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1.
Int J Mol Sci ; 24(5)2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36902261

RESUMEN

Oxytocin is a peptide neurophysin hormone made up of nine amino acids and is used in induction of one in four births worldwide (more than 13 percent in the United States). Herein, we have developed an antibody alternative aptamer-based electrochemical assay for real-time and point-of-care detection of oxytocin in non-invasive saliva samples. This assay approach is rapid, highly sensitive, specific, and cost-effective. Our aptamer-based electrochemical assay can detect as little as 1 pg/mL of oxytocin in less than 2 min in commercially available pooled saliva samples. Additionally, we did not observe any false positive or false negative signals. This electrochemical assay has the potential to be utilized as a point-of-care monitor for rapid and real-time oxytocin detection in various biological samples such as saliva, blood, and hair extracts.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Electroquímicas , Oxitocina , Saliva , Humanos , Oxitocina/análisis , Saliva/química , Sistemas de Atención de Punto
2.
Biosens Bioelectron ; 222: 114986, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36508932

RESUMEN

Fungal infections are a rapidly increasing public health problem due to their high morbidity and mortality rates, especially in populations with compromised immune systems. Rapid and accurate diagnosis of these diseases is, therefore, necessary to improve the prognosis of afflicted patients. Unfortunately, current clinical chemistry practice relies on lengthy culturing methods that are insufficient to meet the fast turnaround requirements. Here we present a cost-effective and robust nucleic acid sensor that can identify the presence of histoplasmosis causing fungal genes, in whole blood or bronchoalveolar lavage (BAL) samples, far earlier than current methods. Our novel assay involves the hybridization of target gene sequences with immobilized nucleic acid probes, allowing direct, label-free detection of Hcp100, CBP1, and M antigen genes through electrochemical analysis. The resultant current is attributed to the presence of fungal targets in the sample solution. The assay provides ultra-sensitive detection of DNA molecules with a limit of detection (LOD) values down to 100 aM, sufficient to meet the clinical diagnostic need. In addition, the turnaround time for the sample to result is less than 90 min compared to the current clinical procedure's turnaround time of 3-4 weeks.


Asunto(s)
Técnicas Biosensibles , Humanos , Técnicas Biosensibles/métodos , ADN/análisis , Hibridación de Ácido Nucleico/métodos , Límite de Detección , Genes Fúngicos , Técnicas Electroquímicas/métodos
3.
ACS Nano ; 16(3): 3704-3714, 2022 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-35201755

RESUMEN

By monitoring opioid metabolites, wastewater-based epidemiology (WBE) could be an excellent tool for real-time information on the consumption of illicit drugs. A key limitation of WBE is the reliance on costly laboratory-based techniques that require substantial infrastructure and trained personnel, resulting in long turnaround times. Here, we present an aptamer-based graphene field effect transistor (AptG-FET) platform for simultaneous detection of three different opioid metabolites. This platform provides a reliable, rapid, and inexpensive method for quantitative analysis of opioid metabolites in wastewater. The platform delivers a limit of detection 2-3 orders of magnitude lower than previous reports, but in line with the concentration range (pg/mL to ng/mL) of these opioid metabolites present in real samples. To enable multianalyte detection, we developed a facile, reproducible, and high-yield fabrication process producing 20 G-FETs with integrated side gate platinum (Pt) electrodes on a single chip. Our devices achieved the selective multianalyte detection of three different metabolites: noroxycodone (NX), 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), and norfentanyl (NF) in wastewater diluted 20× in buffer.


