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1.
J Neurosci ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38942470

RESUMO

NMDA-type glutamate receptors (NMDARs) are widely recognized as master regulators of synaptic plasticity, most notably for driving long-term changes in synapse size and strength that support learning. NMDARs are unique among neurotransmitter receptors in that they require binding of both neurotransmitter (glutamate) and co-agonist (e.g. d-serine) to open the receptor channel, which leads to the influx of calcium ions that drive synaptic plasticity. Over the past decade, evidence has accumulated that NMDARs also support synaptic plasticity via ion flux-independent (non-ionotropic) signaling upon the binding of glutamate in the absence of co-agonist, although conflicting results have led to significant controversy. Here, we hypothesized that a major source of contradictory results can be attributed to variable occupancy of the co-agonist binding site under different experimental conditions. To test this hypothesis, we manipulated co-agonist availability in acute hippocampal slices from mice of both sexes. We found that enzymatic scavenging of endogenous co-agonists enhanced the magnitude of LTD induced by non-ionotropic NMDAR signaling in the presence of the NMDAR pore blocker, MK801. Conversely, a saturating concentration of d-serine completely inhibited both LTD and spine shrinkage induced by glutamate binding in the presence of MK801. Using a FRET-based assay in cultured neurons, we further found that d-serine completely blocked NMDA-induced conformational movements of the GluN1 cytoplasmic domains in the presence of MK801. Our results support a model in which d-serine inhibits ion flux-independent NMDAR signaling and plasticity, and thus d-serine availability could serve to modulate NMDAR signaling even when the NMDAR is blocked by magnesium.Significance Statement NMDARs are glutamate-gated cation channels that are key regulators of neurodevelopment and synaptic plasticity and unique in their requirement for binding of a co-agonist (e.g. d-serine) in order for the channel to open. NMDARs have been found to drive synaptic plasticity via non-ionotropic (ion flux-independent) signaling upon the binding of glutamate in the absence of co-agonist, though conflicting results have led to controversy. Here, we found that d-serine inhibits non-ionotropic NMDAR-mediated LTD and LTD-associated spine shrinkage. Thus, a major source of the contradictory findings might be attributed to experimental variability in d-serine availability. In addition, the developmental regulation of d-serine levels suggests a role for non-ionotropic NMDAR plasticity during critical periods of plasticity.

2.
Neurobiol Dis ; 170: 105772, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35605760

RESUMO

Schizophrenia is a psychiatric disorder that affects over 20 million people globally. Notably, schizophrenia is associated with decreased density of dendritic spines and decreased levels of d-serine, a co-agonist required for opening of the N-methyl-d-aspartate receptor (NMDAR). We hypothesized that lowered d-serine levels associated with schizophrenia would enhance ion flux-independent signaling by the NMDAR, driving destabilization and loss of dendritic spines. We tested our hypothesis using the serine racemase knockout (SRKO) mouse model, which lacks the enzyme for d-serine production. We show that activity-dependent spine growth is impaired in SRKO mice, but can be acutely rescued by exogenous d-serine. Moreover, we find a significant bias of synaptic plasticity toward spine shrinkage in the SRKO mice as compared to wild-type littermates. Notably, we demonstrate that enhanced ion flux-independent signaling through the NMDAR contributes to this bias toward spine destabilization, which is exacerbated by an increase in synaptic NMDARs in hippocampal synapses of SRKO mice. Our results support a model in which lowered d-serine levels associated with schizophrenia enhance ion flux-independent NMDAR signaling and bias toward spine shrinkage and destabilization.


Assuntos
Receptores de N-Metil-D-Aspartato , Esquizofrenia , Animais , Espinhas Dendríticas , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Knockout , Plasticidade Neuronal , Serina
3.
J Neurooncol ; 158(3): 341-348, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35486307

RESUMO

PURPOSE: We sought to evaluate the effects of concurrent temozolomide-based chemoradiation therapy on neurocognitive function in patients with low-grade glioma (LGG). MATERIALS/METHODS: We included adult patients with LGG who were treated postoperatively with radiotherapy (RT) with concurrent and adjuvant temozolomide (TMZ). Patients were evaluated with comprehensive psychometric tests at baseline (prior to RT + TMZ) and at various time intervals following RT + TMZ. Baseline cognitive performance was analyzed by sex, age, education history, history of seizures, IDH mutation status, and 1p/19q codeletion status. Changes in neurocognitive performance were evaluated over time. RESULTS: Thirty-seven LGG patients (mean age 43.6, 59.5% male) had baseline neurocognitive evaluation. Patients with an age > 40 years old at diagnosis and those with an education > 16 years demonstrated superior baseline verbal memory as assessed by HVLT. No other cognitive domains showed differences when stratified by the variables mentioned above. A total of 22 LGG patients had baseline and post RT + TMZ neurocognitive evaluation. Overall, patients showed no statistical difference between group mean test scores prior to and following RT + TMZ on all psychometric measures (with the exception of HVLT Discrimination). CONCLUSION: Cognitive function remained stable following RT + TMZ in LGG patients evaluated prospectively up to 2 years. The anticipated analysis of RTOG 0424 will provide valuable neurocognitive outcomes specifically for high risk LGG patients treated with RT + TMZ.


