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1.
Strahlenther Onkol ; 192(11): 815-819, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27380001

RESUMEN

OBJECTIVE: The Gamma Knife Icon (Elekta AB, Stockholm, Sweden) allows frameless stereotactic treatment using a combination of cone beam computer tomography (CBCT), a thermoplastic mask system, and an infrared-based high-definition motion management (HDMM) camera system for patient tracking during treatment. We report on the first patient with meningioma at the left petrous bone treated with adaptive fractionated stereotactic radiotherapy (a-gkFSRT). METHODS: The first patient treated with Gamma Knife Icon at our institute received MR imaging for preplanning before treatment. For each treatment fraction, a daily CBCT was performed to verify the actual scull/tumor position. The system automatically adapted the planned shot positions to the daily position and recalculated the dose distribution (online adaptive planning). During treatment, the HDMM system recorded the intrafractional patient motion. Furthermore, the required times were recorded to define a clinical treatment slot. RESULTS: Total treatment time was around 20 min. Patient positioning needed 0.8 min, CBCT positioning plus acquisition 1.65 min, CT data processing and adaptive planning 2.66 min, and treatment 15.6 min. The differences for the five daily CBCTs compared to the reference are for rotation: -0.59 ± 0.49°/0.18 ± 0.20°/0.05 ± 0.36° and for translation: 0.94 ± 0.52 mm/-0.08 ± 0.08 mm/-1.13 ± 0.89 mm. Over all fractions, an intrafractional movement of 0.13 ± 0.04 mm was observed. CONCLUSION: The Gamma Knife Icon allows combining the accuracy of the stereotactic Gamma Knife system with the flexibility of fractionated treatment with the mask system and CBCT. Furthermore, the Icon system introduces a new online patient tracking system to the clinical routine. The interfractional accuracy of patient positioning was controlled with a thermoplastic mask and CBCT.


Asunto(s)
Tomografía Computarizada de Haz Cónico/instrumentación , Neoplasias Meníngeas/radioterapia , Meningioma/radioterapia , Radiocirugia/instrumentación , Planificación de la Radioterapia Asistida por Computador/instrumentación , Radioterapia Guiada por Imagen/instrumentación , Anciano , Tomografía Computarizada de Haz Cónico/métodos , Fraccionamiento de la Dosis de Radiación , Diseño de Equipo , Análisis de Falla de Equipo , Femenino , Humanos , Neoplasias Meníngeas/diagnóstico por imagen , Meningioma/diagnóstico por imagen , Radiocirugia/métodos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia Guiada por Imagen/métodos , Integración de Sistemas , Resultado del Tratamiento
2.
Psychol Med ; 45(11): 2437-46, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25851411

RESUMEN

BACKGROUND: Distinguishing bipolar disorder (BP) from major depressive disorder (MDD) has important relevance for prognosis and treatment. Prior studies have identified clinical features that differ between these two diseases but have been limited by heterogeneity and lack of replication. We sought to identify depression-related features that distinguish BP from MDD in large samples with replication. METHOD: Using a large, opportunistically ascertained collection of subjects with BP and MDD we selected 34 depression-related clinical features to test across the diagnostic categories in an initial discovery dataset consisting of 1228 subjects (386 BPI, 158 BPII and 684 MDD). Features significantly associated with BP were tested in an independent sample of 1000 BPI cases and 1000 MDD cases for classifying ability in receiver operating characteristic (ROC) analysis. RESULTS: Seven clinical features showed significant association with BPI compared with MDD: delusions, psychomotor retardation, incapacitation, greater number of mixed symptoms, greater number of episodes, shorter episode length, and a history of experiencing a high after depression treatment. ROC analyses of a model including these seven factors showed significant evidence for discrimination between BPI and MDD in an independent dataset (area under the curve = 0.83). Only two features (number of mixed symptoms, and feeling high after an antidepressant) showed an association with BPII versus MDD. CONCLUSIONS: Our study suggests that clinical features distinguishing depression in BPI versus MDD have important classification potential for clinical practice, and should also be incorporated as 'baseline' features in the evaluation of novel diagnostic biomarkers.


