RESUMO
PURPOSE: With the rapidly expanding anatomical and technical knowledge surrounding nervesparing radical prostatectomy (NSRP), anatomical and operative textbooks have failed to keep pace with the literature. A surgical skill laboratory (SSL) was designed to educate urology trainees on surgical anatomy and techniques for NSRP. The objective was to assess the validity of a SSL program. METHODS: A low-fidelity, anatomically accurate prostate model with its appropriate fascial coverings and location of the neurovascular bundle was created. Participants were surveyed prior to a SSL workshop for their knowledge of NSRP focusing on clinical and anatomical considerations. An interactive 2-h tutorial and workshop was then undertaken outlining the clinical and anatomical nuances for NSRP, with participants then practising an intra and inter-fascial NSRP on the model. Participants were resurveyed immediately after the workshop and at 6 months. RESULTS: Thirty participants completed the NSRP workshop. Significant differences (p < 0.0001) in anatomical and clinical knowledge were noted after the workshop with improvements for both junior and senior trainees. The knowledge was retained at 6 months following the workshop. CONCLUSIONS: A low-fidelity bench-top model is a feasible and reproducible technique for improving the understanding of periprostatic anatomy and the different surgical approaches for NSRP. The SSL is useful and knowledge gained appears to be retained by workshop participants. SSL workshops are a valid hands-on approach to teaching surgical skills and should remain an integral part of urology training.
Assuntos
Prostatectomia/educação , Neoplasias da Próstata/cirurgia , Urologia/educação , Competência Clínica , Educação , Humanos , Masculino , Tratamentos com Preservação do Órgão , Nervos Periféricos/anatomia & histologia , Próstata/anatomia & histologia , Próstata/cirurgia , Prostatectomia/métodos , Treinamento por SimulaçãoRESUMO
Neurons in the adult mammalian CNS decrease in intrinsic axon growth capacity during development in concert with changes in Krüppel-like transcription factors (KLFs). KLFs regulate axon growth in CNS neurons including retinal ganglion cells (RGCs). Here, we found that knock-down of KLF9, an axon growth suppressor that is normally upregulated 250-fold in RGC development, promotes long-distance optic nerve regeneration in adult rats of both sexes. We identified a novel binding partner, MAPK10/JNK3 kinase, and found that JNK3 (c-Jun N-terminal kinase 3) is critical for KLF9's axon-growth-suppressive activity. Interfering with a JNK3-binding domain or mutating two newly discovered serine phosphorylation acceptor sites, Ser106 and Ser110, effectively abolished KLF9's neurite growth suppression in vitro and promoted axon regeneration in vivo These findings demonstrate a novel, physiologic role for the interaction of KLF9 and JNK3 in regenerative failure in the optic nerve and suggest new therapeutic strategies to promote axon regeneration in the adult CNS.SIGNIFICANCE STATEMENT Injured CNS nerves fail to regenerate spontaneously. Promoting intrinsic axon growth capacity has been a major challenge in the field. Here, we demonstrate that knocking down Krüppel-like transcription factor 9 (KLF9) via shRNA promotes long-distance axon regeneration after optic nerve injury and uncover a novel and important KLF9-JNK3 interaction that contributes to axon growth suppression in vitro and regenerative failure in vivo These studies suggest potential therapeutic approaches to promote axon regeneration in injury and other degenerative diseases in the adult CNS.
Assuntos
Axônios/fisiologia , Encéfalo/fisiologia , Fatores de Transcrição Kruppel-Like/metabolismo , Proteína Quinase 10 Ativada por Mitógeno/metabolismo , Regeneração Nervosa/fisiologia , Fatores Etários , Animais , Sequência de Bases , Células Cultivadas , Sistema Nervoso Central/fisiologia , Feminino , Fatores de Transcrição Kruppel-Like/deficiência , Fatores de Transcrição Kruppel-Like/genética , Masculino , Camundongos , Proteína Quinase 10 Ativada por Mitógeno/genética , Traumatismos do Nervo Óptico/genética , Traumatismos do Nervo Óptico/metabolismo , Técnicas de Cultura de Órgãos , Ligação Proteica/fisiologia , Ratos , Células Ganglionares da Retina/fisiologiaRESUMO
Optic neuropathies such as glaucoma are characterized by the degeneration of retinal ganglion cells (RGCs) and the irreversible loss of vision. In these diseases, focal axon injury triggers a propagating axon degeneration and, eventually, cell death. Previous work by us and others identified dual leucine zipper kinase (DLK) and JUN N-terminal kinase (JNK) as key mediators of somal cell death signaling in RGCs following axonal injury. Moreover, others have shown that activation of the DLK/JNK pathway contributes to distal axonal degeneration in some neuronal subtypes and that this activation is dependent on the adaptor protein, sterile alpha and TIR motif containing 1 (SARM1). Given that SARM1 acts upstream of DLK/JNK signaling in axon degeneration, we tested whether SARM1 plays a similar role in RGC somal apoptosis in response to optic nerve injury. Using the mouse optic nerve crush (ONC) model, our results show that SARM1 is critical for RGC axonal degeneration and that axons rescued by SARM1 deficiency are electrophysiologically active. Genetic deletion of SARM1 did not, however, prevent DLK/JNK pathway activation in RGC somas nor did it prevent or delay RGC cell death. These results highlight the importance of SARM1 in RGC axon degeneration and suggest that somal activation of the DLK/JNK pathway is activated by an as-yet-unidentified SARM1-independent signal.
