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1.
Cell ; 187(3): 676-691.e16, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38306983

RESUMO

Behavior relies on activity in structured neural circuits that are distributed across the brain, but most experiments probe neurons in a single area at a time. Using multiple Neuropixels probes, we recorded from multi-regional loops connected to the anterior lateral motor cortex (ALM), a circuit node mediating memory-guided directional licking. Neurons encoding sensory stimuli, choices, and actions were distributed across the brain. However, choice coding was concentrated in the ALM and subcortical areas receiving input from the ALM in an ALM-dependent manner. Diverse orofacial movements were encoded in the hindbrain; midbrain; and, to a lesser extent, forebrain. Choice signals were first detected in the ALM and the midbrain, followed by the thalamus and other brain areas. At movement initiation, choice-selective activity collapsed across the brain, followed by new activity patterns driving specific actions. Our experiments provide the foundation for neural circuit models of decision-making and movement initiation.


Assuntos
Movimento , Neurônios , Encéfalo/fisiologia , Movimento/fisiologia , Neurônios/fisiologia , Tálamo/fisiologia , Memória
2.
Proc Natl Acad Sci U S A ; 121(14): e2318521121, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38551832

RESUMO

During foraging behavior, action values are persistently encoded in neural activity and updated depending on the history of choice outcomes. What is the neural mechanism for action value maintenance and updating? Here, we explore two contrasting network models: synaptic learning of action value versus neural integration. We show that both models can reproduce extant experimental data, but they yield distinct predictions about the underlying biological neural circuits. In particular, the neural integrator model but not the synaptic model requires that reward signals are mediated by neural pools selective for action alternatives and their projections are aligned with linear attractor axes in the valuation system. We demonstrate experimentally observable neural dynamical signatures and feasible perturbations to differentiate the two contrasting scenarios, suggesting that the synaptic model is a more robust candidate mechanism. Overall, this work provides a modeling framework to guide future experimental research on probabilistic foraging.


Assuntos
Comportamento de Escolha , Recompensa , Encéfalo , Aprendizagem , Plasticidade Neuronal , Tomada de Decisões
3.
Small ; : e2312007, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38708799

RESUMO

Coordinated cell movement is a cardinal feature in tissue organization that highlights the importance of cells working together as a collective unit. Disruptions to this synchronization can have far-reaching pathological consequences, ranging from developmental disorders to tissue repair impairment. Herein, it is shown that metal oxide nanoparticles (NPs), even at low and non-toxic doses (1 and 10 µg mL-1), can perturb the coordinated epithelial cell rotation (CECR) in micropatterned human epithelial cell clusters via distinct nanoparticle-specific mechanisms. Zinc oxide (ZnO) NPs are found to induce significant levels of intracellular reactive oxygen species (ROS) to promote mitogenic activity. Generation of a new localized force field through changes in the cytoskeleton organization and an increase in cell density leads to the arrest of CECR. Conversely, epithelial cell clusters exposed to titanium dioxide (TiO2) NPs maintain their CECR directionality but display suppressed rotational speed in an autophagy-dependent manner. Thus, these findings reveal that nanoparticles can actively hijack the nano-adaptive responses of epithelial cells to disrupt the fundamental mechanics of cooperation and communication in a collective setting.

