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Parkinson's disease (PD) is a debilitating neurodegenerative disorder. Its symptoms are typically treated with levodopa or dopamine receptor agonists, but its action lacks specificity due to the wide distribution of dopamine receptors in the central nervous system and periphery. Here, we report the development of a gene therapy strategy to selectively manipulate PD-affected circuitry. Targeting striatal D1 medium spiny neurons (MSNs), whose activity is chronically suppressed in PD, we engineered a therapeutic strategy comprised of a highly efficient retrograde adeno-associated virus (AAV), promoter elements with strong D1-MSN activity, and a chemogenetic effector to enable precise D1-MSN activation after systemic ligand administration. Application of this therapeutic approach rescues locomotion, tremor, and motor skill defects in both mouse and primate models of PD, supporting the feasibility of targeted circuit modulation tools for the treatment of PD in humans.
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Terapia Genética , Doença de Parkinson , Animais , Humanos , Camundongos , Corpo Estriado/metabolismo , Levodopa/uso terapêutico , Levodopa/genética , Neurônios/metabolismo , Doença de Parkinson/genética , Doença de Parkinson/terapia , Primatas , Receptores de Dopamina D1/metabolismo , Modelos Animais de DoençasRESUMO
During development, melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs) become light sensitive much earlier than rods and cones. IpRGCs project to many subcortical areas, whereas physiological functions of these projections are yet to be fully elucidated. Here, we found that ipRGC-mediated light sensation promotes synaptogenesis of pyramidal neurons in various cortices and the hippocampus. This phenomenon depends on activation of ipRGCs and is mediated by the release of oxytocin from the supraoptic nucleus (SON) and the paraventricular nucleus (PVN) into cerebral-spinal fluid. We further characterized a direct connection between ipRGCs and oxytocin neurons in the SON and mutual projections between oxytocin neurons in the SON and PVN. Moreover, we showed that the lack of ipRGC-mediated, light-promoted early cortical synaptogenesis compromised learning ability in adult mice. Our results highlight the importance of light sensation early in life on the development of learning ability and therefore call attention to suitable light environment for infant care.
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Ocitocina , Células Ganglionares da Retina , Animais , Encéfalo/metabolismo , Humanos , Camundongos , Células Ganglionares da Retina/fisiologia , Opsinas de Bastonetes/metabolismoRESUMO
Mammals cannot see light over 700 nm in wavelength. This limitation is due to the physical thermodynamic properties of the photon-detecting opsins. However, the detection of naturally invisible near-infrared (NIR) light is a desirable ability. To break this limitation, we developed ocular injectable photoreceptor-binding upconversion nanoparticles (pbUCNPs). These nanoparticles anchored on retinal photoreceptors as miniature NIR light transducers to create NIR light image vision with negligible side effects. Based on single-photoreceptor recordings, electroretinograms, cortical recordings, and visual behavioral tests, we demonstrated that mice with these nanoantennae could not only perceive NIR light, but also see NIR light patterns. Excitingly, the injected mice were also able to differentiate sophisticated NIR shape patterns. Moreover, the NIR light pattern vision was ambient-daylight compatible and existed in parallel with native daylight vision. This new method will provide unmatched opportunities for a wide variety of emerging bio-integrated nanodevice designs and applications. VIDEO ABSTRACT.
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Nanopartículas/uso terapêutico , Células Fotorreceptoras de Vertebrados/fisiologia , Visão Ocular/fisiologia , Animais , Feminino , Raios Infravermelhos , Injeções/métodos , Luz , Masculino , Mamíferos/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Opsinas/metabolismo , Retina/metabolismo , Retina/fisiologia , Células Fotorreceptoras Retinianas Cones/fisiologia , Visão Ocular/genéticaRESUMO
The coexistence of superconductivity and ferromagnetism is an intrinsically interesting research focus in condensed matter physics, but the study is limited by low superconducting (Tc) and magnetic (Tm) transition temperatures in related materials. Here, we used a scanning superconducting quantum interference device to image the in situ diamagnetic and ferromagnetic responses of RbEuFe4As4 with high Tc and Tm. We observed significant suppression of the superfluid density in the vicinity of the magnetic phase transition, signifying fluctuation-enhanced magnetic scatterings between Eu spins and Fe 3d conduction electrons. Intriguingly, we observed multiple ferromagnetic domains that should be absent in an ideal magnetic helical phase. The formation of these domains demonstrates a weak c-axis ferromagnetic component probably arising from the Eu spin-canting effect, indicative of possible superconductivity-driven domain Meissner and domain vortex-antivortex phases, as revealed in EuFe2(As0.79P0.21)2. Our observations highlight that RbEuFe4As4 is a unique system that includes multiple interplay channels between superconductivity and ferromagnetism.