Assuntos
Neoplasias Encefálicas , Glioma , Adulto , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/genética , Cognição , Feminino , Glioma/genética , Humanos , Masculino , Temozolomida/uso terapêutico
4.
J Neurooncol ; 156(3): 499-507, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35064450

RESUMO

PURPOSE: Low-grade glioma (LGG) exhibits longer median survival than high-grade brain tumors, and thus impact of our therapies on patient quality of life remains a crucial consideration. This study evaluated the effects of concurrent temozolomide-based chemoradiation (RT + TMZ) or observation on quality of life (QOL) in patients with low-grade glioma. METHODS: We completed a retrospective cross-sectional study of adults with LGG who underwent surgery with known molecular classification from 1980 to 2018. Postoperatively, patients were either observed or received adjuvant concurrent temozolomide-based chemoradiation. EQ-5D and PHQ-9 depression screen were completed before outpatient visits every 2-3 months. Baseline score was defined as ± 30 days within initial operation. RESULTS: Of the 63 patients (mean age 44 ± 17 years, 51% female) with baseline EQ-5D or PHQ-9 depression screen data and at least one follow-up measure, 30 (48%) were observed and 33 (52%) received RT + TMZ. No significant decline was seen in EQ-5D or PHQ-9 scores at 3, 6, 9, 12, and 24 months compared to baseline scores for all patients. At each time point, there was no significant difference between those who were observed or received adjuvant therapy. The linear mixed model estimating PHQ-9 value or EQ-5D index demonstrated that there was no significant difference in PHQ-9 or EQ-5D index between treatment groups (p = 0.42 and p = 0.54, respectively) or time points (p = 0.24 and p = 0.99, respectively). CONCLUSION: Our study found no significant decline in patient QOL or depression scores as assessed by patient- reported outcome measures for patients with low-grade glioma up to 2 years following surgery. We found no difference between RT + TMZ compared to observation during this time frame. Additional follow-up can help identify the longer-term impact of treatment strategy on patient experience.


Assuntos
Neoplasias Encefálicas , Quimiorradioterapia , Glioma , Qualidade de Vida , Temozolomida , Conduta Expectante , Adulto , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Estudos Transversais , Feminino , Glioma/patologia , Glioma/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estudos Retrospectivos , Temozolomida/uso terapêutico , Resultado do Tratamento
5.
J Neurosci ; 40(19): 3741-3750, 2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32321746

RESUMO

Structural plasticity of dendritic spines is a key component of the refinement of synaptic connections during learning. Recent studies highlight a novel role for the NMDA receptor (NMDAR), independent of ion flow, in driving spine shrinkage and LTD. Yet little is known about the molecular mechanisms that link conformational changes in the NMDAR to changes in spine size and synaptic strength. Here, using two-photon glutamate uncaging to induce plasticity at individual dendritic spines on hippocampal CA1 neurons from mice and rats of both sexes, we demonstrate that p38 MAPK is generally required downstream of non-ionotropic NMDAR signaling to drive both spine shrinkage and LTD. In a series of pharmacological and molecular genetic experiments, we identify key components of the non-ionotropic NMDAR signaling pathway driving dendritic spine shrinkage, including the interaction between NOS1AP (nitric oxide synthase 1 adaptor protein) and neuronal nitric oxide synthase (nNOS), nNOS enzymatic activity, activation of MK2 (MAPK-activated protein kinase 2) and cofilin, and signaling through CaMKII. Our results represent a large step forward in delineating the molecular mechanisms of non-ionotropic NMDAR signaling that can drive shrinkage and elimination of dendritic spines during synaptic plasticity.SIGNIFICANCE STATEMENT Signaling through the NMDA receptor (NMDAR) is vitally important for the synaptic plasticity that underlies learning. Recent studies highlight a novel role for the NMDAR, independent of ion flow, in driving synaptic weakening and dendritic spine shrinkage during synaptic plasticity. Here, we delineate several key components of the molecular pathway that links conformational signaling through the NMDAR to dendritic spine shrinkage during synaptic plasticity.


Assuntos
Espinhas Dendríticas/metabolismo , Plasticidade Neuronal/fisiologia , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Região CA1 Hipocampal/fisiologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia
6.
Semin Thromb Hemost ; 45(6): 629-637, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31350735

RESUMO

Venous thromboembolism (VTE) is a common complication of cancer occurring in up to one-fifth of cancer patients. The risk of VTE, which includes deep venous thrombosis (DVT) and pulmonary embolism (PE), is increased up to seven-fold in patients with cancer. While the indications and contraindications to treatment for VTE patients with cancer parallel to those patients without cancer, the treatment of VTE is challenging for cancer patients who are three-fold more likely to have VTE recurrence than patients without cancer and who are also at increased risk of bleeding. While anticoagulant therapy is recommended for most cancer patients with VTE, some patients may benefit from alternative interventions, such as thrombolysis, thromboembolectomy, or placement of an inferior vena cava (IVC) filter. Recent data support the use of direct oral anticoagulants (DOACs) for treatment of cancer-associated VTE in select cancer patients and for primary prevention of thromboembolism in high-risk cancer patients. Individualized decision-making, keeping in consideration the patient's risk for thrombotic and bleeding events is essential.


