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1.
Database (Oxford) ; 20202020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33206959

RESUMO

The current coronavirus disease of 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus (SARS-CoV)-2, has spurred a wave of research of nearly unprecedented scale. Among the different strategies that are being used to understand the disease and develop effective treatments, the study of physical molecular interactions can provide fine-grained resolution of the mechanisms behind the virus biology and the human organism response. We present a curated dataset of physical molecular interactions focused on proteins from SARS-CoV-2, SARS-CoV-1 and other members of the Coronaviridae family that has been manually extracted by International Molecular Exchange (IMEx) Consortium curators. Currently, the dataset comprises over 4400 binarized interactions extracted from 151 publications. The dataset can be accessed in the standard formats recommended by the Proteomics Standards Initiative (HUPO-PSI) at the IntAct database website (https://www.ebi.ac.uk/intact) and will be continuously updated as research on COVID-19 progresses.


Assuntos
Betacoronavirus , Coronaviridae , Infecções por Coronavirus , Interações Hospedeiro-Patógeno , Pandemias , Pneumonia Viral , Mapas de Interação de Proteínas , COVID-19 , Humanos , Especificidade de Órgãos , Proteômica , SARS-CoV-2 , Proteínas Virais
2.
bioRxiv ; 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32587962

RESUMO

The current Coronavirus Disease 2019 (COVID-19) pandemic, caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), has spurred a wave of research of nearly unprecedented scale. Among the different strategies that are being used to understand the disease and develop effective treatments, the study of physical molecular interactions enables studying fine-grained resolution of the mechanisms behind the virus biology and the human organism response. Here we present a curated dataset of physical molecular interactions, manually extracted by IMEx Consortium curators focused on proteins from SARS-CoV-2, SARS-CoV-1 and other members of the Coronaviridae family. Currently, the dataset comprises over 2,200 binarized interactions extracted from 86 publications. The dataset can be accessed in the standard formats recommended by the Proteomics Standards Initiative (HUPO-PSI) at the IntAct database website ( www.ebi.ac.uk/intact ), and will be continuously updated as research on COVID-19 progresses.

3.
Nat Commun ; 10(1): 1098, 2019 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-30833551

RESUMO

In the original HTML version of this Article, the order of authors within the author list was incorrect. The IMEx Consortium contributing authors were incorrectly listed as the last author and should have been listed as the first author. This error has been corrected in the HTML version of the Article; the PDF version was correct at the time of publication.

4.
Bioinformatics ; 35(19): 3779-3785, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30793173

RESUMO

MOTIVATION: Combining multiple layers of information underlying biological complexity into a structured framework represent a challenge in systems biology. A key task is the formalization of such information in models describing how biological entities interact to mediate the response to external and internal signals. Several databases with signalling information, focus on capturing, organizing and displaying signalling interactions by representing them as binary, causal relationships between biological entities. The curation efforts that build these individual databases demand a concerted effort to ensure interoperability among resources. RESULTS: Aware of the enormous benefits of standardization efforts in the molecular interaction research field, representatives of the signalling network community agreed to extend the PSI-MI controlled vocabulary to include additional terms representing aspects of causal interactions. Here, we present a common standard for the representation and dissemination of signalling information: the PSI Causal Interaction tabular format (CausalTAB) which is an extension of the existing PSI-MI tab-delimited format, now designated PSI-MITAB 2.8. We define the new term 'causal interaction', and related child terms, which are children of the PSI-MI 'molecular interaction' term. The new vocabulary terms in this extended PSI-MI format will enable systems biologists to model large-scale signalling networks more precisely and with higher coverage than before. AVAILABILITY AND IMPLEMENTATION: PSI-MITAB 2.8 format and the new reference implementation of PSICQUIC are available online (https://psicquic.github.io/ and https://psicquic.github.io/MITAB28Format.html). SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Proteômica , Biologia de Sistemas , Criança , Bases de Dados Factuais , Humanos , Transdução de Sinais , Software
5.
Nat Commun ; 10(1): 10, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30602777

RESUMO

The current wealth of genomic variation data identified at nucleotide level presents the challenge of understanding by which mechanisms amino acid variation affects cellular processes. These effects may manifest as distinct phenotypic differences between individuals or result in the development of disease. Physical interactions between molecules are the linking steps underlying most, if not all, cellular processes. Understanding the effects that sequence variation has on a molecule's interactions is a key step towards connecting mechanistic characterization of nonsynonymous variation to phenotype. We present an open access resource created over 14 years by IMEx database curators, featuring 28,000 annotations describing the effect of small sequence changes on physical protein interactions. We describe how this resource was built, the formats in which the data is provided and offer a descriptive analysis of the data set. The data set is publicly available through the IntAct website and is enhanced with every monthly release.


