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1.
Sensors (Basel) ; 24(1)2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38202880

RESUMO

Wireless sensor networks (WSNs) have emerged as a promising technology in healthcare, enabling continuous patient monitoring and early disease detection. This study introduces an innovative approach to WSN data collection tailored for disease detection through signal processing in healthcare scenarios. The proposed strategy leverages the DANA (data aggregation using neighborhood analysis) algorithm and a semi-supervised clustering-based model to enhance the precision and effectiveness of data collection in healthcare WSNs. The DANA algorithm optimizes energy consumption and prolongs sensor node lifetimes by dynamically adjusting communication routes based on the network's real-time conditions. Additionally, the semi-supervised clustering model utilizes both labeled and unlabeled data to create a more robust and adaptable clustering technique. Through extensive simulations and practical deployments, our experimental assessments demonstrate the remarkable efficacy of the proposed method and model. We conducted a comparative analysis of data collection efficiency, energy utilization, and disease detection accuracy against conventional techniques, revealing significant improvements in data quality, energy efficiency, and rapid disease diagnosis. This combined approach of the DANA algorithm and the semi-supervised clustering-based model offers healthcare WSNs a compelling solution to enhance responsiveness and reliability in disease diagnosis through signal processing. This research contributes to the advancement of healthcare monitoring systems by offering a promising avenue for early diagnosis and improved patient care, ultimately transforming the landscape of healthcare through enhanced signal processing capabilities.


Assuntos
Algoritmos , Comunicação , Humanos , Reprodutibilidade dos Testes , Análise por Conglomerados , Atenção à Saúde
2.
Artigo em Inglês | MEDLINE | ID: mdl-35182717

RESUMO

The current study is aimed to assess the ecotoxicological effects of toxic metals and seasonal shift of the physicochemical characteristics of soil in an endogeic earthworm Metaphire posthuma of industrially contaminated soil of Calcutta leather complex. The accumulation of cadmium, chromium, lead and mercury was quantitated in whole earthworms and coelomocytes. The accumulation of metals was derived to be high in the coelomocytes than whole earthworms. Morphofunctional shift in coelomocytes indicated a high level of metal toxicity in soil inhabitants. The shift in differential coelomocyte count and cellular damage including intense cytoplasmic vacuolation and membrane blebbing of coelomocytes of M. posthuma of contaminated soil were suggestive to a state of immunocompromisation in the same species. Shift in the generation of nitric oxide and activity of inducible nitric oxide synthase indicated a possible immunosuppression in earthworm. Depletion in the acetylcholinesterase activity of coelomocytes indicated neurotoxicity of metals leached from the dumped wastes in Calcutta leather complex. Integrated biomarker response based analysis was carried out to assess the biomarker potential of experimental endpoints of M. posthuma to monitor metal toxicity in soil.


Assuntos
Metais , Oligoquetos , Poluentes do Solo , Acetilcolinesterase , Animais , Biomarcadores , Índia , Metais/análise , Metais/toxicidade , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
3.
Circulation ; 112(5): 720-6, 2005 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-16043642

RESUMO

BACKGROUND: Although 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) are known to modulate endothelial function, the transcriptional mechanisms underlying these effects are incompletely understood. We hypothesized that Lung-Kruppel-like factor (LKLF/KLF2), a novel and potent regulator of endothelial gene expression, may mediate the downstream effects of statins. Here we report that statin-induced expression of endothelial NO synthase (eNOS) and thrombomodulin is KLF2 dependent. METHODS AND RESULTS: KLF2 mRNA was induced by treatment with multiple statins in a concentration-dependent manner. Multiple lines of evidence suggest that this induction is dependent on inhibition of the Rho pathway and requires de novo transcription. Furthermore, promoter deletion and mutational analyses suggest that mevastatin induced KLF2 promoter activity through a single myocyte enhancer factor binding site. Finally, small-interfering RNA-mediated knockdown of KLF2 strongly attenuated the ability of mevastatin to increase eNOS and thrombomodulin accumulation in endothelial cells. CONCLUSIONS: Taken together, these observations indicate that statin-dependent induction of eNOS and thrombomodulin requires KLF2 and thereby provides a novel molecular target for modulating endothelial function in vascular disease.


