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1.
Int J Mol Sci ; 18(12)2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29194406

RESUMO

Mucopolysaccharidosis III type A (MPS IIIA; Sanfilippo syndrome), a genetic lysosomal disorder causing a deficiency of heparan N-sulfatase (HNS), leads to progressive cognitive decline from an early age. An effective enzyme replacement therapy (ERT) for MPS IIIA requires central nervous system (CNS) biodistribution. Recombinant human heparan N-sulfatase (rhHNS), an investigatory ERT for MPS IIIA, has been formulated for intrathecal (IT) administration since intravenous (IV) administration cannot cross the blood brain barrier (BBB) in sufficient amounts to have a therapeutic effect. In this study, systemic and CNS distribution of rhHNS in cynomolgus monkeys following IV and IT administration was evaluated by quantitation of rhHNS in serum, cerebral spinal fluid (CSF) and various tissues, and positron emission tomography (PET) imaging of live animals. Following IV administration, rhHNS levels were low to non-detectable in the CSF, and systemic clearance was rapid (≤2 h). With IT administration, rhHNS was observable in CNS tissues in ≤1 h, with varying Tmax (1-24 h). Appreciable systemic distribution was observed up to 7 days. This provides evidence that in this animal model, intrathecal administration of rhHNS delivers the replacement enzyme to therapeutically relevant tissues for the treatment of Sanfilippo Syndrome type A. Penetration into grey matter and cortex was 3-4 times greater than concentrations in white matter and deeper parenchymal regions, suggesting some limitations of this ERT strategy.


Assuntos
Sistema Nervoso Central/química , Sulfatases/administração & dosagem , Sulfatases/farmacocinética , Administração Intravenosa , Animais , Sistema Nervoso Central/diagnóstico por imagem , Modelos Animais de Doenças , Humanos , Injeções Espinhais , Macaca fascicularis , Masculino , Mucopolissacaridose III/tratamento farmacológico , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacocinética , Distribuição Tecidual
2.
Psychometrika ; 88(3): 1032-1055, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37217762

RESUMO

In the current paper, we review existing tools for solving variable selection problems in psychology. Modern regularization methods such as lasso regression have recently been introduced in the field and are incorporated into popular methodologies, such as network analysis. However, several recognized limitations of lasso regularization may limit its suitability for psychological research. In this paper, we compare the properties of lasso approaches used for variable selection to Bayesian variable selection approaches. In particular we highlight advantages of stochastic search variable selection (SSVS), that make it well suited for variable selection applications in psychology. We demonstrate these advantages and contrast SSVS with lasso type penalization in an application to predict depression symptoms in a large sample and an accompanying simulation study. We investigate the effects of sample size, effect size, and patterns of correlation among predictors on rates of correct and false inclusion and bias in the estimates. SSVS as investigated here is reasonably computationally efficient and powerful to detect moderate effects in small sample sizes (or small effects in moderate sample sizes), while protecting against false inclusion and without over-penalizing true effects. We recommend SSVS as a flexible framework that is well-suited for the field, discuss limitations, and suggest directions for future development.


Assuntos
Teorema de Bayes , Simulação por Computador , Psicometria , Humanos
3.
Evol Psychol ; 20(3): 14747049221110603, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35791506

RESUMO

What features of people's childhood environments go on to shape their prosocial behavior during adulthood? Past studies linking childhood environment to adult prosocial behavior have focused primarily on adverse features, thereby neglecting the possible influence of exposure to enriched environments (e.g., access to material resources, experiences with rich cooperative relationships, and interactions with morally exemplary role models). Here, we expand the investigation of childhood environmental quality to include consideration of enriching childhood experiences and their relation to adult prosociality. In two cross-sectional studies, we found promising evidence that enriched childhood environments are associated with adult moral behavior. In study 1 (N = 1,084 MTurk workers), we adapted an existing measure of enriched childhood environmental quality for retrospective recall of childhood experiences and found that subjects' recollections of their enriched childhood experiences are distinct from their recollections of adverse childhood experiences. In Study 2 (N = 2,208 MTurk workers), we found that a formative composite of subjects' recollections of enriched childhood experiences is positively associated with a variety of morally relevant traits in adulthood, including agreeableness, honesty-humility, altruism, endorsement of the principle of care, empathic responding to the plights of needy others, and charitable donations in an experimental setting, and that these associations held after controlling for childhood environmental adversity, childhood socioeconomic status, sex, and age. We also found evidence suggesting that some, but not all, of the relationship between enrichment and adult prosociality can be explained by a shared genetic correlation. We include a new seven-item measure as an appendix.


