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Background: Canine superficial pyoderma is a common bacterial skin infection of dogs, generally caused by Staphylococcus pseudintermedius. The C4 strain of Staphylococcus felis was recently discovered to have strong antimicrobial activity against S. pseudintermedius in mice., Objectives: We aimed to evaluate in vitro if this antimicrobial activity was maintained using a novel canine skin explant model., Materials and Methods: Punch biopsies (8 mm) of skin from recently euthanised dogs were collected and placed into six-well plates on top of an agarose pedestal., Results: Histological examination of the skin explants showed an intact dermal-epidermal organisation and a stratum corneum that was successfully colonised by S. pseudintermedius after topical application. The number of colony forming units of S. pseudintermedius showed a 2 log increase after 24 h colonisation, indicating that the explant supported bacterial growth. By contrast, co-treatment with S. felis C4 live bacteria and its sterile protein product significantly reduced the growth of a methicillin-susceptible (ST540, p = 0.0357) and a methicillin-resistant (MR) strain (ST71, p = 0.0143) of S. pseudintermedius. No detectable bacteria were recovered from or visualised on skin 24 h posttreatment with the S. felis C4 sterile protein product., Conclusions and Clinical Relevance: Using a novel canine explant model, we demonstrate that the S. felis C4 strain inhibits the growth of S. pseudintermedius and that it is a promising candidate for a new probiotic therapy to treat cutaneous infections caused by S. pseudintermedius, including MR strains., (© 2024 ESVD and ACVD.)

A 1.5-year-old American quarter horse gelding (case 1) and an 11-month-old American quarter horse filly (case 2) were presented for acute onset pelvic lameness and lethargy. Case 1 had nasal discharge, while case 2 developed rapid muscle atrophy. Both horses had elevated serum creatine kinase activity. The horses showed similar polyphasic histiocytic and lymphoplasmacytic myositis with necrosis, mineralization, and regeneration. Additionally, case 1 had Streptococcus equi subsp. e qui -induced suppurative retropharyngeal lymphadenitis with renal purpura hemorrhagica and myoglobinuric nephropathy. A focal pulmonary abscess caused by Actinobacillus equuli was found in case 2. Genetic testing revealed case 1 as heterozygous and case 2 as homozygous for the E321G MYH1 variant, supporting the diagnosis of myosin heavy-chain myopathy, with concomitant bacterial disease as potential triggers., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

The skin covers the external surface of animals, and it is constantly exposed to and inhabited by different microorganisms, including bacteria. Alterations in the skin barrier allow commensal and/or pathogenic bacteria to proliferate and penetrate deep into the lower layers of the skin. Being the first barrier to the external environment, the skin is prone to injuries, allowing the penetration of microorganisms that may lead to severe deep infections. Companion animals, especially dogs, are prone to bacterial infections, often secondary to allergic dermatitis. When environmental conditions are unfavorable, horses, cattle, sheep, and goats can develop superficial infections, such as those caused by Dermatophilus congolensis . Deep inflammation is commonly caused by Mycobacterium spp., which results in granulomatous to pyogranulomatous dermatitis and panniculitis. Likewise, bacteria such as Nocardia spp. and Actinomyces spp. can cause deep pyogranulomatous inflammation. Bacteria that lead to deep necrotizing lesions (eg, necrotizing fasciitis/flesh-eating bacteria) can be severe and even result in death. This review includes an overview of the most common cutaneous bacterial infections of domestic animals, highlighting the main features and histologic morphology of the bacteria, cutaneous structures involved, and the type of inflammatory infiltrates., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Parasites of the Cylicospirura genus are known to affect domestic and wild carnivores by causing the formation of nodules within the gastric mucosa and pyloric region of parasitized animals. C. felineus is a specimen of this genus that has been reported in Brazil in animal species such as Leopardus geoffroyi and Puma concolor. However, as far as the authors of the present study are aware, reports of C. felineus in jaguarundis (Puma yagouaroundi) do not yet exist. This wild feline species native to the Americas is found only in a few countries - and it is possibly extinct in others, such as the United States. In Brazil, the P. yagouaroundi species is classified as vulnerable by government environmental agencies. Consequently, identifying the diseases and their relevance to this species is of utmost importance for P. yagouaroundi's preservation. This study aims to describe the histopathological lesions found in jaguarundis parasitized by the genus Cylicospirura, and to identify the parasitic species observed in these animals. Eight specimens of P. yagouaroundi necropsied between 2010 and 2020 in the Laboratory of Veterinary Pathology of the Federal University of Paraná (UFPR) in Palotina, Brazil, were studied. Seven specimens were wildlife roadkills, and one was from the Municipal Zoo of Cascavel, Paraná, Brazil. Seven of the necropsied animals presented - in the greater curvature of the stomach, near the cardia - one or more parasitic nodules of 0.5 to 3.0 cm in diameter that contained several intralesional reddish filiform parasites. Histologically, these nodules were characterized as transmural parasitic granulomas surrounded by reaction with deposition of dense connective tissue. The parasitological evaluations by light and scanning electron microscopy identified morphological C. felineus' characteristics through the presence of unequal spicules in males, the position of the vulva, and location of the pedunculated papillae. Despite the gastric lesion caused by the parasite, the apparent low pathogenicity to the gastrointestinal system of the evaluated animals, massive infections or large nodules can lead to death - other members of the Spirocercidae family are known to cause organ rupture, esophageal obstructions, and mesenchymal neoplasms. Therefore, C. felineus should be included in the list of gastric parasites with pathogenic potential in the species P. yagouaroundi., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

