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1.
Transbound Emerg Dis ; 65(1): 240-243, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28239954

RESUMO

After its introduction in Turkey in November 2013 and subsequent spread in this country, lumpy skin disease (LSD) was first reported in the western Turkey in May 2015. It was observed in cattle in Greece and reported to the World Organization for Animal Health (OIE) in August 2015. From May 2015 to August 2016, 1,092 outbreaks of lumpy skin disease were reported in cattle from western Turkey and eight Balkan countries: Greece, Bulgaria, The Former Yugoslav Republic of Macedonia, Serbia, Kosovo, and Albania. During this period, the median LSD spread rate was 7.3 km/week. The frequency of outbreaks was highly seasonal, with little or no transmission reported during the winter. Also, the skewed distribution of spread rates suggested two distinct underlying epidemiological processes, associating local and distant spread possibly related to vectors and cattle trade movements, respectively.


Assuntos
Doenças dos Bovinos/transmissão , Surtos de Doenças/veterinária , Transmissão de Doença Infecciosa/veterinária , Doença Nodular Cutânea/transmissão , Vírus da Doença Nodular Cutânea/isolamento & purificação , Animais , Península Balcânica/epidemiologia , Bovinos , Doenças dos Bovinos/virologia , Doença Nodular Cutânea/virologia , Estações do Ano
2.
Parasit Vectors ; 8: 504, 2015 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-26438193

RESUMO

BACKGROUND: Amblyomma variegatum and A. hebraeum are two ticks of veterinary and human health importance in south-east Africa. In Zimbabwe they occupy parapatric (marginally overlapping and juxtaposed) distributions. Understanding the mechanisms behind this parapatry is essential for predicting the spatio-temporal dynamics of Amblyomma spp. and the impacts of associated diseases. It has been hypothesized that exclusive competition between these species results from competition at the levels of male signal reception (attraction-aggregation-attachment pheromones) or sexual competition for mates. This hypothesis predicts that the parapatry described in Zimbabwe could also be present in other countries in the region. METHODS: To explore this competitive exclusion hypothesis we conducted field surveys at the two species' range limits in Mozambique to identify areas of sympatry (overlapping areas) and to study potential interactions (communicative and reproductive interference effects) in those areas. At sympatric sites, hetero-specific mating pairs were collected and inter-specific attractiveness/repellent effects acting at long and short distances were assessed by analyzing species co-occurrences on co-infested herds and co-infested hosts. RESULTS: Co-occurrences of both species at sampling sites were infrequent and localized in areas where both tick and host densities were low. At sympatric sites, high percentages of individuals of both species shared attachment sites on hosts and inter-specific mating rates were high. Although cross-mating rates were not significantly different for A. variegatum and A. hebraeum females, attraction towards hetero-specific males was greater for A. hebraeum females than for A. variegatum females and we observed small asymmetrical repellent effects between males at attachment sites. CONCLUSIONS: Our observations suggest near-symmetrical reproductive interference between A. variegatum and A. hebraeum, despite between-species differences in the strength of reproductive isolation barriers acting at the aggregation, fixation and partner contact levels. Theoretical models predict that sexual competition coupled with hybrid inviability, greatly reduces the probability of one species becoming established in an otherwise suitable location when the other species is already established. This mechanism can explain why the parapatric boundary in Mozambique has formed within an area of low tick densities and relatively infrequent host-mediated dispersal events.


Assuntos
Distribuição Animal/fisiologia , Ixodidae/fisiologia , Animais , Feminino , Hibridização Genética , Masculino , Modelos Biológicos , Moçambique , Reprodução/fisiologia , Especificidade da Espécie
3.
Diagn Interv Imaging ; 96(5): 443-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25758756

RESUMO

Brachydactyly, or shortening of the digits, is due to the abnormal development of phalanges, metacarpals and/or metatarsals. This congenital malformation is common, easily detectable clinically but often requires additional radiological exploration. Radiographs are essential to characterize the type of brachydactyly and to show the location of the bone shortening, as well as any associated malformation. This article reviews the radiological findings for isolated brachydactylies (according to the types classified by Bell, and Temtamy and McKusick) and for brachydactylies that are part of complex multisystem malformation syndromes. If warranted by the clinical and radiological examinations, a genetic analysis (molecular and/or cytogenetic) can confirm the etiologic diagnosis.