Asunto(s)
Grafito , Drogas Ilícitas , Analgésicos Opioides , Electrodos , Drogas Ilícitas/análisis , Aguas Residuales/análisis , Aguas Residuales/química
4.
Am J Respir Crit Care Med ; 204(8): 921-932, 2021 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-34409924

RESUMEN

Rationale: Current guidelines recommend patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia receive empirical antibiotics for suspected bacterial superinfection on the basis of weak evidence. Rates of ventilator-associated pneumonia (VAP) in clinical trials of patients with SARS-CoV-2 pneumonia are unexpectedly low. Objectives: We conducted an observational single-center study to determine the prevalence and etiology of bacterial superinfection at the time of initial intubation and the incidence and etiology of subsequent bacterial VAP in patients with severe SARS-CoV-2 pneumonia. Methods: Bronchoscopic BAL fluid samples from all patients with SARS-CoV-2 pneumonia requiring mechanical ventilation were analyzed using quantitative cultures and a multiplex PCR panel. Actual antibiotic use was compared with guideline-recommended therapy. Measurements and Main Results: We analyzed 386 BAL samples from 179 patients with SARS-CoV-2 pneumonia requiring mechanical ventilation. Bacterial superinfection within 48 hours of intubation was detected in 21% of patients. Seventy-two patients (44.4%) developed at least one VAP episode (VAP incidence rate = 45.2/1,000 ventilator days); 15 (20.8%) initial VAPs were caused by difficult-to-treat pathogens. The clinical criteria did not distinguish between patients with or without bacterial superinfection. BAL-based management was associated with significantly reduced antibiotic use compared with guideline recommendations. Conclusions: In patients with SARS-CoV-2 pneumonia requiring mechanical ventilation, bacterial superinfection at the time of intubation occurs in <25% of patients. Guideline-based empirical antibiotic management at the time of intubation results in antibiotic overuse. Bacterial VAP developed in 44% of patients and could not be accurately identified in the absence of microbiologic analysis of BAL fluid.

5.
Crit Care Explor ; 3(5): e0415, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-34079946

RESUMEN

OBJECTIVES: Determine the variation in outcomes and respiratory mechanics between the subjects who are intubated earlier versus later in their coronavirus disease 2019 course. DESIGN: Retrospective cohort study. SETTING: Northwestern Memorial Hospital ICUs. PATIENTS: All patients intubated for coronavirus disease 2019 between March 2020 and June 2020. INTERVENTIONS: Patients were stratified by time to intubation: 30 subjects were intubated 4-24 hours after presentation and 24 subjects were intubated 5-10 days after presentation. Baseline characteristics, hospitalization, ventilator mechanics, and outcomes were extracted and analyzed. Ten clinically available CT scans were manually reviewed to identify evidence of pulmonary vascular thrombosis and intussusceptive angiogenesis. MEASUREMENTS AND MAIN RESULTS: Median time from symptom onset to intubation was significantly different between the early and late intubation cohorts, with the latter being intubated later in the course of their illness (7.9 vs 11.8 d; p = 0.04). The early intubation cohort had a lower mortality rate than the late intubation cohort (6% vs 30%, p < 0.001) without significantly different respiratory mechanics at the time of intubation. The late intubation cohort was noted to have higher dead space ratio (0.40 vs 0.52; p = 0.03). On review of CT scans, the late intubation cohort also had more dilated peripheral segments on imaging (two segments vs five segments). CONCLUSIONS: The question as to whether delaying intubation is beneficial or harmful for patients with coronavirus disease 2019-induced hypoxemic respiratory failure has yet to be answered. As our approaches to coronavirus disease 2019 continue to evolve, the decision of timing of intubation remains paramount. Although noninvasive ventilation may allow for delaying intubation, it is possible that there are downstream effects of delayed intubation that should be considered, including the potential for pulmonary vascular thrombosis and intussusceptive angiogenesis with delayed intubation.

