Search Results (73)

Pseudomonas aeruginosa is a highly adaptable opportunistic pathogen with significant clinical relevance in both human and veterinary medicine. Despite its well-documented role in hospital-acquired infections in human healthcare settings, its persistence and transmission within veterinary clinics remain underexplored. This review highlights the overlooked status of veterinary facilities as environmental reservoirs and amplification points for multidrug-resistant (MDR) P. aeruginosa, emphasizing their relevance to One Health surveillance. We examine the bacterium’s environmental survival strategies, including biofilm formation, resistance to disinfectants, and tolerance to nutrient-poor conditions that facilitate the long-term colonization of moist surfaces, drains, medical equipment, and plumbing systems. Common transmission vectors are identified, including asymptomatic animal carriers, contaminated instruments, and the hands of veterinary staff. The review synthesizes current data on antimicrobial resistance in environmental isolates, revealing frequent expression of efflux pumps and mobile resistance genes, and documents the potential for zoonotic transmission to staff and pet owners. Key gaps in environmental monitoring, infection control protocols, and genomic surveillance are identified, with a call for standardized approaches tailored to the veterinary context. Control strategies, including mechanical biofilm disruption, disinfectant cycling, effluent monitoring, and staff hygiene training, are evaluated for feasibility and impact. The article concludes with a One Health framework outlining cross-species and environmental transmission pathways. It advocates for harmonized surveillance, infrastructure improvements, and intersectoral collaboration to reduce the risk posed by MDR P. aeruginosa within veterinary clinical environments and beyond. By addressing these blind spots, veterinary facilities can become proactive partners in antimicrobial stewardship and global resistance mitigation. Full article

Feline calicivirus (FCV) is a highly contagious pathogen widely circulating in cat populations. FCV has been shown to be able to evade the host immune response through different mechanisms. As a result, following the acute phase of infection, some cats remain persistently infected or experience reinfection cycles with variants of the same strain or with distinct field FCVs. These animals may become asymptomatic carriers, assuming a critical role in virus transmission and posing a significant risk to susceptible cats, particularly in high-density settings. Typical clinical signs of FCV infection include upper respiratory tract disease, oral ulcerations, salivation, and gingivostomatitis. In some cases, FCV infection has also been linked to a range of other clinical manifestations, including severe virulent systemic disease with high mortality rates. Indeed, FCV diversity and evolution have led to the emergence of new genetic, antigenic, and phenotypic variants, challenging disease control. This review provides a comprehensive synthesis of FCV, including its molecular biology, epidemiology, pathogenesis and clinical manifestations. Additionally, the role of vaccination and direct prophylaxis is critically evaluated. An integrated approach is essential to mitigate FCV transmission and disease burden in feline populations. Full article

A backyard cat with symptoms of otitis was transferred to a veterinary clinic in Central Greece. A sample was obtained and P. aeruginosa was isolated. The strain exhibited an extensively drug-resistant (XDR) profile, as it was non-susceptible to all tested agents except colistin. DNA extraction and whole-genome sequencing (WGS) were performed using a robotic extractor and Ion Torrent technology, respectively. The genome was assembled and screened for resistance and virulence determinants. The isolate belonged to the high-risk clone ST308 with a total of 67 antibiotic resistance genes (ARGs) and 221 virulence factor-related genes being identified. No plasmids were detected. The metallo-beta-lactamase (MBL) bla_NDM-1 gene and 46 efflux pumps were included in the strain’s resistome. Both ARGs conferring tolerance to disinfecting agents and biofilm-related genes were identified, associated with the ability of this clone to adapt and persist in healthcare facilities. This case highlights the risk of relevant bacterial clones spreading in the community and even being transmitted to companion animals, causing challenging opportunistic infections to susceptible individuals, while others may become carriers, further spreading the clones to their owners, other animals and the environment. Full article