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We report the synthesis, crystal structure, and physical properties of a novel ternary compound, Th2Cu4As5. The material crystallizes in a tetragonal structure with lattice parameters a = 4.0639(3) Å and c = 24.8221(17) Å. Its structure can be described as an alternating stacking of fluorite-type Th2As2 layers with antifluorite-type double-layered Cu4As3 slabs. The measurement of electrical resistivity, magnetic susceptibility, and specific heat reveals that Th2Cu4As5 undergoes bulk superconducting transition at 4.2 K. Additionally, all these physical quantities exhibit anomalies at 48 K, accompanied by a sign change in the Hall coefficient, suggesting a charge-density-wave-like (CDW) phase transition. Drawing from both experimental data and band calculations, we propose that the superconducting and CDW-like phase transitions are, respectively, associated with the Cu4As3 slabs and the As plane in the Th2As2 layers.
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This study delivers a thorough analysis of long non-coding RNAs (lncRNAs) in regulating programmed cell death (PCD), vital for neurodegenerative diseases like Alzheimer's disease (AD) and Parkinson's disease (PD). We propose a new framework PCDLnc, and identified 20 significant lncRNAs, including HEIH, SNHG15, and SNHG5, associated with PCD gene sets, which were known for roles in proliferation and apoptosis in neurodegenerative diseases. By using GREAT software, we identified regulatory functions of top lncRNAs in different neurodegenerative diseases. Moreover, lncRNAs cis-regulated mRNAs linked to neurodegeneration, including JAK2, AKT1, EGFR, CDC42, SNCA, and ADIPOQ, highlighting their therapeutic potential in neurodegenerative diseases. A further exploration into the differential expression of mRNA identified by PCDLnc revealed a role in apoptosis, ferroptosis and autophagy. Additionally, protein-protein interaction (PPI) network analysis exposed abnormal interactions among key genes, despite their consistent expression levels between disease and normal samples. The randomforest model effectively distinguished between disease samples, indicating a high level of accuracy. Shared gene subsets in AD and PD might serve as potential biomarkers, along with disease-specific gene sets. Besides, we also found the strong relationship between AD and immune infiltration. This research highlights the role of lncRNAs and their associated genes in PCD in neurodegenerative diseases, offering potential therapeutic targets and diagnostic markers for future study and clinical application.
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G-quadruplex structures within the nuclear genome (nG4) is an important regulatory factor, while the function of G4 in the mitochondrial genome (mtG4) still needs to be explored, especially in human sperms. To gain a better understanding of the relationship between mtG4 and mitochondrial function, it is crucial to develop excellent probes that can selectively visualize and track mtG4 in both somatic cells and sperms. Herein, based on our previous research on purine frameworks, we attempted for the first time to extend the conjugated structure from the C-8 site of purine skeleton and discovered that the purine derivative modified by the C-8 aldehyde group is an ideal platform for constructing near-infrared probes with extremely large Stokes shift (>220 nm). Compared with the compound substituted with methylpyridine (PAP), the molecule substituted with methylthiazole orange (PATO) showed better G4 recognition ability, including longer emission (â¼720 nm), more significant fluorescent enhancement (â¼67-fold), lower background, and excellent photostability. PATO exhibited a sensitive response to mtG4 variation in both somatic cells and human sperms. Most importantly, PATO helped us to discover that mtG4 was significantly increased in cells with mitochondrial respiratory chain damage caused by complex I inhibitors (6-OHDA and rotenone), as well as in human sperms that suffer from oxidative stress. Altogether, our study not only provides a novel ideal molecular platform for constructing high-performance probes but also develops an effective tool for studying the relationship between mtG4 and mitochondrial function in both somatic cells and human sperms.