Asunto(s)
Síntomas Afectivos/diagnóstico , Trastorno Bipolar/diagnóstico , Trastorno Depresivo Mayor/diagnóstico , Adulto , Diagnóstico Diferencial , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Curva ROC
3.
Mol Psychiatry ; 19(12): 1267-74, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24296977

RESUMEN

A study of genome-wide gene expression in major depressive disorder (MDD) was undertaken in a large population-based sample to determine whether altered expression levels of genes and pathways could provide insights into biological mechanisms that are relevant to this disorder. Gene expression studies have the potential to detect changes that may be because of differences in common or rare genomic sequence variation, environmental factors or their interaction. We recruited a European ancestry sample of 463 individuals with recurrent MDD and 459 controls, obtained self-report and semi-structured interview data about psychiatric and medical history and other environmental variables, sequenced RNA from whole blood and genotyped a genome-wide panel of common single-nucleotide polymorphisms. We used analytical methods to identify MDD-related genes and pathways using all of these sources of information. In analyses of association between MDD and expression levels of 13 857 single autosomal genes, accounting for multiple technical, physiological and environmental covariates, a significant excess of low P-values was observed, but there was no significant single-gene association after genome-wide correction. Pathway-based analyses of expression data detected significant association of MDD with increased expression of genes in the interferon α/ß signaling pathway. This finding could not be explained by potentially confounding diseases and medications (including antidepressants) or by computationally estimated proportions of white blood cell types. Although cause-effect relationships cannot be determined from these data, the results support the hypothesis that altered immune signaling has a role in the pathogenesis, manifestation, and/or the persistence and progression of MDD.


Asunto(s)
Trastorno Depresivo Mayor/genética , Interferón Tipo I/genética , Adulto , Trastorno Depresivo Mayor/tratamiento farmacológico , Femenino , Expresión Génica , Estudio de Asociación del Genoma Completo , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Recurrencia , Autoinforme , Análisis de Secuencia de ARN/métodos , Transducción de Señal/genética , Población Blanca/genética , Adulto Joven
4.
Psychol Med ; 42(7): 1449-59, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22099954

RESUMEN

BACKGROUND: Co-morbidity of mood and anxiety disorders is common and often associated with greater illness severity. This study investigates clinical correlates and familiality of four anxiety disorders in a large sample of bipolar disorder (BP) and major depressive disorder (MDD) pedigrees. METHOD: The sample comprised 566 BP families with 1416 affected subjects and 675 MDD families with 1726 affected subjects. Clinical characteristics and familiality of panic disorder, social phobia, specific phobia and obsessive-compulsive disorder (OCD) were examined in BP and MDD pedigrees with multivariate modeling using generalized estimating equations. RESULTS: Co-morbidity between mood and anxiety disorders was associated with several markers of clinical severity, including earlier age of onset, greater number of depressive episodes and higher prevalence of attempted suicide, when compared with mood disorder without co-morbid anxiety. Familial aggregation was found with co-morbid panic and OCD in both BP and MDD pedigrees. Specific phobia showed familial aggregation in both MDD and BP families, although the findings in BP were just short of statistical significance after adjusting for other anxiety co-morbidities. We found no evidence for familiality of social phobia. CONCLUSIONS: Our findings suggest that co-morbidity of MDD and BP with specific anxiety disorders (OCD, panic disorder and specific phobia) is at least partly due to familial factors, which may be of relevance to both phenotypic and genetic studies of co-morbidity.


Asunto(s)
Trastornos de Ansiedad/epidemiología , Trastorno Bipolar/epidemiología , Trastorno Depresivo Mayor/epidemiología , Modelos Estadísticos , Linaje , Adulto , Trastornos de Ansiedad/genética , Trastorno Bipolar/genética , Comorbilidad , Trastorno Depresivo Mayor/genética , Femenino , Predisposición Genética a la Enfermedad , Humanos , Entrevista Psicológica , Masculino , Análisis Multivariante , Índice de Severidad de la Enfermedad
5.
Mol Psychiatry ; 17(4): 433-44, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21423239

