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1.
Genes Dev ; 33(19-20): 1355-1360, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31439631

RESUMO

GIGYF (Grb10-interacting GYF [glycine-tyrosine-phenylalanine domain]) proteins coordinate with 4EHP (eIF4E [eukaryotic initiation factor 4E] homologous protein), the DEAD (Asp-Glu-Ala-Asp)-box helicase Me31B/DDX6, and mRNA-binding proteins to elicit transcript-specific repression. However, the underlying molecular mechanism remains unclear. Here, we report that GIGYF contains a motif necessary and sufficient for direct interaction with Me31B/DDX6. A 2.4 Å crystal structure of the GIGYF-Me31B complex reveals that this motif arranges into a coil connected to a ß hairpin on binding to conserved hydrophobic patches on the Me31B RecA2 domain. Structure-guided mutants indicate that 4EHP-GIGYF-DDX6 complex assembly is required for tristetraprolin-mediated down-regulation of an AU-rich mRNA, thus revealing the molecular principles of translational repression.


Assuntos
Proteínas de Transporte/química , RNA Helicases DEAD-box/química , Fator de Iniciação 4E em Eucariotos/metabolismo , Regulação da Expressão Gênica/genética , Modelos Moleculares , Motivos de Aminoácidos , Animais , Proteínas de Transporte/genética , Linhagem Celular , Drosophila melanogaster/genética , Células HEK293 , Humanos , Ligação Proteica , Estrutura Quaternária de Proteína
2.
Genes Dev ; 31(11): 1147-1161, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28698298

RESUMO

The eIF4E homologous protein (4EHP) is thought to repress translation by competing with eIF4E for binding to the 5' cap structure of specific mRNAs to which it is recruited through interactions with various proteins, including the GRB10-interacting GYF (glycine-tyrosine-phenylalanine domain) proteins 1 and 2 (GIGYF1/2). Despite its similarity to eIF4E, 4EHP does not interact with eIF4G and therefore fails to initiate translation. In contrast to eIF4G, GIGYF1/2 bind selectively to 4EHP but not eIF4E. Here, we present crystal structures of the 4EHP-binding regions of GIGYF1 and GIGYF2 in complex with 4EHP, which reveal the molecular basis for the selectivity of the GIGYF1/2 proteins for 4EHP. Complementation assays in a GIGYF1/2-null cell line using structure-based mutants indicate that 4EHP requires interactions with GIGYF1/2 to down-regulate target mRNA expression. Our studies provide structural insights into the assembly of 4EHP-GIGYF1/2 repressor complexes and reveal that rather than merely facilitating 4EHP recruitment to transcripts, GIGYF1/2 proteins are required for repressive activity.


Assuntos
Proteínas de Transporte/química , Proteínas de Transporte/metabolismo , Regulação da Expressão Gênica/genética , Proteínas de Ligação ao Cap de RNA/metabolismo , RNA Mensageiro/genética , Proteínas de Transporte/genética , Linhagem Celular , Cristalização , Fator de Iniciação 4E em Eucariotos , Células HEK293 , Humanos , Modelos Moleculares , Mutação , Ligação Proteica/genética , Estabilidade Proteica , Estrutura Quaternária de Proteína , Proteínas de Ligação ao Cap de RNA/química
3.
Mol Cell ; 64(3): 467-479, 2016 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-27773676

RESUMO

Eukaryotic initiation factor 4G (eIF4G) plays a central role in translation initiation through its interactions with the cap-binding protein eIF4E. This interaction is a major drug target for repressing translation and is naturally regulated by 4E-binding proteins (4E-BPs). 4E-BPs and eIF4G compete for binding to the eIF4E dorsal surface via a shared canonical 4E-binding motif, but also contain auxiliary eIF4E-binding sequences, which were assumed to contact non-overlapping eIF4E surfaces. However, it is unknown how metazoan eIF4G auxiliary sequences bind eIF4E. Here, we describe crystal structures of human and Drosophila melanogaster eIF4E-eIF4G complexes, which unexpectedly reveal that the eIF4G auxiliary sequences bind to the lateral surface of eIF4E, using a similar mode to that of 4E-BPs. Our studies provide a molecular model of the eIF4E-eIF4G complex, shed light on the competition mechanism of 4E-BPs, and enable the rational design of selective eIF4G inhibitors to dampen dysregulated translation in disease.


