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1.
Plant Cell ; 36(5): 1622-1636, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38113879

RESUMO

Cultivated strawberry (Fragaria × ananassa) has a brief history of less than 300 yr, beginning with the hybridization of octoploids Fragaria chiloensis and Fragaria virginiana. Here we explored the genomic signatures of early domestication and subsequent diversification for different climates using whole-genome sequences of 289 wild, heirloom, and modern varieties from two major breeding programs in the United States. Four nonadmixed wild octoploid populations were identified, with recurrent introgression among the sympatric populations. The proportion of F. virginiana ancestry increased by 20% in modern varieties over initial hybrids, and the proportion of F. chiloensis subsp. pacifica rose from 0% to 3.4%. Effective population size rapidly declined during early breeding. Meanwhile, divergent selection for distinct environments reshaped wild allelic origins in 21 out of 28 chromosomes. Overlapping divergent selective sweeps in natural and domesticated populations revealed 16 convergent genomic signatures that may be important for climatic adaptation. Despite 20 breeding cycles since initial hybridization, more than half of loci underlying yield and fruit size are still not under artificial selection. These insights add clarity to the domestication and breeding history of what is now the most widely cultivated fruit in the world.


Assuntos
Domesticação , Fragaria , Genoma de Planta , Fragaria/genética , Genoma de Planta/genética , Melhoramento Vegetal/métodos , Hibridização Genética , Variação Genética , Genômica/métodos , Seleção Genética
2.
Proc Natl Acad Sci U S A ; 120(34): e2302603120, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37579161

RESUMO

Certain transmembrane and membrane-tethered signaling proteins export from cilia as BBSome cargoes via the outward BBSome transition zone (TZ) diffusion pathway, indispensable for maintaining their ciliary dynamics to enable cells to sense and transduce extracellular stimuli inside the cell. Murine Rab-like 2 (Rabl2) GTPase resembles Chlamydomonas Arf-like 3 (ARL3) GTPase in promoting outward TZ passage of the signaling protein cargo-laden BBSome. During this process, ARL3 binds to and recruits the retrograde IFT train-dissociated BBSome as its effector to diffuse through the TZ for ciliary retrieval, while how RABL2 and ARL3 cross talk in this event remains uncertain. Here, we report that Chlamydomonas RABL2 in a GTP-bound form (RABL2GTP) cycles through cilia via IFT as an IFT-B1 cargo, dissociates from retrograde IFT trains at a ciliary region right above the TZ, and converts to RABL2GDP for activating ARL3GDP as an ARL3 guanine nucleotide exchange factor. This confers ARL3GTP to detach from the ciliary membrane and become available for binding and recruiting the phospholipase D (PLD)-laden BBSome, autonomous of retrograde IFT association, to diffuse through the TZ for ciliary retrieval. Afterward, RABL2GDP exits cilia by being bound to the ARL3GTP/BBSome entity as a BBSome cargo. Our data identify ciliary signaling proteins exported from cilia via the RABL2-ARL3 cascade-mediated outward BBSome TZ diffusion pathway. According to this model, hedgehog signaling defect-induced Bardet-Biedl syndrome caused by RABL2 mutations in humans could be well explained in a mutation-specific manner, providing us with a mechanistic understanding behind the outward BBSome TZ passage required for proper ciliary signaling.


Assuntos
Cílios , Proteínas Hedgehog , Humanos , Fatores de Ribosilação do ADP/genética , Fatores de Ribosilação do ADP/metabolismo , Cílios/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Guanosina Trifosfato/metabolismo , Proteínas Hedgehog/metabolismo , Proteínas de Membrana/metabolismo , Transporte Proteico/genética , Proteínas rab de Ligação ao GTP/metabolismo , Chlamydomonas
3.
Proc Natl Acad Sci U S A ; 120(13): e2218819120, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36943875