RESUMEN

The heritable component to attempted and completed suicide is partly related to psychiatric disorders and also partly independent of them. Although attempted suicide linkage regions have been identified on 2p11-12 and 6q25-26, there are likely many more such loci, the discovery of which will require a much higher resolution approach, such as the genome-wide association study (GWAS). With this in mind, we conducted an attempted suicide GWAS that compared the single-nucleotide polymorphism (SNP) genotypes of 1201 bipolar (BP) subjects with a history of suicide attempts to the genotypes of 1497 BP subjects without a history of suicide attempts. In all, 2507 SNPs with evidence for association at P<0.001 were identified. These associated SNPs were subsequently tested for association in a large and independent BP sample set. None of these SNPs were significantly associated in the replication sample after correcting for multiple testing, but the combined analysis of the two sample sets produced an association signal on 2p25 (rs300774) at the threshold of genome-wide significance (P=5.07 × 10(-8)). The associated SNPs on 2p25 fall in a large linkage disequilibrium block containing the ACP1 (acid phosphatase 1) gene, a gene whose expression is significantly elevated in BP subjects who have completed suicide. Furthermore, the ACP1 protein is a tyrosine phosphatase that influences Wnt signaling, a pathway regulated by lithium, making ACP1 a functional candidate for involvement in the phenotype. Larger GWAS sample sets will be required to confirm the signal on 2p25 and to identify additional genetic risk factors increasing susceptibility for attempted suicide.


Asunto(s)
Trastorno Bipolar/genética , Trastorno Bipolar/psicología , Predisposición Genética a la Enfermedad/genética , Estudio de Asociación del Genoma Completo/estadística & datos numéricos , Proteínas Tirosina Fosfatasas/genética , Proteínas Proto-Oncogénicas/genética , Intento de Suicidio/psicología , Encéfalo/metabolismo , Estudios de Casos y Controles , Femenino , Estudio de Asociación del Genoma Completo/métodos , Genotipo , Humanos , Masculino , Polimorfismo de Nucleótido Simple , Proteínas Tirosina Fosfatasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo
6.
Am J Med Genet B Neuropsychiatr Genet ; 153B(2): 549-553, 2010 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-19691043

RESUMEN

The Reelin gene (RELN) encodes a secretory glycoprotein critical for brain development and synaptic plasticity. Post-mortem studies have shown lower Reelin protein levels in the brains of patients with schizophrenia and bipolar disorder (BP) compared with controls. In a recent genome-wide association study of schizophrenia, the strongest association was found in a marker within RELN, although this association was seen only in women. In this study, we investigated whether genetic variation in RELN is associated with BP in a large family sample. We genotyped 75 tagSNPs and 6 coding SNPs in 1,188 individuals from 318 nuclear families, including 554 affected offspring. Quality control measures, transmission-disequilibrium tests (TDTs), and empirical simulations were performed in PLINK. We found a significant overtransmission of the C allele of rs362719 to BP offspring (OR = 1.47, P = 5.9 x 10(-4)); this withstood empirical correction for testing of multiple markers (empirical P = 0.048). In a hypothesis-driven secondary analysis, we found that the association with rs362719 was almost entirely accounted for by overtransmission of the putative risk allele to affected females (OR(Female) = 1.79, P = 8.9 x 10(-5) vs. OR(Male) = 1.12, P = 0.63). These results provide preliminary evidence that genetic variation in RELN is associated with susceptibility to BP and, in particular, to BP in females. However, our findings should be interpreted with caution until further replication and functional assays provide convergent support.


Asunto(s)
Trastorno Bipolar/genética , Moléculas de Adhesión Celular Neuronal/genética , Proteínas de la Matriz Extracelular/genética , Proteínas del Tejido Nervioso/genética , Serina Endopeptidasas/genética , Alelos , Salud de la Familia , Femenino , Marcadores Genéticos , Genotipo , Humanos , Masculino , Modelos Genéticos , Neuronas/metabolismo , Control de Calidad , Proteína Reelina , Factores de Riesgo , Esquizofrenia/genética , Factores Sexuales
7.
Mol Psychiatry ; 14(3): 261-8, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18180755

