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1.
Proc Natl Acad Sci U S A ; 119(43): e2211688119, 2022 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-36252036

RESUMO

The nucleus accumbens (NAc) is a canonical reward center that regulates feeding and drinking but it is not known whether these behaviors are mediated by same or different neurons. We employed two-photon calcium imaging in awake, behaving mice and found that during the appetitive phase, both hunger and thirst are sensed by a nearly identical population of individual D1 and D2 neurons in the NAc that respond monophasically to food cues in fasted animals and water cues in dehydrated animals. During the consummatory phase, we identified three distinct neuronal clusters that are temporally correlated with action initiation, consumption, and cessation shared by feeding and drinking. These dynamic clusters also show a nearly complete overlap of individual D1 neurons and extensive overlap among D2 neurons. Modulating D1 and D2 neural activities revealed analogous effects on feeding versus drinking behaviors. In aggregate, these data show that a highly overlapping set of D1 and D2 neurons in NAc detect food and water reward and elicit concordant responses to hunger and thirst. These studies establish a general role of this mesolimbic pathway in mediating instinctive behaviors by controlling motivation-associated variables rather than conferring behavioral specificity.


Assuntos
Fome , Sede , Animais , Cálcio/metabolismo , Camundongos , Núcleo Accumbens/fisiologia , Recompensa , Água/metabolismo
2.
Nano Lett ; 24(8): 2619-2628, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38350110

RESUMO

Post-extraction alveolar bone atrophy greatly hinders the subsequent orthodontic tooth movement (OTM) or implant placement. In this study, we synthesized biodegradable bifunctional bioactive calcium phosphorus nanoflowers (NFs) loaded with abaloparatide (ABL), namely ABL@NFs, to achieve spatiotemporal management for alveolar bone regeneration. The NFs exhibited a porous hierarchical structure, high drug encapsulation efficacy, and desirable biocompatibility. ABL was initially released to recruit stem cells, followed by sustained release of Ca2+ and PO43- for in situ interface mineralization, establishing an osteogenic "biomineralized environment". ABL@NFs successfully restored morphologically and functionally active alveolar bone without affecting OTM. In conclusion, the ABL@NFs demonstrated promising outcomes for bone regeneration under orthodontic condition, which might provide a desirable reference of man-made "bone powder" in the hard tissue regeneration field.


Assuntos
Regeneração Óssea , Osteogênese , Proteína Relacionada ao Hormônio Paratireóideo , Humanos , Osso e Ossos , Porosidade
3.
Int J Mol Sci ; 25(8)2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38674154

RESUMO

As global climate change continues, drought episodes have become increasingly frequent. Studying plant stress tolerance is urgently needed to ensure food security. The common ice plant is one of the model halophyte plants for plant stress biology research. This study aimed to investigate the functions of a newly discovered transcription factor, Homeobox 7 (HB7), from the ice plant in response to drought stress. An efficient Agrobacterium-mediated transformation method was established in the ice plant, where ectopic McHB7 expression may be sustained for four weeks. The McHB7 overexpression (OE) plants displayed drought tolerance, and the activities of redox enzymes and chlorophyll content in the OE plants were higher than the wild type. Quantitative proteomics revealed 1910 and 495 proteins significantly changed in the OE leaves compared to the wild type under the control and drought conditions, respectively. Most increased proteins were involved in the tricarboxylic acid cycle, photosynthesis, glycolysis, pyruvate metabolism, and oxidative phosphorylation pathways. Some were found to participate in abscisic acid signaling or response. Furthermore, the abscisic acid levels increased in the OE compared with the wild type. McHB7 was revealed to bind to the promoter motifs of Early Responsive to Dehydration genes and abscisic acid-responsive genes, and protein-protein interaction analysis revealed candidate proteins responsive to stresses and hormones (e.g., abscisic acid). To conclude, McHB7 may contribute to enhance plant drought tolerance through abscisic acid signaling.