RESUMO

Certain ciliary transmembrane and membrane-tethered signaling proteins migrate from the ciliary tip to base via retrograde intraflagellar transport (IFT), essential for maintaining their ciliary dynamics to enable cells to sense and transduce extracellular stimuli inside the cell. During this process, the BBSome functions as an adaptor between retrograde IFT trains and these signaling protein cargoes. The Arf-like 13 (ARL13) small GTPase resembles ARL6/BBS3 in facilitating these signaling cargoes to couple with the BBSome at the ciliary tip prior to loading onto retrograde IFT trains for transporting towards the ciliary base, while the molecular basis for how this intricate coupling event happens remains elusive. Here, we report that Chlamydomonas ARL13 only in a GTP-bound form (ARL13GTP) anchors to the membrane for diffusing into cilia. Upon entering cilia, ARL13 undergoes GTPase cycle for shuttling between the ciliary membrane (ARL13GTP) and matrix (ARL13GDP). To achieve this goal, the ciliary membrane-anchored BBS3GTP binds the ciliary matrix-residing ARL13GDP to activate the latter as an ARL13 guanine nucleotide exchange factor. At the ciliary tip, ARL13GTP recruits the ciliary matrix-residing and post-remodeled BBSome as an ARL13 effector to anchor to the ciliary membrane. This makes the BBSome spatiotemporally become available for the ciliary membrane-tethered phospholipase D (PLD) to couple with. Afterward, ARL13GTP hydrolyzes GTP for releasing the PLD-laden BBSome to load onto retrograde IFT trains. According to this model, hedgehog signaling defects associated with ARL13b and BBS3 mutations in humans could be satisfactorily explained, providing us a mechanistic understanding behind BBSome-cargo coupling required for proper ciliary signaling.


Assuntos
Síndrome de Bardet-Biedl , Cílios , Humanos , Cílios/metabolismo , Transporte Proteico/genética , Síndrome de Bardet-Biedl/genética , Proteínas Hedgehog/metabolismo , Proteínas de Membrana/metabolismo , Guanosina Trifosfato/metabolismo , Flagelos/metabolismo
4.
J Immunol ; 210(12): 2001-2015, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37154707

RESUMO

Abundant evidence demonstrates that mechanical stress could induce an inflammatory response in periodontal tissue, but the precise mechanism remains unclear. In the past few years, periodontal ligament cells (PDLCs), as the most force-sensitive cells, have been investigated in depth as local immune cells, associated with activation of inflammasomes and secretion of inflammatory cytokines in response to mechanical stimuli. However, this study innovatively inspected the effect of PDLCs on the other immune cells after stretch loading to reveal the detailed mechanism by which mechanical stimuli initiate immunoreaction in periodontium. In the present study, we found that cyclic stretch could stimulate human PDLCs to secret exosomes and that these exosomes could further induce the increase of phagocytic cells in the periodontium in Sprague-Dawley rats and the M1 polarization of the cultured macrophages (including the mouse macrophage cell line RAW264.7 and the bone marrow-derived macrophages from C57BL/6 mice). Furthermore, the exosomal miR-9-5p was detected to be overexpressed after mechanical stimuli in both in vivo and in vitro experiments and could trigger M1 polarization via the SIRT1/NF-κB signaling pathway in the cultured macrophages. In summary, this study revealed that PDLCs could transmit the mechanobiological signals to immune cells by releasing exosomes and simultaneously enhance periodontal inflammation through the miR-9-5p/SIRT1/NF-κB pathway. We hope that our research can improve understanding of force-related periodontal inflammatory diseases and lead to new targets for treatment.

5.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-38011109

RESUMO

The time-varying brain activity may parallel the disease progression of cerebral glioma. Assessment of brain dynamics would better characterize the pathological profile of glioma and the relevant functional remodeling. This study aims to investigate the dynamic properties of functional networks based on sliding-window approach for patients with left frontal glioma. The generalized functional plasticity due to glioma was characterized by reduced dynamic amplitude of low-frequency fluctuation of somatosensory networks, reduced dynamic functional connectivity between homotopic regions mainly involving dorsal attention network and subcortical nuclei, and enhanced subcortical dynamic functional connectivity. Malignancy-specific functional remodeling featured a chaotic modification of dynamic amplitude of low-frequency fluctuation and dynamic functional connectivity for low-grade gliomas, and attenuated dynamic functional connectivity of the intrahemispheric cortico-subcortical connections and reduced dynamic amplitude of low-frequency fluctuation of the bilateral caudate for high-grade gliomas. Network dynamic activity was clustered into four distinct configuration states. The occurrence and dwell time of the weakly connected state were reduced in patients' brains. Support vector machine model combined with predictive dynamic features achieved an averaged accuracy of 87.9% in distinguishing low- and high-grade gliomas. In conclusion, dynamic network properties are highly predictive of the malignant grade of gliomas, thus could serve as new biomarkers for disease characterization.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Imageamento por Ressonância Magnética , Encéfalo , Glioma/diagnóstico por imagem , Neoplasias Encefálicas/diagnóstico por imagem , Mapeamento Encefálico
6.
Cell Mol Life Sci ; 81(1): 69, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38294557

RESUMO

Fibrosis is a typical aging-related pathological process involving almost all organs, including the heart, kidney, liver, lung, and skin. Fibrogenesis is a highly orchestrated process defined by sequences of cellular response and molecular signals mechanisms underlying the disease. In pathophysiologic conditions associated with organ fibrosis, a variety of injurious stimuli such as metabolic disorders, epigenetic changes, and aging may induce the progression of fibrosis. Sirtuins protein is a kind of deacetylase which can regulate cell metabolism and participate in a variety of cell physiological functions. In this review, we outline our current understanding of common principles of fibrogenic mechanisms and the functional role of SIRT3/6 in aging-related fibrosis. In addition, sequences of novel protective strategies have been identified directly or indirectly according to these mechanisms. Here, we highlight the role and biological function of SIRT3/6 focus on aging fibrosis, as well as their inhibitors and activators as novel preventative or therapeutic interventions for aging-related tissue fibrosis.


