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1.
Cereb Cortex ; 29(2): 657-665, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29329367

RESUMO

In the past decade, several studies have investigated the effects of transcranial direct current stimulation (tDCS) on episodic memory abilities. However, the specific conditions under which tDCS affects memory remain largely unclear. Here, we report data from 4 experiments aimed at investigating the effects of anodal tDCS over the left ventrolateral prefrontal cortex (VLPFC) on verbal episodic memory. We evaluated tDCS-induced effects as a function of time of administration, nature of the memory encoding task, and age of the participants. A robust enhancement of memory performance was only found when anodal tDCS was delivered during intentional memorization. This enhancement was evident in young and older adults. tDCS applied during incidental memorization or during retrieval did not induce any modulation of memory performance, and memory was unaffected by offline administration before encoding or retrieval. These results show that the modulation of episodic memory functions by anodal tDCS over the left VLPFC is dependent upon the time of administration and the nature of the memory task. The findings may help profile the optimal stimulation protocols for neurorehabilitation interventions on individuals with memory decline.


Assuntos
Memória Episódica , Rememoração Mental/fisiologia , Córtex Pré-Frontal/fisiologia , Estimulação Transcraniana por Corrente Contínua/métodos , Adulto , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos , Distribuição Aleatória , Adulto Jovem
2.
Pediatr Emerg Care ; 36(12): e745-e746, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32384395

RESUMO

Neuroleptic malignant syndrome is a challenging diagnosis because it mimics many other conditions. We present a case of a 16-year-old boy with spastic cerebral palsy who presented with severe agitation, hyperthermia, and autonomic dysfunction. He arrived to a community pediatric hospital without a caregiver to provide a detailed history, which further complicated his management.


Assuntos
Paralisia Cerebral , Síndrome Maligna Neuroléptica , Agitação Psicomotora , Adolescente , Humanos , Masculino
3.
Int J Cancer ; 145(11): 3022-3032, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31018249

RESUMO

The normal colon epithelium is transformed into its neoplastic counterpart through a series of genetic alterations in driver genes including activating mutations in PIK3CA. Treatment often involves surgery followed by 5-fluorouracil (5-FU) based therapy, which has limited efficiency and serious side effects. We sought to determine whether fisetin, a dietary flavonoid, alone or in combination with 5-FU affected tumorigenesis in the mammalian intestine. We first determined the effect of fisetin, 5-FU or their combination on PIK3CA-mutant and PIK3CA wild-type colon cancer cells by assessing cell viability, colony formation, apoptosis and effects on PI3K/AKT/mTOR signaling. Treatment of PIK3CA-mutant cells with fisetin and 5-FU reduced the expression of PI3K, phosphorylation of AKT, mTOR, its target proteins, constituents of mTOR signaling complex and this treatment increased the phosphorylation of AMPKα. We then determined whether fisetin and 5-FU together or singly affected tumorigenesis in ApcMin/+ mice that also express constitutively active PI3K in the distal small intestine and colon. Tumor incidence was markedly lower in fisetin-treated FC1 3K1 ApcMin/+ mice that also express constitutively active PI3K in distal small intestine and colon, as compared to control animals, indicating that fisetin is a strong preventive agent. In addition, the combination of fisetin and 5-FU also reduced the total number of intestinal tumors. Fisetin could be used as a preventive agent plus an adjuvant with 5-FU for the treatment of PIK3CA-mutant colorectal cancer.


Assuntos
Classe I de Fosfatidilinositol 3-Quinases/genética , Neoplasias Colorretais/tratamento farmacológico , Flavonoides/administração & dosagem , Fluoruracila/administração & dosagem , Mutação , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais/genética , Sinergismo Farmacológico , Flavonoides/farmacologia , Flavonóis , Fluoruracila/farmacologia , Células HCT116 , Células HT29 , Humanos , Camundongos , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Semin Cancer Biol ; 40-41: 130-140, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27163728

RESUMO

The last few decades have seen a resurgence of interest among the scientific community in exploring the efficacy of natural compounds against various human cancers. Compounds of plant origin belonging to different groups such as alkaloids, flavonoids and polyphenols evaluated for their cancer preventive effects have yielded promising data, thereby offering a potential therapeutic alternative against this deadly disease. The flavonol fisetin (3,3',4',7-tetrahydroxyflavone), present in fruits and vegetables such as strawberries, apple, cucumber, persimmon, grape and onion, was shown to possess anti-microbial, anti-inflammatory, anti-oxidant and more significantly anti-carcinogenic activity when assessed in diverse cell culture and animal model systems. The purpose of this review is to update and discuss key findings obtained till date from in vitro and in vivo studies on fisetin, with special focus on its anti-cancer role. The molecular mechanism(s) described in the observed growth inhibitory effects of fisetin in different cancer cell types is also summarized. Moreover, an attempt is made to delineate the direction of future studies that could lead to the development of fisetin as a potent chemopreventive/chemotherapeutic agent against cancer.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Flavonoides/farmacologia , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos Fitogênicos/uso terapêutico , Ensaios de Seleção de Medicamentos Antitumorais , Flavonoides/uso terapêutico , Flavonóis , Humanos , Terapia de Alvo Molecular , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico
5.
Carcinogenesis ; 38(2): 184-195, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-27881463