Assuntos
Drosophila melanogaster/metabolismo , Fator de Iniciação 4E em Eucariotos/química , Fator de Iniciação Eucariótico 4G/química , Iniciação Traducional da Cadeia Peptídica , Sequência de Aminoácidos , Animais , Sítios de Ligação , Clonagem Molecular , Cristalografia por Raios X , Drosophila melanogaster/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Fator de Iniciação 4E em Eucariotos/genética , Fator de Iniciação 4E em Eucariotos/metabolismo , Fator de Iniciação Eucariótico 4G/genética , Fator de Iniciação Eucariótico 4G/metabolismo , Expressão Gênica , Humanos , Cinética , Modelos Moleculares , Mutação , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Termodinâmica
4.
Mol Cell ; 57(6): 1074-1087, 2015 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-25702871

RESUMO

The eIF4E-binding proteins (4E-BPs) represent a diverse class of translation inhibitors that are often deregulated in cancer cells. 4E-BPs inhibit translation by competing with eIF4G for binding to eIF4E through an interface that consists of canonical and non-canonical eIF4E-binding motifs connected by a linker. The lack of high-resolution structures including the linkers, which contain phosphorylation sites, limits our understanding of how phosphorylation inhibits complex formation. Furthermore, the binding mechanism of the non-canonical motifs is poorly understood. Here, we present structures of human eIF4E bound to 4E-BP1 and fly eIF4E bound to Thor, 4E-T, and eIF4G. These structures reveal architectural elements that are unique to 4E-BPs and provide insight into the consequences of phosphorylation. Guided by these structures, we designed and crystallized a 4E-BP mimic that shows increased repressive activity. Our studies pave the way for the rational design of 4E-BP mimics as therapeutic tools to decrease translation during oncogenic transformation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas de Drosophila/química , Fator de Iniciação 4E em Eucariotos/química , Fator de Iniciação 4E em Eucariotos/metabolismo , Fator de Iniciação Eucariótico 4G/química , Peptídeos e Proteínas de Sinalização Intracelular/química , Fatores de Iniciação de Peptídeos/química , Fosfoproteínas/química , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Motivos de Aminoácidos , Animais , Sítios de Ligação , Ligação Competitiva , Proteínas de Transporte/química , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular , Cristalografia por Raios X , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Fator de Iniciação Eucariótico 4G/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Modelos Moleculares , Mimetismo Molecular , Fatores de Iniciação de Peptídeos/genética , Fatores de Iniciação de Peptídeos/metabolismo , Fosfoproteínas/metabolismo , Fosforilação , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
5.
Genes Dev ; 29(17): 1835-49, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26294658

RESUMO

The eIF4E-binding proteins (4E-BPs) are a diverse class of translation regulators that share a canonical eIF4E-binding motif (4E-BM) with eIF4G. Consequently, they compete with eIF4G for binding to eIF4E, thereby inhibiting translation initiation. Mextli (Mxt) is an unusual 4E-BP that promotes translation by also interacting with eIF3. Here we present the crystal structures of the eIF4E-binding regions of the Drosophila melanogaster (Dm) and Caenorhabditis elegans (Ce) Mxt proteins in complex with eIF4E in the cap-bound and cap-free states. The structures reveal unexpected evolutionary plasticity in the eIF4E-binding mode, with a classical bipartite interface for Ce Mxt and a novel tripartite interface for Dm Mxt. Both interfaces comprise a canonical helix and a noncanonical helix that engage the dorsal and lateral surfaces of eIF4E, respectively. Remarkably, Dm Mxt contains a C-terminal auxiliary helix that lies anti-parallel to the canonical helix on the eIF4E dorsal surface. In contrast to the eIF4G and Ce Mxt complexes, the Dm eIF4E-Mxt complexes are resistant to competition by bipartite 4E-BPs, suggesting that Dm Mxt can bind eIF4E when eIF4G binding is inhibited. Our results uncovered unexpected diversity in the binding modes of 4E-BPs, resulting in eIF4E complexes that display differential sensitivity to 4E-BP regulation.


Assuntos
Proteínas de Caenorhabditis elegans/química , Proteínas de Drosophila/química , Regulação da Expressão Gênica/fisiologia , Modelos Moleculares , Domínios e Motivos de Interação entre Proteínas/fisiologia , Animais , Caenorhabditis elegans/química , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Transporte/química , Proteínas de Transporte/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/química , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Evolução Molecular , Variação Genética , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas/genética , Estrutura Terciária de Proteína , Reprodutibilidade dos Testes
6.
J Indian Assoc Pediatr Surg ; 28(1): 41-47, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36910283