Assuntos
Anticoagulantes/uso terapêutico , Neoplasias/tratamento farmacológico , Anticoagulantes/farmacologia , Humanos , Fatores de Risco , Resultado do Tratamento
7.
EMBO J ; 33(12): 1341-53, 2014 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-24705785

RESUMO

Postsynaptic density protein-95 (PSD-95) is a central element of the postsynaptic architecture of glutamatergic synapses. PSD-95 mediates postsynaptic localization of AMPA receptors and NMDA receptors and plays an important role in synaptic plasticity. PSD-95 is released from postsynaptic membranes in response to Ca(2+) influx via NMDA receptors. Here, we show that Ca(2+)/calmodulin (CaM) binds at the N-terminus of PSD-95. Our NMR structure reveals that both lobes of CaM collapse onto a helical structure of PSD-95 formed at its N-terminus (residues 1-16). This N-terminal capping of PSD-95 by CaM blocks palmitoylation of C3 and C5, which is required for postsynaptic PSD-95 targeting and the binding of CDKL5, a kinase important for synapse stability. CaM forms extensive hydrophobic contacts with Y12 of PSD-95. The PSD-95 mutant Y12E strongly impairs binding to CaM and Ca(2+)-induced release of PSD-95 from the postsynaptic membrane in dendritic spines. Our data indicate that CaM binding to PSD-95 serves to block palmitoylation of PSD-95, which in turn promotes Ca(2+)-induced dissociation of PSD-95 from the postsynaptic membrane.


Assuntos
Calmodulina/metabolismo , Hipocampo/citologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Modelos Neurológicos , Neurônios/metabolismo , Densidade Pós-Sináptica/metabolismo , Animais , Células Cultivadas , Proteína 4 Homóloga a Disks-Large , Fluorescência , Técnicas Histológicas , Immunoblotting , Imunoprecipitação , Espectroscopia de Ressonância Magnética , Conformação Proteica , Ratos
8.
Am J Med Genet A ; 176(12): 2704-2709, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30475443

RESUMO

The increasing use of next-generation sequencing, especially clinical exome sequencing, has revealed that individuals having two coexisting genetic conditions are not uncommon occurrences. This pilot study evaluates the efficacy of two methodologically distinct computational differential diagnosis generating tools-FindZebra and SimulConsult-in identifying multiple genetic conditions in a single patient. Clinical query terms were generated for each of 15 monogenic disorders that were effective in resulting in the top 10 list of differential diagnoses for each of the 15 monogenic conditions when entered into these bioinformatics tools. Then, the terms of over 125 pairings of these conditions were entered using each tool and the resulting list of diagnoses evaluated to determine how often both diagnoses of a pair were represented in that list. Neither tool was successful in identifying both members of a pair of conditions in greater than 40% of test cases. Disorder detection sensitivity was not homogeneous within a tool, with each tool favoring the identification of a subset of genetic conditions. In view of recent exome sequencing data showing an unexpectedly high prevalence of coexistent monogenic conditions, the results from this pilot study highlight a need for the development of computational tools designed to effectively generate differential diagnoses with consideration of the possibility of coexisting conditions.


Assuntos
Diagnóstico por Computador/métodos , Doenças Genéticas Inatas/diagnóstico , Doenças Genéticas Inatas/genética , Testes Genéticos/métodos , Pré-Escolar , Biologia Computacional/métodos , Diagnóstico por Computador/normas , Diagnóstico Diferencial , Testes Genéticos/normas , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Software , Navegador
9.
bioRxiv ; 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38854020