Assuntos
Braquidactilia/diagnóstico por imagem , Braquidactilia/classificação , Humanos , Radiografia , Síndrome
4.
Eur J Pediatr ; 174(1): 23-32, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24953377

RESUMO

UNLABELLED: Renovascular hypertension accounts for 5-10 % of hypertension cases in children; there is currently no consensus on treatment. Here, we report on our clinical experience with this disease and outline the different pathways in which to investigate it. We report retrospectively on ten children diagnosed with renovascular hypertension at the University Hospital of Nantes from 2001 to 2012. The main findings were obtained by fortuitous screening of children aged 2 months to 14 years old with neurofibromatosis (n = 2) and fibromuscular dysplasia (n = 8). The hypertension was always severe yet asymptomatic. Lesions were complicated in nine out of ten cases and included bilateral, multiple, mid-aortic syndrome and aneurysm. Doppler ultrasound associated with computed tomography allowed for a precise diagnosis in seven out of ten cases. Where ambiguities persisted, they were highlighted by arteriography, the gold standard investigation. Medical treatment was insufficient, leading to invasive procedures in nine out of ten children: 2 nephrectomies, 2 autotransplantations, and 21 repetitive percutaneous transluminal angioplasties. After invasive procedures, blood pressure control improved in four cases and was resolved in three. CONCLUSION: Arteriography remains to be the gold standard technique for renovascular hypertension in children and can be combined with angioplasty when medical treatment is rendered obsolete. The role of computed tomography is controversial. Despite the heterogeneity of the children studied, we present a general medical and therapeutic management pathway for the treatment of this disease.


Assuntos
Hipertensão Renovascular/diagnóstico , Hipertensão Renovascular/terapia , Adolescente , Angiografia/métodos , Angioplastia , Criança , Pré-Escolar , Feminino , Displasia Fibromuscular/complicações , Humanos , Lactente , Masculino , Neurofibromatose 1/complicações , Sistema Renina-Angiotensina/fisiologia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia Doppler
5.
Arch Pediatr ; 21(11): 1187-94, 2014 Nov.
Artigo em Francês | MEDLINE | ID: mdl-25282460

RESUMO

INTRODUCTION: Congenital portosystemic shunts (CPS) are rare vascular malformations that lead to liver metabolic modifications. The aim of this study was to describe the management and outcome of CPS in children who were followed in the western region of France and to compare our experience to a literature review. PATIENTS AND METHODS: This retrospective study reports nine children with CPS who were followed in the western region of France between 2008 and 2013. RESULTS: Among these nine children, six were detected by prenatal ultrasonography, one had cholestatic jaundice during the postoperative period, one had cholestatic jaundice during the first days of life, and one had dyspnea and fatigue. Two children had liver tumors. The CPS was intrahepatic for four children and extrahepatic for two children. Three others had a patent ductus venosus. Among the intrahepatic shunts that were discovered before the age of 2 years, three closed spontaneously. The five other shunts were closed surgically or by interventional radiology techniques, after angiography for four children. After closure of eight shunts, the outcome was favorable for six children. Two children presented complications after surgery: portal hypertension and portal thrombus. CONCLUSION: When CPS is suspected, the diagnosis should be confirmed and complications should be investigated. Shunt closure restores portal flow and prevents complications.


Assuntos
Veia Porta/anormalidades , Malformações Vasculares/diagnóstico , Malformações Vasculares/terapia , Adolescente , Angiografia , Criança , Pré-Escolar , Feminino , Seguimentos , França , Humanos , Lactente , Recém-Nascido , Icterícia/etiologia , Icterícia Neonatal/etiologia , Imageamento por Ressonância Magnética , Masculino , Gravidez , Remissão Espontânea , Tomografia Computadorizada por Raios X , Ultrassonografia , Ultrassonografia Pré-Natal
6.
Dev Biol (Basel) ; 135: 191-200, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23689897

