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1.
Environ Sci Technol ; 58(16): 6954-6963, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38576415

RESUMO

Methane is both a significant and short-lived greenhouse gas compared to CO2, and reducing methane emissions from natural gas distribution systems may offer cost-effective reduction opportunities. We report substantial new direct leak rate measurements from customer meter set assemblies (MSAs) in Southern California. In a novel way, emission factors are defined in terms of aboveground Hazardous and Nonhazardous leak categories, which take direct advantage of readily available industry leak data. We also studied leaks that were not detected as part of normal leak survey procedures. As a result, this yields company-specific emission factors that can be used to track progress in reducing methane emissions. This approach also has the advantage of explicitly accounting for the skewed or fat-tail distribution of leak rates by treating high flow rate MSA leaks separately from low flow rate MSA leaks. The Southern California Gas (SoCalGas) methane emission factors, based on 485 leak rate measurements by direct enclosure, were 4.55 (95% confidence interval: 2.32 to 7.14) kg/day for Hazardous leaks, 0.149 (0.119 to 0.183) kg/day for Nonhazardous leaks, and 0.0039 (0.0003 to 0.0198) kg/day for Non-Detected leaks. The percentage of surveyed meters with nondetected leaks was 29.1% (24.3 to 34.6%). Based on a robust Monte Carlo analysis, total leak emissions from MSAs for the SoCalGas system were reduced by 35% based on data from 2015 to 2022. These reductions were attributed to surveying a larger number of MSAs and accelerated leak repair rates. In traditional population-based emission inventories, an individual emission factor for a given asset category is multiplied by the total population of MSAs within the category. This approach simply cannot capture the reduction in leak numbers and methane emissions resulting from leak mitigation and prevention programs.

3.
Sensors (Basel) ; 23(17)2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37687868

RESUMO

This contribution shows the possibilities of applying a low-cost, multi-purpose data logger built around an Arduino Mega 2560 single-board computer. Most projects use this kind of hardware to develop single-purpose data loggers. In this work, a data logger with a more general hardware and software architecture was built to perform measurement campaigns in very different domains. The wide applicability of this data logger was demonstrated with short-term monitoring campaigns in relation to outdoor air quality, human activity in an office, motion of a journey on a bike, and exhaust gas monitoring of a diesel generator. In addition, an assessment process and corresponding evaluation framework are proposed to assess the credibility of low-cost scientific devices built in-house. The experiences acquired during the development of the system and the short measurement campaigns were used as inputs in the assessment process. The assessment showed that the system scores positively on most product-related targets. However, unexpected events affect the assessment over the longer term. This makes the development of low-cost scientific devices harder than expected. To assure stability and long-term performance of this type of design, continuous evaluation and regular engineering corrections are needed throughout longer testing periods.

4.
Nat Commun ; 14(1): 4155, 2023 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-37438348

RESUMO

The small Ultra-Red Fluorescent Protein (smURFP) represents a new class of fluorescent protein with exceptional photostability and brightness derived from allophycocyanin in a previous directed evolution. Here, we report the smURFP crystal structure to better understand properties and enable further engineering of improved variants. We compare this structure to the structures of allophycocyanin and smURFP mutants to identify the structural origins of the molecular brightness. We then use a structure-guided approach to develop monomeric smURFP variants that fluoresce with phycocyanobilin but not biliverdin. Furthermore, we measure smURFP photophysical properties necessary for advanced imaging modalities, such as those relevant for two-photon, fluorescence lifetime, and single-molecule imaging. We observe that smURFP has the largest two-photon cross-section measured for a fluorescent protein, and that it produces more photons than organic dyes. Altogether, this study expands our understanding of the smURFP, which will inform future engineering toward optimal FPs compatible with whole organism studies.


