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1.
Ticks Tick Borne Dis ; 15(4): 102350, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38723399

RESUMO

Wild animals in general, birds in particular, play a key role in transporting ticks and propagating tick-borne pathogens. Several studies have confirmed the infection of birds with Anaplasma phagocytophilum, with overall prevalence varying widely from country to country and/or study to study. This zoonotic bacterium, transmitted mainly by ticks of the genus Ixodes, is responsible for granulocytic anaplasmosis in humans (HGA) and domestic animals (cats, dogs, horses). The disease is also called tick-borne fever (TBF) in ruminants. Extremely rare in the USA, TBF is very common in Europe, where it causes economic losses in livestock. Conversely, HGA is well established in the USA whereas only a few less severe cases have been observed in Europe. Current typing techniques support the existence of multiple variants with differences in virulence/pathogenicity and tropism for certain tick and host species. However, epidemiological cycles remain difficult to characterize in Europe. Several studies describe a cycle apparently involving only birds in Europe, but no such study has been conducted in mainland France. Our objectives were to search for A. phagocytophilum in passerine birds in the Ile-de-France region and to explore their diversity using groEL and ankA gene typing and multilocus sequence typing (MLST). Various tissues (spleen, liver, and skin) were collected from cadavers of 680 passerines between March and December 2021. The presence of A. phagocytophilum was detected by qPCR Taqman targeting the msp2 gene. Three blackbirds (Turdus merula) were found positive, representing detection rates of 0.4 % in all birds tested and 3.3 % in blackbirds. The higher frequency of detection in blackbirds could be at least partially explained by their lifestyle, as they feed on the ground. Analysis of the results of groEL and ankA typing and MLST from positive blackbirds support the hypothesis that the avian A. phagocytophilum strains in Ile-de-France are distinct from those found in mammals, and that they form their own cluster in Europe.


Assuntos
Anaplasma phagocytophilum , Doenças das Aves , Ehrlichiose , Animais , Anaplasma phagocytophilum/isolamento & purificação , Anaplasma phagocytophilum/genética , Doenças das Aves/epidemiologia , Doenças das Aves/microbiologia , Ehrlichiose/epidemiologia , Ehrlichiose/veterinária , Ehrlichiose/microbiologia , Passeriformes , Filogenia , França/epidemiologia , Prevalência
2.
Vet Parasitol ; 328: 110190, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38714064

RESUMO

In Europe, tick-borne diseases (TBDs) cause significant morbidity and mortality, affecting both human and animal health. Ticks can transmit a wide variety of pathogens (bacteria, viruses, and parasites) and feed on many vertebrate hosts. The incidence and public health burden of TBDs are tending to intensify in Europe due to various factors, mainly anthropogenic and often combined. Early detection of tick-borne pathogens (TBPs), preventive measures and treatment are of great importance to control TBDs and their expansion. However, there are various limitations in terms of the sensitivity and/or specificity of detection and prevention methods, and even in terms of feasibility. Aptamers are single-stranded DNA or RNA that could address these issues as they are able to bind with high affinity and specificity to a wide range of targets (e.g., proteins, small compounds, and cells) due to their unique three-dimensional structure. To date, aptamers have been selected against TBPs such as tick-borne encephalitis virus, Francisella tularensis, and Rickettsia typhi. These studies have demonstrated the benefits of aptamer-based assays for pathogen detection and medical diagnosis. In this review, we address the applications of aptamers to TBDs and discuss their potential for improving prevention measures (use of chemical acaricides, vaccination), diagnosis and therapeutic strategies to control TBDs.


