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1.
Tumour Biol ; 46(s1): S163-S175, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37840516

RESUMO

BACKGROUND: Serum tumor markers (STM) may complement imaging and provide additional clinical information for patients with non-small cell lung cancer (NSCLC). OBJECTIVE: To determine whether STMs can predict outcomes in patients with stable disease (SD) after initial treatment. METHODS: This single-center, prospective, observational trial enrolled 395 patients with stage III/IV treatment-naïve NSCLC; of which 263 patients were included in this analysis. Computed Tomography (CT) scans were performed and STMs measured before and after initial treatment (two cycles of chemotherapy and/or an immune checkpoint inhibitor or tyrosine kinase inhibitor); analyses were based on CT and STM measurements obtained at first CT performed after cycle 2 only PFS and OS were analyzed by Kaplan-Meier curves and Cox-proportional hazard models. RESULTS: When patients with SD (n = 100) were split into high- and low-risk groups based on CYFRA 21-1, CEA and CA 125 measurements using an optimized cut-off, a 4-fold increase risk of progression or death was estimated for high- vs low-risk SD patients (PFS, HR 4.17; OS, 3.99; both p < 0.0001). Outcomes were similar between patients with high-risk SD or progressive disease (n = 35) (OS, HR 1.17) and between patients with low-risk SD or partial response (n = 128) (PFS, HR 0.98; OS, 1.14). CONCLUSIONS: STMs can provide further guidance in patients with indeterminate CT responses by separating them into high- and low-risk groups for future PFS and OS events.


Assuntos
Antígenos de Neoplasias , Carcinoma Pulmonar de Células não Pequenas , Queratina-19 , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Prognóstico , Estudos Prospectivos , Tomografia Computadorizada por Raios X
2.
Am J Dermatopathol ; 46(5): 287-291, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38457688

RESUMO

ABSTRACT: Lichen sclerosus (LS) is a frequently encountered inflammatory skin disorder characterized by whitened, atrophic patches that can cause pain and pruritus. The underlying cause of this condition remains unknown. Primarily affecting the genital area, this condition carries an increased risk of developing cutaneous cancers and frequently co-occurs with autoimmune disorders. Our retrospective study aimed to explore histologic features of LS, with a particular focus on a newly established finding and its potential implications. We examined 53 histologic cases of LS collected over 2 years. Experienced pathologists evaluated and reached a consensus on the assignment of histologic features. Patient charts were manually reviewed to gather relevant demographic and clinical data. Statistical analysis was performed using IBM SPSS Statistics (2021). Of the 53 total patients identified as meeting criteria for inclusion in this study, only 8 (15%) were male. Eight cases (15%) demonstrated perineural inflammatory infiltrate. Notably, half of all samples from male patients exhibited perineural inflammatory infiltrate. A statistically significant increase ( P < 0.01) in the presence of dermal plasma cells was identified in cases with perineural inflammation versus cases without this feature. The findings of our study highlight the recurrent nature of perineural inflammation in LS, providing valuable insights into this condition. Furthermore, we observed a notable correlation between perineural inflammation, male patients, and the presence of dermal plasma cells. These discoveries contribute to a better understanding of the underlying mechanisms of LS and suggest avenues for future research into the condition.


Assuntos
Doenças Autoimunes , Líquen Escleroso e Atrófico , Humanos , Masculino , Feminino , Líquen Escleroso e Atrófico/complicações , Líquen Escleroso e Atrófico/patologia , Estudos Retrospectivos , Inflamação , Prurido
3.
Methods ; 195: 103-112, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33838269