Assuntos
Biliverdina , Corantes , Proteínas Luminescentes/genética , Engenharia , Proteína Vermelha Fluorescente
5.
PeerJ ; 11: e14806, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36945355

RESUMO

The gastrointestinal (GI) tract can be affected by different diseases or lesions such as esophagitis, ulcers, hemorrhoids, and polyps, among others. Some of them can be precursors of cancer such as polyps. Endoscopy is the standard procedure for the detection of these lesions. The main drawback of this procedure is that the diagnosis depends on the expertise of the doctor. This means that some important findings may be missed. In recent years, this problem has been addressed by deep learning (DL) techniques. Endoscopic studies use digital images. The most widely used DL technique for image processing is the convolutional neural network (CNN) due to its high accuracy for modeling complex phenomena. There are different CNNs that are characterized by their architecture. In this article, four architectures are compared: AlexNet, DenseNet-201, Inception-v3, and ResNet-101. To determine which architecture best classifies GI tract lesions, a set of metrics; accuracy, precision, sensitivity, specificity, F1-score, and area under the curve (AUC) were used. These architectures were trained and tested on the HyperKvasir dataset. From this dataset, a total of 6,792 images corresponding to 10 findings were used. A transfer learning approach and a data augmentation technique were applied. The best performing architecture was DenseNet-201, whose results were: 97.11% of accuracy, 96.3% sensitivity, 99.67% specificity, and 95% AUC.


Assuntos
Aprendizado Profundo , Redes Neurais de Computação , Trato Gastrointestinal/diagnóstico por imagem , Endoscopia Gastrointestinal , Diagnóstico por Computador/métodos
6.
Methods Mol Biol ; 2564: 75-97, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36107338

RESUMO

Directed evolution has revolutionized the way scientists create new biomolecules not found in nature. Error-prone polymerase chain reaction (PCR) introduces random mutations and was used to evolve jellyfish and coral fluorescent proteins in bacteria. We describe a novel method for the directed evolution of a far-red fluorescent protein in E. coli. The new method used genes to produce fluorophores inside E. coli and allowed changing the native fluorophore, phycocyanobilin, for a second small-molecule fluorophore, biliverdin. The directed evolution blueshifted the fluorescence, which enhanced the quantum yield to produce a brighter fluorescent protein. Finally, the evolution selected fluorescent proteins that expressed in large quantities in E. coli. The evolved fluorescent protein was named the small ultra-red fluorescent protein (smURFP) and was biophysically as bright as the enhanced green fluorescent protein (EGFP). This chapter describes the materials and methods used to evolve a far-red fluorescent protein in bacteria. While the focus is a fluorescent protein, the protocol is adaptable for the evolution of other biomolecules in bacteria when using a proper selection strategy.


Assuntos
Antozoários , Escherichia coli , Animais , Antozoários/genética , Antozoários/metabolismo , Biliverdina/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Fluorescência , Mutação
7.
J Craniovertebr Junction Spine ; 13(3): 339-343, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36263343

RESUMO

Background: Although there are studies that adequately document the linear correlation between pelvic incidence (PI), sacral slope, lumbar lordosis, and thoracic kyphosis, few have analyzed the pelvic-spine correlation including the cervical spine. Methods: This is a cross-sectional study, wherein the cervical spine was evaluated using radiography and computed tomography (CT) scans, the lumbosacral spine and the pelvis was evaluated using radiography, in adult patients without spinal pathology. Using the Surgimap tool, cervical and spinopelvic parameters were calculated by several investigators. To evaluate the correlation between cervical and spinopelvic parameters, Spearman's coefficient was calculated. To evaluate the concordance correlation of the measured parameters of cervical sagittal alignment on tomography and conventional radiography, Lin's coefficient was calculated and Bland-Altman plots were performed. Results: A total of 51 healthy adults were included in a follow-up from January 2019 to December 2020. Cervical sagittal alignment and sagittal spinopelvic alignment were assessed using radiography, and a correlation was observed between T1 slope (T1S) and lumbar mismatch (coefficient of 0.28, P = 0.047). Then, cervical sagittal alignment was evaluated using CT and sagittal spinopelvic alignment using radiography, and no correlation was observed between PI and thoracic inlet angle or cervical mismatch with lumbar mismatch. Conclusion: In asymptomatic patients, in whom cervical sagittal alignment and spinal-pelvic alignment were evaluated, only a positive correlation was found between lumbar mismatch and T1S, which lacks clinical significance. No concordance was identified between lumbar mismatch and cervical mismatch. Therefore, it is inferred that there is an independence between the sagittal spine-pelvic alignment with respect to the sagittal cervical alignment.

