RESUMO
Motor neurons are the final common pathway1 through which the brain controls movement of the body, forming the basic elements from which all movement is composed. Yet how a single motor neuron contributes to control during natural movement remains unclear. Here we anatomically and functionally characterize the individual roles of the motor neurons that control head movement in the fly, Drosophila melanogaster. Counterintuitively, we find that activity in a single motor neuron rotates the head in different directions, depending on the starting posture of the head, such that the head converges towards a pose determined by the identity of the stimulated motor neuron. A feedback model predicts that this convergent behaviour results from motor neuron drive interacting with proprioceptive feedback. We identify and genetically2 suppress a single class of proprioceptive neuron3 that changes the motor neuron-induced convergence as predicted by the feedback model. These data suggest a framework for how the brain controls movements: instead of directly generating movement in a given direction by activating a fixed set of motor neurons, the brain controls movements by adding bias to a continuing proprioceptive-motor loop.
Assuntos
Drosophila melanogaster , Neurônios Motores , Movimento , Postura , Propriocepção , Animais , Drosophila melanogaster/anatomia & histologia , Drosophila melanogaster/genética , Drosophila melanogaster/fisiologia , Retroalimentação Fisiológica/fisiologia , Cabeça/fisiologia , Modelos Neurológicos , Neurônios Motores/fisiologia , Movimento/fisiologia , Postura/fisiologia , Propriocepção/genética , Propriocepção/fisiologia , MasculinoRESUMO
Anorectal malformation (ARM) is a prevalent early pregnancy digestive tract anomaly. The intricate anatomy of the embryonic cloaca region makes it challenging for traditional high-throughput sequencing methods to capture location-specific information. Spatial transcriptomics was used to sequence libraries of frozen sections from embryonic rats at gestational days (GD) 14 to 16, covering both normal and ARM cases. Bioinformatics analyses and predictions were performed using methods such as WGCNA, GSEA, and PROGENy. Immunofluorescence staining was used to verify gene expression levels. Gene expression data was obtained with anatomical annotations of clusters, focusing on the cloaca region's location-specific traits. WGCNA revealed gene modules linked to normal and ARM cloacal anatomy development, with cooperation between modules on GD14 and GD15. Differential gene expression profiles and functional enrichment were presented. Notably, protein levels of Pcsk9, Hmgb2, and Sod1 were found to be downregulated in the GD15 ARM hindgut. The PROGENy algorithm predicted the activity and interplay of common signaling pathways in embryonic sections, highlighting their synergistic and complementary effects. A competing endogenous RNA (ceRNA) regulatory network was constructed from whole transcriptome data. Spatial transcriptomics provided location-specific cloaca region gene expression. Diverse bioinformatics analyses deepened our understanding of ARM's molecular interactions, guiding future research and providing insights into gene regulation in ARM development.
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Malformações Anorretais , Redes Reguladoras de Genes , Transdução de Sinais , Transcriptoma , Animais , Malformações Anorretais/genética , Malformações Anorretais/metabolismo , Malformações Anorretais/embriologia , Transdução de Sinais/genética , Transcriptoma/genética , Ratos , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Gravidez , Embrião de Mamíferos/metabolismo , Perfilação da Expressão Gênica/métodos , Biologia Computacional/métodos , Ratos Sprague-Dawley , Cloaca/embriologia , Cloaca/metabolismoRESUMO
Oxadiazon (ODZ) is extensively utilized in agricultural fields for weed control owing to its strong effectiveness. However, excessive loading of ODZ in water bodies and agricultural soils can lead to various environmental concerns. Therefore, it is crucial to understand the ODZ metabolic process and associated mechanisms in crops to assess the likelihood of ODZ contamination in the environment. This study aimed to assess the effects of ODZ on the growth and toxicological responses of rice (Oryza sativa). The growth of rice tissues was notably compromised with the increase in ODZ concentrations. RNA sequencing in combination with liquid chromatography-quadrupole-time-of-flight-high-resolution mass spectrometry/mass spectrometry (LC-Q-TOF-HRMS/MS) analysis allowed for the identification of numerous transcriptional components associated with ODZ metabolism. Four libraries comprising rice roots and shoots exposed to ODZ were RNA-sequenced in triplicate. The application of environmentally realistic ODZ concentrations upregulated the expression of 844 genes in shoots and 1476 genes in roots. Gene enrichment analysis revealed the presence of multiple enzymes involved in ODZ metabolism and detoxification. These enzymes play a critical role in mitigating environmental stress and facilitating xenobiotic metabolism. Notably, among differentially expressed genes, several key enzymes were identified, including cytochrome P450s, protein kinases, aminotransferases, and ATP-binding cassette transporters involved in the metabolic process. Using LC-Q-TOF-HRMS/MS, 3 metabolites and 13 conjugates were identified in multiple metabolic pathways involving oxidation, hydrolysis, glycosylation, acetylation, and methylation. This study successfully established a potential link between the specific metabolic products of ODZ and increased activities of their corresponding enzymes. Moreover, this study considerably elucidates the detailed pathways and mechanisms involved in ODZ metabolism. The study findings provide valuable insights into the development of genotypes for reducing ODZ residues in paddy fields and minimizing their accumulation in rice crops.
