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1.
Sensors (Basel) ; 24(11)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38894177

RESUMO

Visual simultaneous localization and mapping (VSLAM) enhances the navigation of autonomous agents in unfamiliar environments by progressively constructing maps and estimating poses. However, conventional VSLAM pipelines often exhibited degraded performance in dynamic environments featuring mobile objects. Recent research in deep learning led to notable progress in semantic segmentation, which involves assigning semantic labels to image pixels. The integration of semantic segmentation into VSLAM can effectively differentiate between static and dynamic elements in intricate scenes. This paper provided a comprehensive comparative review on leveraging semantic segmentation to improve major components of VSLAM, including visual odometry, loop closure detection, and environmental mapping. Key principles and methods for both traditional VSLAM and deep semantic segmentation were introduced. This paper presented an overview and comparative analysis of the technical implementations of semantic integration across various modules of the VSLAM pipeline. Furthermore, it examined the features and potential use cases associated with the fusion of VSLAM and semantics. It was found that the existing VSLAM model continued to face challenges related to computational complexity. Promising future research directions were identified, including efficient model design, multimodal fusion, online adaptation, dynamic scene reconstruction, and end-to-end joint optimization. This review shed light on the emerging paradigm of semantic VSLAM and how deep learning-enabled semantic reasoning could unlock new capabilities for autonomous intelligent systems to operate reliably in the real world.

2.
Aging Male ; 26(1): 2261524, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37936343

RESUMO

Using Mendelian Randomization (MR) and large-scale Genome-Wide Association Study (GWAS) data, this study aimed to investigate the potential causative relationship between testosterone and sex hormone-binding globulin (SHBG) levels and the onset of several cancers, including pathway enrichment analyses of single nucleotide polymorphisms (SNPs) associated with cancer allowed for a comprehensive bioinformatics approach, which offered a deeper biological understanding of these relationships. The results indicated that increased testosterone levels in women were associated with a higher risk of breast and cervical cancers but a lower risk of ovarian cancer. Conversely, increased testosterone was linked to lower stomach cancer risk for men, whereas high SHBG levels were related to decreased risks of breast and prostate cancers. The corresponding genes of the identified SNPs, as revealed by pathway enrichment analysis, were involved in significant metabolic and proliferative pathways. These findings emphasize the need for further research into the biological mechanisms behind these associations, paving the way for potential targeted interventions in preventing and treating these cancers.


Assuntos
Neoplasias , Testosterona , Masculino , Humanos , Feminino , Globulina de Ligação a Hormônio Sexual/análise , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Neoplasias/genética
3.
Nano Lett ; 22(18): 7690-7698, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-36121208

RESUMO

The deluge of sensors and data generating devices has driven a paradigm shift in modern computing from arithmetic-logic centric to data-centric processing. Data-centric processing require innovations at the device level to enable novel compute-in-memory (CIM) operations. A key challenge in the construction of CIM architectures is the conflicting trade-off between the performance and their flexibility for various essential data operations. Here, we present a transistor-free CIM architecture that permits storage, search, and neural network operations on sub-50 nm thick Aluminum Scandium Nitride ferroelectric diodes (FeDs). Our circuit designs and devices can be directly integrated on top of Silicon microprocessors in a scalable process. By leveraging the field-programmability, nonvolatility, and nonlinearity of FeDs, search operations are demonstrated with a cell footprint <0.12 µm2 when projected onto 45 nm node technology. We further demonstrate neural network operations with 4-bit operation using FeDs. Our results highlight FeDs as candidates for efficient and multifunctional CIM platforms.


Assuntos
Escândio , Silício , Alumínio , Lógica , Redes Neurais de Computação
4.
Nano Lett ; 21(9): 3753-3761, 2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-33881884

RESUMO

Recent advances in oxide ferroelectric (FE) materials have rejuvenated the field of low-power, nonvolatile memories and made FE memories a commercial reality. Despite these advances, progress on commercial FE-RAM based on lead zirconium titanate has stalled due to process challenges. The recent discovery of ferroelectricity in scandium-doped aluminum nitride (AlScN) presents new opportunities for direct memory integration with logic transistors due to the low temperature of AlScN deposition (approximately 350 °C), making it compatible with back end of the line integration on silicon logic. Here, we present a FE-FET device composed of an FE-AlScN dielectric layer integrated with a two-dimensional MoS2 channel. Our devices show an ON/OFF ratio of ∼106, concurrent with a normalized memory window of 0.3 V/nm. The devices also demonstrate stable memory states up to 104 cycles and state retention up to 105 s. Our results suggest that the FE-AlScN/2D combination is ideal for embedded memory and memory-based computing architectures.

