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1.
bioRxiv ; 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37425679

RESUMO

In the search for natural reservoirs of hepatitis C virus (HCV), a broad diversity of non-human viruses within the Hepacivirus genus has been uncovered. However, the evolutionary dynamics that shaped the diversity and timescale of hepaciviruses evolution remain elusive. To gain further insights into the origins and evolution of this genus, we screened a large dataset of wild mammal samples (n = 1,672) from Africa and Asia, and generated 34 full-length hepacivirus genomes. Phylogenetic analysis of these data together with publicly available genomes emphasizes the importance of rodents as hepacivirus hosts and we identify 13 rodent species and 3 rodent genera (in Cricetidae and Muridae families) as novel hosts of hepaciviruses. Through co-phylogenetic analyses, we demonstrate that hepacivirus diversity has been affected by cross-species transmission events against the backdrop of detectable signal of virus-host co-divergence in the deep evolutionary history. Using a Bayesian phylogenetic multidimensional scaling approach, we explore the extent to which host relatedness and geographic distances have structured present-day hepacivirus diversity. Our results provide evidence for a substantial structuring of mammalian hepacivirus diversity by host as well as geography, with a somewhat more irregular diffusion process in geographic space. Finally, using a mechanistic model that accounts for substitution saturation, we provide the first formal estimates of the timescale of hepacivirus evolution and estimate the origin of the genus to be about 22 million years ago. Our results offer a comprehensive overview of the micro- and macroevolutionary processes that have shaped hepacivirus diversity and enhance our understanding of the long-term evolution of the Hepacivirus genus.

2.
Vet J ; 298-299: 106011, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37336425

RESUMO

Infection with bovine papillomavirus (BPV) types 1 and 2 results in the most common skin tumor of horses, termed equine sarcoid. The persistent and recurrent nature of this tumor stands in contrast to the regressive nature of BPV-1/- 2 induced cutaneous papillomas in cattle. The circulation of horse-specific BPV-1/- 2 variants within equine populations has been suggested as a possible explanation for the difference in clinical presentation of BPV-1/- 2 infection between horses and cattle. In order to investigate this hypothesis, we identified 98 complete BPV-1/- 2 genomes using a Nanopore sequencing approach. Separate BPV-1/- 2 alignments were used to infer Bayesian phylogenetic trees. Phylogeny-trait association concerning host species was investigated using Bayesian Tip-association Significance software (BaTS) Overall, 179 unique BPV-1 and 128 BPV-2 substitutions were found. The E2 coding region in the viral genome exhibited an exceptionally high rate of non-synonymous mutations (81 %, n = 13/16). Interestingly, extensive deletions in the L1/L2 region (up to 1.5 kb) were found exclusively in horse-derived samples. Nevertheless, the most frequently detected single nucleotide polymorphisms were shared between equine and bovine hosts, which is in agreement with BaTS results indicating no phylogeny-host correlation. We found indications that horse-specific mutations might exist in subpopulations of equine derived BPV-1/- 2, but these did not result in horse-adapted genetic variants. Based on these observations, cross-species transmission from cattle to horses seems to be an ongoing process, rather than an ancient occurrence that has been followed by the circulation of horse-adapted BPV variants in the horse population..


Assuntos
Papillomavirus Bovino 1 , Doenças dos Bovinos , Quirópteros , Doenças dos Cavalos , Infecções por Papillomavirus , Neoplasias Cutâneas , Cavalos , Animais , Bovinos , Papillomavirus Bovino 1/genética , Filogenia , Teorema de Bayes , DNA Viral , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/veterinária , Genômica , Infecções por Papillomavirus/veterinária , Doenças dos Cavalos/patologia
4.
Arch Pediatr ; 28(5): 411-416, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34034929

