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1.
Int J Emerg Med ; 16(1): 67, 2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37803269

RESUMEN

BACKGROUND: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a potentially life-saving procedure for bleeding trauma patients. Being a rare and complex procedure performed in extreme situations, repetitive training of REBOA teams is critical. Evidence-based guidelines on how to train REBOA are missing, although simulation-based training has been shown to be effective but can be costly and complex. We aimed to determine the feasibility and acceptance of REBOA training using a fully immersive virtual reality (VR) REBOA simulation, as well as assess the confidence in conducting the REBOA procedure before and after the training. METHODS: Prospective feasibility pilot study of prehospital emergency physicians and paramedics in Bern, Switzerland, from November 2020 until March 2021. Baseline characteristics of trainees, prior training and experience in REBOA and with VR, variables of media use (usability: system usability scale, immersion/presence: Slater-Usoh-Steed, workload: NASA-TLX, user satisfaction: USEQ) as well as confidence prior and after VR training were accessed. RESULTS: REBOA training in VR was found to be feasible without relevant VR-specific side-effects. Usability (SUS median 77.5, IQR 71.3-85) and sense of presence and immersion (Slater-Usoh-Steed median 4.8, IQR 3.8-5.5) were good, the workload without under-nor overstraining (NASA-TLX median 39, IQR 32.8-50.2) and user satisfaction high (USEQ median 26, IQR 23-29). Confidence of trainees in conducting REBOA increased significantly after training (p < 0.001). CONCLUSIONS: Procedural training of the REBOA procedure in immersive virtual reality is possible with a good acceptance and high usability. REBOA VR training can be an important part of a training curriculum, with the virtual reality-specific advantages of a time- and instructor-independent learning.

2.
J ECT ; 38(1): 39-44, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-34739421

RESUMEN

OBJECTIVES: Dementia with Lewy bodies (DLB) is a debilitating disorder associated with a number of distressing neuropsychiatric symptoms. There is currently limited guidance regarding the most effective strategies of managing these symptoms, and both pharmacologic and nonpharmacologic strategies are often used. Electroconvulsive therapy (ECT) has been reported as a potential nonpharmacologic method to alleviate some of these debilitating neuropsychiatric symptoms. However, there remains a paucity of evidence in current literature. This report aims to add to existing literature regarding ECT in DLB by highlighting successful treatment in seven cases. METHODS: Our study is a retrospective case series of 7 patients with DLB who received treatment with ultrabrief (UB) right unilateral (RUL) ECT for the treatment of agitation and depressive symptoms. Participants included patients with a diagnosis of DLB who were admitted to Emory University Hospital at Wesley Woods from 2011 to 2020 presenting with agitation and/or depressive symptoms after failing pharmacologic intervention. Patients underwent UB RUL ECT administered by a board-certified psychiatrist. After treatment, Pittsburg Agitation Scale and Clinical Global Impression-Improvement scales were recorded as measures of agitation and clinical improvement, respectively. RESULTS: All 7 patients responded to UB RUL ECT with marked improvement in their presenting symptoms of agitation and/or depression without significant adverse effects from treatment. CONCLUSIONS: Ultrabrief RUL ECT seems to be a safe and effective treatment of the agitative and depressive features of DLB.


Asunto(s)
Terapia Electroconvulsiva , Enfermedad por Cuerpos de Lewy , Terapia Electroconvulsiva/métodos , Humanos , Enfermedad por Cuerpos de Lewy/terapia , Estudios Retrospectivos , Resultado del Tratamiento
3.
J Affect Disord ; 290: 197-201, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-34004401

