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1.
EClinicalMedicine ; 76: 102809, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39290640

RESUMO

Background: We aimed to study the clinical characteristics, myocardial injury, and longitudinal outcomes of COVID-19 vaccine-associated myocarditis (C-VAM). Methods: In this longitudinal retrospective observational cohort multicenter study across 38 hospitals in the United States, 333 patients with C-VAM were compared with 100 patients with multisystem inflammatory syndrome in children (MIS-C). We included patients ≤30 years of age with a clinical diagnosis of acute myocarditis after COVID-19 vaccination based on clinical presentation, abnormal biomarkers and/or cardiovascular imaging findings. Demographics, past medical history, hospital course, biochemistry results, cardiovascular imaging, and follow-up information from April 2021 to November 2022 were collected. The primary outcome was presence of myocardial injury as evidenced by late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) imaging. Findings: Patients with C-VAM were predominantly white (67%) adolescent males (91%, 15.7 ± 2.8 years). Their initial clinical course was more likely to be mild (80% vs. 23%, p < 0.001) and cardiac dysfunction was less common (17% vs. 68%, p < 0.0001), compared to MIS-C. In contrast, LGE on CMR was more prevalent in C-VAM (82% vs. 16%, p < 0.001). The probability of LGE was higher in males (OR 3.28 [95% CI: 0.99, 10.6, p = 0.052]), in older patients (>15 years, OR 2.74 [95% CI: 1.28, 5.83, p = 0.009]) and when C-VAM occurred after the first or second dose as compared to the third dose of mRNA vaccine. Mid-term clinical outcomes of C-VAM at a median follow-up of 178 days (IQR 114-285 days) were reassuring. No cardiac deaths or heart transplantations were reported until the time of submission of this report. LGE persisted in 60% of the patients at follow up. Interpretation: Myocardial injury at initial presentation and its persistence at follow up, despite a mild initial course and favorable mid-term clinical outcome, warrants continued clinical surveillance and long-term studies in affected patients with C-VAM. Funding: The U.S. Food and Drug Administration.

2.
Eur Heart J ; 44(34): 3278-3291, 2023 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-37592821

RESUMO

BACKGROUND AND AIMS: For patients with congenitally corrected transposition of the great arteries (ccTGA), factors associated with progression to end-stage congestive heart failure (CHF) remain largely unclear. METHODS: This multicentre, retrospective cohort study included adults with ccTGA seen at a congenital heart disease centre. Clinical data from initial and most recent visits were obtained. The composite primary outcome was mechanical circulatory support, heart transplantation, or death. RESULTS: From 558 patients (48% female, age at first visit 36 ± 14.2 years, median follow-up 8.7 years), the event rate of the primary outcome was 15.4 per 1000 person-years (11 mechanical circulatory support implantations, 12 transplantations, and 52 deaths). Patients experiencing the primary outcome were older and more likely to have a history of atrial arrhythmia. The primary outcome was highest in those with both moderate/severe right ventricular (RV) dysfunction and tricuspid regurgitation (n = 110, 31 events) and uncommon in those with mild/less RV dysfunction and tricuspid regurgitation (n = 181, 13 events, P < .001). Outcomes were not different based on anatomic complexity and history of tricuspid valve surgery or of subpulmonic obstruction. New CHF admission or ventricular arrhythmia was associated with the primary outcome. Individuals who underwent childhood surgery had more adverse outcomes than age- and sex-matched controls. Multivariable Cox regression analysis identified older age, prior CHF admission, and severe RV dysfunction as independent predictors for the primary outcome. CONCLUSIONS: Patients with ccTGA have variable deterioration to end-stage heart failure or death over time, commonly between their fifth and sixth decades. Predictors include arrhythmic and CHF events and severe RV dysfunction but not anatomy or need for tricuspid valve surgery.


Assuntos
Insuficiência Cardíaca , Transposição dos Grandes Vasos , Insuficiência da Valva Tricúspide , Disfunção Ventricular Direita , Adulto , Humanos , Feminino , Criança , Adulto Jovem , Pessoa de Meia-Idade , Masculino , Transposição das Grandes Artérias Corrigida Congenitamente , Estudos Retrospectivos , Transposição dos Grandes Vasos/complicações , Transposição dos Grandes Vasos/cirurgia , Insuficiência da Valva Tricúspide/complicações , Disfunção Ventricular Direita/complicações , Insuficiência Cardíaca/complicações
3.
J Am Coll Cardiol ; 80(10): 951-963, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-36049802