Assuntos
Substituição de Aminoácidos , Variação Genética , Anotação de Sequência Molecular , Mutação Puntual , Mapas de Interação de Proteínas , Animais , Doença/genética , Humanos
6.
BMC Bioinformatics ; 19(1): 134, 2018 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-29642841

RESUMO

BACKGROUND: Systems biologists study interaction data to understand the behaviour of whole cell systems, and their environment, at a molecular level. In order to effectively achieve this goal, it is critical that researchers have high quality interaction datasets available to them, in a standard data format, and also a suite of tools with which to analyse such data and form experimentally testable hypotheses from them. The PSI-MI XML standard interchange format was initially published in 2004, and expanded in 2007 to enable the download and interchange of molecular interaction data. PSI-XML2.5 was designed to describe experimental data and to date has fulfilled this basic requirement. However, new use cases have arisen that the format cannot properly accommodate. These include data abstracted from more than one publication such as allosteric/cooperative interactions and protein complexes, dynamic interactions and the need to link kinetic and affinity data to specific mutational changes. RESULTS: The Molecular Interaction workgroup of the HUPO-PSI has extended the existing, well-used XML interchange format for molecular interaction data to meet new use cases and enable the capture of new data types, following extensive community consultation. PSI-MI XML3.0 expands the capabilities of the format beyond simple experimental data, with a concomitant update of the tool suite which serves this format. The format has been implemented by key data producers such as the International Molecular Exchange (IMEx) Consortium of protein interaction databases and the Complex Portal. CONCLUSIONS: PSI-MI XML3.0 has been developed by the data producers, data users, tool developers and database providers who constitute the PSI-MI workgroup. This group now actively supports PSI-MI XML2.5 as the main interchange format for experimental data, PSI-MI XML3.0 which additionally handles more complex data types, and the simpler, tab-delimited MITAB2.5, 2.6 and 2.7 for rapid parsing and download.


Assuntos
Mapas de Interação de Proteínas , Proteoma/metabolismo , Proteômica , Bases de Dados de Proteínas , Humanos , Mutação/genética , Biologia de Sistemas
7.
BMC Bioinformatics ; 19(1): 133, 2018 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-29642846

RESUMO

BACKGROUND: A number of different molecular interactions data download formats now exist, designed to allow access to these valuable data by diverse user groups. These formats include the PSI-XML and MITAB standard interchange formats developed by Molecular Interaction workgroup of the HUPO-PSI in addition to other, use-specific downloads produced by other resources. The onus is currently on the user to ensure that a piece of software is capable of read/writing all necessary versions of each format. This problem may increase, as data providers strive to meet ever more sophisticated user demands and data types. RESULTS: A collaboration between EMBL-EBI and the University of Cambridge has produced JAMI, a single library to unify standard molecular interaction data formats such as PSI-MI XML and PSI-MITAB. The JAMI free, open-source library enables the development of molecular interaction computational tools and pipelines without the need to produce different versions of software to read different versions of the data formats. CONCLUSION: Software and tools developed on top of the JAMI framework are able to integrate and support both PSI-MI XML and PSI-MITAB. The use of JAMI avoids the requirement to chain conversions between formats in order to reach a desired output format and prevents code and unit test duplication as the code becomes more modular. JAMI's model interfaces are abstracted from the underlying format, hiding the complexity and requirements of each data format from developers using JAMI as a library.


