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1.
Lancet Microbe ; : 100911, 2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39278232

ABSTRACT

BACKGROUND: The global distribution and prevalence of arboviral diseases have increased in recent years, driven by factors such as climate change, biodiversity loss, globalisation, and urbanisation. These diseases are often underestimated due to uneven surveillance and unreported asymptomatic cases. Current surveillance relies on vector and clinical surveillance. In this study, we aimed to explore wastewater-based surveillance (WBS) as an additional tool for dengue virus (DENV) and chikungunya virus (CHIKV) tracking. METHODS: In this exploratory surveillance study, WBS was done at eleven wastewater treatment plants in three regions in Portugal (North, Lisboa and Vale do Tejo, and south). Using quantitative RT-PCR, we quantified in raw wastewater the RNA concentrations of DENV and CHIKV (non-structural viral protein 1 [nsP1] and envelope protein [E1] genes) once every 2 weeks for a period of 11 months, between May 16, 2022, and April 19, 2023. Results were normalised with crAssphage (concentration of target viral RNA divided by the concentration of crAssphage DNA) and provided as median normalised viral load. Prevalence (proportion of positive samples) and viral quantities were summarised for the total sampling period, by calendar month, and by seasons. FINDINGS: 273 samples were collected from 11 wastewater treatment plants situated across the North (n=75 samples), Lisboa and Vale do Tejo (n=98), and south (n=100) regions of Portugal. DENV was detected in 68 (25%) of 273 samples, with a median viral load of 1·1 × 10-4 (IQR 3·2 × 10-5 to 8·0 × 10-4). CHIKV was detected in 30 (11%) of 273 samples, with median viral loads of 3·1 × 10-4 (1·6 × 10-4 to 6·4 × 10-4; nsP1 gene) and 7·8 × 10-4 (4·2 × 10-4 to 2·0 × 10-³; E1 gene). The pattern of occurrence of CHIKV was similar between regions whereas slight differences were found for DENV. When combining results for the three studied regions, DENV prevalence and viral load had two seasonal peaks (summer and winter) and CHIKV prevalence and viral load had a single peak during March and April of 2023. INTERPRETATION: This study highlights the potential of WBS as a potent tool for gauging the epidemiological landscape of DENV and CHIKV in Portugal, where autochthonous cases have not yet been detected. WBS could serve as an additional element to conventional surveillance approaches, especially in areas where real-time clinical surveillance data are scarce or delayed. FUNDING: EU Emergency Support Instrument and Fundação para a Ciencia e Tecnologia.

2.
Sci Total Environ ; 953: 176053, 2024 Nov 25.
Article in English | MEDLINE | ID: mdl-39244050

ABSTRACT

In many Mediterranean ecosystems, animal tuberculosis (TB), caused by Mycobacterium bovis, an ecovar of Mycobacterium tuberculosis complex (MTBC), is maintained by multi-host communities. It is hypothesised that interspecies transmission is mainly indirect via shared contaminated environments. Therefore, identifying spatial areas where MTBC bacteria occur and quantifying space use by susceptible hosts might help predict the spatial likelihood of transmission across the landscape. Here, we aimed to evaluate the transmission risk of MTBC in a multi-host system involving wildlife (ungulates and carnivores) and cattle (Bos taurus). We collected eighty-nine samples from natural substrates (water, soil, and mud) at 38 sampling sites in a TB endemic area within a Mediterranean agroforestry system in Portugal. These samples were analysed by real-time PCR to detect MTBC DNA. Additionally, host-specific space use intensity maps were obtained through camera-trapping covering the same sampling sites. Results evidenced that a significant proportion of samples were positive for MTBC DNA (49 %), suggesting that the contamination is widespread in the area. Moreover, they showed that the probability of MTBC occurrence in the environment was significantly influenced by topographic features (i.e., slope), although other non-significant predictor related with soil conditions (SMI: soil moisture index) incorporated the MTBC contamination model. The integration of host space use intensity maps with the spatial detection of MTBC showed that the red deer (Cervus elaphus) and wild boar (Sus scrofa) exhibited the highest percentages of high-risk areas for MTBC transmission. Furthermore, when considering the co-occurrence of multiple hosts, transmission risk analyses revealed that 26.5 % of the study area represented high-risk conditions for MTBC transmission, mainly in forest areas.