Assuntos
Proteínas do Domínio Armadillo/fisiologia , Axônios/metabolismo , Proteínas do Citoesqueleto/fisiologia , Modelos Animais de Doenças , Traumatismos do Nervo Óptico/metabolismo , Receptores do Fator de Necrose Tumoral/fisiologia , Degeneração Retiniana/metabolismo , Células Ganglionares da Retina/metabolismo , Animais , Apoptose/fisiologia , Axônios/patologia , Contagem de Células , Sobrevivência Celular , Eletrofisiologia , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Compressão Nervosa , Traumatismos do Nervo Óptico/patologia , Degeneração Retiniana/patologia , Células Ganglionares da Retina/patologiaRESUMO
BACKGROUND: The impact of surgical treatment on outcomes in breast cacner in very young women remains unclear. We sought to determine the effect of surgery type on risk of recurrence and survival in a population-based cohort. METHODS: All women diagnosed with breast cancer aged ≤35 (1994-2003) were identified from the Ontario Cancer Registry. Patient, tumor, and treatment variables, including primary surgery, recurrences, and death were abstracted from chart review. Cox regression models were fit to determine the effect of surgery type on recurrence and overall survival. RESULTS: We identified 1,381 patients with 11-year median follow-up of which 793 (57%) had BCS. Of the remaining mastectomy patients, 52% had postmastectomy radiation. Overall, 41% of patients sustained a recurrence of any type and 31% died. Controlling for known confounders, there was no association between type of surgery and death from any cause (HR = 0.98, 95% CI = 0.78, 1.25) or first recurrence (HR = 0.93, 95% CI = 0.75, 1.14). Distant recurrence was most common (13% in BCS; 25.3% in mastectomy) with local recurrence 12.4% after BCS and 7.5% after mastectomy. CONCLUSIONS: In this cohort of very young women who were selected for treatment with BCS and mastectomy, we found similar oncologic outcomes. J. Surg. Oncol. 2017;115:122-130. © 2017 Wiley Periodicals, Inc.
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Neoplasias da Mama/mortalidade , Carcinoma Ductal de Mama/mortalidade , Carcinoma Lobular/mortalidade , Mastectomia Segmentar/mortalidade , Mastectomia/mortalidade , Recidiva Local de Neoplasia/mortalidade , Adolescente , Adulto , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/cirurgia , Carcinoma Lobular/patologia , Carcinoma Lobular/cirurgia , Feminino , Seguimentos , Humanos , Gradação de Tumores , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Adulto JovemRESUMO
Objective: Access to pregabalin via Ontario's public drug insurance program was expanded to an unrestricted model on April 1, 2013, from a prior authorization model. This study aims to identify the effect of expanded access on the rate of pregabalin use by publicly insured persons and to assess the characteristics of new patients initiating pregabalin following this expanded access. Methods: We conducted a cross-sectional time series analysis using the linked health administrative records of residents of Ontario, Canada, with public drug coverage who were dispensed a prescription for pregabalin between April 1, 2006, and December 31, 2014. Results: A total of 108,047 publicly insured persons were dispensed pregabalin over the study period. The overall rate of pregabalin use increased from 1.0 per 1,000 individuals in Q1 of 2013 to 22.0 per 1,000 individuals in Q4 of 2014. Musculoskeletal (81.6%) and neurological (68.1%) conditions were the most prevalent diagnoses in patients who initiated pregabalin following the expansion of access. Past and concomitant use of opioids, nonsteroidal anti-inflammatory drugs, and antidepressants was also common in this population. Conclusions: Formulary changes in Ontario have led to expanded access to pregabalin, which may have led to an increase in off-label use of these products and potential patient risk associated with concomitant use of pregabalin with central nervous system-depressing drugs.
