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1.
Nano Lett ; 24(15): 4691-4701, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38588212

RESUMO

Tumor cells exhibit heightened glucose (Glu) consumption and increased lactic acid (LA) production, resulting in the formation of an immunosuppressive tumor microenvironment (TME) that facilitates malignant proliferation and metastasis. In this study, we meticulously engineer an antitumor nanoplatform, denoted as ZLGCR, by incorporating glucose oxidase, LA oxidase, and CpG oligodeoxynucleotide into zeolitic imidazolate framework-8 that is camouflaged with a red blood cell membrane. Significantly, ZLGCR-mediated consumption of Glu and LA not only amplifies the effectiveness of metabolic therapy but also reverses the immunosuppressive TME, thereby enhancing the therapeutic outcomes of CpG-mediated antitumor immunotherapy. It is particularly important that the synergistic effect of metabolic therapy and immunotherapy is further augmented when combined with immune checkpoint blockade therapy. Consequently, this engineered antitumor nanoplatform will achieve a cooperative tumor-suppressive outcome through the modulation of metabolism and immune responses within the TME.


Assuntos
Neoplasias , Microambiente Tumoral , Humanos , Imunoterapia , Radioimunoterapia , Glucose , Glucose Oxidase , Imunossupressores , Ácido Láctico , Neoplasias/terapia , Linhagem Celular Tumoral
2.
Behav Pharmacol ; 35(4): 193-200, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38567425

RESUMO

Prepulse inhibition (PPI) is a crucial indicator of sensorimotor gating that is often impaired in neuropsychiatric diseases. Although dopamine D1 receptor agonists have been found to disrupt PPI in mice, the underlying mechanisms are not fully understood. In this study, we aimed to identify the brain regions responsible for the PPI-disruptive effect of the D1 agonist in mice. Results demonstrated that intraperitoneal administration of the selective dopamine D1 receptor agonist SKF82958 dramatically inhibited PPI, while the dopamine D1 receptor antagonist SCH23390 enhanced PPI. Additionally, local infusion of SKF82958 into the nucleus accumbens and medial prefrontal cortex disrupted PPI, but not in the ventral hippocampus. Infusion of SCH23390 into these brain regions also failed to enhance PPI. Overall, the study suggests that the nucleus accumbens and medial prefrontal cortex are responsible for the PPI-disruptive effect of dopamine D1 receptor agonists. These findings provide essential insights into the cellular and neural circuit mechanisms underlying the disruptive effects of dopamine D1 receptor agonists on PPI and may contribute to the development of novel treatments for neuropsychiatric diseases.


Assuntos
Benzazepinas , Agonistas de Dopamina , Núcleo Accumbens , Córtex Pré-Frontal , Inibição Pré-Pulso , Receptores de Dopamina D1 , Animais , Masculino , Camundongos , Benzazepinas/farmacologia , Agonistas de Dopamina/farmacologia , Antagonistas de Dopamina/farmacologia , Camundongos Endogâmicos C57BL , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/metabolismo , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Inibição Pré-Pulso/efeitos dos fármacos , Inibição Pré-Pulso/fisiologia , Receptores de Dopamina D1/agonistas , Receptores de Dopamina D1/metabolismo
3.
Nano Lett ; 22(21): 8735-8743, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36286590

RESUMO

The chemotherapy efficacy of nanodrugs is restricted by poor tumor targeting and uptake. Here, an engineered biohybrid living material (designated as EcN@HPB) is constructed by integrating paclitaxel and BAY-876 bound human serum albumin nanodrugs (HPB) with Escherichia coli Nissle 1917 (EcN). Due to the inherent tumor tropism of EcN, EcN@HPB could actively target the tumor site and competitively deprive glucose through bacterial respiration. Thus, albumin would be used as an alternative nutrient source for tumor metabolism, which significantly promotes the internalization of HPB by tumor cells. Subsequently, BAY-876 internalized along with HPB nanodrugs would further depress glucose uptake of tumor cells via inhibiting glucose transporter 1 (GLUT1). Together, the decline of glucose bioavailability of tumor cells would activate and promote the macropinocytosis in an AMP-activated protein kinase (AMPK)-dependent manner, resulting in more uptake of HPB by tumor cells and boosting the therapeutic outcome of paclitaxel.


