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1.
Nature ; 2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35301499
2.
Cell Death Dis ; 12(11): 1040, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34725334

RESUMO

Calcium/calmodulin-dependent protein kinase kinase 2 (CaMKK2) regulates cell and whole-body metabolism and supports tumorigenesis. The cellular impacts of perturbing CAMKK2 expression are, however, not yet fully characterised. By knocking down CAMKK2 levels, we have identified a number of significant subcellular changes indicative of perturbations in vesicle trafficking within the endomembrane compartment. To determine how they might contribute to effects on cell proliferation, we have used proteomics to identify Gemin4 as a direct interactor, capable of binding CAMKK2 and COPI subunits. Prompted by this, we confirmed that CAMKK2 knockdown leads to concomitant and significant reductions in δ-COP protein. Using imaging, we show that CAMKK2 knockdown leads to Golgi expansion, the induction of ER stress, abortive autophagy and impaired lysosomal acidification. All are phenotypes of COPI depletion. Based on our findings, we hypothesise that CAMKK2 sustains cell proliferation in large part through effects on organelle integrity and membrane trafficking.


Assuntos
Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/metabolismo , Complexo de Golgi/metabolismo , Neoplasias/enzimologia , Neoplasias/patologia , Vesículas Transportadoras/metabolismo , Ácidos/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Autofagia , Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/química , Linhagem Celular Tumoral , Proliferação de Células , Complexo I de Proteína do Envoltório/metabolismo , Sequência Conservada , Complexo de Golgi/ultraestrutura , Homeostase , Humanos , Lisossomos/metabolismo , Antígenos de Histocompatibilidade Menor/química , Antígenos de Histocompatibilidade Menor/metabolismo , Peptídeos/metabolismo , Ligação Proteica , Domínios Proteicos , RNA Interferente Pequeno/metabolismo , Ribonucleoproteínas Nucleares Pequenas/química , Ribonucleoproteínas Nucleares Pequenas/metabolismo , Resposta a Proteínas não Dobradas
3.
J Psychopharmacol ; 35(5): 547-555, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32538252

RESUMO

BACKGROUND: 3,4-Methylenedioxymethamphetamine (MDMA) is being actively researched as an adjunct to psychotherapy. It may be beneficial to trust, empathy and cooperative behaviour due to its acute prosocial effects. AIM: To test (a) the acute effects of MDMA on measures of empathy, trust and cooperative behaviour, and (b) subacute changes in mood three days after MDMA administration. METHODS: Twenty-five participants (n=7 female), participated in this double-blind, repeated-measures, placebo-controlled experiment. Participants attended two acute sessions, one week apart. Each acute session was followed by a subacute session three days later. Participants received placebo (100 mg ascorbic acid) during one acute session, and MDMA (100 mg MDMA-HCl) at the other, with order counterbalanced. Participants completed the following tasks assessing prosocial behaviour: a trust investment task, a trustworthy face rating task, an empathic stories task, a public project game, a dictator game and an ultimatum game. Participants reported subjective effects. Blood was taken pre-drug, 2 and 4 hours post-drug, and tested for plasma MDMA levels. RESULTS: MDMA acutely increased self-reported 'closeness to others' and 'euphoria' and increased plasma concentrations of MDMA. MDMA did not significantly change task-based empathy, trust or cooperative behaviour. Using Bayesian analyses, we found evidence that MDMA and placebo did not differ in their effects on empathy and cooperative behaviour. MDMA did not significantly change subacute mood and this was supported by our Bayesian analyses. CONCLUSION: Despite augmentation in plasma MDMA levels and subjective drug effects, we found no increase in prosocial behaviour in a laboratory setting.