RESUMEN

The FKBP5 gene product forms part of a complex with the glucocorticoid receptor and can modulate cortisol-binding affinity. Variations in the gene have been associated with increased recurrence of depression and with rapid response to antidepressant treatment. We sought to determine whether common FKBP5 variants confer risk for bipolar disorder. We genotyped seven tag single-nucleotide polymorphisms (SNPs) in FKBP5, plus two SNPs previously associated with illness, in 317 families with 554 bipolar offspring, derived primarily from two studies. Single marker and haplotypic analyses were carried out with FBAT and EATDT employing the standard bipolar phenotype. Association analyses were also conducted using 11 disease-related variables as covariates. Under an additive genetic model, rs4713902 showed significant overtransmission of the major allele (P=0.0001), which was consistent across the two sample sets (P=0.004 and 0.006). rs7757037 showed evidence of association that was strongest under the dominant model (P=0.001). This result was consistent across the two datasets (P=0.017 and 0.019). The dominant model yielded modest evidence for association (P<0.05) for three additional markers. Covariate-based analyses suggested that genetic variation within FKBP5 may influence attempted suicide and number of depressive episodes in bipolar subjects. Our results are consistent with the well-established relationship between the hypothalamic-pituitary-adrenal (HPA) axis, which mediates the stress response through regulation of cortisol, and mood disorders. Ongoing whole-genome association studies in bipolar disorder and major depression should further clarify the role of FKBP5 and other HPA genes in these illnesses.


Asunto(s)
Trastorno Bipolar/genética , Predisposición Genética a la Enfermedad , Proteínas de Unión a Tacrolimus/genética , Trastorno Bipolar/fisiopatología , Estudios de Cohortes , Haplotipos , Humanos , Sistema Hipotálamo-Hipofisario/fisiopatología , Desequilibrio de Ligamiento , Trastornos del Humor/genética , Trastornos del Humor/fisiopatología , Linaje , Sistema Hipófiso-Suprarrenal/fisiopatología , Polimorfismo de Nucleótido Simple
8.
Mol Psychiatry ; 12(7): 630-9, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17505464

RESUMEN

Despite compelling evidence that genetic factors contribute to bipolar disorder (BP), attempts to identify susceptibility genes have met with limited success. This may be due to the genetic heterogeneity of the disorder. We sought to identify susceptibility loci for BP in a genome-wide linkage scan with and without clinical covariates that might reflect the underlying heterogeneity of the disorder. We genotyped 428 subjects in 98 BP families at the Center for Inherited Disease Research with 402 microsatellite markers. We first carried out a non-parametric linkage analysis with MERLIN, and then reanalyzed the data with LODPAL to incorporate clinical covariates for age at onset (AAO), psychosis and comorbid anxiety. We sought to further examine the top findings in the covariate analysis in an independent sample of 64 previously collected BP families. In the non-parametric linkage analysis, three loci were nominally significant under a narrow diagnostic model and seven other loci were nominally significant under a broader model. The top findings were on chromosomes 2q24 and 3q28. The covariate analyses yielded additional evidence for linkage on 3q28 with AAO in the primary and independent samples. Although none of the linked loci were genome-wide significant, their congruence with prior results and, for the covariate analyses, their identification in two separate samples increases the likelihood that they are true positives and deserve further investigation. These findings further demonstrate the value of considering clinical features that may reflect the underlying heterogeneity of disease in order to facilitate gene mapping.


Asunto(s)
Trastorno Bipolar/genética , Cromosomas Humanos Par 2/genética , Cromosomas Humanos Par 3/genética , Ligamiento Genético , Predisposición Genética a la Enfermedad/genética , Edad de Inicio , Trastorno Bipolar/clasificación , Mapeo Cromosómico , Humanos , Trastornos del Humor/clasificación , Trastornos del Humor/genética , Linaje , Estadísticas no Paramétricas
9.
Acta Crystallogr B ; 61(Pt 5): 511-27, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16186652