Assuntos
Ácido Abscísico , Secas , Regulação da Expressão Gênica de Plantas , Transdução de Sinais , Estresse Fisiológico , Fatores de Transcrição , Ácido Abscísico/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Proteômica/métodos , Proteínas de Homeodomínio/metabolismo , Proteínas de Homeodomínio/genética , Resistência à Seca
4.
Mol Med ; 29(1): 161, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38017373

RESUMO

BACKGROUND: Liver aging, marked by cellular senescence and low-grade inflammation, heightens susceptibility to chronic liver disease and worsens its prognosis. Insulin-like growth factor 2 (IGF2) has been implicated in numerous aging-related diseases. Nevertheless, its role and underlying molecular mechanisms in liver aging remain largely unexplored. METHODS: The expression of IGF2 was examined in the liver of young (2-4 months), middle-aged (9-12 months), and old (24-26 months) C57BL/6 mice. In vivo, we used transgenic IGF2f/f; Alb-Cre mice and D-galactose-induced aging model to explore the role of IGF2 in liver aging. In vitro, we used specific short hairpin RNA against IGF2 to knock down IGF2 in AML12 cells. D-galactose and hydrogen peroxide treatment were used to induce AML12 cell senescence. RESULTS: We observed a significant reduction of IGF2 levels in the livers of aged mice. Subsequently, we demonstrated that IGF2 deficiency promoted senescence phenotypes and senescence-associated secretory phenotypes (SASPs), both in vitro and in vivo aging models. Moreover, IGF2 deficiency impaired mitochondrial function, reducing mitochondrial respiratory capacity, mitochondrial membrane potential, and nicotinamide adenine dinucleotide (NAD)+/NADH ratio, increasing intracellular and mitochondrial reactive oxygen species levels, and disrupting mitochondrial membrane structure. Additionally, IGF2 deficiency markedly upregulated CCAAT/enhancer-binding protein beta (CEBPB). Notably, inhibiting CEBPB reversed the senescence phenotypes and reduced SASPs induced by IGF2 deficiency. CONCLUSIONS: In summary, our findings strongly suggest that IGF2 deficiency promotes liver aging through mitochondrial dysfunction and upregulated CEBPB signaling. These results provide compelling evidence for considering IGF2 as a potential target for interventions aimed at slowing down the process of liver aging.


Assuntos
Envelhecimento , Galactose , Animais , Camundongos , Envelhecimento/metabolismo , Galactose/metabolismo , Galactose/farmacologia , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo
5.
Int J Mol Sci ; 24(17)2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37685878

RESUMO

Global climate change and population growth are persistently posing threats to natural resources (e.g., freshwater) and agricultural production. Crassulacean acid metabolism (CAM) evolved from C3 photosynthesis as an adaptive form of photosynthesis in hot and arid regions. It features the nocturnal opening of stomata for CO2 assimilation, diurnal closure of stomata for water conservation, and high water-use efficiency. To cope with global climate challenges, the CAM mechanism has attracted renewed attention. Facultative CAM is a specialized form of CAM that normally employs C3 or C4 photosynthesis but can shift to CAM under stress conditions. It not only serves as a model for studying the molecular mechanisms underlying the CAM evolution, but also provides a plausible solution for creating stress-resilient crops with facultative CAM traits. This review mainly discusses the recent research effort in defining the C3 to CAM transition of facultative CAM plants, and highlights challenges and future directions in this important research area with great application potential.


Assuntos
Metabolismo Ácido das Crassuláceas , Fotossíntese , Agricultura , Mudança Climática , Produtos Agrícolas
6.
Opt Express ; 30(25): 45488-45498, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36522953

RESUMO

Pancharatnam-Berry (PB) metasurfaces have demonstrated mighty capability to manipulate electromagnetic (EM) waves, and exhibited potential applications for devices with broadband and efficient functionality. However, it remains a challenge to simultaneously achieve broadband and efficient wavefront manipulation for terahertz (THz) components with simple profiles. Herein, we introduce a simple ultra-thin PB metasurface with superior properties in the THz region. The structure is composed of a simple metallic C-Shaped Split Ring Resonator (CSRR) patterned on a flexible polyimide support layer. It is verified that the circular transmission efficiency is close to the theoretical limit of the single-layer metasurface in the range of 0.6 - 1.2 THz. Furthermore, we design metasurfaces based on the PB meta-atoms with spatially rotated orientation to achieve beam steering and superposition of vortex waves. The results are basically in line with expectations, validating the good performances of our proposal. This simple and easily deployable metasurface will give rise to more possibilities for the design of THz functional devices.

