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1.
Front Mol Biosci ; 9: 842149, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35281256

RESUMEN

The family of the human small Heat Shock Proteins (HSPBs) consists of ten members of chaperones (HSPB1-HSPB10), characterized by a low molecular weight and capable of dimerization and oligomerization forming large homo- or hetero-complexes. All HSPBs possess a highly conserved centrally located α-crystallin domain and poorly conserved N- and C-terminal domains. The main feature of HSPBs is to exert cytoprotective functions by preserving proteostasis, assuring the structural maintenance of the cytoskeleton and acting in response to cellular stresses and apoptosis. HSPBs take part in cell homeostasis by acting as holdases, which is the ability to interact with a substrate preventing its aggregation. In addition, HSPBs cooperate in substrates refolding driven by other chaperones or, alternatively, promote substrate routing to degradation. Notably, while some HSPBs are ubiquitously expressed, others show peculiar tissue-specific expression. Cardiac muscle, skeletal muscle and neurons show high expression levels for a wide variety of HSPBs. Indeed, most of the mutations identified in HSPBs are associated to cardiomyopathies, myopathies, and motor neuropathies. Instead, mutations in HSPB4 and HSPB5, which are also expressed in lens, have been associated with cataract. Mutations of HSPBs family members encompass base substitutions, insertions, and deletions, resulting in single amino acid substitutions or in the generation of truncated or elongated proteins. This review will provide an updated overview of disease-related mutations in HSPBs focusing on the structural and biochemical effects of mutations and their functional consequences.

2.
Anim Genet ; 50(6): 718-725, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31512748

RESUMEN

Targeted GBS is a recent approach for obtaining an effective characterization for hundreds to thousands of markers. The high throughput of next-generation sequencing technologies, moreover, allows sample multiplexing. The aims of this study were to (i) define a panel of single nucleotide polymorphisms (SNPs) in the cat, (ii) use GBS for profiling 16 cats, and (iii) evaluate the performance with respect to the inference using standard approaches at different coverage thresholds, thereby providing useful information for designing similar experiments. Probes for sequencing 230 variants were designed based on the Felis_catus_8.0. 8.0 genome. The regions comprised anonymous and non-anonymous SNPs. Sixteen cat samples were analysed, some of which had already been genotyped in a large group of loci and one having been whole-genome sequenced in the 99_Lives Cat Genome Sequencing Project. The accuracy of the method was assessed by comparing the GBS results with the genotypes already available. Overall, GBS achieved good performance, with 92-96% correct assignments, depending on the coverage threshold used to define the set of trustable genotypes. Analyses confirmed that (i) the reliability of the inference of each genotype depends on the coverage at that locus and (ii) the fraction of target loci whose genotype can be inferred correctly is a function of the total coverage. GBS proves to be a valid alternative to other methods. Data suggested a depth of less than 11× is required for greater than 95% accuracy. However, sequencing depth must be adapted to the total size of the targets to ensure proper genotype inference.


Asunto(s)
Gatos/genética , Animales , Genoma , Técnicas de Genotipaje , Repeticiones de Microsatélite , Polimorfismo de Nucleótido Simple
3.
Vet J ; 232: 65-69, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29428095

RESUMEN

Flow cytometry (FC) is increasingly being used for immunophenotyping and staging of canine lymphoma. The aim of this retrospective study was to assess pre-analytical variables that might influence the diagnostic utility of FC of lymph node (LN) fine needle aspirate (FNA) specimens from dogs with lymphoproliferative diseases. The study included 987 cases with LN FNA specimens sent for immunophenotyping that were submitted to a diagnostic laboratory in Italy from 2009 to 2015. Cases were grouped into 'diagnostic' and 'non-diagnostic'. Pre-analytical factors analysed by univariate and multivariate analyses were animal-related factors (breed, age, sex, size), operator-related factors (year, season, shipping method, submitting veterinarian) and sample-related factors (type of sample material, cellular concentration, cytological smears, artefacts). The submitting veterinarian, sample material, sample cellularity and artefacts affected the likelihood of having a diagnostic sample. The availability of specimens from different sites and of cytological smears increased the odds of obtaining a diagnostic result. Major artefacts affecting diagnostic utility included poor cellularity and the presence of dead cells. Flow cytometry on LN FNA samples yielded conclusive results in more than 90% of cases with adequate sample quality and sampling conditions.


