Página 10 dos resultados de 1094 itens digitais encontrados em 0.053 segundos

‣ Polymeric Nanomedicine for Cancer MR Imaging and Drug Delivery

Khemtong, Chalermchai; Kessinger, Chase W.; Gao, Jinming
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Português
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Multifunctional nanomedicine is emerging as a highly integrated platform that allows for molecular diagnosis, targeted drug delivery, and simultaneous monitoring and treatment of cancer. Advances in polymer and materials science are critical for the successful development of these multi-component nanocomposites in one particulate system with such a small size confinement (<200 nm). Currently, several nanoscopic therapeutic and diagnostic systems have been translated into clinical practices. In this feature article, we will provide an up-to-date review on the development and biomedical applications of nanocomposite materials for cancer diagnosis and therapy. Overview of each functional component, i.e. polymer carriers, MR imaging agents, and therapeutic drugs will be presented. Integration of different functional components will be illustrated in several highlighted examples to demonstrate the synergy of the multifunctional nanomedicine design.

‣ An Update in Advanced Gastric Cancer: 2009

Vergo, Max; Benson, Al B.
Fonte: International Society of Gastrointestinal Oncology Publicador: International Society of Gastrointestinal Oncology
Tipo: Artigo de Revista Científica
Publicado em //2010 Português
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Overall survival in advanced gastric cancer has not changed significantly, despite two decades of multiple phase III studies. Debate is ongoing regarding whether doublet or triplet therapy is the best “standard” or platform regimen for the addition of a biologic or small-molecular targeted agents. However, in this capacity, fluoropyrimidine- and platin-based regimens are currently favored. This article will review current standards, highlight some of the more promising therapeutic agents that have emerged in the past year, and emphasize some of the molecular/genetic markers that may help guide individualized therapy.

‣ A Selective Overview of Variable Selection in High Dimensional Feature Space

Fan, Jianqing; Lv, Jinchi
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /01/2010 Português
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High dimensional statistical problems arise from diverse fields of scientific research and technological development. Variable selection plays a pivotal role in contemporary statistical learning and scientific discoveries. The traditional idea of best subset selection methods, which can be regarded as a specific form of penalized likelihood, is computationally too expensive for many modern statistical applications. Other forms of penalized likelihood methods have been successfully developed over the last decade to cope with high dimensionality. They have been widely applied for simultaneously selecting important variables and estimating their effects in high dimensional statistical inference. In this article, we present a brief account of the recent developments of theory, methods, and implementations for high dimensional variable selection. What limits of the dimensionality such methods can handle, what the role of penalty functions is, and what the statistical properties are rapidly drive the advances of the field. The properties of non-concave penalized likelihood and its roles in high dimensional statistical modeling are emphasized. We also review some recent advances in ultra-high dimensional variable selection, with emphasis on independence screening and two-scale methods.

‣ Optimization of Immunolabeled Plasmonic Nanoparticles for Cell Surface Receptor Analysis

Seekell, Kevin; Price, Hillel; Marinakos, Stella; Wax, Adam
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Português
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Noble metal nanoparticles hold great potential as optical contrast agents due to a unique feature, known as the plasmon resonance, which produces enhanced scattering and absorption at specific frequencies. The plasmon resonance also provides a spectral tunability that is not often found in organic fluorophores or other labeling methods. The ability to functionalize these nanoparticles with antibodies has led to their development as contrast agents for molecular optical imaging. In this review article, we present methods for optimizing the spectral agility of these labels. We discuss synthesis of gold nanorods, a plasmonic nanoparticle in which the plasmonic resonance can be tuned during synthesis to provide imaging within the spectral window commonly utilized in biomedical applications. We describe recent advances in our group to functionalize gold and silver nanoparticles using distinct antibodies, including EGFR, HER-2 and IGF-1, selected for their relevance to tumor imaging. Finally, we present characterization of these nanoparticle labels to verify their spectral properties and molecular specificity.

‣ The need for speed

Suhalim, Jeffrey L.; Boik, John C.; Tromberg, Bruce J.; Potma, Eric O.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Português
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One of the key enabling features of coherent Raman scattering (CRS) techniques is the dramatically improved imaging speed over conventional vibrational imaging methods. It is this enhanced imaging acquisition rate that has guided the field of vibrational microscopy into the territory of real-time imaging of live tissues. In this feature article, we review several aspects of fast vibrational imaging and discuss new applications made possible by the improved CRS imaging capabilities. In addition, we reflect on the current limitations of CRS microscopy and look ahead at several new developments towards real-time, hyperspectral vibrational imaging of biological tissues.