Assuntos
Linguagens de Programação , Software , Estatística como Assunto , Bases de Dados de Proteínas , Humanos , Mapas de Interação de Proteínas , Proteômica
8.
Artigo em Inglês | MEDLINE | ID: mdl-25652942

RESUMO

The evidence that two molecules interact in a living cell is often inferred from multiple different experiments. Experimental data is captured in multiple repositories, but there is no simple way to assess the evidence of an interaction occurring in a cellular environment. Merging and scoring of data are commonly required operations after querying for the details of specific molecular interactions, to remove redundancy and assess the strength of accompanying experimental evidence. We have developed both a merging algorithm and a scoring system for molecular interactions based on the proteomics standard initiative-molecular interaction standards. In this manuscript, we introduce these two algorithms and provide community access to the tool suite, describe examples of how these tools are useful to selectively present molecular interaction data and demonstrate a case where the algorithms were successfully used to identify a systematic error in an existing dataset.


Assuntos
Algoritmos , Ontologias Biológicas , Bases de Dados de Proteínas , Modelos Biológicos , Proteômica
9.
Appl Opt ; 53(28): 6351-61, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25322218

RESUMO

In this paper a low-cost, practical pixel-based flame spectrum and temperature estimation system based on flame color images is proposed. A spectral resolution of ∼ 0.4 nm is achieved with an optical system formed by a color camera, a linear model, a flame's spectral training data, and a spectral reconstruction procedure. As a proof of concept, the estimated spectra are compared to local measurements performed with a commercial spectrometer. In order to estimate the absolute flame-temperature maps, two radiometric images at different wavelengths are reconstructed and the two-color pyrometry method is applied. Experiments show errors of about 2.0% over the estimated temperature, making this system a practical tool for flame sensing in combustion-process monitoring.

10.
Heredity (Edinb) ; 113(4): 306-15, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24736785

RESUMO

Group II introns are self-splicing catalytic RNAs that act as mobile retroelements. In bacteria, they are thought to be tolerated to some extent because they self-splice and home preferentially to sites outside of functional genes, generally within intergenic regions or in other mobile genetic elements, by mechanisms including the divergence of DNA target specificity to prevent target site saturation. RmInt1 is a mobile group II intron that is widespread in natural populations of Sinorhizobium meliloti and was first described in the GR4 strain. Like other bacterial group II introns, RmInt1 tends to evolve toward an inactive form by fragmentation, with loss of the 3' terminus. We identified genomic evidence of a fragmented intron closely related to RmInt1 buried in the genome of the extant S. meliloti/S. medicae species. By studying this intron, we obtained evidence for the occurrence of intron insertion before the divergence of ancient rhizobial species. This fragmented group II intron has thus existed for a long time and has provided sequence variation, on which selection can act, contributing to diverse genetic rearrangements, and to generate pan-genome divergence after strain differentiation. The data presented here suggest that fragmented group II introns within intergenic regions closed to functionally important neighboring genes may have been microevolutionary forces driving adaptive evolution of these rhizobial species.


Assuntos
Evolução Molecular , Genoma Bacteriano , Íntrons , Sinorhizobium meliloti/genética , Sinorhizobium/genética , Sequência de Bases , Dados de Sequência Molecular , Fixação de Nitrogênio , Filogenia , Sinorhizobium/classificação , Sinorhizobium/metabolismo , Sinorhizobium meliloti/classificação , Sinorhizobium meliloti/metabolismo , Simbiose
11.
Acta Biol Hung ; 65(1): 96-106, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24561898

RESUMO

The aim of the study was to estimate the breakdown of the allochthonous litter in an artificial stream running in an agricultural area and compare it with the same values following a toxic mud spill into the same stream. Litter bags were filled with three types of leaves (Quercus robur, Populus tremula and Salix alba) and placed to the bottom of the river. Ergosterol was used to detect fungal biomass. We supposed the absence of fungi and the retardation of leaf litter decomposition. Only pH and conductivity increased significantly. Leaf mass loss after the catastrophe was much slower than in 2009 and the decay curves did not follow the exponential decay model. Prior to the catastrophe, leaf mass loss was fast in Torna, compared to other streams in the area. The reason is that the stream is modified, the bed is trapezoid and covered with concrete stones. Fungal biomass was lower, than in the pre-disaster experiment, because fungi did not have enough leaves to sporulate. Leaf mass loss followed the exponential decay curve before the disaster, but after that it was possible only after a non-change period.


