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1.
J Am Chem Soc ; 136(45): 15853-6, 2014 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-25329769

RESUMEN

A first approach toward understanding the targeted design of molecular photoacoustic contrast agents (MPACs) is presented. Optical and photoacoustic Z-scan spectroscopy was used to identify how nonlinear (excited-state) absorption contributes to enhancing the photoacoustic emission of the curcuminBF2 and bis-styryl (MeOPh)2BODIPY dyes relative to Cy3.


Asunto(s)
Absorción Fisicoquímica , Compuestos de Boro/química , Medios de Contraste/química , Imagen Óptica/métodos , Técnicas Fotoacústicas/métodos , Colorantes/química , Diseño de Fármacos
2.
Inorg Chem ; 53(11): 5556-67, 2014 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-24840779

RESUMEN

A series of ruthenium polypyridyl complexes are presented incorporating π-extended electron rich derivatives of the 8-oxyquinolate (OQN) ligand. The π-donating property of the OQN ligand introduces covalent character to the Ru(dπ)-OQN(π) bonding scheme enhancing its light harvesting properties and diversifying its redox properties, relative to the classic ruthenium(II) trisbipyridyl complex [Ru(bpy)3](2+). Synthesis and characterization is presented for the complexes [Ru(bpy)2(R-OQN)](PF6), where bpy = 2,2'-bipyridine and R = 5-phenyl, 5,7-diphenyl, 2,4-diphenyl, 5,7-bis(4-methoxyphenyl), 5,7-bis(4-(diphenylamino)phenyl). A comprehensive bonding analysis is presented for the [Ru(bpy)2(OQN)](+) system illustrating the origin of its unique spectroscopic and redox properties relative to [Ru(bpy)3](2+). This model is then extended to enable a consistent interpretation of spectra and redox properties for the π-extended [Ru(bpy)2(R-OQN)](PF6) series. Electronic structures have been probed experimentally by a combination of electrochemical and spectroscopic techniques (UV-vis-NIR absorption, emission, EPR spectroscopy) where (metal-ligand)-to-ligand (MLLCT) charge-transfer properties are described by time dependent-density functional theory (TD-DFT) analysis, at the B3LYP/6-31g(d,p) level of approximation. Substantial mixing, due to bonding and antibonding combinations of Ru(dπ) and OQN(π) orbitals, is observed at the HOMO and HOMO-3 levels for the ruthenium-oxyanion bond in [Ru(bpy)2(OQN)](+), which is responsible for the low-energy MLLCT based electronic transition and destabilization of the HOMO level viz. cyclic voltammetry. This noninnocent π-bonding phenomenon is consistent throughout the series which allows for controlled tuning of complex redox potentials while maintaining panchromatic absorption properties across the visible spectrum. Extensive charge delocalization is observed for the one-electron oxidized species using a combination of UV-vis-NIR, EPR spectroelectrochemistry, and Mulliken spin-density analysis, giving strong evidence for hole-delocalization across the delocalized Ru(dπ)-OQN(π) system, in particular for the electron rich 5,7-bis(4-methoxyphenyl) and 5,7-bis(4-(diphenylamino)phenyl) systems.

3.
Chem Phys Lett ; 608: 303-307, 2014 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-25242819

RESUMEN

The nonlinear optical properties of a series of pyrrolic compounds consisting of BODIPY and aza-BODIPY systems are investigated using 532 nm nanosecond laser and the Z-scan technique. Results show that 3,5-distyryl extension of BODIPY to the red shifted MeO2BODIPY dye has a dramatic impact on its nonlinear absorption properties changing it from a saturable absorber to an efficient reverse saturable absorbing material with a nonlinear absorption coefficient of 4.64 × 10-10 m/W. When plotted on a concentration scale per mole of dye in solution MeO2BODIPY far outperforms the recognized zinc(II) phthalocyanine dye and is comparable to that of zinc(II) tetraphenylporphyrin.

4.
Sci Rep ; 14(1): 21791, 2024 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-39294210

RESUMEN

Visitors to Colter Bay Village in Grand Teton National Park were surveyed to elicit their evaluations of experimental outdoor lighting conditions. Luminaires capable of dimming and switching between two LED modules (white, blended red-white) were installed in street and parking areas. The blended red-white lamps consisted of 30 narrowband LED with a peak wavelength 623 nm and two 3000 K white LEDs. Similar "red" lamps were previously shown to reduce impacts to bats and insects. The white and red lamps were closely matched for luminance. Measured horizontal illuminance at survey locations had an interquartile range from 0.63 to 3.82 lx. The red lamps produced lower perceived brightness (VB2(λ)), even after reflection off asphalt, yet survey participants expressed higher ratings for visual comfort and safety under red lighting. Surveys conducted earlier in the evening, with higher levels of predicted solar and measured horizontal illuminance, rated higher on visual comfort and safety, though these correlations were not as strong as the effect of lamp color. Streetlight ratings and support for lighting that protected natural resources were not contingent upon age or gender. Survey participants assessed red lighting as more protective of the environment. These results demonstrate that outdoor lighting designed to reduce ecological impacts can yield superior nocturnal experience for pedestrians.


