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1.
Front Plant Sci ; 14: 1012718, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36743508

RESUMO

Plant-to-plant variation (interplant variation) may play an important role in determining individual plant and whole canopy performance, where interplant variation in architecture and photosynthesis traits has direct effects on light absorption and photosynthesis. We aimed to quantify the importance of observed interplant variation on both whole-plant and canopy light absorption and photosynthesis. Plant architecture was measured in two experiments with fruiting tomato crops (Solanum lycopersicum) grown in glasshouses in the Netherlands, in week 16 (Exp. 1) or week 19 (Exp. 2) after transplanting. Experiment 1 included four cultivars grown under three supplementary lighting treatments, and Experiment 2 included two different row orientations. Measured interplant variations of the architectural traits, namely, internode length, leaf area, petiole angle, and leaflet angle, as well as literature data on the interplant variation of the photosynthesis traits alpha, J max28, and V cmax28, were incorporated in a static functional-structural plant model (FSPM). The FSPM was used to analyze light absorption and net photosynthesis of whole plants in response to interplant variation in architectural and photosynthesis traits. Depending on the trait, introducing interplant variation in architecture and photosynthesis traits in a functional-structural plant model did not affect or negatively affected canopy light absorption and net photosynthesis compared with the reference model without interplant variation. Introducing interplant variation of architectural and photosynthesis traits in FSPM results in a more realistic simulation of variation of plants within a canopy. Furthermore, it can improve the accuracy of simulation of canopy light interception and photosynthesis although these effects at the canopy level are relatively small (<4% for light absorption and<7% for net photosynthesis).

2.
Hum Genome Var ; 8(1): 17, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-33963180

RESUMO

An 11-year-old Korean boy presented with short stature, hip dysplasia, radial head dislocation, carpal coalition, genu valgum, and fixed patellar dislocation and was clinically diagnosed with Steel syndrome. Scrutinizing the trio whole-exome sequencing data revealed novel compound heterozygous mutations of COL27A1 (c.[4229_4233dup]; [3718_5436del], p.[Gly1412Argfs*157];[Gly1240_Lys1812del]) in the proband, which were inherited from heterozygous parents. The maternal mutation was a large deletion encompassing exons 38-60, which was challenging to detect.

4.
Skeletal Radiol ; 46(9): 1297-1300, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28601949

RESUMO

We report transient proximal and distal femoral metaphyseal striations that have not previously been described in autosomal dominant brachyolmia. The pelvis/hip radiograph of a 13-year-old boy demonstrated bilaterally symmetrical proximal femoral metaphyseal vertical striations. Additional vertical striations were also observed at the distal femur and proximal tibia metaphysis. Radiography of the thoracolumbar spine demonstrated platyspondyly with irregular endplates and overfaced pedicles. TRPV4 mutations were confirmed in this patient. Similar proximal femoral metaphyseal vertical striations were noted in the patient's sibling. Those streaks disappeared on the follow-up radiographs, and we considered it a unique radiologic finding transiently observed in autosomal dominant brachyolmia.


Assuntos
Osteocondrodisplasias/diagnóstico por imagem , Adolescente , Criança , Diagnóstico Diferencial , Humanos , Masculino
5.
Eur J Med Genet ; 60(8): 411-415, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28528193

RESUMO

Osteogenesis imperfecta (OI) is a heritable skeletal disorder characterized by bone fragility and low bone mass. Recently, loss-of-function mutations of WNT1 have been reported to be causative in OI or osteoporosis. We report an OI patient with novel compound heterozygous WNT1 missense mutations, p.Glu123Asp and p.Cys153Gly. Both mutations are found in the exon 3, and the p.Glu123Asp is the most proximal N-terminus missense mutation among the reported WNT1 missense mutations in OI patients. In vitro functional analysis reveals that while expression of wildtype WNT1 stimulates canonical WNT1-mediated ß-catenin signaling, that of individual WNT1 mutant fails to do so, indicative of the pathogenic nature of the WNT1 variants. Although the pathogenic mechanism of WNT1 defects in OI has yet to be uncovered, these findings further contribute to the implications and importance of functional relevance of WNT1 in skeletal disorders.


