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1.
Artículo en Inglés | MEDLINE | ID: mdl-38545626

RESUMEN

BACKGROUND: Compared with the general population, adults with an intellectual developmental disorder (IDD) are more likely to develop mental health problems and to receive high levels of psychotropic medication, particularly antipsychotics. The emotional development (ED) approach may help to better understand the nature of challenging behaviour (CB) and tailor treatment and support accordingly. The aim of this retrospective study was to investigate the impact of the ED approach on the prescription of psychotropic medication during inpatient psychiatric treatment. METHODS: The clinical data of 1758 patients were analysed within a retrospective study design over a period of 12 years. ED level was assessed (1) for the first time (INITIAL-SEO), (2) during a previous hospital stay (PAST-SEO) or (3) not at all (NO-SEO). The effects of the ED assessment and the respective intervention during the current admission on the number of psychotropics and the number and dosage of antipsychotics were analysed for the total sample, including those with CB, autism spectrum disorders and psychosis. Group differences were analysed by a chi-square test and a one-factorial analysis of variance. For analysing the impact of the application of the ED approach on psychotropic medication, a covariance model was applied. Changes between the subsamples were analysed by t-tests for dependent samples. RESULTS: The ED approach had a significant impact on reducing the overall amount of psychotropic medication and the dosage of antipsychotics in all patients with IDD. These effects were mainly attributable to those showing CB. In patients with autism spectrum disorders, the developmental approach reduced the number of antipsychotics. No effects could be observed in patients with psychosis; in this subsample, both the number and dosage of antipsychotics increased. CONCLUSIONS: The application of the ED approach in the current hospital stay reduced the number of psychotropic drugs and the number and dosage of antipsychotics, especially in those patients with IDD and CB, but also in those with autism spectrum disorders.

2.
Arch Orthop Trauma Surg ; 142(12): 3917-3925, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34964068

RESUMEN

INTRODUCTION: An increased tibial slope is a risk factor for rupture of the anterior cruciate ligament. In addition, a tibial bone bruise or posterior lateral impression associated with slope changes also poses chronic ligamentous instability of the knee joint associated with an anterior cruciate ligament (ACL) injury. In the majority of cases, the slope is measured in one plane X-ray in the lateral view. However, this does not sufficient represent the complex anatomy of the tibial plateau and especially for the posterolateral quadrant. Normal values from a "healthy" population are necessary to understand if stability of the knee joint is negatively affected by an increasing slope in the posterolateral area. Until now there are no data about the physiological slope in the posterolateral quadrant of the tibial plateau. MATERIALS AND METHODS: In 116 MRI scans of patients without ligamentous lesions and 116 MRI scans with an ACL rupture, tibial slope was retrospectively determined using the method described by Hudek et al. Measurements were made in the postero-latero-lateral (PLL) and postero-latero-central (PLC) segments using the 10-segment classification. In both segments, the osseous as well as the cartilaginous slope was measured. Measurements were performed by two independent surgeons. RESULTS: In the group without ligamentous injury the mean bony PLL slope was 5.8° ± 4.8° and the cartilaginous PLL slope was 6.7° ± 4.8°. In the PLC segment the mean bony slope was 6.6° ± 5.0° and the cartilaginous slope was 9.4° ± 5.7°. In the cohort with ACL rupture, the bony and cartilaginous slope in both PLL and PCL were significantly higher (P < 0.001) than in the group without ACL injury (bony PLL 9.8° ± 4.8°, cartilage PLL 10.4° ± 4.7°, bony PLC 10.3° ± 4.8°, cartilage PLL 12.8° ± 4.3°). Measurements were performed independently by two experienced surgeons. There were good inter- (CI 87-98.7%) and good intraobserver (CI 85.8-99.6%) reliability. CONCLUSION: The bony and the cartilaginous slope in the posterolateral quadrant of the tibial plateau are different but not independent. Patients with an anterior cruciate ligament injury have a significantly steeper slope in the posterolateral quadrant compared to a healthy group. Our data indicate that this anatomic feature might be a risk factor for a primary ACL injury which has not been described yet. LEVEL OF EVIDENCE: III.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Traumatismos de la Rodilla , Humanos , Lesiones del Ligamento Cruzado Anterior/diagnóstico por imagen , Lesiones del Ligamento Cruzado Anterior/cirugía , Traumatismos de la Rodilla/cirugía , Estudios Retrospectivos , Reproducibilidad de los Resultados , Tibia/cirugía , Articulación de la Rodilla/cirugía , Imagen por Resonancia Magnética
4.
Nat Commun ; 12(1): 922, 2021 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-33568657