Assuntos
Analgésicos Opioides/uso terapêutico , Analgésicos/uso terapêutico , Fármacos do Sistema Nervoso Central/uso terapêutico , Uso de Medicamentos/tendências , Seguro de Serviços Farmacêuticos/tendências , Pregabalina/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Uso de Medicamentos/legislação & jurisprudência , Feminino , Humanos , Seguro de Serviços Farmacêuticos/legislação & jurisprudência , Análise de Séries Temporais Interrompida/métodos , Análise de Séries Temporais Interrompida/tendências , Masculino , Pessoa de Meia-Idade , Uso Off-Label/normas , Ontário/epidemiologiaRESUMO
The inner surface of the retina contains a complex mixture of neurons, glia, and vasculature, including retinal ganglion cells (RGCs), the final output neurons of the retina and primary neurons that are damaged in several blinding diseases. The goal of the current work was two-fold: to assess the feasibility of using computer-assisted detection of nuclei and random forest classification to automate the quantification of RGCs in hematoxylin/eosin (H&E)-stained retinal whole-mounts; and if possible, to use the approach to examine how nuclear size influences disease susceptibility among RGC populations. To achieve this, data from RetFM-J, a semi-automated ImageJ-based module that detects, counts, and collects quantitative data on nuclei of H&E-stained whole-mounted retinas, were used in conjunction with a manually curated set of images to train a random forest classifier. To test performance, computer-derived outputs were compared to previously published features of several well-characterized mouse models of ophthalmic disease and their controls: normal C57BL/6J mice; Jun-sufficient and Jun-deficient mice subjected to controlled optic nerve crush (CONC); and DBA/2J mice with naturally occurring glaucoma. The result of these efforts was development of RetFM-Class, a command-line-based tool that uses data output from RetFM-J to perform random forest classification of cell type. Comparative testing revealed that manual and automated classifications by RetFM-Class correlated well, with 83.2% classification accuracy for RGCs. Automated characterization of C57BL/6J retinas predicted 54,642 RGCs per normal retina, and identified a 48.3% Jun-dependent loss of cells at 35 days post CONC and a 71.2% loss of RGCs among 16-month-old DBA/2J mice with glaucoma. Output from automated analyses was used to compare nuclear area among large numbers of RGCs from DBA/2J mice (n = 127,361). In aged DBA/2J mice with glaucoma, RetFM-Class detected a decrease in median and mean nucleus size of cells classified into the RGC category, as did an independent confirmation study using manual measurements of nuclear area demarcated by BRN3A-immunoreactivity. In conclusion, we have demonstrated that histology-based random forest classification is feasible and can be utilized to study RGCs in a high-throughput fashion. Despite having some limitations, this approach demonstrated a significant association between the size of the RGC nucleus and the DBA/2J form of glaucoma.
Assuntos
Contagem de Células/métodos , Técnicas de Diagnóstico Oftalmológico , Glaucoma/classificação , Células Ganglionares da Retina/citologia , Células Amácrinas , Animais , Núcleo Celular/patologia , Diagnóstico por Computador/métodos , Modelos Animais de Doenças , Estudos de Viabilidade , Glaucoma/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBARESUMO
BACKGROUND: Comprehensive systems for surveilling prescription opioid-related harms provide clear evidence that deaths from prescription opioids have increased dramatically in the United States. However, these harms are not systematically monitored in Canada. In light of a growing public health crisis, accessible, nationwide data sources to examine prescription opioid-related harms in Canada are needed. We sought to examine the performance of 5 algorithms to identify prescription opioid-related deaths from vital statistics data against data abstracted from the Office of the Chief Coroner of Ontario as a gold standard. METHODS: We identified all prescription opioid-related deaths from Ontario coroners' data that occurred between Jan. 31, 2003, and Dec. 31, 2010. We then used 5 different algorithms to identify prescription opioid-related deaths from vital statistics death data in 2010. We selected the algorithm with the highest sensitivity and a positive predictive value of more than 80% as the optimal algorithm for identifying prescription opioid-related deaths. RESULTS: Four of the 5 algorithms had positive predictive values of more than 80%. The algorithm with the highest sensitivity (75%) in 2010 improved slightly in its predictive performance from 2003 to 2010. INTERPRETATION: In the absence of specific systems for monitoring prescription opioid-related deaths in Canada, readily available national vital statistics data can be used to study prescription opioid-related mortality with considerable accuracy. Despite some limitations, these data may facilitate the implementation of national surveillance and monitoring strategies.
Assuntos
Analgésicos Opioides/efeitos adversos , Overdose de Drogas/mortalidade , Prescrições de Medicamentos/estatística & dados numéricos , Algoritmos , Analgésicos Opioides/uso terapêutico , Canadá/epidemiologia , Humanos , Ontário/epidemiologia , Sensibilidade e Especificidade , Estatísticas VitaisRESUMO
Cigarette smoke has a broad impact on the mucosal environment with the ability to alter host defense mechanisms. Within the context of a bacterial infection, this altered host response is often accompanied by exacerbated cellular inflammation, characterized by increased neutrophilia. The current study investigated the mechanisms of neutrophil recruitment in a murine model of cigarette smoke exposure and, subsequently, a model of both cigarette smoke exposure and bacterial infection. We investigated the role of IL-1 signaling in neutrophil recruitment and found that cigarette smoke-induced neutrophilia was dependent on IL-1α produced by alveolar macrophages. In addition to being the crucial source of IL-1α, alveolar macrophages isolated from smoke-exposed mice were primed for excessive IL-1α production in response to bacterial ligands. To test the relevance of exaggerated IL-1α production in neutrophil recruitment, a model of cigarette smoke exposure and nontypeable Haemophilus influenzae infection was developed. Mice exposed to cigarette smoke elaborated an exacerbated CXCR2-dependent neutrophilia in response to nontypeable Haemophilus influenzae. Exacerbated neutrophilia was dependent on IL-1α priming of the pulmonary environment by cigarette smoke as exaggerated neutrophilia was dependent on IL-1 signaling. These data characterize a novel mechanism of cigarette smoke priming the lung mucosa toward greater IL-1-driven neutrophilic responses to bacteria, with a central role for the alveolar macrophage in this process.