‣ Identifying Mechanisms of Interfacial Dynamics Using Single-Molecule Tracking

Kastantin, Mark; Walder, Robert; Schwartz, Daniel K.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Português
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The “soft” (i.e. non-covalent) interactions between molecules and surfaces are complex and highly-varied (e.g. hydrophobic, hydrogen bonding, ionic) often leading to heterogeneous interfacial behavior. Heterogeneity can arise either from spatial variation of the surface/interface itself or from molecular configurations (i.e. conformation, orientation, aggregation state, etc.). By observing adsorption, diffusion, and desorption of individual fluorescent molecules, single-molecule tracking can characterize these types of heterogeneous interfacial behavior in ways that are inaccessible to traditional ensemble-averaged methods. Moreover, the fluorescence intensity or emission wavelength (in resonance energy transfer experiments) can be used to simultaneously track molecular configuration and directly relate this to the resulting interfacial mobility or affinity. In this feature article, we review recent advances involving the use of single-molecule tracking to characterize heterogeneous molecule-surface interactions including: multiple modes of diffusion and desorption associated with both internal and external molecular configuration, Arrhenius activated interfacial transport, spatially dependent interactions, and many more.

‣ Aberrant angiogenesis: The gateway to diabetic complications

Kota, Sunil K.; Meher, Lalit K.; Jammula, Sruti; Kota, Siva K.; Krishna, S. V. S.; Modi, Kirtikumar D.
Fonte: Medknow Publications & Media Pvt Ltd Publicador: Medknow Publications & Media Pvt Ltd
Tipo: Artigo de Revista Científica
Publicado em //2012 Português
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Diabetes Mellitus is a metabolic cum vascular syndrome with resultant abnormalities in both micro- and macrovasculature. The adverse long-term effects of diabetes mellitus have been described to involve many organ systems. Apart from hyperglycemia, abnormalities of angiogenesis may cause or contribute toward many of the clinical manifestations of diabetes. These are implicated in the pathogenesis of vascular abnormalities of the retina, kidneys, and fetus, impaired wound healing, increased risk of rejection of transplanted organs, and impaired formation of coronary collaterals. A perplexing feature of the aberrant angiogenesis is that excessive and insufficient angiogenesis can occur in different organs in the same individual. The current article hereby reviews the molecular mechanisms including abnormalities in growth factors, cytokines, and metabolic derangements, clinical implications, and therapeutic options of dealing with abnormal angiogenesis in diabetes.

‣ Revisiting Thyroid Hormones in Schizophrenia

Santos, Nadine Correia; Costa, Patrício; Ruano, Dina; Macedo, António; Soares, Maria João; Valente, José; Pereira, Ana Telma; Azevedo, Maria Helena; Palha, Joana Almeida
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
Português
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Thyroid hormones are crucial during development and in the adult brain. Of interest, fluctuations in the levels of thyroid hormones at various times during development and throughout life can impact on psychiatric disease manifestation and response to treatment. Here we review research on thyroid function assessment in schizophrenia, relating interrelations between the pituitary-thyroid axis and major neurosignaling systems involved in schizophrenia's pathophysiology. These include the serotonergic, dopaminergic, glutamatergic, and GABAergic networks, as well as myelination and inflammatory processes. The available evidence supports that thyroid hormones deregulation is a common feature in schizophrenia and that the implications of thyroid hormones homeostasis in the fine-tuning of crucial brain networks warrants further research.

‣ Lipid Bodies: Inflammatory Organelles Implicated in Host-Trypanosoma cruzi Interplay during Innate Immune Responses

D'Avila, Heloisa; Toledo, Daniel A. M.; Melo, Rossana C. N.
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
Português
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The flagellated protozoa Trypanosoma cruzi is the causal agent of Chagas' disease, a significant public health issue and still a major cause of morbidity and mortality in Latin America. Acute Chagas' disease elicits a strong inflammatory response. In order to control the parasite multiplication, cells of the monocytic lineage are highly mobilized. Monocyte differentiation leads to the formation of phagocytosing macrophages, which are strongly activated and direct host defense. A distinguishing feature of Chagas' disease-triggered macrophages is the presence of increased numbers of distinct cytoplasmic organelles termed lipid bodies or lipid droplets. These organelles are actively formed in response to the parasite and are sites for synthesis and storage of inflammatory mediators. This review covers current knowledge on lipid bodies elicited by the acute Chagas' disease within inflammatory macrophages and discusses the role of these organelles in inflammation. The increased knowledge of lipid bodies in pathogenic mechanisms of infections may not only contribute to the understanding of pathogen-host interactions but may also identify new targets for intervention.