RESUMO

BACKGROUND: For patients with d-loop transposition of the great arteries (d-TGA) with a systemic right ventricle after an atrial switch operation, there is a need to identify risks for end-stage heart failure outcomes. OBJECTIVES: The authors aimed to determine factors associated with survival in a large cohort of such individuals. METHODS: This multicenter, retrospective cohort study included adults with d-TGA and prior atrial switch surgery seen at a congenital heart center. Clinical data from initial and most recent visits were obtained. The composite primary outcome was death, transplantation, or mechanical circulatory support (MCS). RESULTS: From 1,168 patients (38% female, age at first visit 29 ± 7.2 years) during a median 9.2 years of follow-up, 91 (8.8% per 10 person-years) met the outcome (66 deaths, 19 transplantations, 6 MCS). Patients experiencing sudden/arrhythmic death were younger than those dying of other causes (32.6 ± 6.4 years vs 42.4 ± 6.8 years; P < 0.001). There was a long duration between sentinel clinical events and end-stage heart failure. Age, atrial arrhythmia, pacemaker, biventricular enlargement, systolic dysfunction, and tricuspid regurgitation were all associated with the primary outcome. Independent 5-year predictors of primary outcome were prior ventricular arrhythmia, heart failure admission, complex anatomy, QRS duration >120 ms, and severe right ventricle dysfunction based on echocardiography. CONCLUSIONS: For most adults with d-TGA after atrial switch, progress to end-stage heart failure or death is slow. A simplified prediction score for 5-year adverse outcome is derived to help identify those at greatest risk.


Assuntos
Transposição das Grandes Artérias , Insuficiência Cardíaca , Transposição dos Grandes Vasos , Adulto , Transposição das Grandes Artérias/efeitos adversos , Artérias , Feminino , Seguimentos , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/etiologia , Humanos , Masculino , Estudos Retrospectivos , Transposição dos Grandes Vasos/cirurgia , Resultado do Tratamento
4.
Cureus ; 14(5): e24733, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35673316

RESUMO

Congenital diaphragmatic hernias (CDH) can induce life-threatening pulmonary hypertension and right heart failure. The patent ductus arteriosus (PDA) is often maintained in CDH to allow for decompression into the systemic circulation. However, if the PDA becomes hemodynamically significant, PDA closure may be indicated. Traditional methods rely on pharmacological closure. In this report, we document a rare transcatheter closure of a hemodynamically significant PDA.

5.
Clin Transl Sci ; 15(3): 619-625, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34713976

RESUMO

Junctional ectopic tachycardia (JET) is a potentially life-threatening postoperative arrhythmia in children with specific congenital heart defects and can contribute significantly to postoperative morbidity for at-risk populations. In adults, ß1-adrenergic receptor (ADRB1) and ß2-adrenergic receptor (ADRB2) genotypes have been associated with increased risk for arrhythmias. However, their association with arrhythmia risk in children is unknown. We aimed to test associations between ADRB1 and ADRB2 genotypes and postoperative JET in patients with congenital heart defects. Children who underwent cardiac surgery were genotyped for the ADRB1 p.Ser49Gly (rs1801252; c.145A>G), p.Arg389Gly (rs1801253; c.1165C>G), ADRB2 p.Arg16Gly (rs1042713; c.46A>G), and p.Glu27Gln (rs1042714; c.79G>C) polymorphisms. The occurrence of postoperative JET was assessed via cardiologist-interpreted electrocardiograms. Genotype associations with JET were analyzed via logistic regression, adjusted for clinical variables associated with JET, with separate analysis in patients not on a ß-blocker. Of the 343 children included (median age 8 months, 53% boys, 69% European ancestry), 45 (13%) developed JET. The Arg389Arg genotype was not significantly associated with JET in the overall population (odds ratio [OR] = 1.96, 95% confidence interval [CI] = 0.96-4.03, p = 0.064), but was nominally associated in patients not taking a ß-blocker (n = 324, OR = 2.25, 95% CI = 1.05-4.80. p = 0.034). None of the other variants were associated with JET. These data suggest that the ADRB1 Arg389Arg genotype may predict risk for JET following cardiac surgery in pediatric patients in the absence of ß-blockade. Whether treatment with a ß-blocker ameliorates this association requires further research.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Taquicardia Ectópica de Junção , Adulto , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Criança , Eletrocardiografia , Feminino , Genótipo , Humanos , Lactente , Masculino , Polimorfismo Genético , Taquicardia Ectópica de Junção/etiologia , Taquicardia Ectópica de Junção/genética
6.
Pediatrics ; 148(5)2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34389692