Assuntos
Altruísmo , Personalidade , Adulto , Estudos Transversais , Humanos , Estudos Retrospectivos , Autorrelato
4.
Curr Opin Psychol ; 44: 275-280, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34801844

RESUMO

We review the logic of an evolutionary perspective on forgiveness, highlighting how insight into the likely function of forgiveness - solving adaptive problems related to acquiring and maintaining social relationships - has productively guided research and theory. A combination of experimental, longitudinal, cross-sectional, and cross-cultural evidence supports the claim that victims' perceptions of harmdoers' relationship value and exploitation risk causally influence whether or not victims forgive harmdoers. We also review the nascent literature on the topic of intergroup forgiveness and consider how the concepts associated with interpersonal forgiveness, such as apologies, relationship value, and exploitation risk, might help us understand forgiveness between groups, cultures, and societies. Finally, we explore the intersection of evolutionary and cultural perspectives on forgiveness, and consider how concepts from these two research traditions might be integrated to help us understand forgiveness even better.


Assuntos
Perdão , Estudos Transversais , Humanos , Relações Interpessoais
5.
J Pers Soc Psychol ; 120(6): 1621-1633, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32463272

RESUMO

Recent theorizing suggests that religious people's moral convictions are quite strategic (albeit unconsciously so), designed to make their worlds more amenable to their favored approaches to solving life's basic challenges. In a meta-analysis of 5 experiments and a preregistered replication, we find that religious identity places a sex premium on moral judgments, causing people to judge violations of conventional sexual morality as particularly objectionable. The sex premium is especially strong among highly religious people, and applies to both legal and illegal acts. Religion's influence on moral reasoning emphasizes conventional sexual norms, and may reflect the strategic projects to which religion has been applied throughout history. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Assuntos
Julgamento , Princípios Morais , Motivação , Religião e Psicologia , Comportamento Sexual/psicologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
6.
J Pers Soc Psychol ; 119(4): 861-880, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31815500

RESUMO

Researchers commonly conceptualize forgiveness as a rich complex of psychological changes involving attitudes, emotions, and behaviors. Psychometric work with the measures developed to capture this conceptual richness, however, often points to a simpler picture of the psychological dimensions in which forgiveness takes place. In an effort to better unite forgiveness theory and measurement, we evaluate several psychometric models for common measures of forgiveness. In doing so, we study people from the United States and Japan to understand forgiveness in both nonclose and close relationships. In addition, we assess the predictive utility of these models for several behavioral outcomes that traditionally have been linked to forgiveness motives. Finally, we use the methods of item response theory, which place person abilities and item responses on the same metric and, thus, help us draw psychological inferences from the ordering of item difficulties. Our results highlight models based on correlated factors models and bifactor (S-1) models. The bifactor (S-1) model evinced particular utility: Its general factor consistently predicts variation in relevant criterion measures, including 4 different experimental economic games (when played with a transgressor), and also suffuses a second self-report measure of forgiveness. Moreover, the general factor of the bifactor (S-1) model identifies a single psychological dimension that runs from hostility to friendliness while also pointing to other sources of variance that may be conceived of as method factors. Taken together, these results suggest that forgiveness can be usefully conceptualized as prosocial change along a single attitudinal continuum that ranges from hostility to friendliness. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Assuntos
Perdão , Hostilidade , Relações Interpessoais , Adulto , Atitude , Emoções , Feminino , Humanos , Japão , Masculino , Motivação , Psicometria , Estados Unidos
7.
Oligonucleotides ; 16(4): 337-51, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17155909

