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1.
IEEE Trans Appl Supercond ; 29(5)2019 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-31360051

RESUMEN

Readout of a large, spacecraft-based array of superconducting transition-edge sensors (TESs) requires careful management of the layout area and power dissipation of the cryogenic-circuit components. We present three optimizations of our time- (TDM) and code-division-multiplexing (CDM) systems for the X-ray Integral Field Unit (X-IFU), a several-thousand-pixel-TES array for the planned Athena-satellite mission. The first optimization is a new readout scheme that is a hybrid of CDM and TDM. This C/TDM architecture balances CDM's noise advantage with TDM's layout compactness. The second is a redesign of a component: the shunt resistor that provides a dc-voltage bias to the TESs. A new layout and a thicker Pd-Au resistive layer combine to reduce this resistor's area by more than a factor of 5. Third, we have studied the power dissipated by the first-stage SQUIDs (superconducting quantum-interference devices) and the readout noise versus the critical current of the first-stage SqUIDs. As a result, the X-IFU TDM and C/TDM SQUIDs will have a specified junction critical current of 5 µA. Based on these design optimizations and TDM experiments described by Durkin, et al. (these proceedings), TDM meets all requirements to be X-IFU's backup-readout option. Hybrid C/TDM is another viable option that could save spacecraft resources.

2.
Artículo en Inglés | MEDLINE | ID: mdl-31160861

RESUMEN

Time-division multiplexing (TDM) is the backup readout technology for the X-ray Integral Field Unit (X-IFU), a 3,168-pixel X-ray transition-edge sensor (TES) array that will provide imaging spectroscopy for ESA's Athena satellite mission. X-0IFU design studies are considering readout with a multiplexing factor of up to 40. We present data showing 40-row TDM readout (32 TES rows + 8 repeats of the last row) of TESs that are of the same type as those being planned for X-IFU, using measurement and analysis parameters within the ranges specified for X-IFU. Singlecolumn TDM measurements have best-fit energy resolution of (1.91 ± 0.01) eV for the Al Kα complex (1.5 keV), (2.10 ± 0.02) eV for Ti Kα (4.5 keV), (2.23 ± 0.02) eV for Mn Kα (5.9 keV), (2.40 ± 0.02) eV for Co Kα (6.9 keV), and (3.44 ± 0.04) eV for Br Kα (11.9 keV). Three-column measurements have best-fit resolution of (2.03 ± 0.01) eV for Ti Kα and (2.40 ± 0.01) eV for Co Kα. The degradation due to the multiplexed readout ranges from 0.1 eV at the lower end of the energy range to 0.5 eV at the higher end. The demonstrated performance meets X-IFU's energy-resolution and energy-range requirements. True 40-row TDM readout, without repeated rows, of kilopixel scale arrays of X-IFU-like TESs is now under development.

3.
Xenobiotica ; 44(1): 17-27, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23883428

RESUMEN

1. It has previously been demonstrated that metabolism of drugs via a single enzymatic pathway, particularly CYP3A4, is associated with increased risk for drug-drug interactions (DDI). Quantitative experimental systems as well as integrated prediction models to assess such risk during the preclinical phase are highly warranted. 2. The present study was designed to systematically investigate the performance of human cryopreserved hepatocytes in suspension to predict fraction metabolized via CYP3A (fmCYP3A) by assessing the ketoconazole sensitive intrinsic clearance (CLint) for five prototypical CYP3A substrates with varying degree of CYP3A dependent CLint in twelve individual hepatocyte batches. 3. We demonstrate that in contrast to well predicted mean hepatic metabolic clearance (CLH) and mean fmCYP3A data, the variability in CYP3A contribution for compounds having multiple metabolic pathways cannot be predicted from inhibition experiments using ketoconazole as inhibitor. Instead, data in the present paper indicate that the variability is larger after inhibition of CYP3A for compounds having multiple metabolic pathways. 4. It is therefore recommended to estimate the average CLint and fmCYP3A for a given test compound in a series (n = 10) of individual human hepatocyte batches.


