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1.
J Perinatol ; 41(8): 2072-2087, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33758387

RESUMO

OBJECTIVE: This study evaluates the 24-month follow-up for the NICHD Neonatal Research Network (NRN) Inositol for Retinopathy Trial. STUDY DESIGN: Bayley Scales of Infants Development-III and a standardized neurosensory examination were performed in infants enrolled in the main trial. Moderate/severe NDI was defined as BSID-III Cognitive or Motor composite score <85, moderate or severe cerebral palsy, blindness, or hearing loss that prevents communication despite amplification were assessed. RESULTS: Primary outcome was determined for 605/638 (95%). The mean gestational age was 25.8 ± 1.3 weeks and mean birthweight was 805 ± 192 g. Treatment group did not affect the risk for the composite outcome of death or survival with moderate/severe NDI (60% vs 56%, p = 0.40). CONCLUSIONS: Treatment group did not affect the risk of death or survival with moderate/severe NDI. Despite early termination, this study represents the largest RCT of extremely preterm infants treated with myo-inositol with neurodevelopmental outcome data.


Assuntos
Paralisia Cerebral , Lactente Extremamente Prematuro , Desenvolvimento Infantil , Idade Gestacional , Humanos , Recém-Nascido , Inositol/uso terapêutico
2.
JAMA ; 320(16): 1649-1658, 2018 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-30357297

RESUMO

Importance: Previous studies of myo-inositol in preterm infants with respiratory distress found reduced severity of retinopathy of prematurity (ROP) and less frequent ROP, death, and intraventricular hemorrhage. However, no large trials have tested its efficacy or safety. Objective: To test the adverse events and efficacy of myo-inositol to reduce type 1 ROP among infants younger than 28 weeks' gestational age. Design, Setting, and Participants: Randomized clinical trial included 638 infants younger than 28 weeks' gestational age enrolled from 18 neonatal intensive care centers throughout the United States from April 17, 2014, to September 4, 2015; final date of follow-up was February 12, 2016. The planned enrollment of 1760 participants would permit detection of an absolute reduction in death or type 1 ROP of 7% with 90% power. The trial was terminated early due to a statistically significantly higher mortality rate in the myo-inositol group. Interventions: A 40-mg/kg dose of myo-inositol was given every 12 hours (initially intravenously, then enterally when feeding; n = 317) or placebo (n = 321) for up to 10 weeks. Main Outcomes and Measures: Type 1 ROP or death before determination of ROP outcome was designated as unfavorable. The designated favorable outcome was survival without type 1 ROP. Results: Among 638 infants (mean, 26 weeks' gestational age; 50% male), 632 (99%) received the trial drug or placebo and 589 (92%) had a study outcome. Death or type 1 ROP occurred more often in the myo-inositol group vs the placebo group (29% vs 21%, respectively; adjusted risk difference, 7% [95% CI, 0%-13%]; adjusted relative risk, 1.41 [95% CI, 1.08-1.83], P = .01). All-cause death before 55 weeks' postmenstrual age occurred in 18% of the myo-inositol group and in 11% of the placebo group (adjusted risk difference, 6% [95% CI, 0%-11%]; adjusted relative risk, 1.66 [95% CI, 1.14-2.43], P = .007). The most common serious adverse events up to 7 days of receiving the ending dose were necrotizing enterocolitis (6% for myo-inositol vs 4% for placebo), poor perfusion or hypotension (7% vs 4%, respectively), intraventricular hemorrhage (10% vs 9%), systemic infection (16% vs 11%), and respiratory distress (15% vs 13%). Conclusions and Relevance: Among premature infants younger than 28 weeks' gestational age, treatment with myo-inositol for up to 10 weeks did not reduce the risk of type 1 ROP or death vs placebo. These findings do not support the use of myo-inositol among premature infants; however, the early termination of the trial limits definitive conclusions.


