RESUMEN
Senescent cells drive age-related tissue dysfunction partially through the induction of a chronic senescence-associated secretory phenotype (SASP)1. Mitochondria are major regulators of the SASP; however, the underlying mechanisms have not been elucidated2. Mitochondria are often essential for apoptosis, a cell fate distinct from cellular senescence. During apoptosis, widespread mitochondrial outer membrane permeabilization (MOMP) commits a cell to die3. Here we find that MOMP occurring in a subset of mitochondria is a feature of cellular senescence. This process, called minority MOMP (miMOMP), requires BAX and BAK macropores enabling the release of mitochondrial DNA (mtDNA) into the cytosol. Cytosolic mtDNA in turn activates the cGAS-STING pathway, a major regulator of the SASP. We find that inhibition of MOMP in vivo decreases inflammatory markers and improves healthspan in aged mice. Our results reveal that apoptosis and senescence are regulated by similar mitochondria-dependent mechanisms and that sublethal mitochondrial apoptotic stress is a major driver of the SASP. We provide proof-of-concept that inhibition of miMOMP-induced inflammation may be a therapeutic route to improve healthspan.
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Apoptosis , Senescencia Celular , Citosol , ADN Mitocondrial , Mitocondrias , Animales , Ratones , Citosol/metabolismo , ADN Mitocondrial/metabolismo , Mitocondrias/genética , Mitocondrias/metabolismo , Necrosis por Permeabilidad de la Transmembrana Mitocondrial , Prueba de Estudio Conceptual , Inflamación/metabolismo , Fenotipo , Longevidad , Envejecimiento SaludableRESUMEN
Cellular senescence is characterized by an irreversible cell cycle arrest as well as a pro-inflammatory phenotype, thought to contribute to aging and age-related diseases. Neutrophils have essential roles in inflammatory responses; however, in certain contexts their abundance is associated with a number of age-related diseases, including liver disease. The relationship between neutrophils and cellular senescence is not well understood. Here, we show that telomeres in non-immune cells are highly susceptible to oxidative damage caused by neighboring neutrophils. Neutrophils cause telomere dysfunction both in vitro and ex vivo in a ROS-dependent manner. In a mouse model of acute liver injury, depletion of neutrophils reduces telomere dysfunction and senescence. Finally, we show that senescent cells mediate the recruitment of neutrophils to the aged liver and propose that this may be a mechanism by which senescence spreads to surrounding cells. Our results suggest that interventions that counteract neutrophil-induced senescence may be beneficial during aging and age-related disease.
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Lesión Pulmonar Aguda/inmunología , Tetracloruro de Carbono/efectos adversos , Neutrófilos/citología , Especies Reactivas de Oxígeno/metabolismo , Acortamiento del Telómero , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/metabolismo , Animales , Línea Celular , Senescencia Celular , Técnicas de Cocultivo , Modelos Animales de Enfermedad , Femenino , Fibroblastos/citología , Fibroblastos/metabolismo , Humanos , Masculino , Ratones , Neutrófilos/metabolismo , Estrés Oxidativo , Comunicación ParacrinaRESUMEN
BACKGROUND: Red blood cell exchange is often used prophylactically in patients with sickle cell disease, with the goal to maintain hemoglobin S (HbS) below a target threshold level. We reviewed whether the daily "rate of rise" (RoR) in HbS that occurs between procedures can be used for patient management. For some patients not achieving their HbS goals despite efficient exchanges, the post-procedure hematocrit (Hct) target is increased to potentially suppress HbS production. This case series explores the utility of this approach, other clinical uses of the daily RoR in HbS, and the factors that influence it. STUDY DESIGN AND METHODS: A total of 660 procedures from 24 patients undergoing prophylactic RBC depletion/exchange procedures were included. Laboratory values and clinical parameters were collected and used to calculate the daily RoR in HbS. Factors such as Hct or medications that might influence the RoR in HbS were evaluated. RESULTS: The RoR in HbS varied widely between patients but remained relatively stable within individuals. Surprisingly, this value was not significantly influenced by changes in post-procedure Hct or concurrent hydroxyurea use. A patient's average RoR in HbS effectively predicted the pre-procedure HbS at the following visit (R2 = 0.65). DISCUSSION: The RoR in HbS is a relatively consistent parameter for individual patients that is unaffected by medication use or procedural Hct targets and may be useful in determining intervals between procedures.