Asunto(s)
Enfermedades de los Perros/diagnóstico , Citometría de Flujo/veterinaria , Trastornos Linfoproliferativos/veterinaria , Animales , Biopsia con Aguja Fina/veterinaria , Perros , Femenino , Citometría de Flujo/métodos , Italia , Leucemia/diagnóstico , Leucemia/patología , Leucemia/veterinaria , Ganglios Linfáticos/patología , Linfoma/diagnóstico , Linfoma/patología , Linfoma/veterinaria , Trastornos Linfoproliferativos/diagnóstico , Trastornos Linfoproliferativos/patología , Masculino , Estudios Retrospectivos , Especificidad de la Especie
4.
Poult Sci ; 97(3): 791-802, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29272469

RESUMEN

Genetic variation enables both adaptive evolutionary changes and artificial selection. Genetic makeup of populations is the result of a long-term process of selection and adaptation to specific environments and ecosystems. The aim of this study was to characterize the genetic variability of México's chicken population to reveal any underlying population structure. A total of 213 chickens were sampled in different rural production units located in 25 states of México. Genotypes were obtained using the Affymetrix Axiom® 600 K Chicken Genotyping Array. The Identity by Descent (IBD) and the principal components analysis (PCA) were performed by SVS software on pruned single nucleotide polymorphisms (SNPs).ADMIXTURE analyses identified 3 ancestors and the proportion of the genetic contribution of each of them has been determined in each individual. The results of the Neighbor-Joining (NJ) analysis resulted consistent with those obtained by the PCA. All methods utilized in this study did not allow a classification of Mexican chicken in distinct clusters or groups. A total of 3,059 run of homozygosity (ROH) were identified and, being mainly short in length (<4 Mb), these regions are indicative of a low inbreeding level in the population. Finally, findings from the ROH analysis indicated the presence of natural selective pressure in the population of Mexican chicken.The study indicates that the Mexican chicken clearly appear to be a unique creole chicken population that was not subjected to a specific artificial selection. Results provide a genetic knowledge that can be used as a basis for the genetic management of a unique and very large creole population, especially in the view of using it in production of hybrids to increase the productivity and economic revenue of family farming agriculture, which is widely present in México.


Asunto(s)
Pollos/genética , Variación Genética , Selección Genética , Animales , Marcadores Genéticos , México , Polimorfismo de Nucleótido Simple , Análisis de Componente Principal
5.
Vet Comp Oncol ; 16(2): 246-252, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29205839

RESUMEN

Canine nodal marginal zone lymphoma (nMZL) is classified as an indolent lymphoma. Such lymphomas are typified by low mitotic rate and slow clinical progression. While the clinical behaviour of canine splenic MZL has been described, characterized by an indolent course and a good prognosis following splenectomy, there are no studies specifically describing nMZL. The aim of this study was to describe the clinical features of and outcome for canine nMZL. Dogs with histologically confirmed nMZL undergoing a complete staging work-up (including blood analysis, flow cytometry [FC] on lymph node [LN], peripheral blood and bone marrow, imaging, histology and immunohistochemistry on a surgically removed peripheral LN) were retrospectively enrolled. Treatment consisted of chemotherapy or chemo-immunotherapy. Endpoints were response rate (RR), time to progression (TTP) and lymphoma-specific survival (LSS). A total of 35 cases were enrolled. At diagnosis, all dogs showed generalized lymphadenopathy. One-third was systemically unwell. All dogs had stage V disease; one-third also had extranodal involvement. The LN population was mainly composed of medium-sized CD21+ cells with scant resident normal lymphocytes. Histology revealed diffuse LN involvement, referring to "late-stage" MZL. Median TTP and LSS were 149 and 259 days, respectively. Increased LDH activity and substage b were significantly associated with a shorter LSS. Dogs with nMZL may show generalized lymphadenopathy and an advanced disease stage. Overall, the outcome is poor, despite the "indolent" designation. The best treatment option still needs to be defined.


