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1.
Front Oncol ; 12: 1031378, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36582791

RESUMO

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.

2.
Schweiz Arch Tierheilkd ; 163(12): 821-835, 2021 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-34881715

RESUMO

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.


Assuntos
COVID-19 , Doenças do Gato , Doenças do Cão , Animais , COVID-19/veterinária , Doenças do Gato/epidemiologia , Gatos , Doenças do Cão/epidemiologia , Cães , Humanos , Laboratórios Clínicos , SARS-CoV-2 , Suíça/epidemiologia
3.
Nat Commun ; 11(1): 4477, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901019

RESUMO

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.


Assuntos
Drosophila melanogaster/embriologia , Células Germinativas Embrionárias/fisiologia , Animais , Animais Geneticamente Modificados , Fenômenos Biomecânicos , Padronização Corporal/fisiologia , Caderinas/metabolismo , Adesão Celular/fisiologia , Movimento Celular/fisiologia , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/fisiologia , Células Germinativas Embrionárias/citologia , Microscopia de Fluorescência por Excitação Multifotônica , Miosina Tipo II/metabolismo , Transdução de Sinais , Análise de Célula Única , Proteínas rho de Ligação ao GTP/metabolismo
4.
Sci Rep ; 10(1): 9880, 2020 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-32555221

RESUMO

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.


Assuntos
Células do Cúmulo/metabolismo , Proteoma/análise , Animais , Coagulação Sanguínea/genética , Bovinos , Cromatografia Líquida de Alta Pressão , Complemento C3/análise , Complemento C3/metabolismo , Feminino , Líquido Folicular/metabolismo , Técnicas de Maturação in Vitro de Oócitos , Oócitos/crescimento & desenvolvimento , Oócitos/metabolismo , Mapas de Interação de Proteínas/genética , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Espectrometria de Massas em Tandem , Fatores de Tempo
5.
Arch Gynecol Obstet ; 302(3): 699-705, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32594298

RESUMO

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.


Assuntos
Programas de Rastreamento/métodos , Angústia Psicológica , Neoplasias do Colo do Útero/psicologia , Adulto , Feminino , Alemanha , Humanos , Internet , Inquéritos e Questionários , Neoplasias do Colo do Útero/diagnóstico
6.
Schweiz Arch Tierheilkd ; 162(3): 163-173, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32146436

RESUMO

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.


Assuntos
Hospitais Veterinários/estatística & dados numéricos , Laboratórios/estatística & dados numéricos , Laboratórios/normas , Testes Imediatos/estatística & dados numéricos , Animais , Hospitais Veterinários/normas , Testes Imediatos/normas , Suíça
7.
Water Res ; 170: 115306, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31770650

RESUMO

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.


Assuntos
Cadeia Alimentar , Água Subterrânea , Animais , Biota , Crescimento Quimioautotrófico , Ecossistema
8.
Astrobiology ; 18(7): 856-872, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30035637

RESUMO

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.


Assuntos
Atmosfera/análise , Evolução Planetária , Exobiologia/métodos , Astros Celestes , Atmosfera/química , Meio Ambiente Extraterreno/química , Modelos Químicos , Oxigênio/análise , Oxigênio/química
9.
New Microbes New Infect ; 25: 3-6, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29988839

RESUMO

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.

10.
Schweiz Arch Tierheilkd ; 160(2): 95-105, 2018 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-29386166

RESUMO

INTRODUCTION: Feline leukemia virus (FeLV) leads to fatal disease in cats with progressive infection. The aim of this study was to determine the importance of FeLV infection in Switzerland and make a comparison with previous studies. Of 881 blood samples taken from cats living in Switzerland (minimum of 20 samples per Canton), 47 samples were provirus-positive (5.3%; 95% confidence interval (CI) 3.9-7.0%) and 18 samples were antigen-positive (2%; 95% CI 1.2-3.2%). Together with data previously collected in similar studies, these findings demonstrated a decrease in prevalence between 1997 and 2003 followed by a relative constant low prevalence thereafter. Young cats (=2 years) were more frequently infected than older cats, but FeLV-positive cats were up to 15 (antigen-positive) and 19 (provirus-positive) years old. Sexually intact cats were more frequently viremic than neutered cats; purebred cats were somewhat less frequently FeLV-positive than non-purebred cats. In a second study, in which 300 saliva samples were analyzed, samples from 5 cats were FeLV-RNA positive (1.7%; 95% CI, 0.5-3.8%), although one young feral cat had been falsely assumed to be FeLV-negative based on a point-of-care test. Of the 300 cats, only 50% were FeLV tested or vaccinated, although 90% of the cats were at risk of exposure to FeLV. Testing and vaccination of all cats with exposure risk may help further decrease the prevalence of FeLV infection. Moreover, characteristics of FeLV tests should be considered, such as the risk of false negative results in the early phase of infection when performing antigen testing.