RESUMO

OBJECTIVES: In this study, we aimed to characterize the clinical presentation, short-term prognosis, and myocardial tissue changes as noted on cardiovascular magnetic resonance (CMR) or cardiac MRI in pediatric patients with coronavirus disease 2019 vaccination-associated myocarditis (C-VAM). METHODS: In this retrospective multicenter study across 16 US hospitals, patients <21 years of age with a diagnosis of C-VAM were included and compared with a cohort with multisystem inflammatory syndrome in children. Younger children with C-VAM were compared with older adolescents. RESULTS: Sixty-three patients with a mean age of 15.6 years were included; 92% were male. All had received a messenger RNA vaccine and, except for one, presented after the second dose. Four patients had significant dysrhythmia; 14% had mild left ventricular dysfunction on echocardiography, which resolved on discharge; 88% met the diagnostic CMR Lake Louise criteria for myocarditis. Myocardial injury as evidenced by late gadolinium enhancement on CMR was more prevalent in comparison with multisystem inflammatory syndrome in children. None of the patients required inotropic, mechanical, or circulatory support. There were no deaths. Follow-up data obtained in 86% of patients at a mean of 35 days revealed resolution of symptoms, arrhythmias, and ventricular dysfunction. CONCLUSIONS: Clinical characteristics and early outcomes are similar between the different pediatric age groups in C-VAM. The hospital course is mild, with quick clinical recovery and excellent short-term outcomes. Myocardial injury and edema are noted on CMR. Close follow-up and further studies are needed to understand the long-term implications and mechanism of these myocardial tissue changes.


Assuntos
Vacinas contra COVID-19/efeitos adversos , Miocardite/diagnóstico , Miocardite/etiologia , Adolescente , Técnicas de Imagem Cardíaca , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Prognóstico , Estudos Retrospectivos
7.
Echocardiography ; 36(10): 1930-1935, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31573698

RESUMO

Partial anomalous pulmonary venous connection is defined by one or more of the pulmonary veins draining to the heart into a location other than the left atrium. Depending on the location of the anomalous venous connection, they can be categorized as supracardiac, infracardiac, cardiac, and mixed types. In some cases, there is no hemodynamic consequence; in others, it can result in tricuspid regurgitation, right heart dilation, and pulmonary hypertension. Frequently, the reason for referral can be asymptomatic right heart dilation of unknown significance. Diagnosis is often difficult by transthoracic echocardiogram unless there is a high index of suspicion, and the appropriate views are obtained. Cardiac CT (computed tomography) or cardiac MRI (magnetic resonance imaging) can provide more precise anatomic detail as needed. The current article reviews the etiology and pathophysiology of partial anomalous pulmonary venous connection, and also reviews the current knowledge on their treatment.


Assuntos
Ecocardiografia/métodos , Imageamento por Ressonância Magnética/métodos , Veias Pulmonares/anormalidades , Síndrome de Cimitarra/diagnóstico por imagem , Síndrome de Cimitarra/fisiopatologia , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Feminino , Humanos , Veias Pulmonares/diagnóstico por imagem , Adulto Jovem
8.
World J Pediatr Congenit Heart Surg ; 10(5): 533-538, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31496399

RESUMO

Planning corrective and palliative surgery for patients who have complex congenital heart disease often relies on the assessment of cardiac anatomy using two-dimensional noninvasive cardiac imaging modalities (echocardiography, cardiac magnetic resonance imaging, and computed tomography scan). Advances in cardiac noninvasive imaging now include the use of three-dimensional (3D) reconstruction tools that produce 3D images and 3D printouts. There is scant evidence available in the literature as to what effect the availability of 3D printouts of complex congenital heart defects has on surgical outcomes. Surgical outcomes of study subjects with a 3D cardiac printout available and their paired control subject without a 3D cardiac printout available were compared. We found a trend toward shorter surgical times in the study group who had the benefit of 3D models, but no statistical significance was found for bypass time, cross-clamp time, total time, length of stay, or respiratory support. These preliminary results support the proposal that 3D modeling be made readily available to congenital cardiac surgery teams, for use in patients with the most complex congenital heart disease.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias Congênitas/cirurgia , Imageamento Tridimensional , Impressão Tridimensional , Pré-Escolar , Feminino , Coração/diagnóstico por imagem , Humanos , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Modelos Cardiovasculares , Projetos Piloto , Tomografia Computadorizada por Raios X
9.
Aging Dis ; 10(1): 12-22, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30705764