American trypanosomiasis is caused by the zoonotic protozoa Trypanosoma cruzi and primarily results in heart disease. Organisms also infect the central nervous system (CNS). The Texas A&M University veterinary teaching hospital archive was searched for dogs with CNS disease with intralesional protozoal amastigotes. This study summarizes 4 cases of dogs with disseminated trypanosomiasis and CNS involvement confirmed by quantitative polymerase chain reaction (qPCR) with T. cruzi primers. Clinical signs included lethargy, respiratory distress, tetraparesis, and seizures. Central nervous system lesions included meningeal congestion (1/4), necrosis with hemorrhage in the spinal cord gray and white matter (2/4), and histiocytic meningoencephalitis (4/4), and meningomyelitis (2/4) with intralesional and intracellular protozoal. Genotyping identified 1 case of T. cruzi discrete typing unit (DTU) TcI and 2 cases as TcIV, both are common variants in the United States. Trypanosomiasis should be considered a differential diagnosis for dogs with CNS signs in T. cruzi -endemic areas.

Reports of compound odontomas in rats are very rare. A 14-month-old adult male Sprague Dawley rat was found to have a hard mass associated with the caudal aspect of the left mandible. After 2 weeks of observation, the rat was euthanized due to the mass growing significantly in size and the rat losing >20% of its body weight. Grossly, the mass was well-circumscribed, 3.7 × 3 × 1.2 cm, hard and heterogeneously coloured white, tan and red. The mass was restricted to the mandibular bone and did not involve surrounding subcutaneous tissue. On cut surface, the mass was a similar colour and brittle. Histologically, there were numerous proto-teeth embedded in ossified stroma. Each proto-tooth had a central mesenchyme pulp surrounded by columnar odontoblasts and dentine matrix. The dentine was often bordered by enamel matrix, which was occasionally bounded by ameloblasts. These histological findings were consistent with a compound odontoma. This is the first report of a spontaneous compound odontoma in the caudal mandible of a rat., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Networks and graphs provide a simple but effective model to a vast set of systems in which building blocks interact throughout pairwise interactions. Unfortunately, such models fail to describe all those systems in which building blocks interact at a higher order. Higher-order graphs provide us the right tools for the task, but introduce a higher computing complexity due to the interaction order. In this paper we analyze the interplay between the structure of a directed hypergraph and a linear dynamical system, a random walk, defined on it. How can one extend network measures, such as centrality or modularity, to this framework? Instead of redefining network measures through the hypergraph framework, with the consequent complexity boost, we will measure the dynamical system associated to it. This approach let us apply known measures to pairwise structures, such as the transition matrix, and determine a family of measures that are amenable to such a procedure.