RESUMO

AIM: To evaluate the prognostic significance of initial central nervous system (CNS) involvement of children with acute lymphoblastic leukemia (ALL) enrolled in the EORTC 58951 trial. PATIENTS AND METHODS: From 1998 to 2008, 1930 ALL patients were included in the randomized EORTC 58951 trial. Overall treatment intensity was adjusted according to known prognostic factors including the level of minimal residual disease after induction treatment. CNS-directed therapy comprised four to 11 courses of i.v. methotrexate (5g/m2), and 10 to 19 intrathecal chemotherapy injections, depending on risk group and CNS status. Cranial irradiation was omitted for all patients. RESULTS: The overall 8-year event-free survival (EFS) and overall survival (OS) rates were 81.3% and 88.1%, respectively. In the CNS-1, TPL+, CNS-2, and CNS-3 groups, the 8-year EFS rates were 82.1%, 77.1%, 78.3%, and 57.4%, respectively. Multivariable analysis indicated that initial CNS-3 status, but not CNS-2 or TLP+, was an independent adverse predictor of outcome. The 8-year incidence of isolated CNS relapse was 1.7% and of isolated or combined CNS relapse it was 3.7%. NCI high-risk group, male sex, CNS-2 and CNS-3 status were independent predictors for a higher incidence of any CNS relapse. CONCLUSIONS: CNS-3 status remains associated with poor prognosis and requires intensification of both systemic and CNS-directed therapy. This trial was registered at https://clinicaltrials.gov/under/NCT00003728.


Assuntos
Sistema Nervoso Central/anormalidades , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Valor Preditivo dos Testes , Adolescente , Biomarcadores Tumorais/análise , Sistema Nervoso Central/fisiopatologia , Criança , Pré-Escolar , Irradiação Craniana/tendências , Feminino , Humanos , Lactente , Masculino , Pediatria/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Prognóstico , Resultado do Tratamento
5.
Sci Rep ; 10(1): 21603, 2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-33303796

RESUMO

Previous studies on aesthetic chills (i.e., psychogenic shivers) demonstrate their positive effects on stress, pleasure, and social cognition. We tested whether we could artificially enhance this emotion and its downstream effects by intervening on its somatic markers using wearable technology. We built a device generating cold and vibrotactile sensations down the spine of subjects in temporal conjunction with a chill-eliciting audiovisual stimulus, enhancing the somatosensation of cold underlying aesthetic chills. Results suggest that participants wearing the device experienced significantly more chills, and chills of greater intensity. Further, these subjects reported sharing the feelings expressed in the stimulus to a greater degree, and felt more pleasure during the experience. These preliminary results demonstrate that emotion prosthetics and somatosensory interfaces offer new possibilities of modulating human emotions from the bottom-up (body to mind). Future challenges will include testing the device on a larger sample and diversifying the type of stimuli to account for negatively valenced chills and intercultural differences. Interoceptive technologies offer a new paradigm for affective neuroscience, allowing controlled intervention on conscious feelings and their downstream effects on higher-order cognition.


Assuntos
Calafrios , Estética , Próteses e Implantes , Recompensa , Cognição Social , Dispositivos Eletrônicos Vestíveis , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
6.
Phys Life Rev ; 31: 310-319, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31757602

RESUMO

Historically, multiple theories have posited an active, causal role for perceived bodily states in the creation of human emotion. Recent evidence for embodied cognition, i.e. the role of the entire body in cognition, and support for models positing a key role of bodily homeostasis in the creation of consciousness, i.e. active inference, call for the test of causal rather than correlational links between changes in bodily state and changes in affective state. The controlled stimulation of body signals underlying human emotions and the constant feedback loop between actual and expected sensations during interoceptive processing allows for intervention on higher cognitive functioning. Somatosensory interfaces and emotion prosthesis modulating body perception and human emotions through interoceptive illusions offer new experimental and clinical tools for affective neuroscience. Here, we review challenges in the affective and interoceptive neurosciences, in the light of these novel technologies designed to open avenues for applied research and clinical intervention.


