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1.
Foot Ankle Surg ; 28(1): 20-24, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33500217

RESUMO

BACKGROUND: The use of smartphones and multimedia messaging service (MMS) continues to increase in day to day orthopaedic clinical practice. However, there is limited evidence to support the safe utilisation of MMS. OBJECTIVES: The aim of this study was to correlate the performance of MMS imaging to picture archiving and communication systems (PACS) imaging within the setting of diagnosis and management of ankle fractures. METHODS: The ankle fracture radiograph series of 82 consecutive patients were evaluated by five orthopaedic consultant specialists. A questionnaire regarding diagnosis and preferred management was completed separately for each patient using smartphone and PACS images. Statistical analysis was performed using Intraclass Correlation Coefficient (ICC). RESULTS: Ankle fracture diagnosis showed strong to excellent correlation both inter- and intraobserver MMS vs PACS when using the Weber (0.815, 0.988), Anatomical (0.858, 0.988), and AO classification systems (0.855, 0.985). MMS was less reliable than PACS in determining many management options. CONCLUSION: The reliability of ankle fracture classification using MMS image viewing was not significantly different to interpretation on PACS workstations. Smartphone use in ankle fracture classification is supported by this study. Smartphone use was less accurate than PACS in devising management plans and future use should be limited to making only initial plans that must be corroberated with PACS and intraoperative findings prior to definitive fixation.


Assuntos
Fraturas do Tornozelo , Smartphone , Fraturas do Tornozelo/diagnóstico por imagem , Fraturas do Tornozelo/cirurgia , Humanos , Multimídia , Radiografia , Reprodutibilidade dos Testes
3.
Dis Esophagus ; 30(11): 1-8, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28881905

RESUMO

The treatment of esophageal perforation (EP) remains a significant clinical challenge. While a number of investigators have previously documented efficient approaches, these were mostly single-center experiences reported prior to the introduction of newer technologies: specifically endoluminal stents. This study was designed to document contemporary practice in the diagnosis and management of EP at multiple institutions around the world and includes early clinical outcomes. A five-year (2009-2013) multicenter retrospective review of management and outcomes for patients with thoracic or abdominal esophageal perforation was conducted. Demographics, etiology, diagnostic modalities, treatments, subsequent early outcomes as well as morbidity and mortality were captured and analyzed. During the study period, 199 patients from 10 centers in the United States, Canada, and Europe were identified. Mechanisms of perforation included Boerhaave syndrome (60, 30.1%), iatrogenic injury (65, 32.6%), and penetrating trauma (25, 12.6%). Perforation was isolated to the thoracic segment alone in 124 (62.3%), with 62 (31.2%) involving the thoracoabdominal esophagus. Mean perforation length was 2.5 cm. Observation was selected as initial management in 65 (32.7%), with only two failures. Direct operative intervention was initial management in 65 patients (32.6%), while 29 (14.6%) underwent esophageal stent coverage. Compared to operative intervention, esophageal stent patients were significantly more likely to be older (61.3 vs. 48.3 years old, P < 0.001) and have sustained iatrogenic mechanisms of esophageal perforation (48.3% vs.15.4%). Secondary intervention requirement for patients with perforation was 33.7% overall (66). Complications included sepsis (56, 28.1%), pneumonia (34, 17.1%) and multi-organ failure (23, 11.6%). Overall mortality was 15.1% (30). In contemporary practice, diagnostic and management approaches to esophageal perforation vary widely. Despite the introduction of endoluminal strategies, it continues to carry a high risk of mortality, morbidity, and need for secondary intervention. A concerted multi-institutional, prospectively collected database is ideal for further investigation.


