Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 82
Filtrar
1.
Cereb Cortex ; 34(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38602735

RESUMO

Developmental changes that occur before birth are thought to be associated with the development of autism spectrum disorders. Identifying anatomical predictors of early brain development may contribute to our understanding of the neurobiology of autism spectrum disorders and allow for earlier and more effective identification and treatment of autism spectrum disorders. In this study, we used retrospective clinical brain magnetic resonance imaging data from fetuses who were diagnosed with autism spectrum disorders later in life (prospective autism spectrum disorders) in order to identify the earliest magnetic resonance imaging-based regional volumetric biomarkers. Our results showed that magnetic resonance imaging-based autism spectrum disorder biomarkers can be found as early as in the fetal period and suggested that the increased volume of the insular cortex may be the most promising magnetic resonance imaging-based fetal biomarker for the future emergence of autism spectrum disorders, along with some additional, potentially useful changes in regional volumes and hemispheric asymmetries.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Humanos , Transtorno Autístico/diagnóstico por imagem , Transtorno do Espectro Autista/diagnóstico por imagem , Estudos Prospectivos , Estudos Retrospectivos , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Biomarcadores
2.
J Pept Sci ; 30(7): e3592, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38447547

RESUMO

The CRISPR-Cas9 system has revolutionized the field of genetic engineering, but targeted cellular delivery remains a central problem. The delivery of the preformed ribonuclease-protein (RNP) complex has the advantages of fewer side effects and avoidance of potential permanent effects. We reasoned that an internalizing IgG antibody as a targeting device could address the delivery of Cas9-RNP. We opted for protein trans-splicing mediated by a split intein to facilitate posttranslational conjugation of the two large protein entities. We recently described the cysteine-less CL split intein that efficiently performs under oxidizing conditions and does not interfere with disulfide bonds or thiol bioconjugation chemistries. Using the CL split intein, we report for the first time the ligation of monoclonal IgG antibody precursors, expressed in mammalian cells, and a Cas9 precursor, obtained from bacterial expression. A purified IgG-Cas9 conjugate was loaded with sgRNA to form the active RNP complex and introduced a double-strand break in its target DNA in vitro. Furthermore, a synthetic peptide variant of the short N-terminal split intein precursor proved useful for chemical modification of Cas9. The split intein ligation procedure reported here for IgG-Cas9 provides the first step towards a novel CRISPR-Cas9 targeting approach involving the preformed RNP complex.


Assuntos
Sistemas CRISPR-Cas , Imunoglobulina G , Inteínas , Imunoglobulina G/química , Imunoglobulina G/genética , Humanos , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/metabolismo , Proteína 9 Associada à CRISPR/química
3.
Am J Med Genet C Semin Med Genet ; 193(4): e32069, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37870763

RESUMO

Individuals with Down syndrome (DS) or Autism Spectrum Disorder (ASD), and especially those with both DS and co-occurring ASD (DS + ASD) commonly display behavioral and psychiatric symptoms that can impact quality of life and places increased burden on caregivers. While the mainstay of treatment in DS and ASD is focused on educational and behavioral therapies, pharmacological treatments can be used to reduce symptom burden. There is a paucity of evidence and limited clinical trials in DS and DS + ASD. Some scientific evidence is available, primarily in open label studies and case series that can guide treatment choices. Additionally, clinical decisions are often extrapolated from evidence and experience from those with ASD, or intellectual disability in those without DS. This article reviews current research in pharmacological treatment in DS, ASD, and DS + ASD, reviews co-occurring neurodevelopmental and mental health diagnoses in individuals with DS + ASD across the lifespan, and describes practical approaches to psychopharmacological management.