RESUMO

Subjective belief elicitation about uncertain events has a long lineage in the economics and statistics literatures. Recent developments in the experimental elicitation and statistical estimation of subjective belief distributions allow inferences about whether these beliefs are biased relative to expert opinion, and the confidence with which they are held. Beliefs about COVID-19 prevalence and mortality interact with risk management efforts, so it is important to understand relationships between these beliefs and publicly disseminated statistics, particularly those based on evolving epidemiological models. The pandemic provides a unique setting over which to bracket the range of possible COVID-19 prevalence and mortality outcomes given the proliferation of estimates from epidemiological models. We rely on the epidemiological model produced by the Institute for Health Metrics and Evaluation together with the set of epidemiological models summarised by FiveThirtyEight to bound prevalence and mortality outcomes for one-month, and December 1, 2020 time horizons. We develop a new method to partition these bounds into intervals, and ask subjects to place bets on these intervals, thereby revealing their beliefs. The intervals are constructed such that if beliefs are consistent with epidemiological models, subjects are best off betting the same amount on every interval. We use an incentivised experiment to elicit beliefs about COVID-19 prevalence and mortality from 598 students at Georgia State University, using six temporally-spaced waves between May and November 2020. We find that beliefs differ markedly from epidemiological models, which has implications for public health communication about the risks posed by the virus.


Assuntos
COVID-19/mortalidade , COVID-19/psicologia , Cultura , Tomada de Decisões , Modelo de Crenças de Saúde , Inquéritos e Questionários/normas , COVID-19/epidemiologia , Tomada de Decisões/fisiologia , Humanos , Mortalidade/tendências , Prevalência
4.
Geneva Risk Insur Rev ; 47(1): 66-97, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33642955

RESUMO

There is widespread concern in developing countries with the expansion of formal insurance products to help manage significant risks. These concerns arise primarily from a lack of understanding of insurance products, general failures of financial literacy and the need to use relatively exotic products in order to keep costs down for poor households. We investigate the importance of incentivized measures for general understanding, as well as domain-specific knowledge of the decision context on the purchase and the quality of index insurance decisions. We evaluate the quality of financial decisions by comparing the individual expected welfare outcomes of a number of decisions each individual makes to purchase index insurance or not. We find that excess purchase is an important driver of welfare losses, and that our incentivized measure of domain-specific literacy plays a critical role in bringing about better quality index insurance decisions. Supplementary Information: The online version contains supplementary material available at 10.1057/s10713-020-00060-1.

5.
Mol Cancer ; 14: 85, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25889730

RESUMO

BACKGROUND: Among women worldwide, breast cancer is the most commonly diagnosed cancer, and the second leading cause of cancer-related deaths. Improved understanding of breast tumourigenesis may facilitate the development of more effective therapies. Peroxisome proliferator-activated receptor (PPAR)γ is a transcription factor that regulates genes involved in insulin sensitivity and adipogenesis. Previously, we showed, using 7,12-dimethylbenz [a] anthracene (DMBA)-treated haploinsufficient PPARγ mice, that PPARγ suppresses breast tumour progression; however, the PPARγ expressing cell types and mechanisms involved remain to be clarified. Here, the role of PPARγ expression and activation in mammary epithelial cells (MG) with respect to DMBA-mediated breast tumourigenesis was investigated. METHODS: PPARγ MG knockout (PPARγ-MG KO) mice and their congenic, wild-type controls (PPARγ-WT) were treated once a week for six weeks by oral gavage with 1 mg DMBA dissolved in corn oil and maintained on a normal chow diet. At week 7, mice were randomly divided into those maintained on a normal chow diet (DMBA Only; PPARγ-WT: n = 25 and PPARγ-MG KO: n = 39) or those receiving a diet supplemented with the PPARγ ligand, rosiglitazone (ROSI, 4 mg/kg/day) (DMBA + ROSI; PPARγ-WT: n = 34 and PPARγ-MG KO: n = 17) for the duration of the 25-week study. RESULTS: Compared to DMBA Only-treated PPARγ-WTs, both breast tumour susceptibility and serum levels of proinflammatory and chemotactic cytokines, namely IL-4, eotaxin, GM-CSF, IFN-γ, and MIP-1α, were decreased among PPARγ-MG KOs. Cotreatment with ROSI significantly reduced breast tumour progression among PPARγ-WTs, correlating with increased BRCA1 and decreased VEGF and COX-2 protein expression levels in breast tumours; whereas, surprisingly DMBA + ROSI-treated PPARγ-MG KOs showed increased breast tumourigenesis, correlating with activation of COX-2. CONCLUSION: These novel data suggest MG-specific PPARγ expression and signaling is critical during breast tumourigenesis, and may serve as a strong candidate predictive biomarker for response of breast cancer patients to the use of therapeutic strategies that include PPARγ ligands.