Subject(s)
Mycobacterium bovis , Animals , Portugal , Cattle , Tuberculosis/transmission , Tuberculosis/epidemiology , Mycobacterium tuberculosis , Environmental Monitoring/methods , Animals, Wild/microbiology
3.
STAR Protoc ; 5(3): 103302, 2024 Sep 20.
Article in English | MEDLINE | ID: mdl-39264805

ABSTRACT

Helicobacter-induced gastric cancer progresses very slowly, even in animal models, making it difficult to study. Here, we present a protocol to establish an accelerated murine model for Helicobacter-induced gastric cancer. We describe steps for infecting mice with Helicobacter felis, harvesting gastric tissue, assessing disease severity by histopathologic scoring, and performing gene expression studies with RT-qPCR and RNA sequencing. The accelerated model shows rapid progression of the disease, with gastric precancerous lesions developing within 6 months post-infection with Helicobacter. For complete details on the use and execution of this protocol, please refer to Bali et al.1.


Subject(s)
Disease Models, Animal , Helicobacter Infections , Stomach Neoplasms , Animals , Stomach Neoplasms/microbiology , Stomach Neoplasms/pathology , Mice , Helicobacter Infections/microbiology , Helicobacter Infections/pathology , Helicobacter felis , Female
5.
Microbes Infect ; : 105405, 2024 Aug 22.
Article in English | MEDLINE | ID: mdl-39173900

ABSTRACT

Mycobacterium caprae is linked to regular outbreaks of tuberculosis (TB) in geographically distinct caprine populations across Europe, namely Iberia where this ecovar may represent up to 8% of total animal TB cases, circulating in multi-host communities encompassing domestic ruminants and wildlife, representing severe financial losses. It also causes zoonotic human disease. In this work, we undertake the first phylodynamic and phylogeographic analyses of M. caprae to reconstruct past demography and transmission chains. First, we examined the worldwide diversity of M. caprae based on 229 unpublished and publicly available whole genome sequences, depicting Asian, Central-East European, and Iberian clades. Phylodynamic analyses of the SB0157 Iberian clade (n = 81) positioned the most recent common ancestor in goats, around 100 years ago. Host transition events were common between goats, wild boars, and humans, possibly resulting from mixed farming, extensive management, and close human proximity, facilitating interspecific transmission. We show the spread of M. caprae on multiple scales due to local and transnational animal trade, supporting historical and sustained cross-species transmission in Iberia. We highlight the value of intersecting genomic epidemiology with molecular ecology to resolve epidemiological links and show that an EU-official eradication program in goats is utterly needed to control TB in a multi-host scenario.

6.
Am J Clin Nutr ; 120(3): 656-663, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38971470

ABSTRACT

BACKGROUND: Costa Rica is experiencing a fast demographic aging. Healthy diets may help to ameliorate the burden of aging-related conditions. OBJECTIVE: This study aimed to investigate the association of a traditional dietary pattern and 2 of its major components (beans and rice) with all-cause mortality among elderly Costa Ricans. METHODS: The Costa Rican Longevity and Healthy Aging Study (CRELES), a prospective cohort study of 2827 elderly Costa Ricans (60+ y at baseline), started in 2004. We used a food frequency questionnaire (FFQ) to assess usual diet. We calculated dietary patterns using principal component analysis. Multivariate energy-adjusted proportional-hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: Over a 15-y follow-up, encompassing 24,304 person-years, 1667 deaths occurred. The traditional Costa Rican dietary pattern was more frequent in rural parts of the country, and it was inversely associated with all-cause mortality. Subjects in the fifth quintile of intake had 18% lower all-cause mortality than those in the first quintile (HR: 0.82; 95% CI: 0.69, 0.98; P-trend = 0.01), particularly among males (HR: 0.73; 95% CI: 0.56, 0.95). Bean intake was associated with lower all-cause mortality among all subjects (HR: 0.79; 95% CI: 0.68, 0.91, highest compared with lowest tertile) and in sex-stratified analysis. Rice consumption was inversely associated with all-cause mortality solely among males (HR: 0.75; 95% CI: 0.60, 0.94, highest compared with lowest tertile). CONCLUSIONS: Our results suggest that a traditional Costa Rican rural dietary pattern is associated with lower all-cause mortality in elderly Costa Ricans. Beans, a major component of this traditional dietary pattern, was also associated with lower all-cause mortality. These findings could have important implications for public health, given the nutritional transition and the reduction of intake of traditional diets in Latin American countries.


