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1.
J Sleep Res ; 30(6): e13386, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33991144

RESUMEN

Clarifying whether physiological sleep measures predict mortality could inform risk screening; however, such investigations should account for complex and potentially non-linear relationships among health risk factors. We aimed to establish the predictive utility of polysomnography (PSG)-assessed sleep measures for mortality using a novel permutation random forest (PRF) machine learning framework. Data collected from the years 1995 to present are from the Sleep Heart Health Study (SHHS; n = 5,734) and the Wisconsin Sleep Cohort Study (WSCS; n = 1,015), and include initial assessments of sleep and health, and up to 15 years of follow-up for all-cause mortality. We applied PRF models to quantify the predictive abilities of 24 measures grouped into five domains: PSG-assessed sleep (four measures), self-reported sleep (three), health (eight), health behaviours (four), and sociodemographic factors (five). A 10-fold repeated internal validation (WSCS and SHHS combined) and external validation (training in SHHS; testing in WSCS) were used to compute unbiased variable importance metrics and associated p values. We observed that health, sociodemographic factors, and PSG-assessed sleep domains predicted mortality using both external validation and repeated internal validation. The PSG-assessed sleep efficiency and the percentage of sleep time with oxygen saturation <90% were among the most predictive individual measures. Multivariable Cox regression also revealed the PSG-assessed sleep domain to be predictive, with very low sleep efficiency and high hypoxaemia conferring the highest risk. These findings, coupled with the emergence of new low-burden technologies for objectively assessing sleep and overnight oxygen saturation, suggest that consideration of physiological sleep measures may improve risk screening.


Asunto(s)
Sueño , Adulto , Estudios de Cohortes , Humanos , Aprendizaje Automático
2.
Gastroenterol Nurs ; 41(5): 412-423, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30272603

RESUMEN

Accurate and prompt diagnosis of celiac disease has proven difficult due to the myriad of presenting symptoms and a lack of a clear diagnostic protocol. This pilot study investigated the use of an evidence-based multimedia educational module on nurse practitioner confidence and knowledge of celiac disease. Thirteen nurse practitioners in Pennsylvania completed all study activities, which involved the use of an online pretest, learning component, an immediate post-test, along with 2 follow-up surveys. Results revealed that nurse practitioner confidence (p ≤ .05) and knowledge (p ≤ .05) levels significantly improved after participation in the educational intervention. Qualitative data also revealed that nurse practitioners are more aware of the various presentations and symptoms of celiac disease and stated that with this knowledge, their clinical practice has changed to include recognition of the various celiac disease presentations. Findings suggest that nurse practitioners are now more knowledgeable of the various presentations of celiac disease and may be more likely to consider celiac disease as a diagnosis if patients present with typical or atypical symptoms.


Asunto(s)
Enfermedad Celíaca/diagnóstico , Enfermedad Celíaca/enfermería , Competencia Clínica , Enfermeras Practicantes/educación , Autoimagen , Adulto , Enfermedad Celíaca/dietoterapia , Estudios de Cohortes , Dieta Sin Gluten , Educación de Postgrado en Enfermería , Femenino , Humanos , Masculino , Pennsylvania , Proyectos Piloto , Estudios Prospectivos
3.
Environ Sci Technol ; 51(12): 7286-7294, 2017 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-28548824

RESUMEN

Divergence in recent oil and gas related methane emission estimates between aircraft studies (basin total for a midday window) and emissions inventories (annualized regional and national statistics) indicate the need for better understanding the experimental design, including temporal and spatial alignment and interpretation of results. Our aircraft-based methane emission estimates in a major U.S. shale gas basin resolved from west to east show (i) similar spatial distributions for 2 days, (ii) strong spatial correlations with reported NG production (R2 = 0.75) and active gas well pad count (R2 = 0.81), and (iii) 2× higher emissions in the western half (normalized by gas production) despite relatively homogeneous dry gas and well characteristics. Operator reported hourly activity data show that midday episodic emissions from manual liquid unloadings (a routine operation in this basin and elsewhere) could explain ∼1/3 of the total emissions detected midday by the aircraft and ∼2/3 of the west-east difference in emissions. The 22% emission difference between both days further emphasizes that episodic sources can substantially impact midday methane emissions and that aircraft may detect daily peak emissions rather than daily averages that are generally employed in emissions inventories. While the aircraft approach is valid, quantitative, and independent, our study sheds new light on the interpretation of previous basin scale aircraft studies, and provides an improved mechanistic understanding of oil and gas related methane emissions.