Assuntos
Vazamento de Resíduos Químicos , Folhas de Planta/química , Rios/química , Desastres , Ergosterol/análise , Hungria
12.
Rev. otorrinolaringol. cir. cabeza cuello ; 74(2): 101-108, 2014. ilus, graf, tab
Artigo em Espanhol | LILACS | ID: lil-726159

RESUMO

Introducción: El examen funcional del VIII par, mediante la prueba calórica permite conocer la función del canal semicircular horizontal, dejando de lado la evaluación de otras estructuras como el complejo utrículo-sacular. Objetivo: Evaluar el rendimiento diagnóstico de pruebas vestibulares de bajo costo y complejidad cefálico para suplir esta falencia. Material y método: En 34 pacientes con indicación de estudio funcional de VIII par se realizaron, además de las pruebas tradicionales, el test visual subjetivo vertical mediante prueba del balde, la prueba de impulso cefálico a ojo desnudo, y la aplicación del cuestionario de sintomatología "Dizziness Handicap Inventory". Resultados: Considerando el VIII par clásico como patrón de oro, se encuentra evidencia objetiva de patología en 50% de la muestra. Con la incorporación de los nuevos exámenes esta cifra aumenta a 85%. Se realizó análisis de discrepancia sobre pacientes con resultados normales en el estudio tradicional, pero anormal según los nuevos exámenes. El 100% de dicho grupo presenta una puntuación patológica en el cuestionario de síntomas. Más aún, los valores de desviación de verticalidad correlacionaron fuertemente con la puntuación de sintomatología (r =0,79; p =0,002). Conclusiones: El análisis de discrepancia sugiere que los nuevos exámenes son confiables en identificar patología en el estudio. Incluir en el estudio tradicional del VIII par pruebas de baja complejidad y corta duración (menos de 5 minutos en su conjunto) podría aumentar el rendimiento diagnóstico del estudio del equilibrio en hasta 35%.


Introduction: Traditionally, the assessment of vestibular function is based on the caloric test. This procedure assesses mainly the horizontal semicircular canal function, leaving other vestibular structures aside, such as the utricule-saccule complex. Aim: To assess the diagnostic performance low complexity tests to compensate for these issues. Material and methods: 34 patients with indication for vestibular assessment were recruited. In addition to traditional testing (caloric test and postural provocation maneuvers), the mentioned Subjective Visual Vertical and Head Impulse tests were applied alongside the Dizziness Handicap Inventory for vestibular symptoms. Results: Considering caloric testing and Dix-Hallpike maneuvers as gold standard, 50% of the sample presented an objective cause of their symptomatology. When including the new test, this value increases to 85%. A discrepancy analysis was conducted on the group with normal traditional tests and abnormal new tests. 100% of this group showed symptoms score above pathological levels. Furthermore, there was a strong relationship between deviation on the Visual Vertical test and symptomatology (r =0,79; p =0,002). Conclusion: The discrepancy analysis suggests that the new tests are reliable in determining pathology on this study. It these test are included to traditional testing, diagnostic performance may increase up to 35%.


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Testes de Função Vestibular , Doenças Vestibulares/diagnóstico , Testes Calóricos , Método Simples-Cego , Doenças Vestibulares/fisiopatologia , Estudos Prospectivos , Sensibilidade e Especificidade , Teste do Impulso da Cabeça
13.
Clin Exp Immunol ; 159(2): 217-23, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19912255

RESUMO

Anti-transglutaminase antibodies are the diagnostic markers of coeliac disease. A role is suggested for infectious agents in the production of anti-transglutaminase antibodies. The aim was to measure positive anti-transglutaminase antibody levels in children with infectious diseases and to compare immunological and biological characteristics of the anti-transglutaminase antibodies derived from these children with that from coeliac patients. Two hundred and twenty-two children suffering from infectious diseases were enrolled prospectively along with seven biopsy-proven coeliacs. Serum samples were tested for anti-transglutaminase antibodies and anti-endomysium antibodies; positive samples were tested for coeliac-related human leucocyte antigen (HLA)-DQ2/8 and anti-viral antibodies. Purified anti-transglutaminase antibodies from the two study groups were tested for urea-dependent avidity, and their ability to induce cytoskeletal rearrangement and to modulate cell-cycle in Caco-2 cells, using phalloidin staining and bromodeoxyuridine incorporation assays, respectively. Nine of 222 children (4%) tested positive to anti-transglutaminase, one of whom also tested positive for anti-endomysium antibodies. This patient was positive for HLA-DQ2 and was diagnosed as coeliac following intestinal biopsy. Of the eight remaining children, two were positive for HLA-DQ8. Levels of anti-transglutaminase returned to normal in all subjects, despite a gluten-containing diet. Purified anti-transglutaminase of the two study groups induced actin rearrangements and cell-cycle progression. During an infectious disease, anti-transglutaminase antibodies can be produced temporarily and independently of gluten. The infection-triggered anti-transglutaminase antibodies have the same biological properties as that of the coeliacs, with the same in-vivo potential for damage.