RESUMO

Aptamers are short oligonucleotides that fold into well-defined three-dimensional architectures thereby enabling specific binding to molecular targets such as proteins. To be successful as a novel therapeutic modality, it is important for aptamers to not only bind their targets with high specificity and affinity, but also to exhibit favorable properties with respect to in vivo stability, cost-effective synthesis, and tolerability (i.e., safety). We describe methods for generating aptamers comprising 2 - deoxy purines and 2 -O-methyl pyrimidines (dRmY) that broadly satisfy many of these additional constraints. Conditions under which dRmY transcripts can be efficiently synthesized using mutant T7 RNA polymerases have been identified and used to generate large libraries from which dRmY aptamers to multiple target proteins, including interleukin (IL)-23 and thrombin, have been successfully discovered using the SELEX process. dRmY aptamers are shown to be highly nuclease-resistant, long-lived in vivo, efficiently synthesized, and capable of binding protein targets in a manner that inhibits their biologic activity with K(D) values in the low nM range. We believe that dRmY aptamers have considerable potential as a new class of therapeutic aptamers.


Assuntos
Aptâmeros de Nucleotídeos/uso terapêutico , Animais , Aptâmeros de Nucleotídeos/síntese química , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/genética , Sequência de Bases , RNA Polimerases Dirigidas por DNA/genética , RNA Polimerases Dirigidas por DNA/metabolismo , Estabilidade de Medicamentos , Humanos , Camundongos , Estrutura Molecular , Ligação Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Técnica de Seleção de Aptâmeros , Transcrição Gênica , Proteínas Virais/genética , Proteínas Virais/metabolismo
8.
Chem Biol ; 12(1): 25-33, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15664512

RESUMO

Aptamers (protein binding oligonucleotides) have potential as a new class of targeted therapeutics. For applications requiring chronic systemic administration, aptamers must achieve high-affinity target binding while simultaneously retaining high in vivo stability, tolerability, and ease of chemical synthesis. To this end, we describe a method for generating aptamers composed entirely of 2'-O-methyl nucleotides (mRmY). We present conditions under which 2'-O-methyl transcripts can be generated directly and use these conditions to select a fully 2'-O-methyl aptamer from a library of 3 x 10(15) unique 2'-O-methyl transcripts. This aptamer, ARC245, is 23 nucleotides in length, binds to vascular endothelial growth factor (VEGF) with a Kd of 2 nM, and inhibits VEGF activity in cellular assays. Notably, ARC245 is so stable that degradation cannot be detected after 96 hr in plasma at 37 degrees C or after autoclaving at 125 degrees C. We believe ARC245 has considerable potential as an antiangiogenesis therapeutic.


Assuntos
Oligonucleotídeos/farmacologia , Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Inibidores da Angiogênese/química , Inibidores da Angiogênese/metabolismo , Inibidores da Angiogênese/farmacologia , Animais , RNA Polimerases Dirigidas por DNA/metabolismo , Endotélio Vascular/efeitos dos fármacos , Biblioteca Gênica , Humanos , Hidrólise , Camundongos , Oligonucleotídeos/química , Oligonucleotídeos/metabolismo , Fatores de Tempo , Fatores de Crescimento do Endotélio Vascular/metabolismo
9.
PLoS One ; 11(10): e0164765, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27764180