Asunto(s)
Contaminantes Atmosféricos/análisis , Metano/análisis , Aeronaves , Gas Natural , Proyectos de Investigación
4.
Mol Pharm ; 13(6): 1996-2009, 2016 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-27170232

RESUMEN

Platinum (Pt) based chemotherapy is widely used to treat many types of cancer. Pt therapy faces challenges such as dose limiting toxicities, cumulative side effects, and multidrug resistance. Nanoemulsions (NEs) have tremendous potential in overcoming these challenges as they can be designed to improve circulation time, limit non-disease tissue uptake, and enhance tumor uptake by surface modification. We designed novel synthesis of three difattyacid platins, dimyrisplatin, dipalmiplatin, and distearyplatin, suitable for encapsulation in the oil core of an NE. The dimyrisplatin, dipalmiplatin, and distearyplatin were synthesized, characterized, and loaded into the oil core of our NEs, NMI-350, NMI-351, and NMI-352 respectively. Sequestration of the difattyacid platins was accomplished through high energy microfluidization. To target the NE, FA-PEG3400-DSPE was incorporated into the surface during microfluidization. The FA-NEs selectively bind the folate receptor α (FR-α) and utilize receptor mediated endocytosis to deliver Pt past cell surface resistance mechanisms. FR-α is overexpressed in a number of oncological conditions including ovarian cancer. The difattyacid platins, lipidated Gd-DTPA, and lipidated folate were characterized by nuclear magnetic resonance (NMR), mass spectrometry (MS), and elemental analysis. NEs were synthesized using high shear microfluidization process and characterized for size, zeta-potential, and loading efficiency. In vitro cytotoxicity was determined using KB-WT (Pt-sensitive) and KBCR-1000 (Pt-resistant) cancer cells and measured by MTT assay. Pharmacokinetic profiles were studied in CD-1 mice. NEs loaded with difattyacid platins are highly stable and had size distribution in the range of ∼120 to 150 nm with low PDI. Cytotoxicity data indicates the longer the fatty acid chains, the less potent the NEs. The inclusion of C6-ceramide, an apoptosis enhancer, and surface functionalization with folate molecules significantly increased in vitro potency. Pharmacokinetic studies show that the circulation time for all three difattyacid platins encapsulated in NE remained identical, thus indicating that chain length did not influence circulation time. A stable NMI-350 family of NEs were successfully designed, formulated, and characterized. The Pt-resistance in KBCR-1000 cells was reversed with the NMI-350 family. Dimyrisplatin loaded NE (NMI-350) was most potent in vitro. The NMI-350 family demonstrated identical pharmacokinetic profiles to one another and circulated much longer than cisplatin. These data indicate that NMI-350 warrants further preclinical and clinical development as a replacement for current Pt regimens especially for those afflicted with multi drug resistant cancers.


Asunto(s)
Emulsiones/administración & dosificación , Emulsiones/química , Ácido Fólico/administración & dosificación , Ácido Fólico/química , Compuestos Organoplatinos/administración & dosificación , Compuestos Organoplatinos/química , Neoplasias Ováricas/tratamiento farmacológico , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Línea Celular Tumoral , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/métodos , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Femenino , Receptor 1 de Folato/metabolismo , Gadolinio DTPA/química , Células HeLa , Humanos , Ratones , Neoplasias Ováricas/metabolismo , Tamaño de la Partícula , Polietilenglicoles/química , Nanomedicina Teranóstica/métodos
5.
J Appl Biomech ; 32(6): 599-602, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27619351

RESUMEN

This research tested a reproducible uneven walkway designed to destabilize human gait. Ten participants walked 30 times over even and uneven (7.3 × .08 m, sequentially-placed wooden blocks in a rotating pattern, 1-cm thick rubber mat) walkways. A full-body marker set and 8-camera motion capture system recorded limb kinematics. MatLab 2013b was used to calculate measures of gait stability: angular momentum, margin of stability, step width variability, CoM height, toe clearance, lateral arm swing. The minimum number of strides necessary to minimize intraparticipant variability was calculated via the interquartile range/median ratio (IMR) at 25% and 10% thresholds for each measure. A paired t test tested for significance between terrains (P < .05). The uneven walkway significantly destabilized gait as seen by increases in: coronal and sagittal plane angular momentum, step width variability, and toe clearance. We found no significant difference with the margin of stability between the 2 terrains possibly due to compensatory strategies (eg, lateral arm swing, trunk sway, step width). Recording a minimum of 10 strides per subject will keep each variable between the 25% and 10% IMR thresholds. In conclusion, the uneven walkway design significantly destabilizes human gait and at least 10 strides should be collected per subject.


Asunto(s)
Marcha/fisiología , Equilibrio Postural/fisiología , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Adulto Joven
6.
Pharm Res ; 32(8): 2753-63, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25732960

RESUMEN

PURPOSE: Platinum-based therapies are the first line treatments for most types of cancer including ovarian cancer. However, their use is associated with dose-limiting toxicities and resistance. We report initial translational studies of a theranostic nanoemulsion loaded with a cisplatin derivative, myrisplatin and pro-apoptotic agent, C6-ceramide. METHODS: The surface of the nanoemulsion is annotated with an endothelial growth factor receptor (EGFR) binding peptide to improve targeting ability and gadolinium to provide diagnostic capability for image-guided therapy of EGFR overexpressing ovarian cancers. A high shear microfludization process was employed to produce the formulation with particle size below 150 nm. RESULTS: Pharmacokinetic study showed a prolonged blood platinum and gadolinium levels with nanoemulsions in nu/nu mice. The theranostic nanoemulsions also exhibited less toxicity and enhanced the survival time of mice as compared to an equivalent cisplatin treatment. CONCLUSIONS: Magnetic resonance imaging (MRI) studies indicate the theranostic nanoemulsions were effective contrast agents and could be used to track accumulation in a tumor. The MRI study additionally indicate that significantly more EGFR-targeted theranostic nanoemulsion accumulated in a tumor than non-targeted nanoemulsuion providing the feasibility of using a targeted theranostic agent in conjunction with MRI to image disease loci and quantify the disease progression.