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Oryza , Oxidiazóis , Oryza/metabolismo , Espectrometria de Massas em Tandem , Agricultura , Cromatografia LíquidaRESUMO
The role of melatonin (MT), an essential phytohormone controlling the physiological and biochemical reactions of plants to biotic and abiotic stress, in alleviating pesticide phytotoxicity remains unclear. This study explores the effects of MT (0 and 200 mg/L) and six doses of fluroxypyr-meptyl (FLUME) (0-0.14 mg/L) on the physiological response of rice (Oryza sativa). FLUME exposure inhibited the growth of rice seedlings, with MT treatment ameliorating this effect. To determine the biochemical processes and catalytic events involved in FLUME breakdown in rice, six rice root and shoot libraries exposed to either FLUME or FLUME-MT were generated and then subjected to RNA-Seq-LC-Q-TOF-HRMS/MS analyses. The results showed that 1510 root genes and 139 shoot genes exhibited higher upregulation in plants treated with an ecologically realistic FLUME concentration and MT than in those treated with FLUME alone. Gene enrichment analysis revealed numerous FLUME-degradative enzymes operating in xenobiotic tolerance to environmental stress and molecular metabolism. Regarding the FLUME degradation process, certain differentially expressed genes were responsible for producing important enzymes, such as cytochrome P450, glycosyltransferases, and acetyltransferases. Four metabolites and ten conjugates in the pathways involving hydrolysis, malonylation, reduction, glycosylation, or acetylation were characterized using LC-Q-TOF-HRMS/MS to support FLUME-degradative metabolism. Overall, external application of MT can increase rice tolerance to FLUME-induced oxidative stress by reducing phytotoxicity and FLUME accumulation. This study provides insights into MT's role in facilitating FLUME degradation, with potential implications for engineering genotypes supporting FLUME degradation in paddy crops.
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Melatonina , Oryza , Oryza/efeitos dos fármacos , Oryza/metabolismo , Oryza/genética , Oryza/crescimento & desenvolvimento , Melatonina/farmacologia , Raízes de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacosRESUMO
Esketamine (ESK) is the S-enantiomer of ketamine racemate (a new psychoactive substance) that can result in illusions, and alter hearing, vision, and proprioception in human and mouse. Up to now, the neurotoxicity caused by ESK at environmental level in fish is still unclear. This work studied the effects of ESK on behaviors and transcriptions of genes in dopamine and GABA pathways in zebrafish larvae at ranging from 12.4 ng L- 1 to 11141.1 ng L- 1 for 7 days post fertilization (dpf). The results showed that ESK at 12.4 ng L- 1 significantly reduced the touch response of the larvae at 48 hpf. ESK at 12.4 ng L- 1 also reduced the time and distance of larvae swimming at the outer zone during light period, which implied that ESK might potentially decrease the anxiety level of larvae. In addition, ESK increased the transcription of th, ddc, drd1a, drd3 and drd4a in dopamine pathway. Similarly, ESK raised the transcription of slc6a1b, slc6a13 and slc12a2 in GABA pathway. This study suggested that ESK could affect the heart rate and behaviors accompanying with transcriptional alterations of genes in DA and GABA pathways at early-staged zebrafish, which resulted in neurotoxicity in zebrafish larvae.