RESUMO

Aim: To study the clinicopathological, imaging, and GeneXpert profiles of surgical referrals with abdominal tuberculosis (TB) and to compare the utility of GeneXpert versus conventional diagnostic armamentarium. Materials and Methods: This cohort study which was conducted over a study period of 8 years (2011-18) included seventy-seven children operated with a provisional diagnosis of abdominal TB and those who had either histological (n = 58; 75.3%) or GeneXpert (n = 9) confirmation or had miliary tubercles on exploration with supportive clinical and imaging findings (n = 17; 22.1%). GeneXpert testing was added to the diagnostic armamentarium only in the latter half of the study (2016-18, n = 31). Demographic details, symptomatology, prior antitubercular treatment, GeneXpert positivity, imaging, operative, and histological findings were recorded and analyzed using mean, standard deviation, and range for continuous variables and proportion for categorical variables. Results: Perforation peritonitis (n = 26; 33.8%) and unrelieved obstruction (n = 51; 66.2%) were the main surgical indications. The mean age at presentation was 9.5 ± 3.6 years with a distinct female preponderance. The presence of right lower abdomen lump (n = 23; 29.9%), alternate diarrhea and constipation (n = 34; 44.1%), tubercular toxemia (n = 38; 49.4%), positive history of contact (n = 20; 25.9%), tuberculin positivity (n = 38; 49.4%), fibrocavitary pulmonary lesion (5.2%), clumped bowel loops with pulled-up cecum (n = 23; 29.9%), septated ascites (n = 17), mesenteric lymphadenopathy and omental thickening (n:18; 23.4% each) were the supportive tell-tale signs of the disease. The hallmark of pathological diagnosis was caseous necrosis with epithelioid granulomas (n = 43; 55.8%), nongranulomatous caseation (n = 15; 19.5%), and acid-fast bacilli positivity in 27.3% of patients. GeneXpert was positive in only nine patients with an overall sensitivity of 29% as compared to 75.3% for histopathology. Conclusion: Bacteriological and histological confirmation of the disease eluded us in a significant proportion of patients, requiring a very high index of clinical suspicion to clinch the diagnosis. The current version of GeneXpert has low sensitivity in diagnosing pediatric abdominal TB.

7.
J Oral Maxillofac Surg ; 80(3): 422-430, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34627744

RESUMO

PURPOSE: The purpose of this study was 1) to compare condyle - fossa relationships in the temporomandibular joint (TMJ), and 2) to score condylar resorption by using a TMJ indexing system in patients with JIA and without JIA. METHODS: The present retrospective cross-sectional study included cone-beam computed tomography (CBCT) images obtained from the sagittal, coronal, and axial slices. In the multidisciplinary Pediatric Rheumatology Outpatient Clinic at The University of Alabama at Birmingham (UAB) children with JIA are also examined by a group of orthodontists working in the same institute from October 2018 to July 2019. The predictor variable consists of patients with JIA and without JIA. The primary outcome variables are the depth of the mandibular fossa, joint spaces, axial angles, medio-lateral width, and condyle resorption. Other study variables were age and sex. In this study, the measurements obtained from 2 different groups (with JIA and without JIA) are compared using a t-test, where Tukey is utilized to adjust for multiple comparisons. The left and right joints are analyzed separately as the paired t test conducted showed a significant difference between the 2 joints (P < .05). RESULTS: The study was comprised of 34 patients diagnosed with JIA and 34 healthy subjects. The depth of the mandibular fossa, the anterior joint spaces, the axial angles, and the resorption index showed statistically significant differences between the JIA and healthy groups in both left and right sides (P < .05). However, there was no statistically significant difference in the posterior joint spaces and mediolateral width between JIA and healthy groups in both sides (P > .05). CONCLUSIONS: The results of our study presented the destructive potential of juvenile idiopathic arthritis by using CBCT. CBCT scanning is a helpful tool in the evaluation of the radiographic result of TMJ.


Assuntos
Artrite Juvenil , Artrite Juvenil/complicações , Artrite Juvenil/diagnóstico por imagem , Osso e Ossos , Criança , Tomografia Computadorizada de Feixe Cônico , Estudos Transversais , Humanos , Côndilo Mandibular/diagnóstico por imagem , Estudos Retrospectivos , Articulação Temporomandibular/diagnóstico por imagem
8.
Nucleic Acids Res ; 47(13): 7035-7048, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31114929

RESUMO

The eIF4E-homologous protein (4EHP) is a translational repressor that competes with eIF4E for binding to the 5'-cap structure of specific mRNAs, to which it is recruited by protein factors such as the GRB10-interacting GYF (glycine-tyrosine-phenylalanine domain) proteins (GIGYF). Several experimental evidences suggest that GIGYF proteins are not merely facilitating 4EHP recruitment to transcripts but are actually required for the repressor activity of the complex. However, the underlying molecular mechanism is unknown. Here, we investigated the role of the uncharacterized Drosophila melanogaster (Dm) GIGYF protein in post-transcriptional mRNA regulation. We show that, when in complex with 4EHP, Dm GIGYF not only elicits translational repression but also promotes target mRNA decay via the recruitment of additional effector proteins. We identified the RNA helicase Me31B/DDX6, the decapping activator HPat and the CCR4-NOT deadenylase complex as binding partners of GIGYF proteins. Recruitment of Me31B and HPat via discrete binding motifs conserved among metazoan GIGYF proteins is required for downregulation of mRNA expression by the 4EHP-GIGYF complex. Our findings are consistent with a model in which GIGYF proteins additionally recruit decapping and deadenylation complexes to 4EHP-containing RNPs to induce translational repression and degradation of mRNA targets.


Assuntos
Proteínas de Drosophila/fisiologia , Drosophila melanogaster/genética , Fator de Iniciação 4E em Eucariotos/fisiologia , Regulação da Expressão Gênica , Proteínas de Ligação ao Cap de RNA/fisiologia , RNA Mensageiro/genética , Proteínas Repressoras/fisiologia , Sequência de Aminoácidos , Animais , Sequência Conservada , RNA Helicases DEAD-box/fisiologia , Regulação para Baixo , Endopeptidases/fisiologia , Genes Reporter , Complexos Multiproteicos , Biossíntese de Proteínas , Capuzes de RNA/genética , Capuzes de RNA/metabolismo , Estabilidade de RNA/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/fisiologia , Ribonucleases/fisiologia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
9.
J Insect Sci ; 21(6)2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34723329

RESUMO

One of the most serious bacterial pathogens of Western honey bees (Apis mellifera Linnaeus [Hymenoptera: Apidae]) is Melissococcus plutonius, the cause of the disease European foulbrood. Because European foulbrood is highly variable, with diverse outcomes at both the individual and colony levels, it is difficult to diagnose through visual inspection alone. Common lab diagnostic techniques include microscopic examination and molecular detection through PCR. In 2009, a lateral flow device was developed and validated for field diagnosis of European foulbrood. At the time, M. plutonius was thought to be genetically homogenous, but we have subsequently learned that this bacterium exists as multiple strains, including some strains that are classified as 'atypical' for which the lateral flow device is potentially less effective. These devices are increasingly used in the United States, though they have never been validated using strains from North America. It is essential to validate this device in multiple locations as different strains of M. plutonius circulate in different geographical regions. In this study, we validate the field use of the lateral flow device compared to microscopic examination and qPCR on larval samples from 78 commercial honey bee colonies in the United States with visual signs of infection. In this study, microscopic diagnosis was more sensitive than the lateral flow device (sensitivity = 97.40% and 89.47%, respectively), and we found no false positive results with the lateral flow device. We find high concurrence between the three diagnostic techniques, and all three methods are highly sensitive for diagnosing European foulbrood.


Assuntos
Infecções Bacterianas/veterinária , Abelhas/microbiologia , Enterococcaceae , Animais , Infecções Bacterianas/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real , Estados Unidos
10.
Artigo em Inglês | MEDLINE | ID: mdl-33219045

RESUMO

INTRODUCTION: Recent years have seen an almost sevenfold rise in referrals to specialist memory clinics. This has been associated with an increased proportion of patients referred with functional cognitive disorder (FCD), that is, non-progressive cognitive complaints. These patients are likely to benefit from a range of interventions (eg, psychotherapy) distinct from the requirements of patients with neurodegenerative cognitive disorders. We have developed a fully automated system, 'CognoSpeak', which enables risk stratification at the primary-secondary care interface and ongoing monitoring of patients with memory concerns. METHODS: We recruited 15 participants to each of four groups: Alzheimer's disease (AD), mild cognitive impairment (MCI), FCD and healthy controls. Participants responded to 12 questions posed by a computer-presented talking head. Automatic analysis of the audio and speech data involved speaker segmentation, automatic speech recognition and machine learning classification. RESULTS: CognoSpeak could distinguish between participants in the AD or MCI groups and those in the FCD or healthy control groups with a sensitivity of 86.7%. Patients with MCI were identified with a sensitivity of 80%. DISCUSSION: Our fully automated system achieved levels of accuracy comparable to currently available, manually administered assessments. Greater accuracy should be achievable through further system training with a greater number of users, the inclusion of verbal fluency tasks and repeat assessments. The current data supports CognoSpeak's promise as a screening and monitoring tool for patients with MCI. Pending confirmation of these findings, it may allow clinicians to offer patients at low risk of dementia earlier reassurance and relieve pressures on specialist memory services.

11.
Sleep Breath ; 24(2): 499-504, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31286329

RESUMO

BACKGROUND: Continuous positive airway pressure (CPAP) is considered the gold standard treatment of obstructive sleep apnea (OSA). However, it can be a challenge in some patients to find an effective CPAP setting that is well tolerated. A lower CPAP setting may improve patient tolerance of the treatment. The objective of this study was to evaluate the effect of approximately 30° torso elevation on minimum effective CPAP for the treatment of OSA. METHODS: A retrospective chart review was performed to determine the effective CPAP setting required to treat OSA in patients who underwent CPAP titration with torso elevation using a wedge cushion, after having failed during the same titration study to achieve therapeutic results at CPAP of 20 cm H2O without torso elevation. RESULTS: Thirty-nine patients who underwent CPAP titration with and without torso elevation utilizing a wedge cushion had statistically significant lowering of the minimum effective CPAP setting with torso elevation, with a mean CPAP reduction of 4.7 (p < 0.001) compared to ineffective treatment at CPAP of 20 cm H2O without torso elevation. Apnea hypopnea index (AHI), respiratory disturbance index (RDI), and lowest oxygen saturation (SpO2) were all improved with torso elevation, with a mean AHI difference of 4.4 (p = 0.03), mean RDI difference of 14.2 (p = 0.001), and mean SpO2 difference of 5.9% (p = 0.002). Age and BMI were inversely correlated, and gender had no correlation with therapeutic CPAP settings with use of torso elevation. CONCLUSION: Torso elevation of approximately 30° resulted in effective CPAP treatment at settings significantly lower than 20 cm H2O in all reviewed OSA patients, who had been ineffectively treated without torso elevation at the maximum tested setting of 20 cm H2O. This intervention may be a useful adjunct during in-lab titration studies for patients who are not effectively treated at or cannot tolerate high CPAP settings.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas , Postura/fisiologia , Apneia Obstrutiva do Sono/terapia , Tronco , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Apneia Obstrutiva do Sono/fisiopatologia , Resultado do Tratamento
12.
Nucleic Acids Res ; 46(13): 6893-6908, 2018 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-30053226

RESUMO

The interaction of the eukaryotic initiation factor 4G (eIF4G) with the cap-binding protein eIF4E initiates cap-dependent translation and is regulated by the 4E-binding proteins (4E-BPs), which compete with eIF4G to repress translation. Metazoan eIF4G and 4E-BPs interact with eIF4E via canonical and non-canonical motifs that bind to the dorsal and lateral surface of eIF4E in a bipartite recognition mode. However, previous studies pointed to mechanistic differences in how fungi and metazoans regulate protein synthesis. We present crystal structures of the yeast eIF4E bound to two yeast 4E-BPs, p20 and Eap1p, as well as crystal structures of a fungal eIF4E-eIF4G complex. We demonstrate that the core principles of molecular recognition of eIF4E are in fact highly conserved among translational activators and repressors in eukaryotes. Finally, we reveal that highly specialized structural motifs do exist and serve to modulate the affinity of protein-protein interactions that regulate cap-dependent translation initiation in fungi.


Assuntos
Fator de Iniciação 4E em Eucariotos/química , Fator de Iniciação Eucariótico 4G/química , Regulação Fúngica da Expressão Gênica , Iniciação Traducional da Cadeia Peptídica , Proteínas de Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/genética , Fatores de Transcrição/química , Motivos de Aminoácidos , Ligação Competitiva , Chaetomium/genética , Sequência Conservada , Cristalografia por Raios X , Fator de Iniciação 4E em Eucariotos/metabolismo , Fator de Iniciação Eucariótico 4G/metabolismo , Evolução Molecular , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Análogos de Capuz de RNA/metabolismo , Proteínas Recombinantes/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Espalhamento a Baixo Ângulo , Alinhamento de Sequência , Especificidade da Espécie , Relação Estrutura-Atividade , Fatores de Transcrição/metabolismo
13.
J Med Internet Res ; 22(5): e16157, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32436852

RESUMO

BACKGROUND: Electronic health (eHealth) is a rapidly evolving field informed by multiple scientific disciplines. Because of this, the use of different terms and concepts to explain the same phenomena and lack of standardization in reporting interventions often leaves a gap that hinders knowledge accumulation. Interventions focused on self-management support of cardiovascular diseases through the use of remote monitoring technologies are a cross-disciplinary area potentially affected by this gap. A review of the underlying frameworks, models, and theories that have informed projects at this crossroad could advance future research and development efforts. OBJECTIVE: This research aimed to identify and compare underlying approaches that have informed interventions focused on self-management support of cardiovascular diseases through the use of remote monitoring technologies. The objective was to achieve an understanding of the distinct approaches by highlighting common or conflicting principles, guidelines, and methods. METHODS: The metaethnography approach was used to review and synthesize researchers' reports on how they applied frameworks, models, and theories in their projects. Literature was systematically searched in 7 databases: Scopus, Web of Science, EMBASE, CINAHL, PsycINFO, Association for Computing Machinery Digital Library, and Cochrane Library. Included studies were thoroughly read and coded to extract data for the synthesis. Studies were mainly related by the key ingredients of the underlying approaches they applied. The key ingredients were finally translated across studies and synthesized into thematic clusters. RESULTS: Of 1224 initial results, 17 articles were included. The articles described research and development of 10 different projects. Frameworks, models, and theories (n=43) applied by the projects were identified. Key ingredients (n=293) of the included articles were mapped to the following themes of eHealth development: (1) it is a participatory process; (2) it creates new infrastructures for improving health care, health, and well-being; (3) it is intertwined with implementation; (4) it integrates theory, evidence, and participatory approaches for persuasive design; (5) it requires continuous evaluation cycles; (6) it targets behavior change; (7) it targets technology adoption; and (8) it targets health-related outcomes. CONCLUSIONS: The findings of this review support and exemplify the numerous possibilities in the use of frameworks, models, and theories to guide research and development of eHealth. Participatory, user-centered design, and integration with empirical evidence and theoretical modeling were widely identified principles in the literature. On the contrary, less attention has been given to the integration of implementation in the development process and supporting novel eHealth-based health care infrastructures. To better integrate theory and evidence, holistic approaches can combine patient-centered studies with consolidated knowledge from expert-based approaches. TRIAL REGISTRATION: PROSPERO CRD42018104397; https://tinyurl.com/y8ajyajt. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.2196/13334.


Assuntos
Doenças Cardiovasculares/terapia , Consulta Remota/métodos , Autogestão/métodos , Telemedicina/métodos , Humanos
14.
Hepatology ; 66(6): 1779-1793, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28665004

RESUMO

Hepatitis B virus (HBV) infects hepatocytes specifically and causes immune-mediated liver damage. How HBV interacts with the innate immunity at the early phase of infection, either with hepatocytes or other cells in the liver, remains controversial. To address this question, we utilized various human cell-culture models and humanized Alb-uPA/SCID mice. All these models were unable to mount an interferon (IFN) response despite robust HBV replication. To elucidate the mechanisms involved in the lack of IFN response, we examined whether HBV actively inhibits innate immune functions of hepatocytes. By treating HBV-infected cells with known inducers of the IFN signaling pathway, we observed no alteration of either sensing or downstream IFN response by HBV. We showed that the DNA innate sensing pathways are poorly active in hepatocytes, consistent with muted innate immune recognition of HBV. Upon exposure to high-level HBV, human macrophages could be activated with increased inflammatory cytokine expressions. CONCLUSION: HBV behaves like a "stealth" virus and is not sensed by, nor actively interferes with, the intrinsic innate immunity of infected hepatocytes. Macrophages are capable of sensing HBV, but require exposure to high HBV titers, potentially explaining the long "window period" during acute infection and HBV's propensity to chronic infection. (Hepatology 2017;66:1779-1793).


Assuntos
Vírus da Hepatite B/fisiologia , Hepatócitos/imunologia , Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata , Macrófagos/fisiologia , Citocinas/metabolismo , Células Hep G2 , Hepatite B/imunologia , Humanos , Interferons/metabolismo
15.
J Hepatol ; 66(3): 494-503, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27746336

RESUMO

BACKGROUND & AIMS: One major obstacle of hepatitis B virus (HBV) research is the lack of efficient cell culture system permissive for viral infection and replication. The aim of our study was to establish a robust HBV infection model by using hepatocyte-like cells (HLCs) derived from human pluripotent stem cells. METHODS: HLCs were differentiated from human embryonic stem cells and induced pluripotent stem cells. Maturation of hepatocyte functions was determined. After HBV infection, total viral DNA, cccDNA, total viral RNA, pgRNA, HBeAg and HBsAg were measured. RESULTS: More than 90% of the HLCs expressed strong signals of human hepatocyte markers, like albumin, as well as known host factors required for HBV infection, suggesting that these cells possessed key features of mature hepatocytes. Notably, HLCs expressed the viral receptor sodium-taurocholate cotransporting polypeptide more stably than primary human hepatocytes (PHHs). HLCs supported robust infection and some spreading of HBV. Finally, by using this model, we identified two host-targeting agents, genistin and PA452, as novel antivirals. CONCLUSIONS: Stem cell-derived HLCs fully support HBV infection. This novel HLC HBV infection model offers a unique opportunity to advance our understanding of the molecular details of the HBV life cycle; to further characterize virus-host interactions and to define new targets for HBV curative treatment. LAY SUMMARY: Our study used human pluripotent stem cells to develop hepatocyte-like cells (HLCs) capable of expressing hepatocyte markers and host factors important for HBV infection. These cells fully support HBV infection and virus-host interactions, allowing for the identification of two novel antiviral agents. Thus, stem cell-derived HLCs provide a highly physiologically relevant system to advance our understanding of viral life cycle and provide a new tool for antiviral drug screening and development.


Assuntos
Hepatite B/virologia , Hepatócitos/virologia , Células-Tronco/virologia , Antivirais/farmacologia , Diferenciação Celular , Linhagem Celular , Células Cultivadas , Descoberta de Drogas , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/virologia , Hepatite B/tratamento farmacológico , Hepatite B/patologia , Vírus da Hepatite B/patogenicidade , Vírus da Hepatite B/fisiologia , Hepatócitos/citologia , Interações Hospedeiro-Patógeno , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/virologia , Modelos Biológicos , Células-Tronco/citologia , Replicação Viral
16.
Pulm Pharmacol Ther ; 44: 96-105, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28315490

RESUMO

Smoking is an important risk factor for the development of chronic obstructive pulmonary disease (COPD) and viral infections are believed to be major triggers of exacerbations, which periodically lead to a worsening of symptoms. The pro-inflammatory IL-1 family members IL-1α and IL-1ß are increased in COPD patients and might contribute to disease pathology. We investigated whether individual or combined inhibition of these cytokines reduced lung inflammation in cigarette smoke (CS)-exposed and H1N1-infected BALB/c mice. Animals were treated with individual or combined antibodies (Abs) directed against IL-1α, IL-1ß or IL-1R1. Cells in BAL fluid and cytokines/chemokines in lung homogenate were determined. The viral load was investigated. Blocking IL-1α had significant suppressive effects on total cells, neutrophils, and macrophages. Furthermore, it reduced KC levels significantly. Blocking of IL-1ß did not provide significant activity. In primary human bronchial epithelial air-liquid-interface cell cultures infected with H1N1, IL-1α Abs but not IL-1ß Abs reduced levels of TNF-α and IL-6. Concomitant usage of Abs against IL-1α/IL-1ß revealed strong effects in vivo and reduced total cells, neutrophils and macrophages. Additionally, levels of KC, IL-6, TNF-α, MCP-1, MIP-1α and MIP-1ß were significantly reduced and ICAM-1 and MUC5 A/C mRNA expression was attenuated. The viral load decreased significantly upon combined IL-1α/IL-1ß Ab treatment. Blocking the IL-1R1 provided significant effects on total cells, neutrophils and macrophages but was inferior compared to inhibiting both its soluble ligands IL-1α/IL-1ß. Our results suggest that combined inhibition of IL-1α/IL-1ß might be beneficial to reduce CS/H1N1-induced airway inflammation. Moreover, combined targeting of both IL-1α/IL-1ß might be more efficient compared to individual neutralization IL-1α or IL-1ß or inhibition of the IL-1R1.


Assuntos
Interleucina-1alfa/metabolismo , Interleucina-1beta/metabolismo , Pneumonia/prevenção & controle , Fumar/efeitos adversos , Animais , Anticorpos , Modelos Animais de Doenças , Feminino , Humanos , Inflamação/etiologia , Inflamação/patologia , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/complicações , Interleucina-1alfa/imunologia , Interleucina-1beta/imunologia , Interleucina-6/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Neutrófilos/metabolismo , Infecções por Orthomyxoviridae/complicações , Pneumonia/etiologia , Fatores de Risco , Fumaça/efeitos adversos , Nicotiana , Fator de Necrose Tumoral alfa/metabolismo
17.
Pflege ; 30(2): 65-75, 2017.
Artigo em Alemão | MEDLINE | ID: mdl-28050915

RESUMO

Background: In the guidelines issued by the Robert Koch Institute, the training and establishing of infection control link nurses (HYG-PFLEGs) as multipliers is stipulated in order to propagate the acceptance and implementation of recommended hygiene measures. To date, there is no standardized format for the further education of these nurses in Germany. Aim: To develop a modular curriculum for HYG-PFLEGs to be trained by infection control nurses. Method: Ward managers (n = 15) and infection control nurses (n = 14) from different hospitals in North Rhine-Westphalia were interviewed about the specific requirements for curricula for infection control link nurses. Four focus group interviews were carried out between October 2012 and January 2013. The tape recordings were transcribed and analysed according to Mayring's content analysis. Results: HYG-PFLEGs were regarded as an indispensable entity for controlling the flow of information between the wards and hygiene teams in hospitals. A core curriculum adjustable for differing institutions should contain a high share of hygiene-related contents, pedagogical-didactical, and psychological competencies as well as practical forms of education. Conclusions: Within the context of the implementation of complex interventions these results provide a basis for the development and implementation of a modular curriculum for infection control link nurses.


Assuntos
Infecção Hospitalar/enfermagem , Currículo , Educação em Enfermagem/organização & administração , Higiene/educação , Especialidades de Enfermagem/educação , Competência Clínica , Infecção Hospitalar/prevenção & controle , Grupos Focais , Alemanha , Humanos
18.
Biotechnol Bioeng ; 113(11): 2485-95, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27159557

RESUMO

Islet transplantation is a potential cure for diabetic patients, however this procedure is not widely adopted due to the high rate of graft failure. Islet encapsulation within hydrogels is employed to provide a three-dimensional microenvironment conducive to survival of transplanted islets to extend graft function. Herein, we present a novel macroencapsulation device, composed of PEG hydrogel, that combines encapsulation with lithography techniques to generate polydimethylsiloxane (PDMS) molds. PEG solutions are mixed with islets, which are then cast into PDMS molds for subsequent crosslinking. The molds can also be employed to provide complex architectures, such as microchannels that may allow vascular ingrowth through pre-defined regions of the hydrogel. PDMS molds allowed for the formation of stable gels with encapsulation of islets, and in complex architectures. Hydrogel devices with a thickness of 600 µm containing 500 islets promoted normoglycemia within 12 days following transplantation into the epididymal fat pad, which was sustained over the two-month period of study until removal of the device. The inclusion of microchannels, which had a similar minimum distance between islets and the hydrogel surface, similarly promoted normoglycemia. A glucose challenge test indicated hydrogel devices achieved normoglycemia 90 min post-dextrose injections, similar to control mice with native pancreata. Histochemical staining revealed that transplanted islets, identified as insulin positive, were viable and isolated from host tissue at 8 weeks post-transplantation, yet devices with microchannels had tissue and vascular ingrowth within the channels. Taken together, these results demonstrate a system for creating non-degradable hydrogels with complex geometries for encapsulating islets capable of restoring normoglycemia, which may expand islet transplantation as a treatment option for diabetic patients. Biotechnol. Bioeng. 2016;113: 2485-2495. © 2016 Wiley Periodicals, Inc.


Assuntos
Cápsulas/síntese química , Diabetes Mellitus/patologia , Diabetes Mellitus/terapia , Hidrogéis/química , Transplante das Ilhotas Pancreáticas/instrumentação , Ilhotas Pancreáticas/citologia , Implantes Absorvíveis , Animais , Sobrevivência Celular , Células Cultivadas , Desenho de Equipamento , Análise de Falha de Equipamento , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Resultado do Tratamento
19.
J Med Ethics ; 42(7): 429-34, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26988548

RESUMO

OBJECTIVE: The purpose of this study was to determine the opinions of practising neonatologists regarding the ethical permissibility of unilateral Do Not Attempt Resuscitation (DNAR) decisions in the neonatal intensive care unit. STUDY DESIGN: An anonymous survey regarding the permissibility of unilateral DNAR orders for three clinical vignettes was sent to members of the American Academy of Pediatrics Section of Perinatal Medicine. RESULTS: There were 490 out of a possible 3000 respondents (16%). A majority (76%) responded that a unilateral DNAR decision would be permissible in cases for which survival was felt to be impossible. A minority (25%) responded 'yes' when asked if a unilateral DNAR order would be permissible based solely on neurological prognosis. CONCLUSIONS: A majority of neonatologists believed unilateral DNAR decisions are ethically permissible if survival is felt to be impossible, but not permissible based solely on poor neurological prognosis. This has significant implications for clinical care.


Assuntos
Estado Terminal , Neonatologistas , Padrões de Prática Médica/ética , Ordens quanto à Conduta (Ética Médica) , Atitude do Pessoal de Saúde , Estado Terminal/classificação , Tomada de Decisões , Humanos , Recém-Nascido , Prognóstico , Qualidade de Vida , Ordens quanto à Conduta (Ética Médica)/ética , Estados Unidos
20.
J Craniofac Surg ; 27(6): 1462-4, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27607115

RESUMO

OBJECTIVES: To set forth a universal standard methodology for quantifying volumetric and linear changes in the craniofacial complex, utilizing three-dimensional data captured from a cleft-lip palate patient who underwent rigid external device (RED) distraction. METHODS: Cone beam computed tomography images of a 14-year-old patient were captured using a Kodak 9500 (Atlanta, GA) Cone Beam system device and a stereophotogrammetric system (3dMDface(TM) Atlanta, GA). The subject was a nonsyndromic unilateral cleft-lip palate patient who received RED distraction as part of maxillary advancement in conjunction with orthodontic treatment. Preop (T1) and postop (T2) images were superimposed using Invivo 5.2.3 (San Jose, CA) software. Volumetric rendering of the airway, bone, and soft tissues, as well as linear measurements were analyzed. Each measurement was captured 10 times to ensure reliability and reproducibility of methodology. RESULTS: Data from T1 to T2 revealed mean differences as follows: airway total volume +5250 mm, minimum cross-sectional area +67.84 mm; bone +1719 mm, soft tissue +44,432 mm. Mean of linear measurements: Pronasale 1.98 mm, Subnasale 3.35 mm, Labial superius 10.79 mm, Labial inferius 4.13 mm, Right alare 5.71 mm, Right cheilion 7.83 mm, Left alare 4.97 mm, Left cheilion 5.50 mm, Pogonion 3.01 mm, B-point 2.49 mm, U1-U1 9.77 mm, and L1-L1 0.00 mm. P values are <0.001 for each analysis. CONCLUSIONS: This paper represents a novel and innovative way to look at prepost RED distractions in a three-dimensional format. A universal standard analysis of the craniofacial complex can be implemented using the techniques and method outlined in this study.


Assuntos
Encéfalo/anormalidades , Cefalometria/métodos , Fenda Labial/diagnóstico , Fissura Palatina/diagnóstico , Tomografia Computadorizada de Feixe Cônico/métodos , Imageamento Tridimensional/métodos , Maxila/diagnóstico por imagem , Osteogênese por Distração/métodos , Adolescente , Encéfalo/cirurgia , Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Humanos , Masculino , Reprodutibilidade dos Testes
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