Assuntos
Emoções/fisiologia , Interocepção , Afeto/fisiologia , Humanos , Neurociências
7.
J Eur Acad Dermatol Venereol ; 33(4): 781-785, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30633375

RESUMO

BACKGROUND: Ecthyma gangrenosum (EG) is characterized by the occurrence of erythematous, violaceous or haemorrhagic macules and/or vesicles, often evolving into necrotic ulcers, with a central grey-black eschar. It is a rare skin condition, usually occurring in immunocompromised patients suffering from bacterial sepsis caused by Pseudomonas aeruginosa. However, seemingly healthy children have been diagnosed with this skin disease as well. OBJECTIVES: We report the workup of a case of vulvar EG caused by P. aeruginosa in a toddler, which led to a diagnosis of an underlying neutropenia. Moreover, we provide a brief literature review on those cases of EG where an underlying primary immunodeficiency, neutropenia in particular, was eventually diagnosed. METHODS: A one-and-a-half-year-old girl presented with a history of recurrent (respiratory) infections and the sporadic occurrence of purpuric, vulvar ulcers. Workup consisted of microbiological and haematological investigations, including repeated blood analyses. RESULTS: Bacterial swabs from the vulvar ulcers showed the growth of P. aeruginosa. No concomitant sepsis was present, but laboratory investigations pointed towards a cyclic neutropenia, coinciding with the occurrence of the EG lesions. Topical gentamicin ointment allowed the skin lesions to heal faster. Following the administration of granulocyte colony-stimulating factor (G-CSF), the girl experienced less infections in general and had no recurrence of EG lesions in particular. Treatment with G-CSF could eventually be stopped, and the neutropenia, ultimately transient in nature, completely resolved. CONCLUSION: Children presenting with (anogenital) EG should always alert a physician to consider a potentially underlying immunodeficiency, neutropenia in particular.


Assuntos
Ectima/microbiologia , Gangrena/microbiologia , Neutropenia/tratamento farmacológico , Infecções por Pseudomonas/complicações , Pseudomonas aeruginosa , Doenças da Vulva/microbiologia , Antibacterianos/uso terapêutico , Feminino , Gentamicinas/uso terapêutico , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Humanos , Lactente , Neutropenia/complicações , Infecções por Pseudomonas/tratamento farmacológico
8.
Eur J Clin Microbiol Infect Dis ; 37(1): 135-140, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28986730

RESUMO

The European prototype of hantavirus, Puumala virus (PUUV), isolated from a common wild rodent, the bank vole (Myodes glareolus), causes nephropathia epidemica (NE). NE can perfectly mimic haemolytic-uraemic syndrome (HUS), progressing from an aspecific flu-like syndrome to acute kidney injury with thrombocytopaenia, and presenting with some signs of haemolytic anaemia and/or coagulopathy. Moreover, both NE and HUS can occur in local outbreaks. We report an isolated case of NE, initially referred for plasmapheresis for suspected HUS, although signs of overt haemolysis were lacking. Early suspicion of hantavirus infection, later confirmed by serology and reverse transcription polymerase chain reaction (RT-PCR), prevented subsequent excessive treatment modalities.


Assuntos
Febre Hemorrágica com Síndrome Renal/diagnóstico , Virus Puumala/isolamento & purificação , Doenças dos Roedores/transmissão , Injúria Renal Aguda/virologia , Animais , Arvicolinae/virologia , Diagnóstico Diferencial , Síndrome Hemolítico-Urêmica/diagnóstico , Febre Hemorrágica com Síndrome Renal/terapia , Febre Hemorrágica com Síndrome Renal/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Doenças dos Roedores/virologia , Trombocitopenia/virologia
10.
Epidemiol Infect ; 143(10): 2081-93, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25582980