Asunto(s)
Criopreservación/métodos , Citocromo P-450 CYP3A/metabolismo , Interacciones Farmacológicas/fisiología , Hepatocitos/metabolismo , Redes y Vías Metabólicas/fisiología , Modelos Biológicos , Preparaciones Farmacéuticas/metabolismo , Cromatografía Líquida de Alta Presión , Humanos , Espectrometría de Masas
4.
Rev Med Interne ; 42(8): 535-540, 2021 Aug.
Artículo en Francés | MEDLINE | ID: mdl-33323294

RESUMEN

INTRODUCTION: The prescription of proton pump inhibitors (PPIs) seems excessive. Taken over the long term, PPIs can cause serious side effects. It therefore turns out to be justified to suspend treatments whose expected benefit seems too low compared to the risks involved : it is deprescription. The objective of this study is to assess a process for the deprescription of PPIs in a hospital internal medicine department. METHOD: After collegial deliberation, an algorithm for assisting in the deprescription of PPIs was validated. If necessary, the PPI was phased out over 1 month. A telephone follow-up at 1, 2 and 3 months was carried out in order to assess the maintenance of deprescription and the occurrence of digestive symptoms. The evaluation criteria were the rate of deprescription and the rate of maintenance of deprescription at 3 months following reports from patients, their caregivers or a family member. RESULTS: 105 patients with a mean age of 72 years were included over a period of 21 weeks, and in 31 cases (29%), deprescription was performed. After 3 months of follow-up, there was 71% maintenance of deprescription. Three patients were lost to follow-up and 6 patients resumed PPI. CONCLUSION: The approach undertaken resulted in the suspension of PPI intake in almost 3 out of 10 cases. This result was maintained at least three months for a large majority of patients. It will be interesting to continue this process and extend the monitoring over longer periods, in order to ensure that PPI de-prescription is maintained in the long term.


Asunto(s)
Medicina Interna , Inhibidores de la Bomba de Protones , Anciano , Algoritmos , Humanos , Prescripciones
5.
Rev Med Interne ; 42(2): 79-85, 2021 Feb.
Artículo en Francés | MEDLINE | ID: mdl-33160706

RESUMEN

INTRODUCTION: Patients admitted from emergency units represent a large portion of the population in internal medicine departments. The aim of this study is to identify characteristics of patients and organization of these departments. METHODS: Between June 29th and July 26th 2015, voluntary internal medicine departments from the SiFMI group prospectively filled anonymized internet forms to collect data of each patients admitted in their ward from emergency units, during seven consecutive days. RESULTS: Three hundred and sixty-five patients from emergency departments were admitted in 18 internal medicine inpatients departments, totalling 1100 beds and 33,530 annual stays, 56% of them for emergency units inpatients. Mean age was 68 years, 54% were women, mean Charlson score was 2.6 and 44% of the patients took at least three drugs. Main causes of hospitalization were infectious (29%) and neurological (17%) diseases. Mean length of stay was 9.2 days. The medical team was composed by a median value of 4,5 [2,75-6,25] senior full-time equivalents, 86% were internists. Each department except one received residents, two third of them were from general medicine. CONCLUSION: This study highlights a high organizational variability among internal medicine departments and patients, and sets internal medicine as a specialty with a great capacity to achieve an integrative/comprehensive management of patients and to offer a comprehensive basis for physicians in training.