Asunto(s)
Antineoplásicos/administración & dosificación , Antineoplásicos/uso terapéutico , Ceramidas/administración & dosificación , Ceramidas/uso terapéutico , Receptores ErbB/efectos de los fármacos , Compuestos Organoplatinos/administración & dosificación , Compuestos Organoplatinos/uso terapéutico , Neoplasias Ováricas/tratamiento farmacológico , Nanomedicina Teranóstica/métodos , Animales , Antineoplásicos/farmacocinética , Plaquetas/metabolismo , Ceramidas/farmacocinética , Sistemas de Liberación de Medicamentos , Femenino , Gadolinio/metabolismo , Ratones , Microfluídica , Compuestos Organoplatinos/farmacocinética , Tamaño de la Partícula , Análisis de Supervivencia , Distribución Tisular
7.
Pharm Res ; 31(9): 2490-502, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24643932

RESUMEN

PURPOSE: Platinum-based chemotherapy is the treatment of choice for malignant epithelial ovarian cancers, but generalized toxicity and platinum resistance limits its use. Theranostic nanoemulsion with a novel platinum prodrug, myrisplatin, and the pro-apoptotic agent, C6-ceramide, were designed to overcome these limitations. METHODS: The nanoemulsions, including ones with an EGFR binding peptide and gadolinium, were made using generally regarded as safe grade excipients and a high shear microfluidization process. Efficacy was evaluated in ovarian cancer cells, SKOV3, A2780 and A2780CP. RESULTS: The nanoemulsion with particle size <150 nm were stable in plasma and parenteral fluids for 24 h. Ovarian cancer cells in vitro efficiently took up the non-targeted and EGFR-targeted nanoemulsions; improved cytotoxicity was observed for the these nanoemulsions with the latter showing a 50-fold drop in the IC50 in SKOV3 cells as compared to cisplatin alone. The addition of gadolinium did not affect cell viability in vitro, but showed relaxation times comparable to Magnevist(®). CONCLUSION: The myrisplatin/C6-ceramide nanoemulsion synergistically enhanced in vitro cytotoxicity. An EGFR binding peptide addition further increased in vitro cytotoxicity in EGFR positive cancer cells. The diagnostic version showed MR imaging similar to the clinically relevant Magnevist® and may be suitable as a theranostic for ovarian cancer.


Asunto(s)
Antineoplásicos/administración & dosificación , Ceramidas/administración & dosificación , Sistemas de Liberación de Medicamentos , Proteínas Fluorescentes Verdes/metabolismo , Compuestos Organoplatinos/administración & dosificación , Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/tratamiento farmacológico , Secuencia de Aminoácidos , Antineoplásicos/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ceramidas/farmacología , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Emulsiones/química , Emulsiones/metabolismo , Femenino , Gadolinio/química , Gadolinio/metabolismo , Proteínas Fluorescentes Verdes/análisis , Humanos , Imagen por Resonancia Magnética , Datos de Secuencia Molecular , Compuestos Organoplatinos/farmacología , Ovario/efectos de los fármacos , Ovario/patología , Péptidos/química , Péptidos/metabolismo
8.
AAPS PharmSciTech ; 15(3): 694-708, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24510526

RESUMEN

Nanoemulsion dosage form serves as a vehicle for the delivery of active pharmaceutical ingredients and has attracted great attention in drug delivery and pharmacotherapy. In particular, nanoemulsions act as an excellent vehicle for poorly aqueous soluble drugs, which are otherwise difficult to formulate in conventional dosage forms. Nanoemulsions are submicron emulsions composed of generally regarded as safe grade excipients. Particle size at the nanoscale and larger surface area lead to some very interesting physical properties that can be exploited to overcome anatomical and physiological barriers associated in drug delivery to the complex diseases such as cancer. Along these lines, nanoemulsions have been engineered with specific attributes such as size, surface charge, prolonged blood circulation, target specific binding ability, and imaging capability. These attributes can be tuned to assist in delivering drug/imaging agents to the specific site of interest, based on active and passive targeting mechanisms. This review focuses on the current state of nanoemulsions in the translational research and its role in targeted cancer therapy. In addition, the production, physico-chemical characterization, and regulatory aspects of nanoemulsion are addressed.