RESUMO

NMDA-type glutamate receptors (NMDARs) are widely recognized as master regulators of synaptic plasticity, most notably for driving long-term changes in synapse size and strength that support learning. NMDARs are unique among neurotransmitter receptors in that they require binding of both neurotransmitter (glutamate) and co-agonist (e.g. d -serine) to open the receptor channel, which leads to the influx of calcium ions that drive synaptic plasticity. Over the past decade, evidence has accumulated that NMDARs also support synaptic plasticity via ion flux-independent (non-ionotropic) signaling upon the binding of glutamate in the absence of co-agonist, although conflicting results have led to significant controversy. Here, we hypothesized that a major source of contradictory results can be attributed to variable occupancy of the co-agonist binding site under different experimental conditions. To test this hypothesis, we manipulated co-agonist availability in acute hippocampal slices from mice of both sexes. We found that enzymatic scavenging of endogenous co-agonists enhanced the magnitude of LTD induced by non-ionotropic NMDAR signaling in the presence of the NMDAR pore blocker, MK801. Conversely, a saturating concentration of d -serine completely inhibited both LTD and spine shrinkage induced by glutamate binding in the presence of MK801. Using a FRET-based assay in cultured neurons, we further found that d -serine completely blocked NMDA-induced conformational movements of the GluN1 cytoplasmic domains in the presence of MK801. Our results support a model in which d -serine inhibits ion flux-independent NMDAR signaling and plasticity, and thus d -serine availability could serve to modulate NMDAR signaling even when the NMDAR is blocked by magnesium. Significance Statement: NMDARs are glutamate-gated cation channels that are key regulators of neurodevelopment and synaptic plasticity and unique in their requirement for binding of a co-agonist (e.g. d -serine) in order for the channel to open. NMDARs have been found to drive synaptic plasticity via non-ionotropic (ion flux-independent) signaling upon the binding of glutamate in the absence of co-agonist, though conflicting results have led to controversy. Here, we found that d -serine inhibits non-ionotropic NMDAR-mediated LTD and LTD-associated spine shrinkage. Thus, a major source of the contradictory findings might be attributed to experimental variability in d -serine availability. In addition, the developmental regulation of d -serine levels suggests a role for non-ionotropic NMDAR plasticity during critical periods of plasticity.

10.
BMC Neurosci ; 14: 83, 2013 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-23915010

RESUMO

BACKGROUND: Previous studies associate lipid peroxidation with long-term memory (LTM) failure in a gastropod model (Lymnaea stagnalis) of associative learning and memory. This process involves activation of Phospholipase A2 (PLA2), an enzyme mediating the release of fatty acids such as arachidonic acid that form the precursor for a variety of pro-inflammatory lipid metabolites. This study investigated the effect of biologically realistic challenges of L. stagnalis host defense response system on LTM function and potential involvement of PLA2, COX and LOX therein. RESULTS: Systemic immune challenges by means of ß-glucan laminarin injections induced elevated H2O2 release from L. stagnalis circulatory immune cells within 3 hrs of treatment. This effect dissipated within 24 hrs after treatment. Laminarin exposure has no direct effect on neuronal activity. Laminarin injections disrupted LTM formation if training followed within 1 hr after injection but had no behavioural impact if training started 24 hrs after treatment. Intermediate term memory was not affected by laminarin injection. Chemosensory and motor functions underpinning the feeding response involved in this learning model were not affected by laminarin injection. Laminarin's suppression of LTM induction was reversed by treatment with aristolochic acid, a PLA2 inhibitor, or indomethacin, a putative COX inhibitor, but not by treatment with nordihydro-guaiaretic acid, a putative LOX inhibitor. CONCLUSIONS: A systemic immune challenge administered shortly before behavioural training impairs associative LTM function in our model that can be countered with putative inhibitors of PLA2 and COX, but not LOX. As such, this study establishes a mechanistic link between the state of activity of this gastropod's innate immune system and higher order nervous system function. Our findings underwrite the rapidly expanding view of neuroinflammatory processes as a fundamental, evolutionary conserved cause of cognitive and other nervous system disorders.


Assuntos
Inibidores Enzimáticos/uso terapêutico , Imunidade Inata/fisiologia , Transtornos da Memória/tratamento farmacológico , Fosfolipases A2/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , Análise de Variância , Animais , Córtex Cerebral/citologia , Condicionamento Psicológico/efeitos dos fármacos , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Glucanos , Hemócitos/efeitos dos fármacos , Hemócitos/metabolismo , Peróxido de Hidrogênio/metabolismo , Hipolipemiantes/toxicidade , Imunidade Inata/efeitos dos fármacos , Indometacina/farmacologia , Indometacina/uso terapêutico , Potenciação de Longa Duração/efeitos dos fármacos , Lymnaea , Transtornos da Memória/induzido quimicamente , Neurônios/efeitos dos fármacos , Polissacarídeos/toxicidade , Fatores de Tempo
11.
Artigo em Inglês | MEDLINE | ID: mdl-35840002

