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1.
Nature ; 601(7892): 205-210, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35022592

RESUMO

Fermi liquid theory forms the basis for our understanding of the majority of metals: their resistivity arises from the scattering of well defined quasiparticles at a rate where, in the low-temperature limit, the inverse of the characteristic time scale is proportional to the square of the temperature. However, various quantum materials1-15-notably high-temperature superconductors1-10-exhibit strange-metallic behaviour with a linear scattering rate in temperature, deviating from this central paradigm. Here we show the unexpected signatures of strange metallicity in a bosonic system for which the quasiparticle concept does not apply. Our nanopatterned YBa2Cu3O7-δ (YBCO) film arrays reveal linear-in-temperature and linear-in-magnetic field resistance over extended temperature and magnetic field ranges. Notably, below the onset temperature at which Cooper pairs form, the low-field magnetoresistance oscillates with a period dictated by the superconducting flux quantum, h/2e (e, electron charge; h, Planck's constant). Simultaneously, the Hall coefficient drops and vanishes within the measurement resolution with decreasing temperature, indicating that Cooper pairs instead of single electrons dominate the transport process. Moreover, the characteristic time scale τ in this bosonic system follows a scale-invariant relation without an intrinsic energy scale: h/τ ≈ a(kBT + γµBB), where h is the reduced Planck's constant, a is of order unity7,8,11,12, kB is Boltzmann's constant, T is temperature, µB is the Bohr magneton and γ ≈ 2. By extending the reach of strange-metal phenomenology to a bosonic system, our results suggest that there is a fundamental principle governing their transport that transcends particle statistics.


Assuntos
Elétrons , Supercondutividade , Campos Magnéticos , Metais , Temperatura
2.
Nature ; 582(7811): E5, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32461695

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

3.
Nature ; 576(7785): 91-95, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31802014

RESUMO

Additive manufacturing, often known as three-dimensional (3D) printing, is a process in which a part is built layer-by-layer and is a promising approach for creating components close to their final (net) shape. This process is challenging the dominance of conventional manufacturing processes for products with high complexity and low material waste1. Titanium alloys made by additive manufacturing have been used in applications in various industries. However, the intrinsic high cooling rates and high thermal gradient of the fusion-based metal additive manufacturing process often leads to a very fine microstructure and a tendency towards almost exclusively columnar grains, particularly in titanium-based alloys1. (Columnar grains in additively manufactured titanium components can result in anisotropic mechanical properties and are therefore undesirable2.) Attempts to optimize the processing parameters of additive manufacturing have shown that it is difficult to alter the conditions to promote equiaxed growth of titanium grains3. In contrast with other common engineering alloys such as aluminium, there is no commercial grain refiner for titanium that is able to effectively refine the microstructure. To address this challenge, here we report on the development of titanium-copper alloys that have a high constitutional supercooling capacity as a result of partitioning of the alloying element during solidification, which can override the negative effect of a high thermal gradient in the laser-melted region during additive manufacturing. Without any special process control or additional treatment, our as-printed titanium-copper alloy specimens have a fully equiaxed fine-grained microstructure. They also display promising mechanical properties, such as high yield strength and uniform elongation, compared to conventional alloys under similar processing conditions, owing to the formation of an ultrafine eutectoid microstructure that appears as a result of exploiting the high cooling rates and multiple thermal cycles of the manufacturing process. We anticipate that this approach will be applicable to other eutectoid-forming alloy systems, and that it will have applications in the aerospace and biomedical industries.

4.
Proc Natl Acad Sci U S A ; 119(29): e2205827119, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35858338

RESUMO

Heterogeneous bubble nucleation is one of the most fundamental interfacial processes ranging from nature to technology. There is excellent evidence that surface topology is important in directing heterogeneous nucleation; however, deep understanding of the energetics by which nanoscale architectures promote nucleation is still challenging. Herein, we report a direct and quantitative measurement of single-bubble nucleation on a single silica nanoparticle within a microsized droplet using scanning electrochemical cell microscopy. Local gas concentration at nucleation is determined from finite element simulation at the corresponding faradaic current of the peak-featured voltammogram. It is demonstrated that the criteria gas concentration for nucleation first drops and then rises with increasing nanoparticle radius. An optimum nanoparticle radius around 10 nm prominently expedites the nucleation by facilitating the special topological nanoconfinements that consequently catalyze the nucleation. Moreover, the experimental result is corroborated by our theoretical calculations of free energy change based on the classic nucleation theory. This study offers insights into the impact of surface topology on heterogenous nucleation that have not been previously observed.