Assuntos
Infecções por Escherichia coli , Nanopartículas , Neoplasias , Humanos , Disponibilidade Biológica , Escherichia coli/genética , Escherichia coli/metabolismo , Glucose/metabolismo , Nanopartículas/uso terapêutico , Neoplasias/tratamento farmacológico , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico
4.
J Integr Neurosci ; 21(5): 130, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-36137957

RESUMO

BACKGROUND: The efficacy of intermittent theta-burst stimulation (iTBS) and transcranial direct current stimulation (tDCS) combined with cognitive training in the treatment of post-stroke cognitive impairment (PSCI) requires further investigation. METHODS: We randomly assigned 60 patients with PSCI to receive iTBS (n = 21), tDCS (n = 19), or cognitive training alone (n = 20). Cognitive function was evaluated by the Loewenstein Occupational Therapy Cognitive Assessment (LOTCA), and the performance of activities of daily living (ADL) was assessed with the modified Barthel Index (MBI). Of these patients, 14 participated in the functional near-infrared spectroscopy (fNIRS) measurement. RESULTS: After six weeks of treatment, cognitive function improved in all three groups of PSCI patients. Compared with patients receiving only cognitive training, the cognitive function of patients in the iTBS combined with cognitive training (p = 0.003) and tDCS combined with cognitive training groups (p = 0.006) showed greater improvement. The cognitive improvement from tDCS was related to the activation of the frontopolar cortex (FPC), while the improvement of cognition by iTBS was based on the activation of the stimulation site (the dorsolateral prefrontal cortex) and some distant regions. CONCLUSIONS: Both iTBS and tDCS in addition to cognitive training appear to improve cognitive function and quality of life of patients with PSCI, compared to cognitive training alone. tDCS improved cognitive function by improving the patient's valuation, motivation, and decision-making substructures, while iTBS improved patients' assessment and decision-making abilities, improving cognitive control and, ultimately, overall cognitive function.


Assuntos
Disfunção Cognitiva , Acidente Vascular Cerebral , Estimulação Transcraniana por Corrente Contínua , Atividades Cotidianas , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/terapia , Humanos , Qualidade de Vida , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Estimulação Transcraniana por Corrente Contínua/métodos , Estimulação Magnética Transcraniana/métodos
5.
Chem Soc Rev ; 50(2): 945-985, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33226037

RESUMO

Cell primitive-based functional materials that combine the advantages of natural substances and nanotechnology have emerged as attractive therapeutic agents for cancer therapy. Cell primitives are characterized by distinctive biological functions, such as long-term circulation, tumor specific targeting, immune modulation etc. Moreover, synthetic nanomaterials featuring unique physical/chemical properties have been widely used as effective drug delivery vehicles or anticancer agents to treat cancer. The combination of these two kinds of materials will catalyze the generation of innovative biomaterials with multiple functions, high biocompatibility and negligible immunogenicity for precise cancer therapy. In this review, we summarize the most recent advances in the development of cell primitive-based functional materials for cancer therapy. Different cell primitives, including bacteria, phages, cells, cell membranes, and other bioactive substances are introduced with their unique bioactive functions, and strategies in combining with synthetic materials, especially nanoparticulate systems, for the construction of function-enhanced biomaterials are also summarized. Furthermore, foreseeable challenges and future perspectives are also included for the future research direction in this field.