Assuntos
Autoanticorpos/imunologia , Doença Celíaca/imunologia , Doenças Transmissíveis/imunologia , Transglutaminases/imunologia , Actinas/metabolismo , Adolescente , Anticorpos/farmacologia , Autoanticorpos/sangue , Células CACO-2 , Doença Celíaca/sangue , Doença Celíaca/diagnóstico , Ciclo Celular/efeitos dos fármacos , Criança , Pré-Escolar , Doenças Transmissíveis/sangue , Doenças Transmissíveis/diagnóstico , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Microscopia de Fluorescência , Estudos Prospectivos
14.
Mol Plant Microbe Interact ; 20(2): 138-45, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17313165

RESUMO

Nodulation of Medicago sativa (alfalfa) is known to be restricted to Sinorhizobium meliloti and a few other rhizobia that include the poorly characterized isolates related to Rhizobium sp. strain Or191. Distinctive features of the symbiosis between alfalfa and S. meliloti are the marked specificity from the plant to the bacteria and the strict requirement for the presence of sulfated lipochitooligosaccharides (Nod factors [NFs]) at its reducing end. Here, we present evidence of the presence of a functional nodH-encoded NF sulfotransferase in the Or191-like rhizobia. The nodH gene, present in single copy, maps to a high molecular weight megaplasmid. As in S. meliloti, a nodF homolog was identified immediately upstream of nodH that was transcribed in the opposite direction (local synteny). This novel nodH ortholog was cloned and shown to restore both NF sulfation and the Nif+Fix+ phenotypes when introduced into an S. meliloti nodH mutant. Unexpectedly, however, nodH disruption in the Or191-like bacteria did not abolish their ability to nodulate alfalfa, resulting instead in a severely delayed nodulation. In agreement with evidence from other authors, the nodH sequence analysis strongly supports the idea that the Or191-like rhizobia most likely represent a genetic mosaic resulting from the horizontal transfer of symbiotic genes from a sinorhizobial megaplasmid to a not yet clearly identified ancestor.


Assuntos
Proteínas de Bactérias/genética , Medicago sativa/microbiologia , Rhizobium/genética , Sulfotransferases/genética , Proteínas de Bactérias/metabolismo , Cromatografia em Camada Fina , Clonagem Molecular , Teste de Complementação Genética , Modelos Genéticos , Dados de Sequência Molecular , Mutação , Filogenia , Raízes de Plantas/microbiologia , Reação em Cadeia da Polimerase , Rhizobium/crescimento & desenvolvimento , Análise de Sequência de DNA , Sulfotransferases/metabolismo
15.
Microb Ecol ; 53(2): 317-27, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17186143

RESUMO

The rainforest of French Guiana is still largely unaffected by human activity. Various pristine sites like the Paracou Research Station are devoted to study this tropical ecosystem. We used culture-independent techniques, like polymerase chain reaction-temperature gradient gel electrophoresis, and construction of clone libraries of partial 16S rRNA and nifH genes, to analyze the composition of the bacterial community in the rhizosphere of mature trees of Eperua falcata and Dicorynia guianensis, both species within the Caesalpiniaceae family. E. falcata is one of the more abundant pioneer tree species in this ecosystem and so far, no root nodules have ever been found. However, its nitrogen-fixing status is regarded as "uncertain", whereas D. guianensis is clearly considered a non-nitrogen-fixing plant. The rhizospheres of these mature trees contain specific bacterial communities, including several currently found uncultured microorganisms. In these communities, there are putative nitrogen-fixing bacteria specifically associated to each tree: D. guianensis harbors several Rhizobium spp. and E. falcata members of the genera Burkholderia and Bradyrhizobium. In addition, nifH sequences in the rhizosphere of the latter tree were very diverse. Retrieved sequences were related to bacteria belonging to the alpha-, beta-, and gamma-Proteobacteria in the E. falcata rhizoplane, whereas only two sequences related to gamma-Proteobacteria were found in D. guianensis. Differences in the bacterial communities and the abundance and diversity of nifH sequences in E. falcata rhizosphere suggest that this tree could obtain nitrogen through a nonnodulating bacterial interaction.