RESUMEN

Following the interest generated by two previous blind tests of crystal structure prediction (CSP1999 and CSP2001), a third such collaborative project (CSP2004) was hosted by the Cambridge Crystallographic Data Centre. A range of methodologies used in searching for and ranking the likelihood of predicted crystal structures is represented amongst the 18 participating research groups, although most are based on the global minimization of the lattice energy. Initially the participants were given molecular diagrams of three molecules and asked to submit three predictions for the most likely crystal structure of each. Unlike earlier blind tests, no restriction was placed on the possible space group of the target crystal structures. Furthermore, Z' = 2 structures were allowed. Part-way through the test, a partial structure report was discovered for one of the molecules, which could no longer be considered a blind test. Hence, a second molecule from the same category (small, rigid with common atom types) was offered to the participants as a replacement. Success rates within the three submitted predictions were lower than in the previous tests - there was only one successful prediction for any of the three ;blind' molecules. For the ;simplest' rigid molecule, this lack of success is partly due to the observed structure crystallizing with two molecules in the asymmetric unit. As in the 2001 blind test, there was no success in predicting the structure of the flexible molecule. The results highlight the necessity for better energy models, capable of simultaneously describing conformational and packing energies with high accuracy. There is also a need for improvements in search procedures for crystals with more than one independent molecule, as well as for molecules with conformational flexibility. These are necessary requirements for the prediction of possible thermodynamically favoured polymorphs. Which of these are actually realised is also influenced by as yet insufficiently understood processes of nucleation and crystal growth.


Asunto(s)
Cristalografía por Rayos X/métodos , Algoritmos , Química/métodos , Simulación por Computador , Bases de Datos Factuales , Bases de Datos de Proteínas , Modelos Químicos , Conformación Molecular , Estructura Molecular , Método de Montecarlo , Conformación Proteica , Pliegue de Proteína , Programas Informáticos , Termodinámica
10.
Exp Clin Endocrinol Diabetes ; 112(7): 356-63, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15239020

RESUMEN

Deformation of the bone matrix by mechanical strain causes fluid shifts within the osteocytic canaliculi which affect osteocytic cell metabolism. We applied low fluid shear (1 - 63 micro Pa for 10 - 48 h) to human osteoblastic cells (HOB) in vitro to study its impact on cell proliferation and differentiated functions. Proteins involved in translating the physical force into a cellular response were characterised. Low fluid shear stress stimulated proliferation of HOB 1.2-fold when stress was applied intermittently for 24 h. Shear stress also increased differentiated cellular properties such as alkaline phosphatase (ALP) activity (121 % of control), fibronectin (FN) and fibronectin receptor (FNR) expression (290 % and 200 %, respectively). Prostaglandin E (2) (PGE (2)) and TGFbeta1 release into the medium were significantly stimulated when shear stress was applied for 6 - 12 h and 24 - 48 h, respectively. TGFbeta1 + 2 neutralising antibodies or the presence of indomethacine inhibited the mitogenic effect of fluid shear and reduced ALP activity to its control level. Furthermore, TGFbeta treatment induced a dose-dependent increase in FN and FNR expression. Therefore, fluid shear stress of low magnitude (a) suffices to affect HOB metabolism and (b) regulates anchorage of HOB via FN and FNR by stimulating osteoblastic PGE (2) and TGFbeta secretion.


Asunto(s)
Moléculas de Adhesión Celular/biosíntesis , División Celular , Osteoblastos/citología , Osteoblastos/fisiología , Reología , Factor de Crecimiento Transformador beta/biosíntesis , Anciano , Fosfatasa Alcalina/metabolismo , Anticuerpos/farmacología , Western Blotting , Moléculas de Adhesión Celular/metabolismo , Diferenciación Celular , Células Cultivadas , Dinoprostona/metabolismo , Fibronectinas/análisis , Fibronectinas/biosíntesis , Humanos , Integrina alfa5beta1/análisis , Integrina alfa5beta1/biosíntesis , Persona de Mediana Edad , Factor de Crecimiento Transformador beta/inmunología , Factor de Crecimiento Transformador beta/metabolismo , Factor de Crecimiento Transformador beta/farmacología , Factor de Crecimiento Transformador beta1 , Factor de Crecimiento Transformador beta2
11.
Chemistry ; 6(19): 3508-16, 2000 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-11072815