Assuntos
Aptâmeros de Nucleotídeos , Doenças Transmitidas por Carrapatos , Doenças Transmitidas por Carrapatos/prevenção & controle , Doenças Transmitidas por Carrapatos/epidemiologia , Animais , Humanos , Europa (Continente)/epidemiologia , Carrapatos/microbiologia , Carrapatos/virologia , Controle de Ácaros e Carrapatos/métodos
3.
Sci Rep ; 14(1): 2465, 2024 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291133

RESUMO

A. phagocytophilum is a zoonotic and tick-borne bacterium, threatening human and animal health. Many questions persist concerning the variability of strains and the mechanisms governing the interactions with its different hosts. These gaps can be explained by the difficulty to cultivate and study A. phagocytophilum because of its strict intracellular location and the lack of specific tools, in particular monoclonal antibodies, currently unavailable. The objective of our study was to develop DNA aptamers against A. phagocytophilum, or molecules expressed during the infection, as new study and/or capture tools. Selecting aptamers was a major challenge due to the strict intracellular location of the bacterium. To meet this challenge, we set up a customized selection protocol against an enriched suspension of A. phagocytophilum NY18 strain, cultivated in HL-60 cells. The implementation of SELEX allowed the selection of three aptamers, characterized by a high affinity for HL-60 cells infected with A. phagocytophilum NY18 strain. Interestingly, the targets of these three aptamers are most likely proteins expressed at different times of infection. The selected aptamers could contribute to increase our understanding of the interactions between A. phagocytophilum and its hosts, as well as permit the development of new diagnostic, therapeutic or drug delivery appliances.


Assuntos
Anaplasma phagocytophilum , Carrapatos , Animais , Humanos , Anaplasma phagocytophilum/genética , Extratos Celulares , Carrapatos/microbiologia , Células HL-60
4.
J Clin Sleep Med ; 19(8): 1533-1544, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37078190

RESUMO

STUDY OBJECTIVES: Sleep disturbances are an underrecognized public health issue that results in various adverse outcomes and disturbed quality of life. Blood pressure variability (BPV) is an emerging entity in assessing cardiovascular disease risk and accumulating evidence suggests that BPV is closely associated with end-organ damage. This review aims to explore the association between sleep disturbances and BPV. METHODS: A comprehensive systematic literature search was conducted electronically using Web of Science, Ovid MEDLINE, , and SCOPUS. The electronic search was restricted to relevant English-language studies published between 1985 and August 2020. Most studies were prospective cohorts in design. After applying eligibility criteria, 29 articles were included for synthesis. RESULTS: This review shows that sleep disturbances are linked to short-term, midterm, and long-term BPV. Restless legs syndrome, shift work, insomnia, short sleep, long sleep, obstructive sleep apnea, and sleep deprivation were all positively associated with systolic blood pressure or diastolic blood pressure fluctuations. CONCLUSIONS: Given the prognostic implications of BPV and sleep disturbances on cardiovascular mortality, recognizing and treating both disorders is essential. More research is needed to examine the impact of sleep disorder treatment on BPV and cardiovascular mortality. CITATION: Al Haddad N, Costanian C, Zibara V, et al. The association between sleep disturbances and blood pressure variability: a review of the literature. J Clin Sleep Med. 2023;19(8):1533-1544.


Assuntos
Doenças Cardiovasculares , Transtornos do Sono-Vigília , Humanos , Pressão Sanguínea/fisiologia , Estudos Prospectivos , Qualidade de Vida , Transtornos do Sono-Vigília/complicações , Transtornos do Sono-Vigília/epidemiologia , Privação do Sono
5.
Pathogens ; 12(3)2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36986304

RESUMO

The COVID-19 pandemic due to the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has been plaguing the world since late 2019/early 2020 and has changed the way we function as a society, halting both economic and social activities worldwide. Classrooms, offices, restaurants, public transport, and other enclosed spaces that typically gather large groups of people indoors, and are considered focal points for the spread of the virus. For society to be able to go "back to normal", it is crucial to keep these places open and functioning. An understanding of the transmission modes occurring in these contexts is essential to set up effective infection control strategies. This understanding was made using a systematic review, according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses statement (PRISMA) 2020 guidelines. We analyze the different parameters influencing airborne transmission indoors, the mathematical models proposed to understand it, and discuss how we can act on these parameters. Methods to judge infection risks through the analysis of the indoor air quality are described. Various mitigation measures are listed, and their efficiency, feasibility, and acceptability are ranked by a panel of experts in the field. Thus, effective ventilation procedures controlled by CO2-monitoring, continued mask wearing, and a strategic control of room occupancy, among other measures, are put forth to enable a safe return to these essential places.