6.
medRxiv ; 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33469593

RESUMEN

BACKGROUND: Severe community-acquired pneumonia secondary to SARS-CoV-2 is a leading cause of death. Current guidelines recommend patients with SARS-CoV-2 pneumonia receive empirical antibiotic therapy for suspected bacterial superinfection, but little evidence supports these recommendations. METHODS: We obtained bronchoscopic bronchoalveolar lavage (BAL) samples from patients with SARS-CoV-2 pneumonia requiring mechanical ventilation. We analyzed BAL samples with multiplex PCR and quantitative culture to determine the prevalence of superinfecting pathogens at the time of intubation and identify episodes of ventilator-associated pneumonia (VAP) over the course of mechanical ventilation. We compared antibiotic use with guideline-recommended care. RESULTS: The 179 ventilated patients with severe SARS-CoV-2 pneumonia discharged from our hospital by June 30, 2020 were analyzed. 162 (90.5%) patients had at least one BAL procedure; 133 (74.3%) within 48 hours after intubation and 112 (62.6%) had at least one subsequent BAL during their hospitalization. A superinfecting pathogen was identified within 48 hours of intubation in 28/133 (21%) patients, most commonly methicillin-sensitive Staphylococcus aureus or Streptococcus species (21/28, 75%). BAL-based treatment reduced antibiotic use compared with guideline-recommended care. 72 patients (44.4%) developed at least one VAP episode. Only 15/72 (20.8%) of initial VAPs were attributable to multidrug-resistant pathogens. The incidence rate of VAP was 45.2/1000 ventilator days. CONCLUSIONS: With use of sensitive diagnostic tools, bacterial superinfection at the time of intubation is infrequent in patients with severe SARS-CoV-2 pneumonia. Treatment based on current guidelines would result in substantial antibiotic overuse. The incidence rate of VAP in ventilated patients with SARS-CoV-2 pneumonia are higher than historically reported.

7.
Preprint en Inglés | medRxiv | ID: ppmedrxiv-20248588

RESUMEN

BackgroundSevere community-acquired pneumonia secondary to SARS-CoV-2 is a leading cause of death. Current guidelines recommend patients with SARS-CoV-2 pneumonia receive empirical antibiotic therapy for suspected bacterial superinfection, but little evidence supports these recommendations. MethodsWe obtained bronchoscopic bronchoalveolar lavage (BAL) samples from patients with SARS-CoV-2 pneumonia requiring mechanical ventilation. We analyzed BAL samples with multiplex PCR and quantitative culture to determine the prevalence of superinfecting pathogens at the time of intubation and identify episodes of ventilator-associated pneumonia (VAP) over the course of mechanical ventilation. We compared antibiotic use with guideline-recommended care. ResultsThe 179 ventilated patients with severe SARS-CoV-2 pneumonia discharged from our hospital by June 30, 2020 were analyzed. 162 (90.5%) patients had at least one BAL procedure; 133 (74.3%) within 48 hours after intubation and 112 (62.6%) had at least one subsequent BAL during their hospitalization. A superinfecting pathogen was identified within 48 hours of intubation in 28/133 (21%) patients, most commonly methicillin-sensitive Staphylococcus aureus or Streptococcus species (21/28, 75%). BAL-based treatment reduced antibiotic use compared with guideline-recommended care. 72 patients (44.4%) developed at least one VAP episode. Only 15/72 (20.8%) of initial VAPs were attributable to multidrug-resistant pathogens. The incidence rate of VAP was 45.2/1000 ventilator days. ConclusionsWith use of sensitive diagnostic tools, bacterial superinfection at the time of intubation is infrequent in patients with severe SARS-CoV-2 pneumonia. Treatment based on current guidelines would result in substantial antibiotic overuse. The incidence rate of VAP in ventilated patients with SARS-CoV-2 pneumonia are higher than historically reported.

8.
Ophthalmic Surg Lasers Imaging Retina ; 51(5): S17-S25, 2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-32484897

RESUMEN

BACKGROUND AND OBJECTIVE: To determine the prevalence of retinal disease among a population in Mwanza, Tanzania, and to identify relevant risk factors for retinal disorders in this cohort. PATIENTS AND METHODS: A cross-sectional population-based study was conducted in Mwanza, Tanzania, among patients older than 18 years. Participants completed a demographics survey and underwent an ophthalmic examination that included fundus photography. RESULTS: Complete data were available for 1,007 (93.8%) of the 1,073 persons examined. The prevalence of vitreoretinal disorders was 22.8% (230/1,007). The leading retinal diseases were age-related macular degeneration (7.0%), hypertensive retinopathy (4.5%), and macular scars (2.7%). CONCLUSION: This study is the first population-based study of retinal disease in Mwanza. The findings reveal a considerable burden of retinal disease in this region, suggesting a need for trained local ophthalmic personnel and resources. [Ophthalmic Surg Lasers Imaging Retina. 2020;51:S17-S25.].