RESUMEN

Giant exoplanets on wide orbits have been directly imaged around young stars. If the thermal background in the mid-infrared can be mitigated, then exoplanets with lower masses can also be imaged. Here we present a ground-based mid-infrared observing approach that enables imaging low-mass temperate exoplanets around nearby stars, and in particular within the closest stellar system, α Centauri. Based on 75-80% of the best quality images from 100 h of cumulative observations, we demonstrate sensitivity to warm sub-Neptune-sized planets throughout much of the habitable zone of α Centauri A. This is an order of magnitude more sensitive than state-of-the-art exoplanet imaging mass detection limits. We also discuss a possible exoplanet or exozodiacal disk detection around α Centauri A. However, an instrumental artifact of unknown origin cannot be ruled out. These results demonstrate the feasibility of imaging rocky habitable-zone exoplanets with current and upcoming telescopes.

5.
BMC Musculoskelet Disord ; 21(1): 693, 2020 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-33076902

RESUMEN

BACKGROUND: Osteoporosis affects elderly patients of both sexes. It is characterized by an increased fracture risk due to defective remodeling of the bone microarchitecture. It affects in particular postmenopausal women due to their decreased levels of estrogen. Preclinical studies with animals demonstrated that loss of estrogen had a negative effect on bone healing and that increasing the estrogen level led to a better bone healing. We asked whether increasing the estrogen level in menopausal patients has a beneficial effect on bone mineral density (BMD) during callus formation after a bone fracture. METHODS: To investigate whether estrogen has a beneficial effect on callus BMD of postmenopausal patients, we performed a prospective double-blinded randomized study with 76 patients suffering from distal radius fractures. A total of 31 patients (71.13 years ±11.99) were treated with estrogen and 45 patients (75.62 years ±10.47) served as untreated controls. Calculated bone density as well as cortical bone density were determined by peripheral quantitative computed tomography (pQCT) prior to and 6 weeks after the surgery. Comparative measurements were performed at the fractured site and at the corresponding position of the non-fractured arm. RESULTS: We found that unlike with preclinical models, bone fracture healing of human patients was not improved in response to estrogen treatment. Furthermore, we observed no dependence between age-dependent bone tissue loss and constant callus formation in the patients. CONCLUSIONS: Transdermally applied estrogen to postmenopausal women, which results in estrogen levels similar to the systemic level of premenopausal women, has no significant beneficial effect on callus BMD as measured by pQCT, as recently shown in preclinical animal models. TRIAL REGISTRATION: Low dose estrogen has no significant effect on bone fracture healing measured by pQCT in postmenopausal women, DRKS00019858 . Registered 25th November 2019 - Retrospectively registered. Trial registration number DRKS00019858 .


Asunto(s)
Densidad Ósea , Osteoporosis Posmenopáusica , Anciano , Callo Óseo/diagnóstico por imagen , Estrógenos , Femenino , Humanos , Masculino , Osteoporosis Posmenopáusica/diagnóstico por imagen , Osteoporosis Posmenopáusica/tratamiento farmacológico , Posmenopausia , Estudios Prospectivos
6.
MethodsX ; 7: 100944, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32566491

