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1.
Plant Biol (Stuttg) ; 25(3): 420-432, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36689309

RESUMEN

Mangrove seedlings are subject to natural tidal inundation, while occasional flooding may lead to complete submergence. Complete submergence reduces light availability and limits gas exchange, affecting several plant metabolic processes. The present study focuses on Rhizophora mucronata, a common mangrove species found along the coasts of Thailand and the Malay Peninsula. To reveal response mechanisms of R. mucronata seedlings to submergence, a physiological investigation coupled with proteomic analyses of leaf and root tissues was carried out in plants subjected to 20 days of control (drained) or submerged conditions. Submerged seedlings showed decreased photosynthetic activity, lower stomatal conductance, higher total antioxidant capacity in leaves and higher lipid peroxidation in roots than control plants. At the same time, tissue nutrient ion content displayed organ-specific responses. Proteome analysis revealed a significant change in 240 proteins in the leaves and 212 proteins in the roots. In leaves, most differentially accumulated proteins (DAPs) are associated with nucleic acids, stress response, protein transport, signal transduction, development and photosynthesis. In roots, most DAPs are associated with protein metabolic process, response to abiotic stimulus, nucleic acid metabolism and transport. Our study provides a comprehensive understanding of submergence responses in R. mucronata seedlings. The results suggest that submergence induced multifaceted stresses related to light limitation, oxidative stress and osmotic stress, but the responses are organ specific. The results revealed many candidate proteins which may be essential for survival of R. mucronata under prolonged submergence.


Asunto(s)
Rhizophoraceae , Plantones , Plantones/metabolismo , Rhizophoraceae/metabolismo , Proteómica , Estrés Oxidativo , Fotosíntesis , Hojas de la Planta/metabolismo , Raíces de Plantas/metabolismo
2.
Ann Rheum Dis ; 71(1): 67-70, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21917823

RESUMEN

UNLABELLED: Introduction The early detection of systemic sclerosis (SSc) patients at high risk of developing digital ulcers could allow preventive treatment, with a reduction of morbidity and social costs. In 2009, a quantitative score, the capillaroscopic skin ulcer risk index (CSURI), calculated according to the formula 'D×M/N(2'), was proposed, which was highly predictive of the appearance of scleroderma digital ulcers within 3 months of capillaroscopic evaluation. OBJECTIVES: This multicentre study aims to validate the predictive value and reproducibility of CSURI in a large population of SSc patients. METHODS: CSURI was analysed in 229 unselected SSc patients by nailfold videocapillaroscopy (NVC). All patients were re-evaluated 3 months later with regard to the persistence and/or appearance of new digital ulcers. RESULTS: 57 of 229 patients presented with digital ulcers after 3 months. The receiver operating characteristic curve analysis showed an area under the curve of 0.884 (95% CI 0.835 to 0.922), with specificity and sensitivity of 81.4% (95% CI 74.8 to 86.89) and 92.98% (95% CI 83.0 to 98.0), respectively, at the cut-off value of 2.96. The reproducibility of CSURI was validated on a random sample of 81 patients, with a κ-statistic measure of interrater agreement of 0.8514. CONCLUSIONS: The role of CSURI was confirmed in detecting scleroderma patients with a significantly high risk of developing digital ulcers within the first 3 months from NVC evaluation. CSURI is the only method validated to predict the appearance of digital ulcers and its introduction into routine clinical practice might help optimise the therapeutic strategy of these harmful SSc complications.


Asunto(s)
Angioscopía Microscópica/métodos , Esclerodermia Sistémica/complicaciones , Úlcera Cutánea/etiología , Adulto , Anciano , Algoritmos , Capilares/patología , Diagnóstico Precoz , Métodos Epidemiológicos , Femenino , Dedos/irrigación sanguínea , Humanos , Masculino , Persona de Mediana Edad , Uñas/irrigación sanguínea , Medición de Riesgo/métodos , Piel/irrigación sanguínea , Úlcera Cutánea/diagnóstico
3.
Osteoarthritis Cartilage ; 20(2): 93-101, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22178465

RESUMEN

OBJECTIVE: Total joint replacement has been proposed as an endpoint in disease modifying osteoarthritis drug (DMOAD) randomized clinical trials (RCTs); however, disparities have generated concerns regarding this outcome. A combined Osteoarthritis Research Society International (OARSI)/Outcome Measures in Rheumatology (OMERACT) initiative was launched in 2004 to develop a composite index ['virtual total joint replacement' (VJR)] as a surrogate outcome for osteoarthritis (OA) progression in DMOAD RCTs. Our objective was to evaluate the prevalence of patients fulfilling different thresholds of sustained pain, reduced function, and X-ray change in existing DMOAD RCTs. DESIGN: Post hoc analysis of summary data from the placebo arm of eight DMOAD RCTs. RESULTS: Eight OA RCTs representing 1379 patients were included. Pain was assessed by WOMAC and/or VAS and function by WOMAC and/or Lequesne. Among six knee and two hip studies, 248 (22%) and 132 (51%) patients respectively had X-ray progression [decrease joint space width (JSW) ≥0.5 mm]. The prevalence of patients fulfilling clinical and radiographic criteria was highest (n = 163, 12%) in the least stringent scenario (pain + function ≥80 at ≥2 visits); with few patients (n = 129, 2%) in the most stringent scenario (pain + function ≥80 at ≥4 visits). Using these prevalence data, a sample size of 352-2144 per group would be needed to demonstrate a 50% difference between groups. CONCLUSIONS: The prevalence of patients with sustained symptomatic OA of at least a moderate degree with X-ray progression is low. Even using lenient criteria to define VJR, large patient numbers would be required to detect differences between groups in DMOAD RCTs. Investigation of the optimal cutoff threshold and combination of symptoms and radiographic change should be pursued.