Assuntos
Haemophilus influenzae/imunologia , Interleucina-1alfa/imunologia , Infiltração de Neutrófilos/imunologia , Neutrófilos/imunologia , Receptores de Interleucina-8B/imunologia , Fumaça/efeitos adversos , Animais , Líquido da Lavagem Broncoalveolar/citologia , Células Cultivadas , Quimiocina CXCL1/biossíntese , Quimiocina CXCL5/biossíntese , Quimiocina CXCL5/genética , Quimiocina CXCL5/imunologia , Feminino , Infecções por Haemophilus/imunologia , Infecções por Haemophilus/microbiologia , Inflamação/imunologia , Contagem de Leucócitos , Pulmão/patologia , Macrófagos Alveolares/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Doença Pulmonar Obstrutiva Crônica/imunologia , Doença Pulmonar Obstrutiva Crônica/patologia , RNA Mensageiro/biossíntese , Receptores de Interleucina-8B/biossíntese , Receptores de Interleucina-8B/genética , Mucosa Respiratória/imunologia , Mucosa Respiratória/microbiologia , Nicotiana/efeitos adversosRESUMO
While all forms of glaucoma are characterized by a specific pattern of retinal ganglion cell death, they are clinically divided into several distinct subclasses, including normal tension glaucoma, primary open angle glaucoma, congenital glaucoma, and secondary glaucoma. For each type of glaucoma there are likely numerous molecular pathways that control susceptibility to the disease. Given this complexity, a single animal model will never precisely model all aspects of all the different types of human glaucoma. Therefore, multiple animal models have been utilized to study glaucoma but more are needed. Because of the powerful genetic tools available to use in the laboratory mouse, it has proven to be a highly useful mammalian system for studying the pathophysiology of human disease. The similarity between human and mouse eyes coupled with the ability to use a combination of advanced cell biological and genetic tools in mice have led to a large increase in the number of studies using mice to model specific glaucoma phenotypes. Over the last decade, numerous new mouse models and genetic tools have emerged, providing important insight into the cell biology and genetics of glaucoma. In this review, we describe available mouse genetic models that can be used to study glaucoma-relevant disease/pathobiology. Furthermore, we discuss how these models have been used to gain insights into ocular hypertension (a major risk factor for glaucoma) and glaucomatous retinal ganglion cell death. Finally, the potential for developing new mouse models and using advanced genetic tools and resources for studying glaucoma are discussed.
Assuntos
Glaucoma/genética , Pressão Intraocular , Animais , Modelos Animais de Doenças , Humanos , Camundongos , Células Ganglionares da Retina/metabolismo , Células Ganglionares da Retina/patologiaRESUMO
AIMS: Clopidogrel and angiotensin converting enzyme (ACE) inhibitors are commonly co-prescribed drugs. Clopidogrel inhibits carboxylesterase 1 (CES1), the enzyme responsible for converting prodrug ACE inhibitors (such as ramipril and perindopril) to their active metabolites. The clinical implications of this potential drug interaction are unknown. The clinical consequences of the potential drug interaction between clopidogrel and prodrug ACE inhibitors were examined. METHODS: We conducted a nested case-control study of Ontarians aged 66 years and older treated with clopidogrel between September 1 2003 and March 31 2013 following acute myocardial infarction. Cases were subjects who died or were hospitalized for reinfarction or heart failure in the subsequent year, and each was matched with up to four controls. The primary outcome was a composite of reinfarction, heart failure or death. The primary analysis examined whether use of the prodrug ACE inhibitors ramipril or perindopril was more common among cases than use of lisinopril, an active ACE inhibitor. RESULTS: Among 45 918 patients treated with clopidogrel following myocardial infarction, we identified 4203 cases and 14 964 controls. After adjustment, we found no association between the composite outcome and use of perindopril (adjusted odds ratio (aOR) 0.94, 95% confidence interval (CI) 0.76, 1.16) or ramipril (aOR 0.97, 95% CI 0.80, 1.18), relative to lisinopril. Secondary analyses of each element of the composite outcome yielded similar findings. CONCLUSIONS: Following myocardial infarction, use of clopidogrel with ACE inhibitors activated by CES1 is not associated with an increased risk of adverse cardiovascular outcomes relative to lisinopril. These findings suggest that the recently described drug interaction between clopidogrel and prodrug ACE inhibitors is of little clinical relevance.
Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Lisinopril/farmacologia , Perindopril/farmacologia , Ramipril/farmacologia , Ticlopidina/análogos & derivados , Idoso , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Estudos de Casos e Controles , Clopidogrel , Bases de Dados Factuais , Interações Medicamentosas , Quimioterapia Combinada , Feminino , Insuficiência Cardíaca , Humanos , Lisinopril/uso terapêutico , Masculino , Infarto do Miocárdio/tratamento farmacológico , Perindopril/uso terapêutico , Inibidores da Agregação Plaquetária/farmacologia , Ramipril/uso terapêutico , Recidiva , Ticlopidina/farmacologia , Ticlopidina/uso terapêutico , Resultado do TratamentoRESUMO
PURPOSE: Ticagrelor increases serum adenosine concentrations, slowing conduction and possibly leading to bradycardia. Clinical trial data have shown numerically, though not statistically significantly, higher rates of bradyarrhythmias with ticagrelor versus clopidogrel. Additionally, recent case reports have further raised concerns for this adverse effect. We explored the association between ticagrelor and hospitalization for bradycardia in a real-world setting. METHODS: We conducted a population-based, nested case-control study of Ontario residents, 66 years of age or older, discharged after a first acute coronary syndrome by linking multiple healthcare databases. Cases included patients hospitalized for bradycardia within 1 year of starting a P2Y12 inhibitor. For each case, we identified 4 controls matched on age, sex, index date, and current use of a P2Y12 inhibitor. The exposure of interest was a prescription for ticagrelor within 90 days, with clopidogrel use as the reference group. RESULTS: From April 2012 to March 2014, we identified 140 cases and 560 controls who met the study criteria. We found no significant association between bradycardia and exposure to ticagrelor relative to clopidogrel in the previous 90 days prior to the index date (adjusted odds ratio 1.06, 95% confidence interval 0.65-2.21). Further adjustment for potential confounders also did not identify a significant association. CONCLUSIONS: Among older patients with a first acute coronary syndrome, use of ticagrelor was not associated with a greater risk of admission for bradycardia relative to clopidogrel.
Assuntos
Adenosina/análogos & derivados , Bradicardia/epidemiologia , Antagonistas do Receptor Purinérgico P2Y/efeitos adversos , Adenosina/efeitos adversos , Sistemas de Notificação de Reações Adversas a Medicamentos , Idoso , Idoso de 80 Anos ou mais , Bradicardia/induzido quimicamente , Estudos de Casos e Controles , Feminino , Serviços de Saúde para Idosos , Hospitalização , Humanos , Masculino , Ontário/epidemiologia , TicagrelorRESUMO
BACKGROUND: Utilization of breast reconstruction (BR) is low in many jurisdictions. We studied the geographical and surgical workforce factors that contribute to access and use of BR using a small area analysis approach with a geographical unit of analysis. METHODS: We linked administrative data from Ontario Canada to calculate the age-standardized rates for immediate BR (IBR) (same time as mastectomy) between 2002 and 2011, and delayed BR (DBR) (within 3 years of mastectomy) for each county. The influence of plastic surgeon access on variation in county rates of BR was examined using Poisson random effects models. RESULTS: 12,663 women underwent mastectomy in Ontario; 2,948 had BR within 3 years (23.3%). Over 50% of the counties had no access to any plastic surgeon. County IBR rates ranged from 0 to 21.5%; plastic surgeon access explained 46% of geographic variation (p<0.0001). IBR rates in counties with very low, low, and moderate access to plastic surgeons were significantly less than counties with high access (relative rate [RR] 0.48 [95% confidence interval (CI) 0.35-0.66], RR 0.61 [CI 0.43-0.87] and RR 0.70 [CI 0.52-0.96], respectively) after adjusting for age and county socioeconomic characteristics. For DBR, while there was less geographic variation, very low access counties demonstrated reduced rates (RR 0.60 [CI 0.47-0.76]). INTERPRETATION: Geographic access to a plastic surgeon is a major determinant of BR. Targeted interventions for regions without high access to plastic surgeons may improve overall rates and reduce geographic disparities in care, particularly for IBR.
Assuntos
Acessibilidade aos Serviços de Saúde , Mamoplastia/estatística & dados numéricos , Cirurgiões/provisão & distribuição , Adolescente , Adulto , Idoso , Neoplasias da Mama/cirurgia , Feminino , Humanos , Mastectomia/estatística & dados numéricos , Pessoa de Meia-Idade , Ontário/epidemiologia , Adulto JovemRESUMO
Injury to retinal ganglion cell (RGC) axons triggers rapid activation of Jun N-terminal kinase (JNK) signaling, a major prodeath pathway in injured RGCs. Of the multiple kinases that can activate JNK, dual leucine kinase (Dlk) is known to regulate both apoptosis and Wallerian degeneration triggered by axonal insult. Here we tested the importance of Dlk in regulating somal and axonal degeneration of RGCs following axonal injury. Removal of DLK from the developing optic cup did not grossly affect developmental RGC death or inner plexiform layer organization. In the adult, Dlk deficiency significantly delayed axonal-injury induced RGC death. The activation of JUN was also attenuated in Dlk deficient retinas. Dlk deficiency attenuated the activation of the somal pool of JNK but did not prevent activation of the axonal pool of JNK after axonal injury, indicating that JNK activation in different cellular compartments of an RGC following axonal injury is regulated by distinct upstream kinases. In contrast to its robust influence on somal degeneration, Dlk deficiency did not alter RGC axonal degeneration after axonal injury as assessed using physiological readouts of optic nerve function.
