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OBJECTIVE: This study aimed to investigate the seropositivity of CoronaVac-SinoVac vaccination in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) risk factors and comorbidities. METHODS: Immunoglobulin (IgG) antibody responses were examined on the 21st day after the second dose of CoronaVac-SinoVac 6 ?g vaccine on the 28th day. SARS-CoV-2 IgG antibody levels were measured by using the enzyme-linked immunosorbent assay method in vaccinated health care workers (n=134) (Group I), vaccinated polymerase chain reaction (PCR) (+) who had coronavirus-19 (COVID-19) disease (n=21) (Group II), and unvaccinated PCR (+) (n=28) (Group III) participants. Subgroups were formed in Group I according to the presence of COVID-19 risk factors and comorbidities (diabetes mellitus, cardiovascular disease, and asthma/allergy) and demographic data. RESULTS: Seropositivity rates were 95.5, 100, and 89.3% for Groups I, II, and III, respectively. IgG antibody levels were found significantly higher in the group between the ages of 20–30 in group I compared to those aged 31–50 and over 50 (both p

Background: The city of Manaus, Brazil, has seen two collapses of the health system due to the COVID-19 pandemic. We report anti-SARS-CoV-2 nucleocapsid IgG antibody seroconversion rates and associated risk factors in Manaus residents before the second wave of the epidemic in Brazil. Methods: A convenience sample of adult (aged ≥18 years) residents of Manaus was recruited through online and university website advertising into the DETECTCoV-19 study cohort. The current analysis of seroconversion included a subgroup of DETECTCoV-19 participants who had at least two serum sample collections separated by at least 4 weeks between Aug 19 and Oct 2, 2020 (visit 1), and Oct 19 and Nov 27, 2020 (visit 2). Those who reported (or had no data on) having a COVID-19 diagnosis before visit 1, and who were positive for anti-SARS-CoV-2 nucleocapsid IgG antibodies at visit 1 were excluded. Using an in-house ELISA, the reactivity index (RI; calculated as the optical density ratio of the sample to the negative control) for serum anti-SARS-CoV-2 nucleocapsid IgG antibodies was measured at both visits. We calculated the incidence of seroconversion (defined as RI values ≤1·5 at visit 1 and ≥1·5 at visit 2, and a ratio >2 between the visit 2 and visit 1 RI values) during the study period, as well as incidence rate ratios (IRRs) through cluster-corrected and adjusted Poisson regression models to analyse associations between seroconversion and variables related to sociodemographic characteristics, health access, comorbidities, COVID-19 exposure, protective behaviours, and symptoms. Findings: 2496 DETECTCoV-19 cohort participants returned for a follow-up visit between Oct 19 and Nov 27, 2020, of whom 204 reported having COVID-19 before the first visit and 24 had no data regarding previous disease status. 559 participants were seropositive for anti-SARS-CoV-2 nucleocapsid IgG antibodies at baseline. Of the remaining 1709 participants who were seronegative at baseline, 71 did not meet the criteria for seroconversion and were excluded from the analyses. Among the remaining 1638 participants who were seronegative at baseline, 214 showed seroconversion at visit 2. The seroconversion incidence was 13·06% (95% CI 11·52–14·79) overall and 6·78% (5·61–8·10) for symptomatic seroconversion, over a median follow-up period of 57 days (IQR 54–61). 48·1% of seroconversion events were estimated to be asymptomatic. The sample had higher proportions of affluent and higher-educated people than those reported for the Manaus city population. In the fully adjusted and corrected model, risk factors for seroconversion before visit 2 were having a COVID-19 case in the household (IRR 1·49 [95% CI 1·21–1·83]), not wearing a mask during contact with a person with COVID-19 (1·25 [1·09–1·45]), relaxation of physical distancing (1·31 [1·05–1·64]), and having flu-like symptoms (1·79 [1·23–2·59]) or a COVID-19 diagnosis (3·57 [2·27–5·63]) between the first and second visits, whereas working remotely was associated with lower incidence (0·74 [0·56–0·97]). Interpretation: An intense infection transmission period preceded the second wave of COVID-19 in Manaus. Several modifiable behaviours increased the risk of seroconversion, including non-compliance with non-pharmaceutical interventions measures such as not wearing a mask during contact, relaxation of protective measures, and non-remote working. Increased testing in high-transmission areas is needed to provide timely information about ongoing transmission and aid appropriate implementation of transmission mitigation measures. Funding: Ministry of Education, Brazil; Fundação de Amparo à Pesquisa do Estado do Amazonas; Pan American Health Organization (PAHO)/WHO. World Health Organization Revisión por pares