RESUMO

Heartwater, caused by the Rickettsiales Ehrlichia ruminantium (ER), is a tropical tick-borne disease of wild and domestic ruminants, transmitted by Amblyomma ticks. It causes significant economic losses due to high mortality and the high cost of antibiotic treatment of affected animals, limiting herd productivity. It is present in sub-Saharan Africa, islands in the Indian Ocean and two Caribbean islands (Guadeloupe and Antigua) from where it threatens the American mainland due to risk of the spread of infected A. variegatum by migratory birds or by uncontrolled movement of animals. If an accidental introduction of a tick-free ER carrier animal occurs, autochthonous A. maculatum has proven to be a good experimental vector for heartwater. Modeling A. variegatum population dynamics has been developed, but further work is needed to predict favourable habitats and allow targeted surveillance. We overview here the advances in diagnostics, vaccines and epidemiology of heartwater and analyze the research gaps and needs to mitigate potential ER introduction and spread on the American mainland. Effective serologic ELISA tests allow prevalence studies, and several PCR-based diagnostic tests are currently available to detect ER in sick animals. However, the development of rapid assays, including multi-pathogen tests, would enhance the efficacy and cost-effectiveness of heartwater diagnosis. Several experimental vaccines (inactivated, attenuated and recombinant) are under development. Attenuated and inactivated vaccines are effective against homologous strains but their efficacy in the field is decreased due to broad antigenic diversity of ER. New molecular typing assays are now being used to study the genetic structure of ER populations worldwide, but the linking of genotyping to cross-protection is still not straightforward. Currently an inactivated vaccine would be the most appropriate vaccine for the American mainland due to its safety, the availability of a fully controlled bioprocess allowing ER mass production and the possibility to design "regional cocktail vaccines". This would require the selection and isolation of Caribbean ER strains supported by data of molecular epidemiology studies in this region. Development of an universal recombinant vaccine requires increased knowledge of ERbiology, including virulence mechanisms. Comparison of virulent and attenuated strains using"omic approaches" is on-going and will be crucial to understand these mechanisms and to develop improved vaccines.


Assuntos
Vacinas Bacterianas/imunologia , Hidropericárdio/prevenção & controle , Ruminantes , Animais , Controle de Doenças Transmissíveis , Ehrlichia ruminantium/patogenicidade , Saúde Global , Hidropericárdio/epidemiologia , Hidropericárdio/microbiologia , Reação em Cadeia da Polimerase/veterinária , Vigilância da População , Proteínas Recombinantes/imunologia , Testes Sorológicos/veterinária , Estados Unidos/epidemiologia , Vacinação , Vacinas Atenuadas , Virulência
7.
Prev Vet Med ; 110(3-4): 563-9, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23611065

RESUMO

Vaccination of domestic pets is an important component of rabies control and prevention in countries where the disease is maintained in a wildlife reservoir. In Grenada, vaccine coverage rates were low, despite extensive public education and advertising of government-sponsored vaccine clinics where rabies vaccine is administered to animals at no cost to animal owners. Information was needed on reasons for decreased dog owner participation in government-funded rabies vaccination clinics. A total of 120 dog owners from 6 different parishes were asked to complete a questionnaire assessing their currently held beliefs about rabies vaccination and perception of the risk posed by rabies. Over 70% of respondents believed that problems in the organization and management of clinic sites could allow for fighting between dogs or disease spread among dogs, while 35% of owners did not believe that they had the ability or adequate help to bring their dogs to the clinic sites. Recommendations for improving vaccine coverage rates included: improved scheduling of clinic sites and dates; increased biosecurity at clinic locations; focused advertising on the availability of home visits, particularly for aggressive dogs or dogs with visible skin-related diseases such as mange; and the recruitment of community volunteers to assist with bringing dogs to the clinic sites.


Assuntos
Doenças do Cão/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Raiva/veterinária , Vacinação/psicologia , Adolescente , Adulto , Idoso , Animais , Cães , Feminino , Granada , Humanos , Masculino , Pessoa de Meia-Idade , Raiva/prevenção & controle , Inquéritos e Questionários , Vacinação/veterinária , Adulto Jovem
8.
Rev Sci Tech ; 30(3): 725-31, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22435185

RESUMO

In 2009 CaribVET conducted a survey among Caribbean national Veterinary Services to assess perceptions of risk assessment and to identify the principal exotic diseases of concern in the region and their means of introduction. The results showed that the introduction of live animals was considered the most likely route of introduction of exotic animal pathogens, followed by the uncontrolled introduction of animal products by boat passengers. The results were used to define a regional strategy for assessing animal health risks that highlights the importance of within-region exchanges.