Subject(s)
Diet , Longevity , Rural Population , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Central American People , Cohort Studies , Costa Rica/epidemiology , Healthy Aging , Mortality , Oryza , Prospective Studies , Rural Population/statistics & numerical data
7.
iScience ; 27(7): 110244, 2024 Jul 19.
Article in English | MEDLINE | ID: mdl-39040070

ABSTRACT

Prior research has suggested that GATA6+ pericardial macrophages may traffic to the myocardium to prevent interstitial fibrosis after myocardial infarction (MI), while subsequent literature claims that they do not. We demonstrate that GATA6+ pericardial macrophages are critical for preventing IL-33 induced pericarditis and attenuate trafficking of inflammatory monocytes and granulocytes to the pericardial cavity after MI. However, absence of GATA6+ macrophages did not affect myocardial inflammation due to MI or coxsackievirus-B3 induced myocarditis, or late-stage cardiac fibrosis and cardiac function post MI. GATA6+ macrophages are significantly less transcriptionally active following stimulation in vitro compared to bone marrow-derived macrophages and do not induce upregulation of inflammatory markers in fibroblasts. This suggests that GATA6+ pericardial macrophages attenuate inflammation through their interactions with surrounding cells. We therefore conclude that GATA6+ pericardial macrophages are critical in modulating pericardial inflammation, but do not play a significant role in controlling myocardial inflammation or fibrosis.

8.
Nat Commun ; 15(1): 6411, 2024 Jul 30.
Article in English | MEDLINE | ID: mdl-39080340

ABSTRACT

Proteins in the open ocean represent a significant source of organic matter, and their profiles reflect the metabolic activities of marine microorganisms. Here, by analyzing metaproteomic samples collected from the Pacific, Atlantic and Southern Ocean, we reveal size-fractionated patterns of the structure and function of the marine microbiota protein pool in the water column, particularly in the dark ocean (>200 m). Zooplankton proteins contributed three times more than algal proteins to the deep-sea community metaproteome. Gammaproteobacteria exhibited high metabolic activity in the deep-sea, contributing up to 30% of bacterial proteins. Close virus-host interactions of this taxon might explain the dominance of gammaproteobacterial proteins in the dissolved fraction. A high urease expression in nitrifiers suggested links between their dark carbon fixation and zooplankton urea production. In summary, our results uncover the taxonomic contribution of the microbiota to the oceanic protein pool, revealing protein fluxes from particles to the dissolved organic matter pool.


Subject(s)
Bacterial Proteins , Gammaproteobacteria , Microbiota , Oceans and Seas , Proteomics , Seawater , Zooplankton , Proteomics/methods , Zooplankton/metabolism , Seawater/microbiology , Seawater/chemistry , Bacterial Proteins/metabolism , Bacterial Proteins/genetics , Gammaproteobacteria/metabolism , Gammaproteobacteria/genetics , Animals , Proteome/metabolism , Food Chain , Carbon Cycle
9.
Environ Pollut ; 356: 124241, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-38825220

ABSTRACT

Staphylococcus aureus thrives at animal-human-environment interfaces. A large-scale work from our group indicated that antimicrobial resistance (AMR) in commensal S. aureus strains from wild ungulates is associated with agricultural land cover and livestock farming, raising the hypothesis that AMR genes in wildlife strains may originate from different hosts, namely via exchange of mobile genetic elements (MGE). In this work, we generate the largest available dataset of S. aureus draft genomes from wild ungulates in Portugal and explore their mobilome, which can determine important traits such as AMR, virulence, and host specificity, to understand MGE exchange. Core genome multi-locus sequence typing based on 98 newly generated draft genomes and 101 publicly available genomes from Portugal demonstrated that the genomic relatedness of S. aureus from wild ungulates assigned to livestock-associated sequence types (ST) is greater compared to wild ungulate isolates assigned to human-associated STs. Screening of host specificity determinants disclosed the unexpected presence in wildlife of the immune evasion cluster encoded in φSa3 prophage, described as a human-specific virulence determinant. Additionally, two plasmids, pAVX and pETB, previously associated with avian species and humans, respectively, and the Tn553 transposon were detected. Both pETB and Tn553 encode penicillin resistance through blaZ. Pangenome analysis of wild ungulate isolates shows a core genome fraction of 2133 genes, with isolates assigned to ST72 and ST3224 being distinguished from the remaining by MGEs, although there is no reported role of these in adaptation to wildlife. AMR related gene clusters found in the shell genome are directly linked to resistance against penicillin, macrolides, fosfomycin, and aminoglycosides, and they represent mobile ARGs. Altogether, our findings support epidemiological interactions of human and non-human hosts at interfaces, with MGE exchange, including AMR determinants, associated with putative indirect movements of S. aureus among human and wildlife hosts that might be bridged by livestock.