Asunto(s)
Iluminación , Parques Recreativos , Humanos , Masculino , Femenino , Animales , Adulto , Persona de Mediana Edad , Adolescente , Adulto Joven , Color , Animales Salvajes , Encuestas y Cuestionarios , Conservación de los Recursos Naturales/métodos
5.
Am J Hum Genet ; 85(1): 25-39, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19576567

RESUMEN

A gene causing autosomal-recessive, nonsyndromic hearing loss, DFNB39, was previously mapped to an 18 Mb interval on chromosome 7q11.22-q21.12. We mapped an additional 40 consanguineous families segregating nonsyndromic hearing loss to the DFNB39 locus and refined the obligate interval to 1.2 Mb. The coding regions of all genes in this interval were sequenced, and no missense, nonsense, or frameshift mutations were found. We sequenced the noncoding sequences of genes, as well as noncoding genes, and found three mutations clustered in intron 4 and exon 5 in the hepatocyte growth factor gene (HGF). Two intron 4 deletions occur in a highly conserved sequence that is part of the 3' untranslated region of a previously undescribed short isoform of HGF. The third mutation is a silent substitution, and we demonstrate that it affects splicing in vitro. HGF is involved in a wide variety of signaling pathways in many different tissues, yet these putative regulatory mutations cause a surprisingly specific phenotype, which is nonsydromic hearing loss. Two mouse models of Hgf dysregulation, one in which an Hgf transgene is ubiquitously overexpressed and the other a conditional knockout that deletes Hgf from a limited number of tissues, including the cochlea, result in deafness. Overexpression of HGF is associated with progressive degeneration of outer hair cells in the cochlea, whereas cochlear deletion of Hgf is associated with more general dysplasia.


Asunto(s)
Pérdida Auditiva/genética , Factor de Crecimiento de Hepatocito/genética , Regiones no Traducidas 3'/genética , Empalme Alternativo , Animales , Cóclea/patología , Consanguinidad , Análisis Mutacional de ADN , Exones , Femenino , Pérdida Auditiva/patología , India , Intrones , Masculino , Ratones , Ratones Noqueados , Datos de Secuencia Molecular , Mutación , Pakistán , Linaje
6.
Dev Neurosci ; 32(2): 91-100, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20551645

RESUMEN

Prenatal alcohol exposure can lead to a wide range of adverse effects on a developing fetus. As a whole, these teratogenic outcomes are generally known as fetal alcohol spectrum disorders, the most severe of which is fetal alcohol syndrome (FAS). Clinically, children diagnosed with FAS vary greatly in their presentation of symptoms, likely due to the amount of alcohol and timing of exposure, as well as maternal and genetic influences. All these factors play a role in determining the mechanisms through which alcohol damages a developing brain, the details of which are still largely unknown. However, continuing research and recent developments have provided promising results that may lead to screening mechanisms and treatment therapies for children with FAS. Here we review the teratogenic effects of alcohol, strategies for detecting maternal alcohol consumption, identification of fetal biological markers, and prevention methods for FAS.


Asunto(s)
Consumo de Bebidas Alcohólicas/efectos adversos , Etanol/efectos adversos , Trastornos del Espectro Alcohólico Fetal/diagnóstico , Trastornos del Espectro Alcohólico Fetal/prevención & control , Efectos Tardíos de la Exposición Prenatal , Biomarcadores/metabolismo , Niño , Familia , Femenino , Trastornos del Espectro Alcohólico Fetal/patología , Trastornos del Espectro Alcohólico Fetal/fisiopatología , Humanos , Embarazo , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Efectos Tardíos de la Exposición Prenatal/prevención & control , Factores de Riesgo , Teratógenos
7.
Clin Cancer Res ; 14(20): 6478-86, 2008 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-18927287