6.
Viruses ; 15(3)2023 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-36992499

RESUMO

Tick-borne encephalitis (TBE) is a viral disease endemic in Eurasia. The virus is mainly transmitted to humans via ticks and occasionally via the consumption of unpasteurized milk products. The European Centre for Disease Prevention and Control reported an increase in TBE incidence over the past years in Europe as well as the emergence of the disease in new areas. To better understand this phenomenon, we investigated the drivers of TBE emergence and increase in incidence in humans through an expert knowledge elicitation. We listed 59 possible drivers grouped in eight domains and elicited forty European experts to: (i) allocate a score per driver, (ii) weight this score within each domain, and (iii) weight the different domains and attribute an uncertainty level per domain. An overall weighted score per driver was calculated, and drivers with comparable scores were grouped into three terminal nodes using a regression tree analysis. The drivers with the highest scores were: (i) changes in human behavior/activities; (ii) changes in eating habits or consumer demand; (iii) changes in the landscape; (iv) influence of humidity on the survival and transmission of the pathogen; (v) difficulty to control reservoir(s) and/or vector(s); (vi) influence of temperature on virus survival and transmission; (vii) number of wildlife compartments/groups acting as reservoirs or amplifying hosts; (viii) increase of autochthonous wild mammals; and (ix) number of tick species vectors and their distribution. Our results support researchers in prioritizing studies targeting the most relevant drivers of emergence and increasing TBE incidence.


Assuntos
Dermacentor , Encefalite Transmitida por Carrapatos , Ixodes , Animais , Humanos , Europa (Continente)/epidemiologia , Animais Selvagens , Mamíferos
7.
Microb Risk Anal ; 22: 100237, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36320929

RESUMO

Monkeypox (MPX) is a zoonotic infectious disease caused by Monkeypox virus (MPXV), an enveloped DNA virus belonging to the Poxviridae family and the Orthopoxvirus genus. Since early May 2022, a growing number of human cases of Monkeypox have been reported in non-endemic countries, with no history of contact with animals imported from endemic and enzootic areas, or travel to an area where the virus usually circulated before May 2022. This qualitative risk assessment aimed to investigate the probability that MPXV transmission occurs through food during its handling and consumption. The risk assessment used "top-down" (based on epidemiological data) and "bottom-up" (following the agent through the food chain to assess the risk of foodborne transmission to human) approaches, which were combined. The "top-down" approach first concluded that bushmeat was the only food suspected as a source of contamination in recorded cases of MPXV, by contact or ingestion. The "bottom-up" approach then evaluated the chain of events required for a human to become ill after handling or consuming food. This approach involves several conditions: (i) the food must be contaminated with MPXV (naturally, by an infected handler or after contact with a contaminated surface); (ii) the food must contain viable virus when it reaches the handler or consumer; (iii) the person must be exposed to the virus and; (iv) the person must be infected after exposure. Throughout the risk assessment, some data gaps were identified and highlighted. The conclusions of the top-down and bottom-up approaches are consistent and suggest that the risk of transmission of MPXV through food is hypothetical and that such an occurrence was never reported. In case of contamination, cooking (e.g., 12 min at 70°C) could be considered effective in inactivating Poxviridae in foods. Recommendations for risk management are proposed. To our knowledge, this is the first risk assessment performed on foodborne transmission of MPXV.

8.
Methods Protoc ; 5(6)2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36412811

RESUMO

The high failure rate of the in vitro aptamer selection process by SELEX (Systematic Evolution of Ligands by EXponential enrichment) limits the production of these innovative oligonucleotides and, consequently, limits their potential applications. The generation of single-stranded DNA (ssDNA) is a critical step of SELEX, directly affecting the enrichment and the selection of potential binding sequences. The main goal of this study was to confirm the best method for generating ssDNA by comparing the purification of ssDNA, using streptavidin-coated beads, and lambda exonuclease digestion, and by improving ssDNA recovery through protocol improvements. In addition, three techniques for quantifying the ssDNA generated (Qubit vs. NanodropTM vs. gel quantification) were compared, and these demonstrated the accuracy of the gel-based quantification method. Lambda exonuclease digestion was found to be more efficient for ssDNA recovery than purification using streptavidin-coated beads, both quantitatively and qualitatively. In conclusion, this work provides a detailed and rigorous protocol for generating ssDNA, improving the chances of a successful aptamer selection process.