5.
Anal Chem ; 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38319065

RESUMO

Deep understanding of the bubble nucleation process is universally important in systems, from chemical engineering to materials. However, due to its nanoscale and transient nature, effective probing of nucleation behavior with a high spatiotemporal resolution is prohibitively challenging. We previously reported the measurement of a single nanobubble nucleation at a nanoparticle using scanning electrochemical cell microscopy, where the bubble nucleation and formation were inferred from the voltammetric responses. Here, we continue the study of heterogeneous bubble nucleation at interfaces by regulating the local nanostructures using silica nanoparticles with a distinct surface morphology. It is demonstrated that, compared to the smooth spherical silica nanoparticles, the raspberry-like nanoparticles can further significantly reduce the nucleation energy barrier, with a critical peak current about 23% of the bare carbon surfaces. This study advances our understanding of how surface nanostructures direct the heterogeneous nucleation process and may offer a new strategy for surface engineering in gas involved energy conversion systems.

6.
Artigo em Inglês | MEDLINE | ID: mdl-39189066

RESUMO

BACKGROUND: Redo-transcatheter aortic valve replacement (TAVR) is a promising treatment for transcatheter aortic valve degeneration, becoming increasingly relevant with an aging population. In redo-TAVR, the leaflets of the initial (index) transcatheter aortic valve (TAV) are displaced vertically when the second TAV is implanted, creating a cylindrical cage that can impair coronary cannulation and flow. Preventing coronary obstruction and maintaining coronary access is essential, especially in young and low-risk patients undergoing TAVR. This study aimed to develop a new leaflet modification strategy using laser ablation to prevent coronary obstruction and facilitate coronary access after repeat TAVR. METHODS: To evaluate the feasibility of the leaflet modification technique using laser ablation, the initial phase of this study involved applying a medical-grade ultraviolet laser for ablation through pericardial tissue. Following this intervention, computational fluid dynamics simulations were utilized to assess the efficacy of the resulting perforations in promoting coronary flow. These simulations played a crucial role in understanding the impact of the modifications on blood flow patterns, ensuring these changes would facilitate the restoration of coronary circulation. RESULTS: Laser ablation of pericardium leaflets was successful, demonstrating the feasibility of creating openings in the TAV leaflets. Flow simulation results show that ablation of index valve leaflets can effectively mitigate the flow obstruction caused by sinus sequestration in redo-TAVR, with the extent of restoration dependent on the number and location of the ablated openings. CONCLUSIONS: Laser ablation could be a viable method for leaflet modification in redo-TAVR, serving as a new tool in interventional procedures.

7.
J Headache Pain ; 25(1): 148, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39261750

RESUMO

BACKGROUND: Migraine is a highly prevalent and complex neurovascular disease. However, the currently available therapeutic drugs often fall to adequately meet clinical needs due to limited effectiveness and numerous undesirable side effects. This study aims to identify putative novel targets for migraine treatment through proteome-wide Mendelian randomization (MR). METHODS: We utilized MR to estimate the causal effects of plasma proteins on migraine and its two subtypes, migraine with aura (MA) and without aura (MO). This analysis integrated plasma protein quantitative trait loci (pQTL) data with genome-wide association studies (GWAS) findings for these migraine phenotypes. Moreover, we conducted a phenome-wide MR assessment, enrichment analysis, protein-protein interaction networks construction, and mediation MR analysis to further validate the pharmaceutical potential of the identified protein targets. RESULTS: We identified 35 protein targets for migraine and its subtypes (p < 8.04 × 10-6), with prioritized targets showing minimal side effects. Phenome-wide MR identified novel protein targets-FCAR, UBE2L6, LATS1, PDCD1LG2, and MMP3-that have no major disease side effects and interacted with current acute migraine medication targets. Additionally, MMP3, PDCD1LG2, and HBQ1 interacted with current preventive migraine medication targets. The causal effects of plasma protein on migraine were partly mediated by plasma metabolites (proportion of mediation from 3.8% to 21.0%). CONCLUSIONS: A set of potential protein targets for migraine and its subtypes were identified. These proteins showed rare side effects and were responsible for biological mechanisms involved in migraine pathogenesis, indicating priority for the development of migraine treatments.


