has the largest host range of the
complex and infects domestic animal species, wildlife, and humans. The presence of global wildlife maintenance hosts complicates bovine tuberculosis (bTB) control ...efforts and further threatens livestock and wildlife-related industries. Thus, it is imperative that early and accurate detection of
in all affected animal species is achieved. Further, an improved understanding of the complex species-specific host immune responses to
could enable the development of diagnostic tests that not only identify infected animals but distinguish between infection and active disease. The primary bTB screening standard worldwide remains the tuberculin skin test (TST) that presents several test performance and logistical limitations. Hence additional tests are used, most commonly an interferon-gamma (IFN-γ) release assay (IGRA) that, similar to the TST, measures a cell-mediated immune (CMI) response to
. There are various cytokines and chemokines, in addition to IFN-γ, involved in the CMI component of host adaptive immunity. Due to the dominance of CMI-based responses to mycobacterial infection, cytokine and chemokine biomarkers have become a focus for diagnostic tests in livestock and wildlife. Therefore, this review describes the current understanding of host immune responses to
as it pertains to the development of diagnostic tools using CMI-based biomarkers in both gene expression and protein release assays, and their limitations. Although the study of CMI biomarkers has advanced fundamental understanding of the complex host-
interplay and bTB progression, resulting in development of several promising diagnostic assays, most of this research remains limited to cattle. Considering differences in host susceptibility, transmission and immune responses, and the wide variety of
affected animal species, knowledge gaps continue to pose some of the biggest challenges to the improvement of
and bTB diagnosis.
Mycobacterium bovis is the causative agent of bovine tuberculosis (bTB) in wildlife. Confirmation of M. bovis infection relies on mycobacterial culture, which is time-consuming. Collection and ...transportation of infectious material also pose a human health risk. PrimeStore Molecular Transport Medium (MTM) has been shown to effectively inactivate infectious organisms, making it a safe method for handling infectious samples. This study investigated an in-field sampling technique for rapid, safe detection of M. bovis in buffalo tissues. Potentially infected tissues from bTB test-positive buffaloes were swabbed at post-mortem examination and stored in PrimeStore MTM at ambient temperature until Xpert MTB/RIF Ultra testing was performed. Additionally, tissue samples were frozen and transported before homogenisation for culture and Ultra testing. Oral swabs were collected from M. bovis-unexposed buffaloes as a negative control cohort. Mycobacterium tuberculosis complex (MTBC) DNA was detected by Ultra in 13/16 tissue swabs and 9/16 matched tissue homogenates from culture-confirmed M. bovis-positive buffalo tissues. MTBC DNA was not detected in swabs from M. bovis-unexposed animals, showing the potentially high specificity of Ultra with PrimeStore swabs. PrimeStore MTM sample processing, in combination with the Ultra assay, has the potential to provide a safe, rapid post-mortem screening test for M. bovis in buffaloes.
Wildlife tuberculosis is a major economic and conservation concern globally. Bovine tuberculosis (bTB), caused by
(
), is the most common form of wildlife tuberculosis. In South Africa, to date,
...infection has been detected in 24 mammalian wildlife species. The identification of
infection in wildlife species is essential to limit the spread and to control the disease in these populations, sympatric wildlife species and neighboring livestock. The detection of
-infected individuals is challenging as only severely diseased animals show clinical disease manifestations and diagnostic tools to identify infection are limited. The emergence of novel reagents and technologies to identify
infection in wildlife species are instrumental in improving the diagnosis and control of bTB. This review provides an update on the diagnostic tools to detect
infection in South African wildlife but may be a useful guide for other wildlife species.