Assuntos
Axônios/enzimologia , MAP Quinase Quinase Quinases/deficiência , Traumatismos do Nervo Óptico/enzimologia , Células Ganglionares da Retina/enzimologia , Degeneração Walleriana/enzimologia , Animais , Axônios/patologia , Morte Celular/fisiologia , Sobrevivência Celular/fisiologia , Modelos Animais de Doenças , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , MAP Quinase Quinase Quinases/genética , Camundongos Transgênicos , Traumatismos do Nervo Óptico/patologia , Fosforilação/fisiologia , Retina/enzimologia , Retina/crescimento & desenvolvimento , Retina/patologia , Células Ganglionares da Retina/patologia , Transdução de Sinais , Técnicas de Cultura de Tecidos , Degeneração Walleriana/patologiaRESUMO
BACKGROUND: Glaucoma is an optic neuropathy that is characterized by the loss of retinal ganglion cells (RGCs) initiated by damage to axons in the optic nerve. The degeneration and death of RGCs has been thought to occur in two waves. The first is axogenic, caused by direct insult to the axon. The second is somatic, and is thought to be caused by the production of inflammatory cytokines from the activated retinal innate immune cells. One of the cytokines consistently linked to glaucoma and RGC damage has been TNFα. Despite strong evidence implicating this protein in neurodegeneration, a direct injection of TNFα does not mimic the rapid loss of RGCs observed after acute optic nerve trauma or exposure to excitotoxins. This suggests that our understanding of TNFα signaling is incomplete. METHODS: RGC death was induced by optic nerve crush in mice. The role of TNFα in this process was examined by quantitative PCR of Tnfα gene expression, and quantification of cell loss in Tnfα (-/-) mice or in wild-type animals receiving an intraocular injection of exongenous TNFα either before or after crush. Signaling pathways downstream of TNFα were examined by immunolabeling for JUN protein accumulation or activation of EGFP expression in NFκB reporter mice. RESULTS: Optic nerve crush caused a modest increase in Tnfα gene expression, with kinetics similar to the activation of both macroglia and microglia. A pre-injection of TNFα attenuated ganglion cell loss after crush, while ganglion cell loss was more severe in Tnfα (-/-) mice. Conversely, over the long term, a single exposure to TNFα induced extrinsic apoptosis in RGCs. Müller cells responded to exogenous TNFα by accumulating JUN and activating NFκB. CONCLUSION: Early after optic nerve crush, TNFα appears to have a protective role for RGCs, which may be mediated through Müller cells.
Assuntos
Compressão Nervosa , Fármacos Neuroprotetores/uso terapêutico , Traumatismos do Nervo Óptico/tratamento farmacológico , Traumatismos do Nervo Óptico/patologia , Células Ganglionares da Retina/patologia , Fator de Necrose Tumoral alfa/uso terapêutico , Animais , Relação Dose-Resposta a Droga , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fármacos Neuroprotetores/metabolismo , Fármacos Neuroprotetores/farmacologia , Traumatismos do Nervo Óptico/metabolismo , Células Ganglionares da Retina/efeitos dos fármacos , Células Ganglionares da Retina/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
BACKGROUND: We describe trends in participation by investigators from low- and middle-income countries (LMCs) in publications describing oncology randomized control trials (RCTs) over a decade. METHODS: We used Medline to identify RCTs published in English from 1998 to 2008 evaluating treatment in lung, breast, colorectal, stomach and liver cancers. Data on author affiliations, authorship roles, trial characteristics, funding and interventions were extracted from each article. Countries were stratified as low-, middle- or high-income using World Bank data. Interventions were categorized as requiring basic, limited, enhanced or maximal resources as per the Breast Health Global Initiative classification. Logistic regression was used to identify factors associated with authorship by investigators from LMCs. RESULTS: 454 publications were identified. Proportion of articles with at least one LMC author increased over time from 20% in 1998 to 29% in 2008 (p = 0.01), but almost all LMC authors were from middle-income countries. Proportion of articles with at least one LMC author was higher among articles that explicitly reported recruitment in at least one LMC vs those that did not (76% vs 13%). Among 87 articles (19%) that involved authors from LMCs, 17% had LMC authors as first or corresponding authors, and 67% evaluated interventions requiring enhanced or maximal resources. Factors associated with LMC authorship included industry funding (OR = 3.54, p = 0.0001), placebo comparator arm (OR = 2.57, p = 0.02) and palliative intent treatment (OR = 4.00, p = 0.0003). CONCLUSION: An increasing number of publications describing oncology RCTs involve authors from LMC countries but primarily in non-leadership roles in industry-funded trials.