Assuntos
Antineoplásicos/farmacologia , Materiais Biomiméticos/farmacologia , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/química , Materiais Biomiméticos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Neoplasias/patologia
6.
Herz ; 46(Suppl 2): 173-179, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32886131

RESUMO

BACKGROUND: This study aimed to observe the effect and potential mechanism of physiological ischemic training (PIT) in patients with ischemic cardiomyopathy. METHODS: A total of 165 patients with ischemic cardiomyopathy were randomly selected by the convenience sampling method and were divided into the control and experimental groups. The control group received conventional drug treatment, while the experimental group received additional PIT. All patients were followed up for 6 months and renin-angiotensin-aldosterone system (RAS) activity parameters and myocardial remodeling indicators were recorded. RESULTS: After the 6­month intervention, cardiac function indicators in the two groups were significantly improved compared with before intervention (all P < 0.01), but the experimental group showed significantly more improvement compared with the control group (all P < 0.01). Similarly, RAS activity parameters and myocardial remodeling indicators of the two groups were significantly reduced after intervention compared with before intervention (all P < 0.01). However, the experimental group showed significantly lower myocardial remodeling indicators than the control group (all P < 0.01). Vascular endothelial growth factor (VEGF) and nitric oxide (NO) concentrations in peripheral blood in the experimental group were significantly increased after intervention compared with before intervention (both P < 0.01). CONCLUSIONS: PIT can be applied in patients with ischemic cardiomyopathy on the basis of the original standardized drug treatment. PIT ameliorates cardiac blood flow reserve by increasing VEGF and NO concentrations in the peripheral blood, as well as by inhibiting the RAS system and myocardial remodeling. This ultimately improves the patient's cardiac function to a greater extent.


Assuntos
Cardiomiopatias , Isquemia Miocárdica , Cardiomiopatias/tratamento farmacológico , Coração , Humanos , Isquemia Miocárdica/tratamento farmacológico , Miocárdio , Fator A de Crescimento do Endotélio Vascular
7.
Nano Lett ; 19(12): 9121-9130, 2019 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-31729224

RESUMO

The broadband C3N4 semiconductor absorbs in the UV region, λ = 330-380 nm, a feature limiting its application for light-to-energy conversion. The unique surface adsorption properties of C3N4 allow, however, the binding of a photosensitizer, operating in the visible-solar spectrum to the surface of C3N4. Coupling of the energy levels of the photosensitizer with the energy levels of C3N4 allows effective photoinduced electron-transfer quenching and subsequent charge separation in the hybrid structures. Two methods to adsorb a photosensitizer on the C3N4 nanoparticles are described. One is exemplified by the adsorption of Zn(II)-protoporphyrin IX on C3N4 using π-π interactions. The second method utilizes the specific binding interactions of single-stranded nucleic acids on C3N4 and involves the binding of a Ru(II)-tris-bipyridine-modified nucleic acid on the C3N4 nanoparticles. Effective electron-transfer quenching of the photoexcited photosensitizers by C3N4 proceeds in the two hybrid systems. The two hybrid photosystems induce the effective photosensitized reduction of N,N'-dimethyl-4,4'-bipyridinium, MV2+, to MV+•, in the presence of Na2EDTA as a sacrificial electron donor. The generation of MV+• is ca. 5-fold higher as compared to the formation of MV+• in the presence of the photosensitizer alone (in the absence of C3N4). The effective generation of MV+• in the photosystems is attributed to the efficient quenching of the photosensitizers, followed by effective charge separation of the electrons in the conduction band of C3N4 and the holes in the oxidized photosensitizer. The subsequent transfer of the conduction-band electrons to MV2+ and the oxidation of Na2EDTA by the oxidized photosensitizers lead to the effective formation of MV+•. The photogenerated MV+• by the two hybrid photosystems is used to catalyze H2 evolution in the presence of Pt nanoparticle catalysts and to mediate the reduction of NADP+ to NADPH, in the presence of ferredoxin-NADP+ reductase, FNR. The ability to couple the photogenerated NADPH to drive NADP+-dependent biocatalytic transformations is demonstrated.