With increasing emergence of antimicrobial resistant bacteria (ARB) and the risk this poses to public health, there are growing concerns regarding water pollution contributing to the spread of ...antimicrobial resistance (AMR) through inadequate amenities and the rapid rate of urbanization. In this study, the impact of different anthropogenic factors on the prevalence of AMR in the urban water cycle in Stellenbosch, South Africa (SA) was examined. Carbapenem, colistin, gentamicin and sulfamethoxazole resistant Gram-negative bacteria were recovered by selectively culturing aqueous, biofilm and sediment samples from sites impacted to varying degrees by informal settlements, residential, industrial, and agricultural activities, as well as a municipal wastewater treatment works (WWTW). A metagenomic approach determined community profiles and dominant AMR genes at various sites, while carbapenem resistant colonies were characterized using whole genome sequencing (WGS). Isolates recovered from agricultural sites exhibited relatively high levels of resistance to carbapenems and colistin, whereas sites impacted by domestic run-off had a higher prevalence of resistance to gentamicin and sulfamethoxazole, corresponding to usage data in SA. Similar microbial taxa were identified in raw sewage, sites downstream of informal settlements, and industrial areas that have limited waste removal infrastructure while WWTW were seen to reduce the prevalence of ARB in treated wastewater when operating efficiently. The results indicate the multiple complex drivers underpinning environmental dissemination of AMR and suggest that WWTW assist in removing AMR from the environment, reinforcing the necessity of adequate waste removal infrastructure and antibiotic stewardship measures to mitigate AMR transmission.
The results from this study are of importance as they fill a gap in the data available on environmental AMR in South Africa to date. This study was done in parallel with co-investigators focusing on the prevalence of various antimicrobials at the same sites selected in our study, verifying that the sites that are influenced by informal settlements and WWTW influent had higher concentrations of antimicrobials and antimicrobial metabolites. The various locations of the sample sites selected, the frequency of the samples collected over a year, and the different types of samples collected at each site all contribute to informing how AMR in the environment might be affected by anthropogenic activity.
The Zeitschrift für ägyptische Sprache und Altertumskunde is the oldest professional journal in Egyptology. Since 1863 it has published articles on language, literature, history, law, religion, ...science, magic, the economy, everyday experience, and the material culture of ancient Egypt as well as the history of Egyptology. The Beihefte present monographs and anthologies on the same broad spectrum of issues covered by the journal.
•Pollution alters the fungal community composition of river water.•Candida glabrata and Clavispora lusitaniae occurrence is linked with pollution.•Meyerozyma guilliermondii dominated culturable yeast ...populations in rainy seasons.•Fluconazole-resistant yeast strains were recovered from river water.•Risk of mycosis increased concurrently with pollution levels of river water.
River water is an essential human resource that may be contaminated with hazardous microorganisms. However, the risk of yeast infection through river water exposure is unclear because it is highly dependant on individual susceptibility and has therefore not been well-studied, to date. To evaluate this undefined risk, we analysed the fungal communities in less polluted (LP) and highly polluted (HP) river water, as determined using principal coordinate analysis of pollution indicators. We enumerated culturable yeasts using a thermally selective isolation procedure (37 °C) and thus promoted the growth of potentially opportunistic species. Yeast species identified as clinically relevant were then tested for antifungal resistance. In addition, we propose a quantitative microbial risk assessment (QMRA) framework to quantitatively assess the potential risk of yeast infection. Our results indicated that pollution levels significantly altered fungal communities (p = 0.007) and that genera representing opportunistic and pathogenic members were significantly more abundant in HP waters (p = 0.038). Additionally, the yeast species Candida glabrata and Clavispora lusitaniae positively correlated with other pollution indicators, demonstrating the species’ indicator potential. Our QMRA results further indicate that higher risk of infection is associated with increased water pollution levels (considering both physicochemical and bacterial indicators). Furthermore, yeast species with higher pathogenic potential present an increased risk of infection despite lower observed concentrations in the river water. Interestingly, the bloom of Meyerozyma guilliermondii during the wet season suggests that other environmental factors, such as dissolved oxygen levels and water turbulence, might affect growth characteristics of yeasts in river water, which consequently affects the distribution of annual infection risks. The presence of antifungal resistant yeasts, observed in this study, could further contribute to variation in risk distribution. Research on the ecophysiology of yeasts in these environments is therefore necessary to ameliorate the uncertainty and sensitivity of the proposed QMRA model. In addition to the vital knowledge on opportunistic and pathogenic yeast occurrence in river water and their observed association with pollution, this study provides valuable methods and insights to initiate future QMRAs of yeast infections.
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Abstract
Background
Microwave imaging has been proposed for medical applications, creating maps related to water content of tissues. Breast imaging has emerged as a key application because the ...signals can be coupled directly into the breast and experience limited attenuation in fatty tissues. While the literature contains reports of tumor detection with microwave approaches, there is limited exploration of treatment monitoring.
Purpose
This study aims to detect treatment‐related changes in breast tissue with a low‐resolution microwave scanner.