RESUMO

BACKGROUND: Since Kahlbaum's classic 19th-century description of catatonia, our conceptualization of this syndrome, as well treatment options for it, has advanced considerably. However, little is known about the current state of the catatonia literature since a comprehensive bibliometric analysis of it has not yet been undertaken. OBJECTIVE: The purpose of this study was to conduct a bibliometric analysis, along with a content analysis of articles reporting new findings, to better understand the catatonia literature and how catatonia research is changing. METHODS: Using the search term "Title(catatoni∗)" in Web of Science Core Collection for all available years (1965-2020), all available publications (articles, proceeding papers, reviews) pertaining directly to catatonia were identified, and metadata extracted. Semantic and coauthorship network analyses were conducted. A content analysis was also conducted on all available case reports, case series, and research articles written in English. RESULTS: A total of 1015 articles were identified representing 2861 authors, 346 journals, and 15,639 references. The average number of publications per year over the last 20 years (31.3) more than doubled in comparison to that in the 20 years prior (12.8). The top 3 most common journals were Psychosomatics/Journal of the Academy of Consultation-Liaison Psychiatry, Journal of ECT, and Schizophrenia Research, which represented 12.6% of all publications. Content analysis revealed that catatonia articles are increasingly published in nonpsychiatric journals. There was a notable paucity of clinical trials throughout the study period. Since 2003, articles on catatonia secondary to a general medical condition, as well as articles including child/adolescent patients and patients with autism spectrum disorder or intellectual disability, have made up increasing shares of the literature, with a smaller proportion of articles reporting periodic or recurrent catatonia. We noted a decrease in the proportion of articles detailing animal/in vitro studies, genetic/heredity studies, and clinical trials, along with stagnation in the proportion of neuroimaging studies. CONCLUSIONS: The catatonia literature is growing through contributions from authors and institutions across multiple countries. However, recent growth has largely been driven by increased case reports, with significant downturns observed in both clinical and basic science research articles. A dearth of clinical trials evaluating potential treatments remain a critical gap in the catatonia literature.


Assuntos
Transtorno do Espectro Autista , Catatonia , Esquizofrenia , Humanos , Catatonia/terapia , Lacunas de Evidências , Transtorno do Espectro Autista/complicações , Bibliometria , Esquizofrenia/complicações
12.
Cell Rep ; 42(8): 112928, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37542720

RESUMO

Identifying molecular circuits that control adipose tissue macrophage (ATM) function is necessary to understand how ATMs contribute to tissue homeostasis and obesity-induced insulin resistance. In this study, we find that mice with a myeloid-specific knockout of the miR-23-27-24 clusters of microRNAs (miRNAs) gain less weight on a high-fat diet but exhibit worsened glucose and insulin tolerance. Analysis of ATMs from these mice shows selectively reduced numbers and proliferation of a recently reported subset of lipid-associated CD9+Trem2+ ATMs (lipid-associated macrophages [LAMs]). Leveraging the role of miRNAs to control networks of genes, we use RNA sequencing (RNA-seq), functional screens, and biochemical assays to identify candidate target transcripts that regulate proliferation-associated signaling. We determine that miR-23 directly targets the mRNA of Eif4ebp2, a gene that restricts protein synthesis and proliferation in macrophages. Altogether, our study demonstrates that control of proliferation of a protective subset of LAMs by noncoding RNAs contributes to protection against diet-induced obesity metabolic dysfunction.


Assuntos
Resistência à Insulina , MicroRNAs , Camundongos , Animais , Tecido Adiposo/metabolismo , Obesidade/genética , Obesidade/metabolismo , Macrófagos/metabolismo , Resistência à Insulina/fisiologia , MicroRNAs/genética , MicroRNAs/metabolismo , Dieta Hiperlipídica , Lipídeos , Proliferação de Células , Camundongos Endogâmicos C57BL , Inflamação/metabolismo , Glicoproteínas de Membrana/metabolismo , Receptores Imunológicos/metabolismo
13.
Neuropharmacology ; 210: 109019, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35278420

RESUMO

NMDA receptors play vital roles in a broad array of essential brain functions, from synaptic transmission and plasticity to learning and memory. Historically, the fundamental roles of NMDARs were attributed to their specialized properties of ion flux. More recently, it has become clear that NMDARs also signal in an ion flux-independent manner. Here, we review these non-ionotropic NMDAR signaling mechanisms that have been reported to contribute to a broad array of neuronal functions and dysfunctions including synaptic transmission and plasticity, cell death and survival, and synaptic alterations associated with neurological disorders.


Assuntos
Receptores de N-Metil-D-Aspartato , Transmissão Sináptica , Aprendizagem , Plasticidade Neuronal/fisiologia , Neurônios/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Transdução de Sinais/fisiologia , Transmissão Sináptica/fisiologia
14.
Int J Radiat Oncol Biol Phys ; 114(2): 283-292, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35667529