Assuntos
Sirtuína 3 , Sirtuínas , Humanos , Fígado , Fibrose
7.
J Am Chem Soc ; 146(9): 5964-5976, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38381843

RESUMO

Fluorinated ethers have become promising electrolyte solvent candidates for lithium metal batteries (LMBs) because they are endowed with high oxidative stability and high Coulombic efficiencies of lithium metal stripping/plating. Up to now, most reported fluorinated ether electrolytes are -CF3-based, and the influence of ion solvation in modifying degree of fluorination has not been well-elucidated. In this work, we synthesize a hexacyclic coordinated ether (1-methoxy-3-ethoxypropane, EMP) and its fluorinated ether counterparts with -CH2F (F1EMP), -CHF2 (F2EMP), or -CF3 (F3EMP) as terminal group. With lithium bis(fluorosulfonyl)imide as single salt, the solvation structure, Li-ion transport behavior, lithium deposition kinetics, and high-voltage stability of the electrolytes were systematically studied. Theoretical calculations and spectra reveal the gradually reduced solvating power from nonfluorinated EMP to fully fluorinated F3EMP, which leads to decreased ionic conductivity. In contrast, the weakly solvating fluorinated ethers possess higher Li+ transference number and exchange current density. Overall, partially fluorinated -CHF2 is demonstrated as the desired group. Further full cell testing using high-voltage (4.4 V) and high-loading (3.885 mAh cm-2) LiNi0.8Co0.1Mn0.1O2 cathode demonstrates that F2EMP electrolyte enables 80% capacity retention after 168 cycles under limited Li (50 µm) and lean electrolyte (5 mL Ah-1) conditions and 129 cycles under extremely lean electrolyte (1.8 mL Ah-1) and the anode-free conditions. This work deepens the fundamental understanding on the ion transport and interphase dynamics under various degrees of fluorination and provides a feasible approach toward the design of fluorinated ether electrolytes for practical high-voltage LMBs.

8.
J Neurovirol ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575831

RESUMO

Persistent inflammation is described in people with HIV (PWH) on antiretroviral treatment (ART). Early ART initiation is associated with reduced inflammation. We aimed to evaluate neuroinflammation, using translocator protein (TSPO) [11C]PBR28 PET neuroimaging in PWH who initiated ART during acute HIV (aPWH) versus chronic HIV infection (cPWH) versus a control population. This was a cross-sectional, observational study. All participants underwent [11C]PBR28 PET-CT neuroimaging. Using a two-tissue compartment model, total volume of distribution (VT) and distribution volume ratios (DVR) using cortical grey matter as a pseudo-reference region at 20 regions of interest (ROIs) were calculated. Differences in VT and DVR were compared between groups using the Kruskall-Wallis test. Seventeen neuro-asymptomatic male PWH on ART (9 aPWH, 8 cPWH) and 8 male control participants (CPs) were included. Median (interquartile range, IQR) age was 40 (30, 46), 44 (41, 47) and 21 (20, 25) years in aPWH, cPWH and CPs, respectively. Median (IQR) CD4 (cells/µL) and CD4:CD8 were 687 (652, 1014) and 1.37 (1.24, 1.42), and 700 (500, 720) and 0.67 (0.64, 0.82) in aPWH and cPWH, respectively. Overall, no significant difference in VT and DVR were observed between the three groups at any ROIs. cPWH demonstrated a trend towards higher mean VT compared with aPWH and CPs at most ROIs. No significant differences in neuroinflammation, using [11C]PBR28 binding as a proxy, were identified between cPWH, aPWH and CPs. A trend towards lower absolute [11C]PBR28 binding was seen amongst aPWH and CPs, suggesting early ART may mitigate neuroinflammation.

