RESUMEN
A fourth of the global seabed sediment volume is buried at depths where temperatures exceed 80 °C, a previously proposed thermal barrier for life in the subsurface. Here, we demonstrate, utilizing an extensive suite of radiotracer experiments, the prevalence of active methanogenic and sulfate-reducing populations in deeply buried marine sediment from the Nankai Trough subduction zone, heated to extreme temperature (up to ~120 °C). The small microbial community subsisted with high potential cell-specific rates of energy metabolism, which approach the rates of active surface sediments and laboratory cultures. Our discovery is in stark contrast to the extremely low metabolic rates otherwise observed in the deep subseafloor. As cells appear to invest most of their energy to repair thermal cell damage in the hot sediment, they are forced to balance delicately between subsistence near the upper temperature limit for life and a rich supply of substrates and energy from thermally driven reactions of the sedimentary organic matter.
Asunto(s)
Bacterias/metabolismo , Radioisótopos de Carbono/metabolismo , Sedimentos Geológicos/microbiología , Calor , Microbiota , Sulfatos/metabolismo , Radioisótopos de Azufre/metabolismo , Bacterias/crecimiento & desarrollo , Sedimentos Geológicos/análisis , Sedimentos Geológicos/química , Trazadores RadiactivosRESUMEN
OBJECTIVE: Graft hypertrophy is a major complication seen in autologous chondrocyte implantation (ACI) with a periosteal flap. We present the first magnetic resonance imaging (MRI) classification for periosteal hypertrophy including a grading of clinical symptoms and the surgical consequences. METHODS: One hundred and two patients with isolated chondral defects underwent an ACI covered with periosteum and were evaluated preoperatively, 6, 18 and 36 months after surgery. Exclusion criteria were meniscal pathologies, axial malpositioning and ligament instabilities. Baseline clinical scores were compared with follow-up data by paired Wilcoxon-tests for the modified Cincinnati knee, the ICRS (International Cartilage Repair Society) and a new MRI score including the parameters defect filling, subchondral edema, effusion, cartilage signal and graft hypertrophy. Hypertrophic changes were graded from 1 (minimal) to 4 (severe). RESULTS: All scores showed significant improvement (P<0.001) over the entire study period. Patients with femoral lesions had significantly better results than patients with patella lesions after 18 and 36 months postoperative (P<0.03). Periosteal hypertrophy occurred in 28% of all patients. Fifty percent of all patella implants developed hypertrophic changes. No patient with grade 1, and all patients with grade 4 hypertrophy had to undergo revision surgery. The Pearson correlation between graft hypertrophy and ICRS score was 0.78 after 6 months, and 0.69 after 36 months (P<0.01). Inclusion of graft hypertrophy in the MRI score improves the correlation to clinical scores from 0.6 to 0.69. CONCLUSIONS: Grading graft hypertrophy helps to identify patients needing an early shaving of the graft. Its integration into an MRI score improves correlation with clinical scores. Re-operation depends on the grade of hypertrophy and clinical symptoms.
Asunto(s)
Enfermedades de los Cartílagos/cirugía , Condrocitos/trasplante , Articulación de la Rodilla/cirugía , Periostio/patología , Adolescente , Adulto , Enfermedades de los Cartílagos/clasificación , Enfermedades de los Cartílagos/patología , Trasplante de Células/métodos , Femenino , Supervivencia de Injerto , Humanos , Hipertrofia , Articulación de la Rodilla/patología , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Selección de Paciente , Estudios Prospectivos , Reoperación , Trasplante AutólogoRESUMEN
OBJECTIVE: To determine if the clinical results after microfracture of full-thickness cartilage lesions deteriorate over a period of 36 months. METHODS: Between 1999 and 2002 85 patients (mean age 39.5 years) with full-thickness cartilage lesions underwent the microfracture procedure and were evaluated preoperatively and 6, 18 and 36 months after surgery. Exclusion criteria were meniscal pathologies, axial malpositioning and ligament instabilities. Baseline clinical scores were compared with follow-up data by paired Wilcoxon-tests for the modified Cincinnati knee and the International Cartilage Repair Society (ICRS)-score. The effects of the lesion localization and Magnetic resonance imaging (MRI) parameters were evaluated using the Pearson correlation and independent samples tests. RESULTS: Both scores revealed significant improvement 18 months after microfracture (P<0.0001). Within the second 18 months after surgery there was a significant deterioration in the ICRS-score (P<0.0001). The best results could be observed in chondral lesions of the femoral condyles. Defects in other areas of the knee deteriorated between 18 and 36 months after microfracture. MRI 36 months after surgery revealed best defect filling in lesions on the femoral condyles with significant difference in the other areas (P<0.02). The Pearson coefficient of correlation between defect filling and ICRS-score was 0.84 and significant at the 0.01 level. CONCLUSIONS: Microfracture is a minimal invasive method with good short-term results in the treatment of small cartilage defects. A deterioration of the results starts 18 months after surgery and is most evident in the ICRS-score. The best prognostic factors have young patients with defects on the femoral condyles.