Asunto(s)
Enfermedades de los Perros/patología , Linfoma de Células B de la Zona Marginal/veterinaria , Animales , Antineoplásicos/uso terapéutico , Terapia Combinada/métodos , Terapia Combinada/veterinaria , Enfermedades de los Perros/tratamiento farmacológico , Perros , Femenino , Inmunohistoquímica/veterinaria , Inmunoterapia/veterinaria , Italia , Estimación de Kaplan-Meier , Ganglios Linfáticos/patología , Linfoma de Células B de la Zona Marginal/tratamiento farmacológico , Linfoma de Células B de la Zona Marginal/patología , Masculino , Estadificación de Neoplasias , Estudios Retrospectivos , Sobrevida , Resultado del Tratamiento
6.
BMC Genet ; 18(1): 61, 2017 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-28673234

RESUMEN

BACKGROUND: Copy number variations are genome polymorphism that influence phenotypic variation and are an important source of genetic variation in populations. The aim of this study was to investigate genetic variability in the Mexican Creole chicken population using CNVs. RESULTS: The Hidden Markov Model of the PennCNV software detected a total of 1924 CNVs in the genome of the 256 samples processed with Axiom® Genome-Wide Chicken Genotyping Array (Affymetrix). The mapped CNVs comprised 1538 gains and 386 losses, resulting at population level in 1216 CNV regions (CNVRs), of which 959 gains, 226 losses and 31 complex (i.e. containing both losses and gains). The CNVRs covered a total of 47 Mb of the whole genome sequence length, corresponding to 5.12% of the chicken galGal4 autosome assembly. CONCLUSIONS: This study allowed a deep insight into the structural variation in the genome of unselected Mexican chicken population, which up to now has not been genetically characterized. The genomic study disclosed that the population, even if presenting extreme morphological variation, cannot be organized in differentiated genetic subpopulations. Finally this study provides a chicken CNV map based on the 600 K SNP chip array jointly with a genome-wide gene copy number estimates in a native unselected for more than 500 years chicken population.


Asunto(s)
Pollos/genética , Variaciones en el Número de Copia de ADN , Polimorfismo de Nucleótido Simple , Animales , Marcadores Genéticos , Genoma , México
7.
Vet Immunol Immunopathol ; 187: 14-19, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28494924

RESUMEN

Canine T-zone lymphoma (TZL) is a peculiar lymphoma subtype characterized by an indolent clinical course and aberrant CD45-negative phenotype, commonly recognized by flow cytometry (FC). Recent studies have described clinical presentation and behavior, but to date the mechanisms behind the loss of CD45 protein expression have never been investigated. The aims of this study were: 1) to confirm the absence of CD45 in canine TZL via the concomitant use of FC and immunohistochemistry with two different sources of antibody; and 2) to investigate the amount of CD45 transcript and the presence of CD45 gene in the neoplastic cells of dogs affected by TZL. 57 lymph node aspirates were included in the present study: 40 (70.2%) TZLs, 7 (12.3%) high grade T-cell lymphomas and 10 (17.5%) reactive lymph nodes. Neoplastic cells and normal T-cells were isolated from TZL and reactive lymph nodes, respectively, via cell sorting. Immunohistochemistry was performed on 2 TZL, 2 reactive lymph nodes and 2 Peripheral T-cell Lymphomas. Total RNA and genomic DNA were extracted from lymph-nodes aspirates. Two different quantitative real-time PCR experiments were designed, to determine the amount of the CD45 transcript and of the corresponding gene fragment. All TZL cases were negative for CD45 at immunohistochemistry. CD45 transcript amount was significantly lower in TZL compared to controls (p<0.001). This difference was not significant (p=0.584) for CD45 DNA load, that was similar between TZL and controls. Moreover, CD45 transcript amount was inversely correlated with the percentage of neoplastic cells in each TZL sample (p=0.010). These results confirm that CD45 protein is lacking on cell surface irrespective of the technique and antibody source adopted. This phenotypic aberrancy is apparently due to the absence of gene transcription, as CD45 DNA was present, whereas CD45 transcript was virtually absent in the neoplastic cells. The data here reported support further studies investigating possible factors impairing CD45 gene transcription.