INTRODUCTION: Le virus leucémogène félin (FeLV) conduit la plupart du temps à une maladie mortelle chez le chat avec une infection progressive. Le but du présent travail est de mettre en évidence l'importance de l'infection à FeLV en Suisse sur la base de recherches actuelles et de la comparer avec les résultats de recherches antérieures. Afin de répondre à la question de savoir combien de chats présentés à la consultation étaient porteurs du FeLV (positifs au provirus) respectivement excréteurs de FeLV (positifs à l'antigène), on a analysé 881 échantillons sanguins provenant de toute la Suisse (au minimum 20 par canton) : 47 échantillons étaient positifs au provirus (5.3%; 95% intervalle de confiance (CI) 3.9­7.0%) et 18 positifs à l'antigène (2%; 95% CI 1.2­3.2%). Une comparaison avec des recherches semblables faites antérieurement montre que la prévalence du FeLV a diminué entre 1997 et 2003 mais qu'elle stagne depuis lors. Actuellement ce sont plutôt les jeunes chats (=2 ans) qui sont touchés plutôt que les vieux; des chats ont toutefois été trouvés positifs jusqu'à l'âge de 15 ans (positifs à l'antigène) respectivement de 19 ans (positifs au provirus). Les chats non castrés étaient plus souvent virémiques que les castrés et les chats de races étaient aussi, mais un peu moins fréquemment FeLV-positifs. Dans une autre étude suisse, dans laquelle 300 échantillons de salive de chats ont été testés quant à la présence d'ARN-FeLV, 5 chats étaient excréteurs (1.7%; 95% CI 0.5­3.8%). Un jeune chat trouvé, qui avait été testé négatif au test rapide, a été trouvé infecté par le FeLV au moyen de la mise en évidence d'ARN. Sur ces 300 chats, seuls environ 50% avaient été testés quant au FeLV respectivement vaccinés, bien qu'environ 90% aient présenté un risque d'exposition au FeLV. Pour diminuer encore la prévalence du FeLV, il conviendrait de tester et de vacciner tous les chats avec un risque d'exposition au virus. Dans ce contexte, il faut tenir compte des différentes caractéristiques des tests comme la non reconnaissance de la phase d'infection très précoce au moyen du test FeLV rapide.


Assuntos
Vírus da Leucemia Felina/isolamento & purificação , Leucemia Felina/epidemiologia , Infecções por Retroviridae/veterinária , Infecções Tumorais por Vírus/veterinária , Animais , Gatos , Leucemia Felina/virologia , Infecções por Retroviridae/epidemiologia , Infecções por Retroviridae/virologia , Suíça/epidemiologia , Infecções Tumorais por Vírus/epidemiologia , Infecções Tumorais por Vírus/virologia
12.
J Vet Intern Med ; 31(6): 1643-1648, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29024024