Canine distemper is caused by a morbillivirus similar to others that affect livestock and humans. The increase in host range and its persistence in wildlife reservoirs complicate eradication considerably. Canine distemper virus has been reported in wildlife in Mexico since 2007. Dogs were previously considered the main reservoirs, but high vaccination coverage in the USA has helped control the disease, and racoons (Procyon lotor) are now recognized as the main reservoirs of the agent in the USA, since they live in high densities in urban environments (peridomestic), where contact with domestic and wildlife species is common. Racoons are now considered to spread CDV in wildlife species and zoo animals. Mexico is home to at least two wildlife species that have been reported as carriers of the CDV infection in studies in the USA. Raccoons and Coyotes are distributed in several Mexican states and could play the same reservoir role as for the US. In addition, the increase in non-traditional pets expands the availability of susceptible individuals to preserve CDV in domiciliary and peri-domiciliary environments, contributing to the spread of the disease. Combined with incomplete vaccination coverage in domestic canids, this could contribute to maintaining subclinical infections. Infected pets with incomplete vaccination schedules could also spread CDV to other canines or wildlife coexisting species. In controlled habitats, such as flora and fauna sanctuaries, protected habitats, zoo collections, etc., populations of wildlife species and stray dogs facilitate the spread of CDV infection, causing the spilling over of this infectious agent. Restricting domestic pets from wildlife habitats reduces the chance of spreading the infection. Regular epidemiological surveillance and specific wildlife conservation practices can contribute to managing threatened species susceptible to diseases like CDV. This may also facilitate timely interventions in companion animals which eventually minimize the impact of this disease in both scenarios. Aim: The review discusses the circulation of CDV in wildlife populations, and highlights the need for epidemiological surveillance in wildlife, particularly in endangered wildlife species from Mexico. Through an extensive review of recent scientific literature about CDV disease in wildlife that has been published in local and international databases, the findings were connected with the current needs of information from a local to global perspective, and conclusions were made to broaden the context of Mexican epidemiological scenarios as closely related to the neighboring regions. Full article

Hemoglobin-based oxygen carriers (HBOCs) represent a promising alternative to traditional blood transfusions, offering the advantages of extended shelf life and avoiding blood compatibility limitations and infection risks. Positive effects of hemoglobin-based oxygen carriers (HBOCs) on hemorrhagic shock have been researched across various animal species, including swine, rats, rabbits, guinea pigs, and dogs. As previously described, HBOCs based on ovine hemoglobin display better efficiency in the context of hemorrhagic shock compared to those based on the more commonly used bovine hemoglobin. This was evidenced through higher survival rates and more favorable histopathological and immunological outcomes. The vascular effects of ovine hemoglobin polymerized with glutaraldehyde exposure included the absence of hypertension, minimal endothelial damage with slight alterations in inducible nitric oxide synthase (iNOS), and reduced vascular inflammation mediated by interleukin-10 (IL-10). Ovine hemoglobin has emerged as a particularly promising raw material for the development of HBOCs, surpassing bovine and human hemoglobin due to its advantages in availability and efficacy. Furthermore, reducing oxidative stress by polymerizing hemoglobin with glutaraldehyde is most effective with ovine hemoglobin compared to bovine hemoglobin. This study evaluates the effectiveness of ovine hemoglobin polymerized with glutaraldehyde in managing hemorrhagic shock in rabbits, with a focus on its ability to maintain blood pressure, support oxygen transport, and assess potential systemic and oxidative responses. Fifteen adult New Zealand white rabbits, divided into three equal groups, were included in this study: a negative control group transfused with colloid solutions, a positive control group treated with autotransfusion, and a group receiving HBOCs. All groups underwent a hemorrhagic shock protocol, with 40% of their total blood volume withdrawn under deep anesthesia, followed by transfusions 30 min later. Vital parameters, including invasive arterial blood pressure, heart rate, and end-tidal CO₂, were measured throughout the experimental procedures. Arterial blood gas samples were collected before the procedures, after hemorrhagic shock induction, and at the conclusion of the transfusion. In summary, HBOCs offer a promising solution for oxygen delivery, but their effects on blood chemistry, particularly CO₂ and lactate levels, must be considered. Although no direct oxygenation issues were observed in experimental models, elevated CO₂ levels and the interference of HBOCs with lactate measurements emphasize the importance of vigilant clinical monitoring. Polymerized hemoglobin provides a non-nephrotoxic alternative, but challenges persist in preventing nitric oxide scavenging and ensuring effective oxygen delivery. Full article