RESUMO

Many purified compounds from dietary sources have been investigated for their anticancer activities. The main issue with most agents is their effectiveness at high doses which generally could not be delivered to humans through dietary consumption. Here, we observed that cucurbitacin B, a tetracyclic triterpenoid present in pumpkins, gourds and squashes, exhibits antiproliferative effects on human non-small cell lung cancer (NSCLC) cells at nanomolar concentrations. Treatment with cucurbitacin B (0.2-0.6 µM; 24 h) was found to result in decrease in the viability of EGFR-wild type (A549 and H1792) and EGFR-mutant lung cancer cells (H1650 and H1975) and reduction in cell-colonies but had only minimal effect on normal human bronchial epithelial cells. Treatment with cucurbitacin B also caused inhibition of PI3K/mTOR and signal transducer and activator of transcription (STAT)-3 signaling along with simultaneous activation of AMPKα levels in both EGFR-wild type and EGFR-mutant lung cancer cells. Cucurbitacin B caused specific increase in the protein and mRNA expression of sestrin-3 in EGFR-mutant lung cancer cells, but not in EGFR-wild type cells. Treatment with cucurbitacin B to sestrin-3 siRNA treated EGFR-mutant cells further amplified the decrease in cell-viability and caused more sustained G2-phase cell cycle arrest, suggesting that these effects are mediated partly through sestrin-3. We also found that sestrin-3 has a role in the induction of apoptosis by cucurbitacin B in both EGFR-wild type and EGFR-mutant lung cancer cells. These findings suggest novel mechanism by the modulation of sestrin-3 for the action of cucurbitacin B and suggest that it could be developed as an agent for therapy of NSCLC.


Assuntos
Receptores ErbB/genética , Proteínas de Choque Térmico/biossíntese , Neoplasias Pulmonares/tratamento farmacológico , Triterpenos/administração & dosagem , Células A549 , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico/genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Mutação , Fosfatidilinositol 3-Quinases/genética , Transdução de Sinais/efeitos dos fármacos
6.
Pediatr Emerg Care ; 33(1): 10-13, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27618589

RESUMO

BACKGROUND: Effective communication between physician and patient is essential to optimize care after discharge from the emergency department (ED). Written discharge care instructions (DCI) complement verbal instructions and have been shown to improve communication and patient management. In 2012, Centers for Medicare and Medicaid Services proposed a quality measure (OP-19) that assesses compliance with key elements considered essential for high-quality written DCI. OBJECTIVE: To evaluate the impact of a QI intervention on improving quality of written DCI in a pediatric emergency department (PED). METHODS: A QI initiative was conducted at a tertiary PED with greater than 60,000 annual visits. Based on Centers for Medicare and Medicaid Services OP-19 measure and group consensus, 8 elements were defined a priori as requisites for good quality DCI. These elements are:Providers reviewed a random sample of DCI of patients. Proportion of DCI that had each element documented was compared between preintervention phase (PRE) and postintervention phase (POST). RESULTS: Three hundred twenty-nine DCI (PRE) and 1434 DCI (POST) were reviewed. The POST DCI showed statistically significant improvement for each of the 8 elements. The bundle measure (proportion containing all 8 elements) increased from 23% (PRE) to 79% (POST) (P < 0.001). CONCLUSIONS: The ED DCI improved in all 8 elements after a QI intervention. A detailed DCI at ED discharge enhances the patient's ability to comply with postdischarge treatment plan. Further studies are needed to evaluate the impact of improving DCI on ED return rates and other outcomes.