Asunto(s)
Antineoplásicos/administración & dosificación , Portadores de Fármacos , Lípidos/química , Terapia Molecular Dirigida , Nanomedicina , Nanopartículas , Neoplasias/tratamiento farmacológico , Tecnología Farmacéutica/métodos , Investigación Biomédica Traslacional , Animales , Antineoplásicos/química , Antineoplásicos/metabolismo , Química Farmacéutica , Medios de Contraste , Diagnóstico por Imagen/métodos , Emulsiones , Humanos , Lípidos/toxicidad , Neoplasias/diagnóstico , Neoplasias/metabolismo , Radiofármacos , Microambiente Tumoral
9.
Front Oncol ; 12: 850546, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35651802

RESUMEN

Glioblastoma multiforme (GBM) is an aggressive form of brain cancer with a median survival of 15 months that has remained unchanged despite advances in the standard of care. GBM cells express human cytomegalovirus (HCMV) proteins, providing a unique opportunity for targeted therapy. We utilized our UNITE (UNiversal Intracellular Targeted Expression) platform to develop a multi-antigen DNA vaccine (ITI-1001) that codes for the HCMV proteins pp65, gB, and IE-1. The UNITE platform involves lysosomal targeting technology, fusing lysosome-associated membrane protein 1 (LAMP1) with target ntigens. We demonstrate evidence of increased antigen presentation by both MHC-I and -II, delivering a robust antigen-specific CD4 and CD8 T-cell response in addition to a strong humoral response. Using a syngeneic orthotopic GBM mouse model, therapeutic treatment with the ITI-1001 vaccine resulted in ~56% survival of tumor-bearing mice. Investigation of the tumor microenvironment showed significant CD4 infiltration as well as enhanced Th1 and cytotoxic CD8 T activation. Regulatory T cells were also upregulated after ITI-1001 vaccination. In addition, tumor burden negatively correlated with activated interferon (IFN)γ+ CD4 T cells, reiterating the importance of CD4 activation in ITI-1001 efficacy and in identifying treatment responders and non-responders. Further characterization of these two groups showed high infiltration of CD3+, CD4+, and CD8+ T cells in responders compared to non-responders. Thus, we show that vaccination with HCMV antigens using the ITI-1001-UNITE platform generates strong cellular and humoral immune responses, triggering significant antitumor activity, leading to enhanced survival in a mouse model of GBM.

10.
Addiction ; 103(6): 998-1006; discussion 1007-8, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18422823

RESUMEN

AIMS: To establish whether proactively identifying all smokers in primary care populations and offering smoking cessation support is effective in increasing long-term abstinence from smoking. DESIGN: Cluster randomized controlled trial. SETTING: Twenty-four general practices in Nottinghamshire, randomized by practice to active or control intervention. PARTICIPANTS: All adult patients registered with the practices who returned a questionnaire confirming that they were current smokers (n = 6856). INTERVENTION: Participants were offered smoking cessation support by letter and those interested in receiving it were contacted and referred into National Health Service (NHS) stop smoking services if required. MEASUREMENTS: Validated abstinence from smoking, use of smoking cessation services and number of quit attempts in continuing smokers at 6 months. FINDINGS: Smokers in the intervention group were more likely than controls to report that they had used local cessation services during the study period [16.6% and 8.9%, respectively, adjusted odds ratio (OR) 2.09, 95% confidence interval (CI) 1.57-2.78], and continuing smokers (in the intervention group) were more likely to have made a quit attempt in the last 6 months (37.4% and 33.3%, respectively, adjusted OR 1.23, 95% CI 1.01-1.51). Validated point prevalence abstinence from smoking at 6 months was higher in the intervention than the control groups (3.5% and 2.5%, respectively) but the difference was not statistically significant (adjusted OR controlling for covariates: 1.64, 95% CI 0.92-2.89). CONCLUSIONS: Proactively identifying smokers who want to quit in primary care populations, and referring them to a cessation service, increased contacts with cessation services and the number of quit attempts. We were unable to detect a significant effect on long-term cessation rates, but the study was not powered to detect the kind of difference that might be expected.


Asunto(s)
Accesibilidad a los Servicios de Salud/normas , Cese del Hábito de Fumar/métodos , Prevención del Hábito de Fumar , Encuestas y Cuestionarios , Adolescente , Adulto , Métodos Epidemiológicos , Medicina Familiar y Comunitaria , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cooperación del Paciente/psicología , Fumar/psicología , Cese del Hábito de Fumar/estadística & datos numéricos , Resultado del Tratamiento
11.
Biochem J ; 402(1): 25-34, 2007 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-17040209

RESUMEN

Ns (neuroserpin) is a member of the serpin (serine protease inhibitor) gene family that is primarily expressed within the central nervous system. Its principal target protease is tPA (tissue plasminogen activator), which is thought to contribute to synaptic plasticity and to be secreted in a stimulus-dependent manner. In the present study, we demonstrate in primary neuronal cultures that Ns co-localizes in LDCVs (large dense core vesicles) with the regulated secretory protein chromogranin B. We also show that Ns secretion is regulated and can be specifically induced 4-fold by secretagogue treatment. A novel 13-amino-acid sorting signal located at the C-terminus of Ns is identified that is both necessary and sufficient to target Ns to the regulated secretion pathway. Its deletion renders Ns no longer responsive to secretagogue stimulation, whereas PAI-Ns [Ns (neuroserpin)-PAI-1 (plasminogen activator inhibitor-1) chimaera appending the last 13 residues of Ns sequence to the C-terminus of PAI-1] shifts PAI-1 secretion into a regulated secretory pathway.


