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1.
J Appl Stat ; 49(5): 1235-1251, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35707505

RESUMEN

The vote shares by party on a given subdivision of a territory form a vector called composition (mathematically, a vector belonging to a simplex). It is interesting to model these shares and study the impact of the characteristics of the territorial units on the outcome of the elections. In the political economy literature, few regression models are adapted to the case of more than two political parties. In the statistical literature, there are regression models adapted to share vectors including Compositional Data (CoDa) models, but also Dirichlet models, and others. Our goal is to discuss and illustrate the use CoDa regression models for political economy models for more than two parties. The models are fitted on French electoral data of the 2015 departmental elections.

2.
J Virol Methods ; 289: 114060, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33359614

RESUMEN

BACKGROUND: This study aimed to compare four anti-SARS-CoV-2 immunoassays in populations presenting different clinical severity levels. METHODS: Three populations were included: "severe-to-critical" ICU-hospitalized patients (n = 18), "mild-to-moderate" hospitalized patients (n = 16) and non-hospitalized symptomatic patients (n = 24). Four commercial immunoassays were analyzed and validated: anti-IgG ARCHITECT® (Abbott), anti-Total antibodies (Ab) VITROS® (Ortho Clinical Diagnostics), anti-IgG NovaLisa® (NovaTec Immundiagnostica) and Healgen® IgM and IgG (Zhejiang Orient Gene Biotech). Sensitivities were evaluated according to days post-symptoms onset (pso). Specificities were evaluated on SARS-CoV-2-negative control sera collected before January 2020. RESULTS: A majority of severe-to-critically ill patients showed detectable Ab already at day 14 and sensitivities reached 100 % after 22 days pso. For patients with "mild-to-moderate" illness, sensitivities increased by at least 5-fold from day 0 to day 14 pso. Non-hospitalized symptomatic individuals already seroconverted at day 14 days pso with 100 % sensitivities for Total Ab VITROS®. Specificities were evaluated at 97 % for ARCHITECT® and NovaLisa®, 98 % for VITROS® and at 94 % for Healgen® combined IgM and IgG. Five "severe-to-critically" ill patients presented high positive Ab levels for at least 16 weeks pso. CONCLUSION: The Ab levels and the evaluated sensitivities, representing the true positive rate, increased overtime and were related to the COVID-19 severity. Automated Total Ab immunoassay showed better sensitivities and specificity for immunological surveillance and vaccine evaluation.


Asunto(s)
Anticuerpos Antivirales/sangre , Prueba Serológica para COVID-19/métodos , COVID-19/diagnóstico , Inmunoensayo/métodos , Humanos , SARS-CoV-2/inmunología , SARS-CoV-2/aislamiento & purificación , Sensibilidad y Especificidad
3.
BMC Womens Health ; 18(1): 140, 2018 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-30115038

RESUMEN

BACKGROUND: Violence against women remains an important issue of inequality in African societies, with several consequences to health, social and economic status. This study aims to identify the factors related to the perception of intimate partner violence in Benin. METHODS: Data on intimate partner violence was collected by conducting live interviews, and from the Benin Demographic and Health Survey 2012. The dependent variable was acceptance of intimate partner violence. The independent variables were socio-demographic features such as age, level of education, matrimonial status, ethnicity, religion, place of residence and the index of economic well-being. Logistic regressions were performed and odds ratios (OR) with a confidence interval of 95% (CI95%) were estimated. RESULTS: Among the 21,574 people who answered the questions relating to violence against women by an intimate partner, the prevalence of acceptance of intimate partner violence was 15.77%. Ethnicity, level of education, administrative department of residence, religion, and socio-economic quintile were factors associated with the respondents' acceptance of violence against women by an intimate partner. CONCLUSION: Acceptance of intimate partner violence could be a major obstacle to the success of some health programs. There is a need to break the norms that support the vulnerability of women in Beninese society.