Subject(s)
Animals, Wild , Staphylococcal Infections , Staphylococcus aureus , Animals , Staphylococcus aureus/genetics , Humans , Portugal , Animals, Wild/microbiology , Staphylococcal Infections/veterinary , Staphylococcal Infections/microbiology , Staphylococcal Infections/epidemiology , Interspersed Repetitive Sequences/genetics , Genome, Bacterial , Livestock/microbiology , Virulence/genetics , Multilocus Sequence Typing , Deer , Host Specificity
10.
Sci Total Environ ; 944: 173875, 2024 Sep 20.
Article in English | MEDLINE | ID: mdl-38866158

ABSTRACT

West Nile (WNV) is a zoonotic arbovirus with an expanding geographical range and epidemic activity in Europe. Not having yet experienced a human-associated epidemic, Portugal remains an outlier in the Mediterranean basin. In this study, we apply ecological niche modelling informed by WNV historical evidence and a multitude of environmental variables from across Portugal. We identify that ecological backgrounds compatible with WNV historical circulation are mostly restricted to the south, characterized by a warmer and drier climate, high avian diversity, specific avian species and land types. We estimate WNV ecological suitability across the country, identifying overlaps with the distributions of the three relevant hosts (humans, birds, equines) for public and animal health. From this, we propose a category-based spatial framework providing first of a kind valuable insights for WNV surveillance in Portugal under the One Health nexus. We forecast that near future climate trends alone will contribute to pushing adequate WNV ecological suitability northwards, towards regions with higher human density. This unique perspective on the past, present and future ecology of WNV addresses existing national knowledge gaps, enhances our understanding of the evolving emergence of WNV, and offers opportunities to prepare and respond to the first human-associated epidemic in Portugal.


Subject(s)
Birds , One Health , West Nile Fever , West Nile virus , Portugal/epidemiology , West Nile Fever/epidemiology , Animals , Humans , Ecosystem , Horses
11.
An Acad Bras Cienc ; 96(3): e20230811, 2024.
Article in English | MEDLINE | ID: mdl-38865509

ABSTRACT

Cancer is a complex and multifactorial disease characterized by uncontrolled cell growth and is one of the main causes of death in the world. This work aimed to evaluate a small series of 10 different indole-thiosemicarbazone compounds as potential antitumor agents. This is a pioneering study. For this, the antioxidant and cytotoxic capacity against normal and tumor cells was evaluated. The results showed that the compounds were able to promote moderate to low antioxidant activity for the ABTS radical scavenging assay. ADMET in silico assays showed that the compounds exhibited good oral bioavailability. As for toxicity, they were able to promote low cytotoxicity against normal cells, in addition to not being hemolytic. The compounds showed promising in vitro antitumor activity against the T47D, MCF-7, Jurkat and DU-145 strains, not being able to inhibit the growth of the Hepg2 strain. Through this in vitro study, it can be concluded that the compounds are potential candidates for antitumor agents.


Subject(s)
Antineoplastic Agents , Antioxidants , Indoles , Thiosemicarbazones , Humans , Thiosemicarbazones/pharmacology , Thiosemicarbazones/chemistry , Thiosemicarbazones/pharmacokinetics , Indoles/pharmacology , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Antioxidants/pharmacology , Cell Line, Tumor , Computer Simulation , Drug Screening Assays, Antitumor , Cell Proliferation/drug effects
12.
Sci Total Environ ; 946: 174272, 2024 Oct 10.
Article in English | MEDLINE | ID: mdl-38925382