8.
Nano Lett ; 19(9): 6621-6628, 2019 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-31407917

RESUMO

Sequence-specific aptamers act as functional scaffolds for the assembly of photosynthetic model systems. The Ru(II)-tris-bipyridine photosensitizer is conjugated by different binding modes to the antityrosinamide aptamer to yield a set of photosensitizer-aptamer binding scaffolds. The N-methyl-N'-(3-aminopropane)-4,4'-bipyridinium electron acceptor, MV2+, is covalently linked to tyrosinamide, TA, to yield the conjugate TA-MV2+. The tyrosinamide unit in TA-MV2+ acts as a ligand for anchoring TA-MV2+ to the Ru(II)-tris-bipyridine-aptamer scaffold, generating the diversity of photosensitizer-aptamer/electron acceptor supramolecular conjugates. Effective electron transfer quenching in the photosynthetic model systems is demonstrated, and the quenching efficiencies are controlled by the structural features of the conjugates. The redox species generated by the photosensitizer-aptamer/electron acceptor supramolecular systems mediate the ferredoxin-NADP+ reductase, FNR, catalyzed synthesis of NADPH, and the Pt-nanoparticle-catalyzed evolution of hydrogen (H2). The novelty of the study rests on the unprecedented use of aptamer scaffolds as functional units for organizing photosynthetic model systems.


Assuntos
Aptâmeros de Nucleotídeos/química , Nanopartículas Metálicas/química , Modelos Químicos , Fármacos Fotossensibilizantes/química , Fotossíntese , Platina/química , Transporte de Elétrons , Ferredoxina-NADP Redutase/química , NADP/química
9.
Angew Chem Int Ed Engl ; 59(23): 9163-9170, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32125762

RESUMO

All-DNA scaffolds act as templates for the organization of photosystem I model systems. A series of DNA templates composed of ZnII -protoporphyrin IX (ZnII PPIX)-functionalized G-quadruplex conjugated to the 3'- or 5'-end of the tyrosinamide (TA) aptamer and ZnII PPIX/G-quadruplex linked to the 3'- and 5'-ends of the TA aptamer through a four-thymidine bridge. Effective photoinduced electron transfer (ET) from ZnII PPIX/G-quadruplex to bipyridinium-functionalized tyrosinamide, TA-MV2+ , bound to the TA aptamer units is demonstrated. The effectiveness of the primary ET quenching of ZnII PPIX/G-quadruplex by TA-MV2+ controls the efficiency of the generation of TA-MV+. . The photosystem-controlled formation of TA-MV+. by the different photosystems dictates the secondary activation of the ET cascade corresponding to the ferredoxin-NADP+ reductase (FNR)-catalysed reduction of NADP+ to NADPH by TA-MV+. , and the sequestered alcohol dehydrogenase catalysed reduction of acetophenone to 1-phenylethanol by NADPH.


Assuntos
Aptâmeros de Nucleotídeos/metabolismo , DNA/química , DNA/metabolismo , Quadruplex G , Modelos Biológicos , Fotossíntese , Protoporfirinas/metabolismo , Transporte de Elétrons
10.
Small ; 15(17): e1900935, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30920730

RESUMO

UiO-68 metal-organic framework nanoparticles (NMOFs) are loaded with a doxorubicin drug (fluorescent dye analogs) and locked by means of structurally engineered duplex nucleic acid structures, where one strand is covalently linked to the NMOFs and the second strand is hybridized with the anchor strand. Besides the complementarity of the second strand to the anchor sequence, it includes the complementary sequence to the microRNAs (miRNA)-21 or miRNA-221 that is specific miRNA biomarker for MCF-7 breast cancer cells or OVCAR-3 ovarian cancer cells. In the presence of the respective miRNA biomarkers, the miRNA-induced displacement of the strand associated with the anchor strand proceeds, resulting in the release of DNA/miRNA duplexes. The released duplexes are, however, engineered to be digested in the presence of exonuclease III, Exo III, a process that recycles the miRNAs and provides the autonomous amplified unlocking of the NMOFs and the release of the doxorubicin load (or the fluorescent dye analogs) even at low concentrations of miRNA. Preliminary cell experiments reveal that the respective NMOFs are unlocked by the miRNA-21 or miRNA-221, resulting in selective cytotoxicity toward MCF-7 breast cancer cells or OVCAR-3 ovarian cancer cells.