Assuntos
Transtorno do Espectro Autista , Síndrome de Down , Deficiência Intelectual , Humanos , Transtorno do Espectro Autista/tratamento farmacológico , Transtorno do Espectro Autista/diagnóstico , Síndrome de Down/complicações , Síndrome de Down/tratamento farmacológico , Síndrome de Down/diagnóstico , Qualidade de Vida
4.
Am J Med Genet C Semin Med Genet ; 193(4): e32072, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37873945

RESUMO

Individuals with Down syndrome (DS) experience a range of medical and neurodevelopmental conditions, necessitating systematic study of their occurrence and impact on neurodevelopmental outcomes. We describe the prevalence and relationships of medical, neurodevelopmental (ND), and mental health (MH) conditions in children with DS. We created a prospective clinical database of individuals with DS, integrated into the workflow of a specialty Down Syndrome Program at a specialty pediatric referral hospital. Conditions were collected through caregiver- and clinician report at clinical visits (N = 599). We calculated frequencies of medical, ND, and MH conditions and then assessed the relationship between medical, ND, and MH conditions using frequencies and comparative statistics. The most frequent co-occurring conditions were vision (72.5%), ear/hearing (71.0%), gastrointestinal (61.3%), respiratory (45.6%), and feeding (33.6%) problems, with variation in frequency by age. ND and MH conditions were reported in one quarter, most commonly autism spectrum disorder and attention-deficit/hyperactivity disorder. Those with ND and MH conditions had greater frequency of medical conditions, with highest rates of vision, ear/hearing, and gastrointestinal issues, and CHD. Systematically collected clinical data in a large cohort of children with DS reveals high prevalence of several co-occurring medical, ND, and MH conditions. Clinical care requires an understanding of the complex relationship between medical conditions and neurodevelopment.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Espectro Autista , Síndrome de Down , Transtornos do Neurodesenvolvimento , Criança , Humanos , Síndrome de Down/complicações , Síndrome de Down/epidemiologia , Transtorno do Espectro Autista/epidemiologia , Estudos Prospectivos
5.
Am J Med Genet A ; 191(3): 813-822, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36538912

RESUMO

Individuals with Down syndrome (DS) are at increased risk for being overweight/obese, but the associated cardiometabolic risk (CR) is not clear. Cross-sectional anthropometric and clinical laboratory data from a multi-site, international cohort of individuals with DS were analyzed to determine cardiometabolic risk by reporting observed distributions of cardiometabolic biomarkers in overweight/obese individuals with DS throughout the lifespan. Descriptive statistics and regression analyses by age categories determined the distributive percentiles for cardiometabolic biomarkers and tested for adiposity as a predictor of CR. Across seven DS clinics, data were collected on 240 patients between the ages of 3 and 63 years, with one quarter overweight and three quarters obese among children and nearly all adults being obese. In children and adults, most cardiometabolic biomarker profiles showed distributive values within normal ranges. Blood lipids were positively associated with body mass index (BMI) in children (high density lipid-cholesterol, p = 0.01; low density lipid-cholesterol, p = 0.02). Levels of hs-CRP were elevated in both children and adults, with BMI positively associated with hs-CRP in adults with DS (p = 0.04). Liver enzyme values were positively associated with BMI in children and adults. The data suggest that in contrast to the general population, in individuals with Down syndrome, being overweight and obese does not appear to confer a significantly increased risk for cardiometabolic disease by biomarker profile. Individuals with DS who are overweight/obese appear to have unique cardiometabolic profiles unrelated to adiposity, notable for increased hs-CRP and normal HA1c levels.


Assuntos
Doenças Cardiovasculares , Síndrome de Down , Doenças Metabólicas , Humanos , Criança , Adulto , Pré-Escolar , Adolescente , Adulto Jovem , Pessoa de Meia-Idade , Sobrepeso/complicações , Sobrepeso/epidemiologia , Proteína C-Reativa/análise , Síndrome de Down/complicações , Síndrome de Down/epidemiologia , Estudos Transversais , Fatores de Risco , Obesidade/complicações , Índice de Massa Corporal , Biomarcadores , Lipídeos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia
6.
Am J Med Genet A ; 188(10): 3049-3062, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35924793

