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1.
AJNR Am J Neuroradiol ; 44(8): 974-982, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37474265

RESUMO

BACKGROUND AND PURPOSE: Prior studies have found an association between calcification and the epileptogenicity of tubers in tuberous sclerosis complex. Quantitative susceptibility mapping is a novel tool sensitive to magnetic susceptibility alterations due to tissue calcification. We assessed the utility of quantitative susceptibility mapping in identifying putative epileptogenic tubers in tuberous sclerosis complex using stereoelectroencephalography data as ground truth. MATERIALS AND METHODS: We studied patients with tuberous sclerosis complex undergoing stereoelectroencephalography at a single center who had multiecho gradient-echo sequences available. Quantitative susceptibility mapping and R2* values were extracted for all tubers on the basis of manually drawn 3D ROIs using T1- and T2-FLAIR sequences. Characteristics of quantitative susceptibility mapping and R2* distributions from implanted tubers were compared using binary logistic generalized estimating equation models designed to identify ictal (involved in seizure onset) and interictal (persistent interictal epileptiform activity) tubers. These models were then applied to the unimplanted tubers to identify potential ictal and interictal tubers that were not sampled by stereoelectroencephalography. RESULTS: A total of 146 tubers were identified in 10 patients, 76 of which were sampled using stereoelectroencephalography. Increased kurtosis of the tuber quantitative susceptibility mapping values was associated with epileptogenicity (P = .04 for the ictal group and P = .005 for the interictal group) by the generalized estimating equation model. Both groups had poor sensitivity (35.0% and 44.1%, respectively) but high specificity (94.6% and 78.6%, respectively). CONCLUSIONS: Our finding of increased kurtosis of quantitative susceptibility mapping values (heavy-tailed distribution) was highly specific, suggesting that it may be a useful biomarker to identify putative epileptogenic tubers in tuberous sclerosis complex. This finding motivates the investigation of underlying tuber mineralization and other properties driving kurtosis changes in quantitative susceptibility mapping values.


Assuntos
Esclerose Tuberosa , Humanos , Projetos Piloto , Esclerose Tuberosa/complicações , Esclerose Tuberosa/diagnóstico por imagem , Imageamento por Ressonância Magnética , Eletroencefalografia
2.
Clin Lymphoma Myeloma Leuk ; 22(7): e526-e531, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35361554

RESUMO

Selinexor is a first in class selective inhibitor of nuclear export (SINE), blocks exportin 1 (XPO1), a protein transporter, that among other actions, shuttles cargo proteins such as tumor suppressor proteins (TSPs), the glucocorticoid receptor (GR), and oncoprotein messenger RNAs (mRNAs) across the nuclear membrane to cytoplasm. By blocking XPO1, selinexor facilitates nuclear preservation and activation of TSPs, and prevents mRNA translation of the oncoproteins leading to induction of apoptosis. The therapeutic value of selinexor in combination with dexamethasone has been successfully demonstrated in treating relapsed and/or refractory myeloma (RRMM), leading to the Food and Drug Administration (FDA) approval of selinexor in combination with dexamethasone in 2019 for the treatment of adult patients with RRMM who received at least 4 prior therapies and whose disease is refractory to at least 2 proteasome inhibitors, at least 2 immunomodulatory agents, and an anti-CD38 monoclonal antibody (mAb) - a pentarefractory myeloma. More recently, selinexor in combination with bortezomib and dexamethasone was approved by the FDA in December 2020, based on the BOSTON study among RRMM patients who had received at least one prior line of therapy. With more available safety and efficacy data supporting the increased interval between dosing of selinexor (and lesser cumulative weekly dosing) and schedule, contrary to the originally approved dose of 160 mg per week, the supportive care guidelines needed to be revisited. The current manuscript summarizes the supportive care solutions with weekly dosing of selinexor and identifies the ideal potential patient for selinexor treatment.