Assuntos
Serviço Hospitalar de Emergência/normas , Alta do Paciente/normas , Melhoria de Qualidade , Criança , Documentação/normas , Feminino , Pesquisa sobre Serviços de Saúde , Humanos , Masculino , Estados Unidos
7.
Skin Pharmacol Physiol ; 28(4): 177-88, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25620035

RESUMO

BACKGROUND: Psoriasis is a chronic inflammatory disorder of skin and joints for which conventional treatments that are effective in clearing the moderate-to-severe disease are limited due to long-term safety issues. This necessitates exploring the usefulness of botanical agents for treating psoriasis. We previously showed that delphinidin, a diet-derived anthocyanidin endowed with antioxidant and anti-inflammatory properties, induces normal epidermal keratinocyte differentiation and suggested its possible usefulness for the treatment of psoriasis [1]. OBJECTIVES: To investigate the effect of delphinidin (0-20 µM; 2-5 days) on psoriatic epidermal keratinocyte differentiation, proliferation and inflammation using a three-dimensional reconstructed human psoriatic skin equivalent (PSE) model. METHODS: PSEs and normal skin equivalents (NSEs) established on fibroblast-contracted collagen gels with respective psoriatic and normal keratinocytes and treated with/without delphinidin were analyzed for histology, expression of markers of differentiation, proliferation and inflammation using histomorphometry, immunoblotting, immunochemistry, qPCR and cultured supernatants for cytokine with a Multi-Analyte ELISArray Kit. RESULTS: Our data show that treatment of PSE with delphinidin induced (1) cornification without affecting apoptosis and (2) the mRNA and protein expression of markers of differentiation (caspase-14, filaggrin, loricrin, involucrin). It also decreased the expression of markers of proliferation (Ki67 and proliferating cell nuclear antigen) and inflammation (inducible nitric oxide synthase and antimicrobial peptides S100A7-psoriasin and S100A15-koebnerisin, which are often induced in psoriatic skin). ELISArray showed increased release of psoriasis-associated keratinocyte-derived proinflammatory cytokines in supernatants of the PSE cultures, and this increase was significantly suppressed by delphinidin. CONCLUSIONS: These observations provide a rationale for developing delphinidin for the management of psoriasis.


Assuntos
Antocianinas/farmacologia , Anti-Inflamatórios/farmacologia , Queratinócitos/efeitos dos fármacos , Modelos Biológicos , Psoríase/tratamento farmacológico , Pele/efeitos dos fármacos , Caspases/genética , Caspases/metabolismo , Diferenciação Celular , Células Cultivadas , Citocinas/metabolismo , Proteínas Filagrinas , Humanos , Queratinócitos/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Psoríase/metabolismo , RNA Mensageiro/metabolismo , Proteína A7 Ligante de Cálcio S100 , Proteínas S100/genética , Pele/metabolismo
8.
Carcinogenesis ; 35(2): 415-23, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24072771

RESUMO

In preclinical animal models, several phytochemicals have shown excellent potential to be used as effective agents in preventing and treating many cancers. However, the limited bioavailability of active agents could be one reason for their restricted usefulness for human consumption. To overcome this limitation, we recently introduced the concept of nanochemoprevention by encapsulating useful bioactive food components for their slow and sustained release. Here, we report the synthesis, characterization and efficacy assessment of a nanotechnology-based oral formulation of chitosan nanoparticles encapsulating epigallocatechin-3-gallate (Chit-nanoEGCG) for the treatment of prostate cancer (PCa) in a preclinical setting. Chit-nanoEGCG with a size of <200nm diameter and encapsulating EGCG as determined by dynamic light scattering and transmission electron microscope showed slow release of EGCG in simulated gastric juice acidic pH and faster release in simulated intestinal fluid. The antitumor efficacy of Chit-nanoEGCG was assessed in subcutaneously implanted 22Rν1 tumor xenografts in athymic nude mice. Treatment with Chit-nanoEGCG resulted in significant inhibition of tumor growth and secreted prostate-specific antigen levels compared with EGCG and control groups. In tumor tissues of mice treated with Chit-nanoEGCG, compared with groups treated with EGCG and controls, there was significant (i) induction of poly (ADP-ribose) polymerases cleavage, (ii) increase in the protein expression of Bax with concomitant decrease in Bcl-2, (iii) activation of caspases and (iv) reduction in Ki-67 and proliferating cell nuclear antigen. Through this study, we propose a novel preventive and therapeutic modality for PCa using EGCG that addresses issues related to bioavailability.