8.
Transl Vis Sci Technol ; 11(8): 23, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35998058

RESUMO

Purpose: The objective of this study was to utilize therapeutic ultrasound in enhancing delivery of topical macromolecules into the cornea. Methods: Rabbit corneas were dissected and placed in a diffusion cell with a small ultra-red fluorescent protein (smURFP; molecular weight of 32,000 Da) as a macromolecule solution. The corneas were treated with continuous ultrasound application at frequencies of 400 or 600 kHz and intensities of 0.8 to 1.0 W/cm2 for 5 minutes, or sham-treated. Fluorescence imaging of the cornea sections was used to observe the delivery of macromolecules into individual epithelial cells. Spectrophotometric analysis at smURFP maximal absorbance of 640 nm was done to determine the presence of macromolecules in the receiver compartment. Safety of ultrasound application was studied through histology analysis. Results: Ultrasound-treated corneas showed smURFP delivery into epithelial cells by fluorescence in the cytoplasm, whereas sham-treated corneas lacked any appreciable fluorescence in the individual cells. The sham group showed 0% of subcellular penetration, whereas the 400 kHz ultrasound-treated group and 600 kHz ultrasound-treated group showed 31% and 57% of subcellular penetration, respectively. Spectrophotometry measurements indicated negligible presence of smURFP macromolecules in the receiver compartment solution in both the sham and ultrasound treatment groups, and these macromolecules did not cross the entire depth of the cornea. Histological studies showed no significant corneal damage due to ultrasound application. Conclusions: Therapeutic ultrasound application was shown to increase the delivery of smURFP macromolecules into the cornea. Translational Relevance: Our study offers a clinical potential for a minimally invasive macromolecular treatment of corneal diseases.


Assuntos
Doenças da Córnea , Terapia por Ultrassom , Animais , Córnea/diagnóstico por imagem , Córnea/metabolismo , Doenças da Córnea/metabolismo , Fluorescência , Substâncias Macromoleculares/metabolismo , Coelhos
9.
RSC Chem Biol ; 2(4): 1221-1226, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34458834

RESUMO

Self-labeling proteins have revolutionized super-resolution and sensor imaging. Tags recognize a bioorthogonal substrate for covalent attachment. We show the small Ultra-Red Fluorescent Protein (smURFP) is a self-labeling protein. The substrate is fluorogenic, fluoresces when attached, and quenches fluorescent cargo. The smURFP-tag has novel properties for tool development.

10.
Salud UNINORTE ; 37(2): 264-284, mayo-ago. 2021. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1377249

RESUMO

RESUMEN Objetivos: El propósito de este estudio fue determinar el desenlace en el egreso y en el seguimiento a un año de los pacientes con trauma craneoencefálico severo sometidos a craniectomía descompresiva primaria y secundaria en la Clínica de la Universidad de La Sabana, en un periodo de cinco años. Pacientes y métodos: Se llevó a cabo una serie de casos retrospectiva de pacientes con trauma craneoencefálico severo sometidos a craniectomía descompresiva entre 2008 y 2013. Los desenlaces primarios fueron la sobrevida y el estado funcional medido por la escala de desenlace de Glasgow al momento del egreso hospitalario y al año de seguimiento. Como desenlaces secundarios se incluyeron el tiempo de latencia para la realización de la craniectomía, las complicaciones intra- y postoperatorias, días de hospitalización y estancia en la unidad de cuidados intensivos, tiempo de ventilación, resultados de la craneoplastia y causa de muerte. Resultados: Treinta y cinco pacientes con trauma craneoencefálico severo fueron sometidos a craniectomía descompresiva en el periodo de estudio, 29 primarias y 6 secundarias, con una latencia mediana de 5 horas y 57 horas, respectivamente. Se observó una sobrevida del 51,4 % de los pacientes, de los cuales 39 % presentó recuperación funcional satisfactoria en la escala de desenlace de Glasgow en el momento del egreso y al año. Conclusiones: En este grupo de pacientes sometidos a craniectomía descompresiva primaria o secundaria, junto con un manejo interdisciplinario y rehabilitación precoz, se presentaron desenlaces funcionales favorables en el seguimiento a largo plazo.