Asunto(s)
Encuestas Epidemiológicas , Violencia de Pareja/psicología , Violencia de Pareja/estadística & datos numéricos , Adolescente , Adulto , Benin , Femenino , Humanos , Relaciones Interpersonales , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Prevalencia , Factores Socioeconómicos , Adulto Joven
4.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-758779

RESUMEN

Brucellosis is an emerging infectious disease affecting humans and animals. In this study, we investigated the in vitro and in vivo effects of tannic acid (TA) against Brucella abortus infection. After infection, F-actin polymerization and mitogen-activated protein kinases (MAPKs) (ERK 1/2 and p38α) phosphorylation were reduced in TA-treated cells compared with that in control cells. The mice were infected via an intraperitoneal route and were orally given TA or phosphate-buffered saline for 14 days. Spleen weights of the TA-treated and control mice were not different; however, splenic proliferation of B. abortus was significantly reduced in the TA-treated group. Immune response analysis showed that, compared with the control group, non-infected TA-treated mice displayed increased levels of interferon-γ (IFN-γ), monocyte chemoattractant protein-1 (MCP-1), and interleukin-10 at 3 days post-infection and a further increase in IFN-γ and MCP-1 at 14 days post-infection. In contrast, compared with the control group, infected TA-treated mice displayed elevated levels of IFN-γ at 3 days post-infection, which continued to increase at 14 days post-infection, as was also observed for tumor necrosis factor. Taken together, the results showing TA activation of cytokine production and inhibition of bacterial proliferation in the host highlight a potential use of TA treatment in the control of Brucella infection.


Asunto(s)
Animales , Humanos , Ratones , Actinas , Brucella abortus , Brucella , Brucelosis , Quimiocina CCL2 , Enfermedades Transmisibles Emergentes , Citocinas , Técnicas In Vitro , Interleucina-10 , Proteínas Quinasas Activadas por Mitógenos , Fosforilación , Polimerizacion , Polímeros , Bazo , Taninos , Factor de Necrosis Tumoral alfa , Pesos y Medidas
5.
Phys Rev Lett ; 115(18): 187402, 2015 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-26565495

RESUMEN

We report an anomalous wide broadening of the emission spectra of an electronic excitation confined in a two-dimensional potential. We attribute these results to an extremely fast radiative decay rate associated with superradiant emission from the ensemble of confined electrons. Lifetimes extracted from the spectra are below 100 fs and, thus, 6 orders of magnitude faster than for single particle transitions at similar wavelength. Moreover, the spontaneous emission rate increases with the electronic density, as expected for superradiant emission. The data, all taken at 300 K, are in excellent agreement with our theoretical model, which takes into account dipole-dipole Coulomb interaction between electronic excitations. Our experimental results demonstrate that the interaction with infrared light, which is usually considered a weak perturbation, can be a very efficient relaxation mechanism for collective electronic excitations in solids.

6.
Arch Public Health ; 72(1): 25, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25114792

RESUMEN

BACKGROUND: Routine health information systems (RHIS) are crucial to the acquisition of data for health sector planning. In developing countries, the insufficient quality of the data produced by these systems limits their usefulness in regards to decision-making. The aim of this study was to identify the factors associated with poor data quality in the RHIS in Benin. METHODS: This cross-sectional descriptive and analytical study included health workers who were responsible for data collection in public and private health centers. The technique and tools used were an interview with a self-administered questionnaire. The dependent variable was the quality of the data. The independent variables were socio-demographic and work-related characteristics, personal and work-related resources, and the perception of the technical factors. The quality of the data was assessed using the Lot Quality Assurance Sampling method. We used survival analysis with univariate proportional hazards (PH) Cox models to derive hazards ratios (HR) and their 95% confidence intervals (95% CI). Focus group data were evaluated with a content analysis. RESULTS: A significant link was found between data quality and level of responsibility (p = 0.011), sector of employment (p = 0.007), RHIS training (p = 0.026), level of work engagement (p < 0.001), and the level of perceived self-efficacy (p = 0.03). The focus groups confirmed a positive relationship with organizational factors such as the availability of resources, supervision, and the perceived complexity of the technical factors. CONCLUSION: This exploratory study identified several factors associated with the quality of the data in the RHIS in Benin. The results could provide strategic decision support in improving the system's performance.