Assuntos
Lactente Extremamente Prematuro , Doenças do Recém-Nascido/mortalidade , Inositol/uso terapêutico , Retinopatia da Prematuridade/prevenção & controle , Hemorragia Cerebral Intraventricular/prevenção & controle , Método Duplo-Cego , Feminino , Seguimentos , Idade Gestacional , Humanos , Recém-Nascido , Inositol/efeitos adversos , Terapia Intensiva Neonatal , Masculino , Retinopatia da Prematuridade/mortalidade , Falha de Tratamento
3.
Nat Commun ; 7: 10846, 2016 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-27029405

RESUMO

A hallmark of inflammatory diseases is the excessive recruitment and influx of monocytes to sites of tissue damage and their ensuing differentiation into macrophages. Numerous stimuli are known to induce transcriptional changes associated with macrophage phenotype, but posttranscriptional control of human macrophage differentiation is less well understood. Here we show that expression levels of the RNA-binding protein Quaking (QKI) are low in monocytes and early human atherosclerotic lesions, but are abundant in macrophages of advanced plaques. Depletion of QKI protein impairs monocyte adhesion, migration, differentiation into macrophages and foam cell formation in vitro and in vivo. RNA-seq and microarray analysis of human monocyte and macrophage transcriptomes, including those of a unique QKI haploinsufficient patient, reveal striking changes in QKI-dependent messenger RNA levels and splicing of RNA transcripts. The biological importance of these transcripts and requirement for QKI during differentiation illustrates a central role for QKI in posttranscriptionally guiding macrophage identity and function.


Assuntos
Macrófagos/fisiologia , Monócitos/fisiologia , Splicing de RNA , Proteínas de Ligação a RNA/fisiologia , Animais , Aterosclerose/metabolismo , Aterosclerose/patologia , Diferenciação Celular , Células Espumosas/citologia , Células Espumosas/metabolismo , Regulação da Expressão Gênica , Humanos , Macrófagos/citologia , Macrófagos/metabolismo , Camundongos , Modelos Biológicos , Modelos Genéticos , Monócitos/citologia , Monócitos/metabolismo , RNA Mensageiro/metabolismo , RNA Mensageiro/fisiologia , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
4.
J Virol ; 89(4): 2415-24, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25505075

RESUMO

UNLABELLED: Members of the APOBEC3 family of cytidine deaminases vary in their proportions of a virion-incorporated enzyme that is localized to mature retrovirus cores. We reported previously that APOBEC3F (A3F) was highly localized into mature human immunodeficiency virus type 1 (HIV-1) cores and identified that L306 in the C-terminal cytidine deaminase (CD) domain contributed to its core localization (C. Song, L. Sutton, M. Johnson, R. D'Aquila, J. Donahue, J Biol Chem 287:16965-16974, 2012, http://dx.doi.org/10.1074/jbc.M111.310839). We have now determined an additional genetic determinant(s) for A3F localization to HIV-1 cores. We found that one pair of leucines in each of A3F's C-terminal and N-terminal CD domains jointly determined the degree of localization of A3F into HIV-1 virion cores. These are A3F L306/L368 (C-terminal domain) and A3F L122/L184 (N-terminal domain). Alterations to one of these specific leucine residues in either of the two A3F CD domains (A3F L368A, L122A, and L184A) decreased core localization and diminished HIV restriction without changing virion packaging. Furthermore, double mutants in these leucine residues in each of A3F's two CD domains (A3F L368A plus L184A or A3F L368A plus L122A) still were packaged into virions but completely lost core localization and anti-HIV activity. HIV virion core localization of A3F is genetically separable from its virion packaging, and anti-HIV activity requires some core localization. IMPORTANCE: Specific leucine-leucine interactions are identified as necessary for A3F's core localization and anti-HIV activity but not for its packaging into virions. Understanding these signals may lead to novel strategies to enhance core localization that may augment effects of A3F against HIV and perhaps of other A3s against retroviruses, parvoviruses, and hepatitis B virus.


Assuntos
Citosina Desaminase/análise , Citosina Desaminase/genética , HIV-1/fisiologia , Montagem de Vírus , Linhagem Celular , Citosina Desaminase/imunologia , Análise Mutacional de DNA , Genes Reporter , HIV-1/química , HIV-1/imunologia , Humanos , Luciferases/análise , Modelos Moleculares , Mutagênese Sítio-Dirigida , Mutação de Sentido Incorreto , Coloração e Rotulagem , beta-Galactosidase/análise
6.
J Biol Chem ; 287(20): 16965-74, 2012 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-22451677

