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1.
Reprod Fertil Dev ; 30(2): 272-285, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28679462

RESUMO

The zona pellucida (ZP) is an extracellular envelope that surrounds mammalian oocytes. This coat participates in the interaction between gametes, induction of the acrosome reaction, block of polyspermy and protection of the oviductal embryo. Previous studies suggested that carnivore ZP was formed by three glycoproteins (ZP2, ZP3 and ZP4), with ZP1 being a pseudogene. However, a recent study in the cat found that all four proteins were expressed. In the present study, in silico and molecular analyses were performed in several carnivores to clarify the ZP composition in this order of mammals. The in silico analysis demonstrated the presence of the ZP1 gene in five carnivores: cheetah, panda, polar bear, tiger and walrus, whereas in the Antarctic fur seal and the Weddell seal there was evidence of pseudogenisation. Molecular analysis showed the presence of four ZP transcripts in ferret ovaries (ZP1, ZP2, ZP3 and ZP4) and three in fox ovaries (ZP2, ZP3 and ZP4). Analysis of the fox ZP1 gene showed the presence of a stop codon. The results strongly suggest that all four ZP genes are expressed in most carnivores, whereas ZP1 pseudogenisation seems to have independently affected three families (Canidae, Otariidae and Phocidae) of the carnivore tree.


Assuntos
Carnívoros/genética , Ovário/metabolismo , Pseudogenes , Glicoproteínas da Zona Pelúcida/genética , Zona Pelúcida/metabolismo , Animais , Carnívoros/metabolismo , Evolução Molecular , Feminino , Regulação da Expressão Gênica , Filogenia , Especificidade da Espécie , Glicoproteínas da Zona Pelúcida/metabolismo
2.
Rev Epidemiol Sante Publique ; 66(1): 7-17, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29233572

RESUMO

BACKGROUND: In a context of the evolution of severe morbidities in patients living with HIV (PLWH), the aim of this study was to describe reasons for hospitalization and the mode of care for the patients requiring hospitalization. METHODS: All admissions (≥24h) of PLWH to 10 hospitals in the south of Paris (COREVIH Ile-de-France Sud) between 1/1/2011 and 12/31/2011 were identified. The hospital database and the file of patients followed in the HIV referral department of each hospital were matched. Detailed clinical and biological data were collected, by returning to the individual medical records, for a random sample (65% of hospitalized patients). RESULTS: A total of 3013 hospitalizations (1489 patients) were recorded in 2011. The estimated rate of hospitalized patients was about 8% among the 10105 PLWH routinely managed in COREVIH Ile-de-France Sud in 2011. The majority (58.5%) of these hospitalizations occurred in a unit other than the HIV referral unit. Non-AIDS-defining infections were the main reason for admission (16.4%), followed by HIV-related diseases (15.6%), hepatic/gastrointestinal diseases (12.0%), and cardiovascular diseases (10.3%). The median length of stay was 5 days overall (IQR: 2-11), it was longer among patients admitted to a referral HIV care unit than to another ward. HIV infection had been diagnosed >10 years previously in 61.4% of these hospitalized patients. They often had associated comorbidities (coinfection HCV/HVB 40.5%, smoking 45.8%; hypertension 33.4%, dyslipidemia 28.8%, diabetes 14.8%). Subjects over 60 years old accounted for 15% of hospitalized patients, most of them were virologically controlled under HIV treatment, and cardiovascular diseases were their leading reason for admission. CONCLUSION: Needs for hospitalization among PLWH remain important, with a wide variety in causes of admission, involving all hospital departments. It is essential to prevent comorbidities to reduce these hospitalizations, and to maintain a link between the management of PLWH, that becomes rightly, increasing ambulatory, and recourse to specialized inpatient services.


Assuntos
Atenção à Saúde/estatística & dados numéricos , Infecções por HIV/epidemiologia , Necessidades e Demandas de Serviços de Saúde , Hospitalização/estatística & dados numéricos , Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Adulto , Comorbidade , Atenção à Saúde/normas , Feminino , Infecções por HIV/complicações , HIV-1 , Necessidades e Demandas de Serviços de Saúde/estatística & dados numéricos , Necessidades e Demandas de Serviços de Saúde/tendências , Departamentos Hospitalares/estatística & dados numéricos , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Paris/epidemiologia , Adulto Jovem
3.
Ann Oncol ; 27(3): 397-408, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26681686

RESUMO

Malignancies represent a major cause of morbidity and mortality in human immunodeficiency virus (HIV)-infected patients. The introduction of combined antiretroviral therapy has modified the spectrum of malignancies in HIV infection with a decreased incidence of acquired immunodeficiency syndrome (AIDS) malignancies such as Kaposi's sarcoma and non-Hodgkin's lymphoma due to partial immune recovery and an increase in non-AIDS-defining malignancies due to prolonged survival. Management of HIV-infected patients with cancer requires a multidisciplinary approach, involving both oncologists and HIV physicians to optimally manage both diseases and drug interactions between anticancer and anti-HIV drugs. The French CANCERVIH group presents here a review and an experience of managing non-AIDS malignancies in HIV-infected individuals.