RESUMEN

BACKGROUND: Bipolar Affective Disorder (BPAD) accounts for 10-25% of all mood disorders in the geriatric population and 5% of all inpatient admissions to geropsychiatric units. Electroconvulsive therapy (ECT) is an effective treatment for all phases of BPAD, though only a few studies have focused on BPAD in the geriatric population. This study examines the safety and efficacy of ultra-brief right unilateral (UBRUL) ECT for patients with late-life bipolar depression (BD). METHODS: A retrospective chart review was conducted of patients with late-life BD who received UBRUL ECT treatments. Symptomatic response was measured using pre- and post-ECT Quick Inventory of Depressive Symptomatology (QIDS-SR16) and Beck Depression Inventory (BDI-II) scores. Clinical improvement and cognitive change were measured using Clinical Global Impression-Improvement (CGI-I) and Electroconvulsive Cognitive Assessment (ECCA) scores. RESULTS: Twenty-Seven elderly patients (mean age 69.1 ± 7.7 years) were included in the analysis. Baseline QIDS-SR16 was 17.3 ± 5.3 and BDI-II 30.0 ± 9.2. 80.0% (16/20) and 57.1% (4/7) of patients achieved response (50.0% decline) in their QIDS-SR16 and BDI-II scores, respectively. Remission rates in QIDS-SR16 (post-ECT scores ≤5) and BDI-II (post-ECT scores ≤12) were 65.0% (13/20) and 42.9% (3/7), respectively. Mean QIDS-SR16 and BDI-II scores were reduced by a statistically significant 68.2% and 50.5%, respectively (two-tailed, paired p-values <0.01) after ECT. CGI-I of ≤2 was attained by 85.2% (23/27) of patients. 85.7% (12/14) of patients saw no change or improvement in ECCA scores. LIMITATIONS: Inherent complications of chart review regarding quality, availability, and homogeny of data. CONCLUSIONS: UBRUL ECT is a safe and effective treatment for patients presenting with late-life BD.


Asunto(s)
Trastorno Bipolar , Trastorno Depresivo Mayor , Terapia Electroconvulsiva , Anciano , Trastorno Bipolar/terapia , Trastorno Depresivo Mayor/terapia , Humanos , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Estudios Retrospectivos , Resultado del Tratamiento
4.
Arch Orthop Trauma Surg ; 137(3): 393-400, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28110363

RESUMEN

BACKGROUND: Coronal deformity correction with total knee arthroplasty (TKA) is an important feature in the treatment of osteoarthritis (OA). The hypothesis of this study was that bone morphology would be different in varus and valgus deformity, both before osteoarthritis development as well as during and after the disease process of OA. MATERIALS AND METHODS: Retrospective study with measurements on preoperative and postoperative full leg standing radiographs of 96 patients who underwent TKA. The included patients were selected for this study because they had an OA knee on one side and a non-arthritic knee on the contralateral side presenting the same type of alignment as the to-be-operated knee (varus or valgus alignment on both sides). The control group of 46 subjects was a group of patients with neutral mechanical alignment who presented for ligamentous problems. A single observer measured mechanical alignment, anatomical alignment, anatomical-mechanical femoral angle and intra-articular bone morphology parameters with an accuracy of 1°. RESULTS: Varus OA group has less distal femoral valgus (mLDFA 89°) than control group (87°) and valgus OA group (mLDFA 85°). Varus OA group has same varus obliquity as control group (MPTA 87°) but more than valgus OA group (MPTA 90°). Joint Line Congruency Angle (JLCA) is 3°open on lateral side in varus and medially open in valgus OA group (2°). The non-arthritic valgus group presents a constitutional mechanical valgus of 184° Hip-Knee-Ankle (HKA) angle. DISCUSSION: Varus deformity in OA as measured with an HKA angle (HKA) <177° is a combination of distal femoral wear, tibial varus obliquity and lateral joint line opening. Valgus deformity in OA with an HKA > 183° is a combination of femoral distal joint line obliquity and wear combined with medial opening due to medial collateral ligament stretching. The clinical importance of bone morphotype analysis is that it shows the intra-articular potential of alignment correction when mechanical axis cuts are performed. CONCLUSION: Bone morphology in varus and valgus deformity is different before and after osteoarthritis. Perpendicular cuts to mechanical axes do not necessarily lead to neutral mechanical axis. Constitutional mechanical valgus was observed as 184° HKA angle before the development of OA. LEVEL OF EVIDENCE: Level IV study.