4.
Environ Sci Technol ; 57(48): 19223-19235, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37933439

RESUMO

Insights into how biological systems respond to high- and low-dose acute environmental stressors are a fundamental aspect of exposome research. However, studying the impact of low-level environmental exposure in conventional in vitro settings is challenging. This study employed a three-dimensional (3D) biomimetic microfluidic lung-on-chip (µLOC) platform and RNA-sequencing to examine the effects of two model anthropogenic engineered nanoparticles (NPs): zinc oxide nanoparticles (Nano-ZnO) and copier center nanoparticles (Nano-CCP). The airway epithelium exposed to these NPs exhibited dose-dependent increases in cytotoxicity and barrier dysregulation (dominance of the external exposome). Interestingly, even nontoxic and low-level exposure (10 µg/mL) of the epithelium compartment to Nano-ZnO triggered chemotaxis of lung fibroblasts toward the epithelium. An increase in α smooth muscle actin (α-SMA) expression and contractile activity was also observed in these cells, indicating a bystander-like adaptive response (dominance of internal exposome). Further bioinformatics and network analysis showed that a low-dose Nano-ZnO significantly induced a robust transcriptomic response and upregulated several hub genes associated with the development of lung fibrosis. We propose that Nano-ZnO, even at a no observable effect level (NOEL) dose according to conventional standards, can function as a potent nanostressor to disrupt airway epithelium homeostasis. This leads to a cascade of profibrotic events in a cross-tissue compartment fashion. Our findings offer new insights into the early acute events of respiratory harm associated with environmental NPs exposure, paving the way for better exposomic understanding of this emerging class of anthropogenic nanopollutants.


Assuntos
Expossoma , Nanopartículas , Óxido de Zinco , Biomimética , Microfluídica , Nanopartículas/toxicidade , Fibroblastos , Óxido de Zinco/toxicidade
5.
BMC Biol ; 20(1): 47, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35164755

RESUMO

BACKGROUND: Polypoidal choroidal vasculopathy (PCV), a subtype of age-related macular degeneration (AMD), is a global leading cause of vision loss in older populations. Distinct from typical AMD, PCV is characterized by polyp-like dilatation of blood vessels and turbulent blood flow in the choroid of the eye. Gold standard anti-vascular endothelial growth factor (anti-VEGF) therapy often fails to regress polypoidal lesions in patients. Current animal models have also been hampered by their inability to recapitulate such vascular lesions. These underscore the need to identify VEGF-independent pathways in PCV pathogenesis. RESULTS: We cultivated blood outgrowth endothelial cells (BOECs) from PCV patients and normal controls to serve as our experimental disease models. When BOECs were exposed to heterogeneous flow, single-cell transcriptomic analysis revealed that PCV BOECs preferentially adopted migratory-angiogenic cell state, while normal BOECs undertook proinflammatory cell state. PCV BOECs also had a repressed protective response to flow stress by demonstrating lower mitochondrial functions. We uncovered that elevated hyaluronidase-1 in PCV BOECs led to increased degradation of hyaluronan, a major component of glycocalyx that interfaces between flow stress and vascular endothelium. Notably, knockdown of hyaluronidase-1 in PCV BOEC improved mechanosensitivity, as demonstrated by a significant 1.5-fold upregulation of Krüppel-like factor 2 (KLF2) expression, a flow-responsive transcription factor. Activation of KLF2 might in turn modulate PCV BOEC migration. Barrier permeability due to glycocalyx impairment in PCV BOECs was also reversed by hyaluronidase-1 knockdown. Correspondingly, hyaluronidase-1 was detected in PCV patient vitreous humor and plasma samples. CONCLUSIONS: Hyaluronidase-1 inhibition could be a potential therapeutic modality in preserving glycocalyx integrity and endothelial stability in ocular diseases with vascular origin.


Assuntos
Hialuronoglucosaminidase , Degeneração Macular , Idoso , Corioide/irrigação sanguínea , Corioide/patologia , Células Endoteliais , Angiofluoresceinografia , Glicocálix/patologia , Humanos , Hialuronoglucosaminidase/genética , Hialuronoglucosaminidase/uso terapêutico , Degeneração Macular/tratamento farmacológico , Degeneração Macular/patologia
6.
Small ; 18(18): e2104822, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35253966