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Anemia de Células Falciformes , Eliminación de Componentes Sanguíneos , Humanos , Hemoglobina Falciforme/análisis , Transfusión de Eritrocitos/efectos adversos , Anemia de Células Falciformes/terapia , HematócritoRESUMEN
Food safety and food security are two of the main concerns for the modern food manufacturing industry. Disruptions in the food supply and value chains have created the need to develop agile screening tools that will allow the detection of food pathogens, spoilage microorganisms, microbial contaminants, toxins, herbicides, and pesticides in agricultural commodities, natural products, and food ingredients. Most of the current routine analytical methods used to detect and identify microorganisms, herbicides, and pesticides in food ingredients and products are based on the use of reliable and robust immunological, microbiological, and biochemical techniques (e.g. antigen-antibody interactions, extraction and analysis of DNA) and chemical methods (e.g. chromatography). However, the food manufacturing industries are demanding agile and affordable analytical methods. The objective of this review is to highlight the advantages and limitations of the use of vibrational spectroscopy combined with chemometrics as proxy to evaluate and quantify herbicides, pesticides, and toxins in foods.
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Ingredientes Alimentarios , Herbicidas , Plaguicidas , Inocuidad de los Alimentos , Plaguicidas/análisis , Análisis Espectral , Herbicidas/análisis , Ingredientes Alimentarios/análisisRESUMEN
Genetic processes require the activity of multiple topoisomerases, essential enzymes that remove topological tension and intermolecular linkages in DNA. We have investigated the subcellular localisation and activity of the six human topoisomerases with a view to understanding the topological maintenance of human mitochondrial DNA. Our results indicate that mitochondria contain two topoisomerases, TOP1MT and TOP3A. Using molecular, genomic and biochemical methods we find that both proteins contribute to mtDNA replication, in addition to the decatenation role of TOP3A, and that TOP1MT is stimulated by mtSSB. Loss of TOP3A or TOP1MT also dysregulates mitochondrial gene expression, and both proteins promote transcription elongation in vitro. We find no evidence for TOP2 localisation to mitochondria, and TOP2B knockout does not affect mtDNA maintenance or expression. Our results suggest a division of labour between TOP3A and TOP1MT in mtDNA topology control that is required for the proper maintenance and expression of human mtDNA.
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ADN Mitocondrial , Mitocondrias , Humanos , Mitocondrias/metabolismo , ADN Mitocondrial/metabolismo , ADN-Topoisomerasas de Tipo I/metabolismo , Replicación del ADN/genética , ADN-Topoisomerasas/genéticaRESUMEN
In recent years, transcatheter edge-to-edge repair (TEER) has been widely adopted as an effective treatment for mitral regurgitation (MR). The aim of this study is to develop a personalized in silico model to predict the effect of edge-to-edge repair in advance to the procedure for each individual patient. For this purpose, we propose a combination of a valve deformation model for computing the mitral valve (MV) orifice area (MVOA) and a lumped parameter model for the hemodynamics, specifically mitral regurgitation volume (RVol). Although we cannot obtain detailed information on the three-dimensional flow field near the mitral valve, we can rapidly simulate the important medical parameters for the clinical decision support. In the present method, we construct the patient-specific pre-operative models by using the parameter optimization and then simulate the postoperative state by applying the additional clipping condition. The computed preclip MVOAs show good agreement with the clinical measurements, and the correlation coefficient takes 0.998. In addition, the MR grade in terms of RVol also has good correlation with the grade by ground truth MVOA. Finally, we try to investigate the applicability for the predicting the postclip state. The simulated valve shapes clearly show the well-known double orifice and the improvement of the MVOA, compared with the preclip state. Similarly, we confirmed the improved reverse flow and MR grade in terms of RVol. A total computational time is approximately 8 h by using general-purpose PC. These results obviously indicate that the present in silico model has good capability for the assessment of edge-to-edge repair.