9.
Cereb Cortex ; 33(17): 9764-9777, 2023 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-37464883

RESUMO

Making hand movements in response to visual cues is common in daily life. It has been well known that this process activates multiple areas in the brain, but how these neural activations progress across space and time remains largely unknown. Taking advantage of intracranial electroencephalographic (iEEG) recordings using depth and subdural electrodes from 36 human subjects using the same task, we applied single-trial and cross-trial analyses to high-frequency iEEG activity. The results show that the neural activation was widely distributed across the human brain both within and on the surface of the brain, and focused specifically on certain areas in the parietal, frontal, and occipital lobes, where parietal lobes present significant left lateralization on the activation. We also demonstrate temporal differences across these brain regions. Finally, we evaluated the degree to which the timing of activity within these regions was related to sensory or motor function. The findings of this study promote the understanding of task-related neural processing of the human brain, and may provide important insights for translational applications.


Assuntos
Sinais (Psicologia) , Mãos , Humanos , Encéfalo/fisiologia , Movimento/fisiologia , Mapeamento Encefálico/métodos , Eletroencefalografia/métodos
10.
Proc Natl Acad Sci U S A ; 118(35)2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34446551

RESUMO

Many G protein-coupled receptors and other signaling proteins localize to the ciliary membrane for regulating diverse cellular processes. The BBSome composed of multiple Bardet-Biedl syndrome (BBS) proteins is an intraflagellar transport (IFT) cargo adaptor essential for sorting signaling proteins in and/or out of cilia via IFT. Leucine zipper transcription factor-like 1 (LZTFL1) protein mediates ciliary signaling by controlling BBSome ciliary content, reflecting how LZTFL1 mutations could cause BBS. However, the mechanistic mechanism underlying this process remains elusive thus far. Here, we show that LZTFL1 maintains BBSome ciliary dynamics by finely controlling BBSome recruitment to the basal body and its reassembly at the ciliary tip simultaneously in Chlamydomonas reinhardtii LZTFL1 directs BBSome recruitment to the basal body via promoting basal body targeting of Arf-like 6 GTPase BBS3, thus deciding the BBSome amount available for loading onto anterograde IFT trains for entering cilia. Meanwhile, LZTFL1 stabilizes the IFT25/27 component of the IFT-B1 subcomplex in the cell body so as to control its presence and amount at the basal body for entering cilia. Since IFT25/27 promotes BBSome reassembly at the ciliary tip for loading onto retrograde IFT trains, LZTFL1 thus also directs BBSome removal out of cilia. Therefore, LZTFL1 dysfunction deprives the BBSome of ciliary presence and generates Chlamydomonas cells defective in phototaxis. In summary, our data propose that LZTFL1 maintains BBSome dynamics in cilia by such a dual-mode system, providing insights into how LZTFL1 mediates ciliary signaling through maintaining BBSome ciliary dynamics and the pathogenetic mechanism of the BBS disorder as well.


Assuntos
Chlamydomonas reinhardtii/fisiologia , Cílios/fisiologia , Fototaxia , Fatores de Transcrição/fisiologia , Síndrome de Bardet-Biedl , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Ligação Proteica , Transdução de Sinais
11.
J Cell Physiol ; 238(3): 549-565, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36852649

RESUMO

Certain ciliary transmembrane and membrane-associated signaling proteins export from cilia as intraflagellar transport (IFT) cargoes in a BBSome-dependent manner. Upon reaching the ciliary tip via anterograde IFT, the BBSome disassembles before being reassembled to form an intact entity for cargo phospholipase D (PLD) coupling. During this BBSome remodeling process, Chlamydomonas Rab-like 4 GTPase IFT27, by binding its partner IFT25 to form the heterodimeric IFT25/27, is indispensable for BBSome reassembly. Here, we show that IFT27 binds IFT25 in an IFT27 nucleotide-independent manner. IFT25/27 and the IFT subcomplexes IFT-A and -B are irrelevant for maintaining the stability of one another. GTP-loading onto IFT27 enhances the IFT25/27 affinity for binding to the IFT-B subcomplex core IFT-B1 entity in cytoplasm, while GDP-bound IFT27 does not prevent IFT25/27 from entering and cycling through cilia by integrating into IFT-B1. Upon at the ciliary tip, IFT25/27 cycles on and off IFT-B1 and this process is irrelevant with the nucleotide state of IFT27. During BBSome remodeling at the ciliary tip, IFT25/27 promotes BBSome reassembly independent of IFT27 nucleotide state, making postremodeled BBSomes available for PLD to interact with. Thus, IFT25/27 facilitates BBSome-dependent PLD export from cilia via controlling availability of intact BBSomes at the ciliary tip, while IFT27 nucleotide state does not participate in this regulatory event.