Zhiming Zhao,1 Huiwen Jin,1 Yang Yin,1 Yanwei Hou,1 Jingyan Wang,1 Chunling Tang,2 Jun Fu1 1Health Center of Screening and Prevention of Diseases, The First Affiliated Hospital of Harbin Medical University, Harbin, 150001, Heilongjiang, People’s Republic of China; 2Department of Psychiatry, The First Affiliated Hospital of Harbin Medical University, Harbin, 150001, Heilongjiang, People’s Republic of ChinaCorrespondence: Jun FuHealth Center of Screening and Prevention of Diseases, The First Affiliated Hospital of Harbin Medical University, 23 Youzheng Street, Nangang District, Harbin, 150001, Heilongjiang, People’s Republic of ChinaTel +86 451 85553111Email fujunyk@hotmail.comPurpose: The relationship between food allergy caused by food specific IgG antibodies and migraine has received increased attention in recent years. Here, we aimed to evaluate the effects of food specific IgG antibodies on headache, gastrointestinal symptoms, anxiety, depression, sleep disorders, dermatosis, and serum inflammatory cytokines in migraine patients, and to quantitatively assess the effect of IgG levels on the severity of headache and its comorbidities.Methods: Of 89 migraine patients, those who had one or more food specific IgG antibodies ≥ 50 U/mL were classified into the IgG positive group, which was then further divided into subgroups based on differing numbers of food allergens. All other subjects were classified into the IgG negative group. We compared the frequency and severity of migraine, anxiety, depression, sleep disorders, dermatosis, and inflammatory cytokines between groups. A regression model was performed to further assess the effect of overall positive IgG concentration and the mediation effect of inflammatory cytokines.Results: Participants in the positive IgG group (n = 67) were more likely to have longer time elapsed since diagnosis, more frequent and severe migraine, a higher risk of developing anxiety and gastrointestinal symptoms, along with higher IL-6 and TNF-α. Subgroups with more food allergens generally had worse conditions as well. After adjusting for the inflammatory cytokines, the effect of IgG was reduced.Conclusion: Migraine patients with positive food specific IgG antibodies had worse migraine, anxiety, and gastrointestinal symptoms. Inflammatory cytokines partially mediate the causal pathway between food specific IgG antibodies, migraine, and migraine comorbidities.Keywords: migraine, food, immunoglobulin G antibody, gastrointestinal symptoms, anxiety, interleukin-6, tumor necrosis factor- &#x03B1

Background: We aimed to determine the prevalence of Alveolar echinococcusis using ELISA in our region, to perform the specific differentiation of species by using the Western Blott method, to diagnose and treat this disease effectively in early periods, and to inform the patients about the results quickly. Methods: From the provinces of Erzurum, Kars, Ardahan, Iğdır, Ağrı and Erzincan in the Eastern Anatolia Region, Turkey in August-September 2017, blood samples were provided from 305 participants (volunteer patients and their relatives), including 151 females (49.50%), whose ages ranged between 6-85 yr and were diagnosed as Alveolar echinococcosis (AE) and operated in concerned clinics. Results: EIgG ELISA was determined as positive in 29 (9.5%) participants, including 17 (11.3%) females and 12 (7.8%) males. In addition, Em2-Em18 ELISA was also determined as positive in 15 (4.9%) participants, including 9 (6%) females and 6 (3.9%) males. Tweleve (3.94 %) of these findings were observed as positive in terms of both tests. Through the verification done by Anti-EWB IgG, Echinococcus multilocularis (EM) was identified in 7 (21.9%) of the female participants, E. granulosus (EG) in 1 (3.1%), and both parasites in 2 (6.2%). For male participants, EM was determined in 3 (9.3%) of them, EG in 1 (3.1%), and both parasites in 1 (3.1%). Conclusion: AE continues to threaten public health in the region. In families where AE is detected positive, the reason for disease is based on nutrition; thus, it will be proper to check up all family members in the terms of infection. © 2022 Akkas et al. Published by Tehran University of Medical Sciences. Bilimsel Araştırma Projeleri Birimi, İstanbul Teknik Üniversitesi, BAP: 2016-FBE-B09 This study was supported by the Igdir University Rectorate Scientific Studies Support Unit (BAP) Coordinator with Project No: 2016-FBE-B09. We would like to thank the Igdir University Rectorate for their contributions. This study was supported by the Igdir University Rectorate Scientific Studies Support Unit (BAP) Coordinator with Project No: 2016-FBE-B09. We would like to thank the Igdir University Rectorate for their contribu-tions.

Objective: As it is well known that autoimmune diseases can coexist, the association of multiple sclerosis (MS) with other autoimmune diseases has always been a major concern for clinicians. In this study, we aimed to investigate the clinical findings, and the frequency of autoantibodies related to celiac disease in MS and clinically isolated syndrome (CIS). Methods: Anti-gliadin immunoglobulin A and anti-gliadin immunoglobulin G and anti-endomysium immunoglobulin A and anti-endomysium immunoglobulin G antibodies were studied by the indirect immune fluorescence method, anti-tissue transglutaminase immunoglobulin A and anti-tissue transglutaminase immunoglobulin G were studied by enzyme-linked immunosorbent assay. The study included 30 patients with CIS, 50 patients with relapsing–remitting MS (RRMS), 30 patients with progressive MS (PMS) and 42 healthy individuals as the control group. Results: One patient was anti-gliadin immunoglobulin A-positive in the CIS group, four patients in the RRMS group, one patient in the PMS group and two patients in the control group. Four patients were anti-gliadin immunoglobulin G-positive in the CIS group, four patients in the RRMS group, three patients in the PMS group and three patients in the control group. One patient was anti-endomysium immunoglobulin A-positive in the CIS group and two patients in the RRMS group. Two patients were anti-endomysium immunoglobulin G-positive in the CIS group, one patient in the RRMS group and one patient in the PMS group. Three patients were anti-tissue transglutaminase immunoglobulin A-positive in the RRMS group and two patients in the control group. All groups were anti-tissue transglutaminase immunoglobulin G-negative. Although the number of patients with positive antibodies seemed to be higher in MS groups, the difference was not statistically significant between the groups. Conclusion: We observed that celiac antibodies were not more common in MS patients than healthy controls. However, these antibodies are important to suggest gastrointestinal complaints in MS patients. © 2021 Japanese Society for Neuroimmunology