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Corantes Fluorescentes , Purinas , Humanos , Purinas/química , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Doenças Mitocondriais/metabolismo , Regulação para Cima , Genoma Mitocondrial , Quadruplex G , Mitocôndrias/metabolismo , Raios Infravermelhos , Células HeLaRESUMO
Circular RNAs (circRNAs) play critical roles in the recurrence and progression of non-small-cell lung cancer (NSCLC). This study aimed to investigate the function and underlying mechanism of a novel circRNA (circRPPH1) in NSCLC. Localization of circRPPH1 was determined via FISH assay, while cell proliferation was assessed via CCK8 and colony formation assay. Cell migration and invasion were studied using transwell assay, while binding sites between miR-326 and circRPPH1 or ERBB4 were verified by luciferase reporter, RIP, and RNA pull-down assays. Moreover, xenograft assay was performed to verify the in vivo roles of circRPPH1. Results indicated that circRPPH1 was highly expressed in NSCLC tissues and cells, where circRPPH1 levels were predictive of poor prognosis. The malignant behavior of NSCLC cells was exacerbated by overexpressing circRPPH1, while opposite effects were observed when it was knocked down. Direct interaction between miR-326 and circRPPH1 or ERBB4 was confirmed in NSCLC cells, while rescue experiment results showed that circRPPH1 exerted an oncogenic role via miR-326-ERBB4 signal axis. Moreover, in vitro, growth of NSCLC cells was significantly attenuated following circRPPH1 depletion. The study concluded that circRPPH1 was involved in promoting NSCLC progression via the miR-326/ERBB4 axis, which provided a novel potential target for the diagnosis or treatment of NSCLC.
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The granulosa cells (GCs) of birds are essential for the reproduction and maintenance of populations in nature. Atrazine (ATR) is a potent endocrine disruptor that can interfere with reproductive function in females and Diaminochlorotriazine (DACT) is the primary metabolite of ATR in the organism. Melatonin (MT) is an endogenous hormone with antioxidant properties that plays a crucial role in development of animal germ cells. However, how ATR causes mitochondrial dysfunction, abnormal secretion of steroid hormones, and whether MT prevents ATR-induced female reproductive toxicity remains unclear. Thus, the purpose of this study is to investigate the protective effect of MT against ATR-induced female reproduction. In the present study, the GCs of quail were divided into 6 groups, as follows: C (Serum-free medium), MT (10 µM MT), A250 (250 µM ATR), MA250 (10 µM MT+250 µM ATR), D200 (200 µM DACT) and MD200 (10 µM MT+200 µM DACT), and were cultured for 24 h. The results revealed that ATR prevented GCs proliferation and decreased cell differentiation. ATR caused oxidative damage and mitochondrial dysfunction, leading to disruption of steroid synthesis, which posed a severe risk to GC's function. However, MT supplements reversed these changes. Mechanistically, our study exhibited that the ROS/SIRT1/STAR axis as a target for MT to ameliorate ATR-induced mitochondrial dysfunction and steroid disorders in GCs, which provides new insights into the role of MT in ATR-induced reproductive capacity and species conservation in birds.
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Atrazina , Herbicidas , Melatonina , Doenças Mitocondriais , Animais , Feminino , Atrazina/toxicidade , Atrazina/metabolismo , Células da Granulosa/metabolismo , Herbicidas/toxicidade , Herbicidas/metabolismo , Melatonina/farmacologia , Doenças Mitocondriais/induzido quimicamente , Espécies Reativas de Oxigênio/metabolismo , Sirtuína 1/efeitos dos fármacos , Sirtuína 1/metabolismo , Esteroides/metabolismo , Codorniz/genética , Codorniz/metabolismoRESUMO
Achieving circularly polarized organic ultralong room-temperature phosphorescence (CP-OURTP) with a high luminescent dissymmetry factor (glum ) is crucial for diverse optoelectronic applications. In particular, dynamically controlling the dissymmetry factor of CP-OURTP can profoundly advance these applications, but it is still unprecedented. This study introduces an effective strategy to achieve photoirradiation-driven chirality regulation in a bilayered structure film, which consists of a layer of soft helical superstructure incorporated with a light-driven molecular motor and a layer of room-temperature phosphorescent (RTP) polymer. The prepared bilayered film exhibits CP-OURTP with an emission lifetime of 805â ms and a glum value up to 1.38. Remarkably, the glum value of the resulting CP-OURTP film can be reversibly controlled between 0.6 and 1.38 over 20â cycles by light irradiation, representing the first example of dynamically controlling the glum in CP-OURTP.