Assuntos
Chlamydomonas , Cílios , Nucleotídeos , Fosfolipase D , Proteínas rab de Ligação ao GTP , Cílios/química , Cílios/metabolismo , Flagelos/química , Flagelos/metabolismo , Fosfolipase D/metabolismo , Transporte Proteico , Transdução de Sinais , Chlamydomonas/citologia , Chlamydomonas/enzimologia , Chlamydomonas/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Guanosina Trifosfato/metabolismo , Guanosina Difosfato/metabolismo
12.
Neuropathol Appl Neurobiol ; 49(3): e12913, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37209022

RESUMO

AIM: The functions of the interlaminar astrocytes in layer I of the human cortex are currently unknown. Here, we aimed to explore whether there is any morphological remodelling of interlaminar astrocytes in layer I of the temporal cortex in epilepsy. METHODS: Tissues were obtained from 17 epilepsy surgery patients and 17 post-mortem age-matched controls. In addition, 10 Alzheimer's disease (AD) patients and 10 age-matched controls were used as the disease control group. Paraffin sections (6 µm) and frozen sections (35 or 150 µm) of inferior temporal gyrus tissue were used for immunohistochemistry. With the use of tissue transparency, 3D reconstruction and hierarchical clustering, we performed a quantitative morphological analysis of astrocytes. RESULTS: Upper and lower zones were identified in layer I of the human cortex. Compared with the astrocytes in layers IV-V, layer I interlaminar astrocytes occupied a significantly smaller volume and exhibited shorter and fewer process intersections. Increased Chaslin's gliosis (consisting of types I and II subpial interlaminar astrocytes) and number of glial fibrillary acidic protein (GFAP)-immunoreactive interlaminar astrocytes in layer I of the temporal cortex were confirmed in patients with epilepsy. There was no difference in the number of interlaminar astrocytes in layer I between AD and age-matched control groups. Using tissue transparency and 3D reconstruction technology, the astrocyte domain in the human temporal cortex was classified into four clusters, among which the interlaminar astrocytes in cluster II were more abundant in epilepsy, showing specific topological structures in patients with epilepsy. Furthermore, there was a significant increase in the astrocyte domain of interlaminar cells in layer I of the temporal cortex in patients with epilepsy. CONCLUSION: The observed significant astrocytic structural remodelling in the temporal cortex of epilepsy patients showed that the astrocyte domain in layer I may play an important role in temporal lobe epilepsy.


Assuntos
Epilepsia do Lobo Temporal , Epilepsia , Humanos , Astrócitos/metabolismo , Epilepsia/metabolismo , Lobo Temporal/metabolismo , Córtex Cerebral/metabolismo , Epilepsia do Lobo Temporal/metabolismo
13.
Phys Chem Chem Phys ; 25(12): 8676-8683, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36892054

RESUMO

Exploring two-dimensional (2D) van der Waals materials with out-of-plane polarization and electromagnetic coupling is essential for the development of next-generation nano-memory devices. A novel class of 2D monolayer materials with predicted spin-polarized semi-conductivity, partially compensated antiferromagnetic (AFM) order, fairly high Curie temperature, and out-of-plane polarization is analyzed in this work for the first time. Based on density functional theory calculations, we systematically studied these properties in asymmetrically functionalized MXenes (Janus Mo2C)-Mo2CXX' (X, X' = F, O, and OH). Using ab initio molecular dynamics (AIMD) and phonon spectrum calculations, the thermal and dynamic stabilities of six functionalized Mo2CXX' were identified. Our DFT+U calculation results also provided a switching path for out-of-plane polarizations, where the reverse of electric polarization is driven by terminal-layer atom flipping. More importantly, strong coupling between magnetization and electric polarization originating from spin-charge interactions was observed in this system. Our results confirm that Mo2C-FO would be a novel monolayer electromagnetic material, and its magnetization can be modulated by electric polarization.