Assuntos
Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Terapia Antirretroviral de Alta Atividade , Doença de Hodgkin/epidemiologia , Sarcoma de Kaposi/epidemiologia , Consenso , Prova Pericial , Doença de Hodgkin/terapia , Humanos , Prognóstico , Risco , Sarcoma de Kaposi/terapia
4.
Br J Dermatol ; 175(6): 1251-1262, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27177037

RESUMO

BACKGROUND: Recent studies have independently implicated the chemokine CXCL12 and its receptors, CXCR4 and CXCR7, in the pathophysiology of Kaposi sarcoma (KS). OBJECTIVES: We investigated whether the CXCL12/CXCR4-CXCR7 protein trio could constitute KS biomarkers. METHODS: Endothelial and spindle cells positive for CXCL12/CXCR4-CXCR7, human herpesvirus-8 latency-associated nuclear antigen (LANA), Ki67 antigen (proliferation) and vascular endothelial growth factor (VEGF) were quantitated in skin lesions from patients with AIDS-associated KS, patients with classic KS and patients with angiomas, using immunohistochemistry and quantitative image analysis (16, 21 and 20 skin lesions, respectively). Plasma CXCL12 concentrations were measured by enzyme-linked immunosorbent assay from 20 patients with AIDS-KS, 12 HIV-infected patients without KS and 13 healthy donors' samples. RESULTS: Cells positive for CXCL12, CXCR4, CXCR7, LANA, Ki67 and VEGF were significantly enriched in patients with AIDS-associated KS and classic KS vs. angiomas (P < 0·001), and in nodular vs. macular/papular KS lesions (P < 0·05). CXCL12, CXCR4 and CXCR7 detection correlated with LANA, Ki67 and VEGF detection (r > 0·4; P < 0·05). However, plasma CXCL12 concentrations did not differ between patients with AIDS-associated KS, HIV-infected patients without KS, and healthy donors. CONCLUSIONS: The CXCL12/CXCR4-CXCR7 trio is upregulated in KS and correlates with KS pathophysiological markers and the severity of skin lesions. Histological assessment of the CXCL12 axis could serve as a valuable biomarker for KS diagnosis and progression.


Assuntos
Biomarcadores Tumorais/metabolismo , Quimiocina CXCL12/metabolismo , Receptores CXCR4/metabolismo , Receptores CXCR/metabolismo , Sarcoma de Kaposi/metabolismo , Neoplasias Cutâneas/metabolismo , Adulto , Inibidores da Angiogênese/uso terapêutico , Antígenos Virais/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Lenalidomida , Masculino , Proteínas Nucleares/metabolismo , Talidomida/análogos & derivados , Talidomida/uso terapêutico , Fator A de Crescimento do Endotélio Vascular/metabolismo
5.
J Helminthol ; 90(3): 279-83, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-25727141

RESUMO

The Echinococcus granulosus tapeworm is responsible for cystic echinococcosis (CE), a zoonotic disease with worldwide distribution. The life cycle of the parasite is mainly domestic and takes place between dogs and livestock species. A slaughterhouse survey was conducted in 2012 in the Republic of Moldova in order to estimate the prevalence of CE. A total of 1525 cattle, 5580 sheep and 12,700 pigs were surveyed. No CE infection was observed in pigs, while prevalence was estimated at 59.3% in cattle and 61.9% in sheep. Infection was significantly higher in animals raised in private households than in those from collective farms. The frequency of infection increased with age in both species. In cattle and in sheep, infection of both the liver and lungs was the most common, while infection in the lungs only was much less frequent. Farm type appears to be an important factor in CE infection in Moldova, due to the extensive farming and the home-slaughtering undertaken in the majority private sector, despite a high prevalence of CE also recorded in the public sector. The low fertility of cysts in cattle (1.1%) compared to sheep (47.6%) confirmed the maintenance of E. granulosus sensu stricto in a dog-sheep life cycle which excludes cattle. Further studies are needed to obtain a complete overview of the parasite's epidemiology in its intermediate and definitive hosts, in order to implement control and preventive measures, with specific attention given to farms in the private sector.