9.
Infect Dis Now ; 52(5): 294-298, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35753629

RESUMO

The Monkeypox virus belongs to the Orthopoxvius genus, as does the specifically human smallpox virus. It is zoonotic and had never previously been considered as capable of human-to-human transmission over more than nine viral generation cycles. While relevant animal reservoirs have yet to be identified, non-human primates (NHP) are only accidental hosts. The potentially high number of current human shedders during the clinical phase (3 weeks maximum) raises the question of a risk in our countries of animals being contaminated by infected humans (reverse zoonosis). Cats as well as cows are susceptible to the Cowpox virus, another zoonotic Orthopoxvirus, which they transmit to humans. Dogs are much less susceptible to this virus and seem only receptive to Vaccinia virus (also belonging to the Orthopoxvirus genus). On the other hand, one study has demonstrated the pronounced susceptibility of the adult albino rabbit and of young animals of several rodent species to Monkeypox virus (MPXV). Given the susceptibility to MPXV of prairie dogs, which are American Sciuridae, the potential for infection of European squirrels cannot be ruled out.


Assuntos
Mpox , Adulto , Animais , Bovinos , Feminino , Humanos , Mpox/epidemiologia , Mpox/veterinária , Monkeypox virus , Coelhos , Sciuridae , Estados Unidos
10.
Viruses ; 13(11)2021 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-34835061

RESUMO

Tick-borne encephalitis virus (TBEV), a member of the Flaviviridae family, Flavivirus genus, is responsible for neurological symptoms that may cause permanent disability or death. With an incidence on the rise, it is the major arbovirus affecting humans in Central/Northern Europe and North-Eastern Asia. Neuronal death is a critical feature of TBEV infection, yet little is known about the type of death and the molecular mechanisms involved. In this study, we used a recently established pathological model of TBEV infection based on human neuronal/glial cells differentiated from fetal neural progenitors and transcriptomic approaches to tackle this question. We confirmed the occurrence of apoptotic death in these cultures and further showed that genes involved in pyroptotic death were up-regulated, suggesting that this type of death also occurs in TBEV-infected human brain cells. On the contrary, no up-regulation of major autophagic genes was found. Furthermore, we demonstrated an up-regulation of a cluster of genes belonging to the extrinsic apoptotic pathway and revealed the cellular types expressing them. Our results suggest that neuronal death occurs by multiple mechanisms in TBEV-infected human neuronal/glial cells, thus providing a first insight into the molecular pathways that may be involved in neuronal death when the human brain is infected by TBEV.


Assuntos
Apoptose , Vírus da Encefalite Transmitidos por Carrapatos/patogenicidade , Neuroglia/virologia , Neurônios/virologia , Piroptose , Apoptose/genética , Astrócitos/metabolismo , Humanos , Neuroglia/metabolismo , Neuroglia/patologia , Neurônios/metabolismo , Neurônios/patologia , Piroptose/genética , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/genética , Ligante Indutor de Apoptose Relacionado a TNF/genética , Transcriptoma
11.
Animal ; 15(6): 100241, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34091225

RESUMO

The ongoing coronavirus disease 19s pandemic has yet again demonstrated the importance of the human-animal interface in the emergence of zoonotic diseases, and in particular the role of wildlife and livestock species as potential hosts and virus reservoirs. As most diseases emerge out of the human-animal interface, a better understanding of the specific drivers and mechanisms involved is crucial to prepare for future disease outbreaks. Interactions between wildlife and livestock systems contribute to the emergence of zoonotic diseases, especially in the face of globalization, habitat fragmentation and destruction and climate change. As several groups of viruses and bacteria are more likely to emerge, we focus on pathogenic viruses of the Bunyavirales, Coronaviridae, Flaviviridae, Orthomyxoviridae, and Paramyxoviridae, as well as bacterial species including Mycobacterium sp., Brucella sp., Bacillus anthracis and Coxiella burnetii. Noteworthy, it was difficult to predict the drivers of disease emergence in the past, even for well-known pathogens. Thus, an improved surveillance in hotspot areas and the availability of fast, effective, and adaptable control measures would definitely contribute to preparedness. We here propose strategies to mitigate the risk of emergence and/or re-emergence of prioritized pathogens to prevent future epidemics.