Assuntos
Progressão da Doença , Células Epiteliais/metabolismo , Glândulas Mamárias Animais/metabolismo , Neoplasias Mamárias Animais/metabolismo , Neoplasias Mamárias Experimentais/metabolismo , PPAR gama/metabolismo , Transdução de Sinais , 9,10-Dimetil-1,2-benzantraceno , Animais , Proteína BRCA1/metabolismo , Citocinas/sangue , Células Epiteliais/patologia , Feminino , Deleção de Genes , Glândulas Mamárias Animais/patologia , Neoplasias Mamárias Animais/sangue , Neoplasias Mamárias Animais/patologia , Neoplasias Mamárias Experimentais/sangue , Neoplasias Mamárias Experimentais/patologia , Camundongos Knockout , Modelos Biológicos , Especificidade de Órgãos , Carga Tumoral
6.
Int J Cancer ; 134(5): 1055-66, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23934545

RESUMO

Breast cancer is the leading cause of new cancer diagnoses among women. Using peroxisome proliferator-activated receptor (PPAR)γ((+/-)) mice, we showed normal expression of PPARγ was critical to stop 7,12-dimethylbenz[a]anthracene (DMBA)-induced breast tumorigenesis. PPARγ is expressed in many breast cell types including mammary secretory epithelial (MSE) cells. MSEs proliferate as required during pregnancy, and undergo apoptosis or reversible transdifferentiation during involution once lactation is complete. Thus, MSE-specific loss of PPARγ was hypothesized to enhance DMBA-mediated breast tumorigenesis. To test this, MSE cell-specific PPARγ knockout (PPARγ-MSE KO) and control (PPARγ-WT) mice were generated, mated and allowed to nurse for three days. One week after involution, dams were treated with DMBA to initiate breast tumors, and randomized on week 7 to continue receiving a normal chow diet (DMBA Only: PPARγ-WT, n = 15; PPARγ-MSE KO, n = 25) or one supplemented with a PPARγ activating drug (DMBA + ROSI: PPARγ-WT, n = 17; PPARγ-MSE KO, n = 24), and monitored for changes in breast tumor outcomes. PPARγ-MSE KOs had significantly lower overall survival and decreased mammary tumor latency as compared to PPARγ-WT controls. PPARγ activation significantly reduced DMBA-mediated malignant mammary tumor volumes irrespective of genotype. MSE-specific PPARγ loss resulted in decreased mammary gland expression of PTEN and Bax, increased superoxide anion production, and elevated serum eotaxin and RANTES, creating a protumorigenic environment. Moreover, PPARγ activation in MSEs delayed mammary tumor growth in part by down-regulating Cox-1, Cox-2 and cyclin D1. Collectively, these studies highlight a protective role of MSE-specific PPARγ during breast tumorigenesis, and support a novel chemotherapeutic role of PPARγ activation in breast cancer.


