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1.
Sci Transl Med ; 14(670): eabn7336, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36350986

RESUMO

Chimeric antigen receptor (CAR) T cells have not induced meaningful clinical responses in solid tumors. Loss of T cell stemness, poor expansion capacity, and exhaustion during prolonged tumor antigen exposure are major causes of CAR T cell therapeutic resistance. Single-cell RNA-sequencing analysis of CAR T cells from a first-in-human trial in metastatic prostate cancer identified two independently validated cell states associated with antitumor potency or lack of efficacy. Low expression of PRDM1, encoding the BLIMP1 transcription factor, defined highly potent TCF7 [encoding T cell factor 1 (TCF1)]-expressing CD8+ CAR T cells, whereas enrichment of HAVCR2 [encoding T cell immunoglobulin and mucin-domain containing-3 (TIM-3)]-expressing CD8+ T cells with elevated PRDM1 was associated with poor outcomes. PRDM1 knockout promoted TCF7-dependent CAR T cell stemness and proliferation, resulting in marginally enhanced leukemia control in mice. However, in the setting of PRDM1 deficiency, a negative epigenetic feedback program of nuclear factor of activated T cells (NFAT)-driven T cell dysfunction was identified. This program was characterized by compensatory up-regulation of NR4A3 and other genes encoding exhaustion-related transcription factors that hampered T cell effector function in solid tumors. Dual knockout of PRDM1 and NR4A3 skewed CAR T cell phenotypes away from TIM-3+CD8+ and toward TCF1+CD8+ to counter exhaustion of tumor-infiltrating CAR T cells and improve antitumor responses, effects that were not achieved with PRDM1 and NR4A3 single knockout alone. These data underscore dual targeting of PRDM1 and NR4A3 as a promising approach to advance adoptive cell immuno-oncotherapy.


Assuntos
Neoplasias , Receptores de Esteroides , Masculino , Humanos , Camundongos , Animais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Linfócitos T CD8-Positivos , Imunoterapia Adotiva/métodos , Receptor Celular 2 do Vírus da Hepatite A/genética , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Neoplasias/patologia , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Receptores de Esteroides/metabolismo , Receptores dos Hormônios Tireóideos/metabolismo , Proteínas do Tecido Nervoso/metabolismo
2.
J Matern Fetal Neonatal Med ; 35(25): 7093-7101, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34210207

RESUMO

Objective: To determine whether vaginal progesterone reduces spontaneous preterm birth (sPTB) before 37 weeks in asymptomatic high-risk women with a singleton pregnancy and normal mid-gestation cervical length.Study design: Databases were searched (from inception to December 2020) with the search terms "progesterone" and "premature birth" or "preterm birth". Studies were screened and included if they assessed vaginal progesterone compared to placebo in women with normal cervical length. Data were pooled and synthesized in a meta-analysis using a random effects model.Data sources: MEDLINE and Embase databases.Study synthesis: Following PRISMA screening guidelines, data from 1127 women across three studies were available for synthesis. All studies had low risk of bias and were of high quality. The primary outcome was sPTB <37 weeks, with secondary outcomes of sPTB <34 weeks. Vaginal progesterone did not significantly reduce sPTB before 37 weeks, or before 34 weeks with a relative risk (RR) of 0.76 (95% CI 0.37-1.55, p = .45) and 0.51 (95% CI 0.12-2.13, p = .35), respectively.Conclusions: Vaginal progesterone does not decrease the risk of sPTB in high-risk singleton pregnancies with a normal mid-gestation cervical length.


Assuntos
Nascimento Prematuro , Progesterona , Gravidez , Recém-Nascido , Feminino , Humanos , Administração Intravaginal , Nascimento Prematuro/prevenção & controle , Colo do Útero/diagnóstico por imagem , Gravidez de Alto Risco , Medida do Comprimento Cervical
3.
ACS Appl Mater Interfaces ; 13(51): 60852-60864, 2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-34914872

