Search Results (2,150)

Via a One Health approach, this study concomitantly assessed the susceptibility of humans and dogs to Trypanosoma cruzi infections on three islands and in two mainland seashore areas of southern Brazil. Human serum samples were tested using an enzyme-linked immunosorbent assay (ELISA) to detect anti-T. cruzi antibodies, while dog serum samples were tested using indirect fluorescent antibodies in an immunofluorescence assay (IFA). Seropositive human and dog individuals were also tested using quantitative polymerase chain reaction (qPCR) in corresponding blood samples. Overall, 2/304 (0.6%) human and 1/292 dog samples tested seropositive for T. cruzi by ELISA and IFA, respectively, and these cases were also molecularly positive for T. cruzi by qPCR. Although a relatively low positivity rate was observed herein, these cases were likely autochthonous, and the individuals may have been infected as a consequence of isolated events of disturbance in the natural peridomicile areas nearby. Such a disturbance could come in the form of a fire or deforestation event, which can cause stress and parasitemia in wild reservoirs and, consequently, lead to positive triatomines. In conclusion, T. cruzi monitoring should always be conducted in suspicious areas to ensure a Chagas disease-free status over time. Further studies should also consider entomological and wildlife surveillance to fully capture the transmission and spread of T. cruzi on islands and in seashore mainland areas of Brazil and other endemic countries. Full article

Background/Objectives: Anti-p200 pemphigoid is a rare and likely underdiagnosed autoimmune blistering disorder. Laminin γ1 and laminin β4 have been implicated as potential target antigens in its pathogenesis. Recently, a novel indirect immunofluorescence assay targeting anti-laminin β4 antibodies has been developed, demonstrating high sensitivity and specificity, and offering a valuable tool for improved diagnosis. Methods: Of the 451 patients, 21 were selected for further laboratory analysis based on medical records. Sera from 10 patients, which showed a positive direct immunofluorescence (DIF) result and negative results in multiplex enzyme-linked immunosorbent assays (ELISAs) and/or mosaic six-parameter indirect immunofluorescence (IIF) for various autoimmune bullous diseases, were tested for the presence of anti-laminin β4 antibodies. Additionally, sera from 11 patients with positive DIF and positive ELISA for antibodies against BP180 and/or BP230 were analyzed. Results: Among the 10 patients with positive DIF and negative ELISA and/or mosaic six-parameter IIF, 6 sera were positive for anti-laminin β4 antibodies. These patients presented with atypical clinical features. In contrast, all 11 sera from patients with both positive DIF and positive ELISA for BP180 and/or BP230 were negative for anti-laminin β4 antibodies. Conclusions: In patients with a positive DIF result but negative ELISA and/or mosaic six-parameter IIF findings, testing for anti-laminin β4 antibodies should be considered. Furthermore, in cases presenting with atypical clinical features—such as acral distribution of lesions, intense pruritus, or erythematous–edematous plaques—the possibility of anti-p200 pemphigoid should be included in the differential diagnosis. Full article

Background: This study aimed to assess the prevalence of SARS-CoV-2 infection, vaccination, and immune status among a population, both Dentists and University Professors, within a clinical setting at one and at 12 months after COVID-19 vaccination. Methods: A cross-sectional study involving 47 professionals (aged 27–52) was conducted in the University Fernando Pessoa. Participants completed an online survey on SARS-CoV-2 infection status and vaccination, received and provided plasma samples for serological analysis. The protocol was approved by the UFP-Ethics Committee. Anti-S1-RBD SARS-CoV-2 IgM and IgG antibody titration values (AU/mL) were measured, by enzyme-linked-immunosorbent assay (ELISA), with reactive immunoglobulins (Ig) seropositivity for values ≥1 AU/mL. Results: SARS-CoV-2 infection rate increased from 8.5% in July 2021 to 48.9% in June 2022, with 8.5% experiencing reinfection. Vaccination rate was 91.5% by July 2021 and increased slightly to 93.6% by June 2022; 72.3% of the sample received a third dose. IgG seropositivity increased from 91.5% to 95.7% in June 2022. After one-year, significant associations were found between IgG seropositivity and both participant’s age (p = 0.009; <50 years) and vaccine doses (p = 0.003; 1–3 doses) received. Conclusions: SARS-CoV-2 infection rate, vaccination, and IgG seropositivity rates were high and increased over one year. The age and vaccination status were associated with the immunity status at 12th month follow-up. Findings highlight variability in IgG seroprevalence due to multiple influencing factors, which justifies future studies. Full article

