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1.
PLoS Genet ; 19(5): e1010729, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37155670

RESUMO

Repressive KRAB domain-containing zinc-finger proteins (KRAB-ZFPs) are abundant in mammalian genomes and contribute both to the silencing of transposable elements (TEs) and to the regulation of developmental stage- and cell type-specific gene expression. Here we describe studies of zinc finger protein 92 (Zfp92), an X-linked KRAB-ZFP that is highly expressed in pancreatic islets of adult mice, by analyzing global Zfp92 knockout (KO) mice. Physiological, transcriptomic and genome-wide chromatin binding studies indicate that the principal function of ZFP92 in mice is to bind to and suppress the activity of B1/Alu type of SINE elements and modulate the activity of surrounding genomic entities. Deletion of Zfp92 leads to changes in expression of select LINE and LTR retroelements and genes located in the vicinity of ZFP92-bound chromatin. The absence of Zfp92 leads to altered expression of specific genes in islets, adipose and muscle that result in modest sex-specific alterations in blood glucose homeostasis, body mass and fat accumulation. In islets, Zfp92 influences blood glucose concentration in postnatal mice via transcriptional effects on Mafb, whereas in adipose and muscle, it regulates Acacb, a rate-limiting enzyme in fatty acid metabolism. In the absence of Zfp92, a novel TE-Capn11 fusion transcript is overexpressed in islets and several other tissues due to de-repression of an IAPez TE adjacent to ZFP92-bound SINE elements in intron 3 of the Capn11 gene. Together, these studies show that ZFP92 functions both to repress specific TEs and to regulate the transcription of specific genes in discrete tissues.


Assuntos
Elementos de DNA Transponíveis , Ilhotas Pancreáticas , Animais , Feminino , Masculino , Camundongos , Glicemia , Cromatina , Ilhotas Pancreáticas/metabolismo , Mamíferos/genética , Proteínas Repressoras/genética , Retroelementos/genética , Dedos de Zinco/genética
2.
PLoS Genet ; 16(7): e1008901, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32645003

RESUMO

The RNA exosome is an evolutionarily-conserved ribonuclease complex critically important for precise processing and/or complete degradation of a variety of cellular RNAs. The recent discovery that mutations in genes encoding structural RNA exosome subunits cause tissue-specific diseases makes defining the role of this complex within specific tissues critically important. Mutations in the RNA exosome component 3 (EXOSC3) gene cause Pontocerebellar Hypoplasia Type 1b (PCH1b), an autosomal recessive neurologic disorder. The majority of disease-linked mutations are missense mutations that alter evolutionarily-conserved regions of EXOSC3. The tissue-specific defects caused by these amino acid changes in EXOSC3 are challenging to understand based on current models of RNA exosome function with only limited analysis of the complex in any multicellular model in vivo. The goal of this study is to provide insight into how mutations in EXOSC3 impact the function of the RNA exosome. To assess the tissue-specific roles and requirements for the Drosophila ortholog of EXOSC3 termed Rrp40, we utilized tissue-specific RNAi drivers. Depletion of Rrp40 in different tissues reveals a general requirement for Rrp40 in the development of many tissues including the brain, but also highlight an age-dependent requirement for Rrp40 in neurons. To assess the functional consequences of the specific amino acid substitutions in EXOSC3 that cause PCH1b, we used CRISPR/Cas9 gene editing technology to generate flies that model this RNA exosome-linked disease. These flies show reduced viability; however, the surviving animals exhibit a spectrum of behavioral and morphological phenotypes. RNA-seq analysis of these Drosophila Rrp40 mutants reveals increases in the steady-state levels of specific mRNAs and ncRNAs, some of which are central to neuronal function. In particular, Arc1 mRNA, which encodes a key regulator of synaptic plasticity, is increased in the Drosophila Rrp40 mutants. Taken together, this study defines a requirement for the RNA exosome in specific tissues/cell types and provides insight into how defects in RNA exosome function caused by specific amino acid substitutions that occur in PCH1b can contribute to neuronal dysfunction.


Assuntos
Doenças Cerebelares/genética , Proteínas do Citoesqueleto/genética , Drosophila melanogaster/genética , Complexo Multienzimático de Ribonucleases do Exossomo/genética , Proteínas do Tecido Nervoso/genética , Neurônios/metabolismo , Proteínas de Ligação a RNA/genética , Substituição de Aminoácidos/genética , Animais , Sistemas CRISPR-Cas/genética , Doenças Cerebelares/patologia , Cerebelo/metabolismo , Cerebelo/patologia , Modelos Animais de Doenças , Exossomos/genética , Humanos , Mutação/genética , Neurônios/patologia , RNA/genética
3.
Exp Eye Res ; 202: 108370, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33264655