RESUMO

Enzyme replacement therapy with intravenous idursulfase (recombinant iduronate-2-sulfatase) is approved for the treatment of Hunter syndrome. Intravenous administration does not, however, treat the neurological manifestations, due to its low central nervous system bioavailability. Using intrathecal-lumbar administration, iduronate-2-sulfatase is delivered directly to the central nervous system. This study investigates the central nervous system biodistribution of intrathecal-lumbar administered iduronate-2-sulfatase in cynomolgus monkeys. Twelve monkeys were administered iduronate-2-sulfatase in one 30 mg intrathecal-lumbar injection. Brain, spinal cord, liver, and kidneys were collected for iduronate-2-sulfatase concentration (measured by an enzyme linked immunosorbent assay) and enzyme activity measurement (via a method utilizing 4-methylumbelliferyl-α-iduronate-2-sulfate) at 1, 2, 5, 12, 24, and 48 hours following administration. The tissue enzyme linked immunosorbent assay confirmed iduronate-2-sulfatase uptake to the brain, spinal cord, kidneys, and liver in a time-dependent manner. In spinal cord and brain, iduronate-2-sulfatase appeared as early as 1 hour following administration, and peak concentrations were observed at ~2 and ~5 hours. Iduronate-2-sulfatase appeared in liver and kidneys 1 hour post intrathecal-lumbar dose with peak concentrations between 5 and 24 hours. Liver iduronate-2-sulfatase concentration was approximately 10-fold higher than kidney. The iduronate-2-sulfatase localization and enzyme activity in the central nervous system, following intrathecal administration, demonstrates that intrathecal-lumbar treatment with iduronate-2-sulfatase may be considered for further investigation as a treatment for Hunter syndrome patients with neurocognitive impairment.


Assuntos
Terapia de Reposição de Enzimas , Iduronato Sulfatase/administração & dosagem , Mucopolissacaridose II/tratamento farmacológico , Animais , Encéfalo/enzimologia , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Iduronato Sulfatase/farmacocinética , Injeções Espinhais , Rim/enzimologia , Fígado/enzimologia , Macaca fascicularis , Masculino , Medula Espinal/enzimologia , Fatores de Tempo , Distribuição Tecidual
10.
Bioanalysis ; 8(4): 285-95, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26847798

RESUMO

AIMS: Heparan sulfate (HS) accumulates in the central nervous system in mucopolysaccharidosis III type A (MPS IIIA). A validated LC-MS/MS assay was developed to measure HS in human cerebrospinal fluid (CSF). METHODS & RESULTS: HS was extracted and digested and the resultant disaccharides were derivatized with a novel label, 4-butylaniline, enabling isoform separation and isotope-tagged analog introduction as an internal standard for LC-MS/MS. The assay has a LLOQ for disaccharides of 0.1 µM, ±20% accuracy and ≤20% precision. CSF samples from patients with MPS IIIA showed elevated HS levels (mean 4.9 µM) compared with negative controls (0.37 µM). CONCLUSION: This assay detected elevated HS levels in the CSF of patients with MPS IIIA and provides a method to assess experimental therapies.


Assuntos
Cromatografia Líquida/métodos , Heparitina Sulfato/líquido cefalorraquidiano , Mucopolissacaridose III/líquido cefalorraquidiano , Espectrometria de Massas em Tandem/métodos , Adolescente , Criança , Pré-Escolar , Cromatografia Líquida/normas , Heparitina Sulfato/isolamento & purificação , Humanos , Lactente , Limite de Detecção , Valores de Referência
11.
Oligonucleotides ; 15(3): 183-95, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16201906

RESUMO

Here, we examine biodistribution of radiolabeled aptamers and assess the relative ability of different stabilized aptamer compositions (mixed 2'-F/2'-O-Me; fully 2'-O-Me modified) to access inflamed tissues in a murine inflammation model. Biodistribution of 3H-labeled aptamers, including pegylated and unpegylated compositions, was assessed 3 hours postadministration using quantitative whole body autoradiography (QWBA). Aptamer penetration of cells in kidney and liver was also examined at a qualitative level by microautoradiography. To evaluate aptamer distribution to diseased tissues, inflammation was induced locally in animal hind limbs by treatment with carrageenan just prior to aptamer dosing. Aptamer compositions examined exhibited significant variation in distribution levels among organs and tissues. Highest concentrations of radioactivity in whole body tissues for all animals were observed in the kidney and urinary bladder contents. Relatively little radioactivity was associated with brain, spinal cord, and adipose tissue. Overall, the total level of radioactivity in whole body tissues was significantly higher for a 20-kDa PEG conjugate than for other aptamers. Comparatively high levels of the 20-kDa conjugate were seen in well-perfused organs and tissues, including liver, lungs, spleen, bone marrow, and myocardium. A fully 2'-O-Me composition aptamer had the lowest level of radioactivity in whole body tissues but distributed to higher concentrations in the gastrointestinal tract contents relative to other aptamers. Interestingly, the 20-kDa PEG-conjugated aptamer showed significantly higher levels of distribution to inflamed paw tissues than did either unconjugated or fully 2'-O-Me-modified aptamers.