Asunto(s)
Antirreumáticos/uso terapéutico , Osteoartritis/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Índice de Severidad de la Enfermedad , Artroplastia de Reemplazo , Progresión de la Enfermedad , Determinación de Punto Final , Humanos , Osteoartritis/diagnóstico por imagen , Osteoartritis/fisiopatología , Dimensión del Dolor/métodos , Umbral del Dolor , Placebos , Radiografía , Resultado del Tratamiento
4.
Ann Rheum Dis ; 69(1): 155-62, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19103634

RESUMEN

OBJECTIVE: Cartilage morphology displays sensitivity to change in osteoarthritis (OA) with quantitative MRI (qMRI). However, (sub)regional cartilage thickness change at 3.0 Tesla (T) has not been directly compared with radiographic progression of joint space narrowing in OA participants and non-arthritic controls. METHODS: A total of 145 women were imaged at 7 clinical centres: 86 were non-obese and asymptomatic without radiographic OA and 55 were obese with symptomatic and radiographic OA (27 Kellgren-Lawrence grade (KLG)2 and 28 KLG3). Lyon-Schuss (LS) and fixed flexion (FF) radiographs were obtained at baseline, 12 and 24 months, and coronal spoiled gradient echo MRI sequences at 3.0 T at baseline, 6, 12 and 24 months. (Sub)regional, femorotibial cartilage thickness and minimum joint space width (mJSW) in the medial femorotibial compartment were measured and the standardised response means (SRMs) determined. RESULTS: At 6 months, qMRI demonstrated a -3.7% "annualised" change in cartilage thickness (SRM -0.33) in the central medial femorotibial compartment (cMFTC) of KLG3 subjects, but no change in KLG2 subjects. The SRM for mJSW in 12-month LS/FF radiographs of KLG3 participants was -0.68/-0.13 and at 24 months was -0.62/-0.20. The SRM for cMFTC changes measured with qMRI was -0.32 (12 months; -2.0%) and -0.48 (24 months; -2.2%), respectively. CONCLUSIONS: qMRI and LS radiography detected significant change in KLG3 participants at high risk of progression, but not in KLG2 participants, and only small changes in controls. At 12 and 24 months, LS displayed greater, and FF less, sensitivity to change in KLG3 participants than qMRI.


Asunto(s)
Cartílago Articular/patología , Osteoartritis de la Rodilla/patología , Adulto , Anciano , Cartílago Articular/diagnóstico por imagen , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Persona de Mediana Edad , Osteoartritis de la Rodilla/diagnóstico por imagen , Radiografía , Índice de Severidad de la Enfermedad
5.
Osteoarthritis Cartilage ; 18(8): 1008-11, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20493957

RESUMEN

OBJECTIVE: To estimate the extent to which varus malalignment, a source of abnormal intra-articular stresses in the medial tibiofemoral compartment and risk factor for progression of knee osteoarthritis (OA), may have diminished the structure-modifying benefit of doxycycline in knee OA. METHODS: Post hoc treatment group comparisons from a randomized, placebo-controlled trial of the effect of doxycycline (100mg, twice daily) on medial joint space narrowing (JSN) in subgroups of varus and non-varus OA knees. Subjects (N=379 with X-ray follow-up) were obese 45-64-year-old women with unilateral knee OA at baseline. JSN was measured manually in semiflexed anteroposterior (AP) radiographs acquired with standardized fluoroscopic positioning. The anatomic-axis angle (AAA) was measured in each baseline radiograph and transformed to an estimate of the mechanical-axis angle (MAA(est)) using a validated regression equation. Knees with MAA(est)<178 degrees were classified as varus. RESULTS: In our original comparison with placebo, doxycycline slowed the rate of medial JSN in OA knees by 38% at 16 months and by 33% at 30 months. Among non-varus OA knees, 16-month JSN in the doxycycline group was 44% slower than in the placebo group (0.09 vs 0.16 mm/year, P=0.080), and 39% slower at month 30 (0.10 vs 0.17 mm/year, P=0.026). JSN in varus knees (0.20-0.27 mm/year) was more rapid than in non-varus knees (P=0.083) and unaffected by doxycycline. CONCLUSION: Varus malalignment negated the slowing of structural progression of medial-compartment OA by doxycycline. To our knowledge, this is the first report documenting that static varus angulation can negate a pharmacologic structure-modifying effect.