RESUMO

Cre-mediated modulation of gene function in the murine retinal pigment epithelium (RPE) has been widely used, but current postnatal RPE-selective Cre driver lines suffer from limited recombination efficiency and/or ectopic or mosaic expression. We sought to generate a transgenic mouse line with consistently efficient RPE-selective Cre activity that could be temporally regulated. We used ϕC31 integrase to insert a DNA construct encoding a human BEST1 promoter fragment driving a Cre recombinase estrogen receptor fusion (BEST1-CreERT2) at the Rosa26 locus of C57BL/6J mice. Rosa26BEST1-CreERT2 mice were bred with a tdTomato reporter line and to mice with a Cre-conditional allele of Tfam. 4-hydroxytamoxifen or vehicle was delivered by four consecutive daily intraperitoneal injections. TdTomato was robustly expressed in the RPE of mice of both sexes for inductions beginning at P14 (males 90.7 ± 4.5%, females 84.7 ± 3.2%) and at 7 weeks (males 84.3 ± 7.0%, females 82 ± 3.6%). <0.6% of Muller glia also expressed tdTomato, but no tdTomato fluorescence was observed in other ocular cells or in multiple non-ocular tissues, with the exception of sparse foci in the testis. No evidence of retinal toxicity was observed in mice homozygous for the transgene induced beginning at P14 and assessed at 7-10 months. RPE-selective ablation of Tfam beginning at P14 led to reduced retinal thickness at 8 months of age and diminished retinal electrical responses at 12 months, as expected. These findings demonstrate that we have generated a mouse line with consistently efficient, tamoxifen-mediated postnatal induction of Cre recombination in the RPE and a small fraction of Muller glia. This line should be useful for temporally regulated modulation of gene function in the murine RPE.


Assuntos
Regulação da Expressão Gênica , Integrases/genética , Degeneração Macular/genética , Epitélio Pigmentado da Retina/metabolismo , Animais , Modelos Animais de Doenças , Eletrorretinografia , Integrases/biossíntese , Degeneração Macular/metabolismo , Degeneração Macular/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , RNA/genética , RNA/metabolismo , Epitélio Pigmentado da Retina/patologia , Tomografia de Coerência Óptica
4.
Epilepsia ; 62(1): 74-84, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33236777

RESUMO

OBJECTIVE: Intracranial electrographic localization of the seizure onset zone (SOZ) can guide surgical approaches for medically refractory epilepsy patients, especially when the presurgical workup is discordant or functional cortical mapping is required. Minimally invasive stereotactic placement of depth electrodes, stereoelectroencephalography (SEEG), has garnered increasing use, but limited data exist to evaluate its postoperative outcomes in the context of the contemporaneous availability of both SEEG and subdural electrode (SDE) monitoring. We aimed to assess the patient experience, surgical intervention, and seizure outcomes associated with these two epileptic focus mapping techniques during a period of rapid adoption of neuromodulatory and ablative epilepsy treatments. METHODS: We retrospectively reviewed 66 consecutive adult intracranial electrode monitoring cases at our institution between 2014 and 2017. Monitoring was performed with either SEEG (n = 47) or SDEs (n = 19). RESULTS: Both groups had high rates of SOZ identification (SEEG 91.5%, SDE 88.2%, P = .69). The majority of patients achieved Engel class I (SEEG 29.3%, SDE 35.3%) or II outcomes (SEEG 31.7%, SDE 29.4%) after epilepsy surgery, with no significant difference between groups (P = .79). SEEG patients reported lower median pain scores (P = .03) and required less narcotic pain medication (median = 94.5 vs 594.6 milligram morphine equivalents, P = .0003). Both groups had low rates of symptomatic hemorrhage (SEEG 0%, SDE 5.3%, P = .11). On multivariate logistic regression, undergoing resection or ablation (vs responsive neurostimulation/vagus nerve stimulation) was the only significant independent predictor of a favorable outcome (adjusted odds ratio = 25.4, 95% confidence interval = 3.48-185.7, P = .001). SIGNIFICANCE: Although both SEEG and SDE monitoring result in favorable seizure control, SEEG has the advantage of superior pain control, decreased narcotic usage, and lack of routine need for intensive care unit stay. Despite a heterogenous collection of epileptic semiologies, seizure outcome was associated with the therapeutic surgical modality and not the intracranial monitoring technique. The potential for an improved postoperative experience makes SEEG a promising method for intracranial electrode monitoring.


Assuntos
Mapeamento Encefálico/métodos , Terapia por Estimulação Elétrica , Eletrocorticografia/métodos , Epilepsia/fisiopatologia , Terapia a Laser , Procedimentos Neurocirúrgicos , Adulto , Eletroencefalografia , Epilepsia/diagnóstico , Epilepsia/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Implantação de Prótese/métodos , Estudos Retrospectivos , Técnicas Estereotáxicas , Espaço Subdural , Resultado do Tratamento , Estimulação do Nervo Vago , Adulto Jovem
5.
J Gen Intern Med ; 35(1): 291-297, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31720966