Assuntos
Mieloma Múltiplo , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Consenso , Dexametasona/farmacologia , Dexametasona/uso terapêutico , Humanos , Hidrazinas/farmacologia , Hidrazinas/uso terapêutico , Mieloma Múltiplo/patologia , Triazóis
3.
J Hosp Infect ; 117: 37-43, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34174379

RESUMO

The incidence of external ventricular drain (EVD) infections remains high. Chlorhexidine dressings have demonstrated efficacy in reducing infections associated with indwelling catheters at other body sites, although evidence for their use with EVDs is limited. The aim of this systematic review and meta-analysis was to evaluate the efficacy of chlorhexidine dressings in reducing EVD-associated cerebrospinal fluid infection (EVDAI). MEDLINE, EMBASE and the Cochrane library were queried for articles from inception. The primary outcome was the incidence of EVDAI. Secondary outcomes included device safety, microbiological outcomes and shunt-dependency. From 896 unique records, five studies were included of which four presented suitable data for quantitative analysis including three case series and one underpowered randomized controlled trial. There was a high risk of bias in all studies. A total of 880 patients were included with a mean age of 57.7 years (95% confidence interval (CI) 57.4-58.0 years). In primary outcome analysis, the chlorhexidine dressing group had a significantly lower incidence of EVDAI (1.7% vs 7.9%, risk difference (RD) = 0.07, 95% CI 0.00-0.13, P=0.04). In conclusion, chlorhexidine dressings may reduce the incidence of EVDAI but require future study in randomized trials to definitively determine efficacy.


Assuntos
Infecções Relacionadas a Cateter , Clorexidina , Bandagens , Infecções Relacionadas a Cateter/epidemiologia , Infecções Relacionadas a Cateter/prevenção & controle , Cateteres de Demora , Drenagem , Humanos , Pessoa de Meia-Idade
4.
J Health Econ ; 77: 102458, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33887659

RESUMO

For informal caregivers in certain demographic groups, the tradeoff between childcare and informal care may be as significant as the tradeoff between informal care and labor supply. We shed light on this tradeoff empirically, by combining detailed time use data with a natural experiment created by differential access to publicly funded kindergarten across households and states. We find a substantial elasticity between informal care supply and kindergarten access, especially for female carers. In fact, for women, kindergarten access appears to largely increase their care supply rather than labor supply.


Assuntos
Cuidado da Criança , Assistência ao Paciente , Cuidadores , Criança , Escolaridade , Características da Família , Feminino , Humanos
5.
Sci Adv ; 6(30): eaba3916, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32832664

RESUMO

Intrinsically disordered proteins (IDPs) can be degraded in a ubiquitin-independent process by the 20S proteasome. Decline in 20S activity characterizes neurodegenerative diseases. Here, we examine 20S degradation of IDP tau, a protein that aggregates into insoluble deposits in Alzheimer's disease. We show that cleavage of tau by the 20S proteasome is most efficient within the aggregation-prone repeat region of tau and generates both short, aggregation-deficient peptides and two long fragments containing residues 1 to 251 and 1 to 218. Phosphorylation of tau by the non-proline-directed Ca2+/calmodulin-dependent protein kinase II inhibits degradation by the 20S proteasome. Phosphorylation of tau by GSK3ß, a major proline-directed tau kinase, modulates tau degradation kinetics in a residue-specific manner. The study provides detailed insights into the degradation products of tau generated by the 20S proteasome, the residue specificity of degradation, single-residue degradation kinetics, and their regulation by posttranslational modification.

6.
Nat Commun ; 9(1): 4120, 2018 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-30297886

RESUMO

Genomic imprinting plays an important role in growth and development. Loss of imprinting (LOI) has been found in cancer, yet systematic studies are impeded by data-analytical challenges. We developed a methodology to detect monoallelically expressed loci without requiring genotyping data, and applied it on The Cancer Genome Atlas (TCGA, discovery) and Genotype-Tissue expression project (GTEx, validation) breast tissue RNA-seq data. Here, we report the identification of 30 putatively imprinted genes in breast. In breast cancer (TCGA), HM13 is featured by LOI and expression upregulation, which is linked to DNA demethylation. Other imprinted genes typically demonstrate lower expression in cancer, often associated with copy number variation and aberrant DNA methylation. Downregulation in cancer frequently leads to higher relative expression of the (imperfectly) silenced allele, yet this is not considered canonical LOI given the lack of (absolute) re-expression. In summary, our novel methodology highlights the massive deregulation of imprinting in breast cancer.