Assuntos
Perfuração Esofágica/cirurgia , Esofagoscopia/métodos , Adulto , Idoso , Canadá , Perfuração Esofágica/etiologia , Esofagoscopia/efeitos adversos , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Stents , Resultado do Tratamento , Estados Unidos
4.
Biochem J ; 469(2): 289-98, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25990325

RESUMO

Activity of FOXO (forkhead box O) transcription factors is inhibited by growth factor-PI3K (phosphoinositide 3-kinase)-PKB (protein kinase B)/Akt signalling to control a variety of cellular processes including cell cycle progression. Through comparative analysis of a number of microarray datasets we identified a set of genes commonly regulated by FOXO proteins and PI3K-PKB/Akt, which includes CTDSP2 (C-terminal domain small phosphatase 2). We validated CTDSP2 as a genuine FOXO target gene and show that ectopic CTDSP2 can induce cell cycle arrest. We analysed transcriptional regulation after CTDSP2 expression and identified extensive regulation of genes involved in cell cycle progression, which depends on the phosphatase activity of CTDSP2. The most notably regulated gene is the CDK (cyclin-dependent kinase) inhibitor p21(Cip1/Waf1) and in the present study we show that p21(Cip1/Waf1) is partially responsible for the cell cycle arrest through decreasing cyclin-CDK activity. Our data suggest that CTDSP2 induces p21(Cip1/Waf1) through increasing the activity of Ras. As has been described previously, Ras induces p21(Cip1/Waf1) through p53-dependent and p53-independent pathways and indeed both p53 and MEK inhibition can mitigate the CTDSP2-induced p21(Cip1/Waf1) mRNA up-regulation. In support of Ras activation by CTDSP2, depletion of endogenous CTDSP2 results in reduced Ras activity and thus CTDSP2 seems to be part of a larger set of genes regulated by FOXO proteins, which increase growth factor signalling upon FOXO activation.


Assuntos
Pontos de Checagem do Ciclo Celular/fisiologia , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Proteínas Nucleares/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Proteínas ras/metabolismo , Animais , Inibidor de Quinase Dependente de Ciclina p21/genética , Fatores de Transcrição Forkhead/genética , Regulação da Expressão Gênica/fisiologia , Células HEK293 , Humanos , Camundongos , Camundongos Knockout , Células NIH 3T3 , Proteínas Nucleares/genética , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fosfoproteínas Fosfatases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transcrição Gênica/fisiologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas ras/genética
5.
Proc Natl Acad Sci U S A ; 110(41): 16645-50, 2013 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-24062441

RESUMO

Much of what is known about the neurobiology of learning and memory comes from studies of the average behavior. In contrast, intersubject differences that emerge within groups are difficult to study systematically and are often excluded from scientific discussion. Nevertheless, population-wide variability is a virtually universal feature of both complex traits, such as intelligence, and hardwired responses, such as defensive behaviors. Here, we use outbred rats to investigate if cAMP response element-binding protein (CREB), a transcription factor that has long been known in experimental settings to be crucial for associative plasticity, participates in natural memory phenotypes. Using a combination of behavioral, biochemical, and viral techniques, we show that a subset of rats with trait-like deficits in aversive memory have basally reduced CREB activity in the lateral amygdala but can be induced to perform at average levels by directly or indirectly enhancing pretraining CREB phosphorylation. These data suggest that endogenous CREB activity in the amygdala may set a critical threshold for plasticity during memory formation.


Assuntos
Tonsila do Cerebelo/fisiologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Emoções/fisiologia , Memória/fisiologia , Plasticidade Neuronal/fisiologia , Estimulação Acústica , Tonsila do Cerebelo/metabolismo , Análise de Variância , Animais , Western Blotting , Clonagem Molecular , Condicionamento Psicológico , Masculino , Fosforilação , Estimulação Luminosa , Ratos , Ratos Sprague-Dawley
6.
Learn Mem ; 20(12): 695-9, 2013 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-24255099

RESUMO

In reconsolidation studies, memories are typically retrieved by an exposure to a single conditioned stimulus (CS). We have previously demonstrated that reconsolidation processes are CS-selective, suggesting that memories retrieved by the CS exposure are discrete and reconsolidate separately. Here, using a compound stimulus in which two distinct CSs are concomitantly paired with the same aversive unconditioned stimulus (US), we show in rats that reexposure to one of the components of the compound CS triggers extinction or reconsolidation of the other component. This suggests that the original training conditions play a critical role in memory retrieval and reconsolidation.