RESUMEN

A temporal framework for mineral deposits is essential when addressing the history of their formation and conceptualizing genetic models of their origin. This knowledge is critical to understand how crust-forming processes are related to metal accumulations at specific time and conditions of Earth evolution. To this end, high-precision absolute geochronology utilising the rhenium-osmium (Re-Os) radiometric system in specific sulphide minerals is becoming a method of choice. Here, we present a procedure to obtain mineral separates of individual sulphide species that may coexist within specific mineralized horizons in ore deposits. This protocol is based on preliminary petrographic and paragenetic investigations of sulphide and gangue minerals using reflected and transmitted light microscopy. Our approach emphasizes the key role of a stepwise use of a Frantz isodynamic separator to produce mineral separates of individual sulphide species that are subsequently processed for Re-Os and sulphur isotope geochemistry.•Detailed method and its graphical illustration modified from an original procedure introduced by [1], [2].•Quality control and validation of monophasic mineral separates made by microscopic investigations and qualitative analysis of aliquots embedded in epoxy mounts.•The present method, which contributed to the successful results presented in the co-publication by Saintilan et al. (2020), demonstrates why other studies reporting Re-Os isotope data for mixtures of sulphide minerals should be considered with caution.

7.
Eur Biophys J ; 46(6): 567-580, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28365791

RESUMEN

Nanosecond pulsed electric fields (nsPEFs) applied to cells can induce different biological effects depending on pulse duration and field strength. One known process is the induction of apoptosis whereby nsPEFs are currently investigated as a novel cancer therapy. Another and probably related change is the breakdown of the cytoskeleton. We investigated the elasticity of rat liver epithelial cells WB-F344 in a monolayer using atomic force microscopy (AFM) with respect to the potential of cells to undergo malignant transformation or to develop a potential to metastasize. We found that the elastic modulus of the cells decreased significantly within the first 8 min after treatment with 20 pulses of 100 ns and with a field strength of 20 kV/cm but was still higher than the elasticity of their tumorigenic counterpart WB-ras. AFM measurements and immunofluorescent staining showed that the cellular actin cytoskeleton became reorganized within 5 min. However, both a colony formation assay and a cell migration assay revealed no significant changes after nsPEF treatment, implying that cells seem not to adopt malignant characteristics associated with metastasis formation despite the induced transient changes to elasticity and cytoskeleton that can be observed for up to 1 h.


Asunto(s)
Carcinogénesis , Elasticidad , Electricidad , Actinas/metabolismo , Línea Celular , Movimiento Celular , Proliferación Celular , Metástasis de la Neoplasia , Factores de Tiempo
9.
Orthopade ; 44(9): 672-680, 2015 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-26193968

RESUMEN

BACKGROUND: Vertebral compression fractures are the most common osteoporotic fractures. Since the introduction of vertebroplasty and screw augmentation, the management of osteoporotic fractures has changed significantly. AIMS: The biomechanical characteristics of the risk of adjacent fractures and novel treatment modalities for osteoporotic vertebral fractures, including pure cement augmentation by vertebroplasty, and cement augmentation of screws for posterior instrumentation, are explored. MATERIALS AND METHODS: Eighteen human osteoporotic lumbar spines (L1-5) adjacent to vertebral bodies after vertebroplasty were tested in a servo-hydraulic machine. As augmentation compounds we used standard cement and a modified low-strength cement. Different anchoring pedicle screws were tested with and without cement augmentation in another cohort of human specimens with a simple pull-out test and a fatigue test that better reflects physiological conditions. RESULTS: Cement augmentation in the osteoporotic spine leads to greater biomechanical stability. However, change in vertebral stiffness resulted in alterations with the risk of adjacent fractures. By using a less firm cement compound, the risk of adjacent fractures is significantly reduced. Both screw augmentation techniques resulted in a significant increase in the withdrawal force compared with the group without cement. Augmentation using perforated screws showed the highest stability in the fatigue test. DISCUSSION AND CONCLUSION: The augmentation of cement leads to a significant change in the biomechanical properties. Differences in the stability of adjacent vertebral bodies increase the risk of adjacent fractures, which could be mitigated by a modified cement compound with reduced strength. Screws that were specifically designed for cement application displayed greatest stability in the fatigue test.