Assuntos
Afeto/efeitos dos fármacos , Empatia/efeitos dos fármacos , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , Confiança/psicologia , Adulto , Teorema de Bayes , Comportamento Cooperativo , Método Duplo-Cego , Feminino , Alucinógenos/sangue , Alucinógenos/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade , N-Metil-3,4-Metilenodioxianfetamina/sangue , Comportamento Social , Adulto Jovem
5.
J Diabetes Sci Technol ; 14(5): 912-916, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32059615

RESUMO

The OneTouch Verio Reflect blood glucose monitor (BGM) has market clearance in several countries based in part on fulfilling the lay user and system accuracy criteria described in ISO15197:2015. However, the Food and Drug Administration (FDA) does not recognize the accuracy criteria in ISO15197 as a basis for gaining regulatory clearance for these devices. The current study evaluates the BGM using the accuracy guidelines issued by the agency for self-monitoring blood glucose test systems for over-the-counter use. Glucose results were accurate vs comparator over a wide glucose range and met lay user and glucose accuracy criteria at extreme glucose values as described in the FDA guidance.Clinicaltrials.gov NCT03851549.


Assuntos
Automonitorização da Glicemia/instrumentação , Automonitorização da Glicemia/normas , Glicemia/metabolismo , Aprovação de Equipamentos/normas , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 2/diagnóstico , Monitorização Ambulatorial/instrumentação , Monitorização Ambulatorial/normas , United States Food and Drug Administration/normas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 2/sangue , Feminino , Alemanha , Humanos , Masculino , Teste de Materiais , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Fatores de Tempo , Estados Unidos , Adulto Jovem
6.
J Diabetes Sci Technol ; 14(2): 318-323, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31375031

RESUMO

BACKGROUND: Accurate self-monitoring of blood glucose (SMBG) is a key component of effective self-management of glycemic control. METHODS: The OneTouch Verio Reflect and OneTouch Ultra Plus Reflect BG monitoring systems were evaluated for accuracy in a clinical setting. Subjects also used the meters for a one-week trial period and reported their level of satisfaction with meter features. RESULTS: Both systems were accurate over a wide glucose range and met lay user and system accuracy BG standards described in ISO15197:2015. Subjects felt that the features of a meter with a dynamic color range indicator and personalized guidance, insight, and encouragement could provide significant benefits to them in the management of their diabetes. CONCLUSIONS: Both meter systems were accurate over a wide glucose range and the features of the meter and messages were well received by patients in a short take-home trial. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov NCT0351542.


Assuntos
Glicemia/análise , Controle Glicêmico/instrumentação , Satisfação do Paciente , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Automonitorização da Glicemia/instrumentação , Automonitorização da Glicemia/psicologia , Automonitorização da Glicemia/normas , Confiabilidade dos Dados , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 2/sangue , Feminino , Controle Glicêmico/psicologia , Guias como Assunto/normas , Humanos , Masculino , Pessoa de Meia-Idade , Motivação/fisiologia , Participação do Paciente/métodos , Participação do Paciente/psicologia , Medicina de Precisão/instrumentação , Medicina de Precisão/psicologia , Reprodutibilidade dos Testes , Envio de Mensagens de Texto/instrumentação , Envio de Mensagens de Texto/normas , Tecnologia sem Fio/instrumentação , Adulto Jovem
7.
Nature ; 550(7677): 481-486, 2017 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-29045389

RESUMO

Ubiquitination controls the stability of most cellular proteins, and its deregulation contributes to human diseases including cancer. Deubiquitinases remove ubiquitin from proteins, and their inhibition can induce the degradation of selected proteins, potentially including otherwise 'undruggable' targets. For example, the inhibition of ubiquitin-specific protease 7 (USP7) results in the degradation of the oncogenic E3 ligase MDM2, and leads to re-activation of the tumour suppressor p53 in various cancers. Here we report that two compounds, FT671 and FT827, inhibit USP7 with high affinity and specificity in vitro and within human cells. Co-crystal structures reveal that both compounds target a dynamic pocket near the catalytic centre of the auto-inhibited apo form of USP7, which differs from other USP deubiquitinases. Consistent with USP7 target engagement in cells, FT671 destabilizes USP7 substrates including MDM2, increases levels of p53, and results in the transcription of p53 target genes, induction of the tumour suppressor p21, and inhibition of tumour growth in mice.