RESUMO

BACKGROUND: The morbidity and mortality associated with opioid and benzodiazepine co-prescription is a pressing national concern. Little is known about patterns of opioid and benzodiazepine use in patients with acute low back pain or lower extremity pain. OBJECTIVE: To characterize patterns of opioid and benzodiazepine prescribing among opioid-naïve, newly diagnosed low back pain (LBP) or lower extremity pain (LEP) patients and to investigate the relationship between benzodiazepine prescribing and long-term opioid use. DESIGN/SETTING: We performed a retrospective analysis of a commercial database containing claims for more than 75 million enrollees in the USA. PARTICIPANTS: Participants were adult patients newly diagnosed with LBP or LEP between 2008 and 2015 who did not have a red flag diagnosis, had not received an opioid prescription in the 6 months prior to diagnosis, and had 12 months of continuous enrollment after diagnosis. MAIN OUTCOMES AND MEASURES: Among patients receiving at least one opioid prescription within 12 months of diagnosis, we defined discrete patterns of benzodiazepine prescribing-continued use, new use, stopped use, and never use. We tested the association of these prescription patterns with long-term opioid use, defined as six or more fills within 12 months. RESULTS: We identified 2,497,653 opioid-naïve patients with newly diagnosed LBP or LEP. Between 2008 and 2015, 31.9% and 11.5% of these patients received opioid and benzodiazepine prescriptions, respectively, within 12 months of diagnosis. Rates of opioid prescription decreased from 34.8% in 2008 to 27.0% in 2015 (P < 0.001); however, prescribing of benzodiazepines only decreased from 11.6% in 2008 to 10.8% in 2015. Patients with continued or new benzodiazepine use consistently used more opioids than patients who never used or stopped using benzodiazepines during the study period (one-way ANOVA, P < 0.001). For patients with continued and new benzodiazepine use, the odds ratio of long-term opioid use compared with those never prescribed a benzodiazepine was 2.99 (95% CI, 2.89-3.08) and 2.68 (95% CI, 2.62-2.75), respectively. LIMITATIONS: This study used administrative claims analyses, which rely on accuracy and completeness of diagnostic, procedural, and prescription codes. CONCLUSION: Overall opioid prescribing for low back pain or lower extremity pain decreased substantially during the study period, indicating a shift in management within the medical community. Rates of benzodiazepine prescribing, however, remained at approximately 11%. Concurrent prescriptions of benzodiazepines and opioids after LBP or LEP diagnosis were associated with increased risk of long-term opioid use.


Assuntos
Analgésicos Opioides , Benzodiazepinas , Adulto , Analgésicos Opioides/uso terapêutico , Benzodiazepinas/uso terapêutico , Humanos , Extremidade Inferior , Padrões de Prática Médica , Estudos Retrospectivos
6.
Pediatr Blood Cancer ; 67(3): e28104, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31802628

RESUMO

BACKGROUND AND PURPOSE: Children with Langerhans cell histiocytosis (LCH) may develop a wide array of neurological symptoms, but associated cerebral physiologic changes are poorly understood. We examined cerebral hemodynamic properties of pediatric LCH using arterial spin-labeling (ASL) perfusion magnetic resonance imaging (MRI). MATERIALS AND METHODS: A retrospective study was performed in 23 children with biopsy-proven LCH. Analysis was performed on routine brain MRI obtained before or after therapy. Region of interest (ROI) methodology was used to determine ASL cerebral blood flow (CBF) (mL/100 g/min) in the following bilateral regions: angular gyrus, anterior prefrontal cortex, orbitofrontal cortex, dorsal anterior cingulate cortex, and hippocampus. Quantile (median) regression was performed for each ROI location. CBF patterns were compared between pre- and posttreatment LCH patients as well as with age-matched healthy controls. RESULTS: Significantly reduced CBF was seen in posttreatment children with LCH compared to age-matched controls in angular gyrus (P = .046), anterior prefrontal cortex (P = .039), and dorsal anterior cingulate cortex (P = .023). Further analysis revealed dominant perfusion abnormalities in the right hemisphere. No significant perfusion differences were observed in the hippocampus or orbitofrontal cortex. CONCLUSION: Perfusion in specific cerebral regions may be consistently reduced in children with LCH, and may represent effects of underlying disease physiology and/or sequelae of chemotherapy. Studies that combine a formal cognitive assessment and hemodynamic data may further provide insight into perfusion deficits associated with the disease and the potential neurotoxic effects in children treated by chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Artérias Cerebrais/patologia , Circulação Cerebrovascular/efeitos dos fármacos , Histiocitose de Células de Langerhans/tratamento farmacológico , Neuroimagem/métodos , Estudos de Casos e Controles , Artérias Cerebrais/efeitos dos fármacos , Criança , Pré-Escolar , Feminino , Seguimentos , Histiocitose de Células de Langerhans/patologia , Humanos , Lactente , Angiografia por Ressonância Magnética , Masculino , Perfusão , Prognóstico , Estudos Retrospectivos
7.
Epilepsy Behav ; 104(Pt A): 106905, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32028127

RESUMO

BACKGROUND: For patients with medically refractory epilepsy, intracranial electrode monitoring can help identify epileptogenic foci. Despite the increasing utilization of stereoelectroencephalography (SEEG), the relative risks or benefits associated with the technique when compared with the traditional subdural electrode monitoring (SDE) remain unclear, especially in the pediatric population. Our aim was to compare the outcomes of pediatric patients who received intracranial monitoring with SEEG or SDE (grids and strips). METHODS: We retrospectively studied 38 consecutive pediatric intracranial electrode monitoring cases performed at our institution from 2014 to 2017. Medical/surgical history and operative/postoperative records were reviewed. We also compared direct inpatient hospital costs associated with the two procedures. RESULTS: Stereoelectroencephalography and SDE cohorts both showed high likelihood of identifying epileptogenic zones (SEEG: 90.9%, SDE: 87.5%). Compared with SDE, SEEG patients had a significantly shorter operative time (118.7 versus 233.4 min, P < .001) and length of stay (6.2 versus 12.3 days, P < .001), including days spent in the intensive care unit (ICU; 1.4 versus 5.4 days, P < .001). Stereoelectroencephalography patients tended to report lower pain scores and used significantly less narcotic pain medications (54.2 versus 197.3 mg morphine equivalents, P = .005). No complications were observed. Stereoelectroencephalography and SDE cohorts had comparable inpatient hospital costs (P = .47). CONCLUSION: In comparison with subdural electrode placement, SEEG results in a similarly favorable clinical outcome, but with reduced operative time, decreased narcotic usage, and superior pain control without requiring significantly higher costs. The potential for an improved postoperative intracranial electrode monitoring experience makes SEEG especially suitable for pediatric patients.