RESUMO

Research to guide clinicians in the management of the devastating regression which can affect adolescents and young adults with Down syndrome is limited. A multi-site, international, longitudinal cohort of individuals with a clinical diagnosis of Unexplained Regression in Down syndrome (URDS) was collated through seven Down syndrome clinics. Tiered medical evaluation, a 28-item core symptom list, and interim management are described naturalistically. Improvement-defined by the percentage of baseline function on a Parent-reported Functional Score, overall improvement in symptoms on a Clinician-administered Functional Assessment, or report of management type being associated with improvement-was analyzed. Improvement rates using ECT, IVIG, and others were compared. Across seven clinics, 51 patients with URDS had regression at age 17.6 years, on average, and showed an average 14.1 out of 28 symptoms. Longitudinal improvement in function was achieved in many patients and the medical management, types of treatment, and their impact on function are described. Management with intravenous immunoglobulin (IVIG) was significantly associated with higher rate of improvement in symptoms at the next visit (p = 0.001). Our longitudinal data demonstrates that URDS is treatable, with various forms of clinical management and has a variable course. The data suggests that IVIG may be an effective treatment in some individuals. Our description of the management approaches used in this cohort lays the groundwork for future research, such as development of standardized objective outcome measure and creation of a clinical practice guideline for URDS.


Assuntos
Síndrome de Down , Adolescente , Síndrome de Down/complicações , Síndrome de Down/epidemiologia , Síndrome de Down/terapia , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Avaliação de Resultados em Cuidados de Saúde , Resultado do Tratamento , Adulto Jovem
7.
J Intellect Disabil ; : 17446295221133874, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36245216

RESUMO

Down syndrome (DS) is a complex condition associated with multiple medical, developmental, and behavioral concerns. A prospective, longitudinal clinical database was integrated into a specialty Down Syndrome Program, with the goals of better understanding the incidence, course, and impact of co-occurring medical, neurodevelopmental, and mental health conditions in DS. We describe the process of developing the database, including a systematic approach to data collection and database infrastructure, and report on feasibility, challenges, and solutions of initial implementation. Between March 2018 and November 2021, data from 842 patients (ages 4.8 months to 26 years) was collected. Challenges included caregiver form completion as well as time and personnel required for successful implementation. With full integration into clinical visit flow, the database proved to be feasible. The database enables identification of patterns of development and health throughout the lifespan and it facilitates future data sharing and collaborative research to advance care.

8.
Angew Chem Int Ed Engl ; 61(1): e202109769, 2022 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-34725904

RESUMO

Ibrutinib is an inhibitor of Bruton's tyrosine kinase that has been approved for the treatment of patients with chronic lymphocytic leukemia, mantle cell lymphoma and Waldenstrom's macroglobulinemia and is connected with toxicities. To minimize its toxicities, we linked ibrutinib to a cell-targeted, internalizing antibody. To this end, we synthesized a poly-anionic derivate, ibrutinib-Cy3.5, that retains full functionality. This anionic inhibitor is complexed by our anti-CD20-protamine targeting conjugate and free protamine, and thereby spontaneously assembles into an electrostatically stabilized vesicular nanocarrier. The complexation led to an accumulation of the drug driven by the CD20 antigen internalization to the intended cells and an amplification of its pharmacological effectivity. In vivo, we observed a significant enrichment of the drug in xenograft lymphoma tumors in immune-compromised mice and a significantly better response to lower doses compared to the original drug.


Assuntos
Adenina/análogos & derivados , Anticorpos Monoclonais/farmacologia , Antineoplásicos/farmacologia , Carbocianinas/farmacologia , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Piperidinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Adenina/química , Adenina/farmacologia , Animais , Anticorpos Monoclonais/química , Antineoplásicos/química , Carbocianinas/química , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Linfoma Difuso de Grandes Células B/patologia , Camundongos , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Piperidinas/química , Engenharia de Proteínas , Inibidores de Proteínas Quinases/química , Eletricidade Estática
9.
Int J Mol Sci ; 21(23)2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33255664

