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1.
Acta Neuropathol Commun ; 12(1): 56, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589905

RESUMO

In malignant glioma, cytotoxic drugs are often inhibited from accessing the tumor site due to the blood-tumor barrier (BTB). Ibrutinib, FDA-approved lymphoma agent, inhibits Bruton tyrosine kinase (BTK) and has previously been shown to independently impair aortic endothelial adhesion and increase rodent glioma model survival in combination with cytotoxic therapy. Yet additional research is required to understand ibrutinib's effect on BTB function. In this study, we detail baseline BTK expression in glioma cells and its surrounding vasculature, then measure endothelial junctional expression/function changes with varied ibrutinib doses in vitro. Rat glioma cells and rodent glioma models were treated with ibrutinib alone (1-10 µM and 25 mg/kg) and in combination with doxil (10-100 µM and 3 mg/kg) to assess additive effects on viability, drug concentrations, tumor volume, endothelial junctional expression and survival. We found that ibrutinib, in a dose-dependent manner, decreased brain endothelial cell-cell adhesion over 24 h, without affecting endothelial cell viability (p < 0.005). Expression of tight junction gene and protein expression was decreased maximally 4 h after administration, along with inhibition of efflux transporter, ABCB1, activity. We demonstrated an additive effect of ibrutinib with doxil on rat glioma cells, as seen by a significant reduction in cell viability (p < 0.001) and increased CNS doxil concentration in the brain (56 ng/mL doxil alone vs. 74.6 ng/mL combination, p < 0.05). Finally, Ibrutinib, combined with doxil, prolonged median survival in rodent glioma models (27 vs. 16 days, p < 0.0001) with brain imaging showing a - 53% versus - 75% volume change with doxil alone versus combination therapy (p < 0.05). These findings indicate ibrutinib's ability to increase brain endothelial permeability via junctional disruption and efflux inhibition, to increase BTB drug entry and prolong rodent glioma model survival. Our results motivate the need to identify other BTB modifiers, all with the intent of improving survival and reducing systemic toxicities.


Assuntos
Adenina/análogos & derivados , Antineoplásicos , Doxorrubicina/análogos & derivados , Glioma , Piperidinas , Ratos , Animais , Roedores , Glioma/patologia , Antineoplásicos/uso terapêutico , Barreira Hematoencefálica/patologia , Polietilenoglicóis
2.
Int J Med Inform ; 181: 105300, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37995386

RESUMO

BACKGROUND: Antibiotic stewardship programs (ASP) aim to reduce inappropriate use of antibiotics, but their labor-intensive nature impedes their wide adoption. The present study introduces explainable machine learning (ML) models designed to prioritize inpatients who would benefit most from stewardship interventions. METHODS: A cohort of inpatients who received systemic antibiotics and were monitored by a multidisciplinary ASP team at a tertiary hospital in the Republic of Korea was assembled. Data encompassing over 130,000 patient-days and comprising more than 160 features from multiple domains, including prescription records, laboratory, microbiology results, and patient conditions was collected.Outcome labels were generated using medication administration history: discontinuation, switching from intravenous to oral medication (IV to PO), and early or late de-escalation. The models were trained using Extreme Gradient Boosting (XGB) and light Gradient Boosting Machine (LGBM), with SHapley Additive exPlanations (SHAP) analysis used to explain the model's predictions. RESULTS: The models demonstrated strong discrimination when evaluated on a hold-out test set(AUROC - IV to PO: 0.81, Early de-escalation: 0.78, Late de-escalation: 0.72, Discontinue: 0.80). The models identified 41%, 16%, 22%, and 17% more cases requiring discontinuation, IV to PO, early and late de-escalation, respectively, compared to the conventional length of therapy strategy, given that the same number of patients were reviewed by the ASP team. The SHAP results explain how each model makes their predictions, highlighting a unique set of important features that are well-aligned with the clinical intuitions of the ASP team. CONCLUSIONS: The models are expected to improve the efficiency of ASP activities by prioritizing cases that would benefit from different types of ASP interventions along with detailed explanations.