Assuntos
Epilepsia Resistente a Medicamentos/cirurgia , Eletrodos Implantados , Eletroencefalografia/métodos , Cuidados Pós-Operatórios/métodos , Técnicas Estereotáxicas , Adolescente , Criança , Custos e Análise de Custo/métodos , Epilepsia Resistente a Medicamentos/fisiopatologia , Eletrodos Implantados/tendências , Eletroencefalografia/tendências , Feminino , Humanos , Unidades de Terapia Intensiva/tendências , Masculino , Morfina/administração & dosagem , Cuidados Pós-Operatórios/tendências , Estudos Retrospectivos , Técnicas Estereotáxicas/tendências , Resultado do Tratamento
8.
Stereotact Funct Neurosurg ; 98(1): 1-7, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32062664

RESUMO

INTRODUCTION: Stereoelectroencephalography (SEEG) is a powerful intracranial diagnostic tool that requires accurate imaging for proper electrode trajectory planning to ensure efficacy and maximize patient safety. Computed tomography (CT) angiography and digital subtraction angiography are commonly used, but recent developments in magnetic resonance angiography allow for high-resolution vascular visualization without added risks of radiation. We report on the accuracy of electrode placement under robotic assistance planning utilizing a novel high-resolution magnetic resonance imaging (MRI)-based imaging modality. METHODS: Sixteen pediatric patients between February 2014 and October 2017 underwent SEEG exploration for epileptogenic zone localization. A gadolinium-enhanced 3D T1-weighted spoiled gradient recalled echo sequence with minimum echo time and repetition time was applied for background parenchymal suppression and vascular enhancement. Electrode placement accuracy was determined by analyzing postoperative CT scans laid over preoperative virtual electrode trajectory paths. Entry point, target point, and closest vessel intersection were measured. RESULTS: For any intersection along the trajectory path, 57 intersected vessels were measured. The mean diameter of an intersected vessel was 1.0343 ± 0.1721 mm, and 21.05% of intersections involved superficial vessels. There were 157 overall intersection + near-miss events. The mean diameter for an involved vessel was 1.0236 ± 0.0928 mm, and superficial vessels were involved in 20.13%. Looking only at final electrode target, 3 intersection events were observed. The mean diameter of an intersected vessel was 1.0125 ± 0.2227 mm. For intersection + near-miss events, 24 were measured. An involved vessel's mean diameter was 1.1028 ± 0.2634 mm. For non-entry point intersections, 45 intersected vessels were measured. The mean diameter for intersected vessels was 0.9526 ± 0.0689 mm. For non-entry point intersections + near misses, 126 events were observed. The mean diameter for involved vessels was 0.9826 ± 0.1008 mm. CONCLUSION: We believe this novel sequence allows better identification of superficial and deeper subcortical vessels compared to conventional T1-weighted gadolinium-enhanced MRI.


Assuntos
Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Eletroencefalografia/métodos , Imageamento por Ressonância Magnética/métodos , Cuidados Pré-Operatórios/métodos , Técnicas Estereotáxicas , Tomografia Computadorizada por Raios X/métodos , Adolescente , Criança , Epilepsia Resistente a Medicamentos/cirurgia , Eletrodos Implantados , Feminino , Humanos , Angiografia por Ressonância Magnética/métodos , Masculino
9.
Neurosurg Focus ; 45(6): E16, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30544324

RESUMO

The impact of traumatic brain injury (TBI) has been demonstrated in various studies with respect to prevalence, morbidity, and mortality data. Many of the patients burdened with long-term sequelae of TBI are veterans. Although fewer in number, female veterans with TBI have been suggested to suffer from unique physical, mental, and social challenges. However, there remains a significant knowledge gap in the sex differences in TBI. Increased female representation in the military heralds an increased risk of TBI for female soldiers, and medical professionals must be prepared to address the unique health challenges in the face of changing demographics among the veteran TBI population. In this review, the authors aimed to present the current understanding of sex differences in TBI in the veteran population and suggest directions for future investigations.


Assuntos
Lesões Encefálicas Traumáticas/epidemiologia , Militares/estatística & dados numéricos , Neurocirurgia , Fatores Sexuais , Concussão Encefálica/epidemiologia , Lesões Encefálicas/epidemiologia , Lesões Encefálicas Traumáticas/cirurgia , Feminino , Humanos , Masculino , Prevalência , Veteranos
10.
Neurosurg Focus ; 45(3): E7, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30173607

RESUMO

Stereoelectroencephalography (SEEG) is an intracranial diagnostic measure that has grown in popularity in the United States as outcomes data have demonstrated its benefits and safety. The main uses of SEEG include 1) exploration of deep cortical/sulcal structures; 2) bilateral recordings; and 3) 3D mapping of epileptogenic zones. While SEEG has gradually been accepted for treatment in adults, there is less consensus on its utility in children. In this literature review, the authors seek to describe the current state of SEEG with a focus on the more recent technology-enabled surgical techniques and demonstrate its efficacy in the pediatric epilepsy population.