Assuntos
Endotélio Vascular/fisiologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Fatores de Transcrição Kruppel-Like/genética , Regiões 5' não Traduzidas/genética , Sequência de Bases , Células Cultivadas , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Humanos , Fatores de Transcrição Kruppel-Like/efeitos dos fármacos , Fatores de Transcrição Kruppel-Like/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Regiões Promotoras Genéticas , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Proteínas Recombinantes de Fusão/metabolismo , Trombomodulina/genética , Transfecção , Veias Umbilicais
4.
Oncotarget ; 6(34): 35830-42, 2015 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-26416422

RESUMO

The transcription factor Kruppel-like factor 2 (KLF2) displays anticarcinogenic activities but the mechanism that underlies this activity is unknown. We show here that KLF2 is markedly downregulated in human breast cancers and that its expression positively correlates with breast cancer patient survival. We show further that KLF2 suppresses tumor development by controlling the transcriptional activity of the vitamin A metabolite retinoic acid (RA). RA regulates gene transcription by activating two types of nuclear receptors: RA receptors (RARs), which inhibit tumor development, and peroxisome proliferator-activated receptor ß/δ (PPARß/δ), which promotes tumorigenesis. The partitioning of RA between these receptors is regulated by two carrier proteins: cellular retinoic acid-binding protein 2 (CRABP2), which delivers RA to RARs, and fatty acid-binding protein 5 (FABP5), which shuttles ligands to PPARß/δ. We show that KLF2 induces the expression of CRABP2 and RARγ and inhibits the expression FABP5 and PPARß/δ thereby shifting RA signaling from the pro-carcinogenic FABP5/PPARß/δ to the growth-suppressing CRABP2/RAR path. The data thus reveal that KLF2 suppresses tumor growth by controlling the transcriptional activities of RA.


Assuntos
Neoplasias da Mama/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Tretinoína/metabolismo , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Transformação Celular Neoplásica , Regulação para Baixo , Proteínas de Ligação a Ácido Graxo/antagonistas & inibidores , Feminino , Xenoenxertos , Humanos , Fatores de Transcrição Kruppel-Like/genética , Células MCF-7 , Camundongos , Camundongos Nus , Receptores do Ácido Retinoico/biossíntese , Receptores do Ácido Retinoico/genética , Transdução de Sinais , Transcrição Gênica , Receptor gama de Ácido Retinoico
5.
Mol Imaging Biol ; 14(5): 553-60, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22302178

RESUMO

PURPOSE: We compared the use of near-infrared conjugates of 2-deoxyglucose (NIR 2-DG) to 2-deoxy-2-[18F]fluoro-d-glucose (18F-FDG) for the purposes of imaging tumors, as well as response to therapy. PROCEDURES: Uptake of both 18F-FDG and NIR 2-DG within gastrointestinal stromal tumor xenografts were imaged before and after nilotinib treatment. Confocal microscopy was performed to determine NIR 2-DG distribution in tumors. RESULTS: Treatment with nilotinib resulted in a rapid reduction in 18F-FDG uptake and reduced tumor cell viability which was predictive of long-term antitumor efficacy. In contrast, optical imaging with NIR 2-DG probes was unable to differentiate control from niltonib-treated animals, and microscopic analysis revealed no change in probe distribution as a result of treatment. CONCLUSIONS: These results suggest that conjugation of large bulky fluorophores to 2-DG disrupts the facilitated transport and retention of these probes in cells. Therefore, optical imaging of NIR 2-DG probes cannot substitute for 18F-FDG positron emission tomography imaging as a biomarker of tumor cell viability and metabolism.