Assuntos
Sistemas de Liberação de Medicamentos , Estruturas Metalorgânicas , MicroRNAs/química , Nanomedicina/métodos , Neoplasias/tratamento farmacológico , Apoptose , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Sobrevivência Celular , Doxorrubicina/química , Feminino , Humanos , Ligantes , Células MCF-7 , MicroRNAs/metabolismo , Nanopartículas/química , Compostos Orgânicos , Neoplasias Ovarianas/tratamento farmacológico
11.
Sensors (Basel) ; 19(23)2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31795428

RESUMO

This paper features the synthesis of thrombin-responsive, nucleic acid-gated, UiO-68 metal-organic framework nanoparticles (NMOFs) loaded with the drug Apixaban or rhodamine 6G as a drug model. Apixaban acts as an inhibitor of blood clots formation. The loads in the NMOFs are locked by duplex nucleic acids that are composed of anchor nucleic acids linked to the NMOFs that are hybridized with the anti-thrombin aptamer. In the presence of thrombin, the duplex gating units are separated through the formation of thrombin-aptamer complexes. The unlocking of the NMOFs releases the drug (or the drug model). The release of the drug is controlled by the concentration of thrombin. The Apixaban-loaded NMOFs revealed improved inhibition, as compared to free Apixaban, toward blood clot formation. This is reflected by their longer time intervals for inducing clot formation and the decreased doses of the drug required to affect clots formation. The beneficial effects of the Apixaban-loaded NMOFs are attributed to the slow-release mechanism induced by the NMOFs carriers, where the inhibition of factor Xa in the blood clotting cycle retards the formation of thrombin, which slows down the release of the drug.


Assuntos
Aptâmeros de Nucleotídeos/farmacologia , Técnicas Biossensoriais , Coagulação Sanguínea/efeitos dos fármacos , Trombina/isolamento & purificação , Aptâmeros de Nucleotídeos/química , Liberação Controlada de Fármacos/efeitos dos fármacos , Inibidores do Fator Xa/química , Inibidores do Fator Xa/farmacologia , Humanos , Nanopartículas Metálicas/química , Estruturas Metalorgânicas , Pirazóis/química , Pirazóis/farmacologia , Piridonas/química , Piridonas/farmacologia , Trombina/antagonistas & inibidores
12.
Sensors (Basel) ; 19(20)2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31618848

RESUMO

Compared with conventional exoskeletons with rigid links, cable-driven upper-limb exoskeletons are light weight and have simple structures. However, cable-driven exoskeletons rely heavily on the human skeletal system for support. Kinematic modeling and control thus becomes very challenging due to inaccurate anthropomorphic parameters and flexible attachments. In this paper, the mechanical design of a cable-driven arm rehabilitation exoskeleton is proposed to accommodate human limbs of different sizes and shapes. A novel arm cuff able to adapt to the contours of human upper limbs is designed. This has given rise to an exoskeleton which reduces the uncertainties caused by instabilities between the exoskeleton and the human arm. A kinematic model of the exoskeleton is further developed by considering the inaccuracies of human-arm skeleton kinematics and attachment errors of the exoskeleton. A parameter identification method is used to improve the accuracy of the kinematic model. The developed kinematic model is finally tested with a primary experiment with an exoskeleton prototype.