RESUMO

A microfluidic assay for the detection of promyelocytic leukemia (PML)-retinoic acid receptor α (RARα) fusion protein was developed. This microfluidic-based system can be used for rapid personalized differential diagnosis of acute promyelocyte leukemia (APL) with the aim of early initiation of individualized therapy. The fusion protein PML-RARα occurs in 95% of acute promyelocytic leukemia cases and is considered as diagnostically relevant. The fusion protein is formed as a result of translocation t(15,17) and is detected in the laboratory by fluorescence in situ hybridization (FISH) or reverse transcriptase polymerase chain reaction (RT-PCR). Diagnostic methods require many laboratory steps with specialized staff. The developed microfluidic assay includes a sandwich enzyme-linked immunosorbent assay (ELISA) system for PML-RARα on surface of magnetic microparticles in a microfluidic chip. A rapid detection of PML-RARα in cell lysates is achieved in less than one hour. A biotinylated PML-antibody on the surface of magnetic streptavidin coated microparticles is used as capture antibody. The bound translocation product is detected by a RARα antibody conjugated with horseradish peroxidase and the substrate QuantaRed. The analysis is performed in microfluidic channels which involves automated liquid processing with stringent washing and short incubation times. The results of the developed assay show that cell lysates of PML-RARα-positive cells (NB-4) can be clearly distinguished from PML-RARα-negative cells (HL-60, MV4-11).


Assuntos
Leucemia Promielocítica Aguda/diagnóstico , Proteínas de Fusão Oncogênica/genética , Proteína da Leucemia Promielocítica/genética , Receptor alfa de Ácido Retinoico/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/isolamento & purificação , Células Precursoras de Granulócitos/metabolismo , Células Precursoras de Granulócitos/patologia , Humanos , Hibridização in Situ Fluorescente/métodos , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/patologia , Microfluídica/métodos , Proteínas de Fusão Oncogênica/isolamento & purificação , Medicina de Precisão , Translocação Genética/genética
10.
Epilepsy Behav ; 92: 57-60, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30616066

RESUMO

INTRODUCTION: Infantile spasms (IS) are the most frequent epilepsy syndrome in children with Down syndrome (DS). In DS, cellular (synaptic/dendritic changes) and molecular mechanisms are believed to contribute to epileptogenesis, rather than gross structural anomalies. Neuroimaging is a standard part of the evaluation of newly diagnosed infantile epilepsy including IS and, in this age group, often requires sedation. It is unclear if neuroimaging provides additional clinically useful etiologic information in IS associated with DS. METHODS: We conducted a retrospective chart review and detailed neuroimaging review in 36 patients (24 males) with IS and DS, cared for at Boston Children's Hospital. RESULTS: Incidental imaging abnormalities were common (42%), but potentially relevant etiologic abnormalities were rare (16%). Structural congenital or acquired abnormalities were associated with ongoing antiepileptic drug (AED) use (p = 0.02), as well as refractory epilepsy (p = 0.04). However, neuroimaging did not alter the treatment plan for any of these patients. CONCLUSIONS: Clinicians must carefully weigh the benefits and risks of neuroimaging in infants with DS and IS, as neuroimaging did not lead to any changes in clinical management in our patients but may offer information regarding prognosis.


Assuntos
Encéfalo/diagnóstico por imagem , Síndrome de Down/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Espasmos Infantis/diagnóstico por imagem , Anticonvulsivantes/uso terapêutico , Boston/epidemiologia , Pré-Escolar , Estudos de Coortes , Síndrome de Down/tratamento farmacológico , Síndrome de Down/epidemiologia , Feminino , Seguimentos , Humanos , Lactente , Imageamento por Ressonância Magnética/tendências , Masculino , Estudos Retrospectivos , Espasmos Infantis/tratamento farmacológico , Espasmos Infantis/epidemiologia
11.
Blood ; 127(12): 1575-86, 2016 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-26729896