Assuntos
Mutação de Sentido Incorreto , Osteogênese Imperfeita/genética , Proteína Wnt1/genética , Adulto , Feminino , Genes Recessivos , Células HEK293 , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Osteogênese Imperfeita/diagnóstico , Linhagem , Proteína Wnt1/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
6.
J Child Neurol ; 32(2): 237-242, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27777327

RESUMO

Wiedemann-Steiner syndrome is a rare genetic disorder characterized by short stature, hairy elbows, facial dysmorphism, and developmental delay. It can also be accompanied by musculoskeletal anomalies such as muscular hypotonia and small hands and feet. Mutations in the KMT2A gene have only recently been identified as the cause of Wiedemann-Steiner syndrome; therefore, only 16 patients from 15 families have been described, and new phenotypic features continue to be added. In this report, we describe 2 newly identified patients with Wiedemann-Steiner syndrome who presented with variable severity. One girl exhibited developmental dysplasia of the hip and fibromatosis colli accompanied by other clinical features, including facial dysmorphism, hypertrichosis, patent ductus arteriosus, growth retardation, and borderline intellectual disability. The other patient, a boy, showed severe developmental retardation with automatic self-mutilation, facial dysmorphism, and hypertrichosis at a later age. Exome sequencing analysis of these patients and their parents revealed a de novo nonsense mutation, p.Gln1978*, of KMT2A in the former, and a missense mutation, p.Gly1168Asp, in the latter, which molecularly confirmed the diagnosis of Wiedemann-Steiner syndrome.


Assuntos
Anormalidades Múltiplas/genética , Deficiências do Desenvolvimento/genética , Luxação Congênita de Quadril/genética , Histona-Lisina N-Metiltransferase/genética , Anormalidades Musculoesqueléticas/genética , Mutação , Proteína de Leucina Linfoide-Mieloide/genética , Criança , Pré-Escolar , Face/anormalidades , Feminino , Antebraço/anormalidades , Deformidades Congênitas da Mão/genética , Humanos , Hipertricose/genética , Masculino , Síndrome
7.
Orphanet J Rare Dis ; 11: 1, 2016 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-26728142

RESUMO

Ischiospinal dysostosis (ISD) is a polytopic dysostosis characterized by ischial hypoplasia, multiple segmental anomalies of the cervicothoracic spine, hypoplasia of the lumbrosacral spine and occasionally associated with nephroblastomatosis. ISD is similar to, but milder than the lethal/semilethal condition termed diaphanospondylodysostosis (DSD), which is associated with homozygous or compound heterozygous mutations of bone morphogenetic protein-binding endothelial regulator protein (BMPER) gene. Here we report for the first time biallelic BMPER mutations in two patients with ISD, neither of whom had renal abnormalities. Our data supports and further extends the phenotypic variability of BMPER-related skeletal disorders.


Assuntos
Proteínas de Transporte/genética , Anormalidades Craniofaciais/diagnóstico , Disostoses/diagnóstico , Disostoses/genética , Costelas/anormalidades , Coluna Vertebral/anormalidades , Adulto , Pré-Escolar , Anormalidades Craniofaciais/genética , Feminino , Humanos , Masculino , Mutação , Adulto Jovem
8.
Obstet Gynecol Sci ; 57(1): 66-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24596820

RESUMO

Physiologic pituitary enlargement is common during normal pregnancy. However, symptoms such as diplopia, blurred vision and headache resulting from physiologic pituitary enlargement are very rare during pregnancy. A 39-year-old woman complained of sudden diplopia and left eye ptosis at 33th weeks of gestation. An magnetic resonance imaging (MRI) demonstrated the pituitary enlargement compressing the optic chiasm. Notwithstanding the medication of bromocriptine, her symptoms did not regress during pregnancy. At 5 months after delivery, her symptoms dramatically resolved without any surgery, and her visual acuity was normalized. Her MRI scan also revealed more decreased size of pituitary gland compared to antenatal MRI. We report a case of visual loss due to the physiologic pituitary enlargement of nonfunctioning adenoma during pregnancy, which regressed spontaneously after delivery without any surgery.