Assuntos
Gestão de Antimicrobianos , Humanos , Antibacterianos/uso terapêutico , Tempo de Internação , Centros de Atenção Terciária , República da Coreia
4.
Sci Rep ; 12(1): 11232, 2022 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-35789173

RESUMO

This study aimed to develop a model to predict the 5-year risk of developing end-stage renal disease (ESRD) in patients with type 2 diabetes mellitus (T2DM) using machine learning (ML). It also aimed to implement the developed algorithms into electronic medical records (EMR) system using Health Level Seven (HL7) Fast Healthcare Interoperability Resources (FHIR). The final dataset used for modeling included 19,159 patients. The medical data were engineered to generate various types of features that were input into the various ML classifiers. The classifier with the best performance was XGBoost, with an area under the receiver operator characteristics curve (AUROC) of 0.95 and area under the precision recall curve (AUPRC) of 0.79 using three-fold cross-validation, compared to other models such as logistic regression, random forest, and support vector machine (AUROC range, 0.929-0.943; AUPRC 0.765-0.792). Serum creatinine, serum albumin, the urine albumin-to-creatinine ratio, Charlson comorbidity index, estimated GFR, and medication days of insulin were features that were ranked high for the ESRD risk prediction. The algorithm was implemented in the EMR system using HL7 FHIR through an ML-dedicated server that preprocessed unstructured data and trained updated data.


Assuntos
Atenção à Saúde , Diabetes Mellitus Tipo 2 , Falência Renal Crônica , Humanos , Falência Renal Crônica/terapia , Modelos Logísticos , Aprendizado de Máquina
5.
J Spine Surg ; 5(2): 223-235, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31380476

RESUMO

BACKGROUND: The prevalence of spinal deformities increases with age, affecting between 30% and 68% of the elderly population (ages ≥65). The reported prevalence of complications associated with surgery for spinal deformities in this population ranges between 37% and 71%. Given the wide range of reported complication rates, the decision to perform surgery remains controversial. METHODS: A comprehensive search was conducted using PubMed, Embase, and Cochrane to identify studies reporting complications for spinal deformity surgery in the elderly population. Pooled prevalence estimates for individual complication types were calculated using the random-effects model. RESULTS: Of 5,586 articles, 14 met inclusion criteria. Fourteen complication types were reported, with at least 2 studies for each complication with the following pooled prevalence: reoperation (prevalence 19%; 95% CI, 9-36%; 107 patients); hardware failure (11%; 95% CI, 5-25%; 52 patients); infection (7%; 95% CI, 4-12%; 262 patients); pseudarthrosis (6%; 95% CI, 3-12%; 149 patients); radiculopathy (6%; 95% CI, 1-33%; 116 patients); cardiovascular event (5%; 95% CI, 1-32%; 121 patients); neurological deficit (5%; 95% CI, 2-15%; 248 patients); deep vein thrombosis (3%; 95% CI, 1-7%; 230 patients); pulmonary embolism (3%; 95% CI, 1-7%; 210 patients); pneumonia (3%; 95% CI, 1-11%; 210 patients); cerebrovascular or stroke event (2%; 95% CI, 0-9%; 85 patients); death (2%; 95% CI, 1-9%; 113 patients); myocardial infarction (2%; 95% CI, 1-6%; 210 patients); and postoperative hemorrhage (1%; 95% CI, 0-10%; 85 patients). CONCLUSIONS: Most complication types following spinal deformity surgery in the elderly had prevalence point estimates of <6%, while all were at least ≤19%. Additional studies are needed to further explore composite prevalence estimates and prevalence associated with traditional surgical approaches as compared to minimally-invasive procedures in the elderly.