RESUMO

Stroke occurs mostly in patients with advanced age. Elderly patients have a less favorable prognosis compared with young adult patients. To understand the underlying mechanisms, we tested our hypothesis that an increased inflammatory response to acute ischemic injury in old stroke mice leads to more severe brain damage and behavioral dysfunction. An ischemic stroke model was created in 2- and 12-month-old C57BL/6 mice through permanent occlusion of the left distal middle cerebral artery (dMCAO). Infarct/atrophy volumes were quantified by staining the brain sections with Cresyl Violet. Sensorimotor function was assessed using the corner test and adhesive removal test. Quantification of CD68+ cells in the peri-infarct region was performed at 1, 3 and 14 days after dMCAO. Interleukin-6 (IL-6), interleukin-1 ß (IL-1ß) and vascular endothelial growth factor (VEGF) levels in the ischemic brain tissue were measured using ELISA. Western blot was used to determine the expression levels of tight junction proteins, claudin-5 and zonula occludens (ZO)-1. Blood-brain barrier permeability was measured by Evans blue (EB) extravasation. Gelatinase B (MMP-9, type IV collagenase) was measured by gel zymography. Compared to 2-month-old mice, 12-month-old mice had more severe behavioral deficits at both the acute and chronic stages of stroke. Compared with the 2-month-old mice, 12-month-old mice had larger infarct/atrophy volumes at 1 and 14 days after dMCAO, higher levels of IL-6 and IL-1ß, higher MMP9 activity, and lower levels of claudin-5 and ZO-1 at 1 and 3 days after dMCAO. 12-month-old mice also had more CD68+ cells in the peri-infarct region at 1, 3 and 14 days after dMCAO and more EB leakage at 3 days after dMCAO. A higher inflammatory response at the acute stage of ischemic stroke in old mice is associated with more severe neuronal injury and long-term behavioral dysfunction.

10.
JACC Case Rep ; 1(4): 523-525, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34316869

RESUMO

The natural history of tetralogy of Fallot depends on whether a transannular pulmonary valve patch or shunt surgery was necessary in infancy. This case illustrates the feasibility of cardiac rest on extracorporeal membranous oxygenation for a very ill adult with conduit endocarditis who received a right ventricle-to-pulmonary artery valveless conduit for later transcatheter pulmonary valve replacement. (Level of Difficulty: Advanced.).

11.
Ophthalmic Genet ; 39(3): 373-376, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29336632

RESUMO

BACKGROUND: Möbius syndrome is a rare congenital condition which presents not merely with 6th and 7th nerve palsies, but involves gaze paresis associated with craniofacial, limb, and other abnormalities. Heterogeneity is well known in patients with Möbius syndrome and rather than being of familial inheritance based on rare cases, it is much more recognized as a sporadic syndrome. We report an infant with features of congenital Möbius syndrome associated with cardiac rhabdomyomas in the absence of tuberous sclerosis. MATERIALS AND METHODS: Observational case report of an infant seen at a tertiary academic center with genetic testing, ophthalmic, neurological, and cardiac clinical examination and imaging. RESULTS: A newborn baby boy at birth was seen with multiple congenital craniofacial malformations, and respiratory distress. He was noted to have micrognathia, retrognathia, wide nasal bridge, low set ears, high arched palate, nonreducing bilateral talipes equinovarus and bilateral large angle esotropia with -4 abduction deficit and facial palsy, findings suggestive of Möbius Syndrome. MRI of the brain was unremarkable except for syringomyelia in the cervical spine. Echocardiography showed two cardiac rhabdomyomas in the right ventricle and ulltrasound of the abdomen showed mild right hydroneprosis. Cytogenetics revealed segmental loss at 21q21.2. Testing for tuberous sclerosis was negative for deletion or duplications of genes TSC1 and TSC2. CONCLUSION: This case highlights the rare co-occurrence of cardiac rhabdomyomas with Möbius syndrome and new segmental loss at 21q21.2 on genetic testing. Findings could indicate not a "suggestion of Möbius", but rather the syndrome itself in association with cardiac defects.