Alzheimer’s Disease (AD) is a multifactorial process. Amyloid plaque formation constitutes the main characteristic of the disease. Despite the identification of numerous factors associated with AD, the mechanism remains unclear in several aspects. Disturbances in intestinal and blood–brain barrier (BBB) penetration, observed in AD, may facilitate immunologic response to food-derived antigens. In the present study, antibodies against egg albumin, bovine-casein, and N-Glycolyl-Neuraminic acid (Neu5Gc) were measured in the cerebrospinal fluid (CSF) and serum of the patients using an enzyme-linked immunosorbent assay (ELISA). Zero anti-Neu5Gc and low concentrations of anti-casein antibodies were detected. Increased anti-native egg albumin antibodies were present in the serum of patients of all stages with 65% positivity (p < 0.001) in mild disease and a higher percentage in females (81.9%, p < 0.001). Lower serum positivity to anti-denatured egg albumin antibodies was observed, showing a gradual increase with severity and higher prevalence also in females. In the CSF, anti-native and anti-denatured egg albumin antibodies were mainly observed in severely ill patients with accumulative positivity to either antigen, reaching 61.8% in severe vs. 15% in mild disease (p < 0.001). Increased values were mainly observed in males. Anti-egg albumin antibodies may be implicated in the disease mechanism through sequence/structural similarity with human proteins, mainly serpins, and it would be worth consideration in further investigations and therapeutic strategies. Full article

Although ART leads to viral suppression, people living with HIV (PLWH) still face an increased risk of comorbidities, such as cancer. The HIV-1 Tat protein may contribute to the promotion of chronic inflammation, oxidative stress, and genomic instability. While the presence of anti-Tat antibodies has been associated with slower disease progression, their potential role in modulating DNA damage remains unclear. Assess the effect of anti-Tat antibodies on cytotoxic and DNA damage in PLWH. A cross-sectional study was conducted in 178 PLWH. Serum anti-Tat IgG antibodies were measured using enzyme-linked immunosorbent assay (ELISA). Cytotoxicity and DNA damage were assessed via serum 8-hydroxy-2′-deoxyguanosine (8-OHdG) and nuclear anomalies (Micronucleus cytome assay) in 2000 buccal cells. Statistical significance was considered at p < 0.05. Anti-Tat antibodies were found in 24.2% of participants. Positive individuals had lower CD4+ T cell counts (p = 0.045) and higher levels of pyknosis (p = 0.0001). No differences in 8-OHdG were found, but 8-OHdG correlated positively with CD4+ counts (rho = 0.334, p = 0.006). Pyknosis negatively correlated with CD4+ counts (rho = −0.272, p = 0.027). Anti-Tat antibodies may not prevent DNA damage but could be related to cytotoxic effects in PLWH. Full article

Background: Vaccination effectively reduces the risk of infection, including COVID-19 yet older adults often receive insufficient attention despite their increased vulnerability. The study aimed to correlate serological results with underlying conditions, vaccination status, and COVID-19 history. Methods: This non-interventional, multicenter study aimed to assess vaccination coverage and SARS-CoV-2 antibody levels among residents of eight long-term care facilities (LTCFs) in Southern Poland. Data collection took place between January and June 2022, with 429 participants recruited based on their ability to provide informed consent and their residency in LTCFs. Sociodemographic data, medical history, and COVID-19-related information—including infection history and vaccination status—were collected through surveys. Blood samples were obtained for serological testing using enzyme-linked immunosorbent assays (ELISA) to detect anti-SARS-CoV-2 antibodies. Statistical analysis, including Spearman’s correlation, revealed significant associations between antibody levels and vaccination status, as well as between RT-PCR-confirmed COVID-19 infections and higher antibody titers. Results: Among the seven different qualitative serological, only the Anti-SARS-CoV-2 NCP (IgG) and Anti-SARS-CoV-2 (IgA) tests showed a positive correlation with the Anti-SARS-CoV-2 QuantiVac (IgG) test, which was used as a comparator. A weak correlation was noted with the age of the residents. Conclusions: Our findings suggest that vaccination positively influences antibody responses, underscoring the importance of immunization among LTCF residents. Additionally, certain comorbidities—such as degenerative joint disease and diabetes—showed weak correlations with higher antibody levels. This study provides valuable insights into the humoral immune response to COVID-19 in vulnerable populations residing in LTCFs. Full article