Assuntos
Glândulas Mamárias Animais/metabolismo , Neoplasias Mamárias Experimentais/etiologia , PPAR gama/fisiologia , 9,10-Dimetil-1,2-benzantraceno , Animais , Células Epiteliais/metabolismo , Feminino , Neoplasias Mamárias Experimentais/metabolismo , Camundongos , Camundongos Knockout , PTEN Fosfo-Hidrolase/análise , Proteína X Associada a bcl-2/análise
7.
J Med Chem ; 66(17): 12185-12202, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37651366

RESUMO

Abnormal α-synuclein (α-syn) aggregation characterizes α-synucleinopathies, including Parkinson's disease (PD) and multiple system atrophy (MSA). However, no suitable positron emission tomography (PET) radiotracer for imaging α-syn in PD and MSA exists currently. Our structure-activity relationship studies identified 4-methoxy-N-(4-(3-(pyridin-2-yl)-3,8-diazabicyclo[3.2.1]octan-8-yl)phenyl)benzamide (4i) as a PET radiotracer candidate for imaging α-syn. In vitro assays revealed high binding of 4i to recombinant α-syn fibrils (inhibition constant (Ki) = 6.1 nM) and low affinity for amyloid beta (Aß) fibrils in Alzheimer's disease (AD) homogenates. However, [3H]4i also exhibited high specific binding to AD, progressive supranuclear palsy, and corticobasal degeneration tissues as well as PD and MSA tissues, suggesting notable affinity to tau. Nevertheless, the specific binding to pathologic α-syn aggregates in MSA post-mortem brain tissues was significantly higher than in PD tissues. This finding demonstrated the potential use of [11C]4i as a PET tracer for imaging α-syn in MSA patients. Nonhuman primate PET studies confirmed good brain uptake and rapid washout for [11C]4i.


Assuntos
Doença de Alzheimer , Atrofia de Múltiplos Sistemas , Doença de Parkinson , Animais , alfa-Sinucleína , Atrofia de Múltiplos Sistemas/diagnóstico por imagem , Peptídeos beta-Amiloides , Tomografia por Emissão de Pósitrons , Encéfalo/diagnóstico por imagem
8.
Carcinogenesis ; 33(7): 1412-20, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22581835

RESUMO

Peroxisome proliferator-activated receptor (PPAR)γ regulates the expression of genes essential for fat storage, primarily through its activity in adipocytes. It also has a role in carcinogenesis. PPARγ normally stops the in vivo progression of 7,12-dimethylbenz[a]anthracene (DMBA)-mediated breast tumours as revealed with PPARγ haploinsufficient mice. Since many cell types associated with the mammary gland express PPARγ, each with unique signal patterns, this study aimed to define which tissues are required for PPARγ-dependent antitumour effects. Accordingly, adipocyte-specific PPARγ knockout (PPARγ-A KO) mice and their wild-type (PPARγ-WT) controls were generated, and treated with DMBA for 6 weeks to initiate breast tumorigenesis. On week 7, mice were randomized to continue on normal chow diet or one supplemented with rosiglitazone (ROSI), and followed for 25 weeks for tumour outcomes. In PPARγ-A KO versus PPARγ-WT mice, malignant mammary tumour incidence was significantly higher and mammary tumour latency was decreased. DMBA + ROSI treatment reduced average mammary tumour volumes by 50%. Gene expression analyses of mammary glands by quantitative real-time polymerase chain reaction and immunofluorescence indicated that untreated PPARγ-A KOs had significantly decreased BRCA1 expression in mammary stromal adipocytes. Compared with PPARγ-WT mice, serum leptin levels in PPARγ-A KOs were also significantly higher throughout the study. Together, these data are the first to suggest that in vivo PPARγ expression in mammary stromal adipocytes attenuates breast tumorigenesis through BRCA1 upregulation and decreased leptin secretion. This study supports a protective effect of activating PPARγ as a novel chemopreventive therapy for breast cancer.