Assuntos
Eletroencefalografia/métodos , Epilepsia/diagnóstico , Epilepsia/fisiopatologia , Técnicas Estereotáxicas , Criança , Eletrodos Implantados/tendências , Eletroencefalografia/tendências , Epilepsia/cirurgia , Humanos , Técnicas Estereotáxicas/tendências
11.
J Neurosci ; 36(36): 9490-504, 2016 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-27605622

RESUMO

UNLABELLED: Reconsolidation updating is a form of memory modification in which an existing memory can become destabilized upon retrieval and subsequently be modified via protein-synthesis-dependent reconsolidation. However, not all memories appear to destabilize upon retrieval and thus are not modifiable via reconsolidation updating approaches and the neurobiological basis for this remains poorly understood. Here, we report that auditory fear memories created with 10 tone-shock pairings are resistant to retrieval-dependent memory destabilization and are associated with an increase in the synaptic GluN2A/GluN2B ratio in neurons of the basal and lateral amygdala (BLA) compared with weaker fear memories created via one or three tone-shock pairings. To increase the GluN2A/GluN2B ratio after learning, we generated a line of mice that expresses an inducible and doxycycline-dependent GFP-GluN2A transgene specifically in α-CaMKII-positive neurons. Our findings indicate that increasing the GluN2A/GluN2B ratio in BLA α-CaMKII-positive neurons after a weak fear memory has consolidated inhibits retrieval-dependent memory destabilization and modification of the fear memory trace. This was associated with a reduction in retrieval-dependent AMPA receptor trafficking, as evidenced by a reduction in retrieval-dependent phosphorylation of GluR1 at serine-845. In addition, we determined that increasing the GluN2A/GluN2B ratio before fear learning significantly impaired long term memory consolidation, whereas short-term memory remained unaltered. An increase in the GluN2A/GluN2B ratio after fear learning had no influence on fear extinction or expression. Our results underscore the importance of NMDAR subunit composition for memory destabilization and suggest a mechanism for why some memories are resistant to modification. SIGNIFICANCE STATEMENT: Memory modification using reconsolidation updating is being examined as one of the potential treatment approaches for attenuating maladaptive memories associated with emotional disorders. However, studies have shown that, whereas weak memories can be modified using reconsolidation updating, strong memories can be resistant to this approach. Therefore, treatments targeting the reconsolidation process are unlikely to be clinically effective unless methods are devised to enhance retrieval-dependent memory destabilization. Currently, little is known about the cellular and molecular events that influence the induction of reconsolidation updating. Here, we determined that an increase in the GluN2A/GluN2B ratio interferes with retrieval-dependent memory destabilization and inhibits the initiation of reconsolidation updating.


Assuntos
Tonsila do Cerebelo/metabolismo , Medo/psicologia , Memória/fisiologia , Receptores de N-Metil-D-Aspartato/metabolismo , Estimulação Acústica , Análise de Variância , Animais , Anisomicina/farmacologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Proteína 4 Homóloga a Disks-Large , Fármacos Atuantes sobre Aminoácidos Excitatórios/farmacologia , Extinção Psicológica/efeitos dos fármacos , Feminino , Guanilato Quinases/metabolismo , Masculino , Proteínas de Membrana/metabolismo , Rememoração Mental/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Inibidores da Síntese de Proteínas/farmacologia , Receptores de N-Metil-D-Aspartato/genética
12.
Clin Gastroenterol Hepatol ; 14(6): 887-895.e1, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26820401

RESUMO

BACKGROUND & AIMS: Hepatitis B virus (HBV) is the most common cause of hepatocellular carcinoma (HCC) worldwide. Unlike other liver diseases, HBV can cause HCC in the absence of cirrhosis. We investigated whether features of HCC in patients with HBV infection without cirrhosis and survival times differ from those of patients who develop HCC after cirrhosis. METHODS: We performed a retrospective cohort study of 487 consecutive cases of HBV-related HCC who were seen from 2000 through 2014 at a tertiary care center. Laboratory values, imaging results, and treatment information were obtained from subjects' medical records. Symptoms of HCC included weight loss, abdominal pain, or new hepatic decompensation. The primary outcome was overall survival, which was categorized as short-term survival (up to 3 years after the diagnosis of HCC) or long-term survival (3-10 years after diagnosis). RESULTS: The mean tumor size at diagnosis was significantly larger in patients without cirrhosis (6.4 ± 4.3 cm) than in patients with cirrhosis (5.0 ± 3.8 cm) (P = .0009). A significantly larger proportion of patients without cirrhosis had symptoms at diagnosis (43.8% vs 35.4% in patients without cirrhosis, P = .09). A significantly higher proportion of patients without cirrhosis survived for the long-term (P = .003), but there was no significant difference between groups in short-term survival (P = .37). Notably, the same proportions of asymptomatic patients with and without cirrhosis survived for the short-term (64.3% vs 64.2%, P = .73), but a lower proportion of asymptomatic patients with cirrhosis survived for the long-term (P = .015). In multivariate Cox regression analysis, cirrhosis was an independent predictor of death in 3-10 years (hazard ratio, 3.76; P = .003) but not in less than 3 years (P = .48). Symptoms at diagnosis predicted death within 3 years (hazard ratio, 1.76; P =.006) but not in 3-10 years (P = .15). CONCLUSIONS: Patients with HBV infection and HCC without cirrhosis present with larger tumors, and a larger percentage have symptoms of cancer than patients with cirrhosis. This may indicate that HCC surveillance is less than optimal for patients with HBV infection without cirrhosis. Despite this suboptimal surveillance, patients without cirrhosis have higher long-term survival than those with cirrhosis, especially when asymptomatic at diagnosis.