Asunto(s)
Población Negra , Vigilancia de la Población/métodos , Enfermedades de la Retina/etnología , Medición de Riesgo/métodos , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Tanzanía/epidemiología
9.
J Cataract Refract Surg ; 45(2): 181-187, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30471846

RESUMEN

PURPOSE: To examine the long-term effect of femtosecond laser-assisted cataract surgery on intraocular pressure (IOP) in healthy (control) and glaucomatous eyes. SETTING: University of Colorado, Aurora, Colorado, and Vanderbilt University, Nashville, Tennessee, USA. DESIGN: Retrospective case series. METHODS: The study comprised patients aged 18 to 89 years meeting the inclusion criteria. Combination procedures were excluded. The main outcome measure was the change in the mean IOP from baseline to postoperatively. RESULTS: Of the 504 eyes meeting the criteria, 278 were in the glaucoma/glaucoma suspect group and 226 in the control group. Both groups had an initial mean increase in IOP 1 day postoperatively (control: +2.0 mm Hg; 95% confidence interval [CI], 1.4-2.6; glaucoma/glaucoma suspect: +3.4 mm Hg; 95% CI, 2.5-4.2) (both P < .001). The increase was significantly higher in the glaucoma/glaucoma suspect group. The IOP returned to baseline levels at 1 week. At 1 month, both groups had a significant decrease in IOP that persisted until year 1 in the control group and through 3 years in the glaucoma group. The number of IOP medications was unchanged in the glaucoma group during follow-up. The glaucoma/glaucoma suspect group achieved significantly greater IOP lowering than the control group after 6 months. CONCLUSIONS: Control eyes and eyes with glaucoma had an initial mean IOP rise 1 day after femtosecond laser-assisted cataract surgery. This was followed by a significant decrease starting at 1 month. The reduction was sustained through 3 years in the glaucoma group.


Asunto(s)
Extracción de Catarata/métodos , Catarata/complicaciones , Glaucoma de Ángulo Abierto/fisiopatología , Presión Intraocular/fisiología , Terapia por Láser/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Catarata/fisiopatología , Femenino , Estudios de Seguimiento , Glaucoma de Ángulo Abierto/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento , Agudeza Visual , Adulto Joven
10.
Plant Signal Behav ; 13(5): e1467689, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29944445

RESUMEN

Pattern recognition receptors (PRR) are plasma membrane (PM) proteins that recognize microbe-associated molecular patterns (MAMPs), triggering an immune response. PRR are classified as receptor like kinases (RLKs) or receptor like proteins (RLPs). The PM localization of PRRs, which is crucial for their availability to sense MAMPs, depends on their appropriate trafficking through the endomembrane system. Recently, we have identified SlPRA1A, a prenylated RAB acceptor type-1 (PRA1) from S. lycopersicum, as a regulator of RLP-PRR localization and protein levels. SlPRA1A overexpression strongly decreases RLP-PRR protein levels, particularly those of LeEIX2, redirecting it to the vacuole for degradation. Interestingly, SlPRA1A does not affect RLK-PRRs, indicating its activity to be specific to RLP-PRR systems. As PRA1 proteins stabilize RABs on membranes, promoting RABs activity, we aimed to identify a RAB target of SlPRA1A. Screening of a set of A. thaliana RABs revealed that AtRABA1e is able to mimic SlPRA1A activity. Through live cell imaging, we observed that SlPRA1A enhances AtRABA1e localization on SlPRA1A positive punctuated structures. These results indicate that AtRABA1e is a putative target of SlPRA1, and a co-regulator of LeEIX2 trafficking and degradation.