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Implantación de Prótesis de Válvulas Cardíacas , Insuficiencia de la Válvula Mitral , Humanos , Insuficiencia de la Válvula Mitral/cirugía , Implantación de Prótesis de Válvulas Cardíacas/métodos , Válvula Mitral/cirugía , Resultado del Tratamiento , Simulación por ComputadorRESUMEN
Cellular senescence has been shown to contribute to skin ageing. However, the role of melanocytes in the process is understudied. Our data show that melanocytes are the only epidermal cell type to express the senescence marker p16INK4A during human skin ageing. Aged melanocytes also display additional markers of senescence such as reduced HMGB1 and dysfunctional telomeres, without detectable telomere shortening. Additionally, senescent melanocyte SASP induces telomere dysfunction in paracrine manner and limits proliferation of surrounding cells via activation of CXCR3-dependent mitochondrial ROS. Finally, senescent melanocytes impair basal keratinocyte proliferation and contribute to epidermal atrophy in vitro using 3D human epidermal equivalents. Crucially, clearance of senescent melanocytes using the senolytic drug ABT737 or treatment with mitochondria-targeted antioxidant MitoQ suppressed this effect. In conclusion, our study provides proof-of-concept evidence that senescent melanocytes affect keratinocyte function and act as drivers of human skin ageing.
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Envejecimiento/patología , Atrofia/patología , Senescencia Celular , Melanocitos/patología , Piel/patología , Telómero/patología , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento/efectos de los fármacos , Atrofia/inducido químicamente , Células Cultivadas , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Epidermis/efectos de los fármacos , Epidermis/patología , Femenino , Humanos , Masculino , Melanocitos/metabolismo , Persona de Mediana Edad , Comunicación Paracrina , Especies Reactivas de Oxígeno/metabolismo , Receptores CXCR4/metabolismo , Piel/metabolismo , Telómero/metabolismo , Adulto JovenRESUMEN
Ageing is the biggest risk factor for cardiovascular disease. Cellular senescence, a process driven in part by telomere shortening, has been implicated in age-related tissue dysfunction. Here, we address the question of how senescence is induced in rarely dividing/post-mitotic cardiomyocytes and investigate whether clearance of senescent cells attenuates age-related cardiac dysfunction. During ageing, human and murine cardiomyocytes acquire a senescent-like phenotype characterised by persistent DNA damage at telomere regions that can be driven by mitochondrial dysfunction and crucially can occur independently of cell division and telomere length. Length-independent telomere damage in cardiomyocytes activates the classical senescence-inducing pathways, p21CIP and p16INK4a, and results in a non-canonical senescence-associated secretory phenotype, which is pro-fibrotic and pro-hypertrophic. Pharmacological or genetic clearance of senescent cells in mice alleviates detrimental features of cardiac ageing, including myocardial hypertrophy and fibrosis. Our data describe a mechanism by which senescence can occur and contribute to age-related myocardial dysfunction and in the wider setting to ageing in post-mitotic tissues.