Assuntos
Carcinoma Hepatocelular/epidemiologia , Hepatite B Crônica/complicações , Cirrose Hepática/complicações , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/mortalidade , Adulto , Idoso , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida
13.
Dig Dis Sci ; 61(2): 618-25, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26660679

RESUMO

BACKGROUND AND AIMS: Chronic hepatitis B (CHB) is a major cause of cirrhosis and end-stage liver disease. Not all patients with CHB require antiviral treatment but long-term monitoring is critical to identify patients who would benefit from antiviral therapy. CHB patients followed in various clinical settings may differ in disease characteristics and rates of treatment eligibility in long-term follow-up. METHODS: We conducted a retrospective cohort study of 359 consecutive treatment-naive, treatment-ineligible CHB patients (228 from community GI clinics; 73 from university hepatology clinic; 58 from primary care clinic). Primary end points were the proportion of patients meeting eligibility criteria in follow-up, and the eligibility comparison among patients in various clinical settings. Univariate and multivariate Cox's proportional hazard models were used to calculate hazard ratios to identify predictors of treatment eligibility in follow-up. RESULTS: While the majority of patients remained treatment ineligible by guideline recommendations, a sizeable proportion (23 %, 95 % CI 18-27 %) of patients subsequently met treatment eligibility in study follow-up. Reasons for meeting US Panel treatment eligibility on multivariate analysis included baseline ALT ≥ ULN (HR 1.91, p = 0.03) and baseline HBV DNA ≥ 2000 IU/mL (HR 2.6, p = 0.001). Practice setting was not a predictor. CONCLUSIONS: A significant number of patients with CHB (23 %) who were not initially treatment eligible later met treatment criteria in longer-term follow-up. Significant independent predictors of treatment eligibility included a baseline ALT ≥ ULN and elevated HBV DNA (≥2000 IU/mL for US Panel eligibility and ≥20,000 IU/mL for AASLD eligibility). This study underscores the importance of long-term follow-up for patients with CHB.


Assuntos
Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Adulto , Alanina Transaminase/sangue , Estudos de Coortes , DNA Viral/sangue , Feminino , Antígenos E da Hepatite B , Vírus da Hepatite B/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Estados Unidos
14.
J Clin Gastroenterol ; 49(2): 158-64, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24804988

RESUMO

GOALS: We aimed to determine the incidence and predictors of recurrent hepatocellular carcinoma (HCC) after partial hepatectomy. BACKGROUND: Liver transplantation is the preferred treatment for selected patients with HCC, but access to donor organs is limited. Partial hepatectomy is another accepted treatment option; however, postoperative recurrence is frequently observed. METHODS: This is a retrospective cohort study of 107 consecutive patients who underwent partial hepatectomy for HCC between January 1993 and February 2011 at a US University Medical Center. Study endpoints were recurrent HCC, death, loss to follow-up, or last visit without HCC. RESULTS: The study cohort was 78% male with a median age of 61 years and 59% Asians. A total of 50 patients developed recurrent HCC (46.7%) after a median follow-up of 12 (1 to 69) months postresection. Recurrent HCC was significantly higher in patients with left-sided resection (41% at year 1, 54% at year 2, 62% at year 3, 81% at year 4, and 90% at year 5) compared with right-sided resection (18% at year 1, 34% at year 2, 36% at year 3, 44% at year 4, and 72% at year 5). In multivariate Cox proportional hazards model also inclusive of anatomic resection and TNM stage 3/4, left-sided resection was significantly associated with increased HCC recurrence (hazard ratio, 2.13; P=0.02; 95% confidence interval, 1.08-4.2) compared with right-sided resection. CONCLUSIONS: HCC recurrence rate is higher among those undergoing left-sided resection: 54% at year 2 and 81% at year 4. Liver transplantation should be considered in patients who are at high risk for recurrence.


Assuntos
Carcinoma Hepatocelular/cirurgia , Hepatectomia/métodos , Neoplasias Hepáticas/cirurgia , Recidiva Local de Neoplasia , Centros Médicos Acadêmicos , Adulto , Idoso , Idoso de 80 Anos ou mais , California , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Distribuição de Qui-Quadrado , Feminino , Hepatectomia/efeitos adversos , Hepatectomia/mortalidade , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
15.
Dig Dis Sci ; 59(9): 2091-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25060778