Asunto(s)
Fémur/diagnóstico por imagen , Genu Valgum/diagnóstico por imagen , Genu Varum/diagnóstico por imagen , Articulación de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/diagnóstico por imagen , Tibia/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Articulación del Tobillo/diagnóstico por imagen , Artroplastia de Reemplazo de Rodilla , Femenino , Fémur/cirugía , Articulación de la Cadera/diagnóstico por imagen , Humanos , Articulación de la Rodilla/cirugía , Extremidad Inferior/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/cirugía , Periodo Posoperatorio , Radiografía , Estudios Retrospectivos , Tibia/cirugía
5.
Knee Surg Sports Traumatol Arthrosc ; 24(10): 3346-3351, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26740088

RESUMEN

PURPOSE: To utilize the 'Forgotten Joint' Score (FJS), a 12-item questionnaire analysing the ability to forget the joint, for comparing preoperative status in osteoarthritic patients scheduled for total hip arthroplasty (THA) or total knee arthroplasty (TKA). Higher scores represent a better result with a maximum of 100. The hypothesis of this study was that a preoperative difference in favour of hip arthritis could eventually explain why THA is cited more often as a forgotten joint than TKA. METHODS: A prospective cohort study was conducted in 150 patients with either tricompartmental knee (n = 75) or hip osteoarthritis (n = 75). Patients completed FJS-12 scores preoperatively and 1 year postoperatively. RESULTS: A similar preoperative FJS-12 was observed for hip (22 (15)) and knee osteoarthritis (24 (17)) (n.s.). The postoperative FJS-12 score was significantly higher for THA (80 (24)) than for TKA (70 (27)) (p < 0.05). High reliability after 6 weeks was observed for the preoperative FJS-12 test-retest reliability (ICC = 0.87) in TKA. A preoperative floor effect of 15 % in THA and 0 % in TKA was found as well as a postoperative ceiling effect of 33 % in THA and 9 % in TKA. CONCLUSIONS: The clinical relevance of utilizing the FJS-12 as an instrument to evaluate outcome is strongly proposed for knee arthroplasty. In general, one is not aware of a healthy joint during the ADL, and it can therefore be regarded as 'forgotten'. The preoperative FJS-12 Score is a powerful tool to provide patients with clearer insights into their positive evolution after surgery. The use of the FJS-12 in THA is a topic for further research, as this study found that floor and ceiling effects limit its usefulness in studies evaluating clinical outcome in this area. LEVEL OF EVIDENCE: II.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Osteoartritis de la Cadera/cirugía , Osteoartritis de la Rodilla/cirugía , Medición de Resultados Informados por el Paciente , Encuestas y Cuestionarios , Anciano , Femenino , Articulación de la Cadera/cirugía , Humanos , Articulación de la Rodilla/cirugía , Masculino , Persona de Mediana Edad , Osteoartritis de la Cadera/diagnóstico , Osteoartritis de la Rodilla/diagnóstico , Estudios Prospectivos , Reproducibilidad de los Resultados , Resultado del Tratamiento
6.
Knee Surg Sports Traumatol Arthrosc ; 24(10): 3287-3292, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26704797

RESUMEN

PURPOSE: This study aimed to assess whether the neutrophil-to-lymphocyte ratio (NLR) distribution could have a better kinetic pattern than C-reactive protein (CRP) distribution to evaluate early post-operative inflammation after total knee arthroplasty (TKA). METHODS: A prospective study was performed on 587 patients. CRP and NLR were collected pre-operatively and at post-operative days 2, 4, 21 and 42. Mean peak values and distribution were compared between CRP and NLR. RESULTS: Mean CRP levels were 163, 161, 9 and 7 mg/L, respectively, at days 2, 4, 21 and 42. Mean NLR levels were 5, 3.5, 2.6 and 2.5, respectively, at days 2, 4, 21 and 42. At days 21 and 42, 20 % (102/503) and 21 % (93/433) of patients had not reached normal CRP levels. At day 21, there were 4.5 % (23/503) of patients with a NLR > 5 and 1 % (5/503) with an NLR > 10. At day 42, there were 5.5 % (24/433) of patients with an NLR > 5 and 0.7 % (3/433) with an NLR > 10. CONCLUSION: NLR has a faster normalization than CRP. It is potentially a better biomarker to follow post-operative inflammation or early infection after TKA. LEVEL OF EVIDENCE: II.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/efectos adversos , Proteína C-Reactiva/metabolismo , Inflamación/diagnóstico , Recuento de Leucocitos , Recuento de Linfocitos , Neutrófilos/metabolismo , Complicaciones Posoperatorias/diagnóstico , Anciano , Biomarcadores/sangre , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
7.
Bone Joint J ; 96-B(8): 1052-61, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25086121