Assuntos
Piperidinas/farmacologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Peptidase 7 Específica de Ubiquitina/antagonistas & inibidores , Animais , Apoenzimas/antagonistas & inibidores , Apoenzimas/química , Apoenzimas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Feminino , Humanos , Camundongos , Modelos Moleculares , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Neoplasias/patologia , Piperidinas/síntese química , Proteínas Proto-Oncogênicas c-mdm2/química , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Pirazóis/síntese química , Pirimidinas/síntese química , Especificidade por Substrato , Transcrição Gênica/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Peptidase 7 Específica de Ubiquitina/química , Peptidase 7 Específica de Ubiquitina/metabolismo , Ubiquitinação/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Indian J Endocrinol Metab ; 21(2): 322-328, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28459033

RESUMO

BACKGROUND: Accurate self-monitoring of blood glucose (BG) is a key component of effective self-management of glycemic control. METHODS: The OneTouch Select Plus Simple™ (OTSPS) BG monitoring system (BGMS) was evaluated for accuracy in a clinical setting. RESULTS: OTSPS was accurate over a wide glucose range and met lay user and system accuracy BG standards described in ISO 15197:2013. Patients also used OTSPS for a 1-week trial period and reported their level of satisfaction with meter features. In a separate study, health-care professionals (HCPs) in India naïve to OTSPS experienced OTSPS online using a variety of interactive demonstrations of the BGMS and answered questions about its potential utility to their patients. SUMMARY: Patients and HCPs felt the features of OTSPS, including a color range indicator, could provide significant benefits to them and their patients.

9.
Expert Rev Med Devices ; 13(7): 619-26, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27232211

RESUMO

Accurate self-monitoring of blood glucose is a key component of effective self-management of glycemic control. The OneTouch VerioFlex(™) (OTVF) blood glucose monitoring system (BGMS) was evaluated for accuracy in a clinical setting. Patients also used OTVF for a 1-wk trial period and reported their level of satisfaction with meter features. In a separate study, healthcare professionals used an on-line simulator of the BGMS and answered questions about its potential utility to their patients. OTVF was accurate over a wide glucose range and met lay user and system accuracy blood glucose standards described in ISO15197:2013 as well as the accuracy requirements to fulfill US FDA expectations for 510(k) clearance of BGMS. Patients and healthcare professionals felt the features of OTVF, which has the capability to connect wirelessly to mobile devices and interact wirelessly with diabetes management software, could provide significant benefits to them or their patients.


Assuntos
Automonitorização da Glicemia/instrumentação , Glicemia/análise , Pessoal de Saúde , Satisfação do Paciente , Satisfação Pessoal , Tecnologia sem Fio/instrumentação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Automonitorização da Glicemia/efeitos adversos , Cor , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Biol Psychiatry ; 78(8): 554-62, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24495461

RESUMO

BACKGROUND: The compound 3,4-methylenedioxymethamphetamine (MDMA) is a potent monoamine releaser that produces an acute euphoria in most individuals. METHODS: In a double-blind, placebo-controlled, balanced-order study, MDMA was orally administered to 25 physically and mentally healthy individuals. Arterial spin labeling and seed-based resting state functional connectivity (RSFC) were used to produce spatial maps displaying changes in cerebral blood flow (CBF) and RSFC after MDMA administration. Participants underwent two arterial spin labeling and two blood oxygen level-dependent scans in a 90-minute scan session; MDMA and placebo study days were separated by 1 week. RESULTS: Marked increases in positive mood were produced by MDMA. Decreased CBF only was observed after MDMA, and this was localized to the right medial temporal lobe (MTL), thalamus, inferior visual cortex, and the somatosensory cortex. Decreased CBF in the right amygdala and hippocampus correlated with ratings of the intensity of global subjective effects of MDMA. The RSFC results complemented the CBF results, with decreases in RSFC between midline cortical regions, the medial prefrontal cortex, and MTL regions, and increases between the amygdala and hippocampus. There were trend-level correlations between these effects and ratings of intense and positive subjective effects. CONCLUSIONS: The MTLs appear to be specifically implicated in the mechanism of action of MDMA, but further work is required to elucidate how the drug's characteristic subjective effects arise from its modulation of spontaneous brain activity.


