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89 result(s) for "Butt, Julia"
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Helicobacter pylori and colorectal cancer—A bacterium going abroad?
Besides causing gastric cancer, which was officially acknowledged by the World Health Organization in 1994 [3], the presence of H. pylori has been associated with other diseases as well. Information on whether persistent infection was a consequence of antibiotic resistance, noncompliance to the applied antibiotic treatment, or reinfection during the study course was not further specified in the publication. [...]it would have been interesting to further define whether persistent H. pylori infection alone or together with associated epithelial damage in the stomach—such as atrophic gastritis, intestinal metaplasia, dysplasia, or even gastric cancer—was associated with colorectal adenoma incidence. [...]H. pylori infection could be involved in colorectal carcinogenesis by increasing the release of gastrin that may act as a mitogen. [...]H. pylori induces chronic inflammation in the stomach mucosa, thereby also elevating systemically inflammatory responses in the body [65, 66].
Herpesvirus Antibody Response and Occurrence of Symptoms in Acute and Post-Acute COVID-19 Disease
Knowledge about the underlying causes of the individual occurrence of symptoms during acute COVID-19 disease and during the post-acute sequelae of COVID-19 is limited. In a German COVID-19 follow-up study, we assessed whether elevated antibody responses to herpesviruses were associated with symptom occurrence in acute COVID-19 disease (n = 96 participants) and during 20 months of follow-up (n = 62 participants). Serum samples were analyzed for their antibodies to herpes simplex virus (HSV)-1 and -2, Epstein-Barr virus (EBV), and Cytomegalovirus (CMV) using fluorescent bead-based multiplex serology. The association of herpesvirus antibodies with symptom occurrence (fatigue, fever, dyspnea, decrease in taste, concentration problems) was assessed using multivariate logistic regression models. High EBV antibody levels were significantly associated with a more than fourfold increased odds of experiencing fatigue during acute COVID-19 disease and during follow-up. High CMV antibody levels were significantly associated with a more than threefold increased odds of experiencing concentration problems and a decrease in taste during the follow-up. The HSV-1 and -2 antibody levels were not elevated in the individuals that experienced symptoms. In conclusion, our findings indicate that herpesvirus infections, specifically EBV and CMV infections, might play a role in symptom development during acute and post-acute COVID-19 disease. It remains to be elucidated whether the elevated EBV and CMV antibodies determined in our study are indicators of herpesvirus reactivation.
Multiplex serology for Streptobacillus moniliformis and other ‘rat bite fever-like’ microorganisms for seroprevalence studies in rodents
Rat bite fever (RBF) is a zoonotic disease caused primarily by Streptobacillus ( S .) moniliformis . Norway or brown rats ( Rattus [ R. ] norvegicus ) are the natural host for S. moniliformis and carry the bacterium in the nasopharynx without clinical disease. Transmission to humans often occurs through rat bites or scratches, but also through contact with the excreta of infected rats. Although human infections with S. moniliformis occur worldwide, they are rarely diagnosed. For decades, S. moniliformis was the only known member of the genus Streptobacillus . In recent years, however, four additional species were identified, two of which being zoonotic pathogens capable of causing symptoms identical to RBF in humans. The aim of this study was to develop a serological assay covering all known Streptobacillus species. A bead-based multiplex fluorescence immunoassay for S. moniliformis detection has been used for years in routine diagnostics of laboratory rodents. Here, this assay was adapted to enable the detection of antibodies against all currently known Streptobacillus species and tested with sera from experimentally inoculated mice and rats, and with negative sera from laboratory rodents. Using this assay, we broadly examined the prevalence of Streptobacillus spp. reactive antibodies in wild rodents. Transudates from a total of 107 Norway rats, 81 black or roof rats ( Rattus rattus ) and 110 house mice ( Mus musculus ) from different husbandries and wildlife populations within Germany were tested. Antibody prevalences of 41% in R. norvegicus and 83% in R. rattus suggest that Streptobacillus spp. are widespread in wild and captive rats in Germany, whereas wild mice seem to be free of infection. Due to its high throughput capacity and multiplex format, the Streptobacillus multiplex serology is well suited for large seroprevalence studies in rodents and has the potential, after adaptation, for use in humans, thereby allowing for the assessment of Streptobacillus infection risk and risk of RBF.
