Antiviral therapy in cats progressively infected with feline leukaemia virus: lessons from a series of 18 consecutive cases from Australia.

BACKGROUND: It is doubtful that any of the treatments proposed for feline leukaemia virus (FeLV) infection are effective, despite the entity being described 60 years ago. METHODS: Eighteen pet cats with progressive FeLV infections were recruited in Australia. One or more antiviral drugs were trialled in 16 cats, while two FeLV-infected cats were not handleable and served as untreated controls. Six cats were administered RetroMAD1™ only (0.5 mg/kg orally twice daily), a commercially available recombinant chimeric protein with proposed antiretroviral activity. Three cats were administered the integrase inhibitor raltegravir only (10-15 mg/kg orally twice daily), a drug used as a component of highly effective antiretroviral therapy for human immunodeficiency virus (HIV-1) infection. Three cats were administered RetroMAD1™ and raltegravir concurrently, and four cats were administered raltegravir and the reverse transcriptase inhibitor zidovudine (AZT, 5 mg/kg orally twice daily) concurrently. FeLV RNA and p27 antigen loads were measured at two timepoints (T1-2 months and T3-5 months) during therapy and compared to baseline (pretreatment) levels, to assess the response to therapy using linear modelling. The median survival time (MST) of the cats from commencement of FeLV treatment to death was also determined and compared between treatments. RESULTS: The MST for the 16 FeLV-positive cats which received antiviral therapy was 634 days, while the MST from FeLV diagnosis to death for the two untreated control cats was 780 days. In cats treated with RetroMAD1™, FeLV viral load decreased from T0 to T1-2 months (median viral load reduced from 1339 × 106 to 705 × 106 copies/mL plasma; P = 0.012), but MST was reduced compared to cats not given RetroMAD1™ (426 days vs 1006 days; P = 0.049). Cats treated with raltegravir and AZT had no significant changes in FeLV viral load over time, but p27 antigen load was decreased from T0 to T3-5 months in cats treated with raltegravir (median p27 antigen level reduced from 50.2% to 42.7%; P = 0.005). All other results were not significantly affected by the treatment provided. Importantly, statistically significant and substantial associations were found between age at FeLV diagnosis and survival time (P = 0.046, R2 = 18.6) and between FeLV viral load at T0 and survival time (P = 0.004, R2 = 44.4). Younger cats, and cats with higher levels of pretreatment FeLV RNA, had reduced survival times. Cats treated with RetroMAD1™ were typically younger (median age 2.0 vs 8.0 years), likely explaining the observed reduction in MST. A significant association was found between FeLV viral load and p27 antigen load at T0 (P = 0.015, R2 = 32.9). CONCLUSIONS: Results from this small case series do not provide convincing support for the use of RetroMAD1™, raltegravir or AZT, alone or in combination, for the treatment of cats progressively infected with FeLV. The changes observed were biologically insignificant. Age and FeLV viral load at diagnosis are useful prognostic markers, and p27 antigen concentration can be used to predict viral load. Larger field trials should be performed examining antiretroviral therapy in FeLV-positive cats with progressive infections, preferably using three or more drugs from at least two classes, as is standard with human antiretroviral therapy. Future studies would be easier in countries with a higher prevalence of FeLV infections than Australia.

Resistance mechanisms in BRAFV600E paediatric high-grade glioma and current therapeutic approaches.

Paediatric high-grade gliomas (pHGG) are aggressive central nervous system tumours with a poor prognosis. BRAFV600E mutant pHGGs can be treated with targeted BRAF inhibitors, which have shown both preclinical activity and potent clinical efficacy. Unfortunately, the development of drug resistance results in disease relapse or progression and is the primary cause of treatment failure. While there is a lot of data to explain mechanisms of resistance in other BRAFV600E tumours, comparatively little is known about the mechanisms of BRAF inhibitor resistance in BRAFV600E pHGG. Recent literature has identified aberrations in members of the RAS/RAF/ERK pathway, the PI3K/AKT/MTOR pathway and the cell cycle as major contributors to the resistance profile. A range of novel therapies have been suggested to overcome BRAF inhibitor drug resistance in BRAFV600E pHGG. This review will discuss the current literature available for BRAF inhibitor resistant BRAFV600E pHGGs and provide an overview of the currently available and proposed therapies.