Assuntos
Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Proteoma , Locos de Características Quantitativas , Humanos , Proteoma/efeitos dos fármacos , Transtornos de Enxaqueca/genética , Transtornos de Enxaqueca/tratamento farmacológico , Transtornos de Enxaqueca/sangue , Mapas de Interação de Proteínas/genética , Enxaqueca com Aura/genética , Enxaqueca com Aura/tratamento farmacológico , Enxaqueca com Aura/sangue , Enxaqueca sem Aura/genética , Enxaqueca sem Aura/tratamento farmacológico , Enxaqueca sem Aura/sangue , Proteínas Sanguíneas/genética , Proteínas Sanguíneas/metabolismo
8.
J Headache Pain ; 25(1): 110, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977951

RESUMO

BACKGROUND: New daily persistent headache (NDPH) is a rare primary headache with unclear pathogenesis. Neuroimaging studies of NDPH are limited, and controversy still exists. Diffusion tensor imaging (DTI) is commonly used to study the white matter. However, lacking specificity, the potential pathological mechanisms of white matter microstructural changes remain poorly understood. In addition, the intricacy of gray matter structures impedes the application of the DTI model. Here, we applied an advanced diffusion model of neurite orientation dispersion and density imaging (NODDI) to study the white matter and cortical gray matter microstructure in patients with NDPH. METHODS: This study assessed brain microstructure, including 27 patients with NDPH, and matched 28 healthy controls (HCs) by NODDI. The differences between the two groups were assessed by tract-based spatial statistics (TBSS) and surface-based analysis (SBA), focusing on the NODDI metrics (neurite density index (NDI), orientation dispersion index (ODI), and isotropic volume fraction (ISOVF)). Furthermore, we performed Pearson's correlation analysis between the NODDI indicators and clinical characteristics. RESULTS: Compared to HCs, patients with NDPH had a reduction of density and complexity in several fiber tracts. For robust results, the fiber tracts were defined as comprising more than 100 voxels, including bilateral inferior fronto-occipital fasciculus (IFOF), left superior longitudinal fasciculus (SLF) and inferior longitudinal fasciculus (ILF), as well as right corticospinal tract (CST). Moreover, the reduction of neurite density was uncovered in the left superior and middle frontal cortex, left precentral cortex, and right lateral orbitofrontal cortex and insula. There was no correlation between the NODDI metrics of these brain regions and clinical variables or scales of relevance after the Bonferroni correction. CONCLUSIONS: Our research indicated that neurite loss was detected in both white matter and cortical gray matter of patients with NDPH.


Assuntos
Imagem de Tensor de Difusão , Substância Cinzenta , Substância Branca , Humanos , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Masculino , Adulto , Pessoa de Meia-Idade , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Transtornos da Cefaleia/diagnóstico por imagem , Transtornos da Cefaleia/patologia , Neuritos/patologia
9.
Biomacromolecules ; 24(5): 2075-2086, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-37018617

RESUMO

Development of bioactive bone and joint implants that offer superior mechanical properties to facilitate personalized surgical procedures remains challenging in the field of biomedical materials. As for the hydrogel, mechanical property and processability are major obstructions hampering its application as load-bearing scaffolds in orthopedics. Herein, we constructed implantable composite hydrogels with appealing processability and ultrahigh stiffness. Central to our design is the incorporation of a thixotropic composite network into an elastic polymer network via dynamic interactions to synthesize a percolation-structured double-network (DN) hydrogel with plasticity, followed by in situ strengthening and self-strengthening mechanisms for fostering the DN structure to the cojoined-network structure and subsequently mineralized-composite-network structure to harvest excellent stiffness. The ultrastiff hydrogel is shapeable and can reach a compressive modulus of 80-200 MPa together with a fracture energy of 6-10 MJ/m3, comparable to the mechanical performance of cancellous bone. Moreover, the hydrogel is cytocompatible, osteogenic, and showed almost no volume shrinkage within 28 days in simulated body fluid or culture medium. Such characteristics enabled the utility of a hydrogel in the reduction and stabilization of periarticular fracture treatment on a distal femoral AO/OTA B1 fracture rabbit model and successfully avoided the recollapse of the articular surface.


Assuntos
Materiais Biocompatíveis , Hidrogéis , Animais , Coelhos , Hidrogéis/química , Materiais Biocompatíveis/química , Polímeros/química , Osso e Ossos , Osteogênese
10.
J Headache Pain ; 24(1): 80, 2023 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-37394419