RESUMO

The intrinsic biophysical states of neutrophils are associated with immune dysfunctions in diseases. While advanced image-based biophysical flow cytometers can probe cell deformability at high throughput, it is nontrivial to couple different sensing modalities (e.g., electrical) to measure other critical cell attributes including cell viability and membrane integrity. Herein, an "optics-free" impedance-deformability cytometer for multiparametric single cell mechanophenotyping is reported. The microfluidic platform integrates hydrodynamic cell pinching, and multifrequency impedance quantification of cell size, deformability, and membrane impedance (indicative of cell viability and activation). A newly-defined "electrical deformability index" is validated by numerical simulations, and shows strong correlations with the optical cell deformability index of HL-60 experimentally. Human neutrophils treated with various biochemical stimul are further profiled, and distinct differences in multimodal impedance signatures and UMAP analysis are observed. Overall, the integrated cytometer enables label-free cell profiling at throughput of >1000 cells min-1 without any antibodies labeling to facilitate clinical diagnostics.


Assuntos
Técnicas Analíticas Microfluídicas , Microfluídica , Impedância Elétrica , Citometria de Fluxo , Células HL-60 , Humanos , Neutrófilos
7.
Small ; 18(6): e2104470, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34984816

RESUMO

Extracellular vesicles (EVs) are recognized as next generation diagnostic biomarkers due to their disease-specific biomolecular cargoes and importance in cell-cell communications. A major bottleneck in EV sample preparation is the inefficient and laborious isolation of nanoscale EVs (≈50-200 nm) from endogenous proteins in biological samples. Herein, a unique microfluidic platform is reported for EV-protein fractionation based on the principle of size exclusion chromatography (SEC). Using a novel rapid (≈20 min) replica molding technique, a fritless microfluidic SEC device (µSEC) is fabricated using thiol-ene polymer (UV glue NOA81, Young's modulus ≈1 GPa) for high pressure (up to 6 bar) sample processing. Controlled on-chip nanoliter sample plug injection (600 nL) using a modified T-junction injector is first demonstrated with rapid flow switching response time (<1.5 s). Device performance is validated using fluorescent nanoparticles (50 nm), albumin, and breast cancer cells (MCF-7)-derived EVs. As a proof-of-concept for clinical applications, EVs are directly isolated from undiluted human platelet-poor plasma using µSEC and show distinct elution profiles between EVs and proteins based on nanoparticle particle analysis (NTA), Western blot and flow cytometry analysis. Overall, the optically transparent µSEC can be readily automated and integrated with EV detection assays for EVs manufacturing and clinical diagnostics.


Assuntos
Vesículas Extracelulares , Microfluídica , Proteínas Sanguíneas/metabolismo , Cromatografia em Gel , Vesículas Extracelulares/metabolismo , Humanos , Plasma
8.
Sensors (Basel) ; 22(12)2022 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-35746238

RESUMO

Photoelectric encoders are widely used in high-precision measurement fields such as industry and aerospace because of their high precision and reliability. In order to improve the subdivision accuracy of moiré grating signals, a particle swarm optimization compensation model for grating the subdivision error of a photoelectric encoder based on parallel iteration is proposed. In the paper, an adaptive subdivision method of a particle swarm search domain based on the honeycomb structure is proposed, and a raster signal subdivision error compensation model based on the multi-swarm particle swarm optimization algorithm based on parallel iteration is established. The optimization algorithm can effectively improve the convergence speed and system accuracy of traditional particle swarm optimization. Finally, according to the subdivision error compensation algorithm, the subdivision error of the grating system caused by the sinusoidal error in the system is quickly corrected by taking advantage of the high-speed parallel processing of the FPGA pipeline architecture. The design experiment uses a 25-bit photoelectric encoder to verify the subdivision error algorithm. The experimental results show that the actual dynamic subdivision error can be reduced to ½ before compensation, and the static subdivision error can be reduced from 1.264″ to 0.487″ before detection.