RESUMO

Cerium oxide nanoparticles (CeONP), having potent antioxidant properties, are highly promising nanomaterials for treatment of diseases in which oxidative stress from excessive reactive oxygen species (ROS) plays a critical role in the pathogenesis and progression. However, most previously reported CeONP formulations were not efficiently cleared from the body, precluding their clinical translation. Herein, we report ultrasmall CeONP that can mitigate activation of macrophages and subsequent acute inflammation. It is found that these CeONP can effectively scavenge reactive species, inhibit macrophage activation, and minimize their recruitment and infiltration to the inflammation site, which lead to alleviation of edema and pain hypersensitivity. Moreover, we demonstrate that CeONP can be effectively excreted from the body within 24 h of systemic administration, minimizing long-term toxicity concerns. Altogether, our findings suggest that CeONP may be explored as both antioxidant and anti-inflammatory agents that can reduce acute inflammation with a better safety profile than existing nanoparticles.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antioxidantes/farmacologia , Materiais Biocompatíveis/farmacologia , Cério/farmacologia , Inflamação/tratamento farmacológico , Nanopartículas/química , Doença Aguda , Animais , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Antioxidantes/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Cério/química , Ácido Cítrico/química , Edema/tratamento farmacológico , Edema/metabolismo , Adjuvante de Freund , Humanos , Inflamação/metabolismo , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Masculino , Teste de Materiais , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Dor/tratamento farmacológico , Dor/metabolismo
4.
Ultrasound Obstet Gynecol ; 58(5): 688-697, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32851709

RESUMO

OBJECTIVES: Pre-eclampsia (PE) causes substantial maternal and neonatal mortality and morbidity. In addition to the personal impact on women, children and their families, PE has a significant economic impact on our society. Recent research suggests that a first-trimester multivariate model is highly predictive of preterm (< 37 weeks' gestation) PE and can be combined successfully with targeted prophylaxis (low-dose aspirin), resulting in an 80% reduction in prevalence of disease. The aim of this study was to examine the potential health outcomes and cost implications following introduction of first-trimester prediction and prevention of preterm PE within a public healthcare setting, compared with usual care, and to conduct a cost-effectiveness analysis to inform health-service decisions regarding implementation of such a program. METHODS: A decision-analytic model was used to compare usual care with the proposed first-trimester screening intervention within the obstetric population (n = 6822) attending two public hospitals within a metropolitan district health service in New South Wales, Australia, between January 2015 and December 2016. The model, applied from early pregnancy, included exposure to a variety of healthcare professionals and addressed type of risk assessment (usual care or first-trimester screening) and use of (compliance with) low-dose aspirin prescribed prophylactically for prevention of PE. All pathways culminated in six possible health outcomes, ranging from no PE to maternal death. Results were presented as the number of cases of PE gained/avoided and the incremental increase/decrease in economic costs arising from the intervention compared with usual care. Significant assumptions were tested in sensitivity/uncertainty analyses. RESULTS: The intervention produced, across all gestational ages, 31 fewer cases of PE and reduced aggregate economic health-service costs by 1 431 186 Australian dollars over the 2-year period. None of the tested iterations of uncertainty analyses reported additional cases of PE or higher economic costs. The new intervention based on first-trimester screening dominated usual care. CONCLUSION: This cost-effectiveness analysis demonstrated a reduction in prevalence of preterm PE and substantial cost savings associated with a population-based program of first-trimester prediction and prevention of PE, and supports implementation of such a policy. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Regras de Decisão Clínica , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/economia , Diagnóstico Pré-Natal/economia , Adulto , Análise Custo-Benefício , Feminino , Implementação de Plano de Saúde , Humanos , New South Wales/epidemiologia , Pré-Eclâmpsia/epidemiologia , Valor Preditivo dos Testes , Gravidez , Primeiro Trimestre da Gravidez , Nascimento Prematuro/diagnóstico , Nascimento Prematuro/economia , Nascimento Prematuro/epidemiologia , Diagnóstico Pré-Natal/métodos , Prevalência , Avaliação de Programas e Projetos de Saúde , Medição de Risco
5.
Physiol Genomics ; 51(3): 90-96, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30707046