7.
J Biomed Mater Res A ; 102(9): 2942-51, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24123800

RESUMEN

The aim of this study was to develop an antiseptic and blue dyed polyester (PET) vascular graft in order to reach two distinct properties: (i) the prevention of postoperative infections, (ii) the improvement of the graft compatibility with the coelioscopy surgical technique. This work consisted of dyeing a vascular prosthesis with methylene blue (MB) which is known as a cationic dye with antiseptic properties. Therefore, the functionalization of the PET fibers of the prosthesis with a cyclodextrin-citric acid polymer (PolyCD) was achieved in order to improve its sorption capacity. The NMR experiments demonstrated that a 1:2 complex occurred between hydroxypropyl ß-cyclodextrin (HP-ßCD) and MB. Kinetic and sorption isotherm studies showed that an impregnation of the polyCD modified prosthesis (PET-CD) in a 1 g L(-1) of MB solution for 150 min was sufficient to reach the saturation of the device. Results proved that the adsorption mechanism followed the Langmuir model and a maximum of 20 mg g(-1) of MB on the graft. A sustained release of MB in batch tests was observed in PBS and in vitro microbiological assays displayed a prolongation of the bactericidal effect of PET-CD whose extent varied with the amount of MB preliminarily adsorbed onto the PET-CD.


Asunto(s)
Antibacterianos/administración & dosificación , Prótesis Vascular/microbiología , Celulosa/química , Ciclodextrinas/química , Azul de Metileno/administración & dosificación , Poliésteres/química , Antibacterianos/farmacología , Línea Celular , Humanos , Azul de Metileno/farmacología , Infecciones Estafilocócicas/prevención & control , Staphylococcus epidermidis/efectos de los fármacos
8.
Acta Biomater ; 7(8): 3141-9, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21569872

RESUMEN

The aim of this work was to develop a polypropylene (PP) artificial abdominal wall implant for the prolonged release of ciprofloxacin (CFX). This sustained release effect was obtained by functionalization of the textile mesh with citric acid and hydroxypropyl-γ-cyclodextrin (HPγCD) or maltodextrin (MD). In both cases the textile finishing reaction yielded a cyclo- or malto-dextrin crosslinked polymer coating the fibers. The modified supports were characterized by thermogravimetric analysis (TGA), differential scanning calorimetry and scanning electron microscopy. The sorption capacities and the kinetics of CFX release were studied by batch tests coupled with spectrophotometric assays. Microbiological assays were carried out on Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli, while proliferation and viability tests used fibroblasts. The main results were as follows. (i) Due to the differences between the range of temperature of thermal degradation of the (cyclo)dextrins polymers and of the PP fibers TGA was a reliable method for quantifying the degree of functionalization of the textiles. (ii) Both modified supports showed improved sorption/desorption capacities for CFX, compared with the virgin mesh. The HPγCD-finished support showed an increased sorption capacity and a lower release rate of CFX compared with the MD modified support. (iii) Microbiological assays confirmed the latter result, with greater sustained antibacterial activity of the HPγCD treated support. These experiments have demonstrated the role of the cyclodextrin cavity in interactions with CFX: the antibiotic was not only adsorbed via hydrogen and acid-base interactions with the polyCTR-HPγCD network, but also via host-guest complexation. (iv) Biological tests revealed a slight decrease in fibroblast proliferation after 6 days on the modified supports, but cell viability tests showed that this was not due to toxicity of the (cyclo)dextrin polymer coatings.