RESUMEN

We conducted a meta-analysis, including randomised controlled trials (RCTs) and cohort studies, to examine the effect of patient-specific instruments (PSI) on radiological outcomes after total knee replacement (TKR) including: mechanical axis alignment and malalignment of the femoral and tibial components in the coronal, sagittal and axial planes, at a threshold of > 3º from neutral. Relative risks (RR) for malalignment were determined for all studies and for RCTs and cohort studies separately. Of 325 studies initially identified, 16 met the eligibility criteria, including eight RCTs and eight cohort studies. There was no significant difference in the likelihood of mechanical axis malalignment with PSI versus conventional TKR across all studies (RR = 0.84, p = 0.304), in the RCTs (RR = 1.14, p = 0.445) or in the cohort studies (RR = 0.70, p = 0.289). The results for the alignment of the tibial component were significantly worse using PSI TKR than conventional TKR in the coronal and sagittal planes (RR = 1.75, p = 0.028; and RR = 1.34, p = 0.019, respectively, on pooled analysis). PSI TKR showed a significant advantage over conventional TKR for alignment of the femoral component in the coronal plane (RR = 0.65, p = 0.028 on pooled analysis), but not in the sagittal plane (RR = 1.12, p = 0.437). Axial alignment of the tibial (p = 0.460) and femoral components (p = 0.127) was not significantly different. We conclude that PSI does not improve the accuracy of alignment of the components in TKR compared with conventional instrumentation.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/instrumentación , Desviación Ósea/prevención & control , Artroplastia de Reemplazo de Rodilla/métodos , Artroplastia de Reemplazo de Rodilla/normas , Fémur/cirugía , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Instrumentos Quirúrgicos , Tibia/cirugía , Resultado del Tratamiento
8.
Osteoporos Int ; 23(3): 829-39, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21625882

RESUMEN

UNLABELLED: In Switzerland, the number, incidence, and cost of acute hospitalizations for major osteoporotic fractures (MOF) and major cardiovascular events (MCE) increased in both women and men between 2000 and 2008, although the mean length of stay (LOS) was significantly reduced. Similar trend patterns were observed for hip fractures and strokes (decrease) and nonhip fractures and acute myocardial infarctions (increase). INTRODUCTION: The purpose of this study was to compare the trends and epidemiological characteristics of hospitalizations for MOF and other frequent diseases between years 2000 and 2008 in Switzerland. METHODS: Trends in the number, age-standardized incidence, mean LOS, and cost of hospitalized MOF and MCE (acute myocardial infarction, stroke, and heart failure) were compared in women and men aged ≥ 45 years, based on data from the Swiss Federal Statistical Office. RESULTS: Between 2000 and 2008, the incidence of acute hospitalizations for MOF increased by 3.4% in women and 0.3% in men. In both sexes, a significant decrease in hip fractures (-15.0% and -11.0%) was compensated by a concomitant, significant increase in nonhip fractures (+24.8% and +13.8%). Similarly, the incidence of acute hospitalizations for MCE increased by 4.4% in women and 8.2% in men, as an aggregated result from significantly increasing acute myocardial infarctions and significantly decreasing strokes. While the mean LOS in the acute inpatient setting decreased almost linearly between years 2000 and 2008 in all indications, the inpatient costs increased significantly (p < 0.001) for MOF (+30.1% and +42.7%) and MCE (+22.6% and +47.1%) in women and men, respectively. CONCLUSIONS: Between years 2000 and 2008, the burden of hospitalized osteoporotic fractures to the Swiss healthcare system has continued to increase in both sexes. In women, this burden was significantly higher than that of MCE and the gap widened over time.