Assuntos
Desoxiglucose , Fluordesoxiglucose F18 , Neoplasias Gastrointestinais/diagnóstico por imagem , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Imageamento Tridimensional/métodos , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Fluorescência , Neoplasias Gastrointestinais/tratamento farmacológico , Neoplasias Gastrointestinais/patologia , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Tumores do Estroma Gastrointestinal/patologia , Humanos , Medições Luminescentes , Camundongos , Camundongos Nus , Microscopia Confocal , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Cintilografia , Espectroscopia de Luz Próxima ao Infravermelho
6.
Bioconjug Chem ; 17(1): 125-31, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16417260

RESUMO

A block copolymer of a hyperbranched poly(ethylene glycol)-like core and linear polyethylenimine (HBP) was synthesized by a facile synthetic route that included (1) a single-step cationic copolymerization of diepoxy and polyhydroxyl monomers, (2) derivatization of hydroxyl groups of the core HBPEG copolymer with either tosyl or chloromethylbenzoyl chlorides resulting in a corresponding macroinitiator, and (3) synthesis of HBPEG-block-poly(alkyl oxazolines). HBPEG-block-linear polyethyleneimine (HBP) was obtained by hydrolysis of HBPEG-block-poly(alkyl oxazolines). Linear PEI-bearing hyperbranched polycations (HBP) had lower inherent toxicity in cell culture than PEG-grafted linear polyethyleneimines (PEGLPEI). PEGLPEI formed a complex with DNA with an average diameter of 250 nm. The complexes were loosely condensed and formed aggregates and precipitates during storage. By contrast, hyperbranched polycations (HBP) formed approximately 50 nm nanocomplexes with DNA that were stable for several weeks and showed resistance to DNAse I-mediated degradation. The 'inverted' block copolymers showed several orders of magnitude higher transfection efficiency than PEGLPEI in vitro. Because of the biocompatibility and higher transfection efficiency, the 'inverted' block copolymer merits further investigation as a gene carrier.


Assuntos
Polietilenoglicóis/química , Polietilenoimina/química , Polímeros/síntese química , Transfecção/métodos , Animais , Células COS , Morte Celular/efeitos dos fármacos , Chlorocebus aethiops , DNA/administração & dosagem , DNA/química , DNA/metabolismo , Desoxirribonuclease I/metabolismo , Ensaios de Proteção de Nucleases , Plasmídeos/genética , Polietilenoglicóis/administração & dosagem , Polietilenoimina/administração & dosagem , Polímeros/administração & dosagem , Polímeros/química
7.
Bioconjug Chem ; 15(5): 960-8, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15366948

RESUMO

Novel hyperbranched dendron (HD) polymers were synthesized using a low molecular weight poly(ethyleneimine) core (BPEI). Using successive attachment of ethyleneimine moieties to the PEI core, the relative ratio of linear-to-branched structures was lowered from 1.17 to 0.70. We found that the more extensive branching of PEI enables the condensation of plasmid DNA into nanostructures with a size of 70-100 nm. The obtained complexes were stable at least for 3 weeks at 4 degrees C. The HD-DNA complexes prepared using secondary and tertiary amine-containing dendrons exerted a very low cytotoxicity in vitro during a coincubation with cells for 48 h. Using firefly luciferase as a marker of protein expression, we established that HD complexes were efficient in transfecting cells in the presence of serum. Under optimized conditions, the transfection activity at a nitrogen-to-phosphate (N/P) ratio of 6 was approximately six times higher than that of the commercially available polycationic transfection reagent. Bioluminescent imaging of in vivo gene expression using a luciferase reporter gene showed the increase of the signal in the liver and in submandibular lymph nodes in live mice. Our preliminary in vivo gene expression data demonstrates the potential of HD polymers as in vivo transfection agents that could be potentially useful for lymph node gene delivery.


Assuntos
Técnicas de Transferência de Genes , Plasmídeos/genética , Polímeros/química , Animais , Células COS , Células Cultivadas , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Terapia Genética/métodos , Humanos , Camundongos , Camundongos Nus , Tamanho da Partícula , Plasmídeos/administração & dosagem , Plasmídeos/análise , Polímeros/administração & dosagem , Polímeros/análise , Transfecção/métodos
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