Assuntos
Adipócitos/metabolismo , Neoplasias Mamárias Experimentais/prevenção & controle , PPAR gama/fisiologia , Células Estromais/metabolismo , Animais , Sequência de Bases , Primers do DNA , Ensaio de Imunoadsorção Enzimática , Feminino , Camundongos , Camundongos Knockout , PPAR gama/genética , Reação em Cadeia da Polimerase em Tempo Real , Rosiglitazona , Tiazolidinedionas/administração & dosagem
9.
Curr Opin Cell Biol ; 17(1): 55-61, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15661519

RESUMO

Stereocilia, the mechanosensitive protrusions in hair cells, are organized into rows of graded heights forming precisely uniform staircase patterns. The actin turnover process in stereocilia follows a treadmill model in which the rate of treadmilling is scaled to the stereocilium's length. Myosin XVa, which is present at the site of actin polymerization at concentrations proportional to the length of the actin filament bundles, plays a combined role with the treadmill machinery in regulating the steady state length of these actin protrusions, together with other myosins localized alongside the actin bundles.


Assuntos
Cílios/fisiologia , Células Ciliadas Auditivas/fisiologia , Células Ciliadas Auditivas/ultraestrutura , Actinas/química , Actinas/metabolismo , Animais , Citoesqueleto/metabolismo , Proteínas de Fluorescência Verde/química , Humanos , Microscopia Confocal , Microscopia Eletrônica de Varredura , Miosinas/química
10.
Exp Econ ; 25(3): 795-823, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35018135

RESUMO

The COVID-19 pandemic presents a remarkable opportunity to put to work all of the research that has been undertaken in past decades on the elicitation and structural estimation of subjective belief distributions as well as preferences over atemporal risk, patience, and intertemporal risk. As contributors to elements of that research in laboratories and the field, we drew together those methods and applied them to an online, incentivized experiment in the United States. We have two major findings. First, the atemporal risk premium during the COVID-19 pandemic appeared to change significantly compared to before the pandemic, consistent with theoretical results of the effect of increased background risk on foreground risk attitudes. Second, subjective beliefs about the cumulative level of deaths evolved dramatically over the period between May and November 2020, a volatile one in terms of the background evolution of the pandemic. Supplementary Information: The online version contains supplementary material available at 10.1007/s10683-021-09738-3.

11.
Opt Lett ; 36(23): 4557-9, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-22139241

RESUMO

Coupled photonic oscillators and resonators are sensitive to unavoidable nanoscale disorder, and localization in periodic structures induced by disorder leads eventually to a complete collapse of the bandwidth, which is generally considered problematic for device applications. Here, we investigate the dependence of bandwidth collapse on the interresonator coupling coefficient, a parameter controllable by lithography or device operation.

12.
Front Aging Neurosci ; 13: 704041, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34220490

RESUMO

Poly (ADP-ribose) (PAR) is a negatively charged polymer that is biosynthesized by Poly (ADP-ribose) Polymerase-1 (PARP-1) and regulates various cellular processes. Alpha-synuclein (αSyn) is an intrinsically disordered protein (IDP) that has been directly implicated with driving the onset and progression of Parkinson's disease (PD). The mechanisms by which α-synuclein (αSyn) elicits its neurotoxic effects remain unclear, though it is well established that the main components of Lewy bodies (LBs) and Lewy neurites (LNs) in PD patients are aggregated hyperphosphorylated (S129) forms of αSyn (pαSyn). In the present study, we used immunofluorescence-based assays to explore if PARP-1 enzymatic product (PAR) promotes the aberrant cytoplasmic accumulation of pαSyn. We also performed quantitative measurements using in situ proximity ligation assays (PLA) on a transgenic murine model of α-synucleinopathy (M83-SNCA∗A53T) and post mortem PD/PDD patient samples to characterize PAR-pαSyn interactions. Additionally, we used bioinformatic approaches and site-directed mutagenesis to identify PAR-binding regions on αSyn. In summary, our studies show that PAR-pαSyn interactions are predominantly observed in PD-relevant transgenic murine models of αSyn pathology and post mortem PD/PDD patient samples. Moreover, we confirm that the interactions between PAR and αSyn involve electrostatic forces between negatively charged PAR and lysine residues on the N-terminal region of αSyn.