Asunto(s)
Pared Abdominal/fisiología , Ciprofloxacina/farmacología , Ciclodextrinas/química , Implantes Experimentales , Polipropilenos/química , Polisacáridos/química , Adsorción/efectos de los fármacos , Animales , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Rastreo Diferencial de Calorimetría , Adhesión Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Cristalización , Preparaciones de Acción Retardada , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Implantes Experimentales/microbiología , Ratones , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Células 3T3 NIH , Termogravimetría , Factores de Tiempo , Temperatura de Transición/efectos de los fármacos
9.
Eur J Clin Microbiol Infect Dis ; 30(2): 209-18, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20936316

RESUMEN

For the epidemiological monitoring and clinical case management of leishmaniasis, determination of the causative Leishmania species gains importance. Current assays for the Old World often suffer from drawbacks in terms of validation on a geographically representative sample set and the ability to recognize all species complexes. We want to contribute to standardized species typing for Old World leishmaniasis. We determined the ribosomal DNA internal transcribed spacer 1 sequence of 24 strains or isolates, and validated four species-specific polymerase chain reactions (PCRs) amplifying this target. They discriminate L. aethiopica, L. tropica, L. major, and the L. donovani complex, use the same cycling conditions, and include an internal amplification control. Our PCRs amplify 0.1 pg of Leishmania DNA, while being 100% specific for species identification on an extensive panel of geographically representative strains and isolates. Similar results were obtained in an endemic reference laboratory in Kenya. Species could also be identified in clinical specimens. The presented PCRs require only agarose gel detection, and have several other advantages over many existing assays. We outline potential problems, suggest concrete solutions for transferring the technique to other settings, and deliver the proof-of-principle for analyzing clinical samples.


Asunto(s)
Leishmania/clasificación , Leishmania/aislamiento & purificación , Leishmaniasis/diagnóstico , Parasitología/métodos , Reacción en Cadena de la Polimerasa/métodos , Animales , Cartilla de ADN/genética , ADN Protozoario/genética , ADN Espaciador Ribosómico/genética , Perros , Electroforesis en Gel de Agar , Humanos , Leishmania/genética , Leishmaniasis/parasitología , Sensibilidad y Especificidad
10.
Gynecol Obstet Fertil ; 38(10): 600-6, 2010 Oct.
Artículo en Francés | MEDLINE | ID: mdl-20870442

RESUMEN

In order to decrease the psychological impact and the mutilating feeling of surgical treatments of the breast cancer when the mastectomy is indicated, authors described and propose the nipple sparing mastectomy (NSM). The only opposable criticism would be the increase of recurrence rate. The study of the recent literature allows us to make a inventory of fixtures concerning this evolution of the surgical practices whether on a technical, oncological, plastic or psychological plan. This technique is not validated in France and adjuvent therapies as the radiotherapy of the nipple are not validated yet. It seems that the NSM is a safe practice from the carcinologic point of view, while having a positive psychological impact in terms of disease and treatment acceptance. The technique seems possible after an information and selection of the patients and with a respect for technical rules (frozen section, peroperative evaluation of the nipple vitality).


Asunto(s)
Neoplasias de la Mama/cirugía , Mastectomía/métodos , Pezones , Femenino , Francia , Humanos , Mastectomía/psicología , Recurrencia Local de Neoplasia/epidemiología , Radioterapia Adyuvante , Factores de Riesgo , Biopsia del Ganglio Linfático Centinela
12.
J Hosp Infect ; 71(3): 234-8, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19162371

RESUMEN

Though brushes are no longer used on the hands and forearms during the surgical scrub, they are still widely used on the nails. The aim of this study was to determine whether nail picks and nail brushes are effective in providing additional decontamination during a surgical hand scrub. A total of 164 operating department staff were randomised to undertake one of the following three surgical hand-scrub protocols: chlorhexidine only; chlorhexidine and a nail pick; or chlorhexidine and a nail brush. Bacterial hand sampling was conducted before and 1h after scrubbing using a modified version of the glove juice method. No statistically significant differences in bacterial numbers were found between any two of the three intervention groups. Nail brushes and nail picks used during surgical hand scrubs do not decrease bacterial numbers and are unnecessary.