Asunto(s)
Transporte Biológico/fisiología , Inmunidad de la Planta/fisiología , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Inmunidad de la Planta/genética , Proteínas de Plantas/genética
11.
Cornea ; 37(7): 912-915, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29324584

RESUMEN

PURPOSE: We report our experience with the use of maternally derived serum eye drops as adjunctive treatment in the management of pediatric persistent corneal epithelial defects. METHODS: Five eyes of 4 patients were identified in a retrospective review of pediatric patients with persistent corneal epithelial defects who received maternal serum drops. Diagnoses associated with the defects comprised pontine tegmental cap dysplasia with bilateral cranial nerve V1, V2, V3, and VII palsies; pontine tegmental cap dysplasia with left cranial nerve V1, VII, and VIII palsies; traumatic left cranial nerve II, V1, V2, and VI palsies due to a basilar skull fracture; and Stevens-Johnson syndrome with ocular involvement. We evaluated the feasibility of using maternally derived serum drops; thus, we looked at the ability to prepare and tolerate the drops as well as any complications that could have been associated with treatment. Other data collected included visual acuity, corneal examination, and current and previous treatments. RESULTS: Both the duration of therapy and time of follow-up ranged from 5 to 28 months. All patients experienced improvement or resolution of their corneal epithelial defects within 3 weeks of initiating serum eye drops. Furthermore, there were no adverse effects from the use of allogeneic serum drops. CONCLUSIONS: Maternal serum eye drops are a well-tolerated and potentially beneficial addition to the management of pediatric persistent corneal epithelial defects.


Asunto(s)
Enfermedades de la Córnea/tratamiento farmacológico , Epitelio Corneal/patología , Soluciones Oftálmicas/uso terapéutico , Suero , Niño , Preescolar , Enfermedades de los Nervios Craneales/complicaciones , Epitelio Corneal/efectos de los fármacos , Femenino , Humanos , Lactante , Masculino , Madres , Estudios Retrospectivos , Síndrome de Stevens-Johnson/complicaciones
12.
J Safety Res ; 60: 29-34, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28160810

RESUMEN

INTRODUCTION: Many non-battle injuries among deployed soldiers are due to occupational-related tasks. Given that non-battle injuries are a significant cause of morbidity and mortality, occupational safety and health are of great concern to the military. Some of the leading causes of non-battle injuries in the military are also common in non-military occupational settings. Nationally, falls and motor-vehicle accidents are leading causes of non-fatal occupational injuries in the civilian workforce. The objective of this research is to identify the leading causes, types, and anatomic locations of non-fatal non-battle injuries in Afghanistan and Iraq. METHODS: Non-battle injuries were identified from medical air evacuation records. Causes of air evacuated injuries were identified and coded using the diagnosis and narrative patient history in the air evacuation records. Descriptive statistics were used to report the air evacuated non-battle injury rates, causes, injury types, and anatomic locations. RESULTS: Between 2001 and 2013, there were 68,349 medical air evacuations from Afghanistan and Iraq. Non-battle injuries accounted for 31% of air evacuations from Afghanistan and 34% from Iraq. These injuries were the leading diagnosis category for air evacuations. The three leading causes of injury for Afghanistan and Iraq, respectively, were sports/physical training (23% and 24%), falls/jumps (19% and 16%), and military vehicle-related accidents (8% and 11%). The leading injury types were fractures (21%), overuse pain and inflammation (16%), and dislocations (11%). PRACTICAL APPLICATIONS: Given that over 30% of medical evacuations of soldiers result from non-battle injuries, prevention of such conditions would substantially enhance military readiness during combat.


Asunto(s)
Accidentes/estadística & datos numéricos , Personal Militar/estadística & datos numéricos , Heridas y Lesiones/epidemiología , Campaña Afgana 2001- , Afganistán/epidemiología , Irak/epidemiología , Guerra de Irak 2003-2011 , Estados Unidos , Heridas y Lesiones/clasificación , Heridas y Lesiones/etiología
13.
Radiology ; 273(1): 78-87, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25025582

