the elderly.

Globally, vitamin A deficiency (VAD) affects about 19.1 million pregnant women. Its occurrence is classically associated with inadequate food intake and may also be associated with socioeconomic factors and the presence of infection. The aim of this study was to determine the factors related to serum retinol levels among pregnant teenagers. The sample consisted of 89 pregnant adolescents, from whom socioeconomic, obstetric, anthropometric, and food consumption data were collected. Serum concentrations of retinol and the supposed presence of infection were determined by high-performance liquid chromatography and C-reactive protein quantification, respectively. The serum retinol concentrations were classified according to the criteria of the World Health Organization. We adopted a 5% significance level for all statistical tests. Serum retinol levels were significantly and positively associated with sanitation ( p = 0.008) and pre-gestational nutritional status ( p = 0.002), and negatively with the trimester ( p = 0.001). The appropriate sanitation conditions and pre-pregnancy body mass index (BMI) were shown to have a protective effect against VAD. Conversely, serum retinol levels were reduced with trimester progression, favoring VAD occurrence., Competing Interests: The authors declare no conflict of interest.

Serum amyloid A (SAA) is an acute-phase protein and also an adipokine, which has been associated with the development and prognosis of breast cancer. In the present study, we investigated the association between obesity and SAA in postmenopausal women with breast cancer and its relationship with clinicopathologic characteristics of tumors. Patients were grouped as nonobese or overweight/obese based on body mass index (BMI) plus waist circumference measurement. Serum SAA concentrations were determined by high-sensitivity micro-latex agglutination tests, detected by nephelometry. Serum SAA concentrations were higher in overweight/obese (P = 0.008) patients and this condition was dependent on obesity (BMI and waist circumference), as further shown by multivariate linear regression analysis done for SAA (P = 0.01). Concentrations of SAA were also higher in patients with estrogen receptor-negative (ER(-)) tumors than in those with estrogen receptor-positive (ER(+); P = 0.033). Our results suggest a possible role for SAA in the development and prognosis of obesity-related breast cancer. A follow-up study of this population to assess overall and disease-free survival is in course and should bring contribution to evaluate the clinical role of SAA in breast cancer in the context of obesity.

We report a primary response to Toxoplasma gondii following a hematopoietic stem cell transplantation in a patient with multiple myeloma. The primary response to T. gondii was supported by IgM, IgG and IgA seroconversion. The patient was promptly treated and there were no complications related to toxoplasmosis in the subsequent months.

Background: Cerebrospinal fluid (CSF) leak of the anterior skull base is an abnormal communication between the subarachnoid space and the nasal cavity or the paranasal sinus. Its presence increases the incidence of complications, as meningitis, with risk of sequelae. The early and correct diagnosis of the CSF leaks is important to perform surgical treatment as soon as possible. The CSF detection in nasal fluids could be made through the beta2-transferrin (beta2Tr) immunoelectrophoretic test, an expensive and cumbersome immunologic test, not available to the majority of the Brazilian hospitals. Recently, the detection of beta-trace protein (betaTP) for identification of CSF leaks has been described. The literature suggests there may be similar sensitivity and specificity to tests of beta2Tr, because betaTP is also a specific brain protein and it is present in CSF in high concentrations. The majority of Brazilian hospitals have the nephelometric equipment for betaTP detection. This study was designed to determine threshold values for betaTP concentrations in nasal cavity secretions as a predictor of CFS leak., Methods: Nasal secretions were collected from patients with suspicion of CSF leak and from healthy volunteers. Pure CSF samples were used. A nephelometric assay was used to determine the betaTP concentration in samples., Results: Values between 0.244 and 0.496 mg/L were determined for the cutoff., Conclusion: Beta-trace concentrations above 0.496 mg/L are highly suggestive of the presence of CSF in examined nasal secretion. Positive predictive value and negative predictive value were 100%. BetaTP nephelometric test can predict the side of the CSF leak.