Asunto(s)
Enfermedades de los Perros/metabolismo , Antígenos Comunes de Leucocito/metabolismo , Linfoma de Células T/veterinaria , Animales , Enfermedades de los Perros/inmunología , Enfermedades de los Perros/patología , Perros , Citometría de Flujo/veterinaria , Regulación Neoplásica de la Expresión Génica , Linfoma de Células T/inmunología , Linfoma de Células T/metabolismo , Linfoma de Células T/patología , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria
8.
Animal ; 11(5): 737-745, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27819220

RESUMEN

Genomic and genetic variation among six Italian chicken native breeds (Livornese, Mericanel della Brianza, Milanino, Bionda Piemontese, Bianca di Saluzzo and Siciliana) were studied using single nucleotide polymorphism (SNP) and copy number variants (CNV) as markers. A total of 94 DNA samples genotyped with Axiom® Genome-Wide Chicken Genotyping Array (Affymetrix) were used in the analyses. The results showed the genetic and genomic variability occurring among the six Italian chicken breeds. The genetic relationship among animals was established with a principal component analysis. The genetic diversity within breeds was calculated using heterozygosity values (expected and observed) and with Wright's F-statistics. The individual-based CNV calling, based on log R ratio and B-allele frequency values, was done by the Hidden-Markov Model (HMM) of PennCNV software on autosomes. A hierarchical agglomerative clustering was applied in each population according to the absence or presence of definite CNV regions (CNV were grouped by overlapping of at least 1 bp). The CNV map was built on a total of 1003 CNV found in individual samples, after grouping by overlaps, resulting in 564 unique CNV regions (344 gains, 213 losses and 7 complex), for a total of 9.43 Mb of sequence and 1.03% of the chicken assembly autosome. All the approaches using SNP data showed that the Siciliana breed clearly differentiate from other populations, the Livornese breed separates into two distinct groups according to the feather colour (i.e. white and black) and the Bionda Piemontese and Bianca di Saluzzo breeds are closely related. The genetic variability found using SNP is comparable with that found by other authors in the same breeds using microsatellite markers. The CNV markers analysis clearly confirmed the SNP results.


Asunto(s)
Pollos/genética , Variación Genética , Genoma , Animales , Variaciones en el Número de Copia de ADN , Marcadores Genéticos , Secuenciación de Nucleótidos de Alto Rendimiento/veterinaria , Italia , Polimorfismo de Nucleótido Simple
9.
Vet Comp Oncol ; 14(4): 409-416, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25623886

RESUMEN

Canine acute leukaemias (ALs) have a poor prognosis, with reported survival times (ST) of only a few weeks or months. Also, clinical studies assessing prognostic factors are lacking. This study aims to retrospectively assess variables that predict ST in dogs with AL, and to identify correlations between outcome and therapeutic protocols. Diagnosis and sub-classification into AL subtypes was made based on haematological findings, morphological assessment and flow cytometric immunophenotyping. Clinical-pathological features of AL subtypes at presentation concurred with those described in the literature. A normal neutrophil count at presentation significantly prolonged ST (P = 0.027). Additionally, there was a trend for anaemic dogs to have shorter survival compared with those without anaemia, and the incorporation of cytosine in the chemotherapy protocol produced a moderate but not significant increase in median ST for dogs with AL. Further prospective studies with standardized treatments are needed to confirm and improve our results.


Asunto(s)
Enfermedades de los Perros/patología , Leucemia/veterinaria , Enfermedad Aguda , Envejecimiento , Animales , Perros , Femenino , Leucemia/patología , Masculino , Estudios Retrospectivos
10.
Vet Comp Oncol ; 14 Suppl 1: 117-26, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26040658

RESUMEN

Published studies, taken together, suggest the existence of a single canine lymphoma entity, with a small clear cell appearance by cytological evaluation, a histopathological T-zone pattern and an aberrant CD45-negative T-cell phenotype, mostly characterized by long-term survival. We describe clinical presentation and outcome in a retrospective case series of canine small clear cell/T-zone lymphoma. Despite the reported predisposition of Golden retriever, this breed was not represented in our case series. Most dogs presented with stage V disease, whereas only few had clinical signs or peripheral cytopenias. Blood was almost always more infiltrated than bone marrow. Median survival confirmed the favourable prognosis described in literature, but a few dogs died within a short time. Also, a subgroup of dogs developed second malignancies, eventually leading to death. We did not investigate possible prognostic factors because of the wide variety in treatments, and further studies are needed to identify high-risk animals.