Assuntos
Catequina/análogos & derivados , Proliferação de Células/efeitos dos fármacos , Quitosana/química , Nanopartículas/administração & dosagem , Nanotecnologia , Neoplasias da Próstata/prevenção & controle , Chá/química , Administração Oral , Animais , Anticarcinógenos/administração & dosagem , Anticarcinógenos/farmacologia , Caspases/metabolismo , Catequina/administração & dosagem , Catequina/farmacologia , Ensaio de Imunoadsorção Enzimática , Humanos , Immunoblotting , Técnicas Imunoenzimáticas , Masculino , Camundongos , Camundongos Nus , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/patologia , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína X Associada a bcl-2/metabolismo
9.
Nanomedicine ; 10(8): 1619-26, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24965756

RESUMO

Earlier we demonstrated the anti-proliferative and pro-apoptotic effects of green tea polyphenol epigallocatechin-3-gallate (EGCG) on human melanoma cells (Int J Cancer. 2005; 114(4): 513-21). The doses used in this study were not physiologically attainable and for chemoprevention the preferred route of administration is oral consumption. To overcome these shortcomings, and taking advantage of our novel concept of nanochemoprevention (Cancer Res. 2009;69(5):1712-6), we developed a nanotechnology based oral delivery system to encapsulate EGCG. Here, using human melanoma Mel 928 cells we demonstrate 8-fold dose advantage of this nanoformulation over native EGCG. Further, nano-EGCG treated cells showed marked induction of apoptosis and cell cycle inhibition along with the growth of Mel 928 tumor xenograft. Nano-EGCG also inhibited proliferation (Ki-67 and PCNA) and induced apoptosis (Bax, PARP) in tumors harvested from the treated mice. These observations warrant further in vivo efficacy studies of nano-EGCG in robust animal models of human melanoma. FROM THE CLINICAL EDITOR: This team of investigators developed a nanotechnology based oral delivery system to encapsulate EGCG, a green tea-derived polyphenol in chitosan nanoparticles. Using human melanoma cells, an eight-fold dose advantage was demonstrated over native EGCG, leading to measurable apoptosis induction and proliferation inhibition, warranting further in vivo investigations.


Assuntos
Catequina/análogos & derivados , Quitosana/química , Melanoma/tratamento farmacológico , Nanopartículas/química , Animais , Apoptose/efeitos dos fármacos , Catequina/química , Catequina/farmacologia , Catequina/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Masculino , Camundongos , Camundongos Nus , Nanotecnologia/métodos , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Exp Dermatol ; 22(5): 342-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23614741

RESUMO

Delphinidin (Del), [3,5,7,3'-,4'-,5'-hexahydroxyflavylium], an anthocyanidin and a potent antioxidant abundantly found in pigmented fruits and vegetables exhibits proapoptotic effects in many cancer cells. Here, we determined the effect of Del on growth, apoptosis and differentiation of normal human epidermal keratinocytes (NHEKs) in vitro in submerged cultures and examined its effects in a three-dimensional (3D) epidermal equivalent (EE) model that permits complete differentiation reminiscent of in vivo skin. Treatment of NHEKs with Del (10-40 µm; 24-48 h) significantly enhanced keratinocyte differentiation. In Del-treated cells, there was marked increase in human involucrin (hINV) promoter activity with simultaneous increase in the mRNA and protein expressions of involucrin and other epidermal differentiation markers including procaspase-14 and transglutaminase-1 (TGM1), but without any effect on TGM2. Del treatment of NHEKs was associated with minimal decrease in cell viability, which was not associated with apoptosis as evident by lack of modulation of caspases, apoptosis-related proteins including Bcl-2 family of proteins and poly(ADP-ribose) polymerase cleavage. To establish the in vivo relevance of our observations in submerged cultures, we then validated these effects in a 3D EE model, where Del was found to significantly enhance cornification and increase the protein expression of cornification markers including caspase-14 and keratin 1. For the first time, we show that Del induces epidermal differentiation using an experimental system that closely mimics in vivo human skin. These observations suggest that Del could be a useful agent for dermatoses associated with epidermal barrier defects including aberrant keratinization, hyperproliferation or inflammation observed in skin diseases like psoriasis and ichthyoses.


Assuntos
Antocianinas/farmacologia , Antioxidantes/farmacologia , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Caspases/metabolismo , Técnicas de Cultura de Células/métodos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Células Epidérmicas , Prepúcio do Pênis/citologia , Frutas/química , Expressão Gênica/efeitos dos fármacos , Humanos , Recém-Nascido , Masculino , Técnicas de Cultura de Órgãos/métodos , Regiões Promotoras Genéticas/fisiologia , Precursores de Proteínas/genética , Verduras/química
11.
Am J Emerg Med ; 31(1): 166-72, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23000332