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Considerable advances in the role of oxytocin (OT) effect on behavior and the brain network have been made, but the effect of OT on the association between inter-individual differences in functional connectivity (FC) and behavior is elusive. Here, by using a face-perception task and multiple connectome-based predictive models, we aimed to (1) determine whether OT could enhance the association among behavioral performance, resting-state FC (rsFC), and task-state FC (tsFC) and (2) if so, explore the role of OT in enhancing this triangular association. We found that in the OT group, the prediction performance of using rsFC or tsFC to predict task behavior was higher than that of the PL group. Additionally, the correlation coefficient between rsFC and tsFC was substantially higher in the OT group than in the PL group. The strength of these associations could be partly explained by OT altering the brain's FCs related to social cognition and face perception in both the resting and task states, mainly in brain regions such as the limbic system, prefrontal cortex, temporal poles, and temporoparietal junction. Taken together, these results provide novel evidence and a corresponding mechanism for how neuropeptides cause increased associations among inter-individual differences across different levels (e.g., behavior and large-scale brain networks in both resting and task-state), and may inspire future research on the role of neuropeptides in the cross levels association of both clinical and nonclinical use.
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Conectoma , Neuropeptídeos , Humanos , Ocitocina/farmacologia , Encéfalo/diagnóstico por imagem , Conectoma/métodos , Córtex Pré-Frontal , Neuropeptídeos/farmacologia , Imageamento por Ressonância MagnéticaRESUMO
Bladder cancer (BCa), which usually occurs in bladder epithelial cells and is the fifth most common type of cancer in the world. he recurrence rate within 5 years after surgery is 0.8-45% of patients with early bladder cancer. Therefore, finding appropriate drug therapy for patients with bladder cancer can provide a reference for clinical treatment and play an important role in improving the prognosis of patients. In this study, CCK8 assay result showed that the inhibition of bladder cancer cell activity by Curdione and GEM increased with time and dose. Subsequently, CCK8, clone formation assay and Transwell result showed Curdione enhances GEM inhibition of bladder cancer cell activity, clonal formation and migration, these combine therapeutic schedule also could inhibited growth of in vivo xenograft tumors. The comprehensive database showed that CA2 is a potential target genes of Curdione, and Knockdown CA2 enhances GEM induced inhibition of cell proliferation and migration. Based on these advantages, Curdione may be a new type of action drug or adjunct for the treatment of bladder cancer.
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Cadmium (Cd) is widespread globally in the environment as a toxic metal. Although it is well known to induce hepatotoxicity in the cells, defense mechanisms against the detrimental effects of Cd are still unknown. We examined the role of autophagy (a cellular defense mechanism) on Cd-induced cytotoxicity in bird hepatocytes. Primary chicken hepatocytes were cultured with different concentrations (0, 1, 2.5, 5, and 10 µM) of cadmium chloride (CdCl2) for 12 h. We assessed the effects of CdCl2 on the cell viability, antioxidant status, reactive oxygen species (ROS) generation, autophagy response and endoplasmic reticulum (ER) stress. Further, it is also evaluated that insight into underling molecular mechanisms involved in the study. In this study, CdCl2-induce hepatotoxicity was caused by drastically increased ROS generation as well as a reduction level of antioxidant enzymes. It was also demonstrated that marked activation of ER stress markers (GRP78, IRE1, PERK, ATF4, ATF6 and XBP-1 s) was observed. Simultaneously, increased activation of autophagy in low-dose CdCl2 (1 µM) exposed group was observed, but high-dose CdCl2 (10 µM) inhibited autophagy and significantly promoted apoptosis, as indicated by the expression of the autophagy related genes for P62, Beclin-1, ATG3, ATG5, ATG9, and the detection of autophagic vacuoles. Pretreatment with autophagy agonist Rapamycin (RAP) has successfully reduced ROS production, attenuated ER stress and enhanced hepatocytes viability, while the autophagy inhibitor 3-Methyladenine (3-MA) had the opposite effect. Hence, these findings stipulate that Cd could inhibit viability of hepatocytes in a dose-dependent manner. Autophagy relieves hepatotoxicity of Cd via reducing ROS generation and regulating ER stress. We identified autophagy as a novel protective mechanism involved in Cd-mediated chicken hepatotoxicity.