Madariaga virus (MADV) has recently been associated with severe human disease in Panama, where the closely related Venezuelan equine encephalitis virus (VEEV) also circulates. In June 2017, a fatal MADV infection was confirmed in a community of Darien Province. We conducted a cross-sectional outbreak investigation with human and mosquito collections in July 2017, where sera were tested for alphavirus antibodies and viral RNA. In addition, by applying a catalytic, force-of-infection (FOI) statistical model to two serosurveys from Darien Province in 2012 and 2017, we investigated whether endemic or epidemic alphavirus transmission occurred historically. In 2017, MADV and VEEV IgM seroprevalences were 1.6% and 4.4%, respectively; IgG antibody prevalences were MADV: 13.2%, VEEV: 16.8%, Una virus (UNAV): 16.0%, and Mayaro virus: 1.1%. Active viral circulation was not detected. Evidence of MADV and UNAV infection was found near households, raising questions about its vectors and enzootic transmission cycles. Insomnia was associated withMADVand VEEV infections, depression symptoms were associated with MADV, and dizziness with VEEV and UNAV. Force-of-infection analyses suggest endemic alphavirus transmission historically, with recent increased human exposure to MADV and VEEV in Aruza and Mercadeo, respectively. The lack of additional neurological cases suggests that severe MADV and VEEV infections occur only rarely. Our results indicate that over the past five decades, alphavirus infections have occurred at low levels in eastern Panama, but that MADV and VEEV infections have recently increased-potentially during the past decade. Endemic infections and outbreaks of MADV and VEEV appear to differ spatially in some locations of eastern Panama. National Institute for Health Research Revisión por pares

The coronavirus disease 2019 (COVID-19) pandemic has created a global health- and economic crisis. Lifting confinement restriction and resuming to normality depends greatly on COVID-19 immunity screening. Detection of antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which causes COVID-19 by serological methods is important to diagnose a current or resolved infection. In this study, we applied a rapid COVID-19 IgM/IgG antibody test and performed serology assessment of antibody response to SARS-CoV-2. In PCR-confirmed COVID-19 patients (n=45), the total antibody detection rate is 92% in hospitalized patients and 79% in non-hospitalized patients. We also studied antibody response in relation to time after symptom onset and disease severity, and observed an increase in antibody reactivity and distinct distribution patterns of IgM and IgG following disease progression. The total IgM and IgG detection is 63% in patients with < 2 weeks from disease onset; 85% in non-hospitalized patients with > 2 weeks disease duration; and 91% in hospitalized patients with > 2 weeks disease duration. We also compared different blood sample types and suggest a potentially higher sensitivity by serum/plasma comparing with whole blood measurement. To study the specificity of the test, we used 69 sera/plasma samples collected between 2016-2018 prior to the COVID-19 pandemic, and obtained a test specificity of 97%. In summary, our study provides a comprehensive validation of the rapid COVID-19 IgM/IgG serology test, and mapped antibody detection patterns in association with disease progress and hospitalization. Our study supports that the rapid COVID-19 IgM/IgG test may be applied to assess the COVID-19 status both at the individual and at a population level.

Background: There is gobal concern regarding the prognosis of COVID-19 patients requiring care in the Intensive Care Unit (ICU). The aim of this study is to report the demographics, clinical features, comorbidities, imaging findings, and prognosis among critically ill patients with COVID-19 in the ICU. Methods: This retrospective study included patients with laboratory-confirmed COVID-19 infection or clinical and radiological confirmed COVID-19 infection who were admitted to adult ICUs between March 18 and April 22, 2020. Demographic data. the recent exposure history, clinical symptoms. laboratory findings and comorbidities were recorded. Acute Physiology and Chronic Health Evaluation II (APACHE II) and Sequential Organ Failure Assessment (SOFA) scores were calculated. as well as mechanical ventilation parameters and blood gas results. Results: Twenty-four adult patients were admitted to the ICU with laboratory-confirmed COVID-19 (n = 15) or clinical and radiological confirmed COVID-19 (n = 9). One or more comorbidities were detected in 22/24 of the patients. All patients had abnormal radiography imaging on admission. Twenty patients had bilateral ground-glass pacification on computerized tomography (CT) scan. Almost all patients (23/24) underwent invasive mechanical ventilation therapy. Three patients underwent noninvasive mechanical ventilation. Ten patients died. The mean length of ICU stay in patients who died was 9.6 +/- 9 days (2-18 days). The mean length of ICU stay of the four patients who were discharged from the ICU to the floor was 17 +/- 12.9 days. The mean length of ICU stay of patients still in the ICU was (n =10) was 13.36 +/- 10.92 days. Conclusion: The vast majority of patients admitted to the ICU with the diagnosis of COVID-I 9 have multiple co-morbidities. require ventilator support, and experience a high mortality rate. C1 [Sungurtekin, Hulya; Arslan, Ulku; Ozgen, Cansu; Kahramanoglu, Mithat; Erbay, Hakan; Atalay, Habip; Karaduman, Simay] Pamukkale Univ, Dept Anesthesiol & Reanimat, Crit Care Unit, Denizli, Turkey. [Akbudak, Ismail Hakki] Pamukkale Univ, Dept Internal Med, Denizli, Turkey. [Caliskan, Ahmet] Pamukkale Univ, Dept Med Microbiol, Denizli, Turkey.