RESUMO

Human cytidine deaminases APOBEC3F (A3F) and APOBEC3G (A3G) inhibit human immunodeficiency virus type-1 (HIV-1) replication. In the absence of HIV-1 Vif, A3F and/or A3G are incorporated into assembling virions and exert antiviral functions in subsequently infected target cells. Encapsidation of A3F or A3G within the protease-matured virion core following their incorporation into virions is hypothesized to be important for the antiviral function of these proteins. In this report, we demonstrated that A3F was quantitatively encapsidated in the mature virion core. In distinct contrast, A3G was distributed both within and outside of the virion core. Analysis of a series of A3F-A3G chimeras comprised of exchanged N- and C-terminal deaminase domains identified a 14 amino acid segment in the A3F C-terminal deaminase domain that contributed to preferential encapsidation and anti-HIV activity. Amino acid residue L306 in this C-terminal segment was determined to be necessary, but not sufficient, for these effects. Amino acid residue W126 in the N-terminal deaminase domain was determined also to contribute to preferential encapsidation and antiviral activity of A3F. Analysis of the A3F (W126A L306A) double mutant revealed that both residues are required for full anti-HIV function. The results reported here advance our understanding of the mechanisms of A3F virion encapsidation and antiviral function and may lead to innovative strategies to inhibit HIV-1 replication.


Assuntos
Citosina Desaminase/metabolismo , HIV-1/fisiologia , Sinais Direcionadores de Proteínas , Vírion/metabolismo , Replicação Viral , Desaminase APOBEC-3G , Substituição de Aminoácidos , Citidina Desaminase/genética , Citidina Desaminase/metabolismo , Citosina Desaminase/genética , Células HEK293 , Humanos , Mutação de Sentido Incorreto , Estrutura Terciária de Proteína , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Vírion/genética
7.
Eur J Clin Pharmacol ; 65(11): 1081-8, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19779705

RESUMO

PURPOSE: P-glycoprotein limits the tissue penetration of many antiretroviral drugs. The aim of our study was to characterize the effects of the P-glycoprotein substrate cyclosporin A on T cell P-glycoprotein activity in human immunodeficiency virus-infected participants in the AIDS Clinical Trials Group study A5138. METHODS: We studied P-glycoprotein activity on CD4 and CD8 T cells in 16 participants randomized to receive oral cyclosporin A (n=9) or not (n=7) during initiation antiretroviral therapy (ART) that did not include protease or non-nucleoside reverse transcriptase inhibitors. RESULTS: CD4 T cell P-glycoprotein activity decreased by a median of 8 percentage points with cyclosporin A/ART (difference between cyclosporin A/ART vs. ART only, P= 0.001). Plasma trough cyclosporin A concentrations correlated with the change in P-glycoprotein activity in several T cell subsets. CONCLUSIONS: Oral cyclosporin A can inhibit peripheral blood CD4 T cell P-glycoprotein activity. Targeted P-glycoprotein inhibition may enhance the delivery of ART to T cells.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Terapia Antirretroviral de Alta Atividade , Linfócitos T CD4-Positivos/efeitos dos fármacos , Ciclosporina/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Infecções por HIV/tratamento farmacológico , Adulto , Fármacos Anti-HIV/farmacocinética , Fármacos Anti-HIV/uso terapêutico , Linfócitos T CD4-Positivos/enzimologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/enzimologia , Ciclosporina/sangue , Ciclosporina/farmacologia , Inibidores Enzimáticos/sangue , Inibidores Enzimáticos/farmacologia , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
Anesthesiology ; 109(6): 1092-9, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19034106