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Cádmio , Doença Hepática Induzida por Substâncias e Drogas , Animais , Cádmio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Galinhas/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Hepatócitos , Estresse Oxidativo , Estresse do Retículo Endoplasmático , Apoptose , Autofagia , Doença Hepática Induzida por Substâncias e Drogas/metabolismoRESUMO
Due to the wide use of atrazine (ATR), the concern has increased regarding the negative impact of ATR on reproduction. Nevertheless, the reproductive effects caused by different exposure concentrations and the severity of toxic damage are poorly understood. In organisms, ATR is metabolized and degraded through phase II enzyme systems, and changes in cytochrome P450 (CYP) enzymes may have a regulatory role in the harm of ATR. However, less information is available on the induction of CYPs by ATR in avian organisms, and even less on its effects on the testis. Birds are exposed to ATR mainly through food residues and contaminated water, the purpose of this study was to examine reproductive toxicity by different exposure concentrations and elaborate metabolic disorders caused by ATR in European quail (Coturnix coturnix). In this study, the quail were given ATR at 50 mg/kg, 250 mg/kg and 500 mg/kg by oral gavage for 45 days, and the testicular weight coefficients, histopathology and ultrastructure of testes, primary biochemical functions, sex steroid hormones, critical protein levels in the testosterone synthesis pathway, the expression of genes involved CYPs, gonad axis and nuclear receptors expression were investigated. Altogether, testicular coefficient decreased significantly in the high-dose group (1.22%) compared with the control group (3.03%) after 45 days of ATR exposure, and ATR is a potent CYP disruptor that acts through the NXRs and steroid receptor subfamily (APND, CAR, ERND and ERα) without a dose-dependent manner. Notably, ATR interfered with the homeostasis of hormones by triggering the expression of hormones on the gonad axis (LH and E2). These results suggest that exposure to ATR can cause testicular toxicity involving accommodative disorder of phase II enzyme and testosterone synthesis in European quail.
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Atrazina , Masculino , Animais , Atrazina/toxicidade , Atrazina/metabolismo , Coturnix/metabolismo , Testículo/metabolismo , Xenobióticos/metabolismo , Codorniz/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Testosterona/metabolismoRESUMO
A cross-sectional study method combined with two types of traditional Chinese medicine(TCM) syndrome differentiation methods was adopted to investigate the clinical symptoms and distribution characteristics of TCM syndromes in patients with pulmonary nodules from the perspectives of number, size, nature, and stability of pulmonary nodules by using the χ~2 test, systematic clustering and Apriori algorithm correlation analysis. The common clinical symptoms of pulmonary nodules were fatigue(77.35%) and irritability(75.40%), and 40 symptoms were clustered into 3 groups(digestive system symptoms, respiratory system symptoms, and emotional and systemic symptoms) and 8 major symptom categories. The proportion of cold and heat in complexity syndrome(63.43%) was higher based on cold-heat syndrome differentiation. The top two syndromes were Qi deficiency syndrome(88.03%) and Qi depression syndrome(83.17%) based on disease syndrome differentiation. Yang deficiency syndrome(60.52%) was more than Yin deficiency syndrome(50.16%). There were higher proportions of phlegm syndrome(78.67%) and Yang deficiency syndrome(69.33%) of so-litary pulmonary nodules in terms of the number of pulmonary nodules. In terms of size, the proportion of phlegm syndrome decreased as the mean diameter of pulmonary nodules increased, while the proportions of Yang deficiency syndrome and blood stasis syndrome increased. The distribution of Qi depression syndrome was more in those with mean diameter<10 mm(85.02%, P=0.044) and cold syndrome was more in those with mean diameter ≥10 mm(16.67%, P=0.024). In terms of the nature of pulmonary nodules, the proportions of Qi depression syndrome and heat syndrome decreased with the increase in solid components of pulmonary nodules, while the proportions of Yin deficiency syndrome and cold and heat in complexity syndrome increased. The blood stasis syndrome accounted for a higher proportion of pulmonary nodules with solid components. In terms of the stability of pulmonary nodules, dampness syndrome(72.97%), blood stasis syndrome(37.84%), and cold and heat in complexity syndrome(70.27%) accounted for higher proportions. In addition, patients with new nodules presented higher proportions in Qi inversion syndrome(52.00%, P=0.007) and cold and heat in complexity syndrome(66.00%, P=0.008). Meanwhile, 11 syndromes were associated