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Dopamina , Ketamina , Humanos , Animais , Camundongos , Dopamina/metabolismo , Dopamina/farmacologia , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Ketamina/metabolismo , Ketamina/farmacologia , Larva , Ácido gama-Aminobutírico/metabolismo , Ácido gama-Aminobutírico/farmacologiaRESUMO
A tunable Janus absorptive frequency-selective reflector (AFSR) utilizing a graphene-based hyperbolic that showcases exceptional doubling octave frequency absorption (DOFA) or tripling octave frequency absorption (TOFA) is proposed. The multi-objective gray wolf optimization algorithm is employed to drive the transfer matrix method, optimizing parameters such as the dielectric permittivity, thickness, and the Fermi level (Ef) to achieve harmonic absorption. By manipulating the Ef of graphene, the dimensions of the absorption band and reflection window can be finely adjusted. Additionally, a frequency-selective reflector is introduced, enabling a seamless transition between selective absorption and transmission by adjusting the Ef. This AFSR represents a groundbreaking approach to achieving DOFA or TOFA while simultaneously offering valuable insights into the design of intelligent AFSRs.
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Anorectal malformations (ARMs) are common birth defects involving congenital structural anomalies of the gastrointestinal tract. As an important component of non-coding RNAs, circular RNAs (circRNAs) widely participate in the digestive system development; however, the specific molecular mechanism of their involvement in ARM occurrence remains obscure. Herein, we generated rat models of ARMs induced by ethylene thiourea. A novel circRNA (circJag1) was screened and identified by RNA-Seq, which is remarkably upregulated in hindgut tissues of ARM rat embryos. In vivo experiments, colocation analysis via fluorescence in situ hybridization, and immunofluorescence further demonstrated that the disordered circJag1/miR-137-3p/Sox9 expression caused a spatiotemporal imbalance in the urorectal septum (URS) of ARMs. In vitro, functional assays confirmed that circJag1 upregulation resulted in the degradation of nuclear ß-catenin, C-myc, and Cyclin D1 in rat intestinal epithelial cells, as well as the promotion of apoptosis and suppression of cell proliferation. Mechanistically, dual-luciferase reporter assay and RNA immunoprecipitation assay indicated that circJag1 acted as a miR-137-3p sponge, thereby inhibiting its repressive effect on its target Sox9. Further experiments showed that a loss of Sox9 abolished the circJag1-mediated increase in apoptosis. In conclusion, aberrantly high circJag1 expression promotes epithelial apoptosis by suppressing the canonical Wnt/ß-catenin pathway via the miR-137-3p/Sox9 axis, which leads to fusion failure of the URS and cloacal membrane, and eventually contributed to ARMs. Our achievements might boost the comprehension of ARM pathogenesis and could provide a novel candidate target for the development of therapies for ARMs to complement surgical treatment.