5.
Ophthalmic Res ; 64(5): 775-784, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32235125

RESUMO

BACKGROUND: Excessive scarring of filtering blebs is the main cause of surgical failure in glaucoma. Previous studies have highlighted the role of chloride channels (ClCs) in scar formation, whereas the role of ClCs in scarring of filtering blebs has not been studied. OBJECTIVES: The objective of this study was to investigate the effects of the chloride channel 2 (ClC-2) on scar formation of filtering blebs after glaucoma filtering surgery. METHODS: ClC-2 siRNA-transfected human conjunctival fibroblasts (HConFs) were cultured in type 1 collagen gels in the presence of transforming growth factor (TGF)-ß1. Collagen gel contraction was evaluated based on the gel area. 3D-cultured HConFs were treated with the ClC blocker NPPB in the presence of TGF-ß1, and cell proliferation collagen synthesis and contractility were measured. The expression levels of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) in HConFs were assessed by Western blotting and qPCR. RESULTS: TGF-ß1 induced cell proliferation, cell cycle progression, collagen synthesis, and collagen gel contraction in HConFs. TGF-ß1 increased MMP-2 and MMP-9 levels but inhibited the expression of TIMPs. NPPB and ClC-2 siRNA transfection inhibited TGF-ß2-induced cell proliferation, cell cycle progression, collagen synthesis, and collagen gel contraction, mediated by HConFs. TGF-ß2-induced increases in MMP-2 and MMP-9 were also inhibited by NPPB and ClC-2 siRNA transfection, but TIMP expression was increased by NPPB and ClC-2 siRNA transfection. CONCLUSIONS: These findings demonstrate that ClC-2 ClCs modulate TGF-ß1-induced cell proliferation, collagen synthesis, and collagen gel contraction of HConFs by attenuating MMP-2 and MMP-9 production and by stimulating TIMP1 production. NPPB may therefore prove to be of clinical value for the inhibition of scar formation of filtering blebs.


Assuntos
Glaucoma , Humanos , Proliferação de Células , Células Cultivadas , Cicatriz/genética , Canais de Cloro CLC-2/genética , Colágeno/metabolismo , Fibroblastos/metabolismo , Géis , Glaucoma/genética , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/genética , RNA Interferente Pequeno/genética , Fator de Crescimento Transformador beta1/farmacologia , Fator de Crescimento Transformador beta2/farmacologia
6.
BMC Biol ; 18(1): 189, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-33272269

RESUMO

BACKGROUND: The adenosine-to-inosine (A-to-I) editing in anticodons of tRNAs is critical for wobble base-pairing during translation. This modification is produced via deamination on A34 and catalyzed by the adenosine deaminase acting on tRNA (ADAT) enzyme. Eukaryotic ADATs are heterodimers composed of the catalytic subunit ADAT2 and the structural subunit ADAT3, but their molecular assemblies and catalytic mechanisms are largely unclear. RESULTS: Here, we report a 2.8-Å crystal structure of Saccharomyces cerevisiae ADAT2/3 (ScADAT2/3), revealing its heterodimeric assembly and substrate recognition mechanism. While each subunit clearly contains a domain resembling their prokaryotic homolog TadA, suggesting an evolutionary gene duplication event, they also display accessory domains for additional structural or functional purposes. The N-lobe of ScADAT3 exhibits a positively charged region with a potential role in the recognition and binding of tRNA, supported by our biochemical analysis. Interestingly, ScADAT3 employs its C-terminus to block tRNA's entry into its pseudo-active site and thus inactivates itself for deamination despite the preservation of a zinc-binding site, a mechanism possibly shared only among yeasts. CONCLUSIONS: Combining the structural with biochemical, bioinformatic, and in vivo functional studies, we propose a stepwise model for the pathway of deamination by ADAT2/3. Our work provides insight into the molecular mechanism of the A-to-I editing by the eukaryotic ADAT heterodimer, especially the role of ADAT3 in catalysis.