Assuntos
Animais Selvagens , COVID-19 , Animais , COVID-19/veterinária , Humanos , Gado , SARS-CoV-2 , Zoonoses
12.
J Hum Hypertens ; 35(8): 657-666, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33654233

RESUMO

This review aims to explore the burden of hypertension among refugees in the Middle East by reporting its prevalence, risk factors and access to care. A comprehensive literature search was performed using Web of Science, Ovid MEDLINE, PubMed, SCOPUS, CINHAL+, WHO Regional Office for the Eastern Mediterranean (EMRO) and United Nations High Commissioner for Refugees (UNHCR) on articles spanning from 1948 until 2020. Most studies were cross-sectional in design. After applying eligibility criteria 17 articles and 4 reports were included. Findings showed that hypertension represents a major burden among refugees. Hypertension risk factors present among the refugee population included increased salt intake, physical inactivity, and smoking. The majority of hypertensive refugees sought care for their condition at the public health care services. Barriers to seeking care included high cost of healthcare, accessibility to provided services, and lack of knowledge for the need to seek care. Non-adherence to medication among refugees was primarily linked to cost and lack of symptoms. This review highlights the need for further studies to shed light on the importance of targeting hypertension among refugees, to lower morbidity and mortality, in addition to providing adequate healthcare services to this population.


Assuntos
Hipertensão , Refugiados , Estudos Transversais , Humanos , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Oriente Médio/epidemiologia
13.
Pathogens ; 10(1)2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33466622

RESUMO

Neuropeptides are small signaling molecules expressed in the tick central nervous system, i.e., the synganglion. The neuronal-like Ixodes scapularis embryonic cell line, ISE6, is an effective tool frequently used for examining tick-pathogen interactions. We detected 37 neuropeptide transcripts in the I. scapularis ISE6 cell line using in silico methods, and six of these neuropeptide genes were used for experimental validation. Among these six neuropeptide genes, the tachykinin-related peptide (TRP) of ISE6 cells varied in transcript expression depending on the infection strain of the tick-borne pathogen, Anaplasma phagocytophilum. The immunocytochemistry of TRP revealed cytoplasmic expression in a prominent ISE6 cell subpopulation. The presence of TRP was also confirmed in A. phagocytophilum-infected ISE6 cells. The in situ hybridization and immunohistochemistry of TRP of I. scapularis synganglion revealed expression in distinct neuronal cells. In addition, TRP immunoreaction was detected in axons exiting the synganglion via peripheral nerves as well as in hemal nerve-associated lateral segmental organs. The characterization of a complete Ixodes neuropeptidome in ISE6 cells may serve as an effective in vitro tool to study how tick-borne pathogens interact with synganglion components that are vital to tick physiology. Therefore, our current study is a potential stepping stone for in vivo experiments to further examine the neuronal basis of tick-pathogen interactions.

14.
Transbound Emerg Dis ; 68(2): 626-636, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32654387

RESUMO

Infection with the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) induces the coronavirus infectious disease 19 (COVID-19). Its pandemic form in human population and its probable animal origin, along with recent case reports in pets, make drivers of emergence crucial in domestic carnivore pets, especially cats, dogs and ferrets. Few data are available in these species; we first listed forty-six possible drivers of emergence of COVID-19 in pets, regrouped in eight domains (i.e. pathogen/disease characteristics, spatial-temporal distance of outbreaks, ability to monitor, disease treatment and control, characteristics of pets, changes in climate conditions, wildlife interface, human activity, and economic and trade activities). Secondly, we developed a scoring system per driver, then elicited scientific experts (N = 33) to: (a) allocate a score to each driver, (b) weight the drivers scores within each domain and (c) weight the different domains between them. Thirdly, an overall weighted score per driver was calculated; drivers were ranked in decreasing order. Fourthly, a regression tree analysis was used to group drivers with comparable likelihood to play a role in the emergence of COVID-19 in pets. Finally, the robustness of the expert elicitation was verified. Five drivers were ranked with the highest probability to play a key role in the emergence of COVID-19 in pets: availability and quality of diagnostic tools, human density close to pets, ability of preventive/control measures to avoid the disease introduction or spread in a country (except treatment, vaccination and reservoir(s) control), current species specificity of the disease-causing agent and current knowledge on the pathogen. As scientific knowledge on the topic is scarce and still uncertain, expert elicitation of knowledge, in addition with clustering and sensitivity analyses, is of prime importance to prioritize future studies, starting from the top five drivers. The present methodology is applicable to other emerging pet diseases.