Asunto(s)
Antiinfecciosos/uso terapéutico , Desviación Ósea/fisiopatología , Doxiciclina/uso terapéutico , Articulación de la Rodilla/efectos de los fármacos , Obesidad/complicaciones , Osteoartritis de la Rodilla/tratamiento farmacológico , Progresión de la Enfermedad , Femenino , Humanos , Persona de Mediana Edad , Osteoartritis de la Rodilla/fisiopatología , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
6.
Osteoarthritis Cartilage ; 18(11): 1436-40, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20813195

RESUMEN

OBJECTIVE: To determine, in serial fixed-flexion (FF) radiographs of subjects with knee osteoarthritis (KOA), the importance of, and basis for, the effect of alignment of the medial tibial plateau (MTP), as determined by the inter-margin distance (IMD), on joint space narrowing (JSN). METHODS: Baseline and 12-month X-rays of 590 knees with Kellgren and Lawrence grade (KLG) 2/3 OA from the public-release dataset of the Osteoarthritis Initiative (OAI) were assigned to subgroups based upon IMD at baseline (IMD(BL)) and the difference between IMD(BL) and IMD(12 mos). Relationships of JSN to IMD(BL) and to the difference between IMD(BL and) IMD(12 mos) were evaluated. RESULTS: In all 590 knees, mean JSN was 0.13 ± 0.51 mm (P<0.0001) and MTP alignment and replication of IMD(BL) in the 12-month film were, in general, poor. JSN was significantly (P=0.012) more rapid in Subgroup A (IMD≤1.70 mm at both time points) than in Subgroup B (both IMDs>1.70 mm): 0.15 ± 0.43; 0.08 ± 0.47. Within Subgroup B we identified a subset, Subgroup B1, in which, although alignment was poor at both time points, the large IMD(BL) was, by chance, highly reproduced by IMD(12 mos) (difference between the two IMDs=0.01 ± 0.27 mm, NS). JSN in Subgroup B1 was 0.06 ± 0.41 mm and did not differ from that in other knees of Subgroup B (P=0.87). The standardized response mean (SRM) in all 590 knees and Subgroups A, B and B1 was 0.25, 0.34, 0.17 and 0.06, respectively. Independent of IMD(BL), JSN correlated significantly with the difference between the IMDs in the two radiographs (r=0.17, P=0.0001). CONCLUSION: Skewed MTP alignment in serial films and poor replication of IMD(BL) in the follow-up exam affect JSN measurement. The magnitude of change in joint space width (JSW) related to the poor quality of alignment that is common with the FF view jeopardizes accurate evaluation of JSN.


Asunto(s)
Articulación de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/diagnóstico por imagen , Tibia/diagnóstico por imagen , Anciano , Progresión de la Enfermedad , Métodos Epidemiológicos , Femenino , Humanos , Articulación de la Rodilla/patología , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/patología , Radiografía
7.
Ann Rheum Dis ; 68(11): 1734-8, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19060003

RESUMEN

OBJECTIVE: Given that obesity is a risk factor for osteoarthritis (OA) of the knee, a study was undertaken to determine whether progressively higher body mass index (BMI) among obese women is associated with progressive increases in joint space narrowing (JSN). METHODS: Medial compartment JSN over 12 months in Lyon Schuss radiographs of 60 obese women (BMI 30.0-50.5 kg/m(2)) with radiographic and symptomatic OA was compared with that in 81 non-obese women (BMI <28 kg/m(2)) with normal radiographs and minimal or no symptoms of knee OA. RESULTS: Among the patients with OA, higher BMI tended to be associated with a higher Kellgren and Lawrence (KL) grade of OA severity. JSN in the non-obese controls was negligible, but in the 30 patients with KL grade 2 and KL grade 3 knees, mean (SD) JSN was 0.12 (0.31) mm and 0.32 (0.50) mm, respectively (p<0.005 and p<0.001). No association was seen between baseline BMI and 12-month JSN in patients with OA; indeed, the regression plot suggested a slight inverse relationship between the two. CONCLUSIONS: In obese patients with OA, progressively higher BMI values were not accompanied by a progressively increasing rate of JSN. Joint loading was not evaluated, but it is possible that marked obesity limited the functional capacity of some subjects with OA, protecting their knees from loading. For investigators considering eligibility criteria for a trial of a structure-modifying OA drug, these data suggest that recruitment of patients with a BMI much higher than 30 kg/m(2) will not enrich the sample of subjects who will have more rapid JSN than those with a BMI of only 30 kg/m(2).


Asunto(s)
Índice de Masa Corporal , Articulación de la Rodilla/patología , Obesidad/complicaciones , Osteoartritis de la Rodilla/patología , Adulto , Anciano , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Persona de Mediana Edad , Obesidad/fisiopatología , Osteoartritis de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/etiología , Radiografía , Índice de Severidad de la Enfermedad
8.
Osteoarthritis Cartilage ; 17(9): 1170-6, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19401243