Asunto(s)
Servicio de Urgencia en Hospital , Medicina Interna , Anciano , Estudios Transversales , Femenino , Hospitalización , Hospitales , Humanos
6.
Int J Clin Pract ; 64(1): 55-60, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18479364

RESUMEN

OBJECTIVE: The aim of our study was to evaluate the diagnostic contribution of (18)F-fluoro-deoxyglucose ((18)F-FDG)-positron emission tomography (PET)/computed tomography (CT) in patients with fever of unknown origin (FUO) or unexplained prolonged inflammatory syndrome (UPIS) in real life. PATIENTS AND METHODS: We performed a retrospective study including 14 patients with FUO or UPIS hospitalised in our institution (Strasbourg University Hospital, France) between January 2005 and July 2006. (18)F-FDG-PET/CT was considered helpful when abnormal results allowed an accurate diagnosis. RESULTS: (18)F-FDG-PET/CT was helpful in half the patients (7/14) for final diagnosis. A diagnosis was reached in 87.5% of the patients (7/8) with an abnormal (18)F-FDG-PET/CT but only in 50% of the patients (3/6) with a normal (18)F-FDG-PET/CT. Conventional chest and abdominal CT was performed in 13 patients before ordering (18)F-FDG-PET/CT. We considered that (18)F-FDG-PET/CT was essential to establish the final diagnosis in only 23% of the patients (3/13) since neither chest nor abdominal CT identified abnormalities consistent with the final diagnosis. However, among the three patients, two were diagnosed with large vessel vasculitis and one patient with local prosthetic infection. CONCLUSIONS: Our study supports the potential interest of (18)F-FDG-PET/CT in the diagnostic workup of FUO and UPIS as it helped establish a fine diagnosis in half of the cases. However, (18)F-FDG-PET/CT appeared to be essential to the final diagnosis in only 23% of the cases. In our opinion, this protocol should be performed as a second level test, especially when conventional CT is normal or is unable to discriminate between active and silent lesions.


Asunto(s)
Fiebre de Origen Desconocido/etiología , Fluorodesoxiglucosa F18 , Inflamación/diagnóstico , Tomografía de Emisión de Positrones/métodos , Radiofármacos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Sensibilidad y Especificidad , Síndrome
7.
Plant Cell Environ ; 32(10): 1310-23, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19453481

RESUMEN

Isotopic labelling experiments were conducted to assess relationships among (13)C of recently assimilated carbon (deltaC(A)), foliage respiration (deltaC(F)), soluble carbohydrate (deltaC(SC)), leaf waxes (deltaC(LW)) and bulk organic matter (deltaC(OM)). Slash pine, sweetgum and maize were grown under (13)C depleted CO(2) to label biomass and then placed under ambient conditions to monitor the loss of label. In pine and sweetgum, deltaC(F) of labelled plants (approximately -44 and -35 per thousand, respectively) rapidly approached control values but remained depleted by approximately 4-6 per thousand after 3-4 months. For these tree species, no or minimal label was lost from deltaC(SC), deltaC(LW) and deltaC(OM) during the observation periods. deltaC(F) and deltaC(SC) of labelled maize plants rapidly changed and were indistinguishable from controls after 1 month, while deltaC(LW) and deltaC(OM) more slowly approached control values and remained depleted by 2-6 per thousand. Changes in deltaC(F) in slash pine and sweetgum fit a two-pool exponential model, with the fast turnover metabolic pool (approximately 3-4 d half-life) constituting only 1-2% of the total. In maize, change in deltaC(F) fits a single pool model with a half-life of 6.4 d. The (13)C of foliage respiration and biochemical pools reflect temporally integrated values of deltaC(A), with change in isotopic composition dampened by the size of metabolic carbon reserves and turnover rates.


Asunto(s)
Dióxido de Carbono/metabolismo , Carbono/metabolismo , Hojas de la Planta/metabolismo , Biomasa , Carbohidratos/análisis , Isótopos de Carbono/metabolismo , Liquidambar/metabolismo , Modelos Químicos , Pinus/metabolismo , Especificidad de la Especie , Factores de Tiempo , Ceras/análisis , Zea mays/metabolismo
8.
Toxicol Appl Pharmacol ; 235(1): 86-96, 2009 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-19118567