RESUMO

BACKGROUND: New daily persistent headache (NDPH) is a rare primary headache disorder characterized by daily and persistent sudden onset headaches. The pathogenesis of NDPH remains unclear, and there are few white matter imaging studies related to NDPH. The purpose of this study was to investigate the micro-structural abnormalities of white matter in NDPH and provided insights into the pathogenesis of this disease based on tract-based spatial statistics (TBSS). METHODS: Twenty-one patients with NDPH and 25 healthy controls (HCs) were included in this study. T1 structural and diffusion magnetic resonance imaging (MRI) were acquired from all participants. Differences in the fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) between patients with NDPH and HCs were investigated using TBSS analysis. RESULTS: Significantly decreased FA, increased MD and RD were found in patients with NDPH compared to HCs. White matter regions overlaid with decreased FA, increased MD and RD were found in 16 white matter tracts from the Johns Hopkins University ICBM-DTI-81 White-Matter Atlas and Johns Hopkins University White-Matter Tractography Atlas. Specifically, these white matter regions included the right anterior thalamic radiation (ATR), body of the corpus callosum (BCC), bilateral cingulum, left hippocampal cingulum (CGH), left corticospinal tract (CST), forceps major, fornix, left inferior fronto-occipital fasciculus (IFOF), bilateral inferior longitudinal fasciculus (ILF), left posterior limb of the internal capsule (PLIC), right retrolenticular part of the internal capsule (RPIC), splenium of the corpus callosum (SCC), right superior longitudinal fasciculus (SLF) and left uncinate fasciculus (UF). After Bonferroni correction, there were no correlations between the FA, MD, AD and RD values and the clinical characteristics of patients with NDPH (p > 0.05/96). CONCLUSION: The results of our research indicated that patients with NDPH might have widespread abnormalities in the white matter of the brain.


Assuntos
Substância Branca , Humanos , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Imagem de Tensor de Difusão/métodos , Imagem de Difusão por Ressonância Magnética , Fibras Nervosas , Anisotropia , Cefaleia/patologia , Encéfalo
11.
J Headache Pain ; 24(1): 45, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37098498

RESUMO

BACKGROUND: New daily persistent headache (NDPH) is a rare but debilitating primary headache disorder that poses a significant burden on individuals and society. Despite its clinical importance, the underlying pathophysiological mechanisms of NDPH remain unclear. In this study, we aimed to investigate the brain structural changes and neural activity patterns in patients with NDPH using multimodal brain imaging analysis of structural magnetic resonance imaging (sMRI) combined with magnetoencephalography (MEG). METHODS: Twenty-eight patients with NDPH and 37 healthy controls (HCs) were recruited for this study, and their structural and resting-state data were collected by 3.0 Tesla MRI and MEG. We analyzed the brain morphology using voxel-based morphometry and source-based morphometry. In each brain region, MEG sensor signals from 1 to 200 Hz were analyzed using an adapted version of Welch's method. MEG source localization was conducted using the dynamic statistical parametric mapping, and the difference of source distribution between patients with NDPH and HCs was examined. RESULTS: Our results revealed significant differences in the regional grey matter volume, cortical thickness, and cortical surface area between the two groups. Specifically, compared with HCs, patients with NDPH showed a significant decrease in cortical thickness of the left rostral cortex in the middle frontal gyrus, decreased cortical surface area of the left fusiform gyrus, decreased grey matter volume of the left superior frontal gyrus and the left middle frontal gyrus, and increased grey matter volume of the left calcarine. Furthermore, the power of the whole brain, bilateral frontal lobes, and right temporal lobe in the NDPH group were higher than that in HCs in the ripple frequency band (80-200 Hz). Functional and structural analysis suggested that there were structural changes and abnormal high frequency cortical activity in both frontal and temporal lobes in patients with NDPH. CONCLUSION: Our findings indicated that patients with NDPH have abnormalities in brain morphology, such as cortical area, cortical thickness, and grey matter volume, accompanied by abnormal cortical neural activity. Brain structural changes in the frontotemporal cortex and abnormalities in cortical ripple activity may be involved in the pathogenesis of NDPH.


Assuntos
Encéfalo , Magnetoencefalografia , Humanos , Imageamento por Ressonância Magnética/métodos , Córtex Cerebral , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Mapeamento Encefálico , Cefaleia
12.
J Headache Pain ; 24(1): 46, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37098469