[SARS-CoV-2 infections in cats, dogs, and other animal species: Findings on infection and data from Switzerland]. / SARS-CoV-2 Infektionen bei Katzen, Hunden und anderen Tieren: Erkenntnisse zur Infektion und Daten aus der Schweiz.

INTRODUCTION: The pandemic with the novel coronavirus (SARS-CoV-2) has led to infections and deaths worldwide. Apart from humans, certain animal species are susceptible to the viral infection. Spillover between humans and animals is favored by close contact; thus, surveillance of animals is an important component to fight the pandemic from a One Health perspective. The Clinical Laboratory of the Vetsuisse Faculty Zurich has been investigating SARS-CoV-2 infections in animals since the beginning of the pandemic. In November 2020, the first SARS-CoV-2 positive Swiss cat was reported to the World Organisation for Animal Health (OIE-WAHIS). The cat showed respiratory signs and lived in a COVID-19 affected household. By now, over 500 natural SARS-CoV-2 infections have been recorded in animals worldwide. A prevalence study on SARS-CoV-2 infections in dogs and cats was carried out together with clinics from Germany and Italy during the first wave of the pandemic (March-July 2020). Among the tested 1137 animals, only one cat and one dog were positive. The prevalence of infection in dogs and cats presented to veterinary clinics was low, even in pandemic hotspot regions. However, recent studies that focused on animals in COVID-19 households found a higher prevalence of infection. A study is currently underway that specifically collects samples from pets from Swiss COVID-19 affected household and collects data on human-animal interaction.

INTRODUCTION: La pandémie à nouveau coronavirus (SARS-CoV-2) a entraîné des infections et des décès dans le monde entier. En dehors de l'homme, certaines espèces animales sont sensibles à cette infection virale. Le passage entre les humains et les animaux est favorisé par un contact étroit, la surveillance des animaux est donc un élément important pour lutter contre la pandémie dans une perspective One Health. Depuis le début de la pandémie, le laboratoire clinique de la faculté Vetsuisse de Zurich étudie les infections par le SRAS-CoV-2 chez les animaux. En novembre 2020, le premier chat suisse positif au SARS-CoV-2 a été signalé à l'Organisation mondiale de la santé animale (OIE-WAHIS). Le chat a montré des signes respiratoires et vivait dans un ménage touché par le COVID-19. À l'heure actuelle, plus de 500 infections naturelles au SRAS-CoV-2 ont été enregistrées chez des animaux dans le monde. Une étude de prévalence sur les infections par le SRAS-CoV-2 chez les chiens et les chats a été réalisée avec des cliniques d'Allemagne et d'Italie pendant la première vague de la pandémie (mars-juillet 2020). Parmi les 1137 animaux testés, seuls un chat et un chien étaient positifs. La prévalence de l'infection chez les chiens et les chats présentés aux cliniques vétérinaires était faible, même dans les régions fortement touchées par la pandémie. Cependant des études récentes, qui se sont concentrées sur les animaux dans les ménages COVID-19, ont révélé une prévalence d'infection plus élevée. Une étude est actuellement en cours qui collecte spécifiquement des échantillons d'animaux de compagnie des ménages suisses touchés par le COVID-19 et enregistre des données sur l'interaction homme-animal.

Collectively stabilizing and orienting posterior migratory forces disperses cell clusters in vivo.