‣ Breast Tumor Angiogenesis and Tumor-Associated Macrophages: Histopathologist's Perspective

Ch'ng, Ewe Seng; Jaafar, Hasnan; Tuan Sharif, Sharifah Emilia
Fonte: SAGE-Hindawi Access to Research Publicador: SAGE-Hindawi Access to Research
Tipo: Artigo de Revista Científica
Publicado em 15/06/2011 Português
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Much progress has been made since the conceptualization of tumor angiogenesis—the induction of growth of new blood vessels by tumor—as a salient feature of clinically significant primary or metastatic cancers. From a practicing histopathologist's point of view, we appraise the application of this concept in breast cancer with particular reference to the evaluation of proangiogenic factors and the assessment of new microvessels in histopathological examination. Recently, much focus has also been centered on the active roles played by tumor-associated macrophages in relation to tumor angiogenesis. We review the literature; many data supporting this facet of tumor angiogenesis were derived from the breast cancer models. We scrutinize the large body of clinical evidence exploring the link between the tumor-associated macrophages and breast tumor angiogenesis and discuss particularly the methodology and limitations of incorporating such an assessment in histopathological examination.

‣ Mesenchymal Migration as a Therapeutic Target in Glioblastoma

Zhong, Jessie; Paul, Andre; Kellie, Stewart J.; O'Neill, Geraldine M.
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
Português
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Extensive infiltration of the surrounding healthy brain tissue is a cardinal feature of glioblastomas, highly lethal brain tumors. Deep infiltration by the glioblastoma cells renders complete surgical excision difficult and contemporary adjuvant therapies have had little impact on long-term survival. Thus, deep infiltration and resistance to irradiation and chemotherapy remain a major cause of patient mortality. Modern therapies specifically targeted to this unique aspect of glioblastoma cell biology hold significant promise to substantially improve survival rates for glioblastoma patients. In the present paper, we focus on the role of adhesion signaling molecules and the actin cytoskeleton in the mesenchymal mode of motility that characterizes invading glioblastoma cells. We then review current approaches to targeting these elements of the glioblastoma cell migration machinery and discuss other aspects of cell migration that may improve the treatment of infiltrating glioblastoma.

‣ Poly (ADP-ribose) in the pathogenesis of Parkinson's disease

Lee, Yunjong; Kang, Ho Chul; Lee, Byoung Dae; Lee, Yun-Il; Kim, Young Pil; Shin, Joo-Ho
Fonte: Korean Society for Biochemistry and Molecular Biology Publicador: Korean Society for Biochemistry and Molecular Biology
Tipo: Artigo de Revista Científica
Publicado em /08/2014 Português
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The defining feature of Parkinson’s disease is a progressive and selective demise of dopaminergic neurons. A recent report on Parkinson’s disease animal model demonstrates that poly (ADP-ribose) (PAR) dependent cell death, also named parthanatos, is accountable for selective dopaminergic neuronal loss. Parthanatos is a programmed necrotic cell death, characterized by PARP1 activation, apoptosis inducing factor (AIF) nuclear translocation, and large scale DNA fragmentation. Besides cell death regulation via interaction with AIF, PAR molecule mediates diverse cellular processes including genomic stability, cell division, transcription, epigenetic regulation, and stress granule formation. In this review, we will discuss the roles of PARP1 activation and PAR molecules in the pathological processes of Parkinson’s disease. Potential interaction between PAR molecule and Parkinson’s disease protein interactome are briefly introduced. Finally, we suggest promising points of therapeutic intervention in the pathological PAR signaling cascade to halt progression in Parkinson’s disease. [BMB Reports 2014; 47(8): 424-432]

‣ Ferritin in Adult-Onset Still's Disease: Just a Useful Innocent Bystander?