Asunto(s)
Neuropéptidos/química , Inhibidores de Serina Proteinasa/química , Serpinas/química , Secuencia de Aminoácidos , Animales , Encéfalo/metabolismo , Células Cultivadas , Cromogranina B/metabolismo , Técnica del Anticuerpo Fluorescente , Humanos , Ratones , Ratones Endogámicos , Datos de Secuencia Molecular , Neuronas/metabolismo , Neuropéptidos/análisis , Neuropéptidos/metabolismo , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Vesículas Secretoras/metabolismo , Inhibidores de Serina Proteinasa/análisis , Inhibidores de Serina Proteinasa/metabolismo , Serpinas/análisis , Serpinas/metabolismo , Activador de Tejido Plasminógeno/genética , Activador de Tejido Plasminógeno/metabolismo , Neuroserpina
12.
Cancer Biol Ther ; 19(7): 554-564, 2018 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-29737910

RESUMEN

Ovarian cancer ranks fifth in cancer related deaths for women in USA. The high mortality rate associated with ovarian cancer is due to diagnosis at later stages of disease and the high recurrence rate of 60-80%. Recurrent ovarian cancers are more likely to present as multidrug resistance (MDR) leading to unfavorable response from 2nd and 3rd line chemotherapy. Nanoemulsions (NEs) are emerging as an attractive drug delivery system to overcome MDR challenges. NEs can also minimize exposure of therapeutic cargo to normal tissues potentially reducing side effects. In >80% of ovarian cancers, Folate Receptor-α (FR-α) is expressed at 10- to 100-fold higher levels than on non-pathological tissues. Therefore, folate (FA) is being evaluated as an active targeting moiety for FR-α+ ovarian cancer. To improve therapeutic outcome with reduced toxicity, we developed NMI-500, a FA targeted gadolinium (Gd) annotated NE loaded with docetaxel (DTX). NMI-500 has been developed as theranostic agents as Gd will enable physician to acquire real time pharmacodynamics data on NE + DTX accumulation in target lesions. In present study, characterization for key translational metrics of NMI-500 showed size distribution in range of 120 to 150 nm and zeta potential around -45 mV. Active targeting of FA was evaluated against FR-α+ KB cells and results demonstrated significant improvement in cell association which was surface ligand density dependent. We found that NMI-500 was able to inhibit tumor growth in a spontaneous transgenic ovarian cancer model with improved safety profile and this growth inhibition could be longitudinally followed by MRI. These results indicate NMI-500 warrants advancement to clinical trials.


Asunto(s)
Antineoplásicos/administración & dosificación , Docetaxel/administración & dosificación , Portadores de Fármacos/química , Receptor 1 de Folato/metabolismo , Neoplasias Ováricas/tratamiento farmacológico , Animales , Antineoplásicos/farmacocinética , Línea Celular Tumoral , Modelos Animales de Enfermedad , Docetaxel/farmacocinética , Portadores de Fármacos/farmacología , Emulsiones , Endocitosis , Femenino , Ácido Fólico/metabolismo , Gadolinio/química , Gadolinio/farmacología , Humanos , Imagen por Resonancia Magnética/métodos , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Imagen Molecular/métodos , Nanopartículas/química , Recurrencia Local de Neoplasia , Neoplasias Ováricas/diagnóstico por imagen , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , Nanomedicina Teranóstica/métodos
13.
J Clin Invest ; 109(12): 1571-8, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12070304

RESUMEN

Tissue-type plasminogen activator (tPA) is a highly specific serine proteinase expressed in the CNS during events that require neuronal plasticity. In this study we demonstrate that endogenous tPA mediates the progression of kainic acid-induced (KA-induced) seizures by promoting the synchronization of neuronal activity required for seizure spreading, and that, unlike KA-induced cell death, this activity is plasminogen-independent. Specifically, seizure induction by KA injection into the amygdala induces tPA activity and cell death in both hippocampi, and unilateral treatment of rats with neuroserpin, a natural inhibitor of tPA in the brain, enhances neuronal survival in both hippocampi. Inhibition of tPA within the hippocampus by neuroserpin treatment does not prevent seizure onset but instead markedly delays the progression of seizure activity in both rats and wild-type mice. In tPA-deficient mice, seizure progression is significantly delayed, and neuroserpin treatment does not further delay seizure spreading. In contrast, plasminogen-deficient mice show a pattern of seizure spreading and a response to neuroserpin that is similar to that of wild-type animals. These findings indicate that tPA acts on a substrate other than plasminogen and that the effects of neuroserpin on seizure progression and neuronal cell survival are mediated through the inhibition of tPA.