Assuntos
Anticódon/genética , Saccharomyces cerevisiae/genética , Filogenia , Multimerização Proteica , Estrutura Secundária de Proteína , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/enzimologia
7.
Nano Lett ; 20(4): 2907-2915, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32196351

RESUMO

van der Waals (vdW) semiconductors are attractive for highly scaled devices and heterogeneous integration as they can be isolated into self-passivated, two-dimensional (2D) layers that enable superior electrostatic control. These attributes have led to numerous demonstrations of field-effect devices ranging from transistors to triodes. By exploiting the controlled, substitutional doping schemes in covalently bonded, three-dimensional (3D) semiconductors and the passivated surfaces of 2D semiconductors, one can construct devices that can exceed performance metrics of "all-2D" vdW heterojunctions. Here, we demonstrate 2D/3D semiconductor heterojunctions using MoS2 as the prototypical 2D semiconductor laid upon Si and GaN as the 3D semiconductor layers. By tuning the Fermi levels in MoS2, we demonstrate devices that concurrently exhibit over 7 orders of magnitude modulation in rectification ratios and conductance. Our results further suggest that the interface quality does not necessarily affect Fermi level tuning at the junction, opening up possibilities for novel 2D/3D heterojunction device architectures.

8.
Molecules ; 26(9)2021 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-34066875

RESUMO

The main core of wound treatment is cell growth and anti-infection. To accelerate the proliferation of fibroblasts in the wound and prevent wound infections, various strategies have been tried. It remains a challenge to obtain good cell proliferation and antibacterial effects. Here, human hair kerateine (HHK)/poly(ethylene oxide) (PEO)/poly(vinyl alcohol) (PVA) nanofibers were prepared using cysteine-rich HHK, and then, silver nanoparticles (AgNPs) were in situ anchored in the sulfur-containing amino acid residues of HHK. After the ultrasonic degradation test, HHK/PEO/PVA nanofibrous mats treated with 0.005-M silver nitrate were selected due to their relatively complete structures. It was observed by TEM-EDS that the sulfur-containing amino acids in HHK were the main anchor points of AgNPs. The results of FTIR, XRD and the thermal analysis suggested that the hydrogen bonds between PEO and PVA were broken by HHK and, further, by AgNPs. AgNPs could act as a catalyst to promote the thermal degradation reaction of PVA, PEO and HHK, which was beneficial for silver recycling and medical waste treatment. The antibacterial properties of AgNP-HHK/PEO/PVA nanofibers were examined by the disk diffusion method, and it was observed that they had potential antibacterial capability against Gram-positive bacteria, Gram-negative bacteria and fungi. In addition, HHK in the nanofibrous mats significantly improved the cell proliferation of NIH3T3 cells. These results illustrated that the AgNP-HHK/PEO/PVA nanofibrous mats exhibited excellent antibacterial activity and the ability to promote the proliferation of fibroblasts, reaching our target applications.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Proliferação de Células/efeitos dos fármacos , Queratinas Específicas do Cabelo/química , Nanopartículas Metálicas/química , Nanofibras/química , Polietilenoglicóis/química , Álcool de Polivinil/química , Prata/química , Animais , Candida albicans/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Cabelo/química , Humanos , Ligação de Hidrogênio , Camundongos , Testes de Sensibilidade Microbiana , Células NIH 3T3 , Nitrato de Prata/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Cicatrização/efeitos dos fármacos
9.
J Sep Sci ; 43(9-10): 1847-1853, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32057182

RESUMO

Diffusion of the analytes across the diffusion boundary layers and subsequently through the fiber coatings determines the extraction kinetics of solid-phase microextraction in aqueous matrices. Besides, the matrix effects can distort the behaviors of the analytes transferring across the diffusion boundary layers. However, these processes were always studied via certain simplification, which often left the mass transfer through the fiber coatings unconsidered and the matrix effects partially investigated. Herein, a comprehensive study on the mass transfer processes in direct immersion solid-phase microextraction was presented. Under different agitation speeds, it was determined that the mass transfer coefficients across the diffusion boundary layers were three to six orders larger than those through the fiber coatings. However, the mass transfer across the diffusion boundary layers was generally the major rate-limiting step. In addition, the shuttle effect and the barrier effect, which were responsible for accelerating and retarding the extraction kinetics, respectively, were found to be the dominant matrix effect alternately under different agitation speeds. This study comprehensively illustrated the major rate-limiting step and the dominant matrix effects through recording the mass transfer coefficients.