RESUMO

BACKGROUND AND AIMS: Data on usage of antiviral therapy and application of chronic hepatitis B (CHB) management guidelines in different settings are limited. Our goal is to evaluate the proportion of treatment-eligible patients by 6-month follow-up and treatment rate among eligible patients by 12-month follow-up in diverse settings. METHODS: In this retrospective cohort study, 1,976 treatment-naïve CHB patients were categorized as primary care physician (PCP) group if seen by community PCP (n = 329), gastroenterology (GI) group if seen by community gastroenterologists (n = 1,268), and hepatology group if seen by university hepatologists (n = 379). Treatment eligibility was based on the US Panel 2008 and American Association for the Study of Liver Diseases (AASLD) 2009 guidelines. RESULTS: All groups had similar age, gender, and ethnic distribution. GI and hepatology groups had similar treatment eligibility rates by US Panel (53-54 %) and AASLD guidelines (24-25 %). However, treatment rate was significantly higher in hepatology compared to GI group by the US Panel guideline (59 vs. 45 %, P = 0.001). PCP group had the lowest eligibility and treatment rates by both guidelines. Common reasons for non-treatment were perceived "normal" alanine aminotransferase, desire for further observation, and patient refusal. Male gender, age >50, and subspecialty care predicted treatment initiation in treatment-eligible patients. CONCLUSIONS: Less than half of treatment-eligible patients at primary care clinics received treatment. Community gastroenterology and university liver clinics treated about one-half to two-thirds of eligible patients. Patient and provider education should highlight treatment benefits and the new alanine aminotransferase upper limit of normal.


Assuntos
Antivirais/uso terapêutico , Gastroenterologia/estatística & dados numéricos , Fidelidade a Diretrizes/estatística & dados numéricos , Hepatite B Crônica/tratamento farmacológico , Atenção Primária à Saúde/estatística & dados numéricos , Centros Médicos Acadêmicos/normas , Centros Médicos Acadêmicos/estatística & dados numéricos , Adulto , Fatores Etários , Alanina Transaminase/sangue , Serviços de Saúde Comunitária/normas , Serviços de Saúde Comunitária/estatística & dados numéricos , DNA Viral/sangue , Feminino , Gastroenterologia/normas , Vírus da Hepatite B/genética , Hepatite B Crônica/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Guias de Prática Clínica como Assunto , Atenção Primária à Saúde/normas , Estudos Retrospectivos , Fatores Sexuais
16.
Dig Dis Sci ; 59(1): 192-200, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24282055

RESUMO

BACKGROUND AND AIM: Hepatitis C virus (HCV) is an important cause of hepatocellular carcinoma (HCC) in Asians; however, it is often overlooked due to the high prevalence of hepatitis B virus in Asians. This study examines HCV-related HCC in Asians. METHODS: We conducted a retrospective cohort study of 792 consecutive Asian (n = 220) and non-Asian (n = 572) patients with HCV-related HCC identified at Stanford University Medical Center using International Classification of Diseases-9 diagnosis between July 1996 and June 2012. RESULTS: Asian patients were much older [66 (38-88) vs. 56 (31-87) years, P < 0.0001] and more likely to be female (33 vs. 19 %, P < 0.0001). A larger proportion of Asians were diagnosed with HCC within 2 years of HCV diagnosis (35 vs. 20 %, P = 0.001). Asian patients were more likely to undergo palliative therapy (46 vs. 28 %) and less likely to be listed for liver transplantation (20 vs. 48 %, P < 0.001), despite similar rates of meeting Milan criteria (52 vs. 58 %, P = 0.16). Overall, there was a trend for higher median survival rates in Asians (30 vs. 21 months, P = 0.091). Asians had higher long-term survival with palliative therapy only (5-year survival: 28 vs. 10 %, P < 0.0001); however, survival was similar among patients listed for liver transplantation. CONCLUSIONS: There were distinct differences in clinical presentations of Asian and non-Asian patients with HCV-related HCC. Asians with HCV-related HCC are less likely to undergo liver transplantation and more likely to have delayed HCV diagnosis. Improved strategies in HCV screening in Asians are needed, as it may lead to earlier diagnosis and treatment of HCV infection and possible prevention of HCC development.


Assuntos
Asiático , Carcinoma Hepatocelular/etnologia , Hepatite C/complicações , Neoplasias Hepáticas/etnologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Asiático/estatística & dados numéricos , California/epidemiologia , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/virologia , Feminino , Hepacivirus , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
17.
JCI Insight ; 9(3)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38175729

RESUMO

Intrahepatic macrophages in nonalcoholic steatohepatitis (NASH) are heterogenous and include proinflammatory recruited monocyte-derived macrophages. The receptor for advanced glycation endproducts (RAGE) is expressed on macrophages and can be activated by damage associated molecular patterns (DAMPs) upregulated in NASH, yet the role of macrophage-specific RAGE signaling in NASH is unclear. Therefore, we hypothesized that RAGE-expressing macrophages are proinflammatory and mediate liver inflammation in NASH. Compared with healthy controls, RAGE expression was increased in liver biopsies from patients with NASH. In a high-fat, -fructose, and -cholesterol-induced (FFC)-induced murine model of NASH, RAGE expression was increased, specifically on recruited macrophages. FFC mice that received a pharmacological inhibitor of RAGE (TTP488), and myeloid-specific RAGE KO mice (RAGE-MKO) had attenuated liver injury associated with a reduced accumulation of RAGE+ recruited macrophages. Transcriptomics analysis suggested that pathways of macrophage and T cell activation were upregulated by FFC diet, inhibited by TTP488 treatment, and reduced in RAGE-MKO mice. Correspondingly, the secretome of ligand-stimulated BM-derived macrophages from RAGE-MKO mice had an attenuated capacity to activate CD8+ T cells. Our data implicate RAGE as what we propose to be a novel and potentially targetable mediator of the proinflammatory signaling of recruited macrophages in NASH.