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Cardiomegalia/patología , Senescencia Celular , Daño del ADN , Fibrosis/patología , Mitosis , Miocitos Cardíacos/patología , Acortamiento del Telómero , Envejecimiento , Animales , Cardiomegalia/etiología , Femenino , Fibrosis/etiología , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Monoaminooxidasa/fisiología , Miocitos Cardíacos/metabolismo , Fenotipo , ARN/fisiología , Ratas Sprague-Dawley , Telomerasa/fisiologíaRESUMEN
Patients undergoing recurrent platelet transfusions can become refractory to these transfusions. Platelet antibody screens (Immucor), platelet crossmatching assays (Immucor), and HLA antibody testing are commonly used to test these patients. The relative effectiveness of these tests has not been determined. A higher incidence of strongly positive screen results that did not predict crossmatch results was anecdotally noted. Therefore, the results of the platelet antibody screens and crossmatches were systematically compiled over a 12-year period from 2010 to 2021. Of note, the Immucor Capture-P Ready Screen (platelet antibody) had a recall in March 2013 after which the performance of the test appears to have changed. The positivity rate of the platelet antibody screen increased over the course of the study, and this was statistically significant when analyzing year as a continuous variable and when grouping years by four-year periods (2010-13,2014-17,2018-21). In contrast, platelet crossmatch reactivity decreased slightly throughout this period. During the 2018-21 period, HLA antibody testing was commonly performed and correlated well with the crossmatch testing but not with the screen. These results suggest that the drastic increase in positivity we observed in the platelet antibody screen over this period is due to increased analytic sensitivity (with possible reduced specificity) of the screen and not a change in our patient population. Based on these results, the platelet antibody screen has little clinical utility and directly performing platelet crossmatching or HLA antibody testing is recommended for patients suspected to be refractory to platelet transfusions due to alloimmune-mediated factors.
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Antígenos HLA , Transfusión de Plaquetas , Humanos , Plaquetas , Prueba de Histocompatibilidad , Tipificación y Pruebas Cruzadas Sanguíneas , IsoanticuerposRESUMEN
The aim of this study was to evaluate the ability of a droplet collar accessory attached to a portable near-infrared (NIR) instrument to characterize the artificial contamination of methanol in commercial whisky samples. Unadulterated samples (n = 12) were purchased from local bottle shops where adulterated samples were created by adding methanol (99% pure methanol) at six levels (0.5%, 1%, 2%, 3%, 4% and 5% v/v) to the commercial whisky samples (controls). Samples were analyzed using a drop collar accessory attached to a MicroNIR Onsite instrument (900-1650 nm). Partial least squares (PLS) cross-validation statistics obtained for the prediction of all levels of methanol (from 0 to 5%) addition were considered adequate when the whole adulteration range was used, coefficient of determination in cross-validation (R2cv: 0.95) and standard error in cross of validation (SECV: 0.35% v/v). The cross-validation statistics were R2cv: 0.97, SECV: 0.28% v/v after the 0.5% and 1% v/v methanol addition was removed. These results showed the ability of using a new sample presentation attachment to a portable NIR instrument to analyze the adulteration of whisky with methanol. However, the low levels of methanol adulteration (0.5 and 1%) were not well predicted using the NIR method evaluated.
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Metanol , Espectroscopía Infrarroja Corta , Espectroscopía Infrarroja Corta/métodos , Contaminación de Alimentos/análisis , Análisis de los Mínimos CuadradosRESUMEN
Current therapeutic drugs for Alzheimer's disease (AD) can only offer limited symptomatic benefits and do not halt disease progression. Multitargeted directed ligands (MTDLs) have been considered to be a feasible way to treat AD due to the multiple neuropathological processes in AD. Previous studies proposed that compounds containing two aromatic groups connected by a carbon chain should act as effective amyloid ß (Aß) aggregation inhibitors although the optimal length of the carbon chain has not been explored. In the current study, a series of naphthalimide analogs were designed and synthesized based on the proposed structure and multiple bioactivities beneficial to the AD treatment were reported. In vitro studies showed that compound 8, which has two aromatic groups connected by a two-carbon chain, exhibited significant inhibition of Aß aggregation through the prevention of elongation and association of Aß fibril growth. Furthermore, this compound also displayed antioxidative activities and neuroprotection from Aß monomer induced toxicity in primary cortical neurons. The results of the present study highlight a novel naphthalimide-based compound 8 as a promising MTDL against AD. Its structural elements can be further explored for enhanced therapeutic capabilities.