Assuntos
Exoesqueleto Energizado , Movimento/fisiologia , Reabilitação do Acidente Vascular Cerebral/métodos , Extremidade Superior/fisiopatologia , Fenômenos Biomecânicos , Humanos , Desenho de Prótese
13.
Small ; 14(5)2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29205812

RESUMO

The synthesis and characterization of UiO-type metal-organic framework nanoparticles (NMOFs) composed of Zr4+ ions bridged by 2,2'-bipyridine-5,5'-dicarboxylic acid ligands and the postmodification of the NMOFs with Cu2+ ions are described. The resulting Cu2+ -modified NMOFs, Cu2+ -NMOFs, exhibit peroxidase-like catalytic activities reflected by the catalyzed oxidation of Amplex-Red to the fluorescent Resorufin by H2 O2 , the catalyzed oxidation of dopamine to aminochrome by H2 O2 , and the catalyzed generation of chemiluminescence in the presence of luminol/H2 O2 . Also, the Cu2+ -NMOFs mimic NADH peroxidase functions and catalyze the oxidation of dihydronicotinamide adenine dinucleotide, NADH, to nicotinamide adenine dinucleotide, NAD+ , in the presence of H2 O2 . The Cu2+ -NMOFs-catalyzed generation of chemiluminescence in the presence of luminol/H2 O2 is used to develop a glucose sensor by monitoring the H2 O2 formed by the aerobic oxidation of glucose to gluconic acid in the presence of glucose oxidase. Furthermore, loading the Cu2+ -NMOFs with fluorescein and activating the catalyzed generation of chemiluminescence in the presence of luminol/H2 O2 yield an efficient chemiluminescence resonance energy transfer (CRET) process to the fluorescein reflected by the activation of the fluorescence of the dye (λ = 520 nm, CRET efficiency 35%).


Assuntos
Cobre/química , Estruturas Metalorgânicas/química , Nanopartículas/química , Peroxidases/química , Catálise , Transferência de Energia , Corantes Fluorescentes/química , Luminescência , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , NAD/química , Oxirredução
14.
Opt Express ; 26(22): 28544-28559, 2018 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-30470030

RESUMO

Three dimensional (3D) body scanning has been of great interest to many fields, yet it is still a challenge to generate accurate human body models in a convenient manner. In this paper, we present an accurate 3D body scanning system based on structured light technology. A four-step phase shifting combined with Gray-code method is applied to match pixels in camera and projector planes. The calculation of 3D point coordinates are also derived. The main contribution of this paper is twofold. First, an improved registration algorithm is proposed to align point clouds reconstructed from different views. Second, we propose a graph optimization algorithm to further minimize registration errors. Experimental results demonstrate that our system can produce accurate 3D body models conveniently.


Assuntos
Imageamento Tridimensional/métodos , Luz , Imagens de Fantasmas , Fotogrametria/métodos , Algoritmos , Humanos , Processamento de Imagem Assistida por Computador
15.
IUBMB Life ; 69(7): 470-478, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28464461

RESUMO

The last 10 years have witnessed a substantial progress in understanding the neural mechanisms for the renewal of the extinguished fear memory. Based on the theory of fear extinction, exposure therapy has been developed as a typical cognitive behavioral therapy for posttraumatic stress disorder. Although the fear memory can be extinguished by repeated presentation of conditioned stimulus without unconditioned stimulus, the fear memory is not erased and tends to relapse outside of extinction context, which is referred to as renewal. Therefore, the renewal is regarded as a great obstruction interfering with the effect of exposure therapy. In recent years, there has been a great deal of studies in understanding the neurobiological underpinnings of fear renewal. These offer a foundation upon which novel therapeutic interventions for the renewal may be built. This review focuses on behavioral, anatomical and electrophysiological studies that interpret roles of the hippocampus, prelimbic cortex and amygdala as well as the connections between them for the renewal of the extinguished fear. Additionally, this review suggests the possible pathways for the renewal: (1) the prelimbic cortex may integrate contextual information from hippocampal inputs and project to the basolateral amygdala to mediate the renewal of extinguished fear memory; the ventral hippocampus may innervate the activities of the basolateral amygdala or the central amygdala directly for the renewal. © 2017 IUBMB Life, 69(7):470-478, 2017.