ABSTRACT Aim: The purpose of this study was to determine the outcome, at discharge and at one-year follow-up, of patients with severe traumatic brain injury undergoing primary and secondary decompressive craniectomy at Clinica Universidad de La Sabana, over a period of five years. Patients and methods: We conducted a retrospective case series of patients with severe traumatic brain injury undergoing decompressive craniectomy between 2008 and 2013. Te primary outcomes were survival and functional status, measured by the Glasgow Outcome Scale, both at discharge, and at the one year follow-up. Secondary outcomes included latency time for craniectomy, intra and postoperative complications, days of hospitalization and intensive care unit stay, ventilation time, cranioplasty results, and cause of death. Results: Thirty-five patients with severe traumatic brain injury underwent decompressive craniectomy in the study period, 29 of which were primary and 6, secondary, with a median latency of 5 hours and 57 hours, respectively. A survival of 51.4% of the patients was observed, of which 39% presented satisfactory functional recovery on the Glasgow outcome scale at the time of discharge and one year later. Conclusions: In this group of patients who underwent primary or secondary decompressive craniectomy, together with interdisciplinary management and early rehabilitation, favorable functional outcomes were found in the long-term follow-up.

11.
Biochem Soc Trans ; 48(6): 2657-2667, 2020 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-33196077

RESUMO

Noninvasive fluorescent imaging requires far-red and near-infrared fluorescent proteins for deeper imaging. Near-infrared light penetrates biological tissue with blood vessels due to low absorbance, scattering, and reflection of light and has a greater signal-to-noise due to less autofluorescence. Far-red and near-infrared fluorescent proteins absorb light >600 nm to expand the color palette for imaging multiple biosensors and noninvasive in vivo imaging. The ideal fluorescent proteins are bright, photobleach minimally, express well in the desired cells, do not oligomerize, and generate or incorporate exogenous fluorophores efficiently. Coral-derived red fluorescent proteins require oxygen for fluorophore formation and release two hydrogen peroxide molecules. New fluorescent proteins based on phytochrome and phycobiliproteins use biliverdin IXα as fluorophores, do not require oxygen for maturation to image anaerobic organisms and tumor core, and do not generate hydrogen peroxide. The small Ultra-Red Fluorescent Protein (smURFP) was evolved from a cyanobacterial phycobiliprotein to covalently attach biliverdin as an exogenous fluorophore. The small Ultra-Red Fluorescent Protein is biophysically as bright as the enhanced green fluorescent protein, is exceptionally photostable, used for biosensor development, and visible in living mice. Novel applications of smURFP include in vitro protein diagnostics with attomolar (10-18 M) sensitivity, encapsulation in viral particles, and fluorescent protein nanoparticles. However, the availability of biliverdin limits the fluorescence of biliverdin-attaching fluorescent proteins; hence, extra biliverdin is needed to enhance brightness. New methods for improved biliverdin bioavailability are necessary to develop improved bright far-red and near-infrared fluorescent proteins for noninvasive imaging in vivo.