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Enfermedad de Alzheimer , Humanos , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides , Naftalimidas/farmacología , Naftalimidas/uso terapéutico , Ligandos , Antioxidantes/farmacología , Inhibidores de la Colinesterasa/químicaRESUMEN
INTRODUCTION: Sternal fractures (SF) are uncommon injuries usually associated with a significant mechanism of injury. Concomitant injury is likely, and a risk of mortality is substantial. AIM: Our aim in this study was to identify the risk factors for mortality in patients who had sustained sternal fractures. METHODS: We conducted a single centre retrospective review of the trust's Trauma Audit and Research Network Database, from May 2014 to July 2021. Our inclusion criteria were any patients who had sustained a sternal fracture. The regions of injury were defined using the Abbreviated Injury Score. Pearson Chi-Squared, Fisher Exact tests and multivariate regression analyses were performed using IBM SPSS. RESULTS: A total of 249 patients were identified to have sustained a SF. There were 19 patients (7.63%) who had died. The most common concomitant injuries with SF were Rib fractures (56%), Lung Contusions (31.15%) and Haemothorax (21.88%). There was a significant increase in age (59.93 vs 70.06, p = .037) and admission troponin (36.34 vs. 100.50, p = .003) in those who died. There was a significantly lower GCS in those who died (10.05 vs. 14.01, p < .001). On multi regression analysis, bilateral rib injury (p = 0.037, OR 1.104) was the only nominal variable which showed significance in mortality. CONCLUSION: Sternal Fractures are uncommon but serious injuries. Our review has identified that bilateral rib injuries, increase in age, low GCS, and high admission troponin in the context of SF, were associated with mortality.
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Fracturas de las Costillas , Traumatismos Torácicos , Humanos , Centros Traumatológicos , Esternón/lesiones , Traumatismos Torácicos/epidemiología , Traumatismos Torácicos/complicaciones , Fracturas de las Costillas/epidemiología , Factores de Riesgo , Estudios Retrospectivos , Puntaje de Gravedad del TraumatismoRESUMEN
During apoptosis, pro-apoptotic BAX and BAK are activated, causing mitochondrial outer membrane permeabilisation (MOMP), caspase activation and cell death. However, even in the absence of caspase activity, cells usually die following MOMP Such caspase-independent cell death is accompanied by inflammation that requires mitochondrial DNA (mtDNA) activation of cGAS-STING signalling. Because the mitochondrial inner membrane is thought to remain intact during apoptosis, we sought to address how matrix mtDNA could activate the cytosolic cGAS-STING signalling pathway. Using super-resolution imaging, we show that mtDNA is efficiently released from mitochondria following MOMP In a temporal manner, we find that following MOMP, BAX/BAK-mediated mitochondrial outer membrane pores gradually widen. This allows extrusion of the mitochondrial inner membrane into the cytosol whereupon it permeablises allowing mtDNA release. Our data demonstrate that mitochondrial inner membrane permeabilisation (MIMP) can occur during cell death following BAX/BAK-dependent MOMP Importantly, by enabling the cytosolic release of mtDNA, inner membrane permeabilisation underpins the immunogenic effects of caspase-independent cell death.