This study elucidates the role of the steroidogenic acute regulatory protein (StAR) in sex steroid hormone dynamics and the gonadal development of the commercially important marine bivalve ark shell Scapharca broughtonii. The sequence of the StAR gene was obtained and verified from the transcriptome of ark shell, then the tissue localization and expression pattern during the gonad development of the StAR gene were detected by in situ hybridization and quantitative real-time PCR, respectively. Additionally, the concentrations of three critical sex steroid hormones (progesterone, testosterone, and estradiol) were measured throughout gonadal development using enzyme-linked immunosorbent assay (ELISA). The results showed that the length of the coding region of StAR was 1446 bp, encoding 481 amino acids. The results of qRT-PCR showed that the expression of the StAR gene varied with gonadal development, increased from the early active stage to the development stage, and decreased from the mature stage to the spent stage. Notably, the expression level in ovaries was higher than that in testes, suggesting the potential involvement of StAR in sex differentiation and gonadal development. Additionally, the results indicated that progesterone, testosterone, and estradiol accounted for 80%, 10%, and 10% of the total hormone content in the gonads, respectively. Correlation analysis revealed a highly significant strong positive correlation between progesterone/estradiol levels and StAR gene expression, demonstrating that StAR serves as a key regulator in sex steroid hormone biosynthesis. These findings provide crucial molecular evidence for StAR-mediated steroidogenesis in bivalve reproduction, offering fundamental insights into invertebrate endocrinology. Full article

Nipah virus (NiV) and Hendra virus (HeV), which both belong to the genus henipavirus, are zoonotic pathogens that cause severe systemic, neurological, and/or respiratory disease in humans and a variety of mammals. Therefore, monitoring viral prevalence in natural reservoirs and rapidly diagnosing cases of henipavirus infection are critical to limiting the spread of these viruses. Current laboratory methods for detecting NiV and HeV include virus isolation, reverse transcription quantitative real-time PCR (RT-qPCR), and antigen detection via an enzyme-linked immunosorbent assay (ELISA), all of which require highly trained personnel and specialized equipment. Here, we describe the development of a point-of-care customized immunochromatographic lateral flow (ILF) assay that uses recombinant human ephrin B2 as a capture ligand on the test line and a NiV-specific monoclonal antibody (mAb) on the conjugate pad to detect NiV and HeV. The ILF assay detects NiV and HeV with a diagnostic specificity of 94.4% and has no cross-reactivity with other viruses. This rapid test may be suitable for field testing and in countries with limited laboratory resources. Full article

Programmed death-ligand 1 (PD-L1) is an immune checkpoint protein. The soluble form of PD-L1 (sPD-L1) and PD-L1 derived from small extracellular vesicles (sEVPD-L1) are promising cancer biomarkers. While sEVPD-L1 in particular may contribute to immune evasion and is associated with a poor prognosis, it exists only in trace amounts, making it difficult to detect using conventional enzyme-linked immunosorbent assay (ELISA) methods. Therefore, we developed an ultrasensitive detection method, TN-cyclon™. The TN-cyclon™ method combines sandwich ELISA with enzyme cycling amplification. We applied TN-cyclon™ to measure recombinant PD-L1 protein and sEVPD-L1 in serum samples from cancer patients and healthy donors. Recombinant PD-L1 protein was measured with an ultrasensitive detection limit of 0.172 pg/mL. In clinical specimens, sEVPD-L1 levels were significantly higher in lung cancer patients than in healthy donors, whereas sPD-L1 levels measured with a conventional ELISA did not differ significantly between groups. Our results demonstrated that the TN-cyclon™ method exhibits a 20-fold increase in sensitivity compared to a conventional ELISA. Although this is a pilot study, our new assay enables the detection of very low concentrations of sEVPD-L1 in serum that can be used to evaluate the predictive and prognostic performance of sEVPD-L1 in lung cancer patients in future studies. Full article