Asunto(s)
Desinfección de las Manos/métodos , Control de Infecciones/instrumentación , Uñas , Procedimientos Quirúrgicos Operativos , Administración Cutánea , Antiinfecciosos Locales/administración & dosificación , Clorhexidina/administración & dosificación , Recuento de Colonia Microbiana , Femenino , Humanos , Masculino
13.
Mol Biochem Parasitol ; 160(2): 167-70, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18501978

RESUMEN

The applications of highly specific and sensitive molecular techniques based on polymerase chain reaction (PCR) have constituted a valuable tool for the diagnosis of schistosomiasis and also for the detection of schistosome infections in the snail intermediate hosts. The common method of detecting PCR amplicons is gel electrophoresis in the presence of ethidium bromide, a carcinogen, which is followed by UV transillumination. Other methods, which are available for detecting PCR products, are real-time PCR, PCR-enzyme-linked immunosorbent assay (PCR-ELIZA) and mass spectrometry but they are cumbersome while they are sometimes complex and expensive. Therefore, a simple method of PCR product detection would be a welcome idea and a most valuable tool particularly in disease endemic countries with limited research facilities and resources. In this study, we applied a simple and rapid method for the detection of Schistosoma haematobium and Schistosoma mansoni PCR amplified DNA products using oligochromatographic (OC) dipstick. The amplicons are visualized by hybridization with a gold conjugated probe, while a control for the chromatographic migration is incorporated in the assay. The lower detection limit observed was 10fg of genomic DNA from each of the two species, while the dipstick was also specific for each of the species used in this study.


Asunto(s)
ADN de Helmintos/análisis , Técnicas de Diagnóstico Molecular/métodos , Parasitología/métodos , Reacción en Cadena de la Polimerasa , Schistosoma haematobium/aislamiento & purificación , Schistosoma mansoni/aislamiento & purificación , Esquistosomiasis/diagnóstico , Animales , ADN de Helmintos/genética , Técnicas de Diagnóstico Molecular/economía , Parasitología/economía , Sensibilidad y Especificidad
14.
Acta Biomater ; 4(5): 1392-400, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18378201

RESUMEN

This study describes the use of cyclodextrins (CDs) as a finishing agent of polyamide (PA) fibers used in order to obtain inguinal meshes with improved antibiotic delivery properties. The finishing process involved polymerization between citric acid and CDs, which yielded a cross-linked polymer that physically adhered to the surface of PA fibers. This permanent functionalization was characterized by evaluating the damping property with a polar liquid (glycerol) via the drop contact angle method for various rates of modification of the fabrics. The biological and microbiological effects of the PA, which were functionalized with hydroxypropylated derivate of gamma-CD (HP-gamma-CDs) and charged with ciprofloxacin (CFX), were evaluated by cell culture assays. We observed a good adhesion and proliferation of fibroblastic cells (NIH3T3) after 3 and 6 days and no detectable toxicity of the modified substrate. The in vitro antibacterial activity of the HP-gamma-CD grafted PA fabrics charged with CFX against the bacteria Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli was greatly superior to that of the virgin sample within a 24h batch experiment in human blood plasma medium. In conclusion, these results from our study offer an insight into the efficient performance of CDs as drug delivery systems for multiple applications in the fields of biomaterials and medical textiles.


Asunto(s)
Ciclodextrinas/administración & dosificación , Implantes de Medicamentos/administración & dosificación , Implantes de Medicamentos/química , Bacterias Gramnegativas/efectos de los fármacos , Conducto Inguinal , Nylons/química , Mallas Quirúrgicas , Antibacterianos/administración & dosificación , Adhesión Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Bacterias Gramnegativas/citología , Humanos , Ensayo de Materiales
15.
Acta Crystallogr D Biol Crystallogr ; 62(Pt 10): 1184-95, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17001095