Assuntos
Polietilenoglicóis/farmacocinética , Animais , Autorradiografia , Sequência de Bases , Disponibilidade Biológica , Carragenina , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Extremidades , Trato Gastrointestinal/metabolismo , Inflamação/induzido quimicamente , Extremidade Inferior , Masculino , Camundongos , Camundongos Endogâmicos , Dados de Sequência Molecular , Peso Molecular , Polietilenoglicóis/química , Polietilenoglicóis/metabolismo , Polímeros/química , Distribuição Tecidual/efeitos dos fármacos , Distribuição Tecidual/fisiologia , Trítio/metabolismo
12.
Clin Pharmacol Drug Dev ; 4(2): 105-11, 2015 03.
Artigo em Inglês | MEDLINE | ID: mdl-27128215

RESUMO

PURPOSE: Icatibant is a bradykinin-2 receptor antagonist approved to treat acute hereditary angioedema attacks in adults. To-date, no thorough investigation of the clinical pharmacokinetic (PK) parameters of icatibant and its primary metabolites has been reported. Here we present the PK results of two phase I clinical studies of icatibant in healthy human volunteers. METHODS: Single- and multiple-dose plasma pharmacokinetics of icatibant were characterized in healthy volunteers. Icatibant concentration-time profiles and PK parameters were derived after a single 30- or 90-mg dose or three 30-mg doses given at 6-hour intervals. RESULTS: Maximal plasma concentrations for the 30-mg (979 ± 262 ng/mL) and 90-mg doses (2,719 ± 666 ng/mL) were achieved at <1 hour postdose. The total plasma icatibant exposure for the 30- and 90-mg doses was 2,191 ± 565 and 6,736 ± 1,230 h · ng/mL, respectively, with elimination half-life values of 1.48 ± 0.35 and 2.00 ± 0.57 hours, respectively. CONCLUSIONS: Single 30- and 90-mg subcutaneous administration of icatibant exhibited dose-proportional PK with no appreciable accumulation upon repeated 30-mg doses administered at 6-hour intervals.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/farmacocinética , Antagonistas de Receptor B2 da Bradicinina/administração & dosagem , Antagonistas de Receptor B2 da Bradicinina/farmacocinética , Bradicinina/análogos & derivados , Adolescente , Adulto , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/sangue , Área Sob a Curva , Bradicinina/administração & dosagem , Bradicinina/efeitos adversos , Bradicinina/sangue , Bradicinina/farmacocinética , Antagonistas de Receptor B2 da Bradicinina/efeitos adversos , Antagonistas de Receptor B2 da Bradicinina/sangue , Esquema de Medicação , Feminino , Meia-Vida , Voluntários Saudáveis , Humanos , Injeções Subcutâneas , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Modelos Biológicos , Adulto Jovem
13.
PLoS One ; 10(4): e0122453, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25836678