Every year, diarrhoea is responsible for >1 million deaths in children with ages from 0 to 5 years, with rotavirus as the leading cause. The regions most affected lack routine rotavirus diagnosis due to high cost, lack of necessary equipment and shortage of trained-personnel for Enzyme-Link-Immunosorbent-Assay (ELISA) and molecular methods. We report the development and evaluation of a cheap, nanoparticle-based immunoassay for routine machine-free rotavirus diagnosis. In this work, optimal conditions for oxidation of cotton swabs and aldehyde production for kit development was confirmed by Fourier-Transform Infrared Spectroscopy (FTIR). Lactoferrin (LF) needed to bind the virus to the cotton swab was immobilised on activated cotton swabs, followed by the capture of commercial rotavirus antigen on LF-immobilised swabs. This was dipped in coloured nanobeads covalently coupled to rotavirus-group-specific monoclonal antibody for visual rotavirus detection. Subsequently, rotavirus detection by nanoassay, commercial ELISA and quantitative reverse transcription PCR were compared using same set of 186 stool samples and subjected to statistical analyses. Optimal oxidisation condition was observed using 48 mg/mL NaIO₄ in 0.1 M sodium acetate buffer at 35 °C for 9 h. Rotavirus detection was confirmed visually by blue colour retention on swabs after several washings. Sensitivity, specificity, positive-predictive-value and negative-predictive-value of ELISA in rotavirus detection were 60%, 84%, 53% and 88%, respectively, while our immunoassay showed performance at 88%, 94%, 82% and 96%. This immunoassay will provide effective rotavirus public health interventions in low-and-middle-income countries with high morbidity/mortality. Full article

In this review, we aim to provide a comprehensive overview of the roles of fungi in horticultural crops. Their beneficial roles and pathogenic effects are investigated. In addition, the recent advancements in fungal detection and management strategies (especially the use of spectral analysis) are summarized. Beneficial fungi, including plant growth-promoting fungi (PGPF), ectomycorrhizal fungi (ECM), and arbuscular mycorrhizal fungi (AMF), enhance nutrient uptake, promote root and shoot development, improve photosynthetic efficiency, and support plant resilience against biotic and abiotic stresses. Additionally, beneficial fungi contribute to flowering, seed germination, and disease management through biofertilizers, microbial pesticides, and mycoinsecticides. Conversely, pathogenic fungi cause significant diseases affecting roots, stems, leaves, flowers, and fruits, leading to crop yield losses. Advanced spectral analysis techniques, such as Fourier Transform Infrared Spectroscopy (FTIR), Near-Infrared Spectroscopy (NIR), Raman, and Visible and Near-Infrared Spectroscopy (Vis-NIR), alongside traditional methods like Polymerase Chain Reaction (PCR) and Enzyme-Linked Immunosorbent Assay (ELISA), have shown promise in detecting and managing fungal pathogens. Emerging applications of fungi in sustainable agriculture, including biofertilizers and eco-friendly pest management, are discussed, underscoring their potential to enhance crop productivity and mitigate environmental impacts. This review provides a comprehensive understanding of the complex roles of fungi in horticulture and explores innovative detection and management strategies. Full article

Soybean (Glycine max) peptide lunasin exhibits significant cancer-preventive, antioxidant, and hypocholesterolemic effects. This study aimed to identify quantitative trait nucleotides (QTNs) associated with lunasin content and to annotate the candidate genes in the soybean genome. The mapping panel of 144 accessions was gathered from the USDA Soybean Germplasm Collection, encompassing diverse geographical origins and genetic backgrounds, and was genotyped using SoySNP50K iSelect Beadchips. The lunasin content in soybean seeds was measured using the enzyme-linked immunosorbent assay (ELISA) method, with lipid-adjusted soybean flour prepared from seeds obtained from the Germplasm Resource Information Network (GRIN) of USDA-ARS in 2003 and from North Carolina in 2021, respectively. QTNs significantly related to lunasin content in soybean seeds were detected on 15 chromosomes, with LOD scores greater than 3.0, explaining various phenotypic variations identified using the R package mrMLM (v4.0). Significant QTNs on chromosomes 3, 13, 16, 18, and 20 were consistently identified across multiple models as being significantly associated with soybean lunasin content, based on assessment data from two years. Twenty-nine candidate genes were found, with 12 identified in seeds from 2003 and 17 from 2021. Our study is an important effort to understand the genetic basis and functional genes for lunasin production in soybean seeds. Full article