9.
Anal Chem ; 93(30): 10462-10468, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34289696

RESUMO

Single-cell metabolite measurement remains highly challenging due to difficulties related to single cell isolation, metabolite detection, and identification of low levels of metabolites. Here, as a first step of the technological development, we propose a novel strategy integrating spiral inertial microfluidics and ion mobility mass spectrometry (IM-MS) for single-cell metabolite detection and identification. Cells in methanol suspension are inertially focused into a single stream in the spiral microchannel. This stream of separated cells is delivered to the nanoelectrospray needle to be lysed and ionized and subsequently analyzed in real time by IM-MS. This analytical system enables six to eight single-cell metabolic fingerprints to be collected per minute, including gas-phase collisional cross section (CCS) measurements as an additional molecular descriptor, giving increased confidence in metabolite identification. As a proof of concept, the metabolic profiles of three types of cancer cells (U2OS, HepG2, and HepG2.215) were successfully screened, and 19 distinct lipids species were identified with CCS value filtering. Furthermore, principal component analysis (PCA) showed differentiation of the three cancer cell lines, mainly due to cellular surface phospholipids. Taken together, our technology platform offers a simple and efficient method for single-cell lipid profiling, with additional ion mobility separation of lipids significantly improving the confidence toward identification of metabolites.


Assuntos
Espectrometria de Mobilidade Iônica , Microfluídica , Humanos , Lipídeos , Espectrometria de Massas , Metaboloma
10.
Small ; 17(21): e2007500, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33759381

RESUMO

3D cellular spheroids/microcarriers (100 µm-1 mm) are widely used in biomanufacturing, and non-invasive biosensors are useful to monitor cell quality in bioprocesses. In this work, a novel microfluidic approach for label-free and continuous-flow monitoring of single spheroid/microcarrier (hydrogel and Cytodex) based on electrical impedance spectroscopy using co-planar Field's metal electrodes is reported. Through numerical simulation and experimental validation, two unique impedance signatures (|ZLF | (60 kHz), |ZHF | (1 MHz)) which are optimal for spheroid growth and viability monitoring are identified. Using a closed-loop recirculation system, it is demonstrated that |ZLF | increases with breast cancer (MCF-7) spheroid biomass, while higher opacity (impedance ratio |ZHF |/|ZLF |) indicates cell death due to compromised cell membrane. Anti-cancer drug (paclitaxel)-treated spheroids also exhibit lower |ZLF | with increased cell dissociation. Interestingly, impedance characterization of adipose-derived mesenchymal stem cell differentiation on Cytodex microcarriers reveals that adipogenic cells (higher intracellular lipid content) exhibit higher impedance than osteogenic cells (more conductive due to calcium ions) for both microcarriers and single cell level. Taken together, the developed platform offers great versatility for multi-parametric analysis of spheroids/microcarriers at high throughput (≈1 particle/s), and can be readily integrated into bioreactors for long-term and remote monitoring of biomass and cell quality.


Assuntos
Células-Tronco Mesenquimais , Microfluídica , Diferenciação Celular , Impedância Elétrica , Esferoides Celulares
11.
Chemistry ; 27(43): 11167-11174, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-33871889

RESUMO

Fragmentation reactions of organotetrel chalcogenide heteroadamantane-type clusters [(PhT)4 E6 ] (T/E=Si/S (1); Si/Se; Sn/S, and Sn/Se) by addition of the corresponding sodium chalcogenide gave salts of the general formula Na3 [PhTE3 ], with T/E=Si/S (2); Si/Se (3); Sn/S (A); Sn/Se (4). Reaction of these salts with [Cu(PPh3 )3 Cl] gave a series of organotetrel-copper chalcogenide clusters [(CuPPh3 )6 (PhTE3 )2 ] with T/E=Si/S; (5), Si/Se (6), Sn/S (7) and Sn/Se (8). Compounds 5-8 share a common structural motif with two intact {PhTE3 } units coordinating a Cu6 moiety, which was previously reported with other ligands, and for the Sn and Ge congeners only. If the Sn/Se reaction system was allowed to crystallize more slowly, single crystals of compound [(CuPPh3 )6 (PhSnSe3 )3 Cu3 SnSe] (9) were obtained, which are based on a larger cluster structure. Hence, 9 might form from 8 through incorporation of additional cluster fragments. The experimentally and quantum chemically determined optical properties were compared to related clusters.