Mehta, Bella; Efthimiou, Petros
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
Português
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Background. Adult-Onset Still's Disease (AOSD) is an immune-mediated systemic disease with quotidian-spiking fever, rash, and inflammatory arthritis. Hyperferritinemia is a prominent feature, often used for screening. Methods. The key terms “ferritin” and “hyperferritinemia” were used to search PubMed and Medline and were cross-referenced with “Still's Disease.” Results. Hyperferritinemia, although nonspecific, is particularly prevalent in AOSD. While most clinicians associate ferritin with iron metabolism, this is mostly true for the H isoform and not for the L isoform that tends to increase dramatically in hyperferritenemia. In these situations, hyperferritinemia is not associated with iron metabolism and may even mask an underlying iron deficiency. We review, in systematic fashion, the current basic science and clinical literature regarding the regulation of ferritin and its use in the diagnosis and management of AOSD. Conclusion. Serum hyperferritinemia in AOSD has been described for 2 decades, although its mechanism has not yet been completely elucidated. Regulation by proinflammatory cytokines such as interleukin (IL)-1b, IL-6, IL-18, MCSF, and INF-α provides a link to the disease pathogenesis and may explain rapid resolution of hyperferritinemia after targeted treatment and inhibition of key cytokines.

‣ Olfactory Memory Impairment in Neurodegenerative Diseases

Bahuleyan, Biju; Singh, Satendra
Fonte: JCDR Research and Publications (P) Limited Publicador: JCDR Research and Publications (P) Limited
Tipo: Artigo de Revista Científica
Português
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Olfactory disorders are noted in a majority of neurodegenerative diseases, but they are often misjudged and are rarely rated in the clinical setting. Severe changes in the olfactory tests are observed in Parkinson's disease. Olfactory deficits are an early feature in Alzheimer's disease and they worsen with the disease progression. Alterations in the olfactory function are also noted after severe head injuries, temporal lobe epilepsy, multiple sclerosis, and migraine. The purpose of the present review was to discuss the available scientific knowledge on the olfactory memory and to relate its impairment with neurodegenerative diseases.

‣ Electroencephalographic Rhythms in Alzheimer's Disease

Lizio, Roberta; Vecchio, Fabrizio; Frisoni, Giovanni B.; Ferri, Raffaele; Rodriguez, Guido; Babiloni, Claudio
Fonte: SAGE-Hindawi Access to Research Publicador: SAGE-Hindawi Access to Research
Tipo: Artigo de Revista Científica
Publicado em 12/05/2011 Português
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Physiological brain aging is characterized by synapses loss and neurodegeneration that slowly lead to an age-related decline of cognition. Neural/synaptic redundancy and plastic remodelling of brain networking, also due to mental and physical training, promotes maintenance of brain activity in healthy elderly subjects for everyday life and good social behaviour and intellectual capabilities. However, age is the major risk factor for most common neurodegenerative disorders that impact on cognition, like Alzheimer's disease (AD). Brain electromagnetic activity is a feature of neuronal network function in various brain regions. Modern neurophysiological techniques, such as electroencephalography (EEG) and event-related potentials (ERPs), are useful tools in the investigation of brain cognitive function in normal and pathological aging with an excellent time resolution. These techniques can index normal and abnormal brain aging analysis of corticocortical connectivity and neuronal synchronization of rhythmic oscillations at various frequencies. The present review suggests that discrimination between physiological and pathological brain aging clearly emerges at the group level, with suggested applications also at the level of single individual. The possibility of combining the use of EEG together with biological/neuropsychological markers and structural/functional imaging is promising for a low-cost...

‣ What Is Nursing Home Quality and How Is It Measured?

Castle, Nicholas G.; Ferguson, Jamie C.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica
Publicado em /08/2010 Português
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Purpose: In this commentary, we examine nursing home quality and indicators that have been used to measure nursing home quality. Design and Methods: A brief review of the history of nursing home quality is presented that provides some context and insight into currently used quality indicators. Donabedian's structure, process, and outcome (SPO) model is used to frame the discussion. Current quality indicators and quality initiatives are discussed, including those included in the Facility Quality Indicator Profile Report, Nursing Home Compare, deficiency citations included as part of Medicare/Medicaid certification, and the Advancing Excellence Campaign. Results: Current quality indicators are presented as a mix of structural, process, and outcome measures, each of which has noted advantages and disadvantages. We speculate on steps that need to be taken in the future to address and potentially improve the quality of care provided by nursing homes, including report cards, pay for performance, market-based incentives, and policy developments in the certification process. Areas for future research are identified throughout the review. Implications: We conclude that improvements in nursing home quality have likely occurred...