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Apoptosis , ADN Mitocondrial/metabolismo , Mitocondrias/metabolismo , Membranas Mitocondriales/metabolismo , Animales , Línea Celular Tumoral , ADN Mitocondrial/genética , Humanos , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones , Mitocondrias/genética , Nucleotidiltransferasas/genética , Nucleotidiltransferasas/metabolismo , PermeabilidadRESUMEN
BACKGROUND: A direct antiglobulin test (DAT) checks for antibody or complement on the surface of RBCs and is often done following a transfusion reaction. While passive anti-A and anti-B antibodies are known to cause positive DATs, the extent this occurs following transfusion is unknown. STUDY DESIGN AND METHODS: DAT results, ABO type, eluate information, and blood product information were recorded on 1097 transfusion reactions at a large academic hospital over 8 years. The effect of patient blood type, product type, and plasma compatibility of blood product transfused on DAT results were determined. Statistical significance was determined using Chi-squared testing. RESULTS: Patient ABO blood type was a strong predictor of a positive DAT, with type O patients having 6.7% positive rate and non-O patients having a positive rate of 20.6% (p < .0001). Plasma compatibility of the product was a strong predictor of a positive DAT, with plasma compatible transfusions having a 9.4% positive rate while plasma incompatible transfusions were positive 44% of the time (p < .0001). Elution studies found that anti-A/B antibodies were the most common antibody identified. Platelets were more likely to be associated with a positive DAT when compared with RBC transfusions (p < .05). CONCLUSIONS: These results demonstrate the patient ABO type and plasma incompatibility are strong predictors of positive DAT results following a transfusion reaction. Anti-A and anti-B antibodies are estimated to account for about 50% of positive DATs in this study.
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Sistema del Grupo Sanguíneo ABO , Reacción a la Transfusión , Anticuerpos , Incompatibilidad de Grupos Sanguíneos , Tipificación y Pruebas Cruzadas Sanguíneas , Prueba de Coombs , HumanosRESUMEN
By 2050, the global population is projected to be in excess of nine billion people. This will result in an increased burden and stress on the food production systems, particularly in adjustments to several stages of the value chain that will require improvements and/or modifications in their effectiveness such as reducing waste, adapting to climate change, food security, and health. Disruptions such as digital agriculture, digital food, food agility, big data, have been utilized to characterize the changes in the way agro-food systems evolve and function, as well as in the approach they have been analyzed, measured, and monitored. It has been long recognized that the food industry is considered as a data driven enterprise. These characteristics are very important as the food industry becomes global and sustainable. The food industry is currently undergoing significant changes, and with this, challenges are occurring. These challenges are brought about from the food chains, climate changes, and the ability to be resilient in the production of food. Furthermore, health and cultural changes to food are occurring, where the diseases of obesity, diabetes, and aging in the population will continue to change the consumer's patterns and choices; whereby the consumer will be persuaded to choose and eat healthy and more nutritious foods. Indeed, the cultural awareness and social innovation to prevent food waste and therefore improve food security and sustainability will also prove to further complexities. This short review will briefly discuss some of the forefront issues in food value chains with a focus on using technology.
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Alimentos , Eliminación de Residuos , Agricultura , Cambio Climático , Abastecimiento de Alimentos , HumanosRESUMEN
For many years, an extensive array of chemometric methods have provided a platform upon which a quantitative description of environmental conditions can be obtained. Applying chemometric methods to environmental data allows us to identify and describe the interrelations between certain environmental drivers. They also provide an insight into the interrelationships between these drivers and afford us a greater understanding of the potential impact that these drivers can place upon the environment. However, an effective marriage of these two systems has not been performed. Therefore, it is the aim of this review to highlight the advantages of using chemometrics and sensors to identify hidden trends in environmental parameters, which allow the state of the environment to be effectively monitored. Despite the combination of chemometrics and sensors, to capture new developments and applications in the field of environmental sciences, these methods have not been extensively used. Importantly, although different parameters and monitoring procedures are required for different environments (e.g., air, water, soil), they are not distinct, separate entities. Contemporary developments in the use of chemometrics afford us the ability to predict changes in different aspects of the environment using instrumental methods. This review also provides an insight into the prevailing trends and the future of environmental sensing, highlighting that chemometrics can be used to enhance our ability to monitor the environment. This enhanced ability to monitor environmental conditions and to predict trends would be beneficial to government and research agencies in their ability to develop environmental policies and analysis procedures.