Assuntos
Controle de Doenças Transmissíveis/métodos , Doenças Transmissíveis Emergentes/veterinária , Doenças Transmissíveis/veterinária , Doenças Endêmicas/veterinária , Animais , Região do Caribe/epidemiologia , Controle de Doenças Transmissíveis/estatística & dados numéricos , Doenças Transmissíveis/epidemiologia , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/prevenção & controle , Doenças Endêmicas/prevenção & controle , Doenças Endêmicas/estatística & dados numéricos , Medição de Risco , Fatores de Risco , Inquéritos e Questionários
9.
Avian Dis ; 54(1 Suppl): 369-73, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20521662

RESUMO

The Caribbean region is considered to be at risk for avian influenza (AI) due to a large backyard poultry system, an important commercial poultry production system, the presence of migratory birds, and disparities in the surveillance systems. The Caribbean Animal Health Network (CaribVET) has developed tools to implement AI surveillance in the region with the goals to have 1) a regionally harmonized surveillance protocol and specific web pages for AI surveillance on www.caribvet.net, and 2) an active and passive surveillance for AI in domestic and wild birds. A diagnostic network for the Caribbean, including technology transfer and AI virus molecular diagnostic capability in Guadeloupe (real-time reverse transcription-polymerase chain reaction for the AI virus matrix gene), was developed. Between 2006 and 2009, 627 samples from four Caribbean countries were tested for three circumstances: importation purposes, following a clinical suspicion of AI, or through an active survey of wild birds (mainly waders) during the southward and northward migration periods in Guadeloupe. None of the samples tested were positive, suggesting a limited role of these species in the AI virus ecology in the Caribbean. Following low pathogenic H5N2 outbreaks in the Dominican Republic in 2007, a questionnaire was developed to collect data for a risk analysis of AI spread in the region through fighting cocks. The infection pathway of the Martinique commercial poultry sector by AI, through introduction of infected cocks, was designed, and recommendations were provided to the Caribbean Veterinary Services to improve cock movement control and biosecurity measures. The CaribVET and its organization allowed interaction between diagnostic and surveillance tools on the one hand and epidemiologic studies on the other, both of them developed in congruence with regional strategies. Together, these CaribVET activities contribute to strengthening surveillance of avian influenza virus (AIV) in the Caribbean region and may allow the development of research studies on both AI risk analysis and on AIV ecology.


Assuntos
Influenza Aviária/epidemiologia , Agricultura , Migração Animal , Animais , Animais Selvagens , Aves/classificação , Região do Caribe/epidemiologia , Comércio , Vigilância da População , Inquéritos e Questionários , Fatores de Tempo
10.
Transbound Emerg Dis ; 57(1-2): 11-4, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20537093

RESUMO

The Caribbean region is considered to be at risk for avian influenza (AI) because of predominance of the backyard poultry system, important commercial poultry production, migratory birds and disparities in the surveillance systems. The Caribbean animal health network (CaribVET) has developed tools to implement AI surveillance in the region: (i) a regionally harmonized surveillance protocol, (ii) specific web pages for AI surveillance on http://www.caribvet.net, and (iii) a diagnostic network for the Caribbean including AI virus molecular diagnostic capability in Guadeloupe and technology transfer. Altogether 303 samples from four Caribbean countries were tested between June 2006 and March 2009 by real time PCR either for importation purposes or following clinical suspicion. Following AI H5N2 outbreaks in the Dominican Republic in 2007, a questionnaire was developed to collect data for risk analysis of AI spread in the region through fighting cocks. The infection pathway of Martinique commercial poultry sector by AI through introduction of infected cocks was designed and recommendations were provided to the Caribbean veterinary services to improve fighting cock movement controls and biosecurity measures. Altogether, these CaribVET activities contribute to strengthen surveillance of AI in the Caribbean region and may allow the development of research studies on AI risk analysis.