6.
Nat Commun ; 10(1): 1547, 2019 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-30948712

RESUMO

The Hippo pathway maintains tissue homeostasis by negatively regulating the oncogenic transcriptional co-activators YAP and TAZ. Though functional inactivation of the Hippo pathway is common in tumors, mutations in core pathway components are rare. Thus, understanding how tumor cells inactivate Hippo signaling remains a key unresolved question. Here, we identify the kinase STK25 as an activator of Hippo signaling. We demonstrate that loss of STK25 promotes YAP/TAZ activation and enhanced cellular proliferation, even under normally growth-suppressive conditions both in vitro and in vivo. Notably, STK25 activates LATS by promoting LATS activation loop phosphorylation independent of a preceding phosphorylation event at the hydrophobic motif, which represents a form of Hippo activation distinct from other kinase activators of LATS. STK25 is significantly focally deleted across a wide spectrum of human cancers, suggesting STK25 loss may represent a common mechanism by which tumor cells functionally impair the Hippo tumor suppressor pathway.


Assuntos
Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Proteínas Serina-Treonina Quinases/fisiologia , Linhagem Celular , Proliferação de Células , Genes Supressores de Tumor , Via de Sinalização Hippo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais
7.
Mol Biol Cell ; 29(13): 1682-1692, 2018 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-29791254

RESUMO

Tetraploid cells, which are most commonly generated by errors in cell division, are genomically unstable and have been shown to promote tumorigenesis. Recent genomic studies have estimated that ∼40% of all solid tumors have undergone a genome-doubling event during their evolution, suggesting a significant role for tetraploidy in driving the development of human cancers. To safeguard against the deleterious effects of tetraploidy, nontransformed cells that fail mitosis and become tetraploid activate both the Hippo and p53 tumor suppressor pathways to restrain further proliferation. Tetraploid cells must therefore overcome these antiproliferative barriers to ultimately drive tumor development. However, the genetic routes through which spontaneously arising tetraploid cells adapt to regain proliferative capacity remain poorly characterized. Here, we conducted a comprehensive gain-of-function genome-wide screen to identify microRNAs (miRNAs) that are sufficient to promote the proliferation of tetraploid cells. Our screen identified 23 miRNAs whose overexpression significantly promotes tetraploid proliferation. The vast majority of these miRNAs facilitate tetraploid growth by enhancing mitogenic signaling pathways (e.g., miR-191-3p); however, we also identified several miRNAs that impair the p53/p21 pathway (e.g., miR-523-3p), and a single miRNA (miR-24-3p) that potently inactivates the Hippo pathway via down-regulation of the tumor suppressor gene NF2. Collectively, our data reveal several avenues through which tetraploid cells may regain the proliferative capacity necessary to drive tumorigenesis.


Assuntos
Testes Genéticos , MicroRNAs/genética , Tetraploidia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proliferação de Células/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Regulação para Baixo/genética , Humanos , MicroRNAs/metabolismo , Mitógenos/metabolismo , Neurofibromina 2/metabolismo , Fosfoproteínas/metabolismo , Transdução de Sinais , Fatores de Transcrição , Proteína Supressora de Tumor p53/metabolismo , Proteínas de Sinalização YAP
8.
J Med Internet Res ; 19(10): e340, 2017 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-29046269