Assuntos
Extinção Psicológica/fisiologia , Medo/fisiologia , Vias Neurais/fisiologia , Tonsila do Cerebelo/fisiologia , Animais , Hipocampo/fisiologia , Humanos
16.
Sensors (Basel) ; 17(3)2017 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-28245553

RESUMO

RGB-D sensors have been widely used in various areas of computer vision and graphics. A good descriptor will effectively improve the performance of operation. This article further analyzes the recognition performance of shape features extracted from multi-modality source data using RGB-D sensors. A hybrid shape descriptor is proposed as a representation of objects for recognition. We first extracted five 2D shape features from contour-based images and five 3D shape features over point cloud data to capture the global and local shape characteristics of an object. The recognition performance was tested for category recognition and instance recognition. Experimental results show that the proposed shape descriptor outperforms several common global-to-global shape descriptors and is comparable to some partial-to-global shape descriptors that achieved the best accuracies in category and instance recognition. Contribution of partial features and computational complexity were also analyzed. The results indicate that the proposed shape features are strong cues for object recognition and can be combined with other features to boost accuracy.

17.
Small ; 12(6): 733-44, 2016 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-26708101

RESUMO

In this work, a ZnO based nanococktail with programmed functions is designed and synthesized for self-synergistic tumor targeting therapy. The nanococktail can actively target tumors via specific interaction of hyaluronic acid (HA) with CD44 receptors and respond to HAase-rich tumor microenvironment to induce intracellular cascade reaction for controlled therapy. The exposed cell-penetrating peptide (R8) potentiates the cellular uptake of therapeutic nanoparticles into targeted tumor cells. Then ZnO cocktail will readily degrade in acidic endo/lysosomes and induce the production of desired reactive oxygen species (ROS) in situ. The destructive ROS not only leads to serious cell damage but also triggers the on-demand drug release for precise chemotherapy, thus achieving enhanced antitumor efficiency synergistically. After tail vein injection of ZnO cocktail, a favorable tumor apoptosis rate (71.2 ± 8.2%) is detected, which is significantly superior to that of free drug, doxorubicin (12.9 ± 5.2%). Both in vitro and in vivo studies demonstrate that the tailor-made ZnO cocktail with favorable biocompatibility, promising tumor specificity, and self-synergistically therapeutic capacity opens new avenues for cancer therapy.


Assuntos
Espaço Intracelular/metabolismo , Nanopartículas/química , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Citometria de Fluxo , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/patologia , Espécies Reativas de Oxigênio/metabolismo
18.
IUBMB Life ; 68(12): 985-993, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27797140

RESUMO

5-Hydroxytryptamine 2C (5-HT2C ) receptor agonists have been suggested to possess an antipsychotic activity in several acute preclinical tests of antipsychotic drugs with low extra-pyramidal side effect liability. However, little is known about the long-term effect associated with chronic use of 5-HT2C receptor agonists. The present study examined whether repeated activation of 5-HT2C receptor with a highly selective 5-HT2C receptor agonist MK212 would induce a long-term change in its antipsychotic-like activity (either a sensitization or tolerance) in the conditioned avoidance response and MK801-induced hyperlocomotion tests. Sprague-Dawley rats were first tested under the intraperitoneal (i.p.) treatment of MK212 (0.25, 0.5, 1.0 mg/kg) for 5 consecutive days. Three days later, when all rats were injected with a low dose of MK 212 (0.25 mg/kg) and tested for avoidance responding, rats that had been pretreated with 1.0 and 0.5 mg/kg MK212 made significantly fewer avoidance responses than those that had been treated with vehicle (0.9% saline). However, this past drug exposure-induced group difference was not significant in the MK801-induced hyperlocomotion test. Overall, results from this study suggest that repeated treatment of MK212 is capable of inducing a dose-dependent sensitization of antipsychotic activity in conditioned avoidance response. The discrepancy in sensitization of MK212 in CAR and MK801-induce hyperlocomotion may be related to the different mechanism underlying the effect of MK212 in these two tests. © 2016 IUBMB Life, 68(12):985-993, 2016.