Bovine leukemia virus (BLV) is classified as a Deltaretrovirus and shows close genomic and biological similarities with human T-cell leukemia viruses (HTLVs). It serves as the etiological agent for enzootic bovine leukosis (EBL), which stands as the most prevalent neoplastic disease affecting cattle globally. Additionally, BLV has been identified as a potential zoonotic pathogen, although the risk to human health remains a subject of ongoing research. The insidious nature of BLV lies in its predominantly subclinical presentation; the majority of BLV-infected cattle show no apparent symptoms. This subclinical nature poses challenges for disease detection and control, as infected animals can remain unnoticed carriers, contributing to the silent spread of the virus within herds. This characteristic also underscores the importance of surveillance and early detection strategies to monitor BLV prevalence and mitigate its spread. Despite concerted efforts in some regions to implement eradication programs, BLV continues to maintain a high prevalence worldwide. The persistence of BLV in cattle populations highlights the need for innovative and integrated approaches to control and manage the disease effectively. The development of a BLV vaccine represents a significant breakthrough in the fight against BLV transmission. A successful vaccine can not only reduce the incidence of BLV infection but also minimize the associated economic losses linked to reduced milk production, reproductive issues, and the premature culling of infected animals. Therefore, a comprehensive understanding of BLV, encompassing its origin, evolutionary patterns, epidemiology, risk factors, and control strategies, is pivotal. Such knowledge serves as the foundation for the development of effective vaccines, diagnostic tools, and control measures. Through this review, we aim to consolidate and present this multifaceted understanding of BLV, providing valuable insights and guidance for researchers, veterinarians, and policymakers involved in BLV prevention and control efforts globally. Full article

Pine wilt disease, caused by the nematode Bursaphelenchus xylophilus, poses a significant threat to pine forests worldwide. Understanding the dynamics of its spread is crucial for effective disease management. In this study, we investigated the involvement of asymptomatic carrier trees in the expansion of pine wilt disease through a series of experiments. Cage-releasing experiments revealed that sexually immature Japanese pine sawyer beetles, Monochamus alternatus, feeding on healthy pine branches drops only a minimal number of nematodes (primary infection). However, sexually mature beetles, still harboring numerous nematodes, fly to weakened trees for breeding and extend their feeding activities to healthy pines around weakened trees, infecting them with nematodes and thus spreading the disease further. Inoculation experiments on field-planted black pine seedlings demonstrated that even a small number of nematodes can lead to a high occurrence of asymptomatic carrier trees. Our findings suggest that nematode infections transmitted by sexually mature Monochamus beetles significantly contribute to the expansion of pine wilt damage and play a crucial role in the persistence of asymptomatic carrier trees. This conclusion is based on cage-release experiments demonstrating nematode transmission by mature beetles and inoculation experiments highlighting the conditions leading to asymptomatic carrier trees. Full article