RESUMEN

OBJECTIVE: To ascertain the contribution of articular cartilage morphometry and meniscal position on MRI to joint space width (JSW) measured in the Lyon schuss radiograph of the knee. DESIGN: 62 obese women with knee OA and 99 non-obese female controls (mean age 56.6 years) were imaged using 3T MRI and coronal water excitation spoiled gradient echo sequences. Segmentation of femorotibial cartilage morphology and regional morphometric analysis was performed using custom software. Meniscal position was measured quantitatively in sagittal and coronal planes. Minimum space width (mJSW) was measured in the Lyon Schuss knee radiograph; Kellgren and Lawrence grades (KLG) were assigned on standing anteroposterior knee films. The relative contribution of regional cartilage thickness and meniscal position to mJSW was assessed initially in univariate models and subsequently with multivariable modelling. RESULTS: 65% of the variation in mJSW was explained by regional cartilage thickness measures, different KLG and meniscal coverage. Of these measures the medial tibia cartilage thickness measures and central region of the central medial femur (ccMF) play a consistent role in variations in mJSW observed across all KLG. Further ccMF and the addition of percent meniscal coverage to this model explains the remaining differences in mean mJSW found between those subjects with definite joint space narrowing (KLG3) and those without OA. CONCLUSION: The variation in radiographic mJSW is best described by five regional cartilage thickness measures and percent meniscal coverage. The magnitude of each measures contribution differs according to radiographic severity with more variability explained by cartilage thickness of ccMF cartilage thickness and percent meniscal coverage with more severe disease.


Asunto(s)
Cartílago Articular/patología , Articulación de la Rodilla/patología , Meniscos Tibiales/patología , Osteoartritis de la Rodilla/patología , Adulto , Anciano , Índice de Masa Corporal , Cartílago Articular/diagnóstico por imagen , Femenino , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Meniscos Tibiales/diagnóstico por imagen , Persona de Mediana Edad , Obesidad , Osteoartritis de la Rodilla/diagnóstico por imagen , Radiografía , Índice de Severidad de la Enfermedad , Soporte de Peso
9.
Osteoarthritis Cartilage ; 17(7): 856-63, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19230857

RESUMEN

BACKGROUND: Joint space width (JSW) evaluated in millimeters on plain X-rays is the currently optimal recognized technique to evaluate osteoarthritis (OA) structural progression. Data obtained can be presented at the group level (e.g., mean+/-standard deviation of the changes). Such presentation makes difficult the interpretation of the clinical relevance of the reported results. Therefore, a presentation at the individual level (e.g., % progressors) seems more attractive but requires to determining a cut-off. Several methodologies have been proposed to define cut-offs in JSW: arbitrary chosen cut-off, cut-off based on the validity to predict a relevant end-point such as the requirement of total articular replacement or cut-off based on the measurement error such as smallest detectable difference (SDD). OBJECTIVES: The objective of this OARSI-OMERACT initiative was to define a cut-off evaluated in millimeters on plain X-rays above which a change in JSW could be considered as relevant in patients with hip and knee OA. METHODS: The first step consisted in a systematic literature research performed using Medline database up to July 2007 to obtain all manuscripts published between 1990 and 2007 reporting a cut-off value in JSW evaluated in millimeters at either the knee or hip level. The second step consisted in a consensus based on the best knowledge of the 11 experts with the support of the available evidence. RESULTS: Among the 506 articles selected by the search, 47 articles reported cut-off of JSW in millimeters. There was a broad heterogeneity in cut-off values, whatever the methodologies or the OA localization considered (e.g., from 0.12 to 0.84 mm and from 0.22 to 0.78 mm for Knee (seven studies) and hip (seven studies), respectively when considering the data obtained based on the reliability). Based on the data extracted in the literature, the expert committee proposed a definition of relevant change in JSW based on plain X-rays, on an absolute change of JSW in millimeters and on the measurement error e.g., calculation of the SDD using the Bland and Altman technique. The results of the analysis of JSW should be expressed in terms of a dichotomous variable (e.g., progressors yes/no): a patient with a change in JSW during the study over such SDD will fulfill the definition of "progressor". Moreover, the pilot study aimed at evaluating the measurement error should be designed to reflect the different characteristics of the primary study in which the analysis of the radiological findings will be based on (patient's characteristics, centers characteristics, readers). CONCLUSION: This initiative based on both an Evidence Based Medicine (Systematic Literature Research) and Expert Opinion approach resulted in a proposal of definition of relevant radiological progression in OA to be used as end-point in clinical trials and also recommendations on the conduct of the reliability study allowing such definition.


Asunto(s)
Articulación de la Cadera/patología , Articulación de la Rodilla/patología , Osteoartritis de la Cadera/patología , Osteoartritis de la Rodilla/patología , Ensayos Clínicos como Asunto , Consenso , Progresión de la Enfermedad , Estudios de Factibilidad , Articulación de la Cadera/diagnóstico por imagen , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Osteoartritis de la Cadera/diagnóstico por imagen , Osteoartritis de la Rodilla/diagnóstico por imagen , Radiografía , Valores de Referencia
10.
Osteoarthritis Cartilage ; 17(9): 1177-85, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19341831