Assuntos
Biliverdina/química , Técnicas Biossensoriais , Corantes Fluorescentes/química , Espectrometria de Fluorescência/instrumentação , Animais , Antozoários , Biofísica , Cianobactérias/metabolismo , Proteínas de Fluorescência Verde/química , Humanos , Peróxido de Hidrogênio/química , Proteínas Luminescentes/química , Camundongos , Nanopartículas/química , Neoplasias/cirurgia , Oxigênio/química , Fotodegradação , Ficobilissomas/química , Fitocromo/química , Espalhamento de Radiação , Espectrometria de Fluorescência/métodos , Trichodesmium/metabolismo , Proteína Vermelha Fluorescente
12.
Sensors (Basel) ; 20(21)2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33158174

RESUMO

Imaging technologies are being deployed on cabled observatory networks worldwide. They allow for the monitoring of the biological activity of deep-sea organisms on temporal scales that were never attained before. In this paper, we customized Convolutional Neural Network image processing to track behavioral activities in an iconic conservation deep-sea species-the bubblegum coral Paragorgia arborea-in response to ambient oceanographic conditions at the Lofoten-Vesterålen observatory. Images and concomitant oceanographic data were taken hourly from February to June 2018. We considered coral activity in terms of bloated, semi-bloated and non-bloated surfaces, as proxy for polyp filtering, retraction and transient activity, respectively. A test accuracy of 90.47% was obtained. Chronobiology-oriented statistics and advanced Artificial Neural Network (ANN) multivariate regression modeling proved that a daily coral filtering rhythm occurs within one major dusk phase, being independent from tides. Polyp activity, in particular extrusion, increased from March to June, and was able to cope with an increase in chlorophyll concentration, indicating the existence of seasonality. Our study shows that it is possible to establish a model for the development of automated pipelines that are able to extract biological information from times series of images. These are helpful to obtain multidisciplinary information from cabled observatory infrastructures.


Assuntos
Antozoários/fisiologia , Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Periodicidade , Animais
13.
Nat Commun ; 11(1): 1848, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32296061

RESUMO

Genetically encoded Förster Resonance Energy Transfer (FRET)-based biosensors are powerful tools to illuminate spatiotemporal regulation of cell signaling in living cells, but the utility of the red spectrum for biosensing was limited due to a lack of bright and stable red fluorescent proteins. Here, we rationally improve the photophysical characteristics of the coral-derived fluorescent protein TagRFP-T. We show that a new single-residue mutant, super-TagRFP (stagRFP) has nearly twice the molecular brightness of TagRFP-T and negligible photoactivation. stagRFP facilitates significant improvements on multiple green-red biosensors as a FRET acceptor and is an efficient FRET donor that supports red/far-red FRET biosensing. Capitalizing on the ability of stagRFP to couple with multiple FRET partners, we develop a novel multiplex method to examine the confluence of signaling activities from three kinases simultaneously in single living cells, providing evidence for a role of Src family kinases in regulating growth factor induced Akt and ERK activities.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Proteínas Luminescentes/química , Humanos , Mutagênese/genética , Mutagênese/fisiologia , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Proteína Vermelha Fluorescente
14.
Sensors (Basel) ; 20(6)2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32183233

RESUMO

This paper presents the technological developments and the policy contexts for the project "Autonomous Robotic Sea-Floor Infrastructure for Bentho-Pelagic Monitoring" (ARIM). The development is based on the national experience with robotic component technologies that are combined and merged into a new product for autonomous and integrated ecological deep-sea monitoring. Traditional monitoring is often vessel-based and thus resource demanding. It is economically unviable to fulfill the current policy for ecosystem monitoring with traditional approaches. Thus, this project developed platforms for bentho-pelagic monitoring using an arrangement of crawler and stationary platforms at the Lofoten-Vesterålen (LoVe) observatory network (Norway). Visual and acoustic imaging along with standard oceanographic sensors have been combined to support advanced and continuous spatial-temporal monitoring near cold water coral mounds. Just as important is the automatic processing techniques under development that have been implemented to allow species (or categories of species) quantification (i.e., tracking and classification). At the same time, real-time outboard processed three-dimensional (3D) laser scanning has been implemented to increase mission autonomy capability, delivering quantifiable information on habitat features (i.e., for seascape approaches). The first version of platform autonomy has already been tested under controlled conditions with a tethered crawler exploring the vicinity of a cabled stationary instrumented garage. Our vision is that elimination of the tether in combination with inductive battery recharge trough fuel cell technology will facilitate self-sustained long-term autonomous operations over large areas, serving not only the needs of science, but also sub-sea industries like subsea oil and gas, and mining.