RESUMEN

The formation of a sulfuranyl radical intermediate followed by methyl transfer to the nickel(I) center of coenzyme F430 and generation of the disulfide has been proposed as a possible mechanism for the formation of methane catalyzed by methyl coenzyme M reductase in methanogenic archaea. In order to test this hypothesis, a sterically shielded, bifunctional model substrate that contained a methyl thioether and a sulfhydryl functional group, which could form a five-membered cyclic sulfuranyl radical according to the postulated mechanism, was synthesized. The corresponding thiolate reacted with Ni(II) salts to give a diamagnetic, square-planar Ni(II) dithiolate complex, which was characterized by X-ray diffraction. Upon irradiation of this complex with light of lambda > 300 nm, methane and the cyclic disulfide were formed, whereas irradiation of the thiolate in the absence of nickel gave only traces of methane and no cyclic disulfide. The observed products are consistent with the postulated mechanism via a sulfuranyl radical, and the role of light is interpreted as the formation of a Ni(I)/thiyl radical pair upon excitation of a charge-transfer band of the Ni(II) dithiolate. In the presence of a large excess of thiolate, the diamagnetic complex was transformed into a paramagnetic, five- or six-coordinate complex that proved to be more active in the generation of both methane and the cyclic disulfide, than the square-planar diamagnetic dithiolate.


Asunto(s)
Archaea/metabolismo , Metano/metabolismo , Níquel/química , Compuestos de Sulfhidrilo/química , Sulfuros/química
12.
Acta Crystallogr B ; 56(Pt 4): 697-714, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10944263

RESUMEN

A collaborative workshop was held in May 1999 at the Cambridge Crystallographic Data Centre to test how well currently available methods of crystal structure prediction perform when given only the atomic connectivity for an organic compound. A blind test was conducted on a selection of four compounds and a wide range of methodologies representing, the principal computer programs currently available were used. There were 11 participants who were allowed to propose at most three structures for each compound. No program gave consistently reliable results. However, seven proposed structures were close to an experimental one and were classified as "correct". One compound occurred in two polymorphs, but only one form was predicted correctly among the calculated structures. The basic problem with lattice energy based methods of crystal structure prediction is that many structures are found within a few kJ mol(-1) of the global minimum. The fine detail of the force-field methodology and parametrization influences the energy ranking within each method. Nevertheless, present methods may be useful in providing a set of structures as possible polymorphs for a given molecular structure.

13.
Vox Sang ; 70(3): 139-43, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8740004

RESUMEN

Among 47 blood donors tested positive with HCV EIA 2.0 Abbott, 27 (57.4%) also reacted with four ¿third-generation' EIAs. The presence of anti-HCV antibodies was confirmed with 3 different immunoblot assays in 16 of 27 sera (34.0%) while 10 samples (21.3%) had indeterminate profile with antibodies usually directed against structural core antigen. Anti-HCV core IgM response was found in 12 of 47 sera (25.5%) and HCV viremia detected by the polymerase chain reaction (PCR) procedure was observed in 15 samples (31.9%). A comparative study of the different markers confirmed a good correlation between a strong antibody response in EIAs and immunoblot assays and the presence of HCV RNA in the serum; only 2 immunoblot indeterminate samples were PCR positive. An association was observed between IgM antibodies against "core' epitopes and HCV RNA carriage: all IgM-positive sera were found positive by PCR. However, the direct detection of viral genome remains the best method for identifying HCV carriers in the blood donor population.


Asunto(s)
Donantes de Sangre , Hepatitis C/epidemiología , Adulto , Alanina Transaminasa/sangre , Femenino , Hepatitis C/genética , Hepatitis C/inmunología , Anticuerpos contra la Hepatitis C/análisis , Humanos , Técnicas para Inmunoenzimas , Técnicas de Inmunoadsorción , Masculino , Reacción en Cadena de la Polimerasa , ARN Viral/análisis , Juego de Reactivos para Diagnóstico
14.
Nouv Rev Fr Hematol (1978) ; 36 Suppl 2: S123-8, 1994 Jul.
Artículo en Francés | MEDLINE | ID: mdl-7971261