RESUMEN

OBJECTIVE: To identify subregional differences in femorotibial cartilage morphology between healthy controls and women with different grades of radiographic knee osteoarthritis (OA). DESIGN: 158 women aged > or =40 years were studied. Weight-bearing extended anterior-posterior (AP) and Lyon schuss radiographs were obtained and the Kellgren Lawrence grade (KLG) determined. 97 women had a body mass index (BMI)< or =28, no symptoms, and were AP KLG0. 61 women had a BMI> or =30, symptoms in the target knee, and mild (KLG2=31) to moderate (KLG3=30) medial femorotibial radiographic OA in the AP views. Coronal spoiled gradient echo water excitation sequences were acquired at 3.0 Tesla. Total plate and regional measures of cartilage morphology of the weight-bearing femorotibial joint were quantified. RESULTS: KLG2 participants displayed, on average, thicker cartilage than healthy controls in the medial femorotibial compartment (particularly anterior subregion of the medial tibia (MT) and peripheral [external, internal] subregions of the medial femur), and in the lateral femur. KLG3 participants displayed significantly thinner cartilage than KLG0 participants in the medial weight-bearing femur (central subregion), in the external subregion of the MT, and in the internal subregion of the lateral tibia. These differences were generally unaffected when possible effects of demographic covariates were considered. CONCLUSIONS: The results indicate that in femorotibial OA regional cartilage thickening and thinning may occur, dependent on the (radiographic) disease status of the joint. These changes appear to display a heterogeneous spatial pattern, where certain subregions are more strongly affected than others.


Asunto(s)
Cartílago Articular/patología , Articulación de la Rodilla/patología , Osteoartritis de la Rodilla/patología , Adulto , Anciano , Cartílago Articular/diagnóstico por imagen , Estudios Transversales , Femenino , Fémur/diagnóstico por imagen , Fémur/patología , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Estudios Longitudinales , Imagen por Resonancia Magnética/métodos , Persona de Mediana Edad , Osteoartritis de la Rodilla/diagnóstico por imagen , Radiografía , Estadística como Asunto , Tibia/diagnóstico por imagen , Tibia/patología
11.
Ann Rheum Dis ; 67(11): 1562-6, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18258709

RESUMEN

OBJECTIVE: The Lyon Schuss (LS) and fixed flexion (FF) views of the knee are superior to a conventional standing anteroposterior view in evaluating joint space narrowing (JSN) in osteoarthritis (OA). Both position the knee identically but only the LS aligns the medial tibial plateau (MTP) with the x-ray beam fluoroscopically. The present study provides the first head-to-head comparison of the LS and FF views. METHODS: At baseline and 12 months, 62 OA and 99 control knees were imaged twice on the same day with LS and FF views. Minimum joint space width (mJSW) was measured by computer and MTP alignment was assessed from the distance between anterior and posterior margins of the MTP (intermargin distance, IMD). Reproducibility of measurements of mJSW and sensitivity to change were evaluated. RESULTS: In normal knees, JSW did not vary over 12 months with either view. In OA knees, 12-month mJSN was 0.22 (0.43) mm with the LS view and -0.01 (0.46) mm with the FF view (p = 0.0002 and p = 0.92, respectively). Mean IMD was only half as large in LS as in FF views (0.9 (0.5) mm vs 1.9 (1.2) mm, p<0.0001). CONCLUSIONS: LS and FF radiographs offer similar reproducibility in JSW measurement. However, presumably due to its superiority in aligning the MTP, the LS view is much more sensitive to JSN in OA knees.


Asunto(s)
Articulación de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/diagnóstico por imagen , Adulto , Anciano , Artrografía/métodos , Progresión de la Enfermedad , Métodos Epidemiológicos , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Articulación de la Rodilla/anatomía & histología , Articulación de la Rodilla/patología , Persona de Mediana Edad , Variaciones Dependientes del Observador , Osteoartritis de la Rodilla/patología , Postura , Índice de Severidad de la Enfermedad
12.
Ann Rheum Dis ; 67(12): 1683-8, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18283054

RESUMEN

OBJECTIVE: Quantitative MRI (qMRI) of cartilage morphology is a promising tool for disease-modifying osteoarthritis drug (DMOAD) development. Recent studies at single sites have indicated that measurements at 3.0 Tesla (T) are more reproducible (precise) than those at 1.5 T. Precision errors and stability in multicentre studies with imaging equipment from various vendors have, however, not yet been evaluated. METHODS: A total of 158 female participants (97 Kellgren and Lawrence grade (KLG) 0, 31 KLG 2 and 30 KLG 3) were imaged at 7 clinical centres using Siemens Magnetom Trio and GE Signa Excite magnets. Double oblique coronal acquisitions were obtained at baseline and at 3 months, using water excitation spoiled gradient echo sequences (1.0x0.31x0.31 mm3 resolution). Segmentation of femorotibial cartilage morphology was performed using proprietary software (Chondrometrics GmbH, Ainring, Germany). RESULTS: The precision error (root mean square coefficient of variation (RMS CV)%) for cartilage thickness/volume measurements ranged from 2.1%/2.4% (medial tibia) to 2.9%/3.3% (lateral weight-bearing femoral condyle) across all participants. No significant differences in precision errors were observed between KLGs, imaging sites, or scanner manufacturers/types. Mean differences between baseline and 3 months ranged from <0.1% (non-significant) in the medial to 0.94% (p<0.01) in the lateral femorotibial compartment, and were 0.33% (p<0.02) for the total femorotibial subchondral bone area. CONCLUSIONS: qMRI performed at 3.0 T provides highly reproducible measurements of cartilage morphology in multicentre clinical trials with equipment from different vendors. The technology thus appears sufficiently robust to be recommended for large-scale multicentre trials.