RESUMO

BACKGROUND: There has been a lack of understanding on what types of specific clinical information are most valuable for doctors to access through mobile-based electronic medical records (m-EMRs) and when they access such information. Furthermore, it has not been clearly discussed why the value of such information is high. OBJECTIVE: The goal of this study was to investigate the types of clinical information that are most valuable to doctors to access through an m-EMR and when such information is accessed. METHODS: Since 2010, an m-EMR has been used in a tertiary hospital in Seoul, South Korea. The usage logs of the m-EMR by doctors were gathered from March to December 2015. Descriptive analyses were conducted to explore the overall usage patterns of the m-EMR. To assess the value of the clinical information provided, the usage patterns of both the m-EMR and a hospital information system (HIS) were compared on an hourly basis. The peak usage times of the m-EMR were defined as continuous intervals having normalized usage values that are greater than 0.5. The usage logs were processed as an indicator representing specific clinical information using factor analysis. Random intercept logistic regression was used to explore the type of clinical information that is frequently accessed during the peak usage times. RESULTS: A total of 524,929 usage logs from 653 doctors (229 professors, 161 fellows, and 263 residents; mean age: 37.55 years; males: 415 [63.6%]) were analyzed. The highest average number of m-EMR usage logs (897) was by medical residents, whereas the lowest (292) was by surgical residents. The usage amount for three menus, namely inpatient list (47,096), lab results (38,508), and investigation list (25,336), accounted for 60.1% of the peak time usage. The HIS was used most frequently during regular hours (9:00 AM to 5:00 PM). The peak usage time of the m-EMR was early in the morning (6:00 AM to 10:00 AM), and the use of the m-EMR from early evening (5:00 PM) to midnight was higher than during regular business hours. Four factors representing the types of clinical information were extracted through factor analysis. Factors related to patient investigation status and patient conditions were associated with the peak usage times of the m-EMR (P<.01). CONCLUSIONS: Access to information regarding patient investigation status and patient conditions is crucial for decision making during morning activities, including ward rounds. The m-EMRs allow doctors to maintain the continuity of their clinical information regardless of the time and location constraints. Thus, m-EMRs will best evolve in a manner that enhances the accessibility of clinical information helpful to the decision-making process under such constraints.


Assuntos
Registros Eletrônicos de Saúde/estatística & dados numéricos , Aplicativos Móveis/estatística & dados numéricos , Adulto , Humanos , Masculino , Médicos
9.
PLoS Biol ; 15(7): e2001246, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28683067

RESUMO

Clinical and preclinical studies indicate that early postnatal exposure to anesthetics can lead to lasting deficits in learning and other cognitive processes. The mechanism underlying this phenomenon has not been clarified and there is no treatment currently available. Recent evidence suggests that anesthetics might cause persistent deficits in cognitive function by disrupting key events in brain development. The hippocampus, a brain region that is critical for learning and memory, contains a large number of neurons that develop in the early postnatal period, which are thus vulnerable to perturbation by anesthetic exposure. Using an in vivo mouse model we demonstrate abnormal development of dendrite arbors and dendritic spines in newly generated dentate gyrus granule cell neurons of the hippocampus after a clinically relevant isoflurane anesthesia exposure conducted at an early postnatal age. Furthermore, we find that isoflurane causes a sustained increase in activity in the mechanistic target of rapamycin pathway, and that inhibition of this pathway with rapamycin not only reverses the observed changes in neuronal development, but also substantially improves performance on behavioral tasks of spatial learning and memory that are impaired by isoflurane exposure. We conclude that isoflurane disrupts the development of hippocampal neurons generated in the early postnatal period by activating a well-defined neurodevelopmental disease pathway and that this phenotype can be reversed by pharmacologic inhibition.


Assuntos
Anestésicos Inalatórios/toxicidade , Disfunção Cognitiva/induzido quimicamente , Hipocampo/efeitos dos fármacos , Isoflurano/toxicidade , Serina-Treonina Quinases TOR/metabolismo , Animais , Espinhas Dendríticas/efeitos dos fármacos , Espinhas Dendríticas/patologia , Exposição Ambiental , Hipocampo/crescimento & desenvolvimento , Hipocampo/patologia , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/patologia
10.
Stud Health Technol Inform ; 245: 1231, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29295318

RESUMO

In recent years, major hospitals have started using mobile electronic medical records (m-EMR). However, usage patterns based on actual log data have rarely been discussed. In this study, we investigated usage patterns of a m-EMR in several dimensions to understand the m-EMR in depth.