RESUMO

The de novo DNA methyltransferases Dnmt3a and Dnmt3b are of crucial importance in hematopoietic stem cells. Dnmt3b has recently been shown to play a role in genic methylation. To investigate how Dnmt3b-mediated DNA methylation affects leukemogenesis, we analyzed leukemia development under conditions of high and physiological methylation levels in a tetracycline-inducible knock-in mouse model. High expression of Dnmt3b slowed leukemia development in serial transplantations and impaired leukemia stem cell (LSC) function. Forced Dnmt3b expression induced widespread DNA hypermethylation inMyc-Bcl2-induced leukemias, preferentially at gene bodies.MLL-AF9-induced leukemogenesis showed much less pronounced DNA hypermethylation upon Dnmt3b expression. Nonetheless, leukemogenesis was delayed in both models with a shared core set of DNA hypermethylated regions and suppression of stem cell-related genes. Acute myeloid leukemia patients with high expression of Dnmt3b target genes showed inferior survival. Together, these findings indicate a critical role for Dnmt3b-mediated DNA methylation in leukemia development and maintenance of LSC function.


Assuntos
Carcinogênese/genética , DNA (Citosina-5-)-Metiltransferases/genética , Metilação de DNA , Regulação Leucêmica da Expressão Gênica , Leucemia/genética , Animais , Carcinogênese/patologia , Técnicas de Introdução de Genes , Hematopoese , Humanos , Leucemia/diagnóstico , Leucemia/patologia , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Prognóstico , Regiões Promotoras Genéticas , DNA Metiltransferase 3B
13.
BMC Physiol ; 18(1): 3, 2018 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-29482530

RESUMO

BACKGROUND: Inflammatory stimuli induce the hepatic iron regulatory hormone hepcidin, which contributes to anaemia of inflammation (AI). Hepcidin expression is regulated by the bone morphogenetic protein (BMP) and the interleukin-6 (IL-6) signalling pathways. Prior results indicate that the BMP type I receptor ALK3 is mainly involved in the acute inflammatory hepcidin induction four and 72 h after IL-6 administration. In this study, the role of ALK3 in a chronic model of inflammation was investigated. The intact, heat-killed bacterium Brucella abortus (BA) was used to analyse its effect on the development of inflammation and hypoferremia in mice with hepatocyte-specific Alk3-deficiency (Alk3fl/fl; Alb-Cre) compared to control (Alk3fl/fl) mice. RESULTS: An iron restricted diet prevented development of the iron overload phenotype in mice with hepatocyte-specific Alk3 deficiency. Regular diet leads to iron overload and increased haemoglobin levels in these mice, which protects from the development of AI per se. Fourteen days after BA injection Alk3fl/fl; Alb-Cre mice presented milder anaemia (Hb 16.7 g/dl to 11.6 g/dl) compared to Alk3fl/fl control mice (Hb 14.9 g/dl to 8.6 g/dl). BA injection led to an intact inflammatory response in all groups of mice. In Alk3fl/fl; Alb-Cre mice, SMAD1/5/8 phosphorylation was reduced after BA as well as after infection with Staphylococcus aureus. The reduction of the SMAD1/5/8 signalling pathway due to hepatocyte-specific Alk3 deficiency partly suppressed the induction of STAT3 signalling. CONCLUSION: The results reveal in vivo, that 1) hepatocyte-specific Alk3 deficiency partly protects from AI, 2) the development of hypoferremia is partly dependent on ALK3, and 3) the ALK3/BMP/hepcidin axis may serve as a possible therapeutic target to attenuate AI.


Assuntos
Anemia/metabolismo , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/deficiência , Inflamação/metabolismo , Anemia/complicações , Animais , Brucella abortus , Brucelose/complicações , Eritropoese , Feminino , Hepatócitos/metabolismo , Inflamação/etiologia , Mediadores da Inflamação/metabolismo , Camundongos Endogâmicos C57BL , Fosforilação , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Proteína Smad1/metabolismo , Proteína Smad5/metabolismo , Proteína Smad8/metabolismo
15.
Am J Med Genet A ; 173(11): 3029-3041, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28884975

RESUMO

Although an increasing number of clinical trials have been developed for cognition in Down syndrome, there has been limited success to date in identifying effective interventions. This review describes the progression from pre-clinical studies with mouse models to human clinical trials research using pharmacological interventions to improve cognition and adaptive functioning in Down syndrome. We also provide considerations for investigators when conducting human clinical trials and describe strategies for the pharmaceutical industry to advance the field in drug discovery for Down syndrome. Future research focusing on earlier pharmaceutical interventions, development of appropriate outcome measures, and greater collaboration between industry, academia, advocacy, and regulatory groups will be important for addressing limitations from prior studies and developing potential effective interventions for cognition in Down syndrome.