Assuntos
Influenza Aviária/epidemiologia , Serviços de Informação , Medicina Veterinária/organização & administração , Agricultura , Migração Animal , Animais , Animais Selvagens , Aves , Região do Caribe , Comércio , Internet , Vigilância da População/métodos , Pesquisa , Inquéritos e Questionários , Fatores de Tempo
11.
Vet Parasitol ; 167(2-4): 327-35, 2010 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-19833441

RESUMO

Amblyomma variegatum, the Tropical Bont Tick (TBT), is the principal vector of heartwater and is associated with dermatophilosis, major causes of losses in animal production and mortality in Caribbean livestock. From 1995 to 2007, the Caribbean Amblyomma Programme (CAP) supported treatment and surveillance activities in 11 islands of the Eastern Caribbean with an initial objective of eradicating TBT. In addition to control activities, surveillance data were collected between 1997 and 2006 in a unique regional database. We report the analysis of the surveillance data from four islands (Nevis, St Kitts, St Lucia, and Barbados) where control and surveillance followed the initial protocol and where enough data were collected. We describe the evolution of TBT infestation levels and the efforts carried out throughout the surveillance period. Logistic regression identified factors associated with herds found infested with TBT. Overall, treatment programmes were associated with a decrease in proportion of TBT-infested farms. High surveillance efforts were carried out throughout the 1997-2007 period for all island of interest, but inadequate level of surveillance was observed in several quarters especially for St Kitts. Third quarter of the year, as indication of adult TBT seasonality on livestock, was significantly associated with the risk of detecting TBT in Nevis and St Kitts livestock farms. Also, presence of cattle in Nevis farms was shown associated with an increasing probability of farms being declared TBT-infested. Outcomes of these analyses provide basis for recommendations to improve future national and regional control and surveillance activities. This analysis demonstrates the usefulness of long term and adequate surveillance data for control programmes and identification of factors associated with risk of having infested herds.


Assuntos
Doenças dos Bovinos/epidemiologia , Infestações por Carrapato/epidemiologia , Carrapatos/fisiologia , Animais , Região do Caribe/epidemiologia , Bovinos , Doenças dos Bovinos/parasitologia , Inseticidas/farmacologia , Fatores de Risco , Infestações por Carrapato/parasitologia , Carrapatos/efeitos dos fármacos , Fatores de Tempo
12.
Prev Vet Med ; 92(1-2): 71-8, 2009 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-19664833

RESUMO

In Guadeloupe, West Nile virus (WNV) activity was first observed in equids in 2002, and a high seroprevalence was found in 2003. The objective of our study was to determine individual and environmental factors associated with the risk of WNV seropositivity during 2002-2003. Fieldwork was conducted to retrospectively determine the location of equids at the time of virus circulation and to collect information regarding environmental and individual variables. Sera were collected from 369 equids out of an estimated total population of less than 500. Thirty-four environmental and individual variables were investigated. Equids had a higher risk (p<0.001) for WNV seropositivity if they lived within the proximity "distance less than 1.5km" of marshes or swamp forests "a large freshwater formation behind mangroves" or if they remained outside after dusk. Equids living within the proximity of ouassous shrimp (Macrobrachium rosenbergii) basins or sugar cane fields had a lower risk (p<0.001) for WNV seropositivity. These results confirm that WNV circulation is more likely in the humid coastal areas of Guadeloupe. The identification of risk factors is useful for predicting future emergence sites of WNV in the archipelago and other Neotropical islands, and to better target sentinel surveillance in the region.


Assuntos
Equidae , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental/imunologia , Animais , Feminino , Guadalupe/epidemiologia , Cavalos , Masculino , Estudos Retrospectivos , Fatores de Risco , Estudos Soroepidemiológicos , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/imunologia
13.
Am J Med Genet A ; 146A(12): 1593-7, 2008 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-18470895

RESUMO

Spondylocarpotarsal synostosis syndrome (SCT) (OMIM 272460), originally thought to be a failure of normal spine segmentation, is characterized by progressive fusion of vertebras and associates unsegmented bars, scoliosis, short stature, carpal and tarsal synostosis. Cleft palate, sensorineural or mixed hearing loss, joint limitation, clinodactyly, and dental enamel hypoplasia are variable manifestations. Twenty-five patients have been reported. Thirteen affected individuals were siblings from six families and four of these families were consanguineous. In four of those families, Krakow et al. [Krakow et al. (2004) Nat Genet 36:405-410] found homozygosity or compound heterozygosity for mutations in the gene encoding FLNB. This confirmed autosomal recessive inheritance of the disorder. We report on two new patients (a mother and her son) representing the first case of autosomal dominant inheritance. These patients met the clinical and radiological criteria for SCT and did not present any features which could exclude this diagnosis. Molecular analysis failed to identify mutations in NOG and FLNB. SCT is therefore, genetically heterogeneous. Both dominant and autosomal recessive forms of inheritance should be considered during genetic counseling.