RESUMO

Intravenous enzyme replacement therapy with iduronate-2-sulfatase is an approved treatment for Hunter syndrome, however, conventional intravenous delivery cannot treat the neurologic manifestations of the disease due to its limited central nervous system penetration. Intrathecal administration of iduronate-2-sulfatase for delivery to the central nervous system is currently under investigation. The objective of this study was to evaluate the pharmacokinetics of idursulfase in the central nervous system of cynomolgus monkeys (Macaca fasicularis) after intravenous and intrathecal administration. Twenty-seven monkeys, treatment-naïve to enzyme replacement therapy, were placed into 4 groups according to body weight: Group 1 was administered 0.5 mg/kg idursulfase intravenously, Groups 2-4 were administered an intrathecal formulation (1-, 10-, and 30-mg doses). Blood samples and cerebrospinal fluid (sampled at the cisterna magna or lumbar level) were collected at the same time points for 72 hours post dosing. Following intravenous administration, a high maximum serum concentration and rapid distribution of iduronate-2-sulfatase out of the central compartment were observed (elimination half-life: 4.3 hours). Iduronate-2-sulfatase exposure in the cerebrospinal fluid was limited, suggesting intravenous administration provided minimal penetration of the blood-brain barrier. Following intrathecal administration, a high maximum observed concentration was immediately noted and elimination half-life ranged between 7.8-10 hours and 5.9-6.7 hours (cisterna magna and lumbar sampling, respectively). Cerebrospinal fluid pharmacokinetic profiles at different doses of iduronate-2-sulfatase were similar and the dose/exposure relationship was proportional. After intrathecal administration, movement of iduronate-2-sulfatase from cerebrospinal fluid to serum was observed (systemic bioavailability was 40-83%). The clear penetration of iduronate-2-sulfatase into the cerebrospinal fluid and the dose response suggest that intrathecal delivery of iduronate-2-sulfatase may be suitable for treating the central nervous system manifestations associated with Hunter syndrome.


Assuntos
Iduronato Sulfatase/administração & dosagem , Iduronato Sulfatase/farmacocinética , Administração Intravenosa , Animais , Disponibilidade Biológica , Terapia de Reposição de Enzimas , Feminino , Humanos , Iduronato Sulfatase/líquido cefalorraquidiano , Injeções Espinhais , Macaca fascicularis , Masculino , Mucopolissacaridose II/tratamento farmacológico , Mucopolissacaridose II/enzimologia , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/líquido cefalorraquidiano , Proteínas Recombinantes/farmacocinética
14.
Pharm Res ; 23(2): 303-11, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16411148

RESUMO

PURPOSE: The aim of the study is to determine the bioactivity and effects of PEGylation on the pharmacokinetics in rabbit aqueous humor and plasma of an aptamer directed against TGFbeta2. METHODS: Pharmacological activity of anti-TGFbeta2 aptamer in rabbit ocular fluid was demonstrated using a mink lung epithelial cell proliferation assay. For pharmacokinetic analyses, concentrations of aptamers in plasma and aqueous humor were determined over time following bilateral subconjunctival administration to Dutch-belted rabbits using a hybridization-based pseudo-enzyme-linked immunosorbent assay (ELISA) assay. RESULTS: Anti-TGFbeta2 aptamer (ARC81) binds to human TGFbeta2 with a K(D) of approximately 5 nM and inhibits the activity of human TGFbeta2 in vitro in a cell-based assay with an IC(50) of approximately 100 nM. ARC81 blocks endogenously derived TGFbeta2 in rabbit aqueous humor in vitro with an IC(50) of approximately 200 nM and an IC(90) of approximately 1 microM. In vivo in rabbit, ARC81 [no polyethylene glycol (PEG)] entered systemic circulation rapidly (t(max) = 1 h in plasma) relative to aptamer conjugates ARC117 (20 kDa PEG) and ARC119 (40 kDa PEG), which showed prolonged residence in the subconjunctival space and aqueous compartment (t(max) = 6 and 12 h, respectively, in plasma). Both 20- and 40-kDa aptamer conjugates reached maximal concentrations (C(max)) in aqueous humor of 23-30 nM and remained at or above 1 nM for as long as 12 h. CONCLUSIONS: Pharmacologically active levels of anti-TGFbeta2 aptamers can be sustained in the ocular fluid and local tissue environment over a 12-h period after single administration. Daily subconjunctival administration of PEGylated anti-TGFbeta2 aptamers should allow further pharmacological evaluation of these agents in a rabbit conjunctival scarring model. Perioperative administration, via subconjunctival injection, may prove to be an effective means to deliver therapeutic quantities of TGFbeta2 aptamer conjugates in trabeculectomy procedures.