Asunto(s)
Cementos para Huesos/uso terapéutico , Fracturas Osteoporóticas/fisiopatología , Fracturas Osteoporóticas/terapia , Fracturas de la Columna Vertebral/fisiopatología , Fracturas de la Columna Vertebral/terapia , Vertebroplastia/instrumentación , Anciano , Tornillos Óseos , Terapia Combinada/métodos , Femenino , Fricción , Humanos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/lesiones , Vértebras Lumbares/cirugía , Masculino , Fracturas Osteoporóticas/diagnóstico por imagen , Radiografía , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fusión Vertebral/instrumentación , Fusión Vertebral/métodos , Estrés Mecánico , Resultado del Tratamiento , Vertebroplastia/métodos
10.
Bone Joint J ; 95-B(11): 1527-32, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24151274

RESUMEN

A combined anterior and posterior surgical approach is generally recommended in the treatment of severe congenital kyphosis, despite the fact that the anterior vascular supply of the spine and viscera are at risk during exposure. The aim of this study was to determine whether the surgical treatment of severe congenital thoracolumbar kyphosis through a single posterior approach is feasible, safe and effective. We reviewed the records of ten patients with a mean age of 11.1 years (5.4 to 14.1) who underwent surgery either by pedicle subtraction osteotomy or by vertebral column resection with instrumented fusion through a single posterior approach. The mean kyphotic deformity improved from 59.9° (45° to 110°) pre-operatively to 17.5° (3° to 40°) at a mean follow-up of 47.0 months (29 to 85). Spinal cord monitoring was used in all patients and there were no complications during surgery. These promising results indicate the possible advantages of the described technique over the established procedures. We believe that surgery should be performed in case of documented progression and before structural secondary curves develop. Our current strategy after documented progression is to recommend surgery at the age of five years and when 90% of the diameter of the spinal canal has already developed.


Asunto(s)
Cifosis/congénito , Cifosis/cirugía , Vértebras Lumbares/cirugía , Osteotomía/métodos , Complicaciones Posoperatorias/etiología , Vértebras Torácicas/cirugía , Adolescente , Niño , Preescolar , Femenino , Estudios de Seguimiento , Alemania , Humanos , Masculino , Osteotomía/efectos adversos , Complicaciones Posoperatorias/epidemiología , Resultado del Tratamiento
11.
Injury ; 44(6): 802-7, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23545113

RESUMEN

INTRODUCTION: Proximal femoral fractures will gain increasing importance in the future due to the epidemiological development. Osteoporosis is often a limiting factor in the achievement of implant stability. New nailing systems offer the possibility of augmentation of the femoral neck component with cement. The aim of this study was to perform a biomechanical comparison of implant stability in osteoporotic pertrochanteric fractures using the proximal femoral nail antirotation (PFNA, Synthes GmbH, Umkirch, Germany) with cement augmented and non-augmented blades. MATERIALS AND METHODS: Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry (DEXA) in six pairs of fresh-frozen human femurs. Standardised pertrochanteric fractures (AO31-A2.3) were treated with a PFNA. Cement augmentation was performed in six constructs. Axial loading was applied according to a single-leg-stance model using a hydraulic testing machine increasing to 1400N over 10,000 cycles. Biomechanical comparisons between the two groups that were comparable concerning BMD, tip-apex-distance and native stiffness were made with regard to postoperative stiffness, survived cycles, load to failure, failure mechanism and axial displacement. RESULTS: The stiffness of all stabilised femurs was significantly lower than for native specimens (native 702.5±159.6N/mm vs. postoperative 275.4±53.8N/mm, p<0.001). Stiffness after instrumentation was significantly greater for the cement augmented group than for the non-augmented group (300.6±46.7N/mm vs. 250.3±51.6N/mm, respectively, p=0.001). Five of the twelve constructs survived cyclic testing. Statistically significant differences of the BMD were detected between survived and failed constructs (0.79±0.17g/cm(2) vs. 0.45±0.12g/cm(2), respectively, p=0.028). The failure loads for specimens surviving 10,000 cycles were 4611.9±2078.9N in the cement augmented group (n=3) and 4516.3N and 3253.5N in the non-augmented group (n=2). Postoperative stiffness was found to be a positive predictor of maximum force to failure (R(2)=0.83, p=0.02). CONCLUSIONS: The results of this biomechanical study show that cement augmentation of the PFNA increases the implant stability in osteoporotic pertrochanteric fractures. Further studies are necessary to evaluate this procedure in providing long term clinical results.