Assuntos
Ecossistema , Monitoramento Ambiental/métodos , Oceanografia/métodos , Oceanos e Mares , Acústica/instrumentação , Animais , Antozoários/fisiologia , Humanos , Robótica/instrumentação , Gravação em Vídeo/métodos
15.
Int J Biol Macromol ; 153: 100-106, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32105698

RESUMO

Nanoparticles are excellent imaging agents for cancer, but variability in chemical structure, racemic mixtures, and addition of heavy metals hinders FDA approval in the United States. We developed a small ultra-red fluorescent protein, named smURFP, to have optical properties similar to the small-molecule Cy5, a heptamethine subclass of cyanine dyes (Ex/Em = 642/670 nm). smURFP has a fluorescence quantum yield of 18% and expresses so well in E. coli, that gram quantities of fluorescent protein are purified from cultures in the laboratory. In this research, the fluorescent protein smURFP was combined with bovine serum albumin into fluorescent protein nanoparticles. These nanoparticles are fluorescent with a quantum yield of 17% and 12-14 nm in diameter. The far-red fluorescent protein nanoparticles noninvasively image tumors in living mice via the enhanced permeation and retention (EPR) mechanism. This manuscript describes the use of a new fluorescent protein nanoparticle for in vivo fluorescent imaging. This protein nanoparticle core should prove useful as a biomacromolecular scaffold, which could bear extended chemical modifications for studies, such as the in vivo imaging of fluorescent protein nanoparticles targeted to primary and metastatic cancer, theranostic treatment, and/or dual-modality imaging with positron emission tomography for entire human imaging.


Assuntos
Corantes Fluorescentes , Proteínas Luminescentes , Neoplasias Pulmonares , Nanopartículas/química , Imagem Óptica , Células A549 , Animais , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacocinética , Corantes Fluorescentes/farmacologia , Xenoenxertos , Humanos , Proteínas Luminescentes/química , Proteínas Luminescentes/farmacocinética , Proteínas Luminescentes/farmacologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Proteína Vermelha Fluorescente
16.
Opt Express ; 27(20): 28022-28035, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31684560

RESUMO

Non-degenerate two-photon excitation (ND-TPE) has been explored in two-photon excitation microscopy. However, a systematic study of the efficiency of ND-TPE to guide the selection of fluorophore excitation wavelengths is missing. We measured the relative non-degenerate two-photon absorption cross-section (ND-TPACS) of several commonly used fluorophores (two fluorescent proteins and three small-molecule dyes) and generated 2-dimensional ND-TPACS spectra. We observed that the shape of a ND-TPACS spectrum follows that of the corresponding degenerate two-photon absorption cross-section (D-TPACS) spectrum, but is higher in magnitude. We found that the observed enhancements are higher than theoretical predictions.

17.
ACS Chem Biol ; 14(7): 1449-1459, 2019 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-31120734

RESUMO

Clinical trials involving genome-edited cells are growing in popularity, where CAR-T immunotherapy and CRISPR/Cas9 editing are more recognized strategies. Genetic reporters are needed to localize the molecular events inside these cells in patients. Specifically, a nonimmunogenic genetic reporter is urgently needed as current reporters are immunogenic due to derivation from nonhuman sources. Prostate-specific membrane antigen (PSMA) is potentially nonimmunogenic due to its natural, low-level expression in select tissues (self-MHC display). PSMA overexpression on human prostate adenocarcinoma is also visible with excellent contrast. We exploit these properties in a transduced, two-component, Human-Derived, Genetic, Positron-emitting, and Fluorescent (HD-GPF) reporter system. Mechanistically analogous to the luciferase and luciferin reporter, PSMA is genetically encoded into non-PSMA expressing 8505C cells and tracked with ACUPA-Cy3-BF3, a single, systemically injected small molecule that delivers positron emitting fluoride (18F) and a fluorophore (Cy3) to report on cells expressing PSMA. PSMA-lentivirus transduced tissues become visible by Cy3 fluorescence, [18F]-positron emission tomography (PET), and γ-scintillated biodistribution. HD-GPF fluorescence is visible at subcellular resolution, while a reduced PET background is achieved in vivo, due to rapid ACUPA-Cy3-BF3 renal excretion. Co-transduction with luciferase and GFP show specific advantages over popular genetic reporters in advanced murine models including, a "mosaic" model of solid-tumor intratumoral heterogeneity and a survival model for observing postsurgical recurrence. We report an advanced genetic reporter that tracks genetically modified cells in entire animals and with subcellular resolution with PET and fluorescence, respectively. This reporter system is potentially nonimmunogenic and will therefore be useful in human studies. PSMA is a biomarker of prostate adenocarcinoma and ACUPA-Cy3-BF3 potential in radical prostatectomy is demonstrated.