Individual cells detach from cohesive ensembles during development and can inappropriately separate in disease. Although much is known about how cells separate from epithelia, it remains unclear how cells disperse from clusters lacking apical-basal polarity, a hallmark of advanced epithelial cancers. Here, using live imaging of the developmental migration program of Drosophila primordial germ cells (PGCs), we show that cluster dispersal is accomplished by stabilizing and orienting migratory forces. PGCs utilize a G protein coupled receptor (GPCR), Tre1, to guide front-back migratory polarity radially from the cluster toward the endoderm. Posteriorly positioned myosin-dependent contractile forces pull on cell-cell contacts until cells release. Tre1 mutant cells migrate randomly with transient enrichment of the force machinery but fail to separate, indicating a temporal contractile force threshold for detachment. E-cadherin is retained on the cell surface during cell separation and augmenting cell-cell adhesion does not impede detachment. Notably, coordinated migration improves cluster dispersal efficiency by stabilizing cell-cell interfaces and facilitating symmetric pulling. We demonstrate that guidance of inherent migratory forces is sufficient to disperse cell clusters under physiological settings and present a paradigm for how such events could occur across development and disease.

Psychological distress in cervical cancer screening: results from a German online survey.

PURPOSE: The PODCAD study aimed at assessing the degree of psychological stress that women experience due to notification of an abnormal Papanicolaou (Pap) smear finding or a positive human papillomavirus (HPV) test result. METHODS: We designed a survey to address the question of psychological burden due to abnormal Pap smear results and/or positive HPV tests. In this online campaign approach, we aimed to reach > 2000 women all over Germany irrespective of kind and number of abnormal screening findings. We asked for different kinds of anxiety, distress and uncertainty regarding both, Pap and HPV status. RESULTS: A total of 3753 women completed the survey at least partially, and almost 2300 fully completed the survey. Of these, more than 50% were affected already since more than 1 year, and almost half of them had experienced at least three Pap smears in follow-up examinations. Almost 70% of the women were afraid of developing cancer. Intriguingly, almost half of the women with abnormal findings were not aware of their stage of the Pap smear. Furthermore, almost 30% of the women displayed signs of a post-traumatic stress disorder. CONCLUSION: Abnormal results in cervical cancer screening have an impact on patients' psychology, irrespective of the knowledge and severity of the findings. Better information concerning risks and benefits of cervical cancer screening and about the meaning of the outcome of its procedures are required to decrease this anxiety.

The bovine cumulus proteome is influenced by maturation condition and maturational competence of the oocyte.

In vitro maturation (IVM) of oocytes has still a negative impact on the developmental competence of oocytes. Therefore, this study analysed the cumulus proteome of individual cumulus-oocyte complexes (COCs) with and without maturational competence, matured under in vivo or in vitro conditions (n = 5 per group). A novel, ultrasensitive mass spectrometry (MS) based protein profiling approach, using label-free quantification, was applied. The detected cumulus proteome included 2226 quantifiable proteins and was highly influenced by the maturation condition (479 differentially expressed proteins) as well as maturational competence of the corresponding oocyte (424 differentially expressed proteins). Enrichment analysis showed an overrepresentation of the complement and coagulation cascades (CCC), ECM-receptor interaction and steroid biosynthesis in cumulus of COCs that matured successfully under in vivo conditions. Verification of the origin of CCC proteins was achieved through detection of C3 secretion into the maturation medium, with significantly increasing concentrations from 12 (48.4 ng/ml) to 24 hours (68 ng/ml: p < 0.001). In relation, concentrations in follicular fluid, reflecting the in vivo situation, were >100x higher. In summary, this study identified important pathways that are impaired in IVM cumulus, as well as potential markers of the maturational competence of oocytes.

Investigation of the Status Quo of Veterinary Point-of-Care Laboratories in Switzerland: Availability, Application, and Quality Management.