ABSTRACT

In response to the rapid emergence and dissemination of antimicrobial resistant bacteria (ARB) and genes (ARGs), integrated surveillance systems are needed to address antimicrobial resistance (AMR) within the One Health Era. Wastewater analyses enable biomarker monitoring at the sewershed level, offering timely insights into pathogen circulation and ARB/ARGs trends originating from different compartments. During two consecutive epidemic waves of the COVID-19 pandemic in Portugal, taxonomic and functional composition of raw urban wastewater from two wastewater treatment plants (WWTPs) representing one million in equivalent population, located in the main urban areas of the country, were profiled by shotgun metagenomics. Hospital wastewater from two central hospitals located in the WWTPs catchment areas were also sequenced. The resistome and virulome were profiled using metagenomic assemblies without taxonomic constraint, and then specifically characterized for ESKAPE pathogens. Urban and hospital wastewater exhibited specific microbiota signatures, Pseudomonadota dominated in the first and Bacteroidota in the latter. Correlation network analyses highlighted 85 (out of top 100) genera co-occurring across samples. The most frequent ARGs were classified in the multidrug, tetracyclines, and Macrolides, Lincosamides, Streptogramins (MLS) classes. Links established between AMR determinants and bacterial hosts evidenced that the diversity and abundance of ARGs is not restricted to ESKAPE, being also highly predominant among emergent enteropathogens, like Aeromonas and Aliarcobacter, or in the iron (II) oxidizer Acidovorax. The Aliarcobacter genus accumulated high abundance of sulphonamides and polymyxins ARGs, while Acinetobacter and Aeromonas hosted the highest abundance of ARGs against beta-lactams. Other bacteria (e.g. Clostridioides, Francisella, Vibrio cholerae) and genes (e.g. vanA-type vancomycin resistance) of public health interest were detected, with targeted monitoring efforts being needed to establish informative baseline data. Altogether, results highlight that wastewater monitoring is a valuable component of pathogen and AMR surveillance in healthy populations, providing a community-representative snapshot of public health trends beyond priority pathogens.


Subject(s)
Microbiota , Wastewater , Wastewater/microbiology , Portugal , Microbiota/drug effects , Microbiota/genetics , Metagenomics , Public Health , Bacteria/genetics , Bacteria/drug effects , Environmental Monitoring , Drug Resistance, Bacterial/genetics , COVID-19 , Waste Disposal, Fluid
13.
Microorganisms ; 12(6)2024 May 25.
Article in English | MEDLINE | ID: mdl-38930449

ABSTRACT

Environmental decontamination and water disinfection practices are hallmarks of disease prevention and control in agricultural and public health settings. Informed fit-to-purpose biocontainment is thus dependent on methodologies accurately assessing microbial burden and viability. Also, rigorous evaluation of the efficacy of biocontrol measures implies monitoring microbial inactivation after decontamination/disinfection procedures. In this study, we used flow cytometry coupled with a resuscitation protocol to monitor the metabolic inactivation of bacteria capable of entering non-cultivable states, after the application of a chlorine-based water disinfectant. For this purpose, we used Mycobacterium bovis BCG as a model of slow-growing bacteria able to enter dormancy and representing a multi-host pathogen in a zoonotic disease system-animal tuberculosis-thriving both across temperate and semi-arid regions and involving environmental contamination. The biocide activity of a commercial sodium dichloroisocyanurate (NaDCC) disinfectant against M. bovis BCG was evaluated through mock environmental matrix tests. Using the manufacturer-recommended dosage of NaDCC, BCG cells were apparently inactivated after 24 h upon exposure. However, we show via flow cytometry that, upon exposure to optimal growth conditions, mycobacterial cells were able to regain metabolic activity shortly after, highlighting a sublethal effect of NaDCC at the recommended commercial dosage due to reversible BCG cell damage. In contrast, increasing twice the disinfectant dosage completely inactivated BCG cells after 24 h of exposure, with full irreversible loss of metabolic activity. Methodological workflows based on conventional culture or PCR would have missed the detection of these dormant subpopulations that were in fact able to resume growth when following the recommendations of a commercial disinfectant. This study highlights the superior, high-resolution value of single-cell approaches, such as flow cytometry, to accurately assess the activity of biocides against metabolically heterogeneous and dormant pathogenic bacteria with environmental cycles, supporting data-driven prioritization of environmental management and disinfection options in contaminated vulnerable settings.