Purpose: To determine if autonomic symptoms are associated with previous Zika virus infection. Methods: Case–control study including 35 patients with Zika virus infection without evidence of neurological disease and 105 controls. Symptoms of autonomic dysfunction were assessed with the composite autonomic symptom scale 31 (COMPASS-31). Results: Patients with previous Zika virus infection had significantly higher COMPASS-31 score than controls regardless of age and sex (p = 0.007). The main drivers for the higher scores where orthostatic intolerance (p = 0.003), secretomotor (p = 0.04) and bladder symptoms (p less than 0.001). Conclusion: Zika virus infection is associated with autonomic dysfunction. The mechanisms remain to be elucidated. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature.

SUMMARYChagas disease is a complex zoonosis that affects around 8 million people worldwide. This pathology is caused byTrypanosoma cruzi, a kinetoplastid parasite that shows tremendous genetic diversity evinced in six distinct Discrete Typing Units (TcI-TcVI) including a recent genotype named as TcBat and associated with anthropogenic bats. TcI presents a broad geographical distribution and has been associated with chronic cardiomyopathy. Recent phylogenetic studies suggest the existence of two genotypes (Domestic (TcIDom) and sylvatic TcI) within TcI. The understanding of the course of the infection in different mouse models by these two genotypes is not yet known. Therefore, we infected 126 animals (ICR-CD1, National Institute of Health (NIH) and Balb/c) with two TcIDomstrains and one sylvatic strain for a follow-up period of 60 days. We quantified the parasitaemia, immune response and histopathology observing that the maximum day of parasitaemia was achieved at day 21 post-infection. Domestic strains showed higher parasitaemia than the sylvatic strain in the three mouse models; however in the survival curves Balb/c mice were less susceptible to infection compared with NIH and ICR-CD1. Our results suggest that the genetic background plays a fundamental role in the natural history of the infection and the sympatric TcI genotypes have relevant implications in disease pathogenesis.

Porcine cysticercosis is an endemic parasitic disease caused by infection with Taenia solium that is found predominantly in developing countries. In order to aid in the development of simple diagnostic approaches, identification and characterization of potential new antigens for immunodiagnostic purposes is desired. The cysteine protease family has previously been found to have important immunodiagnostic properties. These proteases are expressed as zymogens which contain a signal peptide, pro-peptide, and an active domain. Subsequent catalytic cleavage of the pro-peptide converts these zymogens into enzymes. With the use of bioinformatic tools we identified an active domain of a novel cathepsin L-like cysteine protease (TsolCL) in the T. solium genome. The TsolCL gene includes 705 nucleotides (nt) within a single intron and a 633 nt exonic sequence encoding an active protein of 211 amino acids. Sequence alignment and phylogenetic analysis suggest that the TsolCL gene is closely related to genes found in Echinoccocus granulosus and E. multiloculars. In addition, TsolCL was found to have a 61.9%–99.0% similarity to other cathepsin L proteins found in other helminths and mammals. We cloned, expressed, purified, and characterized the recombinant active TsolCL (27 kDa) using the baculovirus-insect cell expression system. TsolCL showed cysteine protease enzymatic activity with the capacity to hydrolyze the Z-Phe-Arg-AMC substrate as well as bovine serum albumin. However, TsolCL was not able to hydrolyze human immunoglobulin. In addition, TsolCL has cathepsin L conserved amino acid residues in the catalytic site (Gln8, Cys14, His159, Asn179 and Trp181) and the motif GCNGG. Using ELISA, TsolCL was able to distinguish circulating IgG antibodies between healthy animals and naturally infected pigs with cysticercosis, showing a moderate sensitivity of 83.33% (40/48; 95% CI: [69.8%–92.5 %]), and a specificity of 83.78% (31/37; 95% CI: [67.9%–93.8%]). In conclusion, a novel cathepsin L-like cysteine protease from a T. solium metacestode was expressed successfully in Baculovirus system and was evaluated as a candidate antigen to diagnose porcine cysticercosis using the ELISA immunoassay.