RESUMO

BACKGROUND AND PURPOSE: The pathogenesis of new daily persistent headache (NDPH) is not fully understood. We aim to map aberrant functional connectivity (FC) in patients with NDPH using resting-state functional magnetic resonance imaging (MRI). METHODS: Brain structural and functional MRI data were acquired from 29 patients with NDPH and 37 well-matched healthy controls (HCs) in this cross-sectional study. Region of interest (ROI) based analysis was used to compare FC between patients and HCs, with 116 brain regions in the automated anatomical labeling (AAL) atlas were defined as seeds. The correlations between aberrant FC and patients' clinical characteristics, and neuropsychological evaluation were also investigated. RESULTS: Compared with HCs, patients with NDPH showed increased FC in the left inferior occipital gyrus, right thalamus and decreased FC in right lingual gyrus, left superior occipital gyrus, right middle occipital gyrus, left inferior occipital gyrus, right inferior occipital gyrus, right fusiform gyrus, left postcentral gyrus, right postcentral gyrus, right thalamus and right superior temporal gyrus. There were no correlation between FC of these brain regions and clinical characteristics, neuropsychological evaluation after Bonferroni correction (p > 0.05/266). CONCLUSIONS: Patients with NDPH showed aberrant FC in multiple brain regions involved in perception and regulation of emotion and pain. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05334927.


Assuntos
Encéfalo , Transtornos da Cefaleia , Humanos , Estudos Transversais , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Cefaleia
13.
J Headache Pain ; 24(1): 161, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38053071

RESUMO

BACKGROUND: The brain functional network topology in new daily persistent headache (NDPH) is not well understood. In this study, we aim to assess the cortical functional network topological characteristics of NDPH using non-invasive neural signal recordings. METHODS: Resting-state magnetoencephalography (MEG) was used to measure power fluctuations in neuronal oscillations from distributed cortical parcels in 35 patients with NDPH and 40 healthy controls (HCs). Their structural data were collected by 3T MRI. Functional connectivity (FC) of neural networks from 1 to 80 Hz frequency ranges was analyzed with topographic patterns and calculated network topological parameters with graph theory. RESULTS: In the delta (1-4 Hz) and beta (13-30 Hz) bands, the lateral occipital cortex and superior frontal gyrus FC were increased in NDPH groups compared to HCs. Graph theory analysis revealed that the NDPH had significantly increased global efficiency in the delta band and decreased nodal clustering coefficient (left medial orbitofrontal cortex) in the theta (4-8 Hz) band. The clinical characteristics had a significant correlation with network topological parameters. Age at onset of patients showed a positive correlation with global efficiency in the delta band. The degree of depression of patients showed a negative correlation with the nodal clustering coefficient (left medial orbitofrontal cortex) in the theta band. CONCLUSION: The FC and topology of NDPH in brain networks may be altered, potentially leading to cortical hyperexcitability. Moreover, medial orbitofrontal cortex is involved in the pathophysiological mechanism of depression in patients with NDPH. Increased FC observed in the lateral occipital cortex and superior frontal gyrus during resting-state MEG could serve as one of the imaging characteristics associated with NDPH.


Assuntos
Transtornos da Cefaleia , Magnetoencefalografia , Humanos , Mapeamento Encefálico/métodos , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Cefaleia
14.
Eur J Nucl Med Mol Imaging ; 49(8): 2821-2832, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34860277

RESUMO

PURPOSE: Growing evidence proved the efficacy of multi-parametric MRI (mpMRI) and prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT)-guided targeted biopsy (TB) in prostate cancer (PCa) diagnosis, but there is no direct comparison between mpMRI-TB and PSMA PET/CT-TB. Gastrin-releasing peptide receptor (GRPR) is highly expressed in PCa, which can compensate for the unstable expression of PSMA in PCa. Therefore, we designed a study to compare the efficiency of mpMRI-TB, dual-tracer (GRPR and PSMA) PET/CT-TB, systematic biopsy, and combined biopsy for the diagnosis of prostate cancer. METHODS: One hundred twelve suspicious PCa patients were enrolled from September 2020 to June 2021. Patients with anyone of positive dual-tracer PET/CT or mpMRI underwent TB, and all enrolled patients underwent systematic biopsy (SB) after TB. The primary outcome was the detection rates of PCa in different biopsy strategies. Secondary outcomes were the performance of three imaging methods, omission diagnostic rates, and upgrading and downgrading of biopsy samples relative to those of prostatectomy specimens in different biopsy strategies. McNemar's tests and Bonferroni correction in multiple comparisons were used to compare the primary and secondary outcomes. RESULTS: In 112 men, clinically significant PCa (grade group[GG] ≥ 2) accounted for 34.82% (39/112), and nonclinically significant PCa (GG = 1) accounted for 4.46% (5/112). 68 Ga-PSMA PET/CT-TB achieved higher PCa detection rate (69.77%) and positive ratio of biopsy cores (0.44) compared with SB (39.29% and 0.12) and mpMRI-TB (36.14% and 0.23), respectively (P < 0.005). Dual-tracer PET/CT screen out patients for avoiding 52.67% (59/112) unnecessary biopsy, whereas dual-tracer PET/CT-TB plus SB achieved high detection rate (77.36%) without misdiagnosis of csPCa. CONCLUSION: Dual-tracer PET/CT might screen patients for avoiding unnecessary biopsy. Dual-tracer PET/CT-TB plus SB might be a more effective and promising strategy for the definite diagnosis of clinically significant PCa than mpMRI-TB.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata , Biópsia , Radioisótopos de Gálio , Humanos , Biópsia Guiada por Imagem , Masculino , Projetos Piloto , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Neoplasias da Próstata/patologia , Receptores da Bombesina
15.
BMC Cancer ; 22(1): 1128, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329394