and 4 common compound syndromes were obtained(Qi deficiency and depression syndrome, Qi depression and phlegm coagulation syndrome, Qi deficiency and phlegm coagulation syndrome, and Qi deficiency and dampness obstruction syndrome). Qi deficiency syndrome and Qi depression syndrome could be associated with other syndromes. The results show that the main clinical symptoms of pulmonary nodules are fatigue and irritability. The main TCM syndromes of pulmonary nodules are Qi deficiency syndrome, Qi depression syndrome, Yang deficiency syndrome, and cold and heat in complexity syndrome. The distribution of TCM syndromes is significantly correlated with the size of pulmonary nodules and the presence or absence of new nodules. The common compound syndromes are Qi deficiency and depression syndrome, Qi depression and phlegm coagulation syndrome, Qi deficiency and phlegm coagulation syndrome, and Qi deficiency and dampness obstruction syndrome.
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Medicina Tradicional Chinesa , Deficiência da Energia Yin , Humanos , Deficiência da Energia Yin/diagnóstico , Deficiência da Energia Yang/diagnóstico , Estudos Transversais , SíndromeRESUMO
Retinal organoids (ROs) derived from human inducible pluripotent stem cells (hiPSCs) exhibit considerable therapeutic potential. However, current quality control of ROs during in vitro differentiation is largely limited to the detection of molecular markers, often by immunostaining, polymerase chain reaction (PCR) assays and sequencing, often without proper functional assessments. As such, in the current study, we systemically characterized the physiological maturation of photoreceptor-like cells in hiPSC-derived ROs. By performing patch-clamp recordings from photoreceptor-like cells in ROs at distinct differentiation stages (ie, Differentiation Day [D]90, D150, and D200), we determined the electrophysiological properties of the plasma membrane and several characteristic ion channels closely associated with the physiological functions of the photoreceptors. Ionic hallmarks, such as hyperpolarization-activated cyclic nucleotide-gated (HCN) channels and cyclic nucleotide-gated (CNG) channels, matured progressively during differentiation. After D200 in culture, these characteristic currents closely resembled those in macaque or human native photoreceptors. Furthermore, we demonstrated that the hyperpolarization-activated inward current/depolarization-activated outward current ratio (I-120 /I+40 ), termed as the inward-outward current (IOC) ratio hereon, accurately represented the maturity of photoreceptors and could serve as a sensitive indicator of pathological state. Thus, this study provides a comprehensive dataset describing the electrophysiological maturation of photoreceptor-like cells in hiPSC-derived ROs for precise and sensitive quality control during RO differentiation.
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Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Diferenciação Celular , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Organoides/metabolismo , Células Fotorreceptoras , Células-Tronco Pluripotentes/metabolismo , Retina/metabolismoRESUMO
OBJECTIVES: Higher static magnetic field (SMF) enables higher imaging capability in magnetic resonance imaging (MRI), which encourages the development of ultra-high field MRIs above 20 T with a prerequisite for safety issues. However, animal tests of ≥ 20 T SMF exposure are very limited. The objective of the current study is to evaluate mice behaviour consequences of 3.5-23.0 T SMF exposure. METHODS: We systematically examined 112 mice for their short- and long-term behaviour responses to a 2-h exposure of 3.5-23.0 T SMFs. Locomotor activity and cognitive functions were measured by five behaviour tests, including balance beam, open field, elevated plus maze, three-chamber social recognition, and Morris water maze tests. RESULTS: Besides the transient short-term impairment of the sense of balance and locomotor activity, the 3.5-23.0 T SMFs did not have long-term negative effects on mice locomotion, anxiety level, social behaviour, or memory. In contrast, we observed anxiolytic effects and positive effects on social and spatial memory of SMFs, which is likely correlated with the significantly increased CaMKII level in the hippocampus region of high SMF-treated mice. CONCLUSIONS: Our study showed that the short exposures to high-field SMFs up to 23.0 T have negligible side effects on healthy mice and may even have beneficial outcomes in mice mood and memory, which is pertinent to the future medical application of ultra-high field SMFs in MRIs and beyond. KEY POINTS: ⢠Short-term exposure to magnetic fields up to 23.0 T is safe for mice. ⢠High-field static magnetic field exposure transiently reduced mice locomotion. ⢠High-field static magnetic field enhances memory while reduces the anxiety level.