14.
BMC Cardiovasc Disord ; 23(1): 74, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36755219

RESUMO

BACKGROUND: Chronic kidney disease (CKD) patients sustain a fairly high prevalence of cardiovascular disease (CVD). Microvascular inflammation is an early manifestation of CVD, and the released mitochondrial DNA (MtDNA) has been proposed to be a crucial integrator of inflammatory signals. Herein, the aim of this study was to determine the relationship between CVD, microvessel, and circulating MtDNA in the settings of uremia. METHODS: Forty-two maintenance hemodialysis (MHD) patients and 36 health controls were enrolled in this study. Plasma cell-free MtDNA was detected by TaqMan-based qPCR assay. CVD risk markers including high-sensitive C-reactive protein (Hs-CRP), monocyte chemoattractant protein-1 (MCP-1), fibrinogen, and erythrocyte sedimentation rate (ESR) were measured by standard assays. Ten-year CVD risk was calculated from the Framingham risk score (FRS) model. In vitro study, human cardiac microvascular endothelial cells (HCMECs) were incubated with normal or uremic serum, with or without exogenous MtDNA. Intracellular toll-like receptor 9 (TLR9), adhesion molecule 1 (ICAM-1), MCP-1 and tumor necrosis factor-α (TNF-α) and cytosolic MtDNA were detected by qPCR. RESULTS: Plasma MtDNA in MHD patients was significantly higher than healthy controls (4.74 vs. 2.41 × 105 copies/mL; p = 0.000). Subsequently, the MHD patients were classified into two groups based on the MtDNA median (4.34 × 105 copies/mL). In stratified analyses, the levels of Hs-CRP (5.02 vs. 3.73 mg/L; p = 0.042) and MCP-l (99.97 vs. 64.72 pg/mL; p = 0.008) and FRS (21.80 vs. 16.52; p = 0.016) in the high plasma MtDNA group were higher than those in the low plasma MtDNA group. In vitro study, we found that exogenous MtDNA aggravated uremic serum-induced microvascular inflammation (ICAM-1 and TNF-α) in HCMECs (all p < 0.05). Besides, the addition of MtDNA to the medium resulted in a further increase in cytosolic MtDNA and TLR9 levels in uremic serum-treated cells (all p < 0.05). In patients with MHD, MtDNA levels in plasma were significantly reduced after a single routine hemodialysis (pre 4.47 vs. post 3.45 × 105 copies/mL; p = 0.001) or hemodiafiltration (pre 4.85 vs. post 4.09 × 105 copies/mL; p = 0.001). These two approaches seem similar in terms of MtDNA clearance rate (21.26% vs. 11.94%; p = 0.172). CONCLUSIONS: Overall, the present study suggests that MtDNA released into the circulation under the uremic toxin environment may adversely affect the cardiovascular system by exacerbating microvascular inflammation, and that reducing circulating MtDNA might be a future therapeutic strategy for the prevention of MHD-related CVD.


Assuntos
Doenças Cardiovasculares , Humanos , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/genética , Proteína C-Reativa , Molécula 1 de Adesão Intercelular , Receptor Toll-Like 9 , DNA Mitocondrial/genética , Fator de Necrose Tumoral alfa , Células Endoteliais , Diálise Renal/efeitos adversos , Inflamação , Arritmias Cardíacas/etiologia , Biomarcadores
15.
Environ Res ; 231(Pt 2): 116194, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37217131

RESUMO

Fertilization and rhizosphere selection are key regulators for soil nitrogen (N) cycling and microbiome. Thus, clarifying how the overall N cycling processes and soil microbiome respond to these factors is a prerequisite for understanding the consequences of high inputs of fertilizers, enhancing crop yields, and formulating reasonable nitrogen management strategies under agricultural intensification scenarios. To do this, we applied shotgun metagenomics sequencing to reconstruct N cycling pathways on the basis of abundance and distribution of related gene families, as well as explored the microbial diversity and interaction via high throughput sequencing based on a two-decade fertilization experiment in Loess Plateau of China semiarid area. We found that bacteria and fungi respond divergent to fertilization regimes and rhizosphere selection, in terms of community diversity, niche breadth, and microbial co-occurrence networks. Moreover, organic fertilization decreased the complexity of bacterial networks but increased the complexity and stability of fungal networks. Most importantly, rhizosphere selection exerted more strongly influences on the soil overall nitrogen cycling than the application of fertilizers, accompanied by the increase in the abundance of nifH, NIT-6, and narI genes and the decrease in the abundance of amoC, norC, and gdhA genes in the rhizosphere soil. Furthermore, keystone families screening from soil microbiome (e.g., Sphingomonadaceae, Sporichthyaceae, and Mortierellaceae), which were affected by the edaphic variables, contributed greatly to crop yield. Collectively, our findings emphasize the pivotal roles of rhizosphere selection interacting with fertilization regimes in sustaining soil nitrogen cycling processes in response to decades-long fertilization, as well as the potential importance of keystone taxa in maintaining crop yield. These findings significantly facilitate our understanding of nitrogen cycling in diverse agricultural soils and lay a foundation for manipulating specific microorganisms to regulate N cycling and promote agroecosystem sustainability.


Assuntos
Nitrogênio , Solo , Nitrogênio/análise , Fertilizantes/análise , Microbiologia do Solo , Agricultura , Bactérias/metabolismo
16.
BMC Anesthesiol ; 23(1): 331, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37794331