When the threat of COVID-19 became widely acknowledged, many hoped that this pandemic would squash "the anti-vaccine movement". However, when vaccines started arriving in rich countries at the end of 2020, it appeared that vaccine hesitancy might be an issue even in the context of this major pandemic. Does it mean that the mobilization of vaccine-critical activists on social media is one of the main causes of this reticence to vaccinate against COVID-19? In this paper, we wish to contribute to current work on vaccine hesitancy during the COVID-19 pandemic by looking at one of the many mechanisms which can cause reticence towards vaccines: the capacity of vaccine-critical activists to influence a wider public on social media. We analyze the evolution of debates over the COVID-19 vaccine on the French Twittosphere, during two first years of the pandemic, with a particular attention to the spreading capacity of vaccine-critical websites. We address two main questions: 1) Did vaccine-critical contents gain ground during this period? 2) Who were the main actors in the diffusion of these contents? While debates over vaccines experienced a tremendous surge during this period, the share of vaccine-critical contents in these debates remains stable except for a limited number of short periods associated with specific events. Secondly, analyzing the community structure of the re-tweets hyper-graph, we reconstruct the mesoscale structure of the information flows, identifying and characterizing the major communities of users. We analyze their role in the information ecosystem: the largest right-wing community has a typical echo-chamber behavior collecting all the vaccine-critical tweets from outside and recirculating it inside the community. The smaller left-wing community is less permeable to vaccine-critical contents but, has a large capacity to spread it once adopted., Competing Interests: The authors have declared that no competing interests exist.

When access to diagnosis and treatment of tuberculosis is disrupted by poverty or unequal access to health services, marginalized communities not only endorse the burden of preventable deaths, but also suffer from the dramatic consequences of a disease which impacts one's ability to access education and minimal financial incomes. Unfortunately, these pockets are often left unrecognized in the flow of data collected in national tuberculosis reports, as localized hotspots are diluted in aggregated reports focusing on notified cases. Such system is therefore profoundly inadequate to identify these marginalized groups, which urgently require adapted interventions. We computed an estimated incidence-rate map for the South-Kivu province of the Democratic Republic of Congo, a province of 5.8 million inhabitants, leveraging available data including notified incidence, level of access to health care and exposition to identifiable risk factors. These estimations were validated in a prospective multi-centric study. We could demonstrate that combining different sources of openly-available data allows to precisely identify pockets of the population which endorses the biggest part of the burden of disease. We could precisely identify areas with a predicted annual incidence higher than 1%, a value three times higher than the national estimates. While hosting only 2.5% of the total population, we estimated that these areas were responsible for 23.5% of the actual tuberculosis cases of the province. The bacteriological results obtained from systematic screenings strongly correlated with the estimated incidence (r = 0.86), and much less with the incidence reported by epidemiological reports (r = 0.77), highlighting the inadequacy of these reports when used alone to guide disease control programs., (© 2022. The Author(s).)

We consider state-aggregation schemes for Markov chains from an information-theoretic perspective. Specifically, we consider aggregating the states of a Markov chain such that the mutual information of the aggregated states separated by T time steps is maximized. We show that for T=1 this recovers the maximum-likelihood estimator of the degree-corrected stochastic block model as a particular case, which enables us to explain certain features of the likelihood landscape of this generative network model from a dynamical lens. We further highlight how we can uncover coherent, long-range dynamical modules for which considering a timescale T≫1 is essential. We demonstrate our results using synthetic flows and real-world ocean currents, where we are able to recover the fundamental features of the surface currents of the oceans.

Mycobacterium bovis Bacillus Calmette-Guérin (BCG) instillations are used in bladder cancer treatment. Adverse effects can occur. Osteoarticular complications are mainly reactive arthritis, but true infections have been described, such as vertebral osteomyelitis. We made a review of M. bovis BCG vertebral osteomyelitis after instillations for bladder cancer using PubMed search. We added three new French cases. Twenty-seven cases of BCG vertebral osteomyelitis had been reported on PubMed. Of the 30 cases, all were male, averaging 73.4 ± 8.7 years old. Median time between diagnosis and first and last instillation was 22.5 and 14 months respectively. Half of vertebral osteomyelitis was thoracic and lumbar in the other half. Sensitivo-motor deficit was present at diagnosis in 42% of cases. Other infectious locations were common, mainly infectious abdominal aortic aneurysms (20%). Rifampicin, ethambutol and isoniazid were the usual therapy. Poor outcomes were reported with 50% of one or more spine surgery. M. bovis BCG vertebral osteomyelitis following bladder instillation for bladder cancer is a rare complication. However, the late onset of back pain after instillations differentiates them from reactive arthritis. Concomitant septic location such as infectious abdominal aortic aneurysms must be known.