RESUMO

Two global (re-)emerging zoonoses, leptospirosis and hantavirus infections, are clinically indistinguishable. Thirty-one patients, hospitalized in Sri Lanka for acute severe leptospirosis, were after exclusion of other potentially involved pathogens, prospectively screened with IgM ELISA for both pathogens. Of these, nine (29·0%) were positive for leptospirosis only, one (3·2%) for hantavirus only, seven (22·5%) for both pathogens concomitantly, whereas 13 (41·9%) remained negative for both. Moreover, in a retrospective study of 23 former patients, serologically confirmed for past leptospirosis, six (26·0%) were also positive in two different IgG ELISA hantavirus formats. Surprisingly, European Puumala hantavirus (PUUV) results were constantly higher, although statistically not significantly different, than Asian Hantaan virus (HTNV), suggesting an unexplained cross-reaction, since PUUV is considered absent throughout Asia. Moreover, RT-PCR on all hantavirus IgM ELISA positives was negative. Concomitant leptospirosis-hantavirus infections are probably heavily underestimated worldwide, compromising epidemiological data, therapeutical decisions, and clinical outcome.


Assuntos
Coinfecção/epidemiologia , Infecções por Hantavirus/epidemiologia , Leptospirose/complicações , Leptospirose/epidemiologia , Adolescente , Adulto , Idoso , Anticorpos Antibacterianos/sangue , Anticorpos Antivirais/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Sri Lanka/epidemiologia , Adulto Jovem
11.
Acta Clin Belg ; 70(6): 451-2, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26790559

RESUMO

We present the case of a 17-year-old boy, known with homozygous sickle cell disease, who was admitted because of generalised pain. He developed bilateral periorbital oedema and proptosis, without pain or visual disturbances. In addition to hyperhydration, oxygen and analgesia IV antibiotics were started, to cover a possible osteomyelitis. Patients with sickle cell disease are at risk for vaso-occlusive crises, when the abnormally shaped red blood cells aggregate and block the capillaries. Such a crisis typically presents at a location with high bone marrow activity, as the vertebrae and long bones. At an early age, the bone marrow is still active at other sites, for example the orbital wall, and thus infarction can also occur there. Thus, in young persons with sickle cell disease, it is important to consider orbital wall infarction in the differential diagnosis, since the approach is different from osteomyelitis. If the disease is complicated by an orbital compression syndrome, corticosteroids or surgical intervention may be necessary to preserve the vision. In our patient, an MRI of the orbitae demonstrated periorbital oedema with bone anomalies in the orbital and frontal bones, confirming orbital wall infarction. Ophthalmological examination revealed no signs of pressure on the nervus opticus. The patient recovered gradually with conservative treatment.


Assuntos
Anemia Falciforme/complicações , Infarto/etiologia , Órbita/irrigação sanguínea , Adolescente , Humanos , Masculino
12.
Eur J Clin Microbiol Infect Dis ; 32(10): 1341-5, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23670277

RESUMO

Puumala virus (PUUV) is considered a classic Old World etiologic agent of nephropathia epidemica (NE), or hemorrhagic fever with renal syndrome (HFRS). HFRS is considered to be distinct from hantavirus (cardio-)pulmonary syndrome (HPS or HCPS), described in the New World. Here, we report a severe case, which fulfilled most, if not all, Centers for Disease Control and Prevention (CDC) criteria for HPS, needing non-invasive ventilation and subsequent acute hemodialysis. However, the etiological agent was PUUV, as proved by serological testing, real-time polymerase chain reaction (PCR), and sequencing. Viral antigen was detected by specific anti-PUUV immunostaining, showing, for the first time, greenish intracytoplasmic inclusions in bronchoalveolar lavage (BAL) macrophages. This case definitely confirms that HPS can be encountered during PUUV infections. Interestingly, special findings could render the diagnosis easier, such as greenish homogeneous cytoplasmic inclusions, surrounded by a fine clear halo in BAL macrophages. Therefore, although the diagnosis remains difficult before the onset of renal involvement, the occurrence of severe respiratory failure mimicking community-acquired pneumonia must alert the clinician for possible HPS, especially in endemic areas.