Asunto(s)
Glicoproteínas/metabolismo , Neuropéptidos/metabolismo , Activadores Plasminogénicos/metabolismo , Plasminógeno/metabolismo , Convulsiones/metabolismo , Inhibidores de Serina Proteinasa/metabolismo , Serpinas/metabolismo , Activador de Tejido Plasminógeno/metabolismo , Amígdala del Cerebelo/metabolismo , Animales , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Electrofisiología , Agonistas de Aminoácidos Excitadores/efectos adversos , Agonistas de Aminoácidos Excitadores/metabolismo , Glicoproteínas/administración & dosificación , Hipocampo/citología , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Ácido Kaínico/efectos adversos , Ácido Kaínico/metabolismo , Sistema Límbico/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neuropéptidos/administración & dosificación , Neurotoxinas/efectos adversos , Neurotoxinas/metabolismo , Plasminógeno/genética , Activadores Plasminogénicos/genética , Ratas , Ratas Sprague-Dawley , Convulsiones/inducido químicamente , Inhibidores de Serina Proteinasa/administración & dosificación , Serpinas/administración & dosificación , Activador de Tejido Plasminógeno/genética , Neuroserpina
14.
Nurse Pract ; 42(4): 40-47, 2017 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-28306660

RESUMEN

The prevalence of obesity and disability in older adults has significant public health implications. This case review discusses the benefits and risks of weight loss in older adults and outlines treatment options available to Medicare beneficiaries. The importance of preserving lean muscle mass in weight management is emphasized.


Asunto(s)
Personas con Discapacidad/estadística & datos numéricos , Obesidad/prevención & control , Pérdida de Peso , Anciano , Humanos , Medicare , Obesidad/epidemiología , Prevalencia , Medición de Riesgo , Estados Unidos/epidemiología
15.
Drug Deliv ; 23(3): 968-80, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-24901206

RESUMEN

OBJECTIVE: Ovarian cancer is a highly lethal disease in which the majority of patients eventually demonstrate multidrug resistance. Develop a novel active targeted theranostic nanomedicine designed to overcome drug efflux mechanisms, using a Generally Regarded As Safe (GRAS) grade nanoemulsion (NE) as a clinically relevant platform. MATERIALS AND METHODS: The NEs surface-functionalized with folate and gadolinium, were made using GRAS grade excipients and a high-shear microfluidization process. Efficacy was evaluated in ovarian cancer cells, SKOV3 and SKOV3TR. The NE accumulation in tumors was evaluated in SKOV3 tumor-bearing mice by magnetic resonance imaging (MRI). RESULTS AND DISCUSSION: The NE with particle size < 150 nm were stable in plasma and parenteral fluids for 24 h. Ovarian cancer cells in vitro efficiently took up the non-targeted and folate-targeted NEs; improved cytotoxicity was observed for the folate-targeted NEs showing a 270-fold drop in the IC50 in SKOV3TR cells as compared to docetaxel alone. The addition of gadolinium did not affect cell viability in vitro, but showed relaxation times comparable to Magnevist®. Folate-targeted NEs accumulated in tumors for prolonged period of time compared to Magnevist® and showed enhanced contrast compared to non-targeted NEs with MRI in SKOV3 tumor-bearing mice suggesting active targeting of NEs due to folate modification. CONCLUSIONS: A folate-targeted, theranostic NE delivers docetaxel by receptor mediated endocytosis that shows enhanced cytotoxicity capable of overcoming ABC transporter mediated taxane resistance. The diagnostic capability of the targeted nanomedicine showed enhanced contrast in tumors compared to clinically relevant MRI contrast agent Magnevist®.


Asunto(s)
Resistencia a Múltiples Medicamentos/efectos de los fármacos , Emulsiones/química , Nanopartículas/química , Neoplasias Ováricas/tratamiento farmacológico , Taxoides/administración & dosificación , Taxoides/química , Nanomedicina Teranóstica , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Hidrocarburos Aromáticos con Puentes/administración & dosificación , Hidrocarburos Aromáticos con Puentes/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Química Farmacéutica/métodos , Docetaxel , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/métodos , Femenino , Ácido Fólico/administración & dosificación , Ácido Fólico/química , Gadolinio/administración & dosificación , Gadolinio/química , Humanos , Ratones , Ratones Desnudos , Tamaño de la Partícula
16.
Biochim Biophys Acta ; 1625(2): 141-52, 2003 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-12531473