SARS-CoV-2 antibody and neutralization dynamics among persons with natural- and vaccine-induced exposures
Previous SARS-CoV-2 research indicates that antibody levels and corresponding neutralization potential increase with additional exposures (comprising vaccination or infection), and that hybrid immunity resulting from combined vaccination and natural infection is more robust than either alone. However, it is unclear whether or how antibody levels increase or eventually plateau with repeated exposures and how SARS-CoV-2 exposure differs by sex or other demographic factors. Research regarding the association of antibody production with neutralization potential is also limited. We conducted this analysis within the RESPIRA population-based cohort in Costa Rica to investigate relationships between antibody levels and neutralization potential at increasing exposure levels. We examined immunological profiles from systematically defined single-exposure groups (one vaccine dose or one natural infection), double-exposure groups (two vaccine doses or one vaccine dose following a natural infection), and a triple-exposure group (two vaccine doses following a natural infection). We used a S1-RBD-based serological assay for antibody level detection and a pseudovirion assay for neutralization potential quantification. Using linear regression, we compared antibody levels and pseudoneutralization geometric mean titers between exposure groups. For single exposure groups, one vaccine dose was inferior to natural infection, but a second vaccine dose was superior to natural infection. For double exposure groups, those who were vaccinated once after infection developed higher levels of antibodies and higher neutralization potential compared with those who had only two vaccine doses. We note that peak antibody levels following an exposure may plateau after two exposures while neutralization potential continues to increase with a third exposure dose. Response patterns were comparable in males and females and in sensitivity analyses stratified by age, vaccine type, and pandemic wave. These results provide evidence that SARS-CoV-2 vaccination after COVID infection provides immunological benefit and suggest neutralization potential continues to increase after a second vaccine dose despite plateauing of antibody levels.
Validation of Multiplex Serology detecting human herpesviruses 1-5
Human herpesviruses (HHV) cause a variety of clinically relevant conditions upon primary infection of typically young and immunocompetent hosts. Both primary infection and reactivation after latency can lead to more severe disease, such as encephalitis, congenital defects and cancer. Infections with HHV are also associated with cardiovascular and neurodegenerative disease. However, most of the associations are based on retrospective case-control analyses and well-powered prospective cohort studies are needed for assessing temporality and causality. To enable comprehensive investigations of HHV-related disease etiology in large prospective population-based cohort studies, we developed HHV Multiplex Serology. This methodology represents a low-cost, high-throughput technology that allows simultaneous measurement of specific antibodies against five HHV species: Herpes simplex viruses 1 and 2, Varicella zoster virus, Epstein-Barr virus, and Cytomegalovirus. The newly developed HHV species-specific ('Monoplex') assays were validated against established gold-standard reference assays. The specificity and sensitivity of the HHV species-specific Monoplex Serology assays ranged from 92.3% to 100.0% (median 97.4%) and 91.8% to 98.7% (median 96.6%), respectively. Concordance with reference assays was very high with kappa values ranging from 0.86 to 0.96 (median kappa 0.93). Multiplexing the Monoplex Serology assays resulted in no loss of performance and allows simultaneous detection of antibodies against the 5 HHV species in a high-throughput manner.
Increased Serological Response Against Human Herpesvirus 6A Is Associated With Risk for Multiple Sclerosis
Human herpesvirus (HHV)-6A or HHV-6B involvement in multiple sclerosis (MS) etiology has remained controversial mainly due to the lack of serological methods that can distinguish the two viruses. A novel multiplex serological assay measuring IgG reactivity against the immediate-early protein 1 from HHV-6A (IE1A) and HHV-6B (IE1B) was used in a MS cohort (8,742 persons with MS and 7,215 matched controls), and a pre-MS cohort (478 individuals and 476 matched controls) to investigate this further. The IgG response against IE1A was positively associated with MS (OR = 1.55, = 9 × 10 ), and increased risk of future MS (OR = 2.22, = 2 × 10 ). An interaction was observed between IE1A and Epstein-Barr virus (EBV) antibody responses for MS risk (attributable proportion = 0.24, = 6 × 10 ). In contrast, the IgG response against IE1B was negatively associated with MS (OR = 0.74, = 6 × 10 ). The association did not differ between MS subtypes or vary with severity of disease. The genetic control of HHV-6A/B antibody responses were located to the Human Leukocyte Antigen (HLA) region and the strongest association for IE1A was the DRB1 13:01-DQA1 01:03-DQB1 06:03 haplotype while the main association for IE1B was DRB1 13:02-DQA1 01:02-DQB1 06:04. In conclusion a role for HHV-6A in MS etiology is supported by an increased serological response against HHV-6A IE1 protein, an interaction with EBV, and an association to HLA genes.