Assuntos
Afeto/fisiologia , Tonsila do Cerebelo/efeitos dos fármacos , N-Metil-3,4-Metilenodioxianfetamina/administração & dosagem , Oxigênio/sangue , Serotoninérgicos/administração & dosagem , Adulto , Circulação Cerebrovascular/efeitos dos fármacos , Método Duplo-Cego , Feminino , Voluntários Saudáveis , Hipocampo/efeitos dos fármacos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Córtex Pré-Frontal/efeitos dos fármacos , Lobo Temporal/efeitos dos fármacos , Adulto Jovem
12.
J Exp Psychol Gen ; 141(4): 715-27, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22468670

RESUMO

It has been proposed that two major axes, dominance and trustworthiness, characterize the social dimensions of face evaluation. Whether evaluation of faces on these social dimensions is restricted to conscious appraisal or happens at a preconscious level is unknown. Here we provide behavioral evidence that such preconscious evaluations exist and that they are likely to be interpretations arising from interactions between the face stimuli and observer-specific traits. Monocularly viewed faces that varied independently along two social dimensions of trust and dominance were rendered invisible by continuous flash suppression (CFS) when a flashing pattern was presented to the other eye. Participants pressed a button as soon as they saw the face emerge from suppression to indicate whether the previously hidden face was located slightly to the left or right of central fixation. Dominant and untrustworthy faces took significantly longer time to emerge (T2E) compared with neutral faces. A control experiment showed these findings could not reflect delayed motor responses to conscious faces. Finally, we showed that participants' self-reported propensity to trust was strongly predictive of untrust avoidance (i.e., difference in T2E for untrustworthy vs neutral faces) as well as dominance avoidance (i.e., difference in T2E for dominant vs neutral faces). Dominance avoidance was also correlated with submissive behavior. We suggest that such prolongation of suppression for threatening faces may result from a passive fear response, leading to slowed visual perception.


Assuntos
Face , Expressão Facial , Reconhecimento Visual de Modelos/fisiologia , Percepção Social , Inconsciente Psicológico , Adolescente , Adulto , Tonsila do Cerebelo/fisiologia , Feminino , Humanos , Julgamento , Masculino , Testes Neuropsicológicos , Predomínio Social , Confiança/psicologia , Adulto Jovem
13.
Brain Lang ; 114(2): 126-34, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20096448

RESUMO

Hemispherectomy (disconnection or removal of an entire cerebral hemisphere) is a rare surgical procedure used for the relief of drug-resistant epilepsy in children. After hemispherectomy, contralateral hemiplegia persists whereas gross expressive and receptive language functions can be remarkably spared. Motor speech deficits have rarely been examined systematically, thus limiting the accuracy of postoperative prognosis. We describe the speech profiles of hemispherectomized participants characterizing their intelligibility, articulation, phonological speech errors, dysarthric features, and execution and sequencing of orofacial speech and non-speech movements. Thirteen participants who had undergone hemispherectomy (six left, seven right; nine with congenital, four with acquired hemiplegia; operated between four months and 13 years) were investigated. Results showed that all participants were intelligible but showed a mild dysarthric profile characterized by neuromuscular asymmetry and reduced quality and coordination of movements, features that are characteristic of adult-onset unilateral upper motor neuron dysarthria, flaccid-ataxic variant. In addition, one left and four right hemispherectomy cases presented with impaired production of speech and non-speech sequences. No participant showed evidence of verbal or oral dyspraxia. It is concluded that mild dysarthria is persistent after left or right hemispherectomy, irrespective of age at onset of hemiplegia. These results indicate incomplete functional re-organization for the control of fine speech motor movements throughout childhood, and provide no evidence of hemispheric differences.