10.
Mediators Inflamm ; 2020: 8292173, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33456372

RESUMO

Vestigial-like 4 (VGLL4) has been found to have multiple functions in tumor development; however, its role in cardiovascular disease is unknown. The aim of this study was to investigate the effect of VGLL4 on the dysfunction and inflammatory response of Ox-LDL-induced human umbilical vein endothelial cells (HUVECs) and its mechanism, so as to provide a new theoretical basis for the diagnosis and treatment of atherosclerosis. In the present study, the protective activity of VGLL4 inhibiting Ox-LDL-induced apoptosis, oxidative stress, inflammation, and injury as well as its molecular mechanisms was examined using human umbilical vein endothelial cells (HUVECs). The results showed that the expression of VGLL4 was decreased with the increase of Ox-LDL concentration in HUVECs. In addition, the functional study found that VGLL4 overexpression alleviated Ox-LDL-induced oxidative stress, inflammation, and dysfunction and inhibited apoptosis. Further research found that VGLL4 regulated Hippo-YAP/TEAD1 signaling pathway, and the Hippo-YAP/TEAD1 signaling pathway was involved in the protective mechanism of VGLL4 on HUVECs. In conclusion, it suggests that VGLL4 protects against oxidized-LDL-induced endothelial cell dysfunction by activating the Hippo-YAP/TEAD1 signaling pathway.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ligação a DNA/metabolismo , Células Endoteliais/metabolismo , Lipoproteínas LDL/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Fatores de Transcrição/metabolismo , Trifosfato de Adenosina/metabolismo , Apoptose , Aterosclerose , Sobrevivência Celular/efeitos dos fármacos , Via de Sinalização Hippo , Células Endoteliais da Veia Umbilical Humana , Humanos , Inflamação , Estresse Oxidativo , Substâncias Protetoras/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Fatores de Transcrição de Domínio TEA , Proteínas de Sinalização YAP
11.
Sensors (Basel) ; 20(17)2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32887432

RESUMO

The ore fragment size on the conveyor belt of concentrators is not only the main index to verify the crushing process, but also affects the production efficiency, operation cost and even production safety of the mine. In order to get the size of ore fragments on the conveyor belt, the image segmentation method is a convenient and fast choice. However, due to the influence of dust, light and uneven color and texture, the traditional ore image segmentation methods are prone to oversegmentation and undersegmentation. In order to solve these problems, this paper proposes an ore image segmentation model called RDU-Net (R: residual connection; DU: DUNet), which combines the residual structure of convolutional neural network with DUNet model, greatly improving the accuracy of image segmentation. RDU-Net can adaptively adjust the receptive field according to the size and shape of different ore fragments, capture the ore edge of different shape and size, and realize the accurate segmentation of ore image. The experimental results show that compared with other U-Net and DUNet, the RDU-Net has significantly improved segmentation accuracy, and has better generalization ability, which can fully meet the requirements of ore fragment size detection in the concentrator.

12.
PLoS Biol ; 14(3): e1002423, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27014876

RESUMO

Alarm communication is a key adaptation that helps social groups resist predation and rally defenses. In Asia, the world's largest hornet, Vespa mandarinia, and the smaller hornet, Vespa velutina, prey upon foragers and nests of the Asian honey bee, Apis cerana. We attacked foragers and colony nest entrances with these predators and provide the first evidence, in social insects, of an alarm signal that encodes graded danger and attack context. We show that, like Apis mellifera, A. cerana possesses a vibrational "stop signal," which can be triggered by predator attacks upon foragers and inhibits waggle dancing. Large hornet attacks were more dangerous and resulted in higher bee mortality. Per attack at the colony level, large hornets elicited more stop signals than small hornets. Unexpectedly, stop signals elicited by large hornets (SS large hornet) had a significantly higher vibrational fundamental frequency than those elicited by small hornets (SS small hornet) and were more effective at inhibiting waggle dancing. Stop signals resulting from attacks upon the nest entrance (SS nest) were produced by foragers and guards and were significantly longer in pulse duration than stop signals elicited by attacks upon foragers (SS forager). Unlike SS forager, SS nest were targeted at dancing and non-dancing foragers and had the common effect, tuned to hornet threat level, of inhibiting bee departures from the safe interior of the nest. Meanwhile, nest defenders were triggered by the bee alarm pheromone and live hornet presence to heat-ball the hornet. In A. cerana, sophisticated recruitment communication that encodes food location, the waggle dance, is therefore matched with an inhibitory/alarm signal that encodes information about the context of danger and its threat level.