Cystic echinococcosis (CE) is a parasitic zoonosis caused by the larval stage of the tapeworm Echinococcus granulosus. Detection of the adult stage in the canine definitive host is essential for estimating infection rates, surveillance and monitoring of CE control programs. This study sought to develop and validate a coproantigen sandwich enzyme-linked immunosorbent assay (copro-ELISA), based on antibodies against E. granulosus-soluble membrane antigens (EGMA), that is capable of distinguishing infected and noninfected dogs. Anti-E. granulosus polyclonal immunoglobulin G antibodies were obtained from rabbit antiserum against EGMA. Optimization of the test was performed with 51 positive and 56 negative stool samples of canine echinococcosis. Specificity, sensitivity, cross-reactivity, intra- and inter-assay precision, and over time detection were evaluated. According to the receiver operating characteristic analysis, the diagnostic sensitivity and specificity were 96.1% (CI: 85.9-99.6) and 98.2% (CI: 89.5-100), respectively. Negative and positive predictive values were 96.5% (CI: 91.7-100) and 98% (CI: 94.1-100), respectively. No cross-reactivity with Taenia hydatigena, Dipylidium caninum, or Toxocara canis was observed. Intra- and inter-assay repeatability showed values of less than 15% of the variation coefficient. The over time detection was from 20 to 27 days postinfection with E. granulosus. The copro-ELISA based on EGMA detection offers a simplified in-house development of diagnostic testing. This assay showed high specificity and sensitivity and had no cross-reactivity with other parasites. Further studies and development of this test in a kit format may be useful for the detection of active infection in dogs living in CE endemic regions.

Objective: Systemic lupus erythematosus (SLE) is a systemic autoimmune disease with varied morbidity and mortality. We assessed clinical presentations, autoantibody specificities and therapeutic interventions in Native American (NA) patients with SLE. Methods: Patients with SLE meeting 1997 American College of Rheumatology classification criteria (n=3148) were enrolled between 1992 and 2010 in the multiethnic, cross-sectional Lupus Family Registry and Repository. Clinical, demographic and therapeutic information were extracted from medical records using a standardised form and formalised training. Autoantibodies were assessed by indirect immunofluorescence (antinuclear antibodies (ANA) and antidouble-stranded DNA), precipitin (ENA) and ELISA (IgG and IgM anticardiolipins). Results: NA patients met SLE classification at a younger age (29.89±12.3 years) than European Americans (EA; 32.02±12.87, P=0.0157) and a similar age to African-Americans (AAs) and Hispanics (HIS). More NA patients had concurrent rheumatic diseases or symptoms, such as Raynaud's phenomenon, interstitial lung disease, Sjögren's syndrome and systemic sclerosis. Compared with EAs, NAs were more likely to have high-titre ANA (≥1:3240; P

Background: The serological diagnostic methods currently available for mucocutaneous leishmaniasis (MCL) lack specificity when complete parasites are used; however, such specificity increases when protein fractions are used. Ribosomal proteins have been reported to induce antibodies in animal and humans infected with the parasite, making them a worth candidate to assess its diagnosis potential. Objective: This study was thus aimed at evaluating synthetic peptides derived from Leishmania braziliensis ribosomal proteins S25 and S5 as antigen candidates for diagnosing MCL by ELISA Methods: It was used 8 and 13 peptides derived from ribosomal proteins 25 and S5 respectively as antigens in order to detect IgG antibodies by ELISA in people with active MCL, Chagas disease (CH) and autoimmune disease (AID). Results: 4 of these 21 peptides (P4, P6, P19 and P21) had the greatest sensitivity (21.7%, 13.04%, 20% and 20%, respectively) as well as having 95%, 100%, 100% and 82.5% specificity, respectively. Conclusion: The study revealed the limited usefulness of the peptides being studied as a diagnostic tool in the conditions used here, because its low sensitivity, but it is worth highlighting that the use of peptides as antigen in the serodiagnosis of MCL may overcome the cross reaction presented with other antigens, thus avoiding false positives.

We have focused on the epidemiology and immunobiology of Zika virus (ZIKV) infection and factors associated with the development of Guillain-Barré syndrome (GBS) and other neurological syndromes in Cúcuta, the capital of North Santander department, Colombia. Data of patients with ZIKV disease reported to the national population-based surveillance system were used to calculate the basic reproduction number (R0) and the attack rates (ARs) as well as to develop epidemiological maps. Patients with neurological syndromes were contacted and their diagnoses were confirmed. A case-control study in which 29 patients with GBS associated with ZIKV compared with 74-matched control patients with ZIKV infection alone was undertaken. Antibodies against arboviruses and other infections that may trigger GBS were evaluated. The estimated value of R0 ranged between 2.68 (95% CI 2.54–2.67) to 4.57 (95% CI 4.18–5.01). The sex-specific ARs were 1306 per 100,000 females, and 552 per 100,000 males. A non-linear interaction between age and gender on the ARs was observed. The incidence of GBS in Cúcuta increased 4.41 times secondary to ZIKV infection. The lag time between ZIKV infection and neurological symptoms was 7 days (interquartile range 2–14.5). Patients with GBS appeared to represent a lower socioeconomic status and were living near to environmentally contaminated areas. All GBS patients were positive for IgG antibodies against both ZIKV and Dengue virus, and 69% were positive for Chikungunya virus. Noteworthy, GBS was associated with a previous infection with M. pneumoniae (OR: 3.95; 95% CI 1.44–13.01; p = 0.006). No differences in antibody levels against C. jejuni, Epstein-Barr virus and cytomegalovirus were observed. High rates of cranial nerves involvement and dysautonomia were present in 82% and 75.9%, respectively. Intensive care unit (ICU) admission was necessary in 69% of the GBS patients. Most of the patients disclosed a high disability condition (Hughes grade 4). Dysautonomia was the main risk factor of poor GBS prognosis (i.e., ICU admission and disability). Thirteen patients were diagnosed with other neurological syndromes different to GBS (6 with transverse myelitis, 3 with encephalitis, 3 with peripheral facial palsy and one with thoraco-lumbosacral myelopathy). Our data confirm an increased transmission of ZIKV in Cúcuta, and provide support to the view that severe neurological syndromes are related to ZIKV disease. The complex ways by which previous infections and socioeconomic status interact to increase the risk of GBS in people infected by ZIKV should be further investigated. © 2016 The Authors