Asunto(s)
Cartílago Articular/patología , Articulación de la Rodilla/patología , Imagen por Resonancia Magnética/normas , Osteoartritis de la Rodilla/patología , Anciano , Cartílago Articular/anatomía & histología , Femenino , Estudios de Seguimiento , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Articulación de la Rodilla/anatomía & histología , Imagen por Resonancia Magnética/instrumentación , Imagen por Resonancia Magnética/métodos , Persona de Mediana Edad , Osteoartritis de la Rodilla/tratamiento farmacológico , Reproducibilidad de los Resultados , Evaluación de la Tecnología Biomédica
13.
Osteoarthritis Cartilage ; 16(12): 1555-9, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18515156

RESUMEN

OBJECTIVE: This study evaluated the longitudinal performance of a modified Lyon schuss (LS) knee examination in the detection of radiographic joint space narrowing (JSN) in knees with osteoarthritis (OA). The modified LS exam entails two to four iterative acquisitions with empirically adjusted angulation of the X-ray beam to achieve superimposition of the anterior and posterior margins of the medial tibial plateau (MTP), a marker of parallel radioanatomic alignment that the original LS exam achieves with fluoroscopically guided beam angulation. METHODS: Seventy-four obese women with symptomatic knee OA underwent LS and fixed-flexion (FF, caudal 10 degrees beam angulation) X-ray exams at baseline and 1 year later. For 47 subjects, beam angulation for both LS exams was guided by fluoroscopy. For 27 subjects, the modified LS exam was performed at one or both times. Modified and original LS procedures were evaluated relative to concurrent FF radiographs with respect to the inter-margin distance (IMD) at the MTP midpoint (quality and reproducibility of alignment) and sensitivity to JSN. RESULTS: Compared to FF radiographs, modified LS radiographs afforded a smaller mean IMD at baseline (0.89 vs 2.06 mm, P=0.002), more reproducible IMD (mean change=0.49 vs 0.91 mm, P=0.007) and more rapid JSN (mean=0.25 vs 0.02 mm/yr, P=0.005). These differences paralleled those observed between original LS and FF procedures with respect to baseline alignment (0.96 vs 1.94 mm, P<0.001), reproducibility of alignment (0.49 vs 1.00 mm, P<0.001) and sensitivity to JSN (0.16 vs -0.01 mm/yr, P=0.007). CONCLUSION: In clinical centers where the absence of fluoroscopy equipment precludes use of the original LS protocol, a modified procedure employing iterative, empirical adjustment of the beam angle to achieve parallel radioanatomic alignment with the MTP affords a degree of superiority over the FF protocol with respect to quality and reproducibility of positioning and sensitivity to JSN in OA knees similar to that of the original.


Asunto(s)
Diagnóstico por Imagen/normas , Articulación de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/diagnóstico por imagen , Tibia/diagnóstico por imagen , Progresión de la Enfermedad , Femenino , Humanos , Articulación de la Rodilla/fisiología , Persona de Mediana Edad , Obesidad/complicaciones , Osteoartritis de la Rodilla/fisiopatología , Postura , Radiografía , Índice de Severidad de la Enfermedad , Tibia/fisiología
14.
Sci Data ; 3: 160115, 2016 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-27996971

RESUMEN

Posidonia oceanica is an endemic seagrass in the Mediterranean Sea, where it provides important ecosystem services and sustains a rich and diverse ecosystem. P. oceanica meadows extend from the surface to 40 meters depth. With the aim of boosting research in this iconic species, we generated a comprehensive RNA-Seq data set for P. oceanica by sequencing specimens collected at two depths and two times during the day. With this approach we attempted to capture the transcriptional diversity associated with change in light and other depth-related environmental factors. Using this extensive data set we generated gene predictions and identified an extensive catalogue of potential Simple Sequence Repeats (SSR) markers. The data generated here will open new avenues for the analysis of population genetic features and functional variation in P. oceanica. In total, 79,235 contigs were obtained by the assembly of 70,453,120 paired end reads. 43,711 contigs were successfully annotated. A total of 17,436 SSR were identified within 13,912 contigs.


Asunto(s)
Alismatales/genética , Transcriptoma , Ecosistema , Genética de Población , Mar Mediterráneo , Repeticiones de Microsatélite
15.
Diabetes Care ; 6(4): 347-50, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6617411

RESUMEN

The purpose of this study was to identify the types of statements used by medical and nursing clinicians in encounters with diabetic outpatients that are associated with accurate comprehension of their therapeutic regimen. Encounters between 19 clinicians and 29 patients followed in an urban diabetes clinic were examined. Statements made by clinicians were classified by trained observers according to an 11-category observation scheme. Immediately after the encounters, each patient was interviewed and asked to recall his or her regimen as just discussed. Recall was verified by review of a videotape of the encounter. By use of multiple discriminant analysis, a combination of three types of statements by clinicians was found to predict high (better than 80%) comprehension by patients: demonstrating respect, sharing current clinical data, and acknowledging patient statements (inversely). Insofar as patient comprehension of the diabetic regimen is a prerequisite for compliance with that regimen, this study suggests that the chances for therapeutic success are increased when the interaction of clinician and patient takes a certain tone. Most importantly, the clinician should be informative. Current laboratory and physical findings should be shared with the patient in order to make more obvious the successes and failures of recent attempts at compliance. As suggested in previous research, this information should have its strongest effect when conveyed in a nonthreatening manner.