RESUMO

BACKGROUND: The use of ondansetron in children with vomiting after a head injury has not been well studied. Concern about masking serious injury is a potential barrier to its use. OBJECTIVE: The aim of this study was to evaluate the use of ondansetron in children with head injury and symptoms of vomiting in the pediatric emergency department (PED) and its effect on return rates and masking of more serious injuries. DESIGN/METHODS: Visits to 2 PEDs from 2003 to 2010 with a diagnosis of head injury were evaluated retrospectively. Patients discharged home after a head computed tomography (CT) are the primary cohort for the study. A logistic regression model was used to analyze ondansetron's effects on the likelihood of return to the PED within 72 hours for persistent symptoms. A secondary analysis was performed on patients with a diagnoses of head injury who did not receive a head CT and were discharged. RESULTS: A total of 6311 patients had a diagnosis of head injury, had a head CT performed, and were discharged from the PED. The use of ondansetron increased significantly from 3.7% in 2003 to 22% in 2010 (P < .001). After controlling for demographic/acuity differences, receiving ondansetron in the PED was associated with a lower likelihood of returning within 72 hours (0.49, 95% confidence interval [0.26-0.92]). In patients with head injury who did not have a head CT performed and were sent home, the use of ondansetron in the PED was not associated with an increased risk of missed diagnoses. CONCLUSION: Ondansetron use in children with a CT scan who are dispositioned home is relatively safe, does not appear to mask any significant conditions, and significantly reduces return visits to the PED.


Assuntos
Antieméticos/uso terapêutico , Traumatismos Craniocerebrais/complicações , Serviço Hospitalar de Emergência/estatística & dados numéricos , Náusea/tratamento farmacológico , Ondansetron/uso terapêutico , Vômito/tratamento farmacológico , Criança , Traumatismos Craniocerebrais/diagnóstico por imagem , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Masculino , Náusea/etiologia , Alta do Paciente/estatística & dados numéricos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Vômito/etiologia
12.
Trauma Surg Acute Care Open ; 8(1): e001014, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37266305

RESUMO

Objectives: In 2020, firearm injuries surpassed automobile collisions as the leading cause of death in US children. Annual automobile fatalities have decreased during 40 years through a multipronged approach. To develop similarly targeted public health interventions to reduce firearm fatalities, there is a critical need to first characterize firearm injuries and their outcomes at a granular level. We sought to compare firearm injuries, outcomes, and types of shooters at trauma centers in four pediatric health systems across the USA. Methods: We retrospectively extracted data from each institution's trauma registry, paper and electronic health records. Study included all patients less than 19 years of age with a firearm injury between 2003 and 2018. Variables collected included demographics, intent, resources used, and emergency department and hospital disposition. Descriptive statistics were reported using medians and IQRs for continuous data and counts with percentages for categorical data. χ2 test or Fisher's exact test was conducted for categorical comparisons. Results: Our cohort (n=1008, median age 14 years) was predominantly black and male. During the study period, there was an overall increase in firearm injuries, driven primarily by increases in the South (S) site (ß=0.11 (SE 0.02), p=<0.001) in the setting of stable rates in the West and decreasing rates in the Northeast and Mid-Atlantic sites (ß=-0.15 (SE 0.04), p=0.002; ß=-0.19 (SE0.04), p=0.001). Child age, race, insurance type, resource use, injury type, and shooter type all varied by regional site. Conclusion: The incidence of firearm-related injuries seen at four sites during 15 years varied by site and region. The overall increase in firearm injuries was predominantly driven by the S site, where injuries were more often unintentional. This highlights the need for region-specific data to allow for the development of targeted interventions to impact the burden of injury.Level of Evidence: II, retrospective study.