Asunto(s)
Hospitalización/tendencias , Fracturas Osteoporóticas/epidemiología , Distribución por Edad , Anciano , Anciano de 80 o más Años , Enfermedades Cardiovasculares/economía , Enfermedades Cardiovasculares/epidemiología , Femenino , Fracturas de Cadera/economía , Fracturas de Cadera/epidemiología , Costos de Hospital/estadística & datos numéricos , Costos de Hospital/tendencias , Hospitalización/economía , Hospitalización/estadística & datos numéricos , Humanos , Incidencia , Tiempo de Internación/estadística & datos numéricos , Tiempo de Internación/tendencias , Masculino , Persona de Mediana Edad , Fracturas Osteoporóticas/economía , Factores Sexuales , Suiza/epidemiología
9.
Phys Rev Lett ; 109(24): 246604, 2012 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-23368358

RESUMEN

Theory predicts for the two-dimensional electron gas with only a Rashba spin-orbit interaction a vanishing spin Hall conductivity and at the same time a finite inverse spin Hall effect. We show how these seemingly contradictory results are compatible with the Onsager relations: The latter do hold for spin and particle (charge) currents in the two-dimensional electron gas, although (i) their form depends on the experimental setup and (ii) a vanishing bulk spin Hall conductivity does not necessarily imply a vanishing spin Hall effect. We also discuss the situation in which extrinsic spin orbit from impurities is present and the bulk spin Hall conductivity can be different from zero.

10.
Osteoporos Int ; 22(9): 2487-97, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21153020

RESUMEN

UNLABELLED: In Switzerland, the total number and incidence of hospitalizations for major osteoporotic fractures increased between years 2000 and 2007, while hospitalizations due to hip fracture decreased. The cost impact of shorter hospital stays was offset by the increasing cost per day of hospitalization. INTRODUCTION: The aim of the study was to establish the trends and epidemiological characteristics of hospitalizations for major osteoporotic fractures (MOF) between years 2000 and 2007 in Switzerland. METHODS: Sex- and age-specific trends in the number and crude and age-standardized incidences of hospitalized MOF (hip, clinical spine, distal radius, and proximal humerus) in women and men aged ≥45 years were analyzed, together with the number of hospital days and cost of hospitalization, based on data from the Swiss Federal Statistical Office hospital database and population statistics. RESULTS: Between 2000 and 2007, the absolute number of hospitalizations for MOF increased by 15.9% in women and 20.0% in men, mainly due to an increased number of non-hip fractures (+37.7% in women and +39.7% in men). Hospitalizations for hip fractures were comparatively stable (-1.8% in women and +3.3% in men). In a rapidly aging population, in which the number of individuals aged ≥45 years grew by 11.1% (women) and 14.6% (men) over the study period, the crude and age-standardized incidences of hospitalizations decreased for hip fractures and increased for non-hip MOF, both in women and men. The length of hospital stay decreased for all MOF in women and men, the cost impact of which was offset by an increase in the daily costs of hospitalization. CONCLUSIONS: Between years 2000 and 2007, hospitalizations for MOF continued to increase in Switzerland, driven by an increasing number and incidence of hospitalizations for non-hip fractures, although the incidence of hip fractures has declined.


Asunto(s)
Fracturas de Cadera/epidemiología , Hospitalización/tendencias , Tiempo de Internación/tendencias , Fracturas Osteoporóticas/epidemiología , Distribución por Edad , Anciano , Anciano de 80 o más Años , Femenino , Fracturas de Cadera/economía , Costos de Hospital/estadística & datos numéricos , Hospitalización/economía , Humanos , Tiempo de Internación/economía , Masculino , Persona de Mediana Edad , Fracturas Osteoporóticas/economía , Distribución por Sexo , Suiza/epidemiología
11.
J Phys Condens Matter ; 22(3): 036002, 2010 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-21386300

RESUMEN

We study the magnetization dynamics of a single molecular nanomagnet driven by static and variable magnetic fields within a classical treatment. The underlying analysis is valid for a regime where the energy is definitely lower than the anisotropy barrier, but still a substantial number of states are excited. We find the phase space to contain a separatrix line. Solutions far from it are oscillatory whereas the separatrix solution is of a soliton type. States near the separatrix are extremely sensitive to small perturbations, a fact that we utilize in obtaining dynamically induced magnetization switching. A new type of magnetization switching is proposed.