Assuntos
Bibliometria , Países em Desenvolvimento , Neoplasias/terapia , Publicações Periódicas como Assunto/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , HumanosRESUMO
The AP1 family transcription factor JUN is an important molecule in the neuronal response to injury. In retinal ganglion cells (RGCs), JUN is upregulated soon after axonal injury and disrupting JUN activity delays RGC death. JUN is known to participate in the control of many different injury response pathways in neurons, including pathways controlling cell death and axonal regeneration. The role of JUN in regulating genes involved in cell death, ER stress, and regeneration was tested to determine the overall importance of JUN in regulating RGC response to axonal injury. Genes from each of these pathways were transcriptionally controlled following axonal injury and Jun deficiency altered the expression of many of these genes. The differentially expressed genes included, Atf3, Ddit3, Ecel1, Gadd45α, Gal, Hrk, Pten, Socs3, and Sprr1a. Two of these genes, Hrk and Atf3, were tested for importance in RGC death using null alleles of each gene. Disruption of the prodeath Bcl2 family member Hrk did not affect the rate or amount of RGC death after axonal trauma. Deficiency in the ATF/CREB family transcription factor Atf3 did lessen the amount of RGC death after injury, though it did not provide long term protection to RGCs. Since JUN's dimerization partner determines its transcriptional targets, the expression of several candidate AP1 family members were examined. Multiple AP1 family members were induced by axonal injury and had a different expression profile in Jun deficient retinas compared to wildtype retinas (Fosl1, Fosl2 and Jund). Overall, JUN appears to play a multifaceted role in regulating RGC response to axonal injury.
Assuntos
Apoptose , Axônios/patologia , Regeneração Nervosa/fisiologia , Traumatismos do Nervo Óptico/genética , Proteínas Proto-Oncogênicas c-jun/fisiologia , Células Ganglionares da Retina/patologia , Fator de Transcrição AP-1/genética , Fator 3 Ativador da Transcrição/genética , Fator 3 Ativador da Transcrição/metabolismo , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Contagem de Células , Sobrevivência Celular , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Compressão Nervosa , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Traumatismos do Nervo Óptico/metabolismo , Traumatismos do Nervo Óptico/fisiopatologia , Reação em Cadeia da Polimerase em Tempo Real , Ativação TranscricionalRESUMO
OBJECTIVE: To evaluate the patterns of radiologic imaging requested by family physicians and gynaecologists in the work-up of women found to have an adnexal mass on pelvic ultrasound, and to evaluate whether advanced imaging tests are associated with more appropriate referral of women with a high-risk adnexal mass to gynaecologic oncologists. METHODS: Centralized provincial databases of health care usage were used to identify women aged 45 and older who had a pelvic ultrasound examination between 2006 and 2008. Subsequent imaging tests ordered were identified according to physician specialty. For women who proceeded to laparotomy, logistic regression was performed to determine which imaging tests enabled primary physicians to make appropriate referrals of women with high risk adnexal tumours to a gynaecologic oncologist. RESULTS: We identified 193 261 women aged 45 and older who had a pelvic ultrasound. Of these, 19 949 (10.3%) had a subsequent laparotomy; 2223 women were categorized as having a benign adnexal mass, 627 were categorized as having a malignant adnexal mass, and the remainder had another diagnosis such as uterine fibroid. Up to 12% of women had a pelvic MRI, and 58% of women had a CT scan after a pelvic ultrasound. Family physicians referred 95% of women with a high-risk ovarian mass to a gynaecologic surgeon rather than to a gynaecologic oncologist, and gynaecologists referred 47% of such women to a gynaecologic oncologist after imaging. Gynaecologic oncologists operated on 55% of women with a malignant adnexal mass. On multivariate analysis, a preoperative CT scan (OR 3.58; P < 0.001) and a CT scan and MRI (OR 7.78; P < 0.001) were associated with surgery performed by a gynaecologic oncologist, but a preoperative MRI alone was not significantly associated (OR 1.86; P = 0.09). After ultrasound alone the mean time to surgery was 100 days; this increased significantly when further imaging tests were performed (with additional CT to 131 days, with MRI to 170 days, and with CT and MRI to 179 days; P = 0.002). CONCLUSION: Performing a pelvic MRI after a pelvic ultrasound does not increase the rate of referral of women with a high-risk adnexal mass to a gynaecologic oncologist. A consensus on appropriate imaging and triage is needed when an adnexal mass is identified on ultrasound.
Assuntos
Imageamento por Ressonância Magnética/estatística & dados numéricos , Neoplasias Ovarianas/diagnóstico por imagem , Padrões de Prática Médica/estatística & dados numéricos , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Idoso , Feminino , Ginecologia/estatística & dados numéricos , Humanos , Oncologia/estatística & dados numéricos , Pessoa de Meia-Idade , Ontário , Neoplasias Ovarianas/cirurgia , Encaminhamento e Consulta/estatística & dados numéricos , Fatores de Tempo , UltrassonografiaRESUMO
The Bcl-2 family is responsible for regulating cell death pathways in neurons during development, after injury and in disease. The activation of the pro-death family member BAX is often the final step before cell death in neurons. Pro-survival family members such as BCL-X (BCL2L1) act to inhibit BAX activation. Overexpression studies have suggested that BCL-X could play an important physiological role in mediating neuronal viability. Loss-of-function studies performed in vivo have implicated BCL-X as a mediator of neuronal survival during the early stages of neurodevelopment. To assess whether BCL-X is needed to promote the survival of neurons in the central nervous system throughout life, Bcl-x was conditionally removed from the optic cup or throughout the adult mouse. During development BCL-X was required for the survival of differentiating retinal ganglion cells (RGCs) leading up to their normal window of developmental death. Despite its expression in adult RGCs, BCL-X was not required for maintaining RGC viability in adult retinas. However, the loss of BCL-X in adult RGCs did significantly increase the rate of death of RGCs after axonal injury. Thus, in developing and injured RGCs there appears to be an active cell survival program preventing neuronal death.