Assuntos
Humor Aquoso/metabolismo , Fator de Crescimento Transformador beta/antagonistas & inibidores , Animais , Área Sob a Curva , Bioensaio , Proliferação de Células/efeitos dos fármacos , Química Farmacêutica , Ensaio de Imunoadsorção Enzimática , Células Epiteliais/metabolismo , Humanos , Pulmão/citologia , Pulmão/metabolismo , Vison , Oligonucleotídeos/síntese química , Oligonucleotídeos/farmacologia , Polietilenoglicóis , Coelhos , Fator de Crescimento Transformador beta2
15.
Anal Biochem ; 319(2): 244-50, 2003 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-12871718

RESUMO

We have developed a chip-based biosensor for multiplex analysis of protein analytes. The biosensor utilizes immobilized DNA and RNA aptamers, selected against several different protein targets, to simultaneously detect and quantify levels of individual proteins in complex biological mixtures. Aptamers were each fluorescently labeled and immobilized on a glass substrate. Fluorescence polarization anisotropy was used for solid- and solution-phase measurements of target protein binding. We show that solid-phase aptamer-protein interactions recapitulate binding interactions seen in solution. Furthermore, we demonstrate specific detection and quantitation of cancer-associated proteins (inosine monophosphate dehydrogenase II, vascular endothelial factor, basic fibroblast growth factor) in the context of human serum and in cellular extracts. It is expected that this technology could speed diagnosis of cancer by enabling direct detection of the expression and modification of proteins closely correlated with disease.


Assuntos
Técnicas Biossensoriais , DNA/química , Fator 2 de Crescimento de Fibroblastos/análise , IMP Desidrogenase/análise , RNA/química , Fatores de Crescimento do Endotélio Vascular/análise , Anisotropia , Fator 2 de Crescimento de Fibroblastos/metabolismo , Polarização de Fluorescência/instrumentação , Polarização de Fluorescência/métodos , Humanos , IMP Desidrogenase/metabolismo , Isoenzimas , Ligação Proteica , Trombina/química , Fatores de Crescimento do Endotélio Vascular/metabolismo
16.
Pharm Res ; 21(12): 2234-46, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15648255

RESUMO

PURPOSE: Aptamers are highly selective nucleic acid-based drugs that are currently being developed for numerous therapeutic indications. Here, we determine plasma pharmacokinetics and tissue distribution in rat of several novel aptamer compositions, including fully 2'-O-methylated oligonucleotides and conjugates bearing high-molecular weight polyethylene glycol (PEG) polymers, cell-permeating peptides, and cholesterol. METHODS: Levels of aptamer conjugates in biological samples were quantified radiometrically and by a hybridization-based dual probe capture assay with enzyme-linked fluorescent readout. Intact aptamer in urine was detected by capillary gel electrophoresis and matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF). RESULTS: Aptamer compositions examined exhibited a wide range of mean residence times in circulation (0.6-16 h) and significant variation in distribution levels among organs and tissues. Among the conjugates tested, in vivo properties of aptamers were altered most profoundly by conjugation with PEG groups. Complexation with a 20 kDa PEG polymer proved nearly as effective as a 40 kDa PEG polymer in preventing renal clearance of aptamers. Conjugation with 20 kDa PEG prolonged aptamer circulatory half-life, while reducing both the extent of aptamer distribution to the kidneys and the rate of urinary elimination. In contrast, the fully 2'-O-Me aptamer composition showed rapid clearance from circulation, and elimination with intact aptamer detectable in urine at 48 h post-administration. CONCLUSIONS: We find that conjugation and chemical composition can alter fundamental aspects of aptamer residence in circulation and distribution to tissues. Though the primary effect of PEGylation was on aptamer clearance, the prolonged systemic exposure afforded by presence of the 20 kDa moiety appeared to facilitate distribution of aptamer to tissues, particularly those of highly perfused organs.


Assuntos
Oligonucleotídeos/química , Oligonucleotídeos/farmacocinética , Animais , Disponibilidade Biológica , Química Farmacêutica , Relação Dose-Resposta a Droga , Masculino , Oligonucleotídeos/metabolismo , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual/efeitos dos fármacos , Distribuição Tecidual/fisiologia
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