12.
Am J Transplant ; 8(8): 1588-92, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18557722

RESUMEN

Islet transplantation is a very promising therapy for select patients with type 1 diabetes. Continued clinical investigation is required to define the long-term safety and efficacy outcomes before the procedure will be accepted as a standard of care even for those with the most severe manifestations of diabetes. Threatening successful accomplishment of these and other innovative studies designed to advance the field are the complex financial cost accounting issues that pose undue burden on organ procurement organizations and transplant centers trying to manage the costs of the pancreata from deceased donors needed to isolate islets. Compounding the problem is the recent ruling by CMS regarding 'intent to transplant' (CMS-1543-R Dec. 21, 2006: Allocation of Donor Acquisition Costs Incurred by Organ Procurement Organizations) that does not account for the clinical need to complete the manufacturing process for islets before suitability and transplant intent of the pancreata involved can be determined. We provide a consensus document supported by a diverse group of stakeholders in islet transplantation to suggest actions to address this problem.


Asunto(s)
Trasplante de Islotes Pancreáticos/economía , Obtención de Tejidos y Órganos/economía , Humanos , Páncreas , Recolección de Tejidos y Órganos/economía
13.
Am J Transplant ; 6(2): 281-91, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16426312

RESUMEN

A national conference on organ donation after cardiac death (DCD) was convened to expand the practice of DCD in the continuum of quality end-of-life care. This national conference affirmed the ethical propriety of DCD as not violating the dead donor rule. Further, by new developments not previously reported, the conference resolved controversy regarding the period of circulatory cessation that determines death and allows administration of pre-recovery pharmacologic agents, it established conditions of DCD eligibility, it presented current data regarding the successful transplantation of organs from DCD, it proposed a new framework of data reporting regarding ischemic events, it made specific recommendations to agencies and organizations to remove barriers to DCD, it brought guidance regarding organ allocation and the process of informed consent and it set an action plan to address media issues. When a consensual decision is made to withdraw life support by the attending physician and patient or by the attending physician and a family member or surrogate (particularly in an intensive care unit), a routine opportunity for DCD should be available to honor the deceased donor's wishes in every donor service area (DSA) of the United States.


Asunto(s)
Muerte Súbita Cardíaca , Obtención de Tejidos y Órganos/ética , Adolescente , Adulto , Niño , Humanos , Trasplante de Hígado/mortalidad , Trasplante de Hígado/estadística & datos numéricos , Persona de Mediana Edad , Selección de Paciente
14.
Phys Rev Lett ; 93(20): 209701; author reply 209702, 2004 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-15600983
15.
Adv Biochem Eng Biotechnol ; 78: 75-96, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12674399

RESUMEN

A field project located at the US Naval Base at Port Hueneme, California was designed to evaluate changes in contaminant concentrations and toxicity during phytoremediation. Vegetated plots were established in petroleum (diesel and heavy oil) contaminated soil and were evaluated over a two-year period. Plant species were chosen based on initial germination studies and included native California grasses. The toxicity of the impacted soil in vegetated and unvegetated plots was evaluated using Microtox, earthworm, and seed germination assays. The reduction of toxicity was affected more by contaminant aging than the establishment of plants. However, total petroleum hydrocarbon concentrations were lower by the end of the study in the vegetated plots when compared to the unvegetated soil. Although phytoremediation is an effective approach for cleaning-up of petroleum contaminated soil, a long-term management plan is required for significant reductions in contaminant concentrations.