Assuntos
Malformações Anorretais , Etilenotioureia , MicroRNAs , Ratos , Animais , beta Catenina/genética , beta Catenina/metabolismo , Hibridização in Situ Fluorescente , MicroRNAs/genética , MicroRNAs/metabolismo , Apoptose/genética , Etilenos , Via de Sinalização Wnt/genética , Proliferação de Células/genética , Linhagem Celular TumoralRESUMO
Imidacloprid (IMI) and thiamethoxam (THM) are ubiquitous in aquatic ecosystems. Their negative effects on parental fish are investigated while intergenerational effects at environmentally relevant concentrations remain unclear. In this study, F0 zebrafish exposed to IMI and THM (0, 50, and 500 ng L-1) for 144 days post-fertilization (dpf) was allowed to spawn with two modes (internal mating and cross-mating), resulting in four types of F1 generations to investigate the intergenerational effects. IMI and THM affected F0 zebrafish fecundity, gonadal development, sex hormone and VTG levels, with accumulations found in F0 muscles and ovaries. In F1 generation, paternal or maternal exposure to IMI and THM also influenced sex hormones levels and elevated the heart rate and spontaneous movement rate. LncRNA-mRNA network analysis revealed that cell cycle and oocyte meiosis-related pathways in IMI groups and steroid biosynthesis related pathways in THM groups were significantly enriched in F1 offspring. Similar transcriptional alterations of dmrt1, insl3, cdc20, ccnb1, dnd1, ddx4, cox4i1l, and cox5b2 were observed in gonads of F0 and F1 generations. The findings indicated that prolonged paternal or maternal exposure to IMI and THM could severely cause intergenerational toxicity, resulting in developmental toxicity and endocrine-disrupting effects in zebrafish offspring.
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Exposição Materna , Peixe-Zebra , Animais , Feminino , Humanos , Tiametoxam , EcossistemaRESUMO
A Janus metastructure (MS) assisted by a waveguide structure (WGS) resting on anapole modes and exhibiting direction-dependent behavior has been developed in the terahertz (THz) region. Ultra-broadband absorption is formed by the destructive interference through the anapole as well as Janus trait and is shaped by nested WGS. In this design, vanadium dioxide (VO2) is expected to attain functional transformation from plasmon-induced transparency (PIT) to absorption. The insulating nature of the VO2 results in the creation of the PIT, which is characterized by a wide and high transmission window ranging from 1.944 THz to 2.284 THz, corresponding to the relative bandwidth of 7.4% above 0.9. However, when the VO2 reaches the metallic state, a high absorptivity of 0.921 at 2.154 THz can be implemented in the -z-direction owing to the excitement of the toroidal dipole and electric dipole moments in the near-infrared region. And in the +z-direction, the broadband absorption above 0.9 in the 1.448-2.497 THz range takes shape in virtue of surface plasmon polariton modes, in which intensely localized oscillation of free electrons is confined to the metal-dielectric interface supported by the WGS. Noting that the MS is equipped with a favorable sensitivity to the incidence angle, we develop an ultra-broadband backward absorption in the TM mode from 0.7-10 THz nearly all above 0.9 when the incidence angle changes from 30°-70°. Moreover, owing to the highly symmetrical structure, the MS exhibits exotic polarization angular stability. All the awesome properties make this MS a good candidate for various applications such as in electromagnetic wave steering, spectral analysis, and sensors.
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Congenital anorectal malformations (ARMs) are among the most prominent deformities of the gastrointestinal tract; however, their precise aetiology remains obscure. Immunohistochemistry demonstrated that, in the ARM group, the PPPDE1-positive cells were widely distributed in the hindgut epithelial tissue from GD13 to GD16. Immunofluorescence revealed that most TUNEL-, Bax-, and Cytochrome C (Cyt C)-positive cells overlapped with PPPDE1-positive cells in the urorectal septum (URS). Western blotting and quantitative real-time RT-PCR revealed that PPPDE1 levels were significantly higher in the ARM group from GD13 to GD14 (p < 0.05). IEC-6 cells were transfected with PPPDE1 overexpression plasmid/NC (negative control) or si-PPPDE1/si-NC. Flow cytometry analysis and CCK-8 assay (used to detect apoptosis and proliferation, respectively), as well as western blotting, showed that the levels of PPPDE1 were positively correlated with the pro-apoptotic molecules Bax and Cyt C. Accordingly, aberrantly high expression of PPPDE1 caused a spatiotemporal imbalance in foetal rats with ARMs during hindgut development. Therefore, the upregulation of PPPDE1 may promote epithelial apoptosis and reduce proliferation in the hindgut via the mitochondrial apoptotic pathway. This could affect the fusion of the URS and cloacal membrane, ultimately inhibiting the hindgut development and resulting in ARMs.