Assuntos
Cognição/efeitos dos fármacos , Disfunção Cognitiva/tratamento farmacológico , Síndrome de Down/tratamento farmacológico , Animais , Disfunção Cognitiva/genética , Disfunção Cognitiva/fisiopatologia , Síndrome de Down/genética , Síndrome de Down/fisiopatologia , Humanos , Camundongos
16.
Am J Med Genet A ; 173(6): 1539-1545, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28332275

RESUMO

The goals of this undertaking were to assess the outcomes of thyroid screening tests and adherence to thyroid screening guidelines across five Down syndrome (DS) specialty clinics in various states. Data related to thyroid screening were collected for 663 individuals across five clinics specializing in the comprehensive care of individuals with DS for a period of 1 year. Of the 663 participants, 47.7% of participants had a TSH and free T4 ordered at their DS specialty clinic visit. Approximately 19.0% (60/316) had a new thyroid disorder diagnosis made. We conclude that a sizable proportion of the patients with DS are not up-to-date on current guidelines when they present to a DS specialty clinic, while adherence to thyroid screening guidelines helps facilitate early diagnoses. Hypothyroidism is prevalent in the population, consistent with reported literature. DS specialty clinics can help patients stay current on screening guidelines.


Assuntos
Síndrome de Down/fisiopatologia , Hipotireoidismo/fisiopatologia , Doenças da Glândula Tireoide/fisiopatologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Síndrome de Down/sangue , Síndrome de Down/complicações , Feminino , Humanos , Hipotireoidismo/sangue , Hipotireoidismo/complicações , Lactente , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Doenças da Glândula Tireoide/sangue , Doenças da Glândula Tireoide/complicações , Testes de Função Tireóidea , Glândula Tireoide/fisiopatologia , Tireotropina/sangue , Tiroxina/sangue
17.
Mol Pharm ; 14(5): 1339-1351, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28170265

RESUMO

RNA interference strategies offer an alternative to small molecular drug targeting. Small interfering RNA (siRNA) constitutes a class of molecules that allows the effective and specific inhibition of the biosynthesis of any protein. Indeed, siRNA have emerged as a major tool in molecular biology techniques and an important approach to identify suitable therapy targets in cancer. However, siRNA therapy approaches in vivo are scarce. Two major problems hinder siRNA as a therapeutic tool: (1) delivery through the bloodstream leads to degradation or rapid renal clearance (stabilization) and (2) specific uptake by the desired cell type (specificity). This review summarizes the ongoing attempts to use RNAi against disease-causing factors. We compare methods to stabilize siRNA in different conjugates and that decorate these complexes with targeting molecules such as antibodies, single-chain Fv or Fab fragments, to enable specific uptake of the carriers by the respective cells. We propose the development of antibody-coupled siRNA complexes, which have shown to allow stabilization as well as targeted uptake of siRNA to cancer cells.