Assuntos
Comunicação Animal , Abelhas , Animais , Feromônios , Comportamento Predatório , Vibração , Vespas
13.
Med Sci Monit ; 25: 8120-8130, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31662580

RESUMO

BACKGROUND Our previous study found a novel fluid combination with better resuscitation effects under hypotensive condition at the early stage of uncontrolled hemorrhagic shock (UHS). However, the optimal recovery concentration of hypertonic saline in this fluid combination remains unknown. This experiment aimed to explore the optimal concentration. MATERIAL AND METHODS New Zealand white rabbits (n=40) were randomly divided into 5 groups, including a sham-operated group (SO), a shock non-treated group (SNT), a normal saline group (NS), and hypertonic saline groups (4.5% and 7.5%). We established an UHS model and administered various fluid combinations (dose-related sodium chloride solution+crystal-colloidal solution) to the groups followed by monitoring indexes of hemodynamic and renal function, measuring infusion volume and blood loss, and analyzing pathological morphology by hematoxylin and eosin staining. RESULTS The hypertonic saline groups showed more stable hemodynamic indexes, reduced blood loss, fewer required infusions, and milder decreases in renal function than those of control groups (SNT and NS groups), and exhibited fewer pathological changes in the heart, lung, kidney, and liver. All indexes in the 4.5% and 7.5% groups were better than those of the NS group, and the hemodynamic indexes in the 7.5% group were more stable than those of the 4.5% group (P<0.05), with reduced blood loss and infusion volume and a milder decrease in renal function. CONCLUSIONS The novel fluid combination with 7.5% hypertonic saline group had a better recovery effect at the early stage of UHS before hemostasis compared to that of the 4.5% hypertonic saline group. This result may provide guidance for clinical fluid resuscitation.


Assuntos
Solução Salina Hipertônica/uso terapêutico , Choque Hemorrágico/tratamento farmacológico , Cloreto de Sódio/uso terapêutico , Animais , Pressão Sanguínea , Hidratação/métodos , Hemodinâmica , Hipotensão , Masculino , Modelos Animais , Coelhos , Ressuscitação
14.
Anal Chem ; 90(3): 1572-1577, 2018 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-29285930

RESUMO

Solid-phase microextraction (SPME) coupled with liquid chromatograph (LC) is widely used to detect polar and ionic organic compounds, including various pharmaceuticals and endogenous bioactive compounds. In this study, a small-sized insert tube for use in the commercial autosampler vial was designed for eluting the extracted analytes from SPME fibers for LC analysis. By using this custom-made insert tube as an alternative to the commercial insert tube, the volume of the elution solvent was reduced by four-fifths. Even though smaller fractions of the analytes were eluted from the fiber coatings, the analyte concentrations in the elution solutions were substantially increased by using the custom-made insert tube. Therefore, larger amounts of the analytes could be injected to LC and higher signal-to-noise ratios could be achieved, even at smaller injection volumes. Since the elution in the custom-made insert tube was nonexhaustive, four strategies were developed to figure out the extracted amounts in the fiber coatings. In combination with the sampling-rate calibration method, these strategies were successfully used to determine the concentrations of fluoxetine in living tilapias. This study provides a simple but effect way for improving the analytical sensitivity when coupling SPME with LC.

15.
Anal Chem ; 90(14): 8304-8308, 2018 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-29963850

RESUMO

Miniaturized sample pretreatment platforms have simplified analytical tasks in diverse disciplines. Herein, a novel pipet microextraction (PME) device is reported by making use of the photothermal property of a light-heatable sorbent (LHS) for the first time. Efficient and staining-free heating treatment of small volumes of liquids confined in the PME device is now enabled through light illumination. The light-induced heating treatment is capable of dramatically accelerating solvent elution rates, effectively unlocking bound toxin from its antibody, and rapidly quenching enzymatic activities, thus, provides PME with higher efficiencies and enables its new applications in antibody-intermediated sampling of targeted toxin from stained food surfaces and powders, as well as in accurate revelation of enzymatic reaction kinetics. This study offers a new perspective of designing efficient and versatile microextraction platforms and demonstrates their potential applications in different fields including public security, new drug development, and environmental protection.

