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Neutralizing antibodies (nAbs) are a critical part of coronavirus disease 2019 (COVID-19) research as they are used to gain insight into the immune response to severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) infections. Among the technologies available for generating nAbs, DNA-based immunization methods are an alternative to conventional protocols. In this pilot study, we investigated whether DNA-based immunization by needle injection in rabbits was a viable approach to produce a functional antibody response. We demonstrated that three doses of DNA plasmid carrying the gene encoding the full-length spike protein (S) or the receptor binding domain (RBD) of SARS-CoV-2 induced a time-dependent increase in IgG antibody avidity maturation. Moreover, the IgG antibodies displayed high cross neutralization by live SARS-CoV-2 and pseudoviruses neutralization assays. Thus, we established a simple, low cost and feasible DNA-based immunization protocol in rabbits that elicited high IgG avidity maturation and nAbs production against SARS-CoV-2, highlighting the importance of DNA-based platforms for developing new immunization strategies against SARS-CoV-2 and future emerging epidemics.

Objective:  To evaluate the performance of the hybrid capture 2 (HC2) high-risk papillomavirus (hrHPV) assay and cytological test in women with previous abnormalities, to detect cervical intraepithelial neoplasia grade 2 or worse (≥ CIN 2)., Methods:  A cytological test and HC2 (Qiagen, Gaithersburg, Maryland, EUA) for hrHPV were conducted in 359 liquid-based (Sure Path, Becton Dickinson, TriPath Imaging, Burlington, NC, USA) samples collected from women from the Vale do Ribeira Region, during July 2013 and September 2015 with previous cytology classified as atypical squamous cells of undetermined significance (ASC-US), low-grade squamous intraepithelial lesion (LSIL), atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesions (ASC-H), and atypical glandular cells (AGC). The histopathological examination was conducted in 179 women. The performance evaluations were calculated using the "exact" Clopper-Pearson 95% confidence interval (CI) test by MEDCALC (Medcalc Software Ltd, Ostend, Belgium)., Results:  The ≥ CIN 2 frequency was 11.7% (21/179). The HC2 for hrHPV and repeat cytology to detect ≥ CIN 2 obtained, respectively, a sensitivity of 90.5% (95%CI = 69.6-98.8) and 90.5%, (95%CI = 69.6-98.8), a specificity of 65.8% (95% CI = 57.9-73.2) and 43.7% (95%CI = 35.8-51.8), a positive predictive value of 26.0% (95% CI = 21.4-31.3) and 17.6%, (95%CI = 14.9-20.6), and a negative predictive value of 98.1% (95%CI = 93.3-99.5) and 97.2% (95% CI = 90.1-99.2)., Conclusion:  Hybrid capture 2 for hrHPV improves the performance of the detection of ≥ CIN 2, without compromising sensitivity, and provides a greater safety margin to return to the triennial screening of women undergoing follow-up due to previous abnormalities, without underlying ≥ CIN 2., Competing Interests: Dr. Lorente has nothing to disclose., (Thieme Revinter Publicações Ltda Rio de Janeiro, Brazil.)

Objectives: Iodine deficiency during pregnancy is associated with obstetric and neonatal adverse outcomes. Serum thyroglobulin (sTg) and thyroid volume (TV) are optional tools to urinary iodine concentration (UIC) for defining iodine status. This cross-sectional study aims to evaluate the iodine status of pregnant women living in iodine-adequate area by spot UIC and correlation with sTg, TV and thyroid function., Methods: Two hundred and seventy-three pregnant women were evaluated at three trimesters. All had no previous thyroid disease, no iodine supplementation and negative thyroperoxidase and thyroglobulin antibodies. Thyroid function and sTg were measured using electrochemiluminescence immunoassays. TV was determined by ultrasonography; UIC was determined using a modified Sandell-Kolthoff method., Results: Median UIC was 146 µg/L, being 52% iodine deficient and only 4% excessive. TSH values were 1.50 ± 0.92, 1.50 ± 0.92 and 1.91 ± 0.96 mIU/L, respectively, in each trimester ( P  = 0.001). sTg did not change significantly during trimesters with median 11.2 ng/mL and only 3.3% had above 40 ng/mL. Mean TV was 9.3 ± 3.4 mL, which positively correlated with body mass index, but not with sTg. Only 4.5% presented with goitre.When pregnant women were categorized as iodine deficient (UIC < 150 µg/L), adequate (≥150 and <250 µg/L) and excessive (≥250 µg/L), sTg, thyroid hormones and TV at each trimester showed no statistical differences., Conclusions: Iodine deficiency was detected frequently in pregnant women living in iodine-adequate area. sTg concentration and TV did not correlate to UIC. Our observation also demonstrated that the Brazilian salt-iodization programme prevents deficiency, but does not maintain iodine status within adequate and recommended ranges for pregnant women., (© 2018 The authors.)