7.
J Nanobiotechnology ; 20(1): 238, 2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35590414

RESUMO

Tumor killing and wound healing are two complementary and influential processes during the treatment of melanoma. Herein, a two-layered microneedle platform was developed with bifunctional effect of chemo-photothermal synergistic melanoma therapy and skin regeneration. The bifunctional platform composed of embeddable curcumin nanodrugs/new Indocyanine Green/hyaluronic acid (Cur NDs/IR820/HA) microneedles and sodium alginate/gelatin/hyaluronic acid (SA/Ge/HA) supporting backing layer was prepared through a two-step casting process. With uniform incorporation of curcumin nanodrugs and IR820, the microneedles exhibited excellent photothermal performance under external near-infrared (NIR) light stimulation and tumor co-therapy ability. Once the embeddable microneedles were inserted into skin, they would rapidly dissolve and activate drug release successfully for tumor treatment. Moreover, the SA/Ge/HA supporting backing layer was left behind to cover the wound and promote the proliferation of endothelial and fibroblasts cells for enhanced skin regeneration. The two-layered microneedles platform can simultaneously eliminate the tumor and accelerate wounding healing, which may be potentially employed as a competitive strategy for the treatment of melanoma.


Assuntos
Curcumina , Melanoma , Nanopartículas , Linhagem Celular Tumoral , Curcumina/farmacologia , Liberação Controlada de Fármacos , Humanos , Ácido Hialurônico , Melanoma/tratamento farmacológico , Fototerapia , Terapia Fototérmica , Cicatrização
8.
Int J Mol Sci ; 23(14)2022 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-35887227

RESUMO

Mesembryanthemum crystallinum (common ice plant) is one of the facultative halophyte plants, and it serves as a model for investigating the molecular mechanisms underlying its salt stress response and tolerance. Here we cloned one of the homeobox transcription factor (TF) genes, McHB7, from the ice plant, which has 60% similarity with the Arabidopsis AtHB7. Overexpression of the McHB7 in Arabidopsis (OE) showed that the plants had significantly elevated relative water content (RWC), chlorophyll content, superoxide dismutase (SOD), and peroxidase (POD) activities after salt stress treatment. Our proteomic analysis identified 145 proteins to be significantly changed in abundance, and 66 were exclusively increased in the OE plants compared to the wild type (WT). After salt treatment, 979 and 959 metabolites were significantly increased and decreased, respectively, in the OE plants compared to the WT. The results demonstrate that the McHB7 can improve photosynthesis, increase the leaf chlorophyll content, and affect the TCA cycle by regulating metabolites (e.g., pyruvate) and proteins (e.g., citrate synthase). Moreover, McHB7 modulates the expression of stress-related proteins (e.g., superoxide dismutase, dehydroascorbate reductase, and pyrroline-5-carboxylate synthase B) to scavenge reactive oxygen species and enhance plant salt tolerance.


Assuntos
Arabidopsis , Mesembryanthemum , Arabidopsis/genética , Arabidopsis/metabolismo , Clorofila/metabolismo , Regulação da Expressão Gênica de Plantas , Mesembryanthemum/genética , Mesembryanthemum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteômica , Tolerância ao Sal/genética , Superóxido Dismutase/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
9.
Clin Sci (Lond) ; 135(7): 979-990, 2021 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-33825857

RESUMO

Exercise training improves muscle fitness in many aspects, including induction of mitochondrial biogenesis and maintenance of mitochondrial dynamics. The insulin-like growth factors were recently proposed as key regulators of myogenic factors to regulate muscle development. The present study aimed to investigate the physical exercise impact on insulin-like growth factor 2 (IGF2) and analyzed its functions on skeletal muscle cells in vitro. Using online databases, we stated that IGF2 was relatively highly expressed in skeletal muscle cells and increased after exercise training. Then, IGF2 deficiency in myotubes from C2C12 and primary skeletal muscle cells (PMSCs) led to impaired mitochondrial function, reduced mitochondria-related protein content, and decreased mitochondrial biogenesis. Furthermore, we explored the possible regulatory pathway and found that mitochondrial regulation in skeletal muscle cells might occur through IGF2-Sirtuin 1 (SIRT1)-peroxisome proliferator-activated receptor-γ co-activator-1α (PGC1α) signaling pathway. Therefore, the present study first demonstrated the relationship between IGF2 and mitochondria in skeletal muscle.