Assuntos
Anticorpos/química , RNA Interferente Pequeno/administração & dosagem , Fragmentos Fab das Imunoglobulinas/química , Interferência de RNA , RNA Interferente Pequeno/química
18.
Am J Med Genet A ; 170(12): 3098-3105, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27605215

RESUMO

The main purposes of this undertaking were to determine how often patients with Down syndrome (DS) are screened for celiac disease (CD) across five DS specialty clinics, which symptoms of CD are most often reported to DS specialty providers at these clinics, and, how many individuals were diagnosed with CD by these clinics. This was accomplished by following 663 individuals with DS for 1 year, across five clinics in different states specializing in the comprehensive care of people with DS. Of the 663 participants, 114 individuals were screened for CD at their visit to a DS specialty clinic. Protracted constipation (43.2%) and refractory behavioral problems (23.7%) were symptoms most often reported to DS specialty providers. During the 1 year study period, 13 patients screened positive for CD by serology. Of those, eight underwent duodenal biopsy, and three were diagnosed with CD. We conclude that CD is an important consideration in the comprehensive care of individuals with DS. However, while symptoms are common, diagnoses are infrequent in DS specialty clinics. © 2016 Wiley Periodicals, Inc.


Assuntos
Doença Celíaca/diagnóstico , Síndrome de Down/diagnóstico , Aconselhamento Genético , Adolescente , Adulto , Biópsia , Doença Celíaca/complicações , Doença Celíaca/fisiopatologia , Criança , Pré-Escolar , Síndrome de Down/complicações , Síndrome de Down/fisiopatologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Adulto Jovem
19.
Am J Med Genet A ; 167A(11): 2520-6, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26249752

RESUMO

The Down Syndrome Study Group (DSSG) was founded in 2012 as a voluntary, collaborative effort with the goal of supporting evidenced-based health care guidelines for individuals with Down syndrome (DS). Since then, 5 DS specialty clinics have collected prospective, longitudinal data on medical conditions that co-occur with DS. Data were entered by clinical staff or trained designees into the National Down Syndrome Patient Database, which we created using REDCap software. In our pilot year, we enrolled 663 participants across the U.S., ages 36 days to 70 years, from multiple racial and ethnic backgrounds. Here we report: (i) the demographic distribution of participants enrolled, (ii) a detailed account of our database infrastructure, and (iii) lessons learned during our pilot year to assist future researchers with similar goals for other patient populations.


Assuntos
Bases de Dados Factuais , Síndrome de Down/epidemiologia , Estudos Multicêntricos como Assunto , Sistema de Registros , Adolescente , Adulto , Criança , Pré-Escolar , Comportamento Cooperativo , Demografia , Feminino , Humanos , Lactente , Recém-Nascido , Estudos Interdisciplinares , Masculino , Estados Unidos/epidemiologia , Adulto Jovem
20.
Blood ; 119(10): 2346-57, 2012 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-22207736

RESUMO

With the use of ChIP on microarray assays in primary leukemia samples, we report that acute myeloid leukemia (AML) blasts exhibit significant alterations in histone H3 acetylation (H3Ac) levels at > 1000 genomic loci compared with CD34(+) progenitor cells. Importantly, core promoter regions tended to have lower H3Ac levels in AML compared with progenitor cells, which suggested that a large number of genes are epigenetically silenced in AML. Intriguingly, we identified peroxiredoxin 2 (PRDX2) as a novel potential tumor suppressor gene in AML. H3Ac was decreased at the PRDX2 gene promoter in AML, which correlated with low mRNA and protein expression. We also observed DNA hypermethylation at the PRDX2 promoter in AML. Low protein expression of the antioxidant PRDX2 gene was clinically associated with poor prognosis in patients with AML. Functionally, PRDX2 acted as inhibitor of myeloid cell growth by reducing levels of reactive oxygen species (ROS) generated in response to cytokines. Forced PRDX2 expression inhibited c-Myc-induced leukemogenesis in vivo on BM transplantation in mice. Taken together, epigenome-wide analyses of H3Ac in AML led to the identification of PRDX2 as an epigenetically silenced growth suppressor, suggesting a possible role of ROS in the malignant phenotype in AML.


Assuntos
Metilação de DNA , Histonas/metabolismo , Peroxirredoxinas/genética , Proteínas Supressoras de Tumor/genética , Acetilação , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Proliferação de Células , Células Cultivadas , Epigênese Genética , Feminino , Perfilação da Expressão Gênica/métodos , Estudo de Associação Genômica Ampla , Células HL-60 , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Peroxirredoxinas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Células U937 , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa