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1.
Sci Rep ; 13(1): 5894, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-37041188

RESUMO

Axon guidance cues direct the growth and steering of neuronal growth cones, thus guiding the axons to their targets during development. Nonetheless, after axons have reached their targets and established functional circuits, many mature neurons continue to express these developmental cues. The role of axon guidance cues in the adult nervous system has not been fully elucidated. Using the expression pattern data available on FlyBase, we found that more than 96% of the guidance genes that are expressed in the Drosophila melanogaster embryo continue to be expressed in adults. We utilized the GeneSwitch and TARGET systems to spatiotemporally knockdown the expression of these guidance genes selectively in the adult neurons, once the development was completed. We performed an RNA interference (RNAi) screen against 44 guidance genes in the adult Drosophila nervous system and identified 14 genes that are required for adult survival and normal motility. Additionally, we show that adult expression of Semaphorins and Plexins in motor neurons is necessary for neuronal survival, indicating that guidance genes have critical functions in the mature nervous system.


Assuntos
Drosophila melanogaster , Semaforinas , Animais , Drosophila melanogaster/metabolismo , Semaforinas/genética , Neurônios Motores/metabolismo , Axônios/metabolismo , Drosophila/metabolismo
2.
Biol Rev Camb Philos Soc ; 97(1): 115-140, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34476892

RESUMO

The naked mole-rat (Heterocephalus glaber) has fascinated zoologists for at least half a century. It has also generated considerable biomedical interest not only because of its extraordinary longevity, but also because of unusual protective features (e.g. its tolerance of variable oxygen availability), which may be pertinent to several human disease states, including ischemia/reperfusion injury and neurodegeneration. A recent article entitled 'Surprisingly long survival of premature conclusions about naked mole-rat biology' described 28 'myths' which, those authors claimed, are a 'perpetuation of beautiful, but falsified, hypotheses' and impede our understanding of this enigmatic mammal. Here, we re-examine each of these 'myths' based on evidence published in the scientific literature. Following Braude et al., we argue that these 'myths' fall into four main categories: (i) 'myths' that would be better described as oversimplifications, some of which persist solely in the popular press; (ii) 'myths' that are based on incomplete understanding, where more evidence is clearly needed; (iii) 'myths' where the accumulation of evidence over the years has led to a revision in interpretation, but where there is no significant disagreement among scientists currently working in the field; (iv) 'myths' where there is a genuine difference in opinion among active researchers, based on alternative interpretations of the available evidence. The term 'myth' is particularly inappropriate when applied to competing, evidence-based hypotheses, which form part of the normal evolution of scientific knowledge. Here, we provide a comprehensive critical review of naked mole-rat biology and attempt to clarify some of these misconceptions.


Assuntos
Longevidade , Ratos-Toupeira , Animais , Biologia
3.
ATS Sch ; 3(4): 598-609, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36726710

RESUMO

Ultrasound-guided peripheral intravenous (IV) placement is often required for patients with difficult IV access and is associated with a reduction in central line placement. Despite the importance, there is no standardized technical approach, and there is limited ability to attain mastery through simulation. We describe our step-by-step approach for teaching ultrasound-guided IV placement at the bedside using short-axis dynamic guidance, with emphasis on advancing the needle and catheter device almost entirely into the vessel before threading the catheter. Our teaching approach allows the opportunity for trainees to maximize the learning potential of a single insertion experience, which includes focused preprocedure hands-on practice, instruction with real-time feedback at the bedside, and a post-procedure debrief with reinforcement of concepts.

4.
PLoS Genet ; 17(9): e1009774, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34492006

RESUMO

Gene variant discovery is becoming routine, but it remains difficult to usefully interpret the functional consequence or disease relevance of most variants. To fill this interpretation gap, experimental assays of variant function are becoming common place. Yet, it remains challenging to make these assays reproducible, scalable to high numbers of variants, and capable of assessing defined gene-disease mechanism for clinical interpretation aligned to the ClinGen Sequence Variant Interpretation (SVI) Working Group guidelines for 'well-established assays'. Drosophila melanogaster offers great potential as an assay platform, but was untested for high numbers of human variants adherent to these guidelines. Here, we wished to test the utility of Drosophila as a platform for scalable well-established assays. We took a genetic interaction approach to test the function of ~100 human PTEN variants in cancer-relevant suppression of PI3K/AKT signaling in cellular growth and proliferation. We validated the assay using biochemically characterized PTEN mutants as well as 23 total known pathogenic and benign PTEN variants, all of which the assay correctly assigned into predicted functional categories. Additionally, function calls for these variants correlated very well with our recent published data from a human cell line. Finally, using these pathogenic and benign variants to calibrate the assay, we could set readout thresholds for clinical interpretation of the pathogenicity of 70 other PTEN variants. Overall, we demonstrate that Drosophila offers a powerful assay platform for clinical variant interpretation, that can be used in conjunction with other well-established assays, to increase confidence in the accurate assessment of variant function and pathogenicity.


Assuntos
Proliferação de Células , Drosophila melanogaster/genética , PTEN Fosfo-Hidrolase/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Humanos , Transdução de Sinais
5.
Radiol Cardiothorac Imaging ; 3(2): e200564, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33969313

RESUMO

Although US of the lungs is increasingly used clinically, diagnostic radiologists are not routinely trained in its use and interpretation. Lung US is a highly sensitive and specific modality that aids in the evaluation of the lungs for many different abnormalities, including pneumonia, pleural effusion, pulmonary edema, and pneumothorax. This review provides an overview of lung US to equip the diagnostic radiologist with knowledge needed to interpret this increasingly used modality. Supplemental material is available for this article. © RSNA, 2021.

6.
Nat Commun ; 11(1): 2073, 2020 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-32350270

RESUMO

Functional variomics provides the foundation for personalized medicine by linking genetic variation to disease expression, outcome and treatment, yet its utility is dependent on appropriate assays to evaluate mutation impact on protein function. To fully assess the effects of 106 missense and nonsense variants of PTEN associated with autism spectrum disorder, somatic cancer and PTEN hamartoma syndrome (PHTS), we take a deep phenotypic profiling approach using 18 assays in 5 model systems spanning diverse cellular environments ranging from molecular function to neuronal morphogenesis and behavior. Variants inducing instability occur across the protein, resulting in partial-to-complete loss-of-function (LoF), which is well correlated across models. However, assays are selectively sensitive to variants located in substrate binding and catalytic domains, which exhibit complete LoF or dominant negativity independent of effects on stability. Our results indicate that full characterization of variant impact requires assays sensitive to instability and a range of protein functions.


Assuntos
Doença/genética , Modelos Genéticos , Mutação de Sentido Incorreto/genética , PTEN Fosfo-Hidrolase/genética , Animais , Comportamento Animal , Caenorhabditis elegans/fisiologia , Células Cultivadas , Dendritos/fisiologia , Drosophila/genética , Drosophila/crescimento & desenvolvimento , Ensaios Enzimáticos , Células HEK293 , Humanos , Neoplasias/genética , Sistema Nervoso/crescimento & desenvolvimento , Fosforilação , Estabilidade Proteica , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células Piramidais/metabolismo , Ratos Sprague-Dawley , Saccharomyces cerevisiae/metabolismo
7.
J Clin Imaging Sci ; 9: 35, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31538033

RESUMO

OBJECTIVE: Pneumonia is the leading cause of pediatric mortality worldwide among children 0-5 years old. Lung ultrasound can be used to diagnose pneumonia in rural areas as it is a portable and relatively economic imaging modality with ~95% sensitivity and specificity for pneumonia in children. Lack of trained sonographers is the current limiting factor to its deployment in rural areas. In this study, we piloted training of a volume sweep imaging (VSI) ultrasound protocol for pneumonia detection in Peru with rural health workers. VSI may be taught to individuals with limited medical/ultrasound experience as it requires minimal anatomical knowledge and technical skill. In VSI, the target organ is imaged with a series of sweeps and arcs of the ultrasound probe in relation to external body landmarks. METHODS: Rural health workers in Peru were trained on a VSI ultrasound protocol for pneumonia detection. Subjects were given a brief didactic session followed by hands-on practice with the protocol. Each attempt was timed and mistakes were recorded. Participants performed the protocol until they demonstrated two mistake-free attempts. RESULTS: It took participants a median number of three attempts (range 1-6) to perform the VSI protocol correctly. Time to mastery took 51.4 ± 17.7 min. There were no significant differences among doctors, nurses, and technicians in total training time (P = 0.43) or number of attempts to success (P = 0.72). Trainee age was not found to be significantly correlated with training time (P = 0.50) or number of attempts to success (P = 0.40). CONCLUSION: Rural health workers learned a VSI protocol for pneumonia detection with relative ease in a short amount of time. Future studies should investigate the clinical efficacy of this VSI protocol for pneumonia detection. KEY MESSAGE: A volume sweep imaging (VSI) protocol for pneumonia detection can be taught with minimal difficulty to rural health workers without prior ultrasound experience. No difference was found in training performance related to education level or age. VSI involves no significant knowledge of anatomy or technical skill.

9.
J Vasc Surg ; 69(2): 507-515, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30683197

RESUMO

OBJECTIVE: Arteriovenous fistulas created in patients with chronic kidney disease often lose patency and fail to become usable. This prospective trial evaluated the efficacy of vonapanitase, a recombinant human elastase, in promoting radiocephalic fistula patency and use for hemodialysis. METHODS: PATENCY-1 was a double-blind, placebo-controlled trial that enrolled 349 patients on or approaching hemodialysis and being evaluated for radiocephalic arteriovenous fistula creation. Of these, 313 were randomized and 311 treated. Patients were assigned to vonapanitase (n = 210) or placebo (n = 103). The study drug solution was applied topically to the artery and vein for 10 minutes immediately after fistula creation. The primary and secondary end points were primary patency (time to first thrombosis or corrective procedure) and secondary patency (time to abandonment). Tertiary end points included use of the fistula for hemodialysis, fistula maturation by ultrasound, and procedure rates. RESULTS: The Kaplan-Meier estimates of 12-month primary patency were 42% (95% confidence interval [CI], 35-49) and 31% (95% CI, 21-42) for vonapanitase and placebo (P = .25). The Kaplan-Meier estimates of 12-month secondary patency were 74% (95% CI, 68-80) and 61% (95% CI, 51-71) for vonapanitase and placebo (P = .048). The proportions of vonapanitase and placebo patients were 39% and 25% (P = .035) with unassisted use for hemodialysis and 64% and 44% (P = .006) with unassisted plus assisted use. CONCLUSIONS: Vonapanitase treatment did not significantly improve primary patency but was associated with increased secondary patency and use for hemodialysis. Further research is needed to evaluate these end points.


Assuntos
Derivação Arteriovenosa Cirúrgica , Proteínas de Transporte/administração & dosagem , Oclusão de Enxerto Vascular/prevenção & controle , Elastase Pancreática/administração & dosagem , Artéria Radial/cirurgia , Diálise Renal , Trombose/prevenção & controle , Extremidade Superior/irrigação sanguínea , Grau de Desobstrução Vascular/efeitos dos fármacos , Veias/cirurgia , Administração Tópica , Adulto , Idoso , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Proteínas de Transporte/efeitos adversos , Método Duplo-Cego , Feminino , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Elastase Pancreática/efeitos adversos , Estudos Prospectivos , Artéria Radial/diagnóstico por imagem , Artéria Radial/fisiopatologia , Trombose/etiologia , Trombose/fisiopatologia , Fatores de Tempo , Resultado do Tratamento , Estados Unidos , Veias/diagnóstico por imagem , Veias/fisiopatologia
11.
J Vasc Surg ; 65(4): 1113-1120, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27986480

RESUMO

OBJECTIVE: This study explored the long-term outcomes of arteriovenous fistulas treated with vonapanitase (recombinant human elastase) at the time of surgical creation. METHODS: This was a randomized, double-blind, placebo-controlled trial of 151 patients undergoing radiocephalic or brachiocephalic arteriovenous fistula creation who were randomized equally to placebo, vonapanitase 10 µg, or vonapanitase 30 µg. The results after 1 year of follow-up were previously reported. The current analysis occurred when the last patient treated was observed for 3 years. For the current analysis, the primary end point was primary patency; the secondary end points included secondary patency, use of the fistula for hemodialysis, and rate of procedures to restore or to maintain patency. RESULTS: There was no significant difference in the risk of primary patency loss with vonapanitase 10 µg or 30 µg vs placebo. When seven initial patency loss events related to cephalic arch and central vein balloon angioplasty were excluded, the risk of patency loss was reduced with vonapanitase overall (hazard ratio [HR], 0.63; P = .049) and 30 µg (HR, 0.51; P = .03). In patients with radiocephalic fistulas (n = 67), the risks of primary and secondary patency loss were reduced with 30 µg (HR, 0.37 [P = .02] and 0.24 [P = .046], respectively). The rate of procedures to restore or to maintain fistula patency was reduced with 30 µg vs placebo (0.23 vs 0.72 procedure days/patient/year; P = .03) and also reduced in patients with radiocephalic fistulas with 30 µg vs placebo (0.17 vs 0.85 procedure days/patient/year; P = .048). CONCLUSIONS: In this study, vonapanitase did not significantly improve primary patency in the primary analysis but did significantly improve primary patency in an analysis that excluded patency loss due to cephalic arch and central vein balloon angioplasty. In patients with radiocephalic fistulas, 30 µg significantly improved primary and secondary patency. Vonapanitase 30 µg decreased the rate of procedures to restore or to maintain patency in the analysis that included all patients and in the subset with radiocephalic fistulas.


Assuntos
Derivação Arteriovenosa Cirúrgica , Artéria Braquial/cirurgia , Proteínas de Transporte/uso terapêutico , Oclusão de Enxerto Vascular/prevenção & controle , Elastase Pancreática/uso terapêutico , Artéria Radial/cirurgia , Diálise Renal , Extremidade Superior/irrigação sanguínea , Grau de Desobstrução Vascular/efeitos dos fármacos , Adulto , Idoso , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Artéria Braquial/diagnóstico por imagem , Artéria Braquial/fisiopatologia , Proteínas de Transporte/efeitos adversos , Método Duplo-Cego , Feminino , Oclusão de Enxerto Vascular/diagnóstico por imagem , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/fisiopatologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Elastase Pancreática/efeitos adversos , Estudos Prospectivos , Artéria Radial/diagnóstico por imagem , Artéria Radial/fisiopatologia , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Estados Unidos
12.
Methods Mol Biol ; 1493: 247-263, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27787856

RESUMO

The semaphorins are a large family of secreted and membrane associated proteins that play numerous key roles in the development and function of the nervous system and other tissues. They have been primarily associated with their function as guidance cues in the developing nervous system. In general, semaphorins have been shown to function as inhibitory guidance cues; however there are also numerous examples where they can function as attractive or permissive cues. Thus it is important to employ a variety of assays to test for semaphorin function. While numerous assays have been established for secreted semaphorins, testing the function of transmembrane semaphorins has been challenging. In this chapter we outline two assays that we have used extensively to test their function. In one assay we examine the effect of a constant source of a transmembrane semaphorin on neurite outgrowth and in a second assay we examine whether neurons will actively avoid growing across islands of cells expressing a transmembrane semaphorin. We have found both assays to be relatively easy to perform and useful to test semaphorin function and signaling.


Assuntos
Semaforinas/fisiologia , Animais , Embrião de Galinha , Técnicas de Cocultura , Meios de Cultura , Células HEK293 , Humanos , Técnicas In Vitro , Transdução de Sinais
13.
J Vasc Surg ; 60(2): 454-461.e1, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24684771

RESUMO

OBJECTIVE: This study explored the safety and efficacy of recombinant type I pancreatic elastase (PRT-201) topically applied once to the external surface of an arteriovenous fistula. METHODS: This was a randomized, double-blind, placebo-controlled trial. Adults with kidney disease undergoing creation of a radiocephalic fistula (RCF) or brachiocephalic fistula were randomized to treatment with placebo (n = 51), PRT-201 at 10 µg (n = 51), or PRT-201 at 30 µg (n = 49). The primary efficacy measure was unassisted primary patency (PP) over 1 year. Secondary efficacy measures were secondary patency (SP), unassisted maturation by ultrasound interrogation, use for hemodialysis, and hemodynamically significant lumen stenosis. RESULTS: Median PP was 224 days for placebo and >365 days for the PRT-201 groups. At 1 year, 45%, 54%, and 53% of placebo, 10-µg, and 30-µg patients retained PP. The risk of PP loss was nonsignificantly reduced for 10 µg (hazard ratio [HR], 0.69; P = .19) and 30 µg (HR, 0.67; P = .17) vs placebo. In the subset (44% of patients) with a RCF, the median PP was 125 days for placebo and >365 days for the PRT-201 groups. At 1 year, 31%, 50%, and 63% of placebo, 10-µg, and 30-µg RCFs retained PP. The risk of RCF PP loss was nonsignificantly reduced by 10 µg (HR, 0.59; P = .18) and significantly reduced by 30 µg (HR, 0.37; P = .02) vs placebo. At 1 year, 77%, 81%, and 83% of placebo, 10-µg, and 30-µg patients retained SP. The risk of SP loss was nonsignificantly reduced for 10 µg (HR, 0.79; P = .61) and 30 µg (HR, 0.76; P = .55) vs placebo. In the subset with RCFs, 65%, 82%, and 90% of placebo, 10-µg, and 30-µg patients retained SP at 1 year. The risk of RCF SP loss was nonsignificantly reduced for 10 µg (HR, 0.45; P = .19) and 30 µg (HR, 0.27; P = .08) vs placebo. At month 3, 67%, 87% (P = .03), and 92% (P < .01) of the placebo, 10-µg, and 30-µg group fistulas had unassisted maturation by ultrasound interrogation. At month 3 in the subset with an RCF, 47%, 74% (P = .17), and 93% (P < .01) of placebo, 10-µg, and 30-µg group fistulas had unassisted maturation by ultrasound interrogation. Adverse event reports were not meaningfully different between groups. CONCLUSIONS: PRT-201 appeared safe. The primary efficacy end point was not met. However, both PRT-201 doses were associated with improved unassisted maturation. The 30-µg dose was associated with increased PP in the subset with RCF.


Assuntos
Derivação Arteriovenosa Cirúrgica , Proteínas de Transporte/administração & dosagem , Oclusão de Enxerto Vascular/prevenção & controle , Diálise Renal , Insuficiência Renal Crônica/terapia , Extremidade Superior/irrigação sanguínea , Administração Cutânea , Adulto , Idoso , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Proteínas de Transporte/efeitos adversos , Constrição Patológica , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Oclusão de Enxerto Vascular/diagnóstico por imagem , Oclusão de Enxerto Vascular/fisiopatologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Elastase Pancreática , Proteínas Recombinantes/administração & dosagem , Insuficiência Renal Crônica/diagnóstico , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia , Estados Unidos , Grau de Desobstrução Vascular/efeitos dos fármacos
14.
Development ; 141(9): 1940-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24718987

RESUMO

During vertebrate development, centrally projecting sensory axons of the dorsal root ganglia neurons first reach the embryonic spinal cord at the dorsolateral margin. Instead of immediately projecting into the grey matter, they bifurcate and extend rostrally and caudally to establish the longitudinal dorsal funiculus during a stereotyped waiting period of approximately 48 h. Collateral fibres then extend concurrently across multiple spinal segments and project to their appropriate targets within the grey matter. This rostrocaudal extension of sensory afferents is crucial for the intersegmental processing of information throughout the spinal cord. However, the precise cues that prevent premature entry during the waiting period remain to be identified. Here, we show that semaphorin 5B (Sema5B), a member of the semaphorin family of guidance molecules, is expressed in the chick spinal cord during this waiting period and dorsal funiculus formation. Sema5B expression is dynamic, with a reduction of expression apparent in the spinal cord concomitant with collateral extension. We show that Sema5B inhibits the growth of NGF-dependent sensory axons and that this effect is mediated in part through the cell adhesion molecule TAG-1. Knockdown of Sema5B in the spinal cord using RNA interference leads to the premature extension of cutaneous nociceptive axons into the dorsal horn grey matter. These premature projections predominantly occur at the site of dorsal root entry. Our results suggest that Sema5B contributes to a repulsive barrier for centrally projecting primary sensory axons, forcing them to turn and establish the dorsal funiculus.


Assuntos
Neurônios Aferentes/metabolismo , Semaforinas/metabolismo , Células Receptoras Sensoriais/metabolismo , Medula Espinal/embriologia , Medula Espinal/metabolismo , Animais , Proteínas Aviárias/antagonistas & inibidores , Proteínas Aviárias/genética , Proteínas Aviárias/metabolismo , Axônios/metabolismo , Padronização Corporal/genética , Embrião de Galinha , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Neurônios Aferentes/citologia , Nociceptividade , Propriocepção/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Semaforinas/genética , Células Receptoras Sensoriais/citologia , Medula Espinal/citologia
15.
J Neurochem ; 123(1): 135-46, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22817385

RESUMO

Developing neuronal growth cones respond to a number of post-transcriptionally modified guidance cues to establish functional neural networks. The Semaphorin family has well-established roles as both secreted and transmembrane guidance cues. Here, we describe the first evidence that a transmembrane Semaphorin, Semaphorin 5B (Sema5B), is proteolytically processed from its transmembrane form and can function as a soluble growth cone collapsing guidance cue. Over-expression of A Disintegrin and Metalloprotease (ADAM)-17, results in an enhanced release of the Sema5B ectodomain, while removal of a predicted ADAM-17 cleavage site prevents its release. In contrast, knockdown of ADAM-17 does not significantly reduce Sema5B release, indicating there are additional unknown compensating proteases. This modulation of the transmembrane Sema5B to a diffusible cue represents a sophisticated method to regulate neuronal guidance in vivo.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Cones de Crescimento/fisiologia , Neurônios/citologia , Semaforinas/metabolismo , Proteínas ADAM/metabolismo , Proteína ADAM17 , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Movimento Celular , Embrião de Galinha , Galinhas , Técnicas de Cocultura , Dimerização , Dipeptídeos/farmacologia , Relação Dose-Resposta a Droga , Gânglios Espinais/citologia , Gânglios Espinais/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/genética , Cones de Crescimento/efeitos dos fármacos , Células HEK293 , Humanos , Inibidores de Metaloproteinases de Matriz/farmacologia , Mutagênese Sítio-Dirigida/métodos , Proteínas do Tecido Nervoso/metabolismo , Neurônios/efeitos dos fármacos , Técnicas de Cultura de Órgãos , Inibidores de Proteases/farmacologia , Semaforinas/genética , Deleção de Sequência/genética , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Inibidor Tecidual de Metaloproteinase-1/farmacologia , Transfecção
16.
PLoS One ; 6(7): e22798, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21829517

RESUMO

BACKGROUND: The first changes associated with smoking are in the small airway epithelium (SAE). Given that smoking alters SAE gene expression, but only a fraction of smokers develop chronic obstructive pulmonary disease (COPD), we hypothesized that assessment of SAE genome-wide gene expression would permit biologic phenotyping of the smoking response, and that a subset of healthy smokers would have a "COPD-like" SAE transcriptome. METHODOLOGY/PRINCIPAL FINDINGS: SAE (10th-12th generation) was obtained via bronchoscopy of healthy nonsmokers, healthy smokers and COPD smokers and microarray analysis was used to identify differentially expressed genes. Individual responsiveness to smoking was quantified with an index representing the % of smoking-responsive genes abnormally expressed (I(SAE)), with healthy smokers grouped into "high" and "low" responders based on the proportion of smoking-responsive genes up- or down-regulated in each smoker. Smokers demonstrated significant variability in SAE transcriptome with I(SAE) ranging from 2.9 to 51.5%. While the SAE transcriptome of "low" responder healthy smokers differed from both "high" responders and smokers with COPD, the transcriptome of the "high" responder healthy smokers was indistinguishable from COPD smokers. CONCLUSION/SIGNIFICANCE: The SAE transcriptome can be used to classify clinically healthy smokers into subgroups with lesser and greater responses to cigarette smoking, even though these subgroups are indistinguishable by clinical criteria. This identifies a group of smokers with a "COPD-like" SAE transcriptome.


Assuntos
Biomarcadores/metabolismo , Epitélio/efeitos dos fármacos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Doença Pulmonar Obstrutiva Crônica/etiologia , Mucosa Respiratória/efeitos dos fármacos , Fumar/efeitos adversos , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Doença Pulmonar Obstrutiva Crônica/patologia
17.
Respir Res ; 10: 111, 2009 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-19919714

RESUMO

BACKGROUND: The small airway epithelium and alveolar macrophages are exposed to oxidants in cigarette smoke leading to epithelial dysfunction and macrophage activation. In this context, we asked: what is the transcriptome of oxidant-related genes in small airway epithelium and alveolar macrophages, and does their response differ substantially to inhaled cigarette smoke? METHODS: Using microarray analysis, with TaqMan RT-PCR confirmation, we assessed oxidant-related gene expression in small airway epithelium and alveolar macrophages from the same healthy nonsmoker and smoker individuals. RESULTS: Of 155 genes surveyed, 87 (56%) were expressed in both cell populations in nonsmokers, with higher expression in alveolar macrophages (43%) compared to airway epithelium (24%). In smokers, there were 15 genes (10%) up-regulated and 7 genes (5%) down-regulated in airway epithelium, but only 3 (2%) up-regulated and 2 (1%) down-regulated in alveolar macrophages. Pathway analysis of airway epithelium showed oxidant pathways dominated, but in alveolar macrophages immune pathways dominated. CONCLUSION: Thus, the response of different cell-types with an identical genome exposed to the same stress of smoking is different; responses of alveolar macrophages are more subdued than those of airway epithelium. These findings are consistent with the observation that, while the small airway epithelium is vulnerable, alveolar macrophages are not "diseased" in response to smoking. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT00224185 and NCT00224198.


Assuntos
Macrófagos Alveolares/metabolismo , Estresse Oxidativo/genética , Mucosa Respiratória/metabolismo , Fumar/genética , Adulto , Lavagem Broncoalveolar , Broncoscopia , Estudos de Casos e Controles , Células Cultivadas , Feminino , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Oxirredução , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fumar/metabolismo
18.
J Cell Sci ; 122(Pt 20): 3810-21, 2009 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-19812310

RESUMO

Neuronal morphology plays an essential role in neuronal function. The establishment and maintenance of neuronal morphology is intimately linked to the actin cytoskeleton; however, the molecular mechanisms that regulate changes in neuronal morphology are poorly understood. Here we identify a novel myosin-Va (MyoVa)-interacting protein, RILPL2, which regulates cellular morphology. Overexpression of this protein in young or mature hippocampal neurons results in an increase in the number of spine-like protrusions. By contrast, knockdown of endogenous RILPL2 in neurons by short hairpin RNA (shRNA) interference results in reduced spine-like protrusions, a phenotype rescued by overexpression of an shRNA-insensitive RILPL2 mutant, suggesting a role for RILPL2 in both the establishment and maintenance of dendritic spines. Interestingly, we demonstrate that RILPL2 and the Rho GTPase Rac1 form a complex, and that RILPL2 is able to induce activation of Rac1 and its target, p21-activated kinase (Pak). Notably, both RILPL2-mediated morphological changes and activation of Rac1-Pak signaling were blocked by expression of a truncated tail form of MyoVa or MyoVa shRNA, demonstrating that MyoVa is crucial for proper RILPL2 function. This might represent a novel mechanism linking RILPL2, the motor protein MyoVa and Rac1 with neuronal structure and function.


Assuntos
Proteínas de Transporte/metabolismo , Forma Celular , Morfogênese , Cadeias Pesadas de Miosina/metabolismo , Miosina Tipo V/metabolismo , Neurônios/citologia , Neurônios/enzimologia , Proteínas rac de Ligação ao GTP/metabolismo , Animais , Axônios/metabolismo , Encéfalo/metabolismo , Células COS , Proteínas de Transporte/química , Chlorocebus aethiops , Espinhas Dendríticas/metabolismo , Ativação Enzimática , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Genes Dominantes , Hipocampo/metabolismo , Camundongos , Especificidade de Órgãos , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Transdução de Sinais , Fatores de Tempo
19.
BMC Genomics ; 10: 493, 2009 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-19852842

RESUMO

BACKGROUND: Microarray technology provides a powerful tool for defining gene expression profiles of airway epithelium that lend insight into the pathogenesis of human airway disorders. The focus of this study was to establish rigorous quality control parameters to ensure that microarray assessment of the airway epithelium is not confounded by experimental artifact. Samples (total n = 223) of trachea, large and small airway epithelium were collected by fiberoptic bronchoscopy of 144 individuals and hybridized to Affymetrix microarrays. The pre- and post-chip quality control (QC) criteria established, included: (1) RNA quality, assessed by RNA Integrity Number (RIN) > or = 7.0; (2) cRNA transcript integrity, assessed by signal intensity ratio of GAPDH 3' to 5' probe sets < or = 3.0; and (3) the multi-chip normalization scaling factor < or = 10.0. RESULTS: Of the 223 samples, all three criteria were assessed in 191; of these 184 (96.3%) passed all three criteria. For the remaining 32 samples, the RIN was not available, and only the other two criteria were used; of these 29 (90.6%) passed these two criteria. Correlation coefficients for pairwise comparisons of expression levels for 100 maintenance genes in which at least one array failed the QC criteria (average Pearson r = 0.90 +/- 0.04) were significantly lower (p < 0.0001) than correlation coefficients for pairwise comparisons between arrays that passed the QC criteria (average Pearson r = 0.97 +/- 0.01). Inter-array variability was significantly decreased (p < 0.0001) among samples passing the QC criteria compared with samples failing the QC criteria. CONCLUSION: Based on the aberrant maintenance gene data generated from samples failing the established QC criteria, we propose that the QC criteria outlined in this study can accurately distinguish high quality from low quality data, and can be used to delete poor quality microarray samples before proceeding to higher-order biological analyses and interpretation.


Assuntos
Perfilação da Expressão Gênica/métodos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Mucosa Respiratória/metabolismo , Adulto , Feminino , Perfilação da Expressão Gênica/normas , Gliceraldeído-3-Fosfato Desidrogenases/genética , Humanos , Pulmão/metabolismo , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos/normas , Controle de Qualidade , RNA/análise , RNA/genética , RNA/metabolismo
20.
J Immunol ; 183(4): 2867-83, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19635926

RESUMO

When exposed to a specific microenvironment, macrophages acquire either M1- or M2-polarized phenotypes associated with inflammation and tissue remodeling, respectively. Alveolar macrophages (AM) directly interact with environmental stimuli such as cigarette smoke, the major risk factor for chronic obstructive pulmonary disease (COPD), a disease characterized by lung inflammation and remodeling. Transcriptional profiling of AM obtained by bronchoalveolar lavage of 24 healthy nonsmokers, 34 healthy smokers, and 12 COPD smokers was performed to test the hypothesis whether smoking alters AM polarization, resulting in a disease-relevant activation phenotype. The analysis revealed that AM of healthy smokers exhibited a unique polarization pattern characterized by substantial suppression of M1-related inflammatory/immune genes and induction of genes associated with various M2-polarization programs relevant to tissue remodeling and immunoregulation. Such reciprocal changes progressed with the development of COPD, with M1-related gene expression being most dramatically down-regulated (p < 0.0001 vs healthy nonsmokers, p < 0.002 vs healthy smokers). Results were confirmed with TaqMan real-time PCR and flow cytometry. Among progressively down-regulated M1-related genes were those encoding type I chemokines CXCL9, CXCL10, CXCL11, and CCL5. Progressive activation of M2-related program was characterized by induction of tissue remodeling and immunoregulatory genes such as matrix metalloproteinase (MMP)2, MMP7, and adenosine A3 receptor (ADORA3). Principal component analysis revealed that differential expression of polarization-related genes has substantial contribution to global AM phenotypes associated with smoking and COPD. In summary, the data provide transcriptome-based evidence that AM likely contribute to COPD pathogenesis in a noninflammatory manner due to their smoking-induced reprogramming toward M1-deactivated, partially M2-polarized macrophages.


Assuntos
Polaridade Celular/imunologia , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/patologia , Doença Pulmonar Obstrutiva Crônica/imunologia , Doença Pulmonar Obstrutiva Crônica/patologia , Fumar/imunologia , Fumar/patologia , Adulto , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Feminino , Regulação da Expressão Gênica/imunologia , Humanos , Mediadores da Inflamação/farmacologia , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/patologia , Macrófagos Alveolares/classificação , Macrófagos Alveolares/metabolismo , Masculino , Pessoa de Meia-Idade , Nicotina/administração & dosagem , Análise de Sequência com Séries de Oligonucleotídeos , Doença Pulmonar Obstrutiva Crônica/etiologia
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