Assuntos
Condicionamento Clássico/fisiologia , Extinção Psicológica/fisiologia , Medo , Memória/fisiologia , Tonsila do Cerebelo/efeitos dos fármacos , Tonsila do Cerebelo/fisiologia , Animais , Anisomicina/farmacologia , Condicionamento Clássico/efeitos dos fármacos , Extinção Psicológica/efeitos dos fármacos , Medo/efeitos dos fármacos , Masculino , Memória/efeitos dos fármacos , Inibidores da Síntese de Proteínas/farmacologia , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
7.
Biochim Biophys Acta ; 1813(11): 1926-37, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21539865

RESUMO

Aging is characterized by the general decline in tissue and body function and the increased susceptibility to age-related pathologies, such as cancer. To maintain optimal tissue and body function, organisms have developed complex mechanisms for tissue homeostasis. Importantly, it is becoming apparent that these same mechanisms when deregulated also result in the development of age-related disease. The build in fail safe mechanisms of homeostasis, which prevent skewing toward disease, themselves contribute to aspects of aging. Thus, longevity is limited by an intrinsic trade-off between optimal tissue function and disease. Consequently, aging and age-related diseases, such as cancer and diabetes are driven by the same genetic determinants. Illustrative in this respect is the insulin/IGF-1 signaling pathway acting through PI3K/PKB and FOXO. Loss of PKB signaling contributes to diabetes, whereas gain of function of PKB drives cancer. Enhanced FOXO activity, at least in model organism contributes to extended lifespan and acts as a tumor suppressive mechanism. Here, we focus on the linkage between PKB and FOXO as a central switch in contributing to tissue homeostasis and age-related diseases in particular cancer. This article is part of a Special Issue entitled: P13K-AKT-FoxO axis in cancer and aging.


Assuntos
Envelhecimento/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Neoplasias/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Proteínas de Ciclo Celular/metabolismo , Proteína Forkhead Box O1 , Humanos , Modelos Biológicos , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteína Supressora de Tumor p53/metabolismo
8.
Fungal Genet Biol ; 49(8): 619-25, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22691725

RESUMO

We have inserted a histone H1-GFP fusion gene adjacent to three loci on different chromosomes of Neurospora crassa and made mating pairs in which a wild type version of GFP is crossed to one with a mutation in the 5' end of GFP. The loci are his-3, am and his-5, chosen because recombination mechanisms appear to differ between his-3 and am, and because crossing over adjacent to his-5, like his-3, is regulated by rec-2. At his-3, the frequencies of crossing over between GFP and the centromere and of conversion of 5'GFP to GFP(+) are comparable to those obtained by classical recombination assays, as is the effect of rec-2 on these frequencies, suggesting that our system does not alter the process of recombination. At each locus we have obtained sufficient data, on both gene conversion and crossing over, to be able to assess the effect of deletion of any gene involved in recombination. In addition, crosses between a GFP(+) strain and one with normal sequence at all three loci have been used to measure the interval to the centromere and to show that GFP experiences gene conversion with this system. Since any gene expressed in meiosis is silenced in Neurospora if hemizygous, any of our GFP(+) strains can be used as a quick screen to determine if a gene deleted by the Neurospora Genome Project is involved in crossing over or gene conversion.


Assuntos
Troca Genética , Loci Gênicos , Proteínas de Fluorescência Verde/genética , Neurospora crassa/genética , Alelos , Cromossomos Fúngicos , Proteínas Fúngicas/metabolismo , Conversão Gênica , Proteínas de Fluorescência Verde/metabolismo , Hemizigoto , Histonas/genética , Mutação , Neurospora crassa/metabolismo
9.
Electrophoresis ; 33(3): 492-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22287177

RESUMO

Single primer amplification is shown to yield a DNA profile that is reproducible when based on the sequence content of the amplicons rather than on the pattern of length polymorphism. The sequence-based profile increases in reliability with increasing numbers of cycles of amplification. This process uses an arbitrarily chosen primer and a low initial annealing temperature in order to amplify sequences from the whole metagenome present in a sample that may contain only trace DNA, and a large number of cycles to select subsets of sequences based on variable amplification efficiency. Using arrays, we demonstrate the utility and limitations of this approach for profiling the large metagenomes typical of soils and the trace DNA present in drug seizures. We suggest that this type of profiling will be most effective once next-generation sequencing and advanced sequence analysis becomes routine.