Assuntos
Bactérias/isolamento & purificação , Nitrogênio/metabolismo , Árvores/metabolismo , Árvores/microbiologia , Bactérias/classificação , Bactérias/genética , Proteínas de Bactérias/genética , Ecossistema , Guiana Francesa , Oxirredutases/genética , Filogenia , Raízes de Plantas/microbiologia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Especificidade da Espécie , Clima Tropical
16.
Nefrologia ; 26(5): 594-9, 2006.
Artigo em Espanhol | MEDLINE | ID: mdl-17117903

RESUMO

INTRODUCTION: As is universally accepted the best form of permanent vascular access for haemodialysis is the native arteriovenous fistula. A second and third options are the politetrafluoroethylene (PTFE) AV grafts and the cuffed, tunneled, internal catheters. The overall performance and complications of catheters is clearly inferior to AV fistula. There are not many studies that compare permanent catheters to grafts in terms of functionality, survival and complications. METHODS: We analyzed 81 vascular accesses carried out from october 99 to december 03 in 59 patients and during a follow-up period of 35 months. Two groups were considered. Group 1, catheters (n 42) and group 2, grafts (n 39). Clinical aspects, comorbidity index (Wright and Kanh), dialysis dose and complications and survival of the access were registered. RESULTS: Both groups were similar in age, sex, time on haemodialysis, number of previous accesses and hospitalization days. Cardiovascular morbidity and comorbidity index were significantly higher in patients with catheter. While blood flow during dialysis was higher in grafts both groups showed no significant differences in parameters of efficacy of dialysis (Kt/V, TAC BUN and PCRn). Serum albumin was lower in patients with catheter. The number of accesses that failed was higher in the graft group being thrombosis the main complication followed by infection. Kaplan-Meier curves showed better accumulated survival of permanent catheters versus grafts (61,4% vs 9,8% at 35 months). The most frequent complication of catheter was infection while in the case of grafts it was thrombosis followed by infection. CONCLUSIONS: Although they were placed in patients with higher comorbidity, cuffed, tunneled catheters showed less number of complications and better survival than PTFE grafts in our patients in haemodialysis. The main cause of failure of both vascular access was thrombosis followed by infection. The dose of dialysis obtained was no different in both groups. Cuffed, tunneled permanent catheters are a very interesting option in a number of patients in haemodialysis and they can be an option to consider in those patients with vascular difficulties and higher comorbidities.


Assuntos
Derivação Arteriovenosa Cirúrgica , Cateteres de Demora , Diálise Renal , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Politetrafluoretileno , Fluxo Sanguíneo Regional , Estudos Retrospectivos
17.
Nefrología (Madr.) ; 26(5): 594-599, sept.-oct. 2006. ilus, tab
Artigo em Es | IBECS | ID: ibc-053451