RESUMEN

The quality tests made during the preparation of labile blood products permit to validate the product and to make sure the making procedures are applied properly. The labile blood products have to correspond to a number of standards set by a ministerial order. It is thus necessary to check the manufacturing unit of some products. On account of the original technology of Cell-Dyn 3500 which associates methods of impedance variation measure analysis and flow cytometric technique analysis on non-marked cells, and of its veterinary modulus permitting counting in extreme values, it seemed to be worth being evaluated in a blood bank quality control laboratory. Linearity was studied from a range of dilutions obtained from high value samples prepared by the centrifugation of blood bags and collection of the buffy coat by Optipress system. The study was performed on 22 samples. The linearity in the counting of red cells, white cells, platelets and haematocrit was measured. Intersample contamination was measured. It focused on the values of platelets and white cells. A sample of high cell concentration prepared in the condition mentioned above and a white cell-reduced blood concentrate were used. The study of repeatability was done by treating 20 times three samples covering a wide range of values of the different parameters of cell numeration. The linearity concerning parameters and the range of the values studied are good (example: from 10 to 3000 10(9)/l for platelets). Contamination is low for white cells and non appreciable for platelets. Repeatability shows excellent variation coefficients.


Asunto(s)
Autoanálisis/instrumentación , Hematología/instrumentación , Artefactos , Autoanálisis/normas , Estudios de Evaluación como Asunto , Hematología/normas , Humanos , Recuento de Leucocitos , Modelos Lineales , Recuento de Plaquetas , Reproducibilidad de los Resultados
16.
J Lab Clin Med ; 119(1): 52-6, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1727907

RESUMEN

Two peptides corresponding to the sequence of platelet glycoprotein IIIa between serine 27 and arginine 37 were synthesized and used to produce monoclonal antibodies. These two synthetic peptides were identical except for a single substitution at position 33, where a Pro/Leu polymorphism was shown to occur in human platelets and was predicted to be responsible for the P1A1-P1A2 alloantigen system (Newman et al., J. Clin Invest 1989:83:1778-81). Two monoclonal antibodies named 3C1 for the anti-"P1A1 peptide" and AD3 for the anti-"P1A2 peptide" were characterized. These monoclonal antibodies interacted with the two allelic forms of the reduced glycoprotein IIIa. They were used to type P1A1 and P1A2 homozygote as well as heterozygote platelets. Thus these two immunoprobes confirm that the Pro-Leu substitution is associated with the P1A1-P1A2 alloantigenic system. Although they interact only with reduced glycoprotein IIIa, these antibodies can be used to design simple tests for the typing of the P1A status of patients.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Antígenos de Plaqueta Humana/inmunología , Isoantígenos/inmunología , Glicoproteínas de Membrana Plaquetaria/inmunología , Secuencia de Aminoácidos , Animales , Formación de Anticuerpos , Especificidad de Anticuerpos , Antígenos de Plaqueta Humana/clasificación , Antígenos de Plaqueta Humana/genética , Plaquetas/fisiología , Heterocigoto , Homocigoto , Humanos , Isoantígenos/genética , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Glicoproteínas de Membrana Plaquetaria/genética
17.
Am J Orthod Dentofacial Orthop ; 99(6): 533-42, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2038973

RESUMEN

A three-dimensional morphometric method was used to evaluate progressive changes in shape and size of recovering dental and periodontal tissues after orthodontic loading. In 35 female rats weighing 212 +/- 4 gm, loads of 19.7 +/- 1.6 gm generated by closed-coil springs were applied for 2 weeks to the shortened lower left incisor. The rats were killed in groups of five at 0, 1, 3, 5, 7, 9, and 10 weeks (groups 0-w to 10-w) after the springs were removed. A group of rats with normal incisors (group C-1) and one with five incisors that had been continually shortened for 10 weeks (group C-2) served as controls for groups 0-w and 10-w, respectively. Width, area, and volume of the tooth and enamel-bordering periodontal ligament (e-PDL) and cementum-bordering PDL (c-PDL) were measured. After 2 weeks of loading (group 0-w), the volume of the compressed e-PDL had decreased by 22%, and the volume of the stretched c-PDL had increased by 72%, suggesting that bone apposition lags behind the rate of tooth movement. During the recovery period, the dental and periodontal parameters tended toward a gradual return to control (C-2) values, although at the end of 10 weeks many still lagged significantly behind the controls. Recovery was slowed by repeated reversals at different sites in the various groups. The ability of the preloaded incisor to adjust to changes in occlusal function was lastingly impaired.