Assuntos
Primers do DNA/química , DNA/análise , Técnicas de Amplificação de Ácido Nucleico/métodos , Análise de Sequência de DNA/métodos , DNA/química , DNA/metabolismo , Primers do DNA/metabolismo , Ciências Forenses , Humanos , Metagenoma , Técnicas de Amplificação de Ácido Nucleico/normas , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Análise de Sequência de DNA/normas , Solo
10.
Depress Anxiety ; 28(3): 186-93, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21394851

RESUMO

BACKGROUND: Posttraumatic stress disorder (PTSD) is associated with enhanced noradrenergic activity. Animal and human studies demonstrate that noradrenergic stimulation augments consolidation of fear learning. Retrieval of well-established memories by presenting a learned fear cue triggers reconsolidation processes during which memories may be updated, weakened, or strengthened. We previously reported that noradrenergic blockade in the rat amygdala impairs reconsolidation of fear memories. Here we investigated the effects of noradrenergic enhancement on reconsolidation of learned fear. METHODS: Using auditory fear conditioning in rats, we tested the effects of postretrieval intraamygdala infusion of the ß-adrenergic receptor agonist isoproterenol or the antagonist propranolol on conditioned fear in the amygdala. RESULTS: A single intraamygdala infusion of isoproterenol following a retrieval of a well-consolidated memory enhanced fear memory elicited by the learned fear stimulus and impaired extinction of this memory 48 hr later. Intraamygdala infusion of the ß-adrenergic receptor antagonist propranolol following a consecutive retrieval trial blocked the enhancing effects of isoproterenol on fear memory. CONCLUSIONS: Postretrieval ß-adrenergic stimulation in the amygdala enhances reconsolidation of fear memories, making them resistant to extinction. Noradrenergic augmentation during retrieval of fear memories may thus contribute to persistence and severity of traumatic memories. Reconsolidation may be a useful tool in understanding the pathology of PTSD and may thus help in developing new and in modifying existing treatments of traumatic memories.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Condicionamento Clássico/fisiologia , Extinção Psicológica/fisiologia , Medo/fisiologia , Norepinefrina/fisiologia , Retenção Psicológica/fisiologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Estimulação Acústica , Agonistas Adrenérgicos beta/farmacologia , Antagonistas Adrenérgicos beta/farmacologia , Tonsila do Cerebelo/efeitos dos fármacos , Animais , Condicionamento Clássico/efeitos dos fármacos , Sinais (Psicologia) , Extinção Psicológica/efeitos dos fármacos , Medo/efeitos dos fármacos , Humanos , Terapia Implosiva , Isoproterenol/farmacologia , Masculino , Propranolol/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores Adrenérgicos beta/efeitos dos fármacos , Receptores Adrenérgicos beta/fisiologia , Retenção Psicológica/efeitos dos fármacos , Transdução de Sinais/fisiologia
11.
Cereb Cortex ; 19(2): 474-82, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18562331

RESUMO

Fear extinction, which involves learning to suppress the expression of previously learned fear, requires N-methyl-D-aspartate receptors (NMDARs) and is mediated by the amygdala and ventromedial prefrontal cortex (vmPFC). Like other types of learning, extinction involves acquisition and consolidation phases. We recently demonstrated that NR2B-containing NMDARs (NR2Bs) in the lateral amygdala (LA) are required for extinction acquisition, but whether they are involved in consolidation is not known. Further, although it has been shown that NMDARs in the vmPFC are required for extinction consolidation, whether NR2Bs in vmPFC are involved in consolidation is not known. In this report, we investigated the possible role of LA and vmPFC NR2Bs in the consolidation of fear extinction using the NR2B-selective antagonist ifenprodil. We show that systemic treatment with ifenprodil immediately after extinction training disrupts extinction consolidation. Ifenprodil infusion into vmPFC, but not the LA, immediately after extinction training also disrupts extinction consolidation. In contrast, we also show pre-extinction training infusions into vmPFC has no effect. These results, together with our previous findings showing that LA NR2Bs are required during the acquisition phase in extinction, indicate a double dissociation for the phase-dependent role of NR2Bs in the LA (acquisition, not consolidation) and vmPFC (consolidation, not acquisition).