Assuntos
COVID-19/veterinária , Doenças do Gato/epidemiologia , Doenças do Cão/epidemiologia , Pandemias/veterinária , SARS-CoV-2 , Animais , COVID-19/epidemiologia , Doenças do Gato/etiologia , Gatos , Doenças do Cão/etiologia , Cães , Furões , Saúde Global
15.
Pathogens ; 9(11)2020 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-33113771

RESUMO

Arthropod-borne hemoparasites represent a serious health problem in livestock, causing significant production losses. Currently, the evidence of Anaplasma spp., Theileria spp., Babesia spp., and hemotropic Mycoplasma spp. in Algeria remains limited to a few scattered geographical regions. In this work, our objectives were to study the prevalence of these vector-borne pathogens and to search other agents not yet described in Algeria as well as the identification of statistical associations with various risk factors in cattle in the northeast of Algeria. Among the 205 cattle blood samples tested by PCR analysis, 42.4% positive results were obtained for at least one pathogen. The overall rates of Anaplasma spp., Theileria/Babesia spp., and Mycoplasma spp. in the cattle sampled were respectively 30.7%, 18.5%, and 2.9%; co-infections with multiple species was also detected. Anaplasma spp. and Theileria/Babesia spp. were detected at a higher rate in cattle under 3 years old, according to univariate analysis. Anaplasma spp. DNA was detected more frequently in our sample in cattle living in semi extensive farming. Our study provides additional data about Anaplasma spp., Theileria/Babesia spp. and reveals for the first time that Mycoplasma wenyonii and 'Candidatus Mycoplasma hemobos are present in cattle in Northeast Algeria.

16.
Int J Mol Sci ; 21(15)2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32722052

RESUMO

Microvascular endothelial cells constitute potential targets for exogenous microorganisms, in particular for vector-borne pathogens. Their phenotypic and functional variations according to the organs they are coming from provide an explanation of the organ selectivity expressed in vivo by pathogens. In order to make available relevant tools for in vitro studies of infection mechanisms, our aim was to immortalize bovine organospecific endothelial cells but also to assess their permissivity to viral infection. Using transfection with SV40 large T antigen, six bovine microvascular endothelial cell lines from various organs and one macrovascular cell line from an umbilical cord were established. They display their own panel of endothelial progenitor/mature markers, as assessed by flow cytometry and RT-qPCR, as well as the typical angiogenesis capacity. Using both Bluetongue and foot-and-mouth disease viruses, we demonstrate that some cell lines are preferentially infected. In addition, they can be transfected and are able to express viral proteins such as BTV8-NS3. Such microvascular endothelial cell lines bring innovative tools for in vitro studies of infection by viruses or bacteria, allowing for the study of host-pathogen interaction mechanisms with the actual in vivo target cells. They are also suitable for applications linked to microvascularization, such as anti-angiogenic and anti-tumor research, growing fields in veterinary medicine.