Assuntos
Neoplasias Cardíacas/diagnóstico , Síndrome de Möbius/diagnóstico , Rabdomioma/diagnóstico , Testes Genéticos , Neoplasias Cardíacas/complicações , Neoplasias Cardíacas/genética , Humanos , Recém-Nascido , Masculino , Síndrome de Möbius/complicações , Síndrome de Möbius/genética , Rabdomioma/complicações , Rabdomioma/genética
12.
Eur J Cardiothorac Surg ; 53(1): 284-285, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28958060

RESUMO

Penetrating cardiac injuries with extensive intracardiac components and minimal epicardial components are a rare presentation. A 31-year-old male presented with complex mitral valve and ventricular septal injuries with partial atrioventricular disruption but with hardly visible epicardial injuries; the patient's presentation, progression of injuries and successful management are discussed.


Assuntos
Valva Mitral/lesões , Septo Interventricular/lesões , Ferimentos Perfurantes/cirurgia , Adulto , Humanos , Masculino , Valva Mitral/cirurgia , Septo Interventricular/cirurgia , Ferimentos Perfurantes/diagnóstico
13.
Eur J Med Chem ; 54: 919-24, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22703844

RESUMO

Huanglongbing is the most devastating disease of citrus caused by Candidatus Liberibacter asiaticus (Las). In the present study, we report the discovery of novel small molecule inhibitors against SecA ATPase of Las by using structure based design methods. We built the homology model of SecA protein structure of Las based on the SecA of Escherichia coli. The model was used for in-silico screening of commercially available compounds from ZINC database. Using the glide flexible molecular docking method, twenty structures were chosen for in vitro studies. Five compounds were found to inhibit the ATPase activity of SecA of Las at nano molar concentrations and showed antimicrobial activities against Agrobacterium tumefaciens with MBC ranging from 128 to 256 µg/mL. These compounds appear to be suitable as lead compounds for further development of antimicrobial compounds against Las.


Assuntos
Adenosina Trifosfatases/antagonistas & inibidores , Antibacterianos/química , Antibacterianos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Desenho de Fármacos , Rhizobiaceae/enzimologia , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Adenosina Trifosfatases/química , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/metabolismo , Agrobacterium tumefaciens/efeitos dos fármacos , Antibacterianos/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Proteínas de Membrana Transportadoras/química , Proteínas de Membrana Transportadoras/metabolismo , Simulação de Acoplamento Molecular , Conformação Proteica , Rhizobiaceae/efeitos dos fármacos , Canais de Translocação SEC , Proteínas SecA , Homologia de Sequência de Aminoácidos , Bibliotecas de Moléculas Pequenas/metabolismo
14.
Int J Mol Med ; 29(1): 61-4, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21947232

RESUMO

Plasminogen activator inhibitor type 1 (PAI-1) is a serpin protein, a natural inhibitor of urokinase (uPA) and tissue plasminogen activators (tPA). By inhibiting uPA it can block growth of the cancer tumors by suppressing angiogenesis, while when acting on tPA in the blood it can avert conversion of plasminogen to plasmin preventing lysis of the clot. Furthermore, blocking PAI-1 activity can protect against thrombosis. Thus PAI-1 makes great impact on human homeostasis and is desirable for clinical application. Wild-type PAI-1 (wt-PAI-1) has a short span of activity with a t1/2 of ~2 h, being spontaneously converted into a latent form. An enormous effort has been made to create a more stable molecule with >600 PAI-1 variants constructed to study its structure-function relationship. In the present study, we evaluate the structure of the active recombinant VLHL-PAI-1 (very long half life, active >700 h) which is glycosylated similarly to wt-PAI-1 at N232 and N288, with the extended reactive center loop, intact engineered -S-S-bridge (Q174C, G323C) that precludes latency without affecting structure, and can be controlled by a reducing agent to terminate activity at will. We have already proven its usefulness to control cancer in human cancer cells, as well as preventing clot lysis in human whole blood and plasma and in a mouse model. Our results demonstrate the potential therapeutic applications (topical or systemic) of this protein in the treatment of cancer, for the trauma patients to ward off an excessive blood loss, or for people with the PAI-1 deficiency, especially during surgery.