14.
Schizophr Res ; 269: 71-78, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38749320

ABSTRACT

One-third of people with schizophrenia have elevated levels of anti-gliadin antibodies (AGA IgG). A 5-week randomized double-blind pilot study was performed in 2014-2017 in an inpatient setting to test the effect of a gluten-free diet (GFD) on participants with schizophrenia or schizoaffective disorder who also had elevated AGA IgG (≥ 20 U) but were negative for celiac disease. This earlier pilot study reported that the GFD-group showed improved gastrointestinal and psychiatric symptoms, and also improvements in TNF-α and the inflammatory cytokine IL-23. Here, we performed measurements of these banked plasma samples to detect levels of oxidative stress (OxSt) using a recently developed iridium (Ir)-reducing capacity assay. Triplicate measurements of these samples showed an Intraclass Correlation Coefficient of 0.84 which indicates good reproducibility. Further, a comparison of the OxSt measurements at the baseline and 5-week end-point for this small sample size shows that the GFD-group (N = 7) had lowered OxSt levels compared to the gluten-containing diet group (GCD; N = 9; p = 0.05). Finally, we showed that improvements in OxSt over these 5 weeks were correlated to improvements in gastrointestinal (r = +0.64, p = 0.0073) and psychiatric (r = +0.52, p = 0.039) symptoms. Also, we showed a possible association between the decrease in OxSt and the lowered levels of IL-23 (r = +0.44, p = 0.087), although without statistical significance. Thus, the Ir-reducing capacity assay provides a simple, objective measure of OxSt with the results providing further evidence that inflammation, redox dysregulation and OxSt may mediate interactions between the gut and brain.


Subject(s)
Diet, Gluten-Free , Oxidative Stress , Schizophrenia , Humans , Schizophrenia/diet therapy , Schizophrenia/blood , Pilot Projects , Oxidative Stress/physiology , Male , Adult , Female , Middle Aged , Double-Blind Method , Psychotic Disorders/diet therapy , Psychotic Disorders/blood , Psychotic Disorders/immunology , Gliadin/immunology
15.
Sci Adv ; 10(20): eadn5143, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38748788

ABSTRACT

Marine heterotrophic prokaryotes primarily take up ambient substrates using transporters. The patterns of transporters targeting particular substrates shape the ecological role of heterotrophic prokaryotes in marine organic matter cycles. Here, we report a size-fractionated pattern in the expression of prokaryotic transporters throughout the oceanic water column due to taxonomic variations, revealed by a multi-"omics" approach targeting ATP-binding cassette (ABC) transporters and TonB-dependent transporters (TBDTs). Substrate specificity analyses showed that marine SAR11, Rhodobacterales, and Oceanospirillales use ABC transporters to take up organic nitrogenous compounds in the free-living fraction, while Alteromonadales, Bacteroidetes, and Sphingomonadales use TBDTs for carbon-rich organic matter and metal chelates on particles. The expression of transporter proteins also supports distinct lifestyles of deep-sea prokaryotes. Our results suggest that transporter divergency in organic matter assimilation reflects a pronounced niche separation in the prokaryote-mediated organic matter cycles.


Subject(s)
Microbiota , Seawater/microbiology , Prokaryotic Cells/metabolism , ATP-Binding Cassette Transporters/metabolism , Substrate Specificity , Phylogeny , Bacteria/metabolism , Bacteria/classification , Aquatic Organisms/metabolism , Membrane Transport Proteins/metabolism , Carbon/metabolism
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124378, 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-38701577

ABSTRACT

Absorption spectra of aqueous samples measured by transmission need to be acquired using very thin cells (5-50 µm) when targeting the mid-infrared (mid-IR) region due to the strong background absorbance of liquid water. The thickness of the cell used controls the pathlength of the light through the sample, a value needed to transform absorption spectra into molar absorption coefficient spectra, or to determine solute concentrations from absorption spectra. The most accurate way to determine the thickness of an empty cell (i.e., filled with air) is from the period of an interference pattern, known as interference fringes, that arises when the cell is placed perpendicular to the path of light in the spectrometer. However, this same approach is not directly applicable to determine the thickness of a cell filled with an aqueous solution, due partially to the smaller amplitude of the interference fringes but fundamentally caused by its complex waveform, with a wavenumber-dependent oscillation period. Here, using Fresnel equations, we derived analytical expressions to model interference fringes in absorption spectra obtained by transmission, which are also valid for aqueous samples. We also present a novel Fourier-based analysis of the interference fringes that, in combination with the derived analytical expressions, allowed us to determine the pathlength of aqueous samples with an error below âˆ¼ 50 nm. We implemented this novel approach to analyze interference fringes as a Live Script running in the software Matlab. As an application, we measured the absorption spectra of a 97 mM solution of MES buffer at pH 3.4 and pH 8.4 using cells of various nominal thicknesses (6, 25 and 50 µm), whose actual thicknesses were determined using the present approach. The derived molar absorption coefficient spectrum for both the acidic and basic forms of MES were virtually identical regardless of the cell, indicating that the determined thicknesses were likely very accurate. These results illustrate the utility of the present methodology in obtaining accurate molar absorption coefficient spectra of water-soluble molecules in the mid-IR region.