RESUMO

BACKGROUND: Thyrotropin (TSH) can be increased in humans with primary hypoadrenocorticism (HA) before glucocorticoid treatment. Increase in TSH is a typical finding of primary hypothyroidism and both diseases can occur concurrently (Schmidt's syndrome); therefore, care must be taken in assessing thyroid function in untreated human patients with HA. OBJECTIVE: Evaluate whether alterations in cTSH can be observed in dogs with HA in absence of primary hypothyroidism. ANIMALS: Thirty dogs with newly diagnosed HA, and 30 dogs in which HA was suspected but excluded based on a normal ACTH stimulation test (controls) were prospectively enrolled. METHODS: cTSH and T4 concentrations were determined in all dogs and at selected time points during treatment (prednisolone, fludrocortisone, or DOCP) in dogs with HA. RESULTS: cTSH concentrations ranged from 0.01 to 2.6 ng/mL (median 0.29) and were increased in 11/30 dogs with HA; values in controls were all within the reference interval (range: 0.01-0.2 ng/dL; median 0.06). There was no difference in T4 between dogs with increased cTSH (T4 range 1.0-2.1; median 1.3 µg/dL) compared to those with normal cTSH (T4 range 0.5-3.4, median 1.4 µg/dL; P=0.69) and controls (T4 range 0.3-3.8, median 1.8 µg/dL; P=0.35). After starting treatment, cTSH normalized after 2-4 weeks in 9 dogs and after 3 and 4 months in 2 without thyroxine supplementation. CONCLUSIONS AND CLINICAL RELEVANCE: Evaluation of thyroid function in untreated dogs with HA can lead to misdiagnosis of hypothyroidism; treatment with glucocorticoids for up to 4 months can be necessary to normalize cTSH.


Assuntos
Doença de Addison/veterinária , Doenças do Cão/diagnóstico , Tireotropina/sangue , Doença de Addison/sangue , Doença de Addison/diagnóstico , Doença de Addison/tratamento farmacológico , Animais , Desoxicorticosterona/análogos & derivados , Desoxicorticosterona/uso terapêutico , Doenças do Cão/sangue , Doenças do Cão/tratamento farmacológico , Cães , Feminino , Glucocorticoides/uso terapêutico , Hipotireoidismo/veterinária , Masculino , Prednisolona/uso terapêutico , Tiroxina/sangue
13.
Astrobiology ; 17(1): 27-54, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28103105

RESUMO

Understanding the evolution of Earth and potentially habitable Earth-like worlds is essential to fathom our origin in the Universe. The search for Earth-like planets in the habitable zone and investigation of their atmospheres with climate and photochemical models is a central focus in exoplanetary science. Taking the evolution of Earth as a reference for Earth-like planets, a central scientific goal is to understand what the interactions were between atmosphere, geology, and biology on early Earth. The Great Oxidation Event in Earth's history was certainly caused by their interplay, but the origin and controlling processes of this occurrence are not well understood, the study of which will require interdisciplinary, coupled models. In this work, we present results from our newly developed Coupled Atmosphere Biogeochemistry model in which atmospheric O2 concentrations are fixed to values inferred by geological evidence. Applying a unique tool (Pathway Analysis Program), ours is the first quantitative analysis of catalytic cycles that governed O2 in early Earth's atmosphere near the Great Oxidation Event. Complicated oxidation pathways play a key role in destroying O2, whereas in the upper atmosphere, most O2 is formed abiotically via CO2 photolysis. The O2 bistability found by Goldblatt et al. ( 2006 ) is not observed in our calculations likely due to our detailed CH4 oxidation scheme. We calculate increased CH4 with increasing O2 during the Great Oxidation Event. For a given atmospheric surface flux, different atmospheric states are possible; however, the net primary productivity of the biosphere that produces O2 is unique. Mixing, CH4 fluxes, ocean solubility, and mantle/crust properties strongly affect net primary productivity and surface O2 fluxes. Regarding exoplanets, different "states" of O2 could exist for similar biomass output. Strong geological activity could lead to false negatives for life (since our analysis suggests that reducing gases remove O2 that masks its biosphere over a wide range of conditions). Key Words: Early Earth-Proterozoic-Archean-Oxygen-Atmosphere-Biogeochemistry-Photochemistry-Biosignatures-Earth-like planets. Astrobiology 16, 27-54.