RESUMEN

It is important to investigate the induction of cytochrome P450 (CYP) enzymes by drugs. The most relevant end point is enzyme activity; however, this requires many cells and is low throughput. We have compared the CYP1A, CYP2B and CYP3A induction response to eight inducers in rat and human hepatocytes using enzyme activities (CYP1A2 (ethoxyresorufin), 2B (benzoxyresorufin for rat and bupropion for human) and CYP3A (testosterone)) and Taqman Low Density Array (TLDA) analysis. There was a good correlation between the induction of CYP1A2, CYP2B6 and CYP3A4 enzyme activities and mRNA expression in human hepatocytes. In contrast, BROD activities and mRNA expression in rat hepatocytes correlated poorly. However, bupropion hydroxylation correlated well with Cyp2b1 expression in rat hepatocytes. TLDA analysis of a panel of mRNAs encoding for CYPs, phase 2 enzymes, nuclear receptors and transporters revealed that the main genes induced by the 8 compounds tested were the CYPs. AhR ligands also induced UDP-glucuronosyltransferases and glutathione S-transferases in rat and human hepatocytes. The transporters, MDR1, MDR3 and OATPA were the only transporter genes significantly up-regulated in human hepatocytes. In rat hepatocytes Bsep, Mdr2, Mrp2, Mrp3 and Oatp2 were up-regulated. We could then show a good in vivo:in vitro correlation in the induction response of isolated rat hepatocytes and ex-vivo hepatic microsomes for the drug development candidate, EMD392949. In conclusion, application of TLDA methodology to investigate the potential of compounds to induce enzymes in rat and human hepatocytes increases the throughput and information gained from one assay, without reducing the predictive capacity.


Asunto(s)
Sistema Enzimático del Citocromo P-450/metabolismo , Inducción Enzimática/efectos de los fármacos , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , ARN Mensajero/metabolismo , Anciano , Animales , Células Cultivadas , Sistema Enzimático del Citocromo P-450/genética , Humanos , Masculino , ARN Mensajero/genética , Ratas , Ratas Wistar , Regulación hacia Arriba
10.
Rev Med Interne ; 29(12): 1017-23, 2008 Dec.
Artículo en Francés | MEDLINE | ID: mdl-18799245

RESUMEN

Breastfeeding is often contraindicated when drugs are prescribed for a chronic maternal disease. Many of the restrictions are based on theoretical concerns only and may be excessively cautious. An updated review is mandatory. Many antirheumatic drugs can be safely used during lactation: nonsteroidal anti-inflammatory drugs, corticosteroids, sulfasalazine, antimalarial agents. Doubt remains about safety of cochicine or dapsone. Expert opinions still diverge but move on in favor the use of azathioprine, ciclosporin, and even methotrexate. Leflunomide, mycophenolate mofetil and cyclophosphamide are contraindicated. No conclusion can be reached regarding anti-TNF-alpha and rituximab. Current knowledge about drug transfer in breast-milk and cumulative empirical data have expanded the possibilities to allow breastfeeding when the mother is treated with antirheumatic medications. The data provided by pharmaceutical industry should not be the only source of the physician's information in the risk assessment.


Asunto(s)
Antirreumáticos/uso terapéutico , Lactancia Materna , Enfermedades del Tejido Conjuntivo/tratamiento farmacológico , Inmunosupresores/uso terapéutico , Enfermedades Reumáticas/tratamiento farmacológico , Adulto , Antirreumáticos/efectos adversos , Antirreumáticos/farmacología , Femenino , Humanos , Inmunosupresores/efectos adversos , Inmunosupresores/farmacología , Lactante , Recién Nacido , Lactancia/efectos de los fármacos , Medición de Riesgo
11.
Rev Med Interne ; 29(8): 666-8, 2008 Aug.
Artículo en Francés | MEDLINE | ID: mdl-18321612

RESUMEN

We report the case of a young smoker woman who developed a severe acrosyndrome of rapid onset, involving both hands except the thumbs. The angiography showed digital arteritis. Antinuclear antibodies were present at high level. Three months later, a large B cell lymphoma was diagnosed. Complete remission was achieved, but the acrosyndrome persisted with only partial improvement. The antinuclear antibodies disappeared. The paraneoplastic nature of the acrosyndrome is discussed.