RESUMO

BACKGROUND: Nutritional status and inflammation are closely associated with poor outcome in malignant tumors. However, the prognostic impact of postoperative in these variables on breast cancer (BC) remains inconclusive. We aimed to determine whether prognostic nutritional index (PNI), systemic immune-inflammation index (SII), neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) affect two long-term outcomes among patients after curative resection of BC. METHODS: We retrospectively reviewed 508 patients with BC treated with curative surgery between February 5, 2013 and May 26, 2020. All patients were divided into 3 groups based on tertiles (T1-T3) of PNI, SII, NLR, and PLR. The effects of four indexes on disease-free survival (DFS) and overall survival (OS) have been evaluated using Cox proportional hazards models and Kaplan-Meier method. RESULTS: Compared with PNI-lowest cases, patients with highest PNI showed significantly longer DFS (multivariate adjusted hazard ratio [HR] = 0.37, 95% confident interval [CI] 0.19-0.70, P for trend = 0.002), whereas higher PLR seemed to be marginally associated with poorer DFS (P for trend = 0.086 and 0.074, respectively). Subgroup analyses indicate the potential modification effects of family history of BC and radiotherapy on the prognosis value of PNI to DFS in BC patients (P for interaction = 0.004 and 0.025, respectively). In addition, the levels of three inflammatory indices, namely SII, NLR, and PLR might be positively related with increased age at diagnosis (all P for trend < 0.001). CONCLUSIONS: A high PNI was associated with better DFS, supporting its roles as prognostic parameters for patients with BC. The nutritional status and systemic immune may exert great effects on patient prognosis. Further studies are warrant to explore the prognosis value of PLR.


Assuntos
Neoplasias da Mama , Avaliação Nutricional , Humanos , Feminino , Prognóstico , Estudos Retrospectivos , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologia , Linfócitos/patologia , Neutrófilos/patologia , Inflamação/patologia
16.
Exp Eye Res ; 216: 108954, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35074343

RESUMO

This study aimed to investigate the effects of Panax notoginseng saponins (PNS) on the proliferation, apoptosis, and PI3K/AKT signalling pathways of retinoblastoma Y79 cells to explore the possible mechanism of action of PNS on retinoblastoma. The effects of PNS and carboplatin on the proliferation of Y79 cells were examined using cell counting kit-8 assay. And the apoptosis rate, the mRNA and protein levels of apoptosis-related genes and the expression of PI3K/AKT pathway protein were assessed. PNS effectively inhibited the proliferation (P < 0.05) and increased apoptosis of Y79 cells (P < 0.05). Compared with the negative control, the Y79 cells treated with PNS had significantly increased (P < 0.05) mRNA and protein expression of Bax, caspase-3, caspase-8, and caspase-9 and elevated levels of cleaved caspase-3, cleaved caspase-8, and cleaved caspase-9 proteins (P < 0.05). The mRNA and protein expression of the apoptosis suppressor gene Bcl-2 was inhibited (P < 0.05), while the Bax/Bcl-2 values of the cells in the drug group were significantly higher than those in the negative group (P < 0.01). After treatment with PNS, the total protein expression of PI3K and AKT1 in the Y79 cells did not show significant differences compared with the negative group (P > 0.05), although the expression of phosphorylated proteins p-PI3K, p-AKT (Thr308), p-AKT (Ser473), and p-mTOR were significantly reduced (P < 0.05). Meanwhile, the antagonist protein of the pathway phosphatase and tensin homologue deleted on chromosome 10 (PTEN) expression was increased (P < 0.01). Cellular alterations following inhibition of the PI3K/AKT pathway using LY294002 were similar to those of PNS, the proliferation of Y79 cells was also inhibited, and cell apoptosis increased (P < 0.001). The expression of Bax, caspase-3, caspase-8, caspase-9, and activation proteins cleaved caspase-3, cleaved caspase-8, and cleaved caspase-9 was also significantly higher than that in the negative control (P < 0.05). Bcl-2 protein expression was decreased (P < 0.01), and the Bax/Bcl-2 ratio was higher than that in the negative control (P < 0.001). Overall, we demonstrated that PNS effectively inhibited the proliferation and promoted the apoptosis of retinoblastoma Y79 cells. The apoptosis-promoting effect of PNS may involve the inhibition of the PI3K/AKT signalling pathway, which subsequently regulates the expression of apoptosis-related genes.