Assuntos
Matadouros , Doenças dos Bovinos/epidemiologia , Equinococose/veterinária , Echinococcus granulosus/isolamento & purificação , Doenças dos Ovinos/epidemiologia , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Equinococose/epidemiologia , Moldávia/epidemiologia , Prevalência , Ovinos , Doenças dos Ovinos/parasitologia
6.
Ann Oncol ; 26(5): 958-966, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25632071

RESUMO

BACKGROUND: We undertook the present analysis to examine the shifting influence of prognostic factors in HIV-positive patients diagnosed with aggressive non-Hodgkin lymphoma (NHL) over the last two decades. PATIENTS AND METHODS: We carried out a pooled analysis from an existing database of patients with AIDS-related lymphoma. Individual patient data had been obtained prior from prospective phase II or III clinical trials carried out between 1990 until 2010 in North America and Europe that studied chemo(immuno)therapy in HIV-positive patients diagnosed with AIDS-related lymphomas. Studies had been identified by a systematic review. We analyzed patient-level data for 1546 patients with AIDS-related lymphomas using logistic regression and Cox proportional hazard models to identify the association of patient-, lymphoma-, and HIV-specific variables with the outcomes complete response (CR), progression-free survival, and overall survival (OS) in different eras: pre-cART (1989-1995), early cART (1996-2000), recent cART (2001-2004), and contemporary cART era (2005-2010). RESULTS: Outcomes for patients with AIDS-related diffuse large B-cell lymphoma and Burkitt lymphoma improved significantly over time, irrespective of baseline CD4 count or age-adjusted International Prognostic Index (IPI) risk category. Two-year OS was best in the contemporary era: 67% and 75% compared with 24% and 37% in the pre-cART era (P < 0.001). While the age-adjusted IPI was a significant predictor of outcome in all time periods, the influence of other factors waxed and waned. Individual HIV-related factors such as low CD4 counts (<50/mm(3)) and prior history of AIDS were no longer associated with poor outcomes in the contemporary era. CONCLUSIONS: Our results demonstrate a significant improvement of CR rate and survival for all patients with AIDS-related lymphomas. Effective HIV-directed therapies reduce the impact of HIV-related prognostic factors on outcomes and allow curative antilymphoma therapy for the majority of patients with aggressive NHL.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Antineoplásicos/uso terapêutico , Infecções por HIV/terapia , Imunoterapia/métodos , Linfoma Relacionado a AIDS/terapia , Linfoma não Hodgkin/terapia , Adolescente , Adulto , Idoso , Fármacos Anti-HIV/efeitos adversos , Antineoplásicos/efeitos adversos , Distribuição de Qui-Quadrado , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Bases de Dados Factuais , Progressão da Doença , Intervalo Livre de Doença , Europa (Continente) , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/imunologia , Infecções por HIV/mortalidade , Humanos , Imunoterapia/efeitos adversos , Estimativa de Kaplan-Meier , Modelos Logísticos , Linfoma Relacionado a AIDS/diagnóstico , Linfoma Relacionado a AIDS/imunologia , Linfoma Relacionado a AIDS/mortalidade , Linfoma não Hodgkin/diagnóstico , Linfoma não Hodgkin/imunologia , Linfoma não Hodgkin/mortalidade , Masculino , Pessoa de Meia-Idade , Análise Multivariada , América do Norte , Modelos de Riscos Proporcionais , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
7.
Mediators Inflamm ; 2015: 792173, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25922564