13.
Opt Express ; 18(25): 26505-16, 2010 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-21165002

RESUMO

In contrast to recent reports of localization-impaired transport in long slow-light waveguides, we demonstrate light transport in silicon coupled-resonator optical waveguides (CROWs) consisting of up to 235 coupled microrings without localization over frequency bands that are several hundred gigahertz wide. Furthermore, from the unique statistical signatures provided by time-domain propagation delay measurements, we demonstrate the spectrally correlated nature of light propagation in CROWs.


Assuntos
Refratometria/instrumentação , Transdutores , Simulação por Computador , Desenho Assistido por Computador , Interpretação Estatística de Dados , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Modelos Estatísticos , Espalhamento de Radiação
14.
Opt Lett ; 35(18): 3030-2, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20847768

RESUMO

The dispersion of the waveguides that constitute microring resonators can considerably affect the dispersion characteristics of coupled-resonator optical waveguides (CROWs). We derive expressions for CROW dispersion and group delay for silicon-on-insulator microring CROWs, showing both theoretically and experimentally the band-to-band dependence of the bandwidth and group delay on the dispersion properties of the constituent single-mode silicon waveguide.

15.
Opt Lett ; 35(5): 784-6, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20195352

RESUMO

There is considerable research activity in multiresonator optical circuits in silicon photonics, e.g., for higher-order filters, advanced modulation format coding/decoding, or coupled-resonator optical waveguide delay lines. In diagnostics of such structures, it is usually not possible to measure each individual microring resonator without adding separate input and output waveguides to each resonator. We demonstrate a non-invasive diagnostic method of quantitative IR imaging, applied here to a series cascade of rings. The IR images contain information on the otherwise inaccessible individual through ports and the resonators themselves, providing an efficient means to obtain coupling, loss, and intensity-enhancement parameters for the individual rings.

16.
JACC Case Rep ; 2(6): 898-901, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34317377

RESUMO

Coronary thrombus aspiration was developed to remove thrombus, prevent distal embolization, and prepare the vessel for definitive intervention. However, its use is now limited by the risk of stroke. We describe a case where appropriate aspiration technique likely prevented central embolization of a coronary thrombus. (Level of Difficulty: Beginner.).

17.
J Cell Biol ; 164(6): 887-97, 2004 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-15024034

RESUMO

We have previously shown that the seemingly static paracrystalline actin core of hair cell stereocilia undergoes continuous turnover. Here, we used the same approach of transfecting hair cells with actin-green fluorescent protein (GFP) and espin-GFP to characterize the turnover process. Actin and espin are incorporated at the paracrystal tip and flow rearwards at the same rate. The flux rates (approximately 0.002-0.04 actin subunits s(-1)) were proportional to the stereocilia length so that the entire staircase stereocilia bundle was turned over synchronously. Cytochalasin D caused stereocilia to shorten at rates matching paracrystal turnover. Myosins VI and VIIa were localized alongside the actin paracrystal, whereas myosin XVa was observed at the tips at levels proportional to stereocilia lengths. Electron microscopy analysis of the abnormally short stereocilia in the shaker 2 mice did not show the characteristic tip density. We argue that actin renewal in the paracrystal follows a treadmill mechanism, which, together with the myosins, dynamically shapes the functional architecture of the stereocilia bundle.


Assuntos
Actinas/metabolismo , Cílios/metabolismo , Células Ciliadas Auditivas/citologia , Miosinas/metabolismo , Isoformas de Proteínas/metabolismo , Regeneração/fisiologia , Actinas/genética , Animais , Transporte Biológico/fisiologia , Células Cultivadas , Cílios/ultraestrutura , Citocalasina D/metabolismo , Citoesqueleto/metabolismo , Células Ciliadas Auditivas/metabolismo , Imuno-Histoquímica , Camundongos , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Modelos Biológicos , Proteínas Motores Moleculares/metabolismo , Inibidores da Síntese de Ácido Nucleico/metabolismo , Órgão Espiral/citologia , Subunidades Proteicas/metabolismo , Ratos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo
18.
Pediatr Res ; 65(6): 599-606, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19454962