Web-Based Application for Reducing Methamphetamine Use Among Aboriginal and Torres Strait Islander People: Randomized Waitlist Controlled Trial
Digital interventions can help to overcome barriers to care, including stigma, geographical distance, and a lack of culturally appropriate treatment options. \"We Can Do This\" is a web-based app that was designed with input from cultural advisors and end users to support Aboriginal and Torres Strait Islander people seeking to stop or reduce their use of methamphetamine and increase psychosocial well-being. This study aimed to evaluate the effectiveness of the \"We Can Do This\" web-based app as a psychosocial treatment for Aboriginal and Torres Strait Islander people who use methamphetamine. The web app was evaluated using a randomized waitlist controlled parallel group trial. Participants were Aboriginal and Torres Strait Islander people aged 16 years or older who self-identified as having used methamphetamine at least weekly for the past 3 months. Participants were randomized on a 1:1 ratio to receive either access to the web-based app for 6 weeks or a waitlist control group. Both groups received access to a website with harm minimization information. The primary outcome was days of methamphetamine use in the past 4 weeks assessed at 1, 2, and 3 months post randomization. Secondary outcomes included severity of methamphetamine dependence (Severity of Dependence Scale [SDS]), psychological distress (Kessler 10 [K10]), help-seeking behavior, and days spent out of role due to methamphetamine use. Participants (N=210) were randomized to receive either access to the web-based app (n=115) or the waitlist control condition (n=95). Follow-up was 63% at 1 month, 57% at 2 months, and 54% at 3 months. There were no significant group differences in days of methamphetamine use in the past 4 weeks at 1 the month (mean difference 0.2 days, 95% CI -1.5 to -2), 2 months (mean difference 0.6 days, 95% CI -1 to 2.4 days) or 3 months (mean difference 1.4 days, 95% CI -0.3 to 3.3 days) follow-up. There were no significant group differences in K10 scores, SDS scores, days out of role, or help-seeking at any of the 3 follow-up timepoints. There was poor adherence to the web-based app, only 20% of participants in the intervention group returned to the web-based app after their initial log-in. Participants cited personal issues and forgetting about the web-based app as the most common reasons for nonadherence. We found poor engagement with this web-based app. The web-based app had no significant effects on methamphetamine use or psychosocial well-being. Poor adherence and low follow-up hindered our ability to accurately evaluate the effectiveness of the web-based app. Future web-based apps for this population need to consider methods to increase participant engagement. Australian New Zealand Clinical Trials Registry ACTRN12619000134123p; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=376088. RR2-10.2196/14084.
Time course and determinants of the antibody response to SARS-CoV-2 in Costa Rica: the RESPIRA study
Antibodies to SARS-CoV-2 are essential for protection or reduction in severity of subsequent disease. We studied antibody responses to spike protein receptor-binding domain (S1-RBD) and nucleocapsid (N) in a population-based sample of COVID-19 cases in Costa Rica. As part of the RESPIRA study, we selected an age-stratified random sample of PCR-confirmed COVID-19 cases diagnosed from March 2020 to July 2021. Antibodies were determined with multiplex serology in 794 unvaccinated subjects diagnosed 3 days to 17 months before recruitment to investigate immune response to natural infection. In addition, neutralizing antibodies were determined in 136 randomly selected participants. We estimated antibody positivity and GMTs by time since diagnosis and explored determinants using multivariate regression. Most participants tested 15-29 days after PCR diagnosis were seropositive for N (90%) and S1-RBD antibodies (96%) and had the highest GMTs for both antibodies. Only 42% of subjects tested one year after infection were seropositive for N antibodies, compared to 97% for S1-RBD. GMTs for neutralizing antibodies peaked 15-89 days after infection and declined but remained positive for 95% of subjects thereafter. In multivariate models, antibodies were significantly higher among men and increased with age and severity of the clinical presentation. The correlation of multiplex and neutralizing antibodies was high (0.72 [95% CI = 0.63-0.79]) and stronger among women. A robust immune response against N and S1-RBD is elicited by COVID-19 a few days after infection. While S1-RBD antibodies are present after > 1 year, N antibodies decline significantly. Antibody levels are higher in men and increase with age and severity of disease. The different immune response patterns by sex warrant further investigation. RESPIRA Study ClinicalTrials.gov ID: NCT04537338 (3 September 2020).