Assuntos
Apoptose/efeitos dos fármacos , Elafina/genética , Panax notoginseng/química , Proteínas Proto-Oncogênicas c-akt/genética , Neoplasias da Retina/patologia , Retinoblastoma/patologia , Saponinas/farmacologia , Western Blotting , Carboplatina/farmacologia , Proliferação de Células/efeitos dos fármacos , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica/fisiologia , Fosforilação , Proteínas de Plantas/farmacologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Neoplasias da Retina/metabolismo , Retinoblastoma/metabolismo , Transdução de Sinais , Células Tumorais Cultivadas
17.
J Neural Transm (Vienna) ; 129(8): 1031-1038, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35648256

RESUMO

Multiple sclerosis (MS) is a kind of central nervous system (CNS) autoimmune disease, which mainly damages nerves, the brain, and the spinal cord. Recently, several clinical cases reported the relativity between Coronavirus Disease 2019 (COVID-19) and the development of MS, but the mechanism of how COVID-19 affects the occurrence of MS was still not clear. It is bioinformatics technology that we use to explore the potential association at the gene level. The genetic information related to the two diseases was collected from the DisGNET platform for functional protein network analysis and used STRING to identify the complete gene set. The protein-protein interaction (PPI) network was analyzed by STRING. Finally, in the GEO database, we selected peripheral blood mononuclear cell (PBMC) RNA sequencing data (GSE164805, GSE21942) from COVID-19 patients and MS patients to verify the potential cross mechanism between the two diseases. The similar gene set of immune or inflammation existed between the patients with COVID-19 and ones with MS, including L2RA, IFNG, IL1B, NLRP3, and TNF. Interaction network analysis among proteins revealed that IL1B, P2RX7, IFNB1, IFNB1, TNF, and CASP1 enhanced the network connectivity between the combined gene set of COVID-19 and MS associated with NOD-like receptor (NLR) signaling. The involvement of NLR signaling in both diseases was further confirmed by comparing peripheral blood monocyte samples from COVID-19 and MS patients. Activation of NLR signaling was found in both COVID-19 and MS. The PBMC samples analyses also indicated the involvement of the NLR signaling pathway. Taken together, our data analyses revealed that the NLR signaling pathway might play a critical role in the COVID-19-related MS.


Assuntos
COVID-19 , Esclerose Múltipla , COVID-19/complicações , Biologia Computacional , Humanos , Leucócitos Mononucleares/metabolismo , Esclerose Múltipla/complicações , Esclerose Múltipla/genética , Proteínas NLR , Transdução de Sinais
18.
Immunol Invest ; 51(4): 931-946, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-33655821

RESUMO

To clarify the role of Y-27632, a selective inhibitor of Rho-associated coiled-coil forming protein kinase (ROCK), in acute lung injury (ALI) induced by myocardial ischemia/reperfusion (I/R). Mice were randomized into Sham, I/R, and Y-27632 (10, 20 or 30 mg/kg) + I/R groups, and hemodynamics, infarcted area, the protein concentration, neutrophils in bronchoalveolar lavage fluid (BALF), malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels were assessed. Pathological changes were evaluated by hematoxylin-eosin (HE) staining; protein and gene expression were measured by Western blotting, enzyme-linked immunosorbent assay (ELISA), immunohistochemistry and quantitative real-time reverse-transcription polymerase chain reaction (qRT-PCR); and apoptosis was assessed by terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling (TUNEL) staining. ROCK1 and ROCK2 expression was up-regulated in lung tissues of I/R mice compared to sham mice. Y-27632 decreased the protein concentration and the neutrophils in BALF in I/R mice, improved hemodynamics and reduced infarct size (IS)/area at risk (AAR) ratio. In addition, pathological changes in lung tissues of Y-27632-treated mice were mitigated, and these alterations were accompanied by decreases in MDA levels in lung tissues and increases in SOD and GSH-Px levels. Moreover, in I/R group, the number of apoptotic cells in lung tissue was higher than that in sham group, and p53, Caspase-3 and Bax expression was up-regulated; however, following treatment with Y-27632 (10, 20 and 30 mg/kg), these changes were reversed. Inhibition of ROCK pathway by Y-27632 ameliorated ALI in myocardial I/R mice by mitigating oxidative stress, inflammation and cell apoptosis.