Asunto(s)
Cementos para Huesos , Clavos Ortopédicos , Fracturas del Fémur/cirugía , Fijación Intramedular de Fracturas/métodos , Fracturas Osteoporóticas/cirugía , Absorciometría de Fotón , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Densidad Ósea , Placas Óseas , Cadáver , Femenino , Fijación Intramedular de Fracturas/instrumentación , Humanos , Masculino , Ensayo de Materiales
12.
Arch Orthop Trauma Surg ; 133(2): 187-92, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23179475

RESUMEN

INTRODUCTION: Recent studies suggest that calcium and 25-[OH]-cholecalciferol represent substantial co-factors in fracture healing. However, there still seems to be no sustainable consensus regarding the influence on fracture healing patterns. In this study, the influence of calcium and vitamin D levels on fracture callus formation was prospectively analysed using pQCT scan. METHODS: 94 postmenopausal females with distal radius fractures and consecutive surgery were included. Calcium, 25-[OH]-cholecalciferol, parathyroid hormone and bone-specific alkaline phosphatase levels were obtained prior surgical treatment and after 6 weeks. A pQCT scan was performed on both sites. Bone mineral density and fracture callus area were determined after detecting the outer border contour at a threshold of 280 mg/ccm. Patients received daily supplements of 1000 mg calcium and 880 IU 25-[OH]-cholecalciferol. RESULTS: Mean 25-[OH]-cholecalciferol level was 19.61 ± 21.87 ng/ml, mean parathyroid hormone level was 52.6 ± 58.9 ng/l and mean Ca level was 2.23 ± 0.35 mmol/l. After 6 weeks of supplementation a significant increase of calcium (p < 0.001) and 25-[OH]-cholecalciferol (p < 0.001), and a significant decrease of parathyroid hormone (p < 0.001) levels were observed. Sixth week follow-up fracture callus area correlated significantly with postoperative normal range calcium levels on the fractured site (p = 0.006). Bone mineral density correlated with age (p < 0.001), but not with calcium and 25-[OH]-cholecalciferol levels after 6 weeks. All fractures presented timely adequate callus formation. CONCLUSION: Calcium and parathyroid hormone serum levels influence fracture callus area interpreted as fracture callus formation patterns. Calcium levels within physiological range accounted for highest fracture callus area. Therefore, a balanced calcium homeostasis is required for appropriate callus formation.


Asunto(s)
Calcifediol/sangre , Calcio/sangre , Curación de Fractura/fisiología , Hormona Paratiroidea/sangre , Fracturas del Radio/sangre , Fracturas del Radio/fisiopatología , Anciano , Anciano de 80 o más Años , Fosfatasa Alcalina/sangre , Densidad Ósea , Callo Óseo/fisiopatología , Calcifediol/uso terapéutico , Calcio/uso terapéutico , Suplementos Dietéticos , Femenino , Homeostasis , Humanos , Persona de Mediana Edad , Posmenopausia , Fracturas del Radio/cirugía , Tomografía Computarizada por Rayos X
13.
Br J Surg ; 99 Suppl 1: 122-30, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22441866