Pseudostellaria heterophylla (Miq.) Pax (P. heterophylla) was a valued traditional Chinese herbal medicine. Previous studies have shown that P. heterophylla TuMV spreads during the vegetative propagation cycle using tuberous roots as carriers. However, the transmission mechanism of TuMV in P. heterophylla and its effects on host growth remain to be elucidated. In this study, virus-free P. heterophylla culture seedlings were infected with control, TuMV-ZR, and TuMV-ZR-EGFP, thereby resulting in the initial infection cycle of IF1 (TIF1, TEIF1) and control NIF1, and used these roots to propagate the subsequent infection cycle IF2 (TIF2, TEIF2) and control NIF2. The transmission of TuMV-ZR seedlings was tracked by EGFP signal, and their yield, quality, and resistance were analyzed simultaneously in the critical growth period of the plants. The results indicated that TuMV-ZR accumulated in the tuberous roots of IF1 plants, subsequently migrated to IF2 during seedling growth, and was re-stored in IF2 tuberous roots, thereby forming a simple virus transmission cycle. Meanwhile, the tuberous roots of IF1 and IF2 P. heterophylla showed lower fresh weight, dry weight, soluble sugar, and saponin levels compared to NIF1 and NIF2, respectively. TuMV caused a significant reduction in chlorophyll synthesis in IF1 and IF2 P. heterophylla, resulting in impairment to their photosynthetic organs and efficiency. The measurement of stress resistance in IF1 and IF2 P. heterophylla revealed that continuous viral infection disrupted antioxidant enzyme activity, increased the content of MDA, enhanced the activity of PAL, and elevated the levels of intracellular osmotic substances in both propagation cycles. The findings indicated that the accumulation of the TuMV-ZR virus during two successive vegetative propagation cycles induced physiological stress, impaired photosynthesis, and caused progressive yield and quality decline with each cycle. This study systematically examined the impact of TuMV-ZR persistence during vegetative propagation on key physiological and biochemical indices in P. heterophylla, providing critical data to clarify vegetative-propagation-mediated germplasm degradation. Full article

Introduction: An ambulance used by an emergency medical service team is the workplace of specialised medical personnel, providing daily transportation for patients in life-threatening conditions, from all walks of life, with numerous diseases and injuries. MRSA (methicillin-resistant Staphylococcus aureus) strains are classified as Gram-positive cocci, characterised primarily by their multidrug resistance. Infections caused by S. aureus have a low treatment success rate and are associated with persistent carrier state. This study aimed to isolate MRSA and MSSA (methicillin-sensitive Staphylococcus aureus) in the emergency vehicle and determine drug resistance of these isolates. Materials and Methods: This study involved an ambulance vehicle operated in central Poland. A total of 39 swabs were taken and evaluated from inside the ambulance on permanent duty. The isolates were analysed using catalase and coagulase assays, Gram staining, culturing on Chapman medium, growth evaluation on agar with 5% sheep blood, and assessing the strains’ sensitivities to selected antibiotics. Material was collected from 13 designated points located in the medical compartment and driver’s cabin. Results: S. aureus bacteria were detected in 51.28% of the samples, 40% of which were MRSA strains. Despite the application of high disinfection standards for the interior of the ambulance, it was not possible to kill all S. aureus strains, which may be because the pathogens in question produce a biofilm that effectively allows them to survive on various surfaces, including those disinfected. Almost 100% of the MRSA isolates were resistant to antibiotics from the β-lactam group (penicillin, ticarcillin, cefotaxime, and cefoxitin), the macrolide group (erythromycin) and the lincosamide group (clindamycin). However, only a few MRSA strains proved resistant to streptomycin (12.5%) and ciprofloxacin (37.5%). β-lactam antibiotics, such as cefotaxime (100% resistant strains) and penicillin (58% resistant strains), were also ineffective against MSSA. Although MSSA isolates showed slight resistance to ticarcillin and erythromycin (33.3%) and clindamycin (25%), the remaining antibiotics proved effective (no resistant strains). Conclusions: Among the isolated strains, the greatest resistance to β-lactam antibiotics and erythromycin was observed. Multidrug-resistant strains of S. aureus were found in the emergency medical system. Even the MSSA strains detected in the studied ambulance showed resistance to some of the antibiotics used. The prevalence of S. aureus strains within ambulances indicates the need for a high hygiene level in daily prehospital work with patients. Full article

Salmonella enterica infections can significantly impact the health and productivity of dairy cattle. Asymptomatic carriage of Salmonella can make it difficult to identify and monitor this pathogen across a herd. Therefore, a more focused Salmonella census on dairy farms is needed to better understand the dynamics of asymptomatic carriage. Here, we monitored the prevalence of Salmonella enterica on a dairy operation in Wisconsin, USA. Fecal samples were collected over 12 months from cattle and the farm environment, subjected to Salmonella isolation, serogrouped, and tested for antibiotic resistance. Salmonella was highly prevalent on this farm, with an average of 90% of the cattle being carriers. Total recovery of Salmonella from environmental samples ranged from 40 to 90%. Four serogroups were identified on the farm, with K being most common in cattle and C being most common in the environment. Antibiotic resistance was tested against eight antibiotics and was found to be highest for neomycin (44.5%) and sulfadimethoxine (86.3%). Our data show that serogroups associated with asymptomatic carriages are persistent and highly prevalent, with niche specificity to different locations. These results provide useful information for studying within-herd transmission of Salmonella and contributes to our understanding of transmission risks within the farm ecosystem. Full article