RESUMO

Autism is a neurodevelopmental disorder of unknown etiology characterized by social and communication deficits and the presence of restricted interests/repetitive behaviors. Higher rates of epilepsy have long been reported, but prevalence estimates vary from as little as 5% to as much as 46%. This variation is probably the result of sample characteristics that increase epilepsy risk such as sample ascertainment, lower intelligence quotient (IQ), the inclusion of patients with nonidiopathic autism, age, and gender. However, critical review of the literature reveals that the rate in idiopathic cases with normal IQ is still significantly above the population risk suggesting that autism itself is associated with an increased risk of epilepsy. Recently, there has been interest in the occurrence of epileptiform electroencephalograms (EEGs) even in the absence of epilepsy. Rates as high as 60% have been reported and some investigators propose that these abnormalities may play a causal role in the autism phenotype. Although this phenomenon is still not well understood and risk factors have yet to be determined, the treatment implications are increasingly important. We review the recent literature to elucidate possible risk factors for both epilepsy and epileptiform EEGs. We then review existing data and discuss controversies surrounding treatment of EEG abnormalities.


Assuntos
Transtorno Autístico/fisiopatologia , Eletroencefalografia , Epilepsia/fisiopatologia , Idade de Início , Transtorno Autístico/genética , Transtorno Autístico/terapia , Comorbidade , Epilepsia/genética , Epilepsia/terapia , Humanos , Fatores de Risco
20.
Cell Death Discov ; 5: 58, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30701090

RESUMO

Sigma-2 receptors have been implicated in both tumor proliferation and neurodegenerative diseases. Recently the sigma-2 receptor was identified as transmembrane protein 97 (TMEM97). Progesterone receptor membrane component 1 (PGRMC1) was also recently reported to form a complex with TMEM97 and the low density lipoprotein (LDL) receptor, and this trimeric complex is responsible for the rapid internalization of LDL. Sigma-2 receptor ligands with various structures have been shown to induce cell death in cancer cells. In the current study, we examined the role of TMEM97 and PGRMC1 in mediating sigma-2 ligand-induced cell death. Cell viability and caspase-3 assays were performed in control, TMEM97 knockout (KO), PGRMC1 KO, and TMEM97/PGRMC1 double KO cell lines treated with several sigma-2 ligands. The data showed that knockout of TMEM97, PGRMC1, or both did not affect the concentrations of sigma-2 ligands that induced 50% of cell death (EC50), suggesting that cytotoxic effects of these compounds are not mediated by TMEM97 or PGRMC1. Sigma-1 receptor ligands, (+)-pentazocine and NE-100, did not block sigma-2 ligand cytotoxicity, suggesting that sigma-1 receptor was not responsible for sigma-2 ligand cytotoxicity. We also examined whether the alternative, residual binding site (RBS) of 1,3-Di-o-tolylguanidine (DTG) could be responsible for sigma-2 ligand cytotoxicity. Our data showed that the binding affinities (K i) of sigma-2 ligands on the DTG RBS did not correlate with the cytotoxicity potency (EC50) of these ligands, suggesting that the DTG RBS was not fully responsible for sigma-2 ligand cytotoxicity. In addition, we showed that knocking out TMEM97, PGRMC1, or both reduced the initial internalization rate of a sigma-2 fluorescent ligand, SW120. However, concentrations of internalized SW120 became identical later in the control and knockout cells. These data suggest that the initial internalization process of sigma-2 ligands does not appear to mediate the cell-killing effect of sigma-2 ligands. In summary, we have provided evidence that sigma-2 receptor/TMEM97 and PGRMC1 do not mediate sigma-2 ligand cytotoxicity. Our work will facilitate elucidating mechanisms of sigma-2 ligand cytotoxicity.

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