Assuntos
Registros Eletrônicos de Saúde , Médicos , Hospitais , Humanos , Telemedicina
11.
Mol Biol Cell ; 27(21): 3210-3213, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27799497

RESUMO

The nuclear envelope, composed of two lipid bilayers and numerous accessory proteins, has evolved to house the genetic material of all eukaryotic cells. In so doing, the nuclear envelope provides a physical barrier between chromosomes and the cytoplasm. Once believed to be highly stable, recent studies demonstrate that the nuclear envelope is prone to rupture. These rupture events expose chromosomal DNA to the cytoplasmic environment and have the capacity to promote DNA damage. Thus nuclear rupture may be an unappreciated mechanism of mutagenesis.


Assuntos
Membrana Nuclear/metabolismo , Membrana Nuclear/fisiologia , Núcleo Celular/metabolismo , Núcleo Celular/fisiologia , Cromossomos/metabolismo , Citoplasma/metabolismo , Dano ao DNA/fisiologia , Células Eucarióticas/metabolismo , Instabilidade Genômica/genética , Neoplasias/genética , Proteínas Nucleares/metabolismo
12.
J Neurosurg Anesthesiol ; 28(4): 405-412, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27768676

RESUMO

BACKGROUND: Early postnatal exposure to general anesthetic agents causes a lasting impairment in learning and memory in animal models. One hypothesis to explain this finding is that exposure to anesthetic agents during critical points in neural development disrupts the formation of brain circuitry. Here, we explore the effects of sevoflurane on the neuronal growth cone, a specialization at the growing end of axons and dendrites that is responsible for the targeted growth that underlies connectivity between neurons. METHODS: Dissociated neuronal cultures were prepared from embryonic mouse neocortex. Time-lapse images of live growth cones exposed to anesthetics were taken using differential interference contrast microscopy, and the rate of change of the area of the lamellipodia and the speed of the filopodial tip were quantified as measures of motility. The involvement of the p75 neurotropin receptor (p75NTR) was tested using inhibitors applied to the media and by a coimmunoprecipitation assay. RESULTS: The rate of lamellipodial area change and filopodial tip velocity in both axonal and dendritic growth cones was significantly reduced with sevoflurane exposure between 2% and 6%. Motility could be substantially restored by treatment with Y27632 and TAT-peptide 5, which are inhibitors of Rho Kinase and p75NTR, respectively. Sevoflurane results in reduced coimmunoprecipitation of Rho-Guanosine-5'-diphosphate dissociation inhibitor after pulldown with p75NTR. CONCLUSIONS: Sevoflurane interferes with growth cone motility, which is a critical process in brain circuitry formation. Our data suggest that this may occur through an action on the p75NTR, which promotes growth inhibitory signaling by the Rho pathway.


Assuntos
Anestésicos Inalatórios/efeitos adversos , Cones de Crescimento/efeitos dos fármacos , Éteres Metílicos/efeitos adversos , Animais , Células Cultivadas , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , Sevoflurano , Transdução de Sinais/efeitos dos fármacos
13.
J Med Internet Res ; 18(8): e216, 2016 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-27492880

RESUMO

BACKGROUND: Mobile mental-health trackers are mobile phone apps that gather self-reported mental-health ratings from users. They have received great attention from clinicians as tools to screen for depression in individual patients. While several apps that ask simple questions using face emoticons have been developed, there has been no study examining the validity of their screening performance. OBJECTIVE: In this study, we (1) evaluate the potential of a mobile mental-health tracker that uses three daily mental-health ratings (sleep satisfaction, mood, and anxiety) as indicators for depression, (2) discuss three approaches to data processing (ratio, average, and frequency) for generating indicator variables, and (3) examine the impact of adherence on reporting using a mobile mental-health tracker and accuracy in depression screening. METHODS: We analyzed 5792 sets of daily mental-health ratings collected from 78 breast cancer patients over a 48-week period. Using the Patient Health Questionnaire-9 (PHQ-9) as the measure of true depression status, we conducted a random-effect logistic panel regression and receiver operating characteristic (ROC) analysis to evaluate the screening performance of the mobile mental-health tracker. In addition, we classified patients into two subgroups based on their adherence level (higher adherence and lower adherence) using a k-means clustering algorithm and compared the screening accuracy between the two groups. RESULTS: With the ratio approach, the area under the ROC curve (AUC) is 0.8012, indicating that the performance of depression screening using daily mental-health ratings gathered via mobile mental-health trackers is comparable to the results of PHQ-9 tests. Also, the AUC is significantly higher (P=.002) for the higher adherence group (AUC=0.8524) than for the lower adherence group (AUC=0.7234). This result shows that adherence to self-reporting is associated with a higher accuracy of depression screening. CONCLUSIONS: Our results support the potential of a mobile mental-health tracker as a tool for screening for depression in practice. Also, this study provides clinicians with a guideline for generating indicator variables from daily mental-health ratings. Furthermore, our results provide empirical evidence for the critical role of adherence to self-reporting, which represents crucial information for both doctors and patients.