RESUMO

Acute kidney injury (AKI) is an increasing clinical problem that is associated with chronic kidney disease progression. Cannabinoid receptor 2 (CB2) activation has been shown to mitigate some of the deleterious tubular effects due to AKI, but its role on the renal vasculature has not been fully described. In this study, we investigated the effects of our novel CB2 receptor agonist, SMM-295, on renal vasculature by assessing cortical perfusion with laser Doppler flowmetry and changes in luminal diameter with isolated afferent arterioles. In this study, intravenously infused SMM-295 (6 mg/kg) significantly increased cortical renal perfusion (13.8 ± 0.6%; P < 0.0001; n = 7) compared with vehicle (0.1 ± 1.5%; n = 10) normalized to baseline values in anesthetized C57BL/6J mice. This effect was not dependent upon activation of the CB1 receptor (met-anandamide; 6 mg/kg iv) and was predominantly abolished in Cnr2 knockout mice with SMM-295 (6 mg/kg iv). Ablation of the renal afferent nerves with capsaicin blocked the SMM-295-dependent increase in renal cortical perfusion, and the increased renal blood flow was not dependent upon products synthesized by cyclooxygenase or nitric oxide synthase. The increased renal perfusion by CB2 receptor activation is also attributed to a direct vascular effect, since SMM-295 (5 µM) engendered a significant 37 ± 7% increase ( P < 0.0001; n = 4) in luminal diameters of norepinephrine-preconstricted afferent arterioles. These data provide new insight into the potential benefit of SMM-295 by activating vascular and nonvascular CB2 receptors to promote renal vasodilation, and provide a new therapeutic target to treat renal injuries that impact renal blood flow dynamics.


Assuntos
Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/metabolismo , Receptor CB2 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/metabolismo , Circulação Renal/efeitos dos fármacos , Vasodilatadores/uso terapêutico , Animais , Ácidos Araquidônicos/administração & dosagem , Ácidos Araquidônicos/uso terapêutico , Agonistas de Receptores de Canabinoides/administração & dosagem , Agonistas de Receptores de Canabinoides/uso terapêutico , Modelos Animais de Doenças , Endocanabinoides/administração & dosagem , Endocanabinoides/uso terapêutico , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Técnicas de Inativação de Genes , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico Sintase/metabolismo , Alcamidas Poli-Insaturadas/administração & dosagem , Alcamidas Poli-Insaturadas/uso terapêutico , Prostaglandina-Endoperóxido Sintases/metabolismo , Receptor CB1 de Canabinoide/agonistas , Receptor CB1 de Canabinoide/metabolismo , Receptor CB2 de Canabinoide/genética , Vasodilatação/efeitos dos fármacos , Vasodilatadores/administração & dosagem
6.
Vet Rec ; 179(16): 412-413, 2016 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-27770094

RESUMO

Adopting the concept of One Welfare could help to improve animal welfare and human wellbeing worldwide, argue Rebeca García Pinillos, Michael Appleby, Xavier Manteca, Freda Scott-Park, Charles Smith and Antonio Velarde.


Assuntos
Bem-Estar do Animal/organização & administração , Comportamento Cooperativo , Saúde Global , Animais , Humanos
8.
Bioinspir Biomim ; 10(5): 055008, 2015 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-26440578

RESUMO

Digital implementations of control laws typically involve discretization with respect to both time and space, and a control law that can achieve a task at coarser levels of discretization can be said to require less control attention, and also reduced implementation costs. One means of quantitatively capturing the attention of a control law is to measure the rate of change of the control with respect to changes in state and time. In this paper we present an attention-minimizing control law for ball catching and other target tracking tasks based on Brockett's attention criterion. We first highlight the connections between this attention criterion and some well-known principles from human motor control. Under the assumption that the optimal control law is the sum of a linear time-varying feedback term and a time-varying feedforward term, we derive an LQR-based minimum attention tracking control law that is stable, and obtained efficiently via a finite-dimensional optimization over the symmetric positive-definite matrices. Taking ball catching as our primary task, we perform numerical experiments comparing the performance of the various control strategies examined in the paper. Consistent with prevailing theories about human ball catching, our results exhibit several familiar features, e.g., the transition from open-loop to closed-loop control during the catching movement, and improved robustness to spatiotemporal discretization. The presented control laws are applicable to more general tracking problems that are subject to limited communication resources.