16.
Int J Obes (Lond) ; 42(12): 1999-2011, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29568102

RESUMO

BACKGROUND: Visceral fat accumulation increases the risk of developing type 2 diabetes and metabolic syndrome, and is associated with excessive glucocorticoids (GCs). Fat depot-specific GC action is tightly controlled by 11ß-hydroxysteroid dehydrogenase (11ß-HSD1) coupled with the enzyme hexose-6-phosphate dehydrogenase (H6PDH). Mice with inactivation or activation of H6PDH genes show altered adipose 11ß-HSD1 activity and lipid storage. We hypothesized that adipose tissue H6PDH activation is a leading cause for the visceral obesity and insulin resistance. Here, we explored the role and possible mechanism of enhancing adipose H6PDH in the development of visceral adiposity in vivo. METHODS: We investigated the potential contribution of adipose H6PDH activation to the accumulation of visceral fat by characterization of visceral fat obese gene expression profiles, fat distribution, adipocyte metabolic molecules, and abdominal fat-specific GC signaling mechanisms underlying the diet-induced visceral obesity and insulin resistance in H6PDH transgenic mice fed a standard of high-fat diet (HFD). RESULTS: Transgenic H6PDH mice display increased abdominal fat accumulation, which is paralleled by elevated lipid synthesis associated with induction of lipogenic transcriptor C/EBPα and PPARγ mRNA levels within adipose tissue. Transgenic H6PDH mice fed a high-fat diet (HFD) gained more abdominal visceral fat mass coupled with activation of GSK3ß and induction of XBP1/IRE1α, but reduced pThr308 Akt/PKB content and browning gene CD137 and GLUT4 mRNA levels within the visceral adipose tissue than WT controls. HFD-fed H6PDH transgenic mice also had impaired insulin sensitivity and exhibited elevated levels of intra-adipose GCs with induction of adipose 11ß-HSD1. CONCLUSION: These data provide the first in vivo mechanistic evidence for the adverse metabolic effects of adipose H6PDH activation on visceral fat distribution, fat metabolism, and adipocyte function through enhancing 11ß-HSD1-driven intra-adipose GC action.


Assuntos
Tecido Adiposo/enzimologia , Desidrogenases de Carboidrato/metabolismo , Obesidade Abdominal/metabolismo , Adipócitos/metabolismo , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Animais , Desidrogenases de Carboidrato/análise , Desidrogenases de Carboidrato/genética , Dieta Hiperlipídica , Masculino , Camundongos , Camundongos Transgênicos , Obesidade Abdominal/genética , Transcriptoma/genética
17.
Proc Biol Sci ; 284(1851)2017 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-28356452

RESUMO

In the social insects, ovary state (the presence or absence of mature oocytes) and ovary size (the number of ovarioles) are often used as proxies for the reproductive capacity of an individual worker. Ovary size is assumed to be fixed post-eclosion whereas ovary state is demonstrably plastic post-eclosion. Here, we show that in fact ovary size declines as honeybee workers age. This finding is robust across two honeybee species: Apis mellifera and A. cerana The ovariole loss is likely to be due to the regression of particular ovarioles via programmed cell death. We also provide further support for the observation that honeybee workers with activated ovaries (mature oocytes present) most commonly have five ovarioles rather than a greater or smaller number. This result suggests that workers with more than five ovarioles are unable to physiologically support more than five activated ovarioles and that workers with fewer than five ovarioles are below a threshold necessary for ovary activation. As a worker's ovariole number declines with age, studies on worker ovariole number need to take this plasticity into account.


Assuntos
Abelhas/fisiologia , Infertilidade , Ovário/fisiologia , Animais , Apoptose , Feminino , Reprodução
18.
Plant Cell Rep ; 35(2): 385-95, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26581952

RESUMO

KEY MESSAGE: SpAQP1 was strongly induced by salt in an ABA-independent way, promoted seed germination and root growth in transgenic tobaccos and increased salt tolerance by increasing the activities of antioxidative enzymes. Aquaporin (AQP) plays crucial roles in the responses of plant to abiotic stresses such as drought, salt and cold. Compared to glycophytes, halophytes often have excellent salt and drought tolerances. To uncover the molecular mechanism of halophyte Sesuvium portulacastrum tolerance to salt, in this study, an AQP gene, SpAQP1, from S. portulacastrum was isolated and characterized. The amino acid sequence of SpAQP1 shared high homology with that of plant plasma membrane intrinsic proteins (PIPs) and contained the distinct molecular features of PIPs. In the phylogenic tree, SpAQP1 was evidently classified as the PIP2 subfamily. SpAQP1 is expressed in roots, stems and leaves, and was significantly induced by NaCl treatment and inhibited by abscisic acid (ABA) treatment. When heterologously expressed in yeast and tobacco, SpAQP1 enhanced the salt tolerance of yeast strains and tobacco plants and promoted seed germination and root growth under salt stress in transgenic plants. The activity of antioxidative enzymes including superoxide dismutase, peroxidase and catalase was increased in transgenic plants overexpressing SpAQP1. Taken together, our studies suggested that SpAQP1 functioned in the responses of S. portulacastrum to salt stress and could increase salt tolerance by enhancing the antioxidative activity of plants.