Asunto(s)
Biodegradación Ambiental , Petróleo/metabolismo , Petróleo/toxicidad , Raíces de Plantas/metabolismo , Poaceae/metabolismo , Contaminantes del Suelo/análisis , Bacterias/aislamiento & purificación , Disponibilidad Biológica , Biomasa , Recuento de Colonia Microbiana , Ecosistema , Contaminación Ambiental/prevención & control , Fabaceae , Desarrollo de la Planta , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/microbiología , Plantas/metabolismo , Plantas/microbiología , Poaceae/microbiología , Desarrollo de Programa , Valores de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Suelo/análisis , Microbiología del Suelo , Contaminantes del Suelo/metabolismo
17.
Appl Environ Microbiol ; 67(6): 2469-75, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11375152

RESUMEN

Plant-bacterial combinations can increase contaminant degradation in the rhizosphere, but the role played by indigenous root-associated bacteria during plant growth in contaminated soils is unclear. The purpose of this study was to determine if plants had the ability to selectively enhance the prevalence of endophytes containing pollutant catabolic genes in unrelated environments contaminated with different pollutants. At petroleum hydrocarbon contaminated sites, two genes encoding hydrocarbon degradation, alkane monooxygenase (alkB) and naphthalene dioxygenase (ndoB), were two and four times more prevalent in bacteria extracted from the root interior (endophytic) than from the bulk soil and sediment, respectively. In field sites contaminated with nitroaromatics, two genes encoding nitrotoluene degradation, 2-nitrotoluene reductase (ntdAa) and nitrotoluene monooxygenase (ntnM), were 7 to 14 times more prevalent in endophytic bacteria. The addition of petroleum to sediment doubled the prevalence of ndoB-positive endophytes in Scirpus pungens, indicating that the numbers of endophytes containing catabolic genotypes were dependent on the presence and concentration of contaminants. Similarly, the numbers of alkB- or ndoB-positive endophytes in Festuca arundinacea were correlated with the concentration of creosote in the soil but not with the numbers of alkB- or ndoB-positive bacteria in the bulk soil. Our results indicate that the enrichment of catabolic genotypes in the root interior is both plant and contaminant dependent.


Asunto(s)
Microbiología Ambiental , Genes Bacterianos , Raíces de Plantas/microbiología , Contaminantes del Suelo/metabolismo , Contaminantes del Agua/metabolismo , Bacterias/genética , Bacterias/aislamiento & purificación , Derivados del Benceno/metabolismo , Biodegradación Ambiental , Citocromo P-450 CYP4A , Sistema Enzimático del Citocromo P-450/genética , Dioxigenasas , Genotipo , Oxigenasas de Función Mixta/genética , Complejos Multienzimáticos/genética , Oxigenasas/genética , Petróleo/metabolismo , Selección Genética , Microbiología del Suelo , Trinitrotolueno/metabolismo , Microbiología del Agua
19.
Curr Rheumatol Rep ; 2(4): 297-305, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11123074

RESUMEN

A growing body of evidence suggests that T lymphocytes play an important role in initiating and maintaining the inflammatory process characteristic of the human leukocyte antigen (HLA)-B27-associated spondyloarthropathies. T cells seem to be involved in the primary defense reaction against arthritis-triggering gram-negative bacteria at the site of extra-articular infection, in determining the systemic cytokine pattern, in the recirculation process between gut mucosa and the joint, and in mediating secondary autoimmune joint inflammation. The factors involved in disease chronicity (namely in ankylosing spondylitis and psoriatic arthritis) are still unknown. Autoreactive T cells may contribute to this process by recognition of cross-reactive self-epitopes (ie, molecular mimicry between bacterial and self-antigens). Autoreactive T cells may as well be inappropriately upregulated by bacterial superantigens, or by local inflammatory reactions leading to the uncovering of former cryptic self-epitopes. In this paper, we review recent studies on peripheral blood and synovial T cells in patients with reactive arthritis, enteropathic spondyloarthropathy, psoriatic arthritis, and ankylosing spondylitis.


Asunto(s)
Espondiloartropatías/inmunología , Linfocitos T/inmunología , Artritis Psoriásica/inmunología , Artritis Reactiva/inmunología , Antígenos CD4/inmunología , Antígenos CD8/inmunología , Reacciones Cruzadas , Epítopos , Antígeno HLA-B27/inmunología , Humanos , Inflamación/inmunología , Enfermedades Inflamatorias del Intestino/complicaciones , Espondiloartropatías/etiología , Espondilitis Anquilosante/inmunología
20.
Phys Rev Lett ; 84(20): 4779, 2000 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-10990796
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