RESUMO

BACKGROUND: There are few data on anakinra use after failure of conventional medications for crystal-induced peripheral arthritis and/or crowned dens syndrome among complex hospitalized patients. METHODS: We retrospectively analyzed the outcome of six patients affected with subacute crystal-induced arthritis who had received anakinra in second or third line therapy, including three patients with crowned dens syndrome and three others with gouty arthritis. Patients' comorbidities, reasons for anakinra use and associated drugs, and outcomes were recorded. RESULTS: All patients presented with elevated inflammatory syndrome, systemic symptoms with poly/oligoarthritis. Except for absolute contraindications, all patients were previously treated with full or decreased dose of NSAID, colchicine, and/or glucocorticoids, with unsatisfactory response. All three gouty patients exhibited complete responses in all acute involvements under anakinra within 3 to 5 days, including one of them who needed the reintroduction of colchicine treatment that was previously unsuccessful. Crowned dens syndrome patients, including two with pseudogout and one with subacute hydroxyapatite deposition disease, needed 9 to 11 days to achieve complete response. Tolerance to anakinra was good. CONCLUSION: In case series of complex hospitalized patients, anakinra showed good activity in crowned dens syndrome and associated crystal-induced peripheral arthritis, with longer treatment duration than in gouty arthritis.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Gotosa/tratamento farmacológico , Artrite/tratamento farmacológico , Proteína Antagonista do Receptor de Interleucina 1/uso terapêutico , Idoso , Anti-Inflamatórios não Esteroides/uso terapêutico , Proteína C-Reativa/metabolismo , Colchicina/uso terapêutico , Comorbidade , Feminino , Glucocorticoides/uso terapêutico , Hospitalização , Humanos , Inflamação/tratamento farmacológico , Masculino , Estudos Retrospectivos , Resultado do Tratamento
8.
Parasitol Res ; 112(4): 1809-12, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23271567

RESUMO

Human cystic echinococcosis (hydatid disease) caused by the Echinococcus granulosus tapeworm continues to be a substantial cause of morbidity and mortality in many parts of the world. France is still considered as endemic area, but the current infestation by E. granulosus of intermediate hosts in France remains currently unknown due to the absence of official data reporting for the last 20 years. A 1-year prevalence survey was conducted in the 24 slaughterhouses of ten departments of the South of France. We demonstrate that the E. granulosus parasite is still currently present at low prevalence at slaughterhouses in the study area (4 cases for 100,000 sheep and 3 cases for 100,000 cattle). In addition, we assess the presence of genotype G1 in infected animals and identify for the first time in France genotypes G2 and G3 of E. granulosus sensu stricto.


Assuntos
Doenças dos Bovinos/epidemiologia , Equinococose/epidemiologia , Echinococcus granulosus/isolamento & purificação , Doenças dos Ovinos/epidemiologia , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Estudos Transversais , DNA de Helmintos/química , DNA de Helmintos/genética , Equinococose/parasitologia , Echinococcus granulosus/classificação , Echinococcus granulosus/genética , França/epidemiologia , Genótipo , Dados de Sequência Molecular , Prevalência , Análise de Sequência de DNA , Ovinos , Doenças dos Ovinos/parasitologia
9.
HIV Med ; 13(8): 479-87, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22414000

RESUMO

BACKGROUND: AIDS-related lymphoma (ARL) remains the main cause of AIDS-related deaths in the combined antiretroviral therapy (cART) era. Although most ARLs are associated with the Epstein-Barr virus (EBV), whether patients with high EBV burden are more at risk of developing ARL is unknown. This study investigated the relationship between high blood EBV DNA loads and subsequent progression to ARL. METHODS: We identified 43 cases of ARL diagnosed between 1988 and 2007 within two cohorts (ANRS SEROCO/HEMOCO and PRIMO) and for which stored serum and peripheral blood mononuclear cell (PBMC) samples were available within 3 years before ARL diagnosis. For each case, two controls matched for the cohort and CD4 cell count in the year of ARL diagnosis were selected. EBV DNA was measured in PBMCs and serum samples with a commercial kit. RESULTS: High levels of EBV DNA in PBMCs collected a median of 10 months before diagnosis were associated with an increased risk of developing systemic B lymphoma (adjusted odds ratio 2.47; 95% confidence interval 1.15; 5.32 for each 1 log copies/10(6) PBMC increase in EBV load) but not with primary brain lymphoma. CONCLUSION: In this study, HIV-infected patients with undetectable EBV DNA in PBMCs did not develop ARL in the following 3 years, while high levels of EBV DNA in PBMCs predicted subsequent progression to systemic B lymphoma. Clinicians should be aware of the increased risk of developing systemic B lymphoma in HIV-infected patients with a high blood EBV DNA load.