Assuntos
Atmosfera , Planeta Terra , Evolução Planetária , Exobiologia , Meio Ambiente Extraterreno , Modelos Teóricos , Altitude , Dióxido de Carbono/análise , Metano/análise , Óxido Nitroso/análise , Ozônio/química , Reprodutibilidade dos Testes , Propriedades de Superfície , Temperatura , Água/química
14.
Pharmacogenomics J ; 17(1): 69-75, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-26644205

RESUMO

Metabolic syndrome after transplantation is a major concern following solid organ transplantation (SOT). The CREB-regulated transcription co-activator 2 (CRTC2) regulates glucose metabolism. The effect of CRTC2 polymorphisms on new-onset diabetes after transplantation (NODAT) was investigated in a discovery sample of SOT recipients (n1=197). Positive results were tested for replication in two samples from the Swiss Transplant Cohort Study (STCS, n2=1294 and n3=759). Obesity and other metabolic traits were also tested. Associations with metabolic traits in population-based samples (n4=46'186, n5=123'865, n6>100,000) were finally analyzed. In the discovery sample, CRTC2 rs8450-AA genotype was associated with NODAT, fasting blood glucose and body mass index (Pcorrected<0.05). CRTC2 rs8450-AA genotype was associated with NODAT in the second STCS replication sample (odd ratio (OR)=2.01, P=0.04). In the combined STCS replication samples, the effect of rs8450-AA genotype on NODAT was observed in patients having received SOT from a deceased donor and treated with tacrolimus (n=395, OR=2.08, P=0.02) and in non-kidney transplant recipients (OR=2.09, P=0.02). Moreover, rs8450-AA genotype was associated with overweight or obesity (n=1215, OR=1.56, P=0.02), new-onset hyperlipidemia (n=1007, OR=1.76, P=0.007), and lower high-density lipoprotein-cholesterol (n=1214, ß=-0.08, P=0.001). In the population-based samples, a proxy of rs8450G>A was significantly associated with several metabolic abnormalities. CRTC2 rs8450G>A appears to have an important role in the high prevalence of metabolic traits observed in patients with SOT. A weak association with metabolic traits was also observed in the population-based samples.


Assuntos
Síndrome Metabólica/epidemiologia , Síndrome Metabólica/genética , Transplante de Órgãos/efeitos adversos , Polimorfismo de Nucleotídeo Único , Fatores de Transcrição/genética , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/genética , Dislipidemias/epidemiologia , Dislipidemias/genética , Frequência do Gene , Predisposição Genética para Doença , Heterozigoto , Homozigoto , Humanos , Incidência , Modelos Lineares , Modelos Logísticos , Síndrome Metabólica/diagnóstico , Análise Multivariada , Obesidade/epidemiologia , Obesidade/genética , Razão de Chances , Fenótipo , Prevalência , Medição de Risco , Fatores de Risco , Suíça/epidemiologia , Fatores de Tempo , Resultado do Tratamento
15.
J Tissue Eng Regen Med ; 11(1): 109-120, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-24737702

RESUMO

Previously we demonstrated the superiority of small islets vs large islets in terms of function and survival after transplantation, and we generated reaggregated rat islets (pseudo-islets) of standardized small dimensions by the hanging-drop culture method (HDCM). The aim of this study was to generate human pseudo-islets by HDCM and to evaluate and compare the physiological properties of rat and human pseudo-islets. Isolated rat and human islets were dissociated into single cells and incubated for 6-14 days by HDCM. Newly formed pseudo-islets were analysed for dimensions, morphology, glucose-stimulated insulin secretion (GSIS) and total insulin content. The morphology of reaggregated human islets was similar to that of native islets, while rat pseudo-islets had a reduced content of α and δ cells. GSIS of small rat and human pseudo-islets (250 cells) was increased up to 4.0-fold (p < 0.01) and 2.5-fold (p < 0.001), respectively, when compared to their native counterparts. Human pseudo-islets showed a more pronounced first-phase insulin secretion as compared to intact islets. GSIS was inversely correlated to islet size, and small islets (250 cells) contained up to six-fold more insulin/cell than large islets (1500 cells). Tissue loss with this new technology could be reduced to 49.2 ± 1.5% in rat islets, as compared to the starting amount. With HDCM, pseudo-islets of standardized size with similar cellular composition and improved biological function can be generated, which compensates for tissue loss during production. Transplantation of small pseudo-islets may represent an attractive strategy to improve graft survival and function, due to better oxygen and nutrient supply during the phase of revascularization. Copyright © 2014 John Wiley & Sons, Ltd.