RESUMO

PURPOSE: In addition to established prognostic factors in low-grade glioma (LGG), studies suggest a sexual dimorphism with male sex portending worse prognosis. Our objective was to identify the effect of sex on presentation and outcomes in LGG. METHODS AND MATERIALS: We conducted a retrospective cohort study of adults (aged ≥18 years) diagnosed with LGG (World Health Organization 2016 grade 2 glioma). Patients with IDH wild-type tumors were excluded. Patients were matched between male and female sex by age, treatment, and surgery via propensity score matching. Patient, tumor, and treatment characteristics were analyzed by sex. Endpoints included overall survival (OS), next intervention-free survival (NIFS), progression-free survival, and malignant transformation-free survival. Kaplan-Meier analyses and Cox proportional hazards regression multivariable analysis with backward elimination were completed. RESULTS: Of the 532 patients identified, 258 (48%) were men. Men were more likely to present with seizure (69.38% vs 56.57%, P = .002), but no other statistically significant differences between sexes at presentation were identified. Five-year OS was higher in women at 87% (95% confidence interval [CI], 83%-91%) versus 78% (95% CI, 73%-84%) in men (P = .0045). NIFS was significantly higher in female patients at 68% (95% CI, 62%-74%) versus 57% (95% CI, 51%-64%) in men (P = .009). On multivariable analysis, female sex was independently associated with improved OS (hazard ratio [HR], 1.54; 95% CI, 1.16-2.05; P = .002), NIFS (HR, 1.42; 95% CI, 1.42; P = .004), and malignant transformation-free survival (HR, 1.62; 95% CI, 1.24-2.12; P = .0004). In patients with molecularly defined LGG (IDH and 1p19q status; n = 291), female sex remained independently associated with improved OS (HR, 1.79; 95% CI, 1.16-2.77; P = .008) and NIFS (HR, 1.45; 95% CI, 1.07-1.96; P = .016). CONCLUSIONS: In this study, female sex was independently associated with improved outcomes. These findings support intrinsic sex-specific differences in LGG behavior, justifying further studies to optimize management and therapeutics based on sex.


Assuntos
Neoplasias Encefálicas , Glioma , Adolescente , Adulto , Neoplasias Encefálicas/patologia , Feminino , Glioma/patologia , Humanos , Masculino , Prognóstico , Estudos Retrospectivos , Caracteres Sexuais
15.
Cell Rep ; 34(4): 108664, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33503425

RESUMO

Experience-dependent refinement of neuronal connections is critically important for brain development and learning. Here, we show that ion-flow-independent NMDA receptor (NMDAR) signaling is required for the long-term dendritic spine growth that is a vital component of brain circuit plasticity. We find that inhibition of p38 mitogen-activated protein kinase (p38 MAPK), which is downstream of non-ionotropic NMDAR signaling in long-term depression (LTD) and spine shrinkage, blocks long-term potentiation (LTP)-induced spine growth but not LTP. We hypothesize that non-ionotropic NMDAR signaling drives the cytoskeletal changes that support bidirectional spine structural plasticity. Indeed, we find that key signaling components downstream of non-ionotropic NMDAR function in LTD-induced spine shrinkage are also necessary for LTP-induced spine growth. Furthermore, NMDAR conformational signaling with coincident Ca2+ influx is sufficient to drive CaMKII-dependent long-term spine growth, even when Ca2+ is artificially driven through voltage-gated Ca2+ channels. Our results support a model in which non-ionotropic NMDAR signaling gates the bidirectional spine structural changes vital for brain plasticity.


Assuntos
Espinhas Dendríticas/metabolismo , N-Metilaspartato/metabolismo , Plasticidade Neuronal/fisiologia , Receptores de N-Metil-D-Aspartato/metabolismo , Humanos
16.
J Thromb Haemost ; 18(3): 651-659, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31808607

RESUMO

BACKGROUND: Previous studies suggest isolated distal deep vein thrombosis (IDDVT) has a self-limited clinical course. However, these studies excluded cancer patients, who remain a high-risk population. In addition, studies to evaluate the long-term clinical outcomes of IDDVT in cancer patients have been limited. Here, we report outcomes from our experience in treating cancer-associated IDDVT versus proximal venous thromboembolism (VTE). METHODS: We prospectively evaluated a cohort of patients referred to our cancer-associated thrombosis clinic from August 2014 through May 2018. We compared clinical characteristics, anticoagulation prescription, VTE recurrence, overall survival, major bleeding, and subsequent hospital admission between cancer patients with IDDVT and proximal VTE. A propensity score matching method was used to reduce bias from confounding variables. RESULTS: Of 1100 patients referred to the clinic, 124 IDDVT and 178 proximal VTE events were analyzed. After propensity score matching, 96 patients were included in each cohort. There was no difference in the rate of recurrent VTE between cancer patients with proximal VTE vs IDDVT, with or without matching (matched: hazard ratio [HR], 0.77; 95% confidence interval [CI], 0.31-1.92; P = .58). There was no difference in overall survival between cancer patients with proximal VTE vs. IDDVT with or without matching (matched: HR, 1.18; 95% CI, 0.77-1.82; P = .45). Furthermore, subsequent hospital admissions and major bleeding events were similar between patients with proximal VTE events versus IDDVT. CONCLUSIONS: Cancer patients with IDDVT have similar outcomes as their proximal counterparts, including rate of recurrence and overall survival. These findings suggest treatment of cancer-associated IDDVT should mirror treatment of proximal events.


