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1.
Appl Opt ; 56(18): 5295-5300, 2017 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-29047583

RESUMEN

High-resolution spectrographs extract detailed spectral information of a sample and are frequently used in astronomy, laser-induced breakdown spectroscopy, and Raman spectroscopy. These instruments employ dispersive elements such as prisms and diffraction gratings to spatially separate different wavelengths of light, which are then detected by a charge-coupled device (CCD) or complementary metal-oxide-semiconductor (CMOS) detector array. Precise alignment along the optical axis (focus position) of the detector array is critical to maximize the instrumental resolution; however, traditional approaches of scanning the detector through focus lack a quantitative measure of precision, limiting the repeatability and relying on one's experience. Here we propose a method to evaluate the focus alignment of spectrograph detector arrays by establishing confidence intervals to measure the alignment precision. We show that propagation of uncertainty can be used to estimate the variance in an alignment, thus providing a quantitative and repeatable means to evaluate the precision and confidence of an alignment. We test the approach by aligning the detector array of a prototype miniature echelle spectrograph. The results indicate that the procedure effectively quantifies alignment precision, enabling one to objectively determine when an alignment has reached an acceptable level. This quantitative approach also provides a foundation for further optimization, including automated alignment. Furthermore, the procedure introduced here can be extended to other alignment techniques that rely on numerically fitting data to a model, providing a general framework for evaluating the precision of alignment methods.

2.
Clin Pharmacol Ther ; 108(5): 929-948, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32347548

RESUMEN

The complexity of integrating microbiota into clinical pharmacology, environmental toxicology, and opioid studies arises from bidirectional and multiscale interactions between humans and their many microbiota, notably those of the gut. Hosts and each microbiota are governed by distinct central dogmas, with genetics influencing transcriptomics, proteomics, and metabolomics. Each microbiota's metabolome differentially modulates its own and the host's multi-omics. Exogenous compounds (e.g., drugs and toxins), often affect host multi-omics differently than microbiota multi-omics, shifting the balance between drug efficacy and toxicity. The complexity of the host-microbiota connection has been informed by current methods of in vitro bacterial cultures and in vivo mouse models, but they fail to elucidate mechanistic details. Together, in vitro organ-on-chip microphysiological models, multi-omics, and in silico computational models have the potential to supplement the established methods to help clinical pharmacologists and environmental toxicologists unravel the myriad of connections between the gut microbiota and host health and disease.


Asunto(s)
Bacterias/efectos de los fármacos , Encéfalo/efectos de los fármacos , Microbioma Gastrointestinal/efectos de los fármacos , Genómica , Intestinos/microbiología , Hígado/efectos de los fármacos , Metabolómica , Procedimientos Analíticos en Microchip , Animales , Bacterias/metabolismo , Encéfalo/metabolismo , Simulación por Computador , Dieta/efectos adversos , Interacciones Huésped-Patógeno , Humanos , Dispositivos Laboratorio en un Chip , Hígado/metabolismo , Metaboloma , Modelos Animales , Modelos Biológicos
3.
J Control Release ; 186: 22-31, 2014 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-24815422