Asunto(s)
Comunicación/métodos , Diabetes Mellitus/terapia , Relaciones Médico-Paciente , Relaciones Profesional-Paciente , Femenino , Humanos , Masculino , Recuerdo Mental , Persona de Mediana Edad , Participación del Paciente
16.
Diabetes Care ; 9(1): 1-10, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3948638

RESUMEN

The Diabetes Education Study (DIABEDS) was a randomized, controlled trial of the effects of patient and physician education. This article describes a systematic education program for diabetes patients and its effects on patient knowledge, skills, self-care behaviors, and relevant physiologic outcomes. The original sample consisted of 532 diabetes patients from the general medicine clinic at an urban medical center. Patients were predominantly elderly, black women with non-insulin-dependent diabetes mellitus of long duration. Patients randomly assigned to experimental groups (N = 263) were offered up to seven modules of patient education. Each content area module contained didactic instruction (lecture, discussion, audio-visual presentation), skill exercises (demonstration, practice, feedback), and behavioral modification techniques (goal setting, contracting, regular follow-up). Two hundred seventy-five patients remained in the study throughout baseline, intervention, and postintervention periods (August 1978 to July 1982). Despite the requirement that patients demonstrate mastery of educational objectives for each module, postintervention assessment 11-14 mo after instruction showed only rare differences between experimental and control patients in diabetes knowledge. However, statistically significant group differences in self-care skills and compliance behaviors were relatively more numerous. Experimental group patients experienced significantly greater reductions in fasting blood glucose (-27.5 mg/dl versus -2.8 mg/dl, P less than 0.05) and glycosylated hemoglobin (-0.43% versus + 0.35%, P less than 0.05) as compared with control subjects. Patient education also had similar effects on body weight, blood pressure, and serum creatinine. Continued follow-up is planned for DIABEDS patients to determine the longevity of effects and subsequent impact on emergency room visits and hospitalization.


Asunto(s)
Diabetes Mellitus/terapia , Educación del Paciente como Asunto , Glucemia/metabolismo , Peso Corporal , Diabetes Mellitus/sangre , Hemoglobina Glucada/análisis , Homeostasis , Humanos , Cooperación del Paciente
17.
Free Radic Biol Med ; 14(6): 589-99, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7686874

RESUMEN

Human neutrophils activated by PMA were found to induce the formation of a nitroxide radical from DFO. The presence of SOD was necessary to permit the formation of the DFO radical. The inactive phorbol ester did not induce DFO radical, and DL-sphinganine suppressed the radical produced by the active phorbol ester. Other cell stimuli (Zymocel and the chemotactic peptide) also induced the formation of the DFO radical, although radical concentration was very much lower than with PMA. Participation of NO, OH or 1O2 was ruled out by the inability of NG-methyl-L-arginine, NG-nitro-L-arginine, DMSO, mannitol, histidine, and methionine to inhibit the formation of DFO radical produced by PMA-activated cells. Furthermore, PMA-activated cells did not produce detectable levels of NO2-, a stable oxidation product of NO, and D2O, which enhances the lifetime of singlet oxygen, did not modify the intensity or the lifetime of DFO radical. The involvement of cell MPO was suggested by the inhibition of the DFO radical observed after treatment with catalase or with antihuman MPO antibodies. Also, HOCl was found to induce the DFO radical in cell-free reactions, but our data indicate that the reaction leading to DFO radical formation by neutrophils involves the reduction of MPO compound II back to the active enzyme (ferric-MPO). Anti-inflammatory drugs strongly increased the DFO radical produced by activated neutrophils. On the contrary, none of these drugs was able to increase the DFO radical produced by HOCl. Histidine and methionine that inhibited the DFO radical intensity in cell-free reactions, were shown to act directly on HOCl. Experiments with MPO-H2O2 in SOD- and Cl(-)-free conditions showed the formation of DFO radical and confirmed the hypothesis of the involvement of compound II. The conversion of compound II to ferric MPO by DFO optimized the enzymatic activity of neutrophils, and in the presence of monochlorodimedon (compound II promoting agent) we measured an increased HOCl production. When DFO was modified by conjugation with hydroxyethyl starch, it lost the ability to produce the radical either by neutrophils or by MPO-H2O2 and did not increase HOCl production. The inability of these DFO derivatives to produce potentially toxic species might explain their reported lower toxicity in vivo.


Asunto(s)
Deferoxamina/metabolismo , Neutrófilos/metabolismo , Deferoxamina/farmacología , Depuradores de Radicales Libres , Radicales Libres/metabolismo , Humanos , Derivados de Hidroxietil Almidón/metabolismo , Derivados de Hidroxietil Almidón/farmacología , Ácido Hipocloroso/metabolismo , Técnicas In Vitro , Neutrófilos/efectos de los fármacos , Óxidos de Nitrógeno/metabolismo , Oxidación-Reducción , Peroxidasa/antagonistas & inhibidores , Peroxidasa/metabolismo , Superóxido Dismutasa/metabolismo , Acetato de Tetradecanoilforbol/farmacología
18.
Rheum Dis Clin North Am ; 25(2): 467-80, ix, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10356429