Methods
Microwave scans of 15 patients undergoing treatment for early‐stage breast cancer are collected at up to 4 time points: after surgery (baseline), 6 weeks after accelerated partial breast radiation, as well as 1 and 2 years post‐treatment. Both the treated and untreated breast are scanned at each time point. The microwave scanner consists of planar transmit and receive arrays and uses signals from 0.1 to 10 GHz. The average microwave frequency properties (permittivity) are calculated for each scan to enable quantitative comparison. Baseline and 6‐week results are analyzed with a two‐way ANOVA with blocking.
Results
Consistent properties are observed for the untreated breast over time, similar to a previous study. Comparison of the scans of the treated and untreated breast suggests increased properties related to treatment, particularly at baseline and 6‐weeks following radiotherapy. Analysis of the average properties of the scans with ANOVA indicates statistically significant differences () in the treated and untreated breast at these time points.
Conclusions
Microwave imaging has the potential to track treatment‐related changes in breast tissues.
Over 27 million individuals are affected every year worldwide with central nervous system (CNS) injuries. These injuries include but are not limited to traumatic brain injury (TBI) and spinal cord ...injury (SCI). CNS injuries remain a significant public health concern which demands reliable tools for rapid, on-sight, on-field, and point-of-care diagnostic (POC) solutions. To address these challenges, we developed a low-cost, open-source, hand-held, portable, and POC detection technology, termed as MicroDrop (μDrop), which can simultaneously detect up to eight target biomolecules and display results in both analog and digital formats. The data acquired is stored wirelessly in a cloud server for further investigation and statistical analysis. Multiplexing capability of μDrop and immuno-biosensors detects and quantifies Cleaved-Tau Protein (C-Tau) and Neuron-Filament (NFL) proteins in the blood of TBI patients. Immuno-biosensors rapidly sense the two target proteins in less than 30 min, with μDrop and a conventional potentiostat. C-Tau and NFL were selectively detected with μDrop within the dynamic range of 10 pg/mL - 100 ng/mL and the sensitivity range of 47 μA/pg mm2 - 65 μA/pg mm2. Comparing the biosensing performance with enzyme-linked immunosorbent assays (ELISA) shows that the immuno-biosensors combined with μDrop could successfully differentiate between clinical controls and injured patients.
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•The development of opensource multi-analyte portable electrochemical sensing device (μDrop).•μDrop performs differential pulse voltammetry mode of electrochemical sensing.•The comparable performance of μDrop to a commercial potentiostat.•Accurate detection of cleaved tau (C-Tau) and neuron filament light (NFL) in the blood of TBI patients.
The African buffalo (Syncerus caffer) is an economically and ecologically important wildlife species in South Africa; it is also a primary wildlife maintenance host of Mycobacterium bovis. Accurate ...and early detection of M. bovis infection in buffaloes is important for controlling transmission. Assays that detect cell-mediated immune responses to M. bovis in buffaloes have been developed although these often display suboptimal sensitivity or specificity. Therefore, the aim of this study was to evaluate the newly available Mabtech bovine interferon-gamma (IFN-γ) ELISAPRO kit and optimize its use for detection of buffalo IFN-γ in whole blood samples stimulated with the QuantiFERON® TB Gold Plus antigens. Additionally, the test performance of the Mabtech IFN-γ release assay (IGRA) was compared to the currently used Cattletype® IGRA by determining buffalo-specific cut-off values for the two IGRAs and using gold standard-positive (M. bovis culture-confirmed) and M. bovis-unexposed negative cohorts. Validation of the Mabtech ELISA revealed negligible matrix interference and a linear and parallel response for recombinant bovine and native buffalo IFN-γ in the range 1.95–250 pg/mL. Intra- and inter-assay reproducibility produced coefficients of variation <5.5 % and <6.1 %, respectively, with a limit of detection at 3.2 pg/mL. Using receiver operator characteristic curve analyses, buffalo-specific cut-off values were calculated as 8 pg/mL for the Mabtech IGRA and 5 % (signal to positive control ratio) for the Cattletype® IGRA. The sensitivities were 89 % and 83 % for the Mabtech and Cattletype IGRAs with specificities of 94 % and 97 %, respectively. Although the species-specific cut-off values require further evaluation in a relevant test group, the results suggest that the Mabtech IGRA is a promising, sensitive and specific diagnostic tool for M. bovis detection in African buffaloes.
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