Purpose: To analyze the impact of selenium supplementation on serum antiTPO levels and thyroid echogenicity in patients with CAT, evaluating the response in subgroups with different GPx1 genotypes., Methods: CAT patients (n = 55) with positive antiTPO were randomized to selenomethionine (SeMet) 200 μg daily (n = 28) or placebo (n = 27) for 3 months. Assessments included GPx1 genotyping at baseline and serum levels of plasma selenium, erythrocyte GPx1 activity, antiTPO and thyroid echogenicity at baseline, and 3 and 6 months., Results: In the SeMet group, the increase in plasma levels of selenium and erythrocyte GPx1 activity was similar among patients with different GPx1 genotypes. In the overall cohort, patients randomized to SeMet showed a 5 % decrease in antiTPO levels at 3 months (p = non-significant) and 20 % at 6 months (p < 0.001 versus 3 months). In contrast, patients in the placebo group did not show significant changes in antiTPO levels at any time point. Subgroup analysis showed that patients with different GPx1 genotypes presented comparable responses in antiTPO levels and echogenicity index to SeMet., Conclusions: Selenium supplementation decreased serum antiTPO levels in CAT patients, with similar response among patients with different GPx1 genotypes.

Purpose: To validate the use of the ratio between the total transverse diameters of the thyroid lobes (Th) and the width of the trachea (Tr)-the Th:Tr or Yasumoto ratio-as a sonographic method for estimating thyroid size, and to determine reference values for this ratio and for thyroid volume in neonates., Methods: In this cross-sectional study, we evaluated thyroid size according to the Yasumoto ratio and the thyroid volume calculated with the ellipsoid formula in 125 healthy, euthyroid, iodine-sufficient, full-term neonates., Results: The mean thyroid gland volume was 1.00 ml (95% confidence interval, 0.95-1.03 ml), and the mean Yasumoto ratio was 2.29 (95% confidence interval, 2.21-2.31). The lower- and upper-limit results falling within 2 SDs of the mean were 0.45 ml and 1.53 ml for the volume and 1.71 and 2.87 for the ratio., Conclusions: In full-term, euthyroid, iodine-sufficient neonates, the normal reference interval for thyroid volume measured on sonography was 0.45-1.53 ml and that for the Yasumoto ratio was 1.71-2.87. A ratio of 1.7 may be applied as the cutoff value for sonographic diagnosis of thyroid dysgenesis in full-term neonates with congenital hypothyroidism. © 2014 Wiley Periodicals, Inc. J Clin Ultrasound 43:224-229, 2015., (© 2014 Wiley Periodicals, Inc.)

Background: Since several countries have established mandatory food iodine fortification, there has been a decrease in rates of iodine deficiency disorders in parallel with an increase in prevalence of autoimmune thyroid diseases. This study compared the nutritional iodine status and the prevalence of autoimmune thyroiditis and thyroid hypoechogenicity on ultrasound in schoolchildren in São Paulo (Brazil) in two distinct periods of time in which fortified salt had different concentrations of iodine., Methods: We conducted a cross-sectional study evaluating 206 children aged 7-14 years and without a history of thyroid disease. Assessments included measurements of thyrotropin (TSH), free thyroxine, antithyroperoxidase (anti-TPO), and antithyroglobulin (anti-TG) antibodies, urinary iodine concentration, and thyroid ultrasound., Results: Mean urinary iodine concentration was 165.1 μg/L. Eleven children (5.3%) were diagnosed with autoimmune thyroiditis based on at least two of four criteria adopted in our study: positive anti-TPO or anti-TG antibody, hypoechogenicity of the thyroid parenchyma on ultrasound, and a TSH >4.0 μU/mL. Comparing our results with those from a similar study conducted during a period in which concentrations of iodine in the salt were higher (median urinary iodine concentration >300 μg/L), we observed a trend toward a lower prevalence of autoimmune thyroiditis, although no definitive conclusion could be established., Conclusion: The current nutritional iodine status in our cohort was within optimal levels and lower than levels found in 2003. The prevalence of autoimmune thyroiditis seems to be decreasing in parallel with a decrease in iodine intake, although we could not reach a definitive conclusion.