Assuntos
Células Endoteliais/metabolismo , Microvasos/metabolismo , Modelos Biológicos , Viroses , Animais , Bovinos , Linhagem Celular , Células Endoteliais/patologia , Células Endoteliais/virologia , Microvasos/patologia , Microvasos/virologia
17.
J Neuroinflammation ; 17(1): 76, 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32127025

RESUMO

BACKGROUND: Tick-borne encephalitis virus (TBEV) is a member of the Flaviviridae family, Flavivirus genus, which includes several important human pathogens. It is responsible for neurological symptoms that may cause permanent disability or death, and, from a medical point of view, is the major arbovirus in Central/Northern Europe and North-Eastern Asia. TBEV tropism is critical for neuropathogenesis, yet little is known about the molecular mechanisms that govern the susceptibility of human brain cells to the virus. In this study, we sought to establish and characterize a new in vitro model of TBEV infection in the human brain and to decipher cell type-specific innate immunity and its relation to TBEV tropism and neuropathogenesis. METHOD: Human neuronal/glial cells were differentiated from neural progenitor cells and infected with the TBEV-Hypr strain. Kinetics of infection, cellular tropism, and cellular responses, including innate immune responses, were characterized by measuring viral genome and viral titer, performing immunofluorescence, enumerating the different cellular types, and determining their rate of infection and by performing PCR array and qRT-PCR. The specific response of neurons and astrocytes was analyzed using the same approaches after enrichment of the neuronal/glial cultures for each cellular subtype. RESULTS: We showed that infection of human neuronal/glial cells mimicked three major hallmarks of TBEV infection in the human brain, namely, preferential neuronal tropism, neuronal death, and astrogliosis. We further showed that these cells conserved their capacity to mount an antiviral response against TBEV. TBEV-infected neuronal/glial cells, therefore, represented a highly relevant pathological model. By enriching the cultures for either neurons or astrocytes, we further demonstrated qualitative and quantitative differential innate immune responses in the two cell types that correlated with their particular susceptibility to TBEV. CONCLUSION: Our results thus reveal that cell type-specific innate immunity is likely to contribute to shaping TBEV tropism for human brain cells. They describe a new in vitro model for in-depth study of TBEV-induced neuropathogenesis and improve our understanding of the mechanisms by which neurotropic viruses target and damage human brain cells.


Assuntos
Astrócitos/imunologia , Astrócitos/virologia , Encefalite Transmitida por Carrapatos/imunologia , Encefalite Transmitida por Carrapatos/virologia , Neurônios/imunologia , Neurônios/virologia , Técnicas de Cultura de Células/métodos , Células Cultivadas , Suscetibilidade a Doenças , Vírus da Encefalite Transmitidos por Carrapatos/fisiologia , Humanos , Imunidade Inata , Tropismo Viral
18.
Rev Prat ; 69(3): 336-340, 2019 Mar.
Artigo em Francês | MEDLINE | ID: mdl-30983266

RESUMO

Zoonoses related to leisure activities. Many zoonoses can be contracted by humans during recreational activities. In the context of a walk, some of them, such as Lyme disease, are transmissible by biological vectors, particularly ticks, or by aerosol (Q fever, hantavirose), whereas others can be contracted in case of aquatic activities (leptospirosis), hunting (tularaemia), and visits to pet farms or fairs (especially the hemolytic uremic syndrome). The risk is increased by the taste of urban populations for outdoor activities and by their ignorance of the risks associated with wild and domestic animals. In addition, current climate changes are accompanied by an increase in the incidence of certain zoonoses already present and with a risk of emergence of zoonoses still unknown in France. Vigilance is therefore essential, as well as a good knowledge of the appropriate methods for prevention and control, including the active participation of target populations.


Zoonoses liées aux activités de loisirs. Nombre de zoonoses peuvent être contractées par l'homme lors d'activités de loisirs. Elles peuvent l'être dans le contexte d'une promenade, comme celles transmissibles par des vecteurs biologiques, en particulier les tiques (cas de la maladie de Lyme), ou par aérosol (fièvre Q, hantavirose), mais aussi d'activités aquatiques (leptospirose), de chasse (tularémie), de visites de fermes pédagogiques ou de foires (notamment le syndrome hémolytique et urémique). Le risque se trouve accru par le goût des populations urbaines pour les activités de plein air et par leur méconnaissance des risques associés aux animaux sauvages et domestiques. En outre, les changements climatiques actuels sont accompagnés par une augmentation de l'incidence de certaines zoonoses déjà présentes et à un risque d'émergence de zoonoses encore inconnues en France. La vigilance s'impose donc, ainsi qu'une bonne connaissance des méthodes appropriées de prévention et de lutte, incluant la participation active des populations cibles.