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Campos Magnéticos , Imageamento por Ressonância Magnética , Animais , Cognição , Imageamento por Ressonância Magnética/efeitos adversos , CamundongosRESUMO
We report a new polymorph of LuRuGe, obtained in indium flux. This phase exhibits the noncentrosymmetric ZrNiAl-type structure with the space group P6Ì 2m as determined by single-crystal X-ray diffraction. This polymorph can convert into another centrosymmetric polymorph (TiNiSi-type structure, space group Pnma) at high temperatures. We performed electrical transport, magnetization, and specific heat measurements on this new phase. It shows metallic behavior with a Hall sign change from negative at 2 K to positive at 125 K. LuRuGe exhibits Pauli paramagnetism as the ground state with no local magnetic moments from either the Ru or Lu site. The Debye temperature Θ = 348 K and electronic coefficient γe = 3.6 mJ K-2 mol-1 are extracted from the low-temperature specific heat data in LuRuGe. We also carried out first-principles density functional theory calculations to map out the electronic band structure and density of states. There are several electronic bands crossing the Fermi level, supporting a multiband scenario consistent with the Hall sign change. The density of states around the Fermi level is mainly from Ru 4d and Ge 4p electrons, indicating a strong hybridization between those atomic orbitals.
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For successful reproduction of farmed fish, it is important to understand the relationship between gonadal development and environmental factors such as temperature and photoperiod. In this study, we determined the effects of temperature (T) and photoperiod (Pp) on serum estradiol-17ß (E2) and progesterone (P) contents, gonadosomatic index (GSI), and oocyte development in female tilapia. We used a central composite experimental design and response surface methodology. The experimental ranges were 18-36 °C for T and 0-24 h for Pp. The results show that the quadratic effects of T and Pp were highly significant for serum E2 and P contents, GSI, and the ratio of stage III to stage II oocytes (P < 0.01), and that the linear effects of T and Pp were also significant for these indicators (P < 0.05). The T × Pp interaction significantly affected serum E2 content (P < 0.05). Serum E2 and P content, GSI, and the ratio of stage III to stage II oocytes increased and then decreased with increasing T or Pp. The best combination of T and Pp for egg development was 28.6 °C/14.29 h. We observed the part of ovarian tissue containing stage V oocytes that are about to be discharged. Shortening the photoperiod or lowering the water temperature delayed the development of ovarian tissue so that most oocytes remained at stage II, and there were many atretic follicles. There were significant positive correlations between female GSI and serum E2, P, and the ratio of stage III to stage II oocytes. The results of this study provide a reference for the regulation of temperature and photoperiod to control broodstock gonadal maturation and hormone-induced broodstock spawning.
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Ciclídeos/sangue , Ciclídeos/fisiologia , Fotoperíodo , Temperatura , Animais , Aquicultura/métodos , Estradiol/sangue , Feminino , Oócitos/crescimento & desenvolvimento , Oogênese , Ovário/crescimento & desenvolvimento , Progesterona/sangueRESUMO
Hydroxyapatite (HAp) is the main inorganic component of the bones and teeth, and it possesses bioactivity and biocompatibility. However, due to its poor mechanical performance, slow degradation speed, and lack of diversity in its function, it is difficult to apply HAp alone as a scaffold material for bone tissue engineering. By combining HAp with other types of materials, composite materials with specific properties can be prepared, and the scopes of HAp applications can be expanded. Firstly, we elaborated on the importance, and strengths and weaknesses of HAp for bone tissue engineering biomaterials and then reviewed the research status of HAp composite materials used in bone regeneration. Secondly, about hot research topics in the field of applying HAp composite materials in bone repair, we summarized the representative findings in the field, and discussions and analysis were made accordingly. Finally, we also examined the future development prospects of HAp composite bone repair materials.