RESUMO

La fístula arteriovenosa (FAV) autóloga es el acceso vascular permanente de elección en los pacientes en hemodiálisis. Cuando esta opción no es posible, se debería optar por una prótesis vascular de politetrafluoroetileno (PTFE) y en tercer lugar por un catéter permanente tunelizado (CPT). Objetivo: Comparar la incidencia de complicaciones, morbilidad, índices de eficacia dialítica, así como la supervivencia de los CPT vs PTFE a nivel de antebrazo. Material y métodos: Estudiamos retrospectivamente 81 accesos vasculares realizados en 59 pacientes, seguidos desde octubre-99 hasta diciembre-03. Dividimos la muestra en dos grupos en función del acceso vascular: G-I (n = 42) CPT; G-II (n = 39) PTFE. Se compararon características clínicas, índice de comorbilidad (Wright y Kanh), eficacia de diálisis, complicaciones y supervivencia. Resultados: No encontramos diferencias significativas en cuanto a los datos antropométricos, tiempo en hemodiálisis, número de accesos previos o el número de ingresos en relación al acceso vascular. Los pacientes portadores de PTFE presentaban un índice de comorbilidad inferior a los portadores de CPT o de ambos accesos. El flujo obtenido con las prótesis de PTFE era superior al obtenido con los CPT (p = 0,003). La albúmina era más elevada en el grupo de las prótesis de PTFE (p = 0,002). El número de complicaciones fue superior en el grupo de los injertos (p < 0,05), siendo la trombosis la más frecuente. Durante el seguimiento hubo que retirar más prótesis que CPT (p < 0,000), siendo el motivo más frecuente de pérdida del acceso vascular la trombosis, seguido de la infección. La supervivencia acumulada del acceso vascular a 35 meses de seguimiento, analizada mediante curvas de Kaplan-Meier, mostró una mayor supervivencia acumulada de CPT (61,4%) frente a prótesis de PTFE (9,8%) (p < 0,01). Conclusiones: Los CPT mostraron menor incidencia de complicaciones y mayor supervivencia que las prótesis de PTFE, a pesar de haber sido colocados en más de la mitad de los casos, en pacientes con una mayor comorbilidad. El principal motivo de fracaso del acceso vascular fue la trombosis seguido de la infección; se retiraron más prótesis que CPT. Finalmente, los parámetros de eficacia de diálisis fueron similares en ambos grupos


Introduction: As is universally accepted the best form of permanent vascular access for haemodialysis is the native arteriovenous fistula. A second and third options are the poliformatetrafluoroethylene (PTFE) AV grafts and the cuffed, tunneled, internal catheters. The overall performance and complications of catheters is clearly inferior to AV fistula. There are not many studies that compare permanent catheters to grafts in terms of functionality, survival and complications. Methods: We analyzed 81 vascular accesses carried out from october 99 to december 03 in 59 patients and during a follow-up period of 35 months. Two groups were considered. Group 1, catheters (n 42) and group 2, grafts (n 39). Clinical aspects, comorbidity index (Wright and Kanh), dialysis dose and complications and survival of the access were registered. Results: Both groups were similar in age, sex, time on haemodialysis, number of previous accesses and hospitalization days. Cardiovascular morbidity and comorbidity index were significantly higher in patients with catheter. While blood flow during dialysis was higher in grafts both groups showed no significant differences in parameters of efficacy of dialysis (Kt/V, TAC BUN and PCRn). Serum albumin was lower in patients with catheter. The number of accesses that failed was higher in the graft group being thrombosis the main complication followed by infection. Kaplan-Meier curves showed better accumulated survival of permanent catheters versus grafts (61,4% vs 9,8% at 35 months). The most frequent complication of catheter was infection while in the case of grafts it was thrombosis followed by infection. Conclusions: Although they were placed in patients with higher comorbidity, cuffed, tunneled catheters showed less number of complications and better survival than PTFE grafts in our patients in haemodialysis. The main cause of failure of both vascular access was thrombosis followed by infection. The dose of dialysis obtained was no different in both groups. Cuffed, tunneled permanent catheters are a very interesting option in a number of patients in haemodialysis and they can be an option to consider in those patients with vascular difficulties and higher comorbidities


Assuntos
Adulto , Humanos , Derivação Arteriovenosa Cirúrgica , Cateteres de Demora , Diálise Renal , Politetrafluoretileno , Fluxo Sanguíneo Regional , Estudos Retrospectivos
18.
Nefrologia ; 25(4): 416-21, 2005.
Artigo em Espanhol | MEDLINE | ID: mdl-16231509