Background: Global roll-out of rapid molecular assays is revolutionising the diagnosis of rifampicin resistance, predictive of multidrug-resistance, in tuberculosis. However, 30% of the multidrug-resistant (MDR) strains in an eSwatini study harboured the Ile491Phe mutation in the rpoB gene, which is associated with poor rifampicin-based treatment outcomes but is missed by commercial molecular assays or scored as susceptible by phenotypic drug-susceptibility testing deployed in South Africa. We evaluated the presence of Ile491Phe among South African tuberculosis isolates reported as isoniazid-monoresistant according to current national testing algorithms., Methods: We screened records of 37 644 Mycobacterium tuberculosis positive cultures from four South African provinces, diagnosed at the National Health Laboratory Service-Dr George Mukhari Tertiary Laboratory, to identify isolates with rifampicin sensitivity and isoniazid resistance according to Xpert MTB/RIF, GenoType MTBDRplus, and BACTEC MGIT 960. Of 1823 isolates that met these criteria, 277 were randomly selected and screened for Ile491Phe with multiplex allele-specific PCR and Sanger sequencing of rpoB. Ile491Phe-positive strains (as well as 17 Ile491Phe-bearing isolates from the eSwatini study) were then tested by Deeplex-MycTB deep sequencing and whole-genome sequencing to evaluate their patterns of extensive resistance, transmission, and evolution., Findings: Ile491Phe was identified in 37 (15%) of 249 samples with valid multiplex allele-specific PCR and sequencing results, thus reclassifying them as MDR. All 37 isolates were additionally identified as genotypically resistant to all first-line drugs by Deeplex-MycTB. Six of the South African isolates harboured four distinct mutations potentially associated with decreased bedaquiline sensitivity. Consistent with Deeplex-MycTB genotypic profiles, whole-genome sequencing revealed concurrent silent spread in South Africa of a MDR tuberculosis strain lineage extending from the eSwatini outbreak and at least another independently emerged Ile491Phe-bearing lineage. Whole-genome sequencing further suggested acquisition of mechanisms compensating for the Ile491Phe fitness cost, and of additional bedaquiline resistance following the introduction of this drug in South Africa., Interpretation: A substantial number of MDR tuberculosis cases harbouring the Ile491Phe mutation in the rpoB gene in South Africa are missed by current diagnostic strategies, resulting in ineffective first-line treatment, continued amplification of drug resistance, and concurrent silent spread in the community., Funding: VLIR-UOS, National Research Foundation (South Africa), and INNOVIRIS., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Livestock poisoning by plants is a frequent occurrence which determines severe losses, such as the fall in the milk and meat production, the cost of expensive treatments, the state of immunosuppression, or even the animal's death. Cattle ingest toxic plants only when there is food shortage, when they cannot select what they eat, or when they ingest food for preference, which is the case of Hovenia dulcis fruits, very rich in sucrose. This plant is widely distributed in the southern and southeastern Brazilian regions. In literature, there are some cases of severe human liver injury associated with a long-term of H. dulcis leaf and fruit tea intake, and only one report regarding spontaneous poisoning of goats caused by this plant ingestion. However, its toxic effects associated with spontaneous ingestion by cattle have never been reported. This paper reports the first case of spontaneous poisoning in cattle by H. dulcis, which occurred in a dairy farm in southwest Paraná, Brazil. Three cattle individuals showed anorexia, ruminal atony, severe diarrhea and neurological tournament, head pressing, blindness, ataxia, and circling. The necropsy of the animals was done, and the remaining alterations were restricted to the digestive system and brain. The clinical signs presented by the animals are characteristic of polioencephalomalacia (PEM), caused by changes in the thiamine metabolism. Furthermore, clinical signs, gross, and microscopic lesions as well as the large amount of the plant throughout the digestive segment led to a diagnosis.