Background Identification of chronic Pseudomonas aeruginosa (PA) infection is important in the management of bronchiectasis, but requires repeated sputum sampling. We hypothesized that serum anti-PA IgG antibodies could diagnose chronic PA infection at a single visit. Methods Clinically stable bronchiectasis patients were studied prospectively. Chronic PA infection was defined as 2 or more positive sputum samples at least 3 months apart and/or failure to clear PA following eradication treatment. Baseline serum anti-PA IgG was determined by a validated ELISA kit. Results A total of 408 patients were included. Sixty of them (14.7%) had chronic PA infection and had higher anti-PA IgG levels (median 6.2 vs. 1.3 units, p

Aim: Hepatitis A can be prevented by vaccination. The aim of this study was to determine seropositivity for hepatitis A before vaccination in healthy children 12 and 24 months of age and compare seroconversion rates after vaccination between these 2 groups. Materials and methods: Forty-nine children aged 1 year (Group 1) and 51 children aged 2 years (Group 2) were included in the study. Inactive hepatitis A vaccine (Avaxim, 80 antigenic subtypes, 0.5 mL) were administered to every child in 2 doses, 6 months apart. Anti-hepatitis A virus (HAV) IgG and IgM antibodies were detected by Architect HAVAb-IgG and HAVAb-IgM (Abbott, Wiesbaden, Germany) test kits. Results: Nine percent of the children were seropositive for anti-HAV IgG before vaccination. The seroconversion rate at 2 weeks was 34% and 44% in Group 1 and Group 2, respectively. At 4 weeks the seroconversion rate was 87.7% and 90.1% in Group 1 and Group 2, respectively. All of the children who completed the vaccination program were seropositive at 28 weeks (after the second dose). No serious adverse reaction was observed in any of the children. Conclusion: It was determined that Avaxim, including 80 antigen units, is safe and immunogenic in healthy children 12 and 24 months of age.

Background Helicobacter pylori is associated with gastrointestinal diseases such as gastritis, peptic ulcers, malignancy and lymphoma, and extra-gastrointestinal conditions. H. pylori infection is negatively associated with children's growth. Chronic inflammation of the stomach that results in the loss of appetite and, dysregulation of neuroendocrine hormones such as leptin, and ghrelin are the probable reasons of this negative association. The objective of this study is to determine the serum levels of leptin, ghrelin, and IGF-1 in H. pylori-infected children and their relations with growth. Materials and methods A hundred and sixty-one school children aged between 6 and 14 years were selected randomly from five primary schools representing a cross section of population. Demographic and sociocultural characteristics, and anthropometric measurements were recorded. Serum H. pylori IgG, insulin-like growth factor-1, leptin, and ghrelin levels were measured in all children. The children were grouped according to the nutritional status and Helicobacter pylori seropositivity. Nutritional indices were compared among groups in association with serum leptin, ghrelin, and insulin-like growth factor-1 levels. Results H. pylori IgG positivity was found in 34.2%, and 14.9% of children were malnourished. H. pylori seropositivity was significantly higher in older ages (10.32 ± 2.26 vs 9.53 ± 2.36 years, p = .036), and body weight and height Z scores were significantly lower in H. pylori-seropositive children (−0.33 ± 1.08 vs 0.04 ± 1.26, p = .044 and 0.13 ± 0.92 vs 0.23 ± 0.91, p = .018 respectively). H. pylori seropositivity was found to be an independent risk factor for shorter body height (p = .01). Serum leptin, ghrelin, and IGF-1 levels were not associated with H. pylori IgG seropositivity (0.35 vs 0.55 ng/mL, p = .3; 3267.4 ± 753.0 vs 2808.3 ± 911.4 pg/mL, p = .06; 470 ± 176 vs 521 ± 179 ng/mL, p = .32, respectively). Conclusions Children infected with H. pylori are prone to short stature. This effect seems to be independent of neuroendocrine hormones.