RESUMO

BACKGROUND: Based on electroencephalogram (EEG) analysis, index of consciousness (IoC) monitoring is a new technique for monitoring anesthesia depth. IoC is divided into IoC1 (depth of sedation) and IoC2 (depth of analgesia). The potential for concurrent monitoring of IoC1 and IoC2 to expedite postoperative convalescence remains to be elucidated. We investigated whether combined monitoring of IoC1 and IoC2 can effectively enhances postoperative recovery compared with bispectral index (BIS) in elderly patients undergoing laparoscopic urological surgery under general anesthesia. METHODS: In this prospective, controlled, double-blinded trail, 120 patients aged 65 years or older were arbitrarily assigned to either the IoC group or the control group (BIS monitoring). All patients underwent blood gas analysis at T1 (before anesthesia induction) and T2 (the end of operation). The Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) were administered to all patients at T0 (1 day before surgery) and T4 (7 days after surgery). Serum concentrations of C-reactive protein (CRP) and glial fibrillary acid protein (GFAP) were assessed at T1, T2, and T3 (24 h after surgery). Postoperative complications and the duration of hospitalization were subjected to comparative evaluation. RESULTS: The incidence of postoperative cognitive dysfunction (POCD) was notably lower in the IoC group (10%) than in the control group (31.7%) (P = 0.003). Postoperative serum CRP and GFAP concentrations exhibited significant differences at time points T2 (CRP: P = 0.000; GFAP: P = 0.000) and T3 (CRP: P = 0.003; GFAP: P = 0.008). Postoperative blood glucose levels (P = 0.000) and the overall rate of complications (P = 0.037) were significantly lower in Group IoC than in Group control. CONCLUSION: The employment of IoC monitoring for the management of elderly surgical patients can accelerate postoperative convalescence by mitigating intraoperative stress and reducing peripheral and central inflammatory injury. TRIAL REGISTRATION: Chinese Clinical Trial Registry Identifier: ChiCTR1900025241 (17/08/2019).


Assuntos
Convalescença , Laparoscopia , Idoso , Humanos , Estado de Consciência , Estudos Prospectivos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Proteína C-Reativa/metabolismo , Anestesia Geral/métodos
17.
Proc Natl Acad Sci U S A ; 117(5): 2496-2505, 2020 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-31953262

RESUMO

Bardet-Biedl syndrome (BBS) is a ciliopathy caused by defects in the assembly or distribution of the BBSome, a conserved protein complex. The BBSome cycles via intraflagellar transport (IFT) through cilia to transport signaling proteins. How the BBSome is recruited to the basal body for binding to IFT trains for ciliary entry remains unknown. Here, we show that the Rab-like 5 GTPase IFT22 regulates basal body targeting of the BBSome in Chlamydomonas reinhardtii Our functional, biochemical and single particle in vivo imaging assays show that IFT22 is an active GTPase with low intrinsic GTPase activity. IFT22 is part of the IFT-B1 subcomplex but is not required for ciliary assembly. Independent of its association to IFT-B1, IFT22 binds and stabilizes the Arf-like 6 GTPase BBS3, a BBS protein that is not part of the BBSome. IFT22/BBS3 associates with the BBSome through an interaction between BBS3 and the BBSome. When both IFT22 and BBS3 are in their guanosine triphosphate (GTP)-bound states they recruit the BBSome to the basal body for coupling with the IFT-B1 subcomplex. The GTP-bound BBS3 likely remains to be associated with the BBSome upon ciliary entry. In contrast, IFT22 is not required for the transport of BBSomes in cilia, indicating that the BBSome is transferred from IFT22 to the IFT trains at the ciliary base. In summary, our data propose that nucleotide-dependent recruitment of the BBSome to the basal body by IFT22 regulates BBSome entry into cilia.


Assuntos
Fatores de Ribosilação do ADP/metabolismo , Corpos Basais/metabolismo , Chlamydomonas reinhardtii/metabolismo , Flagelos/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Fatores de Ribosilação do ADP/genética , Síndrome de Bardet-Biedl/genética , Síndrome de Bardet-Biedl/metabolismo , Chlamydomonas reinhardtii/genética , Cílios/genética , Cílios/metabolismo , Flagelos/genética , GTP Fosfo-Hidrolases/genética , Humanos , Ligação Proteica , Transporte Proteico
18.
Int J Neurosci ; 133(9): 947-958, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34963424

RESUMO

Accurate and rapid segmentation of the hippocampus can help doctors perform intractable temporal lobe epilepsy (TLE) preoperative evaluations to identify good surgical candidates. This study aims to establish a radiomics system for the automatic diagnosis of hippocampal sclerosis with the help of machine learning. A total of 240 cases were analysed to develop a diagnostic model. First, an automatic hippocampal segmentation process was established that exploits a priori knowledge of the relatively fixed location of the hippocampus in brain partitions, as well as a deep-learning segmentation network based on an Attention U-net. Then, we extracted 527 radiomics features from each side of the segmented hippocampus. The iterative sparse representation based on feature selection and a support vector machine classifier were finally used to establish the diagnostic model of hippocampal sclerosis. The diagnostic model consists of two consecutive steps: distinguish hippocampal sclerosis (HS) from normal control (NC) and detect whether the HS is located on the left or right side. When the automatic diagnosis model identified HS and NC, the sensitivity and specificity reached 0.941 and 0.917 in the 10-fold cross-validation set and 0.920 and 0.909 in the independent testing set. When the diagnostic model detected HS lateralization, the sensitivity and specificity reached 0.923 and 0.920 in cross-validation and 0.909 and 0.929 in independent testing. Our results show that the developed radiomics model can help detect TLE patients with hippocampal sclerosis and has the potential to simplify preoperative evaluations and select surgical candidates.