Assuntos
Tonsila do Cerebelo/fisiologia , Extinção Psicológica/fisiologia , Medo/fisiologia , Córtex Pré-Frontal/fisiologia , Receptores de N-Metil-D-Aspartato/fisiologia , Tonsila do Cerebelo/efeitos dos fármacos , Animais , Interpretação Estatística de Dados , Antagonistas de Aminoácidos Excitatórios/farmacologia , Extinção Psicológica/efeitos dos fármacos , Medo/efeitos dos fármacos , Masculino , Plasticidade Neuronal/fisiologia , Piperidinas/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos
12.
Int J Integr Care ; 20(2): 4, 2020 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-32346362

RESUMO

INTRODUCTION: Frequent attenders to Emergency Departments (ED) often have contributing substance use disorders (SUD), but there are few evaluations of relevant interventions. We examine one such pilot assertive management service set in Sydney, Australia (IMPACT), aimed at reducing hospital presentations and costs, and improving client outcomes. METHODS: IMPACT eligibility criteria included moderate-to-severe SUD and ED attendance on ≥5 occasions in the previous year. A pre-post intervention design examined clients' presentations and outcomes 6 months before and after participation to a comparison group of eligible clients who did not engage. RESULTS: Between 2014 and 2015, 34 clients engaged in IMPACT, with 12 in the comparison group. Clients demonstrated significant reductions in preventable (p < 0.05) and non-preventable (p < 0.01) ED presentations and costs, and in hospital admissions and costs (p < 0.01). IMPACT clients also reported a significant reduction in use days for primary substance (p < 0.01). The comparison group had a significant reduction (p < 0.05) in non-preventable visits only. CONCLUSIONS: Assertive management services can be effective in preventing hospital presentations and costs for frequent ED attenders with SUDs and improving client outcomes, representing an effective integrated health approach. The IMPACT service has since been refined and integrated into routine care across a number of hospitals in Sydney, Australia.

13.
Spine (Phila Pa 1976) ; 43(2): 105-113, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-21912307

RESUMO

STUDY DESIGN: Prospective single-center case cohort study. OBJECTIVE: Evaluation of clinical and radiographic outcomes of a consecutive 122-patient cohort with discogenic back pain, at 2- to 10-year follow-up periods, treated by a single surgeon, with CHARITÉ Artificial Disc (DePuy Spine, Raynham, MA). SUMMARY OF BACKGROUND DATA: Minimum 2-year clinical and radiographic level 1 data for the first lumbar artificial disc, the CHARITÉ Artificial Disc (DePuy Spine), have recently been published, demonstrating sustained clinical benefit of the device for the treatment of degenerative disc disease. METHODS: Patients were assessed preoperatively using clinical outcome measures, including visual analog scale (VAS) score back and leg, Oswestry Disability Index (ODI), 36-Item Short Form Health Survey (SF-36), and Roland-Morris Questionnaires (RMDQ), and further assessed postoperatively, 3-, 6-, 12-months, and yearly thereafter. RESULTS: Average follow-up was 44.9 ±â€Š23.3 months (n = 122). The median age at surgery was 43.0 ±â€Š9.0 years. Preoperative diagnosis included degenerative disc disease in 118 (96.7%) and internal disc disruption in 4 (3.3%). Surgery was performed at L5-S1 in 96 (77.9%) patients and at L4-L5 in 27 (22.1%). Statistically significant clinical improvements from baseline were observed on VAS (back and leg), ODI, SF-36 PCS, SF-36 MCS, and RMDQ 3 months onward. Back VAS scores decreased from 78.2 ±â€Š21.3 preoperatively to 21.9 ±â€Š27.8 by final follow-up. ODI scores decreased from 51.1 ±â€Š17.3 to 16.2 ±â€Š17.9 at last follow-up. The RMDQ scores also decreased from 16.7 ±â€Š4.7 to 4.2 ±â€Š5.8. SF-36 PCS and MCS increased from 25.7 ±â€Š11.0 to 46.4 ±â€Š10.3 for PCS and from 35.5 ±â€Š17.4 to 51.6 ±â€Š10.8 for MCS. Patient satisfaction surveys indicated that 90.56% patients rated their satisfaction with the surgery as "excellent" or "good" at 2 years. Range of motion averaged 8.6 ±â€Š3.5 (median = 8.0°) at the last follow-up time point. CONCLUSION: Outcomes verify the clinical efficacy of total disc replacement for treatment of discogenic back pain with or without radiculopathy. The outcomes instruments demonstrated statistically significant improvements 3 months onward. LEVEL OF EVIDENCE: N/A.