Assuntos
Antipsicóticos/administração & dosagem , Pirazinas/administração & dosagem , Agonistas do Receptor de Serotonina/administração & dosagem , Animais , Aprendizagem da Esquiva , Condicionamento Psicológico/efeitos dos fármacos , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Masculino , Atividade Motora/efeitos dos fármacos , Ratos Sprague-Dawley
19.
Neurobiol Learn Mem ; 134 Pt B: 287-93, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27481222

RESUMO

Nitric oxide (NO) is an important retrograde neuronal intracellular messenger which plays an important role in synaptic plasticity and is involved in learning and memory. However, evidence that NO is particularly important for the acquisition of contextual fear conditioning is mixed. Also, little is known about at which stages of the contextual fear conditioning does NO make its contribution. In the present study, we used 7-nitroindazole to temporarily inhibit neural nitric oxide synthase at either the pre-exposure stage or conditioning stage in a two-process paradigm and examined the potential contribution that NO makes to the contextually conditioned fear. Results showed that the expression of contextual fear memory was significantly impaired in rats treated with 7-nitroindazole (30mg/kg, i.p.) prior to the pairing of context-shock (p=0.034, n=8), but not after the conditioning phase (p=0.846, n=8). In addition, the expression of contextual fear memory and reconsolidation was not significantly impaired by 7-nitroindazole administered prior to the context pre-exposure stage or prior to another context-shock learning. These findings suggest that NO is specifically involved in the acquisition but not the consolidation, retrieval or reconsolidation of contextual fear memory.


Assuntos
Aprendizagem por Associação/efeitos dos fármacos , Condicionamento Clássico/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Medo/efeitos dos fármacos , Indazóis/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico/fisiologia , Animais , Inibidores Enzimáticos/administração & dosagem , Indazóis/administração & dosagem , Masculino , Ratos , Ratos Sprague-Dawley
20.
Small ; 11(39): 5230-42, 2015 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-26285687

RESUMO

Nanotechnology-based drug delivery has a great potential to revolutionize cancer treatment by enhancing anticancer drug efficacy and reducing drug toxicity. Here, a bioinspired nano-prodrug (BiNp) assembled by an antineoplastic peptidic derivative (FA-KLA-Hy-DOX), a folate acid (FA)-incorporated proapoptotic peptide (KLAKLAK)(2) (KLA) to doxorubicin (DOX) via an acid-labile hydrozone bond (Hy) is constructed. The hydrophobic antineoplastic agent DOX is efficiently shielded in the core of nano-prodrug. With FA targeting moieties on the surface, the obtained BiNp shows significant tumor-targeting ability and enhances the specific uptake of cancer cells. Upon the trigger by the intracellular acidic microenvironment of endosomes, the antineoplastic agent DOX is released on-demand and promotes the apoptosis of cancer cells. Simultaneously, the liberated FA-KLA can induce the dysfunction of mitochondria and evoke mitochondria-dependent apoptosis. In vitro and in vivo results show that the nano-prodrug BiNp with integrated programmed functions exhibits remarkable inhibition of tumor and achieves a maximized therapeutic efficiency with a minimized side effect.


Assuntos
Doxorrubicina/administração & dosagem , Ácido Fólico/farmacocinética , Nanocápsulas/administração & dosagem , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Pró-Fármacos/administração & dosagem , Animais , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/química , Apoptose/efeitos dos fármacos , Materiais Biomiméticos/administração & dosagem , Materiais Biomiméticos/síntese química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Sinergismo Farmacológico , Feminino , Ácido Fólico/administração & dosagem , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanocápsulas/química , Nanocápsulas/ultraestrutura , Neoplasias Experimentais/química , Neoplasias Experimentais/patologia , Pró-Fármacos/síntese química
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