Assuntos
Síndrome Pulmonar por Hantavirus/complicações , Síndrome Pulmonar por Hantavirus/diagnóstico , Febre Hemorrágica com Síndrome Renal/diagnóstico , Corpos de Inclusão Viral , Pulmão/virologia , Macrófagos Alveolares/virologia , Virus Puumala/isolamento & purificação , Adulto , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/virologia , Análise por Conglomerados , Feminino , Humanos , Filogenia , Virus Puumala/classificação , Virus Puumala/genética , Radiografia Torácica , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Sorotipagem , Tomografia Computadorizada por Raios X
13.
Zoonoses Public Health ; 60(7): 461-77, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23176630

RESUMO

Wildlife-originated zoonotic diseases in general are a major contributor to emerging infectious diseases. Hantaviruses more specifically cause thousands of human disease cases annually worldwide, while understanding and predicting human hantavirus epidemics pose numerous unsolved challenges. Nephropathia epidemica (NE) is a human infection caused by Puumala virus, which is naturally carried and shed by bank voles (Myodes glareolus). The objective of this study was to develop a method that allows model-based predicting 3 months ahead of the occurrence of NE epidemics. Two data sets were utilized to develop and test the models. These data sets were concerned with NE cases in Finland and Belgium. In this study, we selected the most relevant inputs from all the available data for use in a dynamic linear regression (DLR) model. The number of NE cases in Finland were modelled using data from 1996 to 2008. The NE cases were predicted based on the time series data of average monthly air temperature (°C) and bank voles' trapping index using a DLR model. The bank voles' trapping index data were interpolated using a related dynamic harmonic regression model (DHR). Here, the DLR and DHR models used time-varying parameters. Both the DHR and DLR models were based on a unified state-space estimation framework. For the Belgium case, no time series of the bank voles' population dynamics were available. Several studies, however, have suggested that the population of bank voles is related to the variation in seed production of beech and oak trees in Northern Europe. Therefore, the NE occurrence pattern in Belgium was predicted based on a DLR model by using remotely sensed phenology parameters of broad-leaved forests, together with the oak and beech seed categories and average monthly air temperature (°C) using data from 2001 to 2009. Our results suggest that even without any knowledge about hantavirus dynamics in the host population, the time variation in NE outbreaks in Finland could be predicted 3 months ahead with a 34% mean relative prediction error (MRPE). This took into account solely the population dynamics of the carrier species (bank voles). The time series analysis also revealed that climate change, as represented by the vegetation index, changes in forest phenology derived from satellite images and directly measured air temperature, may affect the mechanics of NE transmission. NE outbreaks in Belgium were predicted 3 months ahead with a 40% MRPE, based only on the climatological and vegetation data, in this case, without any knowledge of the bank vole's population dynamics. In this research, we demonstrated that NE outbreaks can be predicted using climate and vegetation data or the bank vole's population dynamics, by using dynamic data-based models with time-varying parameters. Such a predictive modelling approach might be used as a step towards the development of new tools for the prevention of future NE outbreaks.


Assuntos
Arvicolinae/crescimento & desenvolvimento , Febre Hemorrágica com Síndrome Renal/veterinária , Virus Puumala/isolamento & purificação , Animais , Arvicolinae/virologia , Bélgica/epidemiologia , Clima , Surtos de Doenças , Fagus/crescimento & desenvolvimento , Finlândia/epidemiologia , Florestas , Febre Hemorrágica com Síndrome Renal/epidemiologia , Febre Hemorrágica com Síndrome Renal/transmissão , Febre Hemorrágica com Síndrome Renal/virologia , Humanos , Modelos Lineares , Modelos Biológicos , Dinâmica Populacional , Quercus/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Temperatura , Zoonoses
14.
Int J Environ Health Res ; 23(2): 132-54, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22894742