Assuntos
Neoplasias , Tromboembolia Venosa , Trombose Venosa , Anticoagulantes/uso terapêutico , Coagulação Sanguínea , Hemorragia , Humanos , Neoplasias/complicações , Recidiva , Fatores de Risco , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/tratamento farmacológico
17.
BMJ Open ; 10(3): e033092, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32156763

RESUMO

INTRODUCTION: More women experience cardiac pain related to coronary artery disease and cardiac procedures compared with men. The overall goal of this programme of research is to develop an integrated smartphone and web-based intervention (HEARTPA♀N) to help women recognise and self-manage cardiac pain. METHODS AND ANALYSIS: This protocol outlines the mixed methods strategy used for the development of the HEARTPA♀N content/core feature set (phase 2A), usability testing (phase 2B) and evaluation with a pilot randomised controlled trial (RCT) (phase 3). We are using the individual and family self-management theory, mobile device functionality and pervasive information architecture of mHealth interventions, and following a sequential phased approach recommended by the Medical Research Council to develop HEARTPA♀N. The phase 3 pilot RCT will enable us to refine the prototype, inform the methodology and calculate the sample size for a larger multisite RCT (phase 4, future work). Patient partners have been actively involved in setting the HEARTPA♀N research agenda, including defining patient-reported outcome measures for the pilot RCT: pain and health-related quality of life (HRQoL). As such, the guidelines for Inclusion of Patient-Reported Outcomes in Clinical Trial Protocols (SPIRIT-PRO) are used to report the protocol for the pilot RCT (phase 3). Quantitative data (eg, demographic and clinical information) will be summarised using descriptive statistics (phases 2AB and 3) and a content analysis will be used to identify themes (phase 2AB). A process evaluation will be used to assess the feasibility of the implementation of the intervention and a preliminary efficacy evaluation will be undertaken focusing on the outcomes of pain and HRQoL (phase 3). ETHICS AND DISSEMINATION: Ethics approval was obtained from the University of Toronto (36415; 26 November 2018). We will disseminate knowledge of HEARTPA♀N through publication, conference presentation and national public forums (Café Scientifique), and through fact sheets, tweets and webinars. TRIAL REGISTRATION NUMBER: NCT03800082.


Assuntos
Angina Pectoris/diagnóstico , Intervenção Baseada em Internet/estatística & dados numéricos , Smartphone/instrumentação , Telemedicina/instrumentação , Adulto , Angina Pectoris/epidemiologia , Angina Pectoris/etiologia , Canadá/epidemiologia , Estudos de Casos e Controles , Feminino , Grupos Focais/estatística & dados numéricos , Humanos , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Projetos Piloto , Qualidade de Vida , Autogestão , Telemedicina/estatística & dados numéricos , Design Centrado no Usuário
18.
BMJ Case Rep ; 12(11)2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31776144

RESUMO

We report a case of a 73-year-old woman who developed pancreatic adenocarcinoma and presented with a colonic obstruction due to isolated metastasis to the colon, the primary lesion being diagnosed subsequently on imaging. The histopathological findings of the pancreatic mass exhibited a morphology and immunohistochemical profile consistent with a pancreatic adenocarcinoma and led to further analysis of the colonic pathology which ultimately confirmed the lesion was a pancreatic metastases rather than a primary colonic carcinoma. As the pancreatic cancer had metastasised to the colon, it was inoperable. The patient continued on palliative chemotherapy and passed 7 months after presentation for evaluation of her pancreatic mass due to progression of the pancreatic cancer. This report demonstrates a rare presentation of pancreatic cancer with colonic obstruction due to isolated metastatic disease and illustrated the importance of careful evaluation of histopathological findings.


Assuntos
Adenocarcinoma/complicações , Adenocarcinoma/secundário , Doenças do Colo/etiologia , Neoplasias do Colo/complicações , Neoplasias do Colo/secundário , Obstrução Intestinal/etiologia , Neoplasias Pancreáticas/patologia , Feminino , Humanos , Pessoa de Meia-Idade
19.
Int J Radiat Oncol Biol Phys ; 105(5): 1106-1112, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31461674