Assuntos
Hepatite , Hepatopatia Gordurosa não Alcoólica , Animais , Humanos , Camundongos , Macrófagos/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Receptor para Produtos Finais de Glicação Avançada/genética , Receptor para Produtos Finais de Glicação Avançada/metabolismo
18.
Neurosurgery ; 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38095422

RESUMO

The legacy of Stanford University's Department of Neurosurgery began in 1858, with the establishment of a new medical school on the West Coast. Stanford Neurosurgery instilled an atmosphere of dedication to neurosurgical care, scientific research, education, and innovation. We highlight key historical events leading to the formation of the medical school and neurosurgical department, the individuals who shaped the department's vision and expansion, as well as pioneering advances in research and clinical care. The residency program was started in 1961, establishing the basis of the current education model with a strong emphasis on training future leaders, and the Moyamoya Center, founded in 1991, became the largest Moyamoya referral center in the United States. The opening of Stanford Stroke Center (1992) and seminal clinical trials resulted in a significant impact on cerebrovascular disease by expanding the treatment window of IV thrombolysis and intra-arterial thrombectomy. The invention and implementation of CyberKnife® (1994) marks another important event that revolutionized the field of radiosurgery, and the development of Stanford's innovative Brain Computer Interface program is pushing the boundaries of this specialty. The more recent launch of the Neurosurgery Virtual Reality and Simulation Center (2017) exemplifies how Stanford is continuing to evolve in this ever-changing field. The department also became a model for diversity within the school as well as nationwide. The growth of Stanford Neurosurgery from one of the youngest neurosurgery departments in the country to a prominent comprehensive neurosurgery center mirrors the history of neurosurgery itself: young, innovative, and willing to overcome challenges.

19.
J Neurointerv Surg ; 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37793796

RESUMO

BACKGROUND: Balloon guide catheters (BGCs) have not been widely adopted, possibly due to the incompatibility of past-generation BGCs with large-bore intermediate catheters. The next-generation BGC is compatible with large-bore catheters. We compared outcomes of thrombectomy cases using BGCs versus conventional guide catheters. METHODS: We conducted a retrospective study of 110 thrombectomy cases using BGCs (n=55) and non-BGCs (n=55). Sixty consecutive thrombectomy cases in whom the BOBBY BGC was used at a single institution between February 2021 and March 2022 were identified. Of these, 55 BGC cases were 1:1 matched with non-BGC cases by proceduralists, age, gender, stent retriever + aspiration device versus aspiration-only, and site of occlusion. First-pass effect was defined as Thrombolysis In Cerebral Infarction 2b or higher with a single pass. RESULTS: The BGC and non-BGC cohorts had similar mean age (67.2 vs 68.9 years), gender distribution (43.6% vs 47.3% women), median initial National Institutes of Health Stroke Scale score (14 vs 15), and median pretreatment ischemic core volumes (12 mL vs 11.5 mL). BGC and non-BGC cases had similar rates of single pass (60.0% vs 54.6%), first-pass effect (58.2% vs 49.1%), and complications (1.8% vs 9.1%). In aspiration-only cases, the BGC cohort had a significantly higher rate of first-pass effect (100% vs 50.0%, p=0.01). BGC was associated with a higher likelihood of achieving a modified Rankin Scale score of 2 at discharge (OR 7.76, p=0.02). No additional procedural time was required for BGC cases (46.7 vs 48.2 min). CONCLUSION: BGCs may be safely adopted with comparable procedural efficacy, benefits to aspiration-only techniques, and earlier functional improvement compared with conventional guide catheters.

20.
Nat Commun ; 14(1): 2947, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-37268690

RESUMO

Derangements of the blood-brain barrier (BBB) or blood-retinal barrier (BRB) occur in disorders ranging from stroke, cancer, diabetic retinopathy, and Alzheimer's disease. The Norrin/FZD4/TSPAN12 pathway activates WNT/ß-catenin signaling, which is essential for BBB and BRB function. However, systemic pharmacologic FZD4 stimulation is hindered by obligate palmitoylation and insolubility of native WNTs and suboptimal properties of the FZD4-selective ligand Norrin. Here, we develop L6-F4-2, a non-lipidated, FZD4-specific surrogate which significantly improves subpicomolar affinity versus native Norrin. In Norrin knockout (NdpKO) mice, L6-F4-2 not only potently reverses neonatal retinal angiogenesis deficits, but also restores BRB and BBB function. In adult C57Bl/6J mice, post-stroke systemic delivery of L6-F4-2 strongly reduces BBB permeability, infarction, and edema, while improving neurologic score and capillary pericyte coverage. Our findings reveal systemic efficacy of a bioengineered FZD4-selective WNT surrogate during ischemic BBB dysfunction, with potential applicability to adult CNS disorders characterized by an aberrant blood-brain barrier.


Assuntos
Barreira Hematoencefálica , Receptores Frizzled , Camundongos , Animais , Barreira Hematoencefálica/metabolismo , Receptores Frizzled/genética , Receptores Frizzled/metabolismo , Retina/metabolismo , Barreira Hematorretiniana/metabolismo , Via de Sinalização Wnt
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