Asunto(s)
Arteritis/etiología , Dedos/irrigación sanguínea , Linfoma de Células B/diagnóstico , Síndromes Paraneoplásicos/etiología , Adulto , Angiografía , Femenino , Humanos , Fumar
12.
J Clin Invest ; 93(5): 2093-105, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-7514192

RESUMEN

There is evidence that in certain situations the expressed antibody repertoire is dominated by small subsets of V gene segments. They include fetal, CD5+, and autoantibody-forming B cells as well as low grade B cell malignancies. For instance, inside the V kappa III family of approximately 10 members, only 3 (humkv325, 328, and Vg) are used recurrently for autoantibody production. However, the significance of this recurrence is difficult to interpret without a clear vision of the actual repertoire in normal subjects. To address this, we have sequenced and compared two sets of rearranged V kappa III genes generated by cDNA PCR amplification from a normal newborn, a normal adult, and from CD5+ B cells of the same adult donor. The results show that: (a) only four V kappa III gene segments are used by neonatal and total adult B cells (humkv325, humkv328, Vg, and kv305), humkv325 being overexpressed in both repertoires; (b) there is no significant difference in terms of V kappa III gene usage between the adult and newborn repertoires; (c) regarding the junction regions, there is a favored use of the most 5' JK gene segments (Jk1-Jk2); approximately 20% of the newborn and adult junction sequences was characterized by one or two additional codons, most probably resulting from a nontemplate addition of nucleotides; (d) adult clones, in contrast to most newborn clones, show sequence divergences from prototype sequences with patterns which suggest antigen-driven diversity; (e) regarding the adult CD5+ B cell library, it is most probable that the 78 clones analyzed derived from no more than nine different VK-JK rearrangements. Humkv325 is used by at least six of them, and most of the expressed V genes were in exact or very near germline configuration. Collectively these results suggest that the expressed antibody V kappa III repertoire in the adult represents only a fraction of the potential genetic information and that it resembles the preimmune repertoire of the neonate. The data, which also suggest that the adult peripheral blood CD5+ B cell population may be dominated by a small number of B cell clones, are discussed with regards to the V kappa III usage in pathological situations.


Asunto(s)
Envejecimiento/genética , Reordenamiento Génico de Linfocito B/genética , Genes de Inmunoglobulinas/genética , Región Variable de Inmunoglobulina/genética , Cadenas kappa de Inmunoglobulina/genética , Adulto , Secuencia de Aminoácidos , Antígenos CD/genética , Subgrupos de Linfocitos B/inmunología , Secuencia de Bases , Antígenos CD5 , Células Clonales , Sangre Fetal/citología , Sangre Fetal/inmunología , Biblioteca de Genes , Humanos , Cadenas Ligeras de Inmunoglobulina/genética , Recién Nacido , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Homología de Secuencia de Ácido Nucleico
14.
Rev Med Interne ; 37(1): 50-2, 2016 Jan.
Artículo en Francés | MEDLINE | ID: mdl-26031739