RESUMEN

The identification of pharmacologic agents that inhibit matrix metalloproteinase activity and may serve as effective disease-modifying osteoarthritis drugs (DMOADs) in humans has led to interest in the ability of plain radiographic methods to detect early cartilage damage and assess progressive cartilage changes of knee osteoarthritis (OA). Conventional knee radiography lacks sufficient standardization of key elements of the radioanatomic positioning of the knee to avoid significant, probably insurmountable, error variation in the measurement of tibiofemoral joint space width (JSW), the surrogate for the thickness of articular cartilage in radiographic images. Recently, several protocols for the use of fluoroscopy to standardize the radioanatomic position of the knee in a plain radiograph have been shown to afford notably more precise measurement of medial tibiofemoral JSW than can be derived from unstandardized, conventional techniques. A field test of one of these protocols suggests that DMOAD trials with respect to sample size or duration of treatment necessary to detect true OA progression and demonstrate a drug effect may be more feasible.


Asunto(s)
Artrografía/normas , Osteoartritis de la Rodilla/diagnóstico por imagen , Antirreumáticos/uso terapéutico , Fluoroscopía/métodos , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/patología , Estudios Multicéntricos como Asunto , Osteoartritis de la Rodilla/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
19.
Arthritis Care Res ; 6(2): 59-63, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8399427

RESUMEN

This study examined whether the clinical environment could be used to increase internal medicine house officers' adoption of care recommendations taught in a didactic conference. Subjects were 11 internal medicine house officers who served 6-week rheumatology elective rotations. At the start of each of four rotation periods, house officers attended a 1-hour conference in which periarticular rheumatic disorders associated with knee pain (anserine bursitis, pseudothrombophlebitis) and shoulder pain (bicipital tendinitis) were discussed. All house officers also practiced physical examination techniques on anatomic models simulating the disorders. During alternate rotation periods, reminder sheets were appended to the records of arthritis patients with histories of chronic knee or shoulder pain. The frequency with which house officers followed conference recommendations was documented by direct observation (6 house officers in 17 encounters with reminders, 5 house officers in 30 encounters without reminders). Specific questioning about a recent history of knee or shoulder pain and the performance of four of five recommended physical examination maneuvers were increased significantly by reminder sheets in patients' charts (P < 0.05 for all). Although rheumatology faculty often have limited options available to increase the number of house officer trainees or to intensify clinical activity, qualitative improvements within existing logistic parameters are feasible by assuring that the clinical environment (e.g., patient records) contains salient cues that will prompt desired actions.


Asunto(s)
Competencia Clínica , Educación de Postgrado en Medicina/métodos , Cuerpo Médico de Hospitales/educación , Derivación y Consulta , Reumatología/educación , Humanos , Medicina Interna/educación
20.
Arthritis Care Res ; 10(5): 289-99, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9362595

RESUMEN

OBJECTIVE: To evaluate the nature, risks, and benefits of osteoarthritis (OA) management by primary care physicians and rheumatologists. METHODS: Subjects were 419 patients followed for symptoms of knee OA by either a specialist in family medicine (FM) or general internal medicine (GIM) or by a rheumatologist (RH). Management practices were characterized by in-home documentation by a visiting nurse of drugs taken to relieve OA pain or to prevent gastrointestinal side effects of nonsteroidal anti-inflammatory drugs (NSAIDs) and by patient report (self-administered survey) of nonpharmacologic treatments. Changes in outcomes (knee pain and physical function) over 6 months were measured with the Western Ontario and McMaster Universities Osteoarthritis Index. RESULTS: Patients of RHs were 2-3 years older (P = 0.035) and tended to exhibit greater radiographic severity of OA (P = 0.064) and poorer physical function (P = 0.076) at baseline than the other 2 groups. In all 3 groups, knee pain and physical function improved slightly over 6 months; however, between-group differences were not significant. Compared to drug management of knee pain by FMs or RHs, that by the GIMs was distinguished by greater utilization of acetaminophen and nonacetylated salicylates (P = 0.008), lower prescribed doses of NSAIDs (P = 0.007), and, therefore, lower risk of iatrogenic gastroenteropathy (P < 0.001). In contrast, patients of RHs were more likely than those of FMs and GIMs to report that they had been instructed in use of isometric quadriceps and range-of-motion exercises (P < or = 0.001), application of heat (P = 0.051) and cold (P < 0.001) packs, and in the principles of joint protection (P = 0.016). Neither physician specialty nor specific management practices accounted for variations in patient outcomes. CONCLUSION: This observational study identified specialty-related variability in key aspects of the management of knee OA in the community (i.e., frequency and dosing of NSAIDs, use of nonpharmacologic modalities) that bear strong implications for long-term safety and cost. However, changes in knee pain and function over 6 months were unrelated to variations in management practices.


Asunto(s)
Medicina Familiar y Comunitaria , Medicina Interna , Osteoartritis/terapia , Reumatología , Actividades Cotidianas , Anciano , Antiinflamatorios no Esteroideos/efectos adversos , Antiinflamatorios no Esteroideos/uso terapéutico , Artralgia/tratamiento farmacológico , Estudios de Cohortes , Terapia por Ejercicio , Femenino , Humanos , Articulación de la Rodilla , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento
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