Assuntos
Inibidor 1 de Ativador de Plasminogênio/química , Proteínas Recombinantes/química , Animais , Linhagem Celular , Cristalografia por Raios X , Dissulfetos , Glicosilação , Humanos , Camundongos , Modelos Moleculares , Mutação , Inibidor 1 de Ativador de Plasminogênio/farmacocinética , Polissacarídeos , Estabilidade Proteica , Proteínas Recombinantes/farmacocinética
15.
J Med Chem ; 54(24): 8563-73, 2011 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-22047606

RESUMO

The androgen receptor (AR) is the best studied drug target for the treatment of prostate cancer. While there are a number of drugs that target the AR, they all work through the same mechanism of action and are prone to the development of drug resistance. There is a large unmet need for novel AR inhibitors which work through alternative mechanism(s). Recent studies have identified a novel site on the AR called binding function 3 (BF3) that is involved into AR transcriptional activity. In order to identify inhibitors that target the BF3 site, we have conducted a large-scale in silico screen followed by experimental evaluation. A number of compounds were identified that effectively inhibited the AR transcriptional activity with no obvious cytotoxicity. The mechanism of action of these compounds was validated by biochemical assays and X-ray crystallography. These findings lay a foundation for the development of alternative or supplementary therapies capable of combating prostate cancer even in its antiandrogen resistant forms.


Assuntos
Bases de Dados Factuais , Relação Quantitativa Estrutura-Atividade , Receptores Androgênicos/química , Bibliotecas de Moléculas Pequenas , Antagonistas de Androgênios/química , Antagonistas de Androgênios/farmacologia , Sítios de Ligação , Linhagem Celular Tumoral , Cristalografia por Raios X , Humanos , Ligantes , Modelos Moleculares , Mutação , Conformação Proteica , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Transcrição Gênica
16.
Bioorg Med Chem Lett ; 21(14): 4183-8, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21684161

RESUMO

Candidatus Liberibacter asiaticus is the causal agent of Huanglongbing (HLB) disease of citrus. Current management practices have not been able to control HLB and stop the spread of HLB. The current study is focused on screening small molecule inhibitors against SecA protein of Ca. L. asiaticus. Homology modeling, structure based virtual screening and molecular docking methods have been used to find the novel inhibitory compounds against SecA activity at ATP binding region. At 20µm 17 compounds showed >50% inhibition and four compounds had more than 65% inhibition. The most active compound has IC(50) value of 2.5µM. The differences between the activities of the compounds are explained by their inter-molecular interactions at ATP binding site.


Assuntos
Adenosina Trifosfatases/antagonistas & inibidores , Proteínas de Bactérias/antagonistas & inibidores , Rhizobiaceae/metabolismo , Bibliotecas de Moléculas Pequenas/química , Adenosina Trifosfatases/metabolismo , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Simulação por Computador , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Proteínas de Membrana Transportadoras/metabolismo , Canais de Translocação SEC , Proteínas SecA , Bibliotecas de Moléculas Pequenas/farmacologia
17.
Nucleic Acids Res ; 39(7): 2534-47, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21131274

RESUMO

MicroRNA (miRNA)-mediated gene regulation has become a major focus in many biological processes. GW182 and its long isoform TNGW1 are marker proteins of GW/P bodies and bind to Argonaute proteins of the RNA induced silencing complex. The goal of this study is to further define and distinguish the repression domain(s) in human GW182/TNGW1. Two non-overlapping regions, Δ12 (amino acids 896-1219) containing the Ago hook and Δ5 (amino acids 1670-1962) containing the RRM, both induced comparable silencing in a tethering assay. Mapping data showed that the RRM and its flanking sequences in Δ5, but not the Ago hook in Δ12, were important for silencing. Repression mediated by Δ5 or Δ12 was not differentially affected when known endogenous repressors RCK/p54, GW182/TNGW1, TNRC6B were depleted. Transfected Δ5, but not Δ12, enhanced Ago2-mediated repression in a tethering assay. Transfected Δ12, but not Δ5, released endogenous miRNA reporter silencing without affecting siRNA function. Alanine substitution showed that GW/WG motifs in Δ12 (Δ12a, amino acids 896-1045) were important for silencing activity. Although Δ12 appeared to bind PABPC1 more efficiently than Δ5, neither Δ5 nor Δ12 significantly enhanced reporter mRNA degradation. These different functional characteristics of Δ5 and Δ12 suggest that their roles are distinct, and possibly dynamic, in human GW182-mediated silencing.


Assuntos
Autoantígenos/química , Biossíntese de Proteínas , Interferência de RNA , Proteínas de Ligação a RNA/química , Motivos de Aminoácidos , Proteínas Argonautas , Autoantígenos/genética , Autoantígenos/metabolismo , Linhagem Celular , Fator de Iniciação 2 em Eucariotos/metabolismo , Humanos , MicroRNAs/metabolismo , Proteína I de Ligação a Poli(A)/metabolismo , Estrutura Terciária de Proteína , Estabilidade de RNA , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Deleção de Sequência
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