Assuntos
DNA Viral/sangue , Infecções por HIV/virologia , Herpesvirus Humano 4/isolamento & purificação , Linfoma Relacionado a AIDS/virologia , Linfoma de Células B/virologia , Adulto , Estudos de Casos e Controles , Estudos de Coortes , Progressão da Doença , Feminino , Infecções por HIV/sangue , Infecções por HIV/complicações , Herpesvirus Humano 4/genética , Humanos , Linfoma Relacionado a AIDS/complicações , Masculino , Razão de Chances , Carga Viral
10.
Epidemics ; 40: 100600, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35809515

RESUMO

Given the difficulty of measuring pathogen transmission in wildlife, epidemiological studies frequently rely on cross-sectional seroprevalence. However, seropositivity indicates only exposure to a pathogen at an unknown time. By allowing to obtain repeated test results from individuals sampled multiple times over an extended period, longitudinal data help reduce this uncertainty. We used capture-mark-recapture data on bank vole (Myodes glareolus) individuals collected at four sites over ten years in northeastern France to investigate the impact of environmental variables on seroprevalence and incidence of Puumala orthohantavirus (PUUV). PUUV causes a chronic infection without apparent symptoms, that may however impair survival of its rodent host in the wild. Viral transmission between rodents may occur through direct contact or via the environment. Principal component analysis was used to deal with multicollinearity among environmental variables. Incidence and seroprevalence were investigated with either generalized estimating equations or Poisson regression models depending on the number of observations for each season. In spring, only the factor site was found to be significant for seroprevalence, while a principal component including meteorological conditions of the previous winter and the normalized difference vegetation index (NDVI) of both the previous winter and spring had a significant effect on incidence. In autumn, only the factor site was significant for incidence, while two principal components, including either the meteorological conditions of the autumn and previous spring or NDVI of the autumn significantly affected seroprevalence. We discuss these results in light of the particular demography of small mammals. We encourage other researchers to investigate the relationships between demographic parameters of wild host populations and the environment, by using both incidence and seroprevalence.


Assuntos
Febre Hemorrágica com Síndrome Renal , Virus Puumala , Animais , Arvicolinae , Estudos Transversais , França/epidemiologia , Febre Hemorrágica com Síndrome Renal/epidemiologia , Incidência , Estações do Ano , Estudos Soroepidemiológicos
11.
Biomacromolecules ; 12(4): 859-70, 2011 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-21381699

RESUMO

We study by small-angle neutron scattering (SANS) the structure of hyaluronan -lysozyme complexes. Hyaluronan (HA) is a polysaccharide of 9 nm intrinsic persistence length that bears one negative charge per disaccharide monomer (M(mol) = 401.3 g/mol); two molecular weights, M(w) = 6000 and 500,000 Da were used. The pH was adjusted at 4.7 and 7.4 so that lysozyme has a global charge of +10 and +8, respectively. The lysozyme concentration was varied from 3 to 40 g/L at constant HA concentration (10 g/L). At low protein concentration, samples are monophasic, and SANS experiments reveal only fluctuations of concentration, although, at high protein concentration, clusters are observed by SANS in the dense phase of the diphasic samples. In between, close to the onset of the phase separation, a distinct original scattering is observed. It is characteristic of a rod-like shape, which could characterize "single" complexes involving one or a few polymer chains. For the large molecular weight (500,000), the rodlike rigid domains extend to much larger length scale than the persistence length of the HA chain alone in solution and the range of the SANS investigation. They can be described as a necklace of proteins attached along a backbone of diameter of one or a few HA chains. For the short chains (M(w) ≈ 6000), the rod length of the complexes is close to the chain contour length (∼ 15 nm).


Assuntos
Eletrólitos/química , Ácido Hialurônico/química , Muramidase/química , Peso Molecular
12.
Epidemiol Infect ; 139(10): 1486-96, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21385516

RESUMO

The purpose of this study was to develop a standardized tool for the assessment of surveillance systems on zoonoses and animal diseases. We reviewed three existing methods and combined them to develop a semi-quantitative assessment tool associating their strengths and providing a standardized way to display multilevel results. We developed a set of 78 assessment criteria divided into ten sections, representing the functional parts of a surveillance system. Each criterion was given a score according to the prescription of a scoring guide. Three graphical assessment outputs were generated using a specific combination of the scores. Output 1 is a general overview through a series of pie charts synthesizing the scores of each section. Output 2 is a histogram representing the quality of eight critical control points. Output 3 is a radar chart representing the level reached by ten system attributes. This tool was applied on five surveillance networks.