Background: It has been proposed that there is improvement in glucose and insulin metabolism after weight loss in patients who underwent diet restriction and bariatric surgery., Methods: Eleven normal glucose tolerant (NGT) morbidly obese patients [body mass index (BMI), 46.1+/-2.27 g/m2] and eight abnormal glucose metabolism (AGM) obese patients (BMI, 51.20 kg/m2) were submitted to diet-restriction and bariatric surgery. Prospective study on weight loss changes, over the glucose, insulin metabolism, glucagon-like peptide-1 (GLP-1), and adiponectin levels were evaluated by oral glucose tolerance test during three periods: T1 (first evaluation), T2 (pre-surgery), and T3 (9 months after surgery)., Results: Insulin levels improved after surgery. T1 was 131.1+/-17.60 pmol/l in the NGT group and 197.57+/-57.94 pmol/l in the AGM group, and T3 was 72.48+/-3.67 pmol/l in the NGT group and 61.2+/-9.33 pmol/l in the AGM group. The major reduction was at the first hour of the glucose load as well as fasting levels. At 9 months after surgery (T3), GLP-1 levels at 30 and 60 min had significantly increased in both groups. It was observed that the AGM group had higher levels of GLP-1 at 30 min (34.06+/-6.18 pmol/l) when compared to the NGT group (22.69+/-4.04 pmol/l). Homeostasis model assessment of insulin resistance from the NGT and AGM groups had a significant reduction at periods T3 in relation to T1 and T2. Adiponectin levels had increased concentration in both groups before and after surgical weight loss. However, it did not have any statistical difference between periods T1 vs. T2., Conclusions: Weight loss by surgery leads to improvement in the metabolism of carbohydrates in relation to sensitivity to the insulin, contributing to the reduction of type 2 diabetes incidence. This improvement also was expressed by the improvement of the levels of adiponectin and GLP-1.

Objectives: Human papillomavirus (HPV) infection is one of the most common sexually transmitted diseases worldwide. We determined the frequency of HPV in the oral cavity of women with and without genital HPV lesions., Material and Methods: All patients were seen at the Department of Gynecology, Women's Health Center and the State University of Campinas, Sao Paulo, Brazil and submitted to a general physical and gynecological examination plus an evaluation of the oral cavity. Detailed histories investigated their sexual practices. HPV in the oral cavity was determined by polymerase chain reaction using consensus primers in 70 women presenting with histopathology-confirmed clinical HPV lesions in the genital region and 70 women negative by gynecological, colposcopic and cytological examination for clinical or subclinical HPV lesions., Results: Oral HPV was detected in 29 (20.7%) of the subjects. Among the positive women, 26 (89.7%) were also positive for genital HPV as opposed to only 3 (2.7%) who were genital HPV-negative (p < 0.0001). The overall prevalence of HPV in the oral cavity of patients with and without genital HPV was 37.1 and 4.3%, respectively, (p < 0.0001). The presence of oral HPV was unrelated to the practice of fellatio (22% versus 19%)., Conclusion: Patients with HPV genital infection have a greater frequency of HPV in their oral mucosa.

Unlabelled: Secretory IgA contributes towards the protection of mucosal surfaces against invading microorganisms., Objectives: Quantify secretory IgA titers in the saliva of women with HPV in the oropharynx and/or in the genital area., Subjects and Methods: Seventy women with clinical genital HPV lesions and 70 women without HPV infection were tested for oral HPV DNA and the levels of total IgA in their saliva. One millilitre of saliva was collected, centrifuged and stored at -80 degrees C for the measurement of secretory IgA by nephelometry technique. A pool of oral pharyngeal cells was collected for HPV identification by polymerase chain reaction., Results: Oral HPV PCR was positive in 29 (21%) women (26 women with genital HPV and only 3 women without genital HPV). Titers of secretory IgA were extremely lower in-patients with HPV DNA in the oropharynx when compared to HPV negative women (p<0.0001). Genital HPV and smoking were also associated to low levels of total sIgA in saliva (p<0.01). After multivariable analyses only the presence of HPV in the oral cavity and/or in genital area, but not smoking, was related to low levels of total secretory IgA., Conclusion: Women with low levels of total secretory IgA could be more susceptible to having their oral mucosa colonized by HPV.