13.
Int J Cancer ; 130(7): 1695-705, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21618507

RESUMO

Lung cancer is one of the most commonly occurring malignancies. It has been reported that mammalian target of rapamycin (mTOR) is phosphorylated in lung cancer and its activation was more frequent in tumors with overexpression of phosphatidylinositol 3-kinase (PI3K)/Akt. Therefore, dual inhibitors of PI3K/Akt and mTOR signaling could be valuable agents for treating lung cancer. In the present study, we show that fisetin, a dietary tetrahydroxyflavone inhibits cell growth with the concomitant suppression of PI3K/Akt and mTOR signaling in human nonsmall cell lung cancer (NSCLC) cells. Using autodock 4, we found that fisetin physically interacts with the mTOR complex at two sites. Fisetin treatment was also found to reduce the formation of A549 cell colonies in a dose-dependent manner. Treatment of cells with fisetin caused decrease in the protein expression of PI3K (p85 and p110), inhibition of phosphorylation of Akt, mTOR, p70S6K1, eIF-4E and 4E-BP1. Fisetin-treated cells also exhibited dose-dependent inhibition of the constituents of mTOR signaling complex such as Rictor, Raptor, GßL and PRAS40. There was an increase in the phosphorylation of AMPKα and a decrease in the phosphorylation of TSC2 on treatment of cells with fisetin. We also found that treatment of cells with mTOR inhibitor rapamycin and mTOR-siRNA caused decrease in phosphorylation of mTOR and its target proteins which were further downregulated on treatment with fisetin, suggesting that these effects are mediated in part, through mTOR signaling. Our results show that fisetin suppressed PI3K/Akt and mTOR signaling in NSCLC cells and thus, could be developed as a chemotherapeutic agent against human lung cancer.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Flavonoides/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Serina-Treonina Quinases TOR/antagonistas & inibidores , Quinases Proteína-Quinases Ativadas por AMP , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Proteínas de Transporte/antagonistas & inibidores , Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Fator de Iniciação 4E em Eucariotos/antagonistas & inibidores , Fator de Iniciação 4E em Eucariotos/metabolismo , Flavonóis , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Fosfoproteínas/antagonistas & inibidores , Fosfoproteínas/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína Companheira de mTOR Insensível à Rapamicina , Proteína Regulatória Associada a mTOR , Proteínas Quinases S6 Ribossômicas 70-kDa/antagonistas & inibidores , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Células-Tronco/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Proteína 2 do Complexo Esclerose Tuberosa , Células Tumorais Cultivadas , Proteínas Supressoras de Tumor/antagonistas & inibidores , Proteínas Supressoras de Tumor/metabolismo , Homólogo LST8 da Proteína Associada a mTOR
14.
Cancer Rep (Hoboken) ; 5(2): e1459, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34245130

RESUMO

BACKGROUND: Data are steadily accruing that demonstrate that intestinal tumors are frequently derived from multiple founding cells, resulting in tumors comprised of distinct ancestral clones that might cooperate or alternatively compete, thereby potentially impacting different phases of the disease process. AIM: We sought to determine whether tumors with a multi-ancestral architecture involving at least two distinct clones show increased tumor number, growth, progression, or resistance to drug intervention. METHODS: Mice carrying the Min allele of Apc were generated that were mosaic with only a subset of cells in the intestinal epithelium expressing an activated form of PI3K, a key regulatory kinase affecting several important cellular processes. These cells were identifiable as they fluoresced green, whereas all other cells fluoresced red. RESULTS: Cell lineage tracing revealed that many intestinal tumors from our mouse model were derived from at least two founding cells, those expressing the activated PI3K (green) and those which did not (red). Heterotypic tumors with a multi-ancestral architecture as evidenced by a mixture of green and red cells exhibited increased tumor growth and invasiveness. Clonal architecture also had an impact on tumor response to low-dose aspirin. Aspirin treatment resulted in a greater reduction of heterotypic tumors derived from multiple founding cells as compared to tumors derived from a single founding cell. CONCLUSION: These data indicate that genetically distinct tumor-founding cells can contribute to early intratumoral heterogeneity. The coevolution of the founding cells and their progeny enhances colon tumor progression and impacts the response to aspirin. These findings are important to a more complete understanding of tumorigenesis with consequences for several distinct models of tumor evolution. They also have practical implications to the clinic. Mouse models with heterogenous tumors are likely better for predicting drug efficacy as compared to models in which the tumors are highly homogeneous. Moreover, understanding how interactions among different populations in a single heterotypic tumor with a multi-ancestral architecture impact response to a single agent and combination therapies are necessary to fully develop personalized medicine.


Assuntos
Transformação Celular Neoplásica/genética , Neoplasias Intestinais/genética , Animais , Antineoplásicos/farmacologia , Carcinogênese/genética , Carcinogênese/patologia , Transformação Celular Neoplásica/patologia , Modelos Animais de Doenças , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Intestinais/tratamento farmacológico , Neoplasias Intestinais/patologia , Camundongos , Camundongos Transgênicos
15.
Cancer Metastasis Rev ; 29(3): 435-45, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20714789

RESUMO

Metastasis is the most deadly aspect of cancer and results from several interconnected processes including cell proliferation, angiogenesis, cell adhesion, migration, and invasion into the surrounding tissue. The appearance of metastases in organs distant from the primary tumor is the most destructive feature of cancer. Metastasis remains the principal cause of the deaths of cancer patients despite decades of research aimed at restricting tumor growth. Therefore, inhibition of metastasis is one of the most important issues in cancer research. Several in vitro, in vivo, and epidemiological studies have reported that the consumption of green tea may decrease cancer risk. (-)-Epigallocatechin-3-gallate, major component of green tea, has been shown to inhibit tumor invasion and angiogenesis which are essential for tumor growth and metastasis. This article summarizes the effect of green tea and its major polyphenolic compounds on cancer and metastasis against most commonly diagnosed cancer sites.