RESUMEN

PURPOSE: Current therapy for lung cancer involves multimodality therapies. However, many patients are either refractory to therapy or develop drug resistance. KRAS and epidermal growth factor receptor (EGFR) mutations represent some of the most common mutations in lung cancer, and many studies have shown the importance of these mutations in both carcinogenesis and chemoresistance. Genetically engineered murine models of mutant EGFR and KRAS have been developed that more accurately recapitulate human lung cancer. Recently, using cell-based experiments, we showed that platinum-based drugs and the antidiabetic drug rosiglitazone (PPARgamma ligand) interact synergistically to reduce cancer cell and tumor growth. Here, we directly determined the efficacy of the PPARgamma/carboplatin combination in these more relevant models of drug resistant non-small cell lung cancer. EXPERIMENTAL DESIGN: Tumorigenesis was induced by activation of either mutant KRAS or EGFR. Mice then received either rosiglitazone or carboplatin monotherapy, or a combination of both drugs. Change in tumor burden, pathology, and evidence of apoptosis and cell growth were assessed. RESULTS: Tumor burden remained unchanged or increased in the mice after monotherapy with either rosiglitazone or carboplatin. In striking contrast, we observed significant tumor shrinkage in mice treated with these drugs in combination. Immunohistochemical analyses showed that this synergy was mediated via both increased apoptosis and decreased proliferation. Importantly, this synergy between carboplatin and rosiglitazone did not increase systemic toxicity. CONCLUSIONS: These data show that the PPARgamma ligand/carboplatin combination is a new therapy worthy of clinical investigation in lung cancers, including those cancers that show primary resistance to platinum therapy or acquired resistance to targeted therapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Carboplatino/uso terapéutico , Resistencia a Antineoplásicos/efectos de los fármacos , Hipoglucemiantes/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Tiazolidinedionas/uso terapéutico , Animales , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Quimioterapia Combinada , Receptores ErbB/fisiología , Genes ras/fisiología , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Imagen por Resonancia Magnética , Ratones , Ratones Transgénicos , PPAR gamma/agonistas , Inhibidores de Proteínas Quinasas/efectos adversos , Rosiglitazona , Uteroglobina/fisiología
8.
BMC Genomics ; 9: 282, 2008 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-18549478

RESUMEN

BACKGROUND: The lycophyte Selaginella moellendorffii is a vascular plant that diverged from the fern/seed plant lineage at least 400 million years ago. Although genomic information for S. moellendorffii is starting to be produced, little is known about basic aspects of its molecular biology. In order to provide the first glimpse to the epigenetic landscape of this early divergent vascular plant, we used the methylation filtration technique. Methylation filtration genomic libraries select unmethylated DNA clones due to the presence of the methylation-dependent restriction endonuclease McrBC in the bacterial host. RESULTS: We conducted a characterization of the DNA methylation patterns of the S. moellendorffii genome by sequencing a set of S. moellendorffii shotgun genomic clones, along with a set of methylation filtered clones. Chloroplast DNA, which is typically unmethylated, was enriched in the filtered library relative to the shotgun library, showing that there is DNA methylation in the extremely small S. moellendorffii genome. The filtered library also showed enrichment in expressed and gene-like sequences, while the highest-copy repeats were largely under-represented in this library. These results show that genes and repeats are differentially methylated in the S. moellendorffii genome, as occurs in other plants studied. CONCLUSION: Our results shed light on the genome methylation pattern in a member of a relatively unexplored plant lineage. The DNA methylation data reported here will help understanding the involvement of this epigenetic mark in fundamental biological processes, as well as the evolutionary aspects of epigenetics in land plants.


Asunto(s)
Metilación de ADN , ADN de Plantas/genética , Genoma de Planta , Secuencias Repetitivas de Ácidos Nucleicos , Selaginellaceae/genética , Composición de Base , Secuencia de Bases , Cartilla de ADN/genética , ADN de Cloroplastos/química , ADN de Cloroplastos/genética , ADN de Plantas/química , Epigénesis Genética , Etiquetas de Secuencia Expresada , Datos de Secuencia Molecular
9.
Appl Physiol Nutr Metab ; 40(11): 1157-62, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26513008

RESUMEN

High-intensity interval training (HIIT) is a time-efficient method of improving aerobic and anaerobic power and capacity. In most individuals, however, HIIT using modalities such as cycling, running, and rowing does not typically result in increased muscle strength, power, or endurance. The purpose of this study is to compare the physiological outcomes of traditional HIIT using rowing (Row-HIIT) with a novel multimodal HIIT (MM-HIIT) circuit incorporating multiple modalities, including strength exercises, within an interval. Twenty-eight recreationally active women (age 24.7 ± 5.4 years) completed 6 weeks of either Row-HIIT or MM-HIIT and were tested on multiple fitness parameters. MM-HIIT and Row-HIIT resulted in similar improvements (p < 0.05 for post hoc pre- vs. post-training increases for each group) in maximal aerobic power (7% vs. 5%), anaerobic threshold (13% vs. 12%), respiratory compensation threshold (7% vs. 5%), anaerobic power (15% vs. 12%), and anaerobic capacity (18% vs. 14%). The MM-HIIT group had significant (p < 0.01 for all) increases in squat (39%), press (27%), and deadlift (18%) strength, broad jump distance (6%), and squat endurance (280%), whereas the Row-HIIT group had no increase in any muscle performance variable (p values 0.33-0.90). Post-training, 1-repetition maximum (1RM) squat (64.2 ± 13.6 vs. 45.8 ± 16.2 kg, p = 0.02), 1RM press (33.2 ± 3.8 vs. 26.0 ± 9.6 kg, p = 0.01), and squat endurance (23.9 ± 12.3 vs. 10.2 ± 5.6 reps, p < 0.01) were greater in the MM-HIIT group than in the Row-HIIT group. MM-HIIT resulted in similar aerobic and anaerobic adaptations but greater muscle performance increases than Row-HIIT in recreationally active women.