12.
FASEB J ; 34(8): 11133-11142, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32627899

RESUMO

Vitamin D deficiency is a major public health problem worldwide, linked to several chronic diseases including cardiovascular diseases. While immunomodulatory effects of vitamin D on monocytes have been reported in cardiovascular and metabolic diseases, there is limited understanding on monocyte phenotype in healthy individuals with suboptimal vitamin D levels and without any clinical diseases. In this work, we performed label-free, microfluidic isolation of monocytes, and characterized their functional phenotype using flow cytometry and in vitro vascular models in healthy subjects with (n = 7) and without vitamin D deficiency (n = 16). Vitamin D deficient (VitD-Def) subjects (25(OH)D3 level < 26 ng/mL) expressed significant downregulation of vitamin D receptor (VDR) on monocytes as compared to controls (P < .0001), and VDR expression was well-associated with serum 25(OH)D3 levels. Increased monocyte-platelet aggregates (MPA), a marker for platelet activation, were also observed in VitD-Def subjects (P < .05) which suggests a pro-inflammatory monocyte phenotype. Monocyte adhesion to endothelial cells, an early-stage atherosclerosis event, was also higher in VitD-Def individuals, and inversely correlated to serum 25(OH)D3 level (P < .05). Taken together, these results indicate the pro-inflammatory state and atherogenic potential of monocytes in VitD-Def healthy subjects, and propound the use of vitamin D supplementation as a prospective immunomodulatory and anti-inflammatory therapy in atherosclerosis.


Assuntos
Plaquetas/fisiologia , Adesão Celular/fisiologia , Células Endoteliais/fisiologia , Monócitos/fisiologia , Deficiência de Vitamina D/fisiopatologia , Vitamina D/metabolismo , Aterosclerose/metabolismo , Aterosclerose/patologia , Plaquetas/metabolismo , Células Cultivadas , Suplementos Nutricionais , Regulação para Baixo/fisiologia , Células Endoteliais/metabolismo , Feminino , Voluntários Saudáveis , Células Endoteliais da Veia Umbilical Humana , Humanos , Inflamação/metabolismo , Inflamação/patologia , Masculino , Monócitos/metabolismo , Ativação Plaquetária/fisiologia , Receptores de Calcitriol/metabolismo , Deficiência de Vitamina D/metabolismo
13.
Small ; 16(34): e2003757, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32686344

RESUMO

Exogenous sources of amino acids are essential nutrients to fuel cancer growth. Here, the increased demand for amino acid displayed by cancer cells is unconventionally exploited as a design principle to replete cancer cells with apoptosis inducing nanoscopic porous amino acid mimics (Nano-PAAM). A small library consisting of nine essential amino acids nanoconjugates (30 nm) are synthesized, and the in vitro anticancer activity is evaluated. Among the Nano-PAAMs, l-phenylalanine functionalized Nano-PAAM (Nano-pPAAM) has emerged as a novel nanotherapeutics with excellent intrinsic anticancer and cancer-selective properties. The therapeutic efficacy of Nano-pPAAM against a panel of human breast, gastric, and skin cancer cells could be ascribed to the specific targeting of the overexpressed human large neutral amino acid transporter SLC7A5 (LAT-1) in cancer cells, and its intracellular reactive oxygen species (ROS) inducing properties of the nanoporous core. At the mechanistic level, it is revealed that Nano-pPAAM could activate both the extrinsic and intrinsic apoptosis pathways to exert a potent "double-whammy" anticancer effect. The potential clinical utility of Nano-pPAAM is further investigated using an MDA-MB-231 xenograft in NOD scid gamma mice, where an overall suppression of tumor growth by 60% is achieved without the aid of any drugs or application of external stimuli.