RESUMEN

PURPOSE: To analyze imaging utilization and emergency radiology process turnaround times in response to the April 15, 2013, Boston Marathon bombing in order to identify opportunities for improvement in the Brigham and Women's Hospital (BWH) emergency operations plan. MATERIALS AND METHODS: Institutional review board approval was obtained with waivers of informed consent. Patient demographics, injuries, and outcomes were gathered, along with measures of emergency department (ED) imaging utilization and turnaround times, which were compared with operations from the preceding year by using the Wilcoxon rank sum test. Multivariate linear regression was used to assess contributors to examination cancellations. RESULTS: Forty patients presented to BWH after the bombing; 16 were admitted and 24 were discharged home. There were no fatalities. Ten patients required emergent surgery. Blast injury types included 13 (33%) primary, 20 (51%) secondary, three (8%) tertiary, and 19 (49%) quaternary. Thirty-one patients (78%) underwent imaging in the ED; 57 radiographic examinations in 30 patients and 16 computed tomographic (CT) examinations in seven patients. Sixty-two radiographic and 14 CT orders were cancelled. Median time from blast to patient arrival was 97 minutes (interquartile range [IQR], 43-139 minutes), patient arrival to ED examination order, 24 minutes (IQR, 12-50 minutes), order to examination completion, 49 minutes (IQR, 26-70 minutes), and examination completion to available dictated text report, 75 minutes (IQR, 19-147 minutes). Examination completion turnaround times were significantly increased for radiography (52 minutes [IQR, 26-73 minutes] vs annual median, 31 minutes [IQR, 19-48 minutes]; P = .001) and decreased for CT (37 minutes [IQR, 26-50 minutes] vs annual median, 72 minutes [IQR, 40-129 minutes]; P = .001). There were no significant differences in report availability turnaround time (75 minutes [IQR, 19-147 minutes] vs annual median, 74 minutes [IQR, 35-127 minutes]; P = .34). CONCLUSION: The surge in imaging utilization after the Boston Marathon bombing stressed emergency radiology operations. Process analysis enabled identification of successes and opportunities for improvement in ongoing emergency operations planning. © RSNA, 2014.


Asunto(s)
Traumatismos por Explosión/diagnóstico , Diagnóstico por Imagen , Servicio de Urgencia en Hospital/organización & administración , Traumatismo Múltiple/diagnóstico , Grupo de Atención al Paciente/organización & administración , Terrorismo , Adulto , Anciano , Traumatismos por Explosión/cirugía , Bombas (Dispositivos Explosivos) , Boston , Planificación en Desastres , Medicina de Emergencia , Femenino , Humanos , Masculino , Incidentes con Víctimas en Masa , Traumatismo Múltiple/cirugía , Estudios de Casos Organizacionales
14.
Neuroimage Clin ; 2: 402-13, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24179794

RESUMEN

Magnetic resonance imaging (MRI) can be used to detect lesions in the brains of multiple sclerosis (MS) patients and is essential for diagnosing the disease and monitoring its progression. In practice, lesion load is often quantified by either manual or semi-automated segmentation of MRI, which is time-consuming, costly, and associated with large inter- and intra-observer variability. We propose OASIS is Automated Statistical Inference for Segmentation (OASIS), an automated statistical method for segmenting MS lesions in MRI studies. We use logistic regression models incorporating multiple MRI modalities to estimate voxel-level probabilities of lesion presence. Intensity-normalized T1-weighted, T2-weighted, fluid-attenuated inversion recovery and proton density volumes from 131 MRI studies (98 MS subjects, 33 healthy subjects) with manual lesion segmentations were used to train and validate our model. Within this set, OASIS detected lesions with a partial area under the receiver operating characteristic curve for clinically relevant false positive rates of 1% and below of 0.59% (95% CI; [0.50%, 0.67%]) at the voxel level. An experienced MS neuroradiologist compared these segmentations to those produced by LesionTOADS, an image segmentation software that provides segmentation of both lesions and normal brain structures. For lesions, OASIS out-performed LesionTOADS in 74% (95% CI: [65%, 82%]) of cases for the 98 MS subjects. To further validate the method, we applied OASIS to 169 MRI studies acquired at a separate center. The neuroradiologist again compared the OASIS segmentations to those from LesionTOADS. For lesions, OASIS ranked higher than LesionTOADS in 77% (95% CI: [71%, 83%]) of cases. For a randomly selected subset of 50 of these studies, one additional radiologist and one neurologist also scored the images. Within this set, the neuroradiologist ranked OASIS higher than LesionTOADS in 76% (95% CI: [64%, 88%]) of cases, the neurologist 66% (95% CI: [52%, 78%]) and the radiologist 52% (95% CI: [38%, 66%]). OASIS obtains the estimated probability for each voxel to be part of a lesion by weighting each imaging modality with coefficient weights. These coefficients are explicit, obtained using standard model fitting techniques, and can be reused in other imaging studies. This fully automated method allows sensitive and specific detection of lesion presence and may be rapidly applied to large collections of images.