RESUMEN

SPINE (Structural Proteomics In Europe) was established in 2002 as an integrated research project to develop new methods and technologies for high-throughput structural biology. Development areas were broken down into workpackages and this article gives an overview of ongoing activity in the bioinformatics workpackage. Developments cover target selection, target registration, wet and dry laboratory data management and structure annotation as they pertain to high-throughput studies. Some individual projects and developments are discussed in detail, while those that are covered elsewhere in this issue are treated more briefly. In particular, this overview focuses on the infrastructure of the software that allows the experimentalist to move projects through different areas that are crucial to high-throughput studies, leading to the collation of large data sets which are managed and eventually archived and/or deposited.


Asunto(s)
Biología Computacional/estadística & datos numéricos , Proteómica/estadística & datos numéricos , Cristalización , Interpretación Estadística de Datos , Gestión de la Información , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Programas Informáticos
16.
J Clin Microbiol ; 44(8): 2884-9, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16891507

RESUMEN

Human African trypanosomiasis (HAT) or sleeping sickness is a neglected disease that affects poor rural populations across sub-Saharan Africa. Confirmation of diagnosis is based on detection of parasites in either blood or lymph by microscopy. Here we present the development and the first-phase evaluation of a simple and rapid test (HAT-PCR-OC [human African trypanosomiasis-PCR-oligochromatography]) for detection of amplified Trypanosoma brucei DNA. PCR products are visualized on a dipstick through hybridization with a gold-conjugated probe (oligochromatography). Visualization is straightforward and takes only 5 min. Controls both for the PCR and for DNA migration are incorporated into the assay. The lower detection limit of the test is 5 fg of pure T. brucei DNA. One parasite in 180 microl of blood is still detectable. Sensitivity and specificity for T. brucei were calculated at 100% when tested on blood samples from 26 confirmed sleeping sickness patients, 18 negative controls (nonendemic region), and 50 negative control blood samples from an endemic region. HAT-PCR-OC is a promising new tool for diagnosis of sleeping sickness in laboratory settings, and the diagnostic format described here may have wider application for other infectious diseases.


Asunto(s)
ADN Protozoario/análisis , Técnicas de Diagnóstico Molecular , Hibridación de Ácido Nucleico/métodos , Reacción en Cadena de la Polimerasa/métodos , Trypanosoma brucei brucei/aislamiento & purificación , Tripanosomiasis Africana/diagnóstico , Animales , Secuencia de Bases , Sangre/parasitología , ADN Protozoario/genética , ADN Protozoario/aislamiento & purificación , Humanos , Datos de Secuencia Molecular , Estándares de Referencia , Sensibilidad y Especificidad , Trypanosoma brucei brucei/genética
17.
Parasitology ; 131(Pt 3): 321-9, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16178353

RESUMEN

The protozoan parasite Leishmania belongs to the most ancient eukaryotic lineages and this is reflected in several distinctive biological features, such as eukaryotic polycistronic transcription and RNA trans-splicing. The disclosure of this organism's unusual characteristics leads to a better understanding of the origin and nature of fundamental biological processes in eukaryotes. Here we report another unusual phenomenon as we demonstrate that precursor ribosomal RNA can be extensively polyadenylated during post-transcriptional processingt. Furthermore, we demonstrate that the degree of precursor rRNA polyadenylation is variable in different strains and in the different life-stages of a strain.


Asunto(s)
Leishmania/genética , Leishmania/metabolismo , Poliadenilación/fisiología , ARN Protozoario/metabolismo , ARN Ribosómico/metabolismo , Regiones no Traducidas 3' , Animales , Secuencia de Bases , Datos de Secuencia Molecular , Proteínas Protozoarias/biosíntesis , ARN Protozoario/química , ARN Ribosómico/química , Alineación de Secuencia
18.
Parasitology ; 131(Pt 2): 207-14, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16145937