RESUMO

PURPOSE: Malignant transformation (MT) of adult grade 2 glioma (low-grade glioma [LGG]) is associated with adverse survival. We sought to describe the incidence, outcomes, and risk factors for MT of molecularly classified LGG. METHODS AND MATERIALS: We reviewed a single-institutional database of adults who received a diagnosis of LGG with data allowing for molecular classification from 1980 to 2018 to evaluate time to MT and its associated risk factors. MT was defined as pathologic confirmation of grade 3-4 glioma and/or imaging characteristics consistent with MT by multidisciplinary consensus. RESULTS: Among the included 486 adults with molecularly classified LGG, median age was 39 years (range, 18-78), median tumor size was 3.9 cm (range, 0.3-13.0), and 262 (54%) were male. Molecular classification was IDHmut1p/19qcodel in 169 (35%), IDHmut1p/19qintact in 125 (26%), and IDHwt in 192 (40%) patients. Adjuvant management was observation in 246 (51%) patients, temozolomide alone in 82 (16%), radiation therapy alone in 63 (13%), and radiation therapy concurrent with temozolomide in 81 (17%). Temozolomide monotherapy was more likely to be given to IDHmut1p/19qcodel patients (P < .001). Median follow-up was 5.3 years. MT occurred in 84 (17%) patients, with a 5-year freedom from MT of 86% (95% confidence interval [CI], 82%-90%). Median overall survival after MT was 2.4 years (95% CI, 1.5-3.3) and was associated with molecular classification (P = .03) and grade at MT (P < .001). Factors associated with MT were male sex (hazard ratio [HR], 2.1; 95% CI, 1.2-3.6; P = .009), tumor size ≥5 cm (HR, 3.5; 95% CI, 2.0-6.2; P < .001), IDHmut1p/19qintact (HR, 2.7; 95% CI, 1.3-5.6; P = .009) or IDHwt classification (HR, 5.5; 95% CI, 2.5-11.8; P < .001), and adjuvant temozolomide monotherapy (HR, 3.8; 95% CI, 1.4-10.3; P = .008). CONCLUSIONS: MT of LGG has a poor prognosis associated with unfavorable molecular groups. Analysis of our large cohort identified adjuvant temozolomide monotherapy as the only modifiable risk factor for MT and provides the first clinical evidence of temozolomide-associated MT among molecularly classified adult LGG. This novel finding supplements our understanding of temozolomide-induced hypermutation and informs precision management of LGG.


Assuntos
Neoplasias Encefálicas/patologia , Transformação Celular Neoplásica/patologia , Glioma/patologia , Adulto , Idoso , Antineoplásicos Alquilantes/efeitos adversos , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/terapia , Transformação Celular Neoplásica/induzido quimicamente , Transformação Celular Neoplásica/genética , Quimiorradioterapia/métodos , Quimioterapia Adjuvante , Feminino , Glioma/genética , Glioma/mortalidade , Glioma/terapia , Humanos , Isocitrato Desidrogenase/genética , Masculino , Pessoa de Meia-Idade , Mutação , Fatores Sexuais , Temozolomida/efeitos adversos , Temozolomida/uso terapêutico , Carga Tumoral , Conduta Expectante
20.
Int J Radiat Oncol Biol Phys ; 104(5): 1099-1105, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31022510

RESUMO

PURPOSE: To identify risk factors for progression-free survival (PFS) in the molecular era among patients with low-grade glioma (LGG) who undergo gross total resection (GTR) followed by initial observation. METHODS AND MATERIALS: We reviewed patients with World Health Organization grade 2 LGG treated at a single institution. We included only those who underwent magnetic resonance imaging (MRI)-confirmed GTR followed by initial observation. Molecular classification was obtained at either the time of diagnosis or pathology review. Cox proportional hazards regression, the Kaplan-Meier method, and the log-rank test were used. P values <.05 were considered statistically significant. RESULTS: We included 144 patients who underwent MRI-confirmed GTR between 1994 and 2014 followed by initial observation. Median age was 29 years (interquartile range [IQR], 18-41), median tumor size was 2.7 cm (IQR, 1.8-4.0), and median follow-up was 81 months (IQR, 36-132). Molecular classification was 13% IDH-mutant 1p19q-codeleted; 21% IDH-mutant 1p19q-intact; 39% IDH1-R132H-wildtype; and 28% undetermined. For the entire cohort, 5- and 10-year PFS and overall survival were 71% and 53%, and 98% and 90%, respectively. On multivariate analysis, factors associated with worse PFS included increasing age at diagnosis (hazard ratio [HR], 1.05; 95% CI, 1.00-1.09; P = .03), increasing preoperative tumor size (HR, 1.07; 95% CI, 1.04-1.10; P < .0001), and IDH-mutant 1p19q-intact classification (HR, 3.18; 95% CI, 1.15-8.74, P = .025). Median PFS for patients with IDH-mutant 1p19q-codeleted, IDH-mutant 1p19q-intact, and IDH1-R132H-wildtype tumors were 113 months, 56 months, and not reached, respectively. Molecular classification was significantly associated with PFS (P < .0001) but not overall survival (P = .20). CONCLUSIONS: Among patients with LGG who undergo MRI-confirmed GTR and initial observation in the molecular era, increasing age, increasing tumor size, and IDH-mutant 1p19q-intact classification are associated with worse PFS. Because tumor progression is associated with adverse health-related quality of life, these factors may aid clinicians and patients in the shared decision-making process regarding goals of surgery and timing of postoperative therapy. Further study is required to elucidate why IDH-mutant 1p19q-intact LGGs are at higher risk for early progression.


Assuntos
Neoplasias Encefálicas/cirurgia , Glioma/cirurgia , Adolescente , Adulto , Fatores Etários , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Progressão da Doença , Feminino , Glioma/diagnóstico por imagem , Glioma/genética , Glioma/patologia , Humanos , Isocitrato Desidrogenase/genética , Estimativa de Kaplan-Meier , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Intervalo Livre de Progressão , Modelos de Riscos Proporcionais , Qualidade de Vida , Fatores de Risco , Análise de Sobrevida , Carga Tumoral , Adulto Jovem
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