The guinea pig (Cavia porcellus) is a natural reservoir for Trypanosoma cruzi but has seldom been used as an experimental infection model. We developed a guinea pig infection model for acute and chronic Chagas disease. Seventy-two guinea pigs were inoculated intradermally with 10(4) trypomastigotes of T. cruzi strain Y (experimental group); 18 guinea pigs were used as control group. Eight animals from the experimental group and two from the control group were sacrificed 5, 15, 20, 25, 40, 55, 115, 165, and 365 days after inoculation. During the acute phase (15 to 55 days), we observed parasitemia (with a peak on day 20) and positive IgM and IgG Western blots with anti-shed acute-phase antigen bands. The cardiac tissue showed vasculitis, necrosis (on days 40 to 55), moderate to severe inflammation, and abundant amastigote nests. Smaller numbers of amastigote nests were also present in kidney, brain, and other organs. In the early chronic phase (115 to 165 days), parasitemia disappeared and anti-T. cruzi IgG antibodies were still detectable. In cardiac tissue, the number of amastigote nests and the grade of inflammation decreased. In the chronic phase (365 days), the cardiac tissue showed vasculitis and fibrosis; detectable parasite DNA was associated with higher grades of inflammation. The experimental T. cruzi infection model in guinea pigs shows kinetics and pathologic changes similar to those of the human disease.

The high prevalence of both Helicobacter.pylori infection and coronary atherosclerosis in our country prompted us to assess the probable association between both conditions. This cross-sectional study recruited 153 patients scheduled to undergo coronary artery angiography. Patients were divided into two groups on the basis of coronary angiography results. Sixty-nine patients had coronary atherosclerosis and the 84 remaining patients were normal. Characteristics and pre-angiographic serum levels of triglyceride, low-density lipoprotein cholesterol, high-density lipoprotein, and Helicobacter.pylori IgG antibody were assessed in the patients and compared between the groups. Helicobacter.pylori infection occurred in 88 (57.51%) patients: 40 (58%) in the atherosclerotic group and 48 (57.1%) in the control group with no significant differences (P=0.918). Our multivariable analysis revealed that Helicobacter.pylori infection was not an independent predictive factor for coronary artery disease (P =0.915). Also, the prevalence of atherosclerosis risk factors with respect to the seropositive and seronegative Helicobacter.pylori infection was assessed in the case group, which showed no significant difference. Furthermore, the prevalence of seropositive Helicobacter.pylori infection in terms of the number of diseased coronary vessels was evaluated, this demonstrated no significant association between the number of the diseased vessels and Helicobacter.pylori infection. This study demonstrated that Helicobacter.pylori infection was not an independent predictive factor of atherosclerosis.

© 2018 The Author(s) Fragment crystallizable (Fc) region of immunoglobulin G (IgG) antibody binds to specific Fc receptors (FcγRs) to control antibody effector functions. Currently, engineered specific Fc-FcγR interactions are validated with a static conformation derived from the crystal structure. However, computational evidence suggests that the conformational variability of Fcs plays an important role in receptor recognition. Here we elucidate Fc flexibility of IgG1, IgG2, and IgG1 Fc with mutations (M255Y/S257T/T259E) in solution by small-angle X-ray scattering (SAXS). Measured SAXS profiles and experimental parameters show variations in flexibility between Fc isotypes. We develop and apply a modeling tool for an accurate conformational sampling of Fcs followed by SAXS fitting. Revealed conformational variability of the CH2 domain as low as 10 Å in displacement, illustrates the power of the atomistic modeling combined with SAXS. This inexpensive SAXS-based approach offers to improve the engineering of antibodies for tailoring Fc receptor interactions through altering and measuring Fc flexibility.

There is an increasing amount of evidence which links the pathogenesis of irritable bowel syndrome (IBS) with food IgG hyperreactivity. Some authors have suggested that food IgG hyperreactivity could be also involved in the pathophysiology of major depressive disorder (MDD). The aim of this study was to compare levels of serum IgG against 39 selected food antigens between three groups of participants: patients with MDD (MDD group), patients with IBS (IBS group) and healthy controls (HC group). The study included 65 participants (22 in the MDD group, 22 in the IBS group and 21 in the HC group). Serum IgG levels were examined using enzyme-linked immunosorbent assay (ELISA). Medical records, clinical data and laboratory results were collected for the analysis. IgG food hyperreactivity (interpreted as an average of levels of IgG antibodies above 7.5 µg/mL) was detected in 28 (43%) participants, including 14 (64%) from the MDD group, ten (46%) from the IBS group and four (19%) from the HC group. We found differences between extreme IgG levels in MDD versus HC groups and in IBS versus HC groups. Patients with MDD had significantly higher serum levels of total IgG antibodies and IgG against celery, garlic and gluten compared with healthy controls. The MDD group also had higher serum IgG levels against gluten compared with the IBS group. Our results suggest dissimilarity in immune responses against food proteins between the examined groups, with the highest immunoreactivity in the MDD group. Further studies are needed to repeat and confirm these results in bigger cohorts and also examine clinical utility of IgG-based elimination diet in patients with MDD and IBS.