Assuntos
Aprendizado Profundo , Epilepsia do Lobo Temporal , Esclerose Hipocampal , Humanos , Imageamento por Ressonância Magnética/métodos , Epilepsia do Lobo Temporal/diagnóstico por imagem , Epilepsia do Lobo Temporal/cirurgia , Hipocampo/diagnóstico por imagem
19.
Nano Lett ; 22(23): 9621-9629, 2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-36459186

RESUMO

Owing to the high surface area and porosity, metal-organic frameworks (MOFs) could be utilized as both nanocarriers of biopharmaceuticals and nanoreactors to organize cascade biological reactions with great potential in cancer treatment. However, nanoscale MOFs suitable for biomedical applications rely on harsh preparation conditions. Here, we utilized tryptophan to modulate the morphology and optical properties of zeolitic imidazolate framework-8 (ZIF-8) as nanocarrier to efficiently encapsulate the enzyme and mRNA. Under room temperature in an aqueous solution, tryptophan would coordinate with zinc ions to form ZIF-8:Trp with a decreased size from the µm range to sub-200 nm. In addition, cargo release could be monitored in real time via fluorescence red-shift effects. Besides being used as nanocarriers of biomolecules, ZIF-8:Trp could also be utilized as nanoreactors to induce cascade reactions to produce reactive oxygen and nitrogen species. Overall, this nanosized ZIF-8:Trp could provide a new strategy for preparation of cascade bioreactions and provide new insight for gas therapy.


Assuntos
Estruturas Metalorgânicas , Zeolitas , Triptofano , Nitrogênio , Oxigênio
20.
Neuroimage ; 250: 118969, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35124225

RESUMO

Invasive brain-computer interfaces (BCI) have made great progress in the reconstruction of fine hand movement parameters for paralyzed patients, where superficial measurement modalities including electrocorticography (ECoG) and micro-array recordings are mostly used. However, these recording techniques typically focus on the signals from the sensorimotor cortex, leaving subcortical regions and other cortical regions related to the movements largely unexplored. As an intracranial recording technique for the presurgical assessments of brain surgery, stereo-encephalography (SEEG) inserts depth electrodes containing multiple contacts into the brain and thus provides the unique opportunity for investigating movement-related neural representation throughout the brain. Although SEEG samples neural signals with high spatial-temporal resolutions, its potential of being used to build BCIs has just been realized recently, and the decoding of SEEG activity related to hand movements has not been comprehensively investigated yet. Here, we systematically evaluated the factors influencing the performance of movement decoding using SEEG signals recorded from 32 human subjects performing a visually-cued hand movement task. Our results suggest that multiple regions in both lateral and depth directions present significant neural selectivity to the task, whereas the sensorimotor area, including both precentral and postcentral cortex, carries the richest discriminative neural information for the decoding. The posterior parietal and prefrontal cortex contribute gradually less, but still rich sources for extracting movement parameters. The insula, temporal and occipital cortex also contains useful task-related information for decoding. Under the cortex layer, white matter presents decodable neural patterns but yields a lower accuracy (42.0 ± 0.8%) than the cortex on average (44.2 ± 0.8%, p<0.01). Notably, collectively using neural signals from multiple task-related areas can significantly enhance the movement decoding performance by 6.9% (p<0.01) on average compared to using a single region. Among the different spectral components of SEEG activity, the high gamma and delta bands offer the most informative features for hand movements reconstruction. Additionally, the phase-amplitude coupling strength between these two frequency ranges correlates positively with the performance of movement decoding. In the temporal domain, maximum decoding accuracy is first reached around 2 s after the onset of movement commands. In sum, this study provides valuable insights for the future motor BCIs design employing both SEEG recordings and other recording modalities.


Assuntos
Mapeamento Encefálico/métodos , Interfaces Cérebro-Computador , Eletroencefalografia/métodos , Mãos/fisiologia , Movimento/fisiologia , Adulto , Sinais (Psicologia) , Epilepsia Resistente a Medicamentos/fisiopatologia , Feminino , Humanos , Masculino , Técnicas Estereotáxicas
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