Assuntos
Técnicas de Cultura de Células/métodos , Insulina/química , Ilhotas Pancreáticas/citologia , Animais , Agregação Celular , Células Cultivadas , Glucose/química , Sobrevivência de Enxerto , Gravitação , Humanos , Células Secretoras de Insulina/citologia , Masculino , Oxigênio/química , Perfusão , Ratos , Ratos Endogâmicos Lew
16.
Schweiz Arch Tierheilkd ; 158(10): 691-700, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27707682

RESUMO

INTRODUCTION: 'Candidatus Neoehrlichia mikurensis' is an emerging tick-borne zoonotic agent that primarily affects immunocompromised human patients. Dogs and foxes are frequently exposed to ticks, and both species are in close proximity to humans. This is the first study to systematically investigate the occurrence of 'Candidatus Neoehrlichia mikurensis' in Canidae in Europa. We analyzed 1'739 blood samples from dogs in Switzerland, Italy, Spain and Portugal and 162 blood samples from free-ranging red foxes (Vulpes vulpes) in Switzerland. All samples were tested using a previously described multiplex real-time PCR for the Anaplasmataceae family, the 'Candidatus Neoehrlichia' genus and the 'Candidatus Neoehrlichia mikurensis' species. All Anaplasmataceae positive samples were subsequently tested using specific real-time PCRs for Anaplasma phagocytophilum, Anaplasma platys, Ehrlichia canis and Rickettsia helvetica. Among the tested animals, one dog from Zurich tested positive for 'Candidatus Neoehrlichia mikurensis'. The 12-year old West Highland white terrier had been splenectomized 3 months prior to the blood collection and presented with polyuria/polydipsia. Fanconi syndrome was diagnosed based on glucosuria with normoglycemia and hyperaminoaciduria. A. platys and E. canis were detected in 14/249 dogs from Sicily and Portugal; two of the dogs were coinfected with both agents. Four Swiss foxes tested positive for A. phagocytophilium. R. helvetica was detected for the first time in a red fox. In conclusion, 'Candidatus Neoehrlichia mikurensis' infection should be considered in sick dogs, particularly when immunocompromised. The pathogen seems not to be widespread in Canidae in the investigated countries. Conversely, other Anaplasmataceae were more readily detected in dogs and foxes.


INTRODUCTION: 'Candidatus Neoehrlichia mikurensis' est un agent de zoonose transmis par les tiques qui gagne en importance et concerne principalement les patients immunosupprimés. Les chiens comme les renards sont souvent concernés par des morsures de tiques et vivent en contact étroit avec les êtres humains. Dans le présent travail, nous étudions pour la première fois systématiquement la présence de 'Candidatus Neoehrlichia mikurensis' chez les canidés en Europe. Les échantillons sanguins analysés provenaient de 1'739 chiens de Suisse, d'Italie, d'Espagne et du Portugal ainsi que de 162 renards (Vulpes vulpes) de Suisse. Tous les échantillons ont été examinés avec un test de PCR multiplex en temps réel déjà publié quant à la présence d'agents de la famille des Anaplasmataceae, du genre 'Candidatus Neoehrlichia' et de l'espèce 'Candidatus Neoehrlichia mikurensis'. Les échantillons positifs aux Anaplasmataceae ont ensuite été testés avec un test PCR en temps réel spécifique quant à Anaplasma phagocytophilum, Anaplasma platys, Ehrlichia canis und Rickettsia helvetica. Parmi les échantillons examinés se trouvait celui d'un chien de Zürich qui était infecté par 'Candidatus Neoehrlichia mikurensis'. Ce West Highland White Terrier de 12 ans avait été présenté pour polyurie/polydipsie; il avait été splénectomisé trois mois avant la prise de l'échantillon. Au vu d'une glycosurie et d'une hyperaminoacidurie accompagnées d'une glycémie normale, on a posé le diagnostic de syndrome de Fanconi. A. platys et E. canis ont été mis en évidence chez 14/249 chiens provenant de Sicile et du Portugal; deux chiens étaient infectés par les deux agents pathogènes. Quatre renards suisses étaient positifs à A. phagocytophilium et R. helvetica a été trouvé pour la première fois chez un renard. En résumé, on peut dire qu'une infection à 'Candidatus Neoehrlichia mikurensis' chez un chien malade doit être prise en considération comme diagnostic différentiel, particulièrement chez les anomaux immunosupprimés. Toutefois cet agent n'est pas très répandu chez les canidés des pays examinés, contrairement aux autres Anaplasmataceae spp. qui ont été trouvées plus souvent chez les chiens et les renards.