Assuntos
Doenças Transmissíveis/veterinária , Inocuidade dos Alimentos/métodos , Administração em Saúde Pública/métodos , Administração em Saúde Pública/normas , Vigilância de Evento Sentinela/veterinária , Zoonoses/epidemiologia , Animais , Doenças Transmissíveis/epidemiologia , França/epidemiologia , Pesquisa sobre Serviços de Saúde
13.
Exp Parasitol ; 128(1): 57-60, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21256846

RESUMO

A modified Segmental Sedimentation and Counting Technique (SSCT) to examine the presence of Echinococcus multilocularis helminths in segments of fox (Vulpes vulpes) intestine is described and compared to the "gold standard", SCT. Out of the 358 intestines collected, 117 were E. multilocularis positive. Using SSCT methods we compare the sensitivity of individual or pairs of segments to establish a tradeoff between saving time and the reliability of the diagnosis, especially in areas with low infection intensities. The results show that the analysis of segment S4 associated with segment S1 or S2 give 98.3% sensitivity, with specificity close to 100%. Based on our results and the time saved, we recommend using SSCT for routine examination of fox intestines for large epidemiological studies, particularly where the endemic prevalence of E. multilocularis is low or unknown.


Assuntos
Equinococose/veterinária , Echinococcus multilocularis/isolamento & purificação , Raposas/parasitologia , Enteropatias Parasitárias/veterinária , Intestinos/parasitologia , Animais , Equinococose/diagnóstico , Equinococose/parasitologia , Echinococcus multilocularis/crescimento & desenvolvimento , Enteropatias Parasitárias/diagnóstico , Enteropatias Parasitárias/parasitologia , Sensibilidade e Especificidade
14.
Biomacromolecules ; 10(6): 1346-57, 2009 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-19425547

RESUMO

We use small angle neutron scattering (SANS), with an original analysis method, to obtain both the characteristic sizes and the inner composition of lysozyme-pectin complexes depending on the charge density. Lysozyme is a globular protein and pectin a natural anionic semiflexible polysaccharide with a degree of methylation (DM) 0, 43, and 74. For our experimental conditions (buffer ionic strength I = 2.5 10(-2) mol/L and pH between 3 and 7), the electrostatic charge of lysozyme is always positive (from 8 to 17, depending on pH). The pectin charge per elementary chain segment is negative and can be varied from almost zero to one through the change of DM and pH. The weight molar ratio of lysozyme on pectin monomers is kept constant. The ratio of negative charge content per volume to positive charge content per volume, -/+, is varied between 10 and 0.007. On a local scale, for all charged pectins, a correlation peak appears at 0.2 A(-1) due to proteins clustering inside the complexes. On a large scale, the complexes appear as formed of spherical globules with a well-defined radius of 10 to 50 nm, containing a few thousands proteins. The volume fraction Phi of organic matter within the globules derived from SANS absolute cross sections is around 0.1. The protein stacking, which occurs inside the globules, is enhanced when pectin is more charged, due to pH or DM. The linear charge density of the pectin determines the size of the globules for pectin chains of comparable molecular weights whether it is controlled by the pH or the DM. The radius of the globules varies between 10 and 50 nm. In conclusion, the structure is driven by electrostatic interactions and not by hydrophobic interactions. The molecular weight also has a large influence on the structure of the complexes because long chains tend to form larger globules. This may be one reason why DM and pH are not completely equivalent in our system, because DM0 has a short mass, but this may not be the only one. For very low pectin charge (-/+ = 0.07), globules do not appear and the scattering signals a gel-like structure. We did not observe any beads-on-a-string structure.


Assuntos
Muramidase/química , Nêutrons , Pectinas/química , Concentração de Íons de Hidrogênio , Espalhamento de Radiação
15.
Food Waterborne Parasitol ; 14: e00034, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32095604

RESUMO

Preventing foodborne pathogen contamination of raw fruit and vegetables in the field is critically important for public health. Specifically, it involves preventing faecal deposit by wildlife or domestic animals in fields of crops and kitchen gardens. The present study aims to identify the drivers of fox, dog and cat faecal deposits in kitchen gardens in order to mitigate the risk of contamination of raw produce with parasites shed in carnivore faeces. The focus was on Echinococcus multilocularis, ranked highest in the importance of foodborne parasites in Europe, but attention was also paid to other parasites of major concern - Toxoplasma gondii and Toxocara spp. During the winters of 2014 to 2016, faecal samples were collected from 192 kitchen gardens located in north-eastern France. From these samples, 77% contained scat of carnivores. Molecular analyses revealed that 59% of the 1016 faeces collected were from cats, 31% from foxes, and 10% from dogs. The ease of accessibility to kitchen gardens, the presence of food in the vicinity, and the composition of the surrounding vegetation were used to explain the distribution of fox and cat faeces. Generalized Linear Mixed Effects modelling showed that: i) fencing was not efficient in reducing cat faecal deposits, but drastically decreases those of foxes; ii) the abundance of Microtus sp. indicates a reason for the presence of both fox and cat faecal deposits, iii) the abundance of Arvicola terrestris, the proximity of fruit trees or farms and the predominance of forest and grassland around the village are all drivers of fox faecal deposits. These results point to the importance of fencing around kitchen gardens located in E. multilocularis endemic areas, particularly those surrounded by forest and grassland or close to fruit trees or farms.