Assuntos
Mitocôndrias Musculares/metabolismo , Músculo Esquelético/metabolismo , Somatomedinas/deficiência , Animais , Animais Recém-Nascidos , Linhagem Celular , Células Cultivadas , Camundongos , Camundongos Endogâmicos C57BL , Fibras Musculares Esqueléticas , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Transdução de Sinais , Sirtuína 1/metabolismo
10.
Int J Legal Med ; 135(3): 709-718, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32851473

RESUMO

The MiSeq® FGX Forensic system and the HID-Ion AmpliSeq Panel were previously developed for massively parallel sequencing (MPS) for forensic casework. Among the three major sequencing platforms, BGISEQ-500TM, which is based on multiple PCRs, is still lacking in forensics. Here, a novel forensic panel was constructed to detect 186 single-nucleotide polymorphisms (SNPs) and 123 short tandem repeats (STRs) with MPS technology on the BGISEQ-500™ platform. First, the library preparation, sequencing process, and data analysis were performed, focusing on the average depth of coverage and heterozygote balance. We calculated the allelic frequencies and forensic parameters of STR and SNP loci in 73 unrelated Chinese Han individuals. In addition, performance was evaluated with accuracy, uniformity, sensitivity, PCR inhibitor, repeatability and reproducibility, mixtures, degraded samples, case-type samples, and pedigree analyses. The results showed that 100% accurate and concordant genotypes can be obtained, and the loci with an abundance in the interquartile range accounted for 92.90% of the total, suggesting reliable uniformity in this panel. We obtained a locus detection rate that was higher than 98.78% from 78 pg of input DNA, and the optimal amount was 1.25-10 ng. The maximum concentrations of hematin and humic acid were 200 and 100 µM, respectively (the ratios of detected loci were 96.52% and 92.41%), in this panel. As a mixture, compared with those of SNPs, minor-contributor alleles of STRs could be detected at higher levels. For the degraded sample, the ratio of detected loci was 98.41%, and most profiles from case-type samples were not significantly different in abundance in our studies. As a whole, this panel showed high-performance, reliable, robust, repeatable, and reproducible results, which are sufficient for paternity testing, individual identification, and use for potentially degraded samples in forensic science.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Repetições de Microssatélites , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA/métodos , Adulto , Povo Asiático/etnologia , Criança , Feminino , Sequenciamento de Nucleotídeos em Larga Escala/instrumentação , Humanos , Masculino , Reação em Cadeia da Polimerase Multiplex , Gravidez , Reprodutibilidade dos Testes , Análise de Sequência de DNA/instrumentação
11.
J Nanobiotechnology ; 19(1): 307, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34620160

RESUMO

BACKGROUND: As one of the leading threats for health among women worldwide, breast cancer has high morbidity and mortality. Surgical resection is the major clinical intervention for primary breast tumor, nevertheless high local recurrence risk and breast tissue defect remain two main clinical dilemmas, seriously affecting survival and quality of life of patients. EXPERIMENTAL: We developed a thermoresponsive and injectable hybrid hydrogel platform (IR820/Mgel) by integration of co-loaded porous microspheres (MPs) and IR820 for preventing postoperative recurrence of breast cancer via photothermal therapy and promoting subsequent breast reconstruction. RESULTS: Our results suggested that IR820/Mgel could quickly heated to more than 50.0 â„ƒ under NIR irradiation, enabling killing effect on 4T1 cells in vitro and prevention effect on post-surgical tumor recurrence in vivo. In addition, the hydrogel platform was promising for its minimal invasion and capability of filling irregularly shaped defects after surgery, and the encapsulated MPs could help to increase the strength of gel to realize a long-term in situ function in vivo, and promoted the attachment and anchorage property of normal breast cells and adipose stem cells. CONCLUSIONS: This photothermal hydrogel platform provides a practice paradigm for preventing locally recurrence of breast cancer and a potential option for reconstruction of breast defects.


