ABSTRACT
The RABiT (Rapid Automated Biodosimetry Tool) is a dedicated Robotic platform for the automation of cytogenetics-based biodosimetry assays. The RABiT was developed to fulfill the critical requirement for triage following a mass radiological or nuclear event. Starting from well-characterized and accepted assays we developed a custom robotic platform to automate them. We present here a brief historical overview of the RABiT program at Columbia University from its inception in 2005 until the RABiT was dismantled at the end of 2015. The main focus of this paper is to demonstrate how the biological assays drove development of the custom robotic systems and in turn new advances in commercial robotic platforms inspired small modifications in the assays to allow replacing customized robotics with 'off the shelf' systems. Currently, a second-generation, RABiT II, system at Columbia University, consisting of a PerkinElmer cell::explorer, was programmed to perform the RABiT assays and is undergoing testing and optimization studies.
Subject(s)
Biological Assay/instrumentation , Chromosome Aberrations/radiation effects , Flow Cytometry/instrumentation , Radiometry/instrumentation , Robotics/instrumentation , Specimen Handling/instrumentation , Biological Assay/methods , Equipment Design , Equipment Failure Analysis , Humans , Pattern Recognition, Automated/methods , Radiation Dosage , Radiometry/trends , Robotics/methods , Specimen Handling/methodsABSTRACT
The biological risks associated with low-dose-rate (LDR) radiation exposures are not yet well defined. To assess the risk related to DNA damage, we compared the yields of two established biodosimetry end points, γ-H2AX and micronuclei (MNi), in peripheral mouse blood lymphocytes after prolonged in vivo exposure to LDR X rays (0.31 cGy/min) vs. acute high-dose-rate (HDR) exposure (1.03 Gy/min). C57BL/6 mice were total-body irradiated with 320 kVP X rays with doses of 0, 1.1, 2.2 and 4.45 Gy. Residual levels of total γ-H2AX fluorescence in lymphocytes isolated 24 h after the start of irradiation were assessed using indirect immunofluorescence methods. The terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay was used to determine apoptotic cell frequency in lymphocytes sampled at 24 h. Curve fitting analysis suggested that the dose response for γ-H2AX yields after acute exposures could be described by a linear dependence. In contrast, a linear-quadratic dose-response shape was more appropriate for LDR exposure (perhaps reflecting differences in repair time after different LDR doses). Dose-rate sparing effects (P < 0.05) were observed at doses ≤2.2 Gy, such that the acute dose γ-H2AX and TUNEL-positive cell yields were significantly larger than the equivalent LDR yields. At the 4.45 Gy dose there was no difference in γ-H2AX expression between the two dose rates, whereas there was a two- to threefold increase in apoptosis in the LDR samples compared to the equivalent 4.45 Gy acute dose. Micronuclei yields were measured at 24 h and 7 days using the in vitro cytokinesis-blocked micronucleus (CBMN) assay. The results showed that MNi yields increased up to 2.2 Gy with no further increase at 4.45 Gy and with no detectable dose-rate effect across the dose range 24 h or 7 days post exposure. In conclusion, the γ-H2AX biomarker showed higher sensitivity to measure dose-rate effects after low-dose LDR X rays compared to MNi formation; however, confounding factors such as variable repair times post exposure, increased cell killing and cell cycle block likely contributed to the yields of MNi with accumulating doses of ionizing radiation.
Subject(s)
DNA Damage/radiation effects , Dose-Response Relationship, Radiation , Histones/biosynthesis , Lymphocytes/radiation effects , Animals , Apoptosis/radiation effects , Cell Cycle/radiation effects , Cell Survival/radiation effects , Gene Expression Regulation/radiation effects , Mice , Whole-Body Irradiation , X-RaysABSTRACT
At the Center for High-Throughput Minimally Invasive Radiation Biodosimetry, we have developed a rapid automated biodosimetry tool (RABiT); this is a completely automated, ultra-high-throughput robotically based biodosimetry workstation designed for use following a large-scale radiological event, to perform radiation biodosimetry measurements based on a fingerstick blood sample. High throughput is achieved through purpose built robotics, sample handling in filter-bottomed multi-well plates and innovations in high-speed imaging and analysis. Currently, we are adapting the RABiT technologies for use in laboratory settings, for applications in epidemiological and clinical studies. Our overall goal is to extend the RABiT system to directly measure the kinetics of DNA repair proteins. The design of the kinetic/time-dependent studies is based on repeated, automated sampling of lymphocytes from a central reservoir of cells housed in the RABiT incubator as a function of time after the irradiation challenge. In the present study, we have characterized the DNA repair kinetics of the following repair proteins: γ-H2AX, 53-BP1, ATM kinase, MDC1 at multiple times (0.5, 2, 4, 7 and 24 h) after irradiation with 4 Gy γ rays. In order to provide a consistent dose exposure at time zero, we have developed an automated capillary irradiator to introduce DNA DSBs into fingerstick-size blood samples within the RABiT. To demonstrate the scalability of the laboratory-based RABiT system, we have initiated a population study using γ-H2AX as a biomarker.