17.
Microbiol Spectr ; 12(7): e0382923, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38771094

ABSTRACT

Mycobacterium bovis causes animal tuberculosis in livestock and wildlife, with an impact on animal health and production, wildlife management, and public health. In this work, we sampled a multi-host tuberculosis community from the official hotspot risk area of Portugal over 16 years, generating the largest available data set in the country. Using phylogenetic and ecological modeling, we aimed to reconstruct the history of circulating lineages across the livestock-wildlife interface to inform intervention and the implementation of genomic surveillance within the official eradication plan. We find evidence for the co-circulation of M. bovis European 1 (Eu1), Eu2, and Eu3 clonal complexes, with Eu3 providing sufficient temporal signal for further phylogenetic investigation. The Eu3 most recent common ancestor (bovine) was dated in the 1990s, subsequently transitioning to wildlife (red deer and wild boar). Isolate clustering based on sample metadata was used to inform phylogenetic inference, unravelng frequent transmission between two clusters that represent an ecological corridor of previously unrecognized importance in Portugal. The latter was associated with transmission at the livestock-wildlife interface toward locations with higher temperature and precipitation, lower agriculture and road density, and lower host densities. This is the first analysis of M. bovis Eu3 complex in Iberia, shedding light on background ecological factors underlying long-term transmission and informing where efforts could be focused within the larger hotspot risk area of Portugal. IMPORTANCE: Efforts to strengthen surveillance and control of animal tuberculosis (TB) are ongoing worlwide. Here, we developed an eco-phylodynamic framework based on discrete phylogenetic approaches informed by M. bovis whole-genome sequence data representing a multi-host transmission system at the livestock-wildlife interface, within a rich ecological landscape in Portugal, to understand transmission processes and translate this knowledge into disease management benefits. We find evidence for the co-circulation of several M. bovis clades, with frequent transmission of the Eu3 lineage among cattle and wildlife populations. Most transition events between different ecological settings took place toward host, climate and land use gradients, underscoring animal TB expansion and a potential corridor of unrecognized importance for M. bovis maintenance. Results stress that animal TB is an established wildlife disease without ecological barriers, showing that control measures in place are insufficient to prevent long-distance transmission and spillover across multi-host communities, demanding new interventions targeting livestock-wildlife interactions.


Subject(s)
Animals, Wild , Mycobacterium bovis , Phylogeny , Portugal/epidemiology , Animals , Mycobacterium bovis/genetics , Mycobacterium bovis/classification , Mycobacterium bovis/isolation & purification , Cattle , Animals, Wild/microbiology , Livestock/microbiology , Tuberculosis, Bovine/transmission , Tuberculosis, Bovine/microbiology , Tuberculosis, Bovine/epidemiology , Deer/microbiology , Sus scrofa/microbiology , Tuberculosis/transmission , Tuberculosis/microbiology , Tuberculosis/epidemiology , Tuberculosis/veterinary
18.
J Hazard Mater ; 472: 134473, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38703681