Assuntos
Neoplasias da Mama/psicologia , Depressão/diagnóstico , Programas de Rastreamento/métodos , Aplicativos Móveis , Smartphone , Telemedicina/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Curva ROC
15.
Dev Neurosci ; 37(4-5): 428-39, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26087836

RESUMO

Neonatal hypoxic-ischemic injury (HI) results in widespread cerebral encephalopathy and affects structures that are essential for neurocognitive function, such as the hippocampus. The dentate gyrus contains a reservoir of neural stem and progenitor cells (NSPCs) that are critical for postnatal development and normal adult function of the hippocampus, and may also facilitate the recovery of function after injury. Using a neonatal mouse model of mild-to-moderate HI and immunohistochemical analysis of NSPC development markers, we asked whether these cells are vulnerable to HI and how they respond to both injury and hypothermic therapy. We found that cleaved caspase-3 labeling in the subgranular zone, where NSPCs are located, is increased by more than 30-fold after HI. The population of cells positive for both proliferating cell nuclear antigen and nestin (PCNA+Nes+), which represent primarily actively proliferating NSPCs, are acutely decreased by 68% after HI. The NSPC population expressing NeuroD1, a marker for NSPCs transitioning to become fate-committed neural progenitors, was decreased by 47%. One week after HI, there was a decrease in neuroblasts and immature neurons in the dentate gyrus, as measured by doublecortin (DCX) immunolabeling, and at the same time PCNA+Nes+ cell density was increased by 71%. NSPCs expressing Tbr2, which identifies a highly proliferative intermediate neural progenitor population, increased by 107%. Hypothermia treatment after HI partially rescues both the acute decrease in PCNA+Nes+ cell density at 1 day after injury and the chronic loss of DCX immunoreactivity and reduction in NeuroD1 cell density measured at 1 week after injury. Thus, we conclude that HI causes an acute loss of dentate gyrus NSPCs, and that hypothermia partially protects NSPCs from HI.


Assuntos
Giro Denteado/patologia , Hipotermia Induzida , Hipóxia-Isquemia Encefálica/patologia , Hipóxia-Isquemia Encefálica/terapia , Células-Tronco Neurais/fisiologia , Neurogênese/fisiologia , Animais , Animais Recém-Nascidos , Giro Denteado/citologia , Modelos Animais de Doenças , Proteína Duplacortina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/citologia
16.
Oncotarget ; 5(22): 10959-60, 2014 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-25526024
17.
BMC Cancer ; 13: 291, 2013 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23768125