Subject(s)
DNA Breaks, Double-Stranded/radiation effects , DNA Repair/radiation effects , Radiometry/methods , Adaptor Proteins, Signal Transducing , Adult , Ataxia Telangiectasia Mutated Proteins/metabolism , Biomarkers/metabolism , Cell Cycle Proteins , Cesium Radioisotopes/adverse effects , Gamma Rays , Histones/metabolism , Humans , Intracellular Signaling Peptides and Proteins/metabolism , Kinetics , Male , Middle Aged , Nuclear Proteins/metabolism , Radiometry/instrumentation , Time Factors , Trans-Activators/metabolism , Tumor Suppressor p53-Binding Protein 1ABSTRACT
BACKGROUND: To describe the pattern of patients admitted due to rare diseases corresponding to congenital anomalies in a regional hospital. METHODS: Retrospective transversal study. We considered hospital discharges for the years 2009-2012 with principal diagnosis between codes CIE 9R MC 740-759. The source of information was the Basic Minimum Data Set. Socio-demographic and clinical variables were analyzed. RESULTS: One point six percent (1.6%) of the population was admitted to hospital due to rare congenital diseases. Fifty-eight point five percent (58.5%) were male, with average age 21.4 ± 21.5 years. The major diagnostic categories were: diseases of the nervous system (86.9%), circulatory systems diseases (51.7%) and musculoskeletal system diseases (50.3%). Eighteen percent (18%) of hospital admissions corresponded to patient readmissions. The service with the greatest number of episodes was Pediatric Surgery, 29%, followed by Neurosurgery, 20%. CONCLUSIONS: The pattern of rare congenital disease in the "Virgen de Nieves" University Hospital corresponds to a young patient, with a disease belonging to the diseases of the nervous system group of the major diagnostic categories, treated surgically, and with a low percentage of readmissions.
Subject(s)
Rare Diseases/congenital , Rare Diseases/epidemiology , Adolescent , Adult , Child , Cross-Sectional Studies , Female , Hospitalization , Hospitals, University , Humans , Infant , Infant, Newborn , Male , Retrospective Studies , Young AdultABSTRACT
Fundamento. Describir el patrón de pacientes ingresados por enfermedades raras correspondientes a anomalías congénitas en un hospital regional. Métodos. Estudio transversal retrospectivo. Se consideraron las altas de hospitalización de los años 2009-2012 con diagnóstico principal entre los códigos CIE 9RMC 740-759. La fuente de información fue el Conjunto Mínimo Básico de Datos. Se analizaron variables sociodemográficas y clínicas. Resultados. Ingresan en el hospital por enfermedades raras congénitas un 1,6% de la población Un 58,5% fueron varones, con edad media de 21,4 ± 21,5 años. Las Categorías Diagnósticas Mayores más frecuentes fueron Enfermedades del sistema nervioso (86,9%), Enfermedades del aparato circulatorio (51,7%) y Sistema músculo-esquelético (50,3%). El 18% de las hospitalizaciones correspondieron a reingresos de pacientes. El servicio con mayor número de episodios fue Cirugía Pediátrica, 29%, seguido de Neurocirugía, 20%. Conclusiones. El patrón de enfermedad rara congénita en el hospital Universitario Virgen de las Nieves corresponde a un paciente joven, con una enfermedad perteneciente al grupo de la Categoría Diagnóstica Mayor Enfermedad del sistema nervioso tratada quirúrgicamente y un porcentaje de reingresos no elevado (AU)
Background. To describe the pattern of patients admitted due to rare diseases corresponding to congenital anomalies in a regional hospital. Methods. Retrospective transversal study. We considered hospital discharges for the years 2009-2012 with principal diagnosis between codes CIE 9R MC 740-759.The source of information was the Basic Minimum Data Set. Socio-demographic and clinical variables were analyzed. Results. One point six percent (1.6%) of the population was admitted to hospital due to rare congenital diseases. Fifty-eight point five percent (58.5%) were male, with average age 21.4 ± 21.5 years. The major diagnostic categories were: diseases of the nervous system (86.9%), circulatory systems diseases (51.7%) and musculoskeletal system diseases (50.3%). Eighteen percent (18%) of hospital admissions corresponded to patient readmissions. The service with the greatest number of episodes was Pediatric Surgery, 29%, followed by Neurosurgery, 20%. Conclusions. The pattern of rare congenital disease in the Virgen de Nieves University Hospital corresponds to a young patient, with a disease belonging to the diseases of the nervous system group of the major diagnostic categories, treated surgically, and with a low percentage of readmissions (AU)
Subject(s)
Humans , Male , Female , Infant, Newborn , Rare Diseases/epidemiology , Congenital Abnormalities/epidemiology , Rare Diseases/congenital , Morbidity , Retrospective StudiesABSTRACT