15.
Am J Hematol ; 88(10): 874-82, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23813900

RESUMEN

The risk of graft-rejection after allogeneic hematopoietic cell transplantation using conventional cyclophosphamide-based conditioning is increased in patients with bone marrow failure syndromes (BMFS) who are heavily transfused and often HLA-alloimmunized. Fifty-six patients with BMFS underwent fludarabine-based reduced-intensity conditioning and allogeneic peripheral blood progenitor cell (PBPC) transplantation at a single institution. The conditioning regimen consisted of intravenous cyclophosphamide, fludarabine, and equine antithymocyte globulin. Graft-versus-host disease (GVHD) prophylaxis included cyclosporine A alone or in combination with either mycophenolate mofetil or methotrexate. To reduce the risk of graft-rejection/failure, unmanipulated G-CSF mobilized PBPCs obtained from an HLA-identical or single HLA-antigen mismatched relative were transplanted rather than donor bone marrow. Despite a high prevalence of pretransplant HLA-alloimmunization (41%) and a heavy prior transfusion burden, graft-failure did not occur with all patients having sustained donor lympho-hematopoietic engraftment. The cumulative incidence of grade II-IV acute-GVHD and chronic-GVHD was 51.8% and 72%, respectively; with 87.1% surviving at a median follow-up of 4.5 years. A multivariate analysis showed pretransplant alloimmunization and rapid donor T-cell engraftment (≥95% donor by day 30) were both significantly (P < 0.05) associated with the development of chronic-GVHD (adjusted HR 2.13 and 2.99, respectively). These data show fludarabine-based PBPC transplantation overcomes the risk of graft-failure in patients with BMFS, although rapid donor T-cell engraftment associated with this approach appears to increase the risk of chronic-GVHD. (Clinicaltrials.gov identifier: NCT00003838).


Asunto(s)
Rechazo de Injerto/prevención & control , Enfermedad Injerto contra Huésped/prevención & control , Hemoglobinuria Paroxística/terapia , Trasplante de Células Madre de Sangre Periférica , Linfocitos T , Acondicionamiento Pretrasplante , Adulto , Anciano , Anemia Aplásica , Suero Antilinfocítico/administración & dosificación , Antineoplásicos/administración & dosificación , Enfermedades de la Médula Ósea , Trastornos de Fallo de la Médula Ósea , Niño , Enfermedad Crónica , Ciclosporina/administración & dosificación , Femenino , Rechazo de Injerto/etiología , Rechazo de Injerto/patología , Enfermedad Injerto contra Huésped/etiología , Enfermedad Injerto contra Huésped/patología , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Hemoglobinuria Paroxística/patología , Humanos , Inmunosupresores/administración & dosificación , Masculino , Persona de Mediana Edad , Ácido Micofenólico/administración & dosificación , Ácido Micofenólico/análogos & derivados , Factores de Riesgo , Terapia Recuperativa , Factores de Tiempo , Trasplante Homólogo , Vidarabina/administración & dosificación , Vidarabina/análogos & derivados , Adulto Joven
16.
Anal Chim Acta ; 773: 45-51, 2013 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-23561905

RESUMEN

A series of Boron-Doped Diamond (BDD) ultramicroelectrode arrays were fabricated and investigated for their performance as electrochemical sensors to detect trace level metals such as cadmium. The steady-state diffusion behavior of these sensors was validated using cyclic voltammetry followed by electrochemical detection of cadmium in water and in human urine to demonstrate high sensitivity (>200 µA ppb(-1) cm(-2)) and low background current (<4 nA). When an array of ultramicroelectrodes was positioned with optimal spacing, these BDD sensors showed a sigmoidal diffusion behavior. They also demonstrated high accuracy with linear dose dependence for quantification of cadmium in a certified reference river water sample from the U.S. National Institute of Standards and Technology (NIST) as well as in a human urine sample spiked with 0.25-1 ppb cadmium.