Assuntos
Metástase Neoplásica/prevenção & controle , Neoplasias/prevenção & controle , Chá , Ensaios Clínicos como Assunto , Humanos
16.
Carcinogenesis ; 31(8): 1424-33, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20530556

RESUMO

The mammalian target of rapamycin (mTOR) kinase is an important component of PTEN/PI3K/Akt signaling pathway, which is frequently deregulated in prostate cancer (CaP). Recent studies suggest that targeting PTEN/PI3K/Akt and mTOR signaling pathway could be an effective strategy for the treatment of hormone refractory CaP. Here, we show that the treatment of androgen-independent and PTEN-negative human CaP PC3 cells with fisetin, a dietary flavonoid, resulted in inhibition of mTOR kinase signaling pathway. Treatment of cells with fisetin inhibited mTOR activity and downregulated Raptor, Rictor, PRAS40 and GbetaL that resulted in loss of mTOR complexes (mTORC)1/2 formation. Fisetin also activated the mTOR repressor TSC2 through inhibition of Akt and activation of AMPK. Fisetin-mediated inhibition of mTOR resulted in hypophosphorylation of 4EBP1 and suppression of Cap-dependent translation. We also found that fisetin treatment leads to induction of autophagic-programmed cell death rather than cytoprotective autophagy as shown by small interfering RNA Beclin1-knockdown and autophagy inhibitor. Taken together, we provide evidence that fisetin functions as a dual inhibitor of mTORC1/2 signaling leading to inhibition of Cap-dependent translation and induction of autophagic cell death in PC3 cells. These results suggest that fisetin could be a useful chemotherapeutic agent in treatment of hormone refractory CaP.


Assuntos
Morte Celular/efeitos dos fármacos , Flavonoides/uso terapêutico , Fagocitose/efeitos dos fármacos , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo , Flavonóis , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Masculino , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/fisiologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR
17.
Pharm Res ; 27(6): 1128-37, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20224992

RESUMO

PURPOSE: We evaluated the chemotherapeutic effect of water extract of white cocoa tea (WCTE) against human prostate cancer (PCa) in vitro and in vivo. METHODS: Cell viability and cell cycle distribution were determined by MTT assay and flow cytometry, respectively. Western blotting was performed to determine changes in levels of various proteins. Effect of WCTE was determined in athymic nude mice implanted with PC-3 cells. RESULTS: Treatment with WCTE (100-150 microg/ml) inhibited cell proliferation, which correlated with G2/M phase arrest in PC-3 cells. WCTE treatment to PC-3 cells resulted in (1) induction of WAF1/p21 and KIP1/p27, (2) decrease in cyclins D1, D2 and E, (3) decrease in cyclin-dependent kinase (cdk) 2, 4 and 6, (4) induction of Bax and down-regulation of Bcl-2, (5) decrease in procaspase-3, -8, (6) inhibition of nuclear translocation and phosphorylation of NF-kappaB and activation of IKKalpha, and (7) inhibition of phosphorylation and degradation of IkappaBalpha. Oral administration of WCTE (0.1 and 0.2%, wt/vol) to athymic nude mice resulted in greater than 50% inhibition of tumor growth. There was a decrease in expressions of cyclin D1, Bcl-2 and p-NF-kappaB and an increase in WAF1/p21 and Bax in tumor tissues of mice. CONCLUSION: WCTE can be a useful chemotherapeutic agent against human PCa.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Camellia , Fitoterapia , Preparações de Plantas/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Chá , Animais , Apoptose/efeitos dos fármacos , Camellia/metabolismo , Inibidores de Caspase , Caspases Iniciadoras/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Quinases Ciclina-Dependentes/antagonistas & inibidores , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/antagonistas & inibidores , Ciclinas/metabolismo , Humanos , Masculino , Camundongos , Camundongos Nus , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Chá/metabolismo , Proteína X Associada a bcl-2/metabolismo
18.
Curr Opin Pediatr ; 22(3): 262-7, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20463485

RESUMO

PURPOSE OF REVIEW: To report on recent advances in quality initiatives in emergency departments (EDs), with a special focus on applicability to pediatric EDs (PED) RECENT FINDINGS: Although healthcare quality improvement has made great strides in the last couple of decades, quality improvement efforts in pediatrics have lagged behind. Over the last decade, as quality initiatives have matured in adult hospitals, there has been a downstream effect on general EDs, as system-wide clinical guidelines are usually initiated through the ED--such efforts are being reported in the literature. There is significant overlap in quality improvement efforts in adult and pediatric EDs. In this article, we review the recent relevant articles, with particular emphasis on pediatrics where appropriate. SUMMARY: There is an opportunity in pediatric emergency medicine to reduce practice variability, decrease cost and improve efficiency of care. There is an urgent need to report the successes and failures of these initiatives, so we can develop benchmarks and optimize services provided in the PED.