Asunto(s)
Enfermedades de los Perros/sangre , Enfermedades de los Perros/patología , Antígenos Comunes de Leucocito/biosíntesis , Linfoma de Células T/veterinaria , Animales , Médula Ósea/patología , Perros , Femenino , Citometría de Flujo , Inmunofenotipificación , Antígenos Comunes de Leucocito/sangre , Linfoma de Células T/sangre , Linfoma de Células T/patología , Masculino , Registros Médicos , Estadificación de Neoplasias/veterinaria , Pronóstico , Estudios Retrospectivos , Sobrevida
11.
Anim Genet ; 45(4): 485-99, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24909189

RESUMEN

A selective DNA pooling approach was applied to identify QTL for conjugated linoleic acid (CLA), vaccenic acid (VA) and Δ(9) -desaturase (D9D) milk content in Italian Brown Swiss dairy cattle. Milk samples from 60 animals with higher values (after correction for environmental factors) and 60 animals with lower values for each of these traits from each of five half-sib families were pooled separately. The pools were genotyped using the Illumina BovineSNP50 BeadChip. Sire allele frequencies were compared between high and low tails at the sire and marker level for SNPs for which the sires were heterozygous. An r procedure was implemented to perform data analysis in a selective DNA pooling design. A correction for multiple tests was applied using the proportion of false positives among all test results. BTA 19 showed the largest number of markers in association with CLA. Associations between SNPs and the VA and Δ(9) -desaturase traits were found on several chromosomes. A bioinformatics survey identified genes with an important role in pathways for milk fat and fatty acids metabolism within 1 Mb of SNP markers associated with fatty acids contents.


Asunto(s)
Bovinos/genética , Ácidos Linoleicos Conjugados/genética , Ácidos Oléicos/genética , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Estearoil-CoA Desaturasa/genética , Animales , Bovinos/metabolismo , Femenino , Frecuencia de los Genes , Ácidos Linoleicos Conjugados/metabolismo , Glándulas Mamarias Animales/enzimología , Glándulas Mamarias Animales/metabolismo , Leche/química , Ácidos Oléicos/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos/veterinaria , Estearoil-CoA Desaturasa/metabolismo
12.
J Anim Breed Genet ; 127(5): 352-60, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20831559

RESUMEN

To provide useful knowledge on goat breed origin and history, we studied the mitochondrial DNA (mtDNA) of 69 goats from five different breeds, Camosciata delle Alpi, Maltese, Nubian, Saanen and Sarda, and one population, the Tunisian. All goats analysed displayed a moderate haplotype and nucleotide diversity. The highest was in the Sarda - the autochthonous breed reared in Sardinia. On the basis of mtDNA control region sequences, animals showed a high genetic haplotype diversity, 35 haplotypes were each represented by a single sequence and only a few haplotypes were shared among the animals. New haplotypes of goats reared in the Mediterranean area were identified and the majority of Italian goats belonged to haplogroup A. This result confirmed worldwide distribution and diversity of haplogroup A.


Asunto(s)
ADN Mitocondrial/química , Cabras/genética , Polimorfismo Genético , Animales , Haplotipos , Región Mediterránea , Alineación de Secuencia
13.
Anim Biotechnol ; 21(2): 140-8, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20379891

RESUMEN

This study examined breed-specific stress-related hormonal and gene expression profiles in three Italian chicken breeds (Valdarnese Bianca, Bionda Piemontese, Robusta Maculata) reared in controlled conditions. Glucocorticoids work through the glucocorticoid receptor (GR), which modulates target genes transcription. We investigated breed-specific changes in corticosterone (ELISA) and GR expression. GR mRNA levels were analyzed using one-tube, two-temperature real-time PCR for absolute quantification of the gene expression by the standard curve method. Our results show high expression of GR in hepatic tissue. Significant effect of the breed was recorded for plasma corticosterone concentration: Valdarnese Bianca 3.35 ng/mL, Bionda Piemontese 1.73 ng/mL, Robusta Maculata 2.02 ng/mL. Breed specific gene expression has been recorded with a GR ranging from 1.12E+04 (Robusta Maculata) to 1.00E+05 (Bionda Piemontese) mRNA copy number/100 ng total RNA. Negative correlation was found between gene expression and blood corticosterone level.