9.
Photochem Photobiol ; 89(2): 326-31, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23094959

RESUMO

Near-infrared heptamethine cyanine dye is functionalized with pyrazole derivatives at the meso-position to induce pH-dependent photophysical properties. The presence of pyrazole unsubstituted at (1) N-position is essential to induce pH-dependent fluorescence intensity and lifetime changes in these dyes. Replacement of meso-chloro group of cyanine dye IR820 with (1) N-unsubstituted pyrazole resulted in the pH-dependent fluorescence lifetime changes from 0.93 ns in neutral media to 1.27 ns in acidic media in DMSO. Time-resolved emission spectra (TRES) revealed that at lower pH, the pyrazole consists of fluorophores with two distinct lifetimes, which cor-responds to pH-sensitive and non-pH-sensitive species. In contrast, (1) N-substituted pyrazoles do not exhibit pH response, suggesting excited state electron transfer as the mechanism of pH-dependent fluorescence lifetime sensitivity for this class of compounds.


Assuntos
Carbocianinas/química , Elétrons , Corantes Fluorescentes/química , Verde de Indocianina/análogos & derivados , Pirazóis/química , Dimetil Sulfóxido , Fluorescência , Concentração de Íons de Hidrogênio , Verde de Indocianina/química , Espectrometria de Fluorescência , Espectroscopia de Luz Próxima ao Infravermelho
10.
Mol Cell Biol ; 33(4): 763-72, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23230266

RESUMO

Centromeres, the sites of spindle attachment during mitosis and meiosis, are located in specific positions in the human genome, normally coincident with diverse subsets of alpha satellite DNA. While there is strong evidence supporting the association of some subfamilies of alpha satellite with centromere function, the basis for establishing whether a given alpha satellite sequence is or is not designated a functional centromere is unknown, and attempts to understand the role of particular sequence features in establishing centromere identity have been limited by the near identity and repetitive nature of satellite sequences. Utilizing a broadly applicable experimental approach to test sequence competency for centromere specification, we have carried out a genomic and epigenetic functional analysis of endogenous human centromere sequences available in the current human genome assembly. The data support a model in which functionally competent sequences confer an opportunity for centromere specification, integrating genomic and epigenetic signals and promoting the concept of context-dependent centromere inheritance.


Assuntos
Centrômero/genética , DNA Satélite/genética , Genoma Humano , Autoantígenos/genética , Sequência de Bases , Proteína Centromérica A , Proteínas Cromossômicas não Histona/genética , Cromossomos Artificiais/genética , Bases de Dados Genéticas , Humanos , Dados de Sequência Molecular
11.
Korean J Pathol ; 46(1): 61-7, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23109980

RESUMO

BACKGROUND: Papillary thyroid carcinoma (PTC) of the thyroid is the most common endocrine malignancy. High prevalence of an activating point mutation of BRAF gene, BRAF(V600E), has been reported in PTC. We assessed the efficiency of peptide nucleic acid clamp real-time polymerase chain reaction (PNAcqPCR) for the detection of BRAF(V600E) mutation in PTC in comparison with direct sequencing (DS). METHODS: A total of 265 thyroid lesions including 200 PTCs, 5 follicular carcinomas, 60 benign lesions and 10 normal thyroid tissues were tested for BRAF(V600E) mutation by PNAcqPCR and DS. RESULTS: The sensitivity and accuracy of the PNAcqPCR method were both higher than those of DS for the detection of the BRAF(V600E) mutation. In clinical samples, 89% of PTCs harbored the BRAF(V600E) mutation, whereas 5 follicular carcinomas, 50 benign lesions and 10 normal thyroid tissues lacked the mutation. The mutation was associated with aggressive clinical behaviors as extrathyroid invasion (p=0.015), lymph node metastasis (p=0.002) and multiple tumor numbers (p=0.016) with statistical significance. CONCLUSIONS: The PNAcqPCR method is efficiently applicable for the detection of the BRAF(V600E) mutation in PTCs in a clinical setting.

12.
J Am Chem Soc ; 134(10): 4545-8, 2012 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-22360301

RESUMO

Modulation of the fluorescence lifetime (FLT) of CdTeSe/ZnS quantum dots (QDs) by near-IR (NIR) organic chromophores represents a new strategy for generating reproducible pH-sensing nanomaterials. The hybrid construct transfers the pH sensitivity of photolabile NIR cyanine dyes to highly emissive and long-lifetime pH-insensitive QDs, thereby inducing a reproducible FLT change from 29 ns at pH >7 to 12 ns at pH <5. This approach provides an unparalleled large dynamic FLT range for pH sensing at NIR wavelengths.