Assuntos
Antineoplásicos , Aminoácidos , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Linhagem Celular Tumoral , Camundongos , Nanoconjugados , Porosidade
14.
Sensors (Basel) ; 20(20)2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33066075

RESUMO

In order to improve the performance in the practical engineering applications including so called low-speed video tracking and large-angle swing scanning imaging at the same time for a three-axis universal inertially stabilized platform (UISP), we propose an adaptive nonsingular fast terminal sliding mode control (ANFTSMC) strategy subjected to the uncertain disturbances and input saturation constraints. First of all, a second-order dynamic model is established with uncertain disturbances and input saturation constraints. Secondly, a nonsingular fast terminal sliding mode controller (NTSMC) is constructed to ensure the system error converges to zero fast in a finite time; meanwhile, a novel reaching law based on a modified normal distribution function is designed to adjust the control gain. Thirdly, an adaptive control law is designed to online estimate the parameters of the lumped uncertain disturbances. Additionally, the stability of the control system is proved by Lyapunov theory. Finally, extensive comparative simulations and experiments are carried out, the results comprehensively show the effectiveness and superiority of the proposed control method, which can accelerate convergence, weaken the chattering, and has the better control accuracy and robust performance both in the low-speed tracking and large-angle swing scanning applications. Moreover, the exact dynamic model and the prior knowledge of the upper bounds of the disturbances are not required during the procedure of the controller design, which make it have more extensive application value in practical engineering.

15.
Virol J ; 16(1): 38, 2019 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-30917832

RESUMO

BACKGROUND: Tobacco production in China has been affected by plant viruses with Milk vetch dwarf virus (MDV) as a recent invader posing serious concern. According to most of the studies, MDV mainly infects hosts from Fabaceae family but in our previous study we reported its infection in tobacco plant (Nicotiana tabacum L.) in Shandong province. FINDINGS: In current study (2016-2017), tobacco plants (Nicotiana tabacum) with severe stunting, yellowing and axillary bunch of new leaves were observed in Zhengning, Gansu province. Isolate GSZN yielded into eight genomic circular single-stranded DNA components while no alphasatellite DNA was obtained. High percent identity of this isolate was recorded in overall nucleotide and amino acid assembly with reported MDV isolates worldwide. Phylogenetic analysis fetched into a separate sub-clade comprising of new isolate along with other tobacco infecting isolates of MDV. While recombination was predicted in DNA-C encoding Clink protein and DNA-U1, which may attribute towards the potential host-shifting phenomenon and ability of this virus to expand its host range. CONCLUSION: To our knowledge this is the first full genome annotation of a Nanovirus, infecting tobacco in natural field conditions, also this is the first extended analysis on host-shifting behavior of MDV.


Assuntos
Genoma Viral , Nanovirus/genética , Nicotiana/virologia , Análise de Sequência de DNA , Astrágalo/virologia , China , DNA Viral/genética , Interações entre Hospedeiro e Microrganismos , Filogenia , Doenças das Plantas/virologia
16.
Cereb Cortex ; 28(2): 612-624, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28057722

RESUMO

Accurate heading perception relies on visual information integrated across a wide field, that is, optic flow. Numerous computational studies have speculated how local visual information might be pooled by the brain to compute heading, but these hypotheses lack direct neurophysiological support. In the current study, we instructed human and monkey subjects to judge heading directions based on global optic flow. We showed that a local perturbation cue applied within only a small part of the visual field could bias the subjects' heading judgments, and shift the neuronal tuning in the macaque middle temporal (MT) area at the same time. Electrical microstimulation in MT significantly biased the animals' heading judgments predictable from the tuning of the stimulated neurons. Masking the visual stimuli within these neurons' receptive fields could not remove the stimulation effect, indicating a sufficient role of the MT signals pooled by downstream neurons for global heading estimation. Interestingly, this pooling is not homogeneous because stimulating neurons with excitatory surrounds produced relatively larger effects than stimulating neurons with inhibitory surrounds. Thus our data not only provide direct causal evidence, but also new insights into the neural mechanisms of pooling local motion information for global heading estimation.