Assuntos
Malformações Anorretais/genética , Carbono-Nitrogênio Liases/genética , Trato Gastrointestinal/metabolismo , Proteína X Associada a bcl-2/genética , Animais , Malformações Anorretais/patologia , Apoptose/genética , Proliferação de Células/genética , Citocromos c/genética , Embrião de Mamíferos , Desenvolvimento Fetal/genética , Trato Gastrointestinal/crescimento & desenvolvimento , Trato Gastrointestinal/patologia , Humanos , Mitocôndrias/genética , Ratos , Transdução de Sinais/genética , Ativação Transcricional/genéticaRESUMO
Agricultural use of neonicotinoid insecticides, neuroactive nitroguanidine compounds, has been detected everywhere in the global, posing significant hazard to nontarget organisms. This work studied the developmental neurotoxicity of zebrafish larvae exposed to imidacloprid (IMI) and thiamethoxam (THM), ranging from 0.05 µg L- 1 to 50 µg L- 1 for 35 days. Transcriptions of genes belonging to the behavior, neurodevelopment and cortisol synthesis in zebrafish larvae were monitored. The qPCR data demonstrated that with exposure time increased, the transcription of behavior related genes was down-regulated in both IMI and THM groups, such as macf1, cdh6 and syt10. Additionally, IMI and THM significantly up-regulated the transcriptions of actha, and down-regulated il1rapl1b and pi4k2a at 35 dpf. Importantly, IMI markedly enhanced the transcripiton of gfap, shha, nkx2.2a and nestin in a time dependent manner. This work provided the foundation for understanding zebrafish larvae's neurotoxicity induced by IMI and THM.
Assuntos
Inseticidas , Peixe-Zebra , Animais , Tiametoxam/toxicidade , Larva , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Inseticidas/toxicidade , Inseticidas/análiseRESUMO
The present study investigated the mechanism of total flavonoids from Ampelopsis grossedentata(AGTF) against gouty arthritis(GA) by network pharmacology and experimental validation. The main active ingredients and targets of AGTF, as well as disease targets, were screened out using relevant databases and literature data. The "protein-protein interaction"(PPI) network and "drug-ingredient-target-pathway" network were constructed, and the potential targets and mechanism of AGTF against GA were predicted. The hyperuricemia(HUA) combined with GA model was induced in rats. The gait behaviors of rats were scored, and ankle swelling degree was observed. The uric acid(UA) level and xanthine oxidase(XOD) activity in the rat serum were detected, and the levels of interleukin-1ß(IL-1ß), interleukin-6(IL-6), and tumor necrosis factor-α(TNF-α) were measured. The protein expression of toll-like receptor 4(TLR4), myeloid differentiation factor 88(MyD88), and nuclear factor-kappa B(NF-κB) in the synovial tissues of the rat ankle joint was determined by immunohistochemistry. Ten active ingredients of AGTF and 73 candidate targets of AGTF against GA were screened out by network pharmacology. Eighty-six signaling pathways were enriched, including TNF signaling pathway, NF-κB signaling pathway, TLR signaling pathway, Nod-like receptor signaling pathway, and purine metabolism signaling pathway, which were closely related to AGTF against GA. Animal experimental results showed that AGTF could effectively improve the abnormal gait behaviors of GA rats, relieve ankle inflammation, and reduce ankle joint swelling. In addition, AGTF could significantly reduce UA level, inhibit XOD activity, decrease TNF-α, IL-6, and IL-1ß content, and down-regulate the expression of TLR4, MyD88, and NF-κB in ankle synovial tissues(P<0.05, P<0.01). The results of network pharmacology and experimental validation are consistent, indicating that AGTF exerts its therapeutic effect on GA by regulating UA metabolism, improving abnormal UA level, reducing the release of inflammatory factors, and regulating immunity and the TLR4/MyD88/NF-κB inflammatory pathway.
Assuntos
Ampelopsis , Artrite Gotosa , Flavonoides , Ampelopsis/química , Animais , Artrite Gotosa/tratamento farmacológico , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Proteínas NLR/metabolismo , Ratos , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Ácido Úrico , Xantina OxidaseRESUMO
The phase ratio of a chromatographic system is an important measurement that has long been estimated or calculated, but rarely directly measured. This study utilized a nanoflow liquid chromatography instrument to more accurately measure the phase ratio for a lauryl acrylate porous polymer monolith. Direct measurement of the phase ratio, and its dependence on temperature, allows for a better understanding of the thermodynamics of retention of small analytes. This study investigates the retention of an alkyl benzene series, toluene to octylbenzene, via capillary electrochromatography. The phase ratio was determined to be 0.202 at 303 K and 0.213 at 333 K. Using the directly measured phase ratio, entropic contributions to retention can also be obtained. Therefore, the Gibbs free energy calculations from these measurements and methods can give insight to modes of retention. The free energy of retention for toluene is -3.97 kJ/mol at 303 K and -3.78 kJ/mol at 333 K. The trends for enthalpy, entropy, and Gibbs free energy of transfer show that retention is enthalpically driven in this capillary electrochromatography (CEC) porous polymer monolith system.
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This study reports a case of superficial CD34-positive fibroblastic tumor (SCPFT) in a child and analyze the major known clinicopathological features of SCPFT and other skin mesenchymal tumors, contributing to an accurate diagnosis of this rare disease. We summarize the clinicopathologic features of an 8-year-old girl who was diagnosed with SCPFT and 46 previously reported SCPFT cases. Post-operative histopathologic examination of the current case showed the tumor lesion was well-circumscribed; tumor cells were spindled-to-polygonal with a fascicular pattern; most nuclei displayed hyperchromasia and low mitotic rate; intranuclear pseudoinclusions could be found; and abundant eosinophilic cytoplasm and partial myxoid stroma were observed. Immunohistochemistry revealed strong and diffuse CD34-positivity, vimentin staining positively but no S-100, SMA, NSE, CD31, desmin, cytokeratin, STAT6, ß-catenin, MDM2, or ERG expression. The Ki-67 and CD68 labeling indexes were approximately 1%. There were no rearrangements of PDGFB or PRDM10 tested by FISH. After surgical resection, the patient had no signs of recurrence or metastasis at a 6-month follow-up. The present case is the first that describes SCPFT in children and has significant clinical implications. SCPFT should be differentiated from other skin mesenchymal tumors. The presented compilation of all so far published SCPFT cases will help in diagnosing successfully SCPFT and increasing awareness of this tumor to guide clinical practice.
Assuntos
Antígenos CD34/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias de Tecidos Moles , Neoplasias Torácicas , Criança , Feminino , Humanos , Imuno-Histoquímica , Neoplasias de Tecidos Moles/metabolismo , Neoplasias de Tecidos Moles/patologia , Neoplasias de Tecidos Moles/cirurgia , Neoplasias Torácicas/metabolismo , Neoplasias Torácicas/patologia , Neoplasias Torácicas/cirurgia , Parede TorácicaRESUMO
Rieske proteins play an essential role in electron transfer in the bc 1 complex. Rieske proteins contain a [2Fe-2S] cluster with one iron ligated by two histidines and the other iron ligated by two cysteines. All Rieske proteins have pH-dependent reduction potentials with the histidines ligating the cluster deprotonating in response to increases in pH. The addition of diethylpyrocarbonate (DEPC) modifies deprotonated histidines. The previous studies on the isolated Thermus thermophilus Rieske protein have used large excesses of DEPC, and this study examines what amino acids become modified under different molar equivalents of DEPC to protein. Increasing amounts of DEPC result in more modification, and higher pH values result in faster reaction. Upon modification, the protein also becomes reduced and ~6 equivalents of DEPC are needed for 50% of the reduction to occur. Which amino acids are modified first also points to the most reactive species on the protein. Mass spectrometry analysis shows that lysine 68 is the most reactive amino acid, followed by the ligating histidine 154 and two other surfaces lysines, 76 and 43. The modification of the ligating histidine at low numbers of DEPC equivalents and correlation with a similar number of equivalents needed to reduce the protein shows that this histidine can interact with neighboring groups, and these results can be extended to the protein within the bc 1 complex, where interaction with neighboring residues or molecules may allow reduction to occur. These results may shed light on how Rieske transfers electrons and protons in the bc 1 complex.