Assuntos
Corantes Fluorescentes/química , Concentração de Íons de Hidrogênio , Pontos Quânticos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Fluorescência , Transferência Ressonante de Energia de Fluorescência , Microscopia Eletrônica de Transmissão , Espectrofotometria Ultravioleta
13.
Bioconjug Chem ; 23(3): 656-63, 2012 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-22309692

RESUMO

We report a novel activatable NIR fluorescent probe for in vivo detection of cancer-related matrix metalloproteinase (MMP) activity. The probe is based on a triple-helical peptide substrate (THP) with high specificity for MMP-2 and MMP-9 relative to other members of the MMP family. MMP-2 and MMP-9 (also known as gelatinases) are specifically associated with cancer cell invasion and cancer-related angiogenesis. At the center of each 5 kDa peptide strand is a gelatinase sensitive sequence flanked by 2 Lys residues conjugated with NIR fluorescent dyes. Upon self-assembly of the triple-helical structure, the 3 peptide chains intertwine, bringing the fluorophores into close proximity and reducing fluorescence via quenching. Upon enzymatic cleavage of the triple-helical peptide, 6 labeled peptide chains are released, resulting in an amplified fluorescent signal. The fluorescence yield of the probe increases 3.8-fold upon activation. Kinetic analysis showed a rate of LS276-THP hydrolysis by MMP-2 (k(cat)/K(M) = 30,000 s(-1) M(-1)) similar to that of MMP-2 catalysis of an analogous fluorogenic THP. Administration of LS276-THP to mice bearing a human fibrosarcoma xenografted tumor resulted in a tumor fluorescence signal more than 5-fold greater than that of muscle. This signal enhancement was reduced by treatment with the MMP inhibitor Ilomostat, indicating that the observed tumor fluorescence was indeed enzyme mediated. These results are the first to demonstrate that triple-helical peptides are suitable for highly specific in vivo detection of tumor-related MMP-2 and MMP-9 activity.


Assuntos
Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Peptídeos/metabolismo , Corantes Fluorescentes , Humanos , Imuno-Histoquímica , Cinética , Proteólise , Espectroscopia de Luz Próxima ao Infravermelho
14.
J Nanosci Nanotechnol ; 11(8): 7382-5, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22103201

RESUMO

The Nanolayered TiO2 photocatalysts were prepared by thermal treatment of metallic titanium chips. Photocatalytic activity for methyl ethyl ketone (MEK) and toluene was investigated using a closed circulating system. The photocatalysts were characterized by SEM and XRD. Surface of the Ti chips changed to be rough with increase of treatment temperature, and severe oxidation over 900 degrees C resulted in TiO2 powder. Uniform TiO2 nanolayer was formed as a rutile type on the metallic chip. Photocatalytic decomposition of MEK over the TiO2 photocatalysts occurred efficiently by UV-C irradiation. The maximum activity for MEK was obtained over Ti Chip treated at 700 degrees C. It was known that the prepared photocatalyts could be applied to remove various VOCs.

15.
J Phys Chem B ; 115(39): 11530-5, 2011 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-21866928

RESUMO

Two-photon (2P) optical properties of cyanine dyes were evaluated using a 2P fluorescence spectrophotometer with 1.55 µm excitation. We report the 2P characteristics of common NIR polymethine dyes, including their 2P action cross sections and the 2P excited fluorescence lifetime. One of the dyes, DTTC, showed the highest 2P action cross-section (∼103 ± 19 GM) and relatively high 2P excited fluorescence lifetime and can be used as a scaffold for the synthesis of 2P molecular imaging probes. The 2P action cross-section of DTTC and the lifetime were also highly sensitive to the solvent polarity, providing other additional parameters for its use in optical imaging and the mechanism for probing environmental factors. Overall, this study demonstrated the quantitative measurement of 2P properties of NIR dyes and established the foundation for designing molecular probes for 2P imaging applications in the NIR region.