Cells have developed various mechanisms to counteract viral infections. In an evolutionary arms race, cells mobilize cellular restriction factors to fight off viruses, targeted by viral factors to facilitate their own replication. The hepatitis B virus (HBV) is a small dsDNA virus that causes acute and chronic infections of the liver. Its genome persists in the nuclei of infected hepatocytes as a covalently closed circular DNA (cccDNA) minichromosome, thus building up an episomal persistence reservoir. The chromosomal maintenance complex SMC5/6 acts as a restriction factor hindering cccDNA transcription, whereas the viral regulatory protein HBx targets SMC5/6 for proteasomal degradation, thus relieving transcriptional suppression of the HBV minichromosome. To date, no curative therapies are available for chronic HBV carriers. Knowledge of the factors regulating the cccDNA and the development of therapies involving silencing the minichromosome or specifically interfering with the HBx-SMC5/6 axis holds promise in achieving sustained viral control. Here, we summarize the current knowledge of the mechanism of SMC5/6-mediated HBV restriction. We also give an overview of SMC5/6 cellular functions and how this compares to the restriction of other DNA viruses. We further discuss the therapeutic potential of available and investigational drugs interfering with the HBx-SMC5/6 axis. Full article

The human phosphatase and tensin homolog (PTEN) is a tumor suppressor. A slight deficiency in PTEN might cause cancer susceptibility and progression. Infection by the liver fluke Clonorchis sinensis could lead to persistent loss of PTEN in cholangiocarcinoma. However, the mechanism of PTEN loss and its malignant effect on cholangiocarcinoma have not yet been elucidated. Extracellular vesicles secreted by Clonorchis sinensis (CS-EVs) are rich in microRNAs (miRNAs) and can mediate communication between hosts and parasites. Herein, we delved into the miRNAs present in CS-EVs, specifically those that potentially target PTEN and modulate the progression of cholangiocarcinoma via ferroptosis mechanisms. CS-EVs were extracted by differential ultra-centrifugation for high-throughput sequencing of miRNA. Lentiviral vectors were used to construct stably transfected cell lines. Erastin was used to construct ferroptosis induction models. Finally, 36 miRNAs were identified from CS-EVs. Among them, csi-miR-96-5p inhibited PTEN expression according to the predictions and dual luciferase assay. The CCK-8 assay, xenograft tumor assays and transwell assay showed that csi-miR-96-5p overexpression and PTEN knockout significantly increased the proliferation and migration of cholangiocarcinoma cells and co-transfection of PTEN significantly reversed the effect. In the presence of erastin, the cell proliferation and migration ability of the negative transfection control group were significantly impaired, although they did not significantly change with transfection of csi-miR-96-5p and PTEN knockout, indicating that they obtained ferroptosis resistance. Mechanistically, csi-miR-96-5p and PTEN knockout significantly inhibited ferroptosis through a decrease in ferrous ion (Fe²⁺) and malondialdehyde (MDA), and an increase in glutathione reductase (GSH), Solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4). In conclusion, loss of PTEN promoted the progression of cholangiocarcinoma via the ferroptosis pathway and csi-miR-96-5p delivered by CS-EVs may mediate this process. Full article