Assuntos
Neoplasias da Mama , Hidrogéis , Mamoplastia , Recidiva Local de Neoplasia/prevenção & controle , Fototerapia , Animais , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Verde de Indocianina/análogos & derivados , Verde de Indocianina/química , Verde de Indocianina/farmacologia , Camundongos , Camundongos Endogâmicos BALB C
12.
Int J Mol Sci ; 22(12)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203768

RESUMO

Mesembryanthemum crystallinum (common ice plant) is a halophyte species that has adapted to extreme conditions. In this study, we cloned a McHB7 transcription factor gene from the ice plant. The expression of McHB7 was significantly induced by 500 mM NaCl and it reached the peak under salt treatment for 7 days. The McHB7 protein was targeted to the nucleus. McHB7-overexpressing in ice plant leaves through Agrobacterium-mediated transformation led to 25 times more McHB7 transcripts than the non-transformed wild type (WT). After 500 mM NaCl treatment for 7 days, the activities of superoxide dismutase (SOD) and peroxidase (POD) and water content of the transgenic plants were higher than the WT, while malondialdehyde (MDA) was decreased in the transgenic plants. A total of 1082 and 1072 proteins were profiled by proteomics under control and salt treatment, respectively, with 22 and 11 proteins uniquely identified under control and salt stress, respectively. Among the 11 proteins, 7 were increased and 4 were decreased after salt treatment. Most of the proteins whose expression increased in the McHB7 overexpression (OE) ice plants under high salinity were involved in transport regulation, catalytic activities, biosynthesis of secondary metabolites, and response to stimulus. The results demonstrate that the McHB7 transcription factor plays a positive role in improving plant salt tolerance.


Assuntos
Mesembryanthemum/metabolismo , Proteínas de Plantas/metabolismo , Proteômica , Tolerância ao Sal/fisiologia , Sequência de Aminoácidos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Biologia Computacional , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ontologia Genética , Mesembryanthemum/efeitos dos fármacos , Mesembryanthemum/genética , Filogenia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Transporte Proteico/efeitos dos fármacos , Salinidade , Tolerância ao Sal/efeitos dos fármacos , Tolerância ao Sal/genética , Cloreto de Sódio/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética , Frações Subcelulares/metabolismo , Fatores de Transcrição/metabolismo
13.
J Environ Manage ; 220: 126-135, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29777995

RESUMO

In the West, limited government capacity to solve environmental problems has triggered the rise of a variety of "nonstate actors" to supplement government efforts or provide alternative mechanisms for addressing environmental issues. How does this development - along with our efforts to understand it - map onto environmental governance processes in China? China's efforts to address environmental issues reflect institutionalized governance processes that differ from parallel western processes in ways that have major consequences for domestic environmental governance practices and the governance of China "going abroad." China's governance processes blur the distinction between the state and other actors; the "shadow of the state" is a major factor in all efforts to address environmental issues. The space occupied by nonstate actors in western systems is occupied by shiye danwei ("public service units"), she hui tuanti ("social associations") and e-platforms, all of which have close links to the state. Meanwhile, international NGOs and multinational corporations are also significant players in China. As a result, the mechanisms of influence that produce effects in China differ in important ways from mechanisms familiar from the western experience. This conclusion has far-reaching implications for those seeking to address global environmental concerns, given the importance of China's growing economy and burgeoning network of trade relationships.


Assuntos
Política Ambiental , Programas Governamentais , China , Governo , Humanos
14.
Psychon Bull Rev ; 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519758

RESUMO

Recent studies have examined whether the internal selection mechanism functions similarly for perception and visual working memory (VWM). However, the process of how we access and manipulate object representations distributed in a 3D space remains unclear. In this study, we utilized a memory search task to investigate the effect of depth on object selection and manipulation within VWM. The memory display consisted of colored items half positioned at the near depth plane and the other half at the far plane. During memory maintenance, the participants were instructed to search for a target representation and update its color. The results showed that under object-based attention (Experiments 1, 3, and 5), the update time was faster for targets at the near plane than for those at the far plane. This effect was absent in VWM when deploying spatial attention (Experiment 2) and in visual search regardless of the type of attention deployed (Experiment 4). The differential effects of depth on spatial and object-based attention in VWM suggest that spatial attention primarily relied on 2D location information irrespective of depth, whereas object-based attention seemed to prioritize memory representations at the front plane before shifting to the back. Our findings shed light on the interaction between depth perception and the selection mechanisms within VWM in a 3D context, emphasizing the importance of ordinal, rather than metric, spatial information in guiding object-based attention in VWM.