RESUMO

UNLABELLED: Parathyroidectomy, in any of its forms, is considered an effective short-term treatment of renal hyperparathyroidism in patients who are not being controlled with drugs. Nevertheless, the outcome in the medium and long term of the various surgical procedures is still unclear and seems a controversial issue. We conducted a prospective study of 15 patients undergoing subtotal parathyroidectomy who were followed up for a period of 48 months after surgery. All patients were included in hemodialysis programmes. Elevated levels of parathyroid hormone which did not decrease with drug therapy recommended parathyroidectomy. The aim of our study is to determine whether subtotal parathyroidectomy is an effective technique in the medium and long term. As regards the results obtained, the levels of parathyroid hormone and calcemia remarkably decreased during the follow-up period, if compared to pre-surgery levels. The level of alkaline phosphatase also showed a reduction and the "hungry bone effect" was observed. The phosphorus and Ca-P product levels only showed a significant reduction immediately after surgery but showed an increment from the first year after surgery onwards. Hemoglobin levels did not show any alteration after parathyroidectomy. In two patients we observed a relapse of hyperparathyroidism. The anatomopathological examination revealed nodular hyperplasia in most of the cases, including the two relapses. CONCLUSION: Subtotal parathyroidectomy is an effective surgical procedure in the medium-term treatment of renal hyperparathyroidism.


Assuntos
Hiperparatireoidismo Secundário/cirurgia , Paratireoidectomia , Adulto , Feminino , Seguimentos , Humanos , Hiperparatireoidismo Secundário/sangue , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Estudos Prospectivos , Recidiva , Diálise Renal , Fatores de Tempo
19.
Nefrología (Madr.) ; 25(4): 416-421, jul.-ago. 2005. tab
Artigo em Es | IBECS | ID: ibc-042330

RESUMO

La paratiroidectomía en cualquiera de sus modalidades se considera un tratamiento eficaz a corto plazo en el hiperparatiroidismo renal no controlado medicamente. Sin embargo, no queda claro y parece controvertido el resultado a medio- largo plazo de las diferentes técnicas quirúrgicas. Realizamos un estudio prospectivo de 15 pacientes sometidos a paratiroidectomía subtotal. El seguimiento postoperatorio fue de 48 meses. Todos los pacientes estaban en programa de hemodiálisis. La indicación de paratiroidectomía fue una hormona paratiroidea elevada a pesar de tratamiento médico. El objetivo del estudio fue determinar si la paratiroidectomía subtotal es un procedimiento eficaz a medio-largo plazo. En cuanto a los resultados obtenidos, podemos decir que la paratohormona descendió con respecto a los niveles precirugía de forma significativa durante los años de seguimiento, al igual que ocurrió con la calcemia. La Fosfatasa Alcalina también se vio afectada considerándose el «efecto del hueso hambriento». Tanto el fósforo como el producto Ca-P sólo sufren un descenso significativo en el control postcirugía elevándose a partir del primer año de la intervención. La hemoglobina no se ve afectada por la paratiroidectomía. En dos casos hubo recurrencia del hiperparatiroidismo. El resultado anatomopatológico de la mayoría de los casos fue Hiperplasia Nodular, incluidos los casos de recurrencia. Conclusión: La paratiroidectomía subtotal es una técnica quirúrgica efectiva en el tratamiento a medio plazo del hiperparatiroidismo renal


Parathyroidectomy, in any of its forms, is considered an effective short-term treatment of renal hyperparathyroidism in patients who are not being controlled with drugs. Nevertheless, the outcome in the medium and long term of the various surgical procedures is still unclear and seems a controversial issue. We conducted a prospective study of 15 patients undergoing subtotal parathyroidectomy who were followed up for a period of 48 months after surgery. All patients were included in hemodialysis programmes. Elevated levels of parathyroid hormone which did not decrease with drug therapy recommended parathyroidectomy. The aim of our study is to determine whether subtotal parathyroidectomy is an effective technique in the medium and long term. As regards the results obtained, the levels of parathyroid hormone and calcemia remarkably decreased during the follow-up period, if compared to pre-surgery levels. The level of alkaline phosphatase also showed a reduction and the «hungry bone effect» was observed. The phosphorus and Ca-P product levels only showed a significant reduction immediately after surgery but showed an increment from the first year after surgery onwards. Hemoglobin levels did not show any alteration after parathyroidectomy. In two patients we observed a relapse of hyperparathyroidism. The anatomopathological examination revealed nodular hyperplasia in most of the cases, including the two relapses


Assuntos
Adulto , Pessoa de Meia-Idade , Humanos , Hiperparatireoidismo Secundário/cirurgia , Paratireoidectomia , Seguimentos , Hiperparatireoidismo Secundário/sangue , Insuficiência Renal Crônica/terapia , Hormônio Paratireóideo/sangue , Estudos Prospectivos , Diálise Renal , Fatores de Tempo
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