Background: Modifications of oxidative stress are reported in hepatitis C. The relationship between insulin resistance (IR), steatosis and oxidative stress is not established., Materials and Methods: One hundred and eighty-seven HCV-RNA patients were assessed by determination of biochemical, metabolic and viral features, HOMA-IR and morphological alterations. In the 52-non-3 genotypes sub-group and 35 healthy individuals, thiobarbituric acid (TBARS), total glutathione (total-GSH), vitamins C and E, lycopene, beta-carotene, glutathione peroxidase (GPx), catalase and superoxide dismutase were determined., Results: In non-3 genotype patients, steatosis was associated with higher values of BMI, HOMA-IR and triglycerides. In the 52-HCV sub-group, values of TBARS, GPx and total-GSH differ from the control group. Despite these, differences could not be observed according to the presence of steatosis, patients with IR presented significant differences regarding total-GSH (p=0.019), beta-carotene (p=0.006), lycopene (p=0.005) and GPx (p=0.009)., Conclusion: In non-3 genotype HCV carries, IR, and not steatosis, is associated with modifications in serum levels of oxidative stress.

High nutritional levels of iodine may induce a higher prevalence of autoimmune thyroiditis, hypothyroidism, goiter, as well as hyperthyroidism, mostly in the elderly. This study assessed thyroid volume and ultrasonographic abnormalities as well as urinary iodine excretion (UIE) in 964 schoolchildren living in an iodine-sufficient area in southern Brazil. Thyroid volume correlated with age and body surface area in boys and girls. In 76.8% of the children, UIE was above 300 microg/l, with higher levels among boys compared to girls (484.2 microg/l vs 435.3 microg/l, p < 0.001). Thyroid abnormalities detected by ultrasonography included hemiagenesis (0.5%), nodules (0.2%), cysts (0.7%), and hypoechogenicity (11.7%). Goiter was present in 1.9% of the children. Hypoechogenicity, a relevant marker of autoimmune thyroiditis, was the most common abnormality found in our study, and this may be linked to excessive iodine intake.

Laminin levels in ascitic fluid have been proposed as a marker for neoplastic ascites. We compared the concentration of laminin in serum and in ascitic fluid from patients with hepatic cirrhosis and peritoneal carcinomatosis and assessed the diagnostic value of serum laminin levels in differentiating neoplastic from benign ascites. Laminin concentrations were determined by ELISA with antibodies against laminin extracted from the human placenta, in patients with ascites due to peritoneal carcinomatosis (N = 20) and hepatic cirrhosis (N = 33). Patients with infected or hemorrhagic ascites were excluded. The receiver operating characteristic curve was used to determine the sensitivity and specificity of serum laminin for the diagnosis of neoplastic ascites. When compared to the group with cirrhosis, the carcinomatosis group presented significantly higher mean laminin levels in serum (3.3 +/- 0.5 vs 2.1 +/- 0.4 microg/ml, mean +/- SD, P < 0.05) and ascites (2.8 +/- 0.5 vs 1.6 +/- 0.4 microg/ml, P < 0.05). Although laminin concentration was higher in serum than in ascites, the laminin serum/ascites ratio and serum-ascites gradient did not differ between the studied groups. A significant correlation (r = 0.93, P < 0.0001) was observed between the serum and ascites laminin values. Serum laminin levels >2.25 microg/ml showed 100% sensitivity and 73% specificity for the diagnosis of neoplastic ascites. Serum concentration seems to be the main determinant of laminin levels in ascitic fluid and its values can be used as a diagnostic parameter in the study of neoplastic ascites.