In the search to identify differences in the immunological response between patients with the indeterminate or cardiac form of Chagas disease, trypomastigote-specific peripheral blood mononuclear cell (PBMC) proliferative responses were studied. Suppression of lymphoproliferation occurred in both groups of patients, being more intense in those with the cardiac form. By adding to the cultures neutralizing mAbs anti-IFN-gamma, anti-IL-4, anti-IL-13, or anti-IL-10, indomethacin to block prostaglandin synthesis, NMMA as inhibitor of nitric oxide (NO) synthesis, or glutathione-peroxidase as H(2)O(2) scavenger, it was found that indomethacin augmented lymphoproliferation in both groups of patients. However, anti-IL-10 treatment increased proliferation only in PBMC cultures from patients with the cardiac form, indicating that in these patients, IL-10 was suppressing the immune response. These patients also had higher IL-10 levels in unstimulated cultures and higher PGE(2) levels in stimulated cultures. The results evidence that IL-10 regulates parasite-specific T cell responses in patients with the cardiac form, whereas regulation by prostaglandins (PG) occurs in patients with either cardiac or indeterminate form of the disease.

Chagas' disease is caused by infection with Trypanosoma cruzi. Patients in the chronic phase of infection were grouped as belonging to the asymptomatic (or indeterminate), cardiac and cardiac plus digestive forms. Previous studies have described abnormal immune responsiveness by peripheral blood mononuclear cells (PBMC) from chronic chagasic patients. We report significant parasite antigen (T-Ag)-stimulated PBMC proliferative responses to be present in all three groups of patients. Treatment of T-Ag-stimulated cultures with rIL-12 significantly amplifies proliferative responses in all patients' groups, with similar rates of increment. IL-12 enhances T-Ag-specific lymphoproliferation without increasing proliferation of unstimulated PBMC from normal individuals or from patients. Comparatively, treatment with rIL-2 enhances both T-Ag-specific and unstimulated proliferation by PBMC from patients and normals. Thus, IL-12 acts on pre-activated cells while IL-2 also stimulates resting cells. No synergism was obtained by the combined use of IL-12 and IL-2. Therefore IL-12 can act as a more selective amplifier of T. cruzi reactive cells than IL-2. IL-12, by enhancing parasite-antigen specific immunity, could be of potential therapeutic use to control reactivated T. cruzi infections concomitant to AIDS or other situations of immunosuppression.

Aqueous-soluble (AS) antigens from larvae of Strongyloides stercoralis, extracted with phosphate-buffered saline, are traditionally used for serodiagnosis of strongyloidiasis. To identify sources of antigens for use in serodiagnosis, residual particulates from parasite larvae after aqueous extraction were solubilized with Tris-buffered 8M urea, yielding a urea-soluble (US) antigen fraction. Both AS and US antigens from S. stercoralis were evaluated by an enzyme-linked immunosorbent assay. No significative differences were observed between AS and US antigens from the parasite regarding specific antigenic activity and cross-reactivity. Immunoassays are highly dependent on the antigen for sensitivity and specificity. Crude extracts from S. stercoralis should be further studied, mainly in relation to antigenic fractions which could provide even more sensitive and specific results. Studies of fractionation of S. stercoralis must take into account the antigen yield of both the crude extract and fractions, since larvae of parasite are normally difficult to obtain. Considering this aspect, the results from this study are very useful, since the extraction with urea substantially increased the amounts of antigenic materials normally obtained with the classical aqueous extraction.

A retrospective study of laboratory records in a 400-bed university hospital in Campinas city, SP (Southeastern Brazil) suggests that infection by Strongyloides stercoralis is widespread in the region. A prevalence of 10.81% was found in 37,621 stool specimens examined in a two-year period. Parasite-specific IgG antibodies were measured by ELISA in sera from 90 patients with strongyloidiasis. The ELISA detected antibody in 76 (84.44%) patients, indicating that serodiagnostic tests may be helpful in screening patients for strongyloidiasis.