RESUMEN

The major surface protease (msp or gp63) of Leishmania plays a major role in the host-parasite interaction. We analysed here the structure of the msp gene locus in Leishmania (Viannia) braziliensis and compared it to results obtained in other species. Physical mapping of cosmid contigs revealed a minimum of 37 genes per haploid genome and at least 8 different msp gene families. Within the same organism, these genes showed a nucleotide sequence varying in certain stretches from 3 to 34%, and a mosaic structure. From an evolutionary point of view, major differences were observed between subgenera Viannia and Leishmania, both in terms of msp gene number and sequence. Within subgenus Viannia, phenetic analysis revealed three clusters in which sequence variants of L. (Viannia) braziliensis and L. (Viannia) guyanensis were interspersed. Functional implications of our results were explored from predicted L. (Viannia) braziliensis protein sequences: regions encoding the msp catalytic site showed a conserved sequence, while regions encoding surface domains possibly involved in the host-parasite interaction (macrophage adhesion sites and immunodominant B-cell and T-cell epitopes) were variable. We speculate that this would be an adaptive strategy of the parasite.


Asunto(s)
Evolución Molecular , Leishmania braziliensis/genética , Proteínas de la Membrana/genética , Metaloendopeptidasas/genética , Proteínas Protozoarias/genética , Animales , Variación Genética , Filogenia , Mapeo Físico de Cromosoma
19.
Vet Microbiol ; 90(1-4): 317-28, 2002 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-12414152

RESUMEN

Although Brucella is responsible for one of the major worldwide zoonosis, our understanding of its pathogenesis remains in its infancy. In this paper, we summarize some of the research in progress in our laboratory that we think could contribute to a better understanding of the Brucella molecular virulence mechanisms and their regulation.


Asunto(s)
Brucella/fisiología , Brucella/patogenicidad , Animales , Brucella/citología , Brucelosis/microbiología , Brucelosis/veterinaria , Comunicación Celular , Ciclo Celular/genética , Flagelos/genética , Humanos , Mediciones Luminiscentes , Vibrio/patogenicidad , Vibrio/fisiología , Zoonosis/epidemiología
20.
Scand J Clin Lab Invest ; 61(2): 131-7, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11347980

RESUMEN

Pre-eclampsia is a serious multi-system disorder with general endothelial disease, often with a component of hepatic dysfunction. The pathogenesis of preeclampsia is not fully understood, and no specific diagnostic tests are available for early and reliable diagnosis, or for monitoring of the disease process. Hyaluronan is an extracellular matrix polysaccharide present at low concentrations in plasma. Normally, it is rapidly eliminated from the blood by the liver. Increased concentrations of circulating hyaluronan are seen in conditions with impaired hepatic function such as liver cirrhosis, and hyaluronan concentrations have previously been used to evaluate hepatic function in other diseases. In the present study, 11 pregnant women admitted to the intensive care unit with severe pre-eclampsia or eclampsia were studied. As control 31 healthy pregnant women, 18 undergoing vaginal delivery and 13 caesarean section, were included. Plasma hyaluronan was measured before and after delivery. Increased concentrations of plasma hyaluronan were found in the pre-eclampsia group both before (171 (75-586) microg/L (p<0.01)) and after delivery (215 (124-768) microg/L (p<0.001)) (median and inter-quartile range), as compared to both caesarean section (13 (7-28) microg/L before and 28 (18-48) microg/L after delivery) and vaginal delivery healthy controls (12 (8-24) microg/L before and 30 (13 63) microg/L after delivery). In the control groups, a small increase in plasma hyaluronan was seen after delivery, after both caesarean section (p<0.05) and vaginal delivery (p<0.01). In conclusion, plasma hyaluronan is increased in severe pre-eclampsia and eclampsia. The cause of the increase is unknown.


Asunto(s)
Eclampsia/sangre , Ácido Hialurónico/sangre , Preeclampsia/sangre , Adulto , Aspartato Aminotransferasas/sangre , Estudios de Casos y Controles , Creatinina/sangre , Femenino , Humanos , Recuento de Plaquetas , Embarazo
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