Assuntos
Aizoaceae/genética , Aquaporinas/genética , Aquaporinas/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Tolerância ao Sal/genética , Plantas Tolerantes a Sal/genética , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas/genética
19.
J Anim Ecol ; 84(2): 509-17, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25251672

RESUMO

Most models of animal choice behaviour assume that desirable but unavailable options, such as a high quality, but inhabited nest sites, do not influence an individual's preferences for the remaining options. However, experiments suggest that in mammals, the mere presence of such 'phantom' alternatives can alter, and even reverse, an individual's preferences for other items in a choice set. Phantom alternatives may be widespread in nature, as they occur whenever a resource is visible, but unavailable at the time of choice. They are particularly relevant for nectar-foraging animals, where previously rewarding flowers may sometimes be empty. Here, we investigate the effect of phantom alternatives on feeder preferences in the eastern honeybee, Apis cerana. First, we tested the effects of unattractive and attractive phantom alternatives by presenting individual bees with either a binary choice set containing two feeders that differed strongly in two qualities, but were equally preferred overall ('option 1' and 'option 2'), or a ternary choice set containing option 1, option 2 and one of two phantom types (unattractive and attractive). Secondly, we determined whether phantoms increase (similarity effect) or decrease (dissimilarity effect) preference for phantom-similar choices. In binary trials, bees had no significant preference for option 1 or option 2. However, after encountering an attractive phantom alternative, individual bees preferred option 2. The unattractive phantom did not influence bee preferences. Phantoms consistently changed individual bee preferences in favour of the phantom-similar choice. This means that the presence of an attractive food source, even if it is unavailable, can influence preference relationships between remaining items in the choice set. Our findings highlight the importance of considering the potential for phantom effects when studying the foraging behaviour of animals. Our results are particularly relevant for nectarivores, where empty but previously rewarding flowers are a common occurrence. Since an increase in pollinator visits can result in higher seed set, our results open up the possibility that by shifting pollinator preferences, empty flowers could have otherwise-unpredicted influences on community composition, plant-pollinator interactions and pollinator behaviour.


Assuntos
Abelhas/fisiologia , Animais , Comportamento Apetitivo , Preferências Alimentares
20.
Psychooncology ; 23(7): 721-30, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24590866

RESUMO

OBJECTIVE: With increasing expectations of a 5-year survival rate among cancer patients, there is growing interest in patient-reported outcome (PRO) measures, particularly measures of health-related quality of life (HRQOL) in cancer practice. The purpose of this review was to explore the existing interventions for patients coping with cancer in terms of intervention type, PRO measurements and outcomes; and to identify directions for future research. METHODS: Systematic review of randomised clinical trials. A systematic search of four databases was conducted to identify articles published in English or Chinese from January 2000 to July 2013. Studies were located using an electronic search, a manual search and an author search. RESULTS: A total of 34 articles corresponding to 33 original studies were identified and included in this review. These interventions were classified under four broad categories according to their approaches: psycho-education (15), case management (13), exercise (4) and feedback of PRO (1). The PRO measures covered different types of PRO measures, including HRQOL, functional status, symptom status, overall well-being and satisfaction with care. Positive outcomes of more than 70% (24) out of these interventions were reported. CONCLUSIONS: These findings highlight the significant outcomes of cancer patient interventions that applied PRO measures to evaluate their outcomes. A theory-driven and careful design of the programme should be considered in the whole process of developing, delivering and assessing the programmes. Collaboration among patients, clinicians, researchers and policy makers is crucial to ensure the development of effective and accessible interventions targeting improving cancer survivors' HRQOL.


Assuntos
Neoplasias/psicologia , Avaliação de Resultados da Assistência ao Paciente , Qualidade de Vida/psicologia , Sobreviventes/psicologia , Humanos , Neoplasias/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto
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