Assuntos
Genes Dominantes , Deformidades da Mão/diagnóstico por imagem , Deformidades da Mão/genética , Coluna Vertebral/anormalidades , Coluna Vertebral/diagnóstico por imagem , Sinostose/diagnóstico por imagem , Sinostose/genética , Ossos do Tarso/anormalidades , Ossos do Tarso/diagnóstico por imagem , Adulto , Criança , Proteínas Contráteis/genética , Feminino , Filaminas , Humanos , Masculino , Proteínas dos Microfilamentos/genética , Mutação , Linhagem , Fenótipo , Radiografia
14.
J Small Anim Pract ; 43(3): 115-23, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11916055

RESUMO

This study evaluated the accuracy of a new stereotactic CT-guided brain biopsy (SCTGBB) device on 23 client-owned dogs which presented with a brain lesion. Biopsy of the lesion was achieved in 95 per cent of cases. The target tissue was not sampled in one dog. Complications were observed in six dogs. Two dogs with highly vascularised brainstem tumours died after SCTGBB. Minor complications (slight variation in the neurological status) were observed in a further four cases. A diagnosis was reached in 16 dogs after cytological examination and in 21 dogs after histological evaluation. SCTGBB is an accurate diagnostic method for the diagnosis of brain lesions.


Assuntos
Neoplasias Encefálicas/veterinária , Doenças do Cão/patologia , Técnicas Estereotáxicas/veterinária , Animais , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Doenças do Cão/cirurgia , Cães , Feminino , Masculino , Tomografia Computadorizada por Raios X
15.
J Neurooncol ; 52(3): 205-15, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11519850

RESUMO

Diffuse invasion of the brain by tumor cells is a hallmark of human glioblastomas and a major cause for the poor prognosis of these tumors. This phenomenon is only partially reproduced by rodent models of gliomas that display a very high rate of proliferation and limited cell migration. We have analyzed the development of human glioblastoma cells (GL15) xenografted into the brain of immunosuppressed rats, in order to define the characteristics of tumor cell invasion. As identified by the specific immunolabeling of the tumor cells for the human HLA-ABC antigen, GL15 tumors reproduced the three types of intraparenchymal invasion observed in patients. First, a majority of multipolar tumor cells intermingled rapidly and profusely with host neural cells in the margin of the injection site. This progressively enlarging area was principally responsible for the tumor growth over time. Second, in the gray matter, columns of thin bipolar tumor cells aligned along capillary walls. Third, in the white matter, elongated bipolar isolated tumor cells were observed scattered between axonal fibers. The maximum migration distances along white matter fibers remained significantly higher than the maximum migration distances along blood vessels, up to two months after injection. Development of the tumor was associated with a significant increase of vascularization in the area of tumor spread. Xenografting of human GL15 glioblastoma cells into the immunosuppressed rat brain allowed to differentiate between the three classical types of invasion identified in the clinic, to quantify precisely the distances of migration, and to evaluate cell morphology for each of these routes. The present results support the existence of host/tumor cells interactions with specific characteristics for each type of invasion.


Assuntos
Neoplasias Encefálicas/patologia , Transplante de Tecido Encefálico , Encéfalo/patologia , Glioblastoma/patologia , Invasividade Neoplásica/patologia , Células-Tronco Neoplásicas/transplante , Transplante Heterólogo/patologia , Animais , Antígenos de Neoplasias/análise , Biomarcadores , Neoplasias Encefálicas/irrigação sanguínea , Capilares/patologia , Movimento Celular , Ciclosporina/toxicidade , Glioblastoma/irrigação sanguínea , Antígenos HLA/análise , Humanos , Hospedeiro Imunocomprometido , Imunossupressores/toxicidade , Masculino , Pessoa de Meia-Idade , Transplante de Neoplasias , Células-Tronco Neoplásicas/patologia , Neovascularização Patológica/patologia , Ratos , Ratos Sprague-Dawley , Células Tumorais Cultivadas/patologia , Células Tumorais Cultivadas/transplante
16.
Neuroreport ; 11(2): 389-93, 2000 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-10674492