Asunto(s)
Pollos , Corticosterona/sangre , Hígado/metabolismo , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Animales , Pollos/genética , Pollos/metabolismo , Regulación de la Expresión Génica , Italia , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
16.
Ann Oncol ; 20(4): 655-9, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19150936

RESUMEN

BACKGROUND: The steroidal aromatase inhibitor exemestane has demonstrated efficacy for the treatment of breast cancer in the metastatic and adjuvant settings. Smaller trials have also reported efficacy in the neo-adjuvant setting. PATIENTS AND METHODS: This phase II, open-label, multicentre study examined the efficacy and safety of neo-adjuvant exemestane in women aged >70 years with operable, receptor-rich breast cancer. Consecutive eligible patients received exemestane 25 mg/day for 6 months before planned surgery. The primary end point was clinical response. RESULTS: Overall, 117 patients were recruited (median age 80 years). The objective response rate in 112 assessable patients (85 with clinical and mammographic evaluation; 27 with clinical evaluation only) was 69.6% (two complete responses; 76 partial responses). In patients who responded, median tumour size reduced from 4.81 to 2.12 cm. Seventy-seven patients (68.7%) continued to surgery. Of the 40 patients eligible for breast-conserving surgery, 34 (85%) deemed unfit for this procedure at baseline. Exemestane-related adverse events were unremarkable except for grade 3 allergic skin reactions in two patients (1.8%). CONCLUSION: Neo-adjuvant exemestane given for 6 months appears to be effective for receptor-rich breast cancer in older patients. There may now be sufficient evidence to support the use of neo-adjuvant in this patient population.


Asunto(s)
Androstadienos/uso terapéutico , Antineoplásicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Androstadienos/administración & dosificación , Androstadienos/efectos adversos , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Neoplasias de la Mama/cirugía , Quimioterapia Adyuvante , Terapia Combinada , Femenino , Humanos , Resultado del Tratamiento
17.
Int J Artif Organs ; 28(7): 678-85, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16049901

RESUMEN

A method for quantitative analysis of platelet deposition under flow is discussed here. The model system is based upon perfusion of blood platelets over an adhesive substrate immobilized on a glass coverslip acting as the lower surface of a rectangular flow chamber. The perfusion apparatus is mounted onto an inverted microscope equipped with epifluorescent illumination and intensified CCD video camera. Characterization is based on information obtained from a specific image analysis method applied to continuous sequences of microscopical images. Platelet recognition across the sequence of images is based on a time-dependent, bidimensional, gaussian-like pdf. Once a platelet is located,the variation of its position and shape as a function of time (i.e., the platelet history) can be determined. Analyzing the history we can establish if the platelet is moving on the surface, the frequency of this movement and the distance traveled before its resumes the velocity of a non-interacting cell. Therefore, we can determine how long the adhesion would last which is correlated to the resistance of the platelet-substrate bond. This algorithm enables the dynamic quantification of trajectories, as well as residence times, arrest and release frequencies for a high numbers of platelets at the same time. Statistically significant conclusions on platelet-surface interactions can then be obtained. An image analysis tool of this kind can dramatically help the investigation and characterization of the thrombogenic properties of artificial surfaces such as those used in artificial organs and biomedical devices.


Asunto(s)
Circulación Sanguínea/fisiología , Plaquetas/fisiología , Adhesividad Plaquetaria/fisiología , Algoritmos , Plaquetas/ultraestructura , Movimiento Celular/fisiología , Humanos , Procesamiento de Imagen Asistido por Computador , Microscopía Fluorescente , Microscopía por Video , Modelos Cardiovasculares , Factor de von Willebrand/fisiología
20.
J Biol Regul Homeost Agents ; 18(2): 187-92, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15471226

RESUMEN

We describe herein a novel in vitro approach that can be used effectively to obtain valuable insights into the role of platelets, various coagulation proteins as well as proteins of the subendothelial extracellular matrix involved in the hemostatic and thrombotic processes occurring under microgravity. At difference with other experimental approaches proposed in the past our device operates in a closed system and under different shear forces, which better mimics flow conditions occurring in vessels. Furthermore our device by allowing real time monitoring of the thrombotic process and its underlying mechanisms can be regarded as a reliable system for the precise assessment of platelet function.


Asunto(s)
Medicina Aeroespacial/instrumentación , Coagulación Sanguínea/fisiología , Ingravidez , Plaquetas/fisiología , Pruebas Hematológicas/instrumentación , Hemostasis/fisiología , Humanos , Microfluídica/instrumentación , Microfluídica/métodos , Microscopía Fluorescente , Trombosis/fisiopatología
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