Assuntos
Atenção/fisiologia , Beisebol/fisiologia , Biomimética/métodos , Modelos Neurológicos , Percepção de Movimento/fisiologia , Robótica/métodos , Algoritmos , Braço/fisiologia , Desempenho Atlético/fisiologia , Simulação por Computador , Desenho Assistido por Computador , Retroalimentação Fisiológica/fisiologia , Humanos , Robótica/instrumentação
9.
Ultrasound Obstet Gynecol ; 46(4): 419-23, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25678383

RESUMO

OBJECTIVE: To examine the effect of a combination of screening and treatment with low-dose aspirin on the prevalence of early-onset pre-eclampsia (PE). METHODS: This was a retrospective analysis of two consecutive cohorts of women screened for early PE. The first cohort was observed to determine whether algorithms developed to screen for PE at 11 to 13 + 6 weeks' gestation could be applied to our population. High-risk women in the second cohort were advised on their risk and offered aspirin (150 mg at night), with treatment starting immediately after screening. The prevalence of early PE and the proportion of women with PE delivering at 34-37 weeks' gestation were compared between the cohorts. RESULTS: In the observational and interventional cohorts, 3066 and 2717 women, respectively, were screened. There were 12 (0.4%) cases of early PE in the observational cohort and one (0.04%) in the interventional cohort (P < 0.01). Among all women with PE delivering before 37 weeks, 25 (0.83%) were in the observational cohort and 10 (0.37%) in the interventional cohort (P = 0.03). CONCLUSIONS: A strategy of first-trimester screening for early PE coupled with prescription of aspirin to the high-risk group appears to be effective in reducing the prevalence of early PE.


Assuntos
Aspirina/administração & dosagem , Inibidores da Agregação Plaquetária/administração & dosagem , Pré-Eclâmpsia/prevenção & controle , Adulto , Austrália/epidemiologia , Estudos de Coortes , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/diagnóstico por imagem , Pré-Eclâmpsia/epidemiologia , Valor Preditivo dos Testes , Gravidez , Resultado da Gravidez , Primeiro Trimestre da Gravidez , Estudos Retrospectivos , Fatores de Risco , Ultrassonografia Doppler de Pulso/métodos
10.
J Vet Intern Med ; 27(5): 1136-42, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24033421

RESUMO

BACKGROUND: Dogs with hyperadrenocorticism are at risk of thromboembolic disease, which might be caused by an underlying hypercoagulable state. HYPOTHESIS/OBJECTIVES: To assess hemostatic function in dogs with ACTH-dependent hyperadrenocorticism (ADHAC) before and after treatment. ANIMALS: Nineteen dogs with ADHAC and 40 normal dogs. METHODS: Prospective, observational study. Dogs with ADHAC were recruited from the referral hospital patient population; normal dogs were recruited from staff and students at the study's institution. Hemostasis was assessed before and at 3 and 6 months after treatment with trilostane (T0, T3, T6) by kaolin-activated thrombelastography with platelet mapping (TEG-PM), prothrombin time, activated partial thromboplastin time, fibrinogen concentration, and antithrombin activity (AT). RESULTS: Dogs with ADHAC had statistically significantly increased α-angle (P < .01) and maximum amplitude (MA)(thrombin) (P < .01) on TEG-PM, and significantly decreased κ (P < .005) at T0, T3, and T6. Platelet count (P < .001) and fibrinogen concentration (P < .001), but not AT activity, were increased in dogs with ADHAC at T0, T3, and T6. CONCLUSIONS AND CLINICAL IMPORTANCE: Dogs with ADHAC have thrombelastographic evidence of hypercoagulability and remained hypercoagulable during treatment. AT deficiency does not appear to be involved in the pathogenesis of hypercoagulability in this population.


Assuntos
Doenças do Cão/etiologia , Hiperaldosteronismo/veterinária , Trombofilia/veterinária , Animais , Análise Química do Sangue , Doenças do Cão/sangue , Doenças do Cão/patologia , Cães , Hiperaldosteronismo/complicações , Hiperaldosteronismo/patologia , Tromboelastografia/veterinária , Trombofilia/sangue , Trombofilia/complicações , Trombofilia/patologia
11.
Cell ; 153(3): 614-27, 2013 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-23622245

RESUMO

Protein degradation by the ubiquitin-proteasome system is central to cell homeostasis and survival. Defects in this process are associated with diseases such as cancer and neurodegenerative disorders. The 26S proteasome is a large protease complex that degrades ubiquitinated proteins. Here, we show that ADP-ribosylation promotes 26S proteasome activity in both Drosophila and human cells. We identify the ADP-ribosyltransferase tankyrase (TNKS) and the 19S assembly chaperones dp27 and dS5b as direct binding partners of the proteasome regulator PI31. TNKS-mediated ADP-ribosylation of PI31 drastically reduces its affinity for 20S proteasome α subunits to relieve 20S repression by PI31. Additionally, PI31 modification increases binding to and sequestration of dp27 and dS5b from 19S regulatory particles, promoting 26S assembly. Inhibition of TNKS by either RNAi or a small-molecule inhibitor, XAV939, blocks this process to reduce 26S assembly. These results unravel a mechanism of proteasome regulation that can be targeted with existing small-molecule inhibitors.