We have examined, by ultrasonographic studies, the thyroid gland of 844 schoolchildren, aged between 6 and 14 years old (423 girls, 421 boys). There was a progressive increase of the thyroid volume with aging with a positive and significant correlation with the body surface area. The presence of enlarged thyroid gland was rarely seen, being present in only 1.6% of the studied cohort. A few thyroid gland abnormalities were noticed such as hemiagenesia (4 children), nodules and cysts and hypoechogenicity (total: 1.4% of all subjects examined). It was clearly demonstrated that the urinary excretion of iodine was elevated being above 300 microg Iodine/L in 53% of the schoolchildren examined. Assays for the iodine concentration in the domestic salt samples revealed values between 28.1 and 63.3 mgI/kg of salt. We concluded that the schoolchildren population of the State of São Paulo may be under an excessive daily ingestion of iodine. This may induce, if extrapolated to the general population, subclinical hyperthyroidism in the elderly and possibly an increment in the prevalence of chronic autoimmune thyroiditis.

Background: Serum laminin has been correlated with portal hypertension and sinusoid capillarization in chronic liver diseases. Little is known about its dynamics in liver diseases., Aim: To investigate the levels of serum laminin in experimental cirrhosis induced by carbon tetrachloride, as well as to correlate its level with the degree of hepatic fibrosis and portal hypertension., Material and Methods: Forty-nine albino Wistar rats were studied. Twenty-three were treated with carbon tetrachloride solution at 8% and 16 were kept as controls. Between the 6th and 16th weeks, all animals were sacrificed, submitted to measurement of portal pressure and blood sampling of the femoral veins. Liver fragments were fixed for light microscopic studies. Hepatic fibrosis was classified as perivenular fibrosis, complete and incomplete septal fibrosis and cirrhosis. Determination of laminin concentration was performed by ELISA with an antibody against laminin isolated from Engelbreth-Holm-Swarm tumor., Results: The portal pressure was correlated with the degree of hepatic fibrosis (rs = 0.82; n = 45). Its levels in septal fibrosis (10.8 +/- 1.2 cm H(2)0) and cirrhosis (13.6 +/- 3.1 cm H(2)0) were statistically higher when compared to control (7.9 +/- 1.5 cm H20) and perivenular fibrosis (9.1 +/- 0.8 cm H(2)0) groups. Peripheral blood laminin concentration in cirrhosis (40.0 +/- 18.7 mg/dL) was significantly higher when compared to control (13.8 +/- 12.1 mg/dL), perivenular fibrosis (19.1 +/- 15.5 mg/dL) and septal fibrosis (22.2 +/- 27.0 mg/dL) groups. The circulating laminin was correlated to the degree of hepatic fibrosis (rs = 0.59; n = 49) and to portal pressure (r = 0.29; n = 45)., Conclusions: In the chronic carbon tetrachloride intoxication, laminin levels are better correlated with the development of hepatic fibrosis than with portal hypertension.

Background/aims: Estrogen (ER) and progesterone receptors (PR) have been evaluated in gastrointestinal cancer by several groups with conflicting results. The aim of the study is to examine the presence of these receptors in gastric and colon cancer., Methodology: Estrogen (ER) and progesterone (PR) receptors were assayed by the dextran-coated charcoal adsorption method from malignant and normal adjacent tissues in 16 patients with gastric adenocarcinomas and in 10 with colorectal adenocarcinomas., Results: In gastric cancer, ER were detected in 62.5% and PR in 75% of the patients. In colorectal cancer, the ER and PR were detected in 60% of the patients. The binding activity ranged from 1.14-9.27 fmol/mg protein for estradiol and from 1.43-10.84 fmol/mg protein for progesterone. ER and PR were detected in normal gastric tissue in 62.5% and in 50%, respectively. In the normal colorectal tissue the ER and PR were detected in 30% and 50%. ER ranged from 1.20-16.63 fmol/mg protein for estradiol and from 1.44-9.94 fmol/mg protein for progesterone. There was no statistical difference in levels of ER and PR in both tissues., Conclusions: ER and PR were detected in normal and cancer tissues in low levels, suggesting a feature of the tissue rather than a consequence of a malignant process. Eventual role of ER or PR in these cancers remains to be elucidated.