Adolescent carriers of the Aggregatibacter actinomycetemcomitans JP2 genotype have an increased risk of developing periodontitis, due to the bacterium’s high leukotoxin (LtxA) production. LtxA contributes to marginal bone loss by killing immunity cells, thus activating the proinflammatory interleukin-1β (IL-1β), which, in turn, activates the osteoclasts. A possible strategy to prevent periodontitis might be to neutralize LtxA in JP2-infected individuals. The aim of this study was to investigate whether extracts from Matcha or Guava leaves can prolong the viability of macrophages in cell cultures by neutralizing the highly leukotoxic JP2 genotype bacteria. The A. actinomycetemcomitans JP2 genotype was pretreated with extracts from either Matcha or Guava leaves. Later, the extracts were rinsed off, before JP2 bacteria were exposed to macrophage cell cultures. The experiment was repeated, where JP2 bacteria were persistently treated with the extracts instead, i.e., the extracts were not rinsed off. The macrophage viability after bacterial exposure was analyzed and compared with that of macrophages exposed to untreated JP2 bacteria. IL-1β secretion in the cell culture medium was quantified in all group samples. Pretreatment of the A. actinomycetemcomitans JP2 genotype with Matcha or Guava leaf extracts moderately neutralized LtxA activity, which resulted in prolonged macrophage viability and decreased IL-1β secretion. These effects of prolonged macrophage viability were enhanced when extracts were persistently present during the exposure period. The results indicate that Matcha and Guava leaf extracts have effects on the virulence of the A. actinomycetemcomitans JP2 genotype that may be useful in future treatment strategies to prevent periodontitis in JP2 bacterium carriers. Full article

Persistent high-risk human papillomaviruses (HR HPVs) infection leads to the development of squamous intraepithelial lesions in cervical cells that may lead to cancer. The telomere length, telomerase activity, and species composition of the vaginal microbiome may influence the dynamic of changes and the process of carcinogenesis. In the present study, we analyze relative telomere length (RTL), relative hTERT expression (gene for the telomerase component—reverse transcriptase) in cervical smear cells and vaginal microbiomes. Total RNA and DNA were isolated from tissue samples of 109 patients from the following groups: control, carrier, low-grade or high-grade squamous intraepithelial lesion (L SIL and H SIL, respectively), and cancer. The quantitative PCR method was used to measure telomere length and telomerase expression. Vaginal microbiome bacteria were divided into community state types using morphotype criteria. Significant differences between histopathology groups were confirmed for both relative telomere length and relative hTERT expression (p < 0.001 and p = 0.001, respectively). A significant difference in RTL was identified between carriers and H SIL (p adj < 0.001) groups, as well as between carriers and L SIL groups (p adj = 0.048). In both cases, RTL was lower among carriers. The highest relative hTERT expression level was recorded in the H SIL group, and the highest relative hTERT expression level was recorded between carriers and the H SIL group (p adj < 0.001). A correlation between genotype and biocenosis was identified for genotype 16+A (p < 0.001). The results suggest that identification of HPV infection, telomere length assessment, and hTERT expression measurement together may be more predictive than each of these analyses performed separately. Full article

Human papillomavirus (HPV)-associated cervical cancer is the most common cancer among women worldwide. The treatment options are strongly related to increased infertility in women. Imiquimod (IQ) is an imidazoquinoline, which has proven antiviral effects against persistent HPV infection by activating immune cells via Toll-like receptors 7/8 when formulated in carriers, like nanogels, for topical use. An effective alternative to conventional therapies is the nanoparticle drug delivery system. We studied lipidic nanoparticles with IQ (Lipo IQ) and functionalized them with a DNA aptamer, AT11 (Lipo IQ AT11), to improve the selectivity for cervical cancer cells combined with the efficacy of essential oils. The formulations showed that the physicochemical properties are adequate for vaginal drug delivery and have antimicrobial activity at higher concentrations (with MIC₅₀ starting from 0.625%). The final formulations exhibited cytotoxicity in cancer cells, enhanced by essential oils without affecting healthy cells, resulting in less than 10% cell viability in HeLa cells and over 60% in NHDF cells. Essential oils potentiate Lipo IQ’s effectiveness, while AT11 increases the selectivity for cervical cancer cells. As suggested by the results of the permeation assay, the formulations were internalized by the cancer cells. Overall, the obtained results suggested that the synergistic effect of the essential oils and the nanosystem potentiate the cytotoxic effect of Lipo IQ and that Lipo IQ AT11 promotes selectivity towards cancer cells. Full article