RESUMO

Glioblastomas are particularly resistant to classical antitumor treatments. Retinoids, which proved effective in the treatment of promyelocytic leukemia, have been used for clinical assays on glioma tumors with only moderate effects; however in some cases they were active in combination with another therapy. These observations prompted us to analyse the efficacy of combining retinoic acid (RA) with a cytokine on a clonal human glioma cell line. On GL-15 cells, RA and tumor necrosis factor alpha (TNFalpha) both reduced the glial fibrillary acidic protein level and DNA synthesis and induced apoptotic pathways, but they were significantly more effective when used together. The up-regulation of the p55 TNF receptors observed during RA exposure might explain this cooperative effect.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Glioblastoma/tratamento farmacológico , Antígenos CD/genética , Antígenos CD/metabolismo , Apoptose , Bucladesina/farmacologia , Tamanho Celular/efeitos dos fármacos , Meios de Cultura Livres de Soro/farmacologia , DNA/biossíntese , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Imunofluorescência , Proteína Glial Fibrilar Ácida/biossíntese , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Ligação Proteica/efeitos dos fármacos , RNA Mensageiro/metabolismo , Receptores do Fator de Necrose Tumoral/genética , Receptores do Fator de Necrose Tumoral/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral , Receptores Tipo II do Fator de Necrose Tumoral , Acetato de Tetradecanoilforbol/farmacologia , Timidina/metabolismo , Tretinoína/administração & dosagem , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/administração & dosagem , Regulação para Cima/efeitos dos fármacos
17.
Vet Parasitol ; 86(2): 95-103, 1999 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-10496693

RESUMO

African animal trypanosomoses constitute the most important vector-borne cattle diseases in sub-Saharan Africa. Generally it is considered that there is a great lack of accurate tools for the diagnosis of the disease. During a trypanosomosis survey in the agro-pastoral zone of Sideradougou, Burkina Faso, 1036 cattle were examined for trypanosomes using microscopy. The PCR was applied on a subset of 260 buffy-coat samples using primers specific for Trypanosoma congolense savannah and riverine-forest groups, T. vivax, and T. brucei. Parasitological examination and the molecular technique were compared, showing a better efficiency of the latter. In the near future, the PCR is likely to become an efficient tool to estimate the prevalence of African trypanosomoses in affected areas.


Assuntos
Trypanosoma/isolamento & purificação , Tripanossomíase Bovina/diagnóstico , Animais , Burkina Faso/epidemiologia , Bovinos , Primers do DNA/química , DNA de Protozoário/química , Eletroforese em Gel de Ágar/veterinária , Hematócrito/veterinária , Microscopia/veterinária , Reação em Cadeia da Polimerase/veterinária , Prevalência , Trypanosoma/classificação , Trypanosoma/genética , Trypanosoma brucei brucei/genética , Trypanosoma brucei brucei/isolamento & purificação , Trypanosoma congolense/genética , Trypanosoma congolense/isolamento & purificação , Trypanosoma vivax/genética , Trypanosoma vivax/isolamento & purificação , Tripanossomíase Africana/diagnóstico , Tripanossomíase Africana/epidemiologia , Tripanossomíase Africana/veterinária , Tripanossomíase Bovina/epidemiologia
18.
Mem Inst Oswaldo Cruz ; 94(2): 245-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10224537

RESUMO

The epidemiology of animal trypanosomosis around Bobo-Dioulasso (Burkina Faso, West Africa) benefited a lot in the last years from the progress of molecular tools. The two most used molecular techniques were the polymerase chain reaction for the diagnosis of the disease in cattle and the characterization of the trypanosomes in the host and the vector on one hand, and the microsatellite DNA polymorphism in tsetse flies to study the intraspecific genetic variability of the vector on the other hand. The results obtained in the Sideradougou area during a recent two year survey with these techniques, associated with many other georeferenced informations concerning vector and cattle distribution, natural environment, landuse, ground occupation, livestock management, were combined in a Geographical Information System. This new approach of a complex pathogenic system led to a better evaluation of the risk of trypanosome transmission.