Assuntos
Células Ganglionares da Retina/fisiologia , Proteína bcl-X/fisiologia , Animais , Apoptose/genética , Sobrevivência Celular/genética , Regulação da Expressão Gênica , Camundongos , Neurogênese/genética , Células Ganglionares da Retina/metabolismo , Proteína bcl-X/genéticaRESUMO
Glaucoma is a neurodegenerative disease characterized by the apoptotic death of retinal ganglion cells (RGCs). The primary insult to RGCs in glaucoma is thought to occur to their axons as they exit the eye in the optic nerve head. However, pathological signaling pathways that exert central roles in triggering RGC death following axonal injury remain unidentified. It is likely that the first changes to occur following axonal injury are signal relay events that transduce the injury signal from the axon to the cell body. Here we focus on the c-Jun N-terminal kinase (JNK1-3) family, a signaling pathway implicated in axonal injury signaling and neurodegenerative apoptosis, and likely to function as a central node in axonal injury-induced RGC death. We show that JNK signaling is activated immediately after axonal injury in RGC axons at the site of injury. Following its early activation, sustained JNK signaling is observed in axonally-injured RGCs in the form of JUN phosphorylation and upregulation. Using mice lacking specific Jnk isoforms, we show that Jnk2 and Jnk3 are the isoforms activated in injured axons. Combined deficiency of Jnk2 and Jnk3 provides robust long-term protection against axonal injury-induced RGC death and prevents downregulation of the RGC marker, BRN3B, and phosphorylation of JUN. Finally, using Jun deficient mice, we show that JUN-dependent pathways are important for axonal injury-induced RGC death. Together these data demonstrate that JNK signaling is the major early pathway triggering RGC death after axonal injury and may directly link axon injury to transcriptional activity that controls RGC death.
Assuntos
Axônios/enzimologia , Sistema de Sinalização das MAP Quinases/fisiologia , Proteína Quinase 10 Ativada por Mitógeno/fisiologia , Proteína Quinase 9 Ativada por Mitógeno/fisiologia , Células Ganglionares da Retina/enzimologia , Animais , Axônios/patologia , Morte Celular , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Knockout , Traumatismos do Nervo Óptico/enzimologia , Traumatismos do Nervo Óptico/genética , Traumatismos do Nervo Óptico/patologia , Células Ganglionares da Retina/patologia , Ativação Transcricional/fisiologiaRESUMO
UNLABELLED: Study Type - Prognosis (cohort) Level of Evidence 2b. What's known on the subject? and What does the study add? ADIPOSE tissue secretes various endocrine and paracrine mediators. Some authors have begun to consider whether peri-prostatic fat (PPF) may interact with the prostate and play a role in carcinogenesis. It has recently been shown that the PPF quantity measured by CT is associated with more aggressive disease in patients undergoing radiation therapy. Our group studied a population not yet diagnosed with prostate cancer. By doing so we were able to identify PPF thickness on transrectal ultrasonography as a risk factor for prostate cancer detection upon biopsy, and as a risk factor for high-grade disease. Our study also raises interesting questions about the underlying mechanisms of the association between PPF quantity and prostate cancer. OBJECTIVE: To determine if the amount of peri-prostatic fat (PPF) on transrectal ultrasonography (TRUS) is a risk factor for incident prostate cancer overall and high-grade prostate cancer (Gleason ≥4). PATIENTS AND METHODS: A prospectively maintained database of patients undergoing prostate biopsy at Princess Margaret Hospital for cancer suspicion was used. ⢠All TRUS examinations were retrospectively reviewed upon 'blinding' to outcome. ⢠PPF thickness, measured as the distance between the prostate and the pubic bone, was used as an index of the quantity of PPF. ⢠PPF measurements, together with other prostate cancer risk factors, were evaluated against prostate cancer and high-grade prostate cancer detection upon biopsy with univariable and multivariable logistic regression and area under the receiver operating characteristic curve (AUC) analysis. RESULTS: Of the 931 patients, 434 (47%) were diagnosed with prostate cancer and 218 (23%) were diagnosed with high-grade prostate cancer. ⢠The mean (range) PPF thickness was 5.3 (0-15) mm. ⢠Increasing PPF thickness was associated with prostate cancer and high-grade prostate cancer diagnosis, with graded effect. When adjusting for other variables, the odds of detecting any prostate cancer and high-grade prostate cancer increased 12% (odds ratio [OR] 1.12, 95% confidence interval [CI] 1.02-1.23) and 20% (OR 1.20, 95% CI 1.07-1.34), respectively, for each millimetre increase in PPF thickness. ⢠The AUCs for the association of PPF with prostate cancer and high-grade prostate cancer were 0.58 (95% CI 0.54-0.62) and 0.59 (95% CI 0.55-0.64), respectively. CONCLUSION: The amount of PPF can be estimated with TRUS and is a predictor of prostate cancer and high-grade prostate cancer at biopsy. To our knowledge, this study is the first to investigate PPF quantity in patients without prior prostate cancer diagnosis.