15.
Chem Sci ; 15(23): 8740-8749, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38899277

RESUMO

Rare-earth metal complexes of the parent benzene tetraanion and neutral inverse-sandwich rare-earth metal arene complexes have remained elusive. Here, we report the first neutral inverse-sandwich rare-earth metal complexes of the parent benzene tetraanion supported by a monoanionic ß-diketiminate (BDI) ligand. Reduction of the trivalent rare-earth metal diiodide precursors (BDI)MI2(THF) (BDI = HC(C(Me)N[C6H3-(3-pentyl)2-2,6])2; M = Y, 1-Y; M = Sm, 1-Sm) in benzene or para-xylene by potassium graphite yielded the neutral inverse-sandwich rare-earth metal arene complexes [(BDI)M(THF) n ]2(µ-η6,η6-arene) (M = Y, Sm; arene = benzene, 2-M; arene = para-xylene, 3-M). Single crystal X-ray diffraction, spectroscopic and magnetic characterization studies, together with density functional theory (DFT) calculations confirm that these neutral rare-earth metal arene complexes possess an [M3+-(arene)4--M3+] electronic structure with strong metal-arene δ interactions. The arene exchange reactivity shows that 2-Sm has higher stability than 3-Sm. Furthermore, 2-Sm can behave as a four-electron reductant to reduce unsaturated organic substrates. Particularly, while the reaction of 2-Sm with 1,3,5,7-cyclooctatetraene (COT) yielded (BDI)Sm(η8-COT) (4-Sm), 2-Sm reacted with 1,4-diphenylbutadiyne to afford (BDI)Sm(η4-C4Ph2) (5-Sm), the first rare-earth metallacyclopentatriene complex.

16.
J Proteomics ; 299: 105145, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38431086

RESUMO

Mesembryanthemum crystallinum (common ice plant), a facultative CAM plant, shifts from C3 to CAM photosynthesis under salt stress, enhancing water use efficiency. Here we used transcriptomics, proteomics, and targeted metabolomics to profile molecular changes during the diel cycle of C3 to CAM transition. The results confirmed expected changes associated with CAM photosynthesis, starch biosynthesis and degradation, and glycolysis/gluconeogenesis. Importantly, they yielded new discoveries: 1) Transcripts displayed greater circadian regulation than proteins. 2) Oxidative phosphorylation and inositol methylation may play important roles in initiating the transition. 3) V-type H+-ATPases showed consistent transcriptional regulation, aiding in vacuolar malate uptake. 4) A protein phosphatase 2C, a major component in the ABA signaling pathway, may trigger the C3 to CAM transition. Our work highlights the potential molecular switches in the C3 to CAM transition, including the potential role of ABA signaling. SIGNIFICANCE: The common ice plant is a model facultative CAM plant, and under stress conditions it can shift from C3 to CAM photosynthesis within a three-day period. However, knowledge about the molecular changes during the transition and the molecular switches enabling the transition is lacking. Multi-omic analyses not only revealed the molecular changes during the transition, but also highlighted the importance of ABA signaling, inositol methylation, V-type H+-ATPase in initiating the shift. The findings may explain physiological changes and nocturnal stomatal opening, and inform future synthetic biology effort in improving crop water use efficiency and stress resilience.


Assuntos
Mesembryanthemum , Fotossíntese , Fotossíntese/fisiologia , Mesembryanthemum/metabolismo , Multiômica , Plantas , Inositol/metabolismo , Água/metabolismo
17.
Science ; 384(6693): eadk6742, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38669575

RESUMO

Drugs of abuse are thought to promote addiction in part by "hijacking" brain reward systems, but the underlying mechanisms remain undefined. Using whole-brain FOS mapping and in vivo single-neuron calcium imaging, we found that drugs of abuse augment dopaminoceptive ensemble activity in the nucleus accumbens (NAc) and disorganize overlapping ensemble responses to natural rewards in a cell type-specific manner. Combining FOS-Seq, CRISPR-perturbation, and single-nucleus RNA sequencing, we identified Rheb as a molecular substrate that regulates cell type-specific signal transduction in NAc while enabling drugs to suppress natural reward consumption. Mapping NAc-projecting regions activated by drugs of abuse revealed input-specific effects on natural reward consumption. These findings characterize the dynamic, molecular and circuit basis of a common reward pathway, wherein drugs of abuse interfere with the fulfillment of innate needs.