Assuntos
Corantes/química , Animais , Rim/anatomia & histologia , Camundongos , Microscopia de Fluorescência , Fótons , Teoria Quântica , Solventes/química
16.
Genome Biol Evol ; 3: 1136-49, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21828373

RESUMO

Centromeric regions in many complex eukaryotic species contain highly repetitive satellite DNAs. Despite the diversity of centromeric DNA sequences among species, the functional centromeres in all species studied to date are marked by CENP-A, a centromere-specific histone H3 variant. Although it is well established that families of multimeric higher-order alpha satellite are conserved at the centromeres of human and great ape chromosomes and that diverged monomeric alpha satellite is found in old and new world monkey genomes, little is known about the organization, function, and evolution of centromeric sequences in more distant primates, including lemurs. Aye-Aye (Daubentonia madagascariensis) is a basal primate and is located at a key position in the evolutionary tree to study centromeric satellite transitions in primate genomes. Using the approach of chromatin immunoprecipitation with antibodies directed to CENP-A, we have identified two satellite families, Daubentonia madagascariensis Aye-Aye 1 (DMA1) and Daubentonia madagascariensis Aye-Aye 2 (DMA2), related to each other but unrelated in sequence to alpha satellite or any other previously described primate or mammalian satellite DNA families. Here, we describe the initial genomic and phylogenetic organization of DMA1 and DMA2 and present evidence of higher-order repeats in Aye-Aye centromeric domains, providing an opportunity to study the emergence of chromosome-specific modes of satellite DNA evolution in primate genomes.


Assuntos
Autoantígenos/genética , Proteínas Cromossômicas não Histona/genética , DNA Satélite/genética , Evolução Molecular , Genoma , Família Multigênica , Primatas/genética , Animais , Sequência de Bases , Linhagem Celular , Centrômero/genética , Proteína Centromérica A , Feminino , Humanos , Masculino , Dados de Sequência Molecular , Filogenia , Primatas/classificação
17.
J Clin Biochem Nutr ; 49(1): 62-6, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21765609

RESUMO

This study aimed to examine the association of dietary vitamin intakes with plasma pro-inflammatory cytokine levels in Korean heart failure patients. Stable outpatients with heart failure were recruited and finally 91 patients were included. Dietary intakes were estimated by a developed semi-quantitative food frequency questionnaire. The simultaneous measurement of 17 cytokines was performed along with analysis of plasma C-reactive protein. Plasma C-reactive protein levels significantly correlated with dietary intakes of vitamin C (r = -0.30, p<0.005), ß-carotene (r = -0.23, p<0.05), and folate (r = -0.31, p<0.005). However, these associations were no longer significant after adjusting for traditional risk factors for heart failure. On the other hand, plasma levels of monocyte chemoattractant protein-1 significantly correlated with dietary folate intake (r = -0.31, p<0.001), and plasma interleukin-8 levels significantly correlated with dietary intakes of vitamin C (r = -0.38, p<0.001), ß-carotene (r = -0.42, p<0.001), and folate (r = -0.38, p<0.001) after the adjustment. Dietary folate intake was found as a primary influencing factor on plasma levels of monocyte chemoattractant protein-1 (p<0.005, R(2) = 0.20) and interleukin-8 (p<0.001, R(2) = 0.32) through a stepwise multiple linear regression analysis. Dietary folate intake was significantly associated with plasma levels of monocyte chemoattractant protein-1 and interleukin-8 which indicates dietary folate may have a potentially beneficial role in the prevention and treatment of heart failure.

18.
Nutr Res Pract ; 5(1): 28-33, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21487493

RESUMO

Limited information from human studies indicates that dietary quercetin supplementation influences blood lipid profiles, glycemic response, and inflammatory status, collectively termed cardiometabolic risks. We tested the hypothesis that quercetin-rich supplementation, derived from onion peel extract, improves cardiometabolic risk components in healthy male smokers in a randomized, double blinded, placebo-controlled parallel design. Randomly assigned subjects were instructed to take either the placebo (n = 43) or 100 mg quercetin capsules each day (n = 49) for 10 weeks. Anthropometric parameters and blood pressure were measured, and blood lipids, glucose, interleukin-6, and soluble vascular cell adhesion molecule-1 (sVCAM-1) were determined at baseline and after 10 weeks of quercetin supplementation. Quercetin-rich supplementation significantly reduced serum concentrations of total cholesterol (P < 0.05) and LDL-cholesterol (P < 0.01), whereas these effects were not shown in the placebo group. Furthermore, significant increases were observed in serum concentrations of HDL-cholesterol both in the placebo (P < 0.005) and quercetin-rich supplementation group (P < 0.001); however, changes in HDL-cholesterol were significantly greater in subjects receiving quercetin-rich supplementation than the placebo. Both systolic (P < 0.05) and diastolic blood pressure (P < 0.01) decreased significantly in the quercetin-rich supplementation group. Glucose concentrations decreased significantly after 10 weeks of quercetin-rich supplementation (P < 0.05). In contrast, no effects of quercetin-rich supplementation were observed for the inflammatory markers-IL-6 and sVCAM-1. Daily quercetin-rich supplementation from onion peel extract improved blood lipid profiles, glucose, and blood pressure, suggesting a beneficial role for quercetin as a preventive measure against cardiovascular risk.