Assuntos
Drosophila melanogaster/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Tanquirases/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Proteínas de Transporte/metabolismo , Proteínas de Drosophila/metabolismo , Células HEK293 , Humanos , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Alinhamento de Sequência
13.
Aust Vet J ; 89(3): 82-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21323655

RESUMO

BACKGROUND: Studies of avian trichomoniasis in the literature are limited to some extent, often being confined to a single bird species or group of species within a bird Order. Some incidence studies have been reported for free-living birds, and occasionally for captive birds. Very few reports describe the prevalence and types of lesions seen for a wide range of bird species, especially from a clinical perspective. METHODS: Retrospective study of avian practice records from a 10-year period. Emphasis on the types of presentations and relative prevalence of trichomoniasis in a variety of captive and free-living bird species encountered in Australian avian practice. RESULTS: The occurrence of trichomoniasis in several novel species (lorikeets, corvids and a cuckoo species), plus its distinctive presentation in southern boobook owls (Ninox boobook), is documented. CONCLUSION: Trichomoniasis should be a differential diagnosis for birds presenting with regurgitation or upper gastrointestinal abscesses, even if motile trichomonads are not found in wet preparations from crop washes or lesions.


Assuntos
Doenças das Aves/epidemiologia , Doenças das Aves/patologia , Tricomoníase/veterinária , Animais , Animais Selvagens , Austrália/epidemiologia , Aves , Feminino , Masculino , Prevalência , Estudos Retrospectivos , Especificidade da Espécie , Tricomoníase/epidemiologia , Tricomoníase/patologia
14.
Aust Vet J ; 87(6): 249-52, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19489784

RESUMO

Two young adult male castrated German Shepherd Dogs were referred for evaluation of intermittent episodes of hindlimb pain. Physical examination suggested lumbosacral stenosis, and plain radiographs and computed tomography revealed lesions consistent with sacral osteochondrosis. One dog had osteochondral fragments removed surgically; the other was managed conservatively. The surgically treated dog had complete resolution of clinical signs whereas the dog managed conservatively had repeated episodes of mild pain and received one short course of non-steroidal anti-inflammatory medication in 18 months. Sacral osteochondrosis has not been previously reported in Australia.


Assuntos
Doenças do Cão/tratamento farmacológico , Doenças do Cão/cirurgia , Sacro , Osteocondrose da Coluna Vertebral/veterinária , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Doenças do Cão/diagnóstico por imagem , Cães , Membro Posterior , Masculino , Dor/diagnóstico , Dor/etiologia , Dor/veterinária , Sacro/diagnóstico por imagem , Osteocondrose da Coluna Vertebral/diagnóstico por imagem , Osteocondrose da Coluna Vertebral/tratamento farmacológico , Osteocondrose da Coluna Vertebral/cirurgia , Tomografia Computadorizada por Raios X/veterinária , Resultado do Tratamento
15.
Aust Vet J ; 87(1): 63-5, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19178482

RESUMO

A nestling Derbyan parrot (Psittacula derbiana) was presented with unusual subcutaneous swellings of the thigh regions, and poor growth. Histological examination revealed actinomycetous bacteria associated with multifocal systemic granulomas. The clinical and pathological findings of the case are presented, and some relevant aspects of actinomycetous bacterial infections in mammals and birds are discussed. Although granulomatous disease is encountered at times in avian species, the actinomycetous bacteria (Nocardia and Actinomyces spp.) have rarely been reported in association with multifocal granulomatous disease in birds.