RESUMEN

INTRODUCTION: Bevacizumab is an antibody directed against VEGF-A. It is approved for the treatment of many cancer diseases. Its side effects are currently not well known by physicians. CASE REPORT: A 70-year-old female with metastatic colonic adenocarcinoma was admitted in the intensive care unit because of a coma, four days after having received a combined monthly chemotherapy containing bevacizumab, oxaliplatine, 5 fluorouracil, and folinic acid for the fourth time. On clinical examination, she presented with lower limbs spasticity and hypertension. Etiologic investigations, including cerebral tomodensitometry, cerebrospinal fluid examination, psychotropic drugs urinary testing, and electroencephalogram, were negative. Consciousness improved without any other treatment than nicardipine and urapidil, but the patient was initially confused. Cerebral magnetic resonance imaging showed changes suggestive of posterior reversible encephalopathy syndrome, but also involving frontal lobes. There were additional biological and echocardiographic changes suggestive of cardiac involvement. The patient recovered completely of both cardiac and neurologic manifestations 10 days later. CONCLUSION: Physicians should be aware of cardiovascular adverse effects of bevacizumab. High blood pressure must be treated to avoid more severe complications. When a posterior reversible encephalopathy syndrome occurs, cardiac involvement should be investigated.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Bevacizumab/efectos adversos , Cardiomiopatías/inducido químicamente , Neoplasias del Colon/tratamiento farmacológico , Síndrome de Leucoencefalopatía Posterior/inducido químicamente , Adenocarcinoma/patología , Anciano , Bevacizumab/uso terapéutico , Neoplasias del Colon/patología , Femenino , Humanos
15.
Rev Med Interne ; 36(8): 548-50, 2015 Aug.
Artículo en Francés | MEDLINE | ID: mdl-26045334

RESUMEN

The growing incidence of burn-out syndrome among physicians has become a major concern for public policy. The root causes are not fully understood. We make the assumption that the most powerful cause of their suffering at work is the challenging of physician's practical judgment. Practical judgment is the faculty, which connects knowledge and reason, science and experience, general and individual issues. It lies at the core of medical action and its exercise is closely associated with a pleasure at work. The evolution of medicine, particularly the proliferation of procedures, has a harmful influence on its training and its exercise.


Asunto(s)
Agotamiento Profesional/psicología , Juicio , Medicina , Humanos , Satisfacción en el Trabajo , Placer , Síndrome
16.
Ultramicroscopy ; 150: 1-9, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25463325

RESUMEN

Near-field scanning microwave microscopy offers great potential to facilitate characterization, development and modeling of materials. By acquiring microwave images at multiple frequencies and amplitudes (along with the other modalities) one can study material and device physics at different lateral and depth scales. Images are typically noisy and contaminated by artifacts that can vary from scan line to scan line and planar-like trends due to sample tilt errors. Here, we level images based on an estimate of a smooth 2-d trend determined with a robust implementation of a local regression method. In this robust approach, features and outliers which are not due to the trend are automatically downweighted. We denoise images with the Adaptive Weights Smoothing method. This method smooths out additive noise while preserving edge-like features in images. We demonstrate the feasibility of our methods on topography images and microwave |S11| images. For one challenging test case, we demonstrate that our method outperforms alternative methods from the scanning probe microscopy data analysis software package Gwyddion. Our methods should be useful for massive image data sets where manual selection of landmarks or image subsets by a user is impractical.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Microscopía Electrónica de Transmisión de Rastreo/métodos , Microscopía/métodos , Microondas , Algoritmos , Artefactos , Estudios de Factibilidad , Microscopía de Fuerza Atómica , Programas Informáticos
17.
Arch Neurol ; 44(1): 87-9, 1987 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3800726

RESUMEN

Diagnosis of embolic stroke is based on identification of a source of embolus (SOE) and on neurologic symptoms acknowledged as "clinical criteria." To test the validity of these criteria, we analyzed the symptoms at onset in 193 patients hospitalized after acute cerebral infarction. Patients were grouped according to identification of a cardiac SOE (106 patients), an arterial SOE (38 patients), or no SOE (49 patients). Cross-tabulations demonstrated that only rapidity and loss of consciousness at onset were associated with the presence of a cardiac SOE to a significant degree. Although these symptoms were highly specific for cardiac SOE, they were not sensitive. A distinct clinical neurologic profile from the symptoms and mode of onset was not identified.