Assuntos
Degeneração do Disco Intervertebral/cirurgia , Deslocamento do Disco Intervertebral/cirurgia , Dor Lombar/cirurgia , Vértebras Lombares/cirurgia , Substituição Total de Disco , Adulto , Feminino , Humanos , Degeneração do Disco Intervertebral/diagnóstico por imagem , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Dor Lombar/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Estudos Prospectivos , Radiografia , Amplitude de Movimento Articular , Inquéritos e Questionários , Resultado do Tratamento
14.
Cancer Res ; 78(9): 2356-2369, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29440168

RESUMO

FOXO transcription factors are regulators of cellular homeostasis and putative tumor suppressors, yet the role of FOXO in cancer progression remains to be determined. The data on FOXO function, particularly for epithelial cancers, are fragmentary and come from studies that focused on isolated aspects of cancer. To clarify the role of FOXO in epithelial cancer progression, we characterized the effects of inducible FOXO activation and loss in a mouse model of metastatic invasive lobular carcinoma. Strikingly, either activation or loss of FOXO function suppressed tumor growth and metastasis. We show that the multitude of cellular processes critically affected by FOXO function include proliferation, survival, redox homeostasis, and PI3K signaling, all of which must be carefully balanced for tumor cells to thrive.Significance: FOXO proteins are not solely tumor suppressors, but also support tumor growth and metastasis by regulating a multitude of cellular processes essential for tumorigenesis. Cancer Res; 78(9); 2356-69. ©2018 AACR.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Fatores de Transcrição Forkhead/metabolismo , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Modelos Animais de Doenças , Progressão da Doença , Feminino , Fatores de Transcrição Forkhead/genética , Humanos , Camundongos , Camundongos Knockout , Metástase Neoplásica , Oxirredução , Transdução de Sinais , Carga Tumoral
15.
Biol Psychiatry ; 62(10): 1111-8, 2007 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-17524369

RESUMO

BACKGROUND: Selective serotonin reuptake inhibitors (SSRIs) effectively treat various anxiety disorders, although symptoms of anxiety are often exacerbated during early stages of treatment. We previously reported that acute treatment with the SSRI citalopram enhances the acquisition of auditory fear conditioning, which is consistent with the initial anxiogenic effects reported clinically. Here, we extend our findings by assessing the effects of acute SSRI treatment on the expression of previously acquired conditioned fear. METHODS: Rats underwent fear conditioning drug-free. Tone-evoked fear responses were tested after drug treatment the following day. This protocol more closely resembles the clinical setting than pre-conditioning treatment, because it evaluates effects of treatment on a pre-existing fear rather than on the formation of a new fear memory. RESULTS: A single pre-testing injection of the SSRIs citalopram or fluoxetine significantly increased fear expression. There was no effect of the antidepressant tianeptine or the norepinephrine reuptake inhibitor tomoxetine, indicating that this effect is specific to SSRIs. The SSRI-induced enhancement in fear expression was not blocked by tropisetron, a 5-HT(3) receptor antagonist, but was blocked by SB 242084, a specific 5-HT(2C) receptor antagonist. CONCLUSIONS: Enhanced activation of 5-HT(2C) receptors might be a mechanism for the anxiogenic effects of SSRIs observed initially during treatment.