Asunto(s)
Ligamento Periodontal/patología , Técnicas de Movimiento Dental , Diente/patología , Animales , Femenino , Incisivo , Estudios Longitudinales , Mandíbula/patología , Mandíbula/fisiopatología , Modelos Biológicos , Odontometría , Aparatos Ortodóncicos , Ligamento Periodontal/fisiopatología , Ratas , Ratas Endogámicas , Estrés Mecánico , Factores de Tiempo , Diente/fisiopatología , Erupción Dental/fisiología , Técnicas de Movimiento Dental/instrumentación , Raíz del Diente/patología , Raíz del Diente/fisiopatología
18.
Vox Sang ; 61(3): 190-5, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1807060

RESUMEN

The clinical course and laboratory findings of a patient with autoimmune haemolytic anaemia due to anti-phospholipid antibodies and secondary to a systemic lupus erythematosus-like syndrome are described. IgG and IgM with anti-phospholipid activity coexisted in both sera and acid eluates prepared from the patient's red cells, as demonstrated by ELISA using a panel of anionic and neutral phospholipids. The anti-erythrocyte binding activity of eluted autoantibodies, determined by a radioactive antiglobulin technique, was totally inhibited by absorption with phospholipid micelles. The patient's serum also contained an IgM warm haemolysin detectable with enzyme-treated cells only, as well as anti-C, -E and -S alloantibodies.


Asunto(s)
Anemia Hemolítica Autoinmune/inmunología , Síndrome Antifosfolípido/sangre , Autoanticuerpos/inmunología , Fosfolípidos/inmunología , Anemia Hemolítica Autoinmune/sangre , Especificidad de Anticuerpos/inmunología , Femenino , Humanos , Persona de Mediana Edad
19.
Environ Pollut ; 68(3-4): 275-92, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-15092177

RESUMEN

Gas exchange was characterized in one- and two year-old spruce (Picea abies L. Karst.) and fir seedlings (Abies alba Mill.) which had been exposed to low levels of ozone, sulfur dioxide and simulated rain or a combination of all three variables in open top chambers from 1983 through 1988. The gas exchange measurements were carried out in March 1988 at the end of the five year experiment. The twigs examined did not exhibit any visible sign of injury, specifically no differences were apparent between trees under the treatments of simulated acidic rain at pH 5.0 and pH 4.0. The study of carbon dioxide response curves showed different effects of the pollutants on the tree species. One-Year-old spruce needles treated with O(3) and simulated acidic precipitation pH 4.0 showed noticeable reduction of net photosynthetic rate. Exposure to the combination O(3) and SO(2) at pH 4.0 resulted in a significant depression of photosynthesis in two-year-old needles Transpiration rate was not decreased to a similar extent. No changes either in photosynthesis or transpiration were found in spruce under fumigation with SO(2) alone. These results indicate that ozone is the principal cause of changes in photosynthetic performance of spruce. It alters mesophyll response rather than reducing stomatal conductance. The specific changes that occur in the mesophyll could be diagnosed as inactivation of a carbon fixing enzyme as well as damage of the electron transport system. Fir seem to be more tolerant to ozone. No changes in photosynthesis and transpiration following exposure to O(3) alone were found. However, SO(2) fumigation, alone or in combination with O(3), resulted in a marked decrease of photosynthetic performance. Particularly, carboxylation efficiency and also maximum carboxylation velocity were depressed indicating a reduction in carbon fixing enzyme activity. No differences between single and combined fumigation treatments regarding these variables were determined. However, parameters measured to determine changes in electron transport rate showed a higher depression in the presence of both pollutants. Transpiration also was reduced by SO(2).

20.
Artículo en Inglés | MEDLINE | ID: mdl-3190862
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