Assuntos
Proteínas Ferro-Enxofre/química , Concentração de Íons de Hidrogênio , Proteínas Ferro-Enxofre/isolamento & purificação , Modelos Moleculares , Estrutura Molecular , OxirreduçãoRESUMO
Diallyl trisulfide (DATS), a garlic organosulfide, has shown excellent chemopreventive potential. Cisplatin (DDP) is widely used to treat solid malignant tumors, but causing serious side effects. In the current study, we attempted to elucidate the chemopreventive mechanisms of DATS in human gastric cancer BGC-823 cells in vitro, and to investigate whether DATS could enhance the anti-tumor efficacy of DDP and improve quality of life in BGC-823 xenograft mice in vivo. Treatment with DATS (25-400 µmol/L) dose-dependently inhibited the viability of BGC-823 cells in vitro with an IC50 of 115.2±4.3 µmol/L after 24 h drug exposure. DATS (50-200 µmol/L) induced cell cycle arrest at G2/M phase in BGC-823 cells, which correlated with significant accumulation of cyclin A2 and B1. DATS also induced BGC-823 cell apoptosis, which was accompanied by the modulation of Bcl-2 family members and caspase cascade activation. In BGC-823 xenograft mice, administration of DATS (20-40 mg·kg-1·d-1, ip) dose-dependently inhibited tumor growth and markedly reduced the number of Ki-67 positive cells in tumors. Interestingly, combined administration of DATS (30 mg·kg-1·d-1, ip) with DDP (5 mg/kg, every 5 d, ip) exhibited enhanced anti-tumor activity with fewer side effects. We showed that treatment of BGC-823 cells with DATS in vitro and in vivo significantly activated kinases such as p38 and JNK/MAPK and attenuated the Nrf2/Akt pathway. This study provides evidence that DATS exerts anticancer effects and enhances the antitumor efficacy of DDP, making it a novel candidate for adjuvant therapy for gastric cancer.
Assuntos
Compostos Alílicos/farmacologia , Antineoplásicos/farmacologia , Cisplatino/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Sulfetos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Estrutura Molecular , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/metabolismo , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Proteína Oncogênica v-akt/antagonistas & inibidores , Proteína Oncogênica v-akt/metabolismo , Neoplasias Gástricas/patologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
An optimized metastructure (MS) switchable between ultra-wideband (UWB) angle-insensitive absorption, and transmissive linear-to-circular (LTC) polarization conversion (PC), is proposed, which is a theoretical study. The structural parameters of this MS are optimized by the thermal exchange optimization algorithm. By modulating the chemical potential (µc) of the graphene-based hyperbolic metamaterial embedded in the MS, the MS can achieve UWB absorption in the absorption state and LTC PC in the transmission state. At normal incidence, in the absorption state, the MS exhibits absorptivity exceeding 0.9 within 7-15.45 THz, with a relative bandwidth (RBW) of 75.28%. By elevating µc, an UWB LTC PC is realized, with a RBW of 118.8%, achieving transmittance above 0.9 and the axial ratio below 3 dB. When prioritizing the angular stability, in the absorption state, the MS secures the angular stability of 75° for TE waves and 65° for TM ones. In the transmission state, the angular stability of PC reaches 60°, with RBW = 100.7%. Moreover, by manipulating µc, the tunability of UWB absorption is realized. The optimized MS provides a reference for designing multifunctional intelligent terahertz modulators, with promising application potential in domains like electromagnetic shielding, communication systems, and THz modulation.