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Monitoreo del Ambiente , Contaminación Ambiental/análisis , Política AmbientalRESUMEN
The mechanisms driving crustal deformation and uplift of orogenic plateaus are fundamental to continental tectonics. Large-scale crustal flow has been hypothesized to occur in eastern Tibet, but it remains controversial due to a lack of geologic evidence. Geochemical and isotopic data from Cenozoic igneous rocks in the eastern Tibet-Gongga-Zheduo intrusive massif, provide a way to test this model. Modeling results suggest that Cenozoic magmas originated at depths of â¼30-40 km, the depth that crustal flow has been postulated to occur at. Detailed isotopic analyses indicate that the igneous rocks are derived from partial melting of the local Songpan-Ganzi crust, arguing against a long-distance crustal flow. Episodic magmatism during the Cenozoic showing a repeated shifting of magmatic sources can be correlated with crustal uplift. The continued indentation of the Indian Block and upwelling of the asthenosphere contribute to the crustal deformation, magmatism, and uplift.
RESUMEN
UV-visible spectroscopy (UV-Vis) is routinely used in microbiology as a tool to check the optical density (OD) pertaining to the growth stages of microbial cultures at the single wavelength of 600 nm, better known as the OD600 . Typically, modern UV-Vis spectrophotometers can scan in the region of approximately 200-1000 nm in the electromagnetic spectrum, where users do not extend the use of the instrument's full capability in a laboratory. In this study, the full potential of UV-Vis spectrophotometry (multiwavelength collection) was used to examine bacterial growth phases when treated with antibiotics showcasing the ability to understand the point of resistance when an antibiotic is introduced into the media and therefore understand the biochemical changes of the infectious pathogens. A multiplate reader demonstrated a high throughput experiment (96 samples) to understand the growth of Escherichia coli when varied concentrations of the antibiotic tetracycline was added into the well plates. Principal component analysis (PCA) and partial least squares discriminant analysis were then used as the data mining techniques to interpret the UV-Vis spectral data and generate machine learning "proof of principle" for the UV-Vis spectrophotometer plate reader. Results from this study showed that the PCA analysis provides an accurate yet simple visual classification and the recognition of E. coli samples belonging to each treatment. These data show significant advantages when compared to the traditional OD600 method where we can now understand biochemical changes in the system rather than a mere optical density measurement. Due to the unique experimental setup and procedure that involves indirect use of antibiotics, the same test could be used for obtaining practical information on the type, resistance, and dose of antibiotic necessary to establish the optimum diagnosis, treatment, and decontamination strategies for pathogenic and antibiotic resistant species.
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Escherichia coli/crecimiento & desarrollo , Aprendizaje Automático , Modelos Biológicos , Resistencia a la Tetraciclina , Espectrofotometría UltravioletaRESUMEN
OBJECTIVES: The use of online imagery by non-local observers to conduct remote, centralized collection of streetscape audit data in international studies has the potential to enhance efficiency of collection and comparability of such data for research on built environments and health. The objectives of the study were to measure (1) the consistency in responses between local in-field observers and non-local remote online observers and (2) the reliability between in-country online observers and non-local remote online observers using the Microscale Audit of Pedestrian Streetscapes Global tool to characterize pedestrian-related features along streets in five countries. METHODS: Consistency and inter-rater reliability were analyzed between local and non-local observers on a pooled database of 200 routes in five study regions (Melbourne, Australia; Ghent, Belgium; Curitiba, Brazil; Hong Kong, China; and Valencia, Spain) for microscale environmental feature subscales and item-level variables using the intraclass correlation coefficient (ICC). RESULTS: A local in-field versus remote online comparison had an ICC of 0.75 (95 % CI: 0.68-0.80) for the grand total score. An ICC of 0.91 (95 % CI: 0.88-0.93) was found for the local online versus remote online comparison. Positive subscales yielded stronger results in comparison to negative subscales, except for the similarly poor-performing positive aesthetics/social characteristics. CONCLUSIONS: This study demonstrated remote audits of microscale built environments using online imagery had good reliability with local in-field audits and excellent reliability with local online audits. Results generally supported remote online environmental audits as comparable to local online audits. This identification of low-cost and efficient data acquisition methods is important for expanding research on microscale built environments and physical activity globally.