Asunto(s)
Cadmio/orina , Espectrometría de Fluorescencia , Cadmio/normas , Calibración , Exposición a Riesgos Ambientales , Iones/química , Análisis de los Mínimos Cuadrados , Oxidación-Reducción , Plásticos/química , Análisis de Componente Principal , Suelo/química , Espectrometría de Fluorescencia/normas , Rayos X
18.
Bioorg Med Chem ; 14(16): 5467-80, 2006 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-16713270

RESUMEN

The discovery of new non-nucleoside antiviral compounds is of significant and growing interest for treating herpes virus infections due to the emergence of nucleoside-resistant strains. Using a whole cell virus-induced cytopathogenic assay, we tested a series of substituted triaryl heterocyclic compounds including acridones, xanthones, and acridines. The compounds which showed activity against Herpes Simplex-1 and/or Herpes Simplex-2 were further assayed for inhibition of topoisomerase activity to gain insight into the mechanism of action. The results indicate that the acridine analogs bearing substituted carboxamides and bulky 9-amino functionalities are able to inhibit herpes infections as well as inhibit topoisomerase II relaxation of supercoiled DNA. Given the mechanism of action of amsacrine (a closely related, well-studied 9-amino substituted acridine), the compounds were further tested in a DNA topoisomerase II cleavage assay to determine if the compounds function as poisons. The results show that the acridines synthesized in this study function through a different mechanism to that of amsacrine, most likely by blocking topoisomerase binding to DNA (akin to that of aclarubicin). This not only suggests a unique mechanism of action in treating herpes virus infections, but also may be of great interest in the development of anticancer agents that target topoisomerase II activity.


Asunto(s)
Acridinas/farmacología , Antivirales/farmacología , Herpesvirus Humano 1/efectos de los fármacos , Herpesvirus Humano 2/efectos de los fármacos , Inhibidores de Topoisomerasa , Replicación Viral/efectos de los fármacos , Acridinas/síntesis química , Acridonas , Antivirales/síntesis química , ADN-Topoisomerasas/metabolismo , ADN-Topoisomerasas de Tipo II/metabolismo , Herpesvirus Humano 1/enzimología , Herpesvirus Humano 2/enzimología , Pruebas de Sensibilidad Microbiana , Inhibidores de Topoisomerasa II
19.
Isr Med Assoc J ; 5(3): 230, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12725153
20.
Cell Death Differ ; 9(7): 726-33, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12058273

RESUMEN

The morphological features of programmed cell death (PCD) and the molecular machinery involved in the death program in animal cells have been intensively studied. In plants, cell death has been widely observed in predictable patterns throughout differentiation processes and in defense responses. Several lines of evidence argue that plant PCD shares some characteristic features with animal PCD. However, the molecular components of the plant PCD machinery remain obscure. We have shown that plant cells undergo PCD by constitutively expressed molecular machinery upon induction with the fungal elicitor EIX or by staurosporine in the presence of cycloheximide. The permeable peptide caspase inhibitors, zVAD-fmk and zBocD-fmk, blocked PCD induced by EIX or staurosporine. Using labeled VAD-fmk, active caspase-like proteases were detected within intact cells and in cell extracts of the PCD-induced cells. These findings suggest that caspase-like proteases are responsible for the execution of PCD in plant cells.


Asunto(s)
Apoptosis , Caspasas/metabolismo , Clorometilcetonas de Aminoácidos/farmacología , Bisbenzimidazol , Inhibidores de Caspasas , Extractos Celulares , Células Cultivadas , Medios de Cultivo , Inhibidores de Cisteína Proteinasa/farmacología , Citosol/metabolismo , Colorantes Fluorescentes , Coloración y Etiquetado/métodos , Estaurosporina/farmacología , Nicotiana/citología , Nicotiana/enzimología
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