INTRODUCTION: The extent to which Swiss veterinary practitioners follow the guidelines for quality assurance of the American Society for Veterinary Clinical Pathology (ASVCP) for point-of-care (POC) testing is unknown. Thus, the aim of this study was to assess the availability, application, and quality management of POC analyzers in Swiss veterinary practices/clinics. For this purpose, we created an online questionnaire on laboratory equipment, quality management, and biosafety, which all members of the Society of Swiss Veterinarians (GST) were invited to complete. In total, 192 clinics/practices participated, of which 69% had automated POC analyzers, mainly for clinical chemistry (99%) and/or hematology (86%). Sample analyses and equipment maintenance were mostly performed by veterinary technicians (81% and 68%, respectively). Reference intervals were adopted from manufacturers (80%) or literature (17%). The results showed that most participants perform basic internal quality control (chemistry: 75%; hematology: 86%), and many use at least two levels of quality control material (47%-48%). Controls are mostly run once a month (chemistry: 36%; hematology: 35%) or ≤4 times/year (36% and 25%). Only three clinics/practices reported participation in an external quality assessment program; comparative testing was more common (chemistry: 42%; hematology: 52%). Only one-quarter of the participants stated that they make use of the data generated through internal and external quality control measures. In conclusion, POC analyzers are widely available in Swiss veterinary clinics/practices, and internal quality control is performed to some extent. However, quality assessment and management and biosafety awareness and measures need to be improved, ideally with the support of clinical pathologists.

INTRODUCTION: On ignore dans quelle mesure les vétérinaires suisses respectent les directives d'assurance qualité de l'American Society for Veterinary Clinical Pathology (ASVCP) pour les tests au point de service (Point of Care, POC). Ainsi, l'objectif de cette étude était d'évaluer la disponibilité, l'application et la gestion de la qualité des analyseurs POC dans les cabinets/cliniques vétérinaires suisses. À cette fin, nous avons créé un questionnaire en ligne sur les équipements de laboratoire, la gestion de la qualité et la biosécurité que tous les membres de la Société suisse des vétérinaires (GST) ont été invités à remplir. Au total, 192 cliniques/cabinets ont participé, dont 69% avaient des analyseurs POC automatisés, principalement pour la chimie clinique (99%) et/ou l'hématologie (86%). Les analyses des échantillons et la maintenance de l>équipement ont été principalement effectuées par des assistant(e)s en médecine vétérinaires (81% et 68%, respectivement). Les intervalles de référence ont été fixés sur la base des indications des fabricants (80%) ou de la littérature (17%). Les résultats ont montré que la plupart des participants effectuent un contrôle de qualité interne de base (chimie: 75%; hématologie: 86%) et que beaucoup utilisent au moins deux niveaux de matériel de contrôle de la qualité (47% ­48%). Les contrôles sont principalement effectués une fois par mois (chimie: 36%; hématologie: 35%) ou ≤4 fois / an (36% et 25%). Seules trois cliniques/cabinets ont déclaré avoir participé à un programme externe d'évaluation de la qualité. Les tests comparatifs étaient plus courants (chimie: 42%; hématologie: 52%). Un quart seulement des participants ont déclaré utiliser les données générées par des mesures de contrôle de qualité internes et externes. En conclusion, les analyseurs POC sont largement disponibles dans les cliniques/cabinets vétérinaires suisses et le contrôle qualité interne est effectué dans une certaine mesure. Cependant, l'évaluation et la gestion de la qualité ainsi que la sensibilisation et les mesures en matière de biosécurité doivent être améliorées, idéalement avec le soutien de pathologistes cliniciens.

Complex food webs coincide with high genetic potential for chemolithoautotrophy in fractured bedrock groundwater.

Groundwater ecosystems face the challenge of energy limitation due to the absence of light-driven primary production. Lack of space and low oxygen availability might further contribute to generally assumed low food web complexity. Chemolithoautotrophy provides additional input of carbon within the subsurface, however, we still do not understand how abundances of chemolithoautotrophs, differences in surface carbon input, and oxygen availability control subsurface food web complexity. Using a molecular approach, we aimed to disentangle the different levels of potential trophic interactions in oligotrophic groundwater along a hillslope setting of alternating mixed carbonate-/siliciclastic bedrock with contrasting hydrochemical conditions and hotspots of chemolithoautotrophy. Across all sites, groundwater harbored diverse protist communities including Ciliophora, Cercozoa, Centroheliozoa, and Amoebozoa but correlations with hydrochemical parameters were less pronounced for eukaryotes compared to bacteria. Ciliophora-affiliated reads dominated the eukaryotic data sets across all sites. DNA-based evidence for the presence of metazoan top predators such as Cyclopoida (Arthropoda) and Stenostomidae (Platyhelminthes) was only found at wells where abundances of functional genes associated with chemolithoautotrophy were 10-100 times higher compared to wells without indications of these top predators. At wells closer to recharge areas with presumably increased inputs of soil-derived substances and biota, fungi accounted for up to 85% of the metazoan-curated eukaryotic sequence data, together with a low potential for chemolithoautotrophy. Although we did not directly observe higher organisms, our results point to the existence of complex food webs with several trophic levels in oligotrophic groundwater. Chemolithoautotrophy appears to provide strong support to more complex trophic interactions, feeding in additional biomass produced by light-independent CO2-fixation.