Assuntos
Neoplasias da Mama/genética , Mama/metabolismo , Regulação Neoplásica da Expressão Gênica , Impressão Genômica , Metilação de DNA , Feminino , Predisposição Genética para Doença/genética , Genótipo , Humanos
7.
Acta Neurol Scand ; 138(2): 137-142, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29532475

RESUMO

OBJECTIVES: Papilloedema is a clinical manifestation of chronically raised intracranial pressure (ICP), often seen in idiopathic intracranial hypertension (IIH). However, the extent of intracranial hypertension required to produce papilloedema is not known. We compare ICP values in IIH patients who developed papilloedema and those who did not. We aim to identify a pathological ICP threshold predictive of the development of papilloedema in IIH patients. MATERIALS AND METHODS: Single-centre cohort of IIH patients (2006-2016) who underwent 24-hour ICP monitoring (ICPM) and ophthalmology assessments, prior to intervention. Papilloedema was graded according to the Frisén scale. An unpaired t-test compared 24-hour ICPM between papilloedema and no-papilloedema groups. Fisher's exact test was used to determine predictive value of ICP. RESULTS: Thirty-six patients with IIH (35 F: 1M), mean age 32.5 ± 9.49 years (mean ± SD) were included. Patients with papilloedema had a mean median 24-hour ICP of 10.4 ± 5.32 mm Hg (n = 25), significantly higher than the group without papilloedema 6.31 ± 3.30 mm Hg (n = 11) (P < .05). The papilloedema group were exposed to higher pressures (10 mm Hg) for 30 minutes or more. Using 24-hour median ICP of 10 mm Hg as a minimum cut-off predictive value gives a specificity = 91%, sensitivity = 48%, PPV = 92% and NPV = 44% of detecting papilloedema. CONCLUSIONS: A 24-hour ICP of 10 mmHg or more is a good predictor for papilloedema and reflects a pathological threshold. The range varied widely suggesting papilloedema can occur at even lower pressures. These results are consistent with emerging evidence suggest that pathologically "high" 24 hours ICP is lower than previously quoted.


Assuntos
Papiledema/etiologia , Pseudotumor Cerebral/complicações , Adulto , Feminino , Humanos , Masculino , Monitorização Neurofisiológica , Papiledema/fisiopatologia , Pseudotumor Cerebral/fisiopatologia , Curva ROC , Valores de Referência , Estudos Retrospectivos , Adulto Jovem
8.
Leukemia ; 32(1): 120-130, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28642592

RESUMO

Multiple myeloma (MM) is an incurable malignancy of bone marrow plasma cells characterized by wide clinical and molecular heterogeneity. In this study we applied an integrative network biology approach to molecular and clinical data measured from 450 patients with newly diagnosed MM from the MMRF (Multiple Myeloma Research Foundation) CoMMpass study. A novel network model of myeloma (MMNet) was constructed, revealing complex molecular disease patterns and novel associations between clinical traits and genomic markers. Genomic alterations and groups of coexpressed genes correlate with disease stage, tumor clonality and early progression. We validated CDC42BPA and CLEC11A as novel regulators and candidate therapeutic targets of MMSET-related myeloma. We then used MMNet to discover novel genes associated with high-risk myeloma and identified a novel four-gene prognostic signature. We identified new patient classes defined by network features and enriched for clinically relevant genetic events, pathways and deregulated genes. Finally, we demonstrated the ability of deep sequencing techniques to detect relevant structural rearrangements, providing evidence that encourages wider use of such technologies in clinical practice. An integrative network analysis of CoMMpass data identified new insights into multiple myeloma disease biology and provided improved molecular features for diagnosing and stratifying patients, as well as additional molecular targets for therapeutic alternatives.