ABSTRACT

Spreading of Mycobacterium bovis causing animal tuberculosis (TB) at livestock-wildlife-environment interfaces remains a significant problem. Recently, we provided evidence of widespread environmental contamination of an endemic animal TB setting with viable and dormant M. bovis cells able to recover metabolic activity, making indirect transmission via environmental contamination plausible. We now report the first whole genome sequences of M. bovis recovered from the environment. We establish epidemiological links at the environment-animal interface by phylogenomic comparison of these M. bovis genomes with those isolated from livestock and wild ungulates from the same area. Environmental and animal genomes are highly intertwined and distribute similarly into the same M. bovis lineages, supporting several instances of environmental contamination. This study provides compelling evidence of M. bovis excretion into the environment and viability maintenance, supporting the environment as a potential source of new infection. These insights have clear implications for policy formulation, advocating environmental surveillance and an ecosystem perspective in TB control programs. ENVIRONMENTAL IMPLICATION: We report the first whole genome sequences of M. bovis from the environment and establish epidemiological links at the environment-animal interface, demonstrating close phylogenomic relatedness of animal and environmental M. bovis. Definitive evidence of M. bovis excretion into the environment with viability maintenance is provided, supporting the environment as a potential source of new infection. Implications of this work include methodological innovations offering a tool to resolve indirect transmission chains and support customized biosecurity measures. Policy formulation aiming at the control of animal tuberculosis and cost mitigation should consider these findings, encouraging environmental surveillance in official eradication programmes.


Subject(s)
Mycobacterium bovis , Phylogeny , Whole Genome Sequencing , Mycobacterium bovis/genetics , Animals , Genome, Bacterial , Tuberculosis, Bovine/transmission , Tuberculosis, Bovine/microbiology , Tuberculosis/transmission , Tuberculosis/microbiology , Cattle , Environmental Microbiology , Animals, Wild/microbiology
19.
Sci Total Environ ; 933: 173027, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38729368

ABSTRACT

Staphylococcus aureus is a versatile pathobiont, exhibiting a broad host range, including humans, other mammals, and avian species. Host specificity determinants, virulence, and antimicrobial resistance genes are often shared by strains circulating at the animal-human interface. While transmission dynamics studies have shown strain exchange between humans and livestock, knowledge of the source, genetic diversification, and transmission drivers of S. aureus in wildlife lag behind. In this work, we explore a wide array of S. aureus genomes from different sources in the Iberian Peninsula to understand population structure, gene content and niche adaptation at the human-livestock-wildlife nexus. Through Bayesian inference, we address the hypothesis that S. aureus strains in wildlife originate from humanized landscapes, either from contact with humans or through interactions with livestock. Phylogenetic reconstruction applied to whole genome sequence data was completed with a dataset of 450 isolates featuring multiple clones from the 1990-2022 period and a subset of CC398 strains representing the 2008-2022 period. Phylodynamic signatures of S. aureus from the Iberian Peninsula suggest widespread circulation of most clones among humans before jumping to other hosts. The number of transitions of CC398 strains within each host category (human, livestock, wildlife) was high (88.26 %), while the posterior probability of transitions from livestock to wildlife was remarkably high (0.99). Microbial genome-wide association analysis did not evidence genome rearrangements nor biomarkers suggesting S. aureus niche adaptation to wildlife, thus supporting recent spill overs. Altogether, our findings indicate that S. aureus isolates collected in the past years from wildlife most likely represent multiple introduction events from livestock. The clonal origin of CC398 and its potential to disseminate and evolve through different animal host species are highlighted, calling for management practices at the livestock-wildlife axis to improve biosecurity and thus restrict S. aureus transmission and niche expansion along gradients of human influence.


Subject(s)
Animals, Wild , Livestock , Staphylococcal Infections , Staphylococcus aureus , Animals , Livestock/microbiology , Staphylococcus aureus/genetics , Staphylococcal Infections/veterinary , Staphylococcal Infections/epidemiology , Staphylococcal Infections/microbiology , Animals, Wild/microbiology , Spain , Humans , Phylogeny , Portugal/epidemiology
20.
Open Forum Infect Dis ; 11(4): ofae128, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38560605

ABSTRACT

Nontuberculous mycobacteria (NTM) can cause a variety of infections, including serious pulmonary disease. Treatment encompasses polypharmacy, with a targeted regimen of 2-5 active medications, depending on site of infection, species, and clinical characteristics. Medications may include oral, intravenous, and inhalational routes. Medication acquisition can be challenging for numerous reasons, including investigational status, limited distribution models, and insurance prior authorization. Additionally, monitoring and managing adverse reactions and drug interactions is a unique skill set. While NTM is primarily medically managed, clinicians may not be familiar with the intricacies of medication selection, procurement, and monitoring. This review offers insights into the pharmacotherapeutic considerations of this highly complex disease state, including regimen design, medication acquisition, safety monitoring, relevant drug-drug interactions, and adverse drug reactions.

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