RESUMEN

BACKGROUND: Early diagnosis and prediction of traumatic brain injury (TBI) is essential for determining treatment strategies and allocating resources. This study evaluated the predictive accuracy of Glasgow Coma Scale (GCS) verbal, motor and eye components alone, or in addition to pupil size and reactivity, for TBI. METHODS: A retrospective cohort analysis of data from 51 425 severely injured patients registered in the Trauma Registry of the German Society for Trauma Surgery from 1993 to 2009 was undertaken. Only directly admitted patients alive on admission and with complete data on GCS, pupil size and pupil reactivity were included. The unadjusted predictive roles of GCS components and pupil parameters, alone or in combination, were modelled using area under the receiver operating characteristic (AUROC) curve analyses and multivariable logistic regression regarding presence of TBI and death. RESULTS: Some 24 115 patients fulfilled the study inclusion criteria. Best accuracy for outcome prediction was found for pupil reactivity (AUROC 0.770, 95 per cent confidence interval 0.761 to 0.779) and GCS motor component (AUROC 0.797, 0.788 to 0.805), with less accuracy for GCS eye and verbal components. The combination of pupil reactivity and GCS motor component (AUROC 0.822, 0.814 to 0.830) outmatched the predictive accuracy of GCS alone (AUROC 0.808, 0.800 to 0.815). Pupil reactivity and size were significantly correlated (r(s) = 0.56, P < 0.001). Patients displaying both unequal pupils and fixed pupils were most likely to have TBI (95.1 per cent of 283 patients). Good outcome (Glasgow Outcome Scale score 4 or more) was documented for only 1929 patients (8.0 per cent) showing fixed and bilateral dilated pupils. CONCLUSION: The best predictive accuracy for presence of TBI was obtained using the GCS components. Pupil reactivity together with the GCS motor component performed best in predicting death.


Asunto(s)
Lesiones Encefálicas/diagnóstico , Escala de Coma de Glasgow/normas , Reflejo Pupilar/fisiología , Adulto , Lesiones Encefálicas/mortalidad , Diagnóstico Precoz , Femenino , Hospitalización , Humanos , Masculino , Pronóstico , Curva ROC
14.
Technol Cancer Res Treat ; 11(1): 83-93, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22181334

RESUMEN

Novel therapies are needed for treating hepatocellular carcinoma (HCC) without recurrence in a single procedure. In this work we evaluated anti-neoplastic effects of a pulse power ablation (PPA) with nanosecond pulsed electric fields (nsPEFs), a non-thermal, non-drug, local, regional method and investigated its molecular mechanisms for hepatocellular carcinoma tumor ablation in vivo. An ectopic tumor model was established using C57BL/6 mice with Hepa1-6 hepatocellular carcinoma cells. Pulses with durations of 30 or 100 ns and fast rise times were delivered by a needle or ring electrode with different electric field strengths (33, 50 and 68 kV/cm), and 900 pulses in three treatment sessions (300 pulses each session) or a single 900 pulse treatment. Treated and control tumor volumes were monitored by ultrasound and apoptosis and angiogenesis markers were evaluated by immunohistochemistry. Seventy five percent of primary hepatocellular carcinoma tumors were eradicated with 900 hundred pulses at 100 ns pulses at 68 kV/cm in a single treatment or in three treatment sessions without recurrence within 9 months. Using quantitative analysis, tumors in treated animals showed nsPEF-mediated nuclear condensation (3 h post-pulse), cell shrinkage (1 h), increases in active executioner caspases (caspase-3 > -7 > -6) and terminal deoxynucleotidyl transferase dUTP nick-end-labeling (1 h) with decreases in vascular endothelial growth factor expression (7d) and micro-vessel density (14d). NsPEF ablation eliminated hepatocellular carcinoma tumors by targeting two therapeutic sites, apoptosis induction and inhibition of angiogenesis, both important cancer hallmarks. These data indicate that PPA with nsPEFs is not limited to treating skin cancers and provide a rationale for continuing to investigate pulse power ablation for hepatocellular carcinoma using other models in pre-clinical applications and ultimately in clinical trials. Based on present treatments for specific HCC stages, it is anticipated that nsPEFs could be substituted for or used in combination with ablation therapies using heat, cold or chemicals.