Smoking and Epstein–Barr virus infection in multiple sclerosis development
It is unclear whether smoking interacts with different aspects of Epstein–Barr virus (EBV) infection with regard to multiple sclerosis (MS) risk. We aimed to investigate whether smoking acts synergistically with elevated EBNA-1 antibody levels or infectious mononucleosis (IM) history regarding MS risk. Two Swedish population-based case–control studies were used (6,340 cases and 6,219 matched controls). Subjects with different smoking, EBNA-1 and IM status were compared regarding MS risk, by calculating odds ratios (OR) with 95% confidence intervals (CI) employing logistic regression. Potential interaction on the additive scale was evaluated by calculating the attributable proportion due to interaction (AP). Current and past smokers had higher EBNA-1 antibody levels than never smokers (p < 0.0001). There was an additive interaction between current smoking and high EBNA-1 antibody levels (AP 0.3, 95% CI 0.2–0.4), but not between past smoking and high EBNA-1 antibody levels (AP 0.01, 95% CI − 0.1 to 0.1), with regard to MS risk. An interaction also occurred between current smoking and IM history (AP 0.2, 95% CI 0.004–0.4), but not between past smoking and IM history (AP − 0.06, 95% CI − 0.4 to 0.3). Current smoking increases EBNA-1 antibody levels and acts synergistically with both aspects of EBV infection to increase MS risk, indicating that there is at least one pathway to disease in which both risk factors are involved.
Association of Antibody Responses to Helicobacter pylori Proteins with Colorectal Adenoma and Colorectal Cancer
Helicobacter pylori (H. pylori) has been implicated in colorectal carcinogenesis. Here, the association of immune responses to bacterial exposure with advancing stages of colorectal neoplasia was assessed by multiplex serology. Immunoglobulin (Ig) A and G antibody responses to thirteen proteins of H. pylori were measured by a Luminex-based multiplex assay in plasma from patients with colorectal cancer (CRC, n = 25), advanced adenoma (n = 82), or small polyps (n = 85) and controls (n = 100). Multivariable logistic regression was used to assess the association of bacterial seropositivity with colorectal neoplasia. The threshold for overall seropositivity required subjects to be positive for at least 4 out of the 13 tested antigens. In a cohort subset with matched data (n = 34), H. pylori seropositivity was correlated with bacterial abundance in both neoplastic and matched normal tissue. While no association was found between H. pylori seropositivity and the presence of CRC, IgA seropositivity to CagA was associated with a decreased risk of advanced adenoma (odds ratio, OR = 0.48, 95% confidence intervals, CIs: 0.24–0.96). Regarding IgG, higher antibody responses to HpaA was associated with advanced adenoma occurrence (OR = 2.46, 95% CI: 1.00–6.01), while responses to HP0395, CagA and Catalase were associated with polyp development (OR = 2.65, 95%, CI: 1.31–5.36, OR = 1.83, 95% CI: 1.01–3.32, and OR = 2.16, CI: 1.09–4.29, respectively). Positive correlations were found between H. pylori abundance in the normal mucosa and levels of both the IgA and IgG antibody response to Catalase and VacA antigens (r = 0.48, p < 0.01; r = 0.37, p = 0.04; r = 0.51, p < 0.01; and r = 0.71, p = 0.04, respectively). Conversely, H. pylori abundance was negatively correlated with levels of IgA antibody response to HpaA and with IgG antibody response to HP0231 in the diseased tissue (r = −0.34, p = 0.04 and r = −0.41, p = 0.01, respectively). The association between levels of H. pylori antigens and colorectal neoplasia risk gradually decreased with the adenoma progression, implicating the early activation of the immune response at the polyp stage. Thus, the evaluation of antibody response to certain bacterial antigens may indicate the presence of early-stage colorectal neoplasia. Further studies are needed to clarify the role H. pylori or the immune response to its antigens may have in colorectal carcinogenesis stages.