Protein energy landscapes are highly complex, yet the vast majority of states within them tend to be invisible to experimentalists. Here, using site-directed mutagenesis and exploiting the simplicity of tandem-repeat protein structures, we delineate a network of these states and the routes between them. We show that our target, gankyrin, a 226-residue 7-ankyrin-repeat protein, can access two alternative (un)folding pathways. We resolve intermediates as well as transition states, constituting a comprehensive series of snapshots that map early and late stages of the two pathways and show both to be polarized such that the repeat array progressively unravels from one end of the molecule or the other. Strikingly, we find that the protein folds via one pathway but unfolds via a different one. The origins of this behavior can be rationalized using the numerical results of a simple statistical mechanics model that allows us to visualize the equilibrium behavior as well as single-molecule folding/unfolding trajectories, thereby filling in the gaps that are not accessible to direct experimental observation. Our study highlights the complexity of repeat-protein folding arising from their symmetrical structures; at the same time, however, this structural simplicity enables us to dissect the complexity and thereby map the precise topography of the energy landscape in full breadth and remarkable detail. That we can recapitulate the key features of the folding mechanism by computational analysis of the native structure alone will help toward the ultimate goal of designed amino-acid sequences with made-to-measure folding mechanisms-the Holy Grail of protein folding.

We describe a new method for peptide sequencing based on the mapping of the interpretation of tandem mass spectra onto the analysis of the equilibrium distribution of a suitably defined physical model, whose variables describe the positions of the fragmentation sites along a discrete mass index. The model is governed by a potential energy function that, at present, we derive ad hoc from the distribution of peaks in a data set of experimental spectra. The statistical-physics perspective prompts for a consistent and unified approach to de novo and database-search methods, which is a distinctive feature of this approach over alternative ones: the characterization of the ground state of the model allows the de novo identification of the precursor peptide; the study of the thermodynamic variables as a function of the (fictitious) temperature gives insight on the quality of the prediction, while the probability profiles at nonzero temperature reveal, on one hand, which fragments are more reliably predicted. On the other hand, they can be used as a spectrum-adapted, a posteriori score for database search. Results obtained with two different test data sets reveal a performance similar to that of other de novo and database-search methods, which is reasonable, given the lack of an aggressive optimization of the energy function at this stage. An important feature of the method is that it is quite general and can be applied with different choices of the energy function: we discuss its possible improvements and generalizations.

Quantum mechanics still provides new unexpected effects when considering the transport of energy and information. Models of continuous time quantum walks, which implicitly use time-reversal symmetric Hamiltonians, have been intensely used to investigate the effectiveness of transport. Here we show how breaking time-reversal symmetry of the unitary dynamics in this model can enable directional control, enhancement, and suppression of quantum transport. Examples ranging from exciton transport to complex networks are presented. This opens new prospects for more efficient methods to transport energy and information.

We apply the Wako-Saito-Muñoz-Eaton model to the study of myotrophin, a small ankyrin repeat protein, whose folding equilibrium and kinetics have been recently characterized experimentally. The model, which is a native-centric with binary variables, provides a finer microscopic detail than the Ising model that has been recently applied to some different repeat proteins, while being still amenable for an exact solution. In partial agreement with the experiments, our results reveal a weakly three-state equilibrium and a two-state-like kinetics of the wild-type protein despite the presence of a nontrivial free-energy profile. These features appear to be related to a careful "design" of the free-energy landscape, so that mutations can alter this picture, stabilizing some intermediates and changing the position of the rate-limiting step. Also, the experimental findings of two alternative pathways, an N-terminal and a C-terminal one, are qualitatively confirmed, even if the variations in the rates upon the experimental mutations cannot be quantitatively reproduced. Interestingly, the folding and unfolding pathways appear to be different, even if closely related: a property that is not generally considered in the phenomenological interpretation of the experimental data.

We report the case of a 41 year-old male who came to the emergency room with a complaint of abdominal pain, and was diagnosed to have an acute obstructive abdomen due to a right inguinal hernia incarceration. During surgery, an intestinal granulomatous inflammation was observed adhered to the hernial sac. The histopathologic study confirmed the diagnosis of tuberculosis. We present a review of the different clinical forms of intestinal tuberculosis and the difficulties encountered in the differential diagnosis of such, emphasizing the uncommon presentation described in our patient.