Assuntos
Antígenos de Superfície/análise , Carbocianinas/análise , Corantes Fluorescentes/análise , Genes Reporter , Glutamato Carboxipeptidase II/análise , Neoplasias da Próstata/genética , Animais , Antígenos de Superfície/genética , Linhagem Celular Tumoral , Rastreamento de Células/métodos , Glutamato Carboxipeptidase II/genética , Humanos , Masculino , Camundongos , Modelos Moleculares , Imagem Óptica/métodos , Tomografia por Emissão de Pósitrons/métodos , Neoplasias da Próstata/diagnóstico por imagem
18.
J Spine Surg ; 4(3): 624-629, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30547128

RESUMO

BACKGROUND: Spinal fractures are becoming more frequent and should be handled as a severe and endemic pathology that requires timely diagnosis and adequate treatment. The classification of the AOSpine is currently the classification used for this type of fractures, not only for its approach, but to predict surgical management. METHODS: These patients had spinal fracture reduction procedures done through percutaneous way with expander endovertebral implants, and intraosseous fixation using SpineJack® intravertebral implants plus Cohesion® cement. Within the follow-up scheme, subsequent measurements were taken after a week, a month after surgery, 3 months after the procedure and after 6 months of follow-up. STATA® (Statistical Analysis System, version 12.1, SAS Institute Inc., Cary, NC, USA) was used for all analyzes. The Wilcoxon or Student's t-test was used for comparisons in pairs depending on the normality of the distribution. RESULTS: A clinical follow-up is performed to 20 consecutive patients experiencing spinal compression fractures (SCF) who received percutaneous treatment involving SpineJack® and Cohesion® cement, resulting in a statistically significant decrease of both pain and pain-related disability. No complications arose from the procedure. CONCLUSIONS: According to the observations, which reflect what is found in the world literature, this is an effective and safe way of handling SCF.

20.
J Cereb Blood Flow Metab ; 37(3): 776-786, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28054494

RESUMO

An agent for visualizing cells by positron emission tomography is described and used to label red blood cells. The labeled red blood cells are injected systemically so that intracranial hemorrhage can be visualized by positron emission tomography (PET). Red blood cells are labeled with 0.3 µg of a positron-emitting, fluorescent multimodal imaging probe, and used to non-invasively image cryolesion induced intracranial hemorrhage in a murine model (BALB/c, 2.36 × 108 cells, 100 µCi, <4 mm hemorrhage). Intracranial hemorrhage is confirmed by histology, fluorescence, bright-field, and PET ex vivo imaging. The low required activity, minimal mass, and high resolution of this technique make this strategy an attractive alternative for imaging intracranial hemorrhage. PET is one solution to a spectrum of issues that complicate single photon emission computed tomography (SPECT). For this reason, this application serves as a PET alternative to [99mTc]-agents, and SPECT technology that is used in 2 million annual medical procedures. PET contrast is also superior to gadolinium and iodide contrast angiography for its lack of clinical contraindications.


Assuntos
Hemorragias Intracranianas/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Animais , Eritrócitos/química , Radioisótopos de Flúor , Marcação por Isótopo , Métodos , Camundongos , Camundongos Endogâmicos BALB C , Tomografia por Emissão de Pósitrons/normas
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