Assuntos
Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Medula Óssea/patologia , Linhagem Celular Tumoral , Progressão da Doença , Regulação Neoplásica da Expressão Gênica/fisiologia , Genoma/genética , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Prognóstico
9.
Soc Sci Med ; 196: 86-95, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29161641

RESUMO

High rates of home births in developing countries are often linked to high rates of newborn deaths, but there is considerable debate about how much of this is causal. This paper weighs in on this question by analyzing data on the timing of birth, health care utilization, and mortality for a sample of births between 2009-2014 in 7021 rural Nigerian households. First, we show that timing of birth is strongly linked to use of institutional care: women with a nighttime birth are significantly less likely to use a health facility because of the difficulties associated with accessing care at night. In turn, this is associated with a sharp increase in the rate of newborn mortality at night. Leveraging variation in household proximity to a health care facility that offers 24-h coverage, we show that this increase in mortality is plausibly due to lack of formal health care at the time of birth: infants born at night to households without a nearby health care facility that offers 24-h coverage, experience an increase in mortality equivalent to about 10 additional newborn deaths per 1000 live births. In contrast, when households have a nearby health facility that provides care at night, there is no detectable increase in mortality. These results suggest that well-designed policies to increase access to (and quality of) formal care at birth may lead to significant reductions in newborn deaths.


Assuntos
Parto Obstétrico/estatística & dados numéricos , Mortalidade Infantil/tendências , Adolescente , Adulto , Feminino , Acessibilidade aos Serviços de Saúde , Humanos , Lactente , Recém-Nascido , Masculino , Nigéria/epidemiologia , Gravidez , População Rural/estatística & dados numéricos , Fatores de Tempo , Adulto Jovem
12.
Rev Econ Stat ; 95(3)2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24357882

RESUMO

A key prediction of dynamic labor demand models is that firing restrictions attenuate firms' employment responses to economic fluctuations. We provide the first direct test of this prediction using data from India. We exploit the fact that rainfall fluctuations, through their effects on agricultural productivity, generate variation in local demand within districts over time. Consistent with the theory, we find that industrial employment is more sensitive to shocks where labor regulation is less restrictive. Our results are robust to controlling for endogenous firm placement and vary across factory size in a pattern consistent with institutional features of Indian labor law.

13.
Mol Cell Biol ; 19(7): 5143-54, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10373563

RESUMO

Mitogen-activated protein (MAP) kinases phosphorylate the estrogen receptor and activate transcription from estrogen receptor-regulated genes. Here we examine potential interactions between the MAP kinase cascade and androgen receptor-mediated gene regulation. Specifically, we have studied the biological effects of mitogen-activated protein kinase kinase kinase 1 (MEKK1) expression in prostate cancer cells. Our findings demonstrate that expression of constitutively active MEKK1 induces apoptosis in androgen receptor-positive but not in androgen receptor-negative prostate cancer cells. Reconstitution of the androgen receptor signaling pathway in androgen receptor-negative prostate cancer cells restores MEKK1-induced apoptosis. MEKK1 also stimulates the transcriptional activity of the androgen receptor in the presence or absence of ligand, whereas a dominant negative mutant of MEKK1 impairs activation of the androgen receptor by androgen. These studies demonstrate an unanticipated link between MEKK1 and hormone receptor signaling and have implications for the molecular basis of hormone-independent prostate cancer growth.


Assuntos
Apoptose , Regulação Neoplásica da Expressão Gênica , MAP Quinase Quinase Quinase 1 , Proteínas Quinases Ativadas por Mitógeno , Neoplasias da Próstata/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Receptores Androgênicos/metabolismo , Animais , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Linhagem Celular , Ativação Enzimática , Regulação da Expressão Gênica , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno , Masculino , Camundongos , Camundongos SCID , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/genética , Proteínas Serina-Treonina Quinases/genética , Transdução de Sinais , Transcrição Gênica , Células Tumorais Cultivadas
18.
20.
Science ; 175(4027): 1192-4, 1972 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-17794182
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