Assuntos
Disartria/fisiopatologia , Epilepsia/cirurgia , Hemisferectomia , Complicações Pós-Operatórias/fisiopatologia , Percepção da Fala/fisiologia , Fala/fisiologia , Adolescente , Criança , Pré-Escolar , Disartria/etiologia , Feminino , Hemiplegia/etiologia , Hemiplegia/fisiopatologia , Humanos , Lactente , Desenvolvimento da Linguagem , Masculino , Plasticidade Neuronal/fisiologia , Recuperação de Função Fisiológica/fisiologia , Testes de Articulação da Fala , Inteligibilidade da Fala/fisiologia , Adulto Jovem
14.
J Abnorm Psychol ; 118(4): 767-77, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19899846

RESUMO

Differences in symptoms, trauma exposure, dissociative and emotional reactions to trauma, and subsequent life stress in war veterans reporting immediate-onset or delayed-onset posttraumatic stress disorder (PTSD) or no PTSD were investigated. The role of life stress in delayed-onset PTSD was also studied. Retrospective interviews were conducted with 142 United Kingdom veterans receiving a war pension for PTSD or physical disability. Immediate-onset and delayed-onset PTSD were similar in the number and type of symptoms reported at onset, but the delayed-onset group differed in showing a gradual accumulation of symptoms that began earlier and continued throughout their military career. They were more likely to report major depressive disorder and alcohol abuse prior to PTSD onset. Both groups described similar amounts of trauma exposure, but those in the delayed-onset group reported significantly less peritraumatic dissociation, anger, and shame. Veterans with delayed onsets were more likely than veterans with no PTSD to report the presence of a severe life stressor in the year before onset. In conclusion, the results suggest that delayed onsets involve a more general stress sensitivity and a progressive failure to adapt to continued stress exposure.


Assuntos
Distúrbios de Guerra/diagnóstico , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Traumático Agudo/diagnóstico , Veteranos/psicologia , Adaptação Psicológica , Adulto , Ira , Distúrbios de Guerra/psicologia , Feminino , Seguimentos , Humanos , Entrevista Psicológica , Acontecimentos que Mudam a Vida , Masculino , Fatores de Risco , Vergonha , Meio Social , Transtornos de Estresse Pós-Traumáticos/psicologia , Transtornos de Estresse Traumático Agudo/psicologia , Fatores de Tempo
15.
Eur J Cancer ; 44(13): 1883-94, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18657413

RESUMO

Tumour growth is dependent on angiogenesis, the key mediator of which is vascular endothelial growth factor-A (VEGF-A). VEGF-A exists as two families of alternatively spliced isoforms - pro-angiogenic VEGF(xxx) generated by proximal, and anti-angiogenic VEGF(xxx)b by distal splicing of exon 8. VEGF(165)b inhibits angiogenesis and is downregulated in tumours. Here, we show for the first time that administration of recombinant human VEGF(165)b inhibits colon carcinoma tumour growth and tumour vessel density in nude mice, with a terminal plasma half-life of 6.2h and directly inhibited angiogenic parameters (endothelial sprouting, orientation and structure formation) in vitro. Intravenous injection of (125)I-VEGF(165)b demonstrated significant tumour uptake lasting at least 24h. No adverse effects on liver function or haemodynamics were observed. These results indicate that injected VEGF(165)b was taken up into the tumour as an effective anti-angiogenic cancer therapy, and provide proof of principle for the development of this anti-angiogenic growth factor splice isoform as a novel cancer therapy.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Neoplasias do Colo/tratamento farmacológico , Fator A de Crescimento do Endotélio Vascular/administração & dosagem , Inibidores da Angiogênese/efeitos adversos , Inibidores da Angiogênese/farmacocinética , Animais , Pressão Sanguínea , Divisão Celular/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas , Neoplasias do Colo/irrigação sanguínea , Neoplasias do Colo/patologia , Ensaio de Imunoadsorção Enzimática , Injeções Subcutâneas , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Transplante de Neoplasias , Neovascularização Patológica/prevenção & controle , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/farmacocinética , Fator A de Crescimento do Endotélio Vascular/efeitos adversos , Fator A de Crescimento do Endotélio Vascular/farmacocinética
16.
Am J Psychiatry ; 164(9): 1319-26, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17728415