Assuntos
Tripanossomíase Africana/veterinária , Tripanossomíase Bovina/epidemiologia , África Ocidental/epidemiologia , Animais , Bovinos , Marcadores Genéticos , Repetições de Microssatélites , Fatores de Risco , Tripanossomíase Africana/diagnóstico , Tripanossomíase Africana/epidemiologia , Tripanossomíase Africana/genética , Tripanossomíase Bovina/diagnóstico , Tripanossomíase Bovina/genética
19.
Acta Trop ; 72(1): 65-77, 1999 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-9924962

RESUMO

The polymerase chain reaction was used to characterize the trypanosomes infecting Glossina morsitans submorsitans and G. tachinoides in the game ranch of Nazinga, Burkina Faso, situated near an agropastoral zone. Dissection of 435 tsetse flies, and PCR analysis of 166 infected flies were conducted to assess the epidemiological situation. Trypanosomes of the Nannomonas subgenus were the most abundant in the two tsetse species (80.4% and 73.7% of identified infections in G. m. submorsitans and G. tachinoides respectively). T. vivax and T. brucei infection rates were comparable between the two tsetse species. Mature infection pattern identified by PCR differed from overall infections, mainly because T. simiae infections did not mature, whereas T. vivax represented the predominant taxon. Parasitological and PCR results showed some discrepancies; possibly some typical Duttonella strains could not be recognized by the sets of primers used. The technologies used in this work helped to determine the high trypanosomosis risk in this area.


Assuntos
Insetos Vetores/parasitologia , Reação em Cadeia da Polimerase , Trypanosoma/classificação , Trypanosoma/isolamento & purificação , Moscas Tsé-Tsé/parasitologia , Animais , Animais Selvagens , Sangue , Burkina Faso , Comportamento Alimentar , Trypanosoma/genética , Trypanosoma brucei brucei/classificação , Trypanosoma brucei brucei/isolamento & purificação , Trypanosoma vivax/classificação , Trypanosoma vivax/isolamento & purificação , Tripanossomíase Africana/transmissão , Tripanossomíase Africana/veterinária , Moscas Tsé-Tsé/fisiologia
20.
Mol Ecol ; 7(7): 897-904, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9691491

RESUMO

A multidisciplinary work was undertaken in the agropastoral zone of Sidéradougou, Burkina Faso to try to elucidate the key factors determining the presence of tsetse flies. In this study the PCR was used to characterize trypanosomes infecting the vector (Glossina tachinoides and Glossina palpalis gambiensis) and the host, i.e. cattle. A 2-year survey involved dissecting 2211 tsetse of the two Glossina species. A total of 298 parasitologically infected tsetse were analysed by PCR. Trypanosoma vivax was the most frequently identified trypanosome followed by the savannah type of T. congolense and, to a lesser extent, the riverine forest type of T. congolense, and by T brucei. No cases of T. simiae were found. From the 107 identified infections in cattle, the taxa were the same, but T. congolense savannah type was more frequent, whereas T. vivax and T. congolense riverine forest types were found less frequently. A correlation was found between midgut infection rates of tsetse, nonidentified infections and reptile bloodmeals. These rates were higher in G.p. gambiensis, and in the western part of the study area. T. vivax infections were related to cattle bloodmeals, and were more frequent in G. tachinoides and in the eastern study area. The PCR results combined with bloodmeal analysis helped us to establish the relationships between the vector and the host, to assess the trypanosome challenge in the two parts of the area, to elucidate the differences between the two types of T. congolense, and to suspect that most midgut infections were originating from reptilian trypanosomes.


Assuntos
Insetos Vetores/parasitologia , Trypanosoma/isolamento & purificação , Tripanossomíase Bovina/epidemiologia , Moscas Tsé-Tsé/parasitologia , Animais , Burkina Faso/epidemiologia , Bovinos , DNA de Protozoário/análise , Sistema Digestório/parasitologia , Interações Hospedeiro-Parasita , Epidemiologia Molecular , Reação em Cadeia da Polimerase , Trypanosoma/classificação , Trypanosoma/genética , Tripanossomíase Africana/epidemiologia , Tripanossomíase Africana/parasitologia , Tripanossomíase Africana/veterinária , Tripanossomíase Bovina/parasitologia
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