Assuntos
Infecções por Anaplasmataceae/veterinária , Doenças do Cão/diagnóstico , Doenças do Cão/epidemiologia , Infecções por Rickettsiaceae/veterinária , Zoonoses/diagnóstico , Zoonoses/epidemiologia , Anaplasmataceae/isolamento & purificação , Infecções por Anaplasmataceae/diagnóstico , Infecções por Anaplasmataceae/epidemiologia , Infecções por Anaplasmataceae/microbiologia , Animais , Coinfecção , Doenças do Cão/microbiologia , Cães , Raposas/microbiologia , Genes Bacterianos/genética , Região do Mediterrâneo , Reação em Cadeia da Polimerase/veterinária , Prevalência , Rickettsiaceae/isolamento & purificação , Infecções por Rickettsiaceae/epidemiologia , Infecções por Rickettsiaceae/microbiologia , Suíça , Zoonoses/microbiologia
17.
J Clin Endocrinol Metab ; 101(12): 5044-5052, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27648961

RESUMO

BACKGROUND: Plasma acylcarnitine levels are elevated by physiological conditions such as fasting and exercise but also in states of insulin resistance and obesity. AIM: To elucidate the contribution of liver and skeletal muscle to plasma acylcarnitines in the fasting state and during exercise in humans. METHODS: In 2 independent studies, young healthy males were fasted overnight and performed an acute bout of exercise to investigate either acylcarnitines in skeletal muscle biopsies and arterial-to-venous plasma differences over the exercising and resting leg (n = 9) or the flux over the hepato-splanchnic bed (n = 10). RESULTS: In the fasting state, a pronounced release of C2- and C3-carnitines from the hepato-splanchnic bed and an uptake of free carnitine by the legs were detected. Exercise further increased the release of C3-carnitine from the hepato-splanchnic bed and the uptake of free carnitine in the exercising leg. In plasma and in the exercising muscle, exercise induced an increase of most acylcarnitines followed by a rapid decline to preexercise values during recovery. In contrast, free carnitine was decreased in the exercising muscle and quickly restored thereafter. C8-, C10-, C10:1-, C12-, and C12:1-carnitines were released from the exercising leg and simultaneously; C6, C8, C10, C10:1, C14, and C16:1 were taken up by the hepato-splanchnic. CONCLUSION: These data provide novel insight to the organo-specific release/uptake of acylcarnitines. The liver is a major contributor to systemic short chain acylcarnitines, whereas the muscle tissue releases mostly medium chain acylcarnitines during exercise, indicating that other tissues are contributing to the systemic increase in long chain acylcarnitines.


Assuntos
Carnitina/análogos & derivados , Exercício Físico/fisiologia , Jejum/metabolismo , Fígado/metabolismo , Músculo Esquelético/metabolismo , Adulto , Carnitina/sangue , Carnitina/metabolismo , Jejum/sangue , Humanos , Perna (Membro) , Masculino , Adulto Jovem
18.
Insect Mol Biol ; 25(3): 202-15, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26778648

RESUMO

Lysozymes are enzymes that destroy bacterial cell walls by hydrolysing the polysaccharide component of peptidoglycan. In insects, there are two classes of lysozymes, the c-type with muramidase activity and the i-type whose prototypical members from annelids and molluscs possess both muramidase and isopeptidase activities. Many insect genes encoding c-type and i-type lysozymes have been identified during genome and transcriptome analyses, but only c-type lysozymes have been functionally characterized at the protein level. Here we produced one of five i-type lysozymes represented in the immunity-related transcriptome of the invasive harlequin ladybird beetle Harmonia axyridis as recombinant protein. This was the only one containing the serine and histidine residues that are thought to be required for isopeptidase activity. This i-type lysozyme was recombinantly expressed in the yeast Pichia pastoris, but the purified protein was inactive in both muramidase and isopeptidase assays. Transcription and immunofluorescence analysis revealed that this i-type lysozyme is produced in the fat body but is not inducible by immune challenge. These data suggest that i-type lysozymes in insects may have acquired novel and as yet undetermined functions in the course of evolution.