RESUMEN

The calcitonin/calcitonin gene-related peptide (CGRP) pre-mRNA is alternatively processed in a tissue-specific manner leading to the production of calcitonin mRNA in thyroid C cells and CGRP mRNA in neurons. Sequences in the human calcitonin-specific fourth exon function as an exonic splice enhancer (ESE) which is required for incorporation of exon 4 into calcitonin mRNA. Deletion of these sequences from the rat calcitonin/CGRP gene was reported to have no effect on calcitonin splicing. We demonstrate that sequences in the rat calcitonin/CGRP fourth exon act as an ESE. In addition, we observed that three proteins in HeLa nuclear extract, of apparent molecular weights of 40, 55 and 85 kDa, specifically interact with the exon 4 ESE. The 40-kDa protein is human transformer 2beta (hTra2beta), a homolog of the Drosophila splice regulator transformer 2. hTra2beta is required for calcitonin splicing in vitro, one of the first biological functions identified for hTra2beta. The 55-kDa protein is SRp55, a member of the SR family of phosphoproteins. Binding of SRp55 to an ESE required for calcitonin mRNA splicing suggests that the different levels of SRp55 present in different cell types may regulate calcitonin/CGRP alternative splicing.


Asunto(s)
Péptido Relacionado con Gen de Calcitonina/genética , Calcitonina/genética , Elementos de Facilitación Genéticos , Proteínas del Tejido Nervioso/metabolismo , Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo , Empalme del ARN , Proteínas de Unión al ARN/metabolismo , Animales , Calcitonina/biosíntesis , Calcitonina/química , Péptido Relacionado con Gen de Calcitonina/biosíntesis , Células Cultivadas , Exones , Células HeLa , Humanos , Neuronas/metabolismo , Precursores del ARN/metabolismo , ARN Mensajero/metabolismo , Ratas , Factores de Empalme Serina-Arginina , Glándula Tiroides/metabolismo , Transfección
17.
Biochim Biophys Acta ; 1625(2): 153-64, 2003 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-12531474

RESUMEN

The calcitonin/calcitonin gene-related peptide (CGRP) pre-mRNA is alternatively processed in a tissue-specific manner leading to the production of calcitonin mRNA in thyroid C cells and CGRP mRNA in neurons. A candidate calcitonin/CGRP splice regulator (CSR) isolated from rat brain was shown to inhibit calcitonin-specific splicing in vitro. CSR specifically binds to two regions in the calcitonin-specific exon 4 RNA previously demonstrated to function as a bipartate exonic splice enhancer (ESE). The two regions, A and B element, are necessary for inclusion of exon 4 into calcitonin mRNA. A novel RNA footprinting method based on the UV cross-linking assay was used to define the site of interaction between CSR and B element RNA. Base changes at the CSR binding site prevented CSR binding to B element RNA and CSR was unable to inhibit in vitro splicing of pre-mRNAs containing the mutated CSR binding site. When expressed in cells that normally produce predominantly CGRP mRNA, a calcitonin/CGRP gene containing the mutated CSR binding site expressed predominantly calcitonin mRNA. These observations demonstrate that CSR binding to the calcitonin-specific ESE regulates calcitonin/CGRP pre-mRNA splicing.


Asunto(s)
Péptido Relacionado con Gen de Calcitonina/genética , Calcitonina/genética , Elementos de Facilitación Genéticos , Precursores del ARN/metabolismo , Empalme del ARN , ARN/metabolismo , Animales , Secuencia de Bases , Sitios de Unión , Exones , Regulación de la Expresión Génica , Células HeLa , Humanos , Datos de Secuencia Molecular , Mutación , Unión Proteica , Proteínas/aislamiento & purificación , ARN/química , Precursores del ARN/química , ARN Mensajero/biosíntesis , ARN Mensajero/metabolismo , Ratas , Transfección , Células Tumorales Cultivadas
18.
Biochim Biophys Acta ; 1576(3): 287-97, 2002 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-12084575

RESUMEN

The Drosophila crooked neck (crn) gene is essential for embryogenesis and has been implicated in cell cycle progression and in pre-mRNA splicing although a direct role in either process has not been established. Here we report isolation of the human crooked neck homolog, HCRN, and provide evidence for its function in splicing. HCRN encodes an unusual protein composed largely of tetratricopeptide repeat (TPR) elements. The crooked neck protein co-localizes with the SR and Sm protein splicing factors in discrete subnuclear domains implicated in snRNP biogenesis. In vitro assembly experiments show that an 83 kDa hcrn isoform is stably recruited to splicing complexes coincident with the addition of the U4/U6.U5 tri-snRNP particle. Crooked neck activity appears essential as extracts depleted of hcrn fail to splice pre-mRNA. These and related data support the view that crooked neck is a phylogenetically conserved pre-mRNA splicing factor.