19.
Bioconjug Chem ; 22(4): 777-84, 2011 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-21388195

RESUMO

Highly tumor selective near-infrared (NIR) pH-activatable probe was developed by conjugating pH-sensitive cyanine dye to a cyclic arginine-glycine-aspartic acid (cRGD) peptide targeting α(v)ß(3) integrin (ABIR), a protein that is highly overexpressed in endothelial cells during tumor angiogenesis. The NIR pH-sensitive dye used to construct the probe exhibits high spectral sensitivity with pH changes. It has negligible fluorescence above pH 6 but becomes highly fluorescent below pH 5, with a pK(a) of 4.7. This probe is ideal for imaging acidic cell organelles such as tumor lysosomes or late endosomes. Cell microscopy data demonstrate that binding of the cRGD probe to ABIR facilitated the endocytosis-mediated lysosomal accumulation and subsequent fluorescence enhancement of the NIR pH-activatable dye in tumor cells (MDA-MB-435 and 4T1/luc). A similar fluorescence enhancement mechanism was observed in vivo, where the tumors were evident within 4 h post injection. Moreover, lung metastases were also visualized in an orthotopic tumor mouse model using this probe, which was further confirmed by histologic analysis. These results demonstrate the potential of using the new integrin-targeted pH-sensitive probe for the detection of primary and metastatic cancer.


Assuntos
Neoplasias da Mama/diagnóstico , Diagnóstico por Imagem , Corantes Fluorescentes/química , Neoplasias da Mama/metabolismo , Neoplasias da Mama/secundário , Células Endoteliais/metabolismo , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/farmacocinética , Humanos , Concentração de Íons de Hidrogênio , Integrina alfaVbeta3/análise , Integrina alfaVbeta3/biossíntese , Microscopia Confocal , Estrutura Molecular , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacocinética , Sensibilidade e Especificidade , Espectroscopia de Luz Próxima ao Infravermelho , Distribuição Tecidual , Células Tumorais Cultivadas
20.
Biochemistry ; 50(13): 2691-700, 2011 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-21329363

RESUMO

We demonstrate that the structure of carbocyanine dyes, which are commonly used to label small peptides for molecular imaging and not the bound peptide, controls the rate of extravasation from blood vessels to tissue. By examining several near-infrared (NIR) carbocyanine fluorophores, we demonstrate a quantitative correlation between the binding of a dye to albumin, a model plasma protein, and the rate of extravasation of the probe into tissue. Binding of the dyes was measured by fluorescence quenching of the tryptophans in albumin and was found to be inversely proportional to the rate of extravasation. The rate of extravasation, determined by kurtosis from longitudinal imaging studies using rodent ear models, provided a basis for quantitative measurements. Structure-activity studies aimed at evaluating a representative library of NIR fluorescent cyanine probes showed that hydrophilic dyes with binding constants several orders of magnitude lower than their hydrophobic counterparts have much faster extravasation rate, establishing a foundation for rational probe design. The correlation provides a guideline for dye selection in optical imaging and a method to verify if a certain dye is optimal for a specific molecular imaging application.


Assuntos
Carbocianinas/metabolismo , Corantes Fluorescentes/metabolismo , Imagem Molecular/métodos , Sondas Moleculares/metabolismo , Oligopeptídeos/metabolismo , Animais , Carbocianinas/química , Carbocianinas/farmacocinética , Extravasamento de Materiais Terapêuticos e Diagnósticos , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacocinética , Interações Hidrofóbicas e Hidrofílicas , Cinética , Camundongos , Sondas Moleculares/química , Sondas Moleculares/farmacocinética , Oligopeptídeos/química , Oligopeptídeos/farmacocinética , Soroalbumina Bovina/metabolismo , Relação Estrutura-Atividade
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