RESUMO

Lyme borreliosis (LB) and nephropathia epidemica (NE) are zoonoses resulting from two different transmission mechanisms and the action of two different pathogens: the bacterium Borrelia burgdorferi and the Puumala virus, respectively. The landscape configuration is known to influence the spatial spread of both diseases by affecting vector demography and human exposure to infection. Yet, the connections between landscape and disease have rarely been quantified, thereby hampering the exploitation of land cover data sources to segment areas in function of risk. This study implemented a data-driven approach to relate land cover metrics and an indicator of NE/LB risk at different scales of observation of the landscape. Our results showed the suitability of the modeling approach (r² > 0.75, ρ < 0.001) and highlighted the relevance of the scale of observation in the set of landscape attributes found to influence disease risk as well as common and specific risk factors of NE and LB.


Assuntos
Ecossistema , Febre Hemorrágica com Síndrome Renal/epidemiologia , Doença de Lyme/epidemiologia , Bélgica/epidemiologia , Borrelia burgdorferi , Humanos , Modelos Biológicos , Virus Puumala , Análise de Regressão , Fatores de Risco
16.
Lett Appl Microbiol ; 54(3): 195-202, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22176299

RESUMO

AIMS: The objective was to study the growth of Pseudomonas in a food product (tofu) where it typically occurs as a spoilage organism, and when this product is stored under modified atmosphere. METHODS AND RESULTS: A Pseudomonas strain was isolated from the endogenous microflora of tofu. Tofu was inoculated with the strain, packaged in different gas conditions (air, 100% N(2), 30% CO(2) /70% N(2) or 100% CO(2)) and stored under refrigerated conditions. Microbial loads and the headspace gas composition were monitored during storage. CONCLUSIONS: The strain was capable of growing in atmospheres containing no or limited amounts of oxygen and increased amounts of carbon dioxide. Even when 100% CO(2) was used, growth could not be inhibited completely. SIGNIFICANCE AND IMPACT OF STUDY: in contrast to the general characteristics of the genus Pseudomonas (strictly aerobic, highly sensitive to CO(2)), it should not be expected in the food industry that removing oxygen from the food package and increasing the carbon dioxide content, combined with cold storage, will easily avoid spoilage by Pseudomonas species. Guarantee of hygienic standards and combination of strategies with other microbial growth inhibiting measures should be implemented.


Assuntos
Atmosfera , Microbiologia de Alimentos , Embalagem de Alimentos/métodos , Pseudomonas fluorescens/crescimento & desenvolvimento , Alimentos de Soja/microbiologia , Dióxido de Carbono/análise , Contagem de Colônia Microbiana , Contaminação de Alimentos/prevenção & controle , Nitrogênio/análise , Oxigênio/análise
18.
Clin Microbiol Infect ; 17(6): 947-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21682807

RESUMO

Recently, we proposed a new classification for 'subgenotype A' of hepatitis B virus (HBV), in which the novel 'quasi-subgenotype A3' group comprising HBV 'subgenotype A3', 'tentative A4', and A5 was introduced. Newly 'Tentative subgenotype A7' strains from Cameroon were introduced by Hubschen et al. However, our meticulous phylogenetic analysis demonstrated that these isolates should also be classified into 'quasi-subgenotype A3'. Such misclassification can be avoided by following established principles for HBV subgenotyping. Moreover, their close evolutionary relationship with A3 highlights our hypothesis that geographical origin may be an important factor in further classification of HBV subgenotypes.


Assuntos
Vírus da Hepatite B/classificação , Vírus da Hepatite B/genética , Hepatite B/virologia , Tipagem Molecular , Camarões , Erros de Diagnóstico , Evolução Molecular , Genótipo , Vírus da Hepatite B/isolamento & purificação , Humanos , Tipagem de Sequências Multilocus , Filogenia
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