16.
Parasite ; 15(1): 77-85, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18416250

RESUMO

This study evaluated the impact of biological and environmental factors on the infection of red foxes (Vulpes vulpes) by Echinococcus multilocularis in an endemic area of north-east France. From January 2004 to April 2006, 127 foxes were examined for E. multilocularis and their stomach contents analysed. The effect of year, season, age, sex and urbanisation level on E. multilocularis presence was estimated using a General Linear Model (GLM) with logit link, (i.e. logistic regression). Urbanisation level was the only influencing factor, with a decreasing gradient from rural [54%, CI 95% (40-68)] to peri-urban [31%, CI 95% (15-52)] and urban area [4%, CI 95% (0.7-15)]. The consumption of Arvicola terrestris and Microtus sp., grassland species, the main presumed intermediate hosts of E. multilocularis, was studied by the same approach. The two species were consumed less in the urban area and more in autumn than in spring. Anthropogenic food consumption was linked to urbanisation and to age. The frequency of anthropogenic food consumption decreased in the rural area. A global model explaining the presence of E. multilocularis and including urbanisation level and diet was then elaborated. Independently of urbanisation, there was a suggestion of less E. multilocularis infection with anthropogenic food consumption. Red foxes consuming Microtus sp. and A. terrestris had higher worm burden than those that did not. The results suggest that the decreasing gradient observed from rural to urban area is linked to behaviour and feeding habits.


Assuntos
Equinococose/veterinária , Echinococcus multilocularis/isolamento & purificação , Comportamento Alimentar , Raposas/parasitologia , Fatores Etários , Animais , Equinococose/epidemiologia , Echinococcus multilocularis/crescimento & desenvolvimento , Feminino , França/epidemiologia , Masculino , Fatores de Risco , População Rural , Estações do Ano , Fatores Sexuais , População Urbana
17.
Zoonoses Public Health ; 65(5): 540-551, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29577655

RESUMO

In-depth knowledge on the mechanisms that maintain infection by a zoonotic pathogen in an animal reservoir is the key to predicting and preventing transmission to humans. The Puumala orthohantavirus (PUUV), the most prevalent orthohantavirus in Western Europe, causes a mild form of haemorrhagic fever with renal syndrome (HFRS) in humans. In France, this endemic illness affects the north-eastern part of the country. We conducted a 4-year capture-mark-recapture study in a bank vole population, combined with molecular analyses, to explore the epidemiological situation of PUUV in Alsace, a French region where human cases have occurred, but for which no studies have been conducted on this reservoir host. PUUV-infected bank voles were detected in the 2 years that showed high bank vole density with a prevalence of 4%. The individual PUUV sequences identified in this study were similar from year to year and similar to other French sequences. On a very small spatial scale, the distribution of seropositive bank voles was very heterogeneous in time and space. The short distances travelled on average by bank voles resulted in spatial clusters of seropositive rodents, which spread only very gradually throughout the year.


Assuntos
Arvicolinae/virologia , Febre Hemorrágica com Síndrome Renal/veterinária , Camundongos/virologia , Virus Puumala/genética , Animais , França/epidemiologia , Variação Genética , Febre Hemorrágica com Síndrome Renal/epidemiologia , Febre Hemorrágica com Síndrome Renal/virologia , Filogenia , Estudos Soroepidemiológicos
18.
J Immunol Methods ; 318(1-2): 1-10, 2007 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-17166510

RESUMO

This paper reports a new ELISA to measure the level of rabies anti-glycoprotein G antibodies after vaccination. The Platelia Rabies II kit was evaluated on different populations of dogs, cats and foxes. For each target species, sera from naive, unvaccinated and vaccinated animals were tested. Platelia Rabies II results were compared to the reference fluorescent antibody virus neutralisation test (for dogs and cats) and to a published in house ELISA test (for foxes). The Platelia Rabies II test was found to be highly specific whatever the species (more than 98%) using a cut-off value of 0.5 EU/ml. The index of sensitivity was between 92.4% and 94.5% for fox samples, and reached 83% for domestic carnivores. Data collected by testing field samples revealed that the rate of false negative results ranged between 8.9% and 11.1% and the rate of false positive results ranged between 1% and 2% for the dog/cat population. Therefore, the Platelia Rabies II test described here would be a good candidate for routine detection of rabies antibodies not only in domestic carnivores (within the framework of international trade) but also in foxes for the follow up of rabies oral vaccination programs.