Background: In September 2023, Storm Daniel triggered catastrophic flooding across Thessaly, in central Greece, leading to the deaths of approximately 483,476 animals and heightening concerns about zoonotic diseases, particularly Q fever caused by Coxiella burnetii. Sofades, a municipality in the Karditsa region that is severely impacted by the floods, emerged as a critical area for evaluating the risk of zoonotic disease transmission. This study aimed to determine the seroprevalence status of Coxiella burnetii Phase 1 IgA antibodies among residents in the rural area of Sofades after the Daniel floods. Methods: Serum samples were obtained from a convenient sample of residents with livestock exposure between 1 March and 31 March 2024. Enzyme-linked immunosorbent assay (ELISA) was used to detect Coxiella burnetii Phase 1 IgA antibodies. Descriptive analyses summarized demographic data, and logistic regression was employed to examine the association between gender, age, and positive ELISA results. Results: The overall seroprevalence was 16.66%. Males had a significantly higher positivity rate (28.57%) than females (6.25%). Seropositivity was more frequent among individuals aged 41–80 years, with peak prevalence observed in the 61–80 age group. Conclusions: This cross-sectional study offers a snapshot of Coxiella burnetii exposure in a high-risk rural population post-flood. The slightly higher seroprevalence in Sofades (16.66%) compared to Karditsa (16.1%) suggests limited influence of environmental factors on transmission. Despite limitations in causal inference, the findings highlight the need for enhanced surveillance and targeted public health measures. Longitudinal studies are needed to assess the long-term impact of environmental disasters on Q fever dynamics. Full article

Galactomannan (GM) is a polysaccharide secreted by opportunistic pathogenic fungi of the Aspergillus genus. It is prescribed as a diagnostic biomarker of invasive aspergillosis in immunocompromised patients by the guidelines for diagnosis and management of Aspergillus diseases. It has been shown previously that the measurement of soluble horseradish peroxidase (HRP) using surface-enhanced Raman scattering (SERS) of 2,3-diaminophenazine enzymatic reaction product on silver nanoparticles is largely superior in detection limit compared to colorimetric readout. In this study, a highly sensitive SERS-based HRP measurement protocol was applied to enzyme-linked immunosorbent assay (ELISA) for GM quantification in biological fluids. The detection limit for GM was 4.3 pg per sample, which is one and a half orders of magnitude lower compared to colorimetric detection with o-phenylenediamine as a substrate and five times more sensitive than ELISA using 3,3′,5,5′-tetramethylbenzidine. Full article

Objectives: The durability and breadth of neutralizing antibodies following SARS-CoV-2 mRNA vaccination remain incompletely understood. This study aimed to investigate how longitudinal changes in antibody isotype composition impact neutralization against structurally diverse SARS-CoV-2 variants. Methods: After screening a broader cohort of mRNA-vaccinated sera, time-matched samples collected one month (1 mpv) and three months post-vaccination (3 mpv) were selected for detailed analysis. Neutralization assays against live virus variants, enzyme-linked immunosorbent assays (ELISA), and immunogold electron microscopy were performed to assess antibody titers, isotype levels, and virion morphology. Results: Neutralization titers declined markedly at 3 mpv, particularly against immune-evasive variants. Notably, the Lambda variant showed disproportionately high sensitivity to early-phase sera despite its divergence from the vaccine strain. Antibody isotyping showed that IgA and IgM decreased over time, while IgG levels were relatively more sustained. Electron microscopy revealed broader virion size heterogeneity in Lambda (50–200 nm) compared to Wuhan (80–120 nm), potentially enhancing multivalent antibody engagement. Consistently, ELISA under reduced spike density conditions showed that IgA and IgM retained stronger binding than IgG. Conclusions: These findings indicate that the decline of IgA and IgM compromises neutralization breadth, especially against structurally divergent variants such as Lambda. Sustaining dynamic multivalent isotype responses that adapt to diverse spike morphologies may be critical for broad cross-variant immunity. Full article