Asunto(s)
Cartílago Articular/cirugía , Fracturas del Cartílago/cirugía , Articulación de la Rodilla/cirugía , Osteoartritis de la Rodilla/cirugía , Adulto , Artroscopía/métodos , Cartílago Articular/patología , Femenino , Fracturas del Cartílago/patología , Humanos , Articulación de la Rodilla/patología , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Osteoartritis de la Rodilla/patología , Complicaciones Posoperatorias , Estudios Prospectivos , Resultado del TratamientoRESUMEN
OBJECTIVE: Needle sticks are a continuous concern in the health care environment because of the prevalence of bloodborne pathogens in today's society. Radioactive contamination is another concern with needle sticks during nuclear medicine and nuclear pharmacy procedures. In our institution, substantial efforts have been made to prevent needle sticks, but they still occur occasionally. The purpose of this project was to analyze different practices and products to determine the best protocol in an effort to avoid further needle sticks. METHODS: The nuclear medicine technologists were surveyed to determine how many needle sticks have occurred and the situation behind each occurrence. Using our initial survey, the circumstances involved in each incident were reviewed, suggestions considered, and various means of protection analyzed. Five options were presented in a second survey. RESULTS: The results of the second survey showed that technologists favored the newly designed needle-capping blocks for preventing needle sticks in their daily routine procedures. CONCLUSION: The newly designed needle-capping block is best suited for both nuclear medicine and nuclear pharmacy laboratories. We will continue to monitor the effectiveness of this new approach in preventing needle sticks.
Asunto(s)
Accidentes de Trabajo/prevención & control , Técnicos Medios en Salud , Lesiones por Pinchazo de Aguja/prevención & control , Radiofármacos/administración & dosificación , Recolección de Datos , Diseño de Equipo , Humanos , Medicina NuclearRESUMEN
OBJECTIVE: Previous studies of pain behavior in patients with chronic pain have shown that depressed patients exhibit more pain behavior than nondepressed patients. This study sought to extend these findings and to examine the possible causes of the observed differences. DESIGN: Patients completed the short form of the Beck Depression Inventory, and their pain behavior was simultaneously rated by themselves and trained observers. PATIENTS: Subjects were 37 inpatients in a chronic pain program. RESULTS: Both depressed and nondepressed subjects rated themselves as exhibiting more pain behavior than did nurse ratings. While nurses rated pain behaviors as similar among the depressed and the nondepressed groups, patient ratings indicated significantly more pain behavior among depressed than nondepressed patients. CONCLUSIONS: These results suggest that cognitive factors may influence self-ratings of pain behavior by depressed subjects.
Asunto(s)
Conducta , Depresión/psicología , Dolor/psicología , Adulto , Enfermedad Crónica , Humanos , Persona de Mediana Edad , Enfermeras y Enfermeros , Variaciones Dependientes del Observador , Manejo del Dolor , Dimensión del Dolor , Autoevaluación (Psicología) , Índice de Severidad de la EnfermedadRESUMEN
This study examined the impact of two dimensions of pain distribution (extent, site) on patient reports of pain intensity and duration among 105 patients with chronic pain. Pain extent was found to be associated strongly with reports of pain intensity and pain duration. When variance associated with pain extent was controlled, however, pain site was not associated with reported pain intensity, a finding inconsistent with previous research. Possible explanations for this inconsistency are discussed, and directions for further research are proposed.
Asunto(s)
Dolor/fisiopatología , Enfermedad Crónica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndromes del Dolor Miofascial/fisiopatología , Dolor/diagnóstico , Dolor/psicología , Dimensión del Dolor/métodos , Factores de TiempoRESUMEN
This study examined the initial symptoms of patients with chronic pain who were (n = 70) or were not (n = 52) involved in some aspect of the compensation system--worker's compensation, litigation, or Social Security Disability Insurance. Analyses indicated that compensation patients were discriminable from noncompensation patients (p less than 0.0001). Compensation patients were younger and less likely to be female; they also tended to report fewer surgeries, shorter pain durations, and more vocational and sexual disability. Finally, they perceived their medical conditions to be more severe than had been diagnosed by physicians. The groups did not seem to differ in severity of pain or psychologic distress. These data are consistent with studies indicating that compensation patients are not "symptom magnifiers," although the data do indicate that the life disruptions reported by these patients may be greater than those reported by patients not involved in compensation systems.
Asunto(s)
Evaluación de la Discapacidad , Dolor/psicología , Adulto , Enfermedad Crónica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Indemnización para TrabajadoresRESUMEN
The Pain Disability Index (PDI) is a brief instrument that was developed to assess pain-related disability, providing information that complements assessment of physical impairment. This paper presents the results of two studies concerning the psychometric properties and the validity of the PDI. In study I, PDI scores of 108 patients appeared internally consistent (alpha = .86), although a factor analysis revealed two factors. The first factor (59.3% of variance) seemed to include more discretionary, less obligatory activities. The second factor (14.3% of variance) included activities more basic to daily living and survival. Study II found that the PDI scores of 37 former inpatients were significantly higher than 36 former outpatients who responded to a follow-up questionnaire. These findings support the validity of the PDI. Several methodologic issues are discussed, and suggestions are made for future uses of the instrument.