Assuntos
Animais Domésticos/imunologia , Animais Selvagens/imunologia , Anticorpos Antivirais/sangue , Carnívoros/imunologia , Vacina Antirrábica/imunologia , Animais , Gatos , Cães , Ensaio de Imunoadsorção Enzimática/métodos , Reações Falso-Negativas , Reações Falso-Positivas , Raposas , Glicoproteínas/imunologia , Testes de Neutralização/métodos , Curva ROC , Raiva/diagnóstico , Raiva/imunologia , Raiva/prevenção & controle , Vírus da Raiva/imunologia , Kit de Reagentes para Diagnóstico/normas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Testes Sorológicos/métodos , Proteínas do Envelope Viral/imunologia
19.
Transbound Emerg Dis ; 64(4): 1210-1228, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26996739

RESUMO

In Europe, the increasing number of nephropathia epidemica (NE) infections in humans, caused by Puumala virus carried by bank voles (Myodes glareolus), has triggered studies of environmental factors driving these infections. NE infections have been shown to occur in specific geographical areas characterized by environmental factors that influence the distribution and dynamics of host populations and virus persistence in the soil. Here, we review the influence of environmental conditions (including climate factors, food availability and habitat conditions) with respect to incidence in humans and seroprevalence in rodents, considering both direct and indirect transmission pathways. For each type of environmental factor, results and discrepancies between studies are presented and examined in the light of biological hypotheses. Overall, food availability and temperature appear to be the main drivers of host seroprevalence and NE incidence, but data quality and statistical approaches varied greatly among studies. We highlight the issues that now need to be addressed and suggest improvements for study design in regard to the current knowledge on hantavirus epidemiology.


Assuntos
Arvicolinae , Meio Ambiente , Febre Hemorrágica com Síndrome Renal/veterinária , Virus Puumala/fisiologia , Doenças dos Roedores/epidemiologia , Doenças dos Roedores/transmissão , Animais , Clima , Ecossistema , Europa (Continente)/epidemiologia , Cadeia Alimentar , Febre Hemorrágica com Síndrome Renal/epidemiologia , Febre Hemorrágica com Síndrome Renal/transmissão , Febre Hemorrágica com Síndrome Renal/virologia , Humanos , Incidência , Prevalência , Doenças dos Roedores/virologia , Estudos Soroepidemiológicos
20.
Acta Trop ; 165: 26-32, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27436811

RESUMO

This study was undertaken in the Province of Sidi Kacem in northwest Morocco between April 2010 and March 2011. The main objective of the study was to determine the prevalence of Echinococcus granulosus (Eg) infection in owned dogs. This province was selected as a case study because of the social conditions, geographic and climatic diversity making it a model representative of many parts of Morocco. The survey was carried out in 23 rural communes and in the 5 municipalities (urban districts) of the Province and sampling was undertaken in randomly selected households. A total of 273 owned dogs comprising 232 from the 23 rural communes (rural dogs) and 41 from the 5 municipalities (urban dogs) were tested. Arecoline hydrobromide purgation was selected as the diagnostic method of choice to enable visualisation of expelled worms by dog owners, thereby imparting messages on the transmission mode of Eg to humans and farm animals. Of the 273 dogs tested, purgation was effective in a total of 224 dogs (82.1%). The overall estimated prevalence of Eg infection was 35.3% (79/224, 95% CI 22.3-47.0%). Dogs inhabiting rural communes were at greater risk of infection (38.0%, 95% CI 31.1-45.3%) than dogs roaming in municipalities or urban areas (18.8%, 95% CI 7.2-36.4%) and the prevalence of infection was higher in those inhabiting rural communes with slaughterhouses (62.7%, 95% CI 48.1-75.9%) than in communes without (29.1%, 95% CI 21.7-37.2%). This first assessment of Eg infection in Sidi Kacem Province indicates a key role of rural slaughterhouses in parasite transmission to dogs.


Assuntos
Doenças do Cão/epidemiologia , Equinococose/veterinária , Echinococcus granulosus/isolamento & purificação , Animais , Doenças do Cão/transmissão , Cães , Equinococose/epidemiologia , Equinococose/transmissão , Humanos , Marrocos/epidemiologia , Prevalência , População Rural , Inquéritos e Questionários , População Urbana
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