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Fluroxypyr-meptyl (FLUME) is heterocyclic herbicide with internal absorption and transmission characteristics. Owing to its low cost and rapid efficacy, it has been widely used to control broad-leaved weeds in wheat, corn, and rice fields. However, the uptake, translocation, accumulation, and metabolism of FLUME in rice seedlings and the extent of oxidative stress induced by it remain largely unknown, which consequently restricts the comprehensive risk assessment of FLUME residues in the environment during rice production. Hence, we systematically investigated the growth and physiological responses of rice to FLUME and analyzed its uptake, translocation, accumulation, and metabolism in rice seedlings. The results indicated that under 0-0.12 mg/L FLUME treatment, only a small proportion of FLUME was translocated upward and accumulated in rice shoots following absorption via roots, with all the translocation factor values being < 1. Moreover, the distribution and enrichment ability of FLUME in rice seedlings were greater in roots than in shoots. Furthermore, we revealed that FLUME accumulation in rice seedlings evidently inhibited their growth and activated the defense system against oxidative stress, with an increase in the activity of antioxidant and detoxifying enzymes. In addition, multiple metabolic reactions of FLUME were observed in rice seedlings, including dehalogenation, hydroxylation, glycosylation, acetylation, and malonylation. Our study provides systematic insights into the uptake, translocation, accumulation, and metabolism of FLUME in rice seedlings as well as the oxidative stress induced by FLUME accumulation, which can help improve FLUME applications and environmental risk assessments in crops.
Assuntos
Oryza , Plântula , Plântula/metabolismo , Oryza/química , Glicolatos/análise , Glicolatos/metabolismo , Estresse Oxidativo , Raízes de Plantas/químicaRESUMO
Calcium sulfate and calcium sulfate-based biomaterials have been widely used in non-load-bearing bone defects for hundreds of years due to their superior biocompatibility, biodegradability, and non-toxicity. However, lower compressive strength and rapid degradation rate are the main limitations in clinical applications. Excessive absorption causes a sharp increase in sulfate ion and calcium ion concentrations around the bone defect site, resulting in delayed wound healing and hypercalcemia. In addition, the space between calcium sulfate and the host bone, resulting from excessively rapid absorption, has adverse effects on bone healing or fusion techniques. This issue has been recognized and addressed. The lack of sufficient mechanical strength makes it challenging to use calcium sulfate and calcium sulfate-based biomaterials in load-bearing areas. To overcome these defects, the introduction of various inorganic additives, such as calcium carbonate, calcium phosphate, and calcium silicate, into calcium sulfate is an effective measure. Inorganic materials with different physical and chemical properties can greatly improve the properties of calcium sulfate composites. For example, the hydrolysis products of calcium carbonate are alkaline substances that can buffer the acidic environment caused by the degradation of calcium sulfate; calcium phosphate has poor degradation, which can effectively avoid the excessive absorption of calcium sulfate; and calcium silicate can promote the compressive strength and stimulate new bone formation. The purpose of this review is to review the poor properties of calcium sulfate and its complications in clinical application and to explore the effect of various inorganic additives on the physicochemical properties and biological properties of calcium sulfate.
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Androgen receptor (AR) agonists have strong endocrine disrupting effects in fish. Most studies mainly investigate AR binding capacity using human AR in vitro. However, there is still few methods to rapidly predict AR agonists in aquatic organisms. This study aimed to screen AR agonists of fish species using machine learning and molecular models in water-relevant list from NORMAN, a network of reference laboratories for monitoring contaminants of emerging concern in the environment. In this study, machine learning approaches (e.g., Deep Forest (DF)), Random Forests and artificial neural networks) were applied to predict AR agonists. Zebrafish, fathead minnow, mosquitofish, medaka fish and grass carp are all important aquatic model organisms widely used to evaluate the toxicity of new pollutants, and the molecular models of ARs from these five fish species were constructed to further screen AR agonists using AlphaFold2. The DF method showed the best performances with 0.99 accuracy, 0.97 sensitivity and 1 precision. The Asn705, Gln711, Arg752, and Thr877 residues in human AR and the corresponding sites in ARs from the five fish species were responsible for agonist binding. Overall, 245 substances were predicted as suspect AR agonists in the five fish species, including, certain glucocorticoids, cholesterol metabolites, and cardiovascular drugs in the NORMAN list. Using machine learning and molecular modeling hybrid methods rapidly and accurately screened AR agonists in fish species, and helping evaluate their ecological risk in fish populations.