Assuntos
Condicionamento Psicológico/efeitos dos fármacos , Medo/psicologia , Indóis/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Antagonistas da Serotonina/farmacologia , Estimulação Acústica/efeitos adversos , Animais , Comportamento Animal/efeitos dos fármacos , Citalopram/farmacologia , Condicionamento Psicológico/fisiologia , Interações Medicamentosas , Fluoxetina/farmacologia , Reação de Congelamento Cataléptica/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Tropizetrona
16.
Neuropsychopharmacology ; 32(9): 1929-40, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17213844

RESUMO

N-methyl-D-aspartate receptors (NMDARs) contribute to synaptic plasticity underlying learning in a variety of brain systems. Fear extinction, which involves learning to suppress the expression of previously learned fear, appears to require NMDAR activation in the amygdala. However, it is unclear whether amygdala NMDARs are required for the acquisition of extinction learning, and it is unknown whether NR2B-containing NMDARs are required in fear extinction. Here, we assessed the effects of selective NR2B blockade with ifenprodil on fear extinction learning, and found that both systemic and intra-amygdala ifenprodil treatment, given before extinction training, impaired the initial acquisition, and subsequent retrieval of fear extinction. These results confirm previous evidence showing that NMDARs in the amygdala are involved in fear extinction, and additionally show that NR2B-containing NMDARs are required. Contrary to the conclusion of previous studies, our findings demonstrate NMDARs are required for the initial acquisition, rather than only the retention, of fear extinction learning. Thus, our results support a previously not known role for NMDA-dependent plasticity in the lateral amygdala during the acquisition of fear extinction.


Assuntos
Tonsila do Cerebelo/fisiologia , Condicionamento Clássico/fisiologia , Extinção Psicológica/fisiologia , Medo , Receptores de N-Metil-D-Aspartato/fisiologia , Tonsila do Cerebelo/efeitos dos fármacos , Análise de Variância , Animais , Comportamento Animal/efeitos dos fármacos , Condicionamento Clássico/efeitos dos fármacos , Vias de Administração de Medicamentos , Antagonistas de Aminoácidos Excitatórios/farmacologia , Extinção Psicológica/efeitos dos fármacos , Reação de Congelamento Cataléptica/efeitos dos fármacos , Reação de Congelamento Cataléptica/fisiologia , Masculino , Piperidinas/farmacologia , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
17.
Neuropharmacology ; 52(1): 228-33, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16926033

RESUMO

A central question in the study of LTP has been to determine what role it plays in memory formation and storage. One valuable form of learning for addressing this issue is associative fear conditioning. In this paradigm an animal learns to associate a tone and shock, such that subsequent presentation of a tone evokes a fear response (freezing behavior). Recent studies indicate that overlapping cellular processes underlie fear conditioning and LTP. The fear response has generally been scored manually which is both labor-intensive and subject to potential artifacts such as inconsistent or biased results. Here we describe a simple automated method that provides unbiased and rapid analysis of animal motion. We show that measured motion, in units termed significant motion pixels (SMPs), is both linear and robust over a wide range of animal speeds and detection thresholds and scores freezing in a quantitatively similar manner to trained human observers. By comparing the frequency distribution of motion during baseline periods and to the response to fox urine (which causes unconditioned fear), we suggest that freezing and non-freezing are distinct behaviors. Finally, we show how this algorithm can be applied to a fear conditioning paradigm yielding information on long and short-term associative memory as well as habituation. This automated analysis of fear conditioning will permit a more rapid and accurate assessment of the role of LTP in memory.