Assuntos
Movimentos Oculares/fisiologia , Percepção de Movimento/fisiologia , Estimulação Luminosa/métodos , Lobo Temporal/fisiologia , Animais , Estimulação Elétrica/métodos , Humanos , Macaca mulatta , Microeletrodos
17.
Anal Chem ; 90(24): 14535-14542, 2018 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-30426739

RESUMO

Monocytes and platelets play key roles in atherosclerosis and thrombosis, and circulating monocyte-platelet aggregates (MPA) in blood have been widely proposed as surrogate biomarkers for cardiovascular risk stratification and monitoring antiplatelet therapies. However, conventional MPA characterization is based on whole-blood fixation and flow cytometry analysis which adversely affect cell viability and detection accuracy due to significant leukocyte and platelet contaminations. Herein, we introduce a rapid and label-free microfluidic approach for complete size-based fractionation of peripheral blood mononuclear cells (PBMCs) into monocytes, lymphocytes, and platelets. The developed biochip enables gentle sorting of intact MPA in the enriched monocytes with efficient depletion of lymphocytes and platelets for accurate MPA quantification. We first compared the developed microfluidic technology (dean flow fractionation, DFF) with standard magnetic negative isolation (MACS) and observed that DFF-sorted monocytes had similar viability, purity, and key immune functions (phagocytosis, macrophage differentiation) as MACS-sorted monocytes. As proof of concept for diabetes testing, we isolated and characterized monocytes/MPA from a cohort of healthy ( n = 5) and type 2 diabetes mellitus (T2DM) subjects ( n = 8) in PBMCs and DFF-sorted monocytes. High-speed imaging, immunofluorescence, and flow cytometry analysis clearly indicated higher levels of MPA in T2DM patients ( P < 0.05) with enhanced MPA detection sensitivity in DFF-sorted monocytes ( P < 0.05). Taken together, the developed DFF technology greatly facilitates high-throughput (∼130 µL min-1) label-free isolation of monocyte/MPA from PBMCs and can be further developed into a clinical tool for point-of-care cardiovascular risk stratification in metabolic disorders including T2DM.


Assuntos
Plaquetas/citologia , Microfluídica/métodos , Monócitos/citologia , Plaquetas/metabolismo , Estudos de Casos e Controles , Diferenciação Celular , Citocinas/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Citometria de Fluxo , Humanos , Leucócitos Mononucleares/citologia , Microscopia de Fluorescência , Monócitos/metabolismo , Fagocitose
18.
Cell Physiol Biochem ; 47(4): 1365-1376, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29929188

RESUMO

BACKGROUND/AIMS: To explore the potential role of qiliqiangxin (QLQX) A traditional Chinese medicine and the involvement of angiotensin II receptor type 1 (AGTR1) and transient receptor potential vanilloid 1 (TRPV1) in diabetic mouse cardiac function. METHODS: Intragastric QLQX was administered for 5 weeks after streptozotocin (STZ) treatment. Additionally, Intraperitoneal injections of angiotensin II (Ang II) or intragastric losartan (Los) were administered to assess the activities of AGTR1 and TRPV1. Two-dimensional echocardiography and tissue histopathology were used to assess cardiac function Western blot was used to detect the autophagic biomarkers Such as light chain 3 P62 and lysosomal-associated membrane protein 2 And transmission electron microscopy was used to count the number of autophagosomes. RESULTS: Decreased expression of TRPV1 and autophagic hallmarks and reduced numbers of autophagolysosomes as well as increased expression of angiotensin converting enzyme 1 and AGTR1 were observed in diabetic hearts. Blocking AGTR1 with Los mimicked the QLQX-mediated improvements in cardiac function Alleviated myocardial fibrosis and enabled autophagy Whereas Ang II abolished the beneficial effects of QLQX in wild type diabetic mice but not in TRPV1-/- diabetic mice. CONCLUSIONS: QLQX may improve diabetic cardiac function by regulating AGTR1/ TRPV1-mediated autophagy in STZ-induced diabetic mice.