Molecular investigations of cat fleas (Ctenocephalides felis) provide the first evidence of Rickettsia felis in Malta and Candidatus Rickettsia senegalensis in Israel.

Rickettsia felis, the causative agent of flea-borne spotted fever, occurs on all continents except Antarctica, owing to the cosmopolitan distribution of its cat flea vector. In this study, cat fleas were collected in two countries where the occurrence of R. felis was either unknown (Malta) or where accurate prevalence data were lacking (Israel). Altogether 129 fleas were molecularly analysed for the presence of rickettsial DNA. On the basis of three genetic markers, R. felis was identified in 39.5% (15/38) of the cat fleas from Malta. Sequences showed 100% identity to each other and to relevant sequences in GenBank. Among the 91 cat fleas from Israel, two (2.2%) contained the DNA of Candidatus Rickettsia senegalensis. Phylogenetically, the R. felis and Candidatus R. senegalensis identified here clustered separately (with high support) but within one clade, which was a sister group to that formed by the typhus group and spotted fever group rickettsiae. This is the first record of R. felis in Malta and of Candidatus R. senegalensis outside its formerly reported geographical range including Africa, Asia and North America.

Evolution of Earth-like Planetary Atmospheres around M Dwarf Stars: Assessing the Atmospheres and Biospheres with a Coupled Atmosphere Biogeochemical Model.

Earth-like planets orbiting M dwarfs are prominent targets when searching for life outside the Solar System. We apply our Coupled Atmosphere Biogeochemical model to investigate the coupling between the biosphere, geosphere, and atmosphere in order to gain insight into the atmospheric evolution of Earth-like planets orbiting M dwarfs and to understand the processes affecting biosignatures and climate on such worlds. This is the first study applying an automated chemical pathway analysis quantifying the production and destruction pathways of molecular oxygen (O2) for an Earth-like planet with an Archean O2 concentration orbiting in the habitable zone of the M dwarf star AD Leonis, which we take as a type-case of an active M dwarf. The main production arises in the upper atmosphere from carbon dioxide photolysis followed by catalytic hydrogen oxide radical (HOx) reactions. The strongest destruction does not take place in the troposphere, as was the case in Gebauer et al. ( 2017 ) for an early Earth analog planet around the Sun, but instead in the middle atmosphere where water photolysis is the strongest. Results further suggest that these atmospheres are in absolute terms less destructive for O2 than for early Earth analog planets around the Sun despite higher concentrations of reduced gases such as molecular hydrogen, methane, and carbon monoxide. Hence smaller amounts of net primary productivity are required to oxygenate the atmosphere due to a change in the atmospheric oxidative capacity, driven by the input stellar spectrum resulting in shifts in the intrafamily HOx partitioning. Under the assumption that an atmosphere of an Earth-like planet survived and evolved during the early high-activity phase of an M dwarf to an Archean-type composition, a possible "Great Oxidation Event," analogous to that on Early Earth, would have occurred earlier in time after the atmospheric composition was reached, assuming the same atmospheric O2 sources and sinks as on early Earth. Key Words: Earth-like-Oxygen-M dwarf stars-Atmosphere-Biogeochemistry-Photochemistry-Biosignatures-Earth-like planets. Astrobiology 18, 856-872.