RESUMO

BACKGROUND: The inhibitor of differentiation (ID) genes have been implicated as promoters of tumor progression and metastasis in many human cancers. The current study investigated the expression and functional roles of ID genes in seeding and prognosis of medulloblastoma. METHODS: ID gene expression was screened in human medulloblastoma tissues. Knockdown of ID3 gene was performed in medulloblastoma cells in vitro. The expression of metastasis-related genes after ID3 knockdown was assessed. The effect of ID3 knockdown on tumor seeding was observed in an animal model in vivo. The survival of medulloblastoma patients was plotted according to the ID3 expression levels. RESULTS: Significantly higher ID3 expression was observed in medulloblastoma with cerebrospinal fluid seeding than tumors without seeding. Knockdown of ID3 decreased proliferation, increased apoptosis, and suppressed the migration of D283 medulloblastoma cells in vitro. In a seeding model of medulloblastoma, ID3 knockdown in vivo with shRNA inhibited the growth of primary tumors, prevented the development of leptomeningeal seeding, and prolonged animal survival. High ID3 expression was associated with shorter survival of medulloblastoma patients, especially in Group 4 medulloblastomas. CONCLUSIONS: High ID3 expression is associated with medulloblastoma seeding and is a poor prognostic factor, especially in patients with Group 4 tumors. ID3 may represent the metastatic/ aggressive phenotype of a subgroup of medulloblastoma.


Assuntos
Neoplasias Cerebelares/patologia , Proteínas Inibidoras de Diferenciação/metabolismo , Meduloblastoma/patologia , Proteínas de Neoplasias/metabolismo , Animais , Apoptose/fisiologia , Western Blotting , Neoplasias Cerebelares/líquido cefalorraquidiano , Intervalo Livre de Doença , Feminino , Técnicas de Silenciamento de Genes , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Estimativa de Kaplan-Meier , Meduloblastoma/líquido cefalorraquidiano , Camundongos , Camundongos Endogâmicos BALB C , Invasividade Neoplásica/patologia , Prognóstico , Modelos de Riscos Proporcionais , RNA Interferente Pequeno , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise Serial de Tecidos , Transplante Heterólogo
18.
Ann Dermatol ; 21(1): 18-26, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20548850

RESUMO

BACKGROUND: Malassezia yeasts are normal flora of the skin that are discovered in 75~98% of health subjects, but since its association with various skin disorders have been known, many studies have been conducted in the distribution of the yeasts. OBJECTIVE: To isolate, identify, and classify Malassezia yeasts from the normal human skin of Koreans by using the rapid and accurate molecular biology method (26S rDNA PCR-RFLP) which overcome the limits of morphological and biochemical methods, and to gather a basic database that will show its relation to various skin diseases. METHODS: Malassezia yeasts were cultured from clinically healthy human skin using scrub-wash technique at five sites (forehead, cheek, chest, upper arm, and thigh) and swabbing technique at scalp in 160 participants comprised of 80 males and 80 females aged from 0 to 80. Identification of obtained strains were placed into the one of the 11 species by 26S rDNA PCR-RFLP. RESULTS: An overall positive culture rate was 62.4% (599/960). As shown in the experiment groups by their age, the positive culture rate was the highest (74.2%) in the age 21~30 and 31~40 (89/120). In the experiment groups by different body areas, the scalp showed the highest positive culture rate of 90% (144/160). On analysis of 26S rDNA PCR-RFLP, M. globosa was the most predominant species in the age 0~10 (32.8%), 11~20 (28.9%), 21~30 (32.3%). M. restricta was identified as predominant species in the age 41~50 (27.9%), 61~70 (31.5%) and 71~80 (24.0%). In the age 31~40 years, M. sympodialis was found to be the most common species (24.6%). According to body site, M. restricta was more frequently recovered in the scalp (56.8%), forehead (39.8%) and cheek (24.0%) and while M. globosa was more frequently recovered in the chest (36.8%). Higher positive culture rates of Malassezia yeasts were shown in male subjects than female counterparts in all body areas except scalp (p<0.05). Especially in this study, M. dermatis, newly isolated Malassezia species from atopic dermatitis patient in Japan, was isolated and identified in 19 cases (1.9%) in healthy subjects. CONCLUSION: The key is to recognize the existence of a difference in the type of Malassezia species in different ages as well as body areas, which reflects differing skin lipid levels in various ages and different body areas. Moreover, 26S rDNA PCR-RFLP analysis which was opted in this study could provide a sensitive and rapid identification system for Malassezia species, which may be applied to epidemiological surveys and clinical practice.

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