Assuntos
Lesão Pulmonar Aguda , Traumatismo por Reperfusão Miocárdica , Lesão Pulmonar Aguda/tratamento farmacológico , Animais , Apoptose , Modelos Animais de Doenças , Glutationa Peroxidase , Camundongos , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Superóxido Dismutase
19.
Neoplasma ; 69(4): 794-806, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35400166

RESUMO

Secreted protein acidic and rich in cysteine (SPARC) plays a crucial role in the formation and progression of tumors. DNA methylation has become increasingly recognized as a frequent event of epigenetic alterations and one of the primary mechanisms of gene inactivation. The study aims to investigate the status of DNA methylation and the biofunction of SPARC in breast cancer. The qRT-PCR, BGS, and MSP methods were respectively employed to measure the relative mRNA expression levels and methylation status of SPARC. Additionally, the effects of SPARC on cell proliferation, migration, and invasion were examined in SPARC overexpression and knockdown cells. Immunohistochemical staining and western blot assay were used to examine the protein expression of genes. The expression levels of SPARC were found to be higher in breast cancer tissues and most breast cancer cells. The expression levels of SPARC in MDA-MB-231 and MCF-7 cells were significantly reversed by 5-Aza-dC treatment. Furthermore, the high expression and promoter DNA hypomethylation of SPARC were detected in triple-negative breast cancer tissues, while no expression changes of SPARC were found in luminal A breast cancer tissues. Overexpression of SPARC dramatically promoted MCF-7 cells migration and invasion, while knockdown of SPARC inhibited MDA-MB-231 cells migration and invasion. SPARC was involved in the epithelial-mesenchymal transition (EMT) process of breast cancer cells. The expression levels of mesenchymal markers N-cadherin, Vimentin, and ß-catenin were upregulated, while E-cadherin was downregulated in SPARC overexpressed breast cancer cells. Conversely, the expression levels of EMT-related genes demonstrated the opposite trend in SPARC knockdown cells. To conclude, high expression of SPARC regulated by promoter hypomethylation promotes breast cancer cells migration and invasion, thus SPARC may act as an oncogene and serve as a potential target for breast cancer therapy.


Assuntos
Neoplasias da Mama , Metilação de DNA , Osteonectina/genética , Neoplasias de Mama Triplo Negativas , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Transição Epitelial-Mesenquimal , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Prognóstico , Neoplasias de Mama Triplo Negativas/genética
20.
J Plant Res ; 135(1): 55-67, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34762207

RESUMO

Ephemeral plants are a crucial vegetation component in temperate deserts of Central Asia, and play an important role in biogeochemical cycle and biodiversity maintenance in desert ecosystems. However, the nitrogen (N) and phosphorus (P) status and interrelations of leaf-root-soil of ephemeral plants remain unclear. A total of 194 leaf-root-soil samples of eight ephemeral species at 37 sites in the Gurbantunggut Desert, China were collected, and then the corresponding N and P concentrations, and the N:P ratio were measured. Results showed that soil parameters presented no significant difference among the eight species. The total soil N:P was only 0.116 (geomean), indicating limited soil N, while the available soil N:P (4.896, geomean) was significantly larger than the total N:P. The leaf N (averagely 30.995 mg g-1) and P (averagely 1.523 mg g-1) concentrations were 2.64-8.46 and 0.93-3.99 times higher than the root N (averagely 8.014 mg g-1) and P (averagely 0.802 mg g-1) concentrations, respectively. Thus, leaf N:P (averagely 21.499) was 1.410-2.957 times higher than root N:P (averagely 11.803). Meanwhile, significant interspecific differences existed in plant stoichiometric traits. At the across-species level, N content scaled as the 3/4-power of P content in both leaves and roots. Leaf and root N:P ratios were mainly influenced by P; however, the leaf-to-root N or P ratio was dominated by roots. Leaf and root N, P contents and N:P were generally unrelated to soil nutrients, and the former presented lower variation than the latter, indicating a strong stoichiometric homeostasis for ephemerals. These results demonstrate that regardless of soil nutrient supply capacity in this region, the fast-growing ephemeral plants have formed a specific leaf-root-soil stoichiometric relation and nutrient use strategy adapting to the extreme desert environment.


Assuntos
Ecossistema , Solo , China , Nitrogênio/análise , Fósforo , Folhas de Planta/química , Plantas
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