Assuntos
Atividades de Lazer , Zoonoses , Animais , França , Humanos , Doença de Lyme
19.
Pan Afr Med J ; 29: 5, 2018.
Artigo em Francês | MEDLINE | ID: mdl-29632627

RESUMO

Necrobiosis lipoidica is a rare granulomatous dermatosis. It occurs in 0.3-1.2% of diabetic patients mainly at the level of the leg. The lesions appear as erythematous plaques with central depressions. We here report the case of a 21-year old female patient with a 6-year history of type 1 diabetes presenting with a 1-year history of well circumscribed, symmetrical and asymptomatic erythematous plaques with atrophic yellowish center at the level of the anterior compartments of the legs (A, B). The diagnosis of necrobiosis lipoidica was suspected, a biopsy was performed which confirmed the diagnosis. The patient had a granulomatous inflammatory reaction with palisade-like border disposed around poorly delimited foci of altered connective tissue on the entire dermis layer. The inflammatory reaction was also characterized by multinucleate giant cells, dendrocytes and lipid deposits. Local corticosteroid therapy was prescribed. Patient's evolution was marked by the persistence of the lesions.


Assuntos
Corticosteroides/administração & dosagem , Diabetes Mellitus Tipo 1/complicações , Necrobiose Lipoídica/diagnóstico , Biópsia , Feminino , Humanos , Necrobiose Lipoídica/tratamento farmacológico , Necrobiose Lipoídica/etiologia , Adulto Jovem
20.
Parasit Vectors ; 11(1): 163, 2018 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-29523202

RESUMO

BACKGROUND: Anaplasma phagocytophilum is a zoonotic tick-borne intracellular alpha-proteobacterium causing tick-borne fever, which leads to significant economic losses in domestic ruminants in Europe. Its epidemiological cycles are complex and reservoir host species of bovine strains have not yet been identified. Given that little genetic information is available on strains circulating within a defined bovine environment, our objective was to assess the genetic diversity of A. phagocytophilum obtained from the same farms over time. METHODS: Blood samplings were performed several times in two European herds. In the French herd, 169 EDTA-blood samples were obtained from 115 cows (32 were sampled two to four times). In the German herd, 20 cows were sampled six times (120 EDTA-blood samples). The presence of A. phagocytophilum DNA was assessed using a qPCR targeting msp2. The positive DNA samples underwent MLST at nine genetic markers (typA, ctrA, msp4, pleD, recG, polA, groEL, gyrA, and ankA). For each locus, sequences were aligned with available bacterial sequences derived from cattle, horse, dog, and roe deer hosts, and concatenated neighbor joining trees were constructed using three to six loci. RESULTS: Around 20% (57/289) of samples were positive. Forty positive samples from 23 French and six German cows (11 of them being positive at two time points) were sequenced. Six loci (typA, ctrA, msp4, pleD, recG, and polA) allowed to build concatenated phylogenetic trees, which led to two distinct groups of bovine variants in the French herd (hereafter called A and B), whereas only group A was detected in the German herd. In 42% of French samples, double chromatogram peaks were encountered in up to four loci. Eleven cows were found infected three weeks to 17 months after first sampling and harboured a new variant belonging to one or the other group. CONCLUSIONS: Our results demonstrate the occurrence of two major bovine strain groups and the simultaneous infection of single cows by more than one A. phagocytophilum strain. This challenges the role of cattle as reservoirs for A. phagocytophilum. This role may be facilitated via long-term bacterial persistence in individual cows and active circulation at the herd scale.


Assuntos
Anaplasma phagocytophilum/classificação , Anaplasma phagocytophilum/isolamento & purificação , Doenças dos Bovinos/microbiologia , Coinfecção/veterinária , Reservatórios de Doenças/microbiologia , Ehrlichiose/veterinária , Variação Genética , Anaplasma phagocytophilum/genética , Animais , Sangue/microbiologia , Bovinos , Coinfecção/microbiologia , DNA Bacteriano/química , DNA Bacteriano/genética , Ehrlichiose/microbiologia , França , Genótipo , Alemanha , Tipagem de Sequências Multilocus , Reação em Cadeia da Polimerase em Tempo Real
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