Asunto(s)
Embolia y Trombosis Intracraneal/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Cardiopatías/complicaciones , Humanos , Embolia y Trombosis Intracraneal/etiología , Ataque Isquémico Transitorio/diagnóstico , Masculino , Persona de Mediana Edad
18.
Autoimmunity ; 16(3): 215-24, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8003617

RESUMEN

The mechanisms that govern autoantibody production are still under debate. In particular, auto-antibodies can appear as a consequence of a polyclonal activation of B cells or as a consequence of an antigen driven B cell expansion. The molecular analysis of the variable regions of auto-antibodies arising during different clinical situations can help to understand the origin of auto-antibodies. We recently described the main light chain variable regions of polyclonal rheumatoid factors occurring during rheumatoid arthritis and suggested that the mutation pattern of these regions could reflect an antigen driven process. Using the same approach, we now report the molecular analysis of the same light chain variable region containing a VKIII segment of rheumatoid factors originating from a polyclonal activation of B cells during an in vivo Epstein-Barr virus infection, infectious mononucleosis. The cDNA derived from rheumatoid factor synthetizing cells were amplified by two sets of polymerase chain reaction. The amplified products were cloned in M13mp19 phages and sequenced. The nucleotide analysis of the VKIII containing VK regions shows that: 1) the rheumatoid factor activity is associated with the 3 VKIII genes (Kv 325, Kv 328 and Vg) already known to encode for monoclonal and polyclonal rheumatoid factors, 2) there is a preferential use of Kv 328 and Vg, each one of these genes being poorly mutated, 3) the CDR mutation rates of these genes is no higher than the framework mutation rates, 4) there is a restriction of the JK usage; Kv 328 derived gene segments rearrange exclusively with JK1, Vg preferentially rearranges with JK1 and JK4. These results mainly suggest that naturally occurring polyclonal activation of autoreactive B cells produces poorly mutated autoantibodies.


Asunto(s)
Región Variable de Inmunoglobulina/análisis , Cadenas kappa de Inmunoglobulina/análisis , Mononucleosis Infecciosa/inmunología , Factor Reumatoide/química , Adulto , Secuencia de Aminoácidos , Secuencia de Bases , Separación Celular , Citometría de Flujo , Humanos , Región Variable de Inmunoglobulina/genética , Cadenas kappa de Inmunoglobulina/genética , Masculino , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Factor Reumatoide/genética
19.
Arch Ophthalmol ; 102(5): 697-8, 1984 May.
Artículo en Inglés | MEDLINE | ID: mdl-6721755

RESUMEN

Of 60 attacks of ocular toxoplasmosis, in 37 (62%) no apparent macular problems were demonstrated on inspection, in seven (12%) active retinitis was evident within 5 degrees of the umbo, and in seven (12%) some evidence was shown of mild macular edema; severe edema, such as cystoid macular edema, was uncommon.


Asunto(s)
Mácula Lútea/patología , Toxoplasmosis Ocular/patología , Cámara Anterior/patología , Humanos , Cristalino/patología , Luz , Toxoplasmosis Ocular/fisiopatología , Pruebas de Visión , Agudeza Visual , Campos Visuales , Cuerpo Vítreo/patología
20.
Arch Ophthalmol ; 101(3): 458-9, 1983 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6830503

RESUMEN

Sixty-two percent of 975 uveitis patients had a statistically significant elevation in the levels of one or more of three serum immunoglobulins. The percentage of cases of above-normal values was greatest for IgM (43.8%), followed by IgA (34.0%), and then by IgG (11.9%). There was no statistically significant difference in immunoglobulin values obtained for one diagnosis as compared with all others, except for men with HLA-B27. They had a higher percent of elevated IgM values than men with all other diagnoses. Testing for immunoglobulins is of little or no value in the etiologic diagnosis of a single case of uveitis, but may be of value in research studies to better understand its pathogenesis.


Asunto(s)
Inmunoglobulinas/análisis , Uveítis/inmunología , Femenino , Humanos , Inmunoglobulina A/análisis , Inmunoglobulina G/análisis , Inmunoglobulina M/análisis , Masculino
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