OBJECTIVES: a) To determine the significance of stress-induced alterations in intestinal permeability by measuring the transmucosal flux of formyl-methionyl-leucyl-phenylalanine (f-MLP), a ubiquitous neutrophilic chemoattractant present in the human and rodent colon; and b) to determine whether stress and/or diet influence(s) bacterial adherence-induced changes in epithelial permeability by affecting the production of secretory immunoglobulin A (IgA), the main immune mechanism preventing bacterial adherence. DESIGN: Prospective, randomized, controlled study. SETTING: University animal research laboratory. SUBJECTS: Female Fischer rats. INTERVENTIONS: Rats were randomly assigned to four groups of seven animals each. Groups of animals were assigned to receive saline or dexamethasone (0.8 mg/kg ip) and were either starved (5% dextrose in water ad libitum) or fed (water and rat chow) for 48 hrs. MEASUREMENTS AND MAIN RESULTS: Mucosal barrier function was evaluated by measuring secretory IgA, bacterial adherence to the intestinal mucosa, and transepithelial electrical resistance, a measure of tight junction permeability. The f-MLP permeation across the mucosa was also determined in segments with significant permeability changes. Results indicate that starvation in dexamethasone-treated rats significantly impairs secretory IgA, promotes bacterial adherence to the mucosa, and results in increased intestinal permeability to f-MLP. These effects are significantly attenuated by the feeding of rat chow. CONCLUSIONS: Alterations in intestinal barrier function are characterized by depressed IgA, bacterial adherence to the intestinal mucosa, and permeation of clinically relevant proinflammatory luminal macromolecules (f-MLP). Enteral stimulation with foodstuffs is a necessary protective measure to prevent altered epithelial barrier function during glucocorticoid stress.
Subject(s)
Dexamethasone/pharmacology , Diet , Glucocorticoids/pharmacology , Intestine, Large/physiology , Stress, Physiological/physiopathology , Animals , Bacterial Adhesion/physiology , Cell Membrane Permeability/physiology , Chemotactic Factors/pharmacokinetics , Epithelium/physiology , Female , Immunoglobulin A, Secretory/analysis , Intestinal Mucosa/physiology , N-Formylmethionine Leucyl-Phenylalanine/pharmacokinetics , Prospective Studies , Random Allocation , Rats , Starvation/physiopathologyABSTRACT
Se presenta un caso de displacia camptomélica con múltiples anomalías congénitas, caracterizada por retraso en crecimiento, labio leporino, paladar hendido, tórax pequeño; con incurvación de extremidades inferiores acompañado de otras anomalías. Displacia, Displacia captomélica, anomalías congénitas
Subject(s)
Humans , Male , Infant, Newborn , Dwarfism , Abnormalities, MultipleABSTRACT
BACKGROUND/AIMS: Previous studies have shown that dexamethasone administration to rats results in diminution of biliary secretory immunoglobulin A concentration and alters intestinal barrier function to bacteria. The aims of this study were to examine and characterize the effect of dexamethasone on intestinal permeability and to determine the possible influence of bacterial adherence to the mucosa in this process. METHODS: Groups of adult Fisher rats were studied, and the effects of dexamethasone administration and bowel decontamination on bacterial adherence and intestinal permeability were determined in various bowel segments. RESULTS: Dexamethasone administration was associated with a significant increase in bacterial adherence to the mucosa, which was most pronounced in the cecum (4.33 +/- 0.2 colony forming units (cfu) (log10) per gram of mucosa for control vs. 6.23 +/- 0.2 for dexamethasone). This was accompanied by significant alterations in intestinal permeability as measured by a decrease in transepithelial electrical resistance (49.5 +/- 4.1 omega.cm2 for control vs. 25.4 +/- 2.5 omega.cm2 for dexamethasone). Dual sodium-mannitol flux analysis showed this defect to be predominantly paracellular. Antibiotic decontamination of the intestine completely abrogated the intestinal permeability defect observed in this model. CONCLUSIONS: Bacterial-mucosal cell interactions may be responsible for alterations in intestinal permeability after dexamethasone administration.
Subject(s)
Bacterial Adhesion/physiology , Dexamethasone/pharmacology , Intestinal Mucosa/metabolism , Animals , Bacterial Adhesion/drug effects , Ciprofloxacin/pharmacology , Electric Conductivity , Female , Intestinal Mucosa/drug effects , Intestinal Mucosa/physiology , Permeability , Rats , Rats, Inbred F344ABSTRACT
We describe a 19 years old patient with total situs inversus in association with Lutembacher's syndrome, and surgical intervention. Our review of the literature, did not disclosed any similar case.