Assuntos
Condicionamento Psicológico/fisiologia , Processamento Eletrônico de Dados/métodos , Medo , Potenciação de Longa Duração/fisiologia , Movimento (Física) , Algoritmos , Animais , Comportamento Animal/fisiologia , Camundongos , Valores de Referência , Fatores de Tempo
18.
Psychopharmacology (Berl) ; 194(2): 211-9, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17581743

RESUMO

RATIONALE: There are considerable individual differences in vulnerability to drug addiction, but the mechanisms underlying such differences are poorly understood. Cocaine has potent reinforcing effects that support operant responding. However, cocaine also elicits aversive reactions and produces an approach-avoidance conflict in rats. We hypothesized that preexisting individual differences in open arm exploration on the elevated plus-maze, a well-known model for the study of clinically effective anxiolytic drugs, would predict individual differences in cocaine-motivated behavior. OBJECTIVES: To assess whether individual differences in sensitivity to anxiety-like behavior on the plus-maze predict motivation to self-administer intravenous (i.v.) cocaine. MATERIALS AND METHODS: Rats were assessed drug-free for individual differences in open arm exploration on the elevated plus-maze, and later trained to perform an operant response for i.v. cocaine (0, 0.1, 0.3, 0.6, 0.9, 1.2, and 1.5 mg kg(-1) infusion(-1)) on a progressive-ratio reinforcement schedule. Rats were split at the median into low and high open arm explorers based on time spent in the open arms of the plus-maze. Self-administration levels were compared across groups. RESULTS: Rats identified as high open arm explorers on the elevated plus-maze attained higher levels of operant responding for cocaine. Open arm times and break points were significantly correlated at the highest cocaine doses (1.2 and 1.5 mg kg(-1) infusion(-1)). CONCLUSIONS: These results indicate that individual differences in anxiety-like behavior on the elevated plus-maze predict motivation to self-administer cocaine, and suggest the possibility that reduced sensitivity to aversive stimuli may be associated with increased vulnerability to the rewarding properties of cocaine.


Assuntos
Cocaína/administração & dosagem , Comportamento Exploratório/efeitos dos fármacos , Aprendizagem em Labirinto/efeitos dos fármacos , Animais , Ansiedade/parasitologia , Ansiedade/fisiopatologia , Aprendizagem da Esquiva/efeitos dos fármacos , Aprendizagem da Esquiva/fisiologia , Relação Dose-Resposta a Droga , Comportamento Exploratório/fisiologia , Infusões Intravenosas , Masculino , Aprendizagem em Labirinto/fisiologia , Motivação , Ratos , Ratos Wistar , Esquema de Reforço , Autoadministração , Fatores de Tempo
19.
Phytopathology ; 97(8): 907-15, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18943630

RESUMO

ABSTRACT Pyrenophora teres, the causal agent of net blotch of barley (Hordeum vulgare L.), induces a combination of necrosis and extensive chlorosis in susceptible barley cultivars. Cell-free filtrates from both net and spot forms of P. teres; P. teres f. sp. teres, and P. teres f. sp. maculata were found to contain phytotoxic low molecular weight compounds (LMWCs) and proteinaceous metabolites which appear to be responsible for different components of the symptoms induced by the two forms of the pathogen in a susceptible cultivar of barley (cv. Sloop). Proteins induced only brown necrotic spots or lesions similar to those induced by the pathogens 72 h after inoculation. In contrast, LMWCs induced general chlorosis seen 240 h after inoculation but not the localized necrosis. Neither hydrolyzed or heat- or protease-treated proteinaceous metabolites induced the symptoms. This is the first report of the involvement of proteins produced by P. teres in symptom development during net blotch disease of barley.

20.
Methods Mol Biol ; 1471: 133-145, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28349393

RESUMO

We have built a series of Neurospora crassa strains containing alleles of green fluorescent protein (GFP) to provide a visual phenotype for investigating meiotic recombination. These strains provide a convenient means of screening the Neurospora knockout library for genes involved in genetic recombination. They permit rapid analysis of recombination outcomes by allowing visualization of segregation patterns in a large number of octads from crosses heterozygous for GFP. Using this system the effect of a knockout on gene conversion and/or on crossing over between the fluorescent marker and the centromere can be measured.


Assuntos
Proteínas de Fluorescência Verde/genética , Meiose , Neurospora crassa/genética , Recombinação Genética , Troca Genética , Proteínas Fúngicas/genética , Conversão Gênica , Técnicas de Inativação de Genes/métodos , Heterozigoto , Organismos Geneticamente Modificados
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