Asunto(s)
Carcinoma Hepatocelular/terapia , Ablación por Catéter/métodos , Neoplasias Hepáticas/terapia , Animales , Apoptosis/efectos de la radiación , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Modelos Animales de Enfermedad , Campos Electromagnéticos , Etiquetado Corte-Fin in Situ , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Ratones , Ratones Endogámicos C57BL , Trasplante de Neoplasias
15.
Lett Appl Microbiol ; 54(2): 126-32, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22122358

RESUMEN

AIMS: Multidrug-resistant opportunistic pathogens are clinically significant and require the development of new antimicrobial methods. In this study, Acinetobacter baumannii, Pseudomonas aeruginosa and Staphylococcus aureus cells were exposed to atmospheric plasma on agar plates and in vitro on porcine skin for the purpose of testing bacterial inactivation. METHODS AND RESULTS: Microbial inactivation at varying exposure durations was tested using a nonthermal plasma jet generated with a DC voltage from ambient air. The observed reduction in colony forming units was quantified as log(10) reductions. CONCLUSIONS: Direct plasma exposure significantly inactivated seeded bacterial cells by approx. 6 log(10) on agar plates and 2-3 log(10) on porcine skin. On agar plates, an indirect 'bystander' inactivation outside the plasma delivery area was also observed. The reduced inactivation observed on the skin surface was most likely due to cell protection by the variable surface architecture. SIGNIFICANCE AND IMPACT OF STUDY: Atmospheric plasma has potential for clinical application as a disinfectant of patient skin and medically relevant surfaces.


Asunto(s)
Fenómenos Fisiológicos Bacterianos , Viabilidad Microbiana , Piel/microbiología , Acinetobacter baumannii/fisiología , Animales , Electricidad , Humanos , Pseudomonas aeruginosa/fisiología , Esporas Bacterianas/fisiología , Staphylococcus aureus/fisiología , Porcinos
16.
Vet Rec ; 169(21): 553, 2011 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-21949083

RESUMEN

This study evaluated the use of an avirulent live Salmonella Choleraesuis vaccine to reduce the seroprevalence and number of Salmonella carrier pigs at slaughter. Seven batches of 500 pigs were included in each of the two study groups: the vaccinated group (VG) that was orally vaccinated and the control group (CG) that received a placebo on the first day of life. The groups were managed in a three-site system and followed up from birth to slaughter. Blood samples (n=378) were collected from each VG and CG to monitor the on-farm seroprevalence in both groups. Mesenteric lymph nodes and blood from animals (n=390) belonging to each group were collected at slaughter. At the first day of life, the seroprevalence in control batches ranged from 77.9 to 96.3 per cent, while in vaccinated batches, it ranged from 66.6 to 92.6 per cent. At weaning (21 days of age), the number of seropositives decreased in both groups (mean of 12 and 3.7 per cent for CG and VG, respectively). At slaughter, batches of VG had a significantly (P<0.0001) lower seroprevalence (46.6±5 per cent) and isolation of Salmonella from lymph nodes (33.1±5 per cent) compared with CG batches (79.7±4 per cent and 59.5±5 per cent, respectively). The results indicate that administration of a Salmonella choleraesuis-attenuated vaccine on the first day of life decreases Salmonella isolation and seroprevalence in pigs at slaughter.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Salmonelosis Animal/prevención & control , Vacunas contra la Salmonella/inmunología , Enfermedades de los Porcinos/prevención & control , Animales , Animales Recién Nacidos , Portador Sano/prevención & control , Portador Sano/veterinaria , Distribución Aleatoria , Salmonella/inmunología , Estudios Seroepidemiológicos , Porcinos , Vacunas Atenuadas , Virulencia
17.
Bioelectrochemistry ; 82(2): 131-4, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21719360

RESUMEN

We investigated the effects of nanosecond pulsed electric fields (nsPEF) on three human cell lines and demonstrated cell shrinkage, breakdown of the cytoskeleton, nuclear membrane and chromosomal telomere damage. There was a differential response between cell types coinciding with cell survival. Jurkat cells showed cytoskeleton, nuclear membrane and telomere damage that severely impacted cell survival compared to two adherent cell lines. Interestingly, disruption of the actin cytoskeleton in adherent cells prior to nsPEF exposure significantly reduced cell survival. We conclude that nsPEF applications are able to induce damage to the cytoskeleton and nuclear membrane. Telomere sequences, regions that tether and stabilize DNA to the nuclear membrane, are severely compromised as measured by a pan-telomere probe. Internal pore formation following nsPEF applications has been described as a factor in induced cell death. Here we suggest that nsPEF induced physical changes to the cell in addition to pore formation need to be considered as an alternative method of cell death. We suggest nsPEF electrochemical induced depolymerization of actin filaments may account for cytoskeleton and nuclear membrane anomalies leading to sensitization.