Assuntos
Serviço Hospitalar de Emergência/normas , Pediatria/normas , Garantia da Qualidade dos Cuidados de Saúde , Controle de Custos , Eficiência Organizacional , Serviço Hospitalar de Emergência/economia , Fidelidade a Diretrizes , Custos Hospitalares , Humanos , Assistência Centrada no Paciente/economia , Assistência Centrada no Paciente/normas , Pediatria/economia
19.
Pediatr Emerg Care ; 26(1): 26-9, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20042911

RESUMO

OBJECTIVES: In an era of pediatric emergency department (PED) overcrowding and diminishing health care resources, routine peripheral intravenous (PIV) catheter placement in the pediatric population requires evaluation because it might directly impact PED efficiency. This study aims to determine the utility of routine PIV catheter placement during phlebotomy. METHODS: Electronic medical and billing records from 2 tertiary care PEDs during 1 year in patients 21 years or younger were analyzed. Data on the presence of PIV catheter placement in the PED, subsequent PIV catheter usage, chief complaint, and demographics were tabulated and analyzed. RESULTS: During the study period, there were 131,003 PED visits analyzed and 26,776 PIV catheters placed. Of those placed, 12,475 (47%) were not used. The median age of the patients who received a PIV catheter that was not subsequently used was 36 months. The frequency of unused PIV catheters correlates with lower initial triage acuity. The highest rate of unused PIV catheter was in those 1 to 6 months old (63%), followed by that in groups younger than 1 month (57%), older than 6 to 24 months (52%), and older than 24 months (41%). CONCLUSIONS: Nearly half of the PIV catheters placed in the PED were unused. Unused PIV catheters represent an inefficient use of limited resources that could be redistributed to improve ED efficiency, flow, and resource use.


Assuntos
Cateterismo Periférico/estatística & dados numéricos , Serviço Hospitalar de Emergência/estatística & dados numéricos , Hospitais Pediátricos/estatística & dados numéricos , Adolescente , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Masculino , Flebotomia/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Tempo , Adulto Jovem
20.
Carcinogenesis ; 30(5): 808-17, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19233958

RESUMO

Lupeol, a dietary triterpene, was shown to decrease serum prostate-specific antigen levels and inhibit the tumorigenicity of prostate cancer (CaP) cells in vivo. Here, we show that Lupeol inhibits the proliferative potential of CaP cells and delineated its mechanism of action. Employing a focused microarray of human CaP-associated genes, we found that Lupeol significantly modulates the expression level of genes such as ERBB2, tissue inhibitor of metalloproteinases-3, cyclin D1 and matrix metalloproteinase (MMP)-2 that are known to be associated with proliferation and survival. A common feature of these genes is that all of them are known to either regulate or act as downstream target of beta-catenin signaling that is highly aberrant in CaP patients. Lupeol treatment significantly (1) reduced levels of beta-catenin in the cytoplasmic and nuclear fractions, (2) modulated expression levels of glycogen synthase kinase 3 beta (GSK3beta)-axin complex (regulator of beta-catenin stability), (3) decreased the expression level and enzymatic activity of MMP-2 (downstream target of beta-catenin), (4) reduced the transcriptional activation of T Cell Factor (TCF) responsive element (marker for beta-catenin signaling) in pTK-TCF-Luc-transfected cells and (5) decreased the transcriptional activation of MMP-2 gene in pGL2-MMP-2-Luc-transfected cells. Effects of Lupeol treatment on beta-catenin degradation were significantly reduced in CaP cells where axin is knocked down through small interfering RNA transfection and GSK3beta activity is blocked. Collectively, these data suggest the multitarget efficacy of Lupeol on beta-catenin-signaling network thus resulting in the inhibition CaP cell proliferation. We suggest that Lupeol could be developed as an agent for chemoprevention as well as chemotherapy of human CaP.


Assuntos
Anti-Inflamatórios/farmacologia , Divisão Celular/efeitos dos fármacos , Neoplasias da Próstata/patologia , Transdução de Sinais/fisiologia , Triterpenos/farmacologia , beta Catenina/fisiologia , Ciclina D1/genética , Regulação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Metaloproteinase 2 da Matriz/efeitos dos fármacos , Metaloproteinase 2 da Matriz/genética , Análise de Sequência com Séries de Oligonucleotídeos , Triterpenos Pentacíclicos , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Transdução de Sinais/efeitos dos fármacos , Inibidor Tecidual de Metaloproteinase-3/genética
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