Assuntos
Autofagia/efeitos dos fármacos , Diabetes Mellitus Experimental/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Miocárdio/metabolismo , Receptor Tipo 1 de Angiotensina/metabolismo , Canais de Cátion TRPV/metabolismo , Animais , Autofagia/genética , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patologia , Eletrocardiografia , Testes de Função Cardíaca , Camundongos , Camundongos Knockout , Miocárdio/patologia , Receptor Tipo 1 de Angiotensina/genética , Canais de Cátion TRPV/genética
19.
BMC Plant Biol ; 18(1): 5, 2018 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-29301488

RESUMO

BACKGROUND: Alternative splicing (AS) is an important post-transcriptional process. It has been suggested that most AS events are subject to tissue-specific regulation. However, the global dynamics of AS in different tissues are poorly explored. RESULTS: To analyse global changes in AS in multiple tissues, we identified the AS events and constructed a comprehensive catalogue of AS events within each tissue based on the genome-wide RNA-seq reads from ten tissues in cucumber. First, we found that 58% of the multi-exon genes underwent AS. We further obtained 565 genes with significantly more AS events compared with random genes. These genes were found significant enrichment in biological processes related to the regulation of actin filament length. Second, significantly different AS event profiles among ten tissues were found. The tissues with the same origin of development are more likely to have a relatively similar AS profile. Moreover, 7370 genes showed tissue-specific AS events and were highly enriched in biological processes related to the positive regulation of cellular component organization. Root-specificity AS genes were related to the cellular response to DNA damage stimulus. Third, the genes with different intron retention (IR) patterns among the ten tissues showed significant difference in GC percentages of the retained intron, and the number of exons and FPKM of the major transcripts. CONCLUSIONS: Our study provided a comprehensive view of AS in multiple tissues. We revealed novel insights into the patterns of AS in multiple tissues and the tissue-specific AS in cucumber.


Assuntos
Processamento Alternativo , Cucumis sativus/genética , Transcriptoma , Cucumis sativus/metabolismo , Perfilação da Expressão Gênica
20.
Small ; 14(6)2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29168915

RESUMO

Neutrophil dysfunction is strongly linked to type 2 diabetes mellitus (T2DM) pathophysiology, but the prognostic potential of neutrophil biomarkers remains largely unexplored due to arduous leukocyte isolation methods. Herein, a novel integrated microdevice is reported for single-step neutrophil sorting and phenotyping (chemotaxis and formation of neutrophil extracellular traps (NETosis)) using small blood volumes (fingerprick). Untouched neutrophils are purified on-chip from whole blood directly using biomimetic cell margination and affinity-based capture, and are exposed to preloaded chemoattractant or NETosis stimulant to initiate chemotaxis or NETosis, respectively. Device performance is first characterized using healthy and in vitro inflamed blood samples (tumor necrosis factor alpha, high glucose), followed by clinical risk stratification in a cohort of subjects with T2DM. Interestingly, "high-risk" T2DM patients characterized by severe chemotaxis impairment reveal significantly higher C-reactive protein levels and poor lipid metabolism characteristics as compared to "low-risk" subjects, and their neutrophil chemotaxis responses can be mitigated after in vitro metformin treatment. Overall, this unique and user-friendly microfluidics immune health profiling strategy can significantly aid the quantification of chemotaxis and NETosis in clinical settings, and be further translated into a tool for risk stratification and precision medicine methods in subjects with metabolic diseases such as T2DM.


Assuntos
Separação Celular/instrumentação , Diabetes Mellitus Tipo 2/sangue , Imunofenotipagem , Neutrófilos/citologia , Biomarcadores/sangue , Biomimética , Quimiotaxia de Leucócito , Diabetes Mellitus Tipo 2/tratamento farmacológico , Armadilhas Extracelulares , Humanos , Hipoglicemiantes/uso terapêutico , Dispositivos Lab-On-A-Chip , Metformina/uso terapêutico , Neutrófilos/imunologia , Estudo de Prova de Conceito
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