Assuntos
Actinomicose/veterinária , Doenças das Aves/diagnóstico , Granuloma/veterinária , Nocardiose/veterinária , Papagaios/microbiologia , Actinomyces/isolamento & purificação , Actinomicose/diagnóstico , Actinomicose/patologia , Animais , Animais Recém-Nascidos , Doenças das Aves/patologia , Granuloma/diagnóstico , Granuloma/patologia , Imuno-Histoquímica/veterinária , Nocardia/isolamento & purificação , Nocardiose/diagnóstico , Nocardiose/patologia
16.
Curr Biol ; 16(20): 2035-41, 2006 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-17055983

RESUMO

In the early Drosophila embryo, asymmetric distribution of transcription factors, established as a consequence of translational control of their maternally derived mRNAs, initiates pattern formation . For instance, translation of the uniformly distributed maternal hunchback (hb) mRNA is inhibited at the posterior to form an anterior-to-posterior protein concentration gradient along the longitudinal axis . Inhibition of hb mRNA translation requires an mRNP complex (the NRE complex), which consists of Nanos (Nos), Pumilio (Pum), and Brain tumor (Brat) proteins, and the Nos responsive element (NRE) present in the 3' UTR of hb mRNA . The identity of the mRNA 5' effector protein that is responsible for this translational inhibition remained elusive. Here we show that d4EHP, a cap binding protein that represses caudal (cad) mRNA translation , also inhibits hb mRNA translation by interacting simultaneously with the mRNA 5' cap structure (m(7)GpppN, where N is any nucleotide) and Brat. Thus, by regulating Cad and Hb expression, d4EHP plays a key role in establishing anterior-posterior axis polarity in the Drosophila embryo.


Assuntos
Padronização Corporal/fisiologia , Proteínas de Drosophila/metabolismo , Drosophila/embriologia , Fator de Iniciação 4E em Eucariotos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , RNA Mensageiro Estocado/metabolismo , Animais , Western Blotting , Clonagem Molecular , Proteínas de Ligação a DNA/imunologia , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/imunologia , Embrião não Mamífero/fisiologia , Fator de Iniciação 4E em Eucariotos/genética , Imunofluorescência , Proteínas de Homeodomínio/metabolismo , Plasmídeos/genética , Fatores de Transcrição/metabolismo
17.
Structure ; 14(5): 913-23, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16698552

RESUMO

The X-ray structure of the C-terminal region of human eukaryotic translation initiation factor 4G (eIF4G) has been determined at 2.2 A resolution, revealing two atypical HEAT-repeat domains. eIF4G recruits various translation factors and the 40S ribosomal subunit to the mRNA 5' end. In higher eukaryotes, the C terminus of eIF4G (4G/C) supports translational regulation by recruiting eIF4A, an RNA helicase, and Mnk1, the kinase responsible for phosphorylating eIF4E. Structure-guided surface mutagenesis and protein-protein interaction assays were used to identify binding sites for eIF4A and Mnk1 within the HEAT-repeats of 4G/C. p97/DAP5, a translational modulator homologous to eIF4G, lacks an eIF4A binding site in the corresponding region. The second atypical HEAT domain of the 4G/C binds Mnk1 using two conserved aromatic/acidic-box (AA-box) motifs. Within the first AA-box, the aromatic residues contribute to the hydrophobic core of the domain, while the acidic residues form a negatively charged surface feature suitable for electrostatic interactions with basic residues in Mnk1.


Assuntos
Fator de Iniciação 4A em Eucariotos/química , Fator de Iniciação Eucariótico 4G/química , Peptídeos e Proteínas de Sinalização Intracelular/química , Proteínas Serina-Treonina Quinases/química , Sequência de Aminoácidos , Aminoácidos Aromáticos/química , Aminoácidos Aromáticos/genética , Sequência Conservada , Cristalografia por Raios X , Fator de Iniciação Eucariótico 4G/genética , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Mutagênese , Mapeamento de Interação de Proteínas , Estrutura Terciária de Proteína
18.
Aust Vet J ; 83(9): 547-9, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16164142

RESUMO

A wild Peregrine Falcon (Falco peregrinus) was presented with extensive bilateral fluorescein positive corneal damage. Local therapy and bilateral tarsorrhaphies resulted in slow improvement over 5 weeks. When bilateral 360 degree conjunctival flaps were used subsequently, healing proceeded more rapidly over the next 8 weeks. Although bulbar conjunctival flaps have been reported as difficult in birds due to their small size and relatively immobile bulbar conjunctiva, 360 degree conjunctival flaps made from palpebral rather than bulbar conjunctiva were found to be technically feasible in a larger bird species such as the Peregrine Falcon.