Assuntos
Besouros/enzimologia , Muramidase/metabolismo , Sequência de Aminoácidos , Animais , Carbono-Nitrogênio Liases/análise , Besouros/genética , Besouros/imunologia , Imunidade Inata , Dados de Sequência Molecular , Muramidase/genética , Pichia
19.
J Vet Intern Med ; 30(1): 174-82, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26727465

RESUMO

BACKGROUND: Canine babesiosis, caused by Babesia canis, is a prevalent and clinically relevant disease in Europe. Severe acute babesiosis is characterized by a high mortality but prognosis is not always correlated with clinical signs nor with the level of parasitemia. OBJECTIVE: This study evaluated prognostic markers associated with poor outcomes in acute Babesia canis infections. ANIMALS AND METHODS: We compared the results of routine laboratory profiles, hand-held lactate and glucose analyzer, and the acute phase response in 2 groups of naturally infected dogs (7 survivors and 8 nonsurvivors). Samples were collected at the time of first admission and before any treatment. Subsequently, the course of prognostic markers was followed in 3 dogs experimentally inoculated with B. canis. RESULTS: Nonsurvivors showed significantly higher concentrations of lactate, triglycerides and phosphate and lower hematocrit, leukocyte counts, total serum protein concentrations, and thrombocyte counts when compared to survivors. All nonsurvivors (8/8) had hyperlactatemia, whereas most survivors (6/7) had values within the reference range. All survivors had leucocyte counts within the reference range, unlike the nonsurvivors, which showed leukopenia. During the course of acute babesiosis, the variables serum lactate, triglyceride, and phosphate concentrations, and thrombocyte count only exceeded a prognostic threshold during acute crisis. CONCLUSIONS AND CLINICAL IMPORTANCE: Poor outcome in acute B. canis infection is indicated by changes in the laboratory profile. Intensive care should be considered for dogs presenting with moderate anemia, severe thrombocytopenia, mild to moderate leukopenia, hyperlactatemia, moderately increased serum phosphate, and triglyceride concentrations, and moderately decreased total serum protein concentrations.


Assuntos
Babesia/classificação , Babesiose/parasitologia , Doenças do Cão/parasitologia , Animais , Antiprotozoários/uso terapêutico , Babesiose/sangue , Babesiose/tratamento farmacológico , Biomarcadores , Doenças do Cão/sangue , Doenças do Cão/tratamento farmacológico , Cães , Feminino , Masculino , Prognóstico , Resultado do Tratamento
20.
J Lab Autom ; 21(3): 439-50, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26259574

RESUMO

Automated cell cultivation is an important tool for simplifying routine laboratory work. Automated methods are independent of skill levels and daily constitution of laboratory staff in combination with a constant quality and performance of the methods. The Biomek Cell Workstation was configured as a flexible and compatible system. The modified Biomek Cell Workstation enables the cultivation of adherent and suspension cells. Until now, no commercially available systems enabled the automated handling of both types of cells in one system. In particular, the automated cultivation of suspension cells in this form has not been published. The cell counts and viabilities were nonsignificantly decreased for cells cultivated in AutoFlasks in automated handling. The proliferation of manual and automated bioscreening by the WST-1 assay showed a nonsignificant lower proliferation of automatically disseminated cells associated with a mostly lower standard error. The disseminated suspension cell lines showed different pronounced proliferations in descending order, starting with Jurkat cells followed by SEM, Molt4, and RS4 cells having the lowest proliferation. In this respect, we successfully disseminated and screened suspension cells in an automated way. The automated cultivation and dissemination of a variety of suspension cells can replace the manual method.


Assuntos
Automação Laboratorial/métodos , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Contagem de Células , Linhagem Celular , Proliferação de Células , Sobrevivência Celular , Humanos
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