Asunto(s)
Metabolismo Energético , Contracción Muscular , Fuerza Muscular , Músculo Esquelético/metabolismo , Resistencia Física , Entrenamiento de Fuerza/métodos , Adaptación Fisiológica , Adolescente , Adulto , Prueba de Esfuerzo , Femenino , Humanos , Estudios Longitudinales , Consumo de Oxígeno , Estudios Prospectivos , Factores de Tiempo , Adulto Joven
10.
Diabetes ; 63(10): 3266-78, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24947365

RESUMEN

Hepatic gluconeogenesis is crucial to maintain normal blood glucose during periods of nutrient deprivation. Gluconeogenesis is controlled at multiple levels by a variety of signal transduction and transcriptional pathways. However, dysregulation of these pathways leads to hyperglycemia and type 2 diabetes. While the effects of various signaling pathways on gluconeogenesis are well established, the downstream signaling events repressing gluconeogenic gene expression are not as well understood. The cell-cycle regulator cyclin D1 is expressed in the liver, despite the liver being a quiescent tissue. The most well-studied function of cyclin D1 is activation of cyclin-dependent kinase 4 (CDK4), promoting progression of the cell cycle. We show here a novel role for cyclin D1 as a regulator of gluconeogenic and oxidative phosphorylation (OxPhos) gene expression. In mice, fasting decreases liver cyclin D1 expression, while refeeding induces cyclin D1 expression. Inhibition of CDK4 enhances the gluconeogenic gene expression, whereas cyclin D1-mediated activation of CDK4 represses the gluconeogenic gene-expression program in vitro and in vivo. Importantly, we show that cyclin D1 represses gluconeogenesis and OxPhos in part via inhibition of peroxisome proliferator-activated receptor γ coactivator-1α (PGC1α) activity in a CDK4-dependent manner. Indeed, we demonstrate that PGC1α is novel cyclin D1/CDK4 substrate. These studies reveal a novel role for cyclin D1 on metabolism via PGC1α and reveal a potential link between cell-cycle regulation and metabolic control of glucose homeostasis.


Asunto(s)
Ciclina D1/metabolismo , Quinasa 4 Dependiente de la Ciclina/metabolismo , Gluconeogénesis/genética , Hígado/metabolismo , Factores de Transcripción/metabolismo , Animales , Células COS , Chlorocebus aethiops , Ciclina D1/genética , Quinasa 4 Dependiente de la Ciclina/genética , Ingestión de Alimentos/fisiología , Ayuno/metabolismo , Glucosa/metabolismo , Células Hep G2 , Homeostasis/fisiología , Humanos , Ratones , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma , Factores de Transcripción/genética
11.
J Mol Evol ; 65(1): 1-11, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17646893

RESUMEN

Chlamydomonas reinhardtii, Volvox carteri, and their relatives in the family Volvocaceae provide an excellent opportunity for studying how multicellular organisms with differentiated cell types evolved from unicellular ancestors. While C. reinhardtii is unicellular, V. carteri is multicellular with two cell types, one of which resembles C. reinhardtii cytologically but is terminally differentiated. Maintenance of this "somatic cell" fate is controlled by RegA, a putative transcription factor. We recently showed that RegA shares a conserved region with several predicted V. carteri and C. reinhardtii proteins and that this region, the VARL domain, is likely to include a DNA-binding SAND domain. As the next step toward understanding the evolutionary origins of the regA gene, we analyzed the genome sequences of C. reinhardtii and V. carteri to identify additional genes with the potential to encode VARL domain proteins. Here we report that the VARL gene family, which consists of 12 members in C. reinhardtii and 14 in V. carteri, has experienced a complex evolutionary history in which members of the family have been both gained and lost over time, although several pairs of potentially orthologous genes can still be identified. We find that regA is part of a tandem array of four VARL genes in V. carteri but that a similar array is absent in C. reinhardtii. Most importantly, our phylogenetic analysis suggests that a proto-regA gene was present in a common unicellular ancestor of V. carteri and C. reinhardtii and that this gene was lost in the latter lineage.


Asunto(s)
Proteínas Algáceas/genética , Chlamydomonas reinhardtii/genética , Evolución Molecular , Familia de Multigenes , Volvox/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Bases de Datos Genéticas , Datos de Secuencia Molecular , Filogenia , Estructura Terciaria de Proteína/genética , Alineación de Secuencia
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