RESUMO

OBJECTIVE: Since the diagnosis of delayed-onset posttraumatic stress disorder (PTSD) was introduced in DSM-III, there has been controversy over its prevalence and even its existence. The authors sought to resolve discrepant findings concerning the prevalence of delayed-onset PTSD by conducting a systematic review of the evidence. METHOD: A literature search was conducted for case reports and group studies with adequate measurement of delayed-onset PTSD according to DSM criteria. Studies that met inclusion criteria were examined for the defined length of delay for delayed-onset PTSD, presence of symptoms before full diagnostic criteria were met, length of follow-up, prevalence estimates, and other variables. Studies were also examined for differences between immediate-onset PTSD, delayed-onset PTSD, and no-PTSD cases. RESULTS: Ten case studies and 19 group studies met criteria for inclusion in the review. Studies consistently showed that delayed-onset PTSD in the absence of any prior symptoms was rare, whereas delayed onsets that represented exacerbations or reactivations of prior symptoms accounted on average for 38.2% and 15.3%, respectively, of military and civilian cases of PTSD. CONCLUSIONS: The discrepant findings in the literature concerning prevalence can be largely, but not completely, explained as being due to definitional issues. Little is known about what distinguishes the delayed-onset and immediate-onset forms of the disorder. Continuing scientific study of delayed-onset PTSD would benefit if future editions of DSM were to adopt a definition that explicitly accepts the likelihood of at least some prior symptoms.


Assuntos
Transtornos de Estresse Pós-Traumáticos/epidemiologia , Idade de Início , Manual Diagnóstico e Estatístico de Transtornos Mentais , Seguimentos , Humanos , Prevalência , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Projetos de Pesquisa , Transtornos de Estresse Pós-Traumáticos/diagnóstico
17.
FASEB J ; 19(1): 121-3, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15486058

RESUMO

Roundabout receptors are molecular guidance molecules that function by interaction with Slit proteins to regulate axon guidance, neuronal migration, and leukocyte chemotaxis. We recently isolated a novel roundabout gene, called Robo4, which is restricted in expression to the endothelium, notably in areas of angiogenesis. The aim of this study was to use the soluble extracellular domain of Robo4 as a probe of function in angiogenesis and endothelial biology. Thus, the soluble extracellular domain of the receptor (Robo4Fc) showed diverse in vivo and in vitro activities including 1) inhibition of angiogenesis in vivo in the rodent subcutaneous sponge model, 2) inhibition of tube formation in the rat aortic ring assay, 3) inhibition of VEGF- and bFGF-stimulated endothelial cell migration, and 4) inhibition of endothelial proliferation. To assess whether Robo4Fc was inhibiting Slit-mediated effects, we determined whether Robo4 and Slit interact. Recombinant Slits-1, -2, and -3 were shown by immunoprecipitation and BiaCore analysis to bind to Robo1 but not Robo4. Further study of the role of Robo4 in angiogenesis appears justified.


Assuntos
Células Endoteliais/metabolismo , Neovascularização Patológica/metabolismo , Neovascularização Fisiológica/fisiologia , Receptores de Superfície Celular/metabolismo , Animais , Movimento Celular/fisiologia , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Humanos , Fragmentos de Imunoglobulinas/genética , Peptídeos e Proteínas de Sinalização Intercelular , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/irrigação sanguínea , Neoplasias/metabolismo , Neovascularização Patológica/prevenção & controle , Proteínas do Tecido Nervoso/metabolismo , Peptídeos/metabolismo , Estrutura Terciária de Proteína , Receptores de Superfície Celular/genética , Receptores Imunológicos/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Solubilidade , Veias Umbilicais/citologia , Proteínas Roundabout
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