In this study, human sera reactivity against nine peptides derived from the Toxoplasma gondii P30 protein was assessed by ELISA in patients with different clinical forms of toxoplasmosis. Same as has been reported in mice, sera from congenital, ocular and chronic asymptomatic toxoplasmosis patients recognized more strongly peptides from the protein's carboxy-terminus, being peptide 2017 (amino acids 301-320) the one most strongly recognized by sera from patients with ocular toxoplasmosis. Serum samples collected from 13 patients without ocular infection, 13 with inactive chorioretinal scars, 6 with active ocular infection and 10 seronegative individuals were then screened for anti-2017 IgG. Peptide 2017 was recognized by all patients' samples but not by sera from T. gondii-seronegative individuals. No statistically significant differences were found between the absorbance levels of groups with and without lesions or with active or inactive ocular lesions, as determined by ANOVA. © 2009 Elsevier Inc. All rights reserved.

Epidemiological studies have been conducted to better understand the dynamics of American Cutaneous Leishmaniasis (ACL) in the Amazon region where distinct species of Leishmania circulate. In endemic areas, the optimal diagnosis must be made in the earlier clinical presentation to avoid the complications of chronic disease. The scarcity of financial support, laboratory infrastructure and trained persons are the major obstacles in this reality. This paper describes the result of performing different diagnostic methods for ACL in Amazonas State between the years 2010 and 2011. The tests used were the intradermal skin test (Montenegro's skin test), ELISA (Enzyme-Linked Immunosorbent Assay), direct examination, culture isolation and identification of Leishmania species. A total of 38 suspected human cases of ACL were diagnosed by different methods, of which 71.0% (n = 27) were positive by direct examination, 75.6% (n = 28) had positivity in the culture isolates and, of these, 54.0% (n = 19) had infection with Leishmania (Viannia) guyanensis. The positivity of the intradermal skin test with the leishmanin solution was observed in 77.0% of cases analyzed and the serology with detection of IgG and IgM showed the presence of antibodies in 100% of exams realized results, showing variation in the titles of antibodies. The success of Leishmaniasis treatment depends on an effective and early diagnosis. Parasitological diagnosis is highly specific, but sensitivity is subject to variation because the tissue distribution of parasites generally is not homogeneous and depends on the specie of parasite. Moreover, parasitological tests require invasive procedures and depend on restrictive conditions for the collection of biological sample, which limit their use in large-scale for epidemiological studies. ELISA has been the most widely used serological method for the diagnosis of Visceral Leishmaniasis (VL) as it is easy to perform and has a low cost. However, flaws in specificity are observed in the diagnosis of cutaneous leishmaniasis. Actually the diagnosis needs to be done as an associated methods depending on the question to be solved. © 2016 Elsevier Inc.

An outbreak of Guillain-Barré syndrome (GBS), subsequent to Campylobacter jejuni enteritis, occurred in China in 2007. Serum anti-ganglioside antibodies were measured in GBS patients and controls. Genome sequencing was used to determine the phylogenetic relationship among three C. jejuni strains from a patient with GBS (ICDCCJ07001), a patient with gastroenteritis (ICDCCJ07002) and a healthy carrier (ICDCCJ07004), which were all associated with the outbreak. The ganglioside-like structures of the lipo-oligosaccharides of these strains were determined by mass spectrometry. Seventeen (53%) of the GBS patients had anti-GT1a IgG antibodies. GT1a mimicry was found in the lipo-oligosaccharides of strain ICDCCJ07002 and ICDCCJ07004; but a combination of GM3/GD3 mimics was observed in ICDCCJ07001, although this patient had anti-GT1a IgG antibodies. A single-base deletion in a glycosyltransferase gene caused the absence of GT1a mimicry in ICDCCJ07001. The phylogenetic tree showed that ICDCCJ07002 and ICDCCJ07004 were genetically closer to each other than to ICDCCJ07001. C. jejuni, bearing a GT1a-like lipo-oligosaccharide, might have caused the GBS outbreak and the loss of GT1a mimicry may have helped ICDCCJ07001 to survive in the host.

Background: Celiac disease (CD) is an immune-mediated enteropathy triggered by the ingestion of gluten in susceptible individuals, and its prevalence varies depending on the studied population. Given that information on CD in Latin America is scarce, we aimed to investigate the prevalence of CD in this region of the world through a systematic review and meta-analysis. Methods and Findings: This was a two-phase study. First, a cross-sectional analysis from 981 individuals of the Colombian population was made. Second, a systematic review and meta-regression analysis were performed following the Preferred Reporting Items for Systematic Meta- Analyses (PRISMA) guidelines. Our results disclosed a lack of celiac autoimmunity in the studied Colombian population (i.e., anti-tissue transglutaminase (tTG) and IgA anti-endomysium (EMA)). In the systematic review, 72 studies were considered. The estimated prevalence of CD in Latin Americans ranged between 0.46%and 0.64%. The prevalence of CD in firstdegree relatives of CD probands was 5.5%. The coexistence of CD and type 1 diabetes mellitus varied from 4.6% to 8.7%, depending on the diagnosis methods (i.e., autoantibodies and/or biopsies). Conclusions: Although CD seems to be a rare condition in Colombians; the general prevalence of the disease in Latin Americans seemingly corresponds to a similar scenario observed in Europeans. © 2015 Parra-Medina et al.