‣ Diagnosis and management of Parkinson's disease dementia

Poewe, W; Gauthier, S; Aarsland, D; Leverenz, J B; Barone, P; Weintraub, D; Tolosa, E; Dubois, B
Fonte: Blackwell Publishing Ltd Publicador: Blackwell Publishing Ltd
Tipo: Artigo de Revista Científica
Publicado em /10/2008 Português
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Parkinson's disease (PD) has long been considered predominantly a motor disorder. However, its frequent association with dementia, which contributes significantly to the morbidity and mortality of the condition, is gaining increasing recognition. PD dementia (PDD) has a unique clinical profile and neuropathology, distinct from Alzheimer's disease (AD). Cholinergic deficits, a feature of both AD and PDD, underlie the rationale for cholinesterase inhibitor therapy in both conditions. In clinical practice, it is important that PDD should be recognised and appropriately treated. This review aims to outline the recently proposed clinical diagnostic criteria for PDD and to summarise the guidelines/recommendations published since 2006 on the use of cholinesterase inhibitors in the management of PDD. Although the cholinesterase inhibitor rivastigmine has recently been approved for the management of PDD, there remains a need for the development of novel therapies that can affect key mechanisms of the disease or prevent/delay patients with PD and mild cognitive impairment from progressing to PDD.

‣ From Pathways to Targets: Understanding the Mechanisms behind Polyglutamine Disease

Weber, Jonasz Jeremiasz; Sowa, Anna Sergeevna; Binder, Tina; Hübener, Jeannette
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
Português
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The history of polyglutamine diseases dates back approximately 20 years to the discovery of a polyglutamine repeat in the androgen receptor of SBMA followed by the identification of similar expansion mutations in Huntington's disease, SCA1, DRPLA, and the other spinocerebellar ataxias. This common molecular feature of polyglutamine diseases suggests shared mechanisms in disease pathology and neurodegeneration of disease specific brain regions. In this review, we discuss the main pathogenic pathways including proteolytic processing, nuclear shuttling and aggregation, mitochondrial dysfunction, and clearance of misfolded polyglutamine proteins and point out possible targets for treatment.

‣ Eosinophilic fasciitis. Case report and review of the literature.

Bennett, R M; Herron, A; Keogh, L
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /08/1977 Português
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Eosinophilic fasciitis is a recently described rheumatic disease, some 20 cases having been reported in abstract form. Previous descriptions have stressed the localized nature of skin involvement, the absence of visceral changes or Raynaud's phenomenon, an association with hypergammaglobulinaemia and eosinophilia, and a good response to corticosteroid therapy. The most conspicuous feature of this entity has been a massive thickening of the subcutaneous fascia, when an adequate (skin down to muscle) biopsy has been performed. We report another case conforming to these general features, with the exception that Raynaud's phenomenon was a prominent symptom. A critical review of the literature suggests that eosinophilic fasciitis should tentatively be regarded as a variant of scleroderma.

‣ Amyloid Oligomer Neurotoxicity, Calcium Dysregulation, and Lipid Rafts

Malchiodi-Albedi, Fiorella; Paradisi, Silvia; Matteucci, Andrea; Frank, Claudio; Diociaiuti, Marco
Fonte: SAGE-Hindawi Access to Research Publicador: SAGE-Hindawi Access to Research
Tipo: Artigo de Revista Científica
Publicado em 08/02/2011 Português
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Amyloid proteins constitute a chemically heterogeneous group of proteins, which share some biophysical and biological characteristics, the principal of which are the high propensity to acquire an incorrect folding and the tendency to aggregate. A number of diseases are associated with misfolding and aggregation of proteins, although only in some of them—most notably Alzheimer's disease (AD) and transmissible spongiform encephalopathies (TSEs)—a pathogenetic link with misfolded proteins is now widely recognized. Lipid rafts (LRs) have been involved in the pathophysiology of diseases associated with protein misfolding at several levels, including aggregation of misfolded proteins, amyloidogenic processing, and neurotoxicity. Among the pathogenic misfolded proteins, the AD-related protein amyloid β (Aβ) is by far the most studied protein, and a large body of evidence has been gathered on the role played by LRs in Aβ pathogenicity. However, significant amount of data has also been collected for several other amyloid proteins, so that their ability to interact with LRs can be considered an additional, shared feature characterizing the amyloid protein family. In this paper, we will review the evidence on the role of LRs in the neurotoxicity of huntingtin...