Asunto(s)
Drosophila melanogaster/genética , Proteínas/genética , Proteínas/metabolismo , Empalme del ARN , Empalmosomas/metabolismo , Secuencia de Aminoácidos , Animales , Fraccionamiento Celular , Proteínas de Drosophila/química , Proteínas de Drosophila/genética , Proteínas Fúngicas/genética , Células HeLa , Humanos , Datos de Secuencia Molecular , Proteínas Nucleares , Proteínas/química , Secuencias Repetitivas de Ácidos Nucleicos , Alineación de Secuencia , Empalmosomas/genética , Distribución Tisular
19.
Circulation ; 106(6): 740-5, 2002 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-12163437

RESUMEN

BACKGROUND: After stroke, the thrombolytic effect of tissue-type plasminogen activator (tPA) in the intravascular space is beneficial, whereas its extravascular effect on ischemic neurons is deleterious. We tested the hypothesis that neuroserpin, a natural inhibitor of tPA, reduces tPA-induced neuronal toxicity and increases its therapeutic window for treatment of embolic stroke. METHODS AND RESULTS: Rats were subjected to embolic middle cerebral artery occlusion (MCAO). Ischemic brains were treated with neuroserpin in combination with recombinant human tPA (n=7), tPA alone (n=7), or saline (n=9). Neuroserpin (20 micro L of 16 micro mol/L active neuroserpin) was intracisternally injected 3 hours and tPA (10 mg/kg) was intravenously administered 4 hours after ischemia. MRI measurements were performed to study blood brain barrier (BBB) leakage and ischemic lesion volume. Administration of tPA alone 4 hours after ischemia significantly (P<0.05) increased BBB leakage in the ischemic core measured by Gd-DTPA-enhanced MRI compared with rats treated with saline. However, treatment with neuroserpin in combination with tPA significantly (P<0.05) reduced BBB leakage, brain edema, and ischemic lesion volume compared with rats treated with tPA alone, although ischemic lesion volumes were the same in both groups before the treatment. Immunostaining revealed that MCAO resulted in reduction of neuroserpin immunoreactivity in the ipsilateral hemisphere after 2 to 6 hours of ischemia. Zymographic assay showed increased plasminogen activity in areas with BBB leakage in rats treated with tPA. CONCLUSIONS: Administration of neuroserpin after stroke is neuroprotective, seemingly because it blocks the extravascular effect of tPA, leading to subsequent decrease in stroke volume and widening of the therapeutic window for the thrombolytic effect of tPA.


Asunto(s)
Adyuvantes Farmacéuticos/uso terapéutico , Fibrinolíticos/uso terapéutico , Embolia Intracraneal/tratamiento farmacológico , Neuropéptidos/uso terapéutico , Inhibidores de Serina Proteinasa/uso terapéutico , Serpinas/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Activador de Tejido Plasminógeno/uso terapéutico , Animales , Barrera Hematoencefálica , Infarto de la Arteria Cerebral Media/metabolismo , Infarto de la Arteria Cerebral Media/patología , Infarto de la Arteria Cerebral Media/terapia , Embolia Intracraneal/metabolismo , Embolia Intracraneal/patología , Imagen por Resonancia Magnética , Masculino , Fármacos Neuroprotectores/uso terapéutico , Plasminógeno/metabolismo , Ratas , Ratas Wistar , Accidente Cerebrovascular/metabolismo , Accidente Cerebrovascular/patología , Neuroserpina
20.
Neurosurgery ; 54(2): 318-24; discussion 324-5, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14744277

RESUMEN

OBJECTIVE: Carotid endarterectomy (CEA) is effective in reducing the risk of stroke in individuals with more than 60% carotid stenosis. Carotid angioplasty and stenting (CAS) has been proffered as effective and used in treating individuals with asymptomatic carotid stenosis despite the absence of proven clinical equivalency. This randomized trial was designed to explore the hypothesis that CAS is equivalent to CEA for treating asymptomatic carotid stenosis. METHODS: A total of 85 individuals presenting with asymptomatic carotid stenosis of more than 80% were selected randomly for CAS or CEA and followed up for 48 months. RESULTS: Stenosis decreased to an average of 5% after CAS. The patency of the reconstructed artery remained satisfactory regardless of the technique, as determined by carotid ultrasonography. No major complications such as cerebral ischemia or death occurred. Procedural complications associated with CAS (n = 5) were hypotension and/or bradycardia; those concomitant with CEA (n = 3) were cervical nerve injury or complications related to general anesthesia (n = 4). Both procedures were well tolerated in the context of pain and discomfort. Hospital stay was similar in the two groups (mean, 1.1 versus 1.2 d). The occurrence of complications associated with CAS or CEA prolonged hospitalization by 3 days (mean, 4.0 versus 4.5 d). Return to full activity was achieved within 1 week by more than 85% of patients; all returned to their usual lifestyle by 2 weeks. Although hospital charges were slightly higher for CAS, costs were similar. CONCLUSION: CAS and CEA may be equally effective and safe in treating individuals with asymptomatic carotid stenosis.


Asunto(s)
Angioplastia , Estenosis Carotídea/terapia , Endarterectomía Carotidea , Stents , Anciano , Anciano de 80 o más Años , Angioplastia/efectos adversos , Endarterectomía Carotidea/efectos adversos , Estudios de Seguimiento , Hospitales Comunitarios , Humanos , Tiempo de Internación , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento
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