Assuntos
Homeostase , Núcleo Accumbens , Recompensa , Núcleo Accumbens/metabolismo , Núcleo Accumbens/efeitos dos fármacos , Animais , Camundongos , Neurônios/metabolismo , Drogas Ilícitas/efeitos adversos , Proteína Enriquecida em Homólogo de Ras do Encéfalo/metabolismo , Proteína Enriquecida em Homólogo de Ras do Encéfalo/genética , Masculino , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas c-fos/metabolismo , Proteínas Proto-Oncogênicas c-fos/genética , Transdução de Sinais , Transtornos Relacionados ao Uso de Substâncias , Análise de Célula Única , Cocaína/farmacologia , Cálcio/metabolismo
18.
Adv Mater ; 36(27): e2400763, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38641927

RESUMO

Muscles featuring high frequency and high stroke linear actuation are essential for animals to achieve superior maneuverability, agility, and environmental adaptability. Artificial muscles are yet to match their biological counterparts, due to inferior actuation speed, magnitude, mode, or adaptability. Inspired by the hierarchical structure of natural muscles, artificial muscles are created that are powerful, responsive, robust, and adaptable. The artificial muscles consist of knots braided from 3D printed liquid crystal elastomer fibers and thin heating threads. The unique hierarchical, braided knot structure offers amplified linear stroke, force rate, and damage-tolerance, as verified by both numerical simulations and experiments. In particular, the square knotted artificial muscle shows reliable cycles of actuation at 1Hz in 3000m depth underwater. Potential application is demonstrated by propelling a model boat. Looking ahead, the knotted artificial muscles can empower novel biomedical devices and soft robots to explore various environments, from inside human body to the mysterious deep sea.


Assuntos
Materiais Biomiméticos , Água , Materiais Biomiméticos/química , Água/química , Músculos , Impressão Tridimensional , Robótica , Órgãos Artificiais , Animais , Elastômeros/química , Biomimética/métodos , Cristais Líquidos/química , Humanos
19.
Animals (Basel) ; 13(14)2023 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-37508021

RESUMO

With the birth of next-generation sequencing (NGS) technology, genomic data in public databases have increased exponentially. Unfortunately, exogenous contamination or intracellular parasite sequences in assemblies could confuse genomic analysis. Meanwhile, they can provide a valuable resource for studies of host-microbe interactions. Here, we used a strategy based on DNA barcodes to scan protistan contamination in the GenBank WGS/TSA database. The results showed a total of 13,952 metazoan/animal assemblies in GenBank, where 17,036 contigs were found to be protistan contaminants in 1507 assemblies (10.8%), with even higher contamination rates in taxa of Cnidaria (150/281), Crustacea (237/480), and Mollusca (107/410). Taxonomic analysis of the protists derived from these contigs showed variations in abundance and evenness of protistan contamination across different metazoan taxa, reflecting host preferences of Apicomplexa, Ciliophora, Oomycota and Symbiodiniaceae for mammals and birds, Crustacea, insects, and Cnidaria, respectively. Finally, mitochondrial proteins COX1 and CYTB were predicted from these contigs, and the phylogenetic analysis corroborated the protistan origination and heterogeneous distribution of the contaminated contigs. Overall, in this study, we conducted a large-scale scan of protistan contaminant in genomic resources, and the protistan sequences detected will help uncover the protist diversity and relationships of these picoeukaryotes with Metazoa.

20.
Viruses ; 15(4)2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-37112854

RESUMO

Bats have received increasing attention because of some unique biological features they possess. TRIM is a large family of proteins that participate in diverse cellular functions, such as antiviral immunity, DNA damage repair, tumor suppression, and aging. These functional areas appear to be highly consistent with the special characteristics of bats, such as tolerance to viruses and DNA damage generated in flight, low cancer incidence, and longevity. However, there is still a lack of systematic study of the TRIM family in bats. Here, we explored the TRIM family of bats using the genomes of 16 representative species. The results showed that the bat TRIM family contains 70 members, with 24 under positive selection and 7 duplicated. Additional transcriptomic analysis revealed the tissue-specific expressions of TRIM9, 46, 54, 55, 63, and 72. Additionally, following interferon or viral stimulation, TRIM orthologs associated with antiviral immunity reported in humans were also upregulated in bat cells. The present study systematically analyzed the composition, evolution, and expression of bat TRIM genes. It may provide a theoretical basis for studies of bat TRIM in the fields of antiviral immunity, longevity, and tolerance to DNA damage.


Assuntos
Quirópteros , Vírus , Animais , Humanos , Proteínas com Motivo Tripartido/genética , Vírus/genética , Antivirais/metabolismo , Genoma , Filogenia
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