Assuntos
Doenças das Aves/cirurgia , Úlcera da Córnea/veterinária , Falconiformes , Ceratite/veterinária , Procedimentos Cirúrgicos Oftalmológicos/veterinária , Animais , Animais Selvagens , Doenças das Aves/tratamento farmacológico , Terapia Combinada/veterinária , Túnica Conjuntiva/cirurgia , Úlcera da Córnea/tratamento farmacológico , Úlcera da Córnea/cirurgia , Feminino , Ceratite/tratamento farmacológico , Ceratite/cirurgia , Procedimentos Cirúrgicos Oftalmológicos/métodos , Retalhos Cirúrgicos/veterinária , Resultado do Tratamento
19.
Proteins ; 60(4): 787-96, 2005 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16021622

RESUMO

The targets of the Structural GenomiX (SGX) bacterial genomics project were proteins conserved in multiple prokaryotic organisms with no obvious sequence homolog in the Protein Data Bank of known structures. The outcome of this work was 80 structures, covering 60 unique sequences and 49 different genes. Experimental phase determination from proteins incorporating Se-Met was carried out for 45 structures with most of the remainder solved by molecular replacement using members of the experimentally phased set as search models. An automated tool was developed to deposit these structures in the Protein Data Bank, along with the associated X-ray diffraction data (including refined experimental phases) and experimentally confirmed sequences. BLAST comparisons of the SGX structures with structures that had appeared in the Protein Data Bank over the intervening 3.5 years since the SGX target list had been compiled identified homologs for 49 of the 60 unique sequences represented by the SGX structures. This result indicates that, for bacterial structures that are relatively easy to express, purify, and crystallize, the structural coverage of gene space is proceeding rapidly. More distant sequence-structure relationships between the SGX and PDB structures were investigated using PDB-BLAST and Combinatorial Extension (CE). Only one structure, SufD, has a truly unique topology compared to all folds in the PDB.


Assuntos
Proteínas de Escherichia coli/química , Escherichia coli/genética , Genoma Bacteriano , Genômica , Bases de Dados de Proteínas , Enzimas/química , Enzimas/genética , Proteínas de Escherichia coli/genética , Modelos Moleculares , Conformação Proteica , Análise de Regressão , Difração de Raios X
20.
Cell ; 121(3): 411-23, 2005 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-15882623

RESUMO

Translational control is a key genetic regulatory mechanism implicated in regulation of cell and organismal growth and early embryonic development. Initiation at the mRNA 5' cap structure recognition step is frequently targeted by translational control mechanisms. In the Drosophila embryo, cap-dependent translation of the uniformly distributed caudal (cad) mRNA is inhibited in the anterior by Bicoid (Bcd) to create an asymmetric distribution of Cad protein. Here, we show that d4EHP, an eIF4E-related cap binding protein, specifically interacts with Bcd to suppress cad translation. Translational inhibition depends on the Bcd binding region (BBR) present in the cad 3' untranslated region. Thus, simultaneous interactions of d4EHP with the cap structure and of Bcd with BBR renders cad mRNA translationally inactive. This example of cap-dependent translational control that is not mediated by canonical eIF4E defines a new paradigm for translational inhibition involving tethering of the mRNA 5' and 3' ends.


Assuntos
Proteínas de Drosophila/fisiologia , Fator de Iniciação 4E em Eucariotos/genética , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/metabolismo , Biossíntese de Proteínas/genética , RNA Mensageiro/metabolismo , Transativadores/metabolismo , Regiões 3' não Traduzidas/genética , Sequência de Aminoácidos , Animais , Sítios de Ligação/genética , Padronização Corporal/genética , Linhagem Celular , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/embriologia , Drosophila melanogaster/genética , Drosophila melanogaster/fisiologia , Embrião não Mamífero/embriologia , Embrião não Mamífero/metabolismo , Fator de Iniciação 4E em Eucariotos/metabolismo , Fator de Iniciação 4E em Eucariotos/fisiologia , Proteínas de Homeodomínio/genética , Humanos , Modelos Biológicos , Dados de Sequência Molecular , Mutação , Ligação Proteica/genética , Proteínas de Ligação ao Cap de RNA/genética , Proteínas de Ligação ao Cap de RNA/metabolismo , Capuzes de RNA/metabolismo , Homologia de Sequência de Aminoácidos , Transativadores/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
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