RESUMO

BACKGROUND: Loperamide, a potent opioid, has been used as an in vivo probe to assess P-glycoprotein activity at the blood-brain barrier, because P-glycoprotein inhibition allows loperamide to cross the blood-brain barrier and exert its central opioid effects. In humans, studies with nonselective and moderately potent inhibitors resulted in mild opioid effects but were confounded by the concurrent inhibition of loperamide's metabolism. The authors studied the effect of the highly selective, potent P-glycoprotein inhibitor tariquidar on loperamide's central opioid effects. METHODS: In a randomized, double-blind, crossover study, nine healthy subjects received on 2 study days oral loperamide (32 mg) followed by an intravenous infusion of either tariquidar (150 mg) or placebo. Central opioid effects (pupil diameter, sedation) were measured for 12 h, and blood samples were drawn up to 48 h after drug administration to determine plasma loperamide concentrations and ex vivo P-glycoprotein activity in T lymphocytes. Values for pupil diameter and loperamide concentrations were plotted over time, and the areas under the curves on the tariquidar and placebo study day were compared within each subject. RESULTS: Tariquidar did not significantly affect loperamide's central effects (median reduction in pupil diameter area under the curve, 6.9% [interquartile range, -1.4 to 12.1%]; P = 0.11) or plasma loperamide concentrations (P = 0.12) but profoundly inhibited P-glycoprotein in lymphocytes by 93.7% (95% confidence interval, 92.0-95.3%). CONCLUSION: These results suggest that despite full inhibition of lymphocyte P-glycoprotein, the selective P-glycoprotein inhibitor tariquidar does not potentiate loperamide's opioid brain effects in humans.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Analgésicos Opioides/administração & dosagem , Encéfalo/efeitos dos fármacos , Loperamida/administração & dosagem , Linfócitos/efeitos dos fármacos , Quinolinas/administração & dosagem , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/sangue , Adulto , Analgésicos Opioides/sangue , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Estudos Cross-Over , Método Duplo-Cego , Sinergismo Farmacológico , Feminino , Humanos , Loperamida/sangue , Linfócitos/sangue , Masculino , Pupila/efeitos dos fármacos , Pupila/fisiologia , Quinolinas/sangue , Adulto Jovem
9.
Virology ; 377(1): 49-53, 2008 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-18499212

RESUMO

The HIV-1 virion infectivity factor (Vif) is required during viral replication to inactivate the host cell anti-viral factor, APOBEC3G (A3G). Vif binds A3G and a Cullin5-ElonginBC E3 ubiquitin ligase complex which results in the proteasomal degradation of A3G. The Vif PPLP motif (amino acids 161-164) is essential for normal Vif function because mutations in this motif reduce the infectivity of virions produced in T-cells. In this report, we demonstrate that mutation of the Vif PPLP motif reduces Vif binding to A3G without affecting its interaction with ElonginC and Cullin5. We demonstrate that the failure of the Vif mutant to bind A3G resulted in A3G incorporation into assembling virions with loss of viral infectivity.


Assuntos
Citidina Desaminase/metabolismo , HIV-1/fisiologia , Produtos do Gene vif do Vírus da Imunodeficiência Humana/metabolismo , Desaminase APOBEC-3G , Motivos de Aminoácidos , Sequência de Aminoácidos , Sítios de Ligação/genética , Linhagem Celular , Proteínas Culina/química , Proteínas Culina/metabolismo , Citidina Desaminase/antagonistas & inibidores , Elonguina , Teste de Complementação Genética , HIV-1/genética , HIV-1/patogenicidade , Humanos , Complexos Multiproteicos , Mutação , Complexo de Endopeptidases do Proteassoma/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo , Virulência , Replicação Viral , Produtos do Gene vif do Vírus da Imunodeficiência Humana/química , Produtos do Gene vif do Vírus da Imunodeficiência Humana/genética
10.
Am J Ophthalmol ; 144(2): 309-10, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17659967

RESUMO

PURPOSE: To establish normative values of the retina in the pediatric population using optical coherence tomography (OCT). DESIGN: Prospective observational case control study. METHODS: Prospective study examining macular thickness and nerve fiber layer thickness in children with no ocular disease. After clinical examination, patients meeting the inclusion and exclusion criteria underwent OCT scanning. RESULTS: Thirty-two eyes were examined for macular thickness and 25 eyes for nerve fiber layer thickness. Normative values are found in the Table. The average foveal thickness for children is 221 microns vs 182 microns in adults. CONCLUSION: This study demonstrates normative values of retinal thickness and retinal nerve fiber layer (RNFL) thickness in the pediatric age group. Children have slightly thicker maculas than adults; the RNFL thickness is comparable to adults.


Assuntos
Retina/citologia , Tomografia de Coerência Óptica , Adolescente , Fatores Etários , Criança , Fóvea Central/citologia , Humanos , Estudos Prospectivos , Valores de Referência , Células Ganglionares da Retina/citologia
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