Asunto(s)
Citoesqueleto/ultraestructura , Electroporación , Membrana Nuclear/ultraestructura , Telómero/ultraestructura , Línea Celular , Supervivencia Celular , Electricidad , Células HeLa , Humanos , Células Jurkat
18.
Biochem Pharmacol ; 78(5): 514-22, 2009 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-19433065

RESUMEN

CD80/B7.1 expressed on monocytes plays a prominent role in the activation of T cell-mediated immunity and its level is reduced in monocytes from cancer patients. Type I (alpha/beta) and type II (gamma) IFNs are widely administered as adjuvant therapy. We show here that both classes of IFNs upregulate CD80 mRNA and protein in primary monocytes ex vivo. The stimulatory action of IFN-alpha/beta on CD80 is accompanied by the activation of both interferon regulatory factors IRF-1 and IRF-7, whereas IFN-gamma stimulating effect is associated only with IRF-1 induction. IFNs concomitantly upregulate the transcription of CD40 costimulatory molecule whose activation is known to require IRF-1. In monocytic U937 cells, IRF-1 is activated by IFN-gamma but not by IFN-alpha/beta, whereas it is the reverse for IRF-7; in the latter cells, only IFN-gamma is capable of stimulating CD80 transcription emphasizing the essential role of IRF-1. Moreover, siRNA against IRF-1 prevents IFN-gamma-mediated CD80 activation. In AML cells, IFNs upregulate CD40, CD80 and IRF-1 in the FAB-M4/M5 subtypes but not in the less differentiated M1/M2 subtypes. Monitoring the expression of CD80 on AML cells and its modulation by IFNs could help to predict the patients more susceptible to benefit from therapeutic strategies aimed at eliciting specific T cell responses to leukemia-associated antigens.


Asunto(s)
Antígeno B7-1/fisiología , Factor 1 Regulador del Interferón/fisiología , Interferón Tipo I/fisiología , Interferón gamma/fisiología , Monocitos/metabolismo , Regulación hacia Arriba/fisiología , Secuencia de Bases , Cartilla de ADN , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
20.
Leuk Res ; 32(12): 1914-26, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18656257

RESUMEN

A series of 10 heterocyclic compounds purified from Allanblackia were tested on two B cell lines, ESKOL and EHEB, and on cells from B-CLL patients. Several molecules inhibited the proliferation of both cell lines and promoted apoptosis of B-CLL cells through different mechanisms, some of them elicited a dissipation of the mitochondrial transmembrane potential, other triggered caspase-3 activation and cleavage of the inducible nitric oxide synthase. Blood mononuclear cells and B-lymphocytes from healthy donors appeared less sensitive than B-CLL cells. These results indicate that these molecules may be of interest in the development of new therapies for B-CLL.


Asunto(s)
Compuestos Heterocíclicos/farmacología , Leucemia Linfocítica Crónica de Células B/patología , Malpighiaceae/química , Xantonas/farmacología , Anciano , Anciano de 80 o más Años , Caspasa 3/efectos de los fármacos , Caspasa 3/metabolismo , División Celular/efectos de los fármacos , Femenino , Estudios de Seguimiento , Compuestos Heterocíclicos/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Membranas Mitocondriales/efectos de los fármacos , Membranas Mitocondriales/fisiología , Permeabilidad/efectos de los fármacos , Raíces de Plantas/química , Células Tumorales Cultivadas , Xantonas/aislamiento & purificación
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