RESUMEN

Diabetic cardiomyopathy (DCM) is the leading cause of morbidity and mortality among the diabetic patients and currently there is no effective means to reverse its pathological progress. Basic fibroblast growth factor (bFGF) has shown promise as a molecular therapy for DCM, but its delivery is inefficient and non-specific. In the present study, a therapy combining nanoparticle (NP) carrier and ultrasound-targeted microbubble destruction (UTMD) was reported the first time for bFGF delivery to the heart of diabetic rats. bFGF-loaded NP (bFGF-NP) were prepared with Poloxamer 188-grafted heparin copolymer using water-in-water technique, and the morphology, encapsulation efficiency, and bioactivity of bFGF-NP were studied. The cellular uptake and cytotoxicity of bFGF-NP were evaluated with primary cultures of the left ventricular (LV) cardiomyocytes in vitro. Therapeutic effects of bFGF-NP/UTMD on the heart of DCM rats were studied by measuring LV systolic and diastolic functions, hemodynamic characteristics and indicators of cardiac remodeling including myocardial collagen volume fraction and capillary density. Results demonstrated that bFGF-NP showed good round morphology, efficient bFGF encapsulation and stable bioactivity of bFGF in vitro. bFGF-NP/UTMD combined treatment significantly enhanced the efficiency of bFGF cellular uptake (P<0.05) without obvious cytotoxicity. Significant improvements (P<0.05) in both cardiac functions and tissue morphology in the DCM rats were observed in bFGF-NP/UTMD group. These were not achievable using free bFGF, bFGF-NP or UTMD treatment alone. Our results show that combining a non-viral vector with UTMD technique is an effective strategy to deliver bFGF to the heart, and the resulting growth factor therapy has demonstrated potential to reverse the progress of DCM by restoring the cardiac functions and even the structure of damaged cardiac tissues.


Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Cardiomiopatías Diabéticas/tratamiento farmacológico , Factor 2 de Crecimiento de Fibroblastos/administración & dosificación , Microburbujas , Nanopartículas/administración & dosificación , Animales , Colágeno/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patología , Diabetes Mellitus Experimental/fisiopatología , Cardiomiopatías Diabéticas/metabolismo , Cardiomiopatías Diabéticas/patología , Cardiomiopatías Diabéticas/fisiopatología , Factor 2 de Crecimiento de Fibroblastos/química , Corazón/efectos de los fármacos , Corazón/fisiopatología , Heparina/química , Miocardio/metabolismo , Miocardio/patología , Nanopartículas/química , Poloxámero/química , Ratas Sprague-Dawley , Ultrasonido , Función Ventricular Izquierda/efectos de los fármacos
4.
Development ; 132(16): 3705-15, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16077090

RESUMEN

Developmental genetic analysis has shown that embryos of the parasitoid wasp Nasonia vitripennis depend more on zygotic gene products to direct axial patterning than do Drosophila embryos. In Drosophila, anterior axial patterning is largely established by bicoid, a rapidly evolving maternal-effect gene, working with hunchback, which is expressed both maternally and zygotically. Here, we focus on a comparative analysis of Nasonia hunchback function and expression. We find that a lesion in Nasonia hunchback is responsible for the severe zygotic headless mutant phenotype, in which most head structures and the thorax are deleted, as are the three most posterior abdominal segments. This defines a major role for zygotic Nasonia hunchback in anterior patterning, more extensive than the functions described for hunchback in Drosophila or Tribolium. Despite the major zygotic role of Nasonia hunchback, we find that it is strongly expressed maternally, as well as zygotically. Nasonia Hunchback embryonic expression appears to be generally conserved; however, the mRNA expression differs from that of Drosophila hunchback in the early blastoderm. We also find that the maternal hunchback message decays at an earlier developmental stage in Nasonia than in Drosophila, which could reduce the relative influence of maternal products in Nasonia embryos. Finally, we extend the comparisons of Nasonia and Drosophila hunchback mutant phenotypes, and propose that the more severe Nasonia hunchback mutant phenotype may be a consequence of differences in functionally overlapping regulatory circuitry.


Asunto(s)
Tipificación del Cuerpo , Proteínas de Unión al ADN/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas de Insectos/metabolismo , Factores de Transcripción/metabolismo , Avispas , Animales , Secuencia de Bases , Proteínas de Unión al ADN/genética , Proteínas de Drosophila/genética , Regulación del Desarrollo de la Expresión Génica , Ligamiento Genético , Proteínas HMGB/genética , Proteínas HMGB/metabolismo , Hibridación in Situ , Proteínas de Insectos/genética , Datos de Secuencia Molecular , ARN Mensajero Almacenado/metabolismo , Alineación de Secuencia , Factores de Transcripción TCF , Proteína